U.S. patent application number 12/347264 was filed with the patent office on 2009-05-07 for recording method, recording and reproducing method, reproducing method, recording device, recording and reproducing device, and reproducing device for optical information recording and reproducing medium, and the optical information recording and reproducing medium.
Invention is credited to Toshiaki Iwanaga, Masashi Kubota, Masaki Nakano, Mitsuya Okada, Takaheru Shibatoko, Satoshi Sugaya, Hideki Tanabe.
Application Number | 20090116361 12/347264 |
Document ID | / |
Family ID | 31943926 |
Filed Date | 2009-05-07 |
United States Patent
Application |
20090116361 |
Kind Code |
A1 |
Okada; Mitsuya ; et
al. |
May 7, 2009 |
Recording Method, Recording and Reproducing Method, Reproducing
Method, Recording Device, Recording and Reproducing Device, and
Reproducing Device for Optical Information Recording and
Reproducing Medium, and the Optical Information Recording and
Reproducing Medium
Abstract
Optical information recording and reproducing medium 10 has two
recording layers of first and second recording layers 12 and 14,
from a laser beam incident surface side. In each control area 21,
recording layer management information containing at least
information indicating recording states of a plurality of areas
into which the inside of data recording area 22 of each recording
layer is divided is recorded. When recording or reproducing is
performed on the second recording layer 14, the recording layer
management information is checked, and a laser beam output is
changed based on a recording state of an area corresponding to the
first recording layer 12.
Inventors: |
Okada; Mitsuya; (Tokyo,
JP) ; Iwanaga; Toshiaki; (Tokyo, JP) ;
Shibatoko; Takaheru; (Tokyo, JP) ; Tanabe;
Hideki; (Tokyo, JP) ; Kubota; Masashi; (Tokyo,
JP) ; Nakano; Masaki; (Tokyo, JP) ; Sugaya;
Satoshi; (Tokyo, JP) |
Correspondence
Address: |
WHITHAM, CURTIS & CHRISTOFFERSON & COOK, P.C.
11491 SUNSET HILLS ROAD, SUITE 340
RESTON
VA
20190
US
|
Family ID: |
31943926 |
Appl. No.: |
12/347264 |
Filed: |
December 31, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10525079 |
Feb 18, 2005 |
7489620 |
|
|
PCT/JP03/10567 |
Aug 21, 2003 |
|
|
|
12347264 |
|
|
|
|
Current U.S.
Class: |
369/94 |
Current CPC
Class: |
G11B 7/24038 20130101;
G11B 7/00456 20130101; G11B 7/0062 20130101; G11B 7/00736 20130101;
G11B 2007/0013 20130101 |
Class at
Publication: |
369/94 |
International
Class: |
G11B 3/74 20060101
G11B003/74 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 21, 2002 |
JP |
2002-240122 |
Claims
1-7. (canceled)
8. An optical information recording and reproducing method for
recording/reproducing data on and from an optical information
recording/reproducing medium having a plurality of recording layers
which allow recording and reproducing by irradiation with a laser
beam, characterized in that when data reproducing is performed on
one recording layer, a recording state of the other recording layer
nearer a laser beam incident surface than said one recording layer
is examined by using recording layer management information and if
data recorded and unrecorded parts are mixed together in an area
whose recording state is examined, data is reproduced from said one
recording layer after dummy data is recorded in the data unrecorded
part.
9. An optical information recording method for recording data on an
optical information recording and reproducing medium having a
plurality of recording layers which allow recording and reproducing
by irradiation with a laser beam, characterized in that when data
recording is performed on one recording layer, a recording state of
the other recording layer nearer a laser beam incident surface than
said one recording layer is examined by using recording layer
management information and if data recorded and unrecorded parts
are mixed together in an area whose recording state is examined,
data is recorded on the one recording layer after dummy data is
recorded in said data unrecorded part.
10-16. (canceled)
17. An optical information recording and reproducing device for
recording or reproducing data on or from an optical information
recording and reproducing medium having a plurality of recording
layers which allow recording and reproducing by irradiation with a
laser beam, characterized by comprising at least reproducing means
for reproducing recording layer management information containing
at least information indicating recording states of the recording
layers, condensing means for condensing a laser beam on a recording
layer on/from which data is recorded or reproduced, and laser beam
power switching means for examining, when data is reproduced from
one recording layer by said condensing means, a recording state of
the other recording layer nearer a laser beam incident surface than
said one recording layer by using the recording layer management
information reproduced by said reproducing circuit, and changing
setting of a laser beam output for the recording or reproducing
based on a recording state of an area of said other recording layer
stacked on an upper part of an area in which the recording or
reproducing is performed, and in that if data recorded and
unrecorded parts are mixed together in the area of said other
recording layer stacked on the upper part of the area in which the
recording or reproducing is performed, said condensing means
reproduces data from said one recording layer after dummy data is
recorded in the data unrecorded part.
18. An optical information recording device for recording data on
an optical information recording and reproducing medium having a
plurality of recording layers which allow recording and reproducing
by irradiation with a laser beam, characterized by comprising at
least reproducing means for reproducing recording layer management
information containing at least information indicating recording
states of the recording layers, condensing means for condensing a
laser beam on a recording layer on which data is recorded, and
laser beam power switching means for examining, when data is
recorded on one recording layer by said condensing means, a
recording state of the other recording layer nearer a laser beam
incident surface than said one recording layer by using the
recording layer management information reproduced by said
reproducing means, and changing setting of a laser beam output for
the recording based on a recording state of an area of said other
recording layer stacked on an upper part of an area in which the
recording is performed, and in that if data recorded and unrecorded
parts are mixed together in the area of said other recording layer
stacked on the upper part of the area in which the recording is
performed, said condensing means records data on said one recording
layer after dummy data is recorded in the data unrecorded part.
19-22. (canceled)
Description
TECHNICAL FIELD
[0001] The present invention relates to a recording method, a
recording and reproducing method, a reproducing method, a recording
device, a recording and reproducing device, and a reproducing
device for an optical information recording and reproducing medium,
which perform data recording and reproducing by irradiation with a
laser beam, and the optical information recording and reproducing
medium.
BACKGROUND ART
[0002] An optical disk recording device (optical disk) using a
laser beam has a high recording density and can perform
large-capacity recording. Because of an operation in non-contact,
the device allows high-speed accessing and its practical
application as a large-capacity memory has progressed. The optical
disk is classified into a read only type which allows only
reproduction, a write-once type which allows only one recording
operation at a user side, and a rewritable type which allows
repeated recording operations at the user side. The read only type
is used for a compact disk or a laser disk, and various types are
used for an external memory of a computer and document and image
files.
[0003] In the read only type, a read signal is detected by using a
change in the amount of a reflected light from a concavo-convex pit
formed in the optical disk. In the write-once type, a read signal
is detected by using a change in the amount of a reflected light
from a very small pit formed in the optical disk, or a change in
the amount of a reflected light caused by a phase change of a phase
change recording film disposed in the optical disk.
[0004] In a magneto-optical disk which is one of the rewritable
types, recording is performed by irradiating a magneto-optical
recording film disposed in the optical disk with a high-output
laser beam to change a magnetized state. A read signal is detected
by using a magneto-optical effect of the magneto-optical recording
film and based on a change in a polarization surface of a reflected
light from the magneto-optical recording film. In a phase change
optical disk which is another embodiment of a rewritable type,
recording is performed by applying a high-output laser beam to
cause a phase change in a phage change recording film disposed in
the optical disk. As in the case of the phase change optical disk
of the recordable type, a read signal is detected based on a change
in the amount of a reflected light from the phase change recording
film.
[0005] Generally, in the optical disk, a thin recording film is
formed in a surface of a transparent resin material or glass
substrate in which a spiral track groove (pre-groove) is formed at
a pitch of 0.615 .mu.m to 1.6 .mu.m. When data is recorded or
reproduced, a recording signal of the data is recorded on the
recording film or a read signal is detected by tracking of a laser
beam spot along the track groove. Generally, only one layer of the
recording film is formed in the optical disk.
[0006] Incidentally, in the optical disk used for a file device or
the like, there is always a demand for achievement of a large
capacity, and attempts have been made to meet the demand. For
example, in a DVD-RAM, a "land and groove recording system" for
increasing a recording density by performing recording in both of
concave and convex parts of the track groove has been employed, and
put into practical use.
[0007] Additionally, there is a "multilayer" method as a method of
achieving a larger capacity. This is a method of multiplexing a
recording layer in a thickness direction of the optical disk. For
example, in a DVD-ROM, an optical disk in which a recording layer
is formed into two layers through a spacer layer of a thickness of
about 25 to 40 .mu.m has been put into practical use. According to
an operation principle of the multilayered optical disk, when
recording or reproducing is performed, a focus of a laser beam is
offset in a thickness direction to access a desired recording film.
In the DVD-ROM, by employing the two-layer formation, a recording
capacity is increased from 4.7 GB in the case of one layer of a
recording film to 8.5 GB, i.e., larger by about 1.8 times than that
in the case of one layer of the recording film.
[0008] Studies have been conducted on application of the
aforementioned multilayer method to the optical disks of the
write-once and rewritable types. For example, in the write-once
type, there are proposals of two-layer and even four-layer
formations (for example, H. Kitaura et al.; SPIE Proceedings, Vol.
4342, pp 340 to 347, Optical Data Storage 2001.). In the rewritable
type using the phase change recording layer, there is a proposal of
two-layer formation (for example, K. Nagata et al.; Jpn. J. Appl.
Phys., Vol. 38, (1998), pp 1679 to 1686). These proposals also
anticipate a capacity increase of about 1.8 from that in the case
of one layer of the recording film by the two-layer formation.
[0009] However, in the optical disk of the write-once type or the
rewritable type using the phase change recording film, the
following problem has occurred in the case of multilayer.
[0010] In the multilayered optical disk of the write-once type or
the rewritable type, a recording layer of a side near a laser beam
incident surface must have a fixed transmittance so that a laser
beam of predetermined intensity can normally reach a recording
layer of a farther side. However, in such an optical disk, because
of using of a change in reflectance of the recording film for
recording, the recording inevitably causes a change in
transmittance of the recording film. Thus, when recording is
performed on the recording film of the side near the laser beam
incident surface, a change occurs in intensity of a laser beam
which reaches the recording film of the farther side, causing a
problem of adversely affecting recording and reproducing on and
from these recording films. For example, irregular recording or
recording loss occurs during recording, or reproduction failures
occur during reproducing.
[0011] As one method of solving the problem, Japanese Patent No.
2928292 discloses a recording member, among optical information
recording members, in which management information for identifying
states of a plurality of recording layers is formed on a recording
layer nearest a light source, and a recording and reproducing
device. According to this method, however, when recording or
reproducing is performed on an information recording medium having
a plurality of recording layers, especially when recording or
reproducing is performed not on a recording layer of a side nearest
a laser beam incident surface but a recording layer of a farther
side, unless management information is formed in the layer, a
complex process of checking the management information by layer
jumping and moving to a desired recording layer by interlayer
jumping again is necessary for each recording or reproducing. Thus,
there is a drawback that the data recording or reproducing takes
long time.
[0012] Therefore, objects of the present invention are to provide
an optical information recording and reproducing medium, a
recording device, a recording and reproducing device, a reproducing
device, a recording method, a recording and reproducing method, and
a reproducing method, which can perform stable recording or
reproducing and a high-speed recording or reproducing operation on
the optical information recording and reproducing medium whose
recording film is multilayered.
DESCRIPTION OF THE INVENTION
[0013] That is, to achieve the object, according to the present
invention, an optical information recording and reproducing medium
having a plurality of recording layers which allow recording and
reproducing by irradiation with a laser beam is characterized in
that each recording layer comprises a recording area in which data
recorded by a user of a disk, that is, user data, is recorded, and
a recording management area in which recording layer management
information containing at least information indicating recording
states of a plurality of areas into which the inside of the
recording area is divided is recorded, and recording layer
management information of one recording layer is recorded in each
of the recording management areas of the one recording layer and
the other recording layer farther from a laser beam incident
surface than the one recording layer.
[0014] The recording layer management information of one recording
layer is recorded in each of the recording management areas of the
one recording layer and the other recording layer farther from the
laser beam incident surface than the one recording layer. Thus,
when recording or reproducing is performed on the other recording
layer, the recording layer management information of the one
recording layer can be quickly checked without shifting a focus of
a laser beam to the one recording layer by a layer jumping
operation. Additionally, when data is recorded and reproduced on
and from the other recording layer, a laser beam of relatively high
intensity passes through the one recording layer. Thus, a
possibility of losing the recording layer management information
due to data rewriting may be relatively high in the one recording
layer. Accordingly, by recording the recording layer management
information of the one recording layer on the other recording layer
in which the rewriting is difficult to occur, it is possible to
disperse risks of losing the recording layer management
information.
[0015] According to a preferred embodiment of the invention, defect
management information indicating a defect position of the
recording layer is further recorded in the recording management
area of each recording layer. By further recording the defect
management information of the recording layer management
information of each recording layer, when recording and reproducing
is performed on each recording layer, the defect management
information is checked, and an influence of a defect on the
recording or reproducing can be suppressed. Moreover, according to
the invention, preferably, the defect management information of the
one recording layer is recorded in a recording management area of
the other recording layer. Thus, similarly, it is possible to
quickly check the defect management information and to disperse
risks of losing the defect management information.
[0016] According to a preferred embodiment of the invention, a
guide groove of a wobbling shape is formed in at least one track of
the recording layer, and the guide groove of the wobbling shape is
subjected to track modulation for indicating a track address. By
forming the guide groove of the wobbling shape for indicating the
track address in the track of the recording layer, it is possible
to suppress a non-uniform light scattering in a surface in which
the guide groove is formed, and to perform stable recording or
reproducing on the recording layer farther from the laser beam
incident surface than the one recording layer.
[0017] According to an optical information recording and
reproducing method, a recording method and a reproducing method of
the present invention, the optical information recording and
reproducing method for recording and reproducing data on and from
an optical information recording and reproducing medium having a
plurality of recording layers which allow recording and reproducing
by irradiation with a laser beam is characterized in that when data
recording or reproducing is performed on one recording layer, a
recording state of the other recording layer nearer a laser beam
incident surface than the one recording layer is examined by using
recording layer management information, and setting of a laser beam
output is changed for the recording or reproducing based on whether
data has been recorded or not in an area stacked on an upper part
of an area in which the recording is performed.
[0018] When reproducing or recording of data is performed on the
one recording layer, the recording state of the other recording
layer nearer the laser beam incident surface than the one recording
layer is examined by using the recording layer management
information, and the laser beam output is adjusted for the
reproducing or reproducing based on whether data has been recorded
or not in an area stacked on an upper part of an area in which the
reproducing or reproducing is performed. Thus, by suppressing a
change in intensity of the laser beam applied to the one recording
layer, it is possible to perform stable data recording and
reproducing on one recording layer. The change is caused by a
difference of the recording state of the other recording layer.
[0019] According to the invention, under specific conditions, the
laser beam output for the recording or reproducing is increased if
data has been recorded in the area stacked on the upper part of the
area in which the recording or reproducing is performed.
Alternatively, under other conditions, the laser beam output for
the recording or reproducing is reduced if data has been recorded
in the corresponding area.
[0020] According to the preferred embodiment of the invention, an
area for recording data of the one recording layer is moved to
another area if data recorded and unrecorded parts are mixed
together in the area stacked on the upper part of the area in which
the recording is performed. When the mixed part is present in the
area stacked on the area in which the recording is performed, if
the recording is performed in this area, intensity of a laser beam
applied to the recording layer is not constant, running a risk of
generating irregular recording or recording loss. Thus, by moving
the area for recording the data of the one recording layer to
another area, it is possible to perform stable recording on the one
recording layer.
[0021] If the data recorded and unrecorded parts are mixed together
in the corresponding area of the other recording layer, data can be
reproduced from the one recording layer after dummy data is
recorded in the data unrecorded part. When the mixed recorded and
unrecorded parts are present in the corresponding area, if
reproducing is performed in this state, a fluctuation occurs in
intensity of the laser beam applied to the one recording layer
depending on the beam position, running a risk of generating
reproducing failures. Thus, by recording the dummy data in the
unrecorded part and making constant the intensity of the laser beam
applied to the one recording layer, it is possible to perform
stable data reproducing on the one recording layer.
[0022] When the mixed recorded and unrecorded parts exist in the
corresponding area, if recording is performed in this state,
intensity of the laser beam applied to the one recording layer is
not constant, running a risk of generating recording failures.
Thus, by recording the dummy data in the unrecorded part and making
constant the intensity of the laser beam applied to the one
recording layer, it is possible to perform stable data recording on
the one recording layer.
[0023] According to an optical information recording device, a
recording and reproducing device and a reproducing device of the
present invention, the optical information recording and
reproducing device for recording and reproducing data on and from
an optical information recording and reproducing medium having a
plurality of recording layers which allow recording and reproducing
by irradiation with a laser beam is characterized by comprising at
least reproducing means for reproducing from recording management
area a recording state as to whether data has been recorded or not
on a recording layer, condensing means for condensing a laser beam
on a recording layer on or from which data is recorded or
reproduced, and laser beam power switching means for examining,
when data recording or reproducing is performed on one recording
layer by the condensing means, a recording state of the other
recording layer nearer a laser beam incident surface than the one
recording layer by using recording layer management information
reproduced by the reproducing means, and changing setting of a
laser beam output for the recording or reproducing based on a
recording state of an area stacked on an upper part of an area in
which the recording or reproducing is performed. Thus, the device
can be constituted as a device which provides the aforementioned
effects.
[0024] According to the invention, preferably, the laser beam power
switching means increases or reduces the laser beam output for the
recording or reproducing in accordance with recording conditions if
data has been recorded in the area stacked on the upper part of the
area in which the recording or reproducing is performed. According
to the preferred embodiment of the invention, if data recorded and
unrecorded parts are mixed together in the area stacked on the
upper part of the area in which the recording or reproducing is
performed, the condensing means moves the area for recording to
another area. Alternatively, the condensing means can reproduce
data from the one recording layer after dummy data is recorded in
the unrecorded part.
[0025] Additionally, the condensing means can record data on the
one recording layer after the dummy data is recorded in the
unrecorded part.
[0026] According to the optical information recording and
reproducing medium of the invention, the recording layer management
information of the one recording layer is recorded in each of the
recording management areas of the one recording layer and the other
recording layer farther from the laser beam incident surface than
the one recording layer. Thus, it is possible to quickly check the
recording layer management information of the one recording layer
and to disperse risks of losing the recording layer management
information.
[0027] According to the optical information recording and
reproducing method, the recording method and the reproducing method
of the invention, when the data recording or reproducing is
performed on the one recording layer, the recording state as to
whether data has been recorded or not on the other recording layer
nearer the laser beam incident surface than the one recording layer
is examined, and the laser beam output for the recording or
reproducing is adjusted based on the recording state. Thus, it is
possible to perform stable data recording and reproducing on the
one recording layer. Moreover, according to the optical information
recording device, the recording and reproducing device and the
reproducing device, they can be constituted as devices which
provide the aforementioned effects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a sectional view showing a constitution of an
optical information recording and reproducing medium according to a
first embodiment of the present invention;
[0029] FIG. 2 is a sectional view showing a constitution of an
optical information recording and reproducing medium according to a
second embodiment of the present invention;
[0030] FIG. 3 is a sectional view showing a constitution of an
optical information recording and reproducing medium according to a
third embodiment of the present invention;
[0031] FIG. 4 is a sectional view showing a constitution of an
optical information recording and reproducing medium according to a
fourth embodiment of the present invention;
[0032] FIG. 5 is a plan view showing a guide groove in which a
pre-pit is formed;
[0033] FIG. 6 is a plan view showing a guide groove of a wobbling
shape;
[0034] FIG. 7 is a block diagram showing a constitution of an
optical information recording and reproducing device according to
an embodiment of the present invention;
[0035] FIG. 8 is a sectional view showing a constitution of an
optical information recording and reproducing medium according to
Embodiment 1;
[0036] FIG. 9 is a sectional view showing a constitution of an
optical information recording and reproducing medium according to
Embodiment 7; and
[0037] FIG. 10 is a graph showing a reproducing signal measured on
a conventional optical information recording and reproducing
medium.
BEST MODE FOR CARRYING-OUT OF THE INVENTION
[0038] FIG. 1 is a sectional view showing a layer structure of an
optical information recording and reproducing medium according to a
first embodiment of the present invention. A medium 10 is an
optical information recording and reproducing medium comprising a
plurality of recording layers as information recording surfaces
which allow recording and reproducing. Recording layer management
information of each recording layer is recorded not only on the
recording layer but also on all the recording layers farther from a
laser beam incident surface than the recording layer. Recording
layer management information of all the recording layers may be
recorded in each of recording management areas of all the recording
layers. In this case, data management of the recording management
areas is facilitated.
[0039] As multilayer-structured disks having plural recording
layers, there are a disk in which all are read only layers, all are
write-once recording layers, or all are rewritable recording
layers, and a disk in which a read only layer and a write-once
recording layer are combined together, a read only layer and a
rewritable recording layer are combined together, or a write-once
recording layer and a rewritable recording layer are combined, as a
combination of recording layers. The embodiment will be described
by way of case in which rewritable recording layers based on phase
changes are used for both recording layers.
[0040] That is, the medium 10 is an optical information recording
and reproducing medium of a two-layered phase change type. The
medium 10 comprises phase change type first and second recording
layers 12 and 14 on a substrate 11, and is constituted by optically
separating both recording layers from each other through a spacer
layer 13. The substrate 11 is made of a glass, metal or
polycarbonate resin, has a sufficient thickness of, for example,
about 0.6 mm to be provided with rigidity equal to that of an
optical disk such as a CD (Compact Disk) or a DVD (Digital
Versatile Disk), and a concentric circle guide groove or spiral
guide groove (not shown) is formed beforehand on its surface. The
first recording layer 12 comprises a lower protective film 12A, a
phase change recording film 12B and an upper protective layer 12C
which are sequentially stacked together, and is formed on the
substrate 11 by deposition method such as sputtering. The phase
change recording film 12B is made of a material which causes a
phage change by irradiation with a relatively high-output laser
beam.
[0041] The spacer layer 13 is formed to be sufficiently thick with
respect to a focal depth decided by a wavelength of a used laser or
performance of a condenser lens 24, and has a thickness of maximum
about 40 .mu.m. The space layer 13 is formed by using a method of
spreading a highly hardenable resin or a method of sticking a
film-like resin having a uniform thickness. The concentric circle
guide groove or spiral guide groove (not shown) is formed on the
surface of the spacer layer 13. The guide groove of the spacer
layer 13 is formed by using a method of transferring the hardenable
resin by a stamper or the like after it is spread or a method of
using a film in which a guide groove has been formed.
[0042] The second recording layer 14 comprises a lower protective
film 14A, a phase change recording film 14B, an upper protective
layer 14C, and a reflective film 14D which are sequentially stacked
together, and is formed on the spacer layer 13 by deposition method
such as sputtering. The phase change recording film 14B is made of
a material which causes a phage change by irradiation with a
relatively high-output laser beam as in the case of the phase
change recording film 12B. The reflective film 14D is made of a
material which exhibits a fixed reflectance with respect to an
incident light.
[0043] For example, the following materials can be cited for the
constituting layers. For each of the lower protective films 12A,
14A and the upper protective films 12C, 14C, a single film made of
dielectric material such as ZnS, SiO.sub.2, ZnS--SiO.sub.2, GeN,
GeCrN, AlN, TaO, GeAlN, SiO, Al.sub.2O.sub.3 or SiN, or a
multilayer film made of these dielectric materials can be used. For
each of the phase change recording films 12B, 14B, a thin film of
GeSbTe, GeSbSnTe, AgInSbTe, GeTe, SbTe, InSbTe or the like can be
used. For the reflective film 14D, Al, Ag, Au or NiCr, or an alloy
mainly consisting of these components can be used.
[0044] Each recording layer of the medium 10 has a control area 21
and a data recording area 22 in a radial direction of a disk
surface from a disk center 20 to a disk edge 23. In the data
recording area 22, data recorded by a user of the disk, i.e., user
disk, is recorded. In the control area 21, to perform good
recording or reproducing on or from the medium 10, control data for
controlling a recording device, a recording and reproducing device,
and a reproducing device is stored. There is no particular
limitation on the arrangement of the control area 21 and the data
recording area 22. The control area 21 may be arranged on an inner
peripheral side of the disk surface, and the data recording area 22
may be arranged on the outside thereof. Alternatively, as shown in
FIG. 1, the control areas 21 may be arranged by being dispersed
among a plurality of the data recording areas 22 spread from the
inner periphery to the outer periphery. Here, the control area 21
also functions as a recording management area. Needless to say, a
dedicated (exclusive) recording management area can be disposed
separately from the control area 21.
[0045] In the control area 21, recording layer management
information containing at least information indicating a recording
state of each of a plurality of areas into which the data recording
area 22 of the first recording layer 12 is divided is stored. The
recording layer management information of the data recording area
22 of the first recording layer 12 is stored not only in the
control area 21 of the first recording layer 12 but also in the
control area 21 of the second recording layer 14.
[0046] In the first recording layer 12, transmittances are usually
different between an area in which recording has been performed and
an area in which no recording has been performed. Physically, a
phase state change of the recording layer, a refractive index
change, a shape change, a phase change, a structural change or the
like occurs. In terms of a laser wavelength alone, however, it is a
phenomenon that the change is optically seen as a change in
transmittance. For example, in the case of the write-once type
recording film in which a transmittance of a recorded part having a
recording mark formed therein increases in comparison with that of
an unrecorded part, the amounts of lights reaching the second
recording layer 14 are different between a case in which the light
passes through the unrecorded part of the first recording layer 12
to reach the second layer 14 and a case in which the light passes
through the recorded part of the first recording layer 12 to reach
the second layer. This means that when recording is performed, even
if a laser beam of a similar output is emitted from a laser beam
source side, a difference is generated in the amounts of lights
reaching the second recording layer 14 depending on the recording
state of the first recording layer 12. When reproducing is
performed, depending on the recording state of the first recording
layer 12, even if a laser beam of a similar output is emitted from
the laser beam source side, a difference is generated in the
amounts of lights that reach the second recording layer 14 and are
reflected and received. In short, in the conventional medium,
phenomena such as irregular recording, recording loss and
reproducing failures easily occur, making it difficult to obtain
reliability of recording and reproducing.
[0047] FIG. 10 shows a change in a read signal when reproducing is
performed from the second recording film of the conventional
two-layered optical disk. Irregular recording 60 occurs because
when recording is performed on the second recording film, a laser
beam passes across the recorded and unrecorded parts of the first
recording film, a transmittance of the first recording layer is
reduced in the part of the irregular recording 60, and intensity of
the laser beam reaching the second recording layer is reduced.
[0048] On the other hand, according to the medium 10 of the
embodiment, the recording layer management information of the first
recording layer 12 is stored and when recording or reproducing is
performed on the second recording layer 14, it is not necessary to
move a focus of a laser beam to the first recording layer 12 by
layer jumping, making it possible to quickly check the recording
layer management information in the same recording layer. The
recording state of the first recording layer 12 is checked based on
the recording layer management information, and power reaching the
second recording layer 14 can be adjusted to be equal by adjusting
laser power based on the recording state of the first recording
layer 12. Further, according to the medium 10, when recording or
reproducing is performed on the second recording layer 14, a laser
beam of relatively high intensity passes through the first
recording layer 12. Accordingly, in this case, a possibility of
losing the recording layer management information because of data
rewriting may be relatively high in the first recording layer 12.
Thus, for the recording layer management information of the first
recording layer 12, the same data is recorded in the control area
21 of the second recording layer 14 in which the aforementioned
rewriting is difficult to occur, making it possible to disperse
risks of losing the recording layer management information.
[0049] According to the medium 10 of the embodiment, defect
management information indicating a defect position of the data
recording area 22 of each recording layer is stored in the control
area 21. The defect management information of the first recording
layer 12 is stored not only in the control area 21 of the first
recording layer 12 but also in the control area 21 of the second
recording layer 14.
[0050] Defects (defective parts) of the optical information
recording and reproducing medium generally occurs because of
certain non-uniformities, for example, presence of stuck things, a
shape abnormality of the guide groove, exfoliation of the recording
film, incursion of impurities into the substrate, and the like.
These defects cause laser beam scattering, affecting a
transmittance of the laser beam. That is, if there is a defect in
the first recording layer 12, recording and reproducing on the
second recording layer 14 will be affected. Accordingly, by
managing the defect management information of the first recording
layer 12, and by using a predetermined method described later, it
is possible to suppress the influence of the defect in the first
recording layer 12 on the recording and reproducing on the second
recording layer 14. Moreover, by storing the defect management
information of the first recording layer 12 in the control area 21
of the second recording layer 14, as in the case of the recording
layer management information, it is possible to quickly check the
information and to disperse risks of losing the defect management
information.
[0051] Now, the recording layer management information will be
described in detail. The recording layer management information
must contain at least information indicating recording state of
each of areas into which the inside of the data recording area is
divided. However, a form of the management information is free. For
example, as information indicating a recording state, a combination
of (recording layer number, start address of recorded part, and end
address of recorded part) or a combination of (recording layer
number, target area number, start address of recorded part, and end
address of recorded part) may be employed. If defect management
information is contained, a combination of (kind of information:
recorded information or defect information, target area number,
start address of recorded part, end address of recorded part, start
address of recording inhibited part due to defect, and end address
of recording inhibited part due to defect) or a combination of
(flag indicating defect information, target area number, start
address of recording inhibited part due to defect, and end address
of recording inhibited part due to defect) may be employed. Their
information may be mixed to form management information.
[0052] When management is performed based on a radial position of
an optical head used for recording and reproducing, a combination
of (recording layer number, start radius of recorded part, and end
radius of recorded part) or a combination of (recording layer
number, target area radius, start radius of recorded part, and end
radius of recorded part) may be employed. If defect management
information is contained, a combination of (kind of information:
recorded information or defect information, target area radius,
start radius of recorded part, end radius of recorded part, start
radius of recording inhibited part due to defect, and end radius of
recording inhibited part due to defect) or a combination of (flag
indicating defect information, target area radius, start radius of
recording inhibited part due to defect, and end radius of recording
inhibited part due to defect). Additionally, their information may
be combined to form management information, and can be used
together with the aforementioned addresses.
[0053] When user data continuous for a long time such as video or
audio data is managed, a position of a recording start time zero
may be set as a reference on the medium, and information may be
managed based on a recording time with it as a reference. In this
case, a combination of (recording layer number, recording start
time of recorded part, and end time of recorded part) or a
combination of (recording layer number, target area start time,
start time of recorded part, and end time of recorded part) may be
employed. If defect management information is contained, a
combination of (kind of information: recorded information or defect
information, recording start time of target area, start time of
recorded part, end time of recorded part, start time of recording
inhibited part due to defect, and end time of recording inhibited
part due to defect) or a combination of (flag indicating defect
information, recording start time of target area, start time of
recording inhibited part due to defect, and end time of recording
inhibited part due to defect) may be employed. Additionally, their
information may be combined to form management information, and can
be used together with the aforementioned addresses and the radial
positions.
[0054] As information indicating a recording state, a form of a bit
map may be employed. For example, to enable identification of an
ECC block usage for each recording layer, a bit map can be created
in which "1" shows a recorded block and "0" for unrecorded one. In
this case, a head bit corresponds to a head ECC block of the
recording layer. This bit map may be formed by a sector unit, or
separated by an area.
[0055] Further, information indicating a defect may be in a form of
a bit map. For example, a bit map is created in which presence of a
defect is "1" and no defect is "0" in the ECC block unit for each
recording layer. In this case, a head bit corresponds to a head ECC
block of the recording layer. Needless to say, this bit map may be
formed by a sector unit, or separated by an area.
[0056] The case in which the recording management information
indicates presence or no presence of recording, or presence or no
presence of a defect has been described. In addition to this
information, information indicating a kind of contents, information
indicating the number of repeated recording times of the recorded
part, and the like may be included.
[0057] According to the medium 10, for the guide groove in which
the first recording layer 12 is formed, a guide groove (wobbling
groove) 31 formatted into a wobbling shape meandering in a
direction orthogonal to a tracking direction similar to that shown
in FIG. 6 is employed. In the optical disk or the like, generally,
an address imparting part 32 is disposed in a part of the guide
groove in a trangential direction to impart address information of
each track constituting the guide groove.
[0058] As an address imparting method frequently used
conventionally, there is a method of forming a pre-bit 33 similar
to that shown in FIG. 5. According to this method, a normal shape
guide groove 34 having no meandering is employed. In the address
imparting part 32, an irregular island-shaped pre-bit 33 is formed
for each track in place of the guide groove 34. By this method,
however, groove shapes are greatly different between the address
imparting part 32 and other areas, making surface scattering of
both areas greatly different. Thus, intensity of a transmitted
light near the address imparting part 32 is disturbed, causing a
difficulty of stable recording and reproducing on the second
recording layer 14.
[0059] Thus, it is advisable to employ the wobbling groove 31 of
the shape having repeated constant meandering shown in FIG. 6 for
the guide groove of the medium 10 of the embodiment. In the address
imparting part 32, the wobbling groove 31 is directly formed, and
its shape is partially irregular. In the embodiment shown in FIG.
6, a phase of repeated meandering is shifted by 180.degree. at a
position 35. As a method of making the groove shape irregular, in
addition to the above, for example, there is a method of shifting a
cycle of repeated meandering within .+-.10% in the address
imparting part 32. In any case, in the case of forming the wobbling
groove 31, a difference in groove shape between the address
imparting part 32 and the other groove forming part is small in
comparison with that in the case of forming the pre-bit 33, and a
difference in surface scattering between both areas is small. Thus,
it is possible to suppress disturbance of the intensity of the
transmitted light even near the address imparting part 32 and to
perform stable recording and reproducing on the second recording
layer 14.
[0060] According to the medium 10 of the embodiment, by storing the
recording layer management information and defect management
information of the first recording layer 12, it is always possible
to perform stable recording and reproducing by checking the
information when the recording or reproducing is performed on the
second recording layer 14. By storing the recording layer
management information and defect management information of the
first recording layer 12 in the control area 21 of the second
recording layer 14, it is possible to quickly check the information
and to disperse risks of losing the information. Moreover, by
forming the wobbling groove 31 in the first recording layer 12, it
is possible to suppress the disturbance of the intensity of the
transmitted light near the address imparting part 32, thereby
enabling stable data recording and reproducing.
[0061] A recording and reproducing method, a recording method and a
reproducing method for the medium 10 of the embodiment will be
described. First, when recording or reproducing is performed on the
second recording layer 14, the control area 21 of the second
recording layer 14 is checked. In this case, for a target area 26
of the second recording layer 14 in which the recording or
reproducing is performed, checking is made as to whether a
recording state of an area 27 of the first recording layer 12
stacked on an upper part of the second recording layer is recorded
or unrecorded. The area 27 is set on the basis of the spread of a
laser beam 25 on the first recording layer 12 when the laser beam
25 is focused on the second recording layer 14, and by considering
a track width of the second recording layer 12 and a disk
decentration (decentering) shifting amount between the first and
second recording layers 12 and 14. Next, based on the checked
recording state of the area 27 of the first recording layer 12, a
laser beam output is properly changed to a predetermined output,
and the recording or reproducing is performed on the second
recording layer 14. For example, when recording on the first
recording layer causes a change of an average transmittance of the
recording area from 50% to 61%, the amount of a laser beam 25
transmitted to the second recording layer is accordingly changed.
In this case, if a laser beam output to the first recording layer
recorded part is set to be 0.82 times that of the unrecorded part,
equal power reaches the second recording layer. In the case of
reproducing, no fluctuation in a detection amount of a
photo-detector for generating a reproducing signal than in the
amount of light reaching the second recording layer is preferable.
Accordingly, in the case of exemplified conditions, if a
reproducing laser beam output to the first recording layer recorded
part is set to be 0.67 times that of the unrecorded part, equal
power reaches the photo-detector. Thus, when the recording or
reproducing is performed on the second recording layer 14, optimal
transmitted light intensity is obtained, making it possible to
perform stable recording and reproducing.
[0062] It is to be noted that with regard to power conditions
during the recording or reproducing, for the cases of recording and
non-recording on the first recording layer, prescribed values may
be prerecorded in a desired area of the medium, read and set.
Alternatively, the recording and reproducing device may identify
the medium, read prescribed values specified for the medium and set
the values.
[0063] If the checked recording state of the area 27 of the first
recording layer 12 indicates a mixture of recorded and unrecorded
parts, the following is carried out. When recording is performed,
it is difficult to perform stable recording on the second recording
layer 14. Accordingly, basically, it is preferable to avoid
recording on the second recording layer 14 of this area, and
recording is carried out by moving to an unrecorded alternative
(substitute) area. Thus, it is possible to prevent irregular
recording or recording loss.
[0064] On the other hand, when reproducing is performed, first,
pseudo recording is carried out on the unrecorded part of the area
of the mixed state, thereby eliminating the mixed state. Next, a
laser beam output is changed to a predetermined output of the
recording time, and reproducing is performed. Accordingly, stable
reproducing is carried out by irradiating the second recording
layer 14 with a transmitted light of uniform intensity, making it
possible to suppress reproducing failures. It is advisable to use
prescribed pseudo data for the pseudo recording.
[0065] When recording or reproducing is performed on the second
recording layer 14, it is advisable to check the defect management
information of the first recording layer 12. The defect management
information is checked and when there is a defect in the area 27 of
the first recording layer 12 stacked on the upper part of the area
of the second recording layer 14 in which the recording is
performed, for example, means for carrying out recording by moving
to an alternative area can be employed. Thus, it is possible to
suppress irregular recording or recording loss.
[0066] According to the recording and reproducing method, the
recording method and the reproducing method of the medium 10 of the
embodiment, when recording or reproducing is performed on the
second recording layer 14, a recording state of the area 27 of the
first recording layer 12 is checked based on recording layer
management information, and a laser beam output is changed so that
intensity of a transmitted light can be optimal. If the area 27 is
in a mixed state, recording is carried out by moving to an
alternative (substitute) area, or reproducing is carried out after
pseudo recording is performed. Further, a defect position of the
first recording layer 12 is checked based on defect management
information, and predetermined means is implemented. By these
methods, it is possible to suppress conventional problems such as
irregular recording, recording loss and recording failures.
[0067] FIG. 2 is a sectional view showing a layer structure of an
optical information recording and reproducing medium according to a
second embodiment of the present invention. The case of using the
substrate 11 having rigidity and the guide groove formed therein
has been described. As the layer structure of the optical
information recording and reproducing medium, however, a medium 40
shown in the drawing may be employed. The medium 40 is an optical
information recording and reproducing medium which employs a
condenser lens 30 or the like having a high numerical aperture (NA)
to shorten a focal length, thereby achieving a high density.
Accordingly, the medium has a constitution in which a thick cover
layer 15 is formed on a laser beam incident surface and a substrate
11 having a large thickness is formed on a side opposed to the
laser beam incident surface.
[0068] That is, the medium 40 is similar in constitution to the
medium 10 of the first embodiment except for the fact that the
thick cover layer 15 having a film thickness of about 0.1 mm is
disposed on the laser beam incident surface side in place of the
substrate 11, and the substrate 11 is disposed on the backside of
the second recording layer 14. With this constitution, the medium
40 can achieve a high density equal to or higher than that of, for
example, a DVD.
[0069] FIG. 3 is a sectional view showing a layer structure of an
optical information recording and reproducing medium according to a
third embodiment of the present invention. For the layer structure
of the optical information recording and reproducing medium, a
structure similar to that of a medium 41 shown in the drawing may
be employed. In the medium 41, the constitution of the medium 10
shown in FIG. 1 is change to double-surface constitution. The
medium 41 has a constitution in which the second recording layers
14 of the two media 10 are set to face each other and stuck
together through an adhesive layer 16. With this constitution, it
is possible to achieve a much larger capacity. It is to be noted
that one of the stuck media 10 may be a dummy substrate when
necessary.
[0070] FIG. 4 is a sectional view showing a layer structure of an
optical information recording and reproducing medium according to a
fourth embodiment of the present invention. For the layer structure
of the optical information recording and reproducing medium, a
structure similar to that of a medium 42 shown in the drawing may
be employed. In the medium 42, the constitution of the medium 40
shown in FIG. 2 is change to double-surface constitution. The
medium 42 has a constitution in which the substrate 11 is made
common and the two media 40 are formed on both surfaces of the
substrate 11. With this constitution, it is possible to achieve a
much larger capacity.
[0071] The optical information recording and reproducing medium
using the phase change recording layer for the recording layer has
been described. However, the media of the first to fourth
embodiments can be applied to, for example, a so-called recordable
medium (R medium) of a write-once type. In this case, for a
recording layer, a thin film containing an organic dye with fixed
absorption to a used laser wavelength, a low melting point metal
such as Sn, Bi, In, Te or Pb, or an easily deformable material such
as Si or Ge is employed. A constitution may also be employed in
which a dielectric protective film or a reflective film is formed
on and below the organic pigment or the thin film.
[0072] FIG. 7 is a block diagram showing a constitution of an
optical information recording and reproducing device according to
an embodiment of the present invention. A basic constitution is
that the device comprises an optical information recording and
reproducing medium having a plurality of recording layers which
allow recording and reproducing by irradiation with a laser beam,
an optical head for condensing a laser beam on a recording layer on
which data recording or reproducing is performed, a recording and
reproducing circuit, recording layer management
information.cndot.reproducing means used for reproducing recording
layer management information containing at least information
indicating a recording state of the recording layers, recording
power setting means and reproducing power setting means which
function as laser beam power switching means for changing setting
of recording laser beam output, and a pseudo data generation
circuit. A device 50 performs recording and reproducing on the
optical information recording and reproducing medium while
transferring data with an outside host.
[0073] The device 50 comprises an optical disk 51 which is an
optical information recording and reproducing medium, an optical
head 52 for performing an optical operation on the optical disk 51,
a spindle motor 53 for supporting and rotating the optical disk 51,
a circuit group 54 for controlling the optical head 52 and the
spindle motor 53, a controller 110 for performing the entire
control for the circuit group 54, and an interface 111 for
transferring data with the outside host.
[0074] The circuit group 54 comprises a rotation control circuit
101, a servo control circuit 102, a recording and reproducing
circuit 103, a recording data processing circuit 104, a pseudo data
generation circuit 105, a recording power setting circuit 106, a
reproducing power setting circuit 107, a reproduced data processing
circuit 108, and a recording layer management
information.cndot.reproducing circuit 109.
[0075] The optical disk 51 is the optical information recording and
reproducing medium having two recording layers as in the case of
each of the first to fourth embodiments. The optical head 52
comprises a laser beam source for irradiating the optical disk 51
with a laser beam, and a photo-detector for detecting a reflected
light from the optical disk 51 during reproducing. The optical head
52 causes the laser beam source to emit a laser beam by using a
driving signal from the recording and reproducing circuit 103, and
condenses the laser beam in a predetermined position on the
rotating optical disk 51. During reproducing, the reflected light
from the optical disk 51 is detected by the photo-detector. The
laser beam source emits a laser beam of an output higher during
recording than that during reproducing. The spindle motor 53 is
controlled by the rotation control circuit 101 to rotate the
optical disk 51 to a predetermined rotating position.
[0076] The rotation control circuit 101 controls rotation of the
spindle motor 53. The servo control circuit 102 performs focus
control, tracking control and position control of the optical head
52 based on a servo error signal from the recording and reproducing
circuit 103 and a command from the controller 110.
[0077] During reproducing, the recording and reproducing circuit
103 amplifies a signal detected by the photo-detector of the
optical head 52 and generates a reproduced data signal, a signal
about recording layer management information stored in the control
area 21, a focus servo error signal, a tracking servo error signal
and the like. During recording, a signal received from the
recording data processing circuit 104 is supplied to the optical
head 52.
[0078] The recording data processing circuit 104 adds an error
correction code to recording data received from the interface 111,
and transmits the data to the recording and reproducing circuit
103. In the case of performing pseudo recording, pseudo data
received from the pseudo data generation circuit 105 is processed
to be data for recording, and transmitted to the recording and
reproducing circuit 103.
[0079] During the pseudo recording, the pseudo data generation
circuit 105 generates pseudo data, and transmits the data to the
recording data processing circuit 104. The recording power setting
circuit 106 changes a laser beam output to a predetermined value on
the basis of a command from the controller 110 when necessary for
the recording. The reproducing power setting circuit 107 changes
the laser beam output to a predetermined value on the basis of a
command from the controller 110 when necessary for the
reproducing.
[0080] The reproduced data processing circuit 108 demodulates a
reproduced data signal received from the recording and reproducing
circuit 103 to be reproduced data, subjects the data to error
correction, and then transmits the data to the interface 111. The
recording layer management information.cndot.reproducing circuit
109 receives a signal from the reproduced data processing circuit
108 during reproducing in the control area 21, generates data about
a recording state of the control area 21, and transmits the data to
the controller 110.
[0081] The controller 110 controls their circuits, the interface
and the like. The interface 111 receives recording and reproducing
command data and recording data from the outside host, and
transmits reproduced data thereto.
[0082] With this constitution, the device 50 can be constituted as
the optical information recording and reproducing device having
effects similar to those of the optical information recording and
reproducing media of the first to fourth embodiments.
[0083] Next, description will be made for a recording and
reproducing method, a recording method, and a reproducing method
according to an embodiment of the present invention which use the
aforementioned optical information recording and reproducing medium
and the device. The description will be made on the assumption that
recording and reproducing is performed on a phase change type
recording film. The optical disk 51 that is an optical information
recording and reproducing medium has a constitution of two
recording layers, and recording or reproducing is performed by
using the optical head 52. As shown in FIG. 1, the control areas 21
are disposed in the first and second recording layers 12 and 14 of
the optical disk 51, and recording layer management information
regarding a recording state of the first recording layer 12 is
stored therein. In other words, as described above, the control
area 21 functions as a recording management area.
[0084] There is no limitation on arrangement of the recording layer
management information in the control area for storing the
recording layer management information. For example, seen from the
laser beam incident side, the recording layer management
information of the second recording layer may be arranged by being
superposed on a deep side of the recording layer management
information arranged position of the first recording layer.
Alternatively, the recording layer management information of the
second recording layer may be arranged in a position not superposed
on the deep side of the recording layer management information
arranged position of the first recording layer.
[0085] In the case of arranging the recording layer management
information of the second recording layer in the position not
superposed on the deep side of the recording layer management
information arranged position of the first recording layer, the
recording or reproducing on the second recording layer is not
affected by the recorded state of the first recording layer, and
thus reliability of recording or reproducing of the recording layer
management information is higher.
[0086] At least the recording layer management information of the
first recording layer only needs to be recorded on the first
recording layer. However, at least the recording layer management
information of the first recording layer must be recorded on the
second recording layer, and recording of the recording layer
management information of the second recording layer is preferable
for a recording and reproducing operation of the second recording
layer.
[0087] The recording layer management information of each layer is
updated each time recording is performed on each layer.
Accordingly, in the case of a write-once type, update information
is added in the recording management area. Therefore, this area is
required to secure sufficiently. In the case of a rewritable type,
update information may be added, or old data may be rewritten.
[0088] Next, a procedure of updating the recording layer management
information will be described. When recording is performed on the
first recording layer, for example, a set of start and end
addresses among addresses used for the recording and a used area
number is recorded as recording layer management information in the
recording management areas of the first and second recording
layers. When recording is performed on the second recording layer,
for example, a set of start and end addresses among used addresses
and a used area number is recorded as recording layer management
information in the recording management area of the second
recording layer. A similar operation is performed when recording
layer management information containing position information or
time information is used.
[0089] In the case of recording layer management information in a
bit map form, when recording is performed on the first recording
layer, for example, a desired bit of a bit map equivalent to an ECC
block used for recording is changed and updated to "1", and
recorded as recording layer management information in the recording
management areas of the first and second recording layers. When
recording is performed on the second recording layer, for example,
similarly, a desired bit of a bit map equivalent to an ECC block
used for recording is changed and updated to "1", and recorded as
recording layer management information in the recording management
area of the second recording layer.
[0090] Next, a procedure of updating defect management information
will be described. When recording or reproducing is performed on
the first recording layer and a defect unusable for recording or
reproducing is found, for example, a set of defect start and end
addresses among addresses containing the defect and an area number
in which a defect is present is recorded as defect management
information in the recording management areas of the first and
second recording layers. When recording or reproducing is performed
on the second recording layer and a defect unusable for recording
or reproducing is found, for example, a set of defect start and end
addresses among addresses containing the defect and an area number
in which a defect exists is recorded as defect management
information in the recording management area of the second
recording layer. A similar operation is performed when defect
management information containing position information or time
information is used.
[0091] In the case of recording defect management information in a
bit map form, when recording or reproducing is performed on the
first recording layer and a defect unusable for recording or
reproducing is found, for example, a desired bit of a bit map
equivalent to an ECC block in which a defect exists is changed and
updated to "1", and recorded as defect management information in
the recording management areas of the first and second recording
layers. When recording or reproducing is performed on the second
recording layer and a defect unusable for recording or reproducing
is found, for example, similarly, a desired bit of a bit map
equivalent to an ECC block in which a defect exists is changed and
updated to "1", and recorded as defect management information in
the recording management area of the second recording layer.
[0092] As described above, an address is allocated to each track of
the optical disk 51 by a predetermined address imparting method.
Thus, after an address can be checked, a radius of each track on
the optical disk can be established. In a medium constituted by
stacking a plurality of recording layers, the stacking of the
recording layers is carried out highly accurately, and thus disk
decentration (decentering) shifting of each recording layer is very
small. Accordingly, a track radius of a certain address of the
second recording layer 14 is substantially equal to that of a
corresponding address of the first recording layer 12. Thus, when a
predetermined track of the second recording layer 14 is specified,
the device 50 can check a recording state of a track by specifying
the track in a corresponding position of the first recording layer
12 through an address and checking recording layer management
information.
[0093] During recording or reproducing, first, based on a command
from the controller 110, an address of a track of the second
recording layer 14 for performing recording is established. Next,
the control area 21 of the second recording layer 14 is checked,
and whether a recording state of a track included in the area 27 of
the first recording layer 12 stacked on an upper part of an area of
the second recording layer 14 in which recording is performed is
recorded or unrecorded, is checked. Next, based on the checking, a
laser beam output is properly changed to a predetermined output,
and recording or reproducing is performed on the second recording
layer 14. Accordingly, during the recording or reproducing on the
second recording layer 14, optimal transmitted light intensity is
obtained, making it possible to perform stable recording or
reproducing. Correction conditions in this case can be decided
beforehand in accordance with the constitution of the optical disk
51. Thus, the conditions may be prerecorded in the control area 21
of the second recording layer 14, or pre-stored in the device
50.
[0094] If the checked recording state of the area 27 indicates a
mixture of recorded and unrecorded parts, the following is carried
out. When recording is performed, the recording is carried out by
moving to an alternative (substitute) area which is an unrecorded
part. Thus, it is possible to prevent irregular recording. On the
other hand, when reproducing is performed, first, pseudo recording
is carried out in the unrecorded part of the area of the mixture to
eliminate the mixed state. Next, reproducing is carried out by
changing a laser beam to a predetermined output. Thus, the second
recording layer 14 is irradiated with a transmitted light of
uniform intensity to perform stable reproducing, making it possible
to suppress a reproducing failure which has conventionally been a
problem. For the pseudo recording, it is advisable to a specific
pattern signal prerecorded in the pseudo data generation circuit
105.
[0095] Furthermore, as another recording method, first, pseudo
recording is performed in the unrecorded part of the mixed area to
eliminate the mixed state. Next, recording is carried out by
changing a laser beam to a predetermined output. Thus, the second
recording layer 14 is irradiated with a transmitted light of
uniform intensity to perform stable recording, making it possible
to suppress irregular recording and recording loss which have
conventionally been problems. For the pseudo recording, as in the
case of the aforementioned reproducing method, it is advisable to
use a specific pattern signal prerecorded in the pseudo data
generation circuit 105.
EMBODIMENTS
[0096] To check effectiveness of the present invention, media of
the following Embodiments 1 to 16 were manufactured and tested. The
Embodiments 1 to 16 are concrete embodiments of the optical
information recording/reproducing media of the first to fourth
embodiments, and the optical information recording/reproducing
devices of the embodiments, and modified embodiments accompanied by
various changes. The Embodiments 1 to 6, the Embodiments 7 to 11,
and the Embodiments 12 to 16 use the same recording and reproducing
media and the same recording and reproducing devices.
Embodiment 1
[0097] FIG. 8 is a sectional view showing a constitution of an
optical information recording/reproducing medium of the embodiment.
A medium 44 has a constitution in which two substrates having
recording layers formed on surfaces are set to face each other and
stuck together through an ultraviolet curing resin having a
predetermined thickness.
[0098] That is, as a first substrate 17, a polycarbonate resin
substrate having an outer diameter of 120 mm, an inner diameter of
15 mm, and a substrate thickness of 0.6 mm was used. For the first
substrate 17, a substrate in which a wobbling groove 31 shown in
FIG. 6 was formed beforehand by mastering was used. A shape of the
wobbling groove 31 had a depth of 60 nm and a track pitch of 0.74
.mu.m. The wobbling groove 31 was spiral and formed so as to
achieve a wobbling frequency of 700 kHz when it was rotated from
the inner periphery to the outer periphery of the first substrate
17 at a linear velocity of 3.9 m/sec. A radius 22 mm to 24 mm of
the first substrate 17 was set as a control area 21, and a radius
24 mm to 58 mm of its outside was set as a data recording area 22.
Pre-designated addresses were allocated to tracks of the control
area 21 and the data recording area 22 in accordance with the
aforementioned method.
[0099] As a first recording layer 12, a lower protective film 12A
made of ZnS--SiO.sub.2, a phase change recording film 12B made of
GeSbTe, and an upper protective film 12C made of ZnS--SiO.sub.2
were sequentially formed on the first substrate 17 by sputtering
method.
[0100] As a second substrate 18, a polycarbonate resin substrate
having an outer diameter of 120 mm, an inner diameter of 15 mm, and
a substrate thickness of 0.6 mm was used. A wobbling groove 31 was
formed on a surface of the second substrate 18 by mastering, and
formed into a spiral shape reverse to that of the wobble groove 31
formed in the surface of the first substrate 17. A depth, a track
pitch, and a wobbling frequency of the wobbling groove 31 of the
second substrate 18, and constitution of a control area 21 and data
recording area 22, and the like were similar to those of the first
substrate 17.
[0101] As a second recording layer 14, a reflective film 14D made
of Al--Ti, an upper protective film 14C made of ZnS--SiO.sub.2, a
phase change recording film 14B made of GeSbTe, and a lower
protective film 14A made of ZnS--SiO.sub.2 were sequentially formed
on the second substrate 18 by sputtering method.
[0102] Next, as a spacer layer 13, an ultraviolet curing resin was
developed with a thickness of 40 .mu.m on the first recording layer
12 by spin-coating method. Subsequently, the first and second
recording layers 12 and 14 were set to face each other, the first
and second substrates 17 and 18 were stuck together by suppressing
decentrations thereof, and the ultraviolet curing resin was cured
by ultraviolet rays.
[0103] Subsequently, all of data recording areas of the first and
second recording layers 12 and 14 in which recording would be
performed were initialized by using an initialization device. That
is, by setting a crystal state which was an initial state
equivalent to non-recording, the medium 44 was formed. As in the
case of the medium 10 of the first embodiment, recording layer
management information and defect management information of the
first recording layer 12 were stored in the first and second
recording layers 12 and 14.
[0104] Optical characteristics of the medium 44 of the embodiment
were measured. When a laser beam having a wavelength of 650 nm was
applied from the first substrate 17 side, in the case of the first
recording layer 12 alone, in a crystal state of an unrecorded time,
a reflectance was 10% and a transmittance was 50% and in an
amorphous state of an recorded time, a reflectance was 2.5% and a
transmittance was 72%. In the case of the second recording layer 14
alone, a reflectance was 12% in a crystal state of an unrecorded
time, and a reflectance was 30% in an amorphous state of a recorded
time.
[0105] Under similar conditions, for the medium 44, a reflectance
from the second recording layer 14 was 3% when the second and first
recording layers 14 and 12 were unrecorded. However, after the
first recording layer 12 was recorded, the reflectance from the
second recording layer 14 was about 4.5%. Additionally, a
reflectance from the second recording layer 14 was 7.5% after the
second recording layer 14 was recorded while the first recording
layer 12 was unrecorded. However, after the first recording layer
12 was recorded, the reflectance from the second recording layer 14
was about 11%.
[0106] Recording was tried on the medium 44 by using an optical
head for a phase change recording medium. A laser beam wavelength
of the optical head was 650 nm, and NA of a condenser lens was
0.65. For the recording, the device 50 of the embodiment described
above with reference to FIG. 7 was used.
[0107] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the first recording layer 12. In
this case, in accordance with the aforementioned procedure,
information indicating that addresses (address 69680 hex to address
7E2DF hex) allocated to the radius 30 mm to 32 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 of the second recording layer 14.
[0108] Subsequently, a host transmitted a command for performing
recording in the radius 30.5 mm to 31.2 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 to
32 mm of the first recording layer 12, and transmitted the status
data to the controller 110. Next, by a command from the controller
110, a focus of a laser beam of the optical head 52 was moved to a
position of the radius 30.5 mm of the second recording layer 14.
Subsequently, the controller 110 transmitted a command for reducing
a laser beam output (recording power) from an initial value 12 mW
to 10 mW to the recording power setting circuit 106. By such a
series of operations or the like, good recording was carried out
for the radius 30.5 mm to 31.2 mm which was a desired area.
[0109] As described above, it was possible to check that when the
first recording layer 12 was in the recorded state, good recording
was carried out on the second recording layer 14 by reducing the
laser beam output.
Embodiment 2
[0110] Reproducing was tried from the second recording layer 14 by
using the medium 44 of the Embodiment 1, and the device 50 of the
embodiment.
[0111] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.5 mm to 31.5 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 6ED90 hex to address 79BDF hex)
allocated to the radius 30.5 mm to 31.5 mm of the first recording
layer 12 had been recorded was recorded in the control area 21 of
the second recording layer 14.
[0112] Subsequently, a host transmitted a command for performing
reproducing in a position of the radius 31 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30.5
to 31.5 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, by a command from the
controller 110, a focus of a laser beam of the optical head 52 was
moved to a position of the radius 30.5 mm of the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for reducing a laser beam output (reproducing power) from an
initial value 1.2 mW to 1.0 mW to the reproducing power setting
circuit 107. By such a series of operations or the like, a good
reproducing signal was obtained from the radius 31 mm which was a
desired area.
[0113] As described above, it was possible to check that when the
first recording layer 12 was in the recorded state, good
reproducing was carried out from the second recording layer 14 by
reducing the laser beam output.
Embodiment 3
[0114] Recording was tried on the second recording layer 14 by
using the medium 44 of the Embodiment 1, and the device 50 of the
embodiment.
[0115] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the first recording layer 12. In
this case, in accordance with the aforementioned procedure,
information indicating that addresses (address 69680 hex to address
7E2DF hex) allocated to the radius 30 mm to 32 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 formed in the inner periphery of the first recording layer
12.
[0116] Subsequently, a host transmitted a command for performing
recording in the radius 31.8 to 32.2 mm of the data recording area
22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 mm
to 32 mm of the first recording layer 12, and transmitted the
status data to the controller 110.
[0117] Next, since the radius 31.8 mm to 32.0 mm of the first
recording layer 12 was in a recorded state, that is, the area 27 of
the first recording layer stacked on an upper part of a recording
target part 26 was set in a mixed state when recording was
performed in the radius area of the second recording layer 14, the
controller 110 canceled the recording, and moved the recording
position to a position of the radius 34.8 mm which was an
alternative (substitute) area. Next, reproducing was performed
again in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is an unrecorded state in the radius
34.5 mm to 35.5 mm of the first recording layer 12, and transmitted
the status data to the controller 110. Subsequently, the controller
110 transmitted a command for setting a laser beam output
(recording power) to an initial value 12 mW to the recording power
setting circuit 106. By such a series of operations or the like,
good recording was carried out in the radius of 34.8 mm to 35.2 mm
which was an alternative (substitute) area.
[0118] As described above, it was possible to check that when the
area 27 of the first recording layer 12 was set in the mixed state,
good recording was carried out on the second recording layer 14 by
moving to the alternative (substitute) area to perform
recording.
Embodiment 4
[0119] Reproducing was tried from the second recording layer 14 by
using the medium 44 of the Embodiment 1, and the device 50 of the
embodiment.
[0120] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.5 mm to 31.5 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 6ED90 hex to address 79BDF hex)
allocated to the radius 30.5 mm to 31.5 mm of the first recording
layer 12 had been recorded was recorded in the control area 21 of
the second recording layer 14.
[0121] Subsequently, a host transmitted a command for performing
reproducing in the radius 30.3 mm to 30.7 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30.5
to 31.5 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, by a command from the
controller 110, a focus of a laser beam of the optical head 52 was
moved to a position of the radius 30.0 mm of the first recording
layer 12. Subsequently, pseudo data recording was performed in the
radius 30.0 mm to 30.5 mm. For the pseudo data recording, data
transmitted from the pseudo data generation circuit 105 to the
recording data processing circuit 104 was used.
[0122] Next, by a command from the controller 110, a focus of the
laser beam of the optical head 52 was moved to the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for reducing a laser beam output (reproducing power) from an
initial value 1.2 mW to 1.0 mW to the reproducing power setting
circuit 107. By such a series of operations or the like, a good
reproducing signal was obtained from the radius 30.3 mm to 30.7 mm
which was a desired area.
[0123] As described above, it was possible to check that when the
area 27 of the first recording layer 12 was in the mixed state,
good reproducing was carried out from the second recording layer 14
by recording the pseudo data in the unrecorded part.
Embodiment 5
[0124] Recording was tried on the second recording layer 14 by
using the medium 44 of the Embodiment 1, and the device 50 of the
embodiment.
[0125] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 31 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.5 mm to 31.5 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 6ED90 hex to address 79BDF hex)
allocated to the radius 30.5 mm to 31.5 mm of the first recording
layer 12 had been recorded was recorded in the control area 21 of
the second recording layer 14.
[0126] Subsequently, a host transmitted a command for performing
recording in a position of the radius 31 mm to 32 mm of the data
recording area 22 of the second recording layer 14. In accordance
with the aforementioned procedure, the device 50 first performed
reproducing in the control area 21 of the second recording layer
14. The recording layer management information.cndot.reproducing
circuit 109 recognized that a state is a recorded state in the
radius 30.5 to 31.5 mm of the first recording layer 12, and
transmitted the status data to the controller 110. Next, by a
command from the controller 110, a focus of a laser beam of the
optical head 52 was moved to a position of the radius 31.5 mm of
the first recording layer 12. Subsequently, pseudo data recording
was performed in the radius 31.5 mm to 32.0 mm. For the pseudo data
recording, data transmitted from the pseudo data generation circuit
105 to the recording data processing circuit 104 was used.
[0127] Next, by a command from the controller 110, a focus of the
laser beam of the optical head 52 was moved to the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for reducing a laser beam output (recording power) from an initial
value 12 mW to 10 mW to the recording power setting circuit 106. By
such a series of operations or the like, good recording was carried
out in the radius 31.0 mm to 32.0 mm which was a desired area.
[0128] As described above, it was possible to check that when the
area 27 of the first recording layer 12 was in the mixed state,
good recording was carried out on the second recording layer 14 by
recording the pseudo data in the unrecorded part.
Embodiment 6
[0129] A recording and reproducing operation was tried by using the
medium 44 of the Embodiment 1, and the device 50 of the embodiment
when there was an area having a defect in the first recording layer
12.
[0130] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the first recording layer 12.
Subsequently, reproducing was carried out in the radius 30 mm to 32
mm of the first recording layer 12. However, data reproducing was
difficult in the area of the radius 31.6 mm to 31.7 mm. In other
words, the area of the radius 31.6 mm to 31.7 mm was a defective
area. Thus, information indicating that addresses (address 69680
hex to address 7E2DF hex) allocated to the radius 30 mm to 32.0 mm
of the first recording layer 12 were recorded, and defective area
information indicating that the area of the radius 31.6 mm to 31.7
mm of the first recording layer 12 was the defective area, were
recorded in the control area 21 of the second recording layer
14.
[0131] Subsequently, a host transmitted a command for performing
recording in the radius 31.5 mm to 31.8 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 to
32 mm of the first recording layer 12 and the radius 31.6 mm to
31.7 mm of the first recording layer 12 is a defective area, and
transmitted the status data to the controller 110.
[0132] Next, since the radius 31.6 mm to 31.7 mm of the first
recording layer 12 was the defective area, the controller 110
cancelled recording on the second recording layer 14 near the area,
and moved the recording position to a position of a radius 34.5 mm
which was an alternative (substitute) area. Next, reproducing was
performed again in the control area 12 of the second recording
layer 14. The recording layer management
information.cndot.reproducing circuit 109 recognized that a state
is an unrecorded state in the radius 34.2 mm to 35.1 mm of the
first recording layer 12, and transmitted the status data to the
controller 110. The controller 110 transmitted a command for
setting a laser beam output (recording power) to an initial value
12 mW to the recording power setting circuit 106. By such a series
of operations or the like, good recording was carried out in the
radius 34.5 mm to 34.8 mm which was the alternative (substitute)
area.
[0133] As described above, it was possible to check that when there
was a defect in the first recording layer 12, good recording was
carried out on the second recording layer 14 by moving to the
alternative area.
Embodiment 7
[0134] FIG. 9 is a sectional view showing a constitution of an
optical information recording and reproducing medium of the
embodiment. The optical information recording and reproducing
medium of the embodiment is a write-once type medium 45, and has a
constitution similar to that of the medium 44 of the Embodiment 1
except for a difference of the constitution of the first and second
recording layers 12 and 14.
[0135] That is, as a first recording layer 12, a lower protective
film 12A made of ZnS--SiO.sub.2, a write-once type recording film
122 made of a TeSn based alloy, and an upper protective film 12C
made of ZnS--SiO.sub.2 were sequentially formed on a substrate 11
by sputtering method. As a second recording layer 14, a reflective
film 14D made of Al--Ti, an upper protective film 14C made of
ZnS--SiO.sub.2, a write-once type recording film 142 made of a TeSn
based alloy, and a lower protective film 14A made of ZnS--SiO.sub.2
were sequentially formed on a second substrate 18 by sputtering
method.
[0136] Optical characteristics of the medium of the embodiment were
measured. When a laser beam having a wavelength of 650 nm was
applied from the first substrate 17 side, in the case of the first
recording layer 12 alone, in an unrecorded case, a reflectance was
6% and a transmittance was 70%. In a recorded case, in an area in
which a write-once type recording mark was formed, average
reflectance was 8% and average transmittance was 60%. In the case
of the second recording layer 14 alone, a reflectance was 16% in an
unrecorded case, and an average reflectance was 21% in a recorded
case.
[0137] Under similar conditions, for the medium of the embodiment,
a reflectance from the second recording layer 14 was 7.8% when the
second and first recording layers 14 and 12 were in unrecorded
states. However, after the first recording layer 12 was recorded,
the reflectance from the second recording layer 14 was about 5.85%.
Additionally, a reflectance from the second recording layer 14 was
10.3% when the second recording layer 14 was recorded while the
first recording layer 12 was unrecorded. However, after the first
recording layer 12 was recorded, the reflectance from the second
recording layer 14 was about 7.6%.
[0138] Recording was tried on the medium of the embodiment by using
an optical head for a write-once type recording medium. A laser
beam wavelength of the optical head was 650 nm, and NA of a
condenser lens was 0.65. For the recording, the device 50 of the
embodiment described above with reference to FIG. 7 was used.
[0139] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the first recording layer 12. In
this case, in accordance with the aforementioned procedure,
information indicating that addresses (address 69680 hex to address
7E2DF hex) allocated to the radius 30 mm to 32 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 of the second recording layer 12.
[0140] Subsequently, a host transmitted a command for performing
recording in the radius 30.5 mm to 31.2 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 to
32 mm of the first recording layer 12, and transmitted the status
data to the controller 110. Next, by a command from the controller
110, a focus of a laser beam of the optical head 52 was moved to a
position of the radius 30.5 mm of the second recording layer 14.
Subsequently, the controller 110 transmitted a command for
increasing a laser beam output (recording power) from an initial
value 6 mW to 7 mW to the recording power setting circuit 106. By
such a series of operations or the like, good recording was carried
out for the radius 30.5 mm to 31.2 mm which was a desired area.
[0141] As described above, it was possible to check that in the
write-once type medium, when the first recording layer 12 was in
the recorded state, good recording was carried out on the second
recording layer 14 by increasing the laser beam output.
Embodiment 8
[0142] Reproducing was tried from the second recording layer 14 by
using the medium of the Embodiment 7, and the device 50 of the
embodiment.
[0143] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.5 mm to 31.5 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 6ED90 hex to address 79BDF hex)
allocated to the radius 30.5 mm to 31.5 mm of the first recording
layer 12 had been recorded was recorded in the control area 21 of
the second recording layer 14.
[0144] Subsequently, a host transmitted a command for performing
reproducing in a position of the radius 31 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30.5
to 31.5 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, by a command from the
controller 110, a focus of a laser beam of the optical head 52 was
moved to a position of the radius 30.5 mm of the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for increasing a laser beam output (reproducing power) from an
initial value 0.6 mW to 0.7 mW to the reproducing power setting
circuit 107. By such a series of operations or the like, a good
reproducing signal was obtained from the radius 31 mm which was a
desired area.
[0145] As described above, it was possible to check that in the
write-once type medium, when the first recording layer 12 was in
the recorded state, good reproducing was carried out from the
second recording layer 14 by increasing the laser beam output.
Embodiment 9
[0146] Recording was tried on the second recording layer 14 by
using the medium of the Embodiment 7, and the device 50 of the
embodiment.
[0147] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the first recording layer 12. In
this case, in accordance with the aforementioned procedure,
information indicating that addresses (address 69680 hex to address
7E2DF hex) allocated to the radius 30 mm to 32 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 of the second recording layer 12.
[0148] Subsequently, a host transmitted a command for performing
recording in the radius 31.8 to 32.2 mm of the data recording area
22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 mm
to 32 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, since the radius 31.8 mm
to 32.0 mm of the first recording layer 12 was in a recorded state,
that is, an area 27 of a recording target part 26 was set in a
mixed state when recording was performed in the radius area of the
second recording layer 14, the controller 110 canceled the
recording on the second recording layer 14 near the area, and moved
the recording position to a position of the radius 34.8 mm which
was an alternative (substitute) area.
[0149] Next, reproducing was performed again in the control area 21
of the second recording layer 14. The recording layer management
information.cndot.reproducing circuit 109 recognized that a state
is an unrecorded state in the radius 34.5 mm to 35.5 mm of the
first recording layer 12, and transmitted the status data to the
controller 110. Subsequently, the controller 110 transmitted
command data for setting a laser beam output (recording power) to
an initial value 6 mW to the recording power setting circuit. By
such a series of operations or the like, good recording was carried
out in the area 34.8 mm to 35.2 mm which was an alternative
(substitute) area.
[0150] As described above, it was possible to check that in the
write-once type medium, when the area 27 of the first recording
layer 12 was set in the mixed state, good recording was carried out
on the second recording layer 14 by moving to the alternative
(substitute) area to perform recording.
Embodiment 10
[0151] Reproducing was tried from the second recording layer 14 by
using the medium of the Embodiment 7, and the device 50 of the
embodiment.
[0152] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 32 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.5 mm to 31.5 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 6ED90 hex to address 79BDF hex)
allocated to the radius 30.5 mm to 31.5 mm of the first recording
layer 12 had been recorded was recorded in the control area 21 of
the second recording layer 14.
[0153] Subsequently, a host transmitted a command for performing
reproducing in the radius 30.3 mm to 30.8 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30.5
to 31.5 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, by a command from the
controller 110, a focus of a laser beam of the optical head 52 was
moved to a position of the radius 30.0 mm of the first recording
layer 12. Subsequently, pseudo data recording was performed in the
radius 30.0 mm to 30.5 mm. For the pseudo data recording, data
transmitted from the pseudo data generation circuit 105 to the
recording data processing circuit 104 was used.
[0154] Next, by a command from the controller 110, a focus of the
laser beam of the optical head 52 was moved to the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for increasing a laser beam output (reproducing power) from an
initial value 0.6 mW to 0.7 mW to the reproducing power setting
circuit 107. By such a series of operations or the like, a good
reproducing signal was obtained from the radius 30.3 mm to 30.8 mm
which was a desired area.
[0155] As described above, it was possible to check that in the
write-once type medium, when the area 27 of the first recording
layer 12 was in the mixed state, good reproducing was carried out
from the second recording layer 14 by recording the pseudo data in
the unrecorded part.
Embodiment 11
[0156] Recording was tried on the second recording layer 14 by
using the medium of the Embodiment 7, and the device 50 of the
embodiment.
[0157] To begin with, data was recorded in the data recording area
22 of a radius 30.0 mm to 31.0 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.5 mm to 31.5 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 6ED90 hex to address 79BDF hex)
allocated to the radius 30.5 mm to 31.5 mm of the first recording
layer 12 had been recorded was recorded in the control area 21 of
the second recording layer 14.
[0158] Subsequently, a host transmitted a command for performing
recording in a position of the radius 31.0 mm to 32.0 mm of the
data recording area 22 of the second recording layer 14. In
accordance with the aforementioned procedure, the device 50 first
performed reproducing in the control area 21 of the second
recording layer 14. The recording layer management
information.cndot.reproducing circuit 109 recognized that a state
is a recorded state of the radius 30.5 to 31.5 mm of the first
recording layer 12, and transmitted the status data to the
controller 110. Next, by a command from the controller 110, a focus
of a laser beam of the optical head 52 was moved to a position of
the radius 31.5 mm of the first recording layer 12. Subsequently,
pseudo data recording was performed in the radius 31.5 mm to 32.0
mm. For the pseudo data recording, data transmitted from the pseudo
data generation circuit 105 to the recording data processing
circuit 104 was used.
[0159] Next, by a command from the controller 110, a focus of the
laser beam of the optical head 52 was moved to the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for increasing a laser beam output (recording power) from an
initial value 6 mW to 7 mW to the recording power setting circuit
106. By such a series of operations or the like, good recording was
carried out in the radius 31.0 mm to 32.0 mm which was a desired
area.
[0160] As described above, it was possible to check that in the
write-once type medium, when the area 27 of the first recording
layer 12 was in the mixed state, good recording was carried out on
the second recording layer 14 by recording the pseudo data in the
unrecorded part.
Embodiment 12
[0161] An optical information recording and reproducing medium of
the embodiment is a concrete embodiment of the optical information
recording and reproducing medium of the second embodiment described
above with reference to FIG. 2. That is, as a substrate 11, a
polycarbonate resin substrate having an outer diameter of 120 mm,
an inner diameter of 15 mm, and a substrate thickness of 0.6 mm was
used. For the substrate 11, a substrate in which a wobbling groove
31 shown in FIG. 6 was formed beforehand by mastering was used. A
shape of the wobbling groove 31 had a depth of 35 nm and a track
pitch of 0.30 .mu.m. The wobbling groove 31 was spiral and formed
so as to achieve a wobbling frequency of 800 kHz when it was
rotated from the inner periphery to the outer periphery of the
substrate 11 at a linear velocity of 5.0 m/sec. A radius 22 mm to
24 mm of the substrate 11 was set as a control area 21, and a
radius 24 mm to 58 mm of its outside was set as a data recording
area 22. Pre-designated addresses were allocated to the control
area 21 and the data recording area 22 for each track of the
wobbling groove 31 in accordance with the aforementioned
predetermined method.
[0162] As a second recording layer 14, a reflective film 14D made
of Al--Ti, an upper protective film 14C made of ZnS--SiO.sub.2, a
phase change recording film 14B made of GeSbTe, and a lower
protective film 14A made of ZnS--SiO.sub.2 were sequentially formed
on the substrate 11 by sputtering method.
[0163] Next, as a spacer layer 13, an ultraviolet curing resin was
developed with a thickness of 15 .mu.m on the second recording
layer 14, and a wobbling groove 31 having a shape similar to that
of the wobbling groove 31 formed on a surface of the substrate 10
was formed on a surface of the ultraviolet curing resin by using a
stamper. A depth, a track pitch, and a wobbling frequency of the
wobbling groove 31 on the surface of the spacer layer 13, and a
constitution of the control area 21 and data recording area 22, and
the like were similar to those of the substrate 11. The ultraviolet
curing resin was irradiated with ultraviolet rays to be cured, and
then the stamper was removed.
[0164] Subsequently, as a first recording layer 12, an upper
protective film 12C made of ZnS--SiO.sub.2, a phase change
recording film 12B made of GeSbTe, and a lower protective film 12A
made of ZnS--SiO.sub.2 were sequentially formed on the spacer layer
13 by sputtering method.
[0165] Subsequently, as a cover layer 15, a polycarbonate cover
film having a thickness of 90 .mu.m was bonded on the second
recording layer 14 by an ultraviolet curing resin. In this case, a
thickness of adding together the cover film and the ultraviolet
curing resin was 95 .mu.m.
[0166] Subsequently, full surfaces of data recording areas of the
first and second recording layers 12 and 14 in which recording was
performed were initialized by using an initialization device. That
is, by setting a crystal state which was an initial state
equivalent to non-recording, the medium of the embodiment was
formed.
[0167] Optical characteristics of the medium of the embodiment were
measured. When a laser beam having a wavelength of 405 nm was
applied from the substrate 11 side, in the case of the first
recording layer 12 alone, reflectance for un-recorded crystal state
was 5% and transmittance was 60%. Reflectance for recorded
amorphous state was 13% and transmittance was 45%. In the case of
the second recording layer 14 alone, reflectance was 13% for
un-recorded crystal state, and reflectance was 35% for recorded
amorphous state.
[0168] Under similar conditions, for the medium 40, a reflectance
from the second recording layer 14 was 4.7% when the second and
first recording layers 14 and 12 were unrecorded. However, after
the first recording layer 12 was recorded, the reflectance from the
second recording layer 14 was about 3.6%. Additionally, a
reflectance from the second recording layer 14 was 12.6% when the
second recording layer 14 was recorded while the first recording
layer 12 was unrecorded. However, after the first recording layer
12 was recorded, the reflectance from the second recording layer 14
was about 9.7%.
[0169] Recording was tried on the medium of the embodiment by using
an optical head for a phase change recording medium. A laser beam
wavelength of the optical head was 405 nm, and NA of a condenser
lens was 0.85. For the recording, the device 50 of the embodiment
described above with reference to FIG. 7 was used.
[0170] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 31 mm of the first recording layer 12. In
this case, in accordance with the aforementioned procedure,
information indicating that addresses (address 168800 hex to
address 1A317F hex) allocated to the radius 30 mm to 31 mm of the
first recording layer 12 had been recorded was recorded in the
control area 21 of the second recording layer 14.
[0171] Subsequently, a host transmitted a command for performing
recording in the radius 30.3 mm to 30.7 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 to
31 mm of the first recording layer 12, and transmitted the status
data to the controller. Next, by a command from the controller 110,
the recording position was moved to a position of the radius 30.3
mm of the second recording layer 14. Subsequently, the controller
110 transmitted a command for increasing a laser beam output
(recording power) from an initial value 4 mW to 5 mW to the
recording power setting circuit 106. By such a series of operations
or the like, good recording was carried out for the radius 30.3 mm
to 30.7 mm which was a desired area.
[0172] As described above, it was possible to check that in the
medium 40 of the second embodiment, when the first recording layer
12 was in the recorded state, good recording was carried out on the
second recording layer 14 by increasing the laser beam output.
Embodiment 13
[0173] Reproducing was tried from the second recording layer 14 by
using the medium of the Embodiment 12, and the device 50 of the
embodiment.
[0174] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 31 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.2 mm to 30.8 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 174380 hex to address 1975FF
hex) allocated to the radius 30.2 mm to 30.8 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 of the second recording layer.
[0175] Subsequently, a host transmitted a command for performing
reproducing in a position of the radius 30.5 mm of the data
recording area 22 of the second recording layer 14. In accordance
with the aforementioned procedure, the device 50 first performed
reproducing in the control area 21 of the second recording layer
14. The recording layer management information.cndot.reproducing
circuit 109 recognized that a state is a recorded state in the
radius 30.2 to 30.8 mm of the first recording layer 12, and
transmitted the status data to the controller 110. Next, by a
command from the controller 110, a focus of a laser beam of the
optical head 52 was moved to a position of the radius 30.5 mm of
the second recording layer 14. The controller 110 transmitted a
command for increasing a laser beam output (reproducing power) from
an initial value 0.4 mW to 0.5 mW to the reproducing power setting
circuit 107. By such a series of operations or the like, a good
reproducing signal was obtained from the radius 30.5 mm which was a
desired area.
[0176] As described above, it was possible to check that in the
medium 40 of the second embodiment, when the first recording layer
12 was in the recorded state, good reproducing was carried out from
the second recording layer 14 by increasing the laser beam
output.
Embodiment 14
[0177] Recording was tried on the second recording layer 14 by
using the medium of the Embodiment 12, and the device 50 of the
embodiment.
[0178] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 31 mm of the first recording layer 12. In
this case, in accordance with the aforementioned procedure,
information indicating that addresses (address 168800 hex to
address 1A317F hex) allocated to the radius 30 mm to 31 mm of the
first recording layer 12 had been recorded was recorded in the
control area 21 of the second recording layer 12.
[0179] Subsequently, a host transmitted a command for performing
recording in the radius 30.8 mm to 31.2 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30 mm
to 31 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, since the radius 30.8 mm
to 31.0 mm of the first recording layer 12 was in a recorded state,
that is, an area 27 of a recording target part 26 was set in a
mixed state when recording was performed in the radius area of the
second recording layer 14, the controller 110 canceled the
recording on the second recording layer 14 near the area, and moved
the recording position to a position of the radius 32.0 mm which
was an alternative (substitute) area.
[0180] Next, reproducing was performed again in the control area 21
of the second recording layer 14. The recording layer management
information.cndot.reproducing circuit 109 recognized that a state
is an unrecorded state in the radius 32.0 mm to 32.4 mm of the
first recording layer 12, and transmitted the status data to the
controller 110. Subsequently, the controller 110 transmitted
command data for setting a laser beam output (recording power) to
an initial value 4 mW to the recording power setting circuit. By
such a series of operations or the like, good recording was carried
out in the radius of 32.0 mm to 32.4 mm which was an alternative
(substitute) area.
[0181] As described above, it was possible to check that in the
medium equivalent to the Embodiment 12, when the area 27 of the
first recording layer 12 was set in the mixed state, good recording
was carried out on the second recording layer 14 by moving to the
alternative (substitute) area to perform recording.
Embodiment 15
[0182] Reproducing was tried from the second recording layer 14 by
using the medium of the Embodiment 12, and the device 50 of the
embodiment.
[0183] To begin with, data was recorded in the data recording area
22 of a radius 30 mm to 31 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.2 mm to 30.8 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 174380 hex to address 1975FF
hex) allocated to the radius 30.2 mm to 30.8 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 of the second recording layer 14.
[0184] Subsequently, a host transmitted a command for performing
reproducing in the radius 30.0 mm to 30.4 mm of the data recording
area 22 of the second recording layer 14. In accordance with the
aforementioned procedure, the device 50 first performed reproducing
in the control area 21 of the second recording layer 14. The
recording layer management information.cndot.reproducing circuit
109 recognized that a state is a recorded state in the radius 30.2
to 30.4 mm of the first recording layer 12, and transmitted the
status data to the controller 110. Next, by a command from the
controller 110, a focus of a laser beam of the optical head 52 was
moved to a position of the radius 30.0 mm of the first recording
layer 12. Subsequently, pseudo data recording was performed in the
radius 30.0 mm to 30.2 mm. For the pseudo data recording, data
transmitted from the pseudo data generation circuit 105 to the
recording data processing circuit 104 was used.
[0185] Next, by a command from the controller 110, a focus of the
laser beam of the optical head 52 was moved to the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for increasing a laser beam output (reproducing power) from an
initial value 0.4 mW to 0.5 mW to the reproducing power setting
circuit 107. By such a series of operations or the like, a good
recording signal was obtained from the radius 30.0 mm to 30.4 mm
which was a desired area.
[0186] As described above, it was possible to check that in the
write-once medium, when the area 27 of the first recording layer 12
was in the mixed state, good reproducing was carried out from the
second recording layer 14 by recording the pseudo data in the
unrecorded part.
Embodiment 16
[0187] Recording was tried on the second recording layer 14 by
using the medium of the Embodiment 12, and the device 50 of the
embodiment.
[0188] To begin with, data was recorded in the data recording area
22 of a radius 30.0 mm to 30.5 mm of the second recording layer 14.
Next, data was recorded in the data recording area 22 of the radius
30.2 mm to 30.8 mm of the first recording layer 12. In this case,
in accordance with the aforementioned procedure, information
indicating that addresses (address 174380 hex to address 1975FF
hex) allocated to the radius 30.2 mm to 30.8 mm of the first
recording layer 12 had been recorded was recorded in the control
area 21 of the second recording layer 14.
[0189] Subsequently, a host transmitted a command for performing
recording in a position of the radius 30.5 mm to 31.0 mm of the
data recording area 22 of the second recording layer 14. In
accordance with the aforementioned procedure, the device 50 first
performed reproducing in the control area 21 of the second
recording layer 14. The recording layer management
information.cndot.reproducing circuit 109 recognized that a state
is a recorded state in the radius 30.5 to 30.8 mm of the first
recording layer 12, and transmitted the status data to the
controller 110. Next, by a command from the controller 110, a focus
of a laser beam of the optical head 52 was moved to a position of
the radius 30.8 mm of the first recording layer 12. Subsequently,
pseudo data recording was performed in the radius 30.8 mm to 31.0
mm. For the pseudo data recording, data transmitted from the pseudo
data generation circuit 105 to the recording data processing
circuit 104 was used.
[0190] Next, by a command from the controller 110, a focus of the
laser beam of the optical head 52 was moved to the second recording
layer 14. Subsequently, the controller 110 transmitted a command
for increasing a laser beam output (recording power) from an
initial value 4 mW to 5 mW to the recording power setting circuit
106. By such a series of operations or the like, good recording was
carried out in the radius 30.5 mm to 31.0 mm which was a desired
area.
[0191] As described above, it was possible to check that in the
write-once type medium, when the area 27 of the first recording
layer 12 was in the mixed state, good recording was carried out on
the second recording layer 14 by recording the pseudo data in the
unrecorded part.
[0192] In the Embodiments 12 to 16, the medium of the constitution
shown in FIG. 2, that is, the medium of the constitution in which
the thin cover layer was formed on the laser beam incident surface
and the substrate having a large thickness was formed on the side
opposed to the laser beam incident surface, was combined with the
high NA lens, that is, the condenser lens of NA 0.85 and the
semiconductor laser beam source of a wavelength 405 nm. However,
even in the combination of a medium having a wobbling groove formed
on a substrate of a thickness 0.6 mm with a condenser lens of NA
0.65 and a semiconductor laser beam source of a wavelength 405 nm,
effects similar to those of the results shown in the Embodiments 12
to 16 were confirmed.
[0193] According to the embodiments and the Embodiments, by
performing the reproducing in the control area 21 of the second
recording layer 14, the recording layer management information and
the defect management information regarding the data recording area
22 of the first recording layer 12 were checked. However, there is
no need to set great store by the reproduction in the control area
21 of the second recording layer 14. As long as the quickness or
the risk is not a problem, reproducing may be directly performed in
the control area 21 of the first recording layer 12.
[0194] The present invention has been described based on the
preferred embodiments. However, the optical information recording
and reproducing medium, the recording device, the recording and
reproducing device, the reproducing device, the recording method,
the recording and reproducing method, and the reproducing method of
the invention are not limited to the constitutions of the
embodiments. An optical information recording and reproducing
medium and the like variously modified and changed from the
constitutions of the foregoing embodiments are also within the
scope of the invention.
INDUSTRIAL APPLICABILITY
[0195] The present invention is suited to an optical information
recording and reproducing medium of a phase change type, a
write-once type or the like having a plurality of recording layers,
and a recording method, a recording and reproducing method, a
reproducing method, a recording device, a recording and reproducing
device, and a reproducing device of this optical information
recording and reproducing medium.
* * * * *