U.S. patent application number 11/949348 was filed with the patent office on 2008-03-27 for write-once disc, recording apparatus thereto, and method of reducing access time thereto.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Sung-hee Hwang, Jung-wan Ko, Kyun-geun Lee.
Application Number | 20080074960 11/949348 |
Document ID | / |
Family ID | 36123985 |
Filed Date | 2008-03-27 |
United States Patent
Application |
20080074960 |
Kind Code |
A1 |
Hwang; Sung-hee ; et
al. |
March 27, 2008 |
WRITE-ONCE DISC, RECORDING APPARATUS THERETO, AND METHOD OF
REDUCING ACCESS TIME THERETO
Abstract
A write-once disc, an apparatus for recording information
thereon, and a method of reducing access time thereto the
write-once disc including at least one record layer. The write-once
disc also includes at least one update area in which updated
predetermined information is recorded; and an access information
area in which location information regarding the updated
predetermined information, is recorded for a predetermined period.
Accordingly, it is possible to reduce an access time for reading
information updated in the write-once disc on which predetermined
information is updated and recorded on a new position.
Inventors: |
Hwang; Sung-hee; (Seoul,
KR) ; Ko; Jung-wan; (Gyeonggi-do, KR) ; Lee;
Kyun-geun; (Gyeonggi-do, KR) |
Correspondence
Address: |
STEIN, MCEWEN & BUI, LLP
1400 EYE STREET, NW
SUITE 300
WASHINGTON
DC
20005
US
|
Assignee: |
Samsung Electronics Co.,
Ltd.
Suwon-si
KR
|
Family ID: |
36123985 |
Appl. No.: |
11/949348 |
Filed: |
December 3, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10765954 |
Jan 29, 2004 |
|
|
|
11949348 |
Dec 3, 2007 |
|
|
|
Current U.S.
Class: |
369/30.04 |
Current CPC
Class: |
G11B 2220/20 20130101;
G11B 2020/10907 20130101; G11B 7/00736 20130101; G11B 20/1816
20130101; G11B 7/00745 20130101; G11B 7/0045 20130101; G11B 7/00375
20130101; G11B 2220/2537 20130101; G11B 27/36 20130101; G11B
2220/237 20130101; G11B 20/1217 20130101; G11B 2020/1893 20130101;
G11B 2220/218 20130101; G11B 27/329 20130101; G11B 20/1883
20130101; G11B 2020/1873 20130101; G11B 20/1879 20130101; G11B
2020/1295 20130101; G11B 2020/1275 20130101; G11B 2020/1278
20130101 |
Class at
Publication: |
369/030.04 |
International
Class: |
G11B 7/085 20060101
G11B007/085 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 28, 2003 |
KR |
2003-12868 |
Mar 3, 2003 |
KR |
2003-12952 |
Claims
1. A write-once disc with at least one record layer, comprising: a
recording condition area in which recording condition test data is
recorded; a temporary defect management area in which temporary
defect information and temporary defect management information are
recorded, the temporary defect management information comprising a
first pointer indicating an area in which the temporary defect
information is recorded, and a second pointer indicating an area in
which recording condition test data will be recorded next; and an
access information area in which location information regarding an
area in which updated predetermined information is recorded, is
recorded, wherein the location information comprises an address of
the area in which the temporary defect information is recorded and
an address of the area in which the recording condition test data
will be recorded next.
2. The disc of claim 1, wherein the location information is
recorded in the access information area several times.
3. The disc of claim 1, wherein the location information is
recorded in the access information area when the updated
predetermined information is recorded a predetermined number of
times.
4. An apparatus for recording data on a write-once disc with at
least one record layer, the write-once disc comprising a recording
condition area in which recording condition test data is recorded,
and a temporary defect management area in which temporary defect
information and temporary defect management information are
recorded, the temporary defect management information comprising a
first pointer indicating an area in which the temporary defect
information is recorded, and a second pointer indicating an area in
which the recording condition test data will be recorded next, the
apparatus comprising: a pickup which emits a light to transfer the
data with respect to the write-one disc; and a controller which
controls the pickup to record location information regarding an
area in which updated predetermined information is recorded, in an
access information area, wherein the location information comprises
an address of the area in which the temporary defect information is
recorded and an address of the area in which the recording
condition test data will be recorded next.
5. The apparatus of claim 4, wherein the location information is
recorded in the access information area several times.
6. The apparatus of claim 4, wherein the location information is
recorded in the access information area when the updated
predetermined information is recorded a predetermined number of
times.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/765,954, filed Jan. 29, 2004, which claims
the benefit of Korean Patent Application No. 2003-12868 filed on
Feb. 28, 2003, and of Korean Patent Application No. 2003-12952
filed on Mar. 3, 2003, in the Korean Intellectual Property Office,
the disclosures of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to recording information on
and/or reproducing information from a write-once disc, and more
particularly, to a write-once disc, an apparatus for recording
information thereon, and a method of reducing access time
thereto.
[0004] 2. Description of the Related Art
[0005] Unlike a rewritable disc, it is impossible to rewrite data
to a portion of a write-once disc where data has already been
recorded. That is, once the data is recorded on the write-once
disc, it is impossible to delete the data and record new data
thereon. Accordingly, a new portion of the write-once disc must be
allotted to update the already recorded data.
[0006] In general, since only last updated information on a disc is
available, a recording and/or reproducing apparatus first scans the
disc to detect the last updated information. The more information
to be updated, the longer the time required for scanning the disc
to obtain recent information from the disc. In particular, this
problem becomes more serious for a write-once disc, since whenever
information is updated, the updated information is recorded at
different portions of an area of the write-once disc unlike a
rewritable disc. If the size of the area where information is
updated is reduced to lessen disc scanning time, desired
information can be detected fast, but a number of times for
updating information is limited.
SUMMARY OF THE INVENTION
[0007] The present invention provides a write-once disc, and a
method of and apparatus for recording information on the write-once
disc in a data structure such that a disc access time for reading
updated information is reduced.
[0008] According to an aspect of the present invention, there is
provided a write-once disc with at least one record layer,
including at least one update area in which updated predetermined
information is recorded; and an access information area in which
location information regarding information, which is last updated
and recorded in the at least one update area, is recorded for a
predetermined period.
[0009] According to another aspect of the present invention, there
is provided a write-once disc with at least one record layer,
comprising a plurality of update areas in which predetermined
information is updated and sequentially recorded; and an access
information area in which location information regarding
information, which is last updated and recorded in the update
areas, is recorded per predetermined period. Here, location
information regarding information last updated is recorded in at
least one of the update areas.
[0010] According to yet another aspect of the present invention,
there is provided a method of reducing an access time for accessing
a write-once disc with at least one record layer, the method
comprising sequentially recording updated predetermined information
in at least one update area which is present in at least one of a
lead-in area, a data area, a lead-out area, and an outer area; and
recording location information regarding information, which is last
updated in the update area, in an access information area present
in at least one of the lead-in area, the data area, the lead-out
area, and the outer area per predetermined period.
[0011] According to still another aspect of the present invention,
there is provided a method of reducing access time for accessing a
write-once disc with at least one record layer, the method
comprising sequentially recording updated predetermined information
in a plurality of update areas which are present in at least one of
a lead-in area, a lead-out area, and an outer area; recording
location information regarding information, which is last updated
in at least one of the update areas, in one of the update areas;
and recording location information regarding the information, which
is last updated in one of the update areas, in an access
information area present in at least one of the lead-in area, the
lead-out area, and the outer area per predetermined period.
[0012] According to still another aspect of the present invention,
there is provided an apparatus for recording information on a
write-once disc with at least one record layer, the apparatus
comprising a recording/reading unit that records information on or
reads data from the write-once disc; and a controller that controls
the recording/reading unit to sequentially record updated
predetermined information in at least one update area of the
write-once disc, and record location information regarding
information, which is last updated in the at least one update area,
in an access information area of the write-once disc per
predetermined period.
[0013] According to still another aspect of the present invention,
there is provided an apparatus for recording information on a
write-once disc with at least one record layer, the apparatus
comprising a recording/reading unit that records information on/or
reads data from the write-once disc; and a controller that controls
the recording/reading unit to sequentially record updated
predetermined information in a plurality of update areas of the
write-once disc; record location information regarding information,
last updated in one of the update areas; and record location
information regarding information last updated in the updated area
in an access information area of the write-once disc per
predetermined period.
[0014] Additional aspects and/or advantages of the invention will
be set forth in part in the description which follows and, in part,
will be obvious from the description, or may be learned by practice
of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] These and/or other aspects and advantages of the invention
will become apparent and more readily appreciated from the
following description of the embodiments, taken in conjunction with
the accompanying drawings of which:
[0016] FIG. 1 is a block diagram of a recording apparatus according
to an embodiment of the present invention;
[0017] FIGS. 2A and 2B illustrate structures of a write-once disc
according to embodiments of the present invention;
[0018] FIG. 3 illustrates a data structure of a write-once disc
with an access information area and an update area, according to an
embodiment of the present invention;
[0019] FIG. 4 is a reference diagram illustrating recording of data
on a write-once disc, according to an embodiment of the present
invention;
[0020] FIGS. 5A through 5D are reference diagrams respectively
illustrating location information recorded in an access information
area of a write-once disc, according to embodiments of the present
invention;
[0021] FIG. 6 illustrates a data structure of location information
AA #i illustrated in FIGS. 4 and 5A through 5D;
[0022] FIG. 7 is a reference diagram illustrating recording of data
on a write-once disc, according to another embodiment of the
present invention;
[0023] FIG. 8 illustrates a data structure of information A #i
recorded in an update area A of FIG. 7;
[0024] FIG. 9 illustrates a data structure of a write-once disc
according to an embodiment of the present invention; and
[0025] FIG. 10 illustrates detailed diagrams for explaining
recording of data in a user data area and a spare area of a
write-once disc, according to an embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Reference will now be made in detail to the embodiments of
the present invention, examples of which are illustrated in the
accompanying drawings, wherein like reference numerals refer to the
like elements throughout. The embodiments are described below to
explain the present invention by referring to the figures.
[0027] FIG. 1 is a block diagram of a recording apparatus according
to an embodiment of the present invention. Referring to FIG. 1, the
recording apparatus includes a recording/reading unit 1, a
controller 2, and a memory 3. The recording/reading unit 1 records
data on a disc 100, which is an information storage medium
according to an embodiment of the present invention, and reads back
the data from the disc 100 to verify the accuracy of the recorded
data. The controller 2 controls the recording/reading unit 1 to
record data in a data structure according to the present invention.
More specifically, the controller 2 controls the recording/reading
unit 1 to sequentially record updated information in at least one
update area of the disc 100, and record location information, which
specifies a recording position of last updated information in the
update area, in an access information area of the disc 100 for a
predetermined period. In this embodiment, information is recorded
in the update area in recording units. The location information is
recorded in the access information area whenever a predetermined
number of recording operations end or a predetermined number of
logical or physical recording blocks of the update area are filled
with data. Alternatively, the location information is recorded when
at least one of a plurality of update areas is updated a
predetermined number of times or a number of times of updating
information in the plurality of update areas reaches a
predetermined number. Further, if the disc 100 includes the
plurality of update areas, the controller 2 controls the
recording/reading unit 1 to record location information, which
specifies a recording position of last updated information in at
least one update area, in the access information area. For disc
finalization, the controller 2 controls the recording/reading unit
to record the location information regarding information, which is
last recorded in the update area, in the access information
area.
[0028] Here, the recording operation is an operation determined
according to a user's intention or a recording work to be
performed. According to this embodiment, a recording operation
indicates a process in which the disc 100 is loaded into the
recording apparatus, data is recorded on the disc 100, and the disc
100 is taken out from the recording apparatus. When a user presses
the eject button (not shown) of the recording apparatus in order to
remove the disc 100 after recording of data, the controller 2
expects the recording operation to be terminated.
[0029] In particular, the controller 2 tests recording conditions
to adjust a laser power in the recording/reading unit 1, controls
the recording/reading unit to record data based on the test result,
and performs disc defect management. More specifically, to adjust
the laser power, the controller 2 tests recording conditions in at
least one logical or physical block of a test area, where recording
conditions are measured, in recording operation units. The test
area is included in the update area of the disc 100. Accordingly,
it is required to detect a position of the test area where
recording conditions will be tested next time. Data recorded for
test is recorded and updated in the test area. Also, for disc
defect management, the controller 2 uses a verify-after-write
method in which data is recorded on the disc 100 in predetermined
units of data and the accuracy of the recorded data is verified to
detect if an area of the disc 100 has a defect. In other words, the
controller 2 controls the recording/reading unit 1 to record user
data on the disc 100 in units of recording operations and verifies
the recorded user data to detect an area of the disc 100 in which a
defect exists. Thereafter, the controller 2 creates information
indicating the position of the area with the defect and stores the
created information in the memory 3. When the stored information
reaches a predetermined amount, the controller 2 controls the
recording/reading unit 1 to record the stored information as
temporary defect information in an update area, i.e., a temporary
defect management area (TDMA), of the disc 100. Next, the
controller 2 controls the recording/reading unit 1 to further
record temporary defect management information for managing the
temporary defect information in the TDMA. During each recording
operation, data is recorded and verified at least once; in general,
data is recorded and verified several times. Defect information
obtained using the verify-after-write method is temporarily stored
as temporary defect information in the memory 3. When the recording
operation ends, the controller 2 controls the recording/reading
unit 1 to rewrite the temporary defect information, which is stored
in the memory 3, to a defect management area (DMA) of the disc
100.
[0030] When the recording of data is completed, i.e., additional
data will not be recorded on the disc 100 (the disc 100 needs to be
finalized), and the controller 2 controls the recording/reading
unit 1 to rewrite the temporary defect information and the
temporary defect management information, stored in the TDMA, to the
DMA.
[0031] FIGS. 2A and 2B illustrate structures of the disc 100 of
FIG. 1, according to embodiments of the present invention. FIG. 2A
illustrates in detail a disc 100 having a single record layer L0
(single record layer disc). The disc 100 includes a lead-in area, a
data area, and a lead-out area. The lead-in area is located in an
inner part of the disc 100 and the lead-out area is located in an
outer part of the disc 100. The data area is present between the
lead-in area and the lead-out area and divided into a user data
area and a spare area. The user data area is an area where user
data is recorded, and the spare area is a replacement area for the
user data area having a defect, serving to compensate for loss in
the recording area due to the defect.
[0032] FIG. 2B illustrates a disc 100 having two record layers L0
and L1 (double record layer disc). A lead-in area, a data area, and
an outer area are sequentially formed from the inner part of the
first record layer L0 to its outer part. Also, an outer area, a
data area, and a lead-out area are sequentially formed from the
outer part of the second record layer L1 to its inner part. Unlike
the single record layer disc of FIG. 2A, the lead-out area is
present in the inner part of the disc 100 of FIG. 2B. That is, the
disc 100 of FIG. 2B has an opposite track path (OTP) in which data
is recorded starting from the lead-in area of the first record
layer L0 toward its outer area and continuing from the outer area
of the second record layer L1 to its lead-out area. The spare area
is allotted to each of the record layers L0 and L1.
[0033] In this embodiment, the spare areas are present between the
lead-out area and the user data area and between the user data area
and the outer area. However, if necessary, a portion of the user
data area may be used as another spare area, that is, more than one
spare area may be present between the lead-in area and the lead-out
area.
[0034] FIG. 3 illustrates a data structure of the disc 100 of FIGS.
2A and 2B, in which an access information area and update areas are
present in a lead-out area or an outer area, according to an
embodiment of the present invention. Referring to FIG. 3, if the
disc 100 is a single record layer disc, the access information area
is present in at least one of the lead-in area and the lead-out
area. If the disc 100 is a double record layer disc, the access
information area is present in at least one of the lead-in area,
the lead-out area, and the outer area. A plurality of the access
information areas may be formed in separate areas or may be formed
separately in the same area.
[0035] Further, when the disc 100 is a single record layer, at
least one update area is present in at least one of the lead-in
area and the lead-out area. When the disc 100 is a double record
layer, at least one update area is present in at least one of the
lead-in area, the lead-out area, and the outer area. FIG. 3
illustrates two update areas A and B in which information to be
updated is respectively recorded. In this embodiment, predetermined
information is updated and recorded in the update areas A and B in
recording operation units. A period for updating information may be
changed depending on characteristics of information to be recorded
or a user's desire. In the access information area, location
information regarding respective information that is last updated
in the update areas A and B is recorded per predetermined period.
In this embodiment, the location information is recorded in a
predetermined number of recording operation units or is recorded
whenever a predetermined number of logical or physical blocks are
filled with information. If necessary, only location information,
which specifies recording locations of information updated in parts
of a plurality of update areas, may be recorded in the access
information area.
[0036] For access time, a size of a block, which is a basic unit
for error correcting code (ECC), of the update area A is preferably
small. During a write operation, location information regarding the
location of information last recorded in at least another update
area is recorded whenever information recorded in the update area A
is recorded. When a total number of recording operations are
expected to be small according to characteristics of data to be
recorded or a user environment, a period of updating the location
information recorded in the access information area is determined
to be short. Otherwise, the period may be determined to be long. An
instant of time when the location information recorded in the
access information area is updated, may also be differently
determined.
[0037] During a read operation, information for accessing
information recorded in the updated areas is obtained by reading
location information last recorded in the access information area
while scanning the access information area starting from a start
thereof. For disc finalization, location information regarding
information last recorded in the respective updated areas is
recorded in the access information area.
[0038] In this embodiment, an update area is present in at least
one of the lead-in area, the lead-out area, and the outer area.
However, another update area may be further present in a user data
area, if necessary. In other words, predetermined information is
updated and recorded in an update area, and a location of the
update area is not limited.
[0039] FIG. 4 illustrates a method of recording information on the
disc 100, according to an embodiment of the present invention.
Referring to FIG. 4, information is updated n times and
sequentially recorded as A#1, A#2, . . . , A#n in an update area A,
and information is updated n times and sequentially recorded as
B#1, B#2, . . . , B#n in an update area B. Next, location
information AA#1 regarding the information A#n last updated and
recorded in the update area A and the information B#n last updated
and recorded in the update area B is recorded in an access
information area. The location information AA#1 may specify
physical or logical addresses of the information A#n and B#n. Next,
information is updated n times and sequentially recorded as A#n+1,
A#n+2, . . . , A#2n in the update area A, and information is
updated n times and sequentially recorded as B#n+1, B#n+2, . . . ,
B#2n in the update area B. Similarly, location information AA#2 is
recorded in the access information area. Alternatively, location
information AA#i recorded in the access information area may
include only location information regarding information last
updated and recorded in the update area A or B.
[0040] Further, once information is updated n times and recorded in
the update area A or B, location information may be recorded in the
access information area regardless of a number of updating
information recorded in the other update area B or A. Therefore,
when a number of times of updating the information recorded in the
update areas A and B is n, the location information may be recorded
in the access information area.
[0041] FIGS. 5A through 5D illustrate location information recorded
in an access information area, according to embodiments of the
present invention. Referring to FIG. 5A, the location information
is repeatedly recorded in the access information area. More
specifically, first location information AA#1 is recorded at a
start of the access information area, so that physical or logical
addresses increase. Next, a copy of the first location information
AA#1 is recorded. Next, second location information AA#2 is
recorded, and then, a copy of the second location information AA#2
is recorded. Recording the same information twice increases the
reliability and robustness of information. The number of times of
recording the same information may be more than twice and the same
information may be recorded using an interleaving method.
[0042] Referring to FIG. 5B, as compared to FIG. 5A, location
information is repeatedly recorded in the access information area
but the sequence of recording the location information is not the
same. More specifically, first location information AA#1 is
recorded starting from an end of the access information area, so
that physical or logical addresses decrease. Next, a copy of the
first location information AA#1 is recorded, and then, second
location information AA#2 is recorded. Next, a copy of the second
location information AA#2 is recorded. Recording the same
information twice increases the reliability and robustness of
information. Similarly, the number of times of recording the same
information may be more than twice and the same information may be
recorded using an interleaving method.
[0043] The access information area of FIG. 5C is physically or
logically divided into two sub areas. In a first sub area, first
location information AA#1 and second location information AA#2 are
sequentially recorded, so that physical or logical addresses
increase. In a second sub area, a copy of the first location
information AA#1 and a copy of the second location information AA#2
are sequentially recorded. Regarding a sequence of recording the
information, the first location information AA#1, the copy of the
first location information AA#1, the second location information
AA#2, and the copy of the second location information AA#2 are
sequentially recorded. In this embodiment, the original information
and a copy thereof are recorded in different areas, thereby
increasing the reliability and robustness of information.
Alternatively, the access information area may be divided into
three ore more sub areas, and location information may be recorded
at least three times.
[0044] As compared to FIG. 5C, the access information area of FIG.
5D is physically or logically divided into two sub areas, but the
sequence of recording location information is not the same. More
specifically, first location information AA#1 and second location
information AA#2 are sequentially recorded in a first sub area, so
that physical or logical addresses decrease. Also, a copy of the
first location information AA#1 and a copy of the second location
information AA#2 are sequentially recorded in a second sub area, so
that physical or logical addresses decrease. The sequence of
recording the information is the same as illustrated in FIG. 5C.
That is, the first location information AA#1, the copy of the first
location information AA#1, the second location information AA#2,
and the copy of the second location information AA#2 are
sequentially recorded. The original information and a copy thereof
are recorded in different areas, thereby increasing the reliability
and robustness of information. Alternatively, the access
information area may be divided into three ore more sub areas, and
location information may be recorded at least three times.
[0045] FIG. 6 illustrates a data structure of location information
AA#i as shown in FIG. 4 and FIGS. 5A through 5D. Referring to FIG.
6, the location information AA#i contains an identifier, an access
pointer to an update area A, and an access pointer to an update
area B. The access pointer to the update area A points to a
recording position of information last updated and recorded in the
update area A. The access pointer to the update area B points to a
recording position of information last updated and recorded in the
update area B. For instance, an access pointer indicates a starting
address of last recorded information.
[0046] FIG. 7 illustrates a method of recording information on the
disc 100, according to another embodiment of the present invention.
Referring to FIG. 7, as shown in FIG. 4, predetermined information
is updated n times and sequentially recorded as A#1, A#2, . . . ,
A#n in an update area A, and predetermined information is updated n
times and sequentially recorded as B#1, B#2, . . . , B#n in an
update area B. Next, location information AA#1 regarding
information A#n last updated and recorded in the update area A and
information B#n last updated and recorded in the update area B is
recorded in an access information area. The location information
AA#1 may specify physical or logical addresses of the information
A#n and B#n. Next, predetermined information is updated n times and
sequentially recorded as A#n+1, A#n+2, . . . , A#2n in the update
area A, and predetermined information is updated n times and
sequentially recorded as B#n+1, B#n+2, . . . , B#2n in the update
area B. Next, location information AA#2 regarding information A#2n
last updated and recorded in the update area A and information B#2n
last updated and recorded in the update area B is recorded in the
access information area. Alternatively, location information AA#i
recorded in the access information area may include only location
information regarding last updated information recorded in the
update area A or B.
[0047] The information A#1, A#2, . . . , A#n+1, . . . , A#2n
further include location information specifying location of last
updated information recorded in the update area B. For instance,
the location information included in the information A#n+1, which
is recorded in the update area A, points to a recording position of
the corresponding information B#n+1 recorded in the update area B.
For this reason, whenever the update area B is updated, the update
area A must also be updated. For instance, sometimes the
information A#1, A#2, . . . , A#n+1, . . . , A#2n need to be
updated although there is no change therein, only because the
information recorded in the update area B changes. In a worst-case
scenario, when instants when updating a plurality of update areas
are different from one another, and a recording position of last
updated information is recorded in the update area A whenever
information recorded in update areas other than the update area A
is updated, a size of the update area A is required to be the same
as or larger than a sum of sizes of the other update areas. To
prevent such a problem, instants when updating the other update
areas are preferably the same to minimize the size of the update
area A. Also, after recording updated information in the other
update areas, the information recorded in the update area A, which
is updated, and location information regarding at least one
information recorded in the other update areas are recorded in the
update area A. Information is recorded in the update area A after
completing recording information in the other update areas, since a
predetermined recording position of last updated information in the
other update areas can be changed. When a position of recording
last updated information in the update area B has been determined
and location information regarding the last updated information is
recorded in the update area A, if an ECC error occurs in the update
area B after recording the last updated information in the update
area B, a position of the last updated information in the update
area B may change.
[0048] FIG. 8 illustrates a data structure of information A#i
recorded in the update area A of FIG. 7. Referring to FIG. 8, the
information A#i includes information regarding itself and a pointer
pointing to a location of corresponding information B#i recorded in
the update area B of FIG. 7.
[0049] FIG. 9 illustrates a structure of the disc 100 of FIG. 1,
according to an embodiment of the present invention. For
convenience, FIG. 9 illustrates the disc 100 as a single record
layer disc. Referring to FIG. 9, a lead-in area of the disc 100
includes an access information area, a defect management area
(DMA), a temporary DMA (TDMA), and a recording condition test area.
A lead-out area of the disc 100 includes at least one of an access
information area, a DMA, a TDMA, and a recording condition test
area. That is, the access information area, the DMA, the TDMA, and
the recording condition test area may be present in at least one of
the lead-in area and the lead-out area. If the disc 100 is a double
record layer disc, an access information area, a DMA, a TDMA, and a
recording condition test area are included in each of a lead-in
area and a lead-out area positioned in an inner part of the disc
100. Also, an access information area, a DMA, a TDMA, and a
recording condition test area are included in each of a lead-in
area and a lead-out area positioned in an outer part of the disc
100.
[0050] Here, the TDMA and the recording condition test area
correspond to the update areas A and B of FIG. 3, 4, or 7. In the
access information area, location information regarding temporary
management information updated and recorded in the TDMA, and
location information regarding a portion of the recording condition
test area where recording conditions are last tested are recorded.
The temporary management information includes temporary defect
information and temporary defect management information. The
location information regarding a portion of the recording condition
test area may specify a start address of a portion of the recording
condition test area where recording conditions will be tested next
time. Alternatively, location information regarding information
recorded in the TDMA or the recording condition test area may be
selectively recorded in the access information area. In the TDMA,
the location information regarding a portion of the recording
condition test area where recording conditions are last tested is
recorded.
[0051] In this embodiment, a recording apparatus tests recording
conditions in the recording condition test area for every recording
operation, records information on the disc 100 based on the test
result, and records temporary management information in the TDMA
whenever a recording operation ends. Thus, information recorded in
the TDMA and information in the recording condition test area are
updated in recording operation units. Also, location information
regarding the recording condition test area is recorded together
with the temporary management information in the TDMA.
[0052] In general, information regarding a structure of a disc on
which disc defect management is performed, whether the disc defect
management is performed or not, a location and information
regarding a defect, and a size and location of a spare area are
recorded in the DMA.
[0053] When the disc 100 is loaded into a recording/reading
apparatus such as that shown in FIG. 1, the apparatus generally
reads data from a lead-in area and/or a lead-out area of the disc
100 to determine how to manage the disc 100 and to record data on
or read data from the disc 100. However, if the amount of data
recorded in the lead-in area and/or the lead-out area increases, a
longer time is required for preparing the recording or reproducing
of data after the loading of the disc 100. To solve this problem or
for other reasons, the present invention adopts temporary defect
management information and temporary defect information that are to
be recorded in a TDMA. The TDMA is allotted to the lead-in area
and/or the lead-out area of a disc, being separated from the DMA.
For disc finalization, temporary management information, including
temporary defect information and temporary defect management
information, which is last recorded in the TDMA, is recorded in the
DMA. That is, when additional information will not be recorded,
that is, disc finalization is required, only last recorded
information of the temporary defect management information and
temporary defect information, which have been updated several
times, are rewritten to the DMA. Thus, the recording/reading
apparatus can read defect management information fast from the disc
100 just by reading the last recorded defect management
information, thereby enabling fast initializing of the disc
100.
[0054] In this embodiment, since the disc defect management is
performed using linear replacement, the temporary defect
information includes information indicating the position of an area
of the disc 100 having a defect and information indicating the
position of an area of the disc 100 that is replacement for the
area having the defect. The temporary defect management information
is used to manage the temporary defect information and includes
information indicating the position of the disc 100 where the
temporary defect information is recorded.
[0055] In this embodiment, the temporary defect information and
temporary defect management information are recorded every time
when a recording operation ends. In the TDMA, information regarding
a defect, which occurs in data recorded during recording operation
#1, and information regarding a replacement area are recorded as
temporary defect information #1, and information regarding a
defect, which occurs in data recorded during recording operation
#2, and information regarding a replacement area are recorded as
temporary defect information #2. Further, in the TDMA, management
information for managing temporary defect information #1, #2, . . .
is recorded as temporary defect management information #1, #2, . .
. . The management information specifies recording positions of the
temporary defect information #1, #2, . . . .
[0056] When additional data cannot be recorded in the data area or
a user does not desire to record additional data therein, i.e.,
disc finalization is required, temporary defect information
recorded in a temporary defect information area and temporary
defect management information recorded in a temporary defect
management information area are rewritten to the DMA. For disc
finalization, the last recorded temporary defect information #1,
#2, . . . , #i is read and rewritten to the DMA.
[0057] FIG. 10 is a detailed reference diagram illustrating
recording of data in a user data area A and a spare area B,
according to an embodiment of the present invention.
[0058] Data can be processed in sector units or clusters. A sector
denotes a minimum unit of data that can be managed in a file system
of a computer or in an application, and a cluster denotes a minimum
unit of data that can be physically recorded on a disc at once. In
general, one or more sectors constitute a cluster.
[0059] There are two types of sectors: a physical sector and a
logical sector. The physical sector is an area on a disc where a
sector of data is to be recorded. An address for detecting the
physical sector is called a physical sector number (PSN). The
logical sector is a unit in which data can be managed in a file
system or an application. An address for detecting the logical
sector is called a logical sector number (LSN). A disc
recording/reading apparatus such as that in FIG. 1 detects the
recording position of data on a disc using a PSN. In a computer or
an application for recording or reproducing data, the entire data
is managed in units of LSNs and the position of data is detected
using an LSN. LSNs and PSNs are mapped by a controller of the
recording/reading apparatus, based on whether the disc 100 contains
a defect and an initial recording position of data.
[0060] Referring to FIG. 10, A denotes a user data area and B
denotes a spare area in which PSNs are sequentially allocated to a
plurality of sectors (not shown). In general, each LSN corresponds
to at least one PSN. However, since LSNs are allocated to
non-defective areas, including replacements recorded in the spare
area, the correspondence between the PSNs and the LSNs is not
maintained when a disc has a defective area, even if the size of a
physical sector is the same as that of a logical sector.
[0061] In the user data area A, user data is recorded either in a
continuous recording mode or a random recording mode. In the
continuous recording mode, user data is recorded sequentially and
continuously. In the random recording mode, user data is randomly
recorded. In the data area A, sections 1 through 7 denote
predetermined units of data in which the verify-after-write method
is performed.
[0062] When the disc 100 is loaded into the recording/reading
apparatus, the apparatus tests recording conditions in a recording
condition test area of the disc 100, adjusts a laser power based on
the test result, and records information on the disc 100. As
described above, once recording conditions are tested in a portion
of the recording condition test area, the portion becomes
unavailable, and thus, another portion will be used the next time
for testing the recording conditions.
[0063] The recording apparatus records user data in section 1,
returns to the start of section 1, and checks if the user data is
appropriately recorded or a defect exists in section 1. If a defect
is detected in a portion of section 1, the portion is designated as
defect #1. The user data recorded in defect #1 is also recorded on
a portion of the spare area B. Here, the portion of the spare area
B in which data recorded in defect #1 is rewritten is called
replacement #1. Next, the recording apparatus records user data in
section 2, returns to the start of section 2, and checks whether
the data is properly recorded or a defect exists in section 2. If a
defect is detected in a portion of section 2, the portion is
designated as defect #2. Likewise, replacement #2 corresponding to
defect #2 is formed in the spare area B. Further, defect #3 and
replacement #3 are designated in section 3 of the user data area A
and the spare area B, respectively. In section 4, a defect does not
occur and a defective area is not designated.
[0064] The recording apparatus records information regarding defect
#1, #2, and #3 occurring in sections 1 through 4 as temporary
defect information TDFL #1 in a TDMA, when recording operation #1
is expected to end, after the recording and verifying of data to
section 4, i.e., when a user presses the eject button of a
recording apparatus or recording of user data allocated in a
recording operation is complete. Also, management information for
managing temporary defect information TDFL #1 is recorded as
temporary defect management information TDDS #1 in the TDMA. Also,
location information regarding a portion of the recording condition
test area in which a next test will be performed is further
recorded in the TDMA.
[0065] When the disc 100 is again loaded, recording operation #2
starts, recording conditions are measured in the recording
condition test area, and data is recorded on the disc 100 based on
the measuring result. More specifically, during recording operation
#2, data is recorded in sections 5 through 7 and defects #4 and #5
and replacements #4 and #5 are formed in the user data area A and
the spare area B, respectively, as explained for sections 1 through
4. If recording operation #2 is expected to end, the recording
apparatus records information regarding defects #4 and #5 as
temporary defect information TDFL #2. Thereafter, management
information for managing the temporary defect information TDFL #2
is recorded as temporary defect management information TDDS #2 in
the TDMA. Also, location information regarding a portion of the
recording condition test area in which a next test will be
performed is further recorded in the TDMA. When a predetermined
number of recording operations are performed as described above,
location information regarding last recorded temporary management
information recorded in the TDMA, and location information
regarding a portion of the recording condition test area where
recording conditions will be performed, are recorded in an access
information area of the disc 100. The temporary management
information includes temporary defect information and defect
management information.
[0066] According to the present invention, an access time for the
disc 100 can be reduced as described below.
[0067] If ECC is performed in block units and reproduction time of
a block is 1, data recording is performed in block units that are
also ECC units. When data recording is performed in update areas A,
B, and C according to a recording operation and as a result, the
amount of information to be updated exceeds a block, the access
information area is very helpful. When information to be updated
can be recorded within a block, a number of times of performing
recording operations is equivalent to a number of blocks used. In
this case, it is easy to estimate a recording position of
information updated.
[0068] When information to be updated according to a recording
operation can be recorded within a block, the information is
updated in a following update area A, B, or C whenever a following
number of recording operations are performed:
[0069] update area A: 1000 blocks, a number of recording
operations=a
[0070] update area B: 1000 blocks, a number of recording
operations=b
[0071] update area C: 1000 blocks, a number of recording
operations=c
[0072] In this case, a time for obtaining desired information from
the respective update areas A, B, and C depends on whether the
access information is present or not in the disc 100, as
follows:
[0073] when the access information area is present:
(a+b+c)/30+(a+b+c) %30
[0074] (% indicates a modular operation)
[0075] when the access information area is not present: a+b+c
[0076] In conclusion, the time for obtaining desired information
from the respective update areas A, B, and C is the same regardless
of the inclusion of the access information area, until a recording
operation is performed thirty times, for example. However, once a
number of times of performing the recording operation is more than
30, a time required to reproduce information from twenty nine
blocks can be saved when the recording operation is further
performed thirty times. If a recording operation is performed 299
times in an update area, it is possible to save a time required to
reproduce information from 260 blocks, i.e., 9*29-1=260. In other
words, if the disc 100 does not include the access information
area, the time required to reproduce information from 299 blocks is
spent accessing an update area and scanning and obtaining new
information from the update area. However, if the disc 100 includes
the access information area, the time required to reproduce
information from only 39 blocks is spent. Accordingly, the
inclusion of the access information area into the disc 100 causes a
reduction in a time for obtaining recent information.
[0077] As described above, according to the present invention, it
is possible to minimize an access time for accessing a write-once
disc, on which predetermined information is updated and recorded at
a new position, so as to read the updated information.
[0078] Although a few embodiments of the present invention have
been shown and described, it would be appreciated by those skilled
in the art that changes may be made in this embodiment without
departing from the principles and spirit of the invention, the
scope of which is defined in the claims and their equivalents.
* * * * *