U.S. patent application number 13/540364 was filed with the patent office on 2012-11-29 for mold for optical device with anti-reflection structure, method for producing the same, and optical device.
This patent application is currently assigned to NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY. Invention is credited to Kazuma Kurihara, Takayuki Shima, Junji Tominaga.
Application Number | 20120300305 13/540364 |
Document ID | / |
Family ID | 39603841 |
Filed Date | 2012-11-29 |
United States Patent
Application |
20120300305 |
Kind Code |
A1 |
Kurihara; Kazuma ; et
al. |
November 29, 2012 |
MOLD FOR OPTICAL DEVICE WITH ANTI-REFLECTION STRUCTURE, METHOD FOR
PRODUCING THE SAME, AND OPTICAL DEVICE
Abstract
A process for producing through simple operations a molding die
for optical device having an antireflective structure of nano-order
microscopic uneven plane on a substratum surface. The molding die
for optical device having microscopic uneven plane (antireflective
structure die plane) on a surface of substratum is produced by a
process comprising forming one or more etching transfer layers on
substratum; forming thin film for formation of semisperical
microparticles on the etching transfer layers; causing the thin
film to undergo aggregation, or decomposition, or nucleation of the
material by the use of any of thermal reaction, photoreaction and
gas reaction or a combination of these reactions so as to form
multiple semispherical islandlike microparticles; and using the
multiple island like microparticles as a protective mask, carrying
out sequential etching of the etching transfer layers and
substratum by reactive gas to thereby form a conical pattern on the
microscopic surface of the substratum.
Inventors: |
Kurihara; Kazuma;
(Tsukuba-shi, JP) ; Shima; Takayuki; (Tsukuba-shi,
JP) ; Tominaga; Junji; (Tsukuba-shi, JP) |
Assignee: |
NATIONAL INSTITUTE OF ADVANCED
INDUSTRIAL SCIENCE AND TECHNOLOGY
Tokyo
JP
|
Family ID: |
39603841 |
Appl. No.: |
13/540364 |
Filed: |
July 2, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12515188 |
May 15, 2009 |
8226837 |
|
|
PCT/JP2007/069279 |
Oct 2, 2007 |
|
|
|
13540364 |
|
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Current U.S.
Class: |
359/601 |
Current CPC
Class: |
G02B 1/118 20130101;
Y10T 428/24355 20150115; B29C 45/00 20130101; B29C 33/42
20130101 |
Class at
Publication: |
359/601 |
International
Class: |
G02B 5/00 20060101
G02B005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 15, 2006 |
JP |
2006-308842 |
Apr 19, 2007 |
JP |
2007-110068 |
Claims
1.-9. (canceled)
10. An optical device comprising: a nano pattern having a nano
structure of a fine depressed and elevated surface formed on a
surface of a substrate and arranged randomly.
11. The optical device according to claim 10, wherein the nano
pattern of the optical device with the nano structure is
constructed in such a manner as to hold an interval of a wavelength
or less of a light source.
12. The optical device according to claim 10, wherein the nano
pattern includes a plurality of island-like particles having an
average particle size in a range of 5 nm to 1000 nm, and wherein an
average interval between adjacent island-like particles is in a
range of 10 nm to 2000 nm.
13. The optical device according to claim 12, wherein the nano
pattern of the optical device with the nano structure is
constructed in such a manner as to hold an interval of a wavelength
or less of a light source.
14. The optical device according to claim 10, wherein the nano
pattern is produced by the steps: forming a thin film comprising a
thin film material; and causing aggregation or nucleation of the
thin film material to form a plurality of island-like fine
particles composed of the film by using a heat reaction or a
photoreaction.
15. The optical device according to claim 14, wherein the nano
pattern of the optical device with the nano structure is
constructed in such a manner as to hold an interval of a wavelength
or less of a light source.
16. An optical device, comprising: a nano pattern having a nano
structure of a fine depressed and elevated surface formed on a
surface of a substrate and arranged with an irregular size and at
an irregular distance.
17. The optical device according to claim 16, wherein the nano
pattern of the optical device with the nano structure is
constructed in such a manner as to hold an interval of a wavelength
or less of a light source.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional of U.S. patent application
Ser. No. 12/515,188, filed May 15, 2009, which is a national stage
of International Application No. PCT/JP2007/069279, filed Oct. 2,
2007, which claims priority from Japanese Patent Application Nos.
2006-308842 and 2007-110068, filed Nov. 15, 2006, and Apr. 19,
2007, respectively, the contents of all of which are incorporated
herein by reference in their entirety.
TECHNICAL FIELD
[0002] The present invention relates to a mold for an optical
device such as a light emitting device, a photo acceptance device
and an anti-reflection coating with an anti-reflection structure, a
method for producing the same and an optical device.
BACKGROUND ART
[0003] Conventionally, an optical device composed of glass or the
like is subjected to surface treatment for reducing return light by
surface reflection and for increasing transmitted light. As a
specific method of this surface treatment, there is known a method
of forming fine and dense depressions and elevations on a surface
of the optical device.
[0004] In a case of thus forming the depressions and elevations in
a periodic pattern on the surface of the optical device, light is
diffracted when the light transmits through the surface of the
optical device to greatly reduce straight components of the
transmitted light. However, when the depressions and elevations
formed on the surface of the optical device is formed in a
rectangular shape in such a manner that a pitch thereof is shorter
than a wavelength of the transmitting light, the light is not
diffracted. Therefore, it is possible to obtain an anti-reflection
effect effective to the light with a single wavelength
corresponding to the pitch, a depth or the like of the depressions
and elevations.
[0005] Furthermore, it is known to be able to obtain an
anti-reflection effect also to light with a wide range of
wavelength by forming the depressions and elevations to be not in a
rectangular shape, but in a so-called conical shape (conical
pattern)in which the ratio of the crest-side volume by the material
of the optical device to trough-side volume by air continuously
varies (for example, refer to Patent Document 1 and Patent Document
2).
[0006] For carrying out a structure with anti-reflection to such a
wide range of wavelengths, a fine pattern having less than the
wavelength is required. Accordingly, there is known a method of
using an electronic beam lithography technology for producing such
a fine structure. This method is a method in which after coating a
substrate with electron resist, the electron beam is used to
perform patterning thereon, and reflective etching is used to etch
the substrate.
[0007] Furthermore, it is known that organic colloid is used to
produce a nano periodic structure, thus obtaining an
anti-reflection structure (for example, refer to Patent Document
3). The producing method using the organic colloid is a method in
which the organic colloid is mixed into a solution, the colloid is
coated on the surface of the substrate and a structure is produced
by reflective etching based upon colloid beads in such a manner as
to form a fine structure with a wavelength or less as a target,
thus forming the anti-reflection structure.
[0008] Patent Document 1: Japanese Patent Application Laid-Open No.
2001-272505
[0009] Patent Document 2: Japanese Patent Application Laid-Open No.
2006-243633
[0010] Patent Document 3: Japanese Patent Application Laid-Open No.
2005-331868
DISCLOSURE OF THE INVENTION
Problem to be Solved by the Invention
[0011] However, since the method of producing the anti-reflection
structure using the electron irradiation device requires a scan
with the electronic beams for patterning, the drawing throughput is
extremely slow to need time for the pattern formation. In
consequence, there occurs the problem with an increase in cost for
applying it to the optical device with an increased area.
[0012] Furthermore, the method of producing the anti-reflection
structure using the organic colloid as a protection mask can form a
periodic nano structure with a large area at a high speed, but it
is difficult to uniformly form the organic colloid on the large
area and also to form a single uniform layer.
[0013] Further, since the method of producing the anti-reflection
structure using the organic colloid as the protection mask requires
coating of the organic materials dispersed in the liquid, in a case
where the coating is applied to a structure with an complex
structure, there occur variations in film thickness of the organic
materials to be coated, thereby occurring the problem with
degradation of optical properties.
[0014] The present invention has an object of solving the above
problem and an issue of the present invention is in a point of
carrying out a mold for an optical device with the following nano
structure, a mold for the nano structure, a method of producing the
mold for the optical device with the nano structure and the mold
for the nano structure, and an optical device with the nano
structure.
[0015] (1) A mold for an optical device according to the present
invention can produce an optical device including a uniformly
stable nano structure and including an anti-reflection structure
with an anti-reflection effect in a wider wavelength band region
and with little dependency on an incident angle, on a surface of
the optical device formed of a structure with a large area and a
complex shape.
[0016] (2) A method of producing a mold for an optical device
according to the present invention is a method of being capable of
producing it with a fewer steps and with only dry processes in high
productivity.
[0017] (3) The optical device of the present invention is an
optical device including a nano pattern having a nano structure of
a fine depressed and elevated surface formed on the surface of a
substrate and arranged at a random, preferably this nano pattern
being constructed in such a manner as to hold an interval having a
wavelength or less of a light source.
Means for Solving the Problem
[0018] The present invention is, for solving the above problem, a
method of producing a mold for an optical device for molding the
optical device with an anti-reflection structure of a fine
depressed and elevated surface formed on a surface of a substrate,
and provides the method of producing the mold for the optical
device with the anti-reflection structure comprising forming one or
more etching transfer layers on the substrate, forming a thin film
to form island-like fine particles on the etching transfer layer,
using any one of a thermal reaction, a photoreaction, a chemical
reaction or a combination of these reactions to cause aggregation,
decomposition, or nucleation of a thin film material, thereby
forming plurality of island-like fine particles on the thin film,
using the plurality of the island-like fine particles as a
protection mask, carrying out etching of the etching layer and the
substrate in order, and forming an elevation pattern on the fine
surface of the substrate.
[0019] It is preferable that the plurality of the island-like fine
particles each have a size in the order of nano meters and form a
nano pattern in such a manner as to be arranged at a random while
holding an interval having a wavelength or less of light to be
reflected as a target, with each other.
[0020] According to an embodiment, a material of the thin film is
made of a material containing silver, gold, platinum, or palladium
as a main component, or an oxide or a nitride containing any one of
silver, gold, platinum, palladium, tungsten, bismuth, and tellurium
as a main component.
[0021] According to an embodiment, the island-like fine particle
has an average particle size of 5 nm to 1000 nm and an average
interval between the island-like fine particles is in a range of 10
nm to 2000 nm.
[0022] The substrate is preferably made of a metal or a non-metal
containing silica glass, resin, silicon, gallium nitride, gallium
arsenide, indium phosphor, nickel, iron, titanium, carbon, sapphire
or carbon nitride as a main component.
[0023] The etching layer is preferably composed of one layer made
of an oxide, a nitride or a carbide, or multiple layers made of any
of the oxide, the nitride and the carbide.
[0024] The present invention, for solving the above described
problem, provides a mold for an optical device with an
anti-reflection structure produced by the method of producing the
mold for the optical device.
[0025] The present invention, for solving the above described
problem, provides an optical device comprising a nano pattern
having a nano structure of a fine depressed and elevated surface
formed on a surface of a substrate and arranged at a random.
[0026] It is preferable that the nano pattern of the optical device
with the nano structure is composed of in such a manner as to hold
an interval having a wavelength or less of a light source.
Effect of the Invention
[0027] The following effect occurs according to the present
invention.
[0028] (1) The mold for the optical device according to the present
invention can produce the optical device including the uniformly
stable nano structure to have an anti-reflection effect in a wider
range of wavelengths and including the anti-reflection structure
with little dependency on an incident angle, on the surface of the
optical device with a large area and a complex free curved
surface.
[0029] (2) The method of producing the mold for the optical device
according to the present invention can produce with a fewer steps
and with only dry processes in high productivity.
[0030] (3) The optical device according to the present invention is
an optical device including the nano pattern having the nano
structure of the fine depressed and elevated surface formed on the
surface of the substrate and arranged at a random, preferably this
nano pattern being composed of in such a manner as to hold an
interval having a wavelength or less of a light source.
BRIEF DESCRIPTION OF DRAWINGS
[0031] FIG. 1 is diagrams explaining Example 1 in the present
invention;
[0032] FIG. 2 is diagrams explaining Example 1 in the present
invention;
[0033] FIG. 3 is a diagram explaining Example 1 in the present
invention;
[0034] FIG. 4 is a graph explaining Example 1 in the present
invention;
[0035] FIG. 5 is diagrams explaining Example 2 in the present
invention;
[0036] FIG. 6 is diagrams explaining production of an injection
mold using a mold for an optical device, mold of an optical device,
and an optical device in Example 1 of the present invention;
and
[0037] FIG. 7 is diagrams explaining manufacture of an injection
mold using a mold for an optical device, mold of an optical device,
and an optical device in Example 2 of the present invention.
EXPLANATION OF REFERENCE NUMERALS
[0038] 1: MOLD FOR OPTICAL DEVICE
[0039] 2: SUBSTRATE
[0040] 3: ETCHING TRANSFER LAYER
[0041] 4: THIN FILM FOR PRODUCING ISLAND-LIKE FINE PARTICLE
[0042] 5: ISLAND-LIKE FINE PARTICLE
[0043] 6: MOLD FOR OPTICAL DEVICE
[0044] 7: SUBSTRATE
[0045] 8: INJECTION MOLD
[0046] 9: OPTICAL DEVICE
[0047] 10: INJECTION MOLD
[0048] 11: OPTICAL DEVICE
BEST MODE OF CARRYING OUT THE INVENTION
[0049] The best mode of carrying out a mold for an anti-reflection
device, a method of producing the mold for the optical device and
an optical device according to the present invention will be
explained based on examples with reference to the drawings.
[0050] The present invention relates to a mold for an optical
device for mold an optical device including a fine depressions and
elevations structure (anti-reflection structure) for obtaining an
anti-reflection effect on a surface of the optical device and a
method of producing the mold. The steps in the method of producing
the mold for the optical device according to the present invention
are as follows.
[0051] (1) Steps of Forming a Thin Film on a Substrate
[0052] Plurality of etching transfer layers are formed on the
substrate and a thin film is further formed at a time. These
forming steps are carried out by a vacuum dry process.
[0053] (2) Formation of a Nano Pattern
[0054] Any of heating reaction, photoreaction and gas reaction or
the combined reaction as a combination of two or more of these
reactions is used to cause aggregation, decomposition or nucleation
of the thin film material to form a nano pattern in the thin film
in which a nano-order semispherical island-like fine particles
exist at a random by an interval having a wavelength or less of
light as a target of anti-reflection.
[0055] The material of the island-like fine particle is made of a
material containig any one of silver, gold, platinum and palladium
as a main component, or an oxide material or a nitride containing
any of silver, gold, platinum, palladium, tungsten, bismuth and
tellurium as a main component, and thereby it is possible to form
the nano pattern in which an interval between the plurality of
island-like fine particles is narrow. At this time it is preferable
that the island-like fine particle has an average particle size of
5 nm to 1000 nm and an average interval between the adjacent
island-like fine particles is in a range of 10 nm to 2000 nm.
[0056] (3) By using the nano pattern formed, that is, by using the
island-like fine particles as a protection mask, the etching
transfer layer is etched. Further, the substrate as a target is
finally etched to forma fine conical nano structure on the surface
of the substrate, thus producing a mold for an optical device with
an anti-reflection structure.
[0057] In this case, since the plurality of etching transfer layers
are provided between the island-like material and the substrate as
described above, it is possible to efficiently produce the fine
depressed and elevated surface (anti-reflection structure mold
surface), which can mold the optical device equipped with the
reflection structure of a high aspect ratio, on the surface of mold
for the optical device.
[0058] Use of this mold for the optical device, as explained in the
following examples, enables the optical device including the nano
pattern having the nano structure of the fine depressed and
elevated surface formed on the surface of the substrate and
arranged at a random, preferably this nano pattern being composed
in such a manner as to hold an interval having a wavelength or less
of a light source.
Example 1
[0059] Example 1 of a mold for an optical device according to the
present invention and a method of producing the same will be in
detail explained with reference to the drawings. FIG. 1 is diagrams
explaining the steps of a producing method of producing a mold 1
for an optical device according to Example 1 of the present
invention by using a reactive ion etching method.
[0060] (1) A film forming device (not shown in drawings) is used to
form one or more etching layers 3 and a thin film 4 for producing
island-like fine particles on a surface of a flat substrate 2 (FIG.
1 (a)). The present inventors have confirmed by actual tests that
the material containing silver, gold, platinum or palladium as a
main component is effective as a material of the thin film 4 for
forming island-like fine particles 5 at a random by an interval of
a wavelength or less of light as an anti-reflection target on the
surface of the substrate 2.
[0061] (2) Next, the island-like fine particles 5 are produced
using aggregation, nucleation or decomposition so as to be arranged
at a random by the interval of the wavelength or less (FIG. 1(b)).
FIGS. 2(a) and (b) are a cross section and a plan view each showing
the substrate 2 and island-like fine particles 5 formed on the
etching transfer layer 3.
[0062] Incidentally, a heating reaction, a photoreaction, a gas
reaction or the like become a parameter to control an aggregation
reaction or a nucleation reaction of the material and thereby it is
possible to control an average particle size and an interval of the
island-like fine particles 5. Furthermore, the present inventors
have confirmed that it is possible to control the average particle
size and the interval of the island-like fine particles 5 by adding
impurities to the material of the thin film 4.
[0063] Furthermore, in a case of using an oxide containing anyone
of silver, gold, platinum, palladium, tungsten, bismuth and
tellurium as a main component, it is possible to control the
average particle size and the interval of the island-like fine
particles 5 by using a heating reaction, a photoreaction or gas
decomposition reaction.
[0064] (3) Next, the formed island-like fine particles 5 are used
as a mask to etch the etching transfer layer 3 with a reactive gas
(for example, CF.sub.4, CHF.sub.3, CH.sub.4, CF.sub.6, H.sub.2, CO,
NH.sub.3, Cl.sub.2 or BCl.sub.3) (FIG. 1(c)). Here, the etching
layer 3 is etched to maintain a shape similar to that of the
island-like fine particles 5 and serves sequentially as a masking
layer for the next etching transfer layer 3 or the substrate 2.
[0065] Upon forming a substantially conical fine depressed and
elevated surface (anti-reflection structure mold surface) 1' for
forming an anti-reflection structure of the optical device surface,
on the surface of the substrate 2 using the island-like fine
particles 5, the etching transfer layer 3 is, as described above,
provided, and thereby it is possible to produce the structure
having the substantially conical shape with high aspect ratio. As a
material of the etching transfer layer 3, for example, in a case of
using the island-like fine particle 5 containing silver as a main
component, as a masking layer, a material containing carbon as a
main component, or silicon, silicon oxide or silicon nitride is
effective.
[0066] Here, in a case where the island-like fine particle 5 is
made of silver as a main component, the etching transfer layer 3 is
made of carbon and the substrate 2 is made of silica, the reactive
etching is carried out using the gas and so on in such a manner as
to meet a condition of "an etching speed of the island-like fine
particle 5<<an etching speed of the etching transfer layer
3". In consequence, the island-like fine particle 5 creates a
masking effect, thus making it possible to form a pattern on the
etching transfer layer 3.
[0067] Next, in a case of etching the etching transfer layer 3 and
the substrate 2, the reactive etching is carried out using the gas
and so on in such a manner as to meet a condition of "an etching
speed of the etching transfer layer 3<<an etching speed of
the substrate 2". In consequence, it is possible to produce a
substantially conical anti-reflection structure on the surface of
the substrate using the island-like fine particle 5 as a mask.
Further, the etching transfer layer 3 is not necessarily a single
layer and may be formed in multiple layers depending on the process
design for the etching.
[0068] As to the second and the subsequent etching transfer layers,
the similar process is carried out (FIG. 1(d)) and finally the
substrate 2 is etched, thus forming the mold 1 for the optical
device in which the substantially conical fine depressed and
elevated surface (anti-reflection structure mold surface) 1' is
formed on the surface of the substrate 2 (FIG. 1(f)).
[0069] By using the above producing method, the mold can have the
fine depressed and elevated structure formed in a substantially
conical shape at a random by an interval of a wavelength or less of
light as an anti-reflection target on the surface of the substrate
2 only by the dry process. Thereby, it is possible to easily
produce also an optical lens having a complex shape and
simplification of the producing process can be carried out.
[0070] FIG. 3 shows an SEM image (scanning electronic microscope
image) representative of the island-like fine particles 5 obtained
by carrying out Example 1 by the present inventors. In consequence,
it was confirmed to be capable of forming the island-like fine
particles 5 at a random by an interval of a wavelength or less of
light as an anti-reflection target on the surface of the substrate
2. Furthermore, it was confirmed from this SEM image that as an
effective material of the thin film 4, the material containing
silver as a main component was effective by Example 1.
[0071] Furthermore, the present inventors have confirmed through
the actual testing of Example 1 that the heating reaction, the
photoreaction or the gas reaction is controlled to control the
aggregation reaction or the nucleation reaction of the material and
thereby it is possible to control the average particle size and
then interval of the island-like fine particles 5. Furthermore, the
present inventors have confirmed that it is possible to control the
average particle size and the interval of the island-like fine
particles 5 by adding impurities to the material.
[0072] Furthermore, the present inventors have confirmed that even
in a case where an oxide containing any of gold, platinum,
palladium, tungsten, bismuth, and tellurium as a main component is
used as the thin film forming the island-like fine particles 5, it
is possible to control the average particle size and the interval
of the island-like fine particles 5 by using the heating reaction,
the photoreaction or the gas decomposition reaction.
[0073] FIG. 4 is a graph of reflective characteristics in the mold
1 for the optical device (not the optical device itself) produced
by using the mold 1 for the optical device produced by Example 1.
That is, FIG. 4 is a graph of the reflective characteristics in the
mold 1 for the optical device in which the island-like fine
particles 5 shown in FIG. 3 are used as the masking layer to form
the substantially conical fine depressed and elevated surface
(anti-reflection structure mold surface) 1' on the surface of the
silicon substrate 2 by using the process shown in FIG. 1.
[0074] From this graph, it was confirmed that reflection of about
50% on the plane of the mold 1 for the optical device made of
silicon could be reduced to 5% or less by the mold 1 for the
optical device according to the present invention. From this event,
it was confirmed that the present invention was a method excellent
in low cost and productivity since the substantially conical fine
depressed and elevated surface (anti-reflection structure mold
surface) 1' could be produced on the surface of the substrate 2
only by the dry process.
[0075] Furthermore, it was confirmed that the similar effect was
obtained in a case where silica, glass, resin such as polycarbonate
or PMMA, gallium nitride, gallium arsenide, indium phosphor,
nickel, iron, titanium, carbon, sapphire, carbon nitride or the
like was used as a material of the substrate 2.
Example 2
[0076] FIG. 5 is diagrams explaining the steps carrying out the
method of producing a mold 6 for an optical device according to
Example 2 in the present invention by using the reactive ion
etching method in the same way as in Example 1. Example 2 relates
to a mold for an optical device for molding an optical device
having a free curved surface, and differs in a point that a
substrate 7 has the free curved surface, but since Example 2 has
the same producing method as in Example 1, the explanation is
omitted.
[0077] The mold 6 for the optical device obtained by the producing
method according to Example 2 is provided with a substantially
conical fine depressed and elevated surface (anti-reflection
structure mold surface) 7' formed on a surface of a substrate 7,
and can obtain the same effect as in Example 1 also in regard to
the reflective characteristic.
[0078] (Producing Method of a Mold for Injection Molding and
Molding for an Optical Device)
[0079] Next, using schematic diagrams shown in FIG. 6, a producing
method of a mold for injection molding will be explained from the
mold 1 for the optical device with the anti-reflection structure as
explained above, and one example of a mass production method of the
optical device with the anti-reflection structure by using the mold
for the injection molding will be explained.
[0080] FIG. 6(a) shows the mold 1 for the optical device made of
silicon (mold 1 for the optical device made of silica glass maybe
used) obtained by Example 1 in the present invention. The mold 1
for the optical device made of silicon is, as shown in FIG. 6(b),
used to carry out regular nickel electro-casting treatment, thereby
forming an injection mold 8 as shown in FIG. 6(c).
[0081] Next, using the injection mold 8, as shown in FIG. 6(d), an
optical device 9 as shown in FIG. 6(e) can be mass-produced with
the injection mold 8. This optical device 9 is provided with a nano
pattern having a nano structure of fine depressed and elevated
surface on the surface of the substrate and arranged at a random,
preferably this nano pattern being composed of in such a manner as
to hold an interval of a wavelength or less of a light source.
[0082] Specifically, it is preferable that the nano pattern of the
optical device 9 is island-like and an average particle size
thereof is in a range of 5 nm to 1000 nm and an average interval
between the adjacent islands is in a range of 10 nm to 2000 nm.
[0083] FIG. 7 shows diagrams explaining a method using the mold 6
for the optical device (refer to FIG. 7(a)) obtained by Example 2
in the present invention. This method is exactly the same method as
the method shown in FIG. 6, and the conventional nickel
electro-casting treatment is carried out (refer to FIG. 7(b)),
thereby forming an injection mold 10 (refer to FIG. 7(c)).
[0084] Further, using the injection mold 10, as shown, an optical
device is injection-molded with the injection mold (refer to FIG.
7(d). The optical device 11 also (refer to FIG. 7(e)) can be
mass-produced.
INDUSTRIAL APPLICABILITY
[0085] The present invention, since it is composed of as described
above, can be applied to a general optical device (for example,
lens for a projector, optical pickup, display or the like), a
general light emitting device (for example, LED, laser or the like)
and a general light acceptance device (photo diode, solar cell or
the like).
* * * * *