JP2007066462A - Optical recording and reproducing device and recording and reproducing method of optical recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical recording and reproducing device capable of stably and promptly reproducing information of the same quality as originally recorded information without being affected by the external temperature condition of the optical recording and reproducing device even when a hologram type optical recording medium is used, and the recording and reproducing method of the optical recording medium. <P>SOLUTION: The optical recording and reproducing device comprises: a recording means for irradiating the optical recording medium with information light, reference light and servo light and recording the information in a holographic recording layer; a temperature correction information acquisition means for measuring and recording temperature correction information including at least the recording position of the information in the optical recording medium and a temperature when the information is recorded; and a reproducing means for reading the temperature correction information of a reproducing position before reproducing the information and reproducing the information recorded in the holographic recording layer by irradiating the optical recording medium with the reference light and the servo light at the temperature adjusted such that a difference between the temperature of the optical recording medium during reproduction and the temperature of the optical recording medium during recording is in the range of -2 to 2°C on the basis of the temperature correction information. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  Even when a hologram type optical recording medium is used, the present invention can stably and quickly reproduce information of the same quality as originally recorded information regardless of the external temperature condition of the optical recording / reproducing apparatus. The present invention relates to an optical recording / reproducing apparatus and an optical recording medium recording / reproducing method.

  An optical recording medium is one of recording media capable of writing a large amount of information such as high-density image data. As this optical recording medium, for example, a rewritable optical recording medium such as a magneto-optical disk and a phase change optical disk and a write-once optical recording medium such as a CD-R have already been put into practical use. The demand for larger capacity is increasing. However, all conventionally proposed optical recording media are two-dimensional recording, and there is a limit to increasing the recording capacity. Therefore, recently, a hologram type optical recording medium capable of recording information three-dimensionally has attracted attention.

In the hologram type optical recording method, in general, information light given a two-dimensional intensity distribution and reference light having a substantially constant intensity are superposed inside a photosensitive recording layer to form them. Information is recorded by generating a distribution of optical characteristics inside the recording layer using interference fringes. On the other hand, in reading (reproducing) written information, the recording layer is irradiated with only the reference light in the same arrangement as in recording, and the reproducing light having an intensity distribution corresponding to the optical characteristic distribution formed inside the recording layer is used. This is done by emitting from the recording layer.
In this hologram type optical recording method, since the optical characteristic distribution is three-dimensionally formed in the recording layer, an area where information is written by one information light, an area where information is written by other information light, and Can be partially overlapped, that is, multiple recording is possible. When digital volume holography is used, the signal-to-noise ratio (S / N ratio) of one spot is extremely high, so that the original information can be faithfully reproduced even if the S / N ratio is somewhat lowered by overwriting. . As a result, the number of times of multiple recording reaches several hundreds, and the recording capacity of the optical recording medium can be remarkably increased (see Patent Document 1).

  In this way, volume holographic recording differs from the conventional method of recording information in the form of pits (marks), because interference fringes are written in the form of a refractive index image in a certain volume, so the volume shrinkage of the recording layer material due to external temperature In addition, the shape of the refractive index image easily changes due to volume expansion, and there is a problem that a signal to be reproduced cannot be reproduced correctly.

  Therefore, in order to stably reproduce information of the same quality as originally recorded information, it is desired to reproduce at the same temperature as that at the time of recording. For example, an optical recording medium recording / reproducing method and an optical recording / reproducing apparatus capable of separately recording temperature information during recording and reflecting the recording temperature information during reproduction are necessary. In order to generalize the reproduction method and the optical recording / reproducing apparatus, it is desired to perform a certain controlled recording / reproducing process. It is.

JP 2002-123949 A

  An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention reproduces information of the same quality as the originally recorded information stably and promptly regardless of the external temperature condition of the optical recording / reproducing apparatus, even when using a hologram type optical recording medium. It is an object of the present invention to provide an optical recording / reproducing apparatus and a method for recording / reproducing an optical recording medium.

Means for solving the problems are as follows. That is,
<1> Recording means for recording information on the holographic recording layer by irradiating the optical recording medium with information light, reference light, and servo light;
Temperature correction information acquisition means for measuring and recording temperature correction information including at least a recording position of information on the optical recording medium and a temperature at the time of information recording at the time of recording information;
The temperature correction information at the reproduction position is read before reproducing the information, and the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is based on the temperature correction information is in the range of −2 to + 2 ° C. And reproducing means for reproducing the information recorded in the holographic recording layer by irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be It is.
<2> The optical recording / reproducing apparatus according to <1>, wherein the temperature correction information acquisition unit includes a non-contact type thermometer that measures a temperature at the time of recording information.
<3> The optical recording / reproducing apparatus according to <2>, wherein the non-contact thermometer is an infrared laser non-contact thermometer.
<4> The optical recording / reproducing apparatus according to any one of <1> to <3>, wherein the temperature correction information is recorded on the same optical recording medium as the information recording medium.
<5> The optical recording / reproducing apparatus according to <4>, wherein the optical recording medium includes a volume holographic recording area and a pit pattern recording area independently of each other.
<6> The temperature correction information recorded in the pit pattern recording area is at least a recording position in the optical recording medium of information recorded in the volume holographic recording area and a temperature at the time of recording the information. An optical recording / reproducing apparatus.
<7> The information light and the reference light are irradiated on the optical recording medium so that the optical axis of the information light and the optical axis of the reference light are coaxial, and the interference between the information light and the reference light The optical recording / reproducing apparatus according to any one of <1> to <6>, wherein information is recorded on the holographic recording layer by a generated interference pattern.
<8> A recording step of recording information on the holographic recording layer by irradiating the optical recording medium with information light and reference light, and servo light;
A temperature correction information acquisition step of measuring and recording temperature correction information including at least a recording position of information in the optical recording medium and a temperature at the time of recording information at the time of recording information;
The temperature correction information at the reproduction position is read before reproducing the information, and the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is based on the temperature correction information is in the range of −2 to + 2 ° C. A reproducing step of reproducing information recorded on the holographic recording layer by irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be This is a recording / reproducing method.
<9> Irradiation of the information light and the reference light to the optical recording medium is performed so that the optical axis of the information light and the optical axis of the reference light are coaxial, and the information light and the reference light are The recording / reproducing method for an optical recording medium according to <8>, wherein information is recorded on the holographic recording layer by an interference pattern generated by interference.

The optical recording / reproducing apparatus of the present invention comprises a recording means for recording information on a holographic recording layer by irradiating an optical recording medium with information light, reference light, and servo light,
Temperature correction information acquisition means for measuring and recording temperature correction information including at least a recording position of information on the optical recording medium and a temperature at the time of recording information when recording information;
The temperature correction information at the reproduction position is read before reproducing the information, and the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is based on the temperature correction information is in the range of −2 to + 2 ° C. And reproducing means for reproducing the information recorded in the holographic recording layer by irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be
The optical recording / reproducing apparatus of the present invention has temperature correction information acquisition means that can accurately grasp temperature information at the time of recording information on the optical recording medium, and can be adjusted to an appropriate temperature condition at the time of information reproduction. Even when a hologram type optical recording medium is used, information having the same quality as the originally recorded information can be reproduced stably and promptly regardless of the external temperature condition of the optical recording / reproducing apparatus.

The recording / reproducing method of the optical recording medium of the present invention includes a recording step of recording information on the holographic recording layer by irradiating the optical recording medium with information light, reference light, and servo light,
A temperature correction information acquisition step of measuring and recording temperature correction information including at least a recording position of information in the optical recording medium and a temperature at the time of recording information at the time of recording information;
The temperature correction information at the reproduction position is read before reproducing the information, and the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is based on the temperature correction information is in the range of −2 to + 2 ° C. A reproducing step of reproducing the information recorded on the holographic recording layer by irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be
The optical recording medium recording / reproducing method of the present invention includes a temperature correction information acquisition step capable of accurately grasping temperature information at the time of recording information, and can be adjusted to an appropriate temperature condition at the time of information reproduction. Even when a type optical recording medium is used, information of the same quality as originally recorded information can be reproduced stably and promptly without being influenced by the external temperature condition of the optical recording / reproducing apparatus.

  According to the present invention, various problems in the prior art can be solved, and even when a hologram type optical recording medium is used, the same quality information as originally recorded information can be obtained regardless of the external temperature condition of the optical recording / reproducing apparatus. It is possible to provide an optical recording / reproducing apparatus and an optical recording medium recording / reproducing method capable of reproducing stably and quickly.

(Optical recording / reproducing apparatus and optical recording medium recording / reproducing method)
The optical recording / reproducing apparatus of the present invention comprises recording means, temperature correction information acquisition means, and reproducing means, and further comprises other means as necessary.
The optical recording medium recording / reproducing method of the present invention includes a recording step, a temperature correction information acquisition step, and a reproducing step, and further includes other steps as necessary.
The optical recording medium recording / reproducing method of the present invention can be preferably implemented by the optical recording / reproducing apparatus of the present invention, the recording step can be performed by the recording means, and the temperature correction information obtaining step can be performed by the temperature. It can be performed by correction information acquisition means, the reproduction step can be performed by the reproduction means, and the other steps can be performed by the other means.

<Recording means and recording process>
The recording step is a step of recording information on the holographic recording layer by irradiating the optical recording medium with information light, reference light, and servo light, and is performed by the recording means.

The information light and the reference light are not particularly limited and can be appropriately selected according to the purpose. For example, a coherent laser beam emitted from a light source is preferable.
There is no restriction | limiting in particular as said laser beam, According to the objective, it can select suitably, For example, the laser beam etc. which consist of 1 or more types of wavelengths selected from 360-850 nm are mentioned. The wavelength is preferably 380 to 800 nm, more preferably 400 to 750, and most preferably 500 to 600 nm.
When the wavelength is less than 360 nm, a clear three-dimensional image may not be obtained. When the wavelength is greater than 850 nm, the interference fringes may become fine, and a corresponding photosensitive material may not be obtained.
There is no restriction | limiting in particular as said servo light, According to the objective, it can select suitably, For example, the wavelength is 600-900 nm light.

  The light source of the laser light is not particularly limited and may be appropriately selected according to the purpose. For example, a solid-state laser light oscillator, a semiconductor laser light oscillator in a blue region, a liquid laser light oscillator, a gas laser light such as argon Examples thereof include an oscillator, a He—Cd laser oscillator, a frequency doubled YAG laser oscillator, a He—Ne laser oscillator, and a Kr laser oscillator. Of these, a gas laser light oscillator, a semiconductor laser light oscillator in the blue region, and the like are preferable.

The irradiation method of the information light and the reference light is not particularly limited and can be appropriately selected according to the purpose. For example, the information light is divided by dividing one laser light emitted from the same light source. Further, it may be irradiated as reference light, or may be irradiated with two laser beams emitted from different light sources.
There is no restriction | limiting in particular as an irradiation direction of the said information light and the said reference light, According to the objective, it can select suitably, For example, the said information light and the said reference light may be irradiated from a different direction, and are the same It may be irradiated in the direction. Further, it may be irradiated such that the optical axis of the information light and the optical axis of the reference light are coaxial.

<Temperature correction information acquisition step and temperature correction information acquisition means>
The temperature correction information acquisition step is a step of measuring and recording temperature information including at least a recording position of the information on the optical recording medium and a temperature at the time of recording the information at the time of recording the information. Done.

  The temperature correction information acquisition means is not particularly limited and can be appropriately selected depending on the purpose.However, from the viewpoint of vibration control, surface blur prevention, surface protection, and accuracy of the optical recording medium, It is preferable to include a non-contact type thermometer that measures the temperature during recording. There is no restriction | limiting in particular as this non-contact-type thermometer, Although it can select suitably according to the objective, For example, an infrared laser non-contact-type thermometer etc. are mentioned.

  The information recorded by the temperature correction information acquisition means includes at least the recording position of the recorded information on the optical recording medium and the temperature at the time of recording, and further, the type of optical recording medium, date and time information, index, etc. Is mentioned.

  The measured recording position and temperature information may be recorded on the same optical recording medium as the information recording medium, or temporarily stored in the optical recording / reproducing apparatus and then stored on another recording medium. It may be recorded, or may be stored in the optical recording / reproducing apparatus together with the identification information of the optical recording medium. Among these, it is particularly preferable to record on the same optical recording medium as the optical recording medium on which information is recorded, because the optical recording medium can be reproduced by an unspecified number of optical recording / reproducing apparatuses. .

The optical recording medium that can be recorded on the same optical recording medium as the information recording medium is not particularly limited and may be appropriately selected according to the purpose. For example, volume holographic recording What has an area | region and a pit pattern recording area | region is suitable.
In this way, the information on the recording position of the information recorded in the volume holographic recording area in the optical recording medium and the temperature information at the time of recording can be recorded in the pit pattern recording area where the writing of information is not affected by the temperature condition. When reproducing the information recorded in the volume holographic recording area, reading the temperature information described in the pit pattern recording area and controlling the temperature at the time of reproduction enables accurate and stable reproduction It becomes.

The volume holographic recording area and the pit pattern recording area are preferably independent areas.
Here, the “independent area” means that the volume holographic recording area and the pit pattern recording area do not have overlapping portions. If there is an overlapped portion, a small amount of heat is generated when information is read from the pit pattern recording area, and temperature management that should be controlled may not be performed properly.
The arrangement of the volume holographic recording area and the pit pattern recording area is not particularly limited and may be appropriately selected according to the purpose. For example, as shown in FIG. 2 has a volume holographic recording area 201 and a pit pattern recording area 202 on the inner periphery, and as shown in FIG. 2, an arc-shaped volume holographic recording area 201 and an arc-shaped pit pattern recording area. 202, and the like. In FIGS. 1 and 2, reference numeral 203 denotes a chucking hole. Among these, the embodiment shown in FIG. 1 is preferable from the viewpoint of production suitability.

The area ratio of the area of the volume holographic recording area to the total recording area of the optical recording medium is preferably 10 to 95%, more preferably 20 to 90%, still more preferably 30 to 80%. If the area ratio exceeds 95%, the area of the pit pattern recording area becomes too small, and temperature information for every piece of information recorded in the volume holographic recording area cannot be recorded in the pit pattern recording area. In some cases, if it is less than 10%, the area of the volume holographic recording area becomes too small, and the recording capacity as a large-capacity optical recording medium may not be ensured.
The area ratio of the area of the pit pattern recording area to the total recording area of the optical recording medium is preferably 5 to 90%, more preferably 10 to 80%, and still more preferably 20 to 70%. If the area ratio is less than 5%, the area of the pit pattern recording area becomes too small, and temperature information for every piece of information recorded in the volume holographic recording area can be recorded in the pit pattern recording area. If it exceeds 90%, the area of the volume holographic recording area may become too small, and the recording capacity as a large-capacity optical recording medium may not be ensured.

[Volume holographic recording area]
The volume holographic recording region includes at least a first substrate, a selective reflection layer, a holographic recording layer, and a second substrate, and further includes other layers as necessary. .

-Holographic recording layer-
The holographic recording layer is not particularly limited as long as it can be recorded and reproduced using the principle of hologram, and records a large amount of information such as a relatively thin planar hologram or a three-dimensional image for recording information such as two dimensions. The volume hologram may be either a transmission type or a reflection type. The hologram recording method may be any, for example, an amplitude hologram, a phase hologram, a blazed hologram, a complex amplitude hologram, or the like.
Among these, information recording in the volume holographic recording area is performed by irradiating the volume holographic recording area with information light and reference light as a coaxial light beam, and recording information by an interference pattern due to interference between the information light and the reference light. The so-called collinear method is particularly preferable.

  The material of the recording layer is not particularly limited and may be appropriately selected depending on the purpose. For example, (1) a photopolymer that undergoes polymerization reaction upon irradiation with light and becomes a polymer, (2) a photorefractive effect ( (3) Photochromic material in which molecular isomerization occurs due to light irradiation and the refractive index is modulated, (4) Lithium niobate, titanic acid Examples thereof include inorganic materials such as barium, and (5) chalcogen materials.

  The photopolymer (1) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the photopolymer contains a monomer and a photoinitiator, and further a sensitizer or oligomer as necessary. It contains other components such as.

  Examples of the photopolymer include “Photopolymer Handbook” (Industry Research Society, 1989), “Photopolymer Technology” (Nikkan Kogyo Shimbun, 1989), SPIE Proceedings Vol. 3010 p354-372 (1997), and SPIE Proceedings Vol. 3291 p89-103 (1998) can be used. Also, US Pat. Nos. 5,759,721, 4,942,112, 4,959,284, 6,221,536, International Publication No. No. 97/44714, No. 97/13183, No. 99/26112, No. 97/13183, No. 2880342, No. 2873126, No. 2849021, No. Photopolymers described in Japanese Patent Nos. 3070882, 3161230, Japanese Patent Application Laid-Open No. 2001-316416, Japanese Patent Application Laid-Open No. 2000-275859, and the like can be used.

  Examples of a method for changing the optical characteristics by irradiating the photopolymer with recording light include a method using diffusion of a low molecular component. Moreover, in order to relieve the volume change at the time of superposition | polymerization, the component which diffuses in the reverse direction to a superposition | polymerization component may be added, or the compound which has an acid cleavage structure may be added separately besides a polymer. In the case where the recording layer is formed using the photopolymer containing the low molecular component, a structure capable of holding the liquid in the recording layer may be required. Moreover, when adding the compound which has the said acid cleavage structure, you may suppress a volume change by compensating the expansion | swelling which arises by the cleavage, and the shrinkage which arises by superposition | polymerization of a monomer.

  The monomer is not particularly limited and may be appropriately selected depending on the purpose. For example, a radical polymerization type monomer having an unsaturated bond such as an acryl group or a methacryl group, an epoxy ring or an oxetane ring. Examples thereof include a cationic polymerization type monomer having an ether structure. These monomers may be monofunctional or polyfunctional. Moreover, you may utilize a photocrosslinking reaction.

Examples of the radical polymerization type monomer include acryloylmorpholine, phenoxyethyl acrylate, isobornyl acrylate, 2-hydroxypropyl acrylate, 2-ethylhexyl acrylate, 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, neo Pentyl glycol PO-modified diacrylate, 1,9-nonanediol diacrylate, hydroxypivalate neopentyl glycol diacrylate, EO-modified bisphenol A diacrylate, polyethylene glycol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol hexa Acrylate, EO-modified glycerol triacrylate, trimethylol pro Triacrylate, EO-modified trimethylolpropane triacrylate, 2-naphth-1-oxyethyl acrylate, 2-carbazoyl-9-ylethyl acrylate, (trimethylsilyloxy) dimethylsilylpropyl acrylate, vinyl-1-naphthoate, N-vinylcarbazole , Etc.
Examples of the cationic polymerization type monomer include bisphenol A epoxy resin, phenol novolac epoxy resin, glycerol triglycidyl ether, 1,6-hexane glycidyl ether, vinyltrimethoxysilane, 4-vinylphenyltrimethoxysilane, and γ-methacrylic acid. Examples include loxypropyltriethoxysilane and compounds represented by the following structural formulas (A) to (E).
These monomers may be used alone or in combination of two or more.

The photoinitiator is not particularly limited as long as it has sensitivity to recording light, and examples thereof include materials that cause radical polymerization, cationic polymerization, crosslinking reaction, and the like by light irradiation.
Examples of the photoinitiator include 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,1′-biimidazole, 2,4,6-tris ( Trichloromethyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (p-methoxyphenylvinyl) -1,3,5-triazine, diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluoro Phosphate, 4,4'-di-t-butyldiphenyliodonium tetrafluoroborate, 4-diethylaminophenylbenzenediazonium hexafluorophosphate, benzoin, 2-hydroxy-2-methyl-1-phenylpropan-2-one, benzophenone, thioxanthone 2,4,6-trimethylbenzoyldiphenyla Examples thereof include silphosphine oxide, triphenylbutyl borate tetraethylammonium, and a titanocene compound represented by the following structural formula. These may be used individually by 1 type and may use 2 or more types together. Moreover, you may use a sensitizing dye together according to the wavelength of the light to irradiate.

  The photopolymer can be obtained by stirring and mixing the monomer, the photoinitiator, and, if necessary, other components and reacting them. If the obtained photopolymer has a sufficiently low viscosity, a recording layer can be formed by casting. On the other hand, in the case of a high-viscosity photopolymer that cannot be cast, the photopolymer is placed on the lower substrate using a dispenser, and pressed onto the photopolymer so as to cover the upper substrate, and the recording layer is spread over the entire surface. Can be formed.

  The photorefractive material (2) is not particularly limited as long as it exhibits a photorefractive effect, and can be appropriately selected according to the purpose. For example, it contains a charge generation material and a charge transport material. And further contains other components as necessary.

The charge generation material is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include phthalocyanine dyes / pigments such as metal phthalocyanine, metal-free phthalocyanine, or derivatives thereof; naphthalocyanine dye / pigment; monoazo Azo dyes / pigments such as diazo and trisazo; perylene dyes / pigments; indigo dyes / pigments; quinacridone dyes / pigments; polycyclic quinone dyes / pigments such as anthraquinone and anthanthrone; cyanine dyes / pigments; Examples include a charge transfer complex composed of an electron accepting substance and an electron donating substance represented by TTF-TCNQ; an azurenium salt; a fullerene represented by C ₆₀ and C ₇₀ and a methanofullerene which is a derivative thereof. . These may be used individually by 1 type and may use 2 or more types together.

The charge transport material is a material that transports holes or electrons, and may be a low molecular compound or a high molecular compound.
The charge transport material is not particularly limited and may be appropriately selected depending on the intended purpose. For example, indole, carbazole, oxazole, inoxazole, thiazole, imidazole, pyrazole, oxadiazole, pyrazoline, thiathiazole, triazole Nitrogen-containing cyclic compounds such as, or derivatives thereof; hydrazone compounds; triphenylamines; triphenylmethanes; butadienes; stilbenes; quinone compounds such as anthraquinone diphenoquinone, or derivatives thereof; C ₆₀ and C _70, etc. Fullerenes and derivatives thereof; π-conjugated polymers or oligomers such as polyacetylene, polypyrrole, polythiophene, and polyaniline; σ-conjugated polymers or oligomers such as polysilane and polygermane; anthracene, pyrene, phenanthrene, Polycyclic aromatic compounds such Ronen, and the like. These may be used individually by 1 type and may use 2 or more types together.

  As a method for forming a recording layer using the photorefractive material, for example, a coating film is formed using a coating solution obtained by dissolving or dispersing the photorefractive material in a solvent, and the solvent is removed from the coating film. By doing so, a recording layer can be formed. Alternatively, the recording layer can be formed by forming a coating film using the photorefractive material that has been heated and fluidized and rapidly cooling the coating film.

  The photochromic material (3) is not particularly limited as long as it is a material that causes a photochromic reaction, and can be appropriately selected according to the purpose. For example, an azobenzene compound, a stilbene compound, an indigo compound, a thioindigo compound, a spiropyran compound, Examples include spirooxazine compounds, fluoride compounds, anthracene compounds, hydrazone compounds, and cinnamic acid compounds. Among these, azobenzene derivatives and stilbene derivatives that cause a structural change by cis-trans isomerization by light irradiation, spiropyran derivatives and spirooxazine derivatives that cause a ring-opening and ring-closing structural change by light irradiation are particularly preferable.

Examples of the chalcogen material of (5) include, for example, a material containing a chalcogenide glass containing a chalcogen element and metal particles made of a metal that is dispersed in the chalcogenide glass and can be diffused in the chalcogenide glass by light irradiation, Etc.
The chalcogenide glass is composed of a non-oxide type amorphous material containing a chalcogen element of S, Te, or Se, and is not particularly limited as long as it can dope metal particles.
Examples of the amorphous material containing the chalcogen element include Ge—S glass, As—S glass, As—Se glass, As—Se—Ce glass, and the like. S-based glass is preferred. When Ge—S glass is used as the chalcogenide glass, the composition ratio of Ge and S constituting the glass can be arbitrarily changed according to the wavelength of light to be irradiated, but is mainly represented by GeS _2. A chalcogenide glass having a chemical composition is preferred.
The metal particles are not particularly limited as long as they have the property of being light-doped into chalcogenide glass by light irradiation, and can be appropriately selected according to the purpose. For example, Al, Au, Cu, Cr, Ni, Pt, Sn, In, Pd, Ti, Fe, Ta, W, Zn, Ag, etc. are mentioned. Among these, Ag, Au, or Cu has a characteristic that it is more likely to cause light doping, and Ag is particularly preferable because it significantly causes light doping.
The content of the metal particles dispersed in the chalcogenide glass is preferably 0.1 to 2% by volume, more preferably 0.1 to 1.0% by volume based on the total volume of the recording layer. If the content of the metal particles is less than 0.1% by volume, the change in transmittance due to light doping may be insufficient, and the recording accuracy may decrease. The transmittance may be lowered, and it may be difficult to sufficiently generate light dope.

  The recording layer can be formed according to a known method depending on the material. For example, a vapor deposition method, a wet film formation method, an MBE (molecular beam epitaxy) method, a cluster ion beam method, a molecular lamination method, an LB method, It can be suitably formed by a printing method, a transfer method, or the like. Among these, a vapor deposition method and a wet film-forming method are preferable.

  There is no restriction | limiting in particular as said vapor deposition method, Although it can select suitably from well-known things according to the objective, For example, a vacuum evaporation method, resistance heating vapor deposition, chemical vapor deposition method, physical vapor deposition method etc. are mentioned. . Examples of the chemical vapor deposition method include a plasma CVD method, a laser CVD method, a thermal CVD method, and a gas source CVD method.

  Formation of the recording layer by the wet film formation method can be suitably performed by using (coating and drying) a solution (coating liquid) in which the recording layer material is dissolved or dispersed in a solvent. The wet film forming method is not particularly limited and can be appropriately selected from known ones according to the purpose. For example, an ink jet method, a spin coating method, a kneader coating method, a bar coating method, a blade coating method, Examples thereof include a casting method, a dip method, and a curtain coating method.

  There is no restriction | limiting in particular as thickness of the said recording layer, According to the objective, it can select suitably, 150-1,000 micrometers is preferable, 200-750 micrometers is more preferable, 300-600 micrometers is still more preferable. Within this range, it is possible to perform good volume holographic optical information recording with high manufacturability. If the thickness exceeds 1,000 μm, it may be difficult in terms of cost and manufacturing method, and if it is less than 150 μm, it may not be possible to achieve both signal strength and multiplexing performance.

-Board-
The shape, structure, size and the like of the substrate are not particularly limited and can be appropriately selected according to the purpose. Examples of the shape include a disk shape, a card shape, a plate shape, and a sheet shape. The structure may be a single layer structure or a laminated structure, and the size may be appropriately selected according to the size of the optical recording medium. .

The material of the substrate is not particularly limited, and any of inorganic materials and organic materials can be preferably used. However, the mechanical strength of the optical recording medium can be ensured, and light used for recording and reproduction can be obtained. In the case of a transmissive type incident through a substrate, it is necessary to be sufficiently transparent in the wavelength region of light used.
Examples of the inorganic material include glass, quartz, silicon, and the like.
Examples of the organic material include acetate resins such as triacetyl cellulose, polyester resins, polyethersulfone resins, polysulfone resins, polycarbonate resins, polyamide resins, polyimide resins, polyolefin resins, and acrylic resins. Polynorbornene resin, cellulose resin, polyarylate resin, polystyrene resin, polyvinyl alcohol resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyacrylic resin, polylactic acid resin, plastic film laminated paper And synthetic paper. These may be used individually by 1 type and may use 2 or more types together. Among these, polycarbonate resins and acrylic resins are preferable from the viewpoints of moldability, optical characteristics, and cost.

As said board | substrate, what was synthesize | combined suitably may be used and a commercial item may be used.
There is no restriction | limiting in particular as thickness of the said board | substrate, According to the objective, it can select suitably, 0.1-5 mm is preferable and 0.3-2 mm is more preferable. If the thickness of the substrate is less than 0.1 mm, distortion of the shape during storage of the disk may not be suppressed. If the thickness exceeds 5 mm, the weight of the entire disk increases and is rotated by a drive motor or the like. In some cases, an excessive load may be applied.

  The substrate is provided with a plurality of address-servo areas serving as positioning areas extending linearly in the radial direction at predetermined angular intervals, and a sector-shaped section between adjacent address-servo areas is a data area. In the address-servo area, information for performing focus servo and tracking servo by the sampled servo method and address information are recorded in advance by embossed pits (servo pits) (preformat). Note that the focus servo can be performed using the reflective surface of the reflective film. As information for performing the tracking servo, for example, a wobble pit can be used.

-Reflective film-
The reflective film is formed on the surface of the servo pit pattern of the substrate.
As the material of the reflective film, a material having a high reflectance with respect to recording light or reference light is preferably used. When the wavelength of light to be used is 400 to 780 nm, for example, Al, Al alloy, Ag, Ag alloy, etc. are preferably used. When the wavelength of light to be used is 650 nm or more, it is preferable to use Al, Al alloy, Ag, Ag alloy, Au, Cu alloy, TiN, or the like.
As the reflective film, an optical recording medium that reflects light and can be written or erased, such as a DVD (digital video disk), is used. It is also possible to add and rewrite directory information such as information on which part has an error and how replacement processing is performed without affecting the hologram.

The formation of the reflective film is not particularly limited and can be appropriately selected according to the purpose. Various vapor deposition methods such as vacuum deposition, sputtering, plasma CVD, photo CVD, ion plating An electron beam evaporation method or the like is used. Among these, the sputtering method is excellent in terms of mass productivity and film quality.
The thickness of the reflective film is preferably 50 nm or more, and more preferably 100 nm or more so that sufficient reflectance can be realized.

-Selective reflection layer-
The selective reflection layer is provided on a servo pit of the substrate or on the reflection layer.
The selective reflection layer has a wavelength selective reflection function of reflecting only light of a specific wavelength from among a plurality of types of light rays. In particular, the selective reflection wavelength does not shift even when the incident angle changes, and the function of preventing irregular reflection from the reflection film of the optical recording medium by the information light and the reference light, and also preventing the occurrence of noise. By laminating the selective reflection layer on the recording medium, optical recording with high resolution and excellent diffraction efficiency can be obtained.
There is no restriction | limiting in particular as said selective reflection layer, According to the objective, it can select suitably, For example, a dichroic mirror layer, a color material containing layer, a dielectric material vapor deposition layer, a single layer or two or more cholesteric layers, and required It is formed by a laminate in which at least one of other layers appropriately selected according to the above is laminated.
The selective reflection layer may be laminated together with the direct recording layer on the substrate by coating or the like. The selective reflection layer is laminated on a substrate such as a film to produce a selective reflection layer, which is laminated on the substrate. It doesn't matter.

  There is no restriction | limiting in particular as said other layer, According to the objective, it can select suitably, For example, a 1st gap layer, a 2nd gap layer, etc. are mentioned.

The first gap layer is provided between the selective reflection layer and the reflection film as necessary, and is formed for the purpose of smoothing the second substrate surface. It is also effective for adjusting the size of the hologram generated in the recording layer. That is, since the recording layer needs to form an interference region of the reference light and the information light to a certain size, it is effective to provide a gap between the recording layer and the servo pit pattern.
The first gap layer can be formed, for example, by applying a material such as an ultraviolet curable resin on the servo pit pattern by spin coating or the like and curing it. Moreover, when using what apply | coated and formed on the transparent base material as a filter layer, this transparent base material will work | function also as a 1st gap layer.
There is no restriction | limiting in particular as thickness of said 1st gap layer, According to the objective, it can select suitably, 1-100 micrometers is preferable.

The second gap layer is provided between the recording layer or the photodegradable recording layer and the selective reflection layer as necessary. In the second gap layer, if the portion of the point where the information light and the reference light are focused is filled with a photopolymer, excessive exposure of the monomer occurs when the overexposure is performed, and the multiple recording capability may be reduced. There is a function to prevent this harmful effect.
There is no restriction | limiting in particular as a material of said 2nd gap layer, According to the objective, it can select suitably, For example, a triacetyl cellulose (TAC), a polycarbonate (PC), a polyethylene terephthalate (PET), polystyrene (PS) ), Transparent resin films such as polysulfone (PSF), polyvinyl alcohol (PVA), polymethyl methacrylate = polymethyl methacrylate (PMMA), etc., or JSR brand name ARTON film or Nippon Zeon brand name ZEONOR And norbornene-based resin films. Among these, those having high isotropic properties are preferred, and TAC, PC, trade name ARTON, and trade name ZEONOR are particularly preferred.
There is no restriction | limiting in particular as thickness of said 2nd gap layer, According to the objective, it can select suitably, 1-200 micrometers is preferable.

[Pit pattern recording area]
The pit pattern recording area includes at least a first substrate, a pit pattern recording layer, and a second substrate in this order, and further includes other layers as necessary.
For recording and reproducing information in the pit pattern recording area, the same system such as DVD and CD can be adopted, but the DVD system is preferable from the viewpoint of recording capacity.
As the first and second substrates, the same one as the volume holographic recording area is used.

-Dye-containing recording layer-
The pit pattern recording layer is preferably a dye-containing recording layer.
The dye-containing recording layer is a layer that causes some optical change upon irradiation with laser light and records information by the change, and a material containing an organic dye as a main component is used. Here, the main component means that it contains a sufficient amount of an organic dye necessary for recording and reproduction, but usually only an organic dye is used except for a small amount of additives that are appropriately added as necessary. Is preferred.
Examples of the organic dye include azo dyes, formazan dyes, dipyrromethene dyes, (poly) methine dyes, naphthalocyanine dyes, phthalocyanine dyes, tetraazaporphyrin dyes, squarylium dyes, croconium dyes, Pyrylium dyes, naphthoquinone dyes, anthraquinone dyes (indanthrene dyes), xanthene dyes, triphenylmethane dyes, azulene dyes, tetrahydrocholine dyes, phenanthrene dyes, triphenothiazine dyes, or their metals Examples include complexes. One of these may be used alone, or two or more may be combined.
Among these, azo (metal chelate) dye, formazan (metal chelate) dye, squarylium (metal chelate) dye, dipyrromethene (metal chelate) dye, trimethine cyanine dye, and tetraazaporphyrin dye are particularly preferable.

A metal or a metal compound may be added to the dye. As the metal or metal compound, for example, In, Te, Bi, Se, Sb, Ge, Sn, Al, Be, TeO ₂ , SnO, As, Cd and the like can be dispersedly mixed or used in a laminated form. .
In addition, a polymer material can be blended in the dye. As the polymer material, for example, various materials such as ionomer resin, polyamide resin, vinyl resin, natural polymer compound, silicone, liquid rubber, or silane coupling agent may be dispersed and mixed. Alternatively, stabilizers (for example, transition metal complexes), dispersants, flame retardants, lubricants, antistatic agents, surfactants, plasticizers, and the like can be used together for the purpose of improving characteristics.

  The dye-containing recording layer can be formed by ordinary means such as a vapor deposition method, a sputtering method, a CVD method, or a solution coating method. When the coating method is used, it can be performed by a conventional coating method such as a spray method, a roller coating method, a dipping method, or a spin coating by dissolving the dye or the like in an organic solvent or the like.

The organic solvent is not particularly limited and may be appropriately selected depending on the intended purpose. For example, alcohols such as methanol, ethanol, isopropanol, 2,2,3,3-tetrafluoropropanol; acetone, methyl ethyl ketone, Ketones such as cyclohexanone; amides such as N, N-dimethylformamide and N, N-dimethylacetamide; sulfoxides such as dimethyl sulfoxide; ethers such as tetrahydrofuran, dioxane, diethyl ether and ethylene glycol monomethyl ether; methyl acetate; Esters such as ethyl acetate; Aliphatic halogenated hydrocarbons such as chloroform, methylene chloride, dichloroethane, carbon tetrachloride, and trichloroethane; Aromatics such as benzene, xylene, monochlorobenzene, and dichlorobenzene ; Methoxyethanol, cellosolves such as ethoxyethanol; hexane, pentane, cyclohexane, hydrocarbons such as methylcyclohexane, and the like.
The thickness of the dye-containing recording layer is not particularly limited and may be appropriately selected depending on the purpose. It is usually preferably 100 mm (10 nm) to 10 μm.

In the pit pattern recording area, a protective layer, an intermediate layer, and the like can be provided as necessary.
The protective layer and the intermediate layer are intended to (1) protect the dye-containing recording layer from scratches, dust, dirt, etc., (2) improve the storage stability of the dye-containing recording layer, and (3) improve the reflectance. Used as. As the material for the protective layer and the intermediate layer, an inorganic material or an organic material is used. As the inorganic material, for example, SiO, SiO ₂ or the like can be used. Examples of the organic material include polymethyl acrylate resin, polycarbonate resin, epoxy resin, polystyrene resin, polyester resin, vinyl resin, cellulose, aliphatic hydrocarbon resin, aromatic hydrocarbon resin, natural rubber, styrene-butadiene resin, Thermosoftening resins such as chloroprene rubber, wax, alkyd resin, drying oil, rosin, heat melting resin, UV curable resin and the like can also be used. Among these, an ultraviolet curable resin excellent in productivity is particularly preferable.
As in the case of the dye-containing recording layer, the protective layer and the intermediate layer may further include a stabilizer, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer, and the like depending on the purpose. Can be contained.
There is no restriction | limiting in particular in the thickness of the said protective layer and intermediate | middle layer, According to the objective, it can select suitably, 0.01-30 micrometers is preferable and 0.05-10 micrometers is more preferable.

Here, the optical recording medium of the present invention will be described in more detail with reference to the drawings.
FIG. 3 is a schematic sectional view showing an example of the configuration of the volume holographic recording area of the optical recording medium of the present invention.
In this optical recording medium 21, a servo pit pattern 3 is formed on a first substrate 1 made of polycarbonate resin, and a reflective film 2 is provided on the servo pit pattern 3 by coating with aluminum, gold, platinum or the like. . In FIG. 3, the servo pit pattern 3 is formed on the entire surface of the first substrate 1, but may be formed periodically. The maximum height of the servo pit is 1750 mm (175 nm), which is sufficiently smaller than the thickness of the first substrate and other layers.
On the side where the servo pits are not provided on the first substrate, a dichroic mirror layer in which Ag is selectively deposited as the selective reflection layer 6 is provided.
A recording layer 4 is provided on the reflective film 2. An optical recording medium 21 is configured by sandwiching the selective reflection film 6 and the recording layer 4 between the first substrate 1 and the second substrate 5 (a polycarbonate resin substrate).
The pit pattern recording area has the same configuration as the volume holographic recording area except that a dye-containing recording layer is formed on the surface of the servo pit pattern 3.

  The optical recording medium 21 in the present embodiment may be disk-shaped or card-shaped. In this optical recording medium 21, the first substrate 1 has a thickness of 0.6 mm, the selective reflection layer 6 has a thickness of 20 to 30 μm, the holographic recording layer 4 has a thickness of 500 μm, and the second substrate 5 has a thickness of 0.6 mm. The total thickness is about 1.6 mm.

<Regeneration process and regeneration means>
The reproduction step reads the temperature correction information of the reproduction position before reproducing the information, and based on the temperature correction information, the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of information recording is Irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be in the range of −2 to + 2 ° C., and reproducing the information recorded on the holographic recording layer. Is called.

The difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is in the range of −2 to + 2 ° C., more preferably −1 to + 1 ° C., and −0.5 to + 0.5 ° C. Is more preferable. In this range, a good reproduced image can be obtained. If the adjusted temperature is outside the range of −2 to + 2 ° C. with respect to temperature information during recording, a reproduced image may not be obtained properly.
In this case, it is preferable to reproduce the recorded information by irradiating the interference pattern with the reference light at the same angle as the reference light used for recording on the optical recording medium.
During playback, after reading the temperature correction information including the recording position and temperature information of the playback position before playing back the information, the optical recording medium is adjusted to an appropriate temperature condition while collating with the positional information on the optical recording medium. Information is reproduced.
A method for adjusting the temperature of the optical recording medium (a method for changing the temperature) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is cooled by a Peltier element or other cooling means, or by infrared rays. Heating, heating, heating with a thermal head, etc. are mentioned.

  Here, FIG. 4 is a flowchart showing a recording / reproducing method of a conventional normal optical recording medium. First, when recording information, the position information recorded on the optical recording medium is read, and then the information is recorded on the optical recording medium. When information is reproduced, position information reproduced from the optical recording medium is detected, and then information is reproduced from the optical recording medium.

FIG. 5 is a flowchart showing the recording / reproducing method of the optical recording medium of the present invention. First, when recording information, the position information recorded on the optical recording medium is read, the temperature before recording is measured by the temperature correction information acquisition means, and the temperature information is recorded. Next, information is recorded on the optical recording medium, the temperature at the time of recording is measured by the temperature correction information acquisition means, and the temperature information is recorded. The position information and temperature information of these recording areas are recorded and stored.
Next, when reproducing information, first, position information to be reproduced by the optical recording medium is read, position information of the reproduction area is inquired, and temperature information is read. Next, the reproduction temperature condition is determined, and the temperature of the optical recording medium is adjusted. Next, the temperature of the optical recording medium is measured by the temperature correction information acquisition unit, and it is determined whether or not the intended temperature condition is in the range of −2 to + 2 ° C. with respect to the temperature information at the time of recording. If the intended temperature condition is satisfied, the reproduction of information is actually performed, and the reproduction is terminated when the reproduction is appropriate. If the intended temperature condition is not met, the temperature is adjusted again. Here, it is preferable to determine whether or not the intended temperature condition is satisfied by measuring the temperature of the optical recording medium using the temperature correction information acquisition unit.
As described above, information of the same quality as originally recorded information can be reproduced stably and promptly regardless of external temperature conditions.

Here, the recording method and the reproducing method of the optical recording medium of the present invention are performed using the optical recording / reproducing apparatus of the present invention described below.
FIG. 6 is a schematic diagram showing an example of the optical recording / reproducing apparatus of the present invention. The optical recording / reproducing apparatus shown in FIG. 6 is an example using an infrared laser non-contact meter as temperature measuring means. At the time of information recording, the information recording area 105 of the optical recording medium 106 is irradiated with the information light and the servo light 104, and the information recording area 105 is irradiated with the infrared laser 101 and the light reflected from the area is reflected by the infrared laser receiving unit. The temperature at the time of information recording in the information recording area 105 can be measured by receiving and analyzing the light.

FIG. 7 is an overall configuration diagram of an optical recording / reproducing apparatus according to an embodiment of the present invention. Although not shown, this optical recording / reproducing apparatus is provided with a temperature correction information acquisition device as shown in FIG. 6 as temperature correction information acquisition means, and an optical recording mechanism as a temperature adjustment mechanism. A Peltier cooling element and an electric heater are provided in a closed space where the medium is stored and recording / reproducing is performed, and temperature information of the reproduction position of the optical recording medium is read in advance, and the temperature in the closed space is appropriately controlled. Thus, the information recorded on the holographic recording layer at a temperature adjusted so that the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is in the range of −2 to + 2 ° C. It can be played.
This optical recording apparatus 100 controls a spindle 81 to which the optical recording medium 20 is attached, a spindle motor 82 for rotating the spindle 81, and the spindle motor 82 so as to keep the rotational speed of the optical recording medium 20 at a predetermined value. And a spindle servo circuit 83.
The optical recording / reproducing apparatus 100 records information by irradiating the optical recording medium 20 with information light and reference light, and irradiates the optical recording medium 20 with reproduction reference light, A pickup 31 for detecting and reproducing information recorded on the optical recording medium 20 and a drive device 84 that enables the pickup 31 to move in the radial direction of the optical recording medium 20 are provided.

  The optical recording / reproducing apparatus 100 uses a detection circuit 85 for detecting a focus error signal FE, a tracking error signal TE, and a reproduction signal RF from an output signal of the pickup 31, and a focus error signal FE detected by the detection circuit 85. Based on this, the actuator in the pickup 31 is driven to move the objective lens (not shown) in the thickness direction of the optical recording medium 20 to perform focus servo, and the tracking error signal detected by the detection circuit 85. Based on TE, a tracking servo circuit 87 that drives an actuator in the pickup 31 to move the objective lens in the radial direction of the optical recording medium 20 to perform tracking servo, a tracking error signal TE, and a command from a controller to be described later. Drive 84 controlled by a and a slide servo circuit 88 for performing a slide servo for moving the pickup 31 in the radial direction of the optical recording medium 20.

The optical recording / reproducing apparatus 100 further decodes output data of a later-described CMOS or CCD array in the pickup 31 to reproduce data recorded in the data area of the optical recording medium 20 or reproduce from the detection circuit 85. A signal processing circuit 89 that reproduces a basic clock and discriminates an address from the signal RF, a controller 90 that controls the entire optical recording / reproducing apparatus 100, and an operation unit 91 that gives various instructions to the controller 90 It has.
The controller 90 inputs the basic clock and address information output from the signal processing circuit 89, and controls the pickup 31, spindle servo circuit 83, slide servo circuit 88, and the like. The spindle servo circuit 83 receives the basic clock output from the signal processing circuit 89. The controller 90 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), and the CPU executes a program stored in the ROM using the RAM as a work area. The function of the controller 90 is realized.

  The optical recording / reproducing apparatus used in the recording method and the reproducing method of the optical recording medium of the present invention has temperature correction information acquisition means that can accurately grasp temperature information at the time of recording information, and an appropriate temperature at the time of reproducing information. Since it can be adjusted to the conditions, even when using a holographic optical recording medium, it is possible to reproduce information of the same quality as the originally recorded information stably and quickly, regardless of external temperature conditions. .

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Production Example 1)
-Production of optical recording media-
An optical recording medium having a volume holographic recording area and a pit pattern recording area was produced as follows.

--- Production of first substrate--
As the first substrate, a general polycarbonate resin substrate used for DVD + RW having a diameter of 120 mm, an inner diameter of 15 mm, and a plate thickness of 0.6 mm was used. A servo pit pattern is formed on the surface of the substrate, the track pitch is 0.74 μm, the groove depth is 140 nm, and the groove width is 300 nm.

--- Production of second substrate--
A second substrate made of polycarbonate resin having a diameter of 120 mm, an inner diameter of 15 mm, and a thickness of 0.6 mm was produced.

First, a reflective layer was formed on the servo pit pattern surface of the first substrate. Silver (Ag) was used as a material for the reflective layer, and an Ag reflective layer having a thickness of 150 nm was formed by DC magnetron sputtering.
Next, an organic dye (cyanine dye) represented by the following structural formula is formed in a non-masking area (pit pattern recording area) in a state where an adhesive sheet is pasted and masked on an area having an outer diameter of 120 mm to an inner diameter of 40 mm on the reflective layer. And p-dimethoxytetracyanoquinodimethane as an anti-fading agent in an amount of 10% by weight of the organic dye, and a solid content concentration of 2.5% by weight, dissolved in 2,2,3,3-tetrafluoropropanol. A coating solution was prepared. The coating solution was spin coated on the substrate and dried at 90 ° C. for 30 minutes to form a dye-containing recording layer having a thickness of 200 nm.

Next, the pressure-sensitive adhesive sheet was peeled off, and a UV curable resin (SD640: manufactured by Dainippon Ink & Chemicals, Inc.) was spin coated on the entire surface to form a first gap layer having a thickness of 20 μm.
On the obtained 1st gap layer, the selective reflection layer produced as follows was provided.
−Preparation of selective reflection layer−
First, a dichroic mirror layer made of an Ag film having a layer number of 30 and a thickness of 3 μm is formed by vapor deposition on a polycarbonate film (trade name Iupil, manufactured by Mitsubishi Gas Chemical Co., Ltd.) with a thickness of 100 μm by DC magnetron sputtering. In order to laminate on one substrate, the disc was punched into the same shape as the first substrate.

Next, as a protective layer (second gap layer), a UV curable resin (SD640: manufactured by Dainippon Ink & Chemicals, Inc.) was applied onto the selective reflection layer by spin coating so as to have a thickness of 20 μm.
Next, a spacer made of PET resin having an outer diameter of 40 mm, an inner diameter of 15 mm, and a thickness of 500 μm is sandwiched so that the inner diameter matches the inner diameter of the first substrate and the second substrate, as shown in FIG. 1 and the second substrate 5 were bonded to each other through a spacer 10. At this time, the first substrate 1 was bonded so that the side on which the selective reflection layer, the protective layer, and the like were laminated was the inside of the bonding.
The first substrate and the second substrate connected by the spacer at an interval of 500 μm are fixed in parallel from above and below, and in the gap between the two substrates, a Posilatio (liquid mixing injection device available from Liquid Control) The following holographic recording layer coating solution was filled and cured. Thus, an optical recording medium of Production Example 1 as shown in FIG. 1 was produced.

-Preparation of holographic recording layer coating solution-
Recording layer coating solutions having the following compositions were prepared in a tank A and a tank B, respectively, and each was prepared in a nitrogen atmosphere.
<Composition of recording layer coating solution>
[Tank A]
-Biuret trimer of hexamethylene diisocyanate ... 292.0g
・ Hexamethylene diisocyanate 97.4g
・ Tribromophenyl acrylate 64.22g
・ Irgacure 784 ... 14g
・ 3,5 ditertiary butyl-4-hydroxytoluene ... 210g
[Tank B]
・ PolyFoxTMT ・ ・ ・ 817.9g
-Polypropylene oxide triol (average molecular weight 1,000) ... 517.9 g
・ Tertiary butyl peroxide ・ ・ ・ 580μl
・ Dibutyl laurate tin ... 10.2g

(Examples 1 to 21)
-Recording information on the recording layer-
A collinear optical information recording / reproduction evaluation apparatus (manufactured by Pulse Tech Co., Ltd., SHOT-1000) having an infrared laser non-contact thermometer as shown in FIG. 6, a temperature control mechanism, and a non-contact type Using the modified device A-1 provided with a mechanism capable of measuring the temperature at the time of recording with a thermometer, the optical recording medium obtained in Production Example 1 was irradiated, and the temperature conditions at the time of recording were as shown in Table 1. The information was recorded on the holographic recording layer. At this time, the recording position of the information recording performed on the corresponding optical recording medium using the general-purpose DVD data recording / reproducing apparatus for the dye-containing recording layer of the optical recording medium of Production Example 1 and measurement at the time of recording are performed. Temperature correction information such as the recorded temperature was recorded.

<Reproduction signal evaluation>
Next, after removing the optical recording medium on which the information is recorded, the temperature correction information previously recorded on the dye-containing machine recording layer is again recorded on the general-purpose DVD data using the above-described remodeling apparatus A-1. The reproduction condition setting process shown in FIG. 5 was performed using the temperature correction information obtained by the apparatus, and the information was reproduced and the S / N ratio was measured. The results are shown in Table 1.

(Comparative Examples 1-6)
As Comparative Examples 1 to 6, using a collinear optical information recording / reproduction evaluation apparatus A-2 (manufactured by Pulstec Corporation, SHOT-1000) as shown in FIG. As shown, the information was reproduced by changing the temperature conditions during reproduction, and the S / N ratio was measured. The results are shown in Table 1.

From the result of Table 1, Examples 1-21 uses reproduction evaluation machine A-1, and the difference of the temperature of the optical recording medium at the time of reproduction | regeneration and the temperature of the optical recording medium at the time of recording is -2 to +2 degreeC. It turns out that it is possible to reproduce | regenerate a signal with a high S / N ratio by staying inside. Further, from the results of Examples 10 to 21, it was found that the reproduction characteristics are not influenced by the external temperature during reproduction as long as the optical recording medium temperature is appropriately controlled.
On the other hand, from the results of Comparative Examples 1 to 6, it was confirmed that the signal was not properly reproduced when the temperature difference of recording and reproduction deviated from the specified range without correcting the optical recording medium temperature.

(Example 23 and Comparative Examples 8-9)
-Evaluation of randomness-
Next, 100 optical recording media prepared in Production Example 1 were prepared, and information was recorded on the recording layer by the method described above without attaching any identifiable mark such as a label on the optical recording medium. It was. At this time, the room temperature and the temperature of the optical recording medium at the time of recording were set at random in the range of 15 to 30 ° C. and the temperature of the optical recording medium in the range of 25 to 40 ° C. When the optical recording medium after recording is randomly taken out from 100 sheets of Example 1 and 100 sheets of Comparative Example 1, respectively, and according to the performance evaluation method described above, when using the reproduction evaluator A-1, After reproducing the positional information and the recording temperature condition recorded in the dye-containing recording layer, the reproducing apparatus was adjusted to an appropriate temperature condition for reproduction, and the S / N ratio was measured (Example 22).
When the regeneration evaluation machine A-2 was used, regeneration was performed with the regeneration temperature fixed at 30 ° C., and the S / N ratio was measured (Comparative Example 7). Table 2 shows the number of optical recording media from which signals could be reproduced, the average value of S / N values, and the standard deviation when all 100 sheets were reproduced.

From the results shown in Table 2, an optical recording medium arbitrarily selected by recording the temperature correction information for each optical recording medium using the reproduction evaluator A-1 and reflecting the information on the reproduction conditions. In contrast, it is recognized that the signal can always be reproduced with a stable S / N ratio.

  In the optical recording / reproducing apparatus and the optical recording medium recording / reproducing method of the present invention, information of the same quality as originally recorded information can be reproduced stably and promptly regardless of the external temperature condition of the optical recording / reproducing apparatus. Therefore, it is widely used as various hologram type optical recording media capable of high sensitivity and high multiplex recording.

FIG. 1 is a schematic view showing an example of the optical recording medium of the present invention. FIG. 2 is a schematic view showing another example of the optical recording medium of the present invention. FIG. 3 is a schematic sectional view showing an example of a volume holographic recording area in the optical recording medium of the present invention. FIG. 4 is a flowchart showing an example of a conventional recording / reproducing method for an optical recording medium. FIG. 5 is a flowchart showing an example of the recording / reproducing method of the optical recording medium of the present invention. FIG. 6 is a schematic diagram showing an example of the optical recording / reproducing apparatus of the present invention. FIG. 7 is a block diagram showing an example of the overall configuration of the optical recording / reproducing apparatus of the present invention on which the optical recording medium of the present invention is mounted. FIG. 8 is a schematic view showing a method for bonding the first substrate and the second substrate in the optical recording medium of Production Example 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st board | substrate 2 Reflective film 3 Servo bit pattern 4 Holographic recording layer 5 2nd board | substrate 6 Selective reflection layer 7 2nd gap layer 8 1st gap layer 10 Spacer 20 Optical recording medium 31 Pickup 33 Servo light 35 Information light And reference light 35a information light and reference light 81 spindle 82 spindle motor 83 spindle servo circuit 84 drive device 85 detection circuit 86 focus servo circuit 87 tracking servo circuit 88 slide servo circuit 89 signal processing circuit 90 controller 91 scanning unit 100 optical recording / reproducing device DESCRIPTION OF SYMBOLS 101 Infrared laser 102 Infrared laser light-receiving part 103 Infrared laser beam 104 Information light, reproduction light, and servo light 105 Recording area 106 Optical recording medium 201 Volume holographic recording area 202 Pit pattern Recording area A Input / output surface FE Focus error signal TE Tracking error signal RF playback signal

Claims (9)

A recording means for recording information on the holographic recording layer by irradiating the optical recording medium with information light and reference light, and servo light;
Temperature correction information acquisition means for measuring and recording temperature correction information including at least a recording position of information on the optical recording medium and a temperature at the time of recording information when recording information;
The temperature correction information at the reproduction position is read before reproducing the information, and the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is based on the temperature correction information is in the range of −2 to + 2 ° C. And reproducing means for reproducing the information recorded in the holographic recording layer by irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be .   The optical recording / reproducing apparatus according to claim 1, wherein the temperature correction information acquisition unit includes a non-contact type thermometer that measures a temperature at the time of recording information.   The optical recording / reproducing apparatus according to claim 2, wherein the non-contact type thermometer is an infrared laser non-contact type thermometer.   4. The optical recording / reproducing apparatus according to claim 1, wherein the temperature correction information is recorded on the same optical recording medium as the optical recording medium on which the information is recorded.   The optical recording / reproducing apparatus according to claim 4, wherein the optical recording medium has a volume holographic recording area and a pit pattern recording area independently of each other.   6. The optical recording / reproducing apparatus according to claim 5, wherein the temperature correction information recorded in the pit pattern recording area is at least a recording position of the information recorded in the volume holographic recording area in the optical recording medium and a temperature at the time of recording the information. .   Irradiation of the information light and the reference light to the optical recording medium is performed so that the optical axis of the information light and the optical axis of the reference light are coaxial, and is generated by interference between the information light and the reference light The optical recording / reproducing apparatus according to claim 1, wherein information is recorded on the holographic recording layer by an interference pattern. A recording step of recording information on the holographic recording layer by irradiating the optical recording medium with information light and reference light, and servo light;
A temperature correction information acquisition step of measuring and recording temperature correction information including at least a recording position of information in the optical recording medium and a temperature at the time of recording information at the time of recording information;
The temperature correction information at the reproduction position is read before reproducing the information, and the difference between the temperature of the optical recording medium at the time of reproduction and the temperature of the optical recording medium at the time of recording is based on the temperature correction information is in the range of −2 to + 2 ° C. A reproducing step of reproducing information recorded on the holographic recording layer by irradiating the optical recording medium with reference light and servo light at a temperature adjusted to be Recording and playback method. Irradiation of the information light and the reference light to the optical recording medium is performed so that the optical axis of the information light and the optical axis of the reference light are coaxial, and generated by interference between the information light and the reference light The recording / reproducing method for an optical recording medium according to claim 8, wherein information is recorded on the holographic recording layer by the interference pattern.