JPH02168446A - Optical information recording medium - Google Patents

Abstract

PURPOSE:To obtain modulation of a reproducing signal suitable for a compact disk format by deforming a layer of a base adjacent to a light absorbing layer of a pit part so as to record the information. CONSTITUTION:When a laser beam 7 from a pickup 8 is converged and irradiates a light absorbing layer 2, the irradiated part absorbs the laser beam 7 and is heated, the irradiated part is molten and decomposed, and the base adjacent to the irradiated part or other layer 1 is softened and molten. Then part 12 of a cyanine group dystuff such as indodicarbocyanine being a constituent of the layer 2 is diffused or in viscous fluid into the layer 1, the content is mixed with the component of the layer 1 and combined partially. Thus, a projection deformed part 6 is formed to the surface of the layer 1. Then there exists a phase difference of light at between pits and other parts and a large difference in the reflected luminous quantity is caused in the laser beam. Thus, the modulation of the reproduced signal is increased and the result is in compliance with the format of the compact disk.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical information recording medium having bits recorded by laser light.

[Prior Art] An optical information recording medium capable of recording data by irradiation with laser light has a recording layer consisting of a metal layer of Tes Bis Mn1F, a dye layer of cyanine, merocyanine, phthalocyanine, etc. Bits are formed and data are recorded by deforming, sublimating, evaporating, or denaturing the recording layer by irradiating it with laser light. In an optical information recording medium having this recording layer, in order to facilitate deformation, sublimation, evaporation, denaturation, etc. of the recording layer when forming bits,
It is common practice to provide a void behind the recording layer. Specifically, for example, a stacked structure called an air sandwich structure is used, in which two substrates are stacked with a space in between.

In this optical information recording medium, bits are formed by irradiating laser light from the light-transmitting substrate l side. When reproducing the recorded data, a laser beam with a lower power than that during recording is irradiated from the substrate 1 side, and the signal is read based on the difference in reflected light between the bit and other parts.

On the other hand, so-called ROM type optical information recording media, in which data is recorded in advance and data cannot be written or erased afterwards, have already been widely used (practical) in the information processing and audio sectors. Bits for reproducing recorded data without the above-mentioned recording layer are formed in advance on a polycarbonate substrate by means such as pressing, and on this is a reflective layer made of a metal such as AuX Ags Cus At. A protective layer is formed on the protective layer.

The most typical type of ROM-type optical information recording medium is the compact disc, or so-called CD, which is widely used in the audio and information processing sectors.The specifications of the recording and playback signals of this CD are in the so-called CD format. It has been standardized as a compact disc player (CD player), and playback devices that comply with this standard have become extremely popular as compact disc players (CD players).

[Problems to be Solved by the Invention] It is strongly desired that the above-mentioned optical information recording medium be compatible with the already widely used CD and playable on a CD player.

However, the above-mentioned optical information recording medium has a recording layer that is not present in a CD, and uses a method of recording bits by forming them on the recording layer instead of on the substrate. Furthermore, since a gap layer and the like are grown in this recording layer to facilitate the formation of bits, the reproduced signal differs from that of a CD in terms of the laser beam reflection layer, the degree of modulation of the reproduced signal, etc. In particular, bits formed by laser beam irradiation are not as clear as bits formed mechanically, such as by pressing, and therefore it is difficult to achieve a large degree of modulation. For this reason, it is difficult to satisfy the above-mentioned CD t-mat, which defines the standard for so-called CDs, and it has not been possible to provide an optical disc that can be played on a CD player.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to provide an optical information recording medium that can obtain a reproduced signal with a modulation degree that can be adapted to the CD format. .

[Means for Solving the Problems] That is, in order to achieve the above object, the present invention first includes a light absorption layer that absorbs laser light directly or through another layer on a transparent substrate; In an optical information recording medium, a light reflecting layer that reflects laser light directly or through another layer is formed on the light absorption layer, and a bit for reproducing data by irradiation with laser light is formed. To provide an optical information recording medium in which a layer on a substrate side adjacent to a light absorption layer is deformed.

In this case, the deformation of the layer on the substrate side adjacent to the light absorption layer can generally be convex, wavy, or concave on the light absorption layer side. Further, in many cases, a layer of the substrate fli11 adjacent to the light absorption layer in the pit portion has an optical property modified portion where the optical properties are locally changed. Furthermore, voids may be formed at the interface between the light absorption layer in the pit area and another layer adjacent to the same layer, or fine air bubbles may be dispersed in the light absorption layer in the pit area. .

Second, the present invention includes a light absorption layer that absorbs laser light directly or through another layer on a transparent substrate, and a light absorption layer that absorbs laser light directly or through another layer on the light absorption layer. In an optical information recording medium in which a reflective light layer and pits for reproducing data are formed by irradiation with laser light,
An optical information recording medium is provided which has an optical property modified portion in which the optical properties are locally changed in a layer on the substrate side adjacent to the light absorption layer in the pit portion.

In this case, the optical property modification portion is generally formed in a layer on the substrate side adjacent to the light absorption layer, in which decomposed components of the light absorption layer are diffused.

[Function] In the optical information recording medium of the first means above, in the pit, the layer on the substrate side adjacent to the light absorption layer is locally deformed, so that the gap between the pit portion and the non-pit portion is A phase difference occurs between the two, and the incident laser spot is scattered, resulting in a large difference in the reflected light m of the laser beam. Therefore, the degree of modulation of the reproduced signal can be increased.

In this case, regardless of whether the deformation of the pit portion on the substrate side is convex, concave, or wavy toward the light absorption layer side, the above-mentioned effect is generally the same. Furthermore, in addition to the above-mentioned deformation in the bit part, the layer on the substrate side has a locally modified optical property region, where the optical property has changed locally.
If voids are formed at the interface between the light absorption layer and another layer adjacent to the same layer, or if fine bubbles are dispersed in the light absorption layer in the pit area, the phase difference of the laser spot due to these, Due to effects such as absorption and scattering, a large difference occurs in the amount of reflected laser light between the pit portion and the non-pit portion, and the degree of modulation of the reproduced signal can be increased.

Furthermore, in the optical information recording medium according to the second means, by having an optical property modified portion in which the optical properties are locally changed in the layer on the substrate side adjacent to the light absorption layer in the pit portion,
Due to the effects of phase difference, absorption, scattering, etc. of the incident laser light in the optical property modification part, a large difference occurs in the optical conditions between the part other than the pit and the part of the pit, especially in the reflection of the laser light. Similar to the first method, the degree of modulation of the reproduced signal can be increased.

In optical information recording media in which pits are formed by deforming the layer on the substrate side adjacent to the light-absorbing layer, a reflective layer can be provided closely behind the light-absorbing layer. Also, an optical information recording medium having a layer structure similar to that of a CD can be obtained, and in particular, a recordable optical 111 information recording medium whose reproduction signal when reading data conforms to the CD format can be easily obtained.

[Embodiments] Next, embodiments of the present invention will be described in detail with reference to the drawings.

Examples of the schematic structure of the optical information recording medium according to the present invention are shown in FIGS. 1 to 3. In the figure, 1 is a light-transmitting substrate, and 2 is a light-absorbing layer formed thereon, which absorbs irradiated laser light and generates heat, and also melts, evaporates, and This layer is sublimated, deformed, or denatured to form pits 5 at the positions irradiated with the laser spot. Figure 2 shows the state before recording with laser light, and Figure 3 shows the state after recording, that is, the optical pickup 8.
When the laser beam 7 is focused and irradiated onto the light absorption layer 2 from
A state in which the surface of the transparent substrate 1 is partially deformed and/or changed and pits 5 are formed is schematically shown.

When the light absorption layer 2 is irradiated with the laser beam 7, the irradiated portion absorbs the laser beam 7 and generates heat, and at the same time, the irradiated portion melts and decomposes, and at the same time, the layer adjacent thereto also softens and melts. Then, a part of the components constituting the light absorption WIJ2 diffuses or viscous flows into the layer adjacent to the same layer, and this mixes with the components of the layer on the transparent substrate 1 side adjacent to the light absorption layer 2,
Partially combined. Accordingly, a convex deformed portion 6 is formed on the surface of the layer adjacent to the light absorption layer 2. This phenomenon can occur, for example, when one layer adjacent to the light absorption layer 2 is made of gold.
In the case where the light reflecting layer 3 is made up of four layers and the other adjacent layer is the light-transmitting substrate 1 made of a resin layer, it tends to occur mainly on the light-transmitting substrate 1 side, but when the light-absorbing layer 2 and the light-absorbing layer 2 The deformation on the interface side is due to light reflection W! This may also occur on the J3 side. Note that the deformed portion 6 may be wavy toward the light absorption FJ2 side, or may be concave in some cases.

The transparent substrate 1 is made of a material that is highly transparent to laser light and is mainly made of resin with excellent impact resistance, such as a polycarbonate plate, an acrylic plate, an epoxy plate, or the like.

The light absorbing WJ2 absorbs the laser beam incident from the transparent substrate 1 side, generates heat, and melts and decomposes. It is formed by a spin code method or the like via another layer formed thereon. The reflective layer 3 is formed of a metal film, for example, gold, silver, copper, aluminum, or an alloy film containing these. The protective layer 4 is formed of a resin with excellent impact resistance similar to that of the transparent substrate 1, and most commonly, an ultraviolet curable resin is applied by a spin code method and cured by irradiating it with ultraviolet rays. It is formed by In addition, epoxy resins, acrylic resins, silicone hard coat resins, etc. are commonly used.

In the optical information recording medium according to the present invention, the real part nab of the complex refractive index of the light absorption layer 2 and its film thickness d a
ρ” n ab given by the wavelength λ of the reproduction light
It is desirable that s d sbm/λ satisfies 0,055/:l≦0゜6, and the imaginary part 1 (abs) of the complex refractive index is 0.3 or less. If the above conditions are satisfied,
A high reflectance can be obtained, and the standard characteristics specified for the CD format, which is a reflectance of 70% or more, can be sufficiently ensured.

FIGS. 4 to 8 schematically show examples of the states of the above-mentioned bits 5 formed by laser beam irradiation.

FIG. 4 schematically shows a state in which deformation 6 has occurred in the substrate 1 adjacent to the light absorption layer 2 by irradiating the light absorption layer 2 with a spot of laser light 7 at the bit 5 part. .

To explain this more specifically, FIG. 4(a) shows that when the light absorbing JI 12 is irradiated with a laser spot, the components of the same layer 2 are melted and decomposed, and the light absorbing material of the transparent substrate 1 is melted and decomposed. The interface side with layer 2 is softened, and as a result, the light absorption layer 2
This diagram schematically shows a case where a deformation 6 is formed due to the components of 1 being diffused or viscous flowing toward the transparent substrate l.

At the same time, the components of the light-absorbing layer 2 are locally mixed with the material constituting the light-transmitting substrate l, and are partially combined, so that the light-absorbing layer 2 and the light-transmitting substrate l are partially combined. It is often the optical property modification portion 12 that has different optical properties.

For example, when the light absorption layer 2 is formed of a cyanine-based dye and the transparent substrate l is formed of polycarbonate, the optical characteristics of the optical property modification portion 12 have values that are slightly different from those of the transparent substrate l. Become.

When a laser spot is irradiated onto the light absorption layer 2 in order to form the bit 5, the components forming the light absorption layer 2 locally generate heat, melt, and decompose at that part, so that the optical absorption layer 2 is Characteristics also typically vary locally. Furthermore, as a result of this phenomenon, physically, as shown in FIG. 4(b), the interface between the light absorbing layer 2 and other layers adjacent thereto, such as the light reflecting layer 3, peels off, leaving voids there. Part 1O may be formed, or bubbles may be generated in the light absorption layer 2, and these may remain even after cooling.

The above-mentioned void 10 is formed by forming a layer adjacent to the side of the light absorption layer 2 on which the laser beam 7 is incident, for example, a layer adjacent to the substrate l side.
It can be formed when the layer behind the layer, for example, the light reflective layer 3 and the protective layer 4, is more easily thermally deformed than the latter, and the latter has poorer adhesiveness with the light absorbing layer 2 than the former. That is, in such an optical information recording medium, when the light absorption layer 2 is irradiated with the laser beam 7, energy is generated in the light absorption layer 2 as described above, and at the same time, the substrate 1 is deformed 6. This is thought to occur because gas is generated in the light absorption layer 2, which causes the interface between the light absorption layer 2 with poor binding properties and the adjacent light reflection layer 3 to separate, and gas to accumulate there. . In addition, the gas generated inside the light absorption layer 2 has bubbles 1
1 and remain.

Figures 4 (C) and (d) show other shapes of the deformation 6 on the transparent substrate l side, and (C) shows a state in which the convex top of the deformation 60 is broken into two. (d) shows a wavy deformation 6 in which unevenness is alternately repeated. In these cases as well, the above-mentioned voids 10, bubbles 11, and optically modified portions I2 may be formed.

In FIG. 8, in order to form a bit 5 along a pre-groove 13 which is a tracking means formed on the surface of a transparent substrate 1, a CD signal is applied to a light absorption layer 2 along the pre-groove 13. After irradiation with a modulated laser spot, the protective layer 4 and the light reflection layer 3 are peeled off from the transparent substrate 1, and the light absorption layer 2 is further removed from the surface of the same substrate 1, which is schematically shown. .

Furthermore, S TM (Scanning Tunneli
FIG. 9 shows an example in which the state of the surface of the transparent substrate l along the pre-groove 13 was observed using a NG Microscope. In the figure, the horizontal axis represents the moving distance of the tip (probe) 14 in the direction along the pregroove 13, that is, the tracking direction, and the vertical axis represents the height of the surface of the transparent substrate l. Figure (a) shows the case where the bit distance is relatively short at 10,000 angstroms.
It can be seen here that a clear convex deformation 6 with a height of about 200 angstroms is formed. In addition, Figure (b) shows the case where the bit distance is relatively long at 40,000 angstroms, and here a convex deformation 6 with a height of about 200 angstroms is recognized, but the middle part of this deformation is slightly lower. It can be seen that the peak of deformation 6 is divided into two.

FIG. 5 schematically shows a case where the deformation 6 of the light-transmitting substrate 1 adjacent to the light-absorbing layer 2 in the bit 50 portion is formed in a concave shape with respect to the light-absorbing layer 2.

FIG. 5(a) shows a case where a void IO is formed at the boundary between the light absorption layer 2 and the light reflection layer 3, and FIG.
At the same time as the above-mentioned voids 1O are formed, fine bubbles 11°11... are dispersed in the light absorption layer 2, and further deformation 6
The decomposed components of the light-absorbing layer 2 are diffused into the transparent substrate 1 on which the transparent substrate 1 is formed, and this component and the components constituting the transparent substrate 1 are mixed and partially combined, resulting in an optical property modification portion. 12 is formed. Furthermore, FIG. 1C shows a case where a gap lO'' is formed between the substrate 1 and the light absorption layer 2 at the same time as the gap 10 is formed.

FIG. 6 shows the case where the deformation 6.6' in bit 5 extends to both layers adjacent to light absorbing layer 2.

Such a bit is often formed when the layers on both sides of the light absorbing layer 2, for example, the substrate 1, the light reflecting layer 2, and the protective layer 4, have approximately the same heat deformation temperature or hardness.

In FIG. 6(a), in the bit 5, the light absorption layer 2
In the case where a gap lO' is formed between the light absorbing layer 2 and the substrate 1, FIG.
10 and 10' are formed in both the light absorbing layer 2 and
The cases where 1... are dispersed are shown respectively. FIG. 6(d) shows deformation 6.6 of the light-transmitting substrate l and the light-reflecting layer 3 side.
' are both formed in a convex shape toward the light absorption layer 2 side.

Further, FIG. 7 shows a case in which an optical characteristic modified portion 13 having optical characteristics different from other portions in a bit 50 portion is grown in the layer 0111 on which the laser beam 7 is incident on the light absorption layer 2. be. This modified portion 13 is always located on the laser beam 70 incidence side, and often extends into the interior of the light absorption layer 2. In this case, deformation 6 of the layer adjacent to the light absorption layer 2 may be observed, but the deformation is generally unclear due to the presence of the optical property modification portion 13.

FIG. 7(a) shows, for example, a substrate l adjacent to the light absorption layer 2.
It shows a state in which the optical property modification part 13 is formed in the part,
FIG. 2B shows a state in which the optical characteristics gradually change in the thickness direction from the substrate 1 to the light absorption layer 2.

Such modification of each layer is caused by decomposition, reaction, and interdiffusion of the light absorption layer 2 and other layers due to the action of heat generated when the light absorption layer 2 is irradiated with the laser beam 7. Therefore, such pits 5 are located between the light absorption layer 2 and this?
This is formed when a material having such an effect is selected for the adjacent layer.

Further, a concrete example 1 of the present invention will be explained below.

(In the example, the surface has a width of 0.8 μm, a depth of 0.08 am, and a pitch of 1
．． Thickness 1. In which spiral pregroove 8 of 6 μm is formed. 2mm5 Outer diameter 120mmφ, inner diameter 15m
A polycarbonate lambda plate l of mφ was molded by injection molding. The Rockwell hardness ASTM D785 of this polycarbonate substrate is M2S (equivalent to pencil hardness HB)
The heat distortion temperature ASTM D648 is 4°6k
g/am', 121'C.

As an organic dye for forming light absorption WB2, 0.6
5g l,1'dibutyl3. 3. 3'31 tetramethyl4. 5. 4', 5' dibenzoindodicarbocyanine perchlorate (Japan Photosensitive Pigment Research Institute,
Product number NK3219) in diacetone alcohol solvent 10
c cJ was dissolved and applied to the surface of the above-mentioned substrate 1 by a spin-free method to form a light absorption layer 2 with a thickness of 130 nm.

Next, a single layer of Au with a thickness of 80 nm was deposited on the entire surface of the disk with a diameter of 45 to 118 mmφ by sputtering.
A reflective layer 3 was formed by copying the film. Furthermore, an ultraviolet curable resin was spin-coded on the reflective layer 3 and cured by irradiating ultraviolet rays to form a protective layer 4 having a thickness of 10 μm. Rockwell hardness A after curing of this protective layer 4
STM D785 is M2O, heat distortion temperature AST
MD848 is: 4. s+<g,"cm2.1
The temperature was 35°C.

A semiconductor laser with a wavelength of 780 nm was applied to the optical disc thus obtained at a linear velocity of 1.2 m/see.

Irradiation was performed at a recording power of 6.0 mW, and an EFM signal was recorded. Thereafter, this optical disc is transferred to a commercially available CD player CA.
urex XR-V73, wavelength λ of reproduction light = 780n
m), the reflectance of the semiconductor laser was 72%.
, Iz/It. .

is 0.68, I3/Is. . was 0.35, and the block error rate BLER was 1.2X10-2.

According to the CD standard, the reflectance is 70% or more, I, 1/I. ,
is 0.6 or more, I3/It. , is defined as 0.3 to 0°7, and the block error rate BLER is defined as 3XJ0-2 or less, and the optical disc according to this embodiment satisfies these standards.

Furthermore, the protective layer 4 and light reflective layer 3 of the optical disc after recording are peeled off, and the light absorbing layer 2 is washed and removed with a solvent.
The surface of the transparent substrate 1 is subjected to STM (Scanning Tube).
When observed with a cutting microscope, a convex deformation was observed in the pit portion. moreover,
When the recorded and unrecorded portions of the substrate 1 were measured using a spectroscopic altimeter, peaks were observed in the recorded portion in addition to the resin peak seen in the unrecorded portion.

(Example 2) Example 1 is the same as Example 1 above, except that a hard layer of 1100 nm thick is provided between the light absorption layer 2 and the light reflection layer 3 by spin-coating an epoxy resin. An optical disc was produced in the same manner. The Rockwell hardness ASTM D785 after curing of this epoxy resin is M2O, and the heat distortion temperature ASTM D648 is 4.6 kg.
/cm'% was 135°C.

EFM signals were recorded on the thus obtained optical disc in the same manner as in Example 1, and then this optical disc was
When played back on a commercially available CD player, the same reflectivity and playback signal output characteristics of the semiconductor laser as in Example 1 were obtained, and the block error (BLER) was 3.0×.
It was l0-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm lining microscope, a convex deformed portion 6 was observed. This deformed part 6
It was confirmed that the middle part of the curve is slightly lower, and the peak of deformation is divided into two.

(Example 3) In the above Example 1, instead of the epoxy resin formed on the upper surface of the light absorption layer 2 between the light absorption layer 2 and the light reflection WJ3, a hard layer of silicon acrylic resin with a thickness of 1100 nm is formed. 2 made of epoxy resin is provided on the upper surface of this hard layer.
Optical disks were manufactured in the same manner as in Example 1 above, except that a 0 nm binding layer was formed by the spin code method. The Rockwell hardness ASTM D785 of the silicon acrylic resin layer after curing is Mloo, and the heat distortion temperature ASTM D648 is 4. 6kg/
cm2.100°C.

EFM signals were recorded on the thus obtained optical disc at a recording power of 7.0 mW in the same manner as in Example 1, and then this optical disc was placed in the same CD player as in Example 1 (Aurex XR-V73, with a reproduction light beam of Wavelength 780n
When 1Y was generated at m, the reflectance of the semiconductor laser was 75%.
,■eye/It1. =0.63, I3/It. , is 0.
35. Block error rate BLER is 2.5XlO°
It was 3.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 4) In the above Example 1, on the light absorption ff2, the light reflection n
3, an alloy film of gold and antimony in a ratio of 9:1 was formed by a vacuum pre-deposition method, and on this reflective layer 3,
An optical disc was manufactured in the same manner as in Example 1 above, except that the protective layer 4 made of ultraviolet curable resin was formed via a 20 nm binding layer made of epoxy resin. In addition,
The light reflecting layer 3 has a pencil hardness of rHJ or more.

EFM signals were recorded on the optical disc thus obtained at a recording power of 8.2 mW in the same manner as in Example 1, and then this optical disc was played back using the same CD player as in Example 1. rate is 72%, I
z/It. .

is 0.62. Is/It. , was 0.32) and the block error rate BLER was 3.5XIO-''.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
As a result of observation using an old microscope, the same condition as in Example 1 was confirmed.

(Example 5) In Example 1 above, an ultraviolet curable hard coat resin was spin-coded on the light incident side of the polycarbonate substrate 1, a substrate protective layer with a thickness of 1 μm was provided, and a light The absorption layer 2 is formed, and on this light absorption layer 2, a light reflection layer 3 of 3= of iridium and gold is formed.
An optical disc was manufactured in the same manner as in Example 1 above, except that the alloy film having a ratio of 1:1 was formed by sputtering. The light reflecting layer 3 has a pencil hardness of "5".
It has a hardness of H" or higher.

EFM signals were recorded on the thus obtained optical disc in the same manner as in Example 1, and then this optical disc was
When reproduced using the same CD player as in Example 1, the reflectance of the semiconductor laser was 70%, f++/It. , is 0.
62.13/1top was 0.37, and the block error rate BLER was 3.7X10-''.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 6) In Example 1 above, the light reflection layer 3 was formed of a silver film with a thickness of 60% m, and a silicone hard coating agent was spin-coded on L, and this was heated and cured. Thickness 3
An optical disc was manufactured in the same manner as in Example 1 above, except that the hard protective layer 4 having a thickness of μm was formed. The protective layer 4 has a pencil hardness equal to or higher than rHBJ.

, EFM signals were recorded on the thus obtained optical disk in the same manner as in Example 1, and then this optical disk was played back using the same CD player as in Example 1. When the reflectance of the semiconductor laser was 71%, I++ /Itop is 0.
63, I3/lt. - was 0.35, and the block error rate BLER was 2.8×10''.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
nne! As a result of observation using a microscopic microscope, the same condition as in Example 1 was confirmed.

(Example 7) In the above Example 1, a 50 nm thick Au film was placed on the light reflection layer 3, which was vacuum-deposited, with Borisulf® diluted with diglycidyl ether. A hard protective layer 4 with a thickness of 3 μm was formed by spin-coding a silicone hard coating agent through a 30% m thick condensed layer formed by spin-coding an epoxy resin containing light, and heating and curing this. An optical disc was manufactured in the same manner as in Example 1 above.

EFM signals were recorded on the thus obtained optical disc in the same manner as in Example 1, and then this optical disc was
When played back using the same CD player as in Example 1, the reflectance of the semiconductor laser was 72%, Natsume/It6. is 0.65.
13/l. .

is 0.35, block error rate BLER is 2.5X
It was 10-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 8) In the above Example 1, l, 1' dibutyl 3.3
．． The light absorption layer 2 was formed using 3'3' tetramethyl 5.5' diethoxy indodicarbocyanine iodide, and the 1100 nm hard layer made of epoxy resin was formed on the second side of the light reflection layer 3. Furthermore, 108 m of ultraviolet curing resin was provided on top of this to form the protective layer 4.
An optical disc was manufactured in the same manner as in Example 1 above.

EFM signals were recorded on the thus obtained optical disc in the same manner as in Example 1, and then this optical disc was
When reproduced using the same CD player as in Example I, the reflectance of the semiconductor laser was 74%, I++/It. , is 0.
68, I3/It. .

is 0.34, block error rate BLER is 8.3X
It was 10-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 9) In the above Example 1, except that polycarbonate], (an ultraviolet curable hard coat resin was spin-coded on the light incident side of the plate 1 and a substrate protective layer with a thickness of 1 μm was provided.
An optical disc was manufactured in the same manner as in Example 1 above.

EFM signals were recorded on the thus obtained optical disc in the same manner as in Example 1, and then this optical disc was
When reproduced using the same CD player as in Example 1, the reflectance of the semiconductor laser was 70%, r++/It. , is 0.
62. li/I,. , is 0.37, block error rate
1-BL ER was 1.3×10”.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 10) In Example 1 above, except that a polybutadiene resin layer with a thickness of 10% m was provided between the light absorption layer 2 and the reflection layer 3 by spin-coding polybutadiene resin dissolved in cyclohexane. An optical disc was manufactured in the same manner as in Example 1 above.

EFM signals were recorded on the thus obtained optical disc in the same manner as in Example 1, and then this optical disc was
When reproduced using the same CD player as in Example 1, the reflectance of the semiconductor laser was 72%, I++/It. , is 0.
65.13/1. , was 0.35, and the block error rate BLER was 8.6X10-''.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 11) An acrylic resin dissolved in diisobutyl ketone was spin-coded onto the surface of the same polycarbonate substrate 1 used in Example 1 to form a 40 nm thick resin layer (not shown).

The Rockwell hardness ASTM D785 of this resin layer is M2S, and the heat distortion temperature ASTM D648 is 4.
6 kg/cm2.100°C.

0.6g as an organic dye for forming the light absorption layer 2
1.1' dipropyl, 3. 3. 3'3'tetramethyl 5.5' dimethoxyindodicarbocyanine iodide was dissolved in isopropyl alcohol solvent 10c.
c and coated on the surface of the above-mentioned substrate l by a spin code method to form a light absorption layer 2 with a thickness of 120 nm.

ρ” given by the real part nabs of the complex refractive index of the light absorption layer 2, its film thickness d abs and the wavelength λ of the reproduction light.
nabsdal+s/λ was 0.41, and the imaginary part k abs of the complex refractive index was 0.02.

Next, a silicone acrylic resin dissolved in cyclohexane was spun onto this to form a hard layer having a thickness of 1100 nm. This hard layer has a hardness of 2H and a heat distortion temperature of A.
STM D6484.8kg/cm", 120°C. A film thickness of 50°C was formed on the hard layer by sputtering.
A reflective layer 3 was formed by depositing a nm thick Au film. moreover,
An ultraviolet curable resin was spin-coded on the reflective layer 3 and cured by irradiating ultraviolet rays to form a protective layer 4 with a thickness of 10 μm. The Rockwell hardness ASTM D785 after curing of this protective layer 4 is M2O, and the heat distortion temperature ASTM D648 is 4.6 kg/c.
m2, 135°C.

A semiconductor laser with a wavelength of 780 nm was applied to the optical disc thus obtained at a linear velocity of 1.2 m/5ecs and a recording power of 7.5 m.
It was irradiated with W and the EFM signal was recorded. Thereafter, when this optical disc was played back on the same CD player as in Example 1, the reflectance of the semiconductor laser was 74%, I++/It. ,
was 0.82, I3/I top was 0.31, and block error rate BLER was 4.0X10-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 12) Example 1 above! In the same manner as in Example 11, except that a silicone coating agent was spin-coated on the resin layer to form a silicate a having a thickness of 0°01 μm, and a light absorption layer 2 was formed thereon. Created an optical disc.

An EFM signal was recorded on the thus obtained optical disc at a recording power of 7.8 mW in the same manner as in Example 11, and
After that, when this optical disc was played back on the same CD player as in Example 11, the reflectance of the semiconductor laser was 73%.
,I,,/1,. , is 0.62) Ia/L. , is 0.3
1. Block error rate BLER is 3.4XlO
-3.

Further, in the same manner as in Example I above, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 13) In Example 11 above, a glass substrate was used as the substrate l, and an isocyanate resin dissolved in a l:l solvent of toluene and methyl ethyl ketone was formed on the reflective layer by a spin coding method. In the same manner as in Example IT above, except that a binding layer with a thickness of 20% m was formed.
Created an optical disc.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.2 mW in the same manner as in Example 11, and
After that, when this optical disc was played back on the same CD player as in Example 11, the reflectance of the semiconductor laser was 72%.
,l,,/1,. , is 0.65, la/L0- is 0.3
3. Block error rate) BLER was 3.6XIO bow.

Further, in the same manner as in Example 1 above, the surface of the transparent substrate I of the optical disc after recording was coated with STM (SCannig Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 14) In Example 11 above, a silicate layer with a thickness of 0°018 m was provided on the resin layer by spin-coating a silicone coating agent, and a light absorption layer 2 was formed on the silicate layer. An optical disc was manufactured in the same manner as in Example 11, except that a 20% thick binding layer made of polybutadiene by spin-coding was formed on the light-reflecting layer 3.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.2 mW in the same manner as in Example 11, and
After that, when this optical disc was played back on the same CD player as in Example 11, the reflectance of the semiconductor laser was 72%.
,lz/1,. , is 0.66, Is/It. , is 0.3
5. Block error rate BLER was 3.5X]O''.

Further, in the same manner as in Example 1, the surface of the transparent substrate 10 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 15) In Example 11 above, the thickness of the resin layer was 20% m, the silicon acrylic resin layer was not provided, and the reflective layer 3 was an alloy film of iridium and gold at a ratio of l: 9. An optical disc was manufactured in the same manner as in Example 11 above, except that it was formed by sputtering. The pencil hardness of Alloy 1 was 2H.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.0 mW in the same manner as in Example 11, and
Thereafter, when this optical disk was played back on the same CD player as in Example If, the reflectance of the semiconductor laser was 71.
%, I+1/1,. . is 0.63, and L/Ito- is 0.
32) Block error rate) BLER is 3.3XIO-
'Met.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 16) The above example! In (j), a silicate layer with an Ip diameter of 0°01 μm was formed by spin-coating a silicone coating agent on L of the fat layer, and a light absorption layer 2 was formed on it, and a silicone acrylic resin layer was formed. An optical disk was manufactured in the same manner as in Example 11, except that the reflective layer 3 was formed using an alloy film of iridium and gold in a ratio of 120 by sputtering.

An EFM signal was recorded on the thus obtained optical disc at a recording power of 7.8 mW in the same manner as in Example 11, and
After that, when this optical disc was played back on the same CD player as in Example 11, the reflectance of the semiconductor laser was 71%.
,Iz/1,. , is 0. 64, Is/It. , is 0.32) Block error rate BLER is 2.8X1
It was 0".

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 17) In the above Example 11, the silicon acrylic resin layer is not provided and the reflective layer 3 is made of iridium and gold.
9 was formed by sputtering, and on the light reflective layer, a 20 nm thick binding layer of polyisoprene was formed by spin coating 1-L, and on top of this was formed an ultraviolet curable resin. An optical disc was manufactured in the same manner as in Example 11 above, except that the protective layer 4 made of A.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.4 mW in the same manner as in Example 11, and
After that, when this optical disc was played back on the same CD player as in Example 11, the reflectance of the semiconductor laser was 72%.
, I++/1,. , is 0.64.1s/It-e is 0.
32) Block error rate BLER is 4. 1X10
-31? there were.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 18) In Example 11, the silicon acrylic resin layer was not provided, a copper film with a thickness of 50% m was formed as the reflective layer 3, and bisphenol diluted in diglycidyl ether solvent was used as the protective layer 4. An optical disc was manufactured in the same manner as in Example 11 above, except that a 5 μm thick epoxy resin layer was formed by spin-coding the curable epoxy resin. The above protective layer has a Rockwell hardness of AS.
TM D785 is M! 10, it functions as a hard layer.

EFM signals were recorded on the optical disk thus obtained at a recording power of 7.0 mW in the same manner as in Example 11, and then this optical disk was played back using the same CD player as in Example 11. The reflectance of
%,I+,/1,. , is 0.64. Ia/I*. , is 0
．． 33. Block error rate BLER is 2.9X10
-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 19) In Example II above, a silicate layer with a thickness of 0.01 μm was provided on the resin layer by spin-firing a silicone coating agent, and a light absorption layer 2 was formed on the silicate layer. ,
No silicon acrylic resin layer was provided, a copper film with a thickness of 50% m was formed as the reflective layer 3, and the protective layer 4
A bisphenol-curing epoxy resin diluted with diglycidyl ether solvent was spin-coded to a thickness of 5 μm.
Example 1 above except that an epoxy resin layer was formed.
An optical disc was manufactured in the same manner as in 1.

An optical disc obtained in this way? When an EFM signal was recorded at a recording power of 7.0 mW in the same manner as in Example 11, and this optical disc was then played back using the same CD player as in Example 11, the reflectance of the semiconductor laser was 74.
%, I++/1,. , is 0.64. Summer 3/I. , is 0
．． 33, block error rate) BLER is 3.5XIO
-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate 10 of the optical disc after recording was coated with STMC5cannig Tu.
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 20) In Example 11 above, a foaming agent was mixed into the acrylic resin, no silicone acrylic resin layer was provided, and a copper film with a thickness of 50% m was formed by vacuum evaporation as the reflective layer 3. 8 of toluene and methyl ethyl ketone on top of the reflective layer.
: The protective layer 4 was formed via a 20% m thick binding layer formed by spin-coding polyvinyl acetate resin dissolved in the solvent of 4, and bisphenol diluted with diglycidyl ether solvent as the protective layer 4. Epoxy tree JJIltJ with a thickness of 58m made by spin-coding hardened evo-gyushi resin
An optical disc was manufactured in the same manner as in Example 11 above, except for forming m.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.4 mW in the same manner as in Example 11, and
Thereafter, when this optical disc was played back on the same CD player as in Example 11, the reflectance of the semiconductor laser was 74%.
, I++/1,. , is 0.64, Is/I*- is 0.3
3. The block error rate BLER was 3.6XIO''.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 21) A spiral-shaped pregroove 8 having a width of 0.8 μm, a depth of 0.08 μm, and a pitch of 1.6 μm was formed on the surface with a thickness of 1. 2mm5 Outer diameter 120mmφ, Inner diameter 1
On a glass substrate 1 with a diameter of 6 mm, 0.5 g of 1.1' dipropyl and 3. 3. 3'31 Tetramethyl 6.5' Diethoxyindodicarpocyanine verchlorate was dissolved in 10 cc of dichloroethane solvent, and this was added to the above substrate 1.
was coated on the surface of
nm optical absorption J152 was formed.

Next, a reflective layer 3 was formed by depositing an Au film with a thickness of 50 nm on the entire surface of the disk with a diameter of 45 to 118 mm by sputtering. Furthermore, this reflective layer 3
Add 1 urethane resin dissolved in methyl ethyl ketone on top.
This was spin-coded to a thickness of 100 nm to form a buffer layer, and an ultraviolet curable resin was spin-coded thereon and cured by irradiating ultraviolet rays to form a protective layer 4 with a thickness of 10 μm.

A semiconductor laser with a wavelength of 780 nm was applied to the optical disc thus obtained at a linear velocity of 1.2 m/5ecs and a recording power of 7.2 m.
It was irradiated with W and the EFM signal was recorded. Thereafter, this optical disc is inserted into a commercially available CD player (Aurex
When reproducing with V73 (wavelength of reproducing light λ = 780 nm), the reflectance of the semiconductor laser was 77%, I , , / I
T.

was 0.65.1s/1*, -0.33, block error rate) BLER was 3.0X10-3.

In addition, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 22) A spiral pregroove 8 having a width of 0°8 μm1, a depth of 0.08 μm1, and a pitch of 1.6 μm was formed on the surface with a thickness of 1.6 μm. 2mm5 Outer diameter 120mmφ, Inner diameter 1
A polycarbonate substrate 1 with a diameter of 5 mm was injection molded. As an organic dye for forming light-absorbing Jifi2, 0.
5gL:J)l, I', dipropyl3. 3
．． 3', 3' Tetramethyl 5.51 diethoxyindodicarpocyanine perchlorate was dissolved in 10 cC of isopropyl alcohol solvent, and this was applied to the surface of the above substrate 1 by a spin code method, so that one sample had a thickness of 11
A light absorption layer 2 of 00n was formed. Furthermore, 5iO on top of this
eWX was deposited to a thickness of 40% m by sputtering.

Next, a 50 nm thick layer of Au 11 was deposited on the entire surface of the disk with a diameter of 45 to 118 mmφ using a sputtering method.
A film was formed to form a reflective layer 3. Furthermore, a urethane resin dissolved in methyl ethyl ketone was spin-coded onto the reflective layer 3 to a thickness of 1100 nm to form a buffer layer.
On top of this, an ultraviolet curable resin was spin-coated and cured by irradiating ultraviolet rays to form a protective layer 4 with a thickness of 10 μm.

A semiconductor laser with a wavelength of 780 nm was applied to the optical disc thus obtained at a linear velocity of 1.2 m/5ect and a recording power of 6.8 m.
It was irradiated with W and the EFM signal was recorded. Thereafter, this optical disc is inserted into a commercially available CD player (Aurex
When reproducing with V73 (reproduction light wavelength λ = 780 nm), the reflectance of the semiconductor laser was 77%, I + + / l
to- was 0.66, Ia/L0- was 0.36, and block error rate BLER was 3.5×10-'.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 2 was confirmed.

(Example 23) Same as Example 22 above, except that 5iO2111 was formed by the LPD method and dioxane solvent was used as a solvent for the coating agent when forming the light absorption layer 2. and produced an optical disc.

EFM signals were recorded on the thus obtained optical disc at a recording power of 7.2 mW in the same manner as in Example 22, and then this optical disc was played back using the same CD player as in Example 22. The reflectance of
%, I++/1,. , is 0.66, Is/I*. , is 0
．． 35. Block error rate BLER is 4.0XIO
-” was.

Further, in the same manner as in Example 1, the surface of the transparent substrate 10 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 24) In the above Example 22, instead of the SiO2 film, an epoxy resin dissolved in diglycidyl ether was spin-coded to form an epoxy resin layer with a thickness of 1100 nm, and the reflective layer 3 was made of gold and titanium. 9: 1 m of alloy thin film was formed at a ratio of 1, and a light absorbing layer 2 and a reflective layer of 1 m were formed.
An optical disc was manufactured in the same manner as in Example 22, except that a polybutadiene resin layer dissolved in cyclohexane was spin-coded to form a polybutadiene resin layer with a thickness of 120% m between the disc and the disc.

EFM signals were recorded on the thus obtained optical disk at a recording power of 7.0 mW in the same manner as in Example 22, and then this optical disk was played back using the same CD player as in Example 22. The reflectance of
%, I++/11°, is 0.84, Is/Ir. , is 0
．． 33, block error rate) BLER is 2.5X10
-3.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope, the same condition as in Example 1 was confirmed.

(Example 25) In the above Example 22, 5iOall! Instead, an epoxy resin layer dissolved in diglycidyl ether was spin-coded to form an epoxy resin layer with a thickness of 1100 nm, and an alloy thin film layer of gold and titanium in a ratio of 9:1 was formed as the reflective layer 3. In particular, a polybutadiene resin layer with a thickness of 120% m was provided between the light absorption layer 2 and the reflective layer 3 by spin-coding polybutadiene resin dissolved in cyclohexane, and the difference between the light reflective layer and the protective layer 4 was Except that a bisphenol-curing epoxy resin was spin-coded to a thickness of 20% in order to improve binding.
An optical disc was produced in the same manner as in Example 22 described in Section 2.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.2 mW in the same manner as in Example 22, and
After that, when this optical disc was played back on the same CD player as in Example 22, the reflectance of the semiconductor laser was 74%.
,Ith/1,. , is 0.64, Is/Itop is 0.3
3. Block error rate) BLER was 3.0X10 bow.

Further, in the same manner as in Example 1, the surface of the transparent substrate 1 of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 26) In the above Example 22, instead of 5i0211N, an epoxy resin dissolved in diglycidyl ether was spin-coded to form an epoxy resin layer with a thickness of 1100 nm, and this epoxy resin layer and the reflective layer 3 Example 22 except that a polybutadiene resin layer dissolved in cyclohexane was spin-coded to form a polybutadiene resin layer with a thickness of 120% m and the thickness of the protective layer was 5 μm. An optical disc was produced in the same manner.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.2 mW in the same manner as in Example 22, and
After that, when this optical disc was played back on the same CD player as in Example 22, the reflectance of the semiconductor laser was 74%.
,I,,/1,. , is 0.64, Is/h0- is 0.3
2) Block error rate BLER is 3.3X10-3
Met.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 27) In the above Example 22, 5iO211+ was not formed, and a polybutadiene resin dissolved in cyclohexane was spin-coded between the light absorption layer 2 and the reflection layer 3, and a polybutadiene resin layer with a thickness of 120% m was formed. In order to improve the binding between the reflective layer and the protective layer 4, bisphenol curing epoxy resin was spin-coded to a thickness of 20% m between the reflective layer and the protective layer 4, and the thickness of the protective layer was 5 μm. Except for this, an optical disc was manufactured in the same manner as in Example 22 above.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.2 mW in the same manner as in Example 22, and
After that, when this optical disc was played back on the same CD player as in Example 22, the reflectance of the semiconductor laser was 74%.
,1.1/1,. , is 0.63.1. /1. . , is 0.
32) Block error rate BLER is 2.8XIO-
It was 3.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

(Example 28) An optical disc was manufactured in the same manner as in Example 22 above, except that the SiO2 film was not formed.

An EFM signal was recorded on the optical disc thus obtained at a recording power of 7.2 mW in the same manner as in Example 22, and
After that, when this optical disc was played back on the same CD player as in Example 22, the reflectance of the semiconductor laser was 77%.
,+,,/1,. , is 0.66, I3/It. , is 0.
35, Block error rate BLER is 1.0XIO-
It was 2.

Further, in the same manner as in Example 1, the surface of the transparent substrate l of the optical disc after recording was subjected to STM (Scanning Tube).
When observed using a 300 mm ring microscope), the same condition as in Example 1 was confirmed.

[Effects of the Invention As explained above, according to the optical information recording medium of the present invention,
It is possible to form pits from which a reproduced signal with a high degree of modulation can be obtained.

This has the effect that an optical information recording medium compatible with the CD format can be easily obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic half-sectional perspective view showing an example of R4W of an optical information recording medium, and FIG. 2 is a partial enlarged view of the optical information recording medium in FIG. 3 is a partially enlarged cross-sectional view of the optical information recording medium of FIG. 1 taken along the track after optical recording, and FIGS. 4 to 7 are cross-sectional views taken along the track to show each side of the optical information recording medium bit. FIG. 8 is an enlarged perspective view of the main part showing the surface of the transparent substrate of the optical information recording medium after recording, and FIG. TM (Scannig T
This is an example of a graph showing the relationship between the moving distance of the chip along the tracking direction and the altitude when observed with a rolling microscope. l...Substrate 2...Light absorption layer 3...Light reflection layer
4... Protective layer 5... Beep) 8.6'... Deformed part 10.10'... Void part 11... Fine air bubbles 12.13... Optical property modified part

Claims (9)

[Claims] (1) A light absorption layer that absorbs laser light directly or through another layer on a transparent substrate, and a light reflection layer that reflects laser light directly on the light absorption layer or through another layer. An optical information recording medium in which a layer and pits for reproducing data are formed by irradiation with laser light, characterized in that a layer on the substrate side adjacent to the light absorption layer in the pit portion is deformed. optical information recording medium. (2) The optical information recording medium according to claim 1, wherein the deformation of the layer on the substrate side adjacent to the light absorption layer is a convex deformation toward the light absorption layer side. (3) The optical information recording medium according to claim 1, wherein the deformation of the layer on the substrate side adjacent to the light absorption layer is a concave deformation toward the light absorption layer side. (4) The optical information recording medium according to claim 1, wherein the layer on the substrate side adjacent to the light absorption layer is deformed in a wave-like manner. (5) In any one of claims 1 to 4, a layer on the substrate side adjacent to the light absorption layer in the pit portion has an optical property modified portion where the optical properties are locally changed. Optical information recording medium. (6) Optical information recording according to any of claims 1 to 5, in which voids are formed at the interface between the light absorption layer in the pit portion and another layer adjacent to the same layer. Medium. (7) An optical information recording medium according to any one of claims 1 to 6, in which fine air bubbles are dispersed in the light absorption layer in the pit portion. (8) A light absorption layer that absorbs laser light directly or through another layer on the transparent substrate, and a light reflection layer that reflects the laser light directly on the light absorption layer or through another layer. In an optical information recording medium in which pits are formed for reproducing data by irradiation with a laser beam, the optical properties of the layer on the substrate side adjacent to the light absorption layer in the pit area are locally changed. An optical information recording medium characterized by having an optical property modification portion. (9) The optical information recording medium according to claim 8, wherein the optical property modification portion is formed by diffusing decomposed components of the light absorption layer into a layer on the substrate side adjacent to the light absorption layer.