Optical resin wafer manufacturing method

Abstract

The purpose of the present invention is to provide an optical resin wafer manufacturing method which can obtain an optical resin wafer having an improved flatness property. An optical resin wafer having an improved flatness property can be obtained by said optical resin wafer manufacturing method comprising: a mold preparation step for preparing a mold that satisfies the following (a) or (b); and a curing step for obtaining an optical resin wafer precursor by casting and curing a curable composition serving as a raw material for the wafer in the mold.　(a) The mold has one or more spacers in the center of a cavity space.　(b) The relationship between the thickness tm0 at the center of the cavity space of the mold and the thickness tm1 at a position 5 mm from the outer circumference toward the center of the cavity space of the mold satisfies tm0>tm1.

Description

Optical resin wafer manufacturing method

[0001] The present invention relates to a method for manufacturing an optical resin wafer.

[0002] In the field of optical devices, there is a demand for resin materials due to reasons such as light weight and improved impact resistance.

[0003] Patent Document 1 describes a method for producing a thin film containing an organic polymer and having an area of ​​1 mm ２ or more, and the area is 1 mm ２ The patent document 1 also describes that "an object of the present disclosure is to provide an optical member that is lightweight and capable of transmitting optical information with high precision, a method for manufacturing the same, and an optical information transmission device that includes the optical member."

[0004] International Publication No. 2020 / 170801

[0005] A known method for manufacturing optical components from resin materials is to cast the resin material into a mold, but molding using a mold can result in poor flatness of the optical resin wafer due to factors such as shrinkage during hardening of the resin material.

[0006] The present invention provides a method for manufacturing an optical resin wafer, which can provide an optical resin wafer with improved flatness.

[0007] According to the present invention, there is provided a method for manufacturing an optical resin wafer as follows.

[0008] 1. A method for manufacturing an optical resin wafer, comprising: a mold preparation step of preparing a mold that satisfies the following (a) or (b), and a curing step of casting a curable composition that is a raw material for the optical resin wafer into the mold and curing it to obtain an optical resin wafer precursor. (a) The mold has one or more spacers in the center of the cavity space. (b) The thickness t of the center of the cavity space of the mold ｍ０ and the thickness t at a point 5 mm from the outer periphery toward the center of the cavity space of the mold. ｍ１ The relationship betweenｍ０ >t ｍ１ 2. The method for producing an optical resin wafer according to 1., further comprising a processing step of performing at least one processing selected from the group consisting of notching, burring, beveling, cutting, grinding, polishing, and heating on the optical resin wafer precursor to obtain an optical resin wafer. 3. The method for producing an optical resin wafer according to 1. or 2., wherein the mold satisfies (a) above and has one or more spacers within a range of 25 mm from the edge of the cavity space toward the center. 4. The method for producing an optical resin wafer according to 3., wherein the mold satisfies (a) above, and the spacers are arranged so as to occupy 80% or more of the outer periphery of the cavity space. 5. The method for producing an optical resin wafer according to any of 1. to 4., wherein the mold satisfies (a) above, and the shape of the spacers is a circular column, a polygonal column, a cylinder, or a square tube. 6. A method for producing an optical resin wafer according to any one of 1. to 5., wherein the mold satisfies (a), and the spacer has a structure that allows the curable composition to be poured into the cavity. 7. A method for producing an optical resin wafer according to any one of 1. to 6., wherein the mold satisfies (a), and the spacer comprises at least one selected from the group consisting of glass, ceramic, metal, and resin. 8. A method for producing an optical resin wafer according to any one of 1. to 7., wherein the mold comprises glass. 9. A method for producing an optical resin wafer according to 1. to 8., wherein the optical resin wafer comprises at least one selected from the group consisting of (thio)urethane-based optical resins, epoxy-based optical resins, polycarbonate-based optical resins, episulfide-based optical resins, allyl carbonate-based optical resins, nylon-based optical resins, polyamide-based optical resins, and polyimide-based optical resins. 10. A method for producing an optical resin wafer according to 1. to 9., wherein the refractive index of the optical resin wafer is 1.47 or more. 11. The method for producing an optical resin wafer according to any one of 1. to 10., wherein the cure shrinkage rate A of the curable composition calculated by the following formula (x) is 15% or less: A=(V ０ -V １ ) / V ０× 100 A: Curing shrinkage rate [%] V ０ : Volume of the curable composition (before curing) V １ : Volume of the optical resin wafer precursor (after curing) 12. A method for manufacturing an optical resin wafer according to any one of 1. to 11., wherein the average thickness of the optical resin wafer is 0.1 mm to 3.0 mm. 13. A method for manufacturing an optical resin wafer according to any one of 1. to 12., wherein the diameter of the optical resin wafer is 50 mm to 350 mm. 14. A method for manufacturing an optical resin wafer according to any one of 1. to 13., wherein the flatness of the optical resin wafer is 350 μm or less.

[0009] According to the present invention, it is possible to provide a manufacturing method of an optical resin wafer that can obtain an optical resin wafer with improved flatness.

[0010] 1A and 1B are a cross-sectional view (1A) and a top view (1B) schematically showing an example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 1. FIG. 2A and a top view (2B) are a cross-sectional view (3A) and a top view (3B) schematically showing an example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 1. FIG. 4A and a top view (4B) are a cross-sectional view (4A) and a top view (4B) schematically showing an example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 1. FIG. 2B are a cross-sectional view (4A) and a top view (4B) schematically showing an example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 2. FIG. 3A are a cross-sectional view (4A) and a top view (4B) schematically showing an example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 2. FIG. 3B are a cross-sectional view (4A) and a top view (4B) schematically showing an example of an optical resin wafer obtained by the manufacturing method of the optical resin wafer of this embodiment 2. FIG. 4A are a cross-sectional view (4A) and a top view (4B) schematically showing an example of an optical resin wafer obtained by the manufacturing method of the optical resin wafer of this embodiment 2. FIG. 4B ...

[0011] Hereinafter, an embodiment of the present invention will be described.

[0012] 1. Manufacturing method of optical resin wafer The manufacturing method of the optical resin wafer of this embodiment includes a mold preparation step of preparing a mold that satisfies the following (a) or (b), and a curing step of casting a curable composition that is a raw material of the optical resin wafer of this embodiment into the mold of this embodiment and curing it to obtain an optical resin wafer precursor. (a) The mold of this embodiment has one or more spacers in the center of the cavity space. (b) The thickness t of the center of the cavity space of the mold of this embodiment ｍ０ and the thickness t at a point 5 mm from the outer periphery toward the center of the cavity space of the mold of this embodiment. ｍ１ The relationship between ｍ０ >t ｍ１ This becomes:

[0013] Hereinafter, a method for manufacturing an optical resin wafer will be described with reference to a first embodiment and a second embodiment.

[0014] 1-1. Embodiment 1 Figure 1 is a cross-sectional view (Figure 1A) and a top view (Figure 1B) schematically showing an example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 1. The manufacturing method of the optical resin wafer of this embodiment 1 (hereinafter may be abbreviated as "present embodiment 1") includes a mold preparation process (hereinafter may be abbreviated as "mold preparation process") for preparing a mold 51 that satisfies the following (a), and a curing process (hereinafter may be abbreviated as "curing process") for casting a curable composition that is a raw material for the optical resin wafer into the mold 51 and curing it to obtain an optical resin wafer precursor. (a) The mold 51 has one or more spacers in the center of the cavity space.

[0015] The mold 51 is, for example, a glass mold, and has a cylindrical cavity space 52. Furthermore, for example, one cylindrical glass spacer 54 is disposed in a central portion 53 of the cavity space 52.

[0016] The present inventors have confirmed that when a curable composition serving as a raw material for an optical resin wafer is cast-molded, cure shrinkage occurs, causing a depression in the center of the cured product, making it difficult to ensure the flatness of the resulting optical resin wafer. Furthermore, the present inventors have discovered that by placing one or more spacers in the center of the mold cavity, the depression in the center of the cured product can be suppressed, making it easier to ensure the flatness of the optical resin wafer. The depression in the center of the cured product is thought to be caused by the composition being drawn to the center due to cure shrinkage, and the presence of a spacer in the center is thought to suppress this.

[0017] In the first embodiment, the spacer 54 is placed in the cavity space 52, and the mold 51 is prepared for use in the curing step. Note that the mold preparation step can be considered as being prepared even if no specific work has been performed, as long as the mold is ready for use in the curing step.

[0018] The prepared mold 51 is provided with, for example, a resin pouring passage (not shown), and a curable composition containing an isocyanate compound, a polythiol compound, etc., which is the raw material for the optical resin wafer, is poured through the resin pouring passage. Then, for example, the curable composition is thermally cured by heating, and an optical resin wafer precursor made of a (thio)urethane-based optical resin is taken out of the mold.

[0019] The obtained optical resin wafer precursor is subjected to, for example, burr processing to remove burrs remaining on the outer periphery, and notch processing to form a notch at the end of the optical resin wafer precursor, thereby obtaining an optical resin wafer made of a (thio)urethane-based optical resin.

[0020] In this embodiment 1, the mold 51 preferably has one or more spacers within a range of 25 mm from the end 55 of the cavity space 52 toward the center 53. By using such a mold, it becomes easier to ensure the flatness of the optical resin wafer. Note that the spacers 54 arranged within a range of 25 mm from the end of the cavity space toward the center can also be used to form a notch, and the obtained notch can function as a mark to indicate the orientation of the optical resin wafer.

[0021] FIG. 2 is a cross-sectional view ( FIG. 2A ) and a top view ( FIG. 2B ) schematically illustrating another example of a mold used in the first embodiment. In FIG. 2 , the mold 51 has one spacer 54 arranged in the center 53 of the cavity space 52, and one spacer 54 arranged within a range of 25 mm from the edge 55 of the cavity space 52 toward the center 53. The mold of the first embodiment may have spacers arranged in this manner. By using such a mold, it becomes easier to ensure the flatness of the optical resin wafer. The spacer 54 arranged within a range of 25 mm from the edge of the cavity space toward the center can also be used to form a notch, and the resulting notch can function as a mark for indicating the orientation of the optical resin wafer.

[0022] FIG. 3 is a cross-sectional view ( FIG. 3A ) and a top view ( FIG. 3B ) schematically illustrating another example of a mold used in the first embodiment. In FIG. 3 , the mold 51 has one spacer 54 disposed in the center 53 of the cavity space 52, and two spacers 54 disposed symmetrically around the center 53 within a range of 25 mm from the end 55 of the cavity space 52 toward the center 53. The mold of the first embodiment may have spacers disposed in this manner. The mold of the first embodiment may preferably have two or more spacers, more preferably four or more spacers, even more preferably six or more spacers, and particularly preferably eight or more spacers. Using such a mold makes it easier to ensure the flatness of the optical resin wafer.

[0023] The spacer 54 (preferably the spacer 54 at the end 55 of the cavity space) may have a structure that allows the curable composition to be poured into the cavity space 52. This allows the spacer to also serve as a resin pouring passage, eliminating the need to provide a separate resin pouring passage and making it easier to reduce manufacturing costs.

[0024] FIG. 4 is a cross-sectional view ( FIG. 4A ) and a top view ( FIG. 4B ) schematically illustrating another example of a mold used in the first embodiment. In FIG. 4 , the mold 51 has one spacer 54 arranged in the center 53 of the cavity space 52, and cylindrical (annular in plan view) spacers 54 arranged so as to occupy 80% or more of the outer periphery of the cavity space 52. The mold of the first embodiment may have spacers arranged in this manner. The mold of the first embodiment may preferably have spacers occupying 85% or more of the outer periphery, and more preferably have spacers occupying 90% or more of the outer periphery. Using such a mold makes it easier to ensure the flatness of the optical resin wafer. Note that the outer periphery of the mold in this embodiment refers to the range within 25 mm from the end 5 toward the center 53 of the cavity space 52 of the mold 51.

[0025] The shape of the spacer used in this embodiment 1 may be, for example, a columnar shape, a polygonal columnar shape, a cylindrical shape, or a square tube shape. From the viewpoint of easy demolding, a columnar shape is preferable. Note that the spacer 54 located at the end 55 of the cavity space of the mold 51 in FIG. 4 has a cylindrical shape (annular shape in top view).

[0026] The material of the mold used in the first embodiment is not particularly limited, but the linear expansion coefficient a ｍ is preferably 0.1 × 10 －６ / °C or more, more preferably 0.5 × 10 －６ / °C or more, more preferably 1 × 10 －６ / °C or more, more preferably 2 × 10 －６ / °C or more, more preferably 3 x 10 －６ / °C or more, and preferably 100 x 10－６ / °C or less, more preferably 50 x 10 －６ / °C or less, more preferably 40 x 10 －６ / °C or less, more preferably 30 x 10 －６ / °C or less, more preferably 20 x 10 －６ / °C or less, more preferably 15 x 10 －６ / °C or less. This makes it possible to further improve the flatness of the optical resin wafer. ｍ was measured in accordance with Japanese Industrial Standard JIS K-7197:2012 under the condition of a temperature rise rate of 5°C / min from 25°C to 150°C.

[0027] The mold material used in this embodiment has a linear expansion coefficient a ｍ From the viewpoint of setting the range of the thickness of the sintered body to an appropriate range, for example, metal materials such as SUS, copper, silver, iron, etc. (9 to 20 × 10 －６ / °C), glass materials such as white plate glass and blue plate glass (9 to 20 × 10 －６ / °C), inorganic materials such as borosilicate glass, alumina, and single crystal sapphire (3 to 8 × 10 －６ / ℃), quartz (0.5×10 －６ / °C), preferably metal, glass, or an inorganic material, more preferably glass.

[0028] The material of the spacer used in the first embodiment is not particularly limited, but the linear expansion coefficient a ｓ is preferably 0.1 × 10 －６ / °C or more, more preferably 0.5 × 10 －６ / °C or more, more preferably 1 × 10 －６ / °C or more, more preferably 2 × 10 －６ / °C or more, more preferably 3 x 10 －６ / °C or more, and preferably 500 x 10 －６ / °C or less, more preferably 400 × 10 －６ / °C or less, more preferably 200 x 10 －６ / °C or less, more preferably 80 x 10 －６ / °C or less, more preferably 65 x 10 －６ / °C or less, more preferably 20 x 10 －６ / °C or less. This makes it possible to further improve the flatness of the optical resin wafer. ｓ was measured in accordance with JIS K-7197:2012 under the condition of a temperature rise rate of 5°C / min from 25°C to 150°C.

[0029] The spacer of this embodiment is made of a material having a linear expansion coefficient a ｓ From the viewpoint of setting the range of the thickness of the elastomer to an appropriate range, for example, elastomers such as silicone, styrene, chloroprene, and nitrile (60 to 400 × 10 －６ / ℃), LDPE (100-400×10 －６ / ℃), polycarbonate, PET, nylon and other engineering plastic materials (50-80 × 10 －６ / °C), metal materials such as SUS, copper, silver, and iron (9 to 20 × 10 －６ / ℃), white plate glass, blue plate glass, etc. (9 to 20 × 10 －６ / °C), inorganic materials such as borosilicate glass, alumina, and single crystal sapphire (3 to 8 × 10 －６ / ℃), quartz (0.5×10 －６ / °C), and metal, glass, and inorganic materials are preferred.

[0030] In addition, the spacer of this embodiment is made of a material having a linear expansion coefficient a ｓ In terms of setting the range of the thickness of the spacer to an appropriate range and the ease of processing the spacer, the spacer preferably contains at least one material selected from the group consisting of glass, ceramic, metal, and resin, and particularly preferably contains glass.

[0031] From the viewpoint of improving optical properties, the material of the optical resin wafer produced in this embodiment 1 preferably contains at least one selected from the group consisting of (thio)urethane-based optical resins, epoxy-based optical resins, polycarbonate-based optical resins, episulfide-based optical resins, allyl carbonate-based optical resins (preferably diallyl carbonate-based optical resins), nylon-based optical resins, polyamide-based optical resins, and polyimide-based optical resins, more preferably contains a (thio)urethane-based optical resin, and particularly preferably contains a thiourethane resin.

[0032] The components of the curable composition used in this embodiment 1 are appropriately selected depending on the material of the target optical resin wafer. When the material of the target optical resin wafer is a (thio)urethane-based optical resin, the curable composition can be obtained by polycondensing an iso(thio)cyanate compound and a bifunctional or higher active hydrogen compound (for example, a polythiol compound, a polyol compound, etc.).

[0033] Examples of the iso(thio)cyanate compound used in the curable composition of the first embodiment include hexamethylene diisocyanate, pentamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, bis(isocyanatomethyl)cyclohexane, bis(isocyanatocyclohexyl)methane, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, tolylene diisocyanate, phenylene diisocyanate, and 4,4'-diphenylmethane diisocyanate.

[0034] Examples of the polythiol compound used in the curable composition of the first embodiment include pentaerythritol tetrakis(2-mercaptoacetate), pentaerythritol tetrakis(3-mercaptopropionate), bis(2-mercaptoethyl) sulfide, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto mercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 2,5-dimercaptomethyl-1,4-dithiane, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane, 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane, ethylene glycol bis(3-mercaptopropionate), and the like.

[0035] Examples of the polyol compound used in the curable composition of the first embodiment include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,5-pentanediol, 2,4-pentanediol, and 2-methyl-2,4-pentanediol. linear or branched aliphatic alcohols such as 1,2-cyclopentanediol, 1,3-cyclopentanediol, 3-methyl-1,2-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 4,4'-bicyclohexanol, and 1,4-cyclohexanedimethanol; and the like.

[0036] The curing conditions in the curing step of this embodiment 1 should be appropriately selected depending on the material of the target optical resin wafer, but from the viewpoint of suppressing thermal runaway and convection due to reaction heat, the curing temperature is, when the glass transition temperature (Tg) of the optical resin that is the raw material of the optical resin wafer is used as the reference, preferably glass transition temperature (Tg) + 10°C or more, more preferably glass transition temperature (Tg) + 15°C or more, even more preferably glass transition temperature (Tg) + 20°C or more, and preferably glass transition temperature (Tg) + 40°C or less, more preferably glass transition temperature (Tg) + 35°C or less, and even more preferably glass transition temperature (Tg) + 30°C or less. In addition, a specific curing temperature is usually 110°C to 140°C.

[0037] The temperature rise time in the curing step of the present embodiment 1 is preferably 1 hour or longer, more preferably 1.1 hours or longer, even more preferably 1.2 hours or longer, even more preferably 1.8 hours or longer, even more preferably 1.9 hours or longer, and even more preferably 2 hours or longer, from the viewpoint of suppressing thermal runaway and convection due to the heat of reaction. When the amount of optical resin is large, the temperature rise time may be 12 hours or longer, 14 hours or longer, 16 hours or longer, 20 hours or longer, 22 hours or longer, or 24 hours or longer. When the amount of optical resin is even larger, the temperature rise time may be 24 hours or longer, 26 hours or longer, 28 hours or longer, 44 hours or longer, 46 hours or longer, or 48 hours or longer.

[0038] The curing temperature holding time in the curing step of the present embodiment 1 is preferably 1 hour or longer, more preferably 1.1 hours or longer, even more preferably 1.2 hours or longer, even more preferably 1.8 hours or longer, even more preferably 1.9 hours or longer, and even more preferably 2 hours or longer, from the viewpoint of suppressing thermal runaway and convection due to the heat of reaction.

[0039] In order to reduce unreacted materials, the temperature-lowering time in the curing step of the present embodiment 1 is preferably 1 hour or longer, more preferably 1.1 hours or longer, even more preferably 1.2 hours or longer, even more preferably 1.8 hours or longer, even more preferably 1.9 hours or longer, and even more preferably 2 hours or longer. When the amount of optical resin is large, the temperature-lowering time may be 12 hours or longer, 14 hours or longer, 16 hours or longer, 20 hours or longer, 22 hours or longer, or 24 hours or longer. When the amount of optical resin is even larger, the temperature-lowering time may be 24 hours or longer, 26 hours or longer, 28 hours or longer, 44 hours or longer, 46 hours or longer, or 48 hours or longer.

[0040] This embodiment 1 preferably includes a processing step of performing at least one process selected from the group consisting of notch processing, burr processing, beveling processing, cutting processing, grinding processing, polishing processing, and heating processing on the optical resin wafer precursor to obtain an optical resin wafer.

[0041] Notch processing is a process for forming a notch, which serves as a mark for indicating the orientation of an optical resin wafer. The equipment and conditions used for notch processing are not particularly limited, and known equipment and conditions can be appropriately adopted for processing.

[0042] Deburring is a process of removing burrs such as protrusions that occur on the outer periphery of the optical resin wafer precursor. The equipment and conditions used for deburring are not particularly limited, and known equipment and conditions can be appropriately adopted for processing.

[0043] Beveling is a process of cutting off the corners of the outer periphery of the optical resin wafer precursor and rounding (chamfering) it in the thickness direction. The apparatus and conditions used for beveling are not particularly limited, and known apparatuses and conditions can be appropriately adopted for processing.

[0044] The cutting process is a process of cutting the optical resin wafer precursor to obtain an optical resin wafer of a desired thickness. The device and conditions used for the cutting process are not particularly limited, and known devices such as a wire saw and a blade saw can be used appropriately.

[0045] Grinding is a process of grinding the surface of the optical resin wafer precursor to ensure flatness, etc. Polishing is a process of polishing the surface of the optical resin wafer precursor to ensure flatness, etc. The methods and conditions of the grinding and polishing processes are not particularly limited, and for example, the methods described in paragraphs

[0047] to

[0062] of WO 2020 / 170801 can be appropriately adopted.

[0046] Heat processing is a process of heating a cured product for the purpose of alleviating internal stress of the optical resin wafer precursor. Heating activates the movement of the molecules that make up the optical resin wafer precursor, removing distortion in the optical resin wafer precursor, and thereby flattening the optical resin wafer. The heating temperature in the heat processing is preferably 60°C or higher, more preferably 70°C or higher, even more preferably 80°C or higher, even more preferably 90°C or higher, and even more preferably 100°C or higher, from the viewpoint of further flattening the optical resin wafer. Furthermore, based on the glass transition temperature (Tg) of the optical resin that is the raw material for the optical resin wafer, the temperature is preferably Tg-20°C or higher, more preferably Tg-10°C or higher, even more preferably Tg or higher, even more preferably Tg+10°C or higher, even more preferably Tg+20°C or higher, even more preferably Tg+30°C or higher, even more preferably Tg+40°C or higher, and even more preferably Tg+50°C or higher. If the thermal degradation of the optical resin wafer is within an acceptable range, the temperature may be, for example, 200°C or lower. In addition, when determining the heating processing temperature, it is advisable to refer to the temperature dependence of the storage modulus and loss modulus by viscoelasticity measurement. In addition, in the heating processing, from the viewpoint of further suppressing warpage, pressure may be further applied. Specifically, pressure may be applied by sandwiching the optical resin wafer of this embodiment between flat plates and pressing.

[0047] The average thickness of the optical resin wafer produced in this embodiment 1 can be adjusted appropriately according to the use of the optical resin wafer, but is preferably 0.1 mm or more, more preferably 0.2 mm or more, even more preferably 0.3 mm or more, and is preferably 3.0 mm or less, more preferably 2.0 mm or less, even more preferably 1.0 mm or less. Note that the average thickness of the optical resin wafer produced in this embodiment 1 is the arithmetic mean of the thickness at a point 5 mm from the edge of the hole of the optical resin wafer toward the outer periphery and the thickness at a point 5 mm from the outer periphery toward the center of the optical resin wafer.

[0048] The diameter of the optical resin wafer manufactured in this embodiment 1 can be adjusted appropriately according to the use of the optical resin wafer, but from the viewpoint of being able to obtain more optical components from one optical resin wafer, it is preferably 50 mm or more, more preferably 70 mm or more, even more preferably 80 mm or more, even more preferably 100 mm or more, even more preferably 120 mm or more, even more preferably 140 mm or more, and may be, for example, 350 mm or less. Here, the larger the diameter of the optical resin wafer, the greater the force that the resin composition is drawn toward the center of the cavity space of the mold due to the curing shrinkage of the resin composition, and the flatness of the optical resin wafer is likely to decrease, but according to this embodiment 1, even if the diameter of the optical resin wafer is above the above lower limit, the flatness can be improved.

[0049] The optical resin wafer manufactured in this embodiment 1 may be required to have improved flatness and smoothness and reduced thickness unevenness because it is used as a material for optical products.In addition, the difference between the maximum and minimum values ​​(PV) of the measurement or WARP may simply be used as an index of reduced thickness unevenness.The preferred ranges of Bow, which is an index of flatness / flatness / planarity required for the optical resin wafer manufactured in this embodiment 1, TTV, which is an index of thickness unevenness, and surface roughness Ra, which is an index of smoothness, are, for example, as follows.

[0050] The flatness / flatness / planarity of the optical resin wafer manufactured in this embodiment 1 is preferably 350 μm or less, more preferably 300 μm or less, even more preferably 250 μm or less, even more preferably 200 μm or less, even more preferably 150 μm or less, even more preferably 100 μm or less, even more preferably 50 μm or less, even more preferably 40 μm or less, even more preferably 30 μm or less, and may be, for example, 0.01 μm or more, 0.1 μm or more, 1 μm or more, or 10 μm or more.

[0051] The flatness / flatness / planarity of the optical resin wafer manufactured in this embodiment 1 refers to the bow of the optical resin wafer, and can be measured using an ultra-high precision three-dimensional measuring machine. For example, it can be measured under the following conditions. In this embodiment 1, bow is the amount that represents the distance from the reference (standard) surface at the center of the wafer when the wafer is held in its natural state without vacuum suction. Apparatus: UA3P (manufactured by Panasonic Production Engineering Co., Ltd.) Measurement area: Circular area of ​​±30 mm in the X and Y directions from the center of the optical resin wafer Alternatively, the difference between the maximum and minimum values ​​of the measurement (PV) or WARP may simply be used as an index.

[0052] The thickness unevenness TTV of the optical resin wafer manufactured in this embodiment 1 is preferably 10 μm or less, more preferably 5 μm or less, even more preferably 2 μm or less, and still more preferably 1 μm or less, and the lower limit of the thickness unevenness TTV is not particularly limited, but may be, for example, 0.01 μm or more, or 0.1 μm or more. In this embodiment, TTV is the difference between the maximum and minimum values ​​of the thickness (distance from the back surface reference plane) when the wafer is fixed by suction.

[0053] The surface roughness Ra of the optical resin wafer manufactured in this embodiment 1 is preferably 10 nm or less, more preferably 5 nm or less, even more preferably 2 nm or less, and even more preferably 1 nm or less, and the lower limit of the surface roughness Ra is not particularly limited, but may be, for example, 0.01 nm or more, or 0.1 nm or more. The surface roughness Ra of the optical resin wafer can be determined by measurement in accordance with Japanese Industrial Standards JIS B 0601:2013.

[0054] The refractive index of the optical resin wafer manufactured in this embodiment 1 is preferably 1.47 or more, more preferably 1.49 or more, even more preferably 1.51 or more, and even more preferably 1.53 or more, from the viewpoint of being able to reduce the thickness of the optical resin wafer while improving the optical properties of the optical resin wafer, and may be, for example, 1.90 or less, for example, 1.80 or less, for example, 1.70 or less. The refractive index of the optical resin wafer can be determined in accordance with Japanese Industrial Standards JIS K-0062:1992, by measurement at a temperature of 25 ° C. and a wavelength of 587.6 nm.

[0055] In the optical resin wafer manufactured in this embodiment 1, from the viewpoint of further flattening the optical resin wafer, the cure shrinkage rate A calculated by the following formula (x) is preferably 15% or less, more preferably 10% or less, and even more preferably 5% or less. The cure shrinkage rate A of the optical resin wafer can be determined by measurement in accordance with Japanese Industrial Standards JIS K-6941-2-4:2014. A=(V ０ -V １ ) / V ０ × 100 (x) A: Curing shrinkage rate [%] V ０ : Volume of the curable composition (before curing) V １ : Volume of optical resin wafer precursor (after curing)

[0056] The linear expansion coefficient a of the optical resin wafer manufactured in this embodiment 1 ｗ is preferably 10 x 10 －６ / °C or more, more preferably 20 x 10 －６ / °C or more, more preferably 30 x 10 －６ / °C or more, more preferably 40 x 10 －６ / °C or more, and preferably 250 x 10 －６ / °C or less, more preferably 200 × 10 －６ / °C or less, more preferably 150 x 10 －６ / °C or less, more preferably 100 x 10 －６ / °C or less, more preferably 80 x 10 －６ / °C or less. This makes it possible to further improve the flatness of the optical resin wafer. ｗ was measured in accordance with JIS K-7197:2012 under the condition of a temperature rise rate of 5°C / min from 25°C to 150°C.

[0057] The optical resin wafer manufactured in this embodiment 1 can be used, for example, in an optical information transmission device. Examples of optical information transmission devices include wearable displays that display virtual reality (VR), augmented reality (AR), etc. When the optical resin wafer manufactured in this embodiment 1 is used in an optical information transmission device, improved flatness and smoothness and reduced thickness unevenness of the optical resin wafer are more required than when used for other purposes. As described above, according to this embodiment 1, it is possible to obtain a wafer with improved flatness and smoothness and reduced thickness unevenness, so the optical resin wafer obtained in this embodiment 1 is suitable for use in an optical information transmission device.

[0058] 1-2. Embodiment 2 Figure 5 is a cross-sectional view showing a schematic example of a mold used in the manufacturing method of the optical resin wafer of this embodiment 2. The manufacturing method of the optical resin wafer of this embodiment 2 (hereinafter, sometimes abbreviated as "present embodiment 2") includes a mold preparation step (hereinafter, sometimes abbreviated as "mold preparation step") of preparing a mold 2 that satisfies the following (b), and a curing step (hereinafter, sometimes abbreviated as "curing step") of casting a curable composition that is a raw material of the optical resin wafer into the mold 2 and curing it to obtain an optical resin wafer precursor. The thickness t of the center of the cavity space ｍ０ is the thickness t at a point 5 mm from the outer periphery toward the center of the cavity space ｍ１ In other words, the molding surface of the mold 2 is a concave surface that is recessed toward the outside of the mold. (b) The thickness tm of the center of the cavity space of the mold 2 is larger than ０ and the thickness tm at a point 5 mm from the outer periphery toward the center of the cavity space of the mold 2. １ The relationship between ｍ０ >tｍ１ This becomes:

[0059] The mold 2 is a mold made of glass and has, for example, a cylindrical cavity space.

[0060] As mentioned above, the present inventors have confirmed that when a curable composition serving as a raw material for an optical resin wafer is cast-molded, cure shrinkage occurs, causing a depression in the center of the cured product, making it difficult to ensure the flatness of the resulting optical resin wafer.The present inventors have then discovered that by making the thickness of the center of the cavity space greater than the thickness at a point 5 mm from the outer periphery toward the center of the cavity space, it is possible to suppress the depression in the center of the cured product and make it easier to ensure the flatness of the optical resin wafer.

[0061] In the second embodiment, a mold 2 is prepared in which the molding surface of the mold is curved so that the thickness of the cavity space increases from the outer periphery toward the center of the cavity space.

[0062] The prepared mold 2 is provided with, for example, a resin pouring passage (not shown), through which a curable composition serving as a raw material for the optical resin wafer is poured. Then, the curable composition is thermally cured by heating, and the optical resin wafer precursor is taken out of the mold.

[0063] The obtained optical resin wafer precursor is subjected to burr processing to remove burrs remaining on the outer periphery, notch processing to form notches at the edge of the optical resin wafer precursor, polishing processing to polish the surface of the optical resin wafer precursor, and heating processing to heat the optical resin wafer precursor, resulting in an optical resin wafer.

[0064] The mold used in this embodiment has a thickness t ｍ０ and the thickness t at a point 5 mm from the outer periphery toward the center of the cavity space ｍ１ However, 0.80X≦t ｍ０ -t ｍ１It is preferable that the relationship of 0.80X≦t≦1.20X is satisfied. Note that X is a value calculated by the following formula (2). The inventors have modeled the amount of deflection that occurs in the optical resin wafer and studied the quantification of the amount of depression that occurs in the center of the optical resin wafer, and have found that this accurately matches X calculated by the following formula (2). Then, in accordance with the material etc. of the target optical resin wafer, it is preferable that the thickness of the center etc. of the mold is set to 0.80X≦t ｍ０ -t ｍ１ It was found that by using a mold that satisfies ≦1.20X, the depressions that occur in the optical resin wafer are offset, making it easier to ensure the flatness of the optical resin wafer.

[0065]

[0066] ν: Poisson's ratio of the mold R: Radius of the cavity space of the mold ρ: Force generated as the curable composition shrinks during cure and exerted on the molding surface of the mold E: Young's modulus of the mold

[0067] In the mold used in this embodiment 2, the thickness t ｍ０ and the thickness t at a point 5 mm from the outer periphery toward the center of the cavity space ｍ１ The relationship is t ｍ０ -t ｍ１ is preferably 0.80X or more, more preferably 0.85X or more, even more preferably 0.90X or more, even more preferably 0.95X or more, and preferably 1.20X or less, more preferably 1.15X or less, even more preferably 1.10X or less, even more preferably 1.05X or less, and preferably 0.80X or more and 1.20X or less, more preferably 0.85X or more and 1.15X or less, even more preferably 0.90X or more and 1.10X or less, even more preferably 0.95X or more and 1.05X or less. This can further improve the flatness of the optical resin wafer.

[0068] The type and dimensions of the curved surface of the molding surface of the mold used in this embodiment 2 are not particularly limited, but for example, the molding surface can be spherical. When the molding surface of the mold used in this embodiment 2 is spherical, the curvature of the growth surface is determined by the thickness t of the central part of the optical resin wafer to be manufactured. ｗ０ The thickness t of the optical resin wafer at a point 5 mm from the outer periphery to the center ｗ１ However, 0.80≦t ｗ１ / t ｗ０ 6 is a cross-sectional view showing an example of an optical resin wafer obtained by the method for producing an optical resin wafer according to the second embodiment, and the thickness t ｗ０ and the thickness t at a point 5 mm from the outer periphery to the center of the optical resin wafer ｗ１ However, 0.80≦t ｗ１ / t ｗ０ The relationship of ≦1.20 is satisfied.

[0069] When the molding surface of the mold used in this embodiment 2 is spherical, the curvature of the growth surface is 0.80 or more and ≦t ｗ１ / t ｗ０ It is preferable that the curvature satisfies the relationship: 0.85≦t ｗ１ / t ｗ０ It is more preferable that the curvature satisfies the relationship: 0.90≦t ｗ１ / t ｗ０ It is more preferable that the curvature satisfies the relationship: 0.95≦t ｗ１ / t ｗ０ It is particularly preferable that the curvature satisfies the relationship: 0.98≦t ｗ１ / t ｗ０ It is most preferable that the curvature of the growth surface of the mold satisfies the relationship t ｗ１ / t ｗ０ It is preferable that the curvature satisfies the relationship t≦1.15, ｗ１ / t ｗ０ It is more preferable that the curvature satisfies the relationship t≦1.10, ｗ１ / t ｗ０ It is more preferable that the curvature satisfies the relationship t≦1.05. ｗ１ / tｗ０ It is particularly preferable that the curvature satisfies the relationship t≦1.02. ｗ１ / t ｗ０ It is most preferable that the curvature be such that the value of the curvature is 1.00.

[0070] The material of the mold used in this embodiment 2, the material of the optical resin wafer manufactured in this embodiment 2, the curing conditions in the curing process of this embodiment 2, the type of processing in the processing process of this embodiment 2, the optical resin wafer manufactured in this embodiment 2, etc. are the same as those in this embodiment 1.

[0071] 2. Optical Resin Wafer The optical resin wafer of this embodiment will be described below.

[0072] The optical resin wafer of this embodiment can be obtained by the manufacturing method of the optical resin wafer of this embodiment 1 and the manufacturing method of the optical resin wafer of this embodiment 2.

[0073] The optical resin wafer manufactured by this embodiment 1 is, for example, an optical resin wafer 61 containing thiourethane resin, and has a hole 62 in the center of the optical resin wafer 61. The left diagram of Figure 7 is a top view that schematically shows an example of the optical resin wafer of this embodiment.

[0074] The preferred ranges of the average thickness and diameter of the optical resin wafer of this embodiment are as described above.

[0075] The optical resin wafer of this embodiment is used as a material for optical products, and therefore may be required to have improved flatness and smoothness and reduced thickness unevenness. This is required for the optical resin wafer of this embodiment. The preferred ranges of TTV, which is an index of flatness and thickness unevenness, and surface roughness Ra, which is an index of smoothness, are as described above.

[0076] The refractive index, cure shrinkage rate, linear expansion coefficient and uses of the optical resin wafer of this embodiment are as described above.

[0077] 3. Method for Manufacturing Optical Member Hereinafter, a method for manufacturing the optical member of this embodiment will be described.

[0078] The right diagram of FIG. 7 is a diagram schematically showing an example of a method for manufacturing an optical member of this embodiment. The method for manufacturing an optical member of this embodiment includes a step of obtaining a plurality of optical members 22 from the optical resin wafer 21 of this embodiment. The optical members 22 of this embodiment may be, for example, optical lenses, light guide plates, filters, or optical switches. FIG. 8 is a diagram schematically showing another example of a method for manufacturing an optical member of this embodiment. The method for manufacturing an optical member of this embodiment includes a step of obtaining a plurality of optical members 5 from the optical resin wafer 4 of this embodiment. The optical members 5 of this embodiment may be, for example, optical lenses, light guide plates, filters, or optical switches.

[0079] 4. Optical Member The optical member of this embodiment will now be described.

[0080] The optical member of this embodiment is obtained by the method for manufacturing an optical member of this embodiment.

[0081] The optical member of this embodiment can be used, for example, in an optical information transmission device, as described above.

[0082] An optical information transmission device using the optical element of this embodiment will be described with reference to Fig. 9. The optical information transmission device 20 includes a light irradiating unit 11 and the optical element 10 of this embodiment. Light 12 generated from the light irradiating unit 11 is reflected by the optical element 10 of this embodiment, and the reflected light is irradiated onto the user's eye 13. As a result, the light generated from the light irradiating unit 11 is recognized by the user wearing the optical information transmission device 20.

[0083] 5. Mold for Manufacturing Optical Resin Wafer Hereinafter, the mold for manufacturing optical resin wafers of this embodiment will be described.

[0084] The mold for manufacturing optical resin wafers of this embodiment is a mold for manufacturing optical resin wafers for manufacturing optical resin wafers, and one or more spacers are arranged in the center of the mold for manufacturing optical resin wafers of this embodiment.

[0085] The mold for manufacturing the optical resin wafer of this embodiment is preferably provided with a resin pouring passage used to pour the optical resin composition, so that the spacer also serves as the resin pouring passage, eliminating the need to provide a separate resin pouring passage, and further improving manufacturing efficiency.

[0086] The preferred aspects of the mold for manufacturing optical resin wafer of this embodiment and the spacer of the mold for manufacturing optical resin wafer of this embodiment are the same as the preferred aspects of the mold used in the manufacturing method of optical resin wafer of this embodiment described above, so the description here is omitted.

[0087] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations can be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention.

[0088] This application claims priority based on Japanese Patent Application Nos. 2023-221784 and 2023-221798, filed December 27, 2023, the disclosures of which are incorporated herein in their entirety by reference.

[0089] The present invention can also take the following aspects: [1] A method for producing an optical resin wafer, comprising a step A of injecting an optical resin composition into a mold and curing it to obtain an optical resin wafer, wherein the molding surface of the mold includes a curved surface, and the curved surface has a thickness t ｗ０ The thickness t of the optical resin wafer at a point 5 mm from the outer periphery toward the center ｗ１ The ratio of t ｗ１ / t ｗ０ [2] A method for manufacturing an optical resin wafer having a curvature such that the value of is 0.80 or more and 1.20 or less. ｍ０ The thickness at a point 5 mm from the outer periphery toward the center in the cavity space of the mold is t ｍ１ The method for producing an optical resin wafer according to [1], wherein the following formula (1) is satisfied when t ｍ０ >t ｍ１(1) [3] The method for producing an optical resin wafer according to [1] or [2], wherein the optical resin wafer contains one or more selected from the group consisting of (thio)urethane-based optical resins, epoxy-based optical resins, polycarbonate-based optical resins, episulfide-based optical resins, allyl carbonate-based optical resins, nylon-based optical resins, polyamide-based optical resins, and polyimide-based optical resins. [4] The method for producing an optical resin wafer according to [1] or [2], wherein the average thickness of the optical resin wafer is 0.1 mm or more and 3.0 mm or less. [5] The method for producing an optical resin wafer according to [1] or [2], wherein the diameter of the optical resin wafer is 50 mm or more and 350 mm or less. [6] The method for producing an optical resin wafer according to [1] or [2], wherein the flatness of the optical resin wafer is 350 μm or less. [7] A method for producing an optical resin wafer according to [1] or [2], wherein the refractive index of the optical resin wafer at a temperature of 25°C and a wavelength of 587.6 nm in accordance with JIS K-0062:1992 is 1.47 or more. [8] A method for producing an optical resin wafer according to [1] or [2], wherein the mold contains glass. [9] A method for producing an optical resin wafer according to [1] or [2], comprising a step B of polishing the optical resin wafer removed from the mold.

[10] A method for producing an optical resin wafer according to [1] or [2], comprising a step C of flattening the optical resin wafer by heating.

[11] A mold for producing an optical resin wafer for producing an optical resin wafer, wherein a molding surface of the mold for producing an optical resin wafer includes a curved surface, and the curved surface has a thickness t of the central part of the optical resin wafer. ｗ０ The thickness t of the optical resin wafer at a point 5 mm from the outer periphery toward the center ｗ１ The ratio of t ｗ１ / t ｗ０

[12] A mold for manufacturing optical resin wafers, having a curvature such that the value of is 0.80 or more and 1.20 or less. ｍ０ The thickness at a point 5 mm from the outer periphery toward the center in the cavity space of the mold for manufacturing the optical resin wafer is t ｍ１The mold for producing an optical resin wafer according to

[11] , which satisfies the following formula (1) when t ｍ０ >t ｍ１ (1)

[0090] The present invention can also take the following forms. <1> A method for producing an optical resin wafer, including step A of casting an optical resin composition into a mold and curing it to obtain an optical resin wafer, wherein one or more spacers are arranged in the center of the cavity space of the mold. <2> A method for producing an optical resin wafer according to <1>, wherein one or more spacers are arranged within a range of 25 mm from the edge of the cavity space of the mold toward the center. <3> A method for producing an optical resin wafer according to <2>, wherein spacers are arranged on 80% or more of the outer periphery of the mold. <4> A method for producing an optical resin wafer according to <1> or <2>, wherein the spacers have a cylindrical, polygonal pillar, or ring shape. <5> A method for producing an optical resin wafer according to <1> or <2>, wherein in step A, an optical resin composition is cast through a resin casting path provided in the spacer. <6> A method for producing an optical resin wafer according to <1> or <2>, wherein the optical resin wafer contains one or more resins selected from the group consisting of (thio)urethane-based optical resins, epoxy-based optical resins, polycarbonate-based optical resins, episulfide-based optical resins, allyl carbonate-based optical resins, nylon-based optical resins, polyamide-based optical resins, and polyimide-based optical resins. <7> A method for producing an optical resin wafer according to <1> or <2>, wherein the average thickness of the optical resin wafer is 0.1 mm or more and 3.0 mm or less. <8> A method for producing an optical resin wafer according to <1> or <2>, wherein the diameter of the optical resin wafer is 50 mm or more and 350 mm or less. <9> A method for producing an optical resin wafer according to <1> or <2>, wherein the flatness of the optical resin wafer is 350 μm or less. <10> The method for producing an optical resin wafer according to <1> or <2>, wherein the refractive index of the optical resin wafer at a temperature of 25°C and a wavelength of 587.6 nm in accordance with JIS K-0062: 1992 is 1.47 or more. <11> The volume V of the optical resin composition before curing measured in accordance with JIS K-6941-2-4: 2014 ０and the volume after hardening V １ The method for producing an optical resin wafer according to <1> or <2>, wherein the curing shrinkage obtained by the following formula (1) is 15% or less. Curing shrinkage (%) = (V １ -V ０ ) / V ０ (1) <12> The method for manufacturing an optical resin wafer according to <1> or <2>, wherein the spacer comprises one or more types selected from the group consisting of glass, ceramic, metal, and resin. <13> An optical resin wafer comprising a thiourethane resin, wherein the optical resin wafer has a hole in the center. <14> A mold for manufacturing an optical resin wafer, wherein one or more spacers are arranged in the center of the mold for manufacturing an optical resin wafer.

[0091] REFERENCE SIGNS LIST 1 Optical resin wafer 2 Mold 4 Optical resin wafer 5 Optical member 10 Optical member 11 Light irradiation unit 12 Light 13 Eye 20 Optical information transmission device 21 Optical resin wafer 22 Optical member 51 Mold 52 Cavity space 53 Center part of cavity space 54 Spacer 55 End part of cavity space 61 Optical resin wafer 62 Hole t ｗ０ Thickness t of the central part of the optical resin wafer 1 ｗ１ The thickness t at a point 5 mm from the outer periphery toward the center of the optical resin wafer 1 ｍ０ Width t of the center of the cavity space of the mold 2 ｍ１ Width of the cavity space of the mold 2 at a point 5 mm from the outer periphery toward the center

Claims

1. A method for manufacturing an optical resin wafer, comprising: a mold preparation step of preparing a mold satisfying the following (a) or (b); and a curing step of casting a curable composition as a raw material of the optical resin wafer into the mold and curing it to obtain a precursor of the optical resin wafer. (a) The mold has one or more spacers at the center of the cavity space. (b) The relationship between the thickness t ｍ０ at the center of the cavity space of the mold and the thickness t ｍ１ at a point 5 mm from the outer peripheral portion to the center of the cavity space of the mold is such that t ｍ０ > t ｍ１ .

2. A processing step of obtaining an optical resin wafer by performing at least one processing selected from the group consisting of notch processing, burr processing, beveling processing, cutting processing, grinding processing, polishing processing, and heat processing on the optical resin wafer precursor, the method for manufacturing an optical resin wafer according to claim 1, further comprising this step.

3. The method for manufacturing an optical resin wafer according to claim 1, wherein the mold satisfies the above (a) and has one or more spacers in a range within 25 mm from the end portion to the central portion of the cavity space.

4. The method for manufacturing an optical resin wafer according to claim 3, wherein the mold satisfies the above (a), and the spacers are arranged so as to occupy 80% or more of the outer periphery of the cavity space.

5. The method for manufacturing an optical resin wafer according to claim 1, wherein the mold satisfies the above (a), and the shape of the spacer is cylindrical, polygonal columnar, cylindrical, or square tube-shaped.

6. The method for manufacturing an optical resin wafer according to claim 1, wherein the mold satisfies the above (a), and the spacer has a structure that allows the curable composition to be cast into the cavity space.

7. The method for manufacturing an optical resin wafer according to claim 1, wherein the mold satisfies the above (a), and the spacer contains at least one selected from the group consisting of glass, ceramic, metal, and resin.

8. The method for manufacturing an optical resin wafer according to claim 1, wherein the mold contains glass.

9. The method for manufacturing an optical resin wafer according to claim 1, wherein the optical resin wafer contains at least one selected from the group consisting of (thio)urethane-based optical resins, epoxy-based optical resins, polycarbonate-based optical resins, episulfide-based optical resins, allyl carbonate-based optical resins, nylon-based optical resins, polyamide-based optical resins, and polyimide-based optical resins.

10. The method for manufacturing an optical resin wafer according to claim 1, wherein the refractive index of the optical resin wafer is 1.47 or more.

11. The method for producing an optical resin wafer according to claim 1, wherein the curing shrinkage rate A of the curable composition calculated by the following formula (x) is 15% or less. A = (V ０ - V １ ) / V ０ × 100 (x) A: Curing shrinkage rate [%] V ０ : Volume of the curable composition (before curing) V １ : Volume of the optical resin wafer precursor (after curing) 12. The method for manufacturing an optical resin wafer according to claim 1, wherein the average thickness of the optical resin wafer is 0.1 mm to 3.0 mm.

13. The method for manufacturing an optical resin wafer according to claim 1, wherein the diameter of the optical resin wafer is 50 mm to 350 mm.

14. The method for manufacturing an optical resin wafer according to claim 1, wherein the flatness of the optical resin wafer is 350 μm or less.

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