JP2007133110A - Method for manufacturing lens substrate, lens substrate, transmission type screen and rear type projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens substrate capable of displaying an excellent picture excellent in contrast and restrained from generating a bright spot, and to provide a transmission type screen equipped with the lens substrate and a rear type projector. <P>SOLUTION: The method for manufacturing the lens substrate includes: a stage for inspecting whether or not a flat part 79 having predetermined size or more exists between adjacent recessed parts 71 and 71 on the surface on a side provided with the recessed part 71 of a member 7 with the recessed part having the recessed part 71 corresponding to a convex lens 21 to be formed, and applying light shielding material 4 to the flat part 79 if the flat part 79 exists; a stage for applying a composition 23 having fluidity onto the member 7 with the recessed part; a stage for obtaining a substrate body 2 by solidifying the composition 23; a stage for applying light shielding film forming material 32 for forming a light shielding film 3 on a surface side opposite to the lens surface of the substrate body 2; and a stage for forming a light shielding part 3 having an aperture part 31 by performing processing to irradiate the light shielding film forming material 32 with light through the substrate body 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lens substrate manufacturing method, a lens substrate, a transmissive screen, and a rear projector.

In recent years, the demand for rear projectors is increasing as a display suitable for home theater monitors, large-screen televisions, and the like.
A lens substrate having a lenticular lens (lens portion) is generally used for a transmissive screen used in a rear projector. In such a lens substrate (lens sheet), a light-shielding layer is provided on the side opposite to the side where the lens portion is provided for the purpose of improving the contrast of the image.

  In the manufacture of such a lens substrate (lens sheet), generally, a light-shielding layer having an opening (light-transmitting portion) is formed by using light condensing in the lens portion (for example, Patent Document 1). By forming the light-shielding layer by such a method, an opening (light-transmitting portion) can be formed at a portion corresponding to the focal point of the lens portion, which is advantageous in improving contrast. .

By the way, when manufacturing such a lens substrate, generally, a molding die having a concave portion corresponding to the lens portion is used. However, a lens to be formed is formed on the lens substrate to be formed due to a defective molding die or the like. There is a case where there is a region that is not formed, or a lens that is smaller than other lenses is formed. When there is such a defect in the lens part, when applying the light shielding layer forming method as described above, the part of the light shielding layer corresponding to the part where the lens part is not provided (flat part), An opening is formed. When such an opening is formed, light that is not refracted by the lens portion in a transmission screen or the like is emitted to the observer side as straight light. Such straight light is recognized as a bright spot (white spot) on the screen and has a significant adverse effect on the displayed image.
By using a mold that does not have a defect in the concave portion corresponding to the lens portion, the above problems can be prevented and suppressed. However, it is possible to produce a mold without such a defect. ,Have difficulty.

  On the other hand, with the recent increase in the size of displays and screens, a large lens substrate is required. In the mold used for manufacturing such a large lens substrate, the occurrence of the above-described defects is prevented. It was extremely difficult. In addition, when trying to manufacture a mold for manufacturing a large lens substrate without the above-mentioned defects, the yield is very bad, which greatly affects the productivity and manufacturing cost of the lens substrate. End up.

JP 2004-361875 A

  An object of the present invention is to provide a lens substrate that can display an excellent image with excellent contrast and suppressed generation of bright spots, and a manufacturing method that can efficiently manufacture the lens substrate. It is another object of the present invention to provide a transmissive screen and a rear projector provided with the lens substrate.

Such an object is achieved by the present invention described below.
The method for producing a lens substrate according to the present invention is a method for producing a lens substrate having a substrate body having a large number of convex lenses and a light-shielding film made of a light-shielding material and having an opening.
Preparing a member with a recess having a recess corresponding to the convex lens;
A light-shielding material is applied to the top of a convex portion having a height higher than a predetermined value among the convex portions existing between adjacent concave portions on the surface of the member with the concave portion where the concave portion is provided. A light-shielding material application step,
A composition applying step for applying a composition having fluidity to the surface of the recessed portion of the member provided with the recess;
Solidifying the composition to obtain a substrate body;
A light-shielding film-forming material application step for applying a light-shielding film-forming material for forming the light-shielding film on the surface of the substrate body opposite to the surface on which the convex lens is provided;
An opening forming step of performing light irradiation on the light shielding film forming material through the substrate body to form the light shielding portion having the opening.
Accordingly, it is possible to provide a manufacturing method that can efficiently manufacture a lens substrate that can display an excellent image with excellent contrast and suppressed generation of bright spots.

In the lens substrate manufacturing method of the present invention, it is preferable that the top of the convex portion to which the light shielding material is applied is a flat portion that does not function as a lens portion.
Thereby, generation | occurrence | production of the bright spot in the displayed image can be prevented more effectively.
The method for producing a lens substrate according to the present invention is a method for producing a lens substrate having a substrate body having a large number of convex lenses and a light-shielding film made of a light-shielding material and having an opening.
Preparing a member with a recess having a recess corresponding to the convex lens;
On the surface on the side where the concave portion of the member with concave portions is provided, it is inspected whether a flat portion having a predetermined size or more exists between adjacent concave portions, and the flat portion exists. In the case, a light-shielding material application step of applying a light-shielding material to the flat portion,
A composition applying step for applying a composition having fluidity to the surface of the recessed portion of the member provided with the recess;
Solidifying the composition to obtain a substrate body;
A light-shielding film-forming material application step for applying a light-shielding film-forming material for forming the light-shielding film on the surface of the substrate body opposite to the surface on which the convex lens is provided;
An opening forming step of performing light irradiation on the light shielding film forming material through the substrate body to form the light shielding portion having the opening.
Accordingly, it is possible to provide a manufacturing method that can efficiently manufacture a lens substrate that can display an excellent image with excellent contrast and suppressed generation of bright spots.

In the manufacturing method of the lens substrate of this invention, it is preferable to provide the said light-shielding material by roller application | coating in the said light-shielding material provision process.
Thereby, the light-shielding material can be selectively and selectively applied to a desired site easily and reliably.
In the manufacturing method of the lens substrate of this invention, it is preferable to provide the said light-shielding material with the thickness of 0.8-1.2 micrometers in the said light-shielding material provision process.
Thereby, while making the light-shielding property in the part to which the light-shielding material was applied in the light-shielding material application process particularly excellent, the substrate body and the light-shielding part (lens surface side light-shielding part) made of the light-shielding material Adhesiveness can be made sufficiently excellent. For example, when the member with a recess is removed from the substrate body, it is possible to effectively prevent the light-shielding part from peeling off unintentionally.

In the lens substrate manufacturing method of the present invention, it is preferable to have a concave member removal step of removing the concave member from the substrate body after the solidification step.
Thereby, the member with a recessed part can be repeatedly used for manufacture of a lens board | substrate, and the productivity of a lens board | substrate improves.
In the method for manufacturing a lens substrate according to the present invention, it is preferable that the member with recessed portion removing step is provided after the opening forming step.
Thereby, a relatively large opening can be formed more reliably, and the viewing angle characteristics can be made particularly excellent.

In the lens substrate manufacturing method of the present invention, the convex lens to be formed has a spherical surface, and the distance between the tops of the adjacent convex lenses of the lens substrate is set to 2 as the radius of curvature of the convex lens to be formed. It is preferable that the value is smaller than the multiplied value.
Thereby, in a light-shielding material provision process, a light-shielding material can be provided more selectively with respect to the site | part which should provide the light-shielding material of a member with a recessed part. In addition, the light utilization efficiency of the lens substrate can be made particularly excellent.

In the lens substrate manufacturing method of the present invention, the lens substrate is preferably a microlens substrate including a microlens as the convex lens.
Thereby, the viewing angle characteristic in each direction (for example, the vertical direction and the horizontal direction) can be made particularly excellent. Further, in the manufacture of the microlens substrate, it is easy to cause a defect of the lens portion, and thereby, a bright spot or the like due to straight light is particularly likely to occur in the displayed image. Also, the occurrence of bright spots can be sufficiently prevented. Therefore, by applying the present invention to the manufacture of the microlens substrate, the effect is more remarkably exhibited.

In the method for manufacturing a lens substrate according to the present invention, it is preferable that a mold release process is performed on a surface of the member having the recesses on the side where the recesses are provided.
Thereby, the light-shielding material (lens surface side light-shielding part) provided to the member with a recessed part can be more reliably transferred from the member with a recessed part to the substrate body side.
The lens substrate of the present invention is manufactured using the method of the present invention.
Accordingly, it is possible to provide a lens substrate that can display an excellent image with excellent contrast and suppressed generation of bright spots.

The lens substrate of the present invention is a lens substrate having a substrate body having a large number of convex lenses and a light-shielding film made of a light-shielding material and having an opening,
On the surface of the substrate body on the side where the convex lens is provided, a flat portion having a predetermined size or more is provided between the adjacent convex lens and the convex lens.
A lens surface side light shielding part made of a light shielding material is selectively provided on the flat part.
Accordingly, it is possible to provide a lens substrate that can display an excellent image with excellent contrast and suppressed generation of bright spots.

The transmission screen of the present invention is characterized by including the lens substrate of the present invention.
As a result, it is possible to provide a transmissive screen capable of displaying an excellent image with excellent contrast and suppressed generation of bright spots.
The transmissive screen of the present invention, a Fresnel lens portion in which a Fresnel lens is formed on the light emission side,
And a lens substrate of the present invention disposed on the light emission side of the Fresnel lens portion.
As a result, it is possible to provide a transmissive screen capable of displaying an excellent image with excellent contrast and suppressed generation of bright spots.
A rear projector according to the present invention includes the transmission screen according to the present invention.
Accordingly, it is possible to provide a rear projector that can display an excellent image with excellent contrast and suppressed generation of bright spots.

Hereinafter, a lens substrate manufacturing method, a lens substrate, a transmissive screen, and a rear projector according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
In the present invention, the “substrate” refers to a concept that is substantially inflexible and includes a relatively large thickness, a sheet-like material, a film-like material, and the like. .
The use of the lens substrate of the present invention is not particularly limited, but in the following description, the lens substrate will be described as being mainly used as a member constituting a transmissive screen and a rear projector.

First, prior to the description of the manufacturing method of the lens substrate of the present invention, the configurations of the lens substrate (convex lens substrate) and the transmissive screen of the present invention will be described.
1 is a schematic longitudinal sectional view showing a preferred embodiment of a lens substrate (microlens substrate) of the present invention, FIG. 2 is a plan view of the lens substrate (microlens substrate) shown in FIG. 1, and FIG. FIG. 2 is a schematic longitudinal sectional view showing a preferred embodiment of the transmission screen of the present invention including the lens substrate (microlens substrate) shown in FIG. 1. In the following description, the left side in FIGS. 1 and 3 is referred to as “(light) incident side”, and the right side is referred to as “(light) emission side”. In the present invention, unless otherwise specified, the “(light) incident side” and the “(light) output side” are the “incident side” of light for obtaining image light (video light), respectively. ”And“ outgoing side ”, not“ incident side ”or“ outgoing side ”of external light or the like.

  A microlens substrate (lens substrate) 1 is a member constituting a transmission screen 10 to be described later, and includes a plurality of microlenses (convex lenses) 21 arranged in a predetermined pattern as shown in FIG. A main body 2, a black matrix (light-shielding film) 3 made of a light-shielding material, a lens surface-side light-shielding portion 4 provided on the surface side of the substrate main body 2 on which a microlens (convex lens) 21 is provided, And a diffusion unit 5 having a function of diffusing incident light by irregular reflection.

The substrate body 2 is usually made of a transparent material.
As a constituent material of the substrate body 2, for example, various resin materials, various glass materials, and the like can be used. From the viewpoint of productivity of the substrate body 2, adhesion to the lens surface side light-shielding portion 4, and the like, the resin material Is preferred.
Examples of the resin material constituting the substrate body 2 include polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), cyclic polyolefin, modified polyolefin, polyvinyl chloride, and polychlorinated. Vinylidene, polystyrene, polyamide (eg, nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 6-12, nylon 6-66), polyimide, polyamideimide, polycarbonate (PC), Poly- (4-methylpentene-1), ionomer, acrylic resin, acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer Polyoxymethylene, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyester such as polycyclohexane terephthalate (PCT), polyether, polyether ketone (PEK), polyether ether ketone (PEEK), polyether imide, polyacetal (POM), polyphenylene oxide, modified polyphenylene oxide, polysulfone, polyether sulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), poly Tetrafluoroethylene, polyvinylidene fluoride, other fluororesins, styrene, polyolefin, polyvinyl chloride, polyurea , Polyester, polyamide, polybutadiene, transpolyisoprene, fluororubber, chlorinated polyethylene, and other thermoplastic elastomers, epoxy resins, phenolic resins, urea resins, melamine resins, unsaturated polyesters, silicones Resins, urethane-based resins, etc., or copolymers, blends, polymer alloys, etc. mainly composed of these, and combinations of one or more of these (for example, blend resins, polymer alloys, laminates) As body etc.).

  The constituent material (solidified material) of the substrate body 2 generally has an absolute refractive index greater than various gases (the atmosphere in which the microlens substrate 1 is used), but the specific value of the absolute refractive index is 1.4 to 1.58 is preferable, and 1.5 to 1.56 is more preferable. When the absolute refractive index of the constituent material of the substrate body 2 is a value within the above range, the viewing angle characteristic can be made particularly excellent while making the utilization efficiency of light (incident light) particularly excellent.

The microlens substrate 1 includes a plurality of microlenses 21 as convex lenses having a convex surface on the light incident surface side.
In the present embodiment, the microlens (convex lens) 21 has a flat shape (substantially oval or substantially elliptical) in which the vertical width (vertical width) when the microlens substrate 1 is viewed in plan is smaller than the horizontal width (horizontal width). It has a bowl shape. When the microlens 21 has such a shape, it is possible to make the viewing angle characteristics particularly excellent while effectively preventing the occurrence of inconvenience such as moire. In particular, both the horizontal and vertical viewing angle characteristics can be improved.

When the length in the minor axis direction (longitudinal direction) of the microlens 21 in plan view is L ₁ [μm] and the length in the major axis direction (lateral direction) is L ₂ [μm], 0.50 ≦ It is preferable to satisfy the relationship of L ₁ / L ₂ ≦ 0.99, more preferably satisfy the relationship of 0.60 ≦ L ₁ / L ₂ ≦ 0.90, and 0.65 ≦ L ₁ / L ₂ More preferably, the relationship of ≦ 0.80 is satisfied. By satisfying the relationship as described above, the effects as described above become more remarkable.

  The length of the microlens 21 in the short axis direction (vertical width of the microlens 21) in plan view is preferably 10 to 200 μm, more preferably 30 to 150 μm, and 50 to 100 μm. Is more preferable. When the length of the microlens 21 in the short axis direction is a value within the above range, it is possible to obtain sufficient resolution in the image projected on the screen while effectively preventing the occurrence of inconvenience such as moire. The productivity of the microlens substrate 1 (transmission type screen 10) can be further increased.

  Further, the length of the microlens 21 in the major axis direction (horizontal width of the microlens 21) in plan view is preferably 15 to 250 μm, more preferably 45 to 200 μm, and 70 to 150 μm. Is more preferable. When the length of the microlens 21 in the short axis direction is a value within the above range, it is possible to obtain sufficient resolution in the image projected on the screen while effectively preventing the occurrence of inconvenience such as moire. The productivity of the microlens substrate 1 (transmission type screen 10) can be further increased.

  Further, the radius of curvature of the microlens 21 is preferably 7.5 to 375 μm, more preferably 30 to 180 μm, and further preferably 70 to 120 μm. When the radius of curvature of the microlens 21 is a value within the above range, the viewing angle characteristics can be made particularly excellent. In particular, both the horizontal and vertical viewing angle characteristics can be improved. The microlens 21 may have a different radius of curvature in the minor axis direction and a radius of curvature in the major axis direction. In such a case, the radius of curvature in the major axis direction is a value within the above range. Is preferred.

The height of the microlens 21 is preferably 7.5 to 375 μm, more preferably 30 to 180 μm, and even more preferably 70 to 120 μm. When the height of the microlens 21 is within the above range, the light utilization efficiency and viewing angle characteristics can be made particularly excellent.
The microlens (convex lens) 21 has a spherical surface, and the distance (pitch) between the apexes of adjacent microlenses 21 is smaller than the value obtained by multiplying the curvature radius of the microlens 21 by 2. Is preferred. Thereby, in the manufacturing method of the microlens board | substrate (lens board | substrate) 1 which is mentioned later, the lens surface side light-shielding part 4 can be selectively formed by the target site | part, and the displayed image is more suitable. It can be. Further, the light utilization efficiency of the microlens substrate 1 can be made particularly excellent.

  The plurality of microlenses 21 are arranged in a staggered pattern (in a staggered pattern). By arranging the microlenses 21 in this way, it is possible to effectively prevent inconveniences such as moire. On the other hand, for example, if the microlenses are arranged in a square lattice shape or the like, it may be difficult to sufficiently prevent the occurrence of inconvenience such as moire depending on the size of the microlenses 21 and the like. . Further, when the microlenses are randomly arranged, depending on the size of the microlens 21 or the like, it becomes difficult to sufficiently increase the occupation ratio of the microlenses in the effective region where the microlenses are formed. It is difficult to sufficiently increase the transmittance (light utilization efficiency), and the obtained image may be dark.

  As described above, in the present embodiment, the microlenses 21 are arranged in a staggered pattern when the microlens substrate 1 is viewed in plan view. However, the first row includes a plurality of microlenses 21. 25 and the second row 26 adjacent thereto are preferably shifted by a half pitch in the vertical direction (the minor axis direction of the microlens 21). As a result, it is possible to more effectively prevent the occurrence of moire due to light interference and to make the viewing angle characteristics particularly excellent.

  The arrangement method of the microlenses 21 is not limited to the one described above. For example, even if the arrangement is a square lattice, the arrangement is optically random (from the main surface side of the microlens substrate 1 in plan view). In this case, the microlenses 21 may be arranged in a random positional relationship with each other.

  Further, when the microlens substrate 1 is viewed in plan from the light incident surface side (direction shown in FIG. 2), the occupation ratio of the microlens 21 is 95 to 115 in the effective region where the microlens 21 is formed. % Is preferred. When the occupation ratio of the microlens 21 is a value within the above range, the light use efficiency can be further improved, and the brightness and contrast of the projected image can be made particularly excellent.

  As described above, by strictly defining the shape and arrangement method of the microlenses, the viewing angle characteristics and the like can be made particularly excellent while effectively preventing the occurrence of moire due to light interference. . In particular, by strictly defining the shape and arrangement method of the microlens as described above, the microlens is formed by the effect of having the microlens having the shape and arrangement method as described above and the method described in detail later. The effects of having the black matrix 3 act synergistically, and particularly excellent effects (for example, particularly excellent viewing angle characteristics, light utilization efficiency, etc.) can be obtained.

  Each microlens 21 is formed as a convex lens protruding to the incident side, and the focal point f is positioned in the vicinity of the opening (non-light-shielding part) 31 provided in the black matrix (light-shielding film) 3. Designed. That is, parallel light La (parallel light La from a Fresnel lens unit 6 described later) incident on the microlens substrate 1 from a substantially perpendicular direction is collected by each microlens 21 of the microlens substrate 1 and is black. A focal point f is formed in the vicinity of the opening 31 of the matrix 3. As described above, the microlens 21 is focused in the vicinity of the opening 31 of the black matrix 3 so that the light utilization efficiency can be made particularly excellent. As a result, the contrast of an image formed by light transmitted through the microlens substrate can be made particularly excellent.

In the microlens substrate 1, on the surface (lens surface) side of the substrate body 2 where the microlenses 21 are provided, the flat portion 28 having a predetermined size or more is disposed between the adjacent microlenses 21. Is present, the lens surface side light shielding portion 4 made of a light shielding material is selectively provided on the flat portion 28.
By providing such a lens surface side light-shielding portion 4, the light incident on the portion corresponding to the flat portion 28 of the substrate body 2 is emitted from the emission side of the microlens substrate 1 as straight light. Can be prevented. As a result, it is possible to effectively prevent bright spots (white spots) from appearing in the displayed image. In addition, by providing such a lens surface side light-shielding portion 4, when the black matrix 3 is formed by using the condensing by the microlens 21 as will be described later, an opening is provided in addition to the condensing portion of the microlens 21. 31 can be prevented from being formed.

  In the present invention, the “flat portion” refers to a portion not provided with unevenness that functions as a lens portion (a portion corresponding to this in a member with a recessed portion to be described later). A portion where the surface roughness Ra (for example, unevenness having a surface roughness Ra of about 5 μm or less) exists is also included in the flat portion. Further, in the present invention, the “flat portion having a predetermined size or more” means that the image is visually recognized in the displayed image, such as generation of a bright spot, when the lens surface side light shielding portion 4 is not provided. It refers to a flat portion having a size that has an adverse effect, for example, a flat portion having a width (length) of 5 μm or more. In general, the occurrence of the above-described problem becomes particularly noticeable when the width (length) of the flat portion is 8 μm or more.

  Although the thickness of the lens surface side light-shielding part 4 is not specifically limited, It is preferable that it is 0.5-5 micrometers, and it is more preferable that it is 0.8-1.5 micrometers. When the thickness of the lens surface side light-shielding part 4 is a value within the above range, the light shielding property by the lens surface side light-shielding part 4 can be made sufficiently excellent. Thereby, generation | occurrence | production of the luminescent spot, etc. by a straight light can be prevented more reliably. Further, the contrast of the displayed image can be made particularly excellent. On the other hand, when the thickness of the lens surface side light shielding portion 4 is less than the lower limit value, there is a possibility that sufficient light shielding properties may not be obtained. On the other hand, when the thickness of the lens surface side light-shielding part 4 exceeds the upper limit, the adhesion between the substrate body 2 and the lens surface side light-shielding part 4 is lowered, and the durability and reliability of the microlens substrate 1 are lowered. there is a possibility.

Although the lens surface side light-shielding part 4 should just have light-shielding property, it is preferable that the color is black. Thereby, the light-shielding property by the lens surface side light-shielding part 4 becomes especially excellent, and the contrast of the displayed image can be made particularly excellent.
A black matrix 3 is provided on the surface of the substrate body 2 on the light emission side. The black matrix 3 is made of a light-shielding material and is formed in a film shape. By having such a black matrix 3, the black matrix 3 can absorb external light (external light that is not preferable for forming a projection image), and the image projected on the screen has excellent contrast. Can be. In particular, by having the lens surface side light-shielding portion 4 as described above and the black matrix 3, the contrast of the image by the microlens substrate 1 can be made particularly excellent.

Such a black matrix 3 has an opening 31 on the optical path of the light transmitted through each microlens 21. Thereby, the light condensed by each micro lens 21 can be efficiently passed through the opening 31 of the black matrix 3. As a result, the light utilization efficiency of the microlens substrate 1 can be increased.
The opening 31 sufficiently prevents the light for image formation from being absorbed and reflected by the black matrix 3 while effectively preventing reflection of external light at a portion other than the opening 31 of the black matrix 3. It is provided with a large size. In the present invention, the “opening” refers to a portion through which light can be transmitted in a light-shielding film having light-shielding properties, and is filled with a material that is not substantially colored (a material having light-transmissive properties). It is a concept that includes such parts.

As will be described in detail later, the black matrix 3 is prevented from forming an opening at a portion not corresponding to the lens. Thereby, the viewing angle characteristics and light utilization efficiency of the microlens substrate 1 can be made particularly excellent, and the contrast of the projected image can be made higher.
The opening 31 of the black matrix 3 may have any shape, but it is preferable that the shape when viewed in plan is substantially circular. When the opening 31 is substantially circular, the size of the opening 31 is not particularly limited, but the diameter is preferably 5 to 80 μm, more preferably 15 to 60 μm, and 20 to 50 μm. More preferably. Thereby, the image projected on a screen can be made more excellent in contrast.

  Further, the thickness (average thickness) of the black matrix 3 is preferably 0.3 to 8 μm, more preferably 0.6 to 5 μm, and further preferably 0.8 to 1.5 μm. preferable. When the thickness of the black matrix 3 is a value within the above range, the function as the black matrix 3 (that is, the image contrast is improved) while preventing unintentional peeling and cracking of the black matrix 3 more reliably. For example, in the transmission screen 10 including the microlens substrate 1, the contrast of the projected image can be made particularly excellent.

  Further, the area ratio (opening ratio) of the opening 31 to the black matrix 3 when viewed in plan is preferably 60 to 97%, more preferably 70 to 95%, and 75 to 90%. Is more preferable. If the aperture ratio is a value within the above range, external light (for example, external light incidentally incident from the side opposite to the light incident side) is sufficiently suppressed from reflecting to the output side. In addition to making the light utilization efficiency particularly excellent, it is possible to prevent the reflection and make the contrast of the obtained image particularly excellent, and the viewing angle characteristics of the microlens substrate 1 are particularly excellent. Can be. On the other hand, if the aperture ratio is less than the lower limit, it may be difficult to make the light utilization efficiency and viewing angle characteristics sufficiently excellent. Also, if the aperture ratio exceeds the upper limit, it becomes difficult to keep external light reflection sufficiently low, and it becomes difficult to prevent reflection and make the contrast of the obtained image sufficiently excellent. there is a possibility.

  Further, a diffusing portion 5 is provided on the light emitting side surface of the microlens substrate 1. The diffusion unit 5 has a function of diffusing incident light (incident light) by irregular reflection. By having such a diffusion part 5, the viewing angle characteristics can be made particularly excellent. Further, since the diffuser 5 is provided, it is possible to diffusely reflect light, so that generation of bright spots in the displayed image can be more effectively prevented. Further, the diffusion portion 5 has a region formed on the light emission side from the black matrix 3. With such a configuration, the light incident on the diffusing portion 5 can be efficiently directed to the emission side (the direction opposite to the light incident side), and the light utilization efficiency is reduced. While effectively preventing, the viewing angle characteristics of the transmissive screen 10 can be made particularly excellent (the viewing angle at which an image projected on the screen can be suitably viewed is particularly large). it can). In the present embodiment, the diffusing portion 5 has a configuration in which a diffusing material is dispersed in a substantially transparent material (for example, an acrylic resin, a polycarbonate resin, etc.) excellent in light transmittance. As the diffusing material, for example, particulate (bead-shaped) silica, glass, resin, or the like can be used. The average particle size of the diffusing material is not particularly limited, but is preferably 1 to 50 μm, and more preferably 2 to 10 μm.

  Moreover, although the thickness of the spreading | diffusion part 5 is not specifically limited, It is preferable that it is 0.5-10 mm, It is more preferable that it is 0.7-5 mm, It is further more preferable that it is 1.0-3 mm. When the thickness of the diffusing portion 5 is a value within the above range, the viewing angle characteristics can be made particularly excellent while sufficiently improving the light utilization efficiency. On the other hand, if the thickness of the diffusing portion 5 is less than the lower limit, the effect of providing the diffusing portion 5 may not be sufficiently exhibited. Further, when the thickness of the diffusing portion 5 exceeds the upper limit value, the probability (frequency) that the light (photon) collides with the diffusing material tends to be rapidly increased, quenching is likely to occur, and in the diffusing portion. There is a high possibility that the incident light (photon) returns to the incident side again. As a result, it may be difficult to sufficiently increase the light use efficiency.

Next, the transmission screen 10 including the microlens substrate 1 as described above will be described.
As shown in FIG. 3, the transmission screen 10 includes a Fresnel lens portion 6 and the microlens substrate 1 described above. The Fresnel lens unit 6 is installed on the light (image light) incident side, and the light transmitted through the Fresnel lens unit 6 is incident on the microlens substrate 1.
The Fresnel lens portion 6 has a prism-shaped Fresnel lens 61 formed on the exit side surface in a substantially concentric shape. The Fresnel lens unit 6 refracts image light from a projection lens (not shown) to make parallel light La parallel to the vertical direction of the main surface of the microlens substrate 1.

  In the transmissive screen 10 configured as described above, the image light from the projection lens is refracted by the Fresnel lens unit 6 to become parallel light La. The parallel light La is incident from the side of the microlens substrate 1 on which the microlenses 21 are formed, collected by the microlenses 21, diffused after being focused. The light that has passed through the opening 31 diffuses and is observed as a planar image by the observer.

Next, an example of a method for manufacturing the above-described microlens substrate 1 will be described.
4 is a schematic longitudinal sectional view showing a member with a recess used for manufacturing a microlens substrate, FIG. 5 is a schematic longitudinal sectional view showing a method for manufacturing the member with a recess shown in FIG. 4, FIG. 6 and FIG. 7 is a schematic longitudinal sectional view showing an example of a manufacturing method of the microlens substrate shown in FIG. 1, FIG. 8 is a schematic view showing an inspection apparatus used in manufacturing the microlens substrate, and FIG. FIG. 10 is a schematic view showing an inspection / repair device used in the manufacture of a member with a recess. In the following description, the lower side in FIGS. 5, 6, 7, and 9 is the “(light) incident side”, and the upper side in FIGS. 5, 6, 7, and 9 is the “(light) side”. )).

Further, in the manufacture of the member with concave portions, a large number of concave portions (recesses for microlenses) are actually formed on the substrate, and in the manufacture of the microlens substrate (substrate body), actually a large number of convex portions (convex lenses). However, in order to make the explanation easier to understand, a part thereof is highlighted.
First, prior to the description of the manufacturing method of the microlens substrate, the configuration of the member with recesses (the member with recesses for forming microlenses) used for manufacturing the microlens substrate will be described.

  The member with recesses (member with recesses for forming microlenses) 7 may be made of any material, but is preferably made of a material that is less likely to bend and is less likely to be damaged. As a constituent material of the member 7 with a recessed part, various glass materials, various resin materials, etc. are mentioned, for example. Examples of the glass material include soda glass, crystalline glass, quartz glass, lead glass, potassium glass, borosilicate glass, and alkali-free glass. Examples of the resin material include polyethylene, polypropylene, and ethylene- Polyolefin such as propylene copolymer, ethylene-vinyl acetate copolymer (EVA), cyclic polyolefin, modified polyolefin, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide (eg, nylon 6, nylon 46, nylon 66, nylon 610) , Nylon 612, nylon 11, nylon 12, nylon 6-12, nylon 6-66), polyimide, polyamideimide, polycarbonate (PC), poly- (4-methylpentene-1), ionomer, acrylic resin, acryloni Ryl-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyoxymethylene, polyvinyl alcohol (PVA), ethylene-vinyl alcohol copolymer (EVOH) ), Polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polycyclohexane terephthalate (PCT), polyether, polyetherketone (PEK), polyetheretherketone (PEEK), polyetherimide, polyacetal (POM) ), Polyphenylene oxide, modified polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer) Polytetrafluoroethylene, polyvinylidene fluoride, other fluororesins, styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, fluoro rubber, chlorinated polyethylene Various thermoplastic elastomers such as epoxy resins, phenol resins, urea resins, melamine resins, unsaturated polyesters, silicone resins, urethane resins, etc., or copolymers, blends, polymer alloys, etc. mainly comprising these A resin material etc. are mentioned, Among these, it can use combining 1 type (s) or 2 or more types. Among these, as a constituent material of the member 7 with a recessed part, a glass material is preferable and soda glass, crystalline glass (for example, neo-ceram etc.), and an alkali free glass are more preferable. Such a material is generally excellent in shape stability. Therefore, the stability (reliability) of the shape of the recess 71 included in the member 7 with the recess, the dimensional accuracy of the microlens 21 formed using the recess 71, and the like can be made particularly excellent. The optical characteristics of the substrate can be made particularly reliable. In addition, since the glass material is generally excellent in shape stability, in the method for manufacturing the microlens substrate 1 described in detail later, the handleability of the manufactured substrate body 2 is improved. Further, soda glass, crystalline glass, and non-alkali glass are easy to process, are relatively inexpensive, and are advantageous from the viewpoint of manufacturing cost. In addition, since the glass material as described above has high transparency and a suitable refractive index, as described in detail later, in the state in which the member 7 with the recess is attached to the substrate body 2, the opening portion is preferably formed. A forming step can be performed. Thereby, the opening part 31 of a suitable magnitude | size can be formed easily and reliably.

  The recessed member 7 has a refractive index (absolute refractive index) larger than various gases (for example, air, various inert gases, etc.), and is a constituent material of the base body 2 (a solidified constituent material). It is preferable that it is made of a material having a smaller refractive index (absolute refractive index). As a result, in a method that will be described in detail later, the photopolymer 32 can be irradiated with light having an optimal light intensity distribution, whereby the opening 31 having an optimal size can be formed more efficiently. .

Although the absolute refractive index of the constituent material of the member 7 with a recessed part is not specifically limited, It is preferable that it is 1.2-1.8, and it is more preferable that it is 1.35-1.65. When the absolute refractive index of the constituent material of the member 7 with the recesses is a value within the above range, the above-described effect is exhibited more significantly.
Further, when the absolute refractive index of the constituent material (solidified material) of the substrate body 2 is n ₁ and the absolute refractive index of the constituent material of the member 7 with recesses is n ₂ , 0.01 <n ₁ −n ₂ <0.8 is preferable, 0.02 <n ₁ −n ₂ <0.4 is preferable, and 0.03 <n ₁ −n ₂ <0.25. It is preferable to satisfy By satisfying such a relationship, as will be described in detail later, it is possible to irradiate the photopolymer 32 with light having an optimum light intensity distribution, thereby more efficiently opening the opening 31 having the optimum size. Can be formed.

  The member with recesses (member with recesses for forming microlenses) 7 includes a plurality of recesses (recesses for forming microlenses) 71 arranged in a manner corresponding to the arrangement method of the microlenses 21 (transferred positional relationship). ing. These recesses 71 have a shape corresponding to the microlens 21 (substantially the same shape except for the transferred shape) and dimensions, except that the microlens 21 is a protrusion while the microlens 21 is a protrusion. have.

  More specifically, in the present embodiment, the recess (microlens formation recess) 71 has a vertical width (width in the vertical direction) smaller than a horizontal width (width in the horizontal direction) when the member with recess 7 is viewed in plan. It has a flat shape (substantially oval or substantially bowl-shaped). By using the recess 71 having such a shape, it can be suitably used for manufacturing the microlens substrate 1 that can effectively prevent the occurrence of inconvenience such as moire and can have particularly excellent viewing angle characteristics. Can do.

Further, when the length in the minor axis direction (longitudinal direction) of the recess 71 when viewed in plan is L ₁ [μm] and the length in the major axis direction (lateral direction) is L ₂ [μm], 0.50 ≦ L ₁ / L ₂ ≦ 0.99 is preferably satisfied, 0.60 ≦ L ₁ / L ₂ ≦ 0.90 is more preferable, and 0.65 ≦ L ₁ / L _It is more preferable to satisfy the relationship of ₂ ≦ 0.80. By satisfying the relationship as described above, the effects as described above become more remarkable.

  Moreover, it is preferable that the length of the short axis direction of the recessed part 71 when it planarly views is 10-200 micrometers, It is more preferable that it is 30-150 micrometers, It is further more preferable that it is 50-100 micrometers. When the length of the concave portion 71 in the short axis direction is a value within the above range, the viewing angle characteristics of the manufactured microlens substrate 1 and the contrast and brightness of the image projected by the microlens substrate 1 are particularly excellent. However, sufficient resolution can be obtained in the projected image. Further, when the length of the concave portion 71 in the minor axis direction is a value within the above range, it is possible to effectively prevent the occurrence of inconvenience such as moire when the manufactured microlens substrate 1 is used. The productivity of the microlens substrate 1 (the member 7 with the recesses) can be further increased.

  Further, the length in the major axis direction of the recess 71 when seen in a plan view is preferably 15 to 250 μm, more preferably 45 to 200 μm, and even more preferably 70 to 150 μm. When the length of the concave portion 71 in the major axis direction is within the above range, the viewing angle characteristics of the manufactured microlens substrate 1 and the contrast and brightness of the image projected by the microlens substrate 1 are particularly excellent. However, sufficient resolution can be obtained in the projected image. Further, when the length of the concave portion 71 in the major axis direction is within the above range, it is possible to effectively prevent the occurrence of inconvenience such as moire when the manufactured microlens substrate 1 is used. The productivity of the microlens substrate 1 (the member 7 with the recesses) can be further increased.

  Moreover, it is preferable that the curvature radius of the recessed part 71 is 7.5-375 micrometers, It is more preferable that it is 30-180 micrometers, It is further more preferable that it is 70-120 micrometers. When the radius of curvature of the recess 71 is a value within the above range, the viewing angle characteristics of the manufactured microlens substrate 1 can be made particularly excellent. In particular, both the horizontal and vertical viewing angle characteristics can be improved. The concave portion 71 may have a different radius of curvature in the minor axis direction and a radius of curvature in the major axis direction. In such a case, the radius of curvature in the major axis direction is a value within the above range. Preferably there is.

Moreover, it is preferable that the depth of the recessed part 71 is 7.5-375 micrometers, It is more preferable that it is 30-180 micrometers, It is further more preferable that it is 70-120 micrometers. When the depth of the recess 71 is a value within the above range, the viewing angle characteristics of the manufactured microlens substrate 1 can be made particularly excellent.
The plurality of recesses 71 are arranged in a staggered pattern (in a staggered pattern). By arranging the recesses 71 in this way, it is possible to effectively prevent the occurrence of inconvenience such as moire when the manufactured microlens substrate 1 is used. On the other hand, for example, if the concave portions are arranged in a square lattice shape or the like, it is difficult to sufficiently prevent the occurrence of inconvenience such as moire depending on the size of the concave portions (microlenses). In addition, when the concave portions are randomly arranged, depending on the size of the concave portion (microlens) or the like, it becomes difficult to sufficiently increase the occupancy ratio of the concave portions in the effective region where the concave portions are formed. It is difficult to sufficiently increase the transmittance (light utilization efficiency), and the obtained image may be dark.

  In addition, as described above, the recesses 71 are arranged in a staggered pattern when the member 7 with recesses is viewed in plan, and are adjacent to the first row composed of the plurality of recesses 71. It is preferable that the second row is shifted by a half pitch in the vertical direction (the short axis direction of the recess 71). As a result, when the manufactured microlens substrate 1 is used, it is possible to more effectively prevent the occurrence of moiré due to light interference and to make the viewing angle characteristics particularly excellent. it can.

  Moreover, the member 7 with a recessed part may be provided with the mold release process part formed by the mold release process in the surface side in which the recessed part 71 was provided. Thereby, in the manufacturing method of the microlens substrate 1 described in detail later, when the substrate body 2 is removed from the member 7 with the recess, the lens surface side light-shielding portion 4 provided to the member 7 with the recess is removed from the member 7 with the recess. It is possible to transfer more reliably to the main body 2 side. In addition, when the mold release processing unit is provided, in the manufacturing method of the microlens substrate 1 described in detail later, the lens is sufficiently prevented from causing defects such as chipping in the microlens 21 included in the substrate body 2. The recessed member 7 can be easily removed from the substrate body 2 provided with the surface-side light-shielding portion 4, and as a result, defects in the microlens 21 can be prevented in the final microlens substrate 1.

In the above description, the concave portion 71 is described as having substantially the same shape (dimension) and arrangement method as the microlens 21 except that the concave portion 71 has a concave-convex relationship. In the case where the constituent material of the substrate body 2 is easy to shrink (when the composition constituting the substrate body 2 shrinks due to solidification or the like) You may make it a shape (dimension), an occupation rate, etc. differ among these.
Next, the manufacturing method of a member with a recessed part is demonstrated, referring FIG. In practice, a large number of recesses (microlens formation recesses) are formed on the substrate. Here, in order to make the description easy to understand, a part of them is shown highlighted.

<A1> First, when manufacturing the member 7 with concave portions, a substrate 70 is prepared (see FIG. 5A).
As the substrate 70, a substrate having a uniform thickness and having no deflection or scratch is preferably used. The substrate 70 preferably has a surface cleaned by cleaning or the like.
Further, the substrate 70 may be colored, for example, near the surface on the side where the recess 71 is formed. Thereby, in the member 7 with a recessed part manufactured, the flat part 79 (site | part which is not etched) can be identified easily. As a result, in the method of manufacturing the microlens substrate 1 using the recessed member 7 described in detail later, the light shielding material can be efficiently and selectively applied to the flat portion 79. Productivity is improved.

<A2> A mask 8 having a large number of initial holes (openings) 81 is formed on the surface of the prepared substrate 70, and the back surface of the substrate 70 (the surface opposite to the surface on which the mask 8 is formed) A protective film 89 is formed (see a masking step, FIG. 5B and FIG. 5C).
In particular, in this embodiment, first, as shown in FIG. 5B, a back surface protective film 89 is formed on the back surface of the prepared substrate 70, and a mask forming film 80 is formed on the surface of the substrate 70 (mask). (Formation film forming step) Then, as shown in FIG. 5C, the mask 8 is obtained by forming the initial hole 81 in the mask formation film 80 (initial hole formation step). The mask forming film 80 and the back surface protective film 89 can be formed simultaneously.

  The mask forming film 80 is preferably capable of forming an initial hole 81 to be described later by laser light irradiation or the like and having resistance to etching in an etching process to be described later. In other words, the mask forming film 80 (mask 8) is preferably configured so that the etching rate is substantially equal to or lower than that of the substrate 70.

From this point of view, the material forming the mask forming film 80 (mask 8) is, for example, a metal such as Cr, Au, Ni, Ti, or Pt, an alloy containing two or more selected from these metals, Examples thereof include oxides (metal oxides), silicon, and resins.
Further, the mask forming film 80 (mask 8) may have, for example, a substantially uniform composition, or a laminated body having a plurality of different layers.

  As described above, the configuration of the mask forming film 80 (mask 8) is not particularly limited. However, the mask forming film 80 (mask 8) is a laminate including a layer mainly composed of chromium and a layer mainly composed of chromium oxide. Preferably there is. The mask forming film 80 having such a configuration can easily and surely form an opening having a desired shape by irradiation of laser light as described later. The mask 8 obtained by using the mask forming film 80 has excellent stability with respect to etching solutions having various compositions (the substrate 70 can be more reliably protected in the etching process described later). . Further, when the substrate 70 is made of a glass material and the mask forming film 80 (mask 8) has the above structure, for example, in an etching process described later, one hydrogen as an etchant is used. A liquid containing ammonium difluoride can be suitably used. Since ammonium monohydrogen difluoride is not a poisonous deleterious substance, it is possible to prevent the human body and the environment during work more reliably. Further, the mask forming film 80 (mask 8) having the above-described configuration can relieve the internal stress of the mask efficiently, and is particularly excellent in adhesion with the substrate 70 (particularly adhesion in the etching process). ing. For this reason, by using the mask forming film 80 (mask 8) having the above-described configuration, the concave portion 71 having a desired shape can be easily and reliably formed.

  The method for forming the mask forming film 80 is not particularly limited, but the mask forming film 80 (mask 8) is made of a metal material (including an alloy) such as chromium (Cr) or gold (Au) or a metal oxide (for example, chromium oxide). ), Or a composite material thereof (for example, a laminated body having a metal layer made of a metal material and a metal oxide layer made of a metal oxide, etc.) The film 80 can be suitably formed by, for example, a vapor deposition method or a sputtering method. When the mask forming film 80 (mask 8) is made of silicon, the mask forming film 80 can be suitably formed by, for example, a sputtering method or a CVD method.

  The thickness of the mask forming film 80 (mask 8) varies depending on the material constituting the mask forming film 80 (mask 8), but is preferably about 0.01 to 2.0 μm, preferably 0.01 to 0.3 μm. The degree is more preferable. If the thickness is less than the lower limit, the shape of the initial hole 81 formed in the initial hole forming step (opening forming step) described later may be distorted depending on the constituent material of the mask forming film 80 and the like. There is. In addition, when wet etching is performed in an etching process described later, the masked portion of the substrate 70 may not be sufficiently protected. On the other hand, if the upper limit value is exceeded, depending on the constituent material of the mask forming film 80, it becomes difficult to form the initial hole 81 that penetrates in the initial hole forming step described later, and the mask forming film 80 (mask Due to the internal stress of 8), the mask forming film 80 (mask 8) may be easily peeled off.

  The back surface protective film 89 is for protecting the back surface of the substrate 70 in the subsequent steps. By this back surface protective film 89, erosion, deterioration, etc. of the back surface of the substrate 70 are suitably prevented. This back surface protective film 89 has the same configuration as the mask forming film 80 (mask 8), for example. Therefore, the back surface protective film 89 can be provided in the same manner as the mask forming film 80 simultaneously with the formation of the mask forming film 80.

<A3> Next, as shown in FIG. 5C, a plurality of initial holes (openings) 81 are formed in the mask forming film 80 to obtain the mask 8 (initial hole forming step). The initial hole 81 formed in this step functions as a mask opening in the later-described etching.
A method for forming the initial hole 81 is not particularly limited, but a method using laser light irradiation is preferable. Thereby, the initial holes 81 having a desired shape arranged in a desired pattern can be easily and accurately formed. As a result, the shape, arrangement method, and the like of the recesses 71 can be controlled more reliably. In addition, by forming the initial hole 81 by laser irradiation, a member with a recess can be manufactured with high productivity. In particular, the concave portion can be easily formed even on a large-area substrate. In addition, by forming the initial hole 81 in the mask forming film 80 by laser light irradiation, the opening (e.g., easier and less expensive than the case where the opening is formed in the resist film by a photolithography method as in the prior art. An initial hole 81) can be formed.

In addition, when the initial hole 81 is formed by laser light irradiation, the type of laser light to be used is not particularly limited, but a ruby laser, a semiconductor laser, a YAG laser, a femtosecond laser, a glass laser, a YVO ₄ laser, a Ne- He laser, Ar laser, CO ₂ laser, excimer laser or the like may be mentioned. Moreover, you may use wavelengths, such as SHG of each laser, THG, and FHG.

  The shape and size of the initial hole 81 formed in this step is not particularly limited, but is substantially circular and the diameter is preferably 0.5 to 30 μm, more preferably 1.0 to 10 μm. Preferably, it is 1.5-5 micrometers. When the diameter of the initial hole 81 is a value within the above range, the concave portion 71 having the above-described shape can be reliably formed in the etching process described later. However, when the initial hole 81 has a flat shape such as a substantially elliptical shape, the length in the minor axis direction can be substituted for the value of the diameter. That is, when the initial hole 81 formed in this step has a flat shape, the width of the initial hole 81 (length in the minor axis direction) is not particularly limited, but is preferably 0.8 to 30 μm, More preferably, it is 1.0-10 micrometers, and it is still more preferable that it is 1.5-5 micrometers. When the width of the initial hole 81 is a value within the above range, the concave portion 71 having the above-described shape can be reliably formed in the etching process described later.

  In addition, when the initial hole 81 formed in this step is a flat shape, the length of the initial hole 81 (length in the major axis direction) is preferably 0.5 to 30 μm, and 1.0 to More preferably, it is 15 micrometers, and it is still more preferable that it is 1.5-10 micrometers. When the length of the initial hole 81 is a value within the above range, the concave portion 71 having the above-described shape can be more reliably formed in the etching process described later.

<A4> Next, as shown in FIG. 5D, the substrate 70 is etched using the mask 8 in which the initial holes 81 are formed, and a large number of recesses 71 are formed on the substrate 70 (etching step). .
The etching method is not particularly limited, and examples thereof include wet etching and dry etching. In the following description, a case where wet etching is used will be described as an example.

By performing etching (wet etching) on the substrate 70 covered with the mask 8 in which the initial holes 81 are formed, as shown in FIG. 5D, the substrate 70 has a portion where the mask 8 does not exist ( A large number of recesses 71 are formed on the substrate 70 by etching from a portion corresponding to the initial hole 81 of the mask 8. As described above, since the initial holes 81 formed in the mask 8 are arranged in a staggered pattern (in a staggered pattern), the formed recesses 71 are formed in a staggered pattern (in a staggered pattern) on the surface of the substrate 70. It will be arranged.
Further, when the wet etching method is used, the concave portion 71 can be suitably formed. For example, when an etchant containing ammonium monohydrogen difluoride is used as the etchant, the substrate 70 can be etched more selectively, and the recesses 71 can be suitably formed.

In the case where the mask 8 (mask forming film 80) is mainly composed of chromium or chromium oxide, a liquid containing ammonium monohydrogen difluoride is particularly suitable as the hydrofluoric acid-based etching solution. Since the ammonium hydrogen difluoride solution is not a poisonous and deleterious substance, it can prevent the influence on the human body and the environment during work. When ammonium monohydrogen difluoride is used as the etching solution, the etching solution may contain, for example, hydrogen peroxide and / or sulfuric acid. Thereby, an etching speed can be made faster.
Further, according to wet etching, it is possible to perform processing with a simpler apparatus than dry etching, and it is possible to perform processing on many substrates at once. Thereby, productivity improves and the member 7 with a recessed part can be provided cheaply.

<A5> Next, as shown in FIG. 5E, the mask 8 is removed (mask removal step). At this time, the back surface protective film 89 is also removed together with the removal of the mask 8.
When the mask 8 is a laminated body having a layer mainly composed of chromium and a layer mainly composed of chromium oxide as described above, the removal of the mask 8 is, for example, ceric ammonium nitrate and perchlorine. It can carry out suitably by etching using a mixture containing an acid.

As described above, as shown in FIG. 4, the concave member 7 in which a large number of concave portions 71 are formed in a staggered pattern on the substrate 70 is obtained.
The method for forming the plurality of recesses 71 arranged in a staggered pattern on the substrate 70 is not particularly limited. However, the method described above (the initial holes 81 in the mask forming film 80 by irradiation with laser light). To obtain the mask 8, and then etching using the mask 8 to form the recess 71 on the substrate 70), the following effects are obtained.

That is, by forming the initial holes 81 in the mask forming film 80 by laser light irradiation, the openings (with a predetermined pattern) can be easily and inexpensively compared to the case where the openings are formed by a conventional photolithography method. A mask having initial holes 81) can be obtained. Thereby, productivity improves and the member 7 with a recessed part can be provided cheaply.
Further, according to the method as described above, it is possible to easily perform processing on a large substrate. When manufacturing a large substrate (a member with a recess, a lens substrate), it is not necessary to bond a plurality of substrates as in the prior art, and the seam of bonding can be eliminated. As a result, a high-quality large-sized substrate (a member with a recess, a lens substrate) can be manufactured at a low cost by a simple method.

Further, when the initial holes 81 are formed by laser irradiation, the shape, size, arrangement, and the like of the formed initial holes 81 can be managed easily and reliably.
In addition, you may perform a mold release process with respect to the member 7 with a recessed part, for example in order to form the mold release process part as mentioned above. As the mold release treatment, for example, formation of a film composed of a material having releasability such as silicone resin such as alkylpolysiloxane, fluorine resin such as polytetrafluoroethylene, hexamethyldisilazane ([(CH _{3) 3 Si]} 2 NH) surface treatment with a silylating agent such as a surface treatment or the like with a fluorine gas.

  By the way, since the member 7 with a recessed part obtained as mentioned above has many recessed parts 71, the target recessed part may not be formed in the site | part which should form the recessed part 71. FIG. That is, there is a case where the concave portion 71 is not provided at a portion where the concave portion 71 is to be provided, or a concave portion 71 ′ smaller than the concave portion 71 to be formed is formed. In such a case, a flat portion 79 having a predetermined size or more exists at or around the site as described above. And when such a flat part 79 exists, the board | substrate body 2 manufactured using the member 7 with a recessed part will have the flat part 28 in a corresponding site | part. When the microlens substrate (lens substrate) 1 includes the substrate body 2 having the flat portion 28 as described above, the light incident side (surface on which the microlens (convex lens) 21 of the substrate body 2 is provided). When the light (incident light) is incident on the flat portion 28 from the side), the flat portion 28 does not have a condensing function like the lens portion. On the transmissive screen 10), it is recognized as a bright spot and has a significant adverse effect on the displayed image. The above-mentioned defects are caused by, for example, in the manufacture of a member with a recess, the initial hole cannot be reliably formed in a portion where the initial hole of the mask forming film is to be formed, or the mask is formed during etching. This occurs when dirt adheres to the vicinity of the initial hole. Although it is possible to try to suppress the occurrence of defects as described above by optimizing mask formation conditions and etching conditions, it is used for manufacturing a large lens substrate (for example, a lens substrate having a diagonal length of 100 cm or more). In a member with a recess, it is extremely difficult to completely prevent the occurrence of defects as described above.

Therefore, in the present invention, when the above-described defect exists in the member with the concave portion, by providing a light-shielding material to the corresponding part, in the final lens substrate, the lens surface side corresponding to the substrate main body is dealt with. The lens surface side light-shielding part made of a light-shielding material is provided at the site, and it is characterized in that it has been found that the above problems can be solved.
Further, the reason why the “flat portion having a predetermined size or more” is formed is not only based on the above-described defects during manufacturing, but also for the purpose of improving the optical characteristics of the lens substrate, and so on. The case where a site | part is provided, the case where a smaller lens is formed, etc. are mentioned.
Hereinafter, a method for manufacturing the microlens substrate (lens substrate) 1 using the above-described member 7 with a recess will be described.

<B1> First, the member 7 with a recess is prepared (member preparing step with a recess; see FIG. 6A), and the surface of the member 7 with the recess on the side where the recess 71 is formed is flat with a predetermined size or more. Whether or not the portion 79 exists is inspected, and a light-shielding material is applied to the detected flat portion 79 to form the lens surface side light-shielding portion 4 (light-shielding material applying step, FIG. 6B). )reference).
Various methods can be used as a method for inspecting the presence of the flat portion 79 (a method for detecting the flat portion 79), and is not particularly limited. For example, the following method is applied. be able to.

That is, the presence or absence of the flat portion 79 can be inspected by directly observing the patterning (uneven shape) of the surface of the member 7 with the recess with a camera or the like.
Moreover, since the depth of a recessed part and height differ in the part of the flat part 79, and the part other than that, the flat part 79 is detectable by measuring a level | step difference.
Further, as described above, when the member 7 with concave portions has a colored portion (colored portion) in the vicinity of the surface, the flat portion 79 can be easily and reliably identified.

Further, since the amount of transmitted light is different between the flat portion 79 and other portions, light is projected from the back surface of the member 7 with the recesses, the transmitted light is detected, and the difference in the amount of light (for example, bright spots) The presence / absence of the flat portion 79 can be inspected by detecting the presence / absence (white dot) (same as the presence / absence of scattering of the projection light).
When the above method is employed, for example, an inspection apparatus as shown in FIG. 8 can be suitably used.

  The inspection apparatus 120 shown in FIG. 8 includes a moving stage 122 installed in parallel to the main surface of the member 7 with a recess, and a CCD camera 121 movably mounted or suspended on the moving stage 122. . When the flat part 79 is detected by measuring the amount of light transmitted through the member 7 with a recess, the inspection device 120 is parallel to the member 7 with a recess from the side opposite to the side where the CCD camera 121 is installed. It has light irradiation means (not shown) for irradiating light.

In this inspection apparatus 120, the CCD camera 121 scans the entire surface of the member 7 with a recess (an effective area where the recess is formed). Then, the inspection signal obtained by scanning is input to the image processing device 123, and image processing is performed to detect the flat portion 79. If detected, the position information is stored in a storage means (not shown).
And if the flat part 79 is detected, the lens surface side light-shielding part 4 will be formed by providing a light-shielding material to this location. The application of the light shielding material can be performed based on position information obtained by scanning with the CCD camera 121.

  Application of the light-shielding material (formation of the lens-surface-side light-shielding portion 4 to the member 7 with a recess) is not particularly limited, and examples thereof include roller coating and an ink jet method. By applying a light shielding material by roller application, the lens surface side light shielding portion 4 can be formed efficiently. In general, the depth (height) is different between the flat portion 79 and other portions, and the flat portion 79 often protrudes compared to other portions. For example, the light shielding material can be selectively and easily applied to the flat portion 79 at the top of the protruding portion (the flat portion 79 as the top of the convex portion having a predetermined height or more). Therefore, even if the accuracy of the positional information of the flat portion 79 obtained by the inspection apparatus 120 is relatively low, a light shielding material can be selectively applied to the flat portion 79. Even if the process of detecting the flat portion 79 is simplified or omitted, the light shielding material can be selectively applied to the flat portion 79 as described above. In addition, when the ink jet method is employed, even when the flat portion 79 is relatively small, a light shielding material can be selectively applied to a desired portion. In addition, when the ink jet method is employed, the ratio of the surface area to the volume of the light-shielding material to be used is high, so the content of the solvent (including the dispersion medium, etc.) in the light-shielding material to be applied is relatively high Even so, most of the solvent is removed shortly after the droplets of the light-shielding material are discharged. Therefore, even when a light shielding material having a relatively high solvent content is used, the lens surface side light shielding portion 4 can be efficiently formed. In addition, since most of the solvent is removed in a relatively short time as described above, even if the light-shielding material is repeatedly applied to the same part in a relatively short time, the formed light shielding on the lens surface side is formed. It is difficult for the portion 4 to be deformed. For this reason, even if the lens surface side light shielding part 4 to be formed is relatively thick, the lens surface side light shielding part 4 can be formed easily and reliably in a relatively short time.

The thickness of the light-shielding material applied to the flat portion 79 is preferably 0.01 to 5 μm, and more preferably 0.01 to 2 μm. By setting the thickness of the light-shielding material to a value within the above range, in the final microlens substrate 1, the lens surface side light-shielding portion 4 is particularly excellent while having sufficiently high adhesion to the substrate body 2. The light shielding property can be exhibited.
The light-shielding material may be any material as long as it can exhibit light-shielding properties when constituting the lens surface side light-shielding portion 4 in the final microlens substrate 1. It contains colorants such as various pigments.

The light-shielding material may include a solvent (including a solvent, a dispersion medium, and the like), a binder resin, and the like. Thereby, the handleability (easy handling) of the light-shielding material is improved, and the light-shielding material application step can be performed efficiently.
As the solvent, for example, water or various organic solvents can be applied. Examples of the organic solvent include propylene glycol monomethyl ether acetate, propylene glycol monopropyl ether, methoxymethyl propionate, ethoxyethyl propionate, ethyl lactate, ethyl pyruvate, methyl amyl ketone, cyclohexanone, xylene, toluene, butyl acetate. Etc., and one or more of these can be used in combination.

  Examples of the binder resin include polystyrene, poly-α-methylstyrene, chloropolystyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, and styrene-vinyl chloride copolymer. Styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, styrene-acrylic acid ester copolymer, styrene-acrylic copolymer, styrene-methacrylic acid ester copolymer, styrene-acrylic acid ester-methacrylic acid A styrene resin such as an ester copolymer, a styrene-α-chloromethyl acrylate copolymer, a styrene-acrylonitrile-acrylic acid ester copolymer, a styrene-vinyl methyl ether copolymer, or the like containing a styrene or a styrene substitution product. Polymer or copolymer, Reester resin, epoxy resin, urethane modified epoxy resin, silicone modified epoxy resin, vinyl chloride resin, rosin modified maleic acid resin, phenyl resin, polyethylene, polypropylene, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-ethyl acrylate A copolymer, a xylene resin, a polyvinyl butyral resin, a terpene resin, a phenol resin, an aliphatic or alicyclic hydrocarbon resin, and the like can be given, and one or more of these can be used in combination.

The light-shielding material includes, for example, a water-soluble polymer such as sodium alginate, a water-soluble resin, a fluorosurfactant, an antiseptic, an antifungal agent, a rust preventive, a dissolution aid, an antioxidant, and the like. There may be.
Examples of antiseptics and antifungal agents include sodium benzoate, sodium pentachlorophenol, sodium 2-pyridinethiol-1-oxide, sodium sorbate, sodium dehydroacetate, 1,2-dibenzisothiazolin-3-one (Proxel CRL, Proxel BDN, Proxel GXL, Proxel XL-2, Proxel TN (trade name) manufactured by AVECIA) and the like.

  Examples of the dissolution aid and antioxidant include metal hydroxides such as potassium hydroxide, sodium hydroxide and lithium hydroxide, ammonium salts such as ammonium hydroxide and quaternary ammonium hydroxide (tetramethylammonium, etc.). , Carbonates such as potassium carbonate, sodium carbonate, lithium carbonate and other phosphates, ureas such as urea, thiourea and tetramethylurea, allophanates such as allophanate and methylallohanate, biuret, dimethylbiuret and tetramethylbiuret And biurets.

Although the lens surface side light-shielding part 4 should just have light-shielding property, it is preferable that the color is black. Thereby, the light-shielding property by the lens surface side light-shielding part 4 becomes especially excellent, and the contrast of the displayed image can be made particularly excellent.
The content of the colorant (dye or pigment) in the light-shielding material is preferably 0.5 to 20% by weight, and more preferably 1.0 to 15% by weight. When the content of the colorant in the light shielding material is a value within the above range, the lens surface side light shielding portion 4 having sufficient light shielding properties can be formed, and the viscosity, surface tension, etc. of the light shielding material can be adjusted. It can be made suitable easily, the handleability of the light-shielding material is improved, and the light-shielding material application step can be performed efficiently.

It should be noted that the light-shielding material is applied as necessary (for example, when the area where the light-shielding material is to be applied is relatively large, or when the thickness of the lens-surface-side light-shielding portion 4 to be formed is relatively thick, etc. May be repeated a plurality of times.
Further, after the application of the light-shielding material, a heat treatment such as heating or cooling, a pressurization of the atmosphere, or a pressure reduction may be performed as necessary. Thereby, for example, the stability of the shape of the lens-surface-side light-shielding portion 4 is improved, and the lens-surface-side light-shielding portion 4 can be more reliably transferred to the substrate body 2 in a process (transfer process) described later. The shape of the lens surface side light-shielding portion 4 in the final microlens substrate 1 can be made more suitable.

  <B2> Next, as shown in FIG. 6C, on the surface of the member 7 with the recesses on the side where the recesses 71 are formed, the composition 23 having fluidity (for example, a softened resin material, An unpolymerized (uncured resin material) is applied (composition applying step), and a base film 24 is placed thereon, and the composition 23 is flattened (pressing member) 11 via the base film 24. (Pressing process).

  The base film 24 is preferably made of a material having a refractive index comparable to that of the composition 23 (the composition 23 after solidification). More specifically, the base film 24 is an absolute constituent material of the base film 24. The absolute value of the difference between the refractive index and the absolute refractive index of the composition 23 after solidification is preferably 0.20 or less, more preferably 0.10 or less, and 0.02 or less. Further preferred. The base film 24 may be made of any material, but is preferably made of polyethylene terephthalate. In addition, the base film 24 may be a relatively thick film or a film that is not substantially flexible.

  In addition, you may perform the press by the flat plate 11 in the state which has arrange | positioned the spacer between the member 7 with a recessed part, and the base film 24, for example. Thereby, the thickness of the board | substrate body 2 formed can be controlled more reliably. Moreover, when using a spacer, when solidifying the composition 23, the spacer should just be distribute | arranged between the member 7 with a recessed part, and the base film 24, and the timing which supplies a spacer is not specifically limited. For example, the composition 23 in which spacers are dispersed in advance as a resin to be applied may be used on the surface of the member 7 with recesses on the side where the recesses 71 are formed, or the spacers are arranged on the member 7 with recesses. The composition 23 may be applied, or a spacer may be applied after the composition 23 is supplied.

In the case of using a spacer, the spacer is preferably made of a material having a refractive index comparable to that of the solidified composition 23, and more specifically, the absolute refractive index of the constituent material of the spacer and the solidified material. The absolute value of the difference from the absolute refractive index of the composition 23 is preferably 0.20 or less, more preferably 0.10 or less, still more preferably 0.02 or less, and after solidification The composition 23 and the spacer are most preferably composed of the same material.
The shape of the spacer is not particularly limited, but is preferably substantially spherical or substantially cylindrical. When the spacer has such a shape, the diameter thereof is preferably 10 to 300 μm, more preferably 30 to 200 μm, and further preferably 30 to 170 μm.

  <B3> Next, the composition 23 is solidified (including curing (polymerization)) to obtain the substrate body 2 provided with the microlenses 21 corresponding to the recesses 71 (solidification step; see FIG. 6D). . In the present embodiment, the substrate body 2 is obtained as a bonded body of the solidified composition 23 and the base film 24. Further, the obtained substrate body 2 is in contact with the lens surface side light-shielding portion 4 on the surface of the flat portion 28.

In the case where the composition 23 is solidified by curing (polymerization), examples of the method include methods such as irradiation with light such as ultraviolet rays, irradiation with electron beams, and heating.
Here, if necessary, in the composition 23 and / or the base film 24, for example, polystyrene beads, glass beads, organic cross-linked polymers, etc. are used as a diffusing material in advance in order to diffuse the incident light from the light source. May be mixed. Here, the diffusing material may be mixed in the composition 23 and / or the entire base film 24, or may be mixed only in part.

  <B4> Next, the flat plate 11 is removed from the formed substrate body 2 (pressing member removing step, see FIG. 6E). At this time, the member 7 with the recess is not removed but is kept in close contact with the substrate body 2. The removed flat plate 11 can be used repeatedly for the manufacture of the substrate body 2 (microlens substrate 1), thereby improving the manufacturing cost and the stability of the quality of the manufactured substrate body 2 (microlens substrate 1). Is advantageous.

<B5> Next, a black matrix (light-shielding film) 3 is formed on the exit-side surface of the substrate body 2 manufactured as described above.
In this embodiment, the light shielding film is formed by performing a process of applying a light shielding film forming material to the substrate body (light shielding film forming material application process) and a process of irradiating the light shielding film forming material with light. Through the step of forming the opening (opening forming step). The light shielding film forming material may be any material as long as it can form an opening, but preferably contains a photosensitive component. Thereby, the opening part of a suitable shape can be formed easily and reliably. In the following description, it is assumed that a positive photopolymer 32 is mainly used as a light shielding film forming material.

  First, as shown in FIG. 7 (f), a positive photopolymer (light shielding film forming material) 32 having light shielding properties is applied to the light exiting surface of the substrate body 2 (light shielding film forming material applying step). . As a method for applying the photopolymer 32 to the surface of the substrate body 2, for example, various coating methods such as dip coating, doctor blade, spin coating, brush coating, spray coating, electrostatic coating, electrodeposition coating, roll coater, etc. are used. be able to. The photopolymer 32 may be composed of a resin having a light shielding property, or may be a resin material (low light shielding property) dispersed or dissolved in a light shielding material. After application of the photopolymer 32, heat treatment such as pre-baking treatment may be performed as necessary.

<B6> Next, the substrate main body 2 is irradiated with light (exposure light) Lb through the member 7 with concave portions.
The irradiated light (exposure light) Lb is refracted and collected by entering the microlens 21. Then, by being condensed, the photopolymer 32 in the portion irradiated with the light having an increased luminous intensity (light beam) is exposed, and the other portion of the photopolymer 32 is not exposed or the exposure amount is reduced. Only the photopolymer 32 in the portion irradiated with light having an increased luminous intensity (light flux) is exposed.

  The light (exposure light) Lb applied to the substrate body 2 is not particularly limited, but is preferably parallel light. As a result, the size of the opening 31 to be formed can be controlled more reliably, and as a result, the viewing angle characteristics and the light utilization efficiency of the microlens substrate 1 should be particularly excellent. And the contrast of the projected image can be made higher.

  Here, on the flat part (the flat part 79 between the adjacent concave part 71 and the concave part 71 and the flat part 28 between the adjacent microlens 21 and the microlens 21), the lens surface side light-shielding part 4 is provided. It has been. For this reason, the light incident on the part corresponding to the flat part (flat part 79, flat part 28) is blocked by the lens surface side light-shielding part 4 and the part corresponding to the flat part (flat part 79, flat part 28). It is possible to effectively prevent the light shielding film forming material (photopolymer) 32 from being exposed. Therefore, the condensing part of the microlens 21 can be selectively exposed and the other parts can be effectively prevented from being exposed. As a result, it is possible to effectively prevent the condensing part of the microlens 21 from selectively forming the opening 31 and forming the opening 31 in other parts.

In this embodiment, the substrate body 2 is irradiated with light through the member 7 with a recess. And in this embodiment, the member 7 with a recessed part has a refractive index (absolute refractive index) larger than various gases (for example, air, various inert gases, etc.), and the constituent material of the base-material main body 2 It is comprised with the material which has a refractive index (absolute refractive index) smaller than (the constituent material of the solidified state). As a result, as shown in FIG. 9, light with a sufficient luminous intensity (light flux) in a wider area (than the luminous intensity Z ₀ necessary for exposure) compared to the case where light is irradiated with the member 7 having the recesses removed. Can be irradiated. Also, when the exposure process is performed with the recessed member 7 removed by performing the process of exposing the light shielding film forming material (photopolymer) 32 with the recessed member 7 attached to the substrate body 2. As compared with the above, variation in luminous intensity (light flux) (difference between the maximum value and the minimum value) in the region irradiated with refracted light can be reduced. For this reason, the energy of light can be efficiently used for the exposure of the light shielding film forming material (photopolymer) 32, and the energy can be effectively used. For this reason, the black matrix 3 having the optimal size (sufficient size) opening 31 and the black matrix 3 having the optimal aperture ratio can be formed more efficiently. In addition, light having a small variation in luminous intensity (light flux) (difference between the maximum value and the minimum value) can be irradiated to a portion to be an opening (non-light-shielding portion) of the light-shielding film forming material (photopolymer). Therefore, it is possible to effectively prevent partial irradiation with light having a greater luminous intensity (light flux) than necessary. Thereby, generation | occurrence | production of problems, such as deterioration of the constituent material of the board | substrate body 2, can be prevented effectively. Moreover, in this embodiment, since the member with a recess is removed in a later step, the refractive index of light can be increased in the final microlens substrate 1, and as a result, the viewing angle characteristics are particularly excellent. can do. Further, as described above, by performing the process of exposing the light-shielding film forming material (photopolymer) 32 with the recessed member 7 attached, for example, when the thickness of the substrate body 2 is relatively thin, etc. In this case, the stability of the shape of the substrate body 2 when the black matrix 3 is formed can be made excellent. This makes it possible to more reliably form the black matrix 3 having the opening 31 having a desired size at a desired portion, and as a result, the optical characteristics of the microlens substrate 1 finally obtained are particularly excellent. It can be.

  Development is performed after the light Lb is irradiated by the method as described above. Here, since the photopolymer 32 is a positive type photopolymer, the photopolymer 32 in the exposed portion (the portion irradiated with the condensed light) is dissolved and removed by development. As a result, as shown in FIG. 7G, the black matrix 3 in which the openings 31 are formed is formed (opening forming step). The development method varies depending on the composition of the photopolymer 32 and the like, but can be performed using, for example, an alkaline solution such as a KOH aqueous solution.

  As described above, the photopolymer is irradiated with light (exposure light) condensed by a microlens to form a black matrix (light-shielding film having an opening), for example, compared to using photolithography technology. Thus, the black matrix can be formed by a simple process.

In addition, you may perform heat processing, such as a post-baking process after development, as needed.
In the above description, the light shielding film (black matrix 3) is formed using a positive photopolymer as the light shielding film forming material (in <B5> and <B6>). Materials other than polymers may be used. For example, a reversal developing material such as a silver salt photosensitive material may be used as the light shielding film forming material. When a silver salt photosensitive material (reversal developing material) is used, after exposure as described above, once the exposed portion is processed to be desalted, and then further exposed and developed. The first exposed portion can be a light transmissive non-light-shielding portion, and the other portions can be light-shielding portions (light-shielding regions). In addition, a photosensitive material may not be used for forming the light shielding film. For example, after a film made of a material for forming a light-shielding film other than a photosensitive material is formed on the substrate body, it is condensed by the lens unit by irradiating light (energy rays), and the energy density is increased. The light shielding film having the opening may be formed by blowing off a part of the film made of the material for forming the light shielding film or evaporating the light. That is, in the above description, it has been described that the exposure process and the development process are performed in the opening forming process, but the opening forming process may not perform such a plurality of processes.

Further, a series of processes such as application of the light shielding film forming material and light irradiation (exposure) as described above may be repeated. Thereby, the light shielding film (black matrix) can be formed thicker, and the contrast can be further improved.
In the above description, the light shielding film forming material (photopolymer) is directly applied to the surface of the substrate body 2 (the surface on the light emission surface side). It does not have to be directly applied to the surface of the substrate body 2. For example, after performing a series of processes such as application of a photosensitive material that does not exhibit sufficient light-shielding property after exposure and development on the surface of the substrate body 2 (surface on the light emission surface side), the light shielding as described above. You may perform the process using the film forming material. Thereby, the light shielding film (black matrix) can be formed thicker.

<B7> Next, as shown in FIG. 7H, the diffusion portion 5 is formed on the surface of the substrate body 2 on which the black matrix 3 is provided (diffusion portion forming step).
The diffusion part 5 is formed by, for example, previously joining a diffusion plate formed into a plate shape or adding a flowable diffusion part forming material that includes a diffusion material and then solidifying the material. can do.
Examples of the method for applying the diffusion portion forming material include various application methods such as doctor blade, spin coating, brush coating, spray coating, electrostatic coating, electrodeposition coating, and roll coater, and the substrate body 2 for forming the diffusion portion. A method such as dipping immersed in the material can be used.

<B8> Next, as shown in FIG. 7 (i), the member 7 with recesses is removed from the substrate body 2 on which the black matrix 3 is formed (member removal step with recesses (transfer process)).
By removing the member 7 with recesses, the lens surface side light-shielding part 4 provided on the member 7 with recesses is transferred to the substrate body 2 side (transfer process). Thereby, the microlens substrate 1 is obtained.

  Further, by removing the member 7 with the recesses, the incident light La can be efficiently refracted in the final microlens substrate 1, and the viewing angle characteristics of the microlens substrate 1 can be made particularly excellent. . Moreover, the removed member 7 with a recessed part can be repeatedly used for manufacture of the board | substrate body 2 (microlens board | substrate 1), and stability of the quality of the manufacturing cost surface and the board | substrate body 2 (microlens board | substrate 1) manufactured are stabilized. It is also advantageous for enhancing the performance.

Further, after the transfer step, heat treatment such as heating and cooling, pressurization of the atmosphere, decompression, and light irradiation may be performed as necessary. Thereby, for example, fixing (stabilization) of the lens surface side light-shielding portion 4 to the substrate body 2 can be promoted. In addition, the shape of the lens surface side light-shielding portion 4 provided on the substrate body 2 can be adjusted.
In the above description, the substrate in which the concave portion is formed by etching is described as being used as the member with the concave portion. However, as described above, the defect of the member with the concave portion is usually likely to occur during the etching. Therefore, after etching, a member provided with a recess (member with a recess) may be repaired. Specific examples of such repair methods include the following methods.

  FIGS. 10A and 10B are diagrams illustrating an example of an apparatus (hereinafter referred to as an inspection / repair apparatus) used for inspecting and repairing the recessed member 7. The inspection / repair device 110 for the member 7 with a recess includes a CCD camera 114, a repairing laser head 111, a mounting table 115 for mounting the member 7 with a recess, a moving stage 112, and a control device 113 incorporating an image processing unit. And have.

  The moving stage 112 moves the CCD camera 114 and the repairing laser head 111 in a plane (X-Y direction, R-θ direction, etc.) with respect to the mounting table. When the inspection signal is input, this is subjected to image processing, and when the flat portion 79 is detected, the repairing laser head 111 is moved to the detection position.

  That is, this inspection / repair device 110 performs the inspection of the member 7 with a recess and the repairing process with the same device. First, the entire range of the member 7 with a recess (a recess was formed by the CCD camera 114). The effective area is scanned. Then, the inspection signal is input to the image processing unit, and image processing is performed to detect the flat portion 79. And when the flat part 79 is detected, the position is memorize | stored (refer Fig.10 (a)).

  When the flat portion 79 is detected in the member 7 with the concave portion and the position is specified, the control device 113 moves the repair laser head 111 directly above the flat portion 79 based on the position signal from the image processing unit. The flat portion 79 is repaired by the repair laser head 111. The flat portion 79 is repaired by forming a recess (repair recess) 71 ″ with a laser (see FIG. 10B).

At this time, although the shape (depth, cross-sectional shape, etc.) of the recess (repair recess) 71 ″ varies depending on the laser irradiation conditions, the microlens substrate 1 obtained using the member 7 with the recess has a scattering effect on the projection light. The flat surface of the flat part 79 disappears or is reduced to such an extent that is obtained. That is, the shape may be such that a pseudo lens is formed.
Although FIG. 10 schematically shows one flat portion 79 and its repair, the number of flat portions 79 is not limited to one in practice. Moreover, as a laser to irradiate, an ultraviolet laser, a femtosecond pulse laser, etc. can be used, for example.

In FIG. 10, the CCD camera 114 and the repairing laser head 111 are installed on a common moving stage 112, but a plurality of moving stages may be provided and each may be installed on a separate moving stage.
The repair may be performed each time the CCD camera detects the flat portion, or when the CCD camera scans the entire surface of the member with the concave portion or the predetermined range, the flat portions detected in the scanning range are collected. May be repaired sequentially.

The inspection method is not limited to the above example, and light is projected from the back surface of the member with a recess, and inspection is performed based on the presence or absence of bright spots (white spots) (same as the presence or absence of scattering of projected light). The uneven shape on the surface of the member with the recess may be directly inspected using a camera or the like.
In this way, in the microlens substrate formed by repairing the concave member having a flat portion, the convex portion (repair lens) is located at a position corresponding to the processing missing portion. Therefore, the projection light is scattered at the convex portion. This more effectively prevents bright spots (white spots) from appearing on the screen having the microlenses, thereby improving the image quality.
Moreover, after performing the above repair, you may perform the mold release process which was mentioned above to the surface side where the repair was performed.

Next, another example (second embodiment) of the method for manufacturing the microlens substrate 1 will be described.
The manufacturing method described below will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
11 and 12 are schematic longitudinal sectional views showing another example (second embodiment) of the method of manufacturing the microlens substrate (lens substrate) shown in FIG. 1, and FIG. 13 is a method of manufacturing the microlens substrate. FIG. 14 is a schematic diagram showing an example of a coating device (droplet discharge device) used in the method of manufacturing a microlens substrate, and FIGS. 15, 16, and 17 are substrate bodies. It is a figure for demonstrating the incident direction of the light at the time of irradiating light (the irradiation method of the light at the time of exposing a photopolymer). In the following description, the lower side in FIGS. 11 and 12 and the upper side in FIGS. 15 to 17 are the “(incident) incident side”, the upper side in FIGS. 11 and 12, and the upper side in FIGS. The lower side is called the “(light) emission side”.

In the above-described embodiment, the light-shielding material is applied to the flat portion 79 of the member 7 with concave portions to form the lens surface side light-shielding portion 4. However, in this embodiment, the flat portion 79 of the member 7 with concave portions is shielded from light. A step of applying a light-shielding material (first light-shielding material applying step), and further a step of applying a light-shielding material 4 ′ to a portion corresponding to the flat portion 28 of the substrate body 2 from which the recessed member 7 is removed. (2nd light-shielding material provision process). Thereby, the suitable lens surface side light-shielding part 4 can be formed in the flat part 28 of the board | substrate body 2 more reliably. For example, according to the method of this embodiment, even if the lens surface side light-shielding part 4 to be formed is relatively thick, it can be suitably formed. Further, when removing the member 7 with the recess from the substrate body 2 (when transferring the lens surface side light shielding portion 4), when the transfer of the lens surface side light shielding portion 4 becomes insufficient (for example, formed lens surface) Even when the side light-shielding part 4 breaks in the layer), according to the method as in this embodiment, the lens surface-side light shielding part 4 can be formed on the flat part 28 of the substrate body 2.
Hereinafter, the manufacturing method of this embodiment will be described in more detail.

<B1 ′> Similar to <B1> in the above-described embodiment (first embodiment) (recessed member preparation step and second light-shielding material application step, see FIGS. 11A and 11B).
<B2 ′> Same as <B2> in the above-described embodiment (first embodiment) (see FIG. 11C).
<B3 ′> Same as <B3> in the above-described embodiment (first embodiment) (see FIG. 11D).

<B4 ′> Next, the flat plate 11 and the member 7 with a recess are removed from the formed substrate body 2 (pressing member / member with a recess removing process (transfer process), see FIG. 11E).
By removing the member 7 with recesses, the lens surface side light-shielding part 4 provided on the member 7 with recesses is transferred to the substrate body 2 side (transfer process).
Further, by removing the member 7 with the recesses, the incident light La can be efficiently refracted in the final microlens substrate 1, and the viewing angle characteristics of the microlens substrate 1 can be made particularly excellent. . Moreover, the removed flat plate 11 and the member 7 with the recess can be repeatedly used for manufacturing the substrate body 2 (microlens substrate 1), and the manufacturing cost and the substrate body 2 to be manufactured (microlens substrate 1) ) Is advantageous in improving the stability of quality.

  <B5 ′> Next, as shown in FIG. 12 (f), the light-shielding material 4 ′ is applied to the portion corresponding to the flat portion 28 of the substrate body 2 (second light-shielding material application step), and the optimum. A lens surface side light-shielding portion 4 is formed (see FIG. 12G). As the light-shielding material 4 ′, the same material as the light-shielding material described in the above-described embodiment can be used, but the light-shielding material 4 ′ used in this step is used in the above-described process <B1 ′>. The light-shielding material may not have the same composition.

  For example, the light shielding material 4 ′ can be selectively applied to a portion corresponding to the flat portion 28 of the substrate body 2 by using the position information obtained in the above-described step <B1 ′>. Further, the flat portion 28 that can transmit straight light may be detected again for the substrate main body 2 from which the flat plate 11 and the concave member 7 are removed in the step <B4 '>. Thereby, in the process up to <B4 ′>, the portion where the light-shielding material is not provided to the portion where the lens-surface-side light-shielding portion 4 having sufficient light-shielding property is formed, and the light-shielding property is insufficient. A light-shielding material can be selectively applied to (the part corresponding to the flat portion 28). For this reason, it is advantageous from the viewpoint of resource saving.

As a method (a method for detecting the flat portion 28) of inspecting the presence of such a flat portion 28 (a flat portion 28 that can transmit straight light; hereinafter, simply referred to as “flat portion 28”), various methods may be used. Although it can use and it does not specifically limit, For example, the method as shown below is applicable.
That is, the presence or absence of the flat portion 28 can be inspected by directly observing the patterning (uneven shape) of the surface of the substrate body 2 with a camera or the like.

  In addition, since the amount of light transmitted through the flat portion 28 (flat portion 28 that can transmit straight light) and the other portions are different, the back surface of the substrate body (the surface on the side where the microlenses 21 are provided). The light is projected, the transmitted light is detected, and the presence or absence of the flat portion 28 is inspected by detecting the difference in the amount of light (for example, the presence or absence of a bright spot (white spot) (same as the presence or absence of scattering of the projection light)). be able to.

In the case of adopting the above method, for example, an inspection apparatus as shown in FIG. 13 can be suitably used.
The inspection apparatus 130 shown in FIG. 13 is a light irradiation unit that irradiates parallel light for inspection from the normal direction (perpendicular direction) of the main surface of the substrate body 2 to the surface side of the substrate body 2 on which the microlenses 21 are provided. 131, a moving stage 132 installed parallel to the main surface of the substrate body 2, and a CCD camera 133 installed movably on the moving stage 132 so as to face the light irradiation means 131. .

  In this inspection apparatus 130, the entire surface of the substrate body 2 (an effective area where the microlenses 21 are formed) is scanned by the CCD camera 133. Then, the inspection signal obtained by scanning is input to the image processing device 134, and image processing is performed to detect the flat portion 28 (the flat portion 28 that can transmit straight light). If detected, the position information is stored in a storage means (not shown).

And if the flat part 28 (flat part 28 which can permeate | transmit straight light) is detected in the board | substrate body 2, light-shielding material 4 'will be provided to this location. The application of the light shielding material 4 ′ can be performed based on position information obtained by scanning with the CCD camera 121.
The method for applying the light-shielding material 4 ′ is not particularly limited, but it is preferable to apply an inkjet method. According to the inkjet method, the light shielding material 4 ′ can be selectively and reliably applied to the flat portion 28 that can transmit straight light. Moreover, according to the inkjet method, the application of the light-shielding material 4 ′ can be accelerated, and the light-shielding material 4 ′ can be used effectively, which is preferable from the viewpoint of resource saving.

The application of the light-shielding material 4 ′ by ink jetting can be suitably performed using a droplet discharge device (coating device) as shown in FIG.
A droplet discharge device (coating device) 140 shown in FIG. 14 has a movable stage 142 installed in parallel to the main surface of the substrate body 2 and a droplet discharge movably mounted or suspended on the movable stage 142. A head (inkjet head) 141 and a control device 143 that receives position information specified in the inspection and controls the driving of the droplet discharge head 141 and the like are provided.

  In the droplet discharge device 140, the droplet discharge head 141 is moved to a predetermined portion by the control signal of the control device 143 to which the position information in the inspection is input, and the light amount data corresponding to the portion is stored. Based on this, a light-shielding material 4 ′ as a droplet is ejected in a predetermined amount under a predetermined condition. Thereby, the optimal lens surface side light-shielding part 4 can be formed for each flat part 28.

<B6 ′> Same as <B5> in the above-described embodiment (first embodiment) (see FIG. 12H).
<B7 ′> Next, the black matrix 3 having the openings 31 is formed in the same manner as in <B6> in the above-described embodiment (first embodiment) (see FIG. 12I).
However, in the present embodiment, irradiation with light (exposure light) Lb is performed without using the member 7 with concave portions. For this reason, when the light (exposure light) Lb is irradiated from the normal direction (perpendicular direction) of the main surface of the substrate body 2, the light is irradiated through the recessed member 7 as in the first embodiment. Compared with the case where it does, the opening part 31 formed becomes a small thing.

  Therefore, in this embodiment, as shown in FIG. 15, light is incident on the substrate body from a direction inclined by a predetermined angle θ with respect to the normal direction (perpendicular direction) of the main surface of the substrate body. In this way, when light is incident, an opening is formed when light is irradiated in a direction perpendicular to the incident-side surface of the substrate body 2 (normal direction of the main surface of the substrate body 2). Even the part that cannot be irradiated can be irradiated with light having sufficiently high luminous intensity (energy), and the part can be the opening 31 of the black matrix (light-shielding film) 3. As a result, the black matrix 3 having the relatively large (necessary and sufficient size) opening 31 can be formed easily and reliably.

  When irradiating light (exposure light) Lb, light (exposure light) Lb is incident on the substrate body 2 from a direction inclined by a predetermined angle θ with respect to the normal direction of the main surface of the substrate body 2. For example, the light source of the exposure light Lb may be installed obliquely, or the substrate body 2 side may be inclined. Moreover, when irradiating between a light source and the board | substrate body 2 via a polarizing filter, a slit, etc., you may incline the said polarizing filter, a slit, etc. diagonally.

  The method of inclining the substrate body 2 is not particularly limited, and for example, the substrate body 2 may be inclined by lifting and supporting one end portion of the substrate body 2 using a support member or the like. The substrate body 2 may be inclined obliquely by arranging an inclined member having an inclined shape such as the lower side of the substrate body 2. In this case, the material of the inclined member is preferably one that does not reflect the exposure light Lb.

  The angle θ formed between the incident direction of light and the normal direction of the main surface of the substrate body 2 is not particularly limited, but is preferably 2 to 15 °, more preferably 3 to 10 °, More preferably, it is 8 °. When the angle θ is a value within the above range, the black matrix 3 (the black matrix 3 having the opening 31 having a predetermined size and the black matrix 3 having the predetermined opening ratio) as described above is more reliably formed. Both the contrast and viewing angle characteristics of the displayed image can be made particularly excellent. On the other hand, if the angle θ is less than the lower limit, it becomes difficult to form a sufficiently large opening 31 or to make the aperture ratio of the black matrix 3 sufficiently high. It may be difficult to make the viewing angle characteristics sufficiently excellent. On the other hand, when the angle θ exceeds the upper limit, the external light antireflection characteristic of the black matrix 3 to be formed is deteriorated, and it may be difficult to sufficiently improve the contrast of the obtained image. There is sex. If the angle θ exceeds the upper limit, depending on the shape of the microlens 21 and the like, it may be difficult to reliably form the opening 31 in a portion corresponding to the top of the microlens 21.

The light (exposure light) Lb applied to the substrate body 2 is not particularly limited, but is preferably parallel light. As a result, the size of the opening 31 to be formed, the aperture ratio of the black matrix 3 and the like can be controlled more reliably, and the contrast and viewing angle characteristics of the displayed image can be more reliably improved. It can be excellent.
Moreover, it is preferable that the light for forming an opening (exposure light) Lb is incident not only from one direction but also from a plurality of directions on the substrate body 2. Accordingly, light having a sufficient luminous intensity (light flux) can be efficiently applied to a wider area, and the opening 31 having a necessary and sufficient size can be formed more efficiently.

  As a method of making light incident from a plurality of directions, for example, a plurality of light sources are prepared, these are installed in different parts, and light is emitted from the plurality of light sources simultaneously or sequentially, or is emitted from the light sources. There is also a method in which light is branched and the branched light is incident on the substrate body 2 from different directions. For example, there is a method of irradiating Lb. As a method of relatively moving (displacement) the substrate body 2 and the light source, for example, a method of moving (displacement) the light source while the substrate body 2 is fixed, or moving the substrate body 2 while the light source is fixed ( For example, a method for moving (displace) the light source and the substrate body 2 together.

Hereinafter, a method for moving (displacement) the substrate body 2 will be described more specifically.
As a specific method of moving the substrate body 2 side, for example, as schematically shown in FIG. 16, there is a method of inclining the substrate body 2 by at least an angle θ in at least four directions orthogonal to each other.
In this way, by moving the substrate body 2, for example, the obtained microlens substrate 1 can have particularly excellent viewing angle characteristics in each direction (left and right direction and up and down direction).

  The light (exposure light) Lb may be irradiated only when the substrate body 2 is inclined at a predetermined angle. However, the substrate body 2 is moved continuously or intermittently while the substrate body 2 is moved. You may do it. That is, the value of the angle θ may change over time. Thereby, for example, even when the value of the angle θ (the maximum value of the angle θ) is relatively large, the opening 31 can be reliably formed at a site corresponding to the top of the microlens 21. Thus, when the value of the angle θ changes with time, it is preferable that the maximum value is included in the above-described range. Further, for example, there may be a point in time when the angle θ becomes zero when the light (exposure light) Lb is irradiated.

  Further, when the light (exposure light) Lb is irradiated from a plurality of directions, the maximum value of the incident angle θ of the light (exposure light) Lb in each direction may be different. Thereby, for example, the opening 31 having a complicated shape such as the opening 31 having an asymmetric shape (for example, not point-symmetric) can be easily and reliably formed. Thereby, for example, the viewing angle characteristics in each direction can be easily optimized in accordance with the specifications of the transmissive screen 10 and the rear projector 300 as will be described later and the usage environment (installation location, etc.). .

FIG. 17 schematically shows another example of the method of changing the light incident direction (another example of moving the substrate body 2 side).
In the example shown in FIG. 17, the substrate body 2 is placed on the shaft 90 so that the angle formed between the normal line of the main surface of the substrate body 2 and the longitudinal direction of the shaft 90 maintains a predetermined angle θ. It is configured to rotate. In other words, in the example shown in FIG. 17, the normal line of the main surface of the substrate body 2 at the portion where the extension line of the shaft 90 contacts the surface (incident surface) of the substrate body 2 is the circumference of the cone centering on the shaft 90. The substrate body 2 rotates to form a surface. With this configuration, for example, the light Lb is incident while the normal of the main surface of the substrate body 2 is inclined by the angle θ with respect to the incident direction of the light (exposure light) Lb. The direction can be changed over time. As a result, the microlens substrate 1 having particularly excellent both contrast and viewing angle characteristics of the displayed image can be manufactured with high productivity.

<B8 ′> Thereafter, similarly to <B7> in the above-described embodiment (first embodiment), the diffusion portion 5 is formed on the surface side of the substrate body 2 on which the black matrix 3 is provided (the diffusion portion). Forming step). Thereby, the microlens substrate 1 is obtained.
A rear projector using the transmission screen will be described below.
FIG. 18 is a diagram schematically showing the configuration of the rear projector of the present invention.
As shown in the figure, the rear projector 300 has a configuration in which a projection optical unit 310, a light guide mirror 320, and a transmissive screen 10 are arranged in a housing 340.

Since the rear projector 300 includes the transmission screen 10 as described above, it is possible to display an excellent image with excellent contrast and suppressed generation of bright spots. In addition, the viewing angle characteristics, light utilization efficiency, etc. are particularly excellent.
In particular, in the microlens substrate 1 described above, since the elliptical microlenses 21 are arranged in a staggered pattern (in a staggered pattern), the rear projector 300 is not particularly susceptible to problems such as moire.

As mentioned above, although this invention was demonstrated based on embodiment of illustration, this invention is not limited to these.
For example, each part of the lens substrate (microlens substrate), the transmission screen, and the rear projector can be replaced with any component that can exhibit the same function. Moreover, you may add arbitrary structures. For example, the lens substrate may have a colored portion colored at a predetermined density near the surface thereof. Thereby, the contrast of the displayed image can be further improved.

Moreover, in the manufacturing method of a lens substrate (microlens substrate), you may add arbitrary processes.
Moreover, the order of each process in the manufacturing method of a lens substrate is not limited to what was mentioned above, You may change the order as needed.
Moreover, in embodiment mentioned above, although demonstrated as what gives a composition to the surface of a member with a recessed part, for example, a composition is provided to the surface of a flat plate (or the base film mounted on the flat plate), You may manufacture a microlens board | substrate by pressing this with a member with a recessed part.

Moreover, in embodiment mentioned above, although demonstrated as what manufactures a board | substrate body using a plate-shaped member with a recessed part, you may manufacture a board | substrate body using a roll-shaped member with a recessed part, for example.
In the first embodiment, when forming the black matrix (light-shielding film), light (exposure light) is emitted from the normal direction of the main surface to the substrate body to which the light-shielding film-forming material is applied. However, as in the second embodiment, light (exposure light) may be irradiated from a direction inclined by a predetermined angle θ with respect to the normal spring on the main surface of the substrate body. .

Moreover, when forming the black matrix (light-shielding film), the light (exposure light) may be irradiated from the normal direction of the main surface of the substrate body, for example, by removing the recessed member. Good.
Further, in the above-described embodiment, the member with the concave portion is described as being removed, but the member with the concave portion may not necessarily be removed. That is, the concave member may constitute a part of the lens substrate.

  In the above-described embodiment, the microlens substrate has been described as having a layered diffusion portion, but the shape of the diffusion portion is not limited to this. For example, the diffusion portion may be provided in a convex shape at a portion corresponding to the opening of the black matrix. Even in such a case, the effects described above can be obtained. In addition, by forming such a diffusion portion, it is possible to more effectively prevent reflection of external light at a portion other than the opening portion of the black matrix, so that the contrast of the obtained image is particularly excellent. can do. Further, the microlens substrate may not include the diffusion portion as described above. In such a case, the light utilization efficiency can be made particularly excellent.

In the above-described embodiment, the lens substrate is described as a microlens substrate including a microlens. However, in the present invention, the lens substrate may be, for example, a lenticular lens substrate.
In the above-described embodiment, the transmission screen is described as including a microlens substrate and a Fresnel lens portion. However, the transmission screen of the present invention does not necessarily include a Fresnel lens portion. Good. For example, the transmission screen of the present invention may be substantially constituted only by the microlens substrate of the present invention.

  In the above-described embodiment, the lens substrate is described as a member constituting a transmission screen and a rear projector. However, the use of the lens substrate of the present invention is not limited to the above, It can be anything. For example, the lens substrate of the present invention is applied to a diffusion plate, a black matrix screen, a projection display device (front projector) screen (front projection screen), a liquid crystal light valve component of a projection display device (front projector), and the like. It may be done.

Example 1
The member with a recessed part provided with the recessed part for microlens formation was manufactured as follows.
First, a soda glass substrate (absolute refractive index n ₂ : 1.50) having a width of 1.2 m × length of 0.7 m square and a thickness of 4.8 mm was prepared as a substrate.
This soda glass substrate was immersed in a cleaning solution containing 4 wt% ammonium monohydrogen difluoride and 8 wt% hydrogen peroxide and etched by 6 μm to clean the surface.
Thereafter, cleaning with pure water and drying using N ₂ gas (removal of pure water) were performed.

  Next, a chromium / chromium oxide laminate (a laminate in which chromium oxide was laminated on the outer surface side of chromium) was formed on the soda glass substrate by sputtering. That is, a mask forming film and a back surface protective film made of a chromium / chromium oxide laminate were formed on the surface of a soda glass substrate. The thickness of the chromium layer was 0.03 μm, and the thickness of the chromium oxide layer was 0.01 μm.

Next, laser processing was performed on the mask forming film to form a large number of initial holes in a range of 113 cm × 65 cm in the central portion of the mask forming film, thereby forming a mask.
The laser processing was performed using an excimer laser under the conditions of an energy density of 1.2 J / cm ² , a beam diameter of 2 μm at the processing point, and a scanning speed of 0.1 m / sec.
As a result, substantially circular initial holes were formed in a staggered pattern over the entire range of the mask forming film. The diameter of the initial hole was 2 μm.

Next, wet etching was performed on the soda glass substrate to form concave portions (recesses for forming microlenses) having a flat shape (substantially elliptical shape) when viewed in plan on the soda glass substrate. The formed recess has a spherical surface, and the length (pitch) in the minor axis direction is 54 μm, the length in the major axis direction is 72 μm, the radius of curvature is 38 μm, and the depth is 38 μm. Moreover, the occupation rate of the recessed part in the effective area | region in which the recessed part was formed was 98%.
In the wet etching, an aqueous solution containing 4 wt% ammonium monohydrogen difluoride and 8 wt% hydrogen peroxide was used as an etchant, and the immersion time was 2.0 hours.

Next, the mask and the back surface protective film were removed by etching using a mixture of ceric ammonium nitrate and perchloric acid.
Next, cleaning with pure water and drying (removing pure water) using N ₂ gas were performed.
Thereafter, a gas phase surface treatment (silylation treatment) with hexamethyldisilazane was performed on the surface side of the substrate where the concave portions were formed, thereby forming a release treatment portion.
Thereby, the member with a recessed part in which many recessed parts for microlens formation were arranged on the soda glass substrate in zigzag form was obtained.

Next, the inspection apparatus shown in FIG. 8 was used to inspect the member with concave portions, a flat portion having a predetermined size (width 5 μm) or more was detected, and the position information was stored in the storage means. The surface roughness Ra of the flat portion was 5 μm or less.
And based on the memorize | stored positional information, the light-shielding material was provided to the said flat part by roller application | coating. The thickness of the light shielding material applied to the flat portion was 1.5 μm.
Thereby, the lens surface side light-shielding part was selectively formed on the flat part of the member with a recessed part.

Next, a composition composed of unpolymerized (uncured) acrylic resin (PMMA resin (methacrylic resin)) is applied to the surface of the member with recesses on the side where the recesses are formed. A substrate film (thickness: 50 μm) made of terephthalate (PET) was placed. The refractive index (absolute refractive index n ₁ ) of polyethylene terephthalate constituting the base film was 1.57.

Next, the said composition was pressed through the base film with the flat plate comprised with soda glass. At this time, air was prevented from entering between the base film and the composition.
Then, the composition was completely hardened by irradiating the composition with ultraviolet rays while being pressed with a flat plate to obtain a substrate body. The obtained substrate main body had a microlens having a shape corresponding to the concave portion of the concave member. The formed microlens has a flat shape (substantially elliptical shape), the length (pitch) in the minor axis direction is 54 μm, the length in the major axis direction is 72 μm, the radius of curvature is 38 μm, and the depth is It was 38 μm. Further, the occupation ratio of the microlens in the effective region where the microlens is formed was 98%. Further, the refractive index (absolute refractive index n ₁ ) of the material constituting the formed cured portion was 1.56.

Next, the flat plate was removed from the substrate body.
Next, a positive type photopolymer (PC405G: JSR Corporation) in which carbon black (light-shielding material) is added to the surface of the substrate main body on the emission side (surface opposite to the surface on which the microlenses are formed). Made by a roll coater. The content of carbon black in the photopolymer (light shielding film forming material) was 20 wt%.

Next, a pre-bake treatment at 90 ° C. for 30 minutes was performed.
Next, ultraviolet rays as parallel light of 10 mJ / cm ² were irradiated from the surface side of the substrate main body on which the microlenses were formed through the member with concave portions. As a result, the irradiated ultraviolet rays were collected by each microlens, and the photopolymer of the portion irradiated with the collected ultraviolet rays was selectively exposed.

Thereafter, development was performed for 40 seconds using a 0.5 wt% aqueous KOH solution.
Thereafter, pure water cleaning and drying using N ₂ gas (removal of pure water) were performed, and a post-baking treatment at 200 ° C. for 30 minutes was further performed. Thereby, a black matrix having openings corresponding to the respective microlenses was formed. The opening was substantially circular, and its diameter was 30 μm. The formed black matrix had a thickness of 1.2 μm. Moreover, the aperture ratio of the black matrix was 18%.

Next, a diffusion portion was formed on the side of the substrate body on which the black matrix was formed. The diffusion portion was formed by joining a diffusion plate having a configuration in which a diffusion material (silica particles having an average particle size of 8 μm) was dispersed in an acrylic resin by heat fusion. Note that the thickness of the diffusion portion was 2.0 mm.
Then, the member with a recessed part was removed. As a result, a microlens substrate in which the lens surface side light-shielding portion was transferred from the member with concave portions to the flat portion (surface roughness Ra of 5 μm or less) of the substrate body was obtained. The thickness of the light shielding part on the lens surface side of the microlens substrate was 1.5 μm.
A transmissive screen as shown in FIG. 3 was obtained by assembling the microlens substrate manufactured as described above and the Fresnel lens portion manufactured by extrusion molding.

(Example 2)
For those manufactured in the same manner as the member with recesses used in Example 1, using the inspection / repair device shown in FIG. 10, a repair recess is formed in the flat portion where no recess is formed, and then, A microlens substrate and a transmissive screen were produced in the same manner as in Example 1 except that a material subjected to gas phase surface treatment (silylation treatment) with hexamethyldisilazane was used as a member with a recess. In the member with recesses used in this example, the occupation ratio of the recesses in the effective region where the recesses were formed was 98%.

(Example 3)
First, in the same manner as in Example 1, a member with a recess was manufactured.
Next, the inspection apparatus shown in FIG. 8 was used to inspect the member with concave portions, a flat portion having a predetermined size (width 5 μm) or more was detected, and the position information was stored in the storage means. The surface roughness Ra of the flat portion was 5 μm or less.

And based on the memorize | stored positional information, the light-shielding material was provided to the said flat part by roller application | coating. The thickness of the light shielding material applied to the flat portion was 1.5 μm.
Thereby, the lens surface side light-shielding part was selectively formed on the flat part of the member with a recessed part.
Next, a composition composed of an unpolymerized (uncured) acrylic resin (PMMA resin (methacrylic resin)) is applied to the surface on which the concave portion of the member with concave portions is formed, and polyethylene is formed thereon. A substrate film (thickness: 50 mm) made of terephthalate (PET) was placed. The refractive index (absolute refractive index n ₁ ) of polyethylene terephthalate constituting the base film was 1.57.

Next, the said composition was pressed through the base film with the flat plate comprised with soda glass. At this time, air was prevented from entering between the base film and the composition.
Then, the composition was completely hardened by irradiating the composition with ultraviolet rays while being pressed with a flat plate to obtain a substrate body. The obtained substrate main body had a microlens having a shape corresponding to the concave portion of the concave member. The formed microlens had a flat shape (substantially elliptical shape), and had a length in the major axis direction of 72 μm, a radius of curvature of 38 μm, and a height of 38 μm. Further, the occupation ratio of the microlens in the effective region where the microlens is formed was 98%. Further, the refractive index (absolute refractive index n ₁ ) of the material constituting the formed cured portion was 1.56.

Next, the flat plate and the concave member were removed from the substrate body. Thereby, the lens surface side light-shielding part was transferred from the member with concave portions to the flat part (surface roughness Ra of 5 μm or less) of the substrate body.
Next, using the inspection apparatus shown in FIG. 13, the substrate main body was inspected, a flat portion having a predetermined size (width 5 μm) or more was detected, and the position information was stored in the storage means. The surface roughness Ra of the flat portion was 5 μm or less.
And based on the memorize | stored positional information, the light-shielding material was provided to the said flat part with the inkjet method using the droplet discharge apparatus shown in FIG.
Thereafter, the solvent was removed from the applied light shielding material to form a lens surface side light shielding portion having a thickness of 1.7 μm.

Next, a positive type photopolymer (PC405G: JSR Corporation) in which carbon black (light-shielding material) is added to the surface of the substrate main body on the emission side (surface opposite to the surface on which the microlenses are formed). Made by a roll coater. The content of carbon black in the photopolymer (light shielding film forming material) was 20 wt%.
Next, a pre-bake treatment at 90 ° C. for 30 minutes was performed.

Next, as shown in FIG. 17, the surface side of the substrate body on which the microlenses are provided is the upper side, and irradiation with ultraviolet light as parallel light of 60 mJ / cm ² is performed from the upper side of the substrate body in the longitudinal direction of the shaft. The substrate main body was rotated on the shaft in such a manner that the angle formed between the normal line of the main surface of the substrate main body and the longitudinal direction of the shaft maintained a predetermined angle (θ = 7 °). In other words, in this embodiment, the main body of the substrate main body at the portion where the extension line of the shaft contacts the surface (incident surface) of the substrate main body while irradiating ultraviolet rays as parallel light of 10 mJ / cm ^{2 in} the longitudinal direction of the shaft. The substrate body was rotated so that the surface normal formed a conical circumferential surface about the axis.

As a result, the irradiated ultraviolet rays were collected by each microlens, and the photopolymer of the portion irradiated with the collected ultraviolet rays was selectively exposed.
Thereafter, development was performed for 40 seconds using a 0.5 wt% aqueous KOH solution.
Thereafter, pure water cleaning and drying using N ₂ gas (removal of pure water) were performed, and a post-baking treatment at 200 ° C. for 30 minutes was further performed. Thereby, a black matrix having openings corresponding to the respective microlenses was formed. The opening was substantially circular, and its diameter was 30 μm. The formed black matrix had a thickness of 1.2 μm.
Thereafter, in the same manner as in Example 1, a microlens substrate was obtained by forming a diffusion portion.
Thereafter, a transmissive screen was produced in the same manner as in Example 1 using the obtained microlens substrate.

Example 4
For those manufactured in the same manner as the member with recesses used in Example 1, using the inspection / repair device shown in FIG. 10, a repair recess is formed in the flat portion where no recess is formed, and then, A microlens substrate and a transmissive screen were produced in the same manner as in Example 3 except that a material subjected to gas phase surface treatment (silylation treatment) with hexamethyldisilazane was used as a member with a recess. In the member with recesses used in this example, the occupation ratio of the recesses in the effective region where the recesses were formed was 98%.

(Example 5)
Next, in the step of removing the flat plate from the substrate body, the member with concave portions is also removed together with the flat plate, and the subsequent exposure step is performed in the same manner as in Example 1 except that the substrate with concave portions is removed. A substrate and a transmission screen were produced.
(Example 6)
The same as in Example 5 except that a light-shielding material was applied by roller application to the surface side where the concave portion of the member with concave portion was formed without performing an inspection for detecting the flat portion of the member with concave portion. A microlens substrate and a transmission screen were manufactured.

(Comparative Example 1)
A microlens substrate and a transmissive screen were manufactured in the same manner as in Example 1 except that when the substrate body was produced using the member with recesses, the light shielding material was not applied to the flat part of the member with recesses. did. That is, in this comparative example, the microlens substrate does not include the lens surface side light-shielding portion.

(Comparative Example 2)
A microlens substrate and a transmissive screen were produced in the same manner as in Comparative Example 1 except that the black matrix was not formed after the substrate body was produced. That is, in this comparative example, the microlens substrate does not include the black matrix and the lens surface side light-shielding portion.
For each example and each comparative example, Table 1 summarizes the configuration of the member with recesses used for manufacturing and the configuration of the microlens substrate.

[Production of rear projector]
Rear projectors as shown in FIG. 18 were produced using the transmissive screens of the respective examples and comparative examples.
[Generation of bright spots]
Sample images were displayed on the transmissive screens of the rear projectors of each of the examples and comparative examples, and in the displayed images, the state of occurrence of bright spots was evaluated according to the following five criteria.

A: A bright spot does not exist or cannot be confirmed visually.
B: There are a small number of bright spots on a part of the screen, which can be confirmed slightly.
C: A bright spot exists in a part of the screen and can be clearly confirmed visually.
D: There are a small number of bright spots on the entire screen, which can be clearly confirmed visually.
E: Many bright spots exist on the entire screen, which can be clearly confirmed visually.

[Evaluation of brightness (luminance)]
Sample images were displayed on the transmissive screens of the rear projectors of the respective examples and comparative examples, and the brightness (luminance) of the displayed images was evaluated according to the following six criteria. Evaluation of brightness (luminance) was performed in a bright room and a dark room. The evaluation in the bright room was performed in an environment where the ambient light illuminance was about 185 lx. Evaluation in the dark room was performed in an environment where the illuminance of outside light was 0.1 lx or less.

A: A very bright image could be displayed.
B: A sufficiently bright image could be displayed.
C: A relatively bright image could be displayed.
D: The displayed image was a little dark.
E: The displayed image was dark.
F: The displayed image was very dark.

[Evaluation of contrast]
Contrast evaluation was performed on the rear projectors of each of the examples and comparative examples.
As contrast (CNT), the front luminance (white luminance) LW [cd / m ² ] of white display when all white light of 373 lx is incident in the bright room and the front of black display when the light source is completely turned off in the bright room The ratio LW / LB with the luminance LB [cd / m ² ] was determined. The black luminance increase amount is an increase amount with respect to the black display luminance in the dark room. The measurement in the bright room was performed under an environment where the ambient light illuminance was about 82 lx. The measurement in the dark room was performed in an environment where the external light illuminance was 0.1 lx or less.

[Measurement of viewing angle]
With the sample images displayed on the transmissive screens of the rear projectors of the examples and comparative examples, the viewing angles in the vertical direction (up and down direction) and the horizontal direction (left and right direction) were measured.
The viewing angle was measured under the condition of measuring with a variable angle photometer (goniophotometer) at intervals of 1 degree.
These results are summarized in Table 2.

  As can be seen from Table 2, in the present invention, bright spots were sufficiently prevented and a high contrast image could be displayed. Also, the viewing angle characteristics were excellent. On the other hand, in each comparative example, a satisfactory result was not obtained.

It is a typical longitudinal section showing a suitable embodiment of a micro lens substrate (lens substrate) of the present invention. FIG. 2 is a plan view of the microlens substrate shown in FIG. 1. It is a typical longitudinal cross-sectional view which shows suitable embodiment of the transmission type screen of this invention provided with the micro lens board | substrate (lens board | substrate) shown in FIG. It is a typical longitudinal section showing a member with a crevice used for manufacture of a micro lens substrate. It is a typical longitudinal cross-sectional view which shows the manufacturing method of the member with a recessed part shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st Embodiment) of the manufacturing method of the micro lens board | substrate (lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st Embodiment) of the manufacturing method of the micro lens board | substrate (lens board | substrate) shown in FIG. It is a schematic diagram which shows an example of the inspection apparatus used in the manufacturing method of a micro lens board | substrate. It is a figure for demonstrating refraction of the light by a micro lens, and the luminous intensity distribution of the light radiate | emitted from a board | substrate body. It is a schematic diagram which shows an example of the inspection repair apparatus used in the manufacturing method of a member with a recessed part. It is a typical longitudinal cross-sectional view which shows another example (2nd Embodiment) of the manufacturing method of the micro lens board | substrate (lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd Embodiment) of the manufacturing method of the micro lens board | substrate (lens board | substrate) shown in FIG. It is a schematic diagram which shows an example of the inspection apparatus used in the manufacturing method of a micro lens board | substrate. It is a schematic diagram which shows an example of the coating device (droplet discharge device) used in the manufacturing method of a micro lens substrate. It is a figure for demonstrating the incident direction (light irradiation method at the time of exposing a photopolymer) at the time of irradiating light to a substrate main body. It is a figure for demonstrating the incident direction (light irradiation method at the time of exposing a photopolymer) at the time of irradiating light to a substrate main body. It is a figure for demonstrating the incident direction (light irradiation method at the time of exposing a photopolymer) at the time of irradiating light to a substrate main body. It is a figure which shows typically the rear type projector to which the transmission type screen of this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Microlens board | substrate (lens board | substrate) 2 ... Board | substrate main body 21 ... Microlens (convex lens) 23 ... Composition 24 ... Base film 25 ... 1st row | line 26 ... 2nd row 28 ... Flat part 3 ... Black matrix ( (Light shielding film) 31 ... opening 32 ... photopolymer (light shielding film forming material) 4 ... lens surface side light shielding part 4 '... light shielding material 5 ... diffusion part 6 ... Fresnel lens part 61 ... Fresnel lens 7 ... member with concave part ( Microlens forming concave member 71... Concave portion (microlens forming concave portion) 71 ′. Concave portion 71 ″ concave portion (repair concave portion) 79. Flat portion 70 ... substrate 8 ... mask 81 ... initial hole (opening portion) 89 ... Back surface protective film 80 ... Mask forming film 90 ... Shaft 11 ... Flat plate 10 ... Transmission type screen 110 ... Inspection and repair device 111 ... Repair laser head 112 ... Moving stage 11 ... Control device 114 ... CCD camera 115 ... Place 120 ... Inspection device 121 ... CCD camera 122 ... Moving stage 123 ... Image processing device 130 ... Inspection device 131 ... Light irradiation means 132 ... Moving stage 133 ... CCD camera 134 ... Image processing device DESCRIPTION OF SYMBOLS 140 ... Droplet discharge apparatus (coating apparatus) 141 ... Droplet discharge head 142 ... Moving stage 143 ... Control apparatus 300 ... Rear type projector 310 ... Projection optical unit 320 ... Light guide mirror 340 ... Case

Claims (15)

A method of manufacturing a lens substrate having a substrate body having a large number of convex lenses and a light-shielding film made of a light-shielding material and having an opening,
Preparing a member with a recess having a recess corresponding to the convex lens;
A light-shielding material is applied to the top of a convex portion having a height higher than a predetermined value among the convex portions existing between adjacent concave portions on the surface of the member with the concave portion where the concave portion is provided. A light-shielding material application step,
A composition applying step for applying a composition having fluidity to the surface of the recessed portion of the member provided with the recess;
Solidifying the composition to obtain a substrate body;
A light-shielding film-forming material application step for applying a light-shielding film-forming material for forming the light-shielding film on the surface of the substrate body opposite to the surface on which the convex lens is provided;
A method of manufacturing a lens substrate, comprising: an opening forming step of applying light to the light shielding film forming material through the substrate body to form the light shielding portion having the opening.   The method for manufacturing a lens substrate according to claim 1, wherein a top portion of the convex portion to which the light shielding material is applied is a flat portion that does not function as a lens portion. A method of manufacturing a lens substrate having a substrate body having a large number of convex lenses and a light-shielding film made of a light-shielding material and having an opening,
Preparing a member with a recess having a recess corresponding to the convex lens;
On the surface on the side where the concave portion of the member with concave portions is provided, it is inspected whether a flat portion having a predetermined size or more exists between adjacent concave portions, and the flat portion exists. In the case, a light-shielding material application step of applying a light-shielding material to the flat portion,
A composition applying step for applying a composition having fluidity to the surface of the recessed portion of the member provided with the recess;
Solidifying the composition to obtain a substrate body;
A light-shielding film-forming material application step for applying a light-shielding film-forming material for forming the light-shielding film on the surface of the substrate body opposite to the surface on which the convex lens is provided;
A method of manufacturing a lens substrate, comprising: an opening forming step of applying light to the light shielding film forming material through the substrate body to form the light shielding portion having the opening.   The method for manufacturing a lens substrate according to claim 1, wherein, in the light shielding material application step, the light shielding material is applied by roller coating.   5. The method for manufacturing a lens substrate according to claim 1, wherein in the light shielding material application step, the light shielding material is applied in a thickness of 0.8 to 1.2 μm.   The method for manufacturing a lens substrate according to claim 1, further comprising a member-with-recess removing step for removing the member with a recessed portion from the substrate body after the solidification step.   The manufacturing method of the lens substrate according to claim 6 which has the member removal process with a crevice after the opening part formation process.   The convex lens to be formed has a spherical surface, and the distance between the tops of the adjacent convex lenses on the lens substrate is smaller than a value obtained by multiplying the radius of curvature of the convex lens to be formed by 2. A method for producing a lens substrate according to any one of 1 to 7.   The method for manufacturing a lens substrate according to claim 1, wherein the lens substrate is a microlens substrate including a microlens as the convex lens.   The method for manufacturing a lens substrate according to any one of claims 1 to 9, wherein a mold release process is performed on a surface of the member having the recesses on the side where the recesses are provided.   A lens substrate manufactured using the method according to claim 1. A lens substrate having a substrate body having a large number of convex lenses and a light-shielding film made of a light-shielding material and having an opening,
On the surface of the substrate body on the side where the convex lens is provided, a flat portion having a predetermined size or more is provided between the adjacent convex lens and the convex lens.
A lens substrate, wherein a lens surface side light shielding part made of a light shielding material is selectively provided on the flat part.   A transmissive screen comprising the lens substrate according to claim 11. A Fresnel lens part having a Fresnel lens formed on the light exit side;
A transmissive screen comprising: the lens substrate according to claim 11 or 12 disposed on a light emission side of the Fresnel lens portion. A rear projector comprising the transmissive screen according to claim 13.

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