JP2007148174A - Lens substrate, lens substrate manufacturing method, transmissive screen, and rear projector - Google Patents

Abstract

An object of the present invention is to provide a lens substrate capable of displaying an image having excellent light utilization efficiency, excellent viewing angle characteristics, and excellent contrast, and a manufacturing method capable of efficiently manufacturing the lens substrate. And a transmissive screen and a rear projector including the lens substrate.
A microlens substrate 1 of the present invention comprises a substrate body (plate member) 2 having a plate shape and having a large number of lens portions provided on one surface side. On the side opposite to the side on which the (lens part) 21 is provided, there is a light shielding part 22 having a function of preventing reflection of external light, and the light shielding part 22 corresponds to the light collecting part of the microlens 21. It is characterized in that it is provided inside the substrate body 2 by dyeing at a site other than the site. The thickness of the light shielding part 22 is preferably 0.1 to 50 μm.
[Selection] Figure 1

Description

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

In recent years, the demand for rear projectors (rear projection projection televisions) is increasing as a display suitable for home theater monitors, large screen televisions, and the like.
In such a rear projector, in order to increase the contrast of an image, it is required to suppress external light reflection while suppressing a decrease in intensity of image light.
In order to achieve such an object, a light-shielding layer made of a light-shielding resin composition containing a light-shielding colorant and a resin is laminated on the other surface of a transparent sheet having a lenticular lens on one surface. A lenticular lens sheet (lens substrate) has been proposed (see, for example, Patent Document 1).

  In such a lens substrate, the light-shielding layer has an opening in the vicinity of the condensing part of the lenticular lens, but the light-shielding layer has a predetermined thickness, so that the transparent sheet is transmitted. A part of the light (light refracted by the lenticular lens comparatively greatly) is incident on the side surface (thickness direction surface) of the light-shielding layer and absorbed by the light-shielding layer. There is a problem that the viewing angle characteristics are remarkably deteriorated (see FIG. 21).

JP 2002-350981 A

  An object of the present invention is to provide a lens substrate capable of displaying an image with excellent light utilization efficiency, excellent viewing angle characteristics, and excellent contrast, and to efficiently manufacture the lens substrate. Another object of the present invention is to provide a manufacturing method that can be used, and to provide a transmissive screen and a rear projector including the lens substrate.

Such an object is achieved by the present invention described below.
The lens substrate of the present invention is a lens substrate formed of a plate-like member having a plate shape and a large number of lens portions provided on one surface side,
A light-shielding portion having a function of preventing reflection of external light on the side opposite to the side where the lens portion is provided;
The light-shielding part is provided inside the plate-like member by dyeing at least in a part other than the part corresponding to the light condensing part of the lens part.
Accordingly, it is possible to provide a manufacturing method that can efficiently manufacture a lens substrate that is excellent in light utilization efficiency, excellent in viewing angle characteristics, and capable of displaying an image with excellent contrast.

In the lens substrate of the present invention, it is preferable that the thickness of the light shielding portion is 0.1 to 50 μm.
Thereby, it is possible to display an image with more excellent contrast while sufficiently improving the light use efficiency and viewing angle characteristics.
The lens substrate of the present invention preferably includes a diffusing portion having a function of diffusing light on the surface side of the plate-like member provided with the light shielding portion.
Thereby, the viewing angle characteristic can be made particularly excellent.

In the lens substrate of the present invention, it is preferable that the light shielding portion is made of a material containing a disperse dye.
This reduces the transmittance of light incident from the surface side provided with the lens portion while sufficiently preventing reflection of light incident from the surface side opposite to the side where the lens portion is provided. Can be prevented more effectively. As a result, light utilization efficiency, viewing angle characteristics, and contrast of displayed images can be made particularly excellent.

In the lens substrate of the present invention, it is preferable that the light shielding portion is formed using a coloring liquid containing a colorant and benzyl alcohol.
Thereby, the variation in the color density of the light shielding portion can be made particularly small, and the occurrence of color unevenness in the displayed image can be more reliably prevented. In addition, a light-shielding portion having a desired thickness and color density can be easily and reliably formed.

In the lens substrate of the present invention, it is preferable that the coloring liquid contains at least one compound selected from benzophenone compounds and benzotriazole compounds in addition to the colorant and the benzyl alcohol.
Thereby, the variation in the color density of the light-shielding portion can be made particularly small, and the occurrence of color unevenness in the displayed image can be more reliably prevented. In addition, a light-shielding portion having a desired thickness and color density can be formed more easily and reliably.

In the lens substrate of the present invention, the lens substrate is preferably a microlens substrate provided with a microlens as the lens portion.
Thereby, the viewing angle characteristic in each direction (for example, the up-down direction and the left-right direction) can be made particularly excellent.
In the lens substrate of the present invention, it is preferable that the lens substrate has a colored portion formed by staining near the surface of the lens portion.
Thereby, the contrast of the displayed image can be further improved.
In the lens substrate of the present invention, it is preferable that the color density of the colored portion is lower than the color density of the light shielding portion.
Thereby, it is possible to make the contrast of the displayed image particularly excellent while more effectively preventing the light use efficiency from being lowered.

The manufacturing method of the lens substrate of the present invention is a method of manufacturing the lens substrate of the present invention,
A photosensitive member made of a positive photosensitive material on the surface opposite to the side where the lens part is provided of the plate-like member having a plate shape and a large number of lens parts provided on one side. A photosensitive film forming step of forming a film;
A photosensitive step of exposing a part of the photosensitive film by irradiating the photosensitive film with light through the plate-like member to form a photosensitive part exposed;
A developing step for removing the photosensitive portion;
After the development step, an anti-dyeing agent applying step of applying an anti-dyeing agent for preventing dyeing to the surface side of the plate-like member provided with the photosensitive film;
A photosensitive film removing step of removing the photosensitive film remaining on the plate-like member;
It has the coloring liquid provision process which provides a coloring liquid in the surface side to which the said dyeing inhibiting agent was provided of the said plate-shaped member, It is characterized by the above-mentioned.
Accordingly, it is possible to provide a manufacturing method capable of manufacturing a lens substrate that is excellent in light utilization efficiency, excellent in viewing angle characteristics, and capable of displaying an image with excellent contrast.

The manufacturing method of the lens substrate of the present invention is a method of manufacturing the lens substrate of the present invention,
A photosensitive member made of a negative photosensitive material on the opposite side of the plate-like member from which the lens portion is provided. A photosensitive film forming step of forming a film;
A photosensitive step of exposing a part of the photosensitive film by irradiating the photosensitive film with light through the plate-like member to form a photosensitive part exposed;
A developing step for removing the photosensitive portion;
It has a coloring liquid application | coating process which provides a coloring liquid on the surface side in which the said photosensitive film | membrane of the said plate-shaped member was formed, It is characterized by the above-mentioned.
Accordingly, it is possible to provide a manufacturing method capable of manufacturing a lens substrate that is excellent in light utilization efficiency, excellent in viewing angle characteristics, and capable of displaying an image with excellent contrast.

In the manufacturing method of the lens substrate of this invention, it is preferable to have the photosensitive film | membrane removal process of removing the said photosensitive film | membrane remaining on the said plate-shaped member after the said coloring liquid provision process.
Thereby, the optical characteristics of the lens substrate can be made particularly excellent, and the durability and reliability of the lens substrate can be made particularly excellent.
The transmission screen of the present invention is characterized by including the lens substrate of the present invention.
Accordingly, it is possible to provide a transmissive screen that is excellent in light utilization efficiency, excellent in viewing angle characteristics, and capable of displaying an image with excellent contrast.

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.
Accordingly, it is possible to provide a transmissive screen that is excellent in light utilization efficiency, excellent in viewing angle characteristics, and capable of displaying an image with excellent contrast.
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 is excellent in light utilization efficiency, excellent in viewing angle characteristics, and capable of displaying an image with excellent contrast.

Hereinafter, a lens substrate, a method for manufacturing a lens substrate, a transmissive screen, and a rear projector of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
In the present invention, “substrate” and “plate” are concepts that include substantially no flexibility, relatively large thickness, sheet-like material, film-like material, and the like. Refers to that.
First, the configuration of the lens substrate and the transmission screen of the present invention will be described.

  1 is a schematic longitudinal sectional view showing a first embodiment of a lens substrate (microlens substrate) of the present invention, FIG. 2 is a schematic plan view of the lens substrate shown in FIG. 1, and FIG. 1 is a schematic longitudinal sectional view showing a first embodiment of a transmission screen according to the present invention including the lens substrate shown in FIG. 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 described later, and as shown in FIG. 1, a substrate body (plate member) provided with a plurality of microlenses (lens portions) 21. 2 has a function of preventing reflection of external light (external light absorption) on the light emission side of the microlens substrate 1 (that is, the surface opposite to the surface on which the microlens 21 is provided). A light shielding portion (colored portion) 22 that functions as a portion is provided. In the present embodiment, the microlens substrate 1 includes a substrate body 2 and a diffusion part (diffusion plate) 3.

Although the constituent material of the substrate body 2 is not particularly limited, it is mainly composed of a resin material and is composed of a transparent material having a uniform refractive index.
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 Various polyesters, polyesters, polyamides, polybutadienes, transpolyisoprenes, fluororubbers, chlorinated polyethylenes, and other thermoplastic elastomers, epoxy resins, phenol resins, urea resins, melamine resins, unsaturated polyesters, silicones Resins, urethane resins, etc., or copolymers, blends, polymer alloys, etc. mainly composed of these, are mentioned, and one or more of these are combined (for example, blend resins, polymer alloys, laminates) Among them, polystyrene, polycarbonate, polyethylene terephthalate, and acrylic resin are preferable from the viewpoint of transparency, and acrylic resin is particularly preferable among them. Acrylic resins have excellent transparency and are excellent in heat resistance, light resistance, workability, dimensional accuracy when molded, mechanical strength, etc., and as a constituent material of lens substrates (substrate body) Is preferred. In addition, although the acrylic resin has excellent characteristics as described above, there is a problem that coloring is difficult with a general method. According to this, a suitable colored part (light-shielding part 22) can be formed easily and reliably. Therefore, by using a substrate body mainly composed of an acrylic resin, it is possible to provide a lens substrate (microlens substrate) that is particularly excellent in various characteristics and excellent in reliability. In addition, acrylic resins are generally relatively inexpensive and advantageous from the standpoint of manufacturing costs.

  As an acrylic resin, for example, an acrylic resin having acrylic acid or a derivative thereof (for example, acrylic ester) as a constituent monomer, a methacrylic resin having a constituent monomer of methacrylic acid or a derivative thereof (for example, methacrylic ester), for example. Styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-acrylic acid ester-methacrylic acid ester copolymer, styrene-α-chloroacrylic acid methyl copolymer, styrene-acrylonitrile-acrylic acid A copolymer containing (meth) acrylic acid such as an ester copolymer or a derivative thereof as a constituent monomer can be used, and one or more selected from these can be used in combination.

Although the glass transition point (Tg) of the resin material which comprises the board | substrate body 2 is not specifically limited, It is preferable that it is 30-130 degreeC, It is more preferable that it is 45-120 degreeC, It is 70-110 degreeC. Is more preferable. When the glass transition point of the resin material constituting the substrate body 2 is a value within the above range, the durability of the microlens substrate 1 is sufficiently excellent, and details will be described later when the microlens substrate 1 is manufactured. It is possible to easily and reliably form the light shielding portion 22 as the colored portion as described below. When the substrate body 2 is composed of a plurality of types of resin components, the glass transition point of the resin material is the glass transition point for the mixture of these resin components, but the glass transition point as a mixture When measurement is difficult, the weighted average value of the glass transition points of each resin component can be adopted as the glass transition point of the resin material.
Moreover, in order to diffuse the incident light from the light source, the substrate main body 2 may contain, for example, polystyrene beads, glass beads, organic cross-linked polymers, etc. as a diffusing material, as necessary. Note that the diffusing material may be included in the entire resin (the entire substrate body 2), or may be included in only a part thereof.

  In the present embodiment, the microlens 21 has a vertical width (width in the vertical direction (length indicated by X in the figure)) in the plan view of the microlens substrate 1 and a horizontal width (indicated by Y in the figure). It has a flat shape (substantially elliptical, substantially bowl-shaped) smaller than the length)). 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. Moreover, the brightness of the projected image can be made higher.

  When the length in the minor axis direction (vertical direction) of the microlens 21 in plan view is X [μm] and the length in the major axis direction (lateral direction) is Y [μm], 0.10 ≦ X / It is preferable to satisfy the relationship of Y ≦ 0.99, more preferably satisfy the relationship of 0.50 ≦ X / Y ≦ 0.95, and satisfy the relationship of 0.60 ≦ X / Y ≦ 0.90 More preferably. 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) when viewed in plan is preferably 1 to 500 μm. When the length of the microlens 21 in the short axis direction (vertical width of the microlens 21) is a value within the above range, the viewing angle characteristics of the microlens substrate 1, the contrast of the projected image, and the brightness are particularly excellent. However, sufficient resolution can be obtained in the projected image. Further, when the length of the microlens 21 in the short axis direction (the width of the microlens 21) is a value within the above range, it is possible to effectively prevent the occurrence of inconvenience such as moire and the microlens substrate 1. Productivity can be further increased.

  Moreover, it is preferable that the length of the microlens 21 in the major axis direction (horizontal width of the microlens 21) in a plan view is 5 to 750 μm. When the length of the microlens 21 in the major axis direction (the width of the microlens 21) is a value within the above range, the viewing angle characteristics of the microlens substrate 1, the contrast of the projected image, and the luminance are particularly excellent. However, sufficient resolution can be obtained in the projected image. Further, when the length of the microlens 21 in the major axis direction is a value within the above range, it is possible to effectively prevent the occurrence of inconvenience such as moire and further increase the productivity of the microlens substrate 1. Can do.

  Further, the radius of curvature of the microlens 21 is preferably 2.5 to 375 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.

Moreover, it is preferable that the height of the microlens 21 (the height of the microlens 21 as a convex part) is 1-375 micrometers. When the height of the microlens 21 is within the above range, the viewing angle characteristics 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 adjacent second row 26 are preferably offset by a half pitch in the vertical direction. 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 90 to 100 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. The occupation ratio of the microlens 21 is a line segment connecting the center 211 of the microlens 21 when viewed in plan and the central portion of the portion adjacent to the microlens 21 where the microlens 21 is not formed. It can be determined as a ratio (L ₃ / L ₄ × 100 [%]) between the length L ₃ [μm] of the portion where the microlens 21 is formed and the length L ₄ [μm] of the line segment. (See FIG. 2).

  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 effect of having the microlens having the shape and arrangement method as described above, and a colored portion (light-shielding portion) described in detail later Synergistic effects with the effects of having a light emitting effect can be obtained, 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 is designed so that the focal point f is located in the vicinity of the surface on the emission side of the substrate body 2. That is, parallel light La (parallel light La from a Fresnel lens unit 5 described later) incident on the microlens substrate 1 from a substantially vertical direction is condensed by each microlens 21 of the microlens substrate 1 and The focal point f is set near the surface on the exit side of the main body 2.

  Further, as described above, the light shielding portion 22 is provided in the vicinity of the surface of the substrate body 2 on the light emission side (that is, the surface side opposite to the surface side (lens surface side) on which the microlenses 21 are provided). It has been. The light shielding unit 22 has a function of preventing reflection of external light (for example, external light incident unintentionally from the light emission side or the like). By having such a light shielding part, an image with excellent contrast can be obtained.

  By the way, in the conventional lens substrate, in order to improve the contrast, a film-shaped light-shielding layer having a predetermined thickness is formed on the surface of the substrate body (transparent sheet). However, in such a configuration, since the light-shielding layer has a predetermined thickness, a part of the light transmitted through the transparent sheet (light that is relatively refracted by the lens) is reflected on the side surface of the light-shielding layer. The light incident on the (thickness-direction surface) and absorbed by the light-shielding layer causes a problem that the light transmittance is lowered and the viewing angle characteristics are remarkably lowered (see FIG. 21).

  On the other hand, in the microlens substrate (lens substrate) 1 of the present invention, since the light shielding portion 22 is provided inside the substrate body 2, the function of preventing reflection of external light by the light shielding portion 22 is sufficiently exhibited. On the other hand, the light incident on the substrate main body (plate member) 2 from the light incident side and refracted by the microlens (lens portion) 21 can be sufficiently prevented from being blocked by the light shielding portion 22. In the conventional lens substrate as described above, since the light shielding layer is provided outside (on the surface) of the substrate body (transparent sheet), peeling at the interface between the transparent sheet and the light shielding layer (particularly, However, the microlens substrate (lens substrate) 1 of the present invention has a problem in durability and reliability of the lens substrate. Since the light shielding portion 22 is provided inside the substrate body (plate-like member) 2, the durability and reliability are excellent.

  The light shielding part 22 is provided by staining. Thus, for example, even if a part of light incident from the light incident side (light refracted by the microlens 21) is incident on the light shielding portion 22, the light is transmitted at a predetermined transmittance. The light can be transmitted, and the light transmittance is prevented from significantly decreasing. On the other hand, in the conventional lens substrate, the light-shielding portion has a light-shielding property that completely shields the incident light, so that the transmission of the light incident from the incident side is also blocked. Use efficiency, viewing angle characteristics, contrast of displayed images, and the like.

  The light shielding part 22 may be formed by dyeing, but is preferably dyed by dye. Thereby, even if it is a case where it injects into the light-shielding part 22, the said light can be permeate | transmitted with predetermined | prescribed transmittance | permeability and it is prevented that the transmittance | permeability of light falls remarkably. As a result, light utilization efficiency, viewing angle characteristics, and contrast of displayed images can be made particularly excellent.

  In addition, the light shielding part 22 may be provided at least in a part other than the part corresponding to the light condensing part of the microlens 21. For example, the light shielding part 22 may be provided in almost the entire light emission side. However, in the configuration shown in the figure, the microlens 21 is provided only in a portion other than the portion corresponding to the light collecting portion, and the light shielding portion 22 is not provided in the portion corresponding to the light collecting portion. That is, in the illustrated configuration, the portion corresponding to the light condensing part is not substantially dyed near the surface on the light emission side. As a result, light utilization efficiency, viewing angle characteristics, and contrast of displayed images can be made particularly excellent.

  As described above, the light shielding portion 22 may be provided almost in the vicinity of the surface on the light removal side. In such a case, the microlens (lens portion) 21 is provided in the vicinity of the surface. The part corresponding to the light condensing part preferably has a lower coloring density than other parts. Thereby, it is possible to more effectively prevent the light use efficiency, the viewing angle characteristics, and the contrast of the displayed image from being lowered.

  Further, as described above, since the light-shielding portion 22 is formed by dyeing the substrate body 2, the thickness variation in each part (particularly, the thickness not corresponding to the surface shape of the substrate body 2). Variation). Thereby, it is possible to prevent inconvenience such as color unevenness in the projected image. Further, by adopting a dyeing method as a method of forming the light shielding part (colored part) 22, the light shielding part (colored part) 22 having a sufficient light shielding property while forming a relatively thin thickness is suitably formed. be able to.

  In addition, although the light shielding part 22 is made of a material containing a colorant, it is provided by dyeing the substrate body 2, so that the main component is usually the substrate body 2 (microlens 21). Is the same as the main component. Accordingly, it is difficult for a sudden change in refractive index or the like to occur near the boundary between the light shielding portion 22 and other portions (non-colored portions). Accordingly, it is easy to design the optical characteristics of the microlens substrate 1 as a whole, and the optical characteristics of the microlens substrate 1 are stable and highly reliable.

  Although the thickness of the light shielding part 22 is not specifically limited, It is preferable that it is 0.1-50 micrometers, It is more preferable that it is 1-40 micrometers, It is further more preferable that it is 2-30 micrometers. When the thickness of the light-shielding portion 22 is a value within the above range, it is possible to display an image with better contrast while sufficiently improving light use efficiency and viewing angle characteristics.

  The color of the light shielding unit 22 is not particularly limited, but a colorant based on blue, mixed with red, brown, or yellow is used. The appearance is achromatic and black, and the balance of the three primary colors of light from the light source is controlled. It is preferable to selectively absorb or transmit light having a specific wavelength. As a result, reflection of external light is prevented, the color tone of the image formed by the light transmitted through the microlens substrate is accurately expressed, color coordinates are wide (the range of color tone expression is sufficiently wide), and deeper Since black can be expressed, the contrast can be made particularly excellent as a result.

  The microlens substrate 1 has a diffusion unit 3 having a function of diffusing light transmitted through the substrate body 2 on the light emission side of the substrate body 2. The diffusion unit 3 diffuses light by irregularly reflecting incident light (incident light). By having such a diffusing portion 3, the viewing angle characteristics can be further improved. In the present embodiment, the diffusing section 3 has a configuration in which a diffusing material is dispersed in a substantially transparent material (for example, acrylic resin, polycarbonate resin, etc.) having excellent light transmittance. As the diffusing material, for example, particulate (bead-shaped) silica, glass, resin (polystyrene resin, organic cross-linked polymer, etc.) and 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 3 is not specifically limited, It is preferable that it is 0.05-5 mm, It is more preferable that it is 0.7-4 mm, It is further more preferable that it is 1.0-3 mm. When the thickness of the diffusing portion 3 is a value within the above range, the viewing angle characteristic can be made particularly excellent while sufficiently improving the light utilization efficiency. On the other hand, if the thickness of the diffusing portion 3 is less than the lower limit value, the effect of providing the diffusing portion 3 may not be sufficiently exhibited. Further, when the thickness of the diffusing portion 3 exceeds the upper limit value, the probability (frequency) that the light (photon) collides with the diffusing material tends to increase rapidly, and quenching is likely to occur. There is a high possibility that light (photons) incident on the inside will return 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 5 and the microlens substrate 1 described above. The Fresnel lens unit 5 is installed on the light (image light) incident side, and the light transmitted through the Fresnel lens unit 5 is incident on the microlens substrate 1.
The Fresnel lens unit 5 has a prism-shaped Fresnel lens 51 formed in a substantially concentric shape on the exit side surface. The Fresnel lens unit 5 refracts image light from a projection lens (not shown) to produce 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 5 and becomes parallel light La. And this parallel light La injects into the surface side in which the micro lens 21 of the board | substrate body 2 was formed, is condensed by each micro lens 21, and the other surface side (surface side in which the light-shielding part 22 was provided) ). And after that, it injects in the spreading | diffusion part 3, and radiate | emits from the surface side (emission side) opposite to the incident side.
At this time, the light incident on the microlens substrate 1 is transmitted through the microlens substrate 1 with sufficient transmittance. The light emitted from the microlens substrate 1 is diffused and observed as a planar image by the observer.

Next, an example (first method) of manufacturing the microlens substrate 1 described above will be described.
FIG. 4 is a schematic longitudinal sectional view showing a member with a recess used for manufacturing a microlens substrate, and FIG. 5 is a schematic longitudinal sectional view showing a method for manufacturing the member with a recess shown in FIG. 6, 7, and 8 are schematic longitudinal sectional views illustrating an example (first method) of manufacturing the microlens substrate illustrated in FIG. 1. The manufacturing method of the microlens substrate shown in FIGS. 6 to 8 is a method of manufacturing a microlens substrate (substrate body) having a light shielding portion using a negative photosensitive material. In the following description, the lower side in FIGS. 6 to 8 is referred to as “(light) incident side” and the upper side is referred to as “(light) emission 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 concave portions (member with concave portions for forming microlenses) 6 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. Examples of the constituent material of the member 6 with recesses include soda glass, crystalline glass, quartz glass, lead glass, potassium glass, borosilicate glass, and alkali-free glass. Especially, as a constituent material of the member 6 with a recessed part, soda glass, crystalline glass (for example, neo-serum etc.), and an alkali free glass are preferable. Soda glass, crystalline glass, and alkali-free glass are easy to process, are relatively inexpensive, and are advantageous from the viewpoint of manufacturing cost.

  The member with recesses (member with recesses for forming microlenses) 6 includes a plurality of recesses (recesses for forming microlenses) 61 arranged in a manner corresponding to the arrangement method of the microlenses 21 (transferred positional relationship). ing. These recesses 61 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 recess while the microlens 21 is a protrusion. have.

  More specifically, in the present embodiment, the recess (microlens formation recess) 61 has a vertical width (width in the vertical direction) smaller than the horizontal width (width in the horizontal direction) when the member 6 with recesses is viewed in plan. It has a flat shape (substantially oval or substantially bowl-shaped). The concave portion 61 having such a shape is preferably used for manufacturing the microlens substrate 1 capable of effectively preventing the occurrence of inconvenience such as moire and having particularly excellent viewing angle characteristics. Can do.

  Further, when the length in the minor axis direction (longitudinal direction) of the recess 61 in plan view is X [μm] and the length in the major axis direction (lateral direction) is Y [μm], 0.10 ≦ X /Y≦0.99 is preferably satisfied, more preferably 0.50 ≦ X / Y ≦ 0.95 is satisfied, and 0.60 ≦ X / Y ≦ 0.90 is satisfied. It is more preferable to satisfy. By satisfying the relationship as described above, the effects as described above become more remarkable.

  Moreover, it is preferable that the length (width | variety of the recessed part 61) of the minor axis direction of the recessed part 61 when planarly viewed is 1-500 micrometers. When the length of the concave portion 61 in the minor 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 61 in the short 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 (member 6 with a recess) can be further increased.

  Moreover, it is preferable that the length of the major axis direction of the recessed part 61 when it planarly views is 5-750 micrometers. When the length of the concave portion 61 in the major 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 61 in the major 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 (member 6 with a recess) can be further increased.

  Moreover, it is preferable that the curvature radius of the recessed part 61 is 2.5-375 micrometers. When the radius of curvature of the recess 61 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 61 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 61 is 1-375 micrometers. When the depth of the recess 61 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 61 are arranged in a staggered pattern. By arranging the recesses 61 in this way, it is possible to effectively prevent inconveniences 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.

  Further, as described above, the recesses 61 are arranged in a staggered pattern when the member 6 with recesses is viewed in plan view, but are adjacent to the first row composed of the plurality of recesses 61. The second row is preferably shifted by a half pitch in the vertical direction. 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.

  In the above description, the concave portion 61 is described as having substantially the same shape (dimension) and arrangement method as the microlens 21 except that the concave portion 61 has a concave-convex relationship. In the case where the constituent material of the substrate main body 2 is easily contracted (when the composition constituting the substrate main body 2 contracts due to solidification or the like), the microlens 21 and the recess 61 are considered in consideration of the contraction rate and 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.
First, when manufacturing the member 6 with a recessed part, the board | substrate 7 is prepared.
The substrate 7 having a uniform thickness and having no deflection or scratches is preferably used. The substrate 7 is preferably one whose surface is cleaned by washing or the like.

<A1> A mask 8 having a large number of initial holes (openings) 81 is formed on the surface of the prepared substrate 7, and the back surface of the substrate 7 (the surface opposite to the surface on which the mask 8 is formed) A protective film 89 is formed (see a masking process, FIGS. 5A and 5B).
In particular, in the present embodiment, first, as shown in FIG. 5A, the back surface protective film 89 is formed on the back surface of the prepared substrate 7 and the mask forming film 4 is formed on the surface of the substrate 7 (mask). (Formation film forming step) Thereafter, as shown in FIG. 5B, the mask 8 is obtained by forming the initial hole 81 in the mask formation film 4 (initial hole formation step). The mask forming film 4 and the back surface protective film 89 can be formed simultaneously.

The mask forming film 4 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 formation film 4 (mask 8) is preferably configured so that the etching rate is substantially equal to or lower than that of the substrate 7.
From this point of view, as a material constituting the mask forming film 4 (mask 8), for example, a metal such as Cr, Au, Ni, Ti, Pt, an alloy containing two or more selected from these, Examples thereof include oxides (metal oxides), silicon, and resins.

In addition, the mask forming film 4 (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 4 (mask 8) is not particularly limited, but is a laminate having a layer mainly composed of chromium and a layer mainly composed of chromium oxide. Preferably there is. The mask forming film 4 having such a configuration can easily and reliably form an opening having a desired shape by irradiation with laser light as described later. The mask 8 obtained by using the mask forming film 4 has excellent stability with respect to etching solutions having various compositions (the substrate 7 can be more reliably protected in an etching process described later). . Further, when the substrate 7 is made of glass and the mask forming film 4 (mask 8) has the above-described structure, for example, in an etching process to be described later, in the etching process described later, A liquid containing ammonium fluoride can be suitably used. Since ammonium monohydrogen difluoride is not a poisonous deleterious substance, it can more reliably prevent the human body and the environment from being affected during work. Further, the mask forming film 4 (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 7 (particularly, adhesion in the etching process). ing. For this reason, by using the mask forming film 4 (mask 8) having the above-described configuration, the concave portion 61 having a desired shape can be easily and reliably formed.

  The method for forming the mask forming film 4 is not particularly limited, but the mask forming film 4 (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 4 can be suitably formed by, for example, a vapor deposition method or a sputtering method. When the mask forming film 4 (mask 8) is made of silicon, the mask forming film 4 can be suitably formed by, for example, a sputtering method or a CVD method.

  The thickness of the mask forming film 4 (mask 8) varies depending on the material constituting the mask forming film 4 (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 4 and the like. There is. In addition, when wet etching is performed in an etching process described later, the masked portion of the substrate 7 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 4 and the like, it becomes difficult to form the initial hole 81 that penetrates in the initial hole forming step described later, and the mask forming film 4 (mask Due to the internal stress of 8), the mask forming film 4 (mask 8) may be easily peeled off.

  The back surface protective film 89 is for protecting the back surface of the substrate 7 in the subsequent steps. By this back surface protective film 89, erosion, deterioration, etc. of the back surface of the substrate 7 are preferably prevented. The back surface protective film 89 has the same configuration as the mask forming film 4 (mask 8), for example. Therefore, the back surface protective film 89 can be provided in the same manner as the mask forming film 4 simultaneously with the formation of the mask forming film 4.

Next, as shown in FIG. 5B, a plurality of initial holes (openings) 81 are formed in the mask forming film 4 to obtain a 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 61 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. Further, by forming the initial hole 81 in the mask forming film 4 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 conventional photolithography method. 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 61 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 61 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 61 having the above-described shape can be more reliably formed in the etching process described later.
In addition to forming the initial hole 81 by irradiating the mask forming film 4 with laser light, for example, when forming the mask forming film 4 on the substrate 7, the foreign material is previously formed in a predetermined pattern on the substrate 7. Then, a defect may be positively formed in the mask forming film 4 by forming the mask forming film 4 thereon, and the defect may be used as the initial hole 81.

<A2> Next, as shown in FIG. 5C, the substrate 7 is etched using the mask 8 in which the initial holes 81 are formed, and a large number of recesses 61 are formed on the substrate 7 (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 7 covered with the mask 8 in which the initial holes 81 are formed, as shown in FIG. 5C, the substrate 7 is a portion where the mask 8 does not exist ( A large number of recesses 61 are formed on the substrate 7 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 61 are formed in a staggered pattern (in a staggered pattern) on the surface of the substrate 7. It will be arranged.

Further, when the wet etching method is used, the concave portion 61 can be suitably formed. If, for example, an etching solution containing ammonium monohydrogen difluoride is used as the etching solution, the substrate 7 can be etched more selectively, and the recess 61 can be suitably formed.
When the mask 8 (mask forming film 4) is mainly composed of chromium or chromium oxide, the hydrofluoric acid-based etchant is particularly preferably a liquid containing ammonium monohydrogen difluoride. 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 6 with a recessed part can be provided cheaply.

<A3> Next, as shown in FIG. 5D, the mask 8 is removed (mask removal step). At this time, by removing the back surface protective film 89 along with the removal of the mask 8, the member 6 with a recess is obtained.
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. The etching can be performed using a mixture containing an acid.

For example, you may perform a mold release process to the surface side in which the recessed part 61 of the member 6 with a recessed part is provided. Thereby, in the manufacturing method of the microlens substrate 1 described in detail later, the member 6 with the recesses can be easily removed while sufficiently preventing defects such as chipping from occurring on the microlens 21 of the substrate body 2. As a result, defects in the microlens 21 can be prevented in the final microlens substrate 1. Examples of the mold release treatment include formation of a film composed of a material having releasability such as silicone resin such as alkylpolysiloxane, fluorine resin such as polytetrafluoroethylene, and hexamethyldisilazane ([(CH ₃ ) Surface treatment with a silylating agent such as ₃ Si] ₂ NH), surface treatment with a fluorine-based gas, and the like.

As described above, as shown in FIGS. 5D and 4, the member 6 with recesses in which a large number of recesses 61 are formed in a staggered pattern on the substrate 7 is obtained.
The method for forming the plurality of recesses 61 arranged in a staggered pattern on the substrate 7 is not particularly limited, but the method as described above (by forming the initial holes 81 in the mask forming film 4 by laser irradiation). When the mask 8 is obtained and then etched using the mask 8 to form the recess 61 on the substrate 7, the following effects are obtained.
That is, by forming the initial hole 81 in the mask forming film 4 by laser light irradiation, the opening (with a predetermined pattern) can be easily and inexpensively compared with the case where the opening is formed by a conventional photolithography method. A mask having initial holes 81) can be obtained. Thereby, productivity improves and the member 6 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.

Next, a method of manufacturing the microlens substrate 1 using the above-described member 6 with a recess will be described.
<B1> First, as shown in FIG. 6A, on the surface of the member 6 having the recesses on the side where the recesses 61 are formed, the composition 23 having fluidity (for example, a softened resin material, Polymerization (uncured resin material) is applied, and a base film 24 is placed thereon, and the composition 23 is pressed by the flat plate (pressing member) 11 through the base film 24 (pressing step). .

  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 6 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 6 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 6 with recesses where the recesses 61 are formed, or in a state where the spacers are arranged on the member 6 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 is preferably 1 to 300 μm, more preferably 3 to 200 μm, and still more preferably 5 to 170 μm.

<B2> Next, the composition 23 is solidified (including curing (polymerization)) to obtain the substrate body 2 provided with the microlenses 21 (solidification step, see FIG. 6B).
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.

  <B3> Next, the flat plate 11 is removed from the formed substrate body 2 (pressing member removing step, see FIG. 6C). At this time, the recessed member 6 is not removed, but is kept in close contact with the substrate body 2. The flat plate 11 removed in this step can be repeatedly used for manufacturing the microlens substrate 1. Thereby, the stability of the quality of the microlens substrate 1 to be manufactured can be improved, and the manufacturing cost is advantageous.

  <B4> Next, a photosensitive film (negative photosensitive film) 91 made of a negative photosensitive material (for example, a photopolymer) is formed on the light-exiting surface of the substrate body 2 (photosensitive film). Step of forming (see FIG. 6D). Examples of a method for applying a photosensitive material to the surface of the substrate body 2 (a method for forming the photosensitive film 91) include dip coating, doctor blade, spin coating, brush coating, spray coating, electrostatic coating, electrodeposition coating, Various coating methods such as a roll coater can be used. Further, after film formation, heat treatment such as pre-bake treatment may be performed as necessary. Moreover, as a negative photosensitive material, photosensitive polyimide etc. are mentioned, for example.

<B5> Next, the recessed member 6 is removed from the substrate body 2 (recessed member removing step, see FIG. 7E). In addition, the removed member 6 with a recessed part can be repeatedly used for manufacture of the board | substrate body 2 (micro lens board | substrate 1), and the stability of the quality of the manufacturing cost surface and the board | substrate body 2 (micro lens board | substrate 1) manufactured are stabilized. It is also advantageous for enhancing the performance.
<B6> Next, the substrate body 2 covered with the photosensitive film 91 is irradiated with light for exposure (photosensitive) from the surface side from which the recessed member 6 is removed (photosensitive process; FIG. 7F). reference). Thereby, the irradiated light is condensed by the microlens 21. And the photosensitive film | membrane 91 provided in the site | part corresponding to a condensing part hardens | cures, and the photosensitive film | membrane 91 provided in the other site | part does not harden | cure.

<B7> Next, an uncured portion of the photosensitive film 91 is removed (development process; see FIG. 7G). Thereby, the mask 92 which covers the site | part corresponding to the condensing part of the micro lens 21 on the surface by the side of the board | substrate body 2 is obtained.
<B8> Next, a colored liquid (staining liquid) is applied to the side of the substrate body 2 covered with the mask 92 that is covered with the mask 92 (colored liquid applying step; see FIG. 7H). As a result, the substrate body 2 is selectively stained only in the vicinity of the surface of the exit surface side that is not covered with the mask 92, and the light shielding portion 22 is formed. At this time, the microlens surface is preferably protected with a protective film or the like, but the lens surface described in detail in the second embodiment can be dyed at the same time without protection.

  The color liquid may be any, but in the present embodiment, it contains a colorant and benzyl alcohol. The present inventor has found that by using such a colored liquid, the substrate body can be dyed easily and reliably. In particular, it is possible to easily and reliably dye a substrate body made of a material that has been difficult to be colored, such as an acrylic resin. This is considered to be due to the following reasons.

  That is, by using a colored liquid containing benzyl alcohol, the benzyl alcohol in the colored liquid penetrates and diffuses into the substrate body, loosens the bonds (intermolecular bonds) of the molecules constituting the substrate body, and the colorant enters. To secure space for Then, by replacing the benzyl alcohol with the colorant, the colorant is held in the space (which can be compared to a seat for the colorant (colored seat)), and the substrate body is dyed.

Further, by using the coloring liquid as described above, it is possible to easily and reliably form the light shielding portion 22 having a uniform thickness and a uniform coloring density. In particular, even if the region to be colored has a large area, the light shielding portion 22 can be formed with a uniform thickness (without color unevenness).
Examples of the method for applying the coloring liquid include various application methods such as doctor blade, spin coating, brush coating, spray coating, electrostatic coating, electrodeposition coating, textile printing, and roll coater, and the substrate body is immersed in the coloring liquid. Although methods, such as dipping, are mentioned, Especially, dipping (especially dip dyeing) is preferable. Thereby, the light shielding part 22 (particularly, the light shielding part 22 having a uniform thickness and a uniform color density) can be formed easily and reliably. In particular, when the coloring liquid is applied by dip dyeing, the substrate body 2 to which the coloring liquid is applied is made of a material that is difficult to be colored by a conventional method such as an acrylic resin. Even if it is a thing, it can be colored (dyed) easily and reliably. This is presumably because the dye that can be used for the dip dyeing has a high affinity with the ester group (ester bond) of the acrylic resin or the like.

  The step of applying the coloring liquid (coloring liquid applying step) is preferably performed under the following temperature conditions. That is, when the glass transition point of the resin material constituting the substrate body provided for the coloring liquid application step is Tg [° C.], the treatment temperature in the coloring liquid application step is preferably (Tg + 30) ° C. or less. Tg−70) to (Tg + 30) ° C. is more preferable, (Tg−60) to (Tg + 20) ° C. is more preferable, and (Tg−60) to (Tg) ° C. is most preferable. By applying the coloring liquid under such conditions, it is possible to form a light-shielding portion with a uniform thickness and with suppressed unevenness in coloring density. On the other hand, when the processing temperature in the coloring liquid application process exceeds the upper limit, the softening of the resin starts abruptly, and the part that has started to soften significantly relieves the molecular bond of the substrate body, so that the coloring liquid is accelerated. Due to the impregnation, a large difference is caused in the degree of impregnation of the colored liquid in the substrate surface. For this reason, the variation in the density of the light-shielding portion formed is rapidly increased, resulting in uneven color density. From the point where Tg is exceeded, the softening phenomenon of the resin itself starts with the molecular bond of the substrate body in the whole substrate, the molecular bond of the substrate body is loosened and the colored liquid is easily impregnated, but there is a difference in the degree of softening. Since it is not yet large, it is not so noticeable that the variation in the color density is visible. However, if the upper limit value is exceeded, a difference in softening level starts to occur in the surface, so that variations in color density can be visually recognized. In addition, if the processing temperature in the coloring liquid application step is too high, the substrate main body may be deformed, and desired optical characteristics may not be obtained in the lens substrate, or significant dyeing unevenness may occur. Moreover, when the process temperature in a coloring liquid provision process is too low, the tendency of the efficiency of formation of a light-shielding part will fall.

Moreover, it is preferable that the processing temperature in a coloring liquid provision process is 40-100 degreeC. When the treatment temperature is less than the lower limit value, the dyeing speed tends to decrease remarkably. If the processing temperature exceeds the upper limit, the resin of the substrate may be deformed, the shape of the molded lens may be deformed, the optical characteristics may be affected, and the image quality may be degraded.
Moreover, you may perform the process of providing a coloring liquid in the state (pressurized state) which raised atmospheric pressure, for example. Thereby, the penetration | invasion to the inside of the substrate main body 2 of a coloring liquid can be accelerated | stimulated, As a result, the light-shielding part 22 can be formed efficiently in a short time.

The application of the coloring liquid may be repeated a plurality of times as necessary (for example, when the thickness of the light shielding portion 22 to be formed is relatively large).
Further, after the coloring liquid is applied, a heat treatment such as heating or cooling, light irradiation, pressurization of the atmosphere, or decompression may be performed as necessary. Thereby, fixation (stabilization) of the light shielding part 22 can be promoted.

Hereinafter, the coloring liquid used in this step will be described in more detail.
Although the content rate of the benzyl alcohol in a coloring liquid is not specifically limited, It is preferable that it is 0.01-10.0 wt%, it is more preferable that it is 0.05-8.0 wt%, 0.1-5 More preferably, it is 0.0 wt%. When the content of benzyl alcohol is a value within the above range, it is possible to more effectively prevent an adverse effect on the substrate body 2 on which the light shielding portion 22 is to be formed (for example, deterioration of the constituent materials of the substrate body 2). The suitable light shielding part 22 can be formed easily and reliably.

  The colorant contained in the coloring liquid may be any dye or pigment, but is preferably a dye, more preferably a disperse dye and / or a cationic dye, and a disperse dye. More preferably. As a result, it is possible to efficiently form the light shielding portion 22 while sufficiently preventing an adverse effect on the substrate body 2 on which the light shielding portion 22 is to be formed (for example, deterioration of the constituent material of the substrate body 2). In particular, even if the substrate body 2 to which the coloring liquid is applied is made of a material that is difficult to be colored by a conventional method such as an acrylic resin, it is easily and reliably colored ( Dyeing). This is considered to be because the colorant as described above is more easily dyed because the ester group (ester bond) of the acrylic resin or the like is used as a dyeing seat.

  Moreover, although the coloring liquid used by this embodiment contains a coloring agent and benzyl alcohol at least, it is preferable that a surfactant is further included. Thus, the coloring agent can be stably and uniformly dispersed even in the presence of benzyl alcohol, and the substrate body 2 to which the coloring liquid is applied is colored by a conventional method such as an acrylic resin. Even those made of materials that are difficult to do can be colored (dyed) easily and reliably. Examples of the surfactant include nonionic (nonionic), anionic surfactant, cationic surfactant, and amphoteric surfactant. Nonionic (nonionic) surfactants include, for example, ether surfactants, ester surfactants, ether ester surfactants, nitrogen-containing surfactants, and more specifically, , Polyvinyl alcohol, carboxymethyl cellulose, polyethylene glycol, acrylic acid ester, methacrylic acid ester and the like. Examples of the anionic surfactant include various rosins, various carboxylates, various sulfates, various sulfonates, various phosphates, etc. More specifically, gum rosin, polymerized rosin , Heterogenized rosin, maleated rosin, fumarized rosin, maleated rosin pentaester, maleated rosin glycerin ester, tristearate (for example, metal salt such as aluminum salt), distearate (for example, aluminum salt) , Metal salts such as barium salts), stearates (eg, metal salts such as calcium salts, lead salts, zinc salts), linolenate salts (eg, cobalt salts, manganese salts, lead salts, zinc salts, etc.) Metal salts, etc.), octanoates (eg, metal salts such as aluminum salts, calcium salts, cobalt salts, etc.), oleates (examples) For example, calcium salts, metal salts such as cobalt salts, etc.), palmitates (eg, metal salts such as zinc salts), naphthenates (eg, calcium salts, cobalt salts, manganese salts, lead salts, zinc salts, etc.) Metal salts, etc.), resinates (eg, metal salts such as calcium salt, cobalt salt, manganese lead salt, zinc salt etc.), polyacrylates (eg metal salts such as sodium salt, etc.), polymethacrylic acid Salt (for example, metal salt such as sodium salt), polymaleate (for example, metal salt such as sodium salt), acrylic acid-maleic acid copolymer salt (for example, metal salt such as sodium salt), cellulose , Dodecylbenzene sulfonate (eg, sodium salt), alkyl sulfonate, polystyrene sulfonate (eg, metal salt such as sodium salt), alkyl diphenyl ester, etc. Terujisuruhon salts (e.g., metal salts such as sodium salt), and the like. Examples of the cationic surfactant include various ammonium salts such as a primary ammonium salt, a secondary ammonium salt, a tertiary ammonium salt, and a quaternary ammonium salt. More specifically, (mono) Examples thereof include alkylamine salts, dialkylamine salts, trialkylamine salts, tetraalkylamine salts, benzalkonium salts, alkylpyridium salts, imidazolinium salts, and the like. Examples of amphoteric surfactants include various betaines such as carboxybetaine and sulfobetaine, various aminocarboxylic acids, and various phosphate esters.

  Further, for example, the coloring liquid may contain at least one compound selected from benzophenone compounds and benzotriazole compounds. Thereby, the effects as described above are exhibited more significantly. More specifically, for example, the substrate main body 2 can be dyed more easily and reliably. In particular, a substrate made of a material that is difficult to be colored by a conventional coloring method, such as an acrylic resin. The main body 2 can also be dyed easily and reliably. Moreover, even when the processing temperature in this step is lower, a suitable light shielding portion 22 can be formed efficiently in a short time. This includes at least one compound selected from a benzophenone compound and a benzotriazole compound by using at least one compound selected from a benzophenone compound and a benzotriazole compound in combination with benzyl alcohol; It is considered that benzyl alcohol acts in a complementary manner, and as a result, a remarkable effect (synergistic effect) is exhibited by using these in combination. More specifically, it is considered that this is due to the following reason (mechanism).

  That is, first of all, the benzyl alcohol in the coloring liquid loosens the bonds of the resin molecules constituting the substrate body, and secures a space for other molecules to enter. Secondly, at least one compound selected from benzophenone compounds and benzotriazole compounds penetrates into this space and diffuses deeply in preference to the colorant. This is because benzophenone compounds and benzotriazole compounds, like benzyl alcohol, relax the bonding of the resin molecules that make up the substrate body and secure a space for other molecules to enter. This is because the space secured by alcohol is used to deepen and widen the space. Colorants do not have this function. Third, in parallel with the second action, the colorant enters and is retained in the space. Alternatively, it is partially substituted with a benzophenone compound and a benzotriazole compound. Thus, by using a benzophenone compound or a benzotriazole compound in combination with benzyl alcohol, the colorant can be diffused into the substrate body efficiently, deeply, in a relatively short time, and uniformly dyed. It becomes possible.

  Examples of the benzophenone compounds include compounds having a benzophenone skeleton as represented by the following formula (I) or other limit structural formulas corresponding thereto, or tautomers thereof (hereinafter simply referred to as “formula (I)”. Or a derivative thereof (eg, an addition reaction product, a substitution reaction product, a reduction reaction product, an oxidation reaction product, etc.).

  Examples of such compounds include benzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2 ′, 4,4. Examples include '-tetrahydroxybenzophenone, 2-hydroxy-4-octylbenzophenone, 4-benzyloxy-2-hydroxybenzophenone, benzophenone anil, benzophenone oxime, and benzophenone chloride (α, α'-dichlorodiphenylmethane). Among them, a compound having a benzophenone skeleton represented by the above formula (I) is preferable, and 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone. Is more preferable. By using such a benzophenone-based compound, the effects as described above appear more remarkable. In addition, structural formulas (chemical formulas) of 2,2′-dihydroxy-4,4′-dimethoxybenzophenone and 2,2 ′, 4,4′-tetrahydroxybenzophenone are respectively represented by the following formula (II) and formula Shown as (III).

  The benzotriazole compounds include compounds having a benzotriazole skeleton as represented by the following formula (IV) or other limit structural formulas corresponding thereto, or tautomers thereof (hereinafter simply referred to as “formulas”). Or a derivative thereof (for example, an addition reaction product, a substitution reaction product, a reduction reaction product, an oxidation reaction product, or the like) can be used.

  Examples of such compounds include benzotriazole, 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole, 2- (2-hydroxy-4-octyloxyphenyl) -2H-benzotriazole, and the like. Can be mentioned. Among them, a compound having a benzotriazole skeleton represented by the above formula (IV) is preferable, and 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole, 2- (2-hydroxy-4-) Octyloxyphenyl) -2H-benzotriazole is more preferred. By using such a benzotriazole-based compound, the effects as described above appear more remarkable. The structural formulas (chemical formulas) of 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole and 2- (2-hydroxy-4-octyloxyphenyl) -2H-benzotriazole are respectively shown. The following formula (V) and formula (VI) are shown.

The colored liquid may contain at least one compound selected from the above-mentioned benzophenone compounds and benzotriazole compounds, but two or more compounds (particularly, one or more benzophenone compounds) may be used. A compound and one or more benzotriazole-based compounds) may be included. As a result, these compounds act in a complementary manner, and these compounds act in a complementary manner with benzyl alcohol, so that the above-described effects appear even more remarkable.
Further, the same effect can be obtained by immersing in a pretreatment liquid containing at least one compound selected from the above benzophenone compounds and benzotriazole compounds and benzyl alcohol and then immersing in the coloring liquid. .

  When the coloring liquid or pretreatment liquid contains at least one compound selected from benzophenone compounds and benzotriazole compounds, the total content of the benzophenone compounds and benzotriazole compounds in the coloring liquid or pretreatment liquid Is not particularly limited, but is preferably 0.001 to 10.0 wt%, more preferably 0.005 to 5.0 wt%, and still more preferably 0.01 to 3.0 wt%. . When the sum of the content ratios of the benzophenone compound and the benzotriazole compound is within the above range, an adverse effect on the substrate body 2 on which the light shielding portion 22 is to be formed (for example, deterioration of constituent materials of the substrate body 2) It is possible to easily and surely form a suitable light shielding portion 22 while preventing the above effectively.

  Further, when the content of benzyl alcohol in the coloring liquid or the pretreatment liquid is X [wt%] and the total content of the benzophenone compound and the benzotriazole compound is Y [wt%], 0.001 ≦ The relationship X / Y ≦ 10000 is preferably satisfied, the relationship 0.05 ≦ X / Y ≦ 1000 is more preferable, and the relationship 0.25 ≦ X / Y ≦ 500 is further satisfied. preferable. By satisfying the relationship as described above, the synergistic effect of combining the benzophenone compound and / or the benzotriazole compound with benzyl alcohol is more significantly exhibited, and the substrate body 2 on which the light shielding portion 22 is to be formed. It is possible to easily and surely form a suitable light-shielding portion 22 at a high speed while more effectively preventing the occurrence of adverse effects on the substrate (for example, deterioration of the constituent materials of the substrate body 2).

<B9> Next, the mask 92 is removed (mask removal step; see FIG. 8I). Thereby, the optical characteristics of the microlens substrate 1 (substrate body 2) can be made particularly excellent, and the durability and reliability of the microlens substrate 1 (substrate body 2) should be made particularly excellent. Can do.
<B10> Next, the diffusion part 3 is formed on the side of the substrate body 2 on which the light shielding part 22 is provided (diffusion part forming step; see FIG. 8 (j)). The diffusion part 3 is preferably formed by bonding a sheet material made of the material as described above (the constituent material of the diffusion part 3) to the surface side of the substrate body 2 where the light shielding part 22 is provided. be able to. Thereby, the microlens substrate 1 is obtained.

Next, another example (second method) of manufacturing the microlens substrate 1 described above will be described. In this method (second method), the microlens substrate 1 (substrate body 2) is manufactured using the recessed member 6 in the same manner as the above-described method (first method).
9, 10 and 11 are schematic longitudinal sectional views showing another example (second method) of the method for manufacturing the microlens substrate shown in FIG. The manufacturing method of the microlens substrate shown in FIGS. 9 to 11 is a method of manufacturing a microlens substrate (substrate body) having a light shielding portion using a positive photosensitive material. In the following description, the lower side in FIGS. 9 to 11 is referred to as “(light) incident side”, and the upper side is referred to as “(light) emission side”.

Hereinafter, the second method will be described focusing on differences from the above-described method (first method), and description of similar matters will be omitted.
<B1 ′> Same as <B1> in the first method described above (see FIG. 9A).
<B2 ′> Same as <B2> in the first method described above (see FIG. 9B).
<B3 ′> Same as <B3> in the first method described above (see FIG. 9C).

  <B4 ′> Next, a photosensitive film (positive photosensitive film) 95 made of a positive photosensitive material (for example, photopolymer) is formed on the surface on the emission side of the substrate body 2 (photosensitive). Film formation step (see FIG. 9D). Examples of a method for applying a photosensitive material to the surface of the substrate body 2 (a method for forming the photosensitive film 95) include dip coating, doctor blade, spin coating, brush coating, spray coating, electrostatic coating, electrodeposition coating, Various coating methods such as a roll coater can be used. Further, after film formation, heat treatment such as pre-bake treatment may be performed as necessary. Moreover, as a positive photosensitive material, photosensitive polyimide etc. are mentioned, for example.

<B5 '> Next, the recessed member 6 is removed from the substrate body 2 (recessed member removing step, see FIG. 10E). In addition, the removed member 6 with a recessed part can be repeatedly used for manufacture of the board | substrate body 2 (micro lens board | substrate 1), and the stability of the quality of the manufacturing cost surface and the board | substrate body 2 (micro lens board | substrate 1) manufactured are stabilized. It is also advantageous for enhancing the performance.
<B6 ′> Next, the substrate body 2 covered with the photosensitive film 95 is irradiated with light for exposure (photosensitive) from the surface side from which the recessed member 6 is removed (photosensitive process; FIG. 10 (f). )reference). Thereby, the irradiated light is condensed by the microlens 21. And the photosensitive film | membrane 95 provided in parts other than the part corresponding to a condensing part hardens | cures, and the photosensitive film | membrane 95 provided in parts other than the part corresponding to a condensing part does not harden | cure.

<B7 ′> Next, an uncured portion of the photosensitive film 95 is removed (development process; see FIG. 10G). As a result, a mask 96 that covers a portion other than the portion corresponding to the light condensing portion of the microlens 21 on the surface on the emission side of the substrate body 2 is obtained.
<B8 ′> Next, a dyeing preventing agent 99 for preventing the dyeing of the substrate main body 2 by the coloring liquid is applied to the side of the substrate main body 2 covered with the mask 96 (dyeing agent applying step. FIG. 10 (h). )reference). Examples of the anti-dyeing agent 99 include various types of glue, a water-repellent material such as a fluorine-based resin, a silicone-based resin, and a resin formed as a dyeing sacrificial layer (a substitute layer for dyeing the substrate surface is used as a sacrificial layer) For example).

<B9 ′> Next, the mask 96 is removed (mask removal step; see FIG. 11I). As a result, the portion of the substrate body 2 that has been covered with the mask 96 is exposed, and the other portions are covered with the anti-dyeing agent 99.
<B10 '> Next, a coloring liquid is applied to the substrate body 2 partially covered with the dyeing preventive agent 99 (coloring liquid applying step, see FIG. 11 (j)). As a result, the substrate body 2 is selectively dyed only in the vicinity of the surface of the exit surface side that is not covered with the anti-dyeing agent 99, and the light shielding portion 22 is formed. At this time, the microlens surface is preferably protected with a protective film or the like, but the lens surface described in detail in the second embodiment can be dyed at the same time without protection.
This step can be performed in the same manner as <B8> in the above-described method (first method).

<B11 ′> Next, the anti-dyeing agent 99 is removed (dyeing agent removing step, see FIG. 11 (k)). Thereby, the optical characteristics of the microlens substrate 1 (substrate body 2) can be made particularly excellent, and the durability and reliability of the microlens substrate 1 (substrate body 2) should be made particularly excellent. Can do.
<B12 ′> Next, similarly to <B9> in the above-described method (first method), the diffusion portion 3 is formed on the side of the substrate body 2 on which the light shielding portion 22 is provided (the diffusion portion). Step of forming (see FIG. 11 (l)). Thereby, the microlens substrate 1 is obtained.

Next, a lens substrate and a transmissive screen according to a second embodiment of the present invention will be described.
FIG. 12 is a schematic longitudinal sectional view showing a second embodiment of the lens substrate (microlens substrate) of the present invention, and FIG. 13 shows a second embodiment of the transmission screen of the present invention including the lens substrate shown in FIG. It is a typical longitudinal cross-sectional view which shows 2 embodiment. In the following description, the left side in FIGS. 12 and 13 is referred to as “(light) incident side”, and the right side is referred to as “(light) emission side”.

Hereinafter, the lens substrate and the transmissive screen according to the second embodiment will be described with a focus on differences from the above-described embodiments, and descriptions of similar matters will be omitted.
As shown in FIG. 1, in the microlens substrate 1 of the present embodiment, the substrate body 2 has the light shielding portion (first colored portion) 22 as described above near the surface on the light incident side, and the microlens. A colored portion (second colored portion) 27 is provided near the surface of the (lens portion) 21 (near the surface on the light incident side). The coloring unit 27 can sufficiently transmit light incident from the incident side, and external light (for example, external light incident unintentionally from the light emitting side or the like) is reflected on the light emitting side. It has a function to prevent. By having such a colored portion 27, an image with better contrast can be obtained. In particular, by having the light-shielding part (first colored part) 22 and the colored part (second colored part) 27, these act synergistically, and the light utilization efficiency and viewing angle characteristics are particularly excellent. It is possible to display an image with higher contrast. Further, by including the colored portion 27, it is possible to absorb external light sufficiently efficiently even if the color density of the light shielding portion 22 is relatively low. In other words, with the configuration as in the present embodiment, the color density of the light shielding portion 22 can be made relatively low, and as a result, the light utilization efficiency and the viewing angle characteristics are particularly excellent, and the display The contrast of the displayed image can be made particularly excellent. Such a colored portion 27 can be formed by a method similar to that for the light shielding portion 22, as will be described in detail later.

The coloring concentration of the coloring portion 27 is not particularly limited, but is preferably lower than the coloring concentration of the light shielding portion 22. Thereby, it is possible to make the contrast of the displayed image particularly excellent while more effectively preventing the light use efficiency from being lowered.
In the present embodiment, the concentration of the colored portion 27 is not particularly limited, but is preferably 40 to 85% in terms of Y value (D65 / 2 ° field of view), more preferably 45 to 75%, and more preferably 50 to More preferably, it is 70%. When the density of the coloring portion 27 is a value within the above range, the contrast of an image formed by light transmitted through the microlens substrate 1 (substrate body 2) can be made particularly excellent.

  The color of the colored portion 27 is not particularly limited, but a colorant based on blue, mixed with red, brown, or yellow is used. The appearance is achromatic and black, and the balance of the three primary colors of light from the light source is controlled. It is preferable to selectively absorb or transmit light having a specific wavelength. As a result, reflection of external light is prevented, the color tone of the image formed by the light transmitted through the microlens substrate is accurately expressed, color coordinates are wide (the range of color tone expression is sufficiently wide), and deeper Since black can be expressed, the contrast can be made particularly excellent as a result.

Next, an example (first method) of manufacturing the microlens substrate 1 of the present embodiment will be described. In this method, similarly to the method of the first embodiment described above, the microlens substrate 1 (substrate body 2) is manufactured using the recessed member 6.
14, FIG. 15 and FIG. 16 are schematic longitudinal sectional views showing an example (first method) of manufacturing the microlens substrate shown in FIG. The microlens substrate manufacturing method shown in FIGS. 14 to 16 is a method of manufacturing a microlens substrate (substrate body) having a light-shielding portion using a negative photosensitive material. In the following description, the lower side in FIGS. 14 to 16 is referred to as “(light) incident side” and the upper side is referred to as “(light) emission side”.

Hereinafter, the method (first method) of the present embodiment will be described focusing on the differences from the method of the above-described embodiment (first method), and description of similar matters will be omitted. .
<B1 ″> Same as <B1> in the method of the first embodiment (first method) (see FIG. 14A).
<B2 ″> Same as <B2> in the method of the first embodiment (first method) (see FIG. 14B).

<B3 ″> Same as <B3> in the method (first method) of the first embodiment (see FIG. 14C).
<B4 ″> Same as <B4> in the method (first method) of the first embodiment (see FIG. 14D).
<B5 ″> Same as <B5> in the method of the first embodiment (first method) (see FIG. 15E).

<B6 ″> Same as <B6> in the method of the first embodiment (first method) (see FIG. 15F).
<B7 ″> Same as <B7> in the method (first method) of the first embodiment (see FIG. 15G).
<B8 ''> Same as <B8> in the method (first method) of the first embodiment (first colored liquid application step; see FIG. 15 (h)).

  <B9 ''> Next, a colored liquid is applied to the surface of the substrate body 2 on which the microlenses 21 are provided (second colored liquid applying step, see FIG. 16 (i)). Thereby, in the substrate body 2, a colored portion (second colored portion) 27 is formed near the surface of the microlens 21. This step can be performed, for example, by the same method and conditions as the above-described <B7 ″>. Further, the composition of the coloring liquid used in this step and the conditions for applying the coloring liquid (for example, the processing temperature, the processing time, etc.) are different from those described above for <B7 ″>, so that the light can be shielded easily and reliably. The coloring density, thickness, and the like of the portion (first coloring portion) 22 and the coloring portion (second coloring portion) 27 can be made different. At this time, the surface on which the light shielding portion 22 is formed may be dyed at the same time or may be protected.

<B10 ″> Same as <B9> in the method of the first embodiment (first method) (see FIG. 16J).
<B11 ″> Same as <B10> in the method of the first embodiment (first method) (see FIG. 16K).
The microlens substrate 1 of this embodiment is obtained by the method as described above.

Next, another example (second method) for manufacturing the microlens substrate 1 of the present embodiment will be described.
17, 18, and 19 are schematic longitudinal sectional views showing another example (second method) of the method for manufacturing the microlens substrate shown in FIG. The manufacturing method of the microlens substrate shown in FIGS. 17 to 19 is a method of manufacturing a microlens substrate (substrate body) having a light shielding portion using a positive photosensitive material. In the following description, the lower side in FIGS. 17 to 19 is referred to as “(light) incident side” and the upper side is referred to as “(light) emission side”.

Hereinafter, the second method of the present embodiment will be described focusing on differences from the method of the above-described embodiment (second method), and description of similar matters will be omitted.
<B1 ′ ″> Same as <B1 ′> in the method (second method) of the first embodiment (see FIG. 17A).
<B2 ′ ″> Same as <B2 ′> in the method of the first embodiment (second method) (see FIG. 17B).

<B3 ′ ″> Same as <B3 ′> in the method of the first embodiment (second method) (see FIG. 17C).
<B4 ′ ″> Same as <B4 ′> in the method (second method) of the first embodiment (see FIG. 17D).
<B5 ′ ″> Same as <B5 ′> in the method (second method) of the first embodiment (see FIG. 18E).

<B6 ′ ″> Same as <B6 ′> in the method of the first embodiment (second method) (see FIG. 18F).
<B7 ′ ″> Same as <B7 ′> in the method (second method) of the first embodiment (see FIG. 18G).
<B8 ′ ″> Same as <B8 ′> in the method (second method) of the first embodiment (see FIG. 18H).

<B9 ′ ″> Same as <B9 ′> in the method (second method) of the first embodiment (see FIG. 19I).
<B10 ′ ″> Same as <B10 ′> in the method of the first embodiment (second method) (first colored liquid application step; see FIG. 19 (j)).
<B11 ′ ″> Next, a colored liquid is applied to the surface side of the substrate body 2 on which the microlenses 21 are provided (second colored liquid applying step; see FIG. 19 (k)). Thereby, in the substrate body 2, a colored portion (second colored portion) 27 is formed near the surface of the microlens 21. This step can be performed, for example, by the same method and conditions as described above for <B10 ′ ″>. In addition, by making the composition of the coloring liquid used in this step and the coloring liquid application conditions (for example, processing temperature, processing time, etc.) different from <B10 ′ ″> described above, it can be easily and reliably performed. The light-shielding part (first colored part) 22 and the colored part (second colored part) 27 can be different in color density, thickness, and the like. At this time, the surface on which the light shielding portion 22 is formed may be dyed at the same time or may be protected.

<B12 ′ ″> Same as <B11 ′> in the method (second method) of the first embodiment (see FIG. 19L).
<B13 ′ ″> Same as <B12 ′> in the method (second method) of the first embodiment (see FIG. 19M).
The microlens substrate 1 of this embodiment is obtained by the method as described above.

A rear projector using the transmission screen will be described below.
FIG. 20 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 transmissive screen 10 as described above, it is possible to obtain an image with high brightness and excellent contrast. Further, since the microlens substrate 1 (transmission type screen 10) as described above is provided, the viewing angle characteristics and the like 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, the transmissive screen, and the rear projector can be replaced with any structure that can exhibit the same function.
Moreover, in embodiment mentioned above, although demonstrated as what uses a plate-shaped (or film-shaped) member (member with a recessed part) as a member with a recessed part, a member with a recessed part is not limited to the thing of such a form, For example, it may have a roll shape and have a recess on its peripheral surface.

Moreover, although embodiment mentioned above demonstrated as what uses the coloring liquid containing a coloring agent and benzyl alcohol as a coloring liquid, the coloring liquid used by this invention is not limited to such a thing. For example, a coloring liquid that does not contain benzyl alcohol may be used.
Further, prior to the coloring liquid application step, for example, pretreatment may be performed on the substrate body for the purpose of improving the ease of dyeing of the substrate body. Examples of such pretreatment include a treatment of applying a liquid containing at least one selected from the group consisting of benzyl alcohol, benzophenone, and benzotriazole to the substrate body.

Moreover, each process of the manufacturing method of a lens substrate is not limited to what is performed in the order as mentioned above, You may change the order of each process.
In the second embodiment described above, the coloring portion (second coloring portion) is described as being provided on the entire surface of the lens substrate on the light incident side. However, the coloring portion (second coloring portion) is It may be provided only on a part of the light incident surface side. For example, the coloring part (second coloring part) may be provided selectively only near the top of the lens part. As a result, it is possible to display an image with better contrast while making the light utilization efficiency and viewing angle characteristics particularly excellent.

In the above-described embodiment, the microlens in the microlens substrate and the concave portion in the member with concave portions are described as having an elliptical shape when viewed in plan. For example, it may be a circle, a substantially square, a substantially hexagon, or the like.
In the above-described embodiment, the microlenses in the microlens substrate and the concave portions in the member with concave portions are described as being arranged in a staggered manner, but the arrangement of the microlenses and concave portions may be any, For example, it may be arranged in a square lattice shape or a honeycomb shape. Moreover, the microlens and the recess may be formed randomly.

In the above-described embodiments, the transmission screen is described as including a microlens substrate (lens substrate) and a Fresnel lens. However, the transmission screen of the present invention does not necessarily include a Fresnel lens. May be. For example, the transmission screen of the present invention may be substantially constituted only by the lens substrate of the present invention.
In the above-described embodiment, the configuration including the microlens as the lens portion having a more desirable shape has been described from the viewpoint of the viewing angle. However, the lens portion (lens) configuring the lens substrate is not limited thereto. For example, a lenticular lens may be used. By using a lenticular lens, the manufacturing process of the lens portion can be simplified, and the productivity of the transmission screen can be improved.

  In the embodiment described above, the lens substrate (microlens substrate) has been described as having a sheet-like (layered) diffusion portion (diffusion layer) on the light emission side of the plate-like member (substrate body). For example, the diffusing unit may be selectively provided only in the vicinity of a portion corresponding to the condensing unit of the lens unit (microlens). Thereby, it is possible to make the light use efficiency particularly excellent while sufficiently improving the viewing angle characteristics.

In the above-described embodiments, the lens substrate (microlens substrate) has been described as having a diffusing portion, but the lens substrate of the present invention does not necessarily have a diffusing portion.
In the above-described embodiments, the lens substrate is described as a member constituting a transmissive screen and a rear projector. However, the lens substrate of the present invention is applied to a transmissive screen and a rear projector. The present invention is not limited to this, and may be used for any purpose. For example, the lens-equipped substrate of the present invention may be applied to a constituent member of a liquid crystal light valve of a projection display device (front projector).

[Production of lens substrate and transmissive screen]
Example 1
The member with a recessed part provided with the recessed part for microlens formation was manufactured as follows.
<A1> First, a soda glass substrate (absolute refractive index n ₂ : 1.50) having a width of 1.2 m × length of 0.7 m 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.
Thereby, initial holes having a predetermined length were formed in a staggered pattern over the entire range of the mask forming film. The average width of the initial holes was 2 μm, and the average length was 2 μm.

<A2> Next, wet etching was performed on the soda glass substrate to form recesses (recesses for forming a microlens) having a flat shape (substantially elliptical shape) when viewed in plan on the soda glass substrate. The formed many recesses had substantially the same shape as each other. The length (pitch) in the minor axis direction of the formed recess was 54 μm, the length in the major axis direction was 82 μm, the radius of curvature was 41 μm, and the depth was 41 μm. Moreover, the occupation rate of the recessed part in the effective area | region in which the recessed part was formed was 100%.
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.

<A3> 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. When the obtained member with a recess was viewed in plan, the ratio of the area occupied by the recess in the effective region where the recess was formed was 100%.

<B1> Next, an unpolymerized (uncured) acrylic resin (an ultraviolet curable resin using a methacrylate monomer as a main raw material) is formed on the surface of the member with a recess where the recess is formed. The composition was applied, and a base film (thickness: 50 μm) composed of polyethylene terephthalate (PET) was placed thereon.
Next, the said composition was pressed through the base film with the flat plate comprised with soda glass (pressing process). At this time, air was prevented from entering between the base film and the composition.

<B2> Thereafter, the composition was completely cured by irradiating the composition with ultraviolet rays while being pressed with a flat plate to obtain a substrate body (solidification step). 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 36 μm, and a height of 36 μm. Further, the occupation ratio of the microlens in the effective region where the microlens is formed was 100%. Further, the refractive index (absolute refractive index n ₁ ) of the material constituting the formed cured portion was 1.557. Moreover, the glass transition point Tg of the resin material which comprises a board | substrate body was 90 degreeC.

<B3> Next, the flat plate was removed (pressing member removing step).
<B4> Next, a negative photosensitive material (photosensitive polyimide (produced by Asahi Kasei Co., Ltd., Pimel)) is applied to the surface of the substrate body on the output side with a roll coater, and a photosensitive film (negative photosensitive film) Was formed (photosensitive film forming step).
<B5> Next, the member with concave portions was removed from the substrate body (member removal step with concave portions).

<B6> Next, the substrate body covered with the photosensitive film was irradiated with light for exposure (photosensitive) from the side from which the member with concave portions was removed (photosensitive process). Thereby, the irradiated light was condensed by the microlens. And the photosensitive film | membrane provided in the site | part corresponding to a condensing part hardened | cured, and the photosensitive film | membrane provided in the other site | part did not harden | cure.
<B7> Next, an uncured portion of the photosensitive film was removed using a developer. Thereby, the mask which coat | covers the site | part corresponding to the condensing part of a micro lens was obtained on the surface by the side of the board | substrate body (development process).

  <B8> Thereafter, a coloring liquid was applied to the substrate body covered with the mask by dip dyeing (coloring liquid application process). At this time, the entire surface side covered with the mask was in contact with the coloring liquid, and the coloring liquid was not in contact with the surface side on which the microlens was provided (the side with the concave member). Moreover, the temperature of the substrate body and the coloring liquid when applying the coloring liquid was adjusted to 75 ° C. Disperse dye (Blue (manufactured by Futaba Sangyo)): 2 parts by weight, disperse dye (Red (manufactured by Futaba Sangyo)): 0.1 part by weight, disperse dye (Yellow (manufactured by Futaba Sangyo)): 0. A mixture prepared by dissolving 05 parts by weight, benzyl alcohol: 50 parts by weight, and surfactant: 2 parts by weight in pure water: 1000 parts by weight was used.

Under the conditions described above, the substrate main body and the coloring liquid were brought into contact with each other for 30 minutes, and then the substrate main body was taken out of the tank in which the coloring liquid was stored, sufficiently washed with water, and then dried.
Thereafter, by performing pure water cleaning and drying using N ₂ gas (removing pure water), a light-shielding portion (colored) is selectively formed near the surface of the portion not covered with the mask on the exit surface side of the substrate body. Part) was obtained. The formed light shielding portion had a thickness of 32 μm.

<B9> Next, the mask was removed from the substrate body on which the light-shielding portion was formed (mask removal process).
<B10> Next, a microlens substrate as shown in FIGS. 1 and 2 was obtained by forming a diffusion portion on the side of the substrate body where the light shielding portion was provided (diffusion portion forming step). The diffusion portion was formed by bonding a sheet material in which silica having an average particle diameter of 7 μm was dispersed in an acrylic resin to the surface side of the substrate body where the light shielding portion was provided.
A transmissive screen as shown in FIG. 3 was obtained by assembling the microlens substrate manufactured as described above and the Fresnel lens portion.

(Examples 2 and 3)
By changing the manufacturing conditions of the member with recesses, the size, shape, occupancy, etc. of the recesses of the member with recesses are changed, and the processing temperature and processing time in the coloring liquid application step for forming the light shielding part, in the coloring liquid A microlens substrate and a transmissive screen were produced in the same manner as in Example 1 except that the content of benzyl alcohol in was changed as shown in Table 1. In addition, change of the content rate of benzyl alcohol in the coloring liquid is performed by increasing or decreasing the usage amount of pure water together with the usage amount thereof, and the content rate of other components (coloring agent, surfactant) To be constant.

Example 4
First, the member with a recessed part manufactured in the said Example 1 was prepared.
<B1 ′> The same treatment as <b1> in Example 1 was performed.
<B2 ′> The same process as <b2> in Example 1 was performed.
<B3 ′> The same treatment as <b3> in Example 1 was performed.

<B4 ′> Next, a positive photosensitive material (photosensitive polyimide (manufactured by Hitachi Chemical DuPont, HD-8000)) is applied to the surface of the substrate body on the emission side by a roll coater, and a photosensitive film (positive Type photosensitive film) was formed (photosensitive film forming step).
<B5 ′> Next, the member with concave portions was removed from the substrate body (member removal step with concave portions).

<B6 ′> Next, the substrate body covered with the photosensitive film was irradiated with light for exposure (photosensitive) from the side from which the member with concave portions was removed (photosensitive process). Thereby, the irradiated light was condensed by the microlens. And the photosensitive film | membrane provided in site | parts other than the site | part corresponding to a condensing part hardened | cured, and the photosensitive film | membrane provided in the site | part corresponding to a condensing part did not harden | cure.
<B7 ′> Next, an uncured portion of the photosensitive film was removed using a developer. Thereby, the mask which coat | covers site | parts other than the site | part corresponding to the condensing part of a micro lens was obtained on the surface by the side of the board | substrate body (development process).

<B8 ′> Next, an anti-dyeing agent (anti-dyeing paste) was applied to the side of the substrate body covered with the mask (anti-dyeing agent application step).
<B9 ′> Next, the mask was removed (mask removal step). As a result, the portion of the substrate body that was covered with the mask was exposed, and the other portions were covered with the anti-dyeing agent.

<B10 ′> Thereafter, a coloring liquid was applied to the substrate body coated with the anti-dyeing agent by dip dyeing (coloring liquid application process). At this time, the entire surface side coated with the anti-dyeing agent was in contact with the coloring liquid, and the coloring liquid was not in contact with the surface side on which the microlens was provided (the side with the concave member). Moreover, the temperature of the substrate body and the coloring liquid when applying the coloring liquid was adjusted to 75 ° C. Disperse dye (Blue (manufactured by Futaba Sangyo)): 2 parts by weight, disperse dye (Red (manufactured by Futaba Sangyo)): 0.1 part by weight, disperse dye (Yellow (manufactured by Futaba Sangyo)): 0. A mixture prepared by dissolving 05 parts by weight, benzyl alcohol: 50 parts by weight, and surfactant: 2 parts by weight in pure water: 1000 parts by weight was used.
Under the conditions described above, the substrate main body and the coloring liquid were brought into contact with each other for 30 minutes, and then the substrate main body was taken out of the tank in which the coloring liquid was stored, sufficiently washed with water, and then dried.
Thereafter, by performing pure water cleaning and drying (removing pure water) using N ₂ gas, a light-shielding portion is selectively provided near the surface of the portion of the substrate body that is not covered with the dyeing-preventing agent on the emission surface side. A substrate main body on which (colored portion) was formed was obtained. The formed light shielding portion had a thickness of 32 μm.

<B11 ′> Next, the dyeing inhibitor was removed (dyeing agent removal step). The anti-dyeing agent was removed by washing with warm water containing a small amount of surfactant.
<B12 ′> Next, a microlens substrate as shown in FIGS. 1 and 2 was obtained by forming a diffusion portion on the surface side of the substrate body where the light shielding portion was provided (diffusion portion forming step). The diffusion portion was formed by bonding a sheet material in which silica having an average particle diameter of 7 μm was dispersed in an acrylic resin to the surface side of the substrate body where the light shielding portion was provided.
Thereafter, in the same manner as in Example 1, a microlens substrate and a Fresnel lens part were assembled to obtain a transmission screen as shown in FIG.

(Examples 5 and 6)
By changing the manufacturing conditions of the member with recesses, the size, shape, occupancy, etc. of the recesses of the member with recesses are changed, and the processing temperature and processing time in the coloring liquid application step for forming the light shielding part, in the coloring liquid A microlens substrate and a transmissive screen were produced in the same manner as in Example 4 except that the content of benzyl alcohol in was changed as shown in Table 1. In addition, change of the content rate of benzyl alcohol in the coloring liquid is performed by increasing or decreasing the usage amount of pure water together with the usage amount thereof, and the content rate of other components (coloring agent, surfactant) To be constant.

(Example 7)
First, the member with a recessed part manufactured in the said Example 1 was prepared.
<B1 ″> The same process as <b1> in Example 1 was performed.
<B2 ″> The same process as <b2> in Example 1 was performed.
<B3 ″> The same process as <b3> in Example 1 was performed.
<B4 ″> The same processing as in <b4> of Example 1 was performed.

<B5 ″> The same processing as in <b5> of Example 1 was performed.
<B6 ″> The same process as <b6> in Example 1 was performed.
<B7 ″> The same process as <b7> in Example 1 was performed.
<B8 ''><b7> in Example 1 except that the treatment temperature and treatment time in the coloring liquid application step for forming the light-shielding portion and the content of benzyl alcohol in the coloring liquid were changed as shown in Table 1. The same process was performed.

  <B9 ″> After that, a coloring liquid was applied to the substrate body covered with the mask by dip dyeing (coloring liquid applying process). At this time, the entire surface side provided with the microlens was in contact with the coloring liquid, and the coloring liquid was prevented from contacting the opposite surface side (the surface side where the mask was provided). Further, the temperature of the substrate body and the coloring liquid when applying the coloring liquid was adjusted to 70 ° C. Disperse dye (Blue (manufactured by Futaba Sangyo)): 2 parts by weight, disperse dye (Red (manufactured by Futaba Sangyo)): 0.1 part by weight, disperse dye (Yellow (manufactured by Futaba Sangyo)): 0. A mixture obtained by dissolving 05 parts by weight, benzyl alcohol: 10 parts by weight, and surfactant: 2 parts by weight in pure water: 1000 parts by weight was used.

Under the conditions described above, the substrate main body and the coloring liquid were brought into contact for 18 minutes, and then the substrate main body was taken out of the tank in which the coloring liquid was stored, sufficiently washed with water, and then dried.
Thereafter, by performing pure water cleaning and drying (removing pure water) using N ₂ gas, a colored portion (second colored portion) is formed on the entire surface of the substrate body near the surface on which the microlenses are provided. ) Was obtained. Moreover, the coloring density of the formed colored part (second colored part) was lower than the colored density of the light shielding part (first colored part). Further, the density of the formed colored portion (second colored portion) was 72% in terms of Y value (D65 / 2 ° field of view).

<B10 ″> Next, the mask was removed from the substrate body on which the light-shielding portion (first colored portion) and the colored portion (second colored portion) were formed (mask removing step).
<B11 ″> Next, a microlens substrate as shown in FIGS. 1 and 2 was obtained by forming a diffusion portion on the side of the substrate body where the light shielding portion was provided (diffusion portion forming step). . The diffusion portion was formed by bonding a sheet material in which silica having an average particle diameter of 7 μm was dispersed in an acrylic resin to the surface side of the substrate body where the light shielding portion was provided.
Thereafter, in the same manner as in Example 1, a microlens substrate and a Fresnel lens part were assembled to obtain a transmission screen as shown in FIG.

(Examples 8 and 9)
In the colored liquid application process (first colored liquid application process) for changing the size, shape, occupancy, etc. of the concave part of the member with the concave part by changing the manufacturing conditions of the member with the concave part, and forming the light shielding part A microlens substrate and a transmissive screen were produced in the same manner as in Example 7 except that the treatment temperature and treatment time and the content of benzyl alcohol in the colored liquid were changed as shown in Table 1. In addition, change of the content rate of benzyl alcohol in the coloring liquid is performed by increasing or decreasing the usage amount of pure water together with the usage amount thereof, and the content rate of other components (coloring agent, surfactant) To be constant.

(Example 10)
First, the member with a recessed part manufactured in the said Example 1 was prepared.
<B1 ′ ″> The same process as <b1 ′> in Example 4 was performed.
<B2 ′ ″> The same process as <b2 ′> in Example 4 was performed.
<B3 ′ ″> The same process as <b3 ′> in Example 4 was performed.

<B4 ′ ″> The same process as <b4 ′> in Example 4 was performed.
<B5 ′ ″> The same process as <b5 ′> in Example 4 was performed.
<B6 ′ ″> The same process as <b6 ′> in Example 4 was performed.
<B7 ′ ″> The same process as <b7 ′> in Example 4 was performed.
<B8 ′ ″> The same process as <b8 ′> in Example 4 was performed.

<B9 ′ ″> The same process as <b9 ′> in Example 4 was performed.
<B10 ′ ″><b10 of Example 4 except that the treatment temperature and treatment time in the coloring liquid application step for forming the light-shielding portion and the content of benzyl alcohol in the coloring liquid were changed as shown in Table 1. The same processing as'> was performed.
<B11 ′ ″> After that, a coloring liquid was applied to the substrate body coated with the anti-dyeing agent by dip dyeing (coloring liquid application process). At this time, the whole surface side provided with the microlens was in contact with the coloring liquid, and the coloring liquid was not in contact with the opposite surface side (the surface side to which the anti-staining agent was applied). Further, the temperature of the substrate body and the coloring liquid when applying the coloring liquid was adjusted to 70 ° C. Disperse dye (Blue (manufactured by Futaba Sangyo)): 2 parts by weight, disperse dye (Red (manufactured by Futaba Sangyo)): 0.1 part by weight, disperse dye (Yellow (manufactured by Futaba Sangyo)): 0. A mixture prepared by dissolving 05 parts by weight, benzyl alcohol: 20 parts by weight, and surfactant: 2 parts by weight in pure water: 1000 parts by weight was used.

Under the conditions as described above, the substrate main body and the coloring liquid were brought into contact for 12 minutes, and then the substrate main body was taken out of the tank in which the coloring liquid was stored, sufficiently washed with water, and then dried.
Thereafter, by performing pure water cleaning and drying (removing pure water) using N ₂ gas, a colored portion (second colored portion) is formed on the entire surface of the substrate body near the surface on which the microlenses are provided. ) Was obtained. The coloring density of the formed colored part (second colored part) was lower than that of the light-shielding part (first colored part). The density of the formed colored portion (second colored portion) was 76% in terms of Y value (D65 / 2 ° field of view).

<B12 ′ ″> Next, the dyeing inhibitor was removed (dyeing agent removal step). The anti-dyeing agent was removed by washing with warm water containing a small amount of surfactant.
<B13 '''> Next, a microlens substrate as shown in FIGS. 1 and 2 was obtained by forming a diffusing portion on the surface side of the substrate body where the light shielding portion was provided (diffusing portion forming step). ). The diffusion portion was formed by bonding a sheet material in which silica having an average particle diameter of 7 μm was dispersed in an acrylic resin to the surface side of the substrate body where the light shielding portion was provided.
Thereafter, in the same manner as in Example 1, a microlens substrate and a Fresnel lens part were assembled to obtain a transmission screen as shown in FIG.

(Examples 11 and 12)
In the colored liquid application process (first colored liquid application process) for changing the size, shape, occupancy, etc. of the concave part of the member with the concave part by changing the manufacturing conditions of the member with the concave part, and forming the light shielding part A microlens substrate and a transmissive screen were produced in the same manner as in Example 10 except that the treatment temperature, treatment time, and the content of benzyl alcohol in the colored liquid were changed as shown in Table 1. In addition, change of the content rate of benzyl alcohol in the coloring liquid is performed by increasing or decreasing the usage amount of pure water together with the usage amount thereof, and the content rate of other components (coloring agent, surfactant) To be constant.

(Comparative Example 1)
A microlens substrate and a transmissive screen were manufactured in the same manner as in Example 1 except that the light shielding portion was not formed on the substrate body. That is, a microlens substrate and a transmissive screen were manufactured in the same manner as in Example 1 except that the steps <b4>, <b6>, <b7>, <b8>, and <b9> were omitted.

(Comparative Example 2)
As described below, a microlens substrate and a transmissive screen were manufactured in the same manner as in Example 1 except that a light shielding portion was formed outside the substrate body.
First, a substrate body was manufactured in the same manner as in Example 1.
Then, the flat plate and the member with a recess were removed from the manufactured substrate body.

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

Thereafter, development was performed for 40 seconds using a 0.5 wt% aqueous KOH solution.
Thereafter, pure water washing and drying using N ₂ gas (removing pure water) were performed, and further post-baking treatment was performed by IR. Thereby, a black matrix having openings corresponding to the respective microlenses was formed. The thickness of the formed black matrix was 5.0 μm.

(Comparative Example 3)
A lens substrate (lenticular lens sheet) having a light-shielding portion (light-shielding layer) was produced by a method as disclosed in JP-A-2002-350981. Hereinafter, this method will be described.
Using an apparatus as shown in FIG. 22, a polyethylene terephthalate resin film having a thickness of 75 μm is used as the substrate H6, and an ultraviolet curable resin composition H7a is supplied from the dispenser H33, and the pitch is 130 μm on one surface of the substrate H6. A lenticular lens sheet H2 was manufactured in which a lenticular lens layer H7 in which lenticular lenses having a height of about 45 μm were closely arranged was laminated.

  On the side of the lenticular lens sheet H2 where the lenticular lens layer H7 is not laminated, a positive resist dry film (P-RZ30, manufactured by Tokyo Ohka Kogyo Co., Ltd.) having a thickness of 5 μm was laminated with a roller. Then, it exposed with the ultraviolet-ray from the lenticular lens layer H7 side with the ultraviolet irradiation device H34. After exposure, the exposed area is dissolved and removed by immersing in a 1% aqueous solution of sodium carbonate for 1 minute, then washed with water and dried to remove the dry film on the condensing area of each lenticular lens layer H7. As a result, an intermediate was obtained in which the dry film of the non-light-collecting part became a convex part.

  As a thermal transfer sheet, an ink layer containing a silicone-treated layer on the back of a polyethylene terephthalate resin film having a thickness of 4.5 μm, a wax layer (peeling layer) having a thickness of 0.3 μm on the front, and 50% of carbon black having a thickness of 0.5 μm. , And a polyester resin layer (heat-sensitive adhesive layer) having a thickness of 0.5 μm sequentially laminated, and transferred onto the convex portions of the intermediate dry film at a transfer temperature of 90 ° C. Thus, a lenticular lens sheet having a light shielding layer (light shielding part) was obtained.

  Table 1 summarizes the configuration of the substrate body, the conditions of the coloring liquid used for forming the light shielding part, the processing conditions of the coloring liquid application process (first coloring liquid application process) for forming the light shielding part, etc. Show. In Table 1, the glass transition point of the resin material constituting the substrate body is indicated by Tg [° C.], and the processing temperature in the color liquid application step (first color liquid application step) for forming the light shielding portion is T [° C.]. The color liquid application process (contact) time in the color liquid application process (first color liquid application process) for forming the light shielding part is indicated by t [min].

[Evaluation of transmittance]
The transmittance was evaluated for the transmissive screens of the examples and comparative examples.
The transmittance is evaluated using a spectrophotometer (Otsuka Electronics Co., Ltd., instantaneous multi-photometry system “MCPD-1000 (28C)”), and from the light source of the spectrophotometer (spectral spectrum measurement region 380 nm to 800 nm). In parallel with the normal direction, the Y value of the total light transmittance (D65 / 2 ° field of view) received by the integrating sphere placed on the opposite surface of the light irradiated from the light incident side of the microlens substrate (substrate body) ) As the transmittance.

[Production of rear projector]
A rear projector as shown in FIG. 20 was manufactured using the transmissive screens of the respective Examples and Comparative Examples.
[Evaluation of contrast]
Contrast evaluation was performed on the transmissive screens produced in each of the above examples. Contrast is the amount of increase in the front luminance of white display (white luminance) LW (cd / m ² ) when 410 lx all white light is incident in the dark room and the front luminance of black display when the light source is completely turned off in the bright room. (Black luminance increase amount) A ratio with LB (cd / m ² ), LW / LB, was obtained. The bright room was measured in a room with an outside light illuminance of 185 lx (bright room). A luminance meter BM-7 manufactured by Topcon was used for the luminance measurement.

The results were evaluated according to the following four-stage criteria.
A: LW / LB is 250 or more.
A: LW / LB is 200 or more and less than 250.
Δ: LW / LB is 100 or more and less than 200.
X: LW / LB is less than 100.

[Evaluation of brightness (brightness)]
With respect to the transmissive screens of the respective Examples and Comparative Examples, the luminance (brightness) of the displayed images was evaluated. As the evaluation value, LW (cd / m ² ) was divided by the illuminance 410 of incident light and multiplied by π (3.14), and the brightness per unit area was compared.
The results were evaluated according to the following four-stage criteria.
A: Brightness per unit area is 2.5 or more.
○: Brightness per unit area is 2.0 or more and less than 2.5.
Δ: Brightness per unit area is 1.0 or more and less than 2.0.
X: The brightness per unit area is less than 1.0.

[Evaluation of black level]
The difference between the front luminance increase (black luminance increase) LB (cd / m ² ) when the light source is completely turned off in the bright room and the black display luminance when the light source is completely turned off in the dark room is the blackness. Rated as a level. A smaller number indicates that the black level can be maintained without the influence of outside light.
The results were evaluated according to the following three criteria.
A: Less than 1
○: 1 or more and less than 1.5.
X: 1.5 or more.

[Evaluation of viewing angle level]
With the sample images displayed on the transmissive screens of the rear projectors of the respective examples and comparative examples, the observer approaches the screen from the state of facing the screen, and is visually observed from the vertical direction (vertical direction). The angle at which extreme brightness reduction (discontinuous brightness reduction) was observed was compared according to the following criteria.
The results were evaluated according to the following four-stage criteria. The angle refers to an angle formed between the normal direction and the observer's line-of-sight direction from the center of the screen.
A: There is no discontinuous decrease in brightness up to 80 ° or more. ○: There is a discontinuous decrease in brightness near 80 °. Δ: There is a discontinuous decrease in brightness near 70 °. There is a discontinuous decrease in brightness around 60 °

[Evaluation of diffracted light, moire and color unevenness]
Sample images were displayed on the transmissive screens of the rear projectors of the examples and comparative examples. The displayed images were evaluated for the occurrence of diffracted light, moire and color unevenness according to the following four criteria.
A: No diffracted light, moire, or color unevenness is observed.
○: Almost no diffracted light, moire or color unevenness is observed.
Δ: At least one of diffracted light, moire, and color unevenness is slightly observed.
X: At least one of diffracted light, moire and color unevenness is remarkably recognized.
These results are summarized in Table 2.

  As is clear from Table 2, the present invention was excellent in light utilization efficiency and viewing angle characteristics. In the present invention, a high-contrast image can be suitably displayed. Further, in the present invention, the generation of diffracted light, moire, color unevenness and the like was effectively prevented.

It is a typical longitudinal section showing a 1st embodiment of a lens substrate (micro lens substrate) of the present invention. FIG. 2 is a schematic plan view of the lens substrate shown in FIG. 1. It is a typical longitudinal cross-sectional view which shows 1st Embodiment of the transmissive screen of this invention provided with the lens board | substrate (microlens 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 method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal section showing a 2nd embodiment of a lens substrate (micro lens substrate) of the present invention. It is a typical longitudinal cross-sectional view which shows 2nd Embodiment of the transmissive screen of this invention provided with the lens board | substrate (microlens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows an example (1st method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a typical longitudinal cross-sectional view which shows another example (2nd method) of the manufacturing method of the lens board | substrate (micro lens board | substrate) shown in FIG. It is a figure which shows typically the rear type projector to which the transmission type screen of this invention is applied. It is a typical longitudinal cross-sectional view for demonstrating the conventional lens board | substrate. It is sectional drawing which shows typically the manufacturing apparatus and manufacturing method of a lens board | substrate used in the comparative example 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Micro lens board | substrate (lens board | substrate) 2 ... Board | substrate main body (plate-shaped member) 21 ... Micro lens (lens part) 211 ... Center 22 ... Light-shielding part (1st coloring part) 23 ... Composition 24 ... Transparent film 25 ... First row 26 ... Second row 27 ... Colored portion (second colored portion) 3 ... Diffusion portion (diffusion plate) 4 ... Mask forming film 5 ... Fresnel lens portion 51 ... Fresnel lens 6 ... Member with recess ( Microlens forming concave member) 61 ... concave portion 7 ... substrate 8 ... mask 81 ... initial hole 89 ... back surface protective film 91 ... photosensitive film (negative photosensitive film) 92 ... mask 95 ... photosensitive film (positive photosensitive) Membrane) 96 ... Mask 99 ... Antistaining agent 10 ... Transmission type screen 11 ... Flat plate (pressing member) 300 ... Rear projector 310 ... Projection optical unit 320 ... Light guide mirror 340 ... Housing H2 ... Lenticular Lens sheet H6 ... substrate H7 ... the lenticular lens layer H7A ... UV curable resin composition H33 ... dispenser H34 ... ultraviolet radiation device

Claims (15)

A lens substrate made of a plate-like member having a plate shape and having a large number of lens portions provided on one surface side,
A light-shielding portion having a function of preventing reflection of external light on the side opposite to the side where the lens portion is provided;
The lens substrate according to claim 1, wherein the light shielding part is provided inside the plate-like member by dyeing at least at a part other than the part corresponding to the light collecting part of the lens part.   The lens substrate according to claim 1, wherein the light shielding portion has a thickness of 0.1 to 50 μm.   The lens substrate according to claim 1, further comprising a diffusing portion having a function of diffusing light on a surface side of the plate-like member on which the light shielding portion is provided.   The lens substrate according to claim 1, wherein the light-shielding portion is made of a material containing a disperse dye.   5. The lens substrate according to claim 1, wherein the light shielding portion is formed using a coloring liquid containing a colorant and benzyl alcohol.   The lens substrate according to claim 5, wherein the coloring liquid contains at least one compound selected from a benzophenone-based compound and a benzotriazole-based compound in addition to the colorant and the benzyl alcohol.   The lens substrate according to any one of claims 1 to 6, wherein the lens substrate is a microlens substrate including a microlens as the lens portion.   The lens substrate according to any one of claims 1 to 7, wherein the lens substrate has a colored portion formed by staining near the surface of the lens portion.   The lens substrate according to claim 8, wherein a color density of the colored portion is lower than a color density of the light shielding portion. A method for manufacturing the lens substrate according to claim 1, comprising:
A photosensitive member made of a positive photosensitive material on the surface opposite to the side where the lens part is provided of the plate-like member having a plate shape and a large number of lens parts provided on one side. A photosensitive film forming step of forming a film;
A photosensitive step of exposing a part of the photosensitive film by irradiating the photosensitive film with light through the plate-like member to form a photosensitive part exposed;
A developing step for removing the photosensitive portion;
After the development step, an anti-dyeing agent applying step of applying an anti-dyeing agent for preventing dyeing to the surface side of the plate-like member provided with the photosensitive film;
A photosensitive film removing step of removing the photosensitive film remaining on the plate-like member;
A method for producing a lens substrate, comprising: a coloring liquid applying step for applying a coloring liquid on a surface side of the plate-like member to which the anti-staining agent is applied. A method for manufacturing the lens substrate according to claim 1, comprising:
A photosensitive member made of a negative photosensitive material on the opposite side of the plate-like member from which the lens portion is provided. A photosensitive film forming step of forming a film;
A photosensitive step of exposing a part of the photosensitive film by irradiating the photosensitive film with light through the plate-like member to form a photosensitive part exposed;
A developing step for removing the photosensitive portion;
A method for producing a lens substrate, comprising: a color liquid application step for applying a color liquid on a surface side of the plate-like member on which the photosensitive film is formed.   The method for manufacturing a lens substrate according to claim 11, further comprising a photosensitive film removing step of removing the photosensitive film remaining on the plate-like member after the coloring liquid applying step.   A transmissive screen comprising the lens substrate according to claim 1. A Fresnel lens part having a Fresnel lens formed on the light exit side;
A transmissive screen comprising: the lens substrate according to claim 1 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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