JP2007187869A - Transmission type screen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission type screen designed so as to remove reflection of unnecessary outdoor light and to improve contrast of a rear projection television. <P>SOLUTION: The transmission type screen is used for a rear projection television. The average value Y1 of 450-520 nm light transmittance is smaller than the average value Y2 of 400-450 nm light transmittance and the average value Y3 of 520-570 nm light transmittance. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a transmissive screen used in a rear projection type (rear type) projection television (hereinafter referred to as “RPTV”).

Conventionally, RPTVs having a CRT projector as a light source have been used. In recent years, projectors such as light valves using liquid crystal, DMD (Digital-Micromirror-Device), and LCOS (Liquid-Crystal on Silicon) have come to be used to provide higher-brightness and high-definition images. Projection television has been put into practical use.
Along with this, there is a problem that the RPTV is viewed in a brighter room, and external light such as a fluorescent lamp is reflected on the surface of the transmission screen, leading to a decrease in contrast.
Therefore, usually, a low-reflective coating made of a low-refractive material is applied to the outermost surface of the transmissive screen to suppress external light reflection (see Patent Documents 1 to 3).

Japanese Patent Laid-Open No. 05-289178 Japanese Patent Laid-Open No. 06-160982 JP 2001-117167 A

However, only such a low reflection treatment is not sufficient to suppress a decrease in contrast, and a more effective external light antireflection function is demanded at present.
The present invention has been made to solve the above-described problems, and improves the contrast of the RPTV by removing unnecessary specific external light reflection without unnecessarily reducing the emission luminance of the RPTV. The present invention provides a transmissive screen capable of satisfying the requirements.

  In order to achieve the above object, the present invention is a transmission screen used for RPTV, wherein the average value Y1 of the light transmittance of 450 to 520 nm is the average value Y2 of the light transmittance of 400 to 450 nm and 520 to 570 nm. Provided is a transmissive screen having a light transmittance smaller than the average value Y3.

The transmissive screen of the present invention preferably contains a compound whose constituent member has a maximum absorption in a wavelength region of 450 to 520 nm.
The compound having the maximum absorption in the wavelength range of 450 to 520 nm is preferably an anthraquinone dye or a perinone dye.

  In the transmission screen of the present invention, it is preferable that the difference between Y1 and Y3 is 5 to 25%, and the difference between Y1 and Y2 is 5 to 20%.

  The transmissive screen of the present invention removes unnecessary external light reflection without reducing the emission luminance of RPTV more than necessary, and improves the contrast of RPTV, and is suitable for RPTV.

The present invention will be described below with reference to the drawings.
FIG. 4 shows an RPTV emission spectrum (measured value of emission spectrum of KDF-42HD900 manufactured by Sony Corporation) using a general projector ultra-high pressure mercury lamp as a light source, and three wavelength ranges widely used for indoor lighting. The emission spectrum of the light emitting fluorescent lamp F10 is shown.
Comparing both emission spectra in detail, the emission spectrum of the three-wavelength fluorescent lamp F10 has a strong emission peak in the wavelength range of 450 to 520 nm, but the emission spectrum of RPTV has three primary colors in this wavelength range. It was found that there was no luminance peak (red, blue, green) and the emission was relatively weak. In contrast, F10 has emission spectra in other wavelength ranges, but the peak wavelengths of these wavelength spectra almost overlap with the luminance peaks of the three primary colors (red, blue, and green) of RPTV. I found out. Specifically, a blue luminance peak exists in the wavelength region of 400 to 450 nm where the peak wavelength of the emission spectrum of F10 exists. On the other hand, a green luminance peak exists in the wavelength range of 520 to 570 nm where the peak wavelength of the emission spectrum of F10 exists.
Accordingly, if light in the wavelength region of 450 to 520 nm can be selectively absorbed in the transmissive screen, the external light is weakened in the process of reciprocating the transmissive screen, and as a result, the emission luminance of the RPTV is greatly reduced. In addition, the present inventors have found that the reflection of external light on the surface of the transmissive screen can be effectively reduced and the contrast can be improved.

The transmission type screen of the present invention is characterized in that the average value Y1 of the light transmittance of 450 to 520 nm is smaller than the average value Y2 of the light transmittance of 400 to 450 nm and the average value Y3 of the light transmittance of 520 to 570 nm. To do. Here, the light transmittance is a total light transmittance in a specific wavelength range, and was measured in accordance with JIS-K7105 (1981) measuring method B in Examples described later.
Therefore, in the transmissive screen of the present invention, the relationship between Y1, Y2, and Y3 satisfies the following formula (1).
Y1 <Y2 and Y1 <Y3 (1)

  If the above formula (1) is satisfied, light in the wavelength region of 450 to 520 nm is selectively absorbed when passing through the transmission screen. As a result, external light is weakened in the process of reciprocating the transmissive screen. As a result, the reflection of external light on the surface of the transmission screen can be effectively reduced and the contrast can be improved without significantly reducing the emission luminance of the RPTV.

In the transmission type screen of the present invention, it is preferable that the relationship between Y1 and Y2 and Y3 satisfies the above formula (1) and the following is satisfied from the viewpoint of further improving the contrast.
Y2 is preferably 60 to 90%. Y1 is preferably 55 to 85%. Y3 is preferably 65 to 98%.
Further, in terms of further improvement in contrast, the difference between Y1 and Y3 is preferably 5 to 25%, the difference between Y1 and Y2 is preferably 5 to 20%, and the difference between Y1 and Y3 is More preferably, it is 5 to 25%, and the difference between Y1 and Y2 is 5 to 20%.

  In the transmissive screen of the present invention, in order for the relationship between Y1, Y2, and Y3 to satisfy the above formula (1), light in the wavelength region of 450 to 520 nm is selected from the light rays that pass through the transmissive screen. As long as it can be absorbed. In order to achieve this, a compound having a maximum absorption in the wavelength region of 450 to 520 nm may be contained in a transmissive screen component (such as a lenticular lens sheet or a light diffusing plate as described later).

Specific examples of the compound having the maximum absorption in the wavelength range of 450 to 520 nm include anthraquinone dyes such as solvent orange and solvent red, and perinone dyes. Specifically, Red A-2G (CI Solvent Red 179, manufactured by Nippon Kayaku Co., Ltd., perinone dye, maximum absorption wavelength 480 nm), Red AG (CI Solvent Red 135, Japan) Manufactured by Kayaku Co., Ltd., perinone dye, maximum absorption wavelength 512 nm), Red G (manufactured by Nippon Kayaku Co., Ltd., anthraquinone dye, maximum absorption wavelength 502 nm), Orange SF-R (manufactured by Nippon Kayaku Co., Ltd., The maximum absorption wavelength is 510 nm).
Hereinafter, in the present specification, a compound having the maximum absorption in the wavelength region of 450 to 520 nm contained in the constituent member of the transmission screen may be referred to as “light absorbing compound”.

  5 and 6 are graphs showing the relationship between the emission spectrum of RPTV and the emission spectrum of F10 and the absorption curve of the compound having the maximum absorption in the wavelength region of 450 to 520 nm. FIG. 5 shows an absorption curve of Red A-2G (CI Solvent Red 179, manufactured by Nippon Kayaku Co., Ltd., perinone dye, maximum absorption wavelength 480 nm) used in Examples 1 to 3. FIG. 6 shows an absorption curve of Orange SF-R (manufactured by Nippon Kayaku Co., Ltd., maximum absorption wavelength 510 nm).

In the present invention, the light-absorbing compound has maximum absorption in the wavelength region of 450 to 520 nm, in addition to the degree of light absorption in the wavelength region of 450 to 520 nm and the degree of light absorption in other wavelength regions, particularly 400. It is preferable that there is a large difference between the degree of light absorption in the wavelength region of ˜450 nm and the wavelength region of 520 to 570 nm. For this reason, it is preferable that the light absorption compound has a molar extinction coefficient ratio represented by the following formula of 1.5 or more for any wavelength region described in the denominator.
Molar extinction coefficient ratio = (average value of molar extinction coefficient in the wavelength range of 450 to 520 nm) / (average value of molar extinction coefficient in the wavelength range of 400 to 450 nm or 520 to 570 nm)
In addition, Red A-2G used in Examples 1 to 3 has a molar extinction coefficient ratio with respect to a molar extinction coefficient in a wavelength range of 400 to 450 nm and a molar extinction coefficient ratio with respect to a molar extinction coefficient in a wavelength range of 520 to 570 nm. 2.0.

As shown in FIG. 5 and FIG. 6, even if it is a light absorption compound, the shape of the absorption curve is various, and there are a thing with a sharp absorption curve and a broad thing. In the present invention, the light absorbing compound preferably has a sharp absorption curve so as not to lower the RPTV emission luminance more than necessary. For this reason, in addition to having a maximum absorption in the wavelength region of 450 to 520 nm, the light absorption compound has a boundary molar extinction coefficient ratio represented by the following formula for any wavelength described in the denominator in the formula. Is preferably 1.1 or more, and more preferably 1.2 or more.
Boundary molar extinction coefficient ratio = (molar extinction coefficient at maximum absorption) / (molar extinction coefficient at 450 nm or 520 nm)
In addition, Red A-2G used in Examples 1 to 3 has a boundary molar extinction coefficient ratio of 1.18 (ratio to molar extinction coefficient at 450 nm) and 1.21 (ratio to molar extinction coefficient at 520 nm). .

In FIG. 7, the emission spectrum of the RPTV after passing through the transmission screen having a member containing Red A-2G is indicated by a broken line B, and the three-wavelength region fluorescent lamp F10 after passing through the transmission screen is shown. Is shown by a broken line D. In FIG. 7, the emission spectrum of the RPTV before passing through the transmission screen is indicated by a solid line A, and the emission spectrum of the three-wavelength region fluorescent lamp F10 before passing through the transmission screen is indicated by a solid line C. Has been. In FIG. 7, spectra A and C indicated by solid lines are the same as the emission spectrum of RPTV and the emission spectrum of F10 shown in FIG. 4, respectively.
As is clear from FIG. 7, when the transmission type screen having a member including Red A-2G is transmitted, compared to the emission spectrum of RPTV (solid line A (before transmission) −broken line B (after transmission)), It can be seen that the emission spectrum (solid line C (before transmission) -broken line D (after transmission)) in the specific wavelength range of the three-wavelength fluorescent lamp F10 is greatly reduced. As a result, it is possible to solve the problem that the contrast is lowered by reflecting the external light from the fluorescent lamp on the transmission screen without lowering the emission luminance of the RPTV more than necessary.
FIG. 7 is a spectrum of a transmission screen having a member containing Red A-2G whose spectrum is shown in FIG. 5, but is a light-absorbing compound such as Orange SF-R shown in FIG. Similarly, it can solve the problem that leads to a decrease in contrast.

In the present invention, the light absorbing compound may be contained in any part as long as it is a constituent member of a transmission screen that can serve as an optical path for external light.
FIG. 1 is a schematic cross-sectional view showing an embodiment of a transmission screen according to the present invention, and shows a general configuration of a transmission screen used in an RPTV. In FIG. 1, the transmissive screen 10 is shown with a light source (not shown) on the right side in the figure. The arrows in FIG. 1 indicate the traveling direction of light from the light source.
In the transmission screen 10 shown in FIG. 1, the Fresnel lens sheet 11, the lenticular lens sheet 12, and the light diffusion plate 14 are arranged in this order from the light source side, and between the lenticular lens sheet 12 and the light diffusion plate 14. Is provided with an adhesive layer 13 containing an adhesive substance, and a striped light shielding layer (black stripe) 15 is provided on the flat surface of the lenticular lens sheet 12. Here, the Fresnel lens sheet 11 and the lenticular lens sheet 12 are fixed by overlapping each other and pasting them together with a double-sided tape. The lenticular lens sheet 12 and the light diffusing plate 14 are joined via an adhesive layer 13.

  The Fresnel lens sheet 11 mainly uses light from the light source as parallel rays. A Fresnel lens sheet 11 shown in FIG. 1 is composed of a plurality of concentric lenses having a mountain-like cross section. However, the shape of the Fresnel lens sheet in the transmission screen of the present invention is not limited to this, and various shapes known in this technical field can be used.

  The lenticular lens sheet 12 mainly expands light from the light source in the horizontal direction. The lenticular lens sheet 12 shown in FIG. 1 has an array shape in which a plurality of cylindrical lenses are regularly arranged at a constant period. However, the lenticular lens sheet in the transmissive screen of the present invention is not limited to this, and has various shapes known in this technical field as long as it is configured to expand light from the light source in the horizontal direction. Can be used.

  The Fresnel lens sheet 11 and the lenticular lens sheet 12 are produced using a transparent substrate. Specific examples of the transparent substrate include a glass substrate and a transparent resin substrate. Examples of the resin constituting the transparent resin substrate include acrylic resin, polycarbonate resin, acrylic-styrene copolymer resin, polyester resin, polyethylene resin, polyolefin resin, and urethane resin.

The light diffusing plate 14 is made of a transparent resin base material, and a light diffusing agent is dispersed in the transparent resin base material. Alternatively, the light diffusion plate 14 may be a glass substrate instead of a transparent resin substrate, and a layer in which a light diffusing agent is dispersed may be provided on the substrate surface as described later.
As a resin material which comprises a transparent resin base material, what was illustrated as a resin material which comprises the transparent resin base material of the lenticular lens sheet 11 and the Fresnel lens sheet 12 can be used.

  The light diffusing agent is transparent, that is, fine particles that hardly absorb in the visible light region, and the fine particle diameter is about several μm. The material of the light diffusing agent is not particularly limited, and inorganic fine particles and organic fine particles can be used. Either can be used.

  Specific examples of inorganic fine particles include, for example, titanium oxide, zinc oxide, zirconium oxide, niobium oxide, tantalum oxide, tin oxide, indium oxide, silicon dioxide (silica), inorganic oxide fine particles such as aluminum oxide, calcium carbonate And inorganic fine particles such as glass beads. Among these, fine particles of titanium oxide, silica, and aluminum oxide are preferable from the viewpoint of low cost and excellent durability.

  Examples of the organic fine particles include polymer beads. Examples of polymer beads include those made of acrylic, styrene, and silicone resins. Particularly, cross-linked resins such as acrylic (PMMA) resin fine particles and MS (acryl-styrene copolymer) resin fine particles are chemical resistant. preferable. Further, the shape of the polymer beads is preferably a true sphere in that it can be uniformly dispersed in the coating film.

  The average particle size of the light diffusing agent is preferably 0.1 to 50 μm. Within this range, it is convenient to obtain an appropriate diffusion performance and is advantageous in that it can be easily dispersed uniformly. In terms of superiority in this characteristic, 0.2 to 30 μm is more preferable, and 0.5 to 15 μm is particularly preferable.

  As for the geometric board thickness of the transparent resin base material which comprises the light diffusing plate 14, 1-6 mm is preferable. Within this range, a transmission screen with sufficient visible light transmittance and sufficient strength can be obtained. In order to be excellent in this characteristic, the geometrical plate thickness of the transparent resin substrate is more preferably 1.5 to 4 mm, and particularly preferably 1.5 to 2.5 mm.

In order to use light from the light source without loss, it is preferable that the visible light transmittance (JIS K7361-1 (1997)) of the light diffusion plate 14 is 85% or more. Moreover, in the light diffusing plate 14, it is preferable that the light diffusing agent is uniformly dispersed in the transparent resin base material.
In order to improve the contrast of the display image, the light diffusion plate 14 may be colored with a dye or a pigment.

  The stripe-shaped light shielding layer (black stripe) 15 is formed on the flat surface of the lenticular lens sheet 12, that is, on the back surface side with respect to the lens surface. More specifically, the light shielding layer (black stripe) 15 is formed on a non-condensing portion region where image light does not pass on the flat surface of the lenticular lens sheet 12. The light shielding layer (black stripe) 15 improves the contrast of the transmissive screen 10 by absorbing external light.

In the present invention, the light absorbing compound is contained in a constituent member that can serve as an optical path of external light of the transmissive screen 10. Here, the constituent member containing the light absorbing compound is not particularly limited as long as it can serve as an optical path for external light.
In addition, when it says that it is made to contain in the structural member of the transmission type screen 10, forming the layer containing a light-absorbing compound on the surface of a structural member other than making a structural member actually contain a light-absorbing compound is included. .
When the constituent member of the transmission screen 10 is made of a transparent resin base material, the transparent resin base material may contain a light absorbing compound. For example, the light-absorbing compound may be contained in the transparent resin base material constituting the light diffusion plate 14. Moreover, when the Fresnel lens sheet 11 and the lenticular lens sheet 12 are produced using a transparent resin base material, a light absorbing compound may be contained in the transparent resin base material. When the transparent resin substrate is formed by containing a light absorbing compound, a method of dissolving or dispersing the compound in the resin material and molding it into a plate shape by extrusion molding or the like can be employed.

  In the present invention, in order to selectively absorb light in the wavelength region of 450 to 520 nm, a light absorbing compound may be contained in a constituent member of a transmission screen that can be an optical path of external light, and the content thereof is particularly limited. Not. Specifically, the light absorbing compound can be contained in the constituent member of the transmission screen in an amount of 0.001 to 50% by mass, particularly 0.01 to 10% by mass. For example, in Example 1 to be described later, by including 0.01% by mass of a visible light dye (maximum absorption wavelength: 480 nm) as a light-absorbing compound in the transparent resin substrate constituting the light diffusing plate 14, 450 to 520 nm It selectively absorbs light in the wavelength range.

  When the constituent member of the transmissive screen 10 is produced using a glass substrate, a layer containing a light absorbing compound may be formed on the surface of the glass substrate. Specifically, the light absorbing compound can be contained in the layer in an amount of 0.001 to 50% by mass, particularly 0.01 to 10% by mass. For example, when the Fresnel lens sheet 11 or the lenticular lens sheet 12 is produced using a glass substrate, a layer containing a light absorbing compound may be formed on the surface of the glass substrate. In addition, even if it is a case where the structural member of the transmissive screen 10 is produced using the transparent resin base material, you may form the layer containing a light absorption compound on the surface of this transparent resin base material.

  In the case of forming a layer containing a light absorbing compound on the surface of the constituent member, a method of applying a paint comprising the light absorbing compound and a matrix component can be employed. In this case, as the matrix component, an organic matrix such as an acrylic resin, an acrylic-styrene copolymer resin, a silicone resin, or an epoxy resin, a hydrolyzate of metal alkoxide, an inorganic matrix such as low-melting glass, or a composite thereof is used. be able to. Examples of the method for applying the paint to the surface of the constituent member include known methods such as spin coating, dip coating, screen printing, and die coating.

FIG. 2 is a view showing another aspect of the transmission screen of the present invention, and the structure of the light diffusion plate 14 is different from that of FIG. In the transmissive screen 10 ′ shown in FIG. 2, the light diffusing plate 14 is composed of a glass substrate 14a and a light diffusing layer 14b formed on the glass substrate 14a. The light diffusing layer 14b is composed of a matrix constituting the light diffusing layer 14b and a light diffusing agent dispersed in the matrix.
In the light diffusing layer 14b, the matrix refers to a material that forms the light diffusing layer itself. Specifically, the matrix is formed from a matrix forming component to be described later and, in some cases, a curing agent necessary for curing the matrix forming component. Component of the layer.

Since the matrix-forming component holds the light diffusing agent, it acts as a binder for the light diffusing agent after the layer is formed. The matrix-forming component is a material having adhesiveness with the substrate after forming the layer, and is preferably transparent. The matrix-forming component is preferably a material that enables formation of a layer by coating, and in particular, a crosslinked coating material that is cured by heat, ultraviolet rays, or the like. Specific examples of such matrix-forming components include urethane resins, acrylic resins, styrene resins, polycarbonate resins, polymethylpentene resins, acrylic-styrene copolymer resins, epoxy resins, olefin resins, Examples thereof include resin materials such as silicone resins, cross-linked products obtained from hydrolysates of metal alkoxides, inorganic materials such as low-melting glass, and mixtures thereof.
As the light diffusing agent dispersed in the matrix, those exemplified as the light diffusing agent contained in the transparent resin substrate can be used.

  The light diffusion layer 14b may have a single-layer configuration or a two-layer configuration, but a two-layer configuration is preferable in that the degree of freedom in design such as diffusivity is increased. When the light diffusion layer 14b has a two-layer structure, the materials of the first light diffusion agent and the second light diffusion agent included in the first light diffusion layer and the second light diffusion layer may be the same or different. . Each of the light diffusing agents contained in the light diffusing layer 14b has a refractive index difference Δn with the matrix forming component of 0.005 ≦ Δn ≦ 0.2, preferably 0.005 ≦ Δn ≦ 0.1. . The refractive index difference in this specification means an absolute value of a difference between two kinds of refractive indexes. The refractive index of the matrix forming component may be lower or higher than the refractive index of the light diffusing agent, and is not particularly limited. A desired diffusivity (viewing angle) can be obtained by setting the refractive index difference in the light diffusion layer 14b within the above range.

  The volume ratio of the light diffusing agent in the light diffusion layer 14b (hereinafter sometimes abbreviated as the volume ratio in the layer) is preferably 10 to 60% by volume. In the case of the two-layer configuration, the volume ratios in the first light diffusion layer and the second light diffusion layer 14b are the same. By setting the volume ratio in the light diffusion layer 14b within the above range, a film that does not transmit light and has excellent scratch resistance can be obtained. The volume ratio in the layer is a value obtained by dividing the volume percentage of the light diffusing agent in the layer by the sum of the volume percentage of the light diffusing agent in the layer and the volume percentage of the matrix. The volume ratio in the layer can be obtained by observing a cross-sectional view of the light diffusion layer 14b by SEM or the like.

In the light diffusion plate 14 shown in FIG. 2, the total thickness of the light diffusion layers 14b is 1 μm to 5 mm, preferably 5 to 500 μm, in terms of the layer thickness after curing. If the film thickness of the light diffusion layer 14b is 5 to 500 μm, sufficient diffusion performance can be obtained, and the film thickness can be made uniform easily, so that the image does not become uneven.
Further, the visible light transmittance of the light diffusing plate 14 is preferably 75% or more, particularly 85% or more in terms of (JIS K7361-1 (1997)) in that the light from the light source is used without loss. In the light diffusion layer 14b, it is preferable that the light diffusing agent is uniformly dispersed in the matrix. The film thickness of the light diffusion layer 14b is preferably 10 to 300 [mu] m, particularly 20 to 200 [mu] m, because this characteristic is excellent and the entire transmission screen can be made thin.

  In the light diffusion layer 14b, the mass ratio of the light diffusing agent to the matrix (the mass of the light diffusing agent / the mass of the matrix) is preferably 0.01 to 3.0. If the mass ratio is within this range, sufficient diffusion performance can be obtained and the film thickness can be made uniform easily, so that there is no unevenness in the image. The mass ratio is more preferably 0.05 to 2.5, and particularly preferably 0.1 to 2 in terms of more excellent characteristics.

The light diffusion layer 14b can be formed by applying a light diffusion layer forming coating liquid (hereinafter also abbreviated as a coating liquid) in which a matrix forming component or a light diffusion agent is dispersed to the surface of the glass substrate 14a. it can. The coating is preferably performed separately for each coating solution.
The coating liquid is usually a composition in which a matrix-forming component or a light diffusing agent is dispersed in the liquid, and is preferably dispersed uniformly. The coating solution further contains a curing agent for curing the matrix-forming component, if necessary. The content of the curing agent in the coating solution is preferably 20% by mass or less, and preferably 10% by mass, because the properties as a diffusion plate are not impaired. Furthermore, the coating solution may contain other components as long as the object of the present invention is not impaired. Examples of the other components include a reinforcing agent, a dispersing agent, a surfactant that improves wettability to a base material, an antifoaming agent, and a leveling agent, which are components for improving adhesion to a substrate. The other component is preferably 10% by mass or less in the coating solution because the characteristics as the diffusion plate are not impaired. As the solvent used for the coating solution, a general-purpose solvent suitable for coating can be appropriately selected depending on the material.

  In the transmissive screen 10 ′ shown in FIG. 2, the light absorbing compound may be contained in any constituent member that can be an optical path of external light. Accordingly, all the modes described for the transmission screen 10 shown in FIG. 1 can be implemented. Further, in the case of the transmission type screen 10 ′ shown in FIG. 2, the light diffusion layer 14 b may contain a light absorbing compound.

  FIG. 3 is a view showing still another aspect of the transmissive screen of the present invention. The procedure for forming the light shielding layer 15 is different from that of the transmissive screen of FIG. In the transmissive screen 10 ″ shown in FIG. 3, the light shielding layer (black stripe) 15 is formed by the method described in JP-A-9-269546. As a result, the light shielding layer (black stripe) 15 is lenticular. It forms through the positive photosensitive adhesive 16 on the flat surface of the sheet | seat 12. In this case, the said positive adhesive 16 can also be made to contain a light absorption compound. When this is included, a layer containing a light absorbing compound is formed on the flat surface of the lenticular sheet, and a light shielding layer (black stripe) 15 is formed on the layer containing the light absorbing compound. For this reason, at the time of non-lighting, the blackness of the transmissive screen 10 is not impaired.

  In the present invention, a low reflection film or an antiglare film may be provided on the observer side surface (surface on the light exit side from the light source) of the transmissive screen 10, 10 ′, 10 ″. The film or the anti-glare film may be directly formed on the constituent members of the transmission screens 10, 10 ′, 10 ″, or may be bonded to the constituent members after being formed on the resin film. The film material may be polyethylene terephthalate resin (PET), polystyrene resin, acrylic resin, polycarbonate resin, vinyl chloride resin, or the like in terms of strength.

  As the low reflection film, a multilayer film in which a fluororesin and a film having a high and low refractive index of two or more layers are combined is suitable. As the high refractive index film, titanium oxide, niobium oxide, tantalum oxide, titanium nitride, and titanium oxynitride are preferable because of their high refractive index and excellent durability. As the low refractive index film, silicon oxide is preferable because of its low refractive index and excellent durability. As the film configuration of the multilayer film, for example, (1) two-layer system of component / titanium nitride or titanium oxynitride / silicon oxide, (2) component / titanium oxide or niobium oxide or tantalum oxide / silicon oxide / oxide Examples thereof include titanium, niobium oxide and tantalum oxide / silicon oxide four-layer systems.

  The anti-glare film is prepared by adjusting the solid content and matrix / particulate composition of the coating solution for forming the light diffusion layer described above, applying to the substrate, drying, and forming a concavo-convex film on the substrate, spraying a hydrolyzate of Si alkoxide It can be formed by a method of forming an uneven film on the substrate by coating and baking, a method of forming unevenness on the surface of the substrate by sandblasting or chemical etching, and the like.

Hereinafter, based on an Example, this invention is demonstrated more concretely. However, the present invention is not limited to this.
Example 1
In this embodiment, the transmission screen 10 shown in FIG. 1 is produced. In the transmission screen 10 shown in FIG. 1, the Fresnel lens sheet 11 and the light diffusion plate 14 (made of acrylate / styrene copolymer, thickness 2 mm) contain a predetermined amount of a light diffusion agent. The light diffusing plate 14 contains 0.01% by mass of a visible light absorbing dye (Red A-2G (perinone dye)) having a maximum absorption wavelength of 480 nm as a light absorbing compound.
The Fresnel lens sheet 11, the lenticular lens sheet 12, and the light diffusing plate 14 are laminated in this order from the light source side when the transmissive screen 10 is used.
The Fresnel lens sheet 11 and the lenticular lens sheet 12 are fixed by laminating them together with a double-sided tape. The lenticular lens sheet 12 and the light diffusing plate 14 are bonded via an adhesive layer 13 having a light shielding layer (black stripe) 15.
The evaluation method of the obtained transmission type screen is as follows.
(1) Average value of total light transmittance: The total light transmittance (in each wavelength region) of the obtained transmission screen 10 is measured according to JIS-K7105 (1981) measuring method B, and the average value is calculated. To do.
(2) Visual evaluation of contrast: The obtained transmissive screen 10 is incorporated into an RPTV. A projector (PJ-TX10J manufactured by Hitachi, Ltd.) is used as a light source for RPTV. The contrast is visually evaluated while white is displayed at the center of the screen and nothing is displayed around it. The evaluation is performed in a room where the three-wavelength light emitting daylight fluorescent lamp F10 is installed on the ceiling. The results are shown in Table 1.
In FIG. 7, the emission spectrum of the RPTV after passing through the transmission screen of Example 1 is indicated by a broken line B, and the emission spectrum of the three-wavelength region fluorescent lamp F10 is indicated by a broken line D. In FIG. 7, the emission spectrum of the RPTV before passing through the transmission screen of Example 1 is indicated by a solid line A, and the emission spectrum of the three-wavelength region fluorescent lamp F10 before passing through the transmission screen. Is shown by the solid line C. In FIG. 7, spectra A and C indicated by solid lines are the same as the emission spectrum of RPTV and the emission spectrum of F10 shown in FIG. 4, respectively. As is apparent from FIG. 7, when the transmission screen of Example 1 is transmitted, the emission spectrum of the three-wavelength region is compared with the emission spectrum of RPTV (solid line A (before transmission) −broken line B (after transmission)). It can be seen that the emission spectrum of the lamp F10 (solid line C (before transmission) −broken line D (after transmission)) is greatly reduced particularly near 450 nm. However, in FIG. 7, the emission spectrum (dashed line D) of the three-wavelength region fluorescent lamp F10 is obtained by transmitting the transmission screen twice.

(Example 2)
In this example, a transmissive screen 10 ′ shown in FIG. 2 was produced. In the transmissive screen 10 shown in FIG. 2, a light diffusion layer 14b is formed on a glass substrate 14a having a thickness of 3 mm. The light diffusing layer 14b has a film thickness of 40 μm, 55% by mass of a matrix component (polyester resin), 40% by mass of a light diffusing agent (acrylate / styrene copolymer fine particles), and a visible light having a maximum absorption wavelength of 480 nm as a light absorbing compound. It contains 0.3% by mass of a light absorbing dye (Red A-2G (perinone dye)).
The light diffusing layer 14b is a light diffusing layer in which a matrix forming component (polyester resin), a light diffusing agent (acrylate / styrene copolymer fine particles), a light absorbing compound (Red A-2G), and a curing agent (polyisocyanate) are dispersed. The forming coating solution was applied to the surface of the glass substrate 14a and then cured.
The Fresnel lens sheet 11, the lenticular lens sheet 12, and the light diffusing plate 14 are laminated in this order from the light source side when the transmissive screen 10 ′ is used.
The Fresnel lens sheet 11 and the lenticular lens sheet 12 are fixed by laminating them together and sticking the periphery together with a double-sided tape. The lenticular lens sheet 12, the light diffusing plate 14, and the adhesive layer 13 having a light shielding layer (black stripe) 15 are joined.
The obtained transmission screen was subjected to measurement of the average value of total light transmittance (in each wavelength range) and visual evaluation of contrast in the same procedure as in Example 1. The results are shown in Table 1.

(Example 3)
In this example, a transmissive screen 10 ″ shown in FIG. 3 was produced. In the transmissive screen 10 ″ shown in FIG. 3, Red A-2G as a light absorbing compound was added to the flat surface of the lenticular sheet 12 by 0.0. A positive photosensitive pressure-sensitive adhesive layer 16 containing 5% by mass is formed. A light shielding layer (black stripe) 15 is formed on the positive photosensitive adhesive layer 16, more specifically, on the non-light-condensing portion region of the lenticular sheet 12.
Further, in the transmissive screen 10 ″ shown in FIG. 3, a light diffusion layer 14b is formed on a glass substrate 14a having a thickness of 3 mm. The light diffusion layer 14b has a thickness of 40 μm and is a light diffusion agent. (Acrylate / styrene copolymer fine particles) 40% by mass and matrix component (polyester resin) 55% by mass are contained.

The light diffusion layer 14b is formed by applying a coating solution for forming a light diffusion layer in which a matrix forming component (polyester resin), a light diffusion agent (acrylate / styrene copolymer fine particles) and a curing agent (polyisocyanate) are dispersed to the surface of the glass substrate 14a. It was formed by coating and then curing.
The Fresnel lens sheet 11, the lenticular lens sheet 12, and the light diffusing plate 14 are laminated in this order from the light source side when the transmissive screen 10 is used.
The Fresnel lens sheet 11 and the lenticular lens sheet 12 are fixed by laminating them together with a double-sided tape. The lenticular lens sheet 12 and the light diffusing plate 14 are bonded via an adhesive layer 13 and a positive photosensitive adhesive layer 16.

In this embodiment, the light shielding layer (black stripe) 15 is formed on the flat surface of the lenticular lens sheet 12 through the positive photosensitive adhesive layer 16 by using the method described in JP-A-9-269546. To do. The formation of the light shielding layer (black stripe) 15 is performed according to the following procedure.
A positive photosensitive adhesive containing 2% by mass of Red A-2G is applied to the flat surface of the lenticular lens sheet 12 to form a positive photosensitive adhesive layer 16 (film thickness 5 μm).
Next, the lenticular lens sheet 12, more specifically, the lens surface of the sheet 12 is irradiated with ultraviolet rays from an ultraviolet irradiation device. Due to the condensing action of the lenticular lens, the portion of the positive photosensitive adhesive layer 16 where the ultraviolet rays were condensed lost the adhesiveness and became a non-adhesive portion. On the other hand, the part of the positive photosensitive pressure-sensitive adhesive layer 16 where the ultraviolet rays are not condensed maintains the adhesiveness (adhesive part). Subsequently, by passing the lenticular lens sheet 12 through a pair of laminating rolls, the black transfer layer (black powder toner) is transferred only from the transfer paper supplied from the rolls to the adhesive portion, and the light shielding layer (black stripe) 15 is formed. Form.
1 and 2 do not have a positive photosensitive adhesive layer, the transmission screens of Examples 1 and 2 have the same procedure as in Example 3. A light shielding layer (black stripe) 15 is formed. However, a positive photosensitive adhesive that does not contain a light absorbing compound (Red A-2G) is used.

  The obtained transmission screen was subjected to measurement of the average value of total light transmittance (in each wavelength range) and visual evaluation of contrast in the same procedure as in Example 1. The results are shown in Table 1.

(Comparative Example 1)
In this comparative example, a transmissive screen 10 ′ shown in FIG. 2 was produced. The transmissive screen of this comparative example is the same as the transmissive screen of Example 2 except that the light diffusion layer 14b contains only a light diffusing agent and does not contain a visible light absorbing dye as the light absorbing compound. is there. The obtained transmission screen was subjected to measurement of the average value of total light transmittance (in each wavelength range) and visual evaluation of contrast in the same procedure as in Example 1. The results are shown in Table 1.

(Comparative Example 2)
In this comparative example, a transmissive screen 10 ′ shown in FIG. 2 was produced. In the transmissive screen of this example, the light diffusion layer 14b is a light absorbing compound, and a visible light absorbing dye Orange G (manufactured by Nippon Kayaku Co., Ltd.) having a maximum absorption wavelength of 430 nm is used instead of Red A-2G. It is the same as that of the transmission type screen of Example 2 except containing it in the mass%. The obtained transmission screen was subjected to measurement of the average value of total light transmittance (in each wavelength range) and visual evaluation of contrast in the same procedure as in Example 1. The results are shown in Table 1.

実施例１〜３と比較例１，２との比較より明らかなように、４５０〜５２０ｎｍの光線透過率の平均値Ｙ１が４００〜４５０ｎｍの光線透過率の平均値Ｙ２および５２０〜５７０ｎｍの光線透過率の平均値Ｙ３より小さい本発明の透過型スクリーンは、コントラストが高く良好である。光拡散層１４ｂが最大吸収波長４３０ｎｍの可視光吸収染料を含有する比較例２は、光拡散層１４ｂに可視光吸収染料を含有させていない比較例１に比べるとコントラストが高いが、Ｙ２がＹ１よりも低いため、実施例１〜３に比べてコントラストが低下しており、透過光の色調変化が生じていた。

As apparent from the comparison between Examples 1 to 3 and Comparative Examples 1 and 2, the average value Y1 of the light transmittance of 450 to 520 nm is the average value Y2 of the light transmittance of 400 to 450 nm and the light transmission of 520 to 570 nm. The transmission type screen of the present invention, which is smaller than the average value Y3, has a high contrast and is good. Comparative Example 2 in which the light diffusion layer 14b contains a visible light absorbing dye having a maximum absorption wavelength of 430 nm has a higher contrast than Comparative Example 1 in which the light diffusion layer 14b does not contain a visible light absorbing dye, but Y2 is Y1. Therefore, the contrast was lower than in Examples 1 to 3, and the color tone of transmitted light was changed.

  The present invention provides a transmissive screen used for RPTV, which has a better contrast than conventional screens.

FIG. 1 is a schematic cross-sectional view showing one embodiment of the transmission screen of the present invention. FIG. 2 is a view showing another aspect of the transmission screen of the present invention, and the structure of the light diffusing plate is different from that of FIG. FIG. 3 is a view showing another aspect of the transmission screen of the present invention, and the procedure for forming the light shielding layer is different from that of the transmission screen of FIG. FIG. 4 shows the emission spectrum of RPTV and the emission spectrum of F10. FIG. 5 shows an emission spectrum of RPTV, an emission spectrum of F10, and an absorption curve of Red A-2G. FIG. 6 shows the emission spectrum of RPTV, the emission spectrum of F10, and the absorption curve of Orange SF-R. FIG. 7 shows the emission spectrum of RPTV and the emission spectrum of F10 before and after transmission through the transmission screen of Example 1.

Explanation of symbols

10, 10 ', 10 ": Transmission type screen 11: Fresnel lens sheet 12: Lenticular lens sheet 13: Adhesive layer 14: Light diffusion plate 14a: Glass substrate 14b: Light diffusion layer 15: Light shielding layer (black stripe)
16: Positive photosensitive adhesive layer

Claims (4)

  A transmissive screen for use in a rear projection type projection television, wherein an average value Y1 of light transmittance of 450 to 520 nm is an average value Y2 of light transmittance of 400 to 450 nm and an average value Y3 of light transmittance of 520 to 570 nm. A transmission screen characterized by being smaller.   The transmissive screen according to claim 1, wherein the constituent member of the transmissive screen contains a compound having a maximum absorption in a wavelength range of 450 to 520 nm.   The transmission screen according to claim 1 or 2, wherein the compound having the maximum absorption in the wavelength region of 450 to 520 nm is an anthraquinone dye or a perinone dye.   The transmission screen according to any one of claims 1 to 3, wherein a difference between the Y1 and the Y3 is 5 to 25%, and a difference between the Y1 and the Y2 is 5 to 20%.

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