JP2005283748A - Screen and filter manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission type screen on which high contrast images can be displayed by eliminating the adverse effect of outdoor daylight. <P>SOLUTION: A filter 9 that transmits light of a prescribed wavelength area corresponding to projected light and absorbs light of a visible wavelength area except light of the prescribed wavelength area is disposed between a Fresnel lens 1 and a lenticular lens 11. Such a filter 9 has reflection faces on both of its sides, at least one of which has high reflection properties to light of prescribed wavelength area, and is obtained by arranging selective reflection layers 3 at an angle of 45° to the axial direction of incident light and in the direction of light reflection, each selective reflection layer 3 being a selective reflection face which has high absorption properties to light of the visible wavelength area except the prescribed wavelength area. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transmissive screen for displaying a high-contrast image and a method for manufacturing a filter applied to the screen.

  In recent years, data projectors are widely used as a means for presenters to present materials in conferences and the like, and video projectors and movie film projectors are becoming popular in general households. In these projector apparatuses, light output from a light source is spatially modulated by a light valve to be image light, and this image light is projected onto a projection screen through an illumination optical system such as a lens.

  Some projector apparatuses of this type can display a color image, and white light including three primary colors red (Red = R), green (Green = G), and blue (Blue = B) as light sources. A lamp that emits light is used, and a transmissive liquid crystal panel is used as a light valve. In this projector device, the white light emitted from the light source is separated into red, green and blue light beams by the illumination optical system, and these light beams are converged on a predetermined optical path. These light beams are spatially modulated by the liquid crystal panel according to the image signal, the modulated light beams are combined as color image light by the light combining unit, and the combined color image light is enlarged and projected onto the projection screen by the projection lens. .

  Recently, as a projector device capable of displaying a color image, a narrow band three primary color light source, for example, a laser oscillator that emits narrow band light of each color of RGB three primary colors is used as a light source, and a diffraction grating type light valve (GLV) is used as a light valve. : Grating Light Valve) has been developed. In this projector apparatus, the light beams of the respective colors emitted from the laser oscillator are spatially modulated by the GLV in accordance with the image signal. The light beam thus modulated is combined as color image light by the light combining unit in the same manner as the projector device described above, and the combined color image light is enlarged and projected onto the projection screen by the projection lens.

  By the way, the projection screen used in the projector device includes a transmission method in which projection light is irradiated from the back side and viewed from the front side, and a reflection method in which projection light is irradiated from the front side and the reflected light is viewed from the front side. It is divided into. In any method, in order to realize a screen with good visibility, it is desired to obtain a bright and high-contrast image.

  In a conventional rear projector device, for example, a screen constituted by a Fresnel lens and a lenticular lens is used. In this configuration, the projection light from the projector is converted into parallel light by the Fresnel lens and further diffused left and right by the lenticular lens. Thereby, the observer observes the projected image as the transmitted light of the transmissive screen.

  However, the rear projector apparatus described above is generally used in a bright room, and in this case, external light such as room lighting is reflected on the surface of the lenticular lens, and this is observed together with the image light emitted from the screen. There has been a problem that the contrast of the image is lowered.

As a countermeasure, as shown in FIG. 9, in the lenticular lens 100 installed facing the Fresnel lens sheet 90, a screen is proposed in which a black stripe 105 is formed on the non-light-collecting part of the lens part in order to lower the black level. (For example, refer to Patent Document 1).
JP 2003-131325 A

  However, even in the screen having the above-described configuration, the black level cannot be sufficiently lowered due to external light entering through the gap between the black stripes being re-reflected on the surface of the Fresnel lens, and there is a limit to improving the contrast.

  The present invention has been made in response to the above-described problems of the prior art, and by providing a filter that transmits projection light and absorbs light in other wavelength regions, the influence of external light is eliminated, and a high-contrast image is obtained. An object of the present invention is to provide a transmissive screen that can be displayed.

  Another object of the present invention is to provide a method for manufacturing a filter that transmits light in a specific wavelength region and absorbs light in a visible wavelength region excluding the specific wavelength region.

  In other words, the screen according to the first aspect of the present invention is disposed between the Fresnel lens and the lenticular lens, the Fresnel lens that emits the projection light as substantially parallel light, the lenticular lens having a lens portion on the Fresnel lens side, A filter that transmits light in a specific wavelength region corresponding to projection light among light incident through a lens or a lenticular lens and absorbs light in a visible wavelength region excluding the specific wavelength region is provided. .

  In the present invention, the substantially parallel projection light emitted from the Fresnel lens passes through the filter, is emitted to the lenticular lens, and is observed as a projection image. On the other hand, external light that passes through the lenticular lens and enters as substantially parallel light is almost absorbed by a filter that absorbs light in a wavelength region excluding projection light. Therefore, there is almost no external light re-reflected on the surface of the Fresnel lens, and it is possible to display a high-contrast image with very little influence of external light.

  A filter having such optical characteristics is a reflective surface on both sides, and at least one of the reflective surfaces has a high reflection characteristic for light in a specific wavelength region, and for light in the visible wavelength region excluding the specific wavelength region. The selective reflection layer, which is a selective reflection surface having high absorption characteristics, is obtained by having a structure in which the selective reflection layer is inclined at an angle of about 45 degrees with respect to the light incident direction and arranged in the light reflection direction. In this structure, reflecting surfaces inclined at an angle of about 45 degrees face each other, and at least one of them is a selective reflecting surface, so that light in a specific wavelength region of parallel light incident on the filter is reflected by the facing reflecting surface. The light in the visible wavelength region excluding the specific wavelength region is absorbed by the selective reflection surface in the filter.

Such a selective reflection layer can be composed of an optical multilayer film composed of a dielectric film and a light-absorbing thin film having transparency, and a metal reflection film that reflects light transmitted through the optical multilayer film. In this case, the other reflection surface of the selective reflection layer is a mirror surface made of a metal reflection film. The dielectric film is formed by using a material transparent at least in the visible wavelength region, for example, Nb ₂ O ₅ , TiO ₂ , Ta ₂ O ₅ , Al ₂ O ₃ or SiO ₂ , for example, by a sputtering method. The light-absorbing thin film preferably has a thickness of 5 to 20 nm and has a refractive index of 1 or more and an absorption coefficient of 0.5 or more, such as Nb, Nb-based alloy, C, Cr, Fe, Ge, Ni, Pd, _{Pt, Rh, Ti, TiN,} TiN x W y, Mn, using Ru or PbTe, for example, it is formed by a sputtering method. The dielectric film can also be formed by a coating method or the like using a solvent-based material such as a thermosetting resin or a UV curable resin. The metal reflection film is made of a metal or an alloy such as Al or Ag having a high visible light reflectivity, and is formed using a dry process such as a vapor deposition method or a sputtering method.

  The selective reflection layer includes an optical multilayer film in which a high refractive index layer and a low refractive index layer having a lower refractive index are alternately stacked, an absorption layer that absorbs light transmitted through the optical multilayer film, and the absorption layer. It can also be constituted by a metal reflective film formed on the back surface of the substrate. Also in this case, the other reflection surface of the selective reflection layer is a mirror surface made of a metal reflection film. Furthermore, the selective reflection layer may have a configuration in which an optical multilayer film in which a high refractive index layer and a low refractive index layer having a lower refractive index are alternately stacked is disposed with an absorption layer interposed therebetween. In this case, both reflection surfaces of the selective reflection layer are selective reflection surfaces.

The high refractive index layer is formed of, for example, TiO ₂ , Nb ₂ O ₅ or Ta ₂ O ₅ , and the low refractive index layer is formed of, for example, SiO ₂ or MgF ₂ using, for example, a sputtering method. The high refractive index layer and the low refractive index layer can also be formed by a coating method or the like using a solvent-based material such as a thermosetting resin or a UV curable resin. The absorption layer is formed using, for example, a black paint. The carbon film can also be formed by a dry process such as a vapor deposition method or a sputtering method. The metal reflection film is formed in the same manner as described above.

  The structure in which the selective reflection layers of the filter are arranged can be formed by pasting together using a transparent substrate. In order to maintain the strength of the structure, a structure in which both surfaces are sandwiched between a Fresnel lens side and a lenticular lens side with a backup base material is recommended. Further, it is desirable to form an antireflection film on the surface of the backup base material so that light is not reflected on the surface of the filter.

  On the sheet surface of the lenticular lens, a stripe-shaped light absorption layer is preferably formed at a position (non-condensing part) other than the condensing part by the lens part. Thereby, the ratio of the external light passing through the lenticular lens can be reduced, and the external light incident from the condensing unit is converted into substantially parallel light by the lenticular lens and enters the filter.

  Further, a diffusion layer is formed on the sheet surface side opposite to the lens portion of the lenticular lens. Thereby, the projection light is diffused not only in the horizontal direction of the screen but also in the vertical direction, so that the visibility can be improved.

  The invention of claim 14 is a method for manufacturing a filter that transmits light in a specific wavelength region of incident parallel light and absorbs light in a visible wavelength region excluding the specific wavelength region, and both surfaces are reflective surfaces. The selective reflection layer, which is a selective reflection surface having at least one reflection surface having high reflection characteristics with respect to light in a specific wavelength region and having high absorption characteristics with respect to light in a visible wavelength region excluding the specific wavelength region, It has the process of forming the laminated body arranged through the transparent base material, and the process of slicing this laminated body at an angle of about 45 degree | times.

  In the invention of claim 14, it is possible to easily produce a filter having a structure in which selective reflection layers inclined at an angle of approximately 45 degrees are arranged via a transparent substrate.

  According to the invention of claim 1, by inserting a filter formed between the Fresnel lens and the lenticular lens so as to transmit the projection light and absorb the light in the other wavelength region, in the transmission type It is possible to obtain a screen that displays a high-contrast image with very little influence from outside light.

  According to the fourteenth aspect of the present invention, the both surfaces are reflective surfaces, and at least one of the reflective surfaces reflects light in a specific wavelength region and absorbs light in a visible wavelength region excluding the specific wavelength region. By forming and laminating a selective reflection layer on a transparent substrate, it is possible to easily manufacture a filter that transmits light in a specific wavelength region and absorbs light in a visible wavelength region excluding the specific wavelength region.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a horizontal cross section of a screen according to an embodiment of the present invention. From a projection light side, a Fresnel lens 1 and a selective reflection layer 3 are inclined through a transparent substrate 5 with an inclination angle of 45 °. The filter 9 is arranged and sandwiched between the backup base materials 7, the lenticular lens 11, the black stripe 13 formed in the non-condensing portion of the lenticular lens 11, and the diffusion plate 15.

  The Fresnel lens 1 receives the projection light Lp from the projector and emits it as substantially parallel light, and a concentric lens portion is formed on the emission side of the projection light Lp. Examples of the material include acrylic resin, polycarbonate, polyester, polystyrene, polyolefin, vinyl chloride resin, and polyimide.

  The filter 9 has a structure in which the selective reflection layers 3 are arranged at an angle of 45 ° with respect to the axial direction of incident light and are arranged via a transparent substrate 5. This structure is preferably sandwiched between backup substrates 7 in order to maintain its strength.

  The selective reflection layer 3 has a reflection surface that reflects at least light in a specific wavelength region, for example, light in the RGB three primary color wavelength region of the projection light Lp, on both surfaces, and at least one of the reflection surfaces has a wavelength region excluding the three primary color wavelength regions. This is a selective reflection surface that absorbs light. Such a selective reflection layer 3 includes, for example, a metal reflection film 31 as shown in FIG. 2, a dielectric film 33Di (i = 1, 2,...), And a light-absorbing thin film 33Mj (j = 1, 2) having transparency. ,...), And a laminated structure with the optical multilayer film 33.

  In this laminated structure, the metal reflection film 31 forms a mirror surface that totally reflects light incident from the transparent base material 5 side, and against the light incident from the optical multilayer film 33 side, the optical multilayer film The selective reflection surface is formed by reflecting the light transmitted through 33. As such a metal reflective film 31, a metal material having a substantially uniform reflectance in the visible wavelength region (380 nm to 780 nm), for example, a metal or an alloy such as Al or Ag is used. The film thickness needs to be a thickness that does not transmit light, and is preferably 50 nm or more. Such a metal reflective film 31 can be formed using a vapor deposition method, a sputtering method, or the like.

  The optical multilayer film 33 includes a dielectric film 33Di (i = 1, 2,...) And a light-absorbing thin film 33Mj (j = 1, 2,...) Having transparency, and at least the dielectric film 33D1 and the light-absorbing thin film 33M1. It has a laminated structure of two or more layers including The optical multilayer film 33 is formed on the metal reflection film 31 so that it has a high reflection characteristic with respect to light in a specific wavelength region of incident light, and is high with respect to light in other wavelength regions. A selective reflection surface having absorption characteristics can be formed.

The dielectric film 33Di is made of, for example, Nb ₂ O ₅ , TiO ₂ , Ta ₂ O ₅ , Al ₂ O ₃ or SiO ₂ , and is formed by using, for example, a sputtering method. The dielectric film 33Di may be a resin film that is transparent in the visible wavelength region. In this case, it can be formed by a coating method using a thermosetting resin that is cured by heat or ultraviolet rays. Each film thickness of the dielectric film 33Di is defined as follows: d is the thickness of each film, n is the refractive index of each film, and λ is the wavelength of light to be reflected among the light incident on the optical multilayer film 33. The optical thickness nd of each film is designed so as to satisfy the equation shown in Equation 1 for each wavelength λ.

(Equation 1)
nd = λ (α ± 1/4) (where α is a natural number)

The light-absorbing thin film 33Mj having transparency is formed of a material having a refractive index of 1 or more and an absorption coefficient of 0.5 or more. Examples of such materials include Nb, Nb-based alloys, C, Cr, Fe, Ge, Ni, Pd, Pt, Rh, Ti, TiN, TiN _x W _y , Mn, Ru, and PbTe. The film thickness is preferably in the range of 5 to 20 nm. If the thickness is less than 5 nm, sufficient light absorption cannot be obtained, and if it exceeds 20 nm, light transmittance may not be obtained. The light absorbing thin film 33Mj is formed by using, for example, a sputtering method.

As shown in FIG. 2, the selective reflection layer 3 composed of the optical multilayer film 33 and the metal reflection film 31 includes, for example, Al as the metal reflection film 31, Nb ₂ O ₅ as the dielectric film 33D1, and a light absorption thin film 33M1. Nb and Nb ₂ O ₅ for the dielectric film 33D2, the metal reflective film 31 has a thickness of 50 nm, the dielectric film 33D1 has a thickness of 551 nm, the light absorption thin film 33M1 has a thickness of 15 nm, and the dielectric film 33D2 As shown in FIG. 3, the reflection characteristic is indicated by a solid line, and the absorption characteristic is indicated by a dotted line. As shown in FIG. It is possible to obtain a selective reflection surface having a high absorption characteristic with an absorptance of 90% or more with respect to light in the above wavelength region. In this selective reflection layer 3, the optical multilayer film 33 is designed in accordance with a laser projector whose light source has three primary color wavelength regions of 457 nm (B), 532 nm (G), and 642 nm (R).

  In the selective reflection layer 3, the optical multilayer film 33 may have a two-layer structure of a dielectric film 33D1 and a light absorption thin film 33M1. In this case, the half-value width of the reflection peak in the three primary color wavelength regions is larger than in the case of the three-layer structure. That is, as the number of stacked optical multilayer films 33 increases, the half-value width of the reflection peak in the three primary color wavelength regions decreases. In addition, the half width of the reflection peak in the three primary color wavelength region also varies depending on the refractive index of the dielectric film 33D. The smaller the refractive index of the dielectric film 33D, the smaller the half width of the reflection peak in the three primary color wavelength region. The smaller the half width of the reflection peak in the three primary color wavelength regions, the lower the influence of external light and the higher the contrast, but the wider the viewing angle, the larger the half width of the reflection peak. For this reason, the optical multilayer film 33 is designed according to the light source and usage pattern of the projector.

  Further, the optical multilayer film 33 is not limited to the one in which the dielectric films 33D and the light absorption thin films 33M are alternately stacked. The dielectric film 33Di may be continuously formed of different dielectric materials in accordance with the intensity of light in the RGB three primary colors wavelength region of the projector light source.

  The transparent base material 5 and the backup base material 7 are preferably made of the same material. For example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), acrylic resin (PMMA) or the like is used. In addition, as the pressure-sensitive adhesive or the adhesive used when the transparent base material 5 and the backup base material 7 are bonded together, the same refractive index as that of the transparent base material 5 and the backup base material 7 is used. Thereby, reflection at the interface can be suppressed. Furthermore, in order to suppress the reflection of light on the surface of the filter 9, it is desirable to form the antireflection film on the backup base material 7 on the Fresnel lens 1 side and the lenticular lens 11 side, respectively.

  The structure in which the transparent base material 5 and the selective reflection layer 3 are arranged at an angle of 45 ° can be produced by the following procedure. First, the selective reflection layer 3 is formed on the transparent substrate 5. At that time, as shown in FIG. 4 (a), even if the selective reflection surface is formed from the metal reflective film 31, the stacking order is reversed as shown in FIG. 4 (b). Either may be sufficient even if it makes a mirror surface become upper. Next, as shown in FIG. 5, a plurality of the selective reflection films 3 formed on the transparent substrate 5 are laminated and bonded together, and then sliced at an angle of 45 °. The filter 9 is obtained by pasting the backup base material 7 on the cut surface obtained by slicing.

  Further, as shown in FIG. 6, the selective reflection layer 3 having a selective reflection surface and a mirror surface is formed by alternately arranging a high refractive index layer 37H and a low refractive index layer 37L via an absorption layer 35 on the metal reflection film 31. It can also be obtained by the configuration in which the optical multilayer film 37 laminated on is formed. The optical multilayer film 37 in the selective reflection layer 3 is designed to have a high reflection characteristic for light in the RGB three primary color wavelength regions and a high transmission characteristic for light in other wavelength regions. The number of stacked layers is preferably an odd number of three or more layers. Even in this configuration, the light incident from the metal reflective film 31 side is totally reflected, but the light incident from the optical multilayer film 37 side is in the RGB primary color wavelength region according to the optical characteristics as shown in FIG. Light is selectively reflected, and light in other wavelength regions is absorbed by the absorption layer 35.

The absorbing layer 35 is formed by applying a black paint, but a light absorbing material such as C can also be formed by vapor deposition, sputtering, or the like. The high refractive index layer 37H is made of TiO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ or the like, and the low refractive index layer 37L is made of SiO ₂ , MgF ₂ or the like. Such a high refractive index layer 37H and a low refractive index layer 37L are formed by, for example, a sputtering method. Alternatively, the high refractive index layer 37H and the low refractive index layer 37L can be formed by a coating method or the like using a solvent-based material such as a thermosetting resin or a UV curable resin. For example, the thermosetting resin JSR OPSTAR (JN7102: refractive index 1.68) is used as the material for the high refractive index layer 37H, and the thermosetting resin JSR OPSTAR (JN7215: refractive index) is used as the material for the low refractive index layer 37L. 1.41) can be used.

  The selective reflection layer 3 composed of the metal reflection film 31, the absorption layer 35, and the optical multilayer film 37 provides a selective reflection surface by the optical multilayer film 3 and the absorption layer 35. There are four methods (a) to (d) as shown in FIG. That is, in addition to the method of forming the selective reflection layer 3 on one side of the transparent substrate 5 as shown in FIGS. 7A and 7B, only the metal reflection film 31 is separated from the selective reflection layer 3 in FIG. As shown in FIG. 7C, a method of forming on the other surface of the transparent substrate 5 and a method of forming on one side of the other transparent substrate 5 as shown in FIG. Can take. In the method of FIG. 7C, black particles may be included in the pressure-sensitive adhesive or adhesive used for bonding instead of the absorbing layer 35. In the method of FIG. 7D, the thickness of the transparent substrate 5 is half that of the other methods, and the refractive index of the adhesive or adhesive used for bonding is the same as the refractive index of the transparent substrate 5. To.

  Further, as shown in FIGS. 8A to 8C, the metal reflective film 31 in FIGS. 7A to 7D may be replaced with an optical multilayer film 37. In this case, the filter 9 in which the selective reflection layers 3 that are selective reflection surfaces on both sides are arranged is obtained by overlapping and bonding.

  The lenticular lens 11 has a lens portion in which cylindrical lenses long in the vertical direction are arranged in the horizontal direction on the filter 9 side. Examples of the material include acrylic resin, polycarbonate, polyester, polystyrene, polyolefin, vinyl chloride resin, and polyimide. On the sheet surface on the opposite side of the lens portion, a black stripe 13 as a light absorbing layer is formed at a position other than the condensing portion by the lens, that is, a non-condensing portion.

  The diffusion plate 15 is installed adjacent to the black stripe 13 and is attached to the sheet surface of the lenticular lens 11. Examples of the diffusing plate 15 include a transparent body such as glass or polymer, in which spherical beads having a desired diameter of several μm to several mm are arranged. The method for arranging the beads may not be equal. Moreover, you may use the diffusion plate of a commercially available uneven structure.

Next, the operation of the screen having the above configuration will be described.
As shown in FIG. 1, the projection light Lp projected from a projector (not shown) is converted into substantially parallel light by the Fresnel lens 1 and enters the filter 9. In the filter 9, the selective reflection layer 3 whose at least one surface is a selective reflection surface is inclined and arranged at an angle of 45 °, and the selective reflection surface is designed to reflect light in the three primary color wavelength regions corresponding to the projection light Lp. Therefore, the projection light Lp is reflected not only on the mirror surface but also on the selective reflection surface and guided to the adjacent selective reflection layer 3, where it is similarly reflected and emitted in the direction of the lenticular lens 11. In this way, the projection light Lp from the Fresnel lens 1 passes through the filter 9 and is diffused forward of the screen by the lenticular lens 11 and the diffusion plate 15.

  On the other hand, part of the external light Lo incident from the front of the screen is absorbed by the black stripes 13, but part of the external light Lo is incident on the lenticular lens 11 through the black stripes 13, and becomes substantially parallel light by the lenticular lens 11. And enters the filter 9. In the filter 9, at least one of the reflection surfaces of the selective reflection layer 3 facing each other through the transparent base material 5 is a selective reflection surface, so that the external light Lo hits the selective reflection surface and is almost absorbed. Accordingly, the amount of external light that passes through the filter 9 and is reflected by the surface of the Fresnel lens 1 is extremely small.

  The selective reflection surface obtained by the optical multilayer film tends to shift the reflection wavelength to the short wavelength side as the incident angle increases. With the above configuration, the angle of light incident on the selective reflection surface is 45 °. Therefore, it is preferable to design the film thickness of the optical multilayer film by shifting the reflection wavelength slightly higher than the wavelength region of the projection light so that the projection light having an incident angle of 45 ° is effectively reflected in advance.

  As is clear from the above description, in the present embodiment, the projection light projected from the back surface is transmitted, while the external light incident from the front surface is absorbed by the black stripe and partially transmitted from the outside. Since light is also almost absorbed by the selective reflection surface inclined at an angle of 45 ° in the filter, it is possible to display a high-contrast image that is hardly affected by outside light. Such a transmissive screen can be applied to various projectors such as LCD projectors, laser projectors such as GLV projectors, and LED projectors. In particular, the light source's RGB three primary color wavelength regions are relatively steep and narrow band lasers. Great effect for projectors and LED projectors.

It is horizontal direction sectional drawing which shows the structure of the screen of one embodiment of this invention. It is sectional drawing which shows the laminated structural example of the selective reflection layer concerning this invention. It is a figure which shows the optical characteristic of the selective reflection surface of the selective reflection layer shown in FIG. It is sectional drawing which shows the example of formation of the selective reflection layer with respect to a transparent base material. It is a figure explaining the manufacturing method of the filter concerning the present invention. It is sectional drawing which shows the other laminated structural example of the selective reflection layer concerning this invention. It is sectional drawing which shows the example of formation of the other selective reflection layer with respect to a transparent base material. It is sectional drawing which shows the example of formation of the further another selective reflection layer with respect to a transparent base material. It is sectional drawing which illustrates the conventional transmissive screen.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fresnel lens, 3 ... Selective reflection layer, 5 ... Transparent base material, 7 ... Backup base material, 9 ... Filter, 11 ... Lenticular lens, 13 ... Black stripe, 15 ... Diffuser

Claims (22)

A Fresnel lens that emits projection light as substantially parallel light;
A lenticular lens having a lens portion on the Fresnel lens side;
Visible wavelength that is installed between the Fresnel lens and the lenticular lens, transmits light in a specific wavelength region corresponding to the projection light out of light incident through the Fresnel lens or lenticular lens, and excludes the specific wavelength region A screen comprising a filter that absorbs light in the region.   The filter is a reflective surface on both sides, and at least one of the reflective surfaces has a high reflection characteristic for light in the specific wavelength region, and a high absorption characteristic for light in the visible wavelength region excluding the specific wavelength region. The screen according to claim 1, wherein the selective reflection layer, which is a selective reflection surface having an inclination, has a structure in which the selective reflection layer is inclined at an angle of about 45 degrees with respect to the light incident direction and is arranged in the light reflection direction. .   The selective reflection layer includes an optical multilayer film composed of a dielectric film and a light-absorbing thin film having transparency, and a metal reflection film that reflects light transmitted through the optical multilayer film. 2. The screen according to 2.   4. The screen according to claim 3, wherein the light absorbing thin film is made of a material having a refractive index of 1 or more and an absorption coefficient of 0.5 or more. Material of the light-absorbing thin film has a characteristic Nb, Nb alloys, C, Cr, Fe, Ge , Ni, Pd, Pt, Rh, Ti, TiN, TiN x W y, Mn, that is Ru or PbTe The screen according to claim 4. The screen according to claim 3, wherein the dielectric film is made of Nb ₂ O ₅ , TiO ₂ , Ta ₂ O ₅ , Al ₂ O _3, or SiO ₂ .   The selective reflection layer includes an optical multilayer film in which a high refractive index layer and a low refractive index layer having a lower refractive index are alternately laminated, an absorption layer that absorbs light transmitted through the optical multilayer film, and the absorption layer The screen according to claim 2, further comprising a metal reflective film laminated on the screen.   3. The selective reflection layer is provided with an optical multilayer film in which a high refractive index layer and a low refractive index layer having a lower refractive index are alternately stacked on both sides of an absorption layer. Screen described. The high refractive index layer is made of _TiO 2, _Nb 2 _{O 5} or _Ta 2 _{O 5,} screen according to claim 7 or 8, wherein the low refractive index layer is characterized in that it consists of SiO ₂ or MgF _2.   The filter includes a structure in which the selective reflection layer is arranged via a transparent base material, and a transparent backup base material that sandwiches the structure from the Fresnel lens side and the lenticular lens side. Item 3. The screen according to Item 2.   The screen according to claim 10, wherein the filter has an antireflection film formed on a surface of the backup base material.   2. The screen according to claim 1, wherein the lenticular lens has a stripe-shaped light absorption layer formed on a sheet surface opposite to the lens portion at a position other than the light collecting portion formed by the lens portion.   The screen according to claim 1, wherein the specific wavelength region includes each wavelength region of red light, green light, and blue light. A method of manufacturing a filter that transmits light in a specific wavelength region out of incident parallel light and absorbs light in a visible wavelength region excluding the specific wavelength region,
Both surfaces are reflective surfaces, and at least one of the reflective surfaces has high reflection characteristics for light in the specific wavelength region, and selective reflection that has high absorption characteristics for light in the visible wavelength region excluding the specific wavelength region. A step of forming a laminate in which the selective reflection layer as a surface is arranged via a transparent substrate;
And a step of slicing the laminate at an angle of approximately 45 degrees.   The method for producing a filter according to claim 14, further comprising a step of bonding a transparent backup base material to both cut surfaces of the sliced laminate.   The selective reflection layer includes an optical multilayer film made of a dielectric film and a light-absorbing thin film having transparency, and a metal reflection film that reflects light transmitted through the optical multilayer film. 14. The method for producing a filter according to 14.   The method of manufacturing a filter according to claim 16, wherein the light absorption thin film is made of a material having a refractive index of 1 or more and an absorption coefficient of 0.5 or more. Material of the light-absorbing thin film has a characteristic Nb, Nb alloys, C, Cr, Fe, Ge , Ni, Pd, Pt, Rh, Ti, TiN, TiN x W y, Mn, that is Ru or PbTe The method for manufacturing a filter according to claim 17. The dielectric _{film, Nb 2 O 5, TiO 2} , Ta 2 O 5, Al 2 O 3 or manufacturing method of the filter of claim 16, wherein the composed of SiO _2.   The selective reflection layer includes an optical multilayer film in which a high refractive index layer and a low refractive index layer having a lower refractive index are alternately laminated, an absorption layer that absorbs light transmitted through the optical multilayer film, and the absorption layer 15. The method of manufacturing a filter according to claim 14, further comprising a metal reflective film laminated on the substrate.   15. The selective reflection layer is provided with an optical multilayer film in which a high refractive index layer and a low refractive index layer having a lower refractive index are alternately stacked on both sides of an absorption layer. The manufacturing method of the filter of description. The method for manufacturing a filter according to claim 20 or 21, wherein the high refractive index layer is made of TiO ₂ , Nb ₂ O ₅ or Ta ₂ O ₅ , and the low refractive index layer is made of SiO ₂ or MgF ₂ .

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