JPH11344769A - Back projection type screen and production of light diffusion member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent back projection type screen which is capable of embodying a fine lenticular lens pitch having no possibility of generation of a moire fault and is excellent in reduction of the reflection of external light, and a process for producing a light diffusion member that the back projection type screen is provided with. SOLUTION: The back projection type screen has a light paralleling member for converting projected light to approximately parallel light and the light diffusion member 6 (7, 8) for diffusing the approximately parallel light to a perpendicular direction and a horizontal direction. In the light diffusion member 6, lenticular lenses 71 having the horizontal direction in its longitudinal direction are formed on a light incident surface. Black stripes 72 having the horizontal direction in their longitudinal direction are disposed in the light opaque sections existing near the foci of the lenticular lenses 71. The lenticular lenses 81, 82 having a perpendicular direction in their longitudinal direction are formed at a light exit surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear projection type screen (hereinafter, referred to as a rear projection type screen) used for constructing an image display device for magnifying and projecting an image displayed on a CRT or a liquid crystal panel from the back and observing the image from the front. , Screen)
And a method of manufacturing a light diffusing member provided in the screen.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for large screens centering on TV receivers, and a rear projection type image display apparatus has attracted attention because such a demand can be realized in a relatively lightweight and compact form. In general, such an image display device uses a CRT as an image source, but it is more preferable to use a dot matrix display device such as a small liquid crystal panel or a micromirror device as a light modulation element. A dot matrix display device having these features is expected as a multimedia display because it can be lightweight and compact and can display clear characters over every corner of the screen. Therefore, a basic configuration of an image display device when a transmission type liquid crystal panel is used as a light modulation element will be described based on a schematic explanatory diagram shown in FIG.

Light emitted from a lamp 1 is spatially modulated by a liquid crystal panel 2 and is projected by a projection lens 3 onto a screen 4.
Projection is enlarged. The screen 4 is provided on the image plane, and converges divergently incident light on the macro and diffuses incident light with directional sharpness on the macro, and then observes images from various angles. It has a function that enables A Fresnel lens sheet 5 is generally used as a light collimating member that converges the projection light into macro light and converts the light into substantially parallel light, and the light exit side of the Fresnel lens sheet 5, that is, the light on the observation side. A diffusion member 6 is provided. Therefore, the visual field characteristics of the image display device are determined by the diffusion characteristics of the light diffusion member 6.

[0004] By the way, the wider the visual field characteristics, the better. However, as the visual field characteristics become wider, the front luminance decreases. Therefore, it is important to effectively distribute light to a necessary area. In other words, in a general viewing environment, viewing from various angles is assumed in the horizontal direction, but in the vertical direction, the visual field is such that there is no large luminance variation within the range of the viewer standing and sitting. The screen 4 needs to have anisotropic diffusion characteristics that are wide in the horizontal direction and narrow in the vertical direction. Specifically, when expressed as an angle at which the luminance observed from the front direction of the viewing angle becomes half the luminance, that is, a so-called luminance half-value angle, the luminance half-value angle in the horizontal direction requires a range of ± 30 ° to ± 40 °. On the other hand, the vertical luminance half-value angle is ±
It is appropriate that the angle is in the range of 6 ° to ± 10 °.

From the viewpoint of realizing the anisotropic diffusion characteristic of the screen 4, it is common to use a light diffusion member 6 having a lenticular lens whose longitudinal direction is the vertical direction. The light diffusion member 6 obtains a large diffusion characteristic in the horizontal direction and obtains a relatively small diffusion characteristic in the vertical direction only by the action of the diffusion material disposed inside. Further, such a light diffusing member 6
Is mainly used in two methods, one of which is a light diffusion member in which a lenticular lens is formed on a light incident surface, a so-called lenticular lens sheet 61, and the other is Is a lenticular lens sheet 62 having a lenticular lens formed on the light exit surface. First, a lenticular lens sheet 61 in which a lenticular lens 611 having a vertical direction as a longitudinal direction is formed on a light incident surface will be described with reference to FIGS. 8 and 9.
In these figures, reference numeral 612 denotes a black stripe, and the ray trajectory is shown by a broken line in FIG.

As is apparent from these figures, substantially parallel light incident with extremely sharp directivity is largely diffused in the horizontal direction by the action of the lenticular lens 611 having the vertical direction as the longitudinal direction. The image can be observed from a wide viewing range. However, in this case, the substantially parallel light is emitted only from a specific part near the focal point of the lenticular lens 611, and is not emitted from other parts. Therefore, by utilizing such an operation, a black stripe 612 made of a light absorbing material is formed in a light non-transmitting portion on the light emitting surface of the lenticular lens sheet 61. When the black stripe 612 is not formed, a component is generated in which external light incident from the observation side is totally reflected by the lenticular lens 611, so that the contrast is significantly impaired.

In this case, the black stripe 6
In order to effectively secure the function of the lenticular lens 612, the black stripe 612 corresponds to the position facing the valley of the lenticular lens 611, that is, the black stripe 612 corresponds to the light non-transmitting portion which is the peak on the light exit surface of the lenticular lens sheet 61. It is necessary to form them at each of the positions where the light is to be emitted. If there is a positional deviation between them, light rays to be emitted are absorbed, resulting in a decrease in light efficiency. Then, in order to form the black stripes 612 at each accurate position facing the valley of the lenticular lens 611, when the lenticular lens sheet 61 is extruded or pressed, the lenticular lens sheet 6 is formed.
The irregularities alternately opposed to the irregularities on the first light incident surface are integrally formed on the light emitting surface of the lenticular lens sheet 61, and these irregularities are used.

Further, in order for the black stripe 612 to function effectively, the light exit surface of the lenticular lens sheet 61 must be provided for a light non-transmissive portion located near the focal point of the lenticular lens 611.
The thickness t of the lenticular lens sheet 61 is set so that the exit surface is located at a position substantially equal to the vicinity of the focal point of the lenticular lens 611.
Furthermore, a predetermined viewing angle (luminance half-value angle in the horizontal direction ± 30)
To 40 °), the pitch p of the lenticular lens 611 needs to be 0.6 times or more of the focal length. Therefore, the pitch p of the lenticular lens 611 is equal to the thickness t of the lenticular lens sheet 61. It is generally set to be 0.6 times or more of.

On the other hand, the lenticular lens sheet 62 in which the lenticular lens is formed on the light emitting surface has a configuration as shown in FIGS. 10 and 11, and a broken line in FIG. 11 indicates a ray trajectory. That is, when a configuration in which a lenticular lens is formed on the light exit surface is employed, a predetermined viewing angle (half-luminance angle in the horizontal direction ± 30 ° to 40 °) belongs only by the refraction of the lenticular lens. Therefore, a combination of the refractive lenticular lens 621 and the reflective lenticular lens 622 is used. When these lenticular lenses 621 and 622 are formed on the light emitting surface of the lenticular lens sheet 62, total reflection of external light does not occur even if no black stripe is provided.
In the lenticular lens sheet 62, the pitch of the lenticular lenses 621 and 622 can be set independently of the thickness of the lenticular lens sheet 62.

[0010]

However, the lenticular lens sheet 61 having the lenticular lens 611 formed on the light incident surface has a lenticular lens pitch p.
Is considered to be limited by the thickness t of the lenticular lens sheet 61. That is,
Despite the limit of the thickness t that can be formed by extrusion or pressing of the resin is about 0.6 mm, the lenticular lens pitch p for realizing the half-luminance angle in the horizontal direction is 0.6 times the thickness t. The minimum value of the lenticular lens pitch p is 0.36 m
m.

However, the minimum value of the lenticular lens pitch p of 0.36 mm is a sufficient value as long as the image source is a CRT. However, when a dot matrix display device is used as a light modulation element as an image source, The moiré failure occurs due to the periodicity of the pixel and the lenticular lens. According to the study of the inventors of the present invention, it has been found that while the screen size of 40 inches or more is ensured due to the characteristics of the rear projection type image display device that can easily be enlarged, the definition of the dot matrix display is improved. It has been confirmed that the lenticular lens pitch p required to avoid moiré obstruction when employing the most common VGA (640 × 480) display is about 0.2 mm or less. However, as long as the lenticular lens pitch p is larger, it is necessary to optimize the lenticular lens pitch p in accordance with the pixel pitch, and at present it is difficult to use it for general purposes.

On the other hand, in the lenticular lens sheet 62 in which the refraction type lenticular lens 621 and the reflection type lenticular lens 622 are formed on the light emitting surface, the lenticular lens pitch has a lenticular lens pitch.
Can be set irrespective of the thickness of the lens, it is easy to make the lenticular lens pitch finer to 0.2 mm or less. However, the lenticular lenses 621 and 62
In the configuration in which 2 is arranged on the light emission side of the lenticular lens sheet 62, it is impossible to concentrate the projection light on a specific area of the light emission surface, and it is not possible to form a black stripe without causing light loss Therefore, although there is no total reflection of external light even without the black stripe, the contrast of the lenticular lens sheet 61 having the black stripe 612 is greatly reduced with respect to external light. Therefore, the lenticular lenses 621 and 622 are
When adopting the configuration formed on the light emitting surface of No. 2, it is necessary to reduce the reflection of external light by adding a light absorbing material to the inside of the light emitting surface. There is a disadvantage that loss is caused and the light efficiency is reduced.

The present invention has been made in view of these inconveniences, and it is possible to realize a fine lenticular lens pitch which does not cause Moire trouble and is excellent in reducing reflection of external light. And a method for manufacturing a light diffusing member provided in the screen.

[0014]

According to a first aspect of the present invention, there is provided a screen comprising: a light collimating member for converting projection light into substantially parallel light; and a light diffusing member for diffusing substantially parallel light in a vertical direction and a horizontal direction. And the light diffusing member has a lenticular lens having a horizontal direction as a longitudinal direction formed on a light incident surface,
A black stripe having a horizontal direction as a longitudinal direction is provided at a light non-transmissive portion located near a focal point of the lenticular lens, and a lenticular lens having a vertical direction as a longitudinal direction is formed on a light emitting surface. It is characterized by. According to this configuration, since the lenticular lens for obtaining a relatively large diffusion angle in the horizontal direction is formed on the light exit surface of the screen, the pitch of the lenticular lens can be miniaturized. The external light can be effectively absorbed by the black stripes. It should be noted that light loss does not occur due to the black stripe.

According to a second aspect of the present invention, there is provided a screen, comprising: a light collimating member for converting projection light into substantially parallel light; a horizontal light diffusing member for mainly diffusing substantially parallel light in a horizontal direction; A vertical light diffusing member for mainly diffusing the light in the vertical direction, the horizontal light diffusing member has a flat light incident surface, and a lenticular lens having a vertical direction as a longitudinal direction is formed on the light emitting surface. On the other hand, the vertical light diffusing member is a light non-transmissive part in which a lenticular lens having a horizontal direction as a longitudinal direction is formed on a light incident surface, and a black stripe having a horizontal direction as a longitudinal direction is located near a focus of the lenticular lens. It is characterized by being provided in. According to this configuration, since the black stripes are provided, it is possible to realize a screen having high light efficiency with small contrast deterioration with respect to external light while maintaining a fine lenticular lens pitch without generating moiré trouble. Becomes possible.

According to a third aspect of the present invention, there is provided a method of manufacturing a light diffusing member provided in a rear projection type screen according to the first aspect of the present invention. Lenticular lens is formed,
A step of producing a vertical light diffusing member having a thickness substantially equal to the focal length of the lenticular lens and a black stripe provided on the light non-transmitting portion on the other surface located near the focal point of the lenticular lens, and a vertical direction on one surface A lenticular lens having a longitudinal direction is formed, and the other surface is a step of producing a flat horizontal light diffusion member, and the other surface provided with the black stripe of the vertical light diffusion member and the other flat surface of the horizontal light diffusion member. In which the longitudinal directions of the lenticular lenses are orthogonal to each other and are optically coupled to each other. According to this method, it is possible to easily manufacture a screen having high light efficiency, with a small lenticular lens pitch that does not cause moiré trouble, but with a small deterioration in contrast to external light.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIG. 1 is a partially cutaway perspective view showing the entire structure of a screen according to Embodiment 1, and FIG. 2 is a view along a vertical direction of the screen according to Embodiment 1. FIG. 3 is a cross-sectional view showing a cutting state, and FIG. 3 is a cross-sectional view showing a cutting state along a horizontal direction of the screen according to the first embodiment. Note that the broken line in the figure indicates the ray trajectory. By the way, the screen according to the present embodiment is C
It is used to configure a rear projection type image display device in which an image displayed on an RT or a liquid crystal panel is enlarged and projected from the back and observed from the front. The entire structure of the image display device is a conventional one. Since it is not fundamentally different from the above, it is assumed that the screen 4 shown in FIG. 7 is replaced with the screen 4 according to the present embodiment, that is, the screen 4 including the light diffusing member 6 described below. In the following, description of the image display device itself is omitted.

The screen 4 according to the first embodiment has the structure shown in FIG.
3, a Fresnel lens sheet 5 as a light collimating member for converting the projected light into substantially parallel light, and a light diffusing member 6 for diffusing substantially parallel light in the vertical and horizontal directions. The light diffusing member 6 here
Has a vertical light diffusing member 7 located on the Fresnel lens sheet 5 side and a horizontal light diffusing member 8 located on the observation side. The vertical light diffusing member 7 has a lenticular lens 71 having a horizontal direction as a longitudinal direction formed on a light incident surface, and a black stripe 72 having a horizontal direction as a longitudinal direction.
Is a lenticular lens sheet provided at a light non-transmissive portion of the light exit surface located near the focal point of the lenticular lens 71. Reference numeral 73 in FIG. 2 indicates a light transmitting portion on the light emitting surface of the vertical light diffusing member 7, that is, an opening portion.

By the way, the half-luminance angle in the vertical direction is from 6 ° to 6 °.
The diffusion angle due to the refraction of the lenticular lens 71 is set to 6 ° to 15 ° so that the viewing angle becomes 15 °, and the focal length with respect to the lenticular lens pitch p, that is, the thickness t of the vertical diffusion member 7 is: The value is adjusted so that the value t / p obtained by dividing the thickness t by the lenticular lens pitch p is about 7 to 3. Therefore, if the thickness t of the vertical diffusion member 7 is set to 0.6 mm, which is the minimum value at which resin molding is possible, the lenticular lens pitch p is 0.09 mm to 0.2 mm.
This means that the pitch is about 2 mm, so that even when a dot matrix display device is used as a light modulation element, a fine pitch free from moiré failure can be secured.
In addition, since the width of the black stripe 72 is preferably as large as possible from the viewpoint of reducing external light reflection, light loss does not cause a problem with various error factors such as light diffusivity and incident angle error. The width dimension of the black stripe 72 is set to be about 50% of the lenticular lens pitch p of the vertical light diffusion member 7.

On the other hand, in this case, the horizontal light diffusing member 8
Is a lenticular lens sheet in which a refractive lenticular lens 81 and a reflective lenticular lens 82 having a vertical direction as a longitudinal direction are formed on a light emitting surface, a light incident surface is a flat lenticular lens sheet, and a black stripe 72 is provided. The light emitting surface of the vertical light diffusing member 7 and the flat light incident surface of the horizontal light diffusing member 8 are joined and integrated with each other by a transparent optical coupling layer 9. That is, in this case, since each of the refractive lenticular lens 81 and the reflective lenticular lens 82 formed on the light emitting surface of the horizontal light diffusing member 8 has the vertical direction as the longitudinal direction, the pitch of the lenticular lens is equal to the horizontal light diffusing member. 8, the lenticular lens pitch can be set to about 0.2 mm to prevent moiré failure even when a dot matrix display device is used as a light modulation element.

Accordingly, the lamp 1 constituting the image display device is
Is projected from the liquid crystal panel 2 and the projection lens 3, and is converted into substantially parallel light by the Fresnel lens sheet 5 provided on the screen 4.
The substantially parallel light is refracted by the action of a lenticular lens 71 formed on the light incident surface of the vertical light diffusing member 7 and a black stripe 72 provided in a light non-transmissive portion located near the focal point of the lenticular lens 71. Opening 7 of the vertical light diffusing member 7 without being absorbed by
3 and is emitted after being diffused in the vertical direction. The light diffused in the vertical direction by the vertical light diffusing member 7 is diffused in the horizontal direction by the refraction lenticular lens 81 and the reflection lenticular lens 82 formed on the light exit surface of the horizontal light diffusion member 8. After that, it comes out.

Further, in the screen 4 according to the present embodiment, the light emitting surface of the vertical light diffusing member 7 and the flat light incident surface of the horizontal light diffusing member 8 are integrally joined by an optical coupling layer 9. Therefore, the light emitted from the vertical light diffusing member 7 does not reflect on the bonding surface, and the horizontal diffusing element 8
Is absorbed by the black stripe 72 at a stage before the reflection by the interface with the air occurs, so that the advantage that the amount of reflected light on the observation side is attenuated is obtained. Further, with the screen 4 configured as described above, it is possible to greatly reduce the reflection of external light by the light absorption effect of the black stripe 72, and the reduction effect is the same as that of the conventional screen shown in FIG. Is almost equal to the case where a light absorbing material having a transmittance of 50% is added in the configuration according to the above, the advantage that the light transmission efficiency can be increased to about twice is secured.

Furthermore, if an appropriate amount of light diffusing material is dispersed inside the horizontal light diffusing member 8, the lenticular lens 8
Thus, an effect of diffusing light to a region where the action of the light emitting device does not reach 1,82 to smooth the light distribution characteristics and an effect of alleviating the glare of the image can be obtained. Since the angle is about 2 ° to 3 °, compared to the lenticular lens sheet 62 shown in the conventional form, that is, the lenticular lens sheet 62 in which all the vertical diffusion depends on the action of the light diffusion material, the light diffusion material An advantage is obtained in that it is possible to improve the resolution while significantly reducing the amount of dispersion. In addition, even when the light diffusion material is dispersed inside the vertical diffusion member 7, it is possible to reduce the glare while smoothing the light distribution characteristics, but the component absorbed by the black stripe 72 may be reduced. Since light loss occurs due to being generated in the substantially parallel light to be diffused, the light diffusion material is dispersed only inside the horizontal light diffusion member 8 after the vertical light diffusion member 7 is made transparent. This is more preferable in practical use.

The light diffusing member 6 provided in the screen 4 according to the present embodiment is manufactured according to the following procedure, although not shown. That is, a mold having a shape opposite to the lenticular lens 71 at a constant pitch and a mold having a land shape having the same pitch are prepared, and the valleys and lands of the molds are opposed to each other. In addition to accurate alignment, the diffusion range is from 6 ° to 15 ° depending on the refractive index of the material used
After adjusting the gap between the pair of molds so that the thickness of the lenticular lens sheet becomes substantially equal to the focal length of the lenticular lens, a transparent resin material having excellent moldability such as PMMA (acrylic) or polycarbonate is formed. Extrusion roll molding or press molding is performed after use. Then, a lenticular lens 71 having a horizontal direction as a longitudinal direction is formed on one surface serving as a light incident surface, and the thickness t is substantially equal to the focal length of the lenticular lens 71, and the light located near the focal point of the lenticular lens 71 is formed. A lenticular lens sheet in which a land is formed on the light non-transmitting portion on the other surface that is the exit surface is obtained, and when black ink serving as a black stripe 72 is printed on the land of the lenticular lens sheet,
This means that the vertical light diffusion member 7 has been manufactured.

Next, a pair of molds having a shape suitable for manufacturing the horizontal light diffusing member 8, that is, the light of the horizontal light diffusing member 8 on which the refraction lenticular lens 81 and the reflection lenticular lens 82 are formed. Prepare a mold having a shape matching the emission surface and a mold having a shape matching the flat light incidence surface, and use a glass or glass with a high refractive index for a transparent resin material such as PMMA or polycarbonate. After preparing a resin material in which resin beads and the like are dispersed, the resin material is injected between molds that are positioned opposite to each other, and then cured. The lenticular lens 81 having the longitudinal direction is formed, and the other surface, which is the light emitting surface, is made flat to produce the horizontal light diffusing member 8. Subsequently, a transparent adhesive is applied to the entire surface of the light emitting surface of the vertical diffusion member 7 where the black stripe 72 is provided, and the light emitting surface of the vertical light diffusion member 7 where the black stripe is provided and the horizontal light diffusion member. When the flat light incident surface 8 and the lenticular lenses 71, 81, 82 are orthogonal to each other and optically coupled to each other, and then joined and cured, This means that the integrated light diffusion member 6 has been manufactured.

(Embodiment 2) FIG. 4 is a partially cutaway perspective view showing the entire structure of a screen according to Embodiment 2, and FIG. 5 shows a screen cut along a vertical direction according to Embodiment 2. FIG. 6 is a cross-sectional view showing a screen cut along a horizontal direction according to the second embodiment. The screen 4 according to the present embodiment is also replaced with the screen 4 shown in FIG. 7, as in the first embodiment.

The screen 4 according to the second embodiment has the structure shown in FIG.
As shown in FIG. 6 to FIG. 6, a Fresnel lens sheet 5 as a light parallelizing member for converting the projected light into substantially parallel light, and a horizontal light diffusing member 8 for mainly diffusing substantially parallel light in the horizontal direction.
And a vertical light diffusing member 7 for mainly diffusing the light diffused in the horizontal direction mainly in the vertical direction. The horizontal light diffusing member 8 here has a flat light incident surface and a vertical direction. A refractive lenticular lens 81 and a reflective lenticular lens 82 having a longitudinal direction are formed on a light emitting surface, and a light incident surface is a flat lenticular lens sheet. In this case, the vertical light diffusing member 7
Is a lenticular lens 71 having a horizontal direction as a longitudinal direction.
Is a lenticular lens sheet provided on a light incident surface, and a black stripe 72 having a horizontal direction as a longitudinal direction is provided at a light non-transmissive portion of a light exit surface located near a focal point of the lenticular lens 71. ing.

That is, the screen 4 according to the present embodiment has the horizontal light diffusing member 8 located on the Fresnel lens sheet 5 side and the vertical light diffusing member 7 located on the observation side. The vertical light diffusing member 7 and the horizontal light diffusing member 8 are not optically coupled, but have a configuration in which they are arranged in parallel with an air layer of a predetermined thickness interposed therebetween. Thus, in the screen 4 according to the second embodiment, although the interface with the air layer is increased and light reflection loss is caused as compared with the first embodiment, it is inevitable that the light efficiency is deteriorated. It has a simpler configuration in that it does not require a light absorbing material, and has an advantage that a large reflection reduction effect can be obtained as compared with the conventional configuration in which a light absorbing material needs to be added inside. Has become.

[0029]

According to the screen according to the first aspect of the present invention, since the lenticular lens capable of obtaining a relatively large diffusion angle in the horizontal direction is formed on the light exit surface of the screen, the lenticular lens pitch can be sufficiently increased. As a result, even when a dot matrix display device is used as an image source, moire trouble does not occur, and an effect that general use can be realized is obtained. According to the screen of the second aspect of the present invention, it is possible to realize a screen having a high light efficiency with a small contrast deterioration with respect to external light while maintaining a fine lenticular lens pitch that does not cause moire trouble. Is obtained.
Further, according to the method of manufacturing the light diffusing member according to claim 3 of the present invention, the deterioration of contrast with respect to external light can be small, and the light efficiency is high, even though the pitch is a fine lenticular lens that does not cause a moire problem. The effect is obtained that the screen can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing the entire configuration of a screen according to a first embodiment.

FIG. 2 is a cross-sectional view showing a cut state along a vertical direction of the screen according to the first embodiment.

FIG. 3 is a cross-sectional view showing a cut state along the horizontal direction of the screen according to the first embodiment.

FIG. 4 is a perspective view showing the entire configuration of the screen according to the second embodiment, partially cut away;

FIG. 5 is a cross-sectional view showing a cut state along a vertical direction of a screen according to a second embodiment.

FIG. 6 is a cross-sectional view showing a cut state along a horizontal direction of a screen according to a second embodiment.

FIG. 7 is an explanatory diagram schematically illustrating a basic configuration of an image display device.

FIG. 8 is a perspective view showing an overall configuration of a screen according to a first conventional example.

FIG. 9 is a cross-sectional view showing a cutting state along a horizontal direction of the screen according to the first conventional example.

FIG. 10 is a perspective view showing an overall configuration of a screen according to a second conventional example.

FIG. 11 is a cross-sectional view showing a cut state along a horizontal direction of a screen according to a second conventional example.

[Description of Signs] 5 Fresnel lens sheet (light collimating member) 6 Light diffusing member (lenticular lens sheet) 7 Vertical light diffusing member 71 Lenticular lens 72 Black stripe 8 Horizontal light diffusing member 81 Refractive lenticular lens 82 Reflective lenticular lens

Claims (3)

[Claims] A light-parallelizing member that converts the projection light into substantially parallel light; and a light-diffusing member that diffuses the substantially parallel light in a vertical direction and a horizontal direction. A lenticular lens having a vertical direction is formed on a light incident surface, a black stripe having a horizontal direction as a longitudinal direction is provided at a light non-transmissive portion located near a focal point of the lenticular lens, and a lenticular having a vertical direction as a longitudinal direction. A rear projection screen, wherein a lens is formed on a light exit surface. 2. A light collimating member for converting projection light into substantially parallel light, a horizontal light diffusing member for mainly diffusing substantially parallel light in a horizontal direction, and a light diffusing member for diffusing horizontally diffused light mainly in a vertical direction. A vertical light diffusing member, wherein the horizontal light diffusing member has a flat light incident surface and a lenticular lens having a vertical direction as a longitudinal direction formed on the light emitting surface. A lenticular lens having a horizontal direction as a longitudinal direction is formed on a light incident surface, and a black stripe having a horizontal direction as a longitudinal direction is provided at a light non-transmissive portion of a light emitting surface located near a focal point of the lenticular lens. A rear projection screen characterized by the following. 3. A method for manufacturing a light diffusing member provided in a rear projection screen according to claim 1, wherein a lenticular lens having a horizontal direction as a longitudinal direction is formed on one surface, and a thickness of the lenticular lens is reduced. A step of producing a vertical light diffusing member provided with a black stripe at a light non-transmissive portion on the other surface which is substantially equal to the focal length and located near the focal point of the lenticular lens; A lenticular lens is formed, the other surface is a step of producing a horizontal light diffusion member, and the other surface provided with the black stripe of the vertical light diffusion member and the other flat surface of the horizontal light diffusion member are respectively lenticular lenses. Wherein the longitudinal directions are perpendicular to each other, and the optically coupled state is established. The method of manufacturing the material.