JPH0572635A - Rear projection type screen - Google Patents

Abstract

PURPOSE:To easily manufacture a rear projection type screen at a low cost by laminating long and slender fine members having the incident surface, the emitting surface and the reflecting surface of light at a prescribed angle and mutually adhering or holding them with transparent members, and thereby forming the screen. CONSTITUTION:This rear projection type screen is formed by laminating the long and slender fine members 1 whose cross sections are rectangular and which are provided with the incident surface 6, the emitting surface 7 and the reflecting surface 5 of the light by being obliquely inclined and interposing them by the transparent members 2-4 from the front and back and the top and bottom parts. In such a case, it is good that the fine members 1 are mutually made to adhere. In the case that the reflection of projected light on an air layer between the fine members 1 is not expected because of the adhesion, the reflecting surface 5 is previously formed by metal plating. Then, the projected light 8 made incident on the screen from an oblique direction is firstly transmitted through the rear transparent member 2, made incident from the light incident surface 6 of the fine member 1 and reflected on the reflecting surface 5. Thereafter, it is emitted from the light emitting surface 7, transmitted through the front transparent member 3 on which a lenticular lens is formed and outputted to an observer side from the front surface of the screen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen used for a display device for magnifying and projecting a video image, a computer image or the like from the rear.

[0002]

2. Description of the Related Art Conventionally, there is known a magnifying projection display device which magnifies and projects a display image of a CRT or a liquid crystal on a screen.

Recently, an oblique rear projection type display device, which aims to make the depth of the rear projection type display device very thin, enlarges a display image of a CRT or a liquid crystal or the like diagonally on the screen to show a large screen. Is proposed. The screen used for this is, as seen in JP-A-61-28041, the projection light emitted from the projection lens is made incident from the oblique rear direction of the screen and is totally reflected by a minute prism provided on the entire surface of the screen. And is emitted to the observer side.

[0004]

To make the above screen, a large mold having the same size as the screen is required. To make this mold, a very precise machining process was required, and it took a very long time. Therefore, the mold was very expensive. In addition, there is a problem that the tip of a saw-toothed mold for forming the minute prism is immediately rounded, and scratches on the mold are transferred to the product to impair the performance.

The object of the present invention is not to require a large mold,
An object of the present invention is to provide a rear projection screen that can be produced in a short period of time and is inexpensive and easy to produce.

[0006]

A rear projection screen is formed by obliquely stacking elongated fine members each having a light incident surface, a light emitting surface, and a reflecting surface. At this time, the minute members may be adhered to each other to form a screen, or the front and rear and upper and lower sides of the laminated minute members may be sandwiched by transparent members.

To widen the viewing angle of the screen, a lenticular lens may be formed on the observation side of the minute member. Alternatively, a lenticular lens may be formed on the observation side transparent member. If a cylindrical Fresnel lens is formed on the projection light incident surface of the minute member or a cylindrical Fresnel lens is formed on the projection light incident side transparent member, the periphery of the image projected on the screen can be brightened.

[0008]

【Example】

(Embodiment 1) FIG. 1 is an embodiment of the present invention, FIG. 2 is an embodiment of a rear projection type display device using the rear projection screen according to the present invention, and FIG. 3 is a screen of this embodiment. It is a horizontal sectional view.

As shown in FIG. 1, a long and slender minute member 1 having a rectangular cross section and having a light incident surface 6, a light emitting surface 7 and a reflecting surface 5 is laminated at an angle, and the transparent member 2 is formed. 3,
At 4, the rear projection screen is formed by sandwiching it from the front and back and the top and bottom. At this time, the minute members 1 may be adhered to each other. When the reflection of the projected light by the air layer between the minute members 1 cannot be expected due to the adhesion, the reflecting surface 5 is formed in advance by plating or the like. In order to widen the horizontal viewing angle of the screen, a lenticular lens 14 is formed in the vertical direction on the front transparent member 3 as shown in FIG.

As shown in FIG. 2, the projection light 8 emitted from the projection optical unit 9 including the display body is the first reflection mirror 1.
After being reflected by 0 and reflected by the second reflecting mirror 11, the light is incident on the screen 12 from an oblique direction. Screen 12
As shown in FIG. 1, the projection light 8 incident on the oblique direction first passes through the rear transparent member 2, enters from the light incident surface 6 of the minute member 1, and is reflected by the reflecting surface 5. After that, the light is emitted from the light emitting surface 7, transmitted through the front transparent member 3 on which the lenticular lens 14 is formed, and emitted from the front surface of the screen 12 to the observer side.

Here, in the lenticular lens portion 14,
By forming the black stripes 15, the contrast of the projected image can be improved.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.

In this embodiment, as in the case of the first embodiment, the minute members 1 are laminated and the front and rear and the upper and lower sides are sandwiched by the transparent members 2, 3 and 4 to form a rear projection screen. Here, as shown in the horizontal sectional view of FIG. 4, a cylindrical Fresnel lens 16 is formed on the rear transparent member 2 on the side where light is incident,
Make the area around the image projected on the screen bright.

Similarly to the first embodiment, the projection light 8 incident from an oblique direction first is refracted and transmitted through the cylindrical Fresnel lens 16 of the rear transparent member 2, passes through the minute member 1, and the lenticular lens 14 is formed. The light passes through the front transparent member 3 and is emitted to the observer side.

(Embodiment 3) FIG. 5 shows a third embodiment of the present invention, and FIG. 6 is a view of the minute member 17 forming the screen of this embodiment as seen obliquely from above.

As shown in FIG. 5, elongated minute members 17 each having a trapezoidal cross section and having a light incident surface 6, a light emitting surface 7 and a reflecting surface 5 are laminated in an inclined state and are adhered to each other. , Forming a rear projection screen. Moreover, in order to widen the horizontal viewing angle of the screen, as shown in FIG.
A lenticular lens 18 is formed vertically on the light emitting surface 7 of the optical element 7, and a cylindrical Fresnel lens 16 is formed vertically on the light incident surface 6 of the minute member 17.

Similar to the first embodiment, the projection light 8 incident from an oblique direction enters from the light incident surface 6 of the minute member 17 on which the cylindrical Fresnel lens 16 is formed, and is reflected by the reflecting surface 5. Then, the light is emitted from the light emitting surface 7 on which the lenticular lens 18 is formed.

[0018]

As described above, elongated rear members having a light incident surface, a light emitting surface, and a reflecting surface are laminated at a predetermined angle, and they are adhered to each other or sandwiched by transparent members to form a rear projection screen. As a result, since a mold is not required to create the screen, it is possible to provide a rear projection screen that can be created in a short period of time and that is inexpensive and easy to create.

If a lenticular lens is formed on the observation side of the minute member or a lenticular lens is formed on the observation side transparent member, the viewing angle of the screen can be widened. Further, by forming a cylindrical Fresnel lens on the projected light incident side of the minute member or by forming a cylindrical Fresnel lens on the projected light incident side of the transparent member, the periphery of the image projected on the screen can be brightened.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a screen according to a first embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a rear projection type display device using the screen of the present invention.

FIG. 3 is a horizontal sectional view of the screen according to the first embodiment of the present invention.

FIG. 4 is a horizontal sectional view of a screen according to a second embodiment of the present invention.

FIG. 5 is a vertical sectional view of a screen according to a third embodiment of the present invention.

FIG. 6 is a view of a minute member forming a screen according to a third embodiment of the present invention as seen obliquely from above.

[Explanation of symbols]

 1, 17 Micro member 2 Rear transparent member 3 Front transparent member 4 Upper and lower transparent member 5 Reflection surface 6 Incident surface 7 Exit surface 8 Projected light 9 Projection optical unit 10 First reflection mirror 11 Second reflection mirror 12 Screen 13 Cabinet 14a Lenticular lens 14b Lenticular lens 15 Black stripe 16 Cylindrical Fresnel lens 18 Lenticular lens

Claims (6)

[Claims] 1. A rear projection screen, characterized in that elongated minute members (1, 17) having a light incident surface, a light emitting surface and a reflecting surface are laminated at a predetermined angle. 2. The rear projection screen according to claim 1, wherein the minute members (1, 17) are sandwiched by transparent members (2, 3, 4). 3. The rear projection screen according to claim 1, wherein a lenticular lens (14) is formed on the transparent member (3). 4. The rear projection screen according to claim 1, wherein a cylindrical Fresnel lens (16) is formed on the transparent member (2). 5. The rear projection screen according to claim 1, wherein a lenticular lens (18) is formed on a light emitting surface of the minute member (1, 17). 6. The rear projection screen according to claim 1, wherein a cylindrical Fresnel lens (16) is formed on a light incident surface of the minute member (1, 17).