JPH04135745U - Rear projection multi-screen - Google Patents

Abstract

(57) [Summary] [Purpose] A rear projection multi-screen that can reduce vertical diffusion of transmitted light and increase the amount of light directed forward, allowing for brighter image display.
The purpose is to provide the following information. [Structure] One screen sheet 17A has lenticular lenses 15 formed on its entire surface, and Fresnel lenses 16A to 16D are formed on the back surface of each screen sheet 17A.
The front surfaces of the two divided screen sheets 18A to 18D are respectively joined to form one screen 13.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention uses multiple liquid crystal projection devices, and each liquid crystal projection is transmitted through a transmissive liquid crystal panel. The light source light of the projection device is used as image light, and the image light is expanded onto the screen from the back side. A back panel used in rear-type multi-LCD projection devices that display images by projecting images. This relates to a surface projection type multi-screen.

0002

[Conventional technology]

In recent years, liquid crystal display technology has made remarkable progress, with superior contrast and color reproducibility. With the advent of color LCD panels, color LCD panels were used as image display carriers, and large screen A liquid crystal color projection device that enlarges and projects images onto a screen has been put into practical use. This type of device is The light from the source is converged into approximately parallel light beams using a converging optical system, and then irradiated onto a transmissive color liquid crystal panel. , the transmitted light is enlarged and projected onto a screen via a projection optical system, and the projection equipment The device is usually placed in front of the screen so that the optical axis is perpendicular to the screen surface. be done. Figures 8 and 9 show the arrangement of such a liquid crystal color projection device and screen. Figure 8 is a schematic diagram showing the configuration of the LCD color projection device 1 when it is installed on the floor of the room. , FIG. 9 shows the case where it is used by hanging it from the ceiling. Note that 2 is approximately vertical along the wall surface. This is a screen placed directly on the screen.

0003

[Problem that the idea aims to solve]

By the way, it is possible to perform rear projection using a plurality of conventional liquid crystal color projection devices 1 as described above. When trying to configure a type multi-LCD projection device, the projection that can be obtained with one LCD projection device is If the projection surface is L = 100 inches, the projection distance D must be approximately 350 cm, which is possible. It was not possible to realize a general type rear projection type multi-liquid crystal projection device. In addition, the screen 2 is made of a single flat plate by injection molding acrylic resin. It is formed on the surface, extends vertically over the entire length in the width direction, and is closely spaced in the left and right direction. A lenticular lens (cylindrical lens) consists of many semi-cylindrical protrusions formed by A type of lens with a linear lens formed over the entire surface is generally used. In this configuration, the light incident on the screen is filtered to the left by a lenticular lens. Although the right direction can be controlled, the vertical direction cannot be controlled and is diffused, so the luminous intensity distribution There was a problem in that the light spread too much in the vertical direction, reducing the brightness toward the front.

0004 Therefore, this invention was made in view of the conventional problems as mentioned above. The purpose is to reduce the vertical diffusion of transmitted light and direct it forward. Rear projection that can increase the amount of light and display brighter images. Our objective is to provide a projection-type multi-screen.

[0005]

[Means to solve the problem]

This invention was made to achieve the above object, and the first invention is a single-sided One screen sheet with lenticular lenses formed on the entire surface and a film on one side. This split screen is equipped with a plurality of split screen sheets on which Lenel lenses are formed. A clean sheet is formed on the lenticular lens of the screen sheet. The Fresnel lens is bonded to the surface opposite to the surface with the Fresnel lens side facing up. The second idea is the first screen in which a lenticular lens is formed on the entire surface of one side. It has a projection sheet and multiple divided projection areas, and multiple Fresnel on one side. Lenses are formed for each projection area and have the same size as the first screen sheet. a second screen sheet having a Join the opposite sides of the screen sheet No. 2 from the lens forming surface to each other and bond both sheets together. It is integrated. The third idea is that a lenticular lens is formed on one entire side of the screen sheet. A Fresnel lens is placed on the other side of the sheet for each of the divided projection areas. The front and back sides are integrally formed.

[0006]

[Effect]

In this invention, the Fresnel lens is a lens that comes out from the liquid crystal projection device that enters the screen. The captured image light is made into parallel light beams to increase the luminous intensity distribution in front of the screen.

[0007]

【Example】

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. Figure 1 shows a partially exploded view of an embodiment of the rear projection type multi-screen according to the present invention. Figure 2 is an external perspective view of the rear type four-sided multi-LCD projection device, and Figure 3 is III of Figure 2. 4 is a sectional view taken along the line IV-IV in FIG. 2, and FIG. 5 is an optical sectional view taken along the line IV-IV in FIG. FIG. 1 is a schematic diagram showing the system. In these figures, the rear type four-sided multi-LCD projection device 1 0 has a vertically thin box-shaped housing 11 that is open at the center of the front, and has an opening on the front side. A rear projection type multi-screen 13 is attached to 12.

[0008] The rear projection type multi-screen 13 is made of acrylic resin or the like. If the projection size L is 80 inches, the width is 160 cm, the height is 120 cm, and the center The four projections are divided into four by vertical and horizontal lines that intersect with each other. It has radiation areas 14A to 14D. Also, on the surface of the multi-screen 13, A large number of semicircular columns that extend vertically over the entire length in the vertical direction and are closely spaced in the horizontal direction. A lenticular lens (cylindrical lens) 15 consisting of a protruding body covers the entire surface. On the other hand, Fresnel lenses 16A to 16D are provided on the back side for each projection. It is integrally formed for each region 14A to 14D. Fresnel lens 16A-16D is a transparent beam that is emitted from a liquid crystal projection device 20 and transmitted through a multi-screen 13, which will be described later. It converts hyperimage light into parallel light, and its cross-sectional shape is approximately triangular and is protruded concentrically. It consists of a plurality of annular protrusions, and the angle of inclination of the inner slope of each protrusion is about the center. It is large and gradually becomes smaller as it moves away from the center. Na Oh, the lenticular lens 15 transmits through the multi-screen 13. It focuses the transmitted image light in front of the screen and enhances the light distribution characteristics to the front. .

[0009] When manufacturing the rear projection type multi-screen 13 having the above configuration, As shown in FIG. 1, the lenticular lens 15 is formed on the entire surface and the back surface is flat. Back side of one screen sheet (first screen sheet) 17A with flat surface The projection areas 14A to 14D are divided into parts, each having a flat surface and a flexible back surface. Four divided screen sheets 1 each having flannel lenses 16A to 16D formed thereon. 8A to 18D are bonded and fixed using an optical adhesive. The rear projection type multi-screen 13 manufactured in this way is The front surface of the housing 11 is held at its edge by a frame 19 made of aluminum or the like. It is fitted and fixed into the side opening 12.

0010 Inside the housing 11, there are respectively upper and lower rear portions of the screen. A total of four liquid crystal projection devices 20, two each, correspond to each of the projection areas 14A to 14D. The image light 28 emitted from each liquid crystal projection device 20 is refracted and reflected twice. A set of two sheets to be projected onto the projection areas 14A to 14D corresponding to the liquid crystal projection device. Four sets of reflecting mirrors 22 are arranged. The liquid crystal projection device 20 is shown in FIG. 5, a light source 25 such as a xenon lamp converts the emitted light from the light source 25 into approximately parallel light. The condenser lens 26 transmits the obtained substantially parallel light source light 27 and converts it into image light 2. 8, a transmission type liquid crystal panel 29, magnifying the image light 28 transmitted through the liquid crystal panel 29 It is composed of an L-shaped projection lens 30 and the like for projecting onto a multi-screen 13. The liquid crystal panel 29 has TN mode liquid crystal cells arranged. By changing the voltage applied to the channel according to the television video signal, the LCD panel can be Television images are displayed on the channel 29. The L-type projection lens 30 has two lenses. lenses 31A, 31B, and a mirror 3 disposed between these lenses 31A, 31B. 2, and the lens 31B is the first reflecting mirror 22A of the reflecting mirror 22. They are placed facing forward.

[0011] The reflecting mirror 22 includes the first reflecting mirror 22A and a second reflecting mirror larger than the first reflecting mirror 22A. It is composed of a projection mirror 22B. The first reflecting mirror 22A is the liquid crystal projection device 2 It reflects the image light 28 emitted from 0 backwards diagonally upward or downward; For those corresponding to the projection areas 14A and 14B, as shown in FIG. In front of the crystal projection device 20, at a position above the back of the multi-screen 13, on the rear side. The projector is arranged at an inclined angle and corresponds to the lower two projection areas 14C and 14D. That is, in front of the lower LCD projection device 20 and below the back of the multi-screen 13. It is tilted forward at a predetermined angle. The second reflection mirror 22B has a first reflection mirror 22B. The reflected image light reflected by the mirror 22A is reflected forward diagonally upward or diagonally downward. For those corresponding to the upper two projection areas 14A and 14B, As shown in FIG. 4, it is arranged directly below the upper liquid crystal projection device 20 and tilted backward at a predetermined angle. and for those corresponding to the lower two projection areas 14C and 14D, the lower liquid crystal It is disposed directly above the projection device 20 and inclined forward at a predetermined angle.

0012 Here, each liquid crystal projection device 20 is positioned above and below the rear of the multi-screen 13. When installed, the upper and lower ends of each projection area 14A to 14D of the multi-screen 13 Due to the difference in optical path length between the L-shaped projection lens 30 and the Blurred images occur. Therefore, in this embodiment, such trapezoidal distortion and defocusing are avoided. In order to prevent the loss of liability as much as possible, the earlier application filed by the same applicant (patent application -299857), the liquid crystal panel 29, the L-shaped projection lens 30 and the first The second reflecting mirrors 22A and 22B are each tilted forward or backward at a predetermined angle, The optical path length is being corrected. For details, see the above patent application No. 2-29985. Since it is explained in detail in No. 7, the explanation will be omitted here.

[0013] Thus, in the rear type four-sided multi-LCD projection device 10 having such a configuration, The four liquid crystal projection devices 20 are mounted on the upper back side of the rear projection type multi-screen 13. Reflection mirrors are arranged at the bottom of the screen corresponding to each of the projection areas 14A to 14D, respectively. 22, the projection distance (multi-screen) is refracted and reflected twice. The straight line distance between the lean-to 13 and the LCD projection device 20 can be significantly shortened. Multi-screen 13 and LCD projection device in housing 11 with a distance of only 50 cm 20 can be incorporated. Therefore, the back type is thin and compact and has excellent flexibility. A four-sided multi-screen LCD projection device can be provided. In addition, rear projection multi- The screen 13 is a screen on which the lenticular lenses 15 are formed on the entire surface. Lean sheet 17A and four sheets joined to the back of this screen sheet 17A. Consisting of split screen sheets 18A to 18D, each split screen sheet 18 A liquid crystal projection device using Fresnel lenses 16A to 16D provided on the back surfaces of A to 18D. Since the image light 28 from 20 is a parallel ray that is approximately perpendicular to the screen surface, When passing through the multi-screen 13, the amount of transmitted light heading forward increases and It is possible to reduce the amount of light that is diffused in the direction and diagonally downward. Therefore, yo We are able to provide a rear projection multi-screen that provides a brighter image display. Wear. In addition, the rear projection type multi-screen 13 consists of one screen sheet 1 Since split screen sheets 18A to 18D are joined to the back side of 7A, this The joints of the split screen sheets 18A to 18D, that is, the joint surfaces are in front of the screen. It is not visible from the front and has a good appearance from the front.

[0014] FIG. 6 is an exploded perspective view showing another embodiment of the present invention. This example shows the entire surface a first screen sheet 17A on which a lenticular lens 15 is formed; It has four divided projection areas 14A to 14D, and four Fresnel lenses 1 on the back side. The first screen 6A to 16D is formed for each projection area 14A to 14D. A second screen sheet 18 having the same size as the screen sheet 17A is integrated. By joining them together, a rear projection type multi-screen 13 is manufactured. Even in this configuration, the same effect as the multi-screen shown in Figure 1 can be obtained. That's what you get.

[0015] FIG. 7 is a perspective view showing still another embodiment of the present invention. This example uses one screen. The lenticular lens 15 is formed on the entire one side of the lean sheet 17, and the On the other surface, Fresnel lenses 16A to 16D are installed for each of the divided projection areas. The front and back sides are integrated into a multi-screen.

[0016] In addition, in each of the above embodiments, the rear projection type multi-screen 13 has four projections. Although the case where the area is divided into areas 14A to 14D has been explained, the present invention is not specific to this. It can be divided into 2, 6, 8, etc. depending on the projection size. is possible.

[0017]

[Effect of the idea] As explained above, according to the rear projection type multi-screen according to the present invention, the screen Increasing the transmitted image light from the LCD projection device that passes through the screen and goes forward. I can do that. Therefore, you can get a brighter image display and a large rear projection screen. It is suitable for application to projection type multi-screens.

[Brief explanation of drawings]

FIG. 1 is a partially exploded perspective view showing an embodiment of a rear projection type multi-screen according to the present invention.

FIG. 2 is an external perspective view showing an embodiment of a rear type four-sided multi-liquid crystal projection device.

FIG. 3 is a sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2;

FIG. 5 is a schematic diagram showing an optical system of a liquid crystal projection device.

FIG. 6 is an exploded perspective view showing another embodiment of the rear projection type multi-screen.

FIG. 7 is a perspective view showing still another embodiment of the present invention.

FIG. 8 is a projection state diagram when a conventional liquid crystal color projection device is installed on the floor.

FIG. 9 is a projection state diagram when a conventional liquid crystal color projection device is suspended from the ceiling.

[Explanation of symbols]

10 Rear type 4-sided multi-LCD projection device 11 Housing 13 Rear projection multi-screen 14A-14D Projection area 15 Lenticular lens 16A~16D Fresnel lens 17 First screen sheet 18 Second screen sheet 18A~18D split screen sheet

Claims (3)

[Scope of utility model registration request] 1. A screen sheet having a lenticular lens formed on its entire one side, and a plurality of divided screen sheets having a Fresnel lens formed on one side, the divided screen sheet being used as the lenticular lens of the screen sheet. 1. A rear projection type multi-screen, characterized in that the Fresnel lens side is bonded to a surface opposite to the surface on which is formed, with the Fresnel lens side facing up. [Claim 2] A first screen sheet having lenticular lenses formed on the entire one side, and a plurality of divided projection areas, and a plurality of Fresnel lenses formed on one side for each projection area. , a second screen sheet having the same size as the first screen sheet, and the surfaces of the first screen sheet and the second screen sheet opposite to the lens forming surfaces are joined to each other, and both sheets are bonded to each other. A rear-projection multi-screen featuring an integrated system. 3. A rear projection type multi-lens lens, characterized in that a lenticular lens is formed on the entire one side of the screen sheet, and a Fresnel lens is formed on the other side of the sheet for each of a plurality of divided projection areas. screen.