JP2000221590A - Back projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a back projection type display device in which an installation space at the time of storing can be reduced. SOLUTION: In the back projection type display device projecting and displaying projected light from a video projecting device 3 from the back surface side of a diffusion screen 5 by reflecting by a reflection mirror 4, a left side housing 21 provided with the reflection mirror 41 and a screen 51 and a right side housing 22 provided with the reflection mirror 42 and the screen 52 are freely tunably attached at the fixed shaft 11 of a base part 1 at which the video projecting device 3 is fixed, and the reflection mirrors 41 and 42 and the screens 51 and 52 are made changeable to a housing position at which they are bent and a used position at which they are opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear projection display device which receives image light from an image projection device on the back side of a screen and emits the image light toward an observer located on the front side of the screen. About.

[0002]

2. Description of the Related Art FIG. 4 is a schematic configuration diagram showing a conventional rear projection display device. This rear projection display device,
It comprises an image projection device 102, a projection lens 103, a reflection mirror 104 and a transmission type diffusion screen 105 arranged in a housing 101. Video projection device 10
Projection image light emitted from the projection lens unit 1
The projection screen 103 is enlarged and projected by the projection mirror 03, reflected by the reflection mirror 104, and incident on the rear side of the transmission type diffusion screen 105. An observer can see an image at a position in front of the diffusion screen 105. This type of rear projection display device has an advantage that it is easy to enlarge the screen as compared with a structure using a cathode ray tube as a screen.

[0003]

However, the above rear projection display device can obtain a large screen by projection display, but the diffusion screen 105 needs a size of an image to be projected. For this reason, even when the device is not used, a space for placing the rear projection display device having a large screen is required, and a large space is required for a storage place.

An object of the present invention is to provide a rear-projection display device capable of reducing the installation space during storage, which has been made to solve the conventional problems described above.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a rear projection type display apparatus for projecting and displaying from a back side of a screen by reflecting projection light from an image projection apparatus with a reflection mirror.
At least the reflection mirror and the screen are foldably attached around a vertical axis of a device main body provided with the image projection device, and the reflection mirror and the screen are changed to a folded storage position and an open use position. It is characterized in that it is configured to be possible.

It is preferable that the reflection mirror and the screen are configured to be symmetrically bent from the center of the main body.

As described above, since at least the reflection mirror and the screen are foldably mounted, the reflection mirror and the screen can be stored in a folded state, so that the installation space at the time of storage can be reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The rear projection display device of the present invention is suitable for use as a communication display device and an information display terminal in public institutions and companies.

FIG. 1 is a perspective view showing a use state of the rear projection type display apparatus of the present invention, FIG. 2 is a perspective view showing a stored state,
FIG. 3 is a top view showing the transition from the use state to the housed state.

As shown in the figure, a rear projection display apparatus according to this embodiment has a housing 2 which can be bent into two in a fan shape on a base 1 of an apparatus main body, and an image fixed to the base 1. A projection device 3, a total reflection mirror 4 that totally reflects the image light projected from the image projection device 3, and a transmission that receives the image light reflected by the total reflection mirror 4 from the back side and diffuses and emits it to the front side. And a diffusion screen 5 of a mold type. As will be described later, the total reflection mirror 4 and the diffusion screen 5 are configured so as to be able to be bent into two with respect to the base 1 together with the housing 2.

The housing 2 includes a left housing 21 and a right housing 2.
2 and a vertical fixed shaft 1 provided on the base 1.
1 and rotatably attached around the fixed shaft 11. The left screen part 51 and the left reflection mirror 41 are fixed to the left housing 21, and the right screen part 52 and the right reflection mirror 42 are fixed to the right housing 22.

The image projection device 3 includes a liquid crystal display panel, a light source such as a halogen lamp or a metal halide lamp, and a projection lens. Then, on / off of the liquid crystal display panel is controlled by a video display control unit (not shown), and video light modulated by the liquid crystal display panel is emitted from the projection lens toward the total reflection mirror 4.

The housing 2 is provided with a lock mechanism (not shown) so that it can be held in the use state shown in FIG. 1 and the housed state shown in FIG. 2, respectively.

When the housing 2 is locked in the use state shown in FIG. 1, the opposing sides of the reflection mirrors 41 and 42 come into close contact with each other to form one total reflection mirror 4. Also, at this time, the sides of the screens 51 and 52 facing each other are in close contact with each other to form one diffusion screen 5.

In this state, the image light projected from the image projection device 3 is guided to the diffusion screen 5 by the above-mentioned total reflection mirror 4.

As shown in FIG. 3, the transition from the use state to the storage state is performed by releasing the lock mechanism in the state shown in FIG. 3 (a) and moving the housings 21 and 22 around the fixed shaft 11 as shown in FIG. (See the same figure (b)). The screens 51, 52 of the housings 21, 22 respectively
The two housings 21 and 22 are fixed by the lock mechanism in a state in which the back surfaces on the opposite side are in contact with each other (see FIG. 3C). Thus, the storage state shown in FIG. 2 is changed from the use state shown in FIG.

As described above, the diffusion screen 5 and the total reflection mirror 4 are stored in a state of being folded in half.
For this reason, the space for storing can be reduced.

The transition from the housed state to the used state may be performed by turning the housings 21 and 22 in the direction in which the housings 21 and 22 are expanded in the opposite manner to the state shown in FIG.

In the above-described embodiment, the housings 21 and 22 on the back side of the screens 51 and 52 are configured to be in contact with each other, but the housings can be stored in the direction in which the surfaces of the screens 51 and 52 are in contact with each other. The housings 21 and 22 may be attached to the base unit 1.

[0020]

As described above, according to the present invention, since the screen and the reflecting mirror are configured to be foldable, the installation space at the time of storage can be greatly reduced, and the storage can be facilitated.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a use state of a rear projection display device of the present invention.

FIG. 2 is a perspective view showing a stored state of the rear projection display device of the present invention.

FIG. 3 is a top view showing a transition from a use state to a housed state of the rear projection display device of the present invention.

FIG. 4 is a schematic sectional view of a conventional rear projection display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base part 11 Fixed axis 2 Housing 21 Left housing 22 Right housing 3 Video projection device 4 Total reflection mirror 41 Left reflection mirror 42 Right reflection mirror 5 Diffusing screen 51 Left screen 52 Right screen

Claims (2)

[Claims] 1. A rear projection display device that reflects projection light from an image projection device by a reflection mirror and projects and displays the image from the rear side of a screen, around a vertical axis of a device main body provided with the image projection device. A rear projection display device, wherein at least the reflection mirror and the screen are foldably attached, and the reflection mirror and the screen are configured to be changeable between a folded storage position and an open use position. . 2. The rear projection display device according to claim 1, wherein the reflection mirror and the screen are bent symmetrically from a central portion of the device main body.