JP4208318B2 - Rear projection display - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rear projection display device that receives image light from an image projection device on the back side of a screen and emits image light toward an observer located on the front side of the screen.
[0002]
[Prior art]
FIG. 4 is a schematic configuration diagram showing a conventional rear projection display device. The rear projection display device includes an image projection device 102, a projection lens 103, a reflection mirror 104, and a transmissive diffusion screen 105 disposed in a housing 101. Projection image light emitted from the image projection device 102 is enlarged and projected by the projection lens unit 103, reflected by the reflection mirror 104, and incident on the back side of the transmissive diffusion screen 105. An observer can view an image at a front position 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]
[Problems to be solved by the invention]
However, although the above-described rear projection display device can obtain a large screen by projection display, the diffusing screen 105 requires the size of the projected image. For this reason, a space for placing a rear projection display device having a large screen is required even when the device is not used, and a large space is required for the storage location.
[0004]
An object of the present invention is to provide a rear projection display device that is made to solve the above-described conventional problems and can reduce an installation space during storage.
[0005]
[Means for Solving the Problems]
According to the present invention, in a rear projection display device that projects projection light from a video projection device by a reflection mirror and displays the projection from the rear side of the screen, the reflection mirror and the screen are separated into two and separated into two. Each of the two housings that are disposed in the housing is separated from each other and is pivotally attached to a vertical fixed shaft provided on a base portion to which the image projection device is fixed. Each of the casings is rotated to a position where the opposite sides of the reflection mirror and the screen are in close contact with each other to form one reflection mirror and screen. In the housed state, the reflection mirror and the screen are separated into two. Each housing is configured to rotate to a position.
[0006]
The reflection mirror and the screen may be configured to be separated symmetrically.
[0007]
As described above, since at least the reflection mirror and the screen are separably attached, they can be stored in a separated state, so that the installation space during storage can be reduced.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3. 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.
[0009]
FIG. 1 is a perspective view showing a usage state of a rear projection display device of the present invention, FIG. 2 is a perspective view showing a storage state, and FIG. 3 is a top view showing a transition from the usage state to the storage state.
[0010]
As shown in the figure, a rear projection display device according to this embodiment includes a housing 2 that can be bent in a fan shape at a base portion 1 of an apparatus body, and an image projection device 3 that is fixed to the base portion 1. A total reflection mirror 4 that totally reflects the image light projected from the image projection device 3, and a transmission type diffusion 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 screen 5. As will be described later, the total reflection mirror 4 and the diffusing screen 5 are configured to be foldable into two in a fan shape with respect to the base portion 1 together with the housing 2.
[0011]
The housing 2 is composed of a left housing 21 and a right housing 22, and is rotatably attached to a vertical fixed shaft 11 provided on the base portion 1, and is attached to be openable and closable around the fixed shaft 11. Yes. A left screen 51 and a left reflecting mirror 41 are fixed to the left casing 21, and a right screen 52 and a right reflecting mirror 42 are fixed to the right casing 22.
[0012]
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.
[0013]
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 storage state shown in FIG.
[0014]
When the housing 2 is locked in the use state shown in FIG. 1, the opposing sides of the reflection mirrors 41 and 42 are brought into close contact with each other to form one total reflection mirror 4. At this time, the opposite sides of the screens 51 and 52 are in close contact with each other to form a single diffusion screen 5.
[0015]
In this state, the image light projected from the image projection device 3 is guided to the diffusion screen 5 by the total reflection mirror 4.
[0016]
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. Direction) (see FIG. 5B). Then, both the casings 21 and 22 are fixed by a lock mechanism in a state where the rear surfaces of the casings 21 and 22 on the opposite sides of the screens 51 and 52 are in contact (see FIG. 10C). In this manner, the use state shown in FIG. 1 is changed to the storage state shown in FIG.
[0017]
In this manner, the diffusing screen 5 and the total reflection mirror 4 are folded in half, and the storage state is obtained. For this reason, the space to store can be reduced.
[0018]
In order to shift from the housed state to the used state, the housings 21 and 22 may be rotated in the direction to expand in the opposite manner to the state shown in FIG.
[0019]
In the above-described embodiment, the storage state is configured such that the casings 21 and 22 on the back side of the screens 51 and 52 are in contact with each other, but the casing 21 is stored so that the screens 51 and 52 can be stored in the contact direction. , 22 may be attached to the base portion 1.
[0020]
【The invention's effect】
As described above, according to the present invention, since the screen and the reflection mirror are configured to be separable, the installation space during storage can be greatly reduced, and storage is facilitated.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a usage state of a rear projection display device of the present invention.
FIG. 2 is a perspective view showing a housed state of the rear projection display device of the present invention.
FIG. 3 is a top view showing a transition from the usage state to the storage state of the rear projection display device of the present invention.
FIG. 4 is a schematic cross-sectional view of a conventional rear projection display device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base part 11 Fixed shaft 2 Housing 21 Left housing 22 Right housing 3 Image projection apparatus 4 Total reflection mirror 41 Left reflection mirror 42 Right reflection mirror 5 Diffusion screen 51 Left screen 52 Right screen

Claims (2)

In a rear projection display device in which projection light is reflected by a reflection mirror from a video projection device and projected and displayed from the back side of the screen, the reflection mirror and the screen are separated into two and in a housing separated into two Each of the housings arranged and separated into two is rotatably attached to a vertical fixed shaft provided on a base portion to which the image projection apparatus is fixed, and is separated into two in use. Each housing rotates to a position where the opposite sides of the reflection mirror and the screen are in close contact with each other to form one reflection mirror and a screen. In the stored state, each reflection mirror and the screen are separated into two positions. A rear projection display device characterized in that a housing is configured to rotate . The rear projection display device according to claim 1, wherein the reflection mirror and the screen are configured to be symmetrically separated .

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