JPH06222382A - Liquid crystal rear projector device - Google Patents

Abstract

PURPOSE:To obtain a high-definition and high-luminance liquid crystal rear projector device by combining plural liquid crystal projectors. CONSTITUTION:In the liquid crystal rear projector device constituted by providing the liquid crystal projectors P including a light source provided with a reflector, a liquid crystal panel on which a prescribed video is displayed and a projection lens enlarging and projecting the video on the liquid crystal panel by light from the light source, a transmission type screen 5a and a reflecting mirror 6 reflecting the video projected from the projector P toward the screen 5a; the plural projectors P (P1 and P2) are provided. Then, one video is divided as many as the number of projectors, displayed on the liquid crystal panels of the projectors P1 and P2 and reproduced on the screen 5a as one video.

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 liquid crystal rear projector device, and more particularly to a liquid crystal rear projector device using a plurality of liquid crystal projectors in combination.

[0002]

2. Description of the Related Art FIG. 3 illustrates a general conceptual view of a liquid crystal projector. According to this, the liquid crystal projector P is composed of a light source 1, a liquid crystal panel 2, a projection lens 3, and a condenser lens 4 for condensing light from the light source 1 onto the projection lens 3.

The light source 1 is generally a parabolic reflector 1.
a and is placed at its focal point. Thereby, the light source 1
A parallel light beam is emitted from the liquid crystal panel 2 toward the liquid crystal panel 2. A video signal is supplied to the liquid crystal panel 2 via a liquid crystal driver circuit (not shown), and a predetermined video is displayed on the liquid crystal panel 2.

Therefore, when the light from the light source 1 passes through the liquid crystal panel 2, the image is enlarged and projected on the screen 5 through the projection lens 3. The light source 1
The condenser lens 4 and the condenser lens 4 are arranged so that their optical axes coincide with each other so as to illuminate the liquid crystal panel 2 with good balance.

FIG. 4 is a side view of a rear projection type liquid crystal rear projector device in which the liquid crystal projector P is combined with a reflection mirror 6 and a transmissive screen 5.

[0006]

This liquid crystal rear projector device is evaluated in that the device itself can be downsized, but has a problem that the brightness is insufficient. This problem of insufficient brightness becomes more noticeable as the screen becomes larger. Further, as a problem of the liquid crystal panel, there is also a problem of insufficient resolution due to the insufficient number of pixels.

On the other hand, in order to increase the screen size, as shown in FIG. 5, conventionally, for example, two independent liquid crystal rear projectors P1 and P2 are combined, but the joint portion of the screen and the image are displayed. The decrease in the brightness at the joint is a problem. It should be noted that this decrease in brightness is due to the illuminance distribution of the illumination system and the peripheral light amount ratio of the projection lens.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and its structural features are a light source having a reflector, a liquid crystal panel for displaying a predetermined image, and light from the light source. And a liquid crystal projector including a projection lens for enlarging and projecting an image on the liquid crystal panel, a transmissive screen, and a reflection mirror for reflecting an image projected from the liquid crystal projector toward the transmissive screen. In the liquid crystal rear projector device, a plurality of the liquid crystal projectors are provided, and one image is divided into the number of pieces and displayed on the liquid crystal panel of each liquid crystal projector, and reproduced as one image on the transmissive screen. There is something I did.

In this case, it is preferable that the condenser lens incorporated in the illumination system including the light source can be positionally adjusted in the direction orthogonal to the optical axis thereof.

[0010]

According to the above construction, one image is divided and displayed on the liquid crystal panel of each projector, and is reproduced on the screen as one original image. Here, if the screens have the same size, when a plurality of projectors are used, the brightness and the number of pixels are twice as many as the number of projectors used.

In addition, since the display size per projector is small, the projection distance becomes short because of the device size.
The depth dimension of the device is shortened. On the other hand, the lowering of the brightness at the joint of the images can be improved by adjusting the position of the condenser lens in the direction orthogonal to the optical axis thereof.

[0012]

Embodiments of the present invention will be described below.
FIG. 1 shows an example of a rear projection type liquid crystal rear projector device using two liquid crystal projectors P1 and P2. Note that each liquid crystal projector P has the same configuration as the liquid crystal projector P of FIG. 3 described above,
Therefore, the same reference numerals are used for the reference numerals.

According to this embodiment, the liquid crystal projector P
An image signal obtained by dividing one image into two is supplied to each of the liquid crystal panels 2 and 2 of 1 and P2 through a liquid crystal driver circuit (not shown). As a result, an image divided in half is displayed on each liquid crystal panel 2 and 2, and the divided image is reflected from each of the liquid crystal projectors P1 and P2.
It is projected on the transmissive screen 5a via 6 and reproduced as one original image.

From this figure, it will be understood that the depth dimension will be shorter if the screen size is the same. The screen 5a is a lenticular lens + Fresnel lens, and the Fresnel lens is preferably a single-structure Fresnel lens.

FIG. 2 is a conceptual diagram of an optical system of the liquid crystal rear projector device shown in FIG. 1. In this example, the condenser lenses 4 and 4 of the liquid crystal projectors P1 and P2 are arranged in a direction orthogonal to the optical axis thereof. The position can be adjusted.

That is, by moving the condenser lens 4, it is possible to move the brightness distribution on the screen 5a and adjust its brightness so that an image with a bright center is obtained. Instead of this, the light sources 1 and 1 may be moved relatively. In this case, the screen 5a has a single Fresnel lens structure.

[0017]

As described above, according to the present invention, a liquid crystal rear projector device is provided with a plurality of liquid crystal projectors, and one image is divided into the number of images and displayed on the liquid crystal panel of each liquid crystal projector. Since a single image is reproduced on the transmissive screen, a high-definition and high-luminance image can be reproduced. In addition, it is possible to display a high-quality image in which the brightness of the joint is not significantly reduced.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a liquid crystal rear projector device according to the present invention.

FIG. 2 is a conceptual diagram showing an optical system of the same example.

FIG. 3 is a schematic diagram schematically showing a general configuration of a liquid crystal projector.

FIG. 4 is a side view showing a conventional liquid crystal rear projector device.

FIG. 5 is a conceptual diagram showing an optical system when two conventional liquid crystal rear projectors are combined.

[Explanation of symbols]

 1 light source 1a reflector 2 liquid crystal panel 3 projection lens 4 condenser lens 5a screen 6 reflection mirror P liquid crystal projector

Claims (2)

[Claims] 1. A liquid crystal projector including a light source having a reflector, a liquid crystal panel on which a predetermined image is displayed, and a projection lens for enlarging and projecting an image on the liquid crystal panel with light from the light source, and a transmissive screen. A liquid crystal rear projector device comprising a reflection mirror for reflecting an image projected from the liquid crystal projector toward the same transmissive screen, wherein a plurality of the liquid crystal projectors are provided, and one image is divided into the number. A liquid crystal rear projector device characterized in that it is displayed on a liquid crystal panel of each liquid crystal projector and reproduced as one image on the transmissive screen. 2. The liquid crystal rear projector device according to claim 1, wherein a condenser lens incorporated in an illumination system including the light source is positionally adjustable in a direction orthogonal to an optical axis.