JPH06109992A - Large-sized video display unit - Google Patents

Abstract

PURPOSE:To obtain a large-sized video display unit which projects a large screen video having high brightness on a screen by using plural laser projectors. CONSTITUTION:The unit possesses plural laser beam projectors 13a and 13b, a video input device 11 which outputs a video signal and a video signal distributor 12 that generates the video signals mutually synchronizing based on the video signals (a) and (b) outputted by the video input device and respectively supplies them to respective laser beam projectors. Then respective laser beam projectors 13a and 13b possess a scanning means superposing a laser beam position being projected on the screen 14 by the plural laser beam projectors at nearly the same point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized image display device capable of projecting a large-screen image on a screen using a laser.

[0002]

2. Description of the Related Art A screen with a large screen and high brightness is screened.
Every year, it is required to draw a picture. As one of them, there is known a liquid crystal projector in which a large screen is projected on a screen by a liquid crystal type video projector.

[0003]

In order to increase the brightness of an image projected on a screen by such a liquid crystal projector, a plurality of liquid crystal projectors are used to superimpose pixels on the screen. It is possible.

However, if there is a step in the screen, the focus at that position will not be in focus, so a plurality of liquid crystal projectors will be used to overlap the pixels on the screen and the brightness of the image will be improved. Was difficult to increase.

The present invention has been made in view of the above points, and an object thereof is to use a plurality of laser projectors.
It is an object of the present invention to provide a large-sized image display device capable of projecting a large-screen image with high brightness on a screen.

[0006]

A large-sized image display device according to a first aspect of the present invention comprises a plurality of laser beam projectors, an image input device for outputting an image signal, and an image signal output from the image input device. And a video signal distributor which supplies video signals to the respective laser beam projectors in synchronization with each other, and each laser beam projector screens from the plurality of laser beam projectors. A scanning means is provided for superimposing the laser beam positions projected on the lens at substantially the same point. The scanning means of the large-sized image display device according to the second aspect is characterized in that the laser beam is scanned from the same position on the screen in the same direction. The scanning means of the large-sized image display apparatus according to the third aspect is characterized in that the laser beam is scanned from different positions on the screen in different directions.

[0007]

According to the present invention, each laser projector superimposes each laser beam on substantially the same point on the screen based on the mutually synchronized video signals supplied from the video signal distributor. Is scanning. In claim 2, the scanning means of the large-sized image display device acts so as to scan the laser beam from the same position on the screen in the same direction. In the second aspect, the scanning means of the large-sized image display device acts so as to scan the laser beam from different positions on the screen in different directions.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A large image display device according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a large-sized image display device, FIG. 2 is a diagram showing a scanning method of a laser beam, and FIG. 3 is a diagram showing how laser beams overlap.

In FIG. 1, reference numeral 11 is a video input device such as a video camera or a video deck. The video signal output from the video input device 11 is a video signal distributor 12
Entered in.

The video signal distributor 12 distributes the input video signal, for example, to generate two video signals a and b synchronized with each other. The video signals are respectively supplied to the first and second laser beam projectors 13a and 1a.
3b is output.

The first and second laser beam projectors 13a and 13b are provided with two laser beams on the screen 14.
The scanning is performed so that the frames a1 and a2 substantially overlap. In addition,
The laser beams a1 and a2 are composed of R, G and B beams, respectively.

As shown in FIG. 2, the first and second laser beam projectors 13a and 13b are laser beam a.
1, a2 are simultaneously scanned from the upper left of the screen 14 toward the right direction, and a scanning means for causing the laser beams a1 and a2 to produce bright spots b1 and b2 at substantially the same position of the screen 14 is provided. is doing.

Next, the operation of the embodiment of the present invention constructed as above will be described. The video signal output from the video input device 11 is input to the video signal distributor 12,
The video signal distributor 12 distributes the input video signal into two video signals a and b which are synchronized with each other to divide the video signal into first and second video signals.
Output to the laser beam projectors 13a and 13b. Then, by the scanning means provided in the first and second laser beam projectors 13a and 13b, as shown in FIG.
The laser beams a1 and a2 are screened as shown in FIG.
Simultaneously scanning from the upper left to the right direction, bright points b1 and b2 are generated at almost the same position of the screen 14 by the laser beams a1 and a2.

By the way, the bright spot b on the screen 14
The overlap of 1 and b2 is 2 on the screen 14, for example.
A state where the laser beams a1 and a2 of the book are just overlapped [Fig. 3 (A)] and a part thereof is overlapped [Fig. 3 (B)]
Then, there is a case where the state is separated by a certain distance d [FIG. 3 (C)]. In order to improve the brightness on the screen 14, the larger the overlapping portion is, the higher the ratio of the brightness is improved. However, as shown in FIG. Is about 3 minutes (approx.
When the distance is 0 m, the distance d is about 9 mm. ), It is experimentally found that if the two bright points b1 and b2 have the same luminance, the observer can see the luminance as about 1.4 times.

This means that the bright points b1 and b2 do not necessarily have to completely overlap each other as long as the image quality is not deteriorated (for example, the range where the images are not blurred).

Although the first and second laser beam projectors 13a and 13b have the scanning means described with reference to FIG. 2, they have the scanning means as described with reference to FIG. You can have it. As shown in FIG. 4, this scanning means scans the laser beam a1 from the upper left of the screen 14 toward the right direction and scans the laser beam a2.
This is a scanning method in which scanning is performed from the lower right side of the window 14 toward the left side. Even with such a scanning method, the screen 14
The upper two bright spots can be located at substantially the same position, and the brightness can be increased.

In the above embodiment, the case where two laser beam projectors 13a and 13b are used has been described, but the brightness can be further increased by using three or more laser beam projectors. It is possible. 5 is 5
An example of using the laser beam projectors 21 to 25 is shown. Thus, the greater the number of laser beam projectors used, the higher the brightness obtained on the screen 14. In this case, the range in which the projectors 21 to 25 are arranged with respect to the screen 14 is considerably wide, and the normal line of the screen 14 and the projectors 21 to 2 are arranged.
There is a difference in the angle (φ) formed by the optical axis of 5 and the distance between the screen 14 and the projectors 21 to 25 (l1 and l
Even if it is not equal to 2, the deviation of the bright spot position of the laser beam is small and correction is possible. Further, the change in the size of the bright spot due to the difference in the distance is small, and the image quality is not deteriorated.

[0018]

As described in detail above, according to the present invention, there is provided a large-sized image display device capable of projecting a large-intensity large-screen image on a screen by using a plurality of laser projectors. Can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram of a large-sized image display device according to an embodiment of the present invention.

FIG. 2 is a view showing a scanning method of the laser beam.

FIG. 3 is a view showing an overlapping condition of the laser beam.

FIG. 4 is a diagram showing another scanning method of the laser beam.

FIG. 5 is a diagram showing a configuration of a large-sized image display device using a laser beam projector.

[Explanation of symbols]

11 ... video input device, 12 ... video signal distributor, 13a,
13b ... laser beam projector, 14 ... screen
N.

Claims (3)

[Claims] 1. A plurality of laser beam projectors, a video input device for outputting a video signal, and video signals synchronized with each other are generated based on the video signals output from the video input device. The laser beam projectors are respectively provided to the beam projectors, and each laser beam projector has almost the same laser beam position projected on the screen from the plurality of laser beam projectors. A large-sized image display device comprising scanning means for superimposing at the same point. 2. The scanning means screens a laser beam.
The large-sized image display device according to claim 1, wherein scanning is performed in the same direction from the same position on the screen. 3. The scanning means screens a laser beam.
2. A large image display device according to claim 1, wherein scanning is performed in different directions from different positions on the screen.