JPH07191632A - Video display device - Google Patents

Abstract

PURPOSE:To provide the video display device which can display character information and a natural image and provides effective visual representation without lowering the resolution of the character information. CONSTITUTION:A liquid crystal panel constituted by sticking a color filter of a single plate is used as one of two liquid crystal panels and a monochromatic liquid crystal panel of a single plate is used as the other; and a natural image of a copy, an illustration, etc., and a text image (character image) of characters or a document are displayed on the different liquid crystal panels and then both the panel display images are put optically together. Namely, the light from a light source unit 8 after being transmitted through the black- and-white liquid crystal panel 5 projects a display image of the black-and-white liquid crystal panel 5 on a screen 15. Similarly, the light from a light source unit 13 after being passed through the color liquid crystal panel 10 projects the display image of the color liquid crystal panel 10 on the screen 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video display device for displaying a natural image and character information.

[0002]

2. Description of the Related Art Conventionally, as a projection type image display device using a liquid crystal panel, a three-plate type and a single-plate type are known.

In the three-panel system, for example, R is provided on three liquid crystal panels.
(Red), G (green), B (blue) light of each color is transmitted,
An image obtained by synthesizing the transmitted light is projected on a screen, and the three liquid crystal panels are driven by image signals of R, G, and B colors.

In the single plate system, for example, R, G and B stripe filters are laminated on a single liquid crystal panel, white light is transmitted through this panel, and a color image is projected on a screen. is there.

[0005]

However, in the conventional example as described above, although the three-panel system has high image quality, there is a drawback that it is expensive because three liquid crystal panels are used. In the single plate method, for example, when displaying characters, the resolution is insufficient.

For this reason, there has been no information display device suitable for displaying the natural image information and the character information corresponding to the multimedia which has been attracting attention in recent years in a separated manner.

The present invention has been made in view of the above points, and an object thereof is to display character information and a natural image without lowering the resolution of the character information and to provide an effective visual expression. An object is to provide a video display device capable of performing the above.

[0008]

In order to achieve the above object, the present invention comprises a plurality of image display means and a synthesizing means for optically synthesizing a plurality of display images obtained by the image display means. A video display device, wherein at least one video display means of the video display means displays a color video, and at least one video display means other than the video display means for displaying the color video is a monochromatic video. Is displayed.

Further, according to the present invention, a color liquid crystal panel in which a single-plate color filter is laminated, a single-plate monochrome liquid crystal panel, and an image signal of a natural image are supplied to the color liquid crystal panel, and a text is displayed on the monochrome liquid crystal panel. A signal processing means for supplying an image signal of an image; and an illumination optical system for irradiating the display image of the color liquid crystal panel and the display image of the monochrome liquid crystal panel to display a composite image on the screen. Characterize.

Further, in the present invention, the illumination optical system preferably includes, instead of the illumination optical system, a half mirror for synthesizing a transmitted image of a display image of the color liquid crystal panel and a transmitted image of a display image of the monochrome liquid crystal panel. It can be characterized by having a system and an eyepiece lens for monitoring an image passing through the half mirror.

Further, in the present invention, preferably, the signal processing means extracts a character from the image signal of the natural image and adds the extracted character to the image signal of the text image, and the text image. Means for determining the character area of the image signal and removing the determined area of the character area from the image signal of the natural image.

[0012]

In the present invention, two liquid crystal panels are used, one of which is a single-plate laminated color filter, and the other of which is a single-plate monochrome liquid crystal panel. And a text image of a character and a sentence (character image) are displayed on different liquid crystal panels, and then the panel display images of both are optically combined. As a result, according to the present invention, the quality of the character information can be maintained and the natural image information can be displayed at a relatively low cost. Further, by processing the information signal for driving the two liquid crystal panels according to the input information signal, it is possible to display the character information and the natural image information separately.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings.

1 and 2 show the configuration of an embodiment of the present invention. In FIG. 1, reference numeral 1 is an information source such as a personal computer or an image reading apparatus, and 2 is a signal processing means for processing the information sent from the information source 1. The output signal of the information source 1 is input to the signal processing means 2 as a character information signal and a video information signal and processed. Reference numerals 3 and 4 denote liquid crystal driving means to which the output of the signal processing means 2 is input.

Reference numeral 5 is a monochrome liquid crystal panel, 10 is a color liquid crystal panel, and 6, 7, 11, and 12 are polarizing plates.
Reference numerals 8 and 13 denote light source units, which are diffuser plates 8a,
It is composed of a light source 8b and a reflector 8c. 9, 1
Reference numerals 4 are projection lens units, respectively.

The output signal of one liquid crystal driving means 3 is input to the black and white liquid crystal panel 5, and the output signal of the other liquid crystal driving means 4 is input to the color liquid crystal panel 10. Reference numeral 15 denotes a screen, and the light from the light source unit 8 that has passed through the black and white liquid crystal panel 5 projects a display image on the black and white liquid crystal panel 5 on the screen 15. Similarly, the color liquid crystal panel 1
The light from the light source unit 13 that has transmitted 0 projects a display image of the color liquid crystal panel 10 on the screen 15.

FIG. 2 shows a concrete example of the signal processing of the signal processing means 2 described above. In FIG. 2, A is a character information signal and B is
Is a video information signal, C is a character display signal, and D is a video display signal. The character information signal A and the video information signal B are supplied from the information source 1 to the signal processing means 2. The character display signal C and the video display signal D are input to the liquid crystal driving means 3 and 4, respectively. 2a is a region separating means, 2b is an image processing means, 2c is an RGB generating means, 2d is a character extracting means, and 2e is a character adding means.

The character information signal A is inputted to the area separating means 2a and the character adding means 2e. The area separating means a determines the character area of the character information signal A and outputs the area signal to the image processing means 2b. The character extracting means 2d detects, for example, a character existing area and outputs a character area signal and a processing information signal to the video processing means 2b. The image processing unit 2b processes the input image information signal B according to the output of the area separating unit 2a, outputs the signal to the RGB generating unit 2c, and outputs the image display signal D to the output of the RGB generating unit 2c.
To get

Further, the character extracting means 2d uses the video information signal B
A character area is drawn from the character area, a character signal is generated, and the character signal is output to the character adding means 2e. Character addition means 2
At e, a character signal is added to the character information signal A according to the output of the character drawing means 2d, and the character display signal C is obtained at the output. Also, the image processing means 2b and the character adding means 2e
Is controlled to be executed or not executed by a control means (not shown).

Next, the operation of the configuration of the first embodiment of the present invention shown in FIGS. 1 and 2 will be described with reference to FIGS.

FIG. 4a schematically shows a display image by only the video information signal B, and FIG. 4b schematically shows a display image by only the character information signal A. The area separating means 2a determines the character area of the character information signal A, and based on this determination, the image processing means 2b fixes the signal of the specific area of the image information signal B to a constant luminance or a constant hue,
An image display signal D is obtained via the RGB generating means 2c.
This image display signal D is supplied as a display image signal of the color liquid crystal panel 10 via the liquid crystal driving means 4, and the display image of the color liquid crystal panel is projected on the screen 15.

On the other hand, the character information signal A is the character addition means 2
For example, a signal obtained by partially binarizing the video information signal B is added via e, whereby the character display signal C is obtained. This character display signal C is applied to the liquid crystal driving means 3
Is supplied as a display image signal of the black and white liquid crystal panel 5 and the display image of the black and white liquid crystal panel 5 is projected on the screen 15. As a result, as shown in FIG.
The display image shown in is obtained.

FIG. 5 shows an embodiment of a display different from that of FIG. At this time, it is assumed that the video information signal B is not input. 5a represents the output of the image processing means 2b.
When the area separating means 2a obtains the area signal and the color signal, the image processing means 2b generates a signal (a in FIG. 5) to which a color is added for each area. The image of FIG. 5c is displayed on the screen 15 by combining the image of the character information signal A of FIG. 5b and the image of the signal of FIG. 5a.

(Other Embodiments) FIG. 3 shows the essential parts of the configuration of another embodiment of the present invention. In FIG. 3, 16 is a half mirror, 17 is an objective lens, and 18 is an eyepiece lens. The display image of the monochrome liquid crystal panel 5 and the display image of the color liquid crystal panel 10 are combined by the half mirror 16, and the display image is connected to the retina of the eye of the user through the objective lens 17 and the eyepiece lens 18.

The configuration of this embodiment is effective when the present invention is implemented in a small size, such as an electronic viewer. The light sources 8 and 13 are not limited to those shown in FIG. 1, but may be surface emitting fluorescent lamps.

Other configurations and operations are the same as those of the previous embodiment shown in FIGS. 1, 2, 4 and 5.

[0027]

As described above, according to the present invention,
Not only is it possible to display textual information and natural images without reducing the resolution of textual information, but also according to the input signal,
By processing the display images of the two liquid crystal panels, there is an effect that the character information and the natural image are separated from each other and an effective visual expression can be performed.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a first embodiment of the present invention.

FIG. 3 is a configuration diagram of a second embodiment of the present invention.

FIG. 4 is an explanatory diagram of the operation of the present invention.

FIG. 5 is an explanatory diagram of the operation of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Information source 2 Signal processing means 5 Black-and-white liquid crystal panel 10 Color liquid crystal panel 16 Harm mirror

Claims (4)

[Claims] 1. A video display device comprising a plurality of video display means and a synthesizing means for optically synthesizing a plurality of display videos obtained by the video display means, the video display means comprising at least one of the video display means. An image display device characterized in that at least one image display unit displays a color image, and at least one image display unit other than the image display unit displaying the color image displays a monochromatic image. 2. A color liquid crystal panel in which a single plate color filter is laminated, a single plate monochrome liquid crystal panel, and an image signal of a natural image is supplied to the color liquid crystal panel,
Signal processing means for supplying an image signal of a text image to the monochrome liquid crystal panel, and an illumination optical system for illuminating the display image of the color liquid crystal panel and the display image of the monochrome liquid crystal panel to display a composite image on the screen. An image display device comprising: 3. An illumination optical system including, instead of the illumination optical system, a half mirror for synthesizing a transmission image of a display image of the color liquid crystal panel and a transmission image of a display image of the monochrome liquid crystal panel, and the half. The image display device according to claim 2, further comprising an eyepiece lens that monitors an image that has passed through the mirror. 4. The signal processing means extracts a character from the image signal of the natural image, adds the extracted character to the image signal of the text image, and a character area of the image signal of the text image. 3. The video display device according to claim 2, further comprising: a unit that determines the determined area and removes the determined area of the character region from the image signal of the natural image.