JPS6088983A - Image display - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image display device, and more particularly to an image display device that projects a plurality of images using different colored lights and displays a composite multicolor image.

Conventionally, various devices for displaying color images have been proposed. For example, three types of positive images are formed on a silver halide film using a three-color separation filter, and these three types of positive images are generated using three primary color lights. There is a method of projecting on the same screen to obtain a color image, a method of overlapping projection in the same manner as above using a color-based CRT, and another method known as a light valve. However, such methods have the disadvantage that, for example, those using silver halide film require development processing time and are not instantaneous, and the image cannot be erased and reproduced.Also, those using CRT have the disadvantage that high resolution cannot be achieved. In addition to being difficult to obtain, there is also the drawback that it is difficult to obtain sufficient brightness for large-area display. Furthermore, since the light pulp method scatters or diffracts light, the projection optical system is complicated and the apparatus is large-scale, such as constantly forming an oil film in a vacuum.

SUMMARY OF THE INVENTION An object of the present invention is to solve the drawbacks and problems that the conventional color image display apparatuses have, and to provide a color image display apparatus with a simple structure, brightness, and higher resolution.

In the present invention, multiple images corresponding to color separation positive images of the color image to be displayed are formed in a plurality of image forming areas defined on one image carrier by various means. , each of these images at a predetermined wavelength corresponding to the color separation,
That is, the present invention provides an apparatus capable of forming a desired color image on a screen by superimposing and projecting each of the three primary colors of light and synthesizing them based on the principle of additive color mixing.

Accordingly, the gist of the present invention, which is an air-like device for realizing such an invention, is to provide a rotating transparent image bearing member having a plurality of image forming areas, and a rotating transparent image bearing member having a plurality of image forming areas. an image forming means for forming, in each of a plurality of image forming areas, an image corresponding to a color-separated image of a predetermined image to be displayed (using conventional electrophotographic toner or other transparent powder); and the image carrier. means for relatively moving the image forming means, means for illuminating and projecting the plurality of particle images on the image carrier with light of three primary colors corresponding to each color separation image, and superimposing each projected light on a display surface. and an image forming means for forming an image.

According to such an apparatus, each image formed in a plurality of image forming areas on the same image carrier is formed by a single image forming means, so that each color separation image can be formed without any mutual positional deviation. It is easy to adjust the so-called registration, which always forms images at regular intervals, and since it uses an undefined powder image on the image carrier, it is possible to form images at high speed and repeatedly when displaying a large number of continuous images. Moreover, since the powder image on the image carrier is used as the object of the display image, high resolution image quality can be obtained.Furthermore, by using a transparent body as the image carrier, the illumination is projected through the image carrier. Because it uses light, it has excellent effects such as being able to obtain extremely bright images.

The present invention will be described below based on embodiments shown in the drawings.

FIG. 1 shows an embodiment of the present invention, in which (a) is a front view and (b) is a side view. The image carrier 1 in this example is
As shown in FIG. 2, it is constructed as a laminate belt consisting of a transparent substrate 2 made of a 2-stick film, a transparent conductive layer 3 made of indium tin oxide, etc., and a dielectric layer 4 having insulation or appropriate resistance. As shown in FIG. 1(C), it is suspended from a plurality of rows 25 to 8 and is provided so as to be rotatable in the direction of the arrow. An image recording device 9 serving as an opaque powder image forming means is disposed on a part of the rotational track of the belt between the image carrier 1 and close to the outside of the track. The image recording apparatus in this example has a non-magnetic cylinder 10. As shown in an enlarged view in FIG. Rotating magnet inside 11. and a magnetic multi-needle electrode 12, a rotating magnet 11 conveys conductive magnetic toner 13 as powder on a non-magnetic cylinder 10, and a signal voltage corresponding to an image is applied to the magnetic multi-needle electrode 12. It is possible to apply a device that is operated to form a toner image (by doing so), for example, the method described in Japanese Patent Publication No. 51-46707.

The image carrier 1 of this example has three toner images in a certain mutual positional relationship within a range where a straight line can be formed between the rows 26 and 7 shown in FIG. 1(A). The image bearing member 1 is rotated in relation to the image recording device 9, and images to be displayed are formed at predetermined intervals. Three negative images corresponding to the three-color separation positive image are formed using conductive magnetic toner. Further, the image carrier 1
is rotated by a rotary drive device (not shown), and this rotation is performed intermittently at fixed timing. That is, after forming a predetermined toner image on the image carrier 1, this is to be stopped at the illumination position (in this example, the position between the rollers 6 and 7 shown in FIG. 1 (())). The stop timing of the image carrier 1 is controlled by detecting an opaque mark provided on the transparent image carrier 1 using a light source and a light receiving element, or by detecting a part of the formed toner image. It's okay.

In this example, the three toner images formed on the image carrier 1 are generated by applying a signal voltage to the magnetic multi-needle electrode 12 of the image recording device 9 to three-color separation of the image to be displayed, and an Ie di-image. Since the three toner images are provided independently so as to correspond to each other, it is common for the three toner images to have different shapes.

Next, the illumination, projection, and imaging system of this example for displaying a color image based on the three toner images will be described. Only light of a required wavelength is selectively transmitted through a filter 15 such as a filter or a colored glass filter, and the reflected mirror 16 illuminates the image carrier l. Note that the illumination device of this example includes independent light sources 14 a and 14 b corresponding to the three toner images.
.

14c1 Red, green, blue filters 15a, 15b.

15c1 and reflective mirrors 16a, 16b, 16
It is composed of c.

The projection and imaging device transmits the image on the image carrier 1 illuminated by the illumination device to the mirrors 17 and 18 and each lens 1.
Display surface 20 via 9 m + 19 bt 19 c
It is provided so that images are formed and projected while being superimposed on top of each other. When the display surface is fixed as in this embodiment, the lenses 19a-a may also be fixed, but when projecting onto an external screen whose position changes, each lens is movable to adjust the optical path direction. In order to match the color misalignment, it is necessary to adjust the distance between each lens at a minimum. In this example, Fresnel lenses 21a and 21b are provided for each toner image in close proximity to the illumination device side of the image carrier 1.

21c to effectively direct the light from the lighting device to lens 1.
9a, 19b, and 19c.

Here, the display image in which the illumination projection light based on the three toner images is superimposed is, in short, three positive images corresponding to images obtained by color-separating one image using red, green, and blue filters, respectively. ,green.

This corresponds to what is displayed when synthesized in the evening light.

For example, in FIG. 1A, if the filter 15a is a red filter, the image on the recording medium 1 on the Fresnel lens 2'lJL corresponds to the color separated by the red filter. Normally, a color image is represented by red, green, and blue luminance signals, so in this embodiment, these signals may be inverted and used as the image input signal. As described above, in this example, the image to be displayed is displayed on the display surface 20 as a composite of three color-separated images.

In the embodiment described above, the image on the image carrier 1 is automatically erased by forming the next image. A separate cleaning means may be provided in consideration of cases where the resistance value is high or the magnetic field acting on the conductive magnetic toner is weak. In addition, in the above embodiment, when changing the color tone of a displayed image, an ND filter can be added in addition to a yellow filter in which the brightness ratio of each light source is changed, and an image formed on a recording medium can be added. Fine adjustment of color balance can be easily performed by changing the density of .

Although the image display of the present invention is realized by the embodiments described above, it is not necessarily limited to the frame only, and various other modes can be considered.

For example, the images to be displayed are not necessarily limited to full-color display, but can be any combination of colors as necessary. You can also. Also, instead of overlapping the entire screen, partial overlapping may be performed. An example of such use is shown in FIG. 3. That is, toner is applied to each of the three image areas on the transparent image carrier 1, leaving a circular part (a positive image is circular; this is R, G, B).
By projecting the light onto the screen with the light rays of It is also easy to change the position of the circle by adjusting it as appropriate.

In addition, because the device is small, one or two front-cut light sources may be used, and light separated by color using a dichroic mirror may be used, or the image may be formed on a wall outside the device. , a screen, etc. can also be used.

Furthermore, in the embodiments described above, the illumination light is transmitted in one direction, but the apparatus may be made more compact by arranging the illumination light source on the imaging lens side, for example. Needless to say, in this case, a mirror or the like is required to reflect the illumination light.

Further, the arrangement of color filters and the like is not limited to that of the above embodiment, and the Fresnel lens may also be retracted to a position where it does not come into contact with the image carrier except during illumination. Furthermore, regarding the toner forming means, not only an image recording device using a magnetic multi-needle electrode as in the above embodiment, but also a powder toner image forming means on a light-transmitting or light-reflecting image carrier. Other schemes are also available. For example, it is also possible to use a method in which a toner image is formed on an electrophotographic photoreceptor and transferred to an image carrier belt using a conventional electrophotographic method.

Referring to FIG. 4, an example of another powder image forming method suitable for use in the present invention will be described. The image carrier 22 is supported by a frame 23 made of a transparent plastic film. The powder image is formed by moving the multi-needle electrode 24 and the developing device 25, which is conductive and magnetic and contains component toner, at the same speed in the direction of the arrow.

Three screens of images are formed on the image carrier 22 as in the previous embodiment and are used for projection. The details of such an image forming method are also disclosed in Japanese Patent Publication No. 30228/1983. As explained above, in the present invention, since a plurality of images are formed on the same image carrier with an interval of one foot, the intervals between the images are constant and the positions do not shift. There is no difficulty in registering superimposed images, it is possible to form images at high speed, it has the advantage of being able to switch screens quickly, and it also uses a transparent image carrier. In some cases, a very bright display image can be obtained, making it extremely useful as an optimal device for quickly displaying high-resolution large-screen images.

[Brief explanation of the drawing]

FIG. 1(a) is a front view of an image display device showing an embodiment of the present invention, FIG. , FIG. 3 is a diagram illustrating an example of the use of the device, and FIG. 4 is a diagram illustrating an example of another powder image forming method. 1... Image carrier 2... Transparent substrate 3 ...Transparent conductive layer 4...Dielectric layer 5 + 6 +
7-8... Roller 9... Image recording device 10... Non-magnetic cylinder 11... Rotating magnet 12... Magnetic multi-needle electrode
13... Toner 14a, 14b, 14
c - Light sources 15a, 15b, 15cm74 Luther 16a, 16b, 16c---Reflection mirror 17.17...Mirror 19a, 19b, 19c---Lens 2
0... Display surface 21 a, 2 l b, 21 c - Fresnel lens 22... Image carrier 23... Frame 24... Multi-needle electrode 25... Developing device. Figure 1 (a)

Claims (1)

[Claims] A rotating transparent image carrier having a plurality of image forming areas on its surface, and opaque grains corresponding to an image corresponding to a color separation image of the image to be displayed for each of the plurality of image forming areas of the image carrier. a single image forming means for forming a body image; a means for relatively moving the image carrier and the image forming means; What is claimed is: 1. An image display device comprising: means for illuminating and projecting light with light; and imaging means for superimposing the respective projected lights to form an image on a display surface.