JPS592901B2 - thermal display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a display device using a heat-sensitive display made of a reversible thermochromic material, in which an image recorded on the heat-sensitive display is projected onto a screen by optical means. The purpose of this invention is to obtain a thermal display device that can display extremely fine color images on a large screen.

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a flexible heat-sensitive display body formed in the shape of an endless band, which is wound around a driving pulley 3 and driven pulleys 4 and 5 connected to a motor 2. It is supported by j0, and is moved in the direction of arrow A in synchronization with an external signal.

Reference numeral 6 denotes a heat insulator constructed by applying a Nesa film as a heating resistor to one side of transparent glass, for example, and in order to maintain the display area of the heat-sensitive display element 1 at a certain temperature, a heat insulator 6 is provided on the back side of the display area.
5 are installed, one end of which also serves as a platen.

T is a heating element such as a thermal head used in a thermal printer, and is installed in the width direction of the thermal display 1 at one end of the heat insulating body 6 and is in contact with the surface of the thermal display 1. This heating element T generates heat in response to a signal by a drive circuit 8, so that an image can be recorded on the thermal display 1. Reference numeral 9 denotes a cooler composed of, for example, a Peltier element and a metal piece, and is installed in the middle of the transfer route of the heat-sensitive display body 1.
are in contact with each other.

Reference numeral 10 denotes a light source for illuminating the image recorded on the heat-sensitive display body 1, and is installed behind the heat insulating body 6.

Reference numeral 11 denotes a lens for efficiently projecting the light from the light source 10, and is installed between the light source 10 and the heat insulator 6.

12 is the above-mentioned thermosensitive 10 display body 1, heating element T, and cooler 9.
It is a housing that houses a light source 10 and the like, and has an opening 13 at the position of the display area of the heat-sensitive display 1.

Reference numeral 14 denotes a lens for enlarging and projecting the image recorded on the thermal display body 1, and is disposed opposite to the front of the display area.

15 is a reflection mirror; 16 is a screen; the image from the lens 14 is projected onto the screen 16 by the reflection mirror 15;
It is starting to be displayed.

1? is a correction pen for correcting or adding images recorded on the thermal display body qζ-1, and is composed of, for example, a cooling element, a thermal heater, a metal piece, etc., and the pen tip is heated to a desired temperature. It has become possible to control the

FIG. 2 is a partially enlarged view showing the structure of the thermosensitive display body 1.
Two heat-sensitive sheets 18 and 19 with different background colors are joined together.

The thermosensitive sheets 13 and 14 are each constructed by coating a transparent sheet with a thermochromic material having reversibility and hysteresis characteristics in transmittance change characteristics due to temperature changes. Thermochromic materials are well known and come in a variety of colors, but they all have the property of becoming colorless and transparent at a certain temperature. FIG. 3 is a diagram showing the temperature versus transmittance change characteristics of the heat-sensitive sheets 18 and 19 constituting the heat-sensitive display 1, in which a shows the characteristics of the heat-sensitive sheet 18, and b shows the characteristics of the heat-sensitive sheet 19. As is clear from the figure, the temperature versus transmittance change characteristics of the two are different.

Therefore, if you want to keep the heat-sensitive display body 1 at a temperature Ts and make only the heat-sensitive sheet 18 transparent, for example, the heat-sensitive display body 1
The transparency of the heat-sensitive sheet 18 is maintained when the temperature TWl is applied to the temperature TWl and then the temperature is returned to the holding temperature T8. If it is desired to make both the heat-sensitive sheets 18 and 19 transparent, it is sufficient to apply the temperature TW2 to the heat-sensitive display body 1 and then return it to the holding temperature Ts. In FIG. 2, A indicates the area where the ground color of the heat-sensitive sheet 18 is displayed, and B
C indicates an area in which only the heat-sensitive sheet 18 is made transparent and the background color of the heat-sensitive sheet 19 is displayed;
19 are both shown as transparent areas.

Therefore, in FIG. 1, by heating the heat-sensitive display body 1 with the heating element 7 according to the color information, the heat-sensitive sheets 18 and 19 are heated.
A color image with a background color or a transparent image, or a combination thereof can be formed on the thermal display body 1,
These images can be enlarged and projected onto a screen 16 by optical means comprising a light source 10, lenses 11 and 14, and a reflecting mirror 15 while being held by a heat insulator 6 and displayed.

To completely erase the image, move the thermal display body in the direction of arrow A to send the image to the position of the cooler 9, and the cooler 9 lowers the temperature to T.
. This is done by cooling as follows. In addition, when partially erasing, adding, or correcting an image, if the correction pen 17 is applied to the thermal display 1 and cooled to a temperature below T8, the cooled part returns to its original background color and the temperature of TWl By applying the temperature TW2, it is possible to add or modify images to the thermosensitive sheet 18, and by applying the temperature TW2, it is possible to add or modify images to both the thermosensitive sheets 18 and 19. Note that although the above embodiment is a two-color display, it is possible to display a multicolor display by further increasing the number of colors. This can be achieved by controlling the

As explained above, the present invention uses a heating element to provide an image on an endless heat-sensitive display body made of a plurality of heat-sensitive sheets made of thermochromic materials having different color and temperature-transmittance change characteristics, and uses this as a light source and a lens. Since the image is projected and displayed on a screen using optical means consisting of a mirror and a reflecting mirror, there is an effect that a color image can be displayed on a large screen.

It is also possible to perform multicolor display by controlling the heating temperature of the heating element according to color information. Further, the display resolution depends on the resolution of the cells of the heating element, and it is possible to obtain up to about 10 lines per square, so that a very fine color image can be obtained.

Another advantage is that images can be erased, added, and corrected by using a correction pen, and the thermal display can be used repeatedly. Furthermore, since it is a projection type display device that utilizes the transparency of thermochromic material, it can be used as a large screen display that can obtain extremely fine images, and can be used in various display fields.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram showing an embodiment of the present invention, Fig. 2 is a partially enlarged view showing the structure of a heat-sensitive display, and Fig. 3 is a diagram showing the change in transmittance versus temperature of the heat-sensitive display. be. 1...Thermal display body, 2...Motor, 3
... Drive pulley, 4, 5... Motion pulley, 6... Heat insulating body, 7... Heat generating element, 8.
...Drive circuit, 9...Cooler, 10...
...Light source, 11...Lens, 12...
...Housing, 13...Aperture, 14...Lens, 15...Reflector, 16...Screen, 17...Banjo Pen, 18, 19...
...Heat-sensitive sheet.

Claims (1)

[Scope of Claims] 1. A heat-sensitive display body formed in the shape of an endless band, a driving pulley and a driven pulley that support the heat-sensitive display body, and a transparent heat insulator for maintaining the display area of the heat-sensitive display body at a constant temperature. a heating element for recording an image on the thermal display, a cooler for erasing the recorded image, a light source for illuminating the recorded image from the back side, a lens for enlarging the image, and a heating element for erasing the recorded image; What is claimed is: 1. A thermal display device comprising: a reflecting mirror for projecting an image onto a screen; and means for partially erasing, adding, and modifying the image. 2. The thermal display device according to claim 1, characterized in that the thermal display device uses a thermal display body formed by stacking a plurality of thermal sheets coated with thermochromic materials having different colors and temperature versus transmittance change characteristics. 3. The heat-sensitive display according to claim 1, characterized in that a correction ben consisting of a cooling element, a thermal heater, a metal piece, etc. is used as a means for partially erasing, adding, and correcting an image. Device.