JPH0766243B2 - Drawing device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a drawing apparatus.

[Outline of Invention]

This invention makes it possible to perform drawing (input) and display on the same screen by providing a transparent tablet board in close or close proximity to the front surface of the display screen of the liquid crystal display device in the drawing device. The parallax is not generated.

[Conventional technology]

There is a tablet, a mouse, etc. as the input means of the drawing device, and a CRT display as the display means. However, when the absolute coordinates of drawing () and display are made to correspond one to one, the combination of the tablet and the CRT display is used. Is common. And at this time, as a tablet,
A type that puts the tablet board at hand and draws (inputs) on it with a tablet pen, etc., and a type that the tablet board is transparent and is installed on the front of the CRT (picture tube) and draws on it with a tablet pen etc. There are some.

[Problems to be solved by the invention]

However, when the tablet board is placed at hand, the drawing position and the display position are completely different, and the operability becomes extremely poor.

On the other hand, in the case of the transparent tablet board, since the drawing position and the display position are the same, the operability is improved. However, even in this case, a disparity occurs between the drawing position and the display position due to the curvature of the screen of the CRT or the thickness of the screen glass. Moreover, this parallax changes depending on the deflection distortion of the CRT and the viewing position. In addition, the deflection position of the CRT, that is, the display position, may be affected by contrast, brightness, geomagnetism, or the like and may shift.

Furthermore, since the CRT worker's eyes are approaching, the worker is greatly fatigued due to flicker. In addition, it is impossible to perform high-quality display such as writing on paper with high resolution.

The present invention seeks to eliminate these problems.

[Means for solving problems]

As shown in FIG. 1, an example of the present invention is a liquid crystal cell in which the transmission state is changed by the irradiation of laser light, and the transmission state is maintained even when the irradiation of laser light is stopped, and this liquid crystal cell. Writing means for writing to the liquid crystal cell with laser light, scanning means for controlling the writing position of the laser light with respect to the liquid crystal cell in response to the detection pulse of the tablet pen, and full erase and unmodulated laser light for applying an erase voltage to the liquid crystal cell. And an erasing means including partial erasing for applying an erasing voltage, a memory means for storing display data written in the liquid crystal cell and accessing as necessary, and a projection means for projecting an image written in the liquid crystal cell. , A flat screen for displaying the image projected by the projection means, and a transparent screen provided in close contact with and integrated with the screen. When a drawing is performed on the tablet board by the let disk, the tablet pen that inputs the coordinates in cooperation with the tablet disk, the writing means is modulated by the display data based on the output of the tablet disk. A drawing control means, which is controlled by a laser beam, writes in a corresponding portion of the liquid crystal cell, and displays a trajectory of the tablet pen at a position corresponding to a drawing position on the screen. It is a device.

[Action]

When drawing on the screen with a tablet pen etc., the coordinates are detected, and the detected output causes the display at the coordinate position where the drawing was made, so that drawing (input) and display can be done on the same screen. This is done so as not to cause parallax between the two.

〔Example〕

In FIG. 1, the liquid crystal display device writes a display image in a liquid crystal cell by irradiating the liquid crystal cell with a laser beam, and enlarges and projects this image on a screen by a projection means for display. The image has two levels of density, white or black.

And, (10) shows the liquid crystal cell, which, when irradiated with laser light, converts the laser light into heat energy and heats the irradiated part, and this heating causes a phase transition in the liquid crystal. When the alignment state is disturbed and the laser light is stopped, the irradiated part is rapidly cooled, and the disordered alignment state of the liquid crystal remains as it is, so that the irradiated part becomes opaque.

For this reason, the liquid crystal cell (10) is constructed, for example, as shown in FIG. That is, in the figure, (11) is the liquid crystal filled in layers, and the alignment layer (12),
(13) and transparent electrodes (14) and (15) are provided. The electrode (14) is formed on a glass plate (16), and the electrode (15) is a cold filter (17) that reflects laser light.
Is formed on the glass plate (18) with the space between. And
The laser light for writing is emitted from the glass plate (16) side, and the projection light from the projection means is projected from the glass plate (18) side.

In this case, the liquid crystal (11) is a cyanobiphenyl-based liquid crystal, for example, a mixture of octylcyanobiphenyl at a ratio of 40 mol% and decylcyanobiphenyl at a ratio of 60 mol%. For example, 1,3 (1,4-dimethyl-7-isopropylazulenyl) -cyclobutenediiylium is added as a dye to enhance the absorption and transmission efficiency of laser light, and the liquid crystal is directly heated by laser irradiation, The resolution is improved.

The liquid crystal (11) containing the dye is in a smectic A (SmA) phase state in a normal state, and is in a transparent state with an oriented texture. When this is irradiated with laser light in a voltageless state and heated, a phase transition occurs in the nematic (N) phase and further in the liquid phase (alignment liquid). The phase transition temperature from SmA phase to N phase is 4
The phase transition temperature from the N phase to the liquid phase is 45.2 ° C at 4.8 ° C.
When this heating part is rapidly cooled after laser irradiation, it undergoes a phase transition of liquid phase → N phase → SmA phase, and the liquid crystal molecules in this part do not return to the unidirectional alignment state, which is a so-called focal conic structure light scattering state. Then, laser writing is performed. This light scattering state is maintained without being broken unless an external voltage is applied or a high external temperature is applied again.

When a high voltage is applied from the outside in the light-scattering state of the SmA phase, the SmA phase becomes transparent (orientated texture) and the entire surface can be erased.

Furthermore, the light scattering state of the SmA phase (focal conic structure)
When heated with a laser beam, the phase transitions from SmA phase to N phase to liquid phase, the laser beam irradiation position is erased by cooling from the liquid phase (low voltage application), and the phase transitions from N phase to SmA phase and is transparent. A state (oriented texture) is obtained and partial erasing is performed.

Also, as an example, the effective area of the liquid crystal cell (10) is 20 mm in length.
× width 20 mm, resolution is 2000 pixels vertically × 2000 pixels horizontally.

Further, in FIG. 1, (20) shows a writing means by laser light. The writing means (20) turns on or off the laser light for each pixel according to the display data, and irradiates the liquid crystal cell (1) with the laser light to write an image in the cell (1).

That is, when the display data is taken out from the microcomputer (70) described later, this display data is supplied to the monostable multivibrator (21) to make a pulse having a pulse width of 2.5 μs per pixel, and this pulse is driven. It is supplied to the laser diode (23) through the circuit (22). The diode (23) is, for example, a GaAlAs semiconductor laser and outputs near infrared light having an output of 30 mW and a wavelength of 780 nm.

Therefore, the laser light modulated on or off according to the display data is output from the diode (23), and this laser light passes through the galvano mirror (24) → lens (25) → prism (26). Supplied to (10).

Further, in this case, the scanning means (30) scans the liquid crystal cell (10) with laser light. That is, although this scan includes raster scan or vector scan, the digital horizontal address signal Ax and vertical address signal for designating the X coordinate and the Y coordinate of the scan position (laser light irradiation position) from the microcomputer (70). Ay is taken out, these signals Ax and Ay are supplied to the D / A converters (31) and (32) to be analogized, and then the horizontal scanner (35) and the vertical scanner (through the drive circuits (33) and (34)). 36), so that the galvanometer mirror (24) is driven in the horizontal and vertical directions by these scanners (35) and (36), and the laser light is delivered to the coordinates of the liquid crystal cell (10) designated by the signals Ax and Ay. Is irradiated.

Further, (41) shows an erase circuit, which is a microcomputer (7
Controlled by (0), an alternating voltage ER of a predetermined level is taken out, and this voltage ER is applied to the electrodes (14) and (14) of the liquid crystal cell (10).
It is supplied to (15) and erased. However, this erasing includes a full erasing in which the entire surface of the cell (10) is erased and a partial erasing in which only a part is erased, and these are performed as shown in the following table.

In the partial erasing, the low voltage erasing voltage ER is supplied to the entire surface of the cell (10) and the laser light is irradiated only to the portion to be erased.

Further, (42) represents a temperature control circuit, whereby the liquid crystal cell (10) is held (biased) at 43.3 ° C., which is 1.5 ° C. lower than the first phase transition temperature of 44.8 ° C. in a steady state, and therefore, the steady state. At times, the liquid crystal (11) is kept in the smectic A phase state.

Further, (50) indicates a projection means, by which the image on the liquid crystal cell (10) is enlarged and projected on the screen (58).
That is, projection light is taken out from a light source, for example, a 150 W halogen lamp (51), and this projection light is converted into an infrared filter (52) → condenser lens (53) → ultraviolet filter (5
4) → mirror (55) → the liquid crystal cell (10) is irradiated through the optical path of the lens (56), and the light transmitted through the cell (10) is projected through the prism (26) onto the screen (58) by the projection lens (57). To be done. Therefore, the image written in the cell (10) is enlarged and displayed on the screen (58).

The screen (58) is the display screen of the projection means (50) and at the same time, the tablet board (61) of the tablet (60) is integrated. Therefore, for example, as shown in FIG. Is configured. That is, in the figure, (59) is a flat and transparent glass plate, and the surface on the projection light side is made a ground glass surface (59A) to form a display screen (58). On the surface opposite to (59A), a plurality of transparent and striped electrodes (63) are arranged in the horizontal direction so as to be separated from each other. Further, (64) is a flat and transparent glass plate, and a plurality of transparent (stripe-shaped) electrodes (65) are vertically separated from each other on the surface facing the glass plate (59). It is arranged. The glass plates (59) and (64) are in close contact with each other with an insulating layer (not shown) in between to form a transparent tablet board (61). The thicknesses of the glass plates (59) and (64) are, for example, 1 mm and 3 mm, respectively, and the sizes thereof, that is, the screen (58) and the tablet board (61) are, for example, A4 size.

Further, (66) is a tablet pen, in which the electrode (pen tip) is insulated from the grip, and a voltage (scan pulse) is supplied to the electrodes (63) and (65) of the tablet board (61). At that time, it is supposed to catch the electric field.

Also, (70) indicates a microcomputer that performs various controls, and (7)
1) is the CPU, (72) is the ROM in which the control program is written, (73) is the work area RAM, (74) is the input port, (75) and (76) are the output ports, These circuits (72) to (76) are connected to the CPU (7
1) connected to. In addition, the CPU (71) has a bus (7
A full keyboard (77) and a display memory (78) are connected through a disk drive 9), and a floppy disk device (82) is connected through a floppy disk drive FDC (81). In this case, the display data written in the liquid crystal cell (10) is accessed in the memory (78), and for example, the cell (10) has a capacity of 2000 bits vertically × 2000 bits horizontally.

Then, when the keyboard (77) is operated to enter the writing mode, ER = 0 is set and a scan pulse for the tablet board is formed in the microcomputer (70), and this pulse is transmitted through the port (75) to the electrode (63), It is sequentially supplied to (65) and scanning is performed. Then, at this time, when the tablet pen (66) is applied to the glass plate (64), a scan pulse is detected by the tablet pen (66), and this is taken into the microcomputer (70) through the port (74) through the shaping amplifier (67). Be done.

Then, in the microcomputer (70), the tablet pen (6
The scan pulse detected by 6) is the electrode (63),
It is determined which electrode of (65) is being scanned, and the coordinates indicated by the tablet pen (66) are determined from this determination result, and the address signals Ax, Ay are calculated according to these coordinates. The signals Ax and Ay thus formed are supplied to the D / A converters (31) and (32) through the port (76), and the display data is supplied from the port (76) to the multivibrator (21). Therefore, the corresponding pixel (position) of the liquid crystal cell (10) is irradiated with laser light to make this pixel opaque, and this pixel is projected onto the screen (58) by the projection means (50). A black dot is displayed at the position where the pen (66) is applied.

At this time, the bit corresponding to the coordinate in the memory (78) is set to "1".

In this way, when drawing is performed on the tablet board (61) with the tablet pen (66), dots are written in the corresponding portion of the cell (10) and the pen (6
The trajectory of 6) is displayed. At the same time, the corresponding bit in the memory (78) is also set to "1".

Further, when the keyboard (77) is operated to enter the erase mode, the erase voltage is supplied to the cell (10) to erase the entire surface or the designated portion of the pen (66). At this time, the corresponding bit in the memory (78) is also reset to "0".

When the keyboard (77) is operated after the drawing is completed, the display data of the memory (78) at this time is saved in the floppy disk device (82). When the display data of the floppy disk device (82) is designated to be loaded, the display data is loaded into the memory (78) and the display data is sequentially read and written into the cell (10). Therefore, the image saved in the floppy disk device (82) is displayed on the screen (58).
To be played.

Thus, according to the present invention, it is possible to perform drawing. In this case, in particular, according to the present invention, the tablet board (61) is made transparent and is closely attached to and integrated with the display screen (58). Therefore, the drawing position and the display position are the same, and therefore the operability is excellent.

Also, tablet board (61) and display screen (58).
Is a flat plate and has a thin thickness of 1 to 2 mm, so that there is almost no parallax between the drawing position of the tablet pen and the displayed locus. In addition, the liquid crystal cell (1
Since the image written in (0) is projected on the screen (58) for display, the distortion of the displayed image is
Much smaller than the image displayed by, and
It is not affected by contrast, brightness, geomagnetism, etc., and therefore does not cause parallax.

Furthermore, since the image of the liquid crystal cell (10) is projected on the screen (58) by the light of the lamp (51), display is performed.
There is no flicker and there is almost no strain on the operator's eyes. Also 2000 for A4 screen (58)
Since it can be displayed with a resolution of dots x 2000 dots, it is possible to display with high resolution and high quality.

In addition, in the above, the tablet board (61) is a flat plate,
In addition, any transparent one may be used, and for example, the electric field from the tablet pen (66) may be read, or a pressure type may be used.

〔The invention's effect〕

According to the present invention, it is possible to perform drawing, but in this case, in particular, according to the present invention, since the tablet board (61) is made transparent and is closely attached to the display screen (58), The drawing position and the display position are the same, and therefore the operability is excellent.

Also, tablet board (61) and display screen (58).
Is a flat plate and has a thin thickness of 1 to 2 mm, so that parallax hardly occurs between the drawing position of the tablet pen and the displayed locus. In addition, the liquid crystal cell (1
Since the image written in (0) is projected on the screen (58) for display, the distortion of the displayed image is
Much smaller than the image displayed by, and
It is not affected by contrast, brightness, geomagnetism, etc., and therefore does not cause parallax.

Furthermore, since the image of the liquid crystal cell (10) is projected on the screen (58) by the light of the lamp (51), display is performed.
There is no flicker and there is almost no strain on the operator's eyes. Also 2000 for A4 screen (58)
Since it can be displayed with a resolution of dots x 2000 dots, it is possible to display with high resolution and high quality.

[Brief description of drawings]

FIG. 1 is a system diagram of an example of the present invention, and FIGS. 2 and 3 are sectional views for explaining the same. (10) is a liquid crystal cell, (20) is a writing means, (30) is a scanning means, (50) is a projection means, (60) is a tablet,
(70) is a microcomputer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ikuo Sankyo 6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Eiji Tamaru 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo In Sony Corporation (56) Reference JP-A-58-163038 (JP, A) Actual development Shou 56-100735 (JP, U) JP-B 57-26369 (JP, B2) JP-B 55-10184 ( JP, B2)

Claims (1)

[Claims] 1. A liquid crystal cell in which the transmission state is changed by the irradiation of laser light and the transmission state is maintained even when the irradiation of the laser light is stopped, and writing means for writing in the liquid crystal cell by the laser light. Scanning means for controlling the writing position of the laser light to the liquid crystal cell in response to the detection pulse of the tablet pen; full erase for applying an erase voltage to the liquid crystal cell; Erasing means consisting of partial erasing, memory means for storing display data written in the liquid crystal cell and accessing as necessary, projection means for projecting the image written in the liquid crystal cell, and the projection means A flat screen that displays the image projected by, and a transparent tab that is provided in close contact with and integrated with the screen. When a drawing is performed on the tablet board by the let board, the tablet pen that inputs coordinates in cooperation with the tablet board, and the tablet pen draws on the tablet board, the writing means displays the display data based on the output of the tablet board. And a display control means for displaying the trajectory of the tablet pen at a position corresponding to the position where the drawing is performed on the screen by controlling with the laser light modulated by. A drawing device comprising.