JPH0746580B2 - Image forming device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an electron beam, and more specifically, image forming using an electron beam generating apparatus having a plurality of electron beam generating units. Regarding the device.

[Prior Art] In recent years, for example, Japanese Examined Patent Publication No. 54-30274, Japanese Unexamined Patent Publication No. 54-111272 (corresponding to U.S. Pat. No. 4259678), No. 56-15529 (corresponding to U.S. Pat. No. 4303930), As shown in No. 57-38528, an electron beam generator using a so-called cold cathode has been developed.

The cold cathode in the electron beam generator is a hot cathode most commonly used in the electron beam generator at present,
Due to the problem of durability, there is a great restriction to reduce the area of the electron emission surface, but there is an advantage that such restriction is scarcely applied. In addition, the hot cathode is
While it is difficult to arrange with uniform characteristics with high positional accuracy, cold cathodes are formed by a manufacturing process such as photolithography or electron beam lithography, so that multiple cold cathodes can have uniform characteristics. It has the advantage that it can be arranged and arranged with high positional accuracy. Therefore, according to such a technique or a technique similar thereto, it is possible to obtain an electron beam generator having a large number of electron beam generators, and it is expected to be applied to various image forming apparatuses including a display device. There is.

[Problems to be Solved by the Invention] However, since the electron beam generator including the plurality of electron beam generators has not yet been realized at the idea stage, the electron beam generator is used. No specific proposal has been made as to how to form an image.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image forming apparatus that forms an image by an electron beam generator including a plurality of electron beam generators.

[Means for Solving the Problems] The present invention can be modified in an image forming apparatus having an electron beam generator including a plurality of cold cathode electron sources arranged over the entire width of an image to be formed. A plurality of image data outputs each having an input terminal for inputting a drive permission signal having a pulse width, the input terminals being short-circuited to each other, and outputting image data only while the pulse of the drive permission signal is ON. An image forming apparatus comprising: a means and a plurality of driving means for driving each of the plurality of cold cathode electron sources based on the image data.

The width of the image to be formed in the present invention refers to the width or length of the image.

The present invention will be specifically described with reference to FIGS. 1 and 2 corresponding to one embodiment of the present invention. In this embodiment, an electron beam generator 2 having an electron beam generator 1 composed of a plurality of cold cathode electron sources arranged over a length corresponding to the entire width of an image to be formed, and this electron beam generator. 2 is an image forming apparatus having a deflecting unit 3 capable of deflecting the electron beam group emitted from the optical beam group 2 in a direction orthogonal to the width direction of the image. FIG. 2 shows an example of a drive circuit for the electron beam generator 2 described above. The image data DATA is output to the base of the transistor 8 via the shift register 5, the D flip-flop 6 and the NAND gate 7, and depending on the output level, The drive voltage HV is supplied to each electron beam generator 1 via the resistor 9.

[Operation] The electron beam generator 2 has a plurality of electron beam generators 1 arranged over a length corresponding to the entire width of an image to be formed.
By irradiating a group of electron beams, the electron beams are irradiated with the electron beams at one time to a certain area over the entire image width on the irradiated member 4 that forms an image by the irradiation of the electron beams. be able to. Further, the irradiation amount of the electron beam per pixel can be easily changed by changing the pulse width of the drive enable signal input to the NAND gate, that is, the output enable signal OE. On the other hand, since the electron beam group can be deflected by the deflecting means 3 in a direction orthogonal to the width direction of the image, the entire image forming area on the irradiated member 4 is not overlapped by the constant area. By irradiating and scanning with the beam group, an arbitrary image can be formed by this.

[Embodiment] As shown in FIG. 1, an electron beam generator 2 and a member to be irradiated 4 are provided to face each other, and a deflecting means 3 is arranged between them.

The electron beam generator 2 includes a plurality of electron beam generators 1 which are integrally provided by arranging a plurality of cathodes on the same substrate, for example. A cold cathode is most suitable as the cathode forming the electron beam generator 1. The cold cathodes can be arranged with extremely high positional accuracy and at a fine pitch, and in combination with scanning in only one direction, which will be described later, form an extremely high-definition, high-quality image with little distortion. be able to. Further, the electron beam generators 1 in this embodiment can be independently driven and are one-dimensionally arrayed over a length corresponding to the entire width of an image to be formed on the irradiated member 3. Here, the one-dimensional array means that the cells are arranged vertically or horizontally in one line.

The deflecting means 3 in this embodiment is composed of a pair of upper and lower plate electrodes 3
It is composed of a and 3b. The plate electrodes 3a and 3b are arranged in parallel and opposite to each other with the orbits of all the beams emitted from the electron beam generator 1 interposed therebetween. Flat plate electrodes 3a, 3
A required voltage can be applied between b through a variable voltage source (not shown). The deflection means 3
In addition to the flat plate electrodes 3a and 3b, an electromagnetic coil or the like can be used as.

The irradiated member 4 forms a fixed image or a variable image by irradiation with an electron beam. Specifically, when the present image forming apparatus is used as a display device, for example, a fluorescent screen coated with a phosphor that emits light when irradiated with an electron beam can be used. When used as a photoresist device, a member having a photoresist layer may be used.

The image forming apparatus forms an image for one screen on the irradiated member 4 by performing scanning as follows, for example. That is, the x direction (arrangement direction of the electron beam generators 1) of the image to be formed is previously stored in the line memory.
Image data of n pixels corresponding to a line is stored, and an electron beam for one line is simultaneously emitted from the arranged n electron beam generators 1 based on the data signal from the line memory. If necessary, the electron beam group is deflected in the y direction (a direction perpendicular to the electron beam and also to the x direction by a voltage applied between the flat plate electrodes 3a and 3b, and 1 in the x direction at the required position
An image for a line is formed. When the image data of the next line is stored in the line memory, the n electron beam generators 1 are driven again according to the data. At the same time, the voltage applied to the flat plate electrodes 3a and 3b is appropriately increased or decreased, and the image of the next line is formed on the irradiated member 4 with a shift of one line from the previous line. Then, by performing the above-described operations one after another, the line scan is sequentially performed on the irradiated member 4, and an image for one screen is formed.

FIG. 2 shows an example of a drive circuit of the electron beam generator 2 required to realize the scanning as described above. In the figure,
Reference numeral 5 is an n-stage shift register, 6 is an integrated unit of n D flip-flops, 2 is an electron beam generator 1 of n units
Are electron beam generators, 7 is a NAND gate, 8 is a transistor, and 9 is a resistor. DATA is time-series input image data, SCK is a shift clock for driving the shift register, DCK is a data clock for inputting data to the D flip-flop, and OE is an electron beam emission timing. In the output enable signal to be controlled, HV means a drive voltage for driving each electron beam generator 1 of the electron beam generator 2.

The operation of this circuit will be described with reference to the timing chart of FIG.

As shown in FIG. 3 (a), the image data DATA is input in time series for each line, but the shift register 6
The serial-parallel conversion of the image data DATA is sequentially performed according to the shift clock SCK (FIG. 3 (b)). Shift clock SC
When K is input n times and the serial-parallel conversion of the image data DATA for one line is completed, the image data DATA is input to the D flip-flops 6 all at once and stored in synchronization with the data clock DCK.

The output terminals of the D flip-flop 6 are NAND gates 7 respectively.
Although the image data DATA is connected to one of the input terminals, the image data DATA is at a high level when the electron beam should be emitted and at a low level when the electron beam should not be emitted. On the other hand, one input terminal of each of the n NAND gates 7 is commonly connected and connected to the output enable signal OE.

At the timing shown in FIG. 3D, when the output enable signal OE becomes high level, the NAND gate 7 whose image data DATA is high level becomes low level, and the NAND gate 7 whose image data DATA is low level becomes high level. Output. Since the output of the NAND gate 7 is connected to the base of the next-stage transistor 8, the image data
When DATA is at a high level, the drive voltage HV is supplied to the electron beam generator 1 via the resistor 9 only while the output enable signal OE is at a high level, and the electron beam generator 1 emits an electron beam. It does. At this time, the deflection necessary to form the image for one line between the flat plate electrodes 3a and 3b (see FIG. 1) at a predetermined position on the irradiated member 4 (see FIG. 1). A voltage is applied, but this is appropriately changed every time one line of electron beam irradiation is performed, as shown in FIG. 3 (e).

By sequentially performing the above-described operation for the number of lines required to form one screen, an image for one screen can be formed on the irradiated member 4.

In the above-mentioned scan, by changing the pulse width of the output enable signal OE (T _{1 in} FIG. 3D), 1
Since the irradiation amount of the electron beam per pixel can be easily changed, the adjustment can be easily performed and optimum image formation can be always performed even when the irradiated members 4 having different sensitivities are used.

Also, for example, the flat plate electrode 3 shown by the solid line in FIG.
It is also possible to form the entire screen by so-called interlacing by scanning the screen once with the deflection voltage between a and 3b, and then scanning the screen again with the voltage between the plate electrodes 3a and 3b shown by the dotted line. It is suitable for an image forming apparatus intended for display.

In the above embodiments, the electron beam generator 2 in which the electron beam generators 1 are arranged one-dimensionally is used, but the present invention is not limited to this, and the electron beam generator 1 should be formed. It may be two-dimensionally arranged as long as it is arranged over the length corresponding to the entire width of the image. Here, the two-dimensional array means that a plurality of columns are arrayed both vertically and horizontally.

[Effects of the Invention] As is clear from the above description, the image forming apparatus according to the present invention deflects the electron beam in only one direction, so that the deflecting means can be simplified and thinned.

Further, if the number of pixels in one screen and the time required to form one screen are the same, the electron beam irradiation time per pixel can be increased up to about n times as long as the conventional dot-sequential scanning with a single beam. In addition, the irradiation amount of the electron beam per pixel can be easily changed. Therefore, it becomes possible to use a material that could not be used because of its low sensitivity as a member to be irradiated.
Further, if the irradiated members have the same sensitivity, it is possible to realize a display device or the like having extremely high brightness as compared with the conventional one. From this, if the electron beam irradiation time per pixel is made equal, the number of pixels can be increased to about n times while maintaining the same brightness, and an extremely large-capacity display device can be configured. Is.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention, FIG. 2 is a diagram showing a driving circuit thereof, and FIGS. 3 (a) to 3 (f) are diagrams showing signal waveforms of respective parts in the driving circuit. . 1: Electron beam generator, 2: Electron beam generator, 3: Deflection means, 3a, 3b: Flat plate electrode, 4: Irradiated member, 5: Shift register, 6: D flip-flop, 7: NAND gate, 8: Transistor, 9: resistor.

Claims (6)

[Claims] 1. An image forming apparatus having an electron beam generator having a plurality of cold cathode electron sources arranged over the entire width of an image to be formed, wherein a drive permission signal having a variable pulse width is input. A plurality of input terminals, each of which is short-circuited to each other, outputs a plurality of image data only while the drive enable signal pulse is ON, and a plurality of cold cathode electron sources. A plurality of driving means for driving each of the above based on the image data, and an image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the image data output means includes a NAND gate. 3. The electron beam generator comprises deflection means for collectively deflecting an electron beam group emitted from the electron beam generator in a direction orthogonal to the width direction of the image. The image forming apparatus according to item 2 or item 3. 4. The deflection means applies a stepwise voltage waveform to a deflection electrode, and deflects the electron beam group so that the irradiation regions of the electron beam group do not overlap line by line on one screen. The image forming apparatus according to claim 3. 5. The drive permission signal of an OFF pulse is input to the input terminal of the image data output means at a timing at which a voltage having a stepwise voltage waveform applied to the deflection electrode is switched. The image forming apparatus according to item 4. 6. The image forming apparatus according to any one of claims 3 to 6, wherein the electron beam group exposes a resist.