JPH0719094B2 - Optical signal converter - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an optical signal conversion device, and more particularly to an optical signal conversion device that generates ions by an optical signal to form an electrostatic image on a dielectric.

BACKGROUND ART An image forming method for forming an electrostatic latent image by generating ions is disclosed in, for example, JP-A-54-78134. In this method, as shown in FIG. 1, a plurality of first electrodes 3 extending in a first direction (left and right directions in FIG. 1) and a direction different from the first direction (paper surface in FIG. 1). A second electrode 4 extending in a direction intersecting with, and forming a matrix that intersects with the first electrode in a grid pattern,
A third electrode 5 provided on the opposite side of the second electrode from the first electrode and having an opening 8 corresponding to the matrix; and provided between the first electrode and the second electrode, Using the recording head having the first dielectric 6 having the plurality of openings corresponding to the matrix (the position where the electrode 3 and the electrode 4 intersect), the first electrode 3 was selected in a time division manner and selected. Alternating voltage is sequentially applied between the first electrode 3 and the second electrode 4, and ions are generated by the discharge between the second electrode 4 and the surface of the first dielectric 6, and the ions are generated by the second electrode 4. The potential difference between the third electrode 5 and the third electrode 5 causes the ions to be extracted from the opening of the third electrode 5, and the ions form a digital charge pattern on the surface of the solid dielectric on the conductive member.

This method has an advantage that a high electrostatic printing speed can be obtained with a small energy consumption, while when obtaining a copy from a so-called hard original, the hard original is read by an image reading device and the recording head is driven. It has the disadvantage of requiring a large system to convert it to an electrical signal. On the other hand, in the so-called ordinary electrophotographic method in which charging, image exposure, development, transfer and cleaning are repeated on the photoconductor, mechanical deterioration of the photoreceptor and surface contamination are large, and durability remains a problem.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an optical signal conversion device capable of obtaining a copy of a hard original with a simple structure.

Another object of the present invention is to provide an optical signal conversion device capable of providing a copying process in which the area of a photoconductor which is liable to cause deterioration of durability due to mechanical deterioration or surface contamination is minimized.

Still another object of the present invention is to provide an optical signal converter which can be used in a composite recording system using two systems of optical signals and electric signals.

The present invention can be used as a facsimile or a line printer in addition to a copying machine.

SUMMARY OF THE INVENTION According to the present invention, a matrix is formed with a plurality of optically transparent first electrodes extending in a first direction and a second direction different from the first direction and the first electrodes. Between the first electrode and the second electrode, and a second electrode that is provided on the opposite side of the second electrode from the second electrode and has an opening corresponding to the matrix. There is provided an optical signal conversion device comprising: a photoconductive layer provided; and a dielectric provided between the second electrode and the third electrode and having a plurality of openings corresponding to the matrix. Therefore, it is possible to obtain a copy of a hard document with a simple configuration.

Embodiment FIG. 2 is a sectional view of an optical signal converter according to an embodiment of the present invention.

The optical signal converter has a first electrode (driver electrode) 13, a second electrode 14 (discharge electrode), a third electrode 15, a photoconductive layer 16, etc., and charges a recording medium 24 in an imagewise manner. The second electrode 14 and the third electrode 15 are made of a conductive material such as stainless steel, gold, nickel, or copper having a thickness of 3 to 20 μm.

The first electrode 13 is an optically transparent conductive electrode such as Nesa glass, and is conductively joined to the photoconductive layer 16.

The photoconductive layer 16 is made of a photoconductive material such as amorphous Si, CdS, Se or an organic photoconductive material, and the thickness is appropriately selected by those skilled in the art according to the photoconductive characteristics and insulation durability of each photoconductive material. can do. It is preferable that the photoconductive layer 16 is thin in order to effectively provide an ion current described later to the recording medium.

Insulating partition layers 17 that are dielectrics are provided on both sides of the second electrode 14, and these have the function of insulating the second electrode from other electrodes. The insulating partition layer 17 is made of a polyimide film or the like, and it is preferable that this is also thin.

An alternating voltage power supply 18 is connected to the first electrode 13 and the second electrode 14 and applies an alternating voltage of 1.0 to 2.5 Kv between them. The application of the alternating voltage is controlled by the image signal from the input terminal 19. A DC voltage power supply 26 is connected to the third electrode 15, and a DC V of 1 Kv or less is applied to the third electrode 15 so as to accelerate ions.

As shown in FIG. 3 (a plan view of the optical signal conversion device of FIG. 2 seen from below (the third electrode 15 and the insulating partition layer 17 are omitted)), the first electrode 13 and the second electrode 13 14 extend in different directions to form a matrix structure. Then, the second electrode is provided at the portion corresponding to the intersection of this matrix.
14 and the third electrode 15 have openings 20 and 21 having a diameter of 50 to 150 μm. The shapes of the opening 20 and the opening 21 can be determined as necessary, and when the optical signal is input in a slit shape, it may be formed in a slit shape along it.
It is preferable in terms of resolution.

The recording medium 24 has an insulating layer 23 and a conductive substrate 25. The conductive substrate 25 is grounded.

Next, the operation principle of the ion flow control in the present invention will be described. In the present invention, the generation of ions due to air breakdown is not performed by an electrical signal from a switch or the like, but is performed by an optical signal to the photoconductive layer 16. In general, when the shape of the high voltage application part is constant, ionization of air occurs above the dielectric breakdown limit voltage according to the Passian curve.

FIG. 4 shows an equivalent circuit of the device of FIG. Reference symbol A indicates the capacitance and impedance of the photoconductive layer, and reference symbol B indicates the capacitance and impedance of the air gap. First electrode 13 and second electrode
When a high-voltage AC voltage is applied to the capacitor 14, the electric field of the opening 20 is determined by the electrostatic capacity and the resistance A and the electrostatic capacity and the resistance B. Dielectric constant in an alternating current electric field of the photoconductive material, for example, in the case of CdS, 6 to 9 in the light, 2-5 in the dark, also the specific resistance in a bright place ^{10 6} ~10 ⁸ Ωcm, 10 10 in the dark It was ~ 10 ¹² Ωcm.

When the light 27 is incident on the photoconductive layer 16, the impedance of A in FIG. 4 is lowered, and therefore the electric field strength of the opening 20 is increased, and when the light is not incident, the electric field strength of the opening 20 is decreased. Therefore, when light is incident on the photoconductive layer 16 by setting the alternating voltage by the alternating voltage power source 18 so that the dielectric breakdown limit voltage is between the upper limit and the lower limit of the electric field strength of the opening. Only in the opening 20 can the air ionization take place.

In operation, while moving the recording medium 24 facing the opening 20 using the above principle, the slit light image from the document surface is incident from the upper side of the first electrode 13 in synchronization with the recording medium moving speed. Let Since the first electrode 13 is optically transparent, the image light passes through the image light and reaches the photoconductive layer 16, whereby ions are generated only in the light incident portion based on the above-mentioned principle. An electric field formed by a DC bias applied to the recording medium 24 extracts it in the direction of the recording medium 24 and holds it on the recording medium. That is,
The electrostatic latent image charged corresponding to the bright part of the document is recorded on the recording medium 24.
Formed on. By subjecting this latent image to known reversal development, a visible image corresponding to the original document can be obtained.

This image may be transferred to another recording paper, or an insulating layer
The recording paper may be prepared by peeling 23 from the substrate 25.

FIG. 5 shows another embodiment of the present invention, in which one or both sides of the photoconductive layer 16 has an insulating layer 28 of 5-10 .mu.m.
29 are provided (FIG. 5 shows the case where both are provided). The insulating layers 28 and 19 are the photoconductive layers 16
When the photocurrent is large, the photoconductive layer 16 can be prevented from being deteriorated due to oxidation and carbonization, and therefore it is preferably provided.
However, it may not be provided in the case of having a sufficient withstand voltage within a functionally effective applied voltage range.

Next, as a specific example of the manufacturing method and structure of the device of the present invention, the case of obtaining the structure of FIG. 5 will be described. First electrode 13
NES glass was used as a coating, and 6 μm of polyester (trade name “Vylon”, Toyobo Co., Ltd.) was coated on the glass and then heat treated at 80 ° C. for 30 minutes to obtain CdS having 85 parts by weight of CdS powder and 15 parts by weight of silicon-modified epoxy. A photosensitive material of 30 μm was coated and heated at 100 ° C. for 30 minutes.

On top of this, a polyester adhesive layer (commercial item "Byron
30-SS ”Toyobo Co., Ltd.) is formed to a thickness of 6 μm, and a polyethylene terephthalate film of 6 μm is further formed thereon.
stacked m. Further, a 20 .mu.m thick stainless electrode, a polyimide resin insulating partition wall, and a 20 .mu.m thick stainless steel screen electrode were superposed on this, as shown in FIG.

A recording material (such as a paper having a back surface conductive treatment) was moved in synchronism with a space of 22 μm below the third electrode 15. First
An alternating voltage of 1.8 KV is applied between the electrode 13 and the second electrode 14,
A DC voltage of −550V was applied to the back electrode 25.

In this way, the light-dark pattern of the original was projected onto the photoconductive layer in an analog manner, recorded as an electrostatic latent image on the recording medium, and subjected to reversal development with a liquid developer, and a good copy image was obtained.

As another embodiment of the present invention, it may have a polymerization function. That is, by setting the alternating voltage so that the upper limit of the electric field strength of the opening becomes smaller than the dielectric breakdown voltage at the time of exposing the original, the generation of ions is eliminated as in the case of the black portion of the original, and as a superposition signal, it is further input from the input terminal 19. Only by applying a signal corresponding to the image to be superposed is it possible to generate ions above the breakdown voltage and superimpose relatively easily. Of course, it is also possible to use it as an overlay function by the electrode signal by the matrix while keeping the setting that the dielectric breakdown voltage is exceeded and the ions are generated during the exposure of the original.

EFFECTS OF THE INVENTION As described above, according to the present invention, by utilizing the change in AC characteristics due to exposure of a photoconductive material, ion generation due to dielectric breakdown is controlled corresponding to the structure, and the ions are electrostatically recorded. By attaching it to the material, it is possible to obtain a copy of the document with an extremely simple structure.

Further, by inputting an electric signal of an image to the optical signal converter of the present invention, it can be used as a conventionally known ion recording head, and by combining these, the superimposing function can be easily implemented.

[Brief description of drawings]

FIG. 1 is a sectional view of a known electrostatic recording head. FIG. 2 is a sectional view of an optical signal converter according to an embodiment of the present invention. FIG. 3 is a plan view of the device of FIG. FIG. 4 is an equivalent circuit of the device of FIG. FIG. 5 is a sectional view of an optical signal converter according to another embodiment of the present invention. Representative Drawing FIG. 1 Explanation of References 13: First Electrode 14: Second Electrode 15: Third Electrode 16: Photoconductive Layer

Claims (1)

[Claims] 1. A plurality of optically transparent first electrodes extending in a first direction, and a second electrode extending in a second direction different from the first direction to form a matrix together with the first electrodes. A third electrode provided on the opposite side of the second electrode from the first electrode and having an opening corresponding to the matrix; and a light provided between the first electrode and the second electrode. An optical signal conversion device, comprising: a conductive layer; and a dielectric provided between the second electrode and the third electrode and having a plurality of openings corresponding to the matrix.