JPH1117880A - Solid scanning type optical writing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a solid scanning optical writing device suitable for production of many kinds in small quantities corresponding to various kinds of print density. SOLUTION: The device is provided with an optical shutter chip array consisting many optical shutter chips arranged in a main scanning direction and a driver IC to control ON-OFF of each shutter chip based on image data. The optical shutter chip array is provided with the optical shutter chips and individual electrodes 31 formed with equal intervals corresponding to the specified print density M (e.g. 600 dpi, 400 dpi, 300 dpi) and the driver IC is provided with an output part 69 corresponding to the maximum print density N (600 dpi). And the individual electrodes 31 and the output part 69 are connected in the ratio of M/N.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state scanning optical writing device for writing an image (latent image) on a photoreceptor using a PLZT optical shutter array, an LED array or the like.

[0002]

2. Description of the Related Art Conventionally, in order to form an image (latent image) on a photographic paper, a silver halide film, or an electrophotographic photoreceptor using a silver halide photosensitive material, an optical shutter chip such as PLZT is used for each pixel. 2. Description of the Related Art An optical writing device that controls on / off of light or on / off of an LED chip is provided. This type of optical chip is driven based on image data by a driver IC juxtaposed with the optical chip array on a substrate holding the optical chip array.

Optical writing devices are required to have various printing densities (dpi, the number of dots per inch). For example, a low / medium speed machine for graphics printing is 600 dpi, and a high speed machine mainly for text printing. Then 240d
Pi optical writing device is used.
i, 300 dpi, and the like. Therefore, conventionally, it has been necessary to design and manufacture not only an optical chip array corresponding to the required printing density but also a driver IC corresponding to the printing density. However, the custom production of the driver IC has a problem that the cost is increased in the high-mix low-volume production, and there is a problem that it cannot be coped with.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a solid-state scanning optical writing device suitable for various kinds of small-quantity production corresponding to various printing densities.

In order to achieve the above object, the present invention provides an optical chip array composed of a large number of optical chips arranged in a scanning direction, and a driver IC for controlling ON / OFF of each optical chip based on image data. In the solid-state scanning type optical writing device provided, the optical chip array has optical chips formed at regular intervals corresponding to a predetermined main scanning print density M, and the driver IC corresponds to a maximum main scanning print density N The individual electrodes of the optical chip array and the output units of the driver IC are connected at an M / N ratio.

In the present invention, the optical chip array has various predetermined main scanning printing densities M including the maximum main scanning printing density N.
Is prepared. On the other hand, one of the driver ICs having an output unit corresponding to the maximum main scanning print density N is one.
The output section is connected to the individual electrodes of the optical chip at an M / N ratio. For example, assuming that the maximum main scanning print density N is 600 dpi, the output unit of the driver IC is 1 for each electrode of the optical chip array of 600 dpi.
/ 1. For the individual electrodes of the 300 dpi optical chip array, the ratio is 1/2, that is, the output units of the driver IC are connected one by one with an interval.

Therefore, according to the present invention, there is provided an optical writing apparatus in which only one type of driver IC having an output unit corresponding to the maximum main scanning print density is prepared and combined with an optical chip array corresponding to various print densities. It is ideal for high-mix low-volume production.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a solid-state scanning optical writing device according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an optical writing head 20 for writing a full-color image on photographic paper using a silver halide photosensitive material. The optical writing head 20 generally includes a halogen lamp 21, a heat insulating filter 22, a color correction filter 23, a diffusion tube 24, an RGB filter 25, an optical fiber array 26, a slit plate 27, an optical shutter module 30, an imaging lens array 35, It is constituted by dustproof glass 36.

The light emitted from the halogen lamp 21 is
The heat rays are cut by the heat-insulating filter 22 and the light quality is adjusted by the color correction filter 23 so as to match the spectral sensitivity characteristics of the photographic paper. The diffusion tube 24 is for improving the light use efficiency and reducing the light amount unevenness. The RGB filter 25 is driven to rotate in synchronization with writing by an optical shutter chip made of PLZT, and changes the passing color for each line.

The optical fiber array 26 is composed of a large number of optical fibers.
They face each other via the GB filter 25. The other ends 26b are arranged in the main scanning direction indicated by the arrow X, and emit light in a line. Slit end faces 27a, 27a of slit plate 27
Is mirror-finished, and guides light emitted from the optical fiber array 26 to the optical shutter module 30 efficiently. Further, the slit plate 27 is provided with a heater (not shown) for maintaining the optical shutter chip at a constant temperature,
Temperature control is performed based on a detection result of a temperature detection element (not shown) provided in the module 30.

The optical shutter module 30 has a slit-like opening in a ceramic substrate or a PLZT
, And driver ICs 60 and 40 (see FIGS. 4 and 5) described below are provided side by side with the optical shutter chip array. Each of the optical shutter chips is driven only by a driver IC corresponding to a predetermined pixel. A polarizer 33 and an analyzer 34 are provided before and after the module 30. As is well known, PLZT is a translucent ceramic having an electro-optic effect having a large Kerr constant, and light linearly polarized by the polarizer 33 is generated by applying a voltage to an optical shutter chip. The rotation of the polarization plane is caused by turning on / off the electric field, and the light emitted from the analyzer 34 is turned on / off.

The light emitted from the analyzer 34 passes through the imaging lens array 35 and the dust-proof glass 36 to form an image on photographic paper to form a latent image. The printing paper is transported at a constant speed in a direction (sub-scanning direction) orthogonal to the main scanning direction X.

In this type of optical writing head 20, various main scanning print densities (hereinafter simply referred to as print densities) are used.
Is required. For example, 600 dpi, 400d
pi, 300 dpi, 240 dpi, and the like. In order to cope with these printing densities, in the present embodiment, an optical shutter chip array in which optical shutter chips are formed at equal intervals corresponding to a predetermined main printing density is prepared as the optical shutter chip array. Print density (here, 600dp
i) having one output unit.

Then, as shown in FIG. 2A, the individual electrodes 31 and the output section 69 of the driver IC are connected to the optical shutter chip array of 600 dpi at a ratio of 1/1. As shown in FIG. 2B, both are connected to a 400 dpi optical shutter chip array at a ratio of 2/3. Similarly, 300 dpi and 240 dpi
2C, the optical shutter chip array of FIG.
As shown in (D), both are connected at a ratio of 1/2, 2/5.

Specifically, in an optical shutter chip array corresponding to the A3 size of the JIS standard, 600 dp
i is composed of 7,200 dot pixels (chips), and the output unit 69 of the driver IC is also composed of 7,200 pixels. At 400 dpi, the number of pixels (chips) is 2/3, that is, 4800, and the same driver IC as that of 600 dpi is used, and the output unit 69 is thinned out and connected to the individual electrodes 31 as shown in FIG. 300 dpi and 240
In dpi, the number of pixels (chips) is 3600 and 28, respectively.
80, similarly, the same driver IC as that of 600 dpi is used, and the output section 69 is thinned out and connected to the individual electrode 31 as shown in FIGS. 2 (C) and 2 (D).

The connection between the individual electrodes 31 and the output section 69 is preferably performed by wire bonding in terms of space or workability. For wire bonding, either a direct wire bonding (DWB) method in which the bonding pads are directly connected by wires or a normal wire bonding (RWB) method in which the bonding pads are connected via a wiring pattern formed on a substrate may be used.

Wire bonding is performed using an automatic machine programmed in advance. Therefore, wiring corresponding to the printing density can be easily performed by changing the program of the automatic machine. The optical shutter chip array made of PLZT is automatically machined in accordance with the required printing density. In this case, the pitch of the equally-spaced groove processing may be changed in accordance with the printing density, and can be easily achieved by changing the program of the processing machine.

That is, the driver IC has an output section 69 corresponding to the maximum printing density N, the optical shutter chip array corresponds to the required printing density M, and the individual electrodes 31 and the output section 69 are By connecting at a ratio of M / N, an optical writing device can be manufactured at low cost in response to high-mix low-volume production simply by changing the program of the production device.

By the way, the maximum printing density of 600 dp
i is 1: 1 between the individual electrode 31 and the output section 69 of the driver IC.
However, when the printing density is lower than that, there is a case where the output unit 69 is not connected to the individual electrode 31 at a predetermined interval. For the output unit 69 not connected in this manner, dummy data is generated in the control circuit 50 described below.

FIG. 3 shows the control circuit 50. The control circuit 50 is interposed between the controller 49 and the driver IC 60. The signal D- output from the controller 49
CLK and S-CLK are for generating various timing control signals. When the signals D-CLK and S-CLK are input from the controller 49, the SOS generation circuit 51 outputs a start signal SOS. Controller 49
The image data DAT is synchronized with the rising of the first start signal SOS from which the print signal PRN is output to the SOS circuit 51 (although appropriate timing adjustment is performed).
A is transferred from the controller 49 to the memory 54. The memory 54 is connected to the memory control circuit 5 in synchronization with the signal D-CLK.
2 to fetch predetermined data based on the memory address signal output from the memory 2.

The image data DATA is stored in the memory control circuit 5
2 and a memory 54 to generate a data form suitable for the configuration of the optical shutter chip array.
Transferred to As shown in FIGS. 2B, 2C, and 2D, the memory control circuit 52 generates dummy data for the output unit 69 that is not connected to the individual electrode 31 due to low printing density. Become.

The FIFO 55 absorbs a difference in processing speed between the controller 49 and the driver IC 60. The output timing and FIFO control circuit 53 generates control signals such as a shift clock signal S-CLK, a strobe signal STB, a blank signal BLK, and the like.
Transfer to 0.

FIG. 4 shows the configuration of a binary image reproducing driver IC 60 for driving the optical shutter array. This driver IC 60 uses n ICs 60 connected by a ladder chain. Each IC 60 is configured to drive 64 dots, and a shift register 61,
Latch circuit 62, gate circuit 63, level shift circuit 6
4. It comprises a driver circuit 65.

The image data DATA is transferred to the shift register 61 in synchronization with the shift clock signal S-CLK.
The signal is latched by the latch circuit 62 by the strobe signal STB. When the gate signal GATE is input to the gate circuit 63, the signal D ₁ to D ₆₄ are transferred to the driver circuit 65 via the level shift circuit 64. The driver circuit 65 are applied drive voltage Vd, the output HV ₁ ~HV ₆₄ based on the signal D ₁ to D ₆₄ from the level shift circuit 64 is applied to the light shutter elements.

Next, FIG. 5 shows a multi-value reproducing driver IC 40.
Is shown. The driver IC 40 uses n ICs 40 continuously in a ladder chain.
40 is configured to drive 64 dots, a 6-bit shift register 41, a 6-bit latch circuit 42, 6
Bit comparator 43, 6-bit counter 44,
It comprises a gate circuit 45 and a driver circuit 46.

The image data DATA is transferred to the shift register 41 in synchronization with the shift clock signal S-CLK.
The signal is latched by the latch circuit 42 by the strobe signal STB. Thereby, the number of gradations of each pixel is set. The clock signal C-CLK is counted by the counter 44,
The comparator 43 compares the latched value with the counter value, and the gate circuit 45 stops outputting when the values match. The counter 44 is cleared by the clear signal CL.

[0028] The driver circuit 46 are applied drive voltage Vd, so that the output HV ₁ ~HV ₆₄ based on the signal D ₁ to D ₆₄ from the gate circuit 45 is applied to the light shutter elements. That is, each pixel turns on the optical shutter chip for a time (pulse width) corresponding to the image data DATA.

Incidentally, in order to simplify the explanation relating to the difference in printing density, FIGS. 2 to 5 show a configuration in which a driver IC is provided on one side of the optical shutter chip array.
In this case, the image data DATA arranged in one direction is transferred to the memory 54, the FIFO 55, and the driver IC. In the case of employing a configuration in which the driver IC is provided on both sides of the optical shutter chip array, the image data DATA output from the controller 49 is divided into DATA (A) and DATA (B) by a data dividing circuit (not shown). Memory 54 and FIFO 5 provided in pairs
5 and a driver IC based on the shift signal R / L.
Transferred to

The optical writing apparatus according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the invention. In particular, as a solid-state scanning element used for optical writing, besides PLZT, LED
(Light Emitting Diode), LCS (Liquid Crystal S)
hutter), DMD (Deformable Mirror Device), FL
D (Fluorescent Device) or the like can be used. In addition, the present invention can be applied to an image writing device for a silver halide film or an electrophotographic photosensitive member or an image projection device on a display, in addition to an image writing device for photographic paper using a silver halide photosensitive material. It is.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a solid-state scanning optical writing head according to an embodiment of the present invention.

FIG. 2 shows a chip electrode and a driver I of the optical writing head.
Explanatory drawing which shows the connection state of C.

FIG. 3 is a block diagram showing a control circuit of the optical writing head.

FIG. 4 is a driver IC for binary reproduction of the optical writing head.
FIG.

FIG. 5 is a driver IC for multi-value reproduction of the optical writing head.
FIG.

[Explanation of symbols]

 Reference Signs List 20 optical writing head 30 optical shutter module 31 individual electrode 40, 60 driver IC 49 controller 50 control circuit 69 output unit

Claims (3)

[Claims] 1. A solid-state scanning optical writing device comprising: an optical chip array composed of a large number of optical chips arranged in a main scanning direction; and a driver IC for controlling ON / OFF of each optical chip based on image data. In the above, the optical chip array has optical chips formed at regular intervals corresponding to a predetermined main scanning print density M, and the driver IC has an output unit corresponding to a maximum main scanning print density N; A solid-state scanning optical writing device, wherein the individual electrodes of the optical chip array and the output section of the driver IC are connected at a ratio of M / N. 2. The solid-state scanning optical writing device according to claim 1, wherein the individual electrodes of the optical chip array and the output section of the driver IC are connected by wire bonding. 3. The solid-state imaging device according to claim 1, further comprising a control circuit for generating dummy data for an output section of the driver IC that is not connected to the individual electrodes of the optical chip array. Scanning optical writing device.