JPS60194654A - Printing head for copy - Google Patents

Abstract

PURPOSE:To realize a fast, full-color type printing head of low-cost, subminiature constitution with improved gradation reproducibility by connecting a conversion chip which has a photosensor array, signal pulse width converting means, and driving means on the same semiconductor chip electrically with a substrate on which a multiprinting means capable of direct dot gradation modulation with pulse width is mounted. CONSTITUTION:The conversion chip 10 is mounted directly on the substrate 11 mounting the array 12 of the printing means with the face down across a contact pad 14. In a figure, 13 includes a generation part and a controller for a comparison signal, etc., for pulse width conversion including a gamma correcting function. A signal 32 generated by a photosensor 20 is compared with the output 31 of the generation part 13 for the comparison signal, etc., by a comparator 21, which sends an output 34 so that the output 33 of a flip-flop 22 set with a set signal 30 previously is reset. Therefore, the pulse width is modulated according to the level of the output 32 of the photosensor 20. Thus, the multiprinting means 24 is driven by a driver 23.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a module for a copying device that does not use an electrophotographic process, and is particularly applicable to the field of copying applications for photographs (black and white and color) that require gradation. It is in.

[Prior art]

A typical conventional technology in the above field uses COD as an optical sensor array and an electrostatic printer or laser printer as a printing means to express gradation by applying dither modulation, which is explained according to Fig. 1. do. An image of the original 1 is formed on 0ODA by an imaging system 2, and all 0OD3 outputs and all gradation levels are digitized by an A/D converter 5. This data is buffered for several lines in the line memory 6 and outputted to the printing means, but since binary recording is the mainstream in conventional printing means, pseudo gradation expression must be performed using a dither pattern.

For this purpose, the signal is converted into a signal form required by printing hardware by the printer controller 8 and supplied to the print head 9 through the teaser pattern generator 71&:.

Due to the above signal flow, why does Book A7. In addition to requiring a high-speed converter 5, a line memory 6 with the number of gradation bits multiplied by the number of gradation bits, and a complicated printer controller 8, expensive parts including 0OD3 must be used.

Furthermore, the printing part requires a dot density of G17.16 dots/% or more in order to achieve both gradation and resolution, making it very expensive and at a speed that is not compatible with ordinary copying machines. A full color version was not possible.

〔the purpose〕

The present invention eliminates these drawbacks and has the following objects: (1) To realize a low-cost, ultra-compact print head for photocopying with excellent gradation reproducibility.

(2) To realize a high-speed full-color copying print head.

[Overview]

The copying print head of the present invention is equipped with a conversion chip in which an optical sensor array, a signal pulse width conversion means, and a driving means are formed on the same semiconductor chip, and a multi-printing means that can directly modulate dot gradation depending on the pulse width. has a substrate;
It is characterized in that the conversion chip and the substrate are electrically connected.

〔Example〕

The present invention will be explained below with reference to FIG. 2 and subsequent figures.

FIG. 2 shows the overall configuration, in which the conversion chip 10 is directly mounted on the substrate 11 mounted on the array 121 of the printing means.
Face-down mounting is performed through the contact pad 14. Reference numeral 13 denotes a generator and a controller for a comparison signal for pulse width conversion, etc., including a γ correction function.

Figure 3 shows an equivalent circuit. Figure 4 shows the timing chart.

The signal 32 generated by the optical sensor 20 is compared with the output 31 of the comparison signal generator 13 by the comparator 21, and the comparison is made so as to reset all the outputs 33 of the flip-flop 22, which have been set in advance by the set signal 30. The output 34 of the device 21 is output.

Therefore, the magnitude and pulse width of the output 32 of the optical sensor 20 are modulated. This ketotriper 23 drives the multi-printing means 24.

The shape of the comparison signal 51 supplied to the comparator 21 is not linear for the following reason. Since it is a copy, the image density of the printout must be linear in a 1:1 ratio with respect to the image density of the input (original) as shown in Figure 5.

However, once the saturation density is determined, the signal output of the optical sensor 20 has an output γ characteristic as shown in FIG. 6 for OII (image density), which is directly proportional to the blur rate. on the other hand,
The printing cap also has a T characteristic as shown in FIG. 7, for example, although the image density can be modulated by the pulse width. Since the T correction curve must be determined as a total of the two above, FIG. 8 shows the relationship between them.

The fourth quadrant shows the relationship between the input and output OD, the fourth quadrant shows the output characteristics of the optical sensor, and the fourth quadrant shows the output image density characteristics during pulses.
A gamma correction curve for converting into a full pulse of the optical sensor output, as shown in the quadrant, is determined. If the comparison signal output 31 is set and supplied in accordance with this supplementary IF curve, γ
Correction will also be realized.

Next, a printing method that can realize dot gradation modulation during pulses will be described.

First, the "electrification thermal transfer printing method" described in the claims will be described.

As shown in FIGS. 9A and 9B, this method includes a layer 40 that generates heat due to a common type, and a colored layer #4 whose Q viscosity decreases due to heat.
Using a transfer sheet 45 with 1, a full voltage is applied between the pin electrode 42 and the common electrode 43, and the paper 44
(46 in Figure 9B is the base material) This method can create a distribution of heat generation as shown in Figures 10A and B, so the threshold of transfer heat loss can be adjusted. 47 is quite steep, it is possible to modulate the area of the transferred dots by changing the applied energy. (a) is a cross-sectional view of the electrode, (b) F'1 calorific value distribution diagram, (
c) is a transcription dot diagram. Therefore, the printing characteristics of this method are
Binary me, screen line F! It can be said that this method is similar to the normal halftone printing method, in which the dot pitch is constant and all gradations are expressed by modulating the pit area. The curve shown in FIG. 7 described above is the printing γ characteristic of this method.

Although the applied energy can be changed by one voltage of lightning or by the voltage application time, it is preferable to keep the voltage constant and modulate only during pulses from the standpoint of thermal processing and compatibility with digital circuits.

Next, the "electrification transfer printing method" will be described.

This method was published in Japanese Patent Application No. 53-95547, “Electrification Recording Material”.
Using the recording method described in , it is possible to perform gradation recording by dot gradation modulation using a transfer sheet (If) as shown in FIG.

The transfer sheet 50 basically includes a conductive layer 51 with conductive anisotropy, a semiconductor layer 52, and a common electrode layer 53 for feedback. l
:When electricity is applied between the bottle 54 and the large-area common electrode 55, a breakdown occurs in a small area near the semiconductor layer 52 directly under the bottle 54, current flows, heat is generated, and the semiconductor r@52 containing carbon black is heated. It melts and scatters and is transferred onto the paper 56. Although Patent No. 53-95547 describes the image production as 1% by applied voltage, modulation is also possible during pulses. The reason why dot density gradation is applied in this method is that there are a large number of buses that cause breakdown in the minute area within the area of the bin 54, and the breakdown voltage and statistical delay time have a broad distribution. Therefore, as the number of minute dots increases, the modulation occurs depending on the size, and visually it appears as a sufficiently dense modulation.

(See Figure 12) S is the area of the bin electrode.

Next, we used a thermal head to create heat distribution.
This paper describes the thermal transfer printing method.

This method focuses on the difficulty of dot gradation modulation in normal thermal transfer printing methods, and applies the idea of the ``electrifying thermal transfer printing method'' mentioned above, which creates a heat distribution in the thermal head itself. So, is that an example? It is shown in FIG. The common electrode 60 is ring-shaped, and the drive type i61
By forming it so as to enclose it and filling the gap with the heating resistor 62, the current density distribution becomes smaller toward the outside, so that a heating distribution can be created. When this head is combined with a normal thermal transfer sheeter, a printing method capable of dot gradation modulation is obtained, similar to the ``electrification thermal transfer printing method'' described above. The details below are the same as those of "Electrical Thermal Transfer Printing Method", so please refer there.

Next, we will discuss the "thermal transfer printing method using dye sublimation". Since this method has been known for a long time, details can be found in the Journal of the Image Electronics Engineers of Japan Vol. 12, AI, ('83), PlB
Please refer to "sublimation transfer type pull color printer", etc., but if you use a dye that sublimates and diffuses when the temperature is raised as a coloring agent and prints with a thermal head using a thermal transfer method, dot density gradation can be applied.

This takes advantage of the diffusion rate of the dye, and the amount of dye transferred is proportional to the amount of time the dye is heated above the sublimation temperature.

Above, we have described four methods, but there are printing methods that can directly modulate dot gradation, including other methods.
The configuration of the present invention is such that the optical image input section has a 1:1 correspondence at the dot level and is extremely simple, including γ correction.

As in the conventional example, it is impossible to configure the present invention using a method such as a dither method that does not allow the number of printed dots to match the optical input partial resolution. Once all the data have been arranged, it is necessary to serially perform γ correction processing, dither processing, and then make it correspond to data for several dot lines of the printing device.

Therefore, it is clear that the configuration of the present invention is extremely simple.

Furthermore, it is clear that a full-color photographic image can be easily obtained by changing the color of the light waves and performing triple copying (preparing transfer sheets of all three colors).

Including the method described below, when obtaining a color image, the sensitive wavelength distribution of the input sensor, the γ characteristics of the transfer sheet, etc. may differ depending on the color, and in that case, the comparison signal 51 is calculated based on the T correction curve. You can deal with this by having more than one.

Next, considering the application to full color, an example of the configuration of the optical sensor 20 in the configuration of the present invention is shown in FIGS. 14 and 15. FIG. 14 shows an example in which an array of optical sensors 20 for six colors is prepared, and each array is provided with a different filter 71 in front of it, and the input to the signal pulse width conversion means 72 is changed to the switching means 7.
0, and the signals of each color are read without switching the light waves. In FIG. 15, there is one sensor in the array of optical sensors 20, but five of them are considered as one set, and a filter 71 of each color is provided. Similarly to the example shown in FIG. 14, the input to the signal pulse width converting means is switched by the switching means.

Examples of the present invention will be given below.

Example 1 - An IC incorporating 70 circuit blocks as shown in FIG. 16 was manufactured. The optical sensors 20 are 120μ×200μ, arranged at 200μ pitch, and 210 careys per 1 C. In order to perform generation time division driving, a selector 80 is provided, and comparators 81 and 1 are connected to each of the three optical sensors 20.
82.1 flip-flops, 8 driver selectors
3, 1 piece, driver 84, 6 pieces, pad 85, 6 pieces metal provided.

FIG. 17 shows the entire layout within 1C. In this embodiment, the pad layout is for face town mounting. The width of this chip is 1.5~
It is extremely long and thin with a length of 2.0 mm and a length fi of 42%.Since the chips are laid out continuously, the cutting accuracy of the guissing tool must be at a level of ±50μ. The comparison signal generation and controller section 86 is made outside the chip and is for supplying signals to the chip, and the details of the block are shown in FIG. 18. FIG. 19 shows details of the comparison signal generation section,
FIG. 20 is a timing chart.

The operation will be explained below.

The frequency of the clock 102t generated by the OK generating section 90 is divided, and the reset signal 103 is generated by the period timer 91.

The selector signal generating section 95 generates a 2-pit selector signal 104 by frequency-dividing the set signal 103Q14 and supplies it as a switching signal for the canopy drive. The comparison signal 105 is an integration time constant sound of a Miller integration circuit including an obeman amplifier 96, a capacitor 97, a jitter-resistance group 98, and a reference voltage source 99.
It is obtained by polygonal line approximation by switching the analog switch group 100. In order to determine the shape of the polygonal line of the comparison signal generator 94, an address counter 92 for counting the clock 102 and a ROM 95f containing data addressed by the output of the address counter 92 and determining opening/closing of the analog switch group 100 are used. There is. In this example, with 4 bits of output, there are 52 types of slope of the polygonal line.
I'm getting it.

The number of divisions in one period is 32. The Miller integration circuit switches the analog switch 10 by the set signal 103.
1, it is reset every cycle.

FIG. 21 shows the overall configuration, in which IIt electrodes 112 are formed with a thick film on a ceramic substrate 110 at a pitch of 200 μm.
, an IC chip 111 formed with an electrode width of 100μ?
, implemented face down.

113 is an external power supply.

Using the head manufactured in this way, the 22nd
When the copying machine was configured as shown in the figure, it was possible to copy one A4 sheet in 5 seconds with 32 gradations and 5 pixels per frame.

120 is a photo original, 121 is an original moving table, 122tff
A light source, 123if fiber lens array, 124 a head manufactured in this example, 125 a platen, 126 a sheet for electrical thermal transfer, and 127 a paper pass mark.

Embodiment 2 - The electrical connection between the IC chip 111 and the substrate 110 is
As shown in FIG. 3, a flexible tape 130 was used. In this case, there are advantages that vibrations of the head are not transmitted to the optical sensor section and that the positional relationship between the printing section and the optical sensor section can be freely selected.

Example 3 A part of the configuration shown in FIG. 22 of Example 1 was changed to make it full color. R2O and B filters were prepared in front of the light wave 122, and the filters were changed three times and copied. .

At that time, the transfer sheet 126 was printed in Y, M, and 05 colors, and was printed three times on the same paper.

Although the γ characteristics for each of the 1260 colors of the transfer sheet are the same, the wavelength sensitivity of the optical sensor for each R, G, and B, and the halogen lamp used as the gold light source 122, the energy supplied for each R, G, and B is Since they are different, the comparison signal 105'i
5 types were prepared on ROM95 and switched synchronously. As a result, it was confirmed that there is a possibility of color reproduction of at least 10,000 colors, and it was found that no false color was generated even in skin tones.

Embodiment 4 - A device having five rows of optical sensor sections as shown in FIG.
R, G, B filters for each row - I attached to the front of 71i
A test was conducted in the same manner as in Example 6 using the C chip 11 and a gold halogen lamp as the light source 22, and the same results were obtained.

Example 5 - When the optical sensor section having the configuration shown in FIG. 15 was used, the same results as in Example 4 were obtained. However, the pixel pitch has fallen to the lowest level.

Example 6 - The same printing unit as in Example 1 was used, and a transfer sheeter using the electrical transfer printing method as shown in FIG. 11 was used, and similar results were obtained. However, since the printing γ characteristics were different from those of Examples 1 to 5, a dedicated ROM 93 was required.

Example 7 - A thermal head having the structure shown in FIG. 13 was fabricated on a ceramic substrate at 5 dots/%, and the same procedures as Examples 1 to 5 were carried out.1. equivalent results were obtained.

However, the required power is several times larger than that in Example 1, and means for heat dissipation had to be added.

Example 8 - Using a normal thermal head, having the same configuration as Example 7,
Similar results were obtained using a dye sublimation type thermal transfer sheet. However, since the required energy was several times that of Example 7, it was necessary to reduce the printing speed due to thermal troubles.

〔effect〕

As described above, according to the present invention, a high-speed, low-cost tttAl copier and full-color copier can be realized with a simple configuration.

The reason for this is that the print head capable of dot gradation modulation and the optical sensor have a 1:1 correspondence and are highly integrated, which was necessary in the past. This is due to the fact that the high-density head, degassing, gamma correction processing, A-portion conversion impaqua, etc., such as the pixel density divided by the square of the number of gradations = dot density, have been made very simple for wood.

This feature is magnified many times over, especially when converted to full color.

[Brief explanation of drawings]

FIG. 1 shows an example of the configuration of a photocopying machine that does not use the conventional electrophotographic process. Figure 2 is an external view of the configuration of the present invention, where A is the overall view and B
is a sectional view. FIG. 3 shows an equivalent circuit diagram of the present invention, and FIG. 4 shows a timing chart. FIG. 5 shows an example of the %Ay% property achieved by the present invention, FIG. 6 shows the γ characteristic of the optical sensor, FIG. 7 shows an example of the 1% printing property of the printing device, and FIG. Combining the above w6 shows how the shape of the curve to be corrected should be determined. 9A and 9B are explanations of the principle of the electrical thermal transfer printing method, and FIGS. 10A and 10B are explanations of the method of modulation. Figure 11 is an explanation of the principle of energizing one transfer method, m12 diagrams A and B.
shows how the density gradation is applied using this method. FIGS. 13A and 13B show structural examples of a thermal head that forms a heat generation distribution. FIG. 14 and FIG. 15 show an example of the configuration of the optical sensor section according to the present invention that is compatible with colorization. FIGS. 16 and 17 show the isochoric circuit and layout of the IC chip used in the first embodiment. FIG. 18 shows the configuration of the comparison signal generation and controller section used in Example 1, FIG. 19 shows details of the comparison signal generation section, and FIG. 20 shows a timing chart. 21A and 21B show the overall configuration of the first embodiment, and FIG. 22 shows an example of the configuration of a copier system using the first embodiment. FIG. 23 shows the configuration of the second embodiment. 20 is an optical sensor, 26 is a signal pulse conversion means, 23 is a driving means, 25ri conversion chip, 12 is a multi-printing means, 11 is a substrate, 14 is an electrical connection part, and 71 is a filter. Applicant: Suwa Seikosha Co., Ltd. Figure 1 / 2 2L" 31st ゜ Begekenya 1 ma 1 person No. 71] 0υ ding OO 5 (4) Pa1゛□□ Ol, 5 (mouth) Shito Saiichi Masakata- 8 S 9 i,'+ [,2 17//・ Mayumi 1 5b-λ-2-- ---Figure 11 8 〇 Figure 12 Figure 13 Figure 14 z 15L! 1] 1: 1 ---111111------ 1st b 17th Figure 'l' 1 19th I Figure 21 Figure 20

Claims (1)

[Claims] (1) Optical sensor array, signal pulse width conversion means. It has a conversion chip in which the driving means is formed on the same semiconductor chip, and a board on which multi-printing means capable of direct dot gradation modulation according to the pulse width is mounted, and the conversion chip and the front station board are electrically connected. A print head for copying that is characterized by a f2) The copying print head according to claim 1, characterized in that the lithium signal pulse width conversion means performs nonlinear conversion. (3) The copying print head according to claim 1, wherein the multi-printing means capable of direct dot gradation modulation is an electrode array that performs current thermal transfer printing. (4) The multi-printing means capable of direct dot gradation modulation is a normal thermal head using a sublimation dye thermal transfer sheeter or a thermal head that forms a complete heat distribution distribution. Print head for copying. (5) The copying print head according to claim 1, wherein the substrate is made of ceramic, and the conversion chip is directly mounted on-chip in a face-down manner. (6) The copying print head according to claim 1, wherein the optical sensor array is composed of a plurality of rows, and each row is provided with a filter having a mutually different transmission wavelength distribution on its front surface. . (7) The above-mentioned optical sensor array is arranged in a row of five sensors, and filters with mutually different transmission wavelength distributions are regularly provided in front of the array.
Print head for copying as described in section. (8) The copying print head according to claim 2, wherein the signal pulse width conversion means has at least two or more types of conversion curves, and is switchable by an external command.