JPH07276774A - Pattern forming method and pattern member - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a novel pattern forming method when forming a pattern using recording materials of a plurality of different color components. A pattern forming method for forming a pattern using recording materials of a plurality of different color components, wherein a recording material of three primary colors of an additive method is used as the recording material of the plurality of color components. In particular, the recording materials of the three primary colors of the additive color method are made of red, green, and blue inks, and are patterned so as not to overlap each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pattern forming method for forming a pattern using recording materials having a plurality of different color components.

[0002]

2. Description of the Related Art Conventionally, for example, JP-A-56-8266 is used.
As disclosed in Japanese Utility Model Publication No. 56-79339, there is known a technique for forming a color image using three primary color inks of the magenta, yellow, and cyan subtractive color method or four color inks in which black ink is added. Has been.

[0003]

However, conventionally, since the ink of the subtractive color method as described above is used, there is a limit to the color limit range that can be expressed.

Therefore, an object of the present invention is to provide a novel pattern forming method for forming a pattern using recording materials having a plurality of different color components.

[0005]

In order to solve the above problems, the pattern forming method of the present invention is a pattern forming method for forming a pattern using recording materials having a plurality of different color components. As a recording material of a plurality of color components, a recording material of three primary colors of the additive color method is used.

[0006]

First, a color reproducing method according to an embodiment of the present invention will be described.

FIG. 1 shows a chromaticity diagram based on the well-known XYZ color system. In the figure, 1 is a range of existing colors, 2 is a range of colors that can be reproduced by the color-addition method, and 3 is a range of colors that can be reproduced by the subtractive color method. In addition, R, G, and B are points respectively corresponding to the three primary colors of the additive method, red, green, and blue.

As is apparent from FIG. 1, the additive color method enables color reproduction in a wider range than the subtractive color method. The relationship shown in FIG. 1 varies somewhat depending on the selection of the three primary colors. The reason why the color reproduction range of the subtractive method is narrow is that there is currently no ideal dye for the subtractive method.

Further, in the color reproduction by the subtractive color method, in order to reproduce a desired color, the patterns corresponding to the three primary colors or each of the three primary colors and black may be overlapped by a maximum of three or four plates. Moire may occur in the image.

Therefore, in the embodiment of the present invention, a color reproduction having a halftone is performed by using a color-addition method according to the density of the color points per desired unit area, that is, the distribution state of the color points.

Now, taking the unit area as an example, as shown in FIG.
A case will be described in which three dots are arranged in a matrix of 3 and have no overlap, and color reproduction is performed using a fluorescent substance that emits light of a predetermined color by irradiation of ultraviolet rays and general black ink. Here, in the case of reproducing red with high brightness and low saturation, 7 out of 9 dots are recorded with a phosphor that emits white, and the remaining 2 are recorded with a phosphor that emits red. When reproducing highly saturated red, all nine should be red. In case of reproducing yellow, approximately the same number of green and red is assigned to any of 9 dots. Then, in the case of high lightness yellow, some dots are recorded in white, and in the case of low lightness yellow, some dots are recorded in black. In addition, a plurality of color components are not overlapped on the same dot.

As described above, the unit area is considered as one pixel based on the distribution of the color components recorded in the unit area and the distribution thereof, and the color reproduction of one pixel is performed.

FIG. 3 shows a red component at a certain point of an original image obtained by color separation means using a well-known filter, a spectral member, etc.
An example of the intensity distribution of the green component and the blue component is shown. Note that FIG. 2 is normalized so that the maximum value of the intensity n of each obtained component is "3".

The color component obtained as shown in FIG. 3 (blue component n _B =
4/3, green component n _G = 2/3, red component n _R = 5/3) will be described as an example of processing in the case of color reproduction. First, 3
The minimum value of the intensity n of the component is detected. In this case, the intensity n _G (= 2/3) of the green component is detected. Then, a value obtained by multiplying the minimum value by 3, that is, "2" is white when the color is reproduced. Next, the shaded portion in FIG. 2, that is, the whole "9"
The difference between the value obtained by subtracting the value of each component from and the value obtained by doubling each component obtained by subtracting the minimum value is black when the color is reproduced. Further, three times the difference between the intensity n of each color component and the minimum value of the intensity n corresponds to the ratio of each color during color reproduction. That is, FIG.
In the example, red is “3”, green is “0”, blue is “2”, white is “2”, and black is “2”.

The five values thus obtained are 9 in FIG. 2, the ratio of the number of dots of each color occupying the dots. Then, according to the obtained dot number, dots of each color are assigned to 9 dots within the unit area. Incidentally, there is a case where a negative value appears in the calculation, and it is necessary to perform further color correction for this, but the description is omitted here. In this case, if the dots of the same color are made as close to each other as possible, halftone and color reproduction can be performed well. FIG. 4 shows an example thereof.

FIG. 5 is a schematic cross-sectional view of the structure of a reading section R capable of color separation of an original image according to an embodiment of the input means of the present invention. A document table GD made of glass or the like is formed above the reading unit R, and the user places a document to be copied on the document table GD. Below the document table GD, rod-shaped light sources Ll and L2 such as a fluorescent lamp for illuminating a document are provided, and light emitted from the light sources Ll and L2 is effectively document platen GD.
Reflector RM provided to illuminate the surface of the original placed on
1, RM2, a first plane mirror axis 1 for scanning (sub-scanning) a document, a second plane mirror axis 2, optical lenses OPL for forming an optical image of the document surface, and red and green components from light passing through OPL. , A spectral member DP for extracting the blue component, a spectral member D
A one-dimensional CCD (Charge Coupled) for reading the intensity of each light separated into three colors by P
Device) Image sensor CCDl, CCD2, C
CD3 is provided.

The light sources Ll, L2, the reflecting mirrors RMl, RM2 and the first plane mirror PM1 are integrated by a support ST and are fixed to the carriage CA1. The carriage CA1 moves forward on the guide rail GL from the left to the right (F direction) in the figure and moves back from the right to the left by well-known driving means.

The second plane mirror PM2 is the first plane mirror PM1.
The carriage CA2 moves on the guide rail GL in the same direction as the moving speed of the first plane mirror PM1 at half the speed. At the end of the forward movement, the plane mirrors PM1 and PM2 move to positions PM1 'and PM2' shown by dotted lines in the figure.
At this time, the optical path length from the document table GD through the plane mirrors PM1 and PM2 to the lens OPL is always kept constant.

The main scanning directions of the image sensors CCDl, CCD2 and CCD3 are vertical to the drawing, and the distances from the lens OPL to the three image sensors are all equal. During the forward movement of the plane mirrors PM1 and PM2,
If the signals from the light receiving elements of the image sensors CCDl, CCD2 and CCD3 are read out in sequence, the sequential signals obtained by raster scanning the document surface are used as image sensor CCDs.
It is possible to obtain a red component from 1 and a green component from the image sensor CCD 2 and a blue component from the image sensor CCD 3.

FIG. 6 is a schematic cross-sectional view of the construction of a recording portion P capable of multicolor recording according to an embodiment of the present invention. The recording portion P performs dot recording on a recording material such as paper using fluorescent ink and general black ink that emit red, green, blue and white light by irradiation with ultraviolet rays, and the addition method is performed by this. The color reproduction used is performed.

In the illustrated construction, PM is a recording material and Rl
Is a conveyance roller that holds the recording material PM that moves at a predetermined speed in the direction of the arrow Y and rotates in one direction, and MOT1 is a conveyance motor that drives the conveyance roller Rl. Also, R
Reference numerals 2 and R3 denote intermediate rollers, which follow the movement of the recording material PM, change the traveling direction of the recording material, and impart flatness to the recording material PM for recording operation. R4 is a tension roller for sandwiching the recording material PM so as to give tension to the recording material shaft.

(Explanation of an embodiment of the recording method of the present invention) PH is a recording head and is provided with fifteen ink ejection ports, which are opposed to the recording material PM at a predetermined interval, as shown in FIG. It has a unit JUT. In Figure 7, J
R is a red ink, JG is a green ink, JB is a blue ink, JW is a white ink, and JK is a black ink ejection port, and a recording operation is performed when moving in the direction of arrow S in the figure. That is, three outlets are provided in the vertical direction in the figure, in which the outlets for the fluorescent inks of red, green, blue, and white and the outlets for the black ink are arranged in a line from left to right in the figure. The suffix "1" is attached to the emission port of the first stage from the top of the drawing, the suffix "2" is assigned to the second stage, and the suffix "3" is assigned to the third stage.

In this way, the recording heads PH are red, green,
Since a plurality of ejection openings are provided for each of blue, white, and black colors, it is possible to increase the recording amount by one recording operation, and high-speed recording becomes possible.

Further, since the above-mentioned ejection ports are integrally formed, the accuracy of the recording position adjustment for each color is improved, and the recording means can be downsized. It is possible to form an image having a good color balance, since the variation in the characteristics of 1 is reduced.

Returning to FIG. 1T is an ink tank containing the above-mentioned five colors of ink, 1P is a pipe for supplying the ink in the ink tank 1T to the recording head PH, and CV is a recording head for outputting a drive signal to eject ink from the above-mentioned 15 emission ports. A cable is supplied to the PH, CT is a connection terminal portion of the cable, MOT2 is a head moving motor that reciprocates the recording head PH in the direction of arrow X at a predetermined speed,
The recording head PH scans in the X direction as the head moving motor MO2 rotates the screen SC.

In this embodiment, the recording operation is performed when the recording head moves to the right in the figure, and when the recording head PH reaches the right end of the recording material, the head moving motor MOT2 reverses to show the recording head PH. Move it to the left and return to the recording start position.

The movement of the recording head PH is synchronized with the ink ejection timing from the ejection port, and the recording head PH is set to 1 so that the dots ejected from the same ejection port and recorded on the recording material PM do not overlap. Ink is ejected every time the dot is moved. Also, record head PH 1
Dot recording for 3 lines is performed by scanning, and the movement of the recording material in the Y direction by the transport roller Rl is performed by the recording head PH.
At the end of the forward movement, a distance of 3 dots will be performed. The recording time is shortened by moving the recording material PM in the Y direction when the recording head PH is returned.

FIG. 8 is a block diagram showing an example of a circuit configuration for color reproduction operation according to the present invention, using the reading section R shown in FIG. 5 and the recording section P shown in FIG.

Reference numerals 500, 501, and 502 denote the image sensors CCDl, CCD2, and CCD3 shown in FIG. 5, respectively. Reference numerals 503, 504, and 505 denote analog digital (A / A / A / D) for converting an analog signal into a digital value of a predetermined bit.
D) A converter. The analog image signal of the red component output from the image sensor 500 is converted into a digital image signal n _R of the red component by the A / D converter 503. Similarly, the analog image signal of the green component output from the image sensor 501 and the analog image signal of the blue component output from the image sensor 502 are also respectively input to the A / D converters 504 and 505 by the digital image signals n _{G of} the green component. It is converted into a blue component digital image signal n _B.

Digital image signals n _R , n _G , and n _B corresponding to the red, green, and blue color components output from the A / D converters 503, 504, and 505 are input to the minimum detection circuit 509. The minimum value Min of is detected. The detected minimum value Min is tripled by the multiplication circuit 510. The output of the multiplication circuit 510 becomes the white component digital image signal Nw.

The outputs n _R , n _G , and n _B of the A / D converters 503, 504, and 505 are also input to the adder circuit 511, and their sum Σn (Σn = n _R + n _G + n _B ) is obtained.
The sum Σn obtained by the adder circuit 511 is the subtraction circuit 512.
Entered in. The subtraction circuit 512 subtracts the sum Σn from “9”. The output of the subtraction circuit 512 becomes a black component digital image signal n _K and is input to the subtraction circuit 524.

On the other hand, A / D converters 503, 504, 50
The outputs n _R , n _G , and n _B of 5 are subtraction circuits 506 and 506, respectively.
It is also input to 507 and 508. Subtraction circuits 506 and 50
The output Min of the minimum value detection circuit 509 is input to 7, 508, and this value Min and the A / D converters 503, 5 are input.
The difference between the outputs n _R , n _G , and n _{B of} 04 and 505 is obtained. The value obtained by the subtraction circuit 506 is multiplied by 3 at the multiplication circuit 519, and the digital image forming signal N of the red component is multiplied.
_R , the value obtained by the subtraction circuit 507 is multiplied by 3 in the multiplication circuit 520 and the green component digital image forming signal N _G , and the value obtained by the subtraction circuit 508 is multiplied by 3 in the multiplication circuit 521 and the blue component digital image formation is performed. The signal becomes N _B.

The outputs of the subtraction circuits 506, 507 and 508 are input to the addition circuit 522, the sum of them is obtained, and the multiplication circuit 523 doubles the sum.

The output of the multiplication circuit 523 is input to the subtraction circuit and the difference from the output of the subtraction circuit 512 is obtained. This difference becomes the digital image forming signal N _{K of the} black component.

The red, green, blue, white, obtained as above,
Digital image forming signals N _R , N _G , N of each color component of black
_B , N _W , and N _K are input to the first memory circuit 513.
As described above, the value of this digital image forming signal indicates the number of dots of each color to be recorded per unit area.

Numeral 514 is a dot arrangement determining circuit which determines in what color nine dots in a unit area should be recorded by the value of the digital image forming signal stored in the first memory circuit 513 as follows.

That is, each color component is allocated in the order of the numerical values shown in the dots in FIG. 9 by the number of digital image forming signal values corresponding to each color component stored in the first memory circuit 513. For example, when the values of the respective digital image forming signals are N _R = 3, N _B = 2, N _W = 2, and N _K = 2 as in the above example, the dots 1, 2, and 3 in FIG. Like dots 4 and 5 are blue, dots 6 and 7 are white, dots 8 and 9 are black,
In this case, there is no green component, but dots are assigned in the order of red → green → blue → white → black. The order is not limited to this, and a preferable order is appropriately used for color reproduction and halftone reproduction. As described above, according to the value of the digital image forming signal stored in the first memory circuit 513, some point in the unit area is assigned according to the color reproduced by each point of each color.

Here, each color is represented by a 3-bit binary number. That is, red is 001, edge is 010, blue is 011, white is 100, and black is 101. Therefore, in the above-mentioned example, 001 corresponds to the dots 1, 2 and 3 of FIG. 9, 011 corresponds to the dots 4 and 5, 100 corresponds to the dots 6 and 7, and 101 corresponds to the dots 8 and 9.

A second memory circuit 515 is a memory capable of storing the dot array for each unit area determined by the dot array determining circuit 514 for the image signal for one scan of the recording head PH in FIG. For example, if the size of the unit area composed of 9 dots is 0.5 _mm x 0.5 _mm , the recording head HP is A
Assuming that the short side direction of the 4 size recording material is scanned,
Recording of 1260 dots per line is simultaneously performed for three lines by one scanning. Therefore, the second memory circuit 515
Stores 3780-dot color information. Since the color information is represented by the above 3 bits, the number of bits is 113.
It has a storage capacity of 40 bits or more.

Reference numerals 516, 517 and 510 are print heads HP.
Is a drive circuit for driving the recording head HP, which is shown in FIG. 7 and has upper exits JRl, JG1, JB1, JW1,
JKl is the drive circuit 516, and the middle exit port JR2
JG2, JB2, JW2 and JK2 are drive circuits 517
And the lower exits JR3, JG3, JB3, JW3, J
K3 is driven by the drive circuit 518, respectively.

The drive circuit 516 has three dots (dot 5.7.3) in the upper stage of the dot arrangement shown in FIG. 9, the drive circuit 517 has three dots in the middle stage (dot 2.9.6), and the drive circuit 518 has three dots. Lower 3 dots (dot 8.4.
The 3-bit signal representing the color information corresponding to 1) is repeatedly input from the second memory circuit 515. That is,
The 3-bit signal corresponding to dot 5.2.8 is simultaneously applied to the respective drive circuits 516, 517 and 518, and then the 3-bit signal corresponding to dot 7.9.4 is applied simultaneously to the respective drive circuits, and then to the respective drive circuits. A 3-bit signal corresponding to dot 3.6.1 is simultaneously input to each drive circuit. After the 3-bit signal corresponding to the dot 3.6.1, the dot 5. containing the color information of the next unit area again.
A 3-bit signal corresponding to 2.8 is input. As described above, in the case of the above-described A4 size, one scanning is repeated 420 times.

The input timing of the 3-bit signal is synchronized with the movement timing of the recording head HP for one dot in the X direction.

FIG. 10 is a detailed circuit diagram of the drive circuit 516 of FIG. The other two drive circuits 517 and 518
Since they have the same configuration, the description will be omitted.

SR1, SR2, and SR3 are 5-bit serial-in / parallel-out shift registers to which the 3-bit signal of the second memory circuit 515 is input for each bit. The recording head P provided in the recording unit P of this embodiment
Since the outlets for the five different colors of H are arranged in the scanning direction, the recording operation is performed when the head for emitting the color corresponding to the input 3-bit signal reaches a predetermined position. The shift register is for delaying the input signal. Al, A2, A3, A4 and A5 are AND circuits, and the terminals marked with a circle on the input side are inverting input terminals, and the output becomes high level when a 3-bit signal indicating that color is input. HR, HG, HB, HW, HK
Are the outlets JRl, JG1, JBl, JWl, J respectively.
It is an ejection head for ejecting ink from Kl and operates by a high level input from the AND circuit.

I1, I2 and I3 are shift registers SR
Input lines to 1, SR2 and SR3 are input to the input lines I1, I2 and I3 one bit at a time in order from the lowest of the three bit signals indicating the color to be recorded.

For example, a case where one dot is recorded in the order of green, white, red and green will be described with reference to FIG. Five dots HR, HG, HB, HW, and HK indicate the recording positions by the respective emission heads. In FIG. 11, a to d indicate the passage of time, and the recording head HP moves in the X direction on the same line. Also,
1 indicates the left end of the recording material. First, in a, the second memory 5
When 15 outputs a 3-bit signal 010 indicating green, the output of the shift register SRl to the AND circuit Al is 0, the output of the shift register SR2 to the AND circuit Al is 1, and the output of the shift register SR3 to the AND circuit A3. The output becomes 0. The AND circuit Al receives the red signal only, that is, the state of the input line from the top is 1. 0.
Since it goes high only when 0, the output goes low at this time. Therefore, the red emission head H
R does not work. Also, the other four emission heads do not operate.

Next, as shown in b, the recording head PH is moved in the X direction by a distance corresponding to one dot, and a three-bit signal 10 indicating white is displayed.
When 0 is input, a 3-bit signal indicating white is input to the AND circuit Al, and a 3-bit signal indicating green is input to the AND circuit A2. Accordingly, only the AND circuit A2 for ejecting the green ink becomes high level, and the ejection head HG indicated by the diagonal line operates to eject.

When the recording head PH moves again by a distance of one dot as shown by c and a 3-bit signal 00l indicating red is input, a 3-bit signal indicating red is input to the AND circuit Al to the AND circuit A2. The 3-bit signal indicating white and the 3-bit signal indicating green are input to the AND circuit A3. Therefore, only the AND circuit Al for ejecting the red ink becomes high level, and the ejection head H indicated by the shaded area.
R emits.

Further, when the recording head PH moves a distance of 1 dot as shown by d and a 3-bit signal 010 indicating green is input, the AND circuit Al is green, A2 is red, A3 is white. A signal indicating red is input to A4, but all the AND circuits are at a low level, and there is no emission head for emission operation.

Further, when the recording head PH moves a distance of 1 dot and a new 3-bit signal is input as shown by e,
A signal indicating green is input to the AND circuit A2, red is input to A, white is input to A4, and red is input to A5, and the outputs of the AND circuits A2 and A4 become high level. Therefore, the emission head H shown by the diagonal lines
G and HW perform the emitting operation.

Thus, from the left end of the recording material to the right, green, white,
Red and green dots are recorded continuously and without overlapping.

The output heads of the middle stage and the lower stage similarly perform the output operation based on the input 3-bit signal.

As described above, when the 3-bit signal indicating the color information input to the shift register is shifted to the position of the emission head of the corresponding color, the output of the AND circuit is set to the high level. In this case, the recording head HP is also moved in the X direction by one dot size as described above, and as a result, the dots of a predetermined color are transferred to the other dots at the dot positions determined by the dot array determination circuit 514. It is recorded without overlapping.

When the recording material thus recorded is irradiated with ultraviolet rays, each dot recorded with the fluorescent ink emits light of its own color as described above. Therefore, color reproduction by the additive method is performed.

In this embodiment, the unit area is constituted by 9 dots arranged in a 3 × 3 matrix, but the present invention is not limited to this, and can be realized by a matrix of 4 × 4, 5 × 5, etc. Further, by increasing the number of color points forming the unit area, it is possible to further widen the color reproduction range by the addition method.

Further, although the recording apparatus using the fluorescent ink has been described in the present embodiment, the present invention has a wider range of ink selection, for example, general dyes and pigments for printing, and dyes used for transmission type printing. Etc. are naturally applicable. At this time, when a white recording material is used, it is not necessary to perform a recording operation using white ink.

Further, as a recording apparatus to which the present invention can be applied, an electrophotographic system, a thermal transfer system, an ink jet system and the like can be mentioned.

Further, the present invention can be applied not only to a signal obtained by reading an original image but also to an image reproduction based on an image signal transmitted in space and an image signal read from a storage medium such as a magnetic disk or tape. Also, the color of the recording ink is 3
If a color other than the primary color is used, the color and gradation to be reproduced can be adjusted more preferably.

[0059]

According to the present invention described above, it is possible to provide a novel pattern forming method for forming a pattern using recording materials having a plurality of different color components.

[Brief description of drawings]

FIG. 1 is a chromaticity diagram based on an XYZ color system.

FIG. 2 is a schematic explanatory view of the present invention.

FIG. 3 is a diagram showing an intensity distribution of color components.

FIG. 4 is a diagram showing an example of color reproduction according to the present invention.

FIG. 5 is a cross-sectional view of a reading unit capable of color-separating a document image.

FIG. 6 is a sectional view of a recording unit capable of multicolor recording.

FIG. 7 is an enlarged view of a recording head

FIG. 8 is a circuit block diagram showing a circuit configuration for color reproduction operation according to the present invention.

FIG. 9 is an explanatory diagram of dot arrangement determination.

FIG. 10 is a detailed circuit diagram of a drive circuit.

FIG. 11 is an explanatory diagram of a recording operation.

[Explanation of symbols]

 CCD1, CCD2, CCD3 Image sensor DP Spectral member PM Recording material PH Recording head 509 Minimum value detection circuit 511 Addition circuit 514 Dot array determination circuit SRl, SR2, SR3 Shift register

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[Procedure amendment]

[Submission date] March 15, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Change

[Correction content]

Patent application title: Pattern forming method and pattern member

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction content]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pattern forming method for forming a pattern using inks of a plurality of different color components and a pattern member obtained by the method.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

[0005]

In order to solve the above problems, the pattern forming method of the present invention is a pattern forming method for forming a pattern by using inks of a plurality of different color components. The ink of the three primary colors of the additive method is used as the color component ink. Further, the present invention is a pattern member which is colored by the color components of the three primary colors of the additive method so as not to overlap each other.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0059

[Correction method] Change

[Correction content]

[0059]

According to the present invention described above, it is possible to provide a novel pattern forming method for forming a pattern using inks of a plurality of different color components, and a pattern member obtained thereby. .

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Claims (3)

[Claims] 1. A pattern forming method for forming a pattern using recording materials of a plurality of different color components, wherein a recording material of three primary colors of an additive method is used as the recording material of the plurality of color components. Recording method characterized by. 2. The recording method according to claim 1, wherein the recording materials of the three primary colors of the additive color method are red, green, and blue inks. 3. The recording method according to claim 1, wherein the patterns of the recording materials of the three primary colors of the additive color method are formed so as not to overlap each other.