JPH0635192B2 - Recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a recording apparatus, and more specifically, a means for scanning a recording head having a plurality of recording elements arranged on a line in a direction perpendicular to the arrangement direction, and the head in the arrangement direction. To a recording device having means for relatively moving the same.

[Prior Art] In this type of conventional printing apparatus, first, a print head is scanned in a direction perpendicular to the array of printing elements to obtain a printing area having a width corresponding to the array length of the printing elements. Then, the head is stepped in the array direction of the recording elements by an amount corresponding to the array length, and the same operation as described above is repeated to obtain the next print area continuous with the print area obtained previously. As described above, such an operation is repeated.

In addition, as such a recording head, there are a recording head in which droplets are ejected from individual elements by an ink jet so as to be landed on a recording paper, and a thermal element for performing thermal recording is arranged.

Furthermore, there is also a recording apparatus in which a recording sheet is fed instead of stepping the recording head in the array direction of recording elements.

However, in these recording apparatuses, even if the recording paper is fed while the head is stepped, the feeding distance is likely to vary, and therefore, the width of the array length of the recording elements can be obtained first. In addition, the seam portion between the printed area and the subsequently obtained printed area and the mutually adjacent dots may overlap or be completely separated.

That is, FIG. 1 shows such a state as an example, in which the white circle is the preceding printing area 1A and the black circle is the following printing area 1B, and only the joint portion is shown. However, in this case, there is a gap between the front and rear printing areas 1A and 1B, and a linear white streak appears on the image due to such a gap. Further, although not shown, for example, black stripes are generated when they are extremely overlapped with each other, and in any case, the image quality is significantly impaired.

Even if you make various adjustments to such problems at the beginning,
Since the recording paper is misaligned on the way, the adjustment was lost, and there was no way to prevent it.

[Objective] In order to solve such a problem while paying attention to such a problem, the preceding printing area and the next printing area following the preceding printing area are moved when the printing head moves relative to the printing paper in the printing element row direction. In order to obtain a constant width of overlap with the print area of the recording medium, and to supply a selective signal to the recording element array so that mutual recording can be obtained in the recording of the overlapping area. An object of the present invention is to provide a recording apparatus that can obtain a high-quality image without any noise.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

In the following, an example using a liquid jet recording head will be described. For example, if the number of recording element arrays is 128
It is assumed that each has four heads arranged in parallel.

FIG. 2 (A) shows an example of a recording apparatus to which the present invention can be applied. In this example, such recording heads 2A, 2B, 2C and 2D are used.
By scanning the carriage 3 attached with the drive motor 4 in the X direction via the timing belt 5,
It is possible to obtain the print area 6 shown by hatching by scanning once.

Reference numeral 7 is a stepping motor that advances the head mounting base 8 in the Y direction together with the carriage 3 and its driving device.

Further, FIG. 2B is also an example of a recording apparatus to which the present invention can be applied. In the case of this example, the recording paper 1 wound on the roll 9 is moved by the stepping motor 7 in the Y direction. Paper is fed in increments of.

A case in which the present invention is applied to such a recording apparatus will be described below. As an example that can be easily understood, a recording element array for four colors of yellow, magenta, cyan, and black is used as a second example. A case will be described in which multiple printing is carried out by the apparatus shown in FIG. 3A so that mutually different complementary colors can be obtained at the joint portion.

Now, the mutual complement of one of these colors will be described with reference to FIG. 3, where A is the heads 2A to 2D when the carriage 3 is operated in the X direction in FIG. 2 (A). One of the heads is the length of the printing area 1N dot-printed on the recording paper 1, B is the length of the recording element array in the head 2, and C is 1 when the head mounting base 8 is stepped in the Y direction.
It is the step feed length.

The feed length C is made shorter than the length B of the recording element array, but how short the feed length C is set is suitable for complementing the color at the joint portion. The case where two lines of unevenness are formed by lines will be described. That is, the shaded area 11 in FIG. 3 shows the overlapping portion of these two dots, and by moving the head mounting base 8 by the feed length C which is shorter than the array length B by 2 dots, A partial overlapping area 11 is obtained.

Therefore, in such an overlapping area 11 of the recording, in order to mutually complement the recording at the joint between the printing areas 1A, 1B, 1C ... The uneven pattern shown in FIG. 4 is the third
The selection signal is obtained in the overlap area 11 shown in the figure.

Thus, by driving the recording element array in this way, the seams between the regions 1A and 1B as shown in FIG. 1 are mutually complemented as shown in FIG. Can be

FIG. 6 shows an example of the selection drive circuit necessary for obtaining the printing pattern shown in FIG. Here, D1 is an input line for introducing serial input data.

This serial input data is pixel data that is sequentially introduced in accordance with the scanning of the recording head (nozzle array) 2 in the X direction. That is, the serial data (128 pixels) that should be supplied to the recording head (nozzle array) 2 stopped at a predetermined position is first introduced, and then the recording head (nozzle array) 2 moves in the X direction 1 by the number of pixels. The serial data (128 pixels worth) to be supplied when stopped at that position is introduced. Similarly, serial data is sequentially introduced until the recording head (nozzle array) 2 reaches the end in the X direction.

C1 is a counter, which increments by 1 in response to the application of the clock signal and is reset to “0” in response to the application of the refresh signal (for example, transmitted every 2048 clocks (16 lines)). It Here, the clock signal means a signal transmitted from hardware (not shown) in synchronization with the serial input data.

C2 is a count, which receives a scan end signal sent when the print head (nozzle array) 2 reaches the end in the X direction (that is, when one scan ends), and counts the count value by one. Increment.

ROM-1 is a read-only memory that stores the tables shown in FIG. 7 (A) and FIG. 7 (B).
A 1-bit output signal is sent using the outputs of C1 and C2 as addresses.

INV is an inverter that inverts and outputs the logic level of the input signal, and G1 is an AND gate.

Next, the operation of the selective drive circuit shown in FIG. 6 will be described with reference to FIGS. 4 and 7 (A) and (B).

First, in the first printing process (I) shown in FIG.
The case where xn serial data are introduced will be described. In this case, since the scanning end signal has not been sent yet and the output of the counter C2 is "0", it is shown in FIG. 7 (A) according to the L address defined by the counter C1.
The output data shown in is obtained. Here, when the signal logic level output from ROM-1 is "0", the inverter IN
Since the signal of the logic level "1" is applied to the AND gate G1 via V, the serial input data is directly output via the AND gate G1. However, when the signal of the logic level "1" is output from the ROM-1, the AND gate G1 is closed, so that the corresponding bit of the serial input data is not output.

Thus, according to the example shown in FIG.
The image signals corresponding to the 7th dot and the 128th dot pass through the AND gate G1 as they are, but the image signals of the 127th dot and the 128th dot in the second column are blocked by the AND gate G1 and transmitted. There is no such thing. The same applies to the third to n-th columns. Thus, for the 126th dot and the 127th dot, the data to be printed is selected so as to form the unevenness shown in FIG.

In the first printing process (I), the printing boundary of the first dot (pixel row of the first row) is changed by passing all the data of the first dot to the 126th dot. Although the contents of ROM-1 (see Fig. 7 (A)) are set in advance so that they become straight lines, as in the second printing process (II) shown in Fig. 4, the boundary of the first dot is If the line does not have to be a straight line, the table shown in FIG. 7 (A) is unnecessary.

When the first printing process (I) is completed, the scanning end signal is supplied to the counter C2, and the counter value is incremented by 1. As a result, the table shown in FIG. 7 (B) is selected, and image formation is performed on the printing area having the unevenness as shown in FIG.

Similarly, the image formation after the third printing process (III) can be continuously performed.

By the data processing procedure described above, the seam portion (two dots in this embodiment) in each printing area is connected without a gap by repeating a certain concavo-convex pattern.

The serial input data described above can be obtained by sequentially accessing from an image data memory (not shown), or can be obtained from an image reading device equipped with a line sensor.

FIG. 8-1 is a circuit diagram showing another configuration example of the selection drive circuit. Unlike the circuit configuration shown in FIG. 6, the circuit configuration shown in this figure focuses on only the concavo-convex portion (two dots in this embodiment) that is the joint (seam) of each printing area, and It controls whether or not to be involved in formation. In other words, in the circuit shown in FIG. 6, it was determined whether or not to output all of the first dot to the 128th dot. However, since selective driving is required only for two dots where the seams overlap, It is only necessary to determine output stop dots for the two dots.

In FIG. 8-1, G2 is an AND gate, G3 is a NAND gate, and G4 is an OR gate. The first signal S1 input to the OR gate G4 is a pulse signal of logical level "1" which is generated only when the image signals corresponding to the first dot and the second dot are introduced as serial input data. . The second signal S2 input to the OR gate G4 is a pulse signal of logic level "1" which is generated only when the image signals corresponding to the 127th dot and the 128th dot are introduced as serial input data. is there.

C3 is a counter that is cleared in response to the refresh signal and increments by 1 in response to the output pulse of the OR gate G4.

C4 is a counter, which is incremented by 1 in response to a scan end signal sent every time the print head (nozzle array) scans in the X direction.

ROM-2 is a read-only memory that stores the tables shown in FIGS. 8A to 8C, and outputs a 1-bit output signal with the outputs of counts C3 and C4 as addresses. .

Next, referring to FIGS. 4 and 8-2 (A) to (C),
8-1 The operation of the figure is explained.

In the first printing process (I), the clock of the first and second dots and the first
The 127th and 128th dot clocks are input to the counter C3. As a result, the table shown in FIG. 8-2 (A) is referred to, and the address "000" (first dot), address "001" (second dot), address "002" (127th)
The output "0" is transmitted for all of the dot) and the address "003" (128th dot). Therefore, the AND gate G2 remains open, and the printing as shown in FIG. 4 is performed on the first column. The same applies to printing on the second and subsequent columns.

After that, when the counter C4 is incremented by 1 by the generation of the scanning end signal, the second printing process (II) is started,
The table shown in Fig. 8-2 (B) is selected according to the address of ROM-2. In this table, the address "040" (first dot in the first column) is output "1", address "042"
As is clear from the fact that the output (1st row, 2nd dot) is "1", it is possible to print 2 dots of pixels in duplicate in the boundary area of the 1st row. The output of serial output data has been stopped so that it will not occur.

The ROM-2 stores 16 columns (2048 bits) of the uneven pattern, and when one uneven pattern is completed during one scan in the X direction, a refresh signal is sent out, and this uneven pattern is repeated. .

When the count value of the counter C4 is incremented by 1 by the scanning end signal sent thereafter, the 8th-2 (C)
The table shown in (1) is selected, and a new concavo-convex pattern for avoiding duplicate marks is formed in the printing boundary area.

After that, the above-described printing process can be repeated to form an image with uneven seams.

FIG. 9 shows an image reading device for sending serial input data to be supplied to the above-mentioned selective drive circuit (see FIGS. 6 and 1-8), and image formation based on the serial input data. FIG. 1 is a schematic configuration diagram of an image processing apparatus that also includes a recording device. The present device is an example of a device that sequentially outputs read image data without including an image buffer memory. In the illustrated apparatus, a lens 12 is used to form an original image on the reading element array 13, and image data is sequentially read from the reading element array 13 and is fed stepwise in a direction indicated by an arrow 15 (constant). (Movement at every interval).

Then, the read image data is supplied to the recording head (nozzle array) 2 to form an image again. However, it is necessary to provide a selection driving circuit (not shown) (see FIGS. 6 and 8-1) in front of the recording head (nozzle array) 2 to perform the above-described signal processing.

In the above, in the case of multiple printing, an example in which drive scanning is performed so that mutual complementation is obtained at each seam for each color has been described, but an independent selection drive circuit is provided for each nozzle array. Needless to say, it is possible to change the complementary pattern for each color.

In this case, full-color printing is performed, but there is a chance that a portion where all four colors overlap or a portion where all four colors are not printed and remain in the other color of the recording paper may occur due to some misalignment of the seam. Since the number is small, even if the step feed distance B is too long or too short, a sharp change in the shade at the joint is inconspicuous.

By the way, in the case of magenta color complementation as an example, it is generally known that when magenta color complementation is performed on cyan, the comparison between when the back of the recording paper is white and when it is cyan. It's about to come.

[Effects] As described above, according to the present invention, a plurality of recording heads each having a plurality of recording elements for forming dots are provided, the plurality of recording heads are relatively scanned with respect to the recording medium, and the recording is completed by one scanning. After that, the recording medium is relatively fed to the plurality of recording heads in a direction orthogonal to the relative scanning direction so that the previous recording area and the next recording area are overlapped by at least one dot to connect the recording areas. In the printing apparatus that prints with the above method, the overlapping area is printed based on a predetermined pattern that is configured by the conversion table so that the printing states by the previous scanning and the next scanning are complementary, so that the preceding printing is performed. It is possible to prevent deterioration of the image quality due to blank printing or overlapping patterns at the joint between the area and the next-row recording area. When the recording element arrays are arranged and recording is performed with different colors for each element array, there is an effect of making the above-mentioned drawbacks occurring at the joint portion more inconspicuous. It can be prominent at the time of printing.

[Brief description of drawings]

FIG. 1 is a model diagram showing an example in which a blank line is generated between the preceding printing area and the next line printing area during recording by the conventional recording device, and FIGS. 2 (A) and 2 (B) are Possible application of the present invention 2
FIG. 3 is a perspective view showing the configuration of each type of recording device, FIG. 3 is a model diagram showing as an example the overlapping state of the printing areas obtained by the present invention, and FIG. 4 is the mutual complementing of the printing in the overlapping state. FIG. 5 is a model diagram showing an example of a recording state when a signal as described above is sent, FIG. 5 is a model diagram showing an example of a blurring state of a printing area overlapping portion obtained by the recording device of the present invention, and FIG. FIG. 7 is a configuration diagram of a selection drive signal generating circuit applied to the present invention, FIGS. 7 (A) and 7 (B) are views showing an example of a table stored in the selection drive ROM, and FIG. 8-1 is the present invention. FIG. 8-2 is a configuration diagram showing another example of the selection drive signal generating circuit applied to FIG. 8, and FIGS. 8-2 (A) to (C) are views showing one example of the table stored in the selection drive ROM of FIG. 8-1. FIG. 9 is a perspective view showing an example of a recording apparatus of still another form to which the present invention can be applied. It is a figure. 1A, 1B, ..., 1N ...... Printing area, 2,2A, 2B, 2C, 2D ...... Recording head, 3 ...... Carriage, 4 ...... Drive motor, 5 ...... Timing belt, 6 ...... Printing area , 7 ...... Stepping motor, 8 …… Mounting board, 9 …… Roll paper, 11 …… Overlap area, C1, C2, C3, C4 …… Counter, ROM1, ROM2 …… Storage device, 12 …… Lens, 13 ...... Read element array.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location G06F 3/12 H H04N 1/23 Z 9186-5C 8703-2C B41J 3/12 C 8703-2C L

Claims (4)

[Claims] 1. A plurality of recording heads each having a plurality of recording elements for forming dots, the plurality of recording heads are relatively scanned with respect to a recording medium, and after the recording by one scanning is completed, the recording head is orthogonal to the relative scanning direction. In the recording apparatus, the recording medium is relatively fed to the plurality of recording heads in the direction so that the previous recording area and the next recording area are overlapped by at least one dot, and the recording areas are connected to each other to perform recording. The printing device is characterized in that the area to be printed is printed based on a predetermined pattern configured such that the printing states by the previous scanning and the next scanning are complementary by the conversion table. 2. The recording apparatus according to claim 1, wherein the plurality of recording heads respectively record different colors. 3. The recording apparatus according to claim 2, wherein the predetermined pattern is different for each recording head. 4. The recording apparatus according to claim 1, wherein the recording head is a nozzle array.