JP2006281104A - Multi-gradation method of ink jet discharge data for ink jet coater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce various color filters by an ink jet coater without increasing the cost by enabling the coater to carry out multi-gradation jetting without increasing the number of hitting. <P>SOLUTION: At the time of transferring discharge date to an ink jet head of an ink jet coater, the gradation value including 0 and corresponding to the number of jetting grades, which is jetting data, is computed in multi-gradation in the direction of increasing the number of the jetting gradation by a computation circuit in the ink jet head side based on the data for altering the gradation value of the discharge data parameter containing the data and the multi-gradation discharge data is transferred to the ink jet head. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet discharge data multi-gradation method of an ink jet coating machine used for manufacturing a film-based color filter or a glass-based color filter.

Conventionally, when recording using a multi-drop type inkjet printer that sequentially discharges and records with a piezoelectric element in the nozzle, a predetermined amount of ink is ejected from the nozzle of the inkjet head, and the ejection operation is performed multiple times. Ink supply amount was controlled (Patent Documents 1 and 2).
JP 2003-145805 A JP 2004-174849 A

  In the above-described multidrop inkjet head, the number of operations for performing the ejection operation can be set within a predetermined number of gradations. Therefore, in order to increase the ink discharge amount from the settable range, the same inkjet heads are connected in layers and the ink is discharged at the same position, and the number of gradations that can be discharged from one head There is a method of increasing the amount of ink that can be discharged.

  However, when the same ink jet heads are stacked and connected, the number of heads used increases, and therefore the number of maintenance increases and productivity decreases. In addition, the cost of the entire system increases.

Therefore, in order to increase the number of gradations that can be ejected from the head, the number of bits must be increased. When the number of bits is increased, in the case of serial transmission, the number of bits in one group for transmitting data is approximately the number of bits in the shared wave mode.
As shown in this, as the number of bits increases, the data transfer speed decreases. Further, since the shortest time until the next discharge can be extended, the tact time increases (see FIG. 4).

  On the other hand, in the case of parallel transfer, unlike serial transfer, the transfer rate is not slowed, and the shortest time until ejection can be performed does not increase. However, since the number of signal lines corresponding to the number of bits must be increased, the circuit scale increases, the head unit price increases, and eventually the system cost increases.

  The above points will be described with reference to FIGS. As shown in FIG. 1, the share wave mode inkjet head 1 is an inkjet head that repeatedly discharges the A, B, and C rows sequentially.

  A simple operation flow until the ink jet head discharges is shown in FIG. The flow first receives data (discharge data and the number of discharge gradations) for discharging from the inkjet head, and transfers the data to the A-phase line buffer. Based on the transferred data, ejection is started from the A-phase nozzle. Simultaneously with the start of discharge from the A-phase nozzle, data for discharge is transferred from the A-phase line buffer to the B-phase line buffer. After completion of ejection from the A-phase nozzle, ejection is started based on the data transferred to the B-phase nozzle. Simultaneously with the start of ejection from the B-phase nozzle, data for ejection is transferred from the B-phase line buffer to the C-phase line buffer. After the completion of ejection from the B-phase nozzle, ejection is started based on the data transferred to the C-phase nozzle. Further, simultaneously with the start of ejection from the C-phase nozzle, data for ejection is transferred to the A-phase line buffer. After the completion of ejection from the C-phase nozzle, it is determined whether or not line ejection has been performed a set number of times by the line counter, and ejection is started based on the data transferred to the A-phase nozzle. Thereafter, the above-described operation is repeated for the number of lines to create an image.

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In the ink jet head having such an operation flow, when it is desired to increase the number of gradations and eject the ink, the data transfer speed becomes slow if the number of bits is increased. Further, when parallel transmission is used, there is a problem that the circuit scale increases and the system cost increases.
In view of the above circumstances, an object of the present invention is to manufacture various color filters using an inkjet coating machine that does not increase the cost, with the object of enabling ejection with multiple gradations without increasing the number of bits. Objective.

  The present invention has been made in consideration of the above problems, and when transferring ejection data to an inkjet head of an inkjet coating machine, a gradation value including 0 corresponding to the number of ejection gradations, which is ejection data, is represented on the floor. Based on the data of the ejection data parameter having data for changing the tone value, the arithmetic circuit on the ink jet head side calculates in the direction of increasing the number of ejection gradations, thereby increasing the number of gradations. An object of the present invention is to solve the above-mentioned problems by providing an ink jet discharge data multi-gradation method for an ink jet coating machine, wherein the ink jet head is transferred to the ink jet head.

  In the above invention, it is preferable to transfer the ejection data by serial transmission or parallel transmission.

  In the invention described above, the ink jet head is preferably a multi-drop ink jet head in which a minute droplet is continuously ejected a plurality of times based on a gradation value to change a single ejection amount.

  According to the present invention, by incorporating data in advance in the ejection data parameter, it becomes possible to control a desired ejection amount without increasing the number of bits, that is, without increasing the number of bits, that is, inkjet coating. The present invention has an excellent practicality effect such that multi-tone discharge can be performed without greatly changing the machine configuration of the machine.

Next, the present invention will be described in detail.
In one embodiment of the ink jet discharge data multi-gradation method of the ink jet coating machine according to the present invention, the gradation value is changed to 4 bits, that is, 16 gradation values from 1 to 15 including 0. An ejection data parameter file that stores data for this purpose is prepared. Then, when transferring the discharge data corresponding to the number of discharge gradations to the ink jet head side of the ink jet coating machine, the discharge data is calculated based on the data written in the discharge data parameter. In this way, the number of discharge gradations is increased in order to increase the number of gradations, and the discharge data that has been converted to multiple gradations is transferred to the inkjet head, thereby ejecting more than the normal gradation value in 4 bits. It is provided so that it can.

  The ink jet head of the ink jet coating machine used in the method of the present invention is the share wave mode ink jet head described with reference to FIG. 1, and is an ink jet head that repeatedly and sequentially discharges the A, B, and C rows.

  A simple operation flow until the ink jet head discharges is shown in FIG. In this flow, first, data to be ejected from the ink jet head is received by an arithmetic circuit on the ink jet head side, which is converted to multi-gradation data to be described later by the arithmetic circuit, and the data is transferred to the A-phase line buffer. Based on the transferred data, ejection is started from the A-phase nozzle. Further, simultaneously with the start of ejection from the A-phase nozzle, data for ejection is transferred from the A-phase line buffer to the B-phase line buffer. After completion of ejection from the A-phase nozzle, ejection is started based on the data transferred to the B-phase nozzle. Simultaneously with the start of ejection from the B-phase nozzle, data for ejection is transferred from the B-phase line buffer to the C-phase line buffer. After the completion of ejection from the B-phase nozzle, ejection is started based on the data transferred to the C-phase nozzle. Further, simultaneously with the start of ejection from the C-phase nozzle, data for ejection is transferred to the A-phase line buffer. After the completion of ejection from the C-phase nozzle, it is determined whether or not line ejection has been performed a set number of times by the line counter, and ejection is started based on the data transferred to the A-phase nozzle. Thereafter, the above-described operation is repeated for the number of lines to create an image.

  In the present embodiment, as described above, the operation of the arithmetic circuit is added while the necessary discharge data in the 16 gradation values is sent to the line buffer, and the changed data is sent to each nozzle. I am doing so.

An ejection data parameter file may be prepared for the arithmetic circuit, and addition may be set as an arithmetic method for increasing the number of ejection gradations. For example, when “n” is included in date 1 in the ejection data parameter for changing the gradation value, “n” is added to all 16 gradation values including 0 to 1 to 15. That is, 0 + n, 1 + n, 2 + n, 3 + n, 4 + n, 5 + n, 6 + n, 7 + n, 8 + n, 9 + n, 10 + n, 11 + n, 12 + n, 13 + n, 14 + n, 15 + n.
For example, when “8” is included in date 1, “8” is added to all 16 gradations including 0 to 1 to 15. That is, one pixel can be formed with a gradation value range of 0 to 15 and 8 to 23.

Further, multiplication may be set as a calculation method for increasing the number of discharge gradations. In the ejection data parameter for changing the gradation value, for example, the condition in which “m” is entered in date 2, all 16 gradation values from 1 to 15 including 0 are multiplied by “m”. That is, 0 × m, 1 × m, 2 × m, 3 × m, 4 × m, 5 × m, 6 × m, 7 × m, 8 × m, 9 × m, 10 × m, 11 × m, 12 × m, 13 × m, 14 × m, and 15 × m.
For example, when “3” is included in date2, all the 16 gradation values from 1 to 15 including 0 are multiplied by “3”. That is, one pixel can be formed in the range of 0 to 15 gradation values ranging from 0 to every 45.

Furthermore, addition and multiplication can be set as the calculation method for increasing the number of ejection gradations. For example, when “a” is entered in date 3 and “b” is entered in date 4 in the ejection data parameter for changing the gradation value, “b” is assigned to all 16 gradation values including 0 to 1 to 15. Multiply and then add "a". That is, (0 × b) + a, (1 × b) + a, (2 × b) + a, (3 × b) + a, (4 × b) + a, (5 × b) + a, (6 × b) + a , (7 × b) + a, (8 × b) + a, (9 × b) + a, (10 × b) + a, (11 × b) + a, (12 × b) + a, (13 × b) + a, (14 × b) + a, (15 × b) + a.
For example, when “15” is included in data3 and “2” is included in date4, “2” is multiplied by all 16 gradation values including 0 to 1 to 15, and then “15” is added. That is, one pixel can be formed in the range of gradation values from 0 to 15 every 15 to 45.

  Other additions. The desired discharge amount can be controlled by finely adjusting the multiplication.

A specific embodiment will be described. The ink jet head used in the examples operates as shown below.
Base clock: 25 MHz
Effective nozzle: 399
4-bit 16 gradation, multi-drop PZT share mode, drop-on-demand inkjet system

  In the arithmetic circuit of FIG. 3, data for multiplying all 16 gradation values including 0 to 1 to 15 by “2” is set. In the data implemented this time, ejection was performed at “30” obtained by multiplying 15 by 2.

  As a comparative example, conventional waveform data until ejection is shown in FIG. As for the waveform, an A, B, C phase ejection timing signal is generated after a print start trigger signal is generated. At this time, the ejection data is printed at the A, B, and C phase positions of the ejection timing signal. The data to be printed forms one pixel in a conventional 4-bit 16 gradation range.

Waveform data until ejection in the example is shown in FIG. Compared to FIG. 4, when the ejection timing signal is generated, the ejection data increases without changing the time until the next signal.
If this is increased to 5 bits so as to be the same as the same gradation value, since the base clock is 25 MHz, 1 bit takes 40 ns. From this, in order to transfer the number of bits of one group, there is a difference in the number of 133 bits between 4 bits and 5 bits as in the above formula. If you increase to 5 bits,
40 ns x 133 = 6320 ns
The transfer time per group increases.

  As a result, it is possible to perform ejection without reducing the stage conveyance speed. Further, the drop volume discharged 30 times per pixel can be discharged almost the same as the specified volume.

It is explanatory drawing which shows the nozzle structure of the inkjet head of a share wave mode. It is explanatory drawing which shows the operation | movement flowchart until it discharges from the conventional inkjet head. It is explanatory drawing which shows the operation | movement flowchart until it discharges from the inkjet head of this invention. It is explanatory drawing which shows the example of a waveform until it discharges from the conventional inkjet head as a comparative example. It is explanatory drawing which shows the example of a waveform until it discharges from the inkjet head of this invention.

Explanation of symbols

  1 ... Inkjet head

Claims (3)

  When transferring ejection data to the inkjet head of the inkjet coating machine, the gradation value including 0 corresponding to the number of ejection gradations, which is the ejection data, is changed to the value of the ejection data parameter having data for changing the gradation value. Inkjet coating characterized in that, based on the data, an arithmetic circuit on the ink jet head side calculates in the direction of increasing the number of ejection gradations to increase the number of gradations, and transfers the gradation-converted ejection data to the inkjet head Machine inkjet discharge data multi-gradation method.   The method of increasing the gradation of inkjet discharge data in an inkjet coating machine according to claim 1, wherein transfer of the discharge data is performed by serial transmission or parallel transmission.   The inkjet of the inkjet coating machine according to claim 1 or 2, wherein the inkjet head is a multi-drop inkjet head that changes a discharge amount of one time by continuously discharging a minute droplet a plurality of times based on a gradation value. Discharge data multi-gradation method.

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