JP5058523B2 - Recording method and recording apparatus - Google Patents

Description

  The present invention relates to a recording head driving method, a recording apparatus, and a recording method corresponding to an inclination of a nozzle row in a recording head including a nozzle row composed of a plurality of nozzles.

  In recent years, with the development of personal computers, printer technology has also dramatically improved, and high-quality (high image quality) image output can be performed. In order to enable high-quality recording (printing), it is necessary to adjust registration (hereinafter referred to as registration or registration adjustment).

  Conventionally, there are many methods for correcting the landing position deviation between the nozzles of each color, and for correcting the landing position deviation of the same color ink in the forward scanning and the backward scanning of the recording head when performing bidirectional printing. There is technology and it is well known and implemented in many products.

  As shown in FIG. 2, the current recording head (printing head) is mainly a color printing head having a two-nozzle row configuration of large dot nozzle rows and small dot nozzle rows for each color, in order to improve printing speed. The number of nozzles is increasing. Here, an example is shown in which each of the large dot nozzle row and the small dot nozzle row is composed of 192 nozzles.

  In these print heads, the drive of the print head is different for each nozzle group by dividing a plurality of nozzles arranged in a row in the column direction (sub-scanning direction) into nozzles at a certain interval and in the same group. A method of driving at timing is generally used, and the method is disclosed (Patent Document 1). By driving the nozzles in a time-sharing manner in this way, it is possible to improve the ink supply speed and stability and reduce the power consumption required for ejection.

  FIG. 3 is a table showing the configuration of the nozzles in each block as an example of a nozzle row divided into 16 blocks. As shown in the table, the nozzles are arranged at intervals of 16 nozzles in the same block. In other words, by adopting the same block for nozzles that are spaced at a certain interval, the structure is less susceptible to the effects of driving adjacent nozzles.

  There has been disclosed a method for performing registration adjustment for landing position deviation between nozzles of each color and landing position deviation of the same color ink in forward scanning and backward scanning when bidirectional printing is performed (Patent Document 2).

Further, in order to correct the landing position deviation of the ink droplets when there are a plurality of printing speeds, the time-division driving interval (t) is controlled according to the printing speed. That is, it is disclosed that the landing position deviation is eliminated by shortening t during high-speed printing and lengthening t during low-speed printing (Patent Document 3).
JP 2000-71433 A JP 2001-129985 A JP-A-5-84899

  Some printer apparatuses have a configuration in which the capacity of a memory (RAM) mounted on the apparatus is reduced to the maximum for cost reduction. In this case, since the memory capacity is limited, a method of performing dot interpolation by reducing the resolution of print data in the scanning direction and repeating scanning in the main scanning direction (multipass printing) is common. According to this method, if the printer device actually holds in the memory and the print resolution that can be printed is 600 dpi, 600 dpi printing is performed 8 times in order to realize the print resolution in the main scanning direction of 4800 dpi. This is realized by multipath.

  As described above, when the actual resolution in the main scanning direction is relatively low, for example, when printing data of 600 dpi is recorded as the recording image data with the recording resolution, the image data for one column is within a range of 600 dpi by time-division driving. Will be scattered. For this reason, in the conventional printing method, since the dot recording position can be shifted only in 600 dpi units, the registration adjustment between nozzles can naturally be performed only in 600 dpi units.

  In addition, the number of nozzles of the recording head is increasing, and it is necessary to cope with this.

  In addition, there are variations in the print head manufacturing, and there is an inclination in the nozzle row that occurs when the print head is fitted and set in the carriage unit on the printer apparatus. For this reason, it is necessary to adjust the deviation in the ejection direction between the 0 nozzle and the 191 nozzle.

  By the way, as a registration adjustment method, there are a method of shifting print data by a plurality of pixels in units of recording resolution (printing resolution), a method of shifting half a pixel, and a method of shifting a specified time from a reference timing for printing.

  For example, a method of shifting a plurality of pixels in units of columns is performed to correct the landing position deviation between the nozzles of each color and to roughly adjust the landing position deviation of the same color ink in the forward scan and the backward scan when performing bidirectional printing. . In this case, when printing is performed at 600 pdi, shifting in units of 600 dpi is possible. The half pixel shift can be performed at an interval of 1/2 pixel of the print resolution. In the above example, a shift of 1200 dpi is possible. The method of shifting the specified time from the reference timing for printing is a shift within one column time, and the printing timing can be shifted in units of the basic clock that operates the printer system. This shift is used to correct minute positional deviations due to individual differences during head manufacture, differences in recording environment, and the like.

However, in any of the above methods, it is possible to shift the printing start position, but the time for ejecting the blocks constituting one column by time-division driving does not change. For example, when printing is performed at a printing speed (carriage speed) of 40 inches / sec and a resolution of 600 dpi, the time required for all the nozzle rows in one column to discharge is as follows:
Tcolumn = (1/40 (inch / sec)) / 600 (dpi) = 41 μs
It is. The most popular method for generating the discharge interval for each column is that the encoder on the carriage reads a scaler installed in the moving direction of the carriage. Therefore, in the printing area where the carriage speed is a constant speed section, the discharge interval for each column is generated uniformly.

The drive time of a block that divides one column is a time obtained by dividing one column time by the number of blocks. For example, in the above condition, the time interval of one block divided into 16 blocks is
Tblock = Tcolumn / 16 (Blocks) = 2.60 μsec
It becomes.

  As described above, since the time interval and the block time interval of one column are generated evenly based on the reference timing, even if the registration adjustment is performed, only the discharge start time is deviated and the discharge time of one column is not changed. With the existing configuration, the ejection time for one column in the raster direction is determined by the printing speed of the carriage and the printing resolution. However, in reality, the printing speed of the carriage is limited to several modes from the optimum value of the ejection frequency of the print head, so it is considered that the ejection time of one column depends on the printing resolution.

  Recently, the amount of ink droplets has been minimized in order to realize high-quality printing such as silver salt photography, and dots of only 1 to 2 pl can be ejected. In the case of such a minimal dot, the size of the dot formed on the paper surface is minimal. Therefore, a time difference is generated for each block by time-division driving, and a phenomenon may occur in which the discharge positions of all the nozzles do not coincide with each other. In the conventional print head, the amount of ink droplets ejected from the nozzles was also as large as 20 pl to 50 pl. Therefore, the dots overlapped on the paper surface, and it was rare to distinguish the positional deviation of the dots by time-division driving in the same column.

  When calculated from the above example, a block drive time difference of about 39 μsec occurs between the first block and the last 16 blocks. Although the human eye cannot detect the displacement of the ink droplet of 2 pl, if such a shift occurs in the formed image on the paper surface, it may be detected as a striped pattern.

  For the above reasons, especially when the printing resolution is low, it is better to drive all the blocks within a certain period of time rather than time-division driving the blocks constituting one column in equal time. In addition, the positional deviation of dots due to time-division driving hardly occurs.

In order to solve the above problems, a print buffer for holding a recording head having a nozzle row of one row constituted by the second group of a plurality of successive first group and a plurality of consecutive nozzles consisting of nozzle, the recording data The recording method of the recording apparatus that performs recording by scanning the recording head includes recording data for one column from the print buffer for each period of resolution of the recording data held in the print buffer. A step of reading and storing in the holding buffer, and a control step of controlling the drive of the print head using drive data based on the print data for one column, the control step comprising: On the basis of the information relating to the inclination of the first and second groups, the first driving period having a width of ½ period of the resolution period, The driving data is selected in one of a period of a second driving period having a width of ½ period of the resolution period after one driving period, and the recording data for the one column stored in the holding buffer is selected. The driving data corresponding to the first and second groups is generated from the recording data for one column and divided into two, and the first driving period or the second driving period is selected in the first driving period. In addition, the driving of the recording head is controlled based on the driving data so as to drive the second group.

  As described above, the inclination of the nozzles in one nozzle array of the print head can be discharged and corrected with a resolution higher than that of the recorded image data. Further, when combined with means for shifting print data in units of N nozzle groups, correction can be made in stages in units of N nozzle groups, and the inclination of the nozzles in one nozzle row can be corrected in a finer range. It becomes possible.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 4 is a perspective view of the printer (recording apparatus). Reference numeral 1 in the figure denotes a printer apparatus. The functional parts of the printer apparatus are roughly classified into a carriage 2, a timing belt 3, a conveyance roller 4, a paper discharge roller 5, a cleaning unit 6, a carriage motor 7, and a platen 8. The carriage is connected to a pulley attached to the shaft of the carriage motor 7 and a part of the timing belt 3 stretched around the pulley in a symmetrical position to transmit the driving force of the carriage motor 7. The paper discharge roller 5 is set to rotate slightly earlier than the transport roller 4 in order to apply an appropriate tension to the paper on the platen 8.

  FIG. 5 shows the back surface of the carriage 2. The carriage is supported by the shaft 9 and can move left and right. An encoder 11 that reads the scaler 10 is installed on the back surface of the carriage 2. The encoder 11 reads the scaler 10 provided to extend to the printer device as the carriage unit 2 moves. The printer apparatus 1 sequentially observes the displacement amount of the carriage 2 and performs feedback control of the carriage motor 7 based on the information. Timing information for driving the print head is also generated based on the position information of the encoder 11.

  FIG. 6 is a diagram showing an overall configuration of an electric circuit of the printer. The main components of the recording apparatus are composed of a CPU 12, RAM 13, ROM 14, and ASIC 15. In this figure, each element is illustrated as a single component, but the case where all the elements are integrated in an LSI package is also included. The ROM 14 stores an OS, program firmware in a program area, a motor drive table, and the like.

  In addition to motor drive control, the ASIC 15 performs image processing, communication with the host computer via the interface 16, ink ejection control of the print head 17, and the like. Further, the RAM 13 has a reception buffer for temporarily storing data received from the host computer (host device), a temporary memory (temporary buffer) for image processing by the ASIC, a print buffer for storing recording data, and a motor drive. A work buffer that holds the data table is provided.

  The motor driver is mainly composed of two drivers 18 for carriage drive and 19 for paper conveyance, and 7 and 20 are a carriage motor and a paper conveyance motor, respectively. The combination of the motor driver and the motor in the figure is an example, and the number of motors and the number of motor drivers may be any number depending on the printer device.

  Reference numeral 21 denotes a power source, which is a part that generates a logic power source for driving a semiconductor device, a motor driving power source, and a head driving power source from a commercial power source.

  The print head is driven by dividing a plurality of nozzles (recording elements) provided in a line in the column direction of FIG. 2 into several nozzle groups, and each nozzle group is driven at a different timing.

  As described with reference to FIG. 3, the nozzles are arranged in such a manner that 12 nozzles every 16 nozzles are configured in the same block. In this way, by adopting the same block for nozzles that are spaced at a certain interval, the configuration is less likely to be affected by the driving of adjacent nozzles.

  Next, the print head control block that drives the print head will be described. The print head control block is one block constituting the ASIC. FIG. 7 shows a block diagram of the print head control block.

  As shown in the figure, the print head control block is roughly divided into three component blocks, which are composed of a nozzle data generation block (NZL_DG) 22, a nozzle data holding block (NZL_BUFF) 23, and a print head control block (HEAD_TOP) 24. Is done. The reference timing signal for activating the nozzle data generation block 22 and the print head control block 24 is composed of a window 25, a column TRG 26, and a latch TRG 27 from a discharge timing generation block (not shown) based on position information acquired from the encoder. A print timing signal is supplied.

  Specifically, the window 25 is flagged when the carriage moves in the main scanning direction and reaches the designated print position (Window Open), and the flag is lowered at the print end position (Window Close). The number of control signals of the window 28 corresponds to the number of nozzle rows of the print head. For example, suppose that black has an Odd / Even two-nozzle row configuration, and a color has a six-nozzle row configuration of Cyan Large, Cyan Small, Magenta Large, Magenta Samell, Yellow Large, and Yellow Small. In the case of a color print head in which the large and small nozzle arrays cannot be driven simultaneously, the color large and small nozzle arrays are generally handled in the same window. That is, black is composed of two windows and three windows of color, for a total of five windows. Column TRG 26 is a trigger signal output at the column interval, and the interval between the column triggers is the print resolution in the raster direction, that is, the main scanning direction. The Latch TRG 27 is generated at a timing at which the column interval is equally divided by the number of blocks, and serves as a time division drive switching timing. When configured with 16 blocks as described in the present embodiment, 16 Latch TRGs are generated within one column time.

  The nozzle data generation block (NZL_DG) 23 includes a DMA (Direct Memory Access) transfer block 28, a print data mask / latch block 29, and a data rearrangement block 30.

  The DMA transfer block 28 takes in the print data stored in the print buffer provided in the RAM 13 by DMA transfer. The number of data to be captured when all the nozzles in one color nozzle row shown in FIG. 2 are used is 16 (bits) × 12 (DMA count) = 192 (bits). The number of DMAs is determined by the number of nozzles used.

  Supplementally, the nozzle data generation block 22 counts the number of times the column TRG 26 is input. Each time the column TRG 26 inputs twice, the DMA transfer block 28 operates to read one column of data from the print buffer.

  The print data mask / latch block 29 has a function of latching data acquired by DMA transfer in correspondence with the nozzle position and masking unused nozzles based on register information (not shown). The nozzle mask can be set in units of one nozzle. The data rearrangement block 30 rearranges data based on the print nozzle block. In other words, the print data is rearranged in the nozzle data string of each block based on the nozzle information constituting the block shown in the table of FIG.

  A main signal for starting the nozzle data generation block (NZL_DG) 22 is performed by a combination of the window 25 and the column TRG 26. That is, when the data reaches the print designation position in the window 25 and the flag is set, and acquisition of the Column TRG 26, acquisition of print data is started. When the window 25 is closed, the print data acquisition is stopped.

  The nozzle data holding block (NZL_BUFF) 23 is a buffer for holding nozzle data having the configuration of each block shown in the table of FIG. The reason why the arrangement of the nozzles constituting each block of the print head and the arrangement of the data coincide with each other is to facilitate the management of the data and thereby facilitate the generation of the print drive data in the print head. . The buffer has a two-stage configuration of a first buffer 31 and a second buffer 32. Each buffer is configured to hold one column of data for all nozzle rows. The black 1 nozzle array has a data amount of 10 (bits) × 16 (blocks) = 160 (bits), and the color has a data quantity of 12 (bits) × 16 (blocks) = 192 (bits). This buffer has a two-stage configuration to prepare the next one column data while transferring each block data in one column to the print head. The first buffer 31 is the writing side, and the second buffer 32 is the reading side. It is. The selector block 336 selects a sequential block based on a selection signal from the block selector block 34 of the print head control block (HEAD_TOP) 24 and outputs nozzle data for each block. The bus width of nozzle data is 16 bits. In the case of color nozzle data, nozzle data is assigned to all 16 bits, but in the case of black nozzle data, only 10 bits are set, so data “0” is set in the upper 2 bits. The reason why the bus widths of the nozzle data are set in this way is to use the circuit of the print head control block (HEAD_TOP) 24 in each color common circuit.

  The print head control block (HEAD_TOP) 24 includes a block selector block 34, a shift register block 35, a data transfer timing generation block 36, a temperature estimation dot counter block 37, a k value dot counter block 38, a pulse generation block 39, and printing. The head drive signals H_LACTH40, H_CLK41, H_D42, and H_ENB43 are included. The activation of this block is performed by the Windows 25, Column TRG 26, and Latch TRG 27 signals.

  The block selector block 34 outputs a block selection signal to the selector block 33 of the nozzle data holding block (NZL_BUFF) 23 according to the block order by the time division drive by the trigger signal Latch TRG27. Simultaneously with the output of this block selection signal, the block selection signal is also output to the shift register block 35.

  The shift register block 35 converts the nozzle data and block selection signal output from the nozzle data holding block (NZL_BUFF) 23 into serial data by the shift register, and outputs the serial data to the print head drive data H_D42.

  Supplementally, the shift register block 35 has a null data setting function. This function is to generate H_D 42 including null data based on block information and drive sequence selection information. For example, null data is assigned from the nozzle 177 of the group D11 to the nozzle 192 instead of the print data. If this null data is assigned, it is possible to stop ink ejection in units of groups even if the drive sequence works. This function can be set independently regardless of the first half drive or second half drive by selecting the drive sequence.

  Since H_D42 is a two-nozzle row of black nozzle rows EVEN and ODD, it consists of two drive signals. Regarding color, since the large nozzle row and the small nozzle row are common data signals, they are composed of three drive signals and are composed of a total of five.

  The data transfer timing generation block 36 uses the Latch TRG 27 as a reference signal to cause the print head to latch the transfer clock for transferring the print head drive data H_D 42 to H_CLK 41 and the data in the shift register in the print head. Latch signal H_LATCH40 is generated. In addition, the data shift timing is output to the shift register block 35.

  The temperature estimation dot counter block 37 and the k value dot counter block 38 are calculation blocks for correcting the drive pulse width of the heat enable signal H_ENB 43 generated by the pulse generation block 39 according to the ejection frequency of the nozzles. It is. The temperature estimation dot counter block 37 is used to change the correction table at intervals of several tens of ms. The k-value dot counter block 38 uses the Latch TRG 27 as a reference signal, and corrects the optimum heat pulse width in the next block from the temperature rise state due to the nozzle discharge frequency in the previous block in units of blocks (hereinafter, k Value control).

  The heat enable signal H_ENB 43 is composed of one black and two colors. The reason why the two colors are used here is to disperse the energy required for ejection by shifting the timing of heat.

  Prior to the description with reference to FIG. 11, the conventional drive timing will be described. FIG. 8 shows the drive timing of the print head per column. The output interval of the Column TRG 26 is 600 dpi. Column TRG26 is an internal signal, and H_LACTH40, H_CLK41, H_D42, and H_ENB43 are print head drive signals. As shown in the figure, one column is composed of 16 blocks and is driven by time division. The drive data H_D42 is transferred to the shift register in the print head by H_CLK41, and is latched by the falling edge of H_LACTH40.

  The data latched by H_LATCH 40 is ejected based on H_ENB 43 generated following H_LATCH 40. Further, while the H_ENB 43 is being generated, the next block of data is transferred. The data of this next block is latched by the H_LATCH 40 generated following the H_ENB 43. Thereafter, similarly, data transfer, data latch, and head drive are repeated for 16 blocks.

  The above is the description of the conventional drive timing. On the other hand, in the embodiment of the present invention, as shown in FIG. 11, the output interval of the column TRG 26 is 1200 dpi. Data transfer, data latch, and head drive timing are the same as in FIG.

  FIG. 9 shows the relationship between the transfer clock H_CLK41 and the print head drive data H_D42. The print head drive data H_D42 is configured to transfer data at both edges of H_CLK41 in order to shorten the transfer time. The frequency of H_CLK 41 is about 6 MHz to 12 MHz. In the data structure of H_D42, bits 0 to 11 are nozzle data. In the case of black, bits 2 to 11 are 10 bits, and in the case of color, bits 0 to 11 are 12 bits. 4 bits of bits 12 to 15 are block selection data BLE, and a drive block is selected in the print head from the 4 bits of BLE data, thereby realizing time-division driving.

  Bit 16 is a heater switching SEL for selecting a large nozzle row or a small nozzle row for the color head as described above. The large nozzle row ejects about 5 pl of ink from the nozzle, and the small nozzle row ejects about 2 pl of ink from the nozzle. Bit 17 is a dummy nozzle selection bit (DHE). When this DHE bit is enabled, ejection can be performed from several dummy nozzles at the beginning and rear of the nozzle row. The discharge of the dummy nozzle is provided to discharge the ink staying in the corner of the ink chamber when the print head is preliminarily discharged.

  FIG. 11 shows the discharge timing. The nozzle data generation block (NZL_DG) 22 generates nozzle data, and the nozzle data is latched in the first buffer 31 of the nozzle data holding block (NZL_BUFF) 23 and the nozzle data of the second buffer 32 is printed in the print head control block (HEAD_TOP) 24. The timing for discharging is shown in FIG.

  The resolution of the print data stored in the print buffer is 600 dpi. In the print head drive method, the nozzle data generation block (NZL_DG) 22 reads the image data stored in the print buffer at every other timing of the Column TRG 26 (column timing). The column interval is 1200 dpi, but the timing interval at which the nozzle data generation block (NZL_DG) 22 updates the nozzle data by this method is also 600 dpi, which matches the resolution of the image in the print buffer.

  On the other hand, the print head control block (HEAD_TOP) 24 has a selection function for driving the print head in either the first half column or the second half column with respect to two successive Column TRGs 26. Thus, the print data A in the figure is printed at the timing A1 or A2. The discharge at the timing of A1 or A2 is as shown in FIG. The same applies to data B to D. By this method, printing can be performed with a higher resolution than the recorded image data.

  The selection function described above has the following two types. In the first method, as shown in FIG. 11, print head drive data is set corresponding to one of the first half drive and the second half drive for two consecutive column timings. For example, when the first half drive is selected for D11, the null data setting function of the shift register block 35 is used for the second half drive. Thus, for D11, recording is performed by ink ejection corresponding to the recording data at the first half driving timing, and ink ejection is prohibited and recording is not performed at the second half driving timing because of null data. Thus, for each group, it is possible to set ink ejection or prohibit ink ejection at a desired drive timing.

  In the second method, as shown in FIG. 15, one of the first half driving of FIG. 15A and the second half driving of FIG. 15B is set for two consecutive column timings. It may be set whether the ink ejection corresponding to the recording data is performed by the first half driving or the second half driving. In this case, the shift register block 35 does not need to set null data.

<Embodiment 1>
FIG. 12A is a diagram showing a nozzle arrangement of a color head in which the color nozzle row is composed of 192 nozzles. When the nozzle row formed as shown in the figure is fitted and fixed to the carriage unit, there may be a deviation in the X-axis direction as shown in FIG. This X-axis direction is the scanning direction (moving direction) of the recording head in the recording apparatus. The Y-axis direction is the conveyance direction of the recording medium (recording paper) in the recording apparatus.

  In the case of a multi-nozzle row as another factor of these deviations, there is a possibility that the displacement of the nozzles in one nozzle row may occur due to manufacturing variations. Due to these factors, for example, as shown in 12 (b), the nozzles 1 to 96 and 97 nozzles to 192 nozzles are not linear but the nozzle positions are different by a minute distance α, regardless of the same nozzle row. May end up. In this figure, in order to simplify the explanation, it is assumed that a case in which it is shifted in the X-axis direction but is inclined obliquely is approximated.

Hereinafter, a description will be given with reference to FIG. For the nozzle row corresponding to each color, 16 nozzles are grouped into one group. As shown in the figure, if the color nozzle is composed of 192 nozzles, it is composed of 12 groups. These groups are assigned to register bits as follows: D0: 177 to 192 nozzles D1: 161 to 176 nozzles D2: 145 to 160 nozzles D3: 129 to 144 nozzles D2: 113 to 128 nozzles D4: 97 ~ 112 nozzles D5: 81 ~ 96 nozzles D6: 65 ~ 80 nozzles D7: 49 ~ 64 nozzles D9: 33 ~ 48 nozzles D10: 17 ~ 32 nozzles D11: 1 ~ 16 nozzles Although not shown in the figure, There is also an enable register that enables and disables the function. The first nozzle of the print head corresponds to the downstream side in the paper discharge direction.

  When the register for enabling the register function is enabled and “0” is set for each bit, the group ejects 600 dpi print data in the first half of 1200 dpi. When “1” is set, ejection is performed at 1200 dpi in the latter half.

For example, as shown in FIG. 12B, if there is a shift in one color nozzle row,
1 to 96 nozzles (D11 to D6) are set to “0” and set to drive at the first half 1200 dpi, and 97 to 192 nozzles (D5 to D0) are set to “1” and driven at the second half 1200 dpi. Set to do. This setting is performed based on information related to the inclination of the nozzle row of the recording head.

  Thus, by providing a time difference in the drive timing (ejection timing), it is possible to correct the positional deviation of the nozzles occurring in one nozzle row.

  In other words, a plurality of drive start timings are provided in a period corresponding to 600 dpi (drive timing interval is 1200 dpi). The position shift can be corrected by selecting an appropriate driving start timing among them. That is, a predetermined period is divided into a plurality of periods (for example, divided into two), and one of the divided periods is selected.

  In other words, the first driving step and the second driving step having a cycle (1200 dpi) shorter than a predetermined cycle (600 dpi) are provided, and the nozzles corresponding to each group are driven in the first driving step (first half). Driving) or the second driving process (second half driving).

  In this example, since the 97 to 192 nozzles are shifted to the downstream side in the scanning direction with respect to the reference position of the lesle row, the ejection timing may be delayed. In this method, since the ejection timing is controlled at a resolution of 1200 dpi, which is higher than the resolution of the print data of 600 dpi, correction can be performed only with the ejection timing regardless of the print data.

<Embodiment 2>
Next, in the second embodiment, in addition to the control of the first embodiment described above, a plurality of nozzles are grouped into one group, and control for shifting (shifting) the reading timing of recording data (printing data) in units of one group is performed. Correction of the local nozzle position in one nozzle row is performed. The control described below is performed based on information related to the inclination of the nozzle array of the recording head.

  In FIG. 10, the recording data is stored in the recording buffer with the position corresponding to the inclination of the nozzle row. FIG. 10 is an explanatory diagram when one nozzle row is composed of three groups (one group is composed of 16 nozzles). Here, the horizontal address in FIG. 10 corresponds to the scanning direction of the recording head. One address corresponds to one group, and the recording data stored in one address is data for one column.

  For example, in the case of the nozzle row of the first color, there is a shift of one column between the first group and the second group (the inclination correction value is 1), and there is a difference between the second group and the third group. It is assumed that there is a shift of one column between them. For this reason, when the first group is used as a reference, there is a shift of two columns for the third group (the value of inclination correction is 2).

  For this reason, the data corresponding to each group is shifted by one column and stored in the recording buffer. In this figure, the data read timing of the second group is described as being delayed by one column from the data read timing of the first group.

  The recording data corresponding to the first group is stored in the order of 24, 2A, 30,. The recording data corresponding to the second group is stored in order of 2C, 32, 38,. The recording data corresponding to the third group is stored in the order of 34, 3A, 40,.

  The recording data may be similarly stored for the second color. In the case of the nozzle row of the second color, there is no deviation between the first group and the second group (inclination correction value is 0), and one column exists between the first group, the second group, and the third group. It is assumed that there is a minute shift. For this reason, the position of the start address of the data corresponding to the first group and the start address of the data corresponding to the second group are the same in the scanning direction.

  Note that even when the read timing is advanced, this can be dealt with by shifting the storage position of the recording data. For example, when the data read timing of the second group is advanced by one column from the data read timing of the first group, the address 20 in FIG.

  FIG. 13 shows an example in which three-stage positional deviation occurs in one nozzle row. Also in FIG. 13, the arrow indicates the scanning direction of the recording head.

  First, in the area A, it is assumed that there is a shift of about 1200 dpi in resolution in the scanning direction with respect to the reference nozzle position. In this case, the displacement of the nozzle can be corrected by discharging the printing data of 600 dpi as it is and performing the second-half driving of 1200 dpi. Since the nozzles (1, 2, 3, 190, 191, 192) scattered at the reference position of the nozzle row do not need to be corrected, ejection is performed by the first half drive of 1200 dpi.

  Next, in the region B, it is assumed that there is a shift of about 600 dpi in resolution with respect to the reference nozzle position. In this case, since the printing data is 600 dpi, the reading of the printing data may be shifted so as to advance the reading of one pixel (600 dpi). However, the first half drive of 1200 dpi is performed. This is because the first half and the latter half of 1200 dpi are performed for correction within one nozzle row, and therefore it is necessary to match the drive timing for ejection with one nozzle row.

  Next, in the region C, it is assumed that there is a shift of about 600 dpi + 1200 dpi in resolution with respect to the reference nozzle position. In this case, it is possible to correct the nozzle position by combining the shift of the print data and the second half drive of 1200 dpi. As described in the first embodiment, these corrections are performed with 16 nozzles as one group.

  As described above, according to the second embodiment, the nozzles in one nozzle row can be combined with the group of 16 nozzles in the print data shift and the time interval of 1200 dpi by combining the discharge of the first half column or the second half column. It is possible to more precisely correct the position variation in groups.

<Embodiment 3>
In the first and second embodiments described above, the drive control unit is set to 16 nozzle units. However, as described in the third embodiment, the drive control unit may be set to 8 nozzle units.

  By using such a configuration, adjustment is made according to the inclination of the nozzle row when the method of writing (storing) the recording data to the recording buffer differs from the method of reading the recording data stored in the recording buffer. It can be performed.

  Specifically, when recording data is stored in the recording buffer, it is stored in one address in units of 16 bits. On the other hand, when recording data is read from the recording buffer, 16-bit data is read across two addresses.

  When the carry amount is not an integral multiple of the number of nozzles provided in one block, such access to the recording buffer is executed. In other words, this is a case where the paper is transported by an amount different from the transport amount corresponding to an integral multiple of 16 nozzles. Such sheet conveyance is performed when recording the front end, the rear end, and the like of the recording sheet.

  For example, if the scanning area of the recording head is other than the end (front end, rear end) of the recording paper, the conveyance corresponding to 48 nozzles is performed. Scan recording after this conveyance is performed using 48 nozzles.

  On the other hand, conveyance corresponding to 40 nozzles is performed at the end portions (front end and rear end) of the recording paper. After the conveyance corresponding to the 40 nozzles is performed, null data is assigned to some nozzles (1 to 8 nozzles), and 9 to 48 nozzles are used for recording. For example, 1 nozzle data is assigned to 9 nozzles, and 2 nozzle data is assigned to 10 nozzles. In this way, the allocation of the recording data to the nozzles is offset by 8 nozzles.

  As described above, the control for changing the drive control unit is performed based on the amount of the recording paper transported. This control is performed, for example, by the CPU 12 or the ASIC 15 shown in FIG.

  In the case where there is an offset to the nozzle in this way, the positional deviation cannot be corrected in the above-described embodiment. However, as described above, the positional deviation can be corrected by making the drive control unit correspond to the offset amount.

  The control correction unit described above is not limited to 8 nozzle units, but may be a value corresponding to the number of null data to be allocated to the nozzles, such as 4 nozzle units. If another expression is used, a number corresponding to an amount different from the conveyance amount corresponding to 16 nozzles may be used.

  As described above with reference to the three embodiments, it is possible to correct the inclination of the arrangement of the nozzles in one nozzle row at a resolution higher than the resolution of the image data. Further, when combined with means for shifting print data in units of N nozzle groups, correction can be made in stages in units of N nozzle groups, and the inclination of the nozzles in one nozzle row can be corrected in a finer range. It becomes possible.

<Other embodiments>
In the control embodiment described above, the number of drive control units, the number of blocks constituting the print buffer, and the like are not limited to the above-described numbers. Further, the capacity of the print buffer may be smaller than the capacity used for one scan recording. For example, the number of blocks may be set to a number less than 8 (for example, 2 or 3), and data used for recording may be rewritten and control to reuse the blocks may be performed. Although the shift register block 35 has been described as having a null data setting function, the shift register block 35 may be provided in a circuit block different from the shift register block 35 as long as it is inside the print head control block 24.

Explanatory drawing in the embodiment Diagram showing the arrangement of color nozzle rows Table showing the relationship between the nozzles constituting each block Perspective view of recording apparatus Viewed from the back side of the carriage Diagram showing the control configuration of the recording device Diagram showing the configuration of the print head control block Diagram showing drive timing of recording head per column Diagram showing the timing of data transfer to the recording head Explanatory drawing about storage of recorded data Timing chart of the first half drive and second half drive of the recording head Explanatory drawing of the position shift of the nozzle in Embodiment 1. Explanatory drawing of the position shift of the nozzle in Embodiment 2. The figure explaining the structure of the data stored in the recording buffer Explanatory diagram of the timing of the first half drive or second half drive

Explanation of symbols

22 Nozzle data generation block (NZL_DG)
23 Nozzle data holding block (NZL_BUFF)
24 Printhead control block (HEAD_TOP)
25 Windows
26 COLUMN TRG
27 LATCH TRG
28 DMA transfer block 29 Print data mask / latch block 30 Data rearrangement block 31 Fast buffer 32 Second buffer 33 Selector block 34 Block selector block 35 Shift register block 36 Data transfer timing generation block 39 Pulse generation block 40 H_LATCH
41 H_CLK
42 H_D
43 H_ENB

Claims (6)

It includes a plurality of consecutive recording head comprising a nozzle array of one row constituted by the second group of the first group and a plurality of consecutive nozzles consisting of nozzle, a print buffer for holding the recording data, wherein the recording A recording method of a recording apparatus that performs recording by scanning a head,
A step of reading out recording data for one column from the print buffer and storing it in the holding buffer for each period of resolution of the recording data held in the print buffer, and drive data based on the recording data for the one column And controlling the drive of the recording head using
In the control step, the first and second groups are divided into a first driving period having a width of ½ period of the resolution period and the first driving period based on information on the inclination of the nozzle row. Select the driving period in the second driving period with a width of 1/2 period of the resolution period later, and divide the recording data for one column stored in the holding buffer into two And generating drive data corresponding to the first and second groups from the recording data for one column,
A recording method, wherein driving of the recording head is controlled based on the driving data so as to drive the first and second groups in the selected first driving period or the second driving period. . In the control step,
The recording data of the group selected to be driven in the first driving period is assigned null data in the second driving period,
The recording data of the group selected to be driven in the second driving period is generated by allocating null data in the first driving period, thereby generating the driving data. Recording method.   The recording method according to claim 1, wherein the recording data for one column of the holding buffer is read twice within the period of the resolution. The recording method further includes a step of reading the recording data from the holding buffer in a plurality of times at a first period which is a predetermined period between the storing step and the control step,
The recording method according to any one of claims 1 to 3, wherein the control step generates drive data based on the recording data read out in a plurality of times.   The recording method according to claim 4, wherein the length of the first period is an integer of a half period of the resolution period. A recording head having a nozzle row of one row constituted by the second group of a plurality of successive first group and a plurality of consecutive nozzles consisting of nozzle,
A print buffer that holds recorded data;
Storage means for reading out recording data for one column from the print buffer and storing it in the holding buffer for each period of resolution of the recording data held in the print buffer, and driving based on the recording data for one column Control means for controlling the drive of the recording head using data,
The control means determines the first and second groups based on information relating to the inclination of the nozzle row, a first driving period having a width of ½ period of the resolution period, and the first driving period. Select the driving period in the second driving period with a width of 1/2 period of the resolution period later, and divide the recording data for one column stored in the holding buffer into two And generating drive data corresponding to the first and second groups from the recording data for one column,
A recording apparatus that controls driving of the recording head based on the driving data so as to drive the first and second groups in the selected first driving period or the second driving period. .

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