JP4461756B2 - Printing apparatus, printing method, and printing program - Google Patents

Description

  The present invention relates to a printing apparatus, a printing method, and a printing program.

  When printing is performed by a print head configured by arranging a plurality of nozzle rows in the sub-scanning direction (moving direction of the print medium) in the main scanning direction (scanning direction of the print head), It is necessary to accurately adjust the nozzle row so that it is parallel to the sub-scanning direction.

  That is, when the nozzle row has a deviation from the sub-scanning direction (when the print head has an inclination), as shown in FIG. 17, ejection is performed from nozzles at the same position in different nozzle rows. Since the landing positions of the ink droplets on the printing paper are different, hue deviation and banding (striped printing unevenness occurring in the main scanning direction) are also caused.

  In the example of FIG. 17, the print head 12 is provided with eight nozzle rows A to H, and each nozzle row includes a plurality of (for example, 180) nozzles. In this figure, the nozzle row is represented as a line segment. As shown in this figure, when the print head 12 has a shift of an angle α from the main scanning direction, for example, the landing position of the ink droplets ejected from the uppermost nozzle of the nozzle row A, and the nozzle Since the ink droplets ejected from the uppermost nozzles of the row H are displaced by a distance d, the hue may be shifted or banding may occur due to color mixing failure.

  Also, as shown in FIG. 18, when the print head 12 is inclined by an angle α, dots formed on the printing paper are obliquely arranged with respect to the main scanning direction, so that a hue shift or the like is caused. May occur.

  Therefore, in order to eliminate the inclination of the print head, a method for detecting the inclination of the print head by, for example, printing a vertical ruled line has been conventionally proposed (see Patent Document 1).

Japanese Patent Laid-Open No. 05-084777 (claims, summary)

  By the way, in order to correct the inclination of the print head based on the detection result by the method shown in Patent Document 1, a certain amount of trial and error is required, and the work takes time and the work efficiency decreases. There is a point. In addition, there is a problem that the manufacturing cost of the product increases as the work efficiency decreases.

  Therefore, a method for correcting and printing image data in accordance with the inclination of the print head has been proposed. However, when such correction processing is performed, time is required for the processing, so image printing is started. Then, there is a problem that it takes time to complete the printing.

  The present invention has been made based on the above circumstances, and the object of the present invention is to perform an optimal correction process according to the printing format even when the print head has an inclination. A printing apparatus, a printing method, and a printing program are provided.

  In order to solve the problem, the present invention has a print head in which a plurality of nozzle rows formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and corresponds to image data to be printed. In a printing apparatus that prints a desired image on a print medium by ejecting the ink that has been ejected from the nozzle, image data corresponding to the print format set by the print format setting means for setting the print format and the print format setting means And a supply unit that supplies the image data corrected by the correction unit to the corresponding nozzle rows.

  For this reason, even when the print head has an inclination, it is possible to perform optimum correction processing according to the print format.

  In another invention, in addition to the above-described invention, the print format setting means sets the print medium type, print resolution, ink type, or number of inks as the print format. For this reason, it is possible to execute an optimal correction process according to the type of print medium and the like, so that, for example, the printing speed can be improved.

  According to another invention, in addition to the above-described invention, the correction means performs a correction process on the image data so that the print position on the print medium does not shift according to the inclination of the print head. I am doing so. For this reason, it is possible to perform an optimal correction process according to the inclination of the print head.

  According to another invention, in addition to the above-described invention, the correction means corrects the image data in each of the main scanning direction and the sub-scanning direction of the print head. For this reason, it is possible to reliably prevent a reduction in image quality caused by the inclination of the print head.

  In addition to the above-described invention, in another invention, the correction unit appropriately combines either or both of correction in the main scanning direction and the sub-scanning direction according to the print format set by the print format setting unit. Correction for image data is executed. For this reason, it is possible to execute an optimal correction process according to the print format by combining and printing as necessary.

  In addition to the above-described invention, another invention further includes a storage unit that stores a combination of a print format and a correction type, and the correction unit stores the image data based on the storage information of the storage unit. Correction is made. For this reason, by reading and processing the information stored in the storage means, the processing can be performed quickly and the contents of the processing executed by rewriting the information stored in the storage means can be easily changed. Is possible.

  Further, the present invention has a print head in which a plurality of nozzle rows formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and ink corresponding to image data to be printed is output from the nozzles. In a printing method for printing a desired image on a printing medium by discharging, a print format setting step for setting a print format and a correction process for image data corresponding to the print format set by the print format setting step And a supply step for supplying the image data corrected in the correction step to the corresponding nozzle rows.

  For this reason, even when the print head has an inclination, it is possible to perform optimum correction processing according to the print format.

  Another invention has a print head in which a plurality of nozzle arrays formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and nozzles corresponding to image data to be printed are nozzles In a computer-readable program that causes a computer to function to print a desired image on a print medium by ejecting from the printing medium, the printing format setting means for setting the printing format and the printing set by the printing format setting means A correction unit that performs a correction process on the image data in accordance with the format, and a supply unit that supplies the image data corrected by the correction unit to the corresponding nozzle array, respectively.

  For this reason, even when the print head has an inclination, it is possible to perform optimum correction processing according to the print format.

  According to the present invention, even when the print head is inclined, it is possible to perform optimum correction processing according to the print format.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  First, an outline of a printing apparatus according to an embodiment of the present invention will be described with reference to FIGS. In this specification, a combination of the printer 22 and the computer 90 is referred to as a “printing apparatus”.

  FIG. 1 is a schematic configuration diagram of the printer 22 constituting the printing apparatus, FIG. 2 is a diagram for explaining the details of the print head 12, and FIG. 3 shows the main part of the printer 22 with a control circuit 40 as a center. It is a block diagram which shows the example of a structure.

  As shown in FIG. 1, the printer 22 reciprocates a carriage 31 in the axial direction of the paper feed roller 26 by a sub-scan feed mechanism that transports a print paper P that is a printing medium by a paper feed motor 23 and a carriage motor 24. And a main scanning feed mechanism. Here, the feed direction of the printing paper P by the sub-scan feed mechanism is called a sub-scan direction, and the moving direction of the carriage 31 by the main scan feed mechanism is called a main scan direction.

  The printer 22 is mounted on the carriage 31 and includes a print head unit 60 including the print head 12, a head drive mechanism that drives the print head unit 60 to control ink ejection and dot formation, and these papers. A control circuit 40 that controls transmission / reception of signals to / from the feed motor 23, carriage motor 24, print head unit 60, and touch panel 32 is provided.

  Next, the configuration of the print head 12 will be described with reference to FIG.

  As shown in FIG. 1, the carriage 31 has a cartridge 71 containing dark yellow (DY) ink, a cartridge 72 containing light magenta (LM) ink, a cartridge 73 containing light cyan (LC) ink, Seven cartridges, a cartridge 74 containing black (K) ink, a cartridge 75 containing cyan (C) ink, a cartridge 76 containing magenta (M) ink, and a cartridge 77 containing yellow (Y) ink Ink cartridges 71 to 77 are detachably mounted.

  A print head 12 is provided below the carriage 31. In the print head 12, nozzles as ink discharge locations are arranged in a line in the transport direction of the printing paper P, and a nozzle line corresponding to each color ink is formed.

  FIG. 2 is a diagram illustrating the arrangement of the nozzles Nz in the print head 12. As shown in the drawing, the print head 12 has a length Ra in the main scanning direction and a length Rb in the sub scanning direction. The print head 12 includes eight nozzle rows A to H formed by arranging 180 nozzles Nz in a row in the sub-scanning direction and arranged in the main scanning direction. The nozzles Nz belonging to a pair of adjacent nozzle rows (for example, A and B) among the eight nozzle rows A to H are shifted from each other by a predetermined pitch in the sub-scanning direction, and every other row The nozzles Nz belonging to the nozzle row (for example, A and C) are arranged at the same position in the sub-scanning direction.

  In the print head 12 according to the present embodiment, the ink supplied to each of the eight nozzle rows A to H is a nozzle located on the center side of the print head 12 in the main scanning direction orthogonal to the sub-scanning direction. From the rows D and E to the nozzle rows A and H located on the end side, the color changes from dark to light.

  Specifically, a black ink is ejected from a pair of adjacent nozzle rows D and E located at the center of the print head 12 in the main scanning direction, and a pair of nozzles located outside these nozzle rows D and E. Cyan ink is ejected from the nozzle arrays C and F, and magenta ink is ejected from the pair of nozzle arrays B and G located outside the nozzle arrays C and F. Yellow ink is ejected from a pair of nozzle rows A and H located adjacent to the outside.

  Here, the black ink is black ink (K), the cyan ink is cyan ink (C) or light cyan ink (LC), and the magenta ink is magenta ink (M) or light magenta ink (LM). The yellow ink is yellow ink (Y) or dark yellow ink (DY).

  A piezoelectric element that is one of electrostrictive elements and excellent in responsiveness is arranged for each nozzle in a nozzle row that is provided below the carriage 31 and is associated with each ink. The piezo element is installed at a position in contact with a member that forms an ink passage that guides ink to the nozzle. Piezo elements have a crystal structure that is distorted by the application of voltage, and perform electro-mechanical energy conversion at an extremely high speed.

  In the present embodiment, by applying a voltage having a predetermined time width between the electrodes provided at both ends of the piezo element, the piezo element is extended for the voltage application time, and one side wall of the ink passage is deformed. As a result, the volume of the ink passage contracts according to the expansion of the piezo element, and the ink corresponding to the contraction becomes ink droplets and is ejected at high speed from the tip of the nozzle. The ink droplets soak into the printing paper P along the paper feed roller 26, whereby dots are formed and printing is performed. The size of the ink droplet can be changed by a method of applying a voltage to the piezo element. As a result, three types of dots having different sizes, large, medium, and small, can be formed.

  The control circuit 40 is connected to the computer 90 via the connector 56. The computer 90 is loaded with a printer driver program for the printer 22 as will be described later, accepts user commands by operating keyboards and mice as input devices, and displays various information in the printer 22 on the screen of the display device. It constitutes a user interface to be presented by display.

  The sub-scan feed mechanism that transports the printing paper P includes a gear train (not shown) that transmits the rotation of the paper feed motor 23 to a paper feed roller 26 and a paper transport roller (not shown).

  The main scanning feed mechanism for reciprocating the carriage 31 is an endless drive between the carriage motor 24 and a slide shaft 34 that is laid in parallel with the axis of the paper feed roller 26 and slidably holds the carriage 31. A pulley 38 for stretching the belt 36 and an optical sensor 39 for detecting the origin position of the carriage 31 are provided. The optical sensor 39 includes a light source that projects light onto the printing paper P, and a photodiode (or a CCD element) that converts reflected light from the printing paper P into an image signal corresponding thereto. Yes.

  As shown in FIG. 3, the control circuit 40 includes a CPU (Central Processing Unit) 41, a programmable ROM (P-ROM (Read Only Memory)) 43, a RAM (Random Access Memory) 44, and a character that stores a dot matrix of characters. It is configured as an arithmetic and logic circuit including a generator (CG (Character Generator)) 45, an EEPROM (Electronically Erasable and Programmable ROM) 46, and an encoder 47. The encoder 47 detects the position of the carriage 31 in the main scanning direction based on the detection signal from the detection unit 48 provided in the carriage motor 24. The encoder 47 detects the position of the printing paper P in the sub-scanning direction based on the detection signal from the detection unit 49 provided in the paper feed motor 23.

  The control circuit 40 further drives an I / F dedicated circuit 50 that is an interface (I / F (Interface)) with an external motor or the like, and the print head unit 60 connected to the I / F dedicated circuit 50. A head drive circuit 52 that ejects ink, and a motor drive circuit 54 that drives the paper feed motor 23 and the carriage motor 24.

  The I / F dedicated circuit 50 incorporates a parallel interface circuit and can receive print data PD supplied from the computer 90 via the connector 56.

  Next, the configuration of the computer 90 will be described with reference to FIG.

  As shown in FIG. 4, the computer 90 includes a CPU 91, ROM 92, RAM 93, HDD (Hard Disk Drive) 94, video circuit 95, I / F 96, bus 97, display device 98, input device 99, and external storage device 100. Has been.

  Here, the CPU 91, which is a print format setting unit, a correction unit, and a part of the supply unit, executes various arithmetic processes according to programs stored in the ROM 92 and the HDD 94, and controls each unit of the apparatus. It is a control unit.

  The ROM 92 is a memory that stores basic programs executed by the CPU 91 and data. The RAM 93 is a memory that temporarily stores programs being executed by the CPU 91 and data being calculated.

  In response to a request from the CPU 91, the HDD 94 serving as storage means reads out data and programs recorded on the hard disk serving as a recording medium, and records data generated as a result of the arithmetic processing of the CPU 91 onto the hard disk described above. Device.

  The video circuit 95 is a circuit that executes a drawing process in accordance with a drawing command supplied from the CPU 91, converts the obtained image data into a video signal, and outputs the video signal to the display device 98.

  The I / F 96 that is a part of the supply unit is a circuit that appropriately converts the expression format of the signals output from the input device 99 and the external storage device 100 and outputs the print data PD to the printer 22.

  The bus 97 is a signal line that connects the CPU 91, the ROM 92, the RAM 93, the HDD 94, the video circuit 95, and the I / F 96 to each other and enables data exchange between them.

  The display device 98 is configured by, for example, an LCD (Liquid Crystal Display) monitor or a CRT (Cathode Ray Tube) monitor, and displays an image corresponding to the video signal output from the video circuit 95.

  The input device 99 is configured by, for example, a keyboard and a mouse, and is a device that generates a signal corresponding to a user operation and supplies the signal to the I / F 96.

  The external storage device 100 includes, for example, a CD-ROM (Compact Disk-ROM) drive unit, an MO (Magneto Optic) drive unit, and an FDD (Flexible Disk Drive) unit, and is recorded on a CD-ROM disc, an MO disc, and an FD. This is a device that reads out data and programs that are stored and supplies them to the CPU 91. In the case of the MO drive unit and the FDD unit, the data is supplied from the CPU 91 to the MO disk or FD.

  FIG. 5 is a diagram for explaining functions of programs and drivers installed in the computer 90. Note that these functions are realized by the cooperation of the hardware of the computer 90 and the software recorded in the HDD 94. As shown in this figure, an application program 201, a video driver program 202, and a printer driver program 210 are installed in a computer 90, and these operate under a predetermined operating system (OS).

  Here, the application program 201 is, for example, an image processing program, which processes an image captured from a digital camera or the like or processes an image drawn by a user, and then processes the printer driver program 210 and the video. Output to the driver program 202.

  The video driver program 202 is a program for driving the video circuit 95. For example, the video driver program 202 generates a video signal after performing gamma processing, white balance adjustment, or the like on the image data supplied from the application program. It is supplied to the display device 98 and displayed.

  The printer driver program 210 includes a resolution conversion module 211, a color conversion module 212, a color conversion table 213, a halftone module 214, a recording rate table 215, a print data generation module 216, and a raster data adjustment module 217. Various processing described later is performed on the image data generated by the application program 201 to generate print data PD, which is supplied to the printer 22.

  Here, the resolution conversion module 211 is a program executed when processing for converting the resolution of the image data supplied from the application program 201 in accordance with the resolution of the print head 12 is performed.

  The color conversion module 212 refers to the color conversion table 213 for image data expressed in an RGB (Red, Green, Blue) color system, and an image in a CMYK (Cyan, Magenta, Yellow, Black) color system. It is a program that is executed when performing processing for conversion to data.

  The halftone module 214 converts the image data represented by the CMYK color system into bitmap data composed of a combination of three types of large, medium, and small dots with reference to the recording rate table 215 by dither processing. It is a program that is executed when

  The print data generation module 216 generates print data PD including raster data indicating the dot recording state during each main scan and data indicating the sub-scan feed amount from the bitmap data output from the halftone module 214. Thus, the program is executed when the printer 22 is supplied.

  The raster data adjustment module 217 adjusts the position of the raster data in the main scanning direction and the sub-scanning direction according to the amount of inclination of the print head 12 to prevent image deterioration due to the inclination of the print head 12. It is a program to be executed.

  Next, the operation of the embodiment of the present invention will be described.

  First, when the input device 99 of the computer 90 is operated and, for example, it is instructed to start the application program 201 for editing image data, the CPU 91 of the computer 90 loads the application program 201 stored in the HDD 94. Read and execute.

  When an instruction to print image data created by the application program 201 is given, a flowchart as shown in FIG. 6 is started. When this flowchart is started, the following steps are executed.

  Step S10: The CPU 91 displays a setting screen 250 as shown in FIG. On this screen 250, a title 251, setting items 252 to 255, and buttons 256 and 257 are displayed.

  Here, the title 251 is the title of this screen 250, and “print mode setting” is displayed in this example. The setting item 252 is for setting a color mode, and is either a four-color mode (C, M, Y, K) or a seven-color mode (C, M, Y, K, LC, LM, DY). Select one with the radio buttons. A setting item 253 is used to set a print mode, and selects either high-speed printing or high-resolution printing with a radio button. A setting item 254 is used to set a printing paper, and selects either plain paper or high-quality paper using a radio button. The setting item 255 is used to set the type of ink (black ink) to be used, and either matte black or photo black is selected by a radio button.

  The button 256 is operated when the content input on the screen 250 is confirmed, and the button 257 is operated when the content input on the screen 250 is canceled.

  In the example shown in FIG. 7, “7-color mode”, “high-speed printing”, “quality paper”, and “matte black” are selected by radio buttons.

  Step S11: The CPU 91 acquires the setting contents input on the screen 250 shown in FIG.

  Step S12: The CPU 91 specifies the type of correction with reference to the tables shown in FIGS. The table shown in FIG. 9 is a table that is referred to when a non-text such as a natural image is printed, and shows the relationship between the color mode, the print mode, and the printing paper and the type of correction.

  Here, the relationship between each mode and the type of correction will be described. First, regarding the color mode, when the color mode is 7 colors, as shown in FIG. 1, nozzles for light-colored ink are arranged at both ends of the print head 12. The light-colored ink does not stand out even if it is slightly deviated from the normal position, and therefore has little influence on the image quality. On the other hand, when the color mode is four colors, there are no light-colored nozzles, so the inclination of the print head 12 appears as a deterioration in image quality. Therefore, it is more necessary to correct the inclination of the print head 12 when the color mode is four colors.

  As for the print mode, when the print mode is the high resolution mode, it is necessary to eliminate the influence of the inclination of the print head 12 and to make the image quality as high as possible. Therefore, the necessity for correction is higher in the high resolution mode.

  As for printing paper, in the case of plain paper, dots often bleed due to capillarity, so the deterioration in image quality due to dot misalignment is not as pronounced as that of high-quality paper. Therefore, high-quality paper has a higher need for correction.

  The correction in the sub-scanning direction can be corrected by simple processing because the raster data of each nozzle is merely shifted in the sub-scanning direction by a predetermined amount, as will be described later. Since it is necessary to perform correction processing in units of one scanning line, the load is large, and the correction effect is not so remarkable for the load.

  FIG. 8 is an example of a table showing the types of correction in natural images determined according to the characteristics of each mode as described above and the cost effectiveness of each correction.

  Specifically, when the color mode is the four-color mode, the printing mode is high resolution, and the printing paper is high-quality paper, both correction in the main scanning direction and correction in the sub-scanning direction are performed. When the color mode is the 7-color mode, the print mode is high resolution, and the printing paper is high-quality paper, only correction in the sub-scanning direction is performed. When the color mode is the four-color mode, the printing mode is high-speed printing, and the printing paper is high-quality paper, only correction in the sub-scanning direction is performed. When the color mode is the 7-color mode, the printing mode is high-speed printing, and the printing paper is high-quality paper, only correction in the sub-scanning direction is performed. When the color mode is the four-color mode, the printing mode is high-speed printing, and the printing paper is plain paper, no correction is performed. When the color mode is the 7-color mode, the printing mode is high-speed printing, and the printing paper is high-quality paper, only correction in the sub-scanning direction is performed. When the color mode is the 7-color mode, the printing mode is high-speed printing, and the printing paper is plain paper, no correction is performed.

  FIG. 9 is an example of a table used when printing text. In this example, the type of correction is determined according to the print mode, print paper, and ink type. Here, the printing mode and the printing paper are the same as those in FIG. The ink type indicates the type of black ink, and matte black is ink used when printing text, and is distinguished from photo black used when printing a photograph.

  In this example, when the printing mode is high resolution, the printing paper is high-quality paper, and the ink type is matte black, both the main scanning direction and the sub-scanning direction are corrected. When the printing mode is high-speed printing, the printing paper is high-quality paper, and the ink type is matte black, only correction in the sub-scanning direction is performed. Further, no correction is performed when the printing mode is high-speed printing, the printing paper is plain paper, and the ink type is matte black.

  Step S13: The CPU 91 supplies image data to the printer driver program 210 based on the application program 201, and generates raster data.

  Specifically, the image data generated by the processing by the application program 201 is first converted into a resolution corresponding to the print head 12 based on the resolution conversion module 211. Next, the image data whose resolution has been converted based on the resolution conversion module 211 is converted from the image data expressed in the RGB color system into image data in the CMYK color system based on the color conversion module 212. Conversion is performed with reference to 213. Next, based on the halftone module 214, the image data represented by the CMYK color system by dither processing is referred to the recording rate table 215, and consists of a combination of three types of large, medium, and small dots. Converted to bitmap data. Then, based on the print data generation module 216, printing including raster data indicating the dot recording state during each main scan and data indicating the sub-scan feed amount from the bitmap data output from the halftone module 214. Data PD is generated.

  Step S <b> 14: Based on the raster data adjustment module 217, the CPU 91 acquires information related to the tilt amount of the print head 12 stored in the P-ROM 43 of the printer 22.

  Here, the information regarding the amount of tilt is that, as shown in FIG. 10, if the print head 12 is mounted in a scan plane inclined at an angle α in the counterclockwise direction, as shown in FIG. 12 is a moving distance dy of the upper right end portion of 12 and a moving distance dx of the lower left end portion of the print head 12 as shown in FIG. These pieces of information are obtained by measuring the print head 12 and stored in the P-ROM 43 in advance.

  Step S15: The CPU 91 acquires the print resolution of the image data to be printed from the application program 201 based on the raster data adjustment module 217. For example, 1440 dpi (dots per inch) is acquired as the print resolution.

  Step S <b> 16: The CPU 91 acquires raster data for a predetermined nozzle row based on the raster data adjustment module 217. For example, the raster data of the H column shown in FIG. 2 is acquired.

  Step S17: The CPU 91 refers to the tables shown in FIG. 8 and FIG. 9 to determine whether or not to perform correction in the sub-scanning direction, and proceeds to step S18 when performing correction, and otherwise proceeds to step S18. Proceed to S19.

  Step S18: The CPU 91 executes “raster correction processing in the sub-scanning direction”, which is processing for correcting the raster position in the sub-scanning direction, based on the raster data adjustment module 217. Details of this processing will be described later with reference to FIG.

  Step S19: The CPU 91 refers to the tables shown in FIG. 8 and FIG. 9 to determine whether or not correction in the main scanning direction is to be performed. If correction is to be performed, the process proceeds to step S20. Proceed to S21.

  Step S20: The CPU 91 executes “raster correction processing in the main scanning direction” which is processing for correcting the position of the raster in the main scanning direction based on the raster data adjustment module 217. Details of this processing will be described later with reference to FIG.

  Step S21: Based on the raster data adjustment module 217, the CPU 91 determines whether or not the processing for all raster data has been completed. If completed, the CPU 91 proceeds to step S22, otherwise returns to step S17. Repeat the same process.

  Step S22: The CPU 91 supplies a predetermined command to the printer 22 based on the printer driver program 210, and starts paper feed processing. As a result, in the printer 22, the control circuit 40 receives this command, drives the paper feed motor 23, and feeds only one print paper P from a stocker (not shown).

  Step S23: The CPU 91, for example, compresses the raster data subjected to the raster correction processing in the sub-scanning direction and the main scanning direction based on the printer driver program 210, and then transmits the raster data to the printer 22. In the printer 22, the control circuit 40 receives the compressed raster data and executes decompression processing.

  Step S24: The CPU 91 requests the printer 22 to print the raster data transmitted in step S18 based on the printer driver program 210. As a result, in the printer 22, the control circuit 40 applies a driving voltage to the print head 12 to eject ink droplets while reciprocating the carriage motor 24 in the main scanning direction. When the printing of one scanning line is completed, the control circuit 40 drives the paper feed motor 23 to perform sub-scanning. Thereafter, the printing of the image is completed by repeating the same operation.

  Step S25: Based on the printer driver program 210, the CPU 91 executes a process of discharging the printing paper P that has been printed. As a result, in the printer 22, the control circuit 40 drives the paper feed motor 23 to execute a process of discharging the printing paper P that has been printed.

  Next, the details of the “sub-scanning direction raster correction process” shown in step S18 of FIG. 6 will be described with reference to FIG. When this process is executed, the following steps are executed.

  Step S30: Based on the raster data adjustment module 217, the CPU 91 calculates dyi, which is a shift amount in the sub-scanning direction of the target nozzle row. That is, as shown in FIG. 14, when the print head 12 has an inclination α in the counterclockwise direction and the target nozzle row is G, there is no inclination. The dyi that is the difference between the nozzle position (in this example, the nozzle position of the nozzle row A) and the current nozzle position is obtained.

Specifically, as shown in FIG. 11, if the distance to the target nozzle row is Rai, the target dyi is obtained by the following equation.
dyi = dy × Rai / Ra (Formula 1)

  Step S31: The CPU 91 acquires the print resolution pr based on the raster data adjustment module 217. Specifically, 1440 dpi is acquired as the print resolution pr based on the raster data adjustment module 217.

  Step S32: Based on the raster data adjustment module 217, the CPU 91 calculates a dot shift amount Ddy in the sub-scanning direction of raster data corresponding to the target nozzle row. Specifically, as shown in the following equation, the dot displacement amount Ddy is calculated by multiplying dyi obtained in step S30 by the print resolution pr obtained in step S31. Here, round () is a function that rounds off the first decimal place.

  Ddy = round (dyi × pr) (Equation 2)

  Step S32: The CPU 91 moves the raster data in the sub-scanning direction by the shift amount Ddy based on the raster data adjustment module 217, and returns to the original processing. In the example of FIG. 14, the raster data 251 is moved by one dot (Ddy = 1), and the raster data 252 is different only in the position in the sub-scanning direction.

  Next, the details of the “main scanning direction raster correction process” shown in step S14 of FIG. 6 will be described with reference to FIG. When this process is executed, the following steps are executed.

  Step S50: The CPU 91 acquires the print resolution pr based on the raster data adjustment module 217. Specifically, 1440 dpi is acquired as the print resolution.

  Step S51: The CPU 91 acquires raster data for one scanning line based on the raster data adjustment module 217. Specifically, in the case of the print head 12 shown in FIG. 2, since one scan line is composed of 180-dot data in the sub-scan direction, the width in the sub-scan direction is 180 as data for one scan line. Acquire rectangular raster data that is dots.

Step S52: Based on the raster data adjustment module 217, the CPU 91 calculates dxi, which is a shift amount of each nozzle in the main scanning direction. That is, as shown in FIG. 12, if the distance to the target nozzle row is Rbi, the target dxi is obtained by the following equation.
dxi = dx × Rbi / Rb (Formula 3)

  Step S53: Based on the raster data adjustment module 217, the CPU 91 calculates a dot shift amount Ddx in the main scanning direction of raster data corresponding to each nozzle. Specifically, as shown in the following equation, the shift amount Ddx of each dot is calculated by multiplying dxi obtained in step S52 by the print resolution pr acquired in step S50. Here, round () is a function that rounds off the first digit of the decimal point.

  Ddx = round (dxi × pr) (Formula 4)

  Step S54: Based on the raster data adjustment module 217, the CPU 91 moves each raster data constituting the main scan line by the shift amount Ddx in the main scan direction. Specifically, as shown in FIG. 16A, when the print head 12 is inclined by the angle α, the printed dots have the same inclination. Therefore, the raster data before adjustment as shown in FIG. 16B is converted into Ddx for each raster in the direction opposite to the direction in which the print head 12 is inclined, as shown in FIG. Just move. In this example, the lines from the first line to the third line are left as they are, the lines from the fourth line to the sixth line are moved to the right by one dot, and the lines from the seventh line to the sixth line are moved. The 9th line is moved 2 dots to the right of the figure.

  As a result, when printing is performed using raster data that has been adjusted in this way, in the raster data of FIG. 16B, the dot groups arranged in one line in the sub-scanning direction are the same as those in FIG. As shown in (D), they are almost arranged on a straight line in the sub-scanning direction.

  Step S55: The CPU 91 determines based on the raster data adjustment module 217 whether or not the processing of all the scanning lines has been completed, and if completed, returns to the original processing; Returning to S51, the same processing is repeated.

  According to the above processing, when the print head 12 has an inclination, it is possible to print an image or the like by executing an optimal correction by selecting a correction type according to the print format. It becomes possible.

  Although one embodiment of the present invention has been described above, the present invention can be variously modified in addition to this. For example, in the above embodiment, seven colors of DY, LM, LC, K, C, M, and Y are used as the ink, but other ink combinations may be used.

  In the above embodiment, the printer 22 having a head for ejecting ink using a piezo element is used. However, various ejection drive elements other than the piezo element can be used. is there. For example, the present invention can be applied to a printer provided with an ejection drive element of a type that energizes a heater disposed in an ink passage and ejects ink by bubbles generated in the ink passage.

  In the above embodiment, the process shown in FIG. 6 is always executed regardless of the magnitude of the inclination amount of the print head 12. For example, the inclination acquired in step S14 shown in FIG. If the amount is less than a certain amount, the processing may be terminated and the processing after step S16 may be omitted. According to such a method, unnecessary processing can be omitted and processing can be speeded up.

  Also, a plurality of tables shown in FIGS. 8 and 9 may be prepared so that an optimum table can be selected according to the amount of inclination of the print head 12. According to such a method, it is possible to perform an optimal correction process according to the inclination of the print head 12.

  Further, in the above embodiment, the printing paper types are two types of plain paper and high-quality paper, but it may be determined by adding other types of printing paper. For example, in the case of long paper such as roll paper or bellows paper, it is often used on the premise that a large number of images are printed, so when such printing paper is used In order to speed up the processing, for example, correction in the main scanning direction that requires time for processing can be omitted and only correction in the sub-scanning direction that does not require time for processing can be performed.

  Further, the tables shown in FIGS. 8 and 9 are examples, and the present invention is not limited only to such a case, and it goes without saying that various modified embodiments exist.

  In the above embodiment, the natural image and the text are handled separately, but it is also possible to handle them together, for example. By doing so, it is possible to speed up the processing by making a judgment collectively without making a judgment individually.

  In the above embodiment, the computer 90 executes the processes shown in FIGS. 6, 13, and 15, but part or all of these can also be executed by the printer 22. . In that case, the processing shown in FIGS. 6, 13, and 15 may be appropriately executed by using a predetermined button on the touch panel 32 as a trigger.

In the above embodiment, the displacement amount dxi is calculated using the distance Rai from the reference nozzle row (nozzle row A in this example) and dy. For example, the angle α And Rai and may be calculated using a trigonometric function. Specifically, dyi is obtained by the following equation.
dyi = Rai × tan α (Formula 5)

Further, in the above embodiment, the shift amount dxi is calculated using the distance Rbi from the reference nozzle (nozzle N _{1 in} this example) and dx, but for example, the angle α and , Rbi and may be calculated using a trigonometric function. Specifically, dxi is obtained by the following equation.
dxi = Rbi × tan α (Formula 6)

  The program describing the above processing functions can be recorded on a computer-readable recording medium. Examples of the computer-readable recording medium include a magnetic recording device, an optical disk, a magneto-optical recording medium, and a semiconductor memory. Examples of the magnetic recording device include a hard disk device (HDD), a flexible disk (FD), and a magnetic tape. Optical disks include DVD, DVD-RAM (Random Access Memory), CD-ROM, CD-R (Recordable) / RW (ReWritable), and the like. Magneto-optical recording media include MO.

  When distributing the program, for example, a portable recording medium such as a DVD or a CD-ROM in which the program is recorded is sold. It is also possible to store the program in a storage device of a server computer and transfer the program from the server computer to another computer via a network.

  The computer that executes the program stores, for example, the program recorded on the portable recording medium or the program transferred from the server computer in its own storage device. Then, the computer reads the program from its own storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing according to the program. In addition, each time the program is transferred from the server computer, the computer can sequentially execute processing according to the received program.

  The present invention has a print head in which a plurality of nozzle rows formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and ejects ink corresponding to image data to be printed from the nozzles. By this, it can utilize for the printing apparatus which has a print head which prints a desired image on a printing medium.

1 is a diagram illustrating a schematic configuration of a main part of a printing apparatus according to an embodiment. It is a figure which shows the structure of the print head of the printer shown in FIG. FIG. 2 is a block diagram illustrating a detailed configuration example of a control circuit of the printer illustrated in FIG. 1. It is a block diagram which shows the detailed structural example of the computer shown in FIG. FIG. 5 is a diagram illustrating an example of functions realized by cooperation of hardware and software in the computer illustrated in FIG. 4. FIG. 2 is a diagram for explaining an example of processing executed in the printing apparatus shown in FIG. 1. 2 is an example of a print format setting screen displayed when an image is printed in the printing apparatus illustrated in FIG. 1. FIG. 2 is a diagram illustrating a relationship between a printing format and a type of correction that is stored in the printing apparatus illustrated in FIG. 1 and is referred to when a natural image is printed. FIG. 2 is a diagram illustrating a relationship between a printing format and a correction type that is referred to when printing text stored in the printing apparatus illustrated in FIG. 1. It is a figure which shows a mode when the printing head of the printer shown in FIG. 1 is attached in the state inclined. FIG. 2 is a diagram illustrating an inclination in a sub-scanning direction when the print head of the printer shown in FIG. 1 is attached in an inclined state. It is a figure which shows the inclination of the main scanning direction when the print head of the printer shown in FIG. 1 is attached in the state inclined. 7 is a flowchart for explaining details of “raster correction processing in the sub-scanning direction” in the flowchart shown in FIG. 6. FIG. 6 is a diagram illustrating a relationship between the inclination of the print head and the movement of raster data in the sub-scanning direction. 7 is a flowchart for explaining details of “raster correction processing in the main scanning direction” in the flowchart shown in FIG. 6. FIG. 4 is a diagram illustrating a relationship between the inclination of a print head and the movement of raster data in the main scanning direction. FIG. 6 is a diagram illustrating a shift of dots in the sub-scanning direction caused by the inclination of the print head. FIG. 4 is a diagram illustrating a shift of dots in a main scanning direction caused by a tilt of a print head.

Explanation of symbols

22 Printer (part of printing device)
90 Computer (part of printing device)
91 CPU (print format setting means, correction means, part of supply means)
94 HDD (storage means)
96 I / F (part of supply means)
P Printing paper (printing medium)

Claims (8)

By having a print head in which a plurality of nozzle rows formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and ejecting ink corresponding to image data to be printed from the nozzles, In a printing apparatus that prints a desired image on a print medium,
Conversion means for converting the image data into raster data corresponding to each nozzle;
Print format setting means for setting the print format;
Correction means for executing correction processing for adjusting the position of the raster data corresponding to each nozzle row in the sub-scanning direction according to the amount of inclination of the print head ;
Supply means for supplying the raster data corrected by the correction means to the corresponding nozzle rows;
Have
The correction means adjusts the position of the raster data in the sub-scanning direction when the printing format is the first printing format, and sub-scans the raster data when the printing format is the second printing format. A printing apparatus characterized by not adjusting the position in the direction . The correction unit adjusts the position of the raster data corresponding to each nozzle row in the main scanning direction for each raster line according to the tilt amount of the print head, and the print format is the third print format. The printing apparatus according to claim 1, further comprising: adjusting the position of the raster data in the main scanning direction after adjusting the position of the raster data in the sub-scanning direction.   3. The printing apparatus according to claim 1, wherein the printing format setting unit sets the type of printing medium, the printing resolution, or the type of ink as a printing format. Printing apparatus according to any one of claims 1 to claim 3 for ejecting the ink by using a piezoelectric element. A printing apparatus having a print head in which a plurality of nozzle rows formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and ejecting ink corresponding to image data to be printed from the nozzles In a printing method for printing a desired image on a print medium,
A conversion step of converting the image data into raster data corresponding to each nozzle;
A print format setting step for setting the print format;
A correction step of executing a correction process for adjusting the position of the raster data corresponding to each nozzle row in the sub-scanning direction according to the inclination amount of the print head ;
A supply step of supplying the raster data corrected by the correction step to the corresponding nozzle rows;
Have
In the correction step, when the printing format is the first printing format, the position of the raster data in the sub-scanning direction is adjusted, and when the printing format is the second printing format, the raster data is sub-scanned. A printing method characterized by not adjusting the position of the direction . In the correction step, the position of the raster data corresponding to each nozzle row in the main scanning direction is adjusted for each raster line according to the inclination amount of the print head, and the print format is the third print format. The printing method according to claim 5, further comprising: adjusting the position of the raster data in the main scanning direction after adjusting the position of the raster data in the sub-scanning direction. By having a print head in which a plurality of nozzle rows formed by arranging a plurality of nozzles in the sub-scanning direction are arranged in the main scanning direction, and ejecting ink corresponding to image data to be printed from the nozzles, In a computer-readable program that causes a computer to function to print a desired image on a print medium,
Computer
Conversion means for converting the image data into raster data corresponding to each nozzle;
Print format setting means for setting the print format,
Correction means for executing correction processing for adjusting the position of the raster data corresponding to each nozzle row in the sub-scanning direction according to the inclination amount of the print head ;
Supply means for supplying the raster data corrected by the correction means to the corresponding nozzle rows,
Function as
The correction means adjusts the position of the raster data in the sub-scanning direction when the printing format is the first printing format, and sub-scans the raster data when the printing format is the second printing format. A computer-readable program that does not adjust the position of the direction . The correction unit adjusts the position of the raster data corresponding to each nozzle row in the main scanning direction for each raster line according to the tilt amount of the print head, and the print format is the third print format. The program according to claim 7, further comprising: adjusting the position of the raster data in the main scanning direction after adjusting the position of the raster data in the sub-scanning direction.

Images