JP2006192636A - Liquid delivering system, liquid delivering apparatus, liquid delivering method, program and liquid delivering controlling apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve accuracy of an impacting position of a liquid on a medium even when a gap dimension between a nozzle and the medium is changed in relation to the moving direction of the nozzle. <P>SOLUTION: A liquid delivering system is equipped with (A) the nozzle delivering the liquid toward the medium while moving in a specified moving direction, (B) a memory storing information related to the gap dimension between the nozzle and the medium in accordance with the specified position in the moving direction, and (C) a controller determining a timing of delivering the liquid to the specified position based on the information, and making the timing of delivering the liquid to be a specified timing to at least several positions except the specified position. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

 The present invention relates to a liquid ejection system, a liquid ejection apparatus, a liquid ejection method, a program, and a liquid ejection control apparatus that eject liquid toward a medium while moving a nozzle in a predetermined movement direction.

A liquid discharge system (for example, an ink jet printer) that discharges liquid toward a medium while moving a nozzle in a predetermined movement direction is known (see Patent Document 1).
In this liquid ejection system, the medium is supported by a plurality of support portions provided at different positions along the moving direction. For this reason, the liquid that does not land on the medium can be thrown away into the recess that is a part other than the support portion, and the back surface of the medium does not have to be stained with the liquid.
JP 2002-86693 A

  However, with such a configuration, the medium supported by the plurality of support portions has a wavy shape along the moving direction, and the gap dimension between the nozzle and the medium varies in the moving direction. As a result, there is a possibility that the landing position of the liquid ejected from the nozzle during the movement in the moving direction is different, and the image quality of the image printed on the medium may be deteriorated.

  The present invention has been made in view of such circumstances, and an object thereof is to provide the medium even when the gap dimension between the nozzle and the medium varies with respect to the moving direction. An object of the present invention is to realize a liquid ejection system, a liquid ejection apparatus, a liquid ejection method, a program, and a liquid ejection control apparatus capable of improving the landing position accuracy of the above liquid.

The main invention for achieving the object is as follows:
(A) a nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
(B) a memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
(C) a controller that determines a liquid discharge timing for the predetermined position based on the information, and sets a liquid discharge timing as a predetermined timing for at least some positions other than the predetermined position;
A liquid discharge system including (D).

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

=== Summary of disclosure ===
At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

(A) a nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
(B) a memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
(C) a controller that determines a liquid discharge timing for the predetermined position based on the information, and sets a liquid discharge timing as a predetermined timing for at least some positions other than the predetermined position;
A liquid ejection system comprising (D).

According to such a liquid ejection system, the memory stores information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the movement direction. Based on this information, the liquid ejection timing for the predetermined position is determined.
Therefore, if a position having a large deviation from the design value of the gap dimension is made to correspond to the predetermined position, even if the gap dimension greatly fluctuates with respect to the movement direction, the liquid that may be generated due to the gap is changed. The error of the landing position can be suppressed small, and as a result, the liquid landing position accuracy can be increased.

In such a liquid ejection system,
The position where the ejection timing is determined based on the information is preferably over a predetermined range including the predetermined position.

According to such a liquid ejection system, it is possible to improve the liquid landing position accuracy with respect to positions around the predetermined position.
That is, when the gap size at the predetermined position is greatly deviated from the design value, there is a high probability that the gap size at the surrounding position is also greatly deviated from the design value. Also for a predetermined range including the predetermined position, the discharge timing is determined based on the information. Therefore, even for a position within the predetermined range, it is possible to suppress a liquid landing position error that may occur due to the gap size variation, and as a result, it is possible to improve the liquid landing position accuracy.

In such a liquid ejection system,
A plurality of support portions are provided along the moving direction to support the medium, and a gap dimension between the support portion and the nozzle is the same across the plurality of support portions,
The predetermined position is preferably an intermediate position between the support portions adjacent to each other.
According to such a liquid ejection system, the predetermined position is designated as an intermediate position between the support portion and the support portion, where the deviation from the design value of the gap dimension between the nozzle and the medium tends to be the largest. Yes. Therefore, the effect of suppressing the error of the landing position made by the information can be most effectively exhibited.

In such a liquid ejection system,
The gap dimension between the portion of the medium contacting the support portion and the nozzle is a design value of the gap dimension,
The information is preferably a deviation of the gap size at the predetermined position from the design value.
According to such a liquid ejection system, the information is set as a deviation from a design value based on a gap dimension between the portion of the medium in contact with the support portion and the nozzle. Therefore, the landing position accuracy equivalent to the portion where the gap dimension is the design value can be obtained even at the predetermined position.

In such a liquid ejection system,
The controller ejects liquid based on image data input to the controller,
It is desirable for the controller to advance the liquid ejection timing by an amount based on the information with respect to a position within a predetermined range including the intermediate position, rather than the timing at which the liquid is ejected based on the image data.

According to such a liquid ejection system, it is possible to improve the liquid landing position accuracy with respect to a position within a predetermined range including the intermediate position.
That is, since the portion of the medium in the vicinity of the intermediate position is not supported by the support portion, the gap size between the nozzle and the medium is large. For this reason, if the liquid is directly ejected to the portion based on the image data, it will land after being delayed by an amount corresponding to the large gap size, resulting in landing on the downstream side of the moving direction from the target position. . Here, in the liquid ejection system, the liquid is ejected earlier by the amount based on the information than the timing of ejection based on the image data, so that the landing position accuracy is improved by compensating for the landing delay. Can do.

In such a liquid ejection system,
The nozzle is movable in both directions of the moving direction,
The controller causes the liquid to be ejected from the nozzle with the intermediate position as a target position in both the bidirectional forward path and the backward path,
It is desirable to obtain the information based on the deviation of the actual landing positions of the liquid in the forward path and the return path.
According to such a liquid ejection system, the information is obtained based on the deviation of the actual landing position between the forward path and the backward path, so that the information can be easily and reliably acquired, and is excellent in convenience.

In such a liquid ejection system,
The medium is a flexible sheet;
When the sheet body is supported by the plurality of support portions, the sheet body is deformed such that a portion corresponding to the support portion has a mountain shape and a portion corresponding to the intermediate position has a valley shape. Is desirable.
According to such a liquid ejection system, it is possible to most effectively enjoy the effect of suppressing the landing position error made by the information.

In such a liquid ejection system,
The memory preferably stores information on the gap size for each type of the medium.
According to such a liquid ejection system, it is possible to improve the liquid landing position accuracy for any type of medium. That is, in general, if the type of medium is different, the state of fluctuation of the gap dimension in the moving direction also changes. However, if the information is provided for each type of medium, the optimum position error can be suppressed. The information can be stored for each medium. As a result, the liquid can be discharged at an optimal discharge timing according to the type of the medium, and the landing position accuracy of the liquid can be improved regardless of the type of the medium.

In such a liquid ejection system,
The liquid is ink;
The liquid ejection system is preferably a printing system that forms an image on the medium.
According to such a liquid ejection system, a printing system with high ink landing position accuracy can be provided, and a high-quality image can be printed on a medium.

In such a liquid ejection system,
The nozzle is movable in both directions with respect to the moving direction;
The nozzle preferably discharges the liquid both in the bidirectional forward path and in the backward path.
According to such a liquid ejection system, a high-quality image can be printed on a medium by bidirectional printing. Further, the macroscopic influence of the landing position error on the image quality, that is, the deterioration of the apparent image quality, tends to be more noticeable in bidirectional printing than in unidirectional printing, but it is possible to effectively suppress the deterioration. it can.

(A) a nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
(B) a memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
(C) a controller that determines a liquid discharge timing for the predetermined position based on the information, and sets a liquid discharge timing as a predetermined timing for at least some positions other than the predetermined position;
A liquid ejection system comprising (D),
The position for determining the ejection timing based on the information is over a predetermined range including the predetermined position,
A plurality of support portions are provided along the moving direction to support the medium, and a gap dimension between the support portions and the nozzles is the same across the plurality of support portions, and the predetermined position Is an intermediate position between the support portions adjacent to each other,
The gap dimension between the portion of the medium contacting the support and the nozzle is a design value of the gap dimension, and the information is a deviation from the design value of the gap dimension at the predetermined position,
The controller discharges liquid based on image data input to the controller, and the controller sets the liquid discharge timing to the image data for a position within a predetermined range including the intermediate position. Earlier than the timing of ejection based on the information,
The nozzle is movable in both directions of the movement direction, and the controller discharges liquid from the nozzle with the intermediate position as a target position in both of the bidirectional forward path and the return path, respectively. Obtain the information based on the deviation of the actual landing position of the liquid in the forward and return paths,
The medium is a flexible sheet body, and when the sheet body is supported by the plurality of support portions, a portion corresponding to the support portion of the sheet body has a mountain shape and is located at the intermediate position. The corresponding part is deformed to form a valley,
The memory stores information on the gap size for each type of the medium,
The liquid is ink, and the liquid ejection system is a printing system that forms an image on the medium;
The liquid ejection system, wherein the nozzle ejects the liquid both in the bidirectional forward path and the backward path.
According to such a liquid ejection system, the effects of the present invention can be achieved most effectively because almost all the effects described above can be achieved.

A nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
A memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
A controller for determining a liquid discharge timing for the predetermined position based on the information, and a liquid discharge timing for at least some positions other than the predetermined position as a predetermined timing;
It is also possible to realize a liquid ejection device provided with

Also, a liquid ejection method for ejecting liquid from the nozzle toward the medium while moving the nozzle in a predetermined movement direction,
For the predetermined position in the movement direction, the liquid ejection timing is determined based on information on the gap size between the nozzle and the medium,
It is also possible to realize a liquid ejection method in which the liquid ejection timing is a predetermined timing for at least some positions other than the predetermined position.

A nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
A program that is executed in a liquid ejection system including a memory that stores information on a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction,
An implementation of a program comprising a step of determining a liquid ejection timing for the predetermined position based on the information and setting the liquid ejection timing as a predetermined timing for at least some positions other than the predetermined position. Is possible.

A nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
In a liquid ejection control apparatus for controlling a liquid ejection system provided with a memory that stores information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the movement direction,
A liquid discharge control apparatus that determines the liquid discharge timing for the predetermined position based on the information and sets the liquid discharge timing as the predetermined timing for at least some positions other than the predetermined position is also realized. Is possible.

=== Configuration of Printing System 100 ===
First, a printing system 100 as an example of a liquid ejection system will be described with reference to the drawings. However, the following description of the embodiment of the printing system 100 includes an embodiment related to a program and the like.

  FIG. 1 is an explanatory diagram showing an external configuration of the printing system 100. The printing system 100 includes a printer 1 and a computer 110. The printer 1 is a printing apparatus that prints an image on a medium such as paper, cloth, or film. The computer 110 is communicably connected to the printer 1 and outputs print data corresponding to the image to be printed to the printer 1 in order to cause the printer 1 to print an image. Since the computer 110 controls the printer 1 via the print data, it is also a liquid ejection control device.

  The printing system 100 further includes a display device 120, an input device 130, and a recording / reproducing device 140. The display device 120 has a display and displays a user interface such as the printer driver 116. The input device 130 is, for example, a keyboard 130A or a mouse 130B, and is used for operating the application program 114, setting the printer driver 116, or the like along the user interface displayed on the display device 120. As the recording / reproducing device 140, for example, a flexible disk drive device 140A or a CD-ROM drive device 140B is used.

  A printer driver 116 is installed in the computer 110. The printer driver 116 is a program for realizing the function of displaying the user interface on the display device 120 and the function of converting the image data output from the application program 114 into print data. The printer driver 116 is recorded on a recording medium (computer-readable recording medium) such as a flexible disk FD or a CD-ROM. Alternatively, the printer driver 116 can be downloaded to the computer 110 via the Internet. In addition, this program is comprised from the code | cord | chord for implement | achieving various functions.

=== Configuration of Printer 1 and Computer 110 ===
<Configuration of Printer 1 and Computer 110>
FIG. 2 is a block diagram of the overall configuration of the computer 110 and the printer 1 of the present embodiment. The computer 110 according to the present embodiment includes an interface unit 161, a CPU 162, and a memory 163.
The interface unit 161 is for transmitting and receiving data between the printer 110 as an external device and the computer 110. The CPU 162 is an arithmetic processing unit for controlling the entire computer 110. The memory 163 is a storage element that secures an area for storing a program such as the printer driver 116 and a work area. The CPU 162 generates print data from the image data according to the printer driver 116 stored in the memory 163 and transmits the print data to the printer 1. By installing the printer driver 116 in the computer 110, the CPU 162 and the memory 163 become a computer-side controller that controls the printer 1 via print data.

  The printer 1 of this embodiment includes a transport unit 20, a carriage unit 30, a head unit 40, a detector group 50, and a printer-side controller 60. The printer 1 that has received print data from the computer 110, which is an external device, controls each unit (conveyance unit 20, carriage unit 30, head unit 40) by the printer-side controller 60. The printer-side controller 60 controls each unit based on the print data received from the computer 110 and prints an image on the paper S. The situation in the printer 1 is monitored by the detector group 50, and the detector group 50 outputs the detection result to the printer-side controller 60. The printer-side controller 60 controls each unit based on the detection result output from the detector group 50.

  The printer-side controller 60 is a control unit for controlling the printer 1. The printer-side controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 is for transmitting and receiving data between the computer 110 which is an external device and the printer 1. The CPU 62 is an arithmetic processing unit for controlling the entire printer 1. The memory 63 is for securing an area for storing the program of the CPU 62, a work area, and the like, and has storage means such as a RAM and an EEPROM. The CPU 62 controls each unit via the unit control circuit 64 in accordance with a program stored in the memory 63.

  The computer controller (CPU 162 and memory 163) and the printer controller 60 are controllers that control the entire printing system 100. The printer driver 116 stored in the memory 163 on the computer side causes the computer 110 to generate print data and transmit the print data to the printer 1. On the other hand, the program stored in the memory 63 on the printer side causes the transport unit 20 to transport the paper S, moves the carriage 31 to the carriage unit 30, and causes the head unit 40 to eject ink according to the print data. For this reason, the printer driver 116 and the printer-side program cooperate with each other to cause the printing system 100 to perform printing.

  FIG. 3 is a schematic diagram of the overall configuration of the printer 1 of the present embodiment. FIG. 4 is a cross-sectional view of the overall configuration of the printer 1 of the present embodiment. Hereinafter, a basic configuration of the printer 1 of the present embodiment will be described.

  The transport unit 20 is for sending a medium (for example, the paper S) to a printable position and transporting the paper S by a predetermined transport amount in a predetermined direction (hereinafter referred to as a transport direction) during printing. The transport unit 20 includes a paper feed roller 21, a transport motor 22 (also referred to as a PF motor), a transport roller 23, a platen 24, and a paper discharge roller 25. However, in order for the transport unit 20 to function as a transport mechanism, all of these components are not necessarily required. The paper feed roller 21 is a roller for feeding the paper S inserted into the paper insertion slot into the printer 1. The paper feed roller 21 has a D-shaped cross section, and the length of the circumferential portion is set to be longer than the transport distance to the transport roller 23. Therefore, the paper S is transported using this circumferential portion. It can be conveyed to the roller 23. The transport motor 22 is a motor for transporting the paper S in the transport direction, and is configured by a DC motor, for example. The transport roller 23 is a roller that transports the paper S fed by the paper feed roller 21 to a printable area, and is driven by the transport motor 22. The platen 24 supports the paper S being printed. The paper discharge roller 25 is a roller for discharging the paper S to the outside of the printer 1 and is provided on the downstream side in the transport direction with respect to the printable area. The paper discharge roller 25 rotates in synchronization with the transport roller 23. The details of the platen 24 will be described later.

  The carriage unit 30 is for moving the head 41 in a predetermined direction (hereinafter referred to as a carriage movement direction). The carriage unit 30 includes a carriage 31 and a carriage motor 32 (hereinafter also referred to as a CR motor). The carriage 31 can reciprocate in the carriage movement direction, whereby the head 41 moves along the carriage movement direction. Further, the carriage 31 detachably holds an ink cartridge that stores ink. The carriage motor 32 is a motor for moving the carriage 31 in the carriage movement direction, and is constituted by a DC motor, for example.

  The head unit 40 is for ejecting ink onto the paper S. The head unit 40 has a head 41. The head 41 has a plurality of nozzles, and ejects ink intermittently from each nozzle. The head 41 is provided on the carriage 31. Therefore, when the carriage 31 moves in the carriage movement direction, the head 41 also moves in the carriage movement direction. Then, dot heads (raster lines) along the carriage movement direction are formed on the paper S by intermittently ejecting ink while the head 41 is moving in the carriage movement direction.

  The detector group 50 includes a linear encoder 51, a rotary encoder 52, a paper detection sensor 53, an optical sensor 54, and the like. The linear encoder 51 is for detecting the position of the carriage 31 in the carriage movement direction. The rotary encoder 52 is for detecting the rotation amount of the transport roller 23. The paper detection sensor 53 is for detecting the position of the leading edge of the paper S to be printed. The paper detection sensor 53 is provided at a position where the leading edge of the paper S can be detected while the paper supply roller 21 is feeding the paper S toward the transport roller 23. The paper detection sensor 53 is a mechanical sensor that detects the leading edge of the paper S by a mechanical mechanism. Specifically, the paper detection sensor 53 has a lever that can rotate in the transport direction, and this lever is disposed so as to protrude into the transport path of the paper S. Therefore, the leading edge of the paper S comes into contact with the lever, and the lever is rotated, so that the paper detection sensor 53 detects the position of the leading edge of the paper S by detecting the movement of the lever. The optical sensor 54 is attached to the carriage 31. The optical sensor 54 detects the presence or absence of the paper S when the light receiving unit detects reflected light of the light irradiated on the paper S from the light emitting unit. The optical sensor 54 can detect the position of the end portion of the paper S while being moved by the carriage 31, and can detect the width of the paper S. The optical sensor 54 also has a leading edge (an end on the downstream side in the transport direction, also referred to as an upper end) and a rear end (an end on the upstream side in the transport direction, also referred to as the lower end) of the paper S depending on the situation. It can be detected. Since the optical sensor 54 optically detects the edge of the paper S, the optical sensor 54 has higher detection accuracy than the mechanical paper detection sensor 53.

<About nozzle>
FIG. 5 is an explanatory diagram showing the arrangement of nozzles on the lower surface of the head 41.
On the lower surface of the head 41, a black ink nozzle group K, a cyan ink nozzle group C, a magenta ink nozzle group M, and a yellow ink nozzle group Y are formed. Each nozzle group includes a plurality of nozzles (180 in this embodiment) for ejecting ink of each color.

The plurality of nozzles of each nozzle group are aligned at a constant interval (nozzle pitch: k · D) along the transport direction. Here, D is the minimum dot pitch in the carrying direction (that is, the interval at the highest resolution of dots formed on the paper S). K is an integer of 1 or more. For example, when the nozzle pitch is 180 dpi (1/180 inch) and the dot pitch in the transport direction is 720 dpi (1/720 inch), k = 4.
The nozzles of each nozzle group are assigned a smaller number as the nozzles on the downstream side (# 1 to # 180). That is, the nozzle # 1 is located downstream of the nozzle # 180 in the transport direction. It should be noted that the optical sensor 54 described above is located at substantially the same position as the nozzle # 180 on the most upstream side with respect to the position in the paper transport direction.
Each nozzle is provided with an ink chamber (not shown) and a piezoelectric element. The ink chamber expands and contracts by driving the piezo element, and ink is ejected from the nozzle.

<Regarding Printer Driver 116>
FIG. 6 is a schematic explanatory diagram of basic processing performed by the printer driver 116. The components already described are given the same reference numerals, and the description thereof is omitted.

  In the computer 110, programs such as a video driver 112, an application program 114, and a printer driver 116 are operating under an operating system mounted on the computer 110. The video driver 112 has a function of displaying, for example, a user interface on the display device 120 in accordance with display commands from the application program 114 and the printer driver 116. The application program 114 has a function of performing image editing, for example, and creates data related to an image (image data). The user can give an instruction to print an image edited by the application program 114 via the user interface of the application program 114. Upon receiving a print instruction, the application program 114 outputs image data to the printer driver 116.

  The printer driver 116 receives image data from the application program 114, converts the image data into print data, and outputs the print data to the printer 1. Here, the print data is data in a format that can be interpreted by the printer 1, and is data having various command data and pixel data. Here, the command data is data for instructing the printer 1 to execute a specific operation. The pixel data is data relating to the pixels constituting the image to be printed.

  The printer driver 116 performs resolution conversion processing, color conversion processing, halftone processing, rasterization processing, and the like in order to convert image data output from the application program 114 into print data. Hereinafter, various processes performed by the printer driver 116 will be described.

  The resolution conversion process is a process of converting image data (text data, image data, etc.) output from the application program 114 into a resolution for printing on the paper S (hereinafter also referred to as print resolution). For example, when the print resolution is specified as 720 × 720 dpi, the image data received from the application program 114 is converted into image data having a resolution of 720 × 720 dpi. Note that the image data after the resolution conversion process is multi-gradation (for example, 256 gradations) RGB data represented by an RGB color space. Hereinafter, RGB data obtained by performing resolution conversion processing on image data is referred to as RGB image data.

  The color conversion process is a process for converting RGB data into CMYK data represented by a CMYK color space. The CMYK data is data corresponding to the ink color of the printer 1. This color conversion processing is performed by the printer driver 116 referring to a table (color conversion lookup table LUT) in which gradation values of RGB image data and gradation values of CMYK image data are associated with each other. Through this color conversion process, RGB data for each pixel is converted into CMYK data corresponding to the ink color. The data after the color conversion processing is CMYK data with 256 gradations represented by the CMYK color space. Hereinafter, CMYK data obtained by performing color conversion processing on RGB image data is referred to as CMYK image data.

  The halftone process is a process of converting high gradation number data into gradation number data that can be formed by the printer 1. For example, data representing 256 gradations is converted into 1-bit data representing 2 gradations or 2-bit data representing 4 gradations by halftone processing. In the halftone process, pixel data is created using the dither method, γ correction, error diffusion method, and the like so that the printer 1 can form dots dispersedly. When performing halftone processing, the printer driver 116 refers to a dither table when performing a dither method, refers to a gamma table when performing γ correction, and refers to a diffused error when performing an error diffusion method. Refer to the error memory for storage. The data subjected to the halftone process has a resolution (for example, 720 × 720 dpi) equivalent to the RGB data described above. The halftoned data is composed of 1-bit or 2-bit data for each pixel, for example. Hereinafter, of the halftone processed data, 1-bit data is referred to as binary data, and 2-bit data is referred to as multi-value data.

  The rasterizing process is a process of changing matrix image data in the order of data to be transferred to the printer 1. The rasterized data is output to the printer 1 as pixel data included in the print data.

<Settings of Printer Driver 116>
FIG. 7 is an explanatory diagram of a user interface of the printer driver 116. The user interface of the printer driver 116 is displayed on the display device via the video driver 112. The user can make various settings of the printer driver 116 using the input device 130.

  The user can select a print mode from this screen. For example, the user can select a high-speed print mode or a fine print mode as the print mode. Then, the printer driver 116 converts the image data into print data so as to have a format corresponding to the selected print mode. This print mode is associated with a print resolution (interval between dots when printing), and the print resolution is set to, for example, 720 dpi or 360 dpi by selecting the print mode. The printer driver 116 performs resolution conversion processing based on the print resolution, and converts the image data into print data.

  Further, the user can select the paper S used for printing from this screen. For example, the user can select plain paper or glossy paper as the paper S. If the type (paper type) of the paper S is different, the ink bleeding method and the drying method are also different, so that the ink amount suitable for printing is also different. Therefore, the printer driver 116 converts the image data into print data according to the selected paper type.

  As described above, the printer driver 116 converts image data into print data in accordance with conditions set via the user interface. The user can make various settings of the printer driver 116 on this screen, and can also know the remaining amount of ink in the cartridge.

<About printing operation>
FIG. 8 is a flowchart of processing during printing. Each process described below is executed by the printer-side controller 60 controlling each unit in accordance with a program stored in the memory 63. This program has a code for executing each process.

  Print command reception (S001): First, the printer-side controller 60 receives a print command from the computer 110 via the interface unit 61. This print command is included in the header of print data transmitted from the computer 110. Then, the printer-side controller 60 analyzes the contents of various commands included in the received print data, and performs the following paper feed processing / conveyance processing / dot formation processing using each unit.

  Paper Feed Process (S002): The paper feed process is a process for supplying the paper S to be printed into the printer 1 and positioning the paper S at a print start position (also referred to as a cue position). The printer-side controller 60 rotates the paper feed roller 21 and sends the paper S to be printed to the transport roller 23. Subsequently, the printer-side controller 60 rotates the transport roller 23 to position the paper S sent from the paper feed roller 21 at the print start position. When the paper S is positioned at the print start position, at least some of the nozzles of the head 41 are opposed to the paper S.

  Dot Formation Process (S003): The dot formation process is a process for forming dots on the paper S by intermittently ejecting ink from the head 41 that moves along the carriage movement direction. The printer-side controller 60 drives the carriage motor 32 to move the carriage 31 in the carriage movement direction. The printer-side controller 60 ejects ink from the head 41 based on the print data while the carriage 31 is moving. When the ink ejected from the head 41 lands on the paper S, dots are formed on the paper S. Since ink is intermittently ejected from the moving head 41, a dot row (raster line) composed of a plurality of dots along the carriage movement direction is formed on the paper S.

  Transport Process (S004): The transport process is a process of moving the paper S relative to the head 41 along the transport direction. The printer-side controller 60 drives the carry motor 22 and rotates the carry roller 23 to carry the paper S in the carrying direction. By this carrying process, the head 41 can form dots at positions different from the positions of the dots formed by the previous dot formation process.

  Paper discharge determination (S005): The printer-side controller 60 determines whether or not to discharge the paper S being printed. If data to be printed remains on the paper S being printed, no paper is discharged. Then, the printer-side controller 60 alternately repeats the dot formation process and the conveyance process until there is no more data to be printed, and gradually prints an image composed of dots on the paper S.

  Paper Discharge Process (S006): When there is no more data to be printed on the paper S being printed, the printer-side controller 60 discharges the paper S by rotating the paper discharge roller 25. The determination of whether or not to discharge paper may be based on a paper discharge command included in the print data.

  Determination of printing end (S007): Next, the printer-side controller 60 determines whether or not to continue printing. If printing is to be performed on the next paper S, the printing is continued and the paper feeding process for the next paper S is started. If printing is not performed on the next paper S, the printing operation is terminated.

=== Configuration of Platen 24 ===
There is a printing method called “borderless printing”. This printing method is a printing method in which an image is formed without creating a blank on the entire paper S. When performing “marginless printing”, the printer 1 ejects ink over a wider area than the paper S, applies the ink to the entire paper S, and forms an image on the entire paper S.

  In the case of “marginless printing”, since ink is ejected to a wider area than the paper S, there is ink that does not land on the paper S but land on the platen 24. However, if the ink that has landed on the platen 24 adheres to the back side of the paper S, the paper S becomes undesirably dirty. Therefore, in order to prevent the back side of the paper S from being stained, the platen 24 is provided with a protrusion (supporting portion) so that the paper S does not come into contact with the portion where the ink is adhered.

  FIG. 9A is a perspective view of components around the platen 24. FIG. 9B is a perspective view of the paper S conveyed by the conveyance roller 23. 10A and 10B are views of the state in which the paper S is transported as viewed from the side (carriage movement direction). In the figure, the components already described are denoted by the same reference numerals, and the description thereof is omitted.

  The platen 24 includes a plurality of protrusions 242. A plurality of the protrusions 242 are arranged along the carriage movement direction. Thereby, each protrusion 242 is arranged at a different position in the carriage movement direction. A plurality of protrusions 242 arranged in the carriage movement direction constitute a protrusion group.

  A plurality of protrusion groups (a plurality of protrusions 242 arranged in the carriage movement direction) are arranged along the transport direction. As a result, a groove along the carriage movement direction is formed between the protrusion group. The position of the protrusion 242 in the carriage movement direction is substantially the same for any protrusion group. Therefore, a groove along the transport direction is formed between the protrusion 242 and the protrusion 242.

  Ink that has not landed on the paper S during borderless printing is landed on the groove. Since the printer 1 performs borderless printing on paper S of various sizes (for example, postcards, B5 paper, A4 paper, etc.), the printer 1 corresponds to the position of the side edge of the paper S of each size along the transport direction. A plurality of groove portions are provided. Further, since it is necessary to perform borderless printing on the upper and lower ends of the paper S, at least two grooves along the carriage movement direction are formed. Conversely, a plurality of protrusions 242 are formed so as to form such grooves.

The paper S conveyed by the conveyance roller 23 is conveyed from the upper side to the lower side with respect to the platen 24 (FIG. 10A). The leading edge of the paper S conveyed obliquely contacts the protrusion 242 of the platen 24. When the leading edge of the paper S that contacts the protrusion 242 contacts the protrusion 242 disposed along the carriage movement direction, the leading edge of the paper S becomes wavy when viewed from the transport direction. When the transport roller 23 continues to transport the paper S, the paper S supported by the protrusions 242 of the platen 24 undulates (undulates) along the carriage movement direction and becomes bellows (accordion). However, the paper S has a shape that does not undulate in the transport direction. That is, the crest portion of the paper S that hits the wave is along the transport direction, and the valley portion is also along the transport direction. The crests and troughs of the paper S appear alternately in the carriage movement direction.
And since the paper S becomes such a shape and is conveyed in a conveyance direction, the paper S is conveyed without warping. As a result, in the middle of transporting the paper S, the leading edge of the paper S enters the groove formed along the carriage movement direction, and the paper S is clogged, or the leading edge of the paper S is lifted from the platen 24 and rubs the head 41. Can be prevented.

  However, when the paper S is deformed in a bellows like this, the landing position of the ink on the paper S is partially deviated from the target position, and the image quality of the printed image is partially deteriorated. There is a fear. FIG. 11 shows the paper S after printing in a plan view. The deteriorated portion of the image quality occurs in a valley portion of the paper S and has a strip shape along the transport direction.

 The reason why the landing position of the valley portion deviates is that the gap dimension G between the valley portion of the paper S and the nozzle of the head 41 deviates from the design value Gs. This will be described in detail with reference to FIGS. 12 to 14B. FIGS. 12 to 14B are explanatory diagrams of changes in the ink landing position depending on the gap dimension G, and are views of the state of the paper S being transported as viewed from the transport direction. As described above, since the paper S shown in FIG. 12 has a bellows shape on the platen 24, the gap dimension G between the nozzle and the paper S differs depending on the position in the carriage movement direction.

 On the other hand, as shown in FIG. 13, the carriage 31 ejects ink from the nozzles at the ejection speed Vi while moving in the carriage movement direction at the speed Vc. Therefore, the ejected ink is Vc in the carriage movement direction and the vertical direction, respectively. And fly with a velocity component of Vi and land on the paper S. Therefore, when the gap dimension G is large, the distance over which the ink flies increases, so the time until landing is long, and the landing position is shifted to the downstream side in the carriage movement direction as compared with the case where the gap dimension G is small. It will be.

 Here, from the viewpoint of the design of the platen 24, generally, as shown in FIG. 14A, the platen 24 has a gap size G with the nozzle at the peak portion of the paper S supported by the protrusions 242. It is designed to have a value Gs. Therefore, as shown in the figure, the ink ejected toward the mountain portion lands on the target position. However, as shown in FIG. 14B, in the valley portion, the gap size G is larger than the design value Gs, so that the ink lands on the downstream side in the carriage movement direction from the target position, and as a result. Thus, the image quality of the valley portion deteriorates.

  Therefore, in this embodiment, in order to improve the image quality of the valley portion of the paper S, the ink ejection timing is advanced for the valley portion based on the deviation ΔG of the gap dimension G from the design value Gs. The direction has changed. As a result, the valley portion is also landed substantially at the target position, thereby improving the image quality of the valley portion.

=== Printing Method of the Present Embodiment ===
Hereinafter, the ink ejection timing changing process according to the present embodiment will be described in detail.

<Basic concept of discharge timing change processing>
As described above, for the peak portion of the paper S, the ink reaches the target position, but for the valley portion, the deviation amount Δp based on the deviation ΔG of the gap dimension G from the design value Gs is more than the target position. Also land on the downstream side in the carriage movement direction (see FIG. 14B). Accordingly, when ink is ejected with the valley portion as the target position, it is only necessary to advance the ejection timing by the shift amount Δp. In this embodiment, this ejection timing change process is performed by the printer driver. 116 is performed in the process of converting RGB image data into print data. That is, FIG. 15 is an explanatory diagram of processing performed by the printer driver 116 according to the present embodiment, and an ejection timing changing process is added between the color conversion process and the halftone process, so that the color conversion is performed. A discharge timing changing process is performed on the processed CMYK image data.

  FIG. 16 shows an array diagram of pixel data in the CMYK image data at the end of the color conversion process. Here, the CMYK image data is composed of image data for each of C, M, Y, and K colors, and the image data for each color has the same data arrangement as that in FIG. Each grid of the grid in FIG. 16 represents one pixel data, and the pixel size of each pixel data is basically determined in the resolution conversion process based on the print mode, and may be 360 dpi or 720 dpi.

Here, the arrangement of the pixel data in the image data directly represents the positions of the pixels when ink is ejected onto the paper S. For example, the first pixel data row of the image data is data for forming the first raster line on the paper S, and the subsequent pixel data rows are sequentially assigned to the raster lines of the first row. It corresponds to data. Each pixel data in the pixel data row corresponds to data of each dot arranged in the carriage movement direction so as to form a raster line.
Accordingly, if the pixel data corresponding to the valley portion on this image data is re-recorded by shifting the landing position from the target position by a deviation amount Δp in the direction in which the discharge timing is advanced, the pixel data is discharged toward the valley portion. It is possible to make the ink to be landed substantially at the target position.

Here, the direction in which the ejection timing is advanced is a direction opposite to the direction in which the carriage 31 moves when ink is ejected based on the pixel data row.
For example, in the case of unidirectional printing in which ink is ejected only in the forward direction of the carriage movement direction, the backward direction is the direction in which the ejection timing is advanced over all raster lines. Therefore, when the shift amount Δp is equivalent to, for example, one pixel, a group of pixel data corresponding to the valley portion on the image data in FIG. 17A is divided by one pixel in the backward direction as shown in FIG. 17B. If the data is overwritten by being shifted by a certain amount, the ink ejection timing with respect to the valley portion is advanced.

 On the other hand, in the case of bidirectional printing in which ink is ejected in both the forward path and the backward path in the carriage movement direction, the carriage movement direction when ink is ejected for each raster line changes alternately. When shifting the pixel data of the valley portion on the image data of 18A, as shown in FIG. 18B, if the direction of shifting is alternately changed for each pixel data row, the ink ejection timing to the valley portion is advanced. It will be.

 If the process for shifting the pixel data in the valley portion is performed for all the C, M, Y, and K image data, the ejection timing changing process for the CMYK image data is completed. After that, if the printer driver 116 converts the CMYK image data into print data by performing the remaining halftone processing and rasterization processing of FIG. 15 as usual, and transmits the print data to the printer 1, The printer 1 can print a print image while improving the image quality of the valley portion. That is, since the discharge timing of the ink discharged toward the valley portion is advanced by the shift amount ΔP by the above-described change processing of the discharge timing, the ink is also landed substantially at the target position in the valley portion, Accordingly, the image quality of the valley portion is improved.

<About the valley part>
In the present embodiment, as shown in FIG. 19, the definition of the valley portion is centered on the portion CL of the paper S where the deviation ΔG from the design value Gs of the gap dimension G is the maximum, and a predetermined width on the left and right sides from there. This is a range extending over ΔW, which is equivalent to a range extending from an intermediate position MP between the projections 242 and 242 of the platen 24 to a predetermined width ΔW on the left and right. On the other hand, the protrusion arrangement of the platen 24 is fixed for each model of the printer 1 and is not changed. For this reason, the pixel data corresponding to the valley portion is also determined for each model of the printer 1, and therefore the address information on the arrangement of the pixel data corresponding to the valley portion is stored in the memory 63 of the printer 1 in advance. By doing so, the printer driver 116 can recognize the pixel data to be shifted.

  However, when there are a plurality of print modes, it is desirable to store the address information in association with the print mode. This is because the resolution of the image data changes according to the print mode, and the correspondence between the valley portion and the pixel data changes accordingly.

 The size of the predetermined width ΔW is set to, for example, the size of 1/4 or 1/8 of the interval L1 between the protrusions 242 and 242. However, the size is not limited to this, and is appropriately optimized. You can set it to the size you think. This optimum size is determined by an experimental method, for example, by printing a plurality of print images while shaking the size of the predetermined width ΔW as a parameter, and when these print images are viewed macroscopically, It can be decided by selecting the one with good image quality.

<About the number of pixel data shifts>
The shift number of the pixel data corresponding to the valley portion, that is, how many pixels the position of the pixel data is shifted is determined as follows.

First, the printer driver 116 obtains a deviation amount of the landing position from the target position assumed in the intermediate position MP (hereinafter referred to as an assumed deviation amount Δp) based on the following equation (1).
Δp = (ΔG / Vi) × Vc (1)
Here, as shown in FIG. 19, ΔG (mm) is a deviation ΔG from the design value Gs of the gap dimension G at the intermediate position MP, Vi is an ink ejection speed (m / s), and Vc is a carriage. The moving speed (m / s).

  These ΔG, Vi, and Vc are stored in advance in the memory 63 of the printer 1, and in particular, Vi and Vc that can change depending on the print mode are stored in association with the print mode as shown in FIG. ing. Then, every time RGB image data is transmitted from the application program 114, the printer driver 116 refers to the numerical values of ΔG, Vi, and Vc, for example, using the print mode as a key, and substitutes it into the equation (1). An assumed deviation amount Δp is obtained.

  However, in the image data, the pixel data can be shifted only in pixel units (for example, in the case of 35 microns when the resolution is 720 dpi). Therefore, strictly speaking, it is not possible to shift by the estimated deviation amount Δp of the calculation result. Is possible. For this reason, the printer driver 116 performs determination processing for determining the number of pixels to be shifted (the number of shifts) based on the calculation result of the assumed shift amount Δp.

FIG. 21 shows an example of this determination processing flow. Basically, a plurality of determination threshold values are prepared, and the size relationship between these determination threshold values and the calculation result of the assumed deviation amount Δp is compared to determine the number of pixels to be shifted. It is determined. In the illustrated example, two determination thresholds of 70 microns (corresponding to the size of two pixels when the resolution is 720 dpi) and 35 microns (corresponding to the size of one pixel when the resolution is 720 dpi) are prepared. .
Then, in step S20 in the flowchart of FIG. 20, it is determined whether or not the calculation result of the assumed deviation amount Δp exceeds 70 microns. To do. On the other hand, if it does not exceed, the process proceeds to step 40, where it is determined whether or not the calculation result of the estimated deviation amount Δp exceeds 35 microns. One pixel is determined. On the other hand, if not exceeded, the process proceeds to step S60, where the number of pixels to be shifted is determined as 0 pixel, and in this case, the pixel data is not shifted.

Since the deviation ΔG can vary depending on the type of the paper S as the medium, the memory 63 preferably stores the deviation ΔG for each type of the paper S as shown in FIG.
In addition, when the interval L1 between the protrusions 242 and 242 changes according to the position in the carriage movement direction, the deviation ΔG may be different for each intermediate position MP between the protrusions 242 and 242. Therefore, as shown in FIG. 23, it is desirable to store the deviation ΔG in association with each intermediate position MP in the carriage movement direction.

<Determination of Deviation ΔG from Design Value Gs of Gap Dimension G at Intermediate Position MP>
The deviation ΔG is stored in the memory 63 before shipment of the printer 1, and the deviation ΔG is obtained by the following method. As the simplest example, there is a method in which the paper S is supported on the platen 24 and the difference between the peak portion and the valley portion of the paper S is actually measured to obtain the printer 1 as shown below. The correction pattern may be printed and indirectly obtained from the correction pattern.

FIG. 24 shows a state in which the correction pattern is printed in a plan view of the paper S. First, while moving the carriage 31, ink is ejected from the intermediate position MP as a target position in the forward path, and in the forward path. Ink landing marks are formed. Also, ink is ejected with the intermediate position MP as a target position in the return path, and ink landing marks are formed in the return path. Note that these landing traces are the correction patterns, but each landing trace has a dot array in which dots are aligned in the transport direction in order to eject ink from all nozzles of the nozzle group.
Here, when the gap dimension G between the nozzle and the paper S coincides with the design value Gs at the intermediate position MP, both the forward and return landing marks are formed at the intermediate position MP of the target position. That is, these landing marks are formed on the intermediate position MP.

However, when the positions of the landing marks are shifted, the half value of the shift amount ΔX is the landing position error Δp1 caused by the deviation ΔG from the design value Gs of the gap dimension G. . Here, the relationship of the above-described equation (1) is established between the deviation ΔG and Vi, Vc, and Δp1. Therefore, the equation (1) can be transformed into the following equation (2), and the deviation ΔG can be obtained by substituting each value into Δp1, Vi, Vc of the equation (2).
ΔG = (Δp1 × Vi) / Vc (2)

=== Other Embodiments ===
The above-described embodiment is mainly described for a printer. Among them, a printing apparatus, a recording apparatus, a liquid ejection apparatus, a printing method, a recording method, a liquid ejection method, a printing system, a recording system, and a computer system are included. Needless to say, the disclosure includes a program, a storage medium storing the program, a display screen, a screen display method, a printed material manufacturing method, and the like.

  Moreover, although the printer etc. as one embodiment were demonstrated, said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

  In the above-described embodiment, as illustrated in FIG. 15, the ejection timing changing process is performed on the CMYK image data after the color conversion process. However, the present invention is not limited to this, and the halftone process or the rasterization process is not limited thereto. You may make it perform with respect to subsequent image data.

  In the above-described embodiment, the pixel data in the image data is shifted in units of pixels to change the ejection timing. However, the present invention is not limited to this. For example, when the drive signal for driving the piezo element based on the pixel data has a plurality of pulses for the period of one pixel as shown in the upper part of FIG. 25, the ink is ejected by selecting the pulse. The timing may be changed. In the illustrated example, the drive signal has three pulses in a period of one pixel. When ink is ejected toward pixels other than the valley portion of the paper S, the middle pulse is selected to drive the piezo element as shown in the middle of the figure. On the other hand, when ink is ejected toward the valley pixels, the left pulse is selected to drive the piezo element as shown in the lower part of FIG.

  In the above-described embodiment, ink is ejected using a piezo element. However, the method for discharging the liquid is not limited to this. For example, other methods such as a method of generating bubbles in the nozzle by heat may be used.

It is explanatory drawing of the whole structure of a printing system. 1 is a block diagram of an overall configuration of a printer 1. FIG. 1 is a schematic diagram of an overall configuration of a printer 1. FIG. 2 is a cross-sectional view of the overall configuration of the printer 1. FIG. It is explanatory drawing which shows the arrangement | sequence of a nozzle. 6 is an explanatory diagram of processing performed by a printer driver. FIG. 3 is an explanatory diagram of a user interface of a printer driver. FIG. It is a flowchart of the process at the time of printing. FIG. 11A is a perspective view of components around the platen 24, and FIG. 11B is a perspective view of the paper S conveyed by the conveyance roller 23. 10A and 10B are views of the state in which the paper S is transported as viewed from the side (carriage movement direction). It is a top view of the paper S after printing for demonstrating the deterioration part of an image quality. FIG. 5 is an explanatory diagram of a change in ink landing position depending on a gap dimension G. FIG. 5 is an explanatory diagram of a change in ink landing position depending on a gap dimension G. 14A and 14B are explanatory diagrams of changes in the ink landing position due to the gap size G. FIG. It is explanatory drawing of the process which the printer driver 116 of this embodiment performs. FIG. 6 is an array diagram of pixel data in CMYK image data at the end of color conversion processing. FIG. 17A is a diagram illustrating an arrangement of pixel data of image data related to unidirectional printing. FIG. 17A shows a state before a discharge timing change process, and FIG. 17B shows a state after a discharge timing change process. FIGS. 18A and 18B show an arrangement of pixel data of image data related to bidirectional printing, FIG. 18A shows a state before the discharge timing change process, and FIG. 18B shows a state after the discharge timing change process. It is explanatory drawing about the part of a trough. 4 is a diagram illustrating a state in which Vi and Vc are stored in a memory 36 in association with a print mode. FIG. It is a determination processing flowchart for determining the number of pixels to be shifted. It is a figure which shows a mode that deviation (DELTA) G is memorize | stored in the memory 36 matched with the kind of paper. It is a figure which shows a mode that deviation (DELTA) G is memorize | stored in the memory 36 matched with the intermediate position MP. It is a top view of the paper S which shows a mode that the pattern for correction | amendment is printed. It is a figure for demonstrating other embodiment which concerns on this invention.

Explanation of symbols

1 printer,
20 transport unit, 21 paper feed roller, 22 transport motor (PF motor),
23 transport roller, 24 platen, 25 discharge roller,
30 Carriage unit, 31 Carriage,
32 Carriage motor (CR motor),
40 head units, 41 heads,
50 detector groups, 51 linear encoder, 52 rotary encoder,
53 Paper detection sensor, 54 Optical sensor,
60 printer-side controller, 61 interface unit, 62 CPU,
63 memory, 64 unit control circuit 100 printing system, 110 computer,
112 video drivers, 114 application programs,
116 printer driver, 120 display device,
130 input device, 130A keyboard, 130B mouse,
140 recording / reproducing apparatus,
140A flexible disk drive device,
140B CD-ROM drive device,
161 Interface unit, 162 CPU, 163 Memory

Claims (15)

(A) a nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
(B) a memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
(C) a controller that determines a liquid discharge timing for the predetermined position based on the information, and sets a liquid discharge timing as a predetermined timing for at least some positions other than the predetermined position;
A liquid ejection system comprising (D). The liquid ejection system according to claim 1, wherein
A position at which the ejection timing is determined based on the information extends over a predetermined range including the predetermined position. The liquid ejection system according to claim 1 or 2,
A plurality of support portions are provided along the moving direction to support the medium, and a gap dimension between the support portion and the nozzle is the same across the plurality of support portions,
The liquid discharge system according to claim 1, wherein the predetermined position is an intermediate position between the support portions adjacent to each other. The liquid ejection system according to claim 3, wherein
The gap dimension between the portion of the medium contacting the support portion and the nozzle is a design value of the gap dimension,
The liquid ejection system according to claim 1, wherein the information is a deviation of the gap size at the predetermined position from the design value. The liquid ejection system according to claim 4, wherein
The controller ejects liquid based on image data input to the controller,
The controller is configured to advance the liquid ejection timing by an amount based on the information with respect to a position within a predetermined range including the intermediate position, rather than the timing at which the liquid is ejected based on the image data. Liquid ejection system. The liquid ejection system according to any one of claims 3 to 5,
The nozzle is movable in both directions of the moving direction,
The controller causes the liquid to be ejected from the nozzle with the intermediate position as a target position in both the bidirectional forward path and the backward path,
A liquid ejection system characterized in that the information is obtained based on deviations in the actual landing positions of liquid in the forward path and the backward path. The liquid ejection system according to any one of claims 3 to 6,
The medium is a flexible sheet;
When the sheet body is supported by the plurality of support portions, the sheet body is deformed such that a portion corresponding to the support portion has a mountain shape and a portion corresponding to the intermediate position has a valley shape. A liquid discharge system characterized by that. The liquid ejection system according to any one of claims 1 to 7,
The liquid ejection system according to claim 1, wherein the memory stores information related to the gap size for each type of the medium. The liquid ejection system according to any one of claims 1 to 8,
The liquid is ink;
The liquid ejection system is a printing system that forms an image on the medium. The liquid ejection system according to claim 9, wherein
The nozzle is movable in both directions with respect to the moving direction;
The liquid ejection system, wherein the nozzle ejects the liquid both in the bidirectional forward path and the backward path. (A) a nozzle that discharges liquid toward the medium while moving in a predetermined movement direction;
(B) a memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
(C) a controller that determines a liquid discharge timing for the predetermined position based on the information, and sets a liquid discharge timing as a predetermined timing for at least some positions other than the predetermined position;
A liquid ejection system comprising (D),
The position for determining the ejection timing based on the information is over a predetermined range including the predetermined position,
A plurality of support portions are provided along the moving direction to support the medium, and a gap dimension between the support portions and the nozzles is the same across the plurality of support portions, and the predetermined position Is an intermediate position between the support portions adjacent to each other,
The gap dimension between the portion of the medium contacting the support and the nozzle is a design value of the gap dimension, and the information is a deviation from the design value of the gap dimension at the predetermined position,
The controller discharges liquid based on image data input to the controller, and the controller sets the liquid discharge timing to the image data for a position within a predetermined range including the intermediate position. Earlier than the timing of ejection based on the information,
The nozzle is movable in both directions of the movement direction, and the controller discharges liquid from the nozzle with the intermediate position as a target position in both of the bidirectional forward path and the return path, respectively. Obtain the information based on the deviation of the actual landing position of the liquid in the forward and return paths,
The medium is a flexible sheet body, and when the sheet body is supported by the plurality of support portions, a portion corresponding to the support portion of the sheet body has a mountain shape and is located at the intermediate position. The corresponding part is deformed to form a valley,
The memory stores information on the gap size for each type of the medium,
The liquid is ink, and the liquid ejection system is a printing system that forms an image on the medium;
The liquid ejection system, wherein the nozzle ejects the liquid both in the bidirectional forward path and the backward path. A nozzle that discharges liquid toward the medium while moving in a predetermined moving direction;
A memory for storing information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction;
A controller for determining a liquid discharge timing for the predetermined position based on the information, and a liquid discharge timing for at least some positions other than the predetermined position as a predetermined timing;
A liquid ejection apparatus comprising: A liquid discharge method for discharging liquid from the nozzle toward the medium while moving the nozzle in a predetermined movement direction,
For the predetermined position in the movement direction, the liquid ejection timing is determined based on information on the gap size between the nozzle and the medium,
A liquid ejection method, wherein the liquid ejection timing is set to a predetermined timing for at least some positions other than the predetermined position. A nozzle that discharges liquid toward the medium while moving in a predetermined moving direction;
A program that is executed in a liquid ejection system including a memory that stores information on a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the moving direction,
The liquid ejection timing is determined based on the information for the predetermined position, and the liquid ejection timing is set as the predetermined timing for at least some positions other than the predetermined position. Program to do. A nozzle that discharges liquid toward the medium while moving in a predetermined moving direction;
In a liquid ejection control apparatus for controlling a liquid ejection system provided with a memory that stores information related to a gap dimension between the nozzle and the medium in correspondence with a predetermined position in the movement direction,
The liquid ejection timing is determined based on the information for the predetermined position, and the liquid ejection timing is set as the predetermined timing for at least some positions other than the predetermined position. Control device.