JP3880253B2 - Recording method and recording apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording method and a recording apparatus for recording an image on a recording medium, for example, a recording apparatus such as a color printer.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, recording apparatuses that record ink on recording paper or fabric by ejecting ink from nozzles as recording elements of a recording head are known, and image quality and recording speed are improved by various methods. Yes.
[0003]
As one of such methods, the recording speed is improved by performing reciprocal recording with a two-stage recording head spaced apart in the transport direction, and the image quality is improved by performing sequential multi-scan (SMS). A technique for improving the capacity has been proposed (Japanese Patent Laid-Open No. 9-70990).
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional technology, one line of pixels is formed by scanning two stages of recording heads arranged apart in the transport direction once each (hereinafter referred to as two-pass recording). Therefore, as shown in FIG. 22, the half band 1 recorded by the forward scan of the first head and the forward scan of the second head, and the half band recorded by the forward scan of the first head and the backward scan of the second head. 4, half band 3 recorded by the backward scan of the first head and the backward scan of the second head, and half band 4 recorded by the backward scan of the first head and the forward scan of the second head. A band (half the head size) is present on the recording paper.
[0005]
Then, recording is repeated in a total of two band periods with these four types of half bands as a set.
[0006]
In general, there are differences in the landing state (landing position, dot size, dot shape, etc.) of the forward and backward dots due to the satellite of the head, etc. Therefore, each of the above four types of half-bands has individuality in recording. Since the combination (4 types) of recording elements that record half bands in units of two bands is repeated, half-band unevenness occurs.
[0007]
Further, in order to improve image quality and recording speed, a plurality of (for example, two) the same recording heads are arranged in the movement direction of the carriage, and one line (band) is formed in cooperation with the plurality of recording heads. Can be considered.
[0008]
In FIG. 23, one line image is formed by two-pass printing in which two recording heads arranged continuously in the carriage movement direction are scanned once each by reciprocating scanning. Here, two types of one band (band 1 recorded by the forward scan of the first head and the forward scan of the second head, and band 2 recorded by the backward scan of the first head and the forward scan of the second head ( (Head size) exists on the recording paper. Then, printing is repeated in a total of two band periods, with these two types of one band as a set.
[0009]
In this case as well, as described above, the two types of bands each have individuality in recording due to the difference in the dot landing state between the forward and backward paths due to satellite dots of the recording head, and nozzles that record one band in units of two bands. By repeating this combination (two ways), one-band unevenness occurs.
[0010]
The present invention has been made in order to solve the above-described problems of the prior art, and an object of the present invention is to provide a recording method capable of recording at high speed and high image quality by suppressing half-band unevenness and band unevenness, and a recording apparatus using the same Is to provide.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a recording medium having a first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements for recording the same color as the first recording head. A recording method for performing reciprocal scanning to record on the recording medium in band units, Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Generating first data for recording and second data for recording by the second recording head, and using the mask pattern for the first data, third data for forward recording and fourth data for backward recording Dividing the second data into fifth data for forward recording and sixth data for backward recording according to a mask pattern; The first recording head In the forward direction Scan While based on the third data band Against A first recording step for performing recording, and the first recording head Return trip Scan in the direction While based on the fourth data band Against A second recording step for performing recording, and the second recording head In the forward direction Scan While based on the fifth data band Against A third recording step for performing recording, and the second recording head Said return Scan in the direction While based on the sixth data band Against A fourth recording step for performing recording, a conveying step for conveying the recording medium between the first and second recording steps, and between the third and fourth recording steps, In the band Multiple Raster Respectively In for , Four different recording elements are used in the first to fourth recording steps. Recorded It is characterized by that.
[0014]
The second recording head is located downstream of the first recording head in the transport direction of the recording medium.
[0015]
When the distance between the first recording head and the second recording head is D and the width of the band is H, the relationship D = (2n + 1) × H / 2 (n is an integer) Meet It is characterized by that.
[0016]
The second recording head is , For the first recording head Above In the scanning direction Spaced apart It is characterized by that.
[0017]
The recording element includes an ejection port for ejecting ink.
[0018]
According to another aspect of the present invention, a first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements that perform recording of the same color as the first recording head are arranged apart from each other in the scanning direction. A recording method in which a carriage is reciprocally scanned with respect to a recording medium to perform recording on the recording medium in band units, Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Generating first data for recording and second data for recording by the second recording head, and using the first mask pattern, the first data for the third data for forward recording and the second data for backward recording. Dividing the data into four data; dividing the second data into fifth data for forward recording and sixth data for backward recording with a second mask pattern different from the first mask pattern; Scan the carriage in the forward direction However, based on each of the third data and the fifth data The first and second recording heads Driving each one band Against A recording step, and scanning the carriage in the backward direction. However, based on each of the fourth data and the sixth data The first and second recording heads Driving each one band Against A recording step, and a transporting step of transporting the recording medium by a half band width between the scanning in the forward direction and the scanning in the backward direction, and for any raster in the band However, the recording element of the first recording head used during the forward scan, the recording element of the second recording head used during the forward scan, the recording element of the first recording head used during the backward scan, and the return path Recording is performed using four different recording elements that are combinations of recording elements of the second recording head used during scanning.
[0019]
In another aspect of the present invention, a reciprocating scan of a first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements for performing recording of the same color as the first recording head with respect to a recording medium. A recording apparatus that records on the recording medium in units of bands, and among the recording data and non-recording data constituting the image data corresponding to the band, the recording data is the first recording head and the first recording data. Means for generating first data for recording with the first recording head and second data for recording with the second recording head by alternately distributing to the two recording heads; Means for dividing the first data into third data for outward recording and fourth data for backward recording according to a mask pattern; and the second data is divided into fifth data for outward recording according to a mask pattern; Means for dividing into sixth data for return path recording; The first recording head In the forward direction Let me scan Based on the third data The band Against A first recording operation for recording, the first recording head Return trip Scan in the direction Based on the fourth data band Against A second recording operation for recording, the second recording head In the forward direction Let me scan Based on the fifth data band Against A third recording operation for recording, the second recording head Said return Scan in the direction Based on the sixth data band Against Means for performing a fourth recording operation for performing recording, and transport means for transporting the recording medium during the first and second recording operations and between the third and fourth recording operations; For each of a plurality of rasters constituting the band using four different recording elements in the first to fourth recording operations. But line Be called It is characterized by that.
[0023]
According to another aspect of the present invention, a first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements that perform recording of the same color as the first recording head are arranged apart from each other in the scanning direction. A recording apparatus that performs a reciprocating scan with respect to a recording medium to perform recording on the recording medium in a band unit, Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Means for generating second data for recording with the first data for recording and the second recording head, and the first data for the third data for forward recording and for the backward recording with a first mask pattern And means for dividing the second data into fifth data for forward recording and sixth data for backward recording by a second mask pattern different from the first mask pattern. Means, Scan the carriage in the forward direction While based on the third data and the fifth data respectively The first and second recording heads Driving each one band Against The recording operation, and scanning the carriage in the backward direction. However, based on each of the fourth data and the sixth data The first and second recording heads Driving each one band Against Means for performing an operation for performing recording, and conveying means for conveying the recording medium by a half band width between the scanning in the forward direction and the scanning in the backward direction. The first recording head recording element used during the forward scanning, the second recording head recording element used during the forward scanning, and the recording of the first recording head used during the backward scanning also for the second raster. Recording is performed using four different recording elements each consisting of a combination of elements and recording elements of the second recording head used during the backward scanning. But line Be called It is characterized by that.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
Exemplary embodiments of the present invention will be described in detail below with reference to the drawings. However, as long as there is no specific description about components, relative arrangement of program modules, numerical values such as resolution, etc. described in this embodiment, the scope of the present invention is limited only to them. It is not a thing.
[0039]
[First Embodiment]
The outline of the recording apparatus according to the first embodiment of the present invention will be described below in detail with reference to FIGS. The recording apparatus according to the present embodiment is a recording apparatus that performs reciprocal recording by arranging two recording heads side by side in the transport direction for the same ink color. In addition, after distributing data to two print heads for the same ink color by SMS processing, it is further divided into forward print data and return print data using a mask, so that ink discharged from four different nozzles can be used. One line is recorded (hereinafter referred to as four-pass recording). In particular, the recording apparatus is configured to be able to select and perform 2-pass recording and 4-pass recording.
[0040]
<Overall configuration of image forming device>
FIG. 4 is a block diagram showing a conceptual configuration of the recording apparatus according to the first embodiment of the present invention.
[0041]
In FIG. 4, reference numeral 1 denotes an external device such as a host computer, which exchanges image data and various data / commands with a recording device (hereinafter referred to as a printer) 2.
[0042]
The printer 2 performs interface control (hereinafter referred to as I / F unit) 4 for controlling communication of data and commands with the external device 1 and analyzes received data / commands to control the operation of the entire printer 2. Control unit 5 (mainly composed of CPU, program ROM, work area RAM, etc.) and display / operation unit 6 (interface such as LCD and key switch) as an interface to the operator of the printer 2 An image processing unit 11 that stores input image data and converts it into image data that matches the characteristics of the printer 2, a carriage unit 18 that includes a head and its drive unit, and a carriage A carriage motor 15 that is a drive source for moving the unit 18 and a carriage motor that controls the drive of the carriage motor 15 According to the movement of the moving unit 14, the conveyance motor 17 that is a drive source for moving the recording medium such as recording paper and cloth, the conveyance motor driving unit 16 that controls the conveyance motor 17, and the carriage unit 18. And an encoder unit 8 for generating a pulse and inputting the pulse to the image processing unit 11 in order to synchronize with the transfer of the image data. The I / F unit 4 and the control unit 5 are included in the CPU control unit 3.
[0043]
The carriage unit 18 is equipped with a front head unit 12 provided on the upstream side in the conveyance direction of the recording medium and a back head unit 13 provided on the downstream side. There are provided recording heads 22 and 23 for discharging ink for use, and head driving units 20 and 21 for driving the recording heads 22 and 23 in accordance with image signals. The recording heads provided in each head unit are generally provided in the number of colors desired to be output. For example, it may be four Y, M, C, Bk, or other special colors that are impossible or difficult to express with the three primary colors (metal colors such as gold and silver, vivid red and blue, etc.) In addition to four for the color ink, a total of eight may be used. Further, a larger number of recording heads may be provided. The recording apparatus to which the present invention can be applied is not limited to a color printer, and may be a monochrome printer and may have a single recording head.
[0044]
As an example, a recording apparatus provided with eight recording heads 22 and 23 will be described below.
[0045]
<Mechanical mechanism of recording device>
FIG. 6 is a diagram showing a mechanical configuration of the recording apparatus centering on the carriage unit 18. In this figure, 19 is a recording sheet as a recording medium, 200 is a transport unit that transports the recording sheet 19, 201 is a printer unit that performs recording, and 202 is a discharge unit that stocks the recorded recording sheet 19. is there. Of the transport unit 200, 203 is an unwinding roller around which the recording paper 19 is wound, 204 and 205 are pressing rollers, 206 is a driving roller, 207 and 208 are platen units that maintain the flatness of the recording unit, 209 is a pressing roller, 210. Is a driving roller, 211 is a cutting portion for cutting the recording paper 19, 212 is a pressing roller for the cutting portion, and 213 is a support rail for placing and supporting the carriage unit 18 on top. The drive rollers 206 and 210 use the conveyance motor 17 (FIG. 4) as a drive source and obtain the drive force via a transmission mechanism such as a belt (not shown). The carriage unit 18 moves horizontally on the support rail 213 by the carriage motor 15 (FIG. 4). The encoder unit 8 includes a linear encoder (not shown) and a detection circuit arranged horizontally in the moving direction of the carriage unit 18, and the drive unit of the carriage unit 18 and the linear encoder are connected to each other.
[0046]
After the recording paper 19 is unwound according to the rotation of the unwinding roller 206, the recording paper 19 is transported substantially horizontally by the transport unit 200 provided at a portion facing the printer unit 201 via the presser rollers 204 and 205. Then, it is cut into a predetermined length by the cutting unit 211 and discharged to the paper discharge unit 202.
[0047]
The recording paper 19 thus transported is applied with a printing agent by the printer unit 201 in the area between the platen units 207 and 208.
[0048]
The carriage unit 18 provided in the printer unit 201 is scanned in a direction different from the conveyance direction (sub-scanning direction) of the recording paper 19, for example, in the width direction of the recording paper 19 orthogonal to the conveyance direction.
[0049]
In the present embodiment, an inkjet head as a recording head, for example, Canon Inc., which has a heating element that generates thermal energy that causes film boiling in ink as energy used to eject ink, is proposed. A bubble jet head is used. Then, the recording paper transported substantially horizontally by the transport unit 100 is used in a state where the ink ejection port as the printing agent application element is directed downward, thereby eliminating the water head difference between the ejection ports and ejecting the recording paper. The conditions are made uniform to enable good image formation, and uniform recovery processing is possible for all the ejection openings.
[0050]
FIG. 7A is a diagram showing a relative arrangement of the recording units 19 and the head units 12 and 13 on the front side and the back side when viewed from the direction P in FIG. As shown in the figure, the transport direction in which the recording paper 19 is fed is the sub-scanning direction, and the scanning direction in which the carriage unit 18 is fed is the main scanning direction. The front head unit 12 is provided with recording heads F1 to F8, and the recording heads R1 to R8 of the back head unit 13 are provided.
[0051]
The distance between the recording heads F1 to F8 and the recording heads R1 to R8 is referred to as an inter-unit gap D. When the recording width (also referred to as a band width) of the recording head is H, between D and H,
D = (2n + 1) × H / 2 (n is an integer)
The relationship is established.
[0052]
Accordingly, as shown in FIG. 7B, when the recording paper 19 is conveyed by one band width with respect to the carriage unit 18, the recording heads R1 to R8 of the recording heads F1 to F8 are located in the middle of the recording joints. The recording joint is located (only one recording head is shown in the figure for easy understanding). As a result, various errors related to the conveyance of the recording paper, and streak lines (clearances and overwraps) caused by ink bleeding can be virtually unrecognized. The n may be an arbitrary integer, but in the following description, the unit gap D = 2.5 × H.
[0053]
The distance between the recording heads in the same head unit (distance in the main scanning direction) is called a head gap and is represented by d. The recording width in the main scanning direction is represented by W.
[0054]
As described above, the printer 2 is provided with two head units and performs recording by the SMS (sequential multi-scan) method. The SMS here is intended to reduce density unevenness due to the individuality of the nozzles, and to make the frequency of use of the two heads uniform, and to record data to be recorded (excluding blank portions). The recording density is finally obtained by dividing the recording heads F1 to F8 in the front head unit 12 and the recording heads R1 to R8 in the back head unit 13 and recording at half the recording density. In this case, an image is formed.
[0055]
Each head unit of the printer 2 performs reciprocal recording, and recording is performed in the reverse direction every time one band is recorded.
[0056]
<Recording device sequence>
On the premise of the above mechanical configuration, returning to FIG. 4, the operation of the recording apparatus will be described.
[0057]
First, when the printer 2 is turned on, the control unit 5 includes various hardware such as an internal RAM and an I / O unit, a display / operation unit 6, an I / F unit 4, and an image processing unit 11. Perform initial check and initialization, and perform the mechanistic. Specifically, by moving a carriage motor 15 or a recovery system unit (not shown) as a mechanistic, the carriage unit 18 is moved to a predetermined HP (home position), and the recovery system unit (the recording heads 22, 23) is moved. The mechanism around the recording head (for example, preventing clogging) is moved to forcibly eject ink and suck it. Next, the control unit 5 validates (enables) the interface with the host computer 1 for the I / F unit 4, and sends a message notifying the display / operation unit 6 that “READY” is ready. indicate. In this state, the control unit 5 is waiting for an input from the host computer 1 or an input from the display / operation unit 6 and is also monitoring whether various errors have occurred. If an error occurs in this state, error processing is performed.
[0058]
When the input from the host computer 1 is in the I / F unit 4, the control unit 5 determines whether the input command is a transfer command, a recording command, or another command, and processes such as setting and operation corresponding to the command. To do. The command input from the display / operation unit 6 is directly received by the control unit 5 and the same processing is performed.
[0059]
If it is an image transfer command, the control unit 5 confirms that input is possible, sets the image processing unit 11 to the input mode, and then stores image data and color arrangement information (referred to as a palette table) in the image processing unit 11. To do.
[0060]
If the command is a recording command, the control unit 5 confirms that the printer 2 is ready for recording, and then makes predetermined settings for each unit such as the image processing unit 11 to instruct the start of recording, and to record the input image. I do. The setting here includes setting of a parameter set in the image processing unit 11 such as a recording mode (2-pass recording mode or 4-pass recording mode or high-speed 4-pass mode), an image recording size (width and length), and the like. .
[0061]
Specifically, the control unit 5 records one scan with a bandwidth H while moving the carriage unit 18 in the main transport direction by rotating the carriage motor 15 in the forward direction via the carriage motor drive unit 14. I do. Further, the recording motor 19 is conveyed by the bandwidth H by driving the conveyance motor 17 by the conveyance motor driving unit 16. This is called a one-band recording operation. During this time, the image data for one band read from the image memory unit in the image processing unit is converted in the image processing unit 11 and sent to the head driving units 20 and 21. The head driving units 20 and 21 drive the recording heads 22 and 23 according to the sent image data to discharge ink, thereby forming an image on the recording paper 19.
[0062]
Each time recording of one band is completed, the control unit 5 determines whether or not all of the image data instructed to be recorded has been recorded. If all of the image data has been completed, the control unit 5 returns to waiting for input. Record.
[0063]
If it is another command, the control part 5 will perform various processes according to the command. For example, there are change commands for changing various recording modes, and modes such as an image quality emphasis mode (4-pass printing), a printing speed emphasis mode (2-pass printing), and an ink saving mode can be selected.
[0064]
<Configuration of Image Processing Unit 11>
Next, processing in the image processing unit 11 of the printer 2 when a recording command is input will be described.
[0065]
FIG. 5 is a block diagram illustrating the internal configuration of the image processing unit 11 and its processing. In FIG. 5, 30 is an image memory unit for storing and reading image data. A multi-value / binary conversion unit 31 binarizes the image data PLT from the image memory unit 30 and outputs binary image data C1 to C8 for each color. 32 distributes the binary image data C1 to C8 to the front head unit 12 and the back head unit 13, respectively (this is referred to as SMS processing), and the front recording image data FL1 to FL8 and the back recording image data. It is an SMS processing unit that outputs RL1 to RL8. A registration adjusting unit 33 outputs the image data FC1 to FC8 for front recording and the image data RC1 to RC8 for back recording, which temporarily store the SMS processed image data and read out at a predetermined timing. 34, when the registration-adjusted data FC1 to FC8 and RC1 to RC8 are recorded in four passes, the image data for forward recording of each recording head FFW1 to FFW8, RFW1 to RFW8, and for the backward recording of each recording head The output control unit can convert image data FBW1 to FBW8 and RBW1 to RBW8. When performing two-pass printing, the output control unit 34 converts the registration-adjusted data FC1 to FC8 and RC1 to RC8 into print head data FH1 to FH8 and RH1 to RH8.
[0066]
More specifically, the image memory unit 30 is configured to store image data PLT with 8 bits per pixel, and stores image data of a basic size. Further, it has a function of repeatedly reading the same data in the main scanning direction and the sub-scanning direction and a function of enlarging when reading. The image data PLT is data obtained by encoding an ink color scheme. The readout direction is sequentially read out for each pixel in the main scanning direction with the upper left of the image as the origin.
[0067]
The multi-value / binary conversion unit 31 is a palette conversion unit, an output gamma conversion unit, and a head density correction unit (hereinafter referred to as an HS unit) that convert the input data PLT that is code data into ink color data C1 to C8. It has a binary conversion unit, and image data is also processed in that order. Based on the color arrangement information (palette table) stored in the LUT (lookup table) of the palette conversion unit, the code data PLT is converted into ink color data C1 to C8.
[0068]
The registration adjustment unit 33 performs a read / write operation to the connection memory (comprising a SIM module) that compensates for the inter-unit gap D between the front head unit 12 and the back head unit 13. It has a memory control part to control. Reads / writes to the connecting memory section are independently addressed and can be accessed simultaneously. In addition, the registration adjustment is performed by adjusting the read timing in the memory control unit. Further, the writing to the connecting memory unit is sequentially performed in the raster direction with the upper left end as the origin, and the reading is sequentially read in the nozzle arrangement direction of the recording head (the direction opposite to the recording paper conveyance direction). The lead origin is the upper left corner on the forward path (FW) and the upper right corner on the return path (BW) in order to support reciprocal recording.
[0069]
<SMS processing>
Next, the image data distribution method performed by the SMS processing unit 32 and the output control unit 34 in FIG. 5 will be described in detail with reference to FIG.
[0070]
FIG. 1A is a diagram illustrating a method for distributing image data stored in the image memory 30 to each head. The following description will be given focusing on the image data C1 of one color and the recording heads F1 and R1 corresponding to the image data C1, but the same processing can be performed for other colors.
[0071]
This drawing shows the distribution of image data of an 8 pixel × 8 pixel region for the sake of simplicity.
[0072]
When distributing the image data, the recording dots are distributed so as to perform multi-pass recording. Multi-pass printing is an area formed by a single main scan using all the printing elements of a printing head having a plurality of printing elements, that is, a predetermined area within one band, for example, one line is printed by a plurality of scans. That means. For example, when one line in the main scanning direction is recorded by a plurality of nozzles using an ink jet head, the individuality of the nozzles is less likely to occur than when one line is recorded by one nozzle. That is, the variation in the density of each line is prevented from occurring due to the variation in the size of the ink droplet ejected by each nozzle and the variation in the ink ejection direction. Since one line is formed by a plurality of nozzles, the randomness of the nozzle characteristics of each inkjet head is used to reduce density unevenness. There are various types of multi-pass printing depending on the number of passes (nozzles for printing one line). In the image processing unit 11, the SMS processing unit 32 distributes the heads F1 and R1 in two. Since the image data FC1 and RC1 can be further divided into two data, the forward recording data and the backward recording data, in the output control unit 34, as a result, 4-pass recording is possible.
[0073]
A method for distributing image data in the SMS processing unit 32 will be described.
[0074]
In FIG. 1A, the SMS processing unit 32 uses the binary data C1 from the multi-value / binary conversion unit 31 (representing that black is ejected as 1 and white is ejected as 0) image data FC1 for the head F1. And the image data RC1 for the head R1 (pixels with a diagonal line rising to the right).
[0075]
As for the distribution order, the pixels (dots) to be ejected are sequentially distributed to the image data FC1 and the image data RC1 in the carriage movement direction with the upper left as the origin, and one line (first) in the main scanning direction (X direction). When the raster distribution is completed, the next raster (second raster) dot distribution is similarly performed by shifting one line in the direction (Y direction) opposite to the sub-scanning direction. However, the distribution destination of the top pixel is reversed from the first raster (that is, if the first raster distributes the top pixel to the head F1, the top pixel of the second raster is distributed to the head R1). The third raster is the same distribution destination of the first pixel as the first raster. The above is performed on the entire image.
[0076]
When the upper left is the origin, the carriage movement direction is the X direction, the direction opposite to the recording paper feeding direction is the Y direction, and the pixels are represented by the coordinate system of (X, Y), the first raster is the origin pixel (0, (0), (2,0), (5,0) are distributed to the head F1, and (1,0), (3,0) are distributed to the head R1. In the second raster, (2, 1) and (7, 1) are distributed to the head F1, (0, 1), and (4, 1) are distributed to the head R1. The recording dots (recording data) for 27 pixels in the 8 × 8 pixel area distributed in the same manner after the third raster are distributed to the head F1 for 15 pixels and to the head R1 for 12 pixels.
[0077]
Next, a specific configuration example of the SMS processing unit 32 will be described.
[0078]
FIG. 8 is a timing chart showing distribution in the SMS processing unit 32 in the image example of FIG. 1A, and FIG. 9 is a diagram showing a circuit example of the SMS processing unit 32.
[0079]
As shown in FIG. 8, the binary data C1 from the multi-value / binary conversion unit 31 is effective when the synchronization signals BVE1 and VE1 are both HIGH (also expressed as 1), and one HIGH section of BVE1 is one band. Image data for one raster, BVE1 is HIGH, and one HIGH section of VE1 includes image data for one raster. The synchronization signals BVE1, VE1 and the image data C1 are supplied from the multi-value / binary conversion unit 31 to the SMS processing unit 32 in synchronization with the rising edge of the clock 1T. BVE1 is synchronously processed at the fall of VE1. The distribution signal F / R * is a signal indicating that image data is distributed to the head F1 when HIGH and image data is distributed to the head R1 when LOW (also expressed as 0).
[0080]
In FIG. 9, 40 to 47 are flip-flops (hereinafter referred to as F / F), 48 and 49 are AND circuits, and 50 is an inverter. The F / F 40 outputs 1 when BVE1 = 0, and is synchronously processed at the falling edge of VE1. The output of the F / F 40 becomes the input of the F / F 41, and the F / F 41 is synchronously processed at the rise of 1T and is output as the distribution signal F / R *. That is, in the first raster immediately after BVE1 = 1, when the output of F / F40 is 1, F / R * = 1.
[0081]
Distribution signals F / R * and inverted signals of F / R * are ANDed with image data C1 by AND circuits 48 and 49, respectively, and synchronously processed at the fall of 1T by F / Fs 43 and 44, respectively. At 47, the signals are synchronously processed at the rise of 1T and output as FL1 and RL1, respectively. The inverted output of F / F43 is synchronously processed at 1T by F / F45, and then the inverted output of F / F44 is synchronously processed at 1T by F / F42. Input to the preset terminal (PR *) of F / F41. Therefore, when the image data C1 is distributed to FL1, F / F41 is cleared and F / R * = 0, and when the image data C1 can be distributed to RL1, F / F41 is preset and F / R * = 1. When the distribution of the SMS processing for the first raster is finished, the output of F / F 40 becomes 0 at the fall of VE1 at the end of the first raster, the output F / R * of F / F 41 becomes 0, the second The distribution destination of the first pixel of the raster is reversed. The second and subsequent rasters are distributed in the same manner as the first raster, and image data for one band is distributed. The SMS processing unit 32 registers the distributed image data FL1, RL1 in synchronization with the synchronization signals BVE1, VE1, 1T. Output to the adjustment unit 33.
[0082]
As described above, the image data C1 for one band is divided into the front recording image data FL1 and the back recording image data RL1 in the SMS processing unit 32, and the distributed image data FL1 and RL1 are registered respectively. The data is stored in the unit 33, read with a delay time corresponding to the registration adjustment, and input to the output control unit 34 as the image data FC1 and RC1.
[0083]
When performing four-pass printing, the output control unit 34 performs mask processing on the image data FC1 with the head F1 mask and the image data RC1 with the head R1 mask, as shown in FIG. 1B. Here, although the head F1 and the head R1 are referred to, the head F1 mask is also used for the other front-side heads F2 to F8, and the head R1 mask is the other back-side heads R2 to R2. Also used for R8.
[0084]
Specifically, the white pixels are passed as they are, the mesh pixels are set to 0 (empty), and the first image data for forward recording (hereinafter, the forward recording data of the front head is used as FFW image data, The data for the forward path recording of the rear head is referred to as RFW image data). Further, the mask is reversed, the pixels in the mesh portion are passed as they are, the pixels in the white portion are set to 0 (empty), and the second image data for backward recording (hereinafter, the forward recording data of the front head is referred to as FBW). Image data and data for forward recording of the rear head are referred to as RBW image data). In the figure, the mask for the head F1 is an inverted version of the mask for the head R1, but this is not restrictive. It is also possible to use the same mask.
[0085]
Further, in terms of the number of dots, as shown in FIG. 1A, the image data FC1 for the head F1 that ejects 15 pixels is distributed into the image data for FFW that ejects 8 pixels and the image data for FBW that ejects 7 pixels. The image data RC1 for ejecting head R1 is distributed into RFW image data ejecting 7 pixels and RBW image data ejecting 5 pixels.
[0086]
Here, a specific configuration example of the output control unit 34 will be described.
[0087]
FIG. 10 is a timing chart of operation signals when the output control unit 34 distributes image data in the image example of FIG. 1A, and FIG. 11 is a diagram illustrating an image data distribution circuit of the output control unit 34.
[0088]
The image data FC1 is read from the registration adjusting unit 33 in the BJ raster direction (a line corresponding to one band from the upper left end in the Y direction) in synchronization with the synchronization signals BJ_BVE and BJ_VE1, and is FFW by the signal ENB corresponding to the mask. The image data FFW1 and the FBW image data FBW1 are distributed. BJ_VE1 / 4 is inverted every 2 rasters of the BJ raster, ENB is a signal inverted every 2 pixels, and further inverted every 2 rasters depending on whether BJ_VE1 / 4 is 1 or 0. ENB = 1 corresponds to the white portion of the mask of FIG. 1B, and ENB = 0 corresponds to the mesh portion.
[0089]
In FIG. 11, 51 and 52 are counters, 53 and 54 are selectors, 55 and 56 are F / Fs, 57 to 60 are inverters, 61, 62, and 64 are AND circuits, and 63 is an OR circuit. The counter 52 divides BJ_VE1 by four and generates BJ_VE1 / 4 through the inverter 58, and BJ_VE1 / 4 is input to the selection terminal S of the selector 53. The counter 51 divides the pixel clock 1T by 4 and generates 1T / 4 via the inverter 57. The 1T / 4 and the inverted 1T / 4 * of T / 4 are input to the input terminals A and B of the selector 53, respectively. The
[0090]
Since the selectors 53 and 54 are Y = A when S = 1 and Y = B when S = 0, the output signal ENB of the selector 53 is formed as shown in FIG. The signal ENB is inverted by the inverter 59, and the inversion of ENB and ENB is input to the input terminals A and B of the selector 54, respectively, and is selectively controlled by the input signal MASK to the selection terminal S of the selector 54.
[0091]
The signal MASK is controlled by the CPU control unit 3 to invert the mask. When MASK = 0, the ENB is output from the output terminal Y of the selector 54, and the AND circuit 62 uses ENB as a mask signal for generating the image data FFW1. When MASK = 1, the ENB inversion is output from the output terminal Y of the selector 54, and the ENB inversion is input to the AND circuit 62 as a mask signal for generating the image data FBW1. The AND circuit 62 performs mask processing for 4-pass printing by performing AND processing on the signal from the output terminal Y of the selector 54, the input signal PASS, and the image data FC1.
[0092]
The input signal PASS is output from the CPU control unit 3 in accordance with the recording mode input by the user. If PASS = 0, the AND circuit 61 converts the 2-pass image data FC1 without performing the 4-pass recording mask process. To output from the output control unit 34, and to select the output of the image data FC1 with PASS = 1 and enabling the 4-pass from the output control unit 34 via the AND circuit 62.
[0093]
In the case of 2 passes, the image data is subjected to 1T inversion 1T * and 1T synchronization processing in the F / Fs 53 and 54 via the OR circuit 63 and the AND circuit 64 in both cases, and new BJ_VE1, FFW1 (or FBW1), Output in synchronization with BJ_VE1. In FIG. 10, FFW1 and FBW1 are described in parallel, but this is a description of output image data when MASK = 0 and MASK = 1, and FFW1 and FBW1 are not output at the same time. .
[0094]
The image data FC1 for recording with the head F1 has been described above. However, when the image data is distributed using an inverted mask for the head R1 as shown in FIG. 1B, the FW of the MASK signal is used for the image data RC1. And BW are reversed, FW when MASK = 1, and BW when MASK = 0. This can be dealt with by providing the signal MASK independently for the head F1 and the head R1 and setting them separately from the CPU control unit 3.
[0095]
However, the registration adjustment unit 33 controls the mask so that the origin of the lead is the upper left in the forward path and the upper right in the backward path. In order to easily switch the mask, the recording width W may be set to an integral multiple of the minimum unit of four pixels of the mask. In that case, it is not necessary to switch MASK between FW and BW for the head F1 and the head R1. (If the recording width W is divided by 4 and there are 2 pixels remaining, it is necessary to switch MASK between FW and BW of each head. If the recording width W is other than the above, fraction processing is also required for MASK).
[0096]
In the above description, the distribution of the image data using the mask is performed by the output control unit 34. However, the present invention is not limited to this.
[0097]
As another method, when the memory control unit reads out the image data from the connecting memory unit in the registration adjusting unit 33, the image data of the pixel masked according to the mask data can be replaced with non-recording data. This is a part of the function of the output control unit 34 transferred to the registration adjustment unit 33.
[0098]
Further, when the memory control unit reads the image data from the connecting memory unit in the registration adjusting unit 33, the image data of the pixel to be masked according to the mask data is replaced with non-recorded data without reading from the connecting memory unit. Can also respond. The memory control unit can respond by performing address control on the connecting memory unit in accordance with the mask data.
[0099]
<2-pass and 4-pass recording sequence>
The outline of the 2-pass and 4-pass recording sequences will be described with reference to FIGS.
[0100]
FIG. 12 is a diagram showing the flow of image data inside the image processing unit 11 in two-pass recording, FIG. 13 is a timing chart of the two-pass recording operation, and FIG. 14A shows a recording state in four-pass recording. FIG. 14B is a diagram showing a flow of image data inside the image processing unit 11 in the 4-pass printing, and FIG. 15 is a timing chart of the 4-pass printing operation.
[0101]
12A and 14B, (a) is a memory map of the image memory unit 30, (b) is a memory map of the head F1-side registration adjustment unit 33, (c) is a memory map of the head R1-side registration adjustment unit 33, ( d) is a diagram showing output data from the output control unit 34, and (e) is a diagram showing recording data by the recording head.
[0102]
The numbers 1, 2, 3,... Inside the rectangle of the image memory unit 30, the registration adjustment unit 33, and the output control unit 34 represent band numbers, the numbers -1, 2 inside the rectangle represent the upper and lower half bands, The numbers 1, 2, 3,... On the left side of the image memory unit 30 represent read positions (addresses), and the numbers 1, 2, 3,... On the left side of the registration adjustment unit 33 represent the write positions (addresses). .. And ← on the right side of the registration adjustment unit 33 represent read positions (addresses), α in the squares of the output control unit 34, the head F1, and the head R1 represents forward recording, and β represents In this case, A and B in the head F1 and C and D in the head R1 represent the upper half and the lower half of the nozzle to be recorded.
[0103]
13 and 15, PE is a signal representing the recording operation of one page, RD_START is a signal indicating the start of reading of the first band, BVE is a synchronization signal, and MT_START is the driving start of the first scan. BAND_TOP is a signal representing the recording start timing, and BVE_F1 to BVE_F8 and BVE_R1 to BVE_R8 are signals representing the recording operation of each recording head. The numbers in BVE, BVE_F1 to BVE_F8, and BVE_R1 to BVE_R8 represent the band numbers of the image data to be processed.
[0104]
FIGS. 13A, 15A, and B are timing charts from the start of recording to the progress of four bands, and FIGS. 13B, 15C, and D are timing charts of the progress of four bands and the end of recording.
[0105]
First, an outline of a two-pass recording sequence will be described with reference to FIGS. 7B, 12 and 13. When performing two-pass printing, as shown in FIG. 7B, the recording paper 19 is conveyed by one band width H each time the carriage unit 18 (FIG. 6) is scanned.
[0106]
Upon receiving a recording request, the CPU control unit 3 confirms that recording is possible (confirmation of whether there is image data in the image memory unit 30, etc.), then sets the PE to HIGH and sets one page (collection of a plurality of bands). Is notified to each unit (particularly the image processing unit 11).
[0107]
Next, the CPU control unit 3 sets the first band read address to the image memory unit 30, and sets the first band write address and the first scan read address to the registration adjustment unit 33. At this time, the read address for one scan from the registration adjustment unit 33 on the head F1 side is the same as the write address for the first band, but the inter-unit gap D = 2.5 × H. The read address for one scan from the registration adjusting unit 33 is set 2.5 bands before the write address of the first scan, that is, the −2.5 band.
[0108]
When the CPU control unit 3 sets the RD_START signal indicating the start of reading of the first band to the image memory unit 30 to a certain width HIGH (= 1), the image memory unit 30 starts the image data from the set read address. The PLT is read out, synchronized with the synchronization signals BVE, VE, and 1T, output to the multi-value / binary converter 31, and image data obtained through the processing of the multi-value / binary converter 31 and the SMS processor 32. Are written in the registration adjusting unit 33 from the set write address.
[0109]
After the CPU control unit 3 detects the end of reading of the first band from the image memory unit 30 at the falling edge of BVE, an MT_START signal indicating the start of driving of the first scan is given to the carriage motor driving unit 14 by a certain width HIGH. When (= 1), the carriage motor drive unit 14 drives the carriage motor 15 to perform one forward (FW) scan for the scan length corresponding to the recording width (X direction). In the scanning at this time, the carriage motor 15 is driven by a trapezoidal drive like a general stepping motor.
[0110]
The encoder unit 8 generates a phase signal AB by the movement of the carriage unit 18 and outputs the phase signal AB to the output control unit 34. The output control unit 34 detects the position of the carriage unit 18 from the phase signals A and B (the position origin is set as the home position). HP). Here, assuming that the resolution of the encoder unit 8 is 0.5 μm and the resolution of the recording head is 70.5 μm, the output control unit 34 generates a square wave ENC_CK of 0.5 μm cycle from the phase signals A and B, and sets ENC_CK to By counting with the up / down counter, the position of the carriage unit 18 is detected in units of 0.5 μm. By counting 141 ENC_CK, a 70.5 μm cycle square wave ENC_VE is generated, and ENC_VE is synchronized with the image clock 1T. In addition, a synchronization signal BASE_VE is generated in which a HIGH period is given a width of 1T (here, 1408 pixels). This BASE_VE is the basis for generating BJ_VE delayed by the registration adjusting unit 33 according to the registration of each recording head.
[0111]
When the output control unit 34 detects a preset recording start position by detecting the position by counting ENC_CK and sets the BAND_TOP signal indicating the recording start to a certain width HIGH (= 1), the registration adjusting unit 33 The synchronization signals BVE_F1 to BVE_F8 and BVE_R1 to BVE_R8 are generated by providing delay times corresponding to the registration adjustment values such as the head gap d of each head. Since the first scan is forward (FW) recording, the smaller one of the recording heads F1 to F8 and R1 to R8 (the one on the right in FIG. 7A) is recorded first in time. For this reason, the delay time of the synchronization signals BVE_F1 to F8 and BVE_R1 to R8 having a larger number (the one on the left in FIG. 7A) becomes longer. On the other hand, in the return pass (BW) recording, the one with the smaller number of the synchronization signals BVE_F1 to F8 and BVE_R1 to R8 (the one on the right in FIG. 7A) has a longer delay time. In the first scan, since the head R1 is dummy image data that is not effective image data, the output controller 34 masks image data for one band of the head R1.
[0112]
When the CPU control unit 3 detects the end of recording of the first scan by a handshake with the output control unit 34, the CPU control unit 3 sends a transport request for one band to the transport motor driving unit 16, and the transport motor driving unit 16 The motor 17 is driven for one band to feed the recording paper 19 for one band. On the other hand, the carriage 18 is automatically stopped by the carriage motor drive unit 14.
[0113]
During the first scan recording, the CPU control unit 3 reads the image data of the second band from the image memory unit 30 and writes it to the registration adjustment unit 33 as in the case of the first band.
[0114]
This completes the recording of one scan.
[0115]
Thereafter, in the second and subsequent scans, the read address of the image memory unit 30 and the read address and write address of the registration adjustment unit 33 are each advanced by one band, and the same processing is performed.
[0116]
However, in the first, third, and fifth bands (odd scan), forward (FW) recording is performed, and in the second, fourth, sixth, and so on (even scan), backward (BW) recording is performed. Further, the output control unit 34 performs output masking of dummy data at the leading and trailing edges of the page with the inter-unit gap D (2.5 band in the description) between the head F1 and the head R1. Specifically, in the front end processing, all bands of the first and second scans of the head R1 and the upper half band of the third scan are output masked, and the image data is replaced with 0 (empty). In the rear end processing, the head F1 The lower end is masked by the extra e at the nth scan (n = 4 in FIG. 12), the entire band is masked at the n11th and n + 2th scan, and the lower half band + the extra e is masked at the n + 2th scan of the head R1. To do.
[0117]
In this way, an image is formed by superimposing recording by the head F1 and recording by the head R1, as shown in FIG. At this time, the reciprocal combination with the heads of the first band and the second band is not constant, and the combination is repeated in a two-band cycle. In FIG. 12, the 1-1 band is A-α, D-α, the 1-2 band is B-α, C-β, the 2-1 band is A-β, D-β, the 2-2 band. The eyes are repeated in the order of B-β and C-α. In order to eliminate the half-band unevenness caused by this, the present invention proposes 4-pass printing. In this embodiment, the user can select the 4-pass printing mode when priority is given to image quality. It can be configured.
[0118]
The four-pass recording operation will be described with reference to FIGS. 14A, 14B, and 15.
[0119]
The outline is the same as that of the two passes, but the recording paper is transported by half a band for each scan as shown in FIG. 14A. 14B (a), (b), and (c) have the following differences.
[0120]
1) Writing from the image memory unit 30 to the registration adjusting unit 33 is not performed during odd scans, but only during even scans (including 0 scans).
[0121]
2) The read address of the first scan from the registration adjustment unit 33 on the head F1 side is set to a half band (−0.5 band) before the write address of the first band, and the registration adjustment unit 33 on the head R1 side The read address for the first scan is set 3 bands before the write address for the first band (−3 band). Further, the read address from the registration adjustment unit is updated every half band.
[0122]
3) The number of scans is 2n + 6 with respect to the number of bands n of the image to be recorded.
[0123]
4) In the tip processing, the upper half band of the first scan of the head F1 is masked, and all of the first, second, third, fourth, and fifth scan bands of the head R1 and the upper half band of the sixth scan are masked.
[0124]
5) In the rear end processing, the second n scan of the head F1 is masked with the remainder e and the half band of the 2n + 1 scan + the remainder e and the entire band of 2n + 2 to 2n + 6 scan, and the remainder of the 2n + 5 scan of the head R1. Mask the minute e and the half band of the 2n + 6th scan + the remainder e.
[0125]
6) Make the transport half a band each time.
[0126]
Because of these differences, the timing chart at the start and end of recording is as shown in FIG.
[0127]
As described above, when performing reciprocal recording with two-stage heads, the SMS processing is performed, so that each head can be used equally. Further, since the conveyance is performed for a half band and the image data is distributed by the forward recording and the backward recording by the mask, as shown in FIGS. 14B (d) and 14 (e), the forward recording of the front head and the front recording are performed for all lines. An image is formed by superimposing four scans of the head backward recording, the back head forward recording, and the back head backward recording. As a result, the influence of the difference in the recording characteristics between the forward recording and the backward recording becomes difficult to appear in the image, and there is an effect of not only suppressing the non-ejection of nozzles and the influence of twisting but also suppressing the conventional half-band unevenness.
[0128]
In this embodiment, since the 4-pass printing is performed through the two steps of the SMS process and the mask process, it is possible to easily switch to the 2-pass printing only with or without the mask process.
[0129]
Here, an example has been described in which two recording heads for the same ink color are arranged apart from each other in the paper conveyance direction, but the present invention is not limited to this.
[0130]
For example, as shown in FIG. 24, two recording heads for the same ink color may be arranged continuously in the carriage movement direction (main scanning direction) (without being separated in the paper conveyance direction). Hereinafter, distribution of image data in this case will be described.
[0131]
In FIG. 24, a first head unit (front head unit) 12 has recording heads F1 to F8, and a second head unit (back side head unit) 13 has recording heads R1 to R8. In comparison with FIG. 7A, the inter-unit gap D is set to “0”, and the rear head unit 13 is arranged in the carriage movement direction (main scanning direction) instead of the conveyance direction (sub scanning direction). For this reason, the recording position adjustment (registration alignment) between the head units 12 and 13 in the carriage movement direction corresponds to the control of the registration adjusting unit 33 and the output control unit 34 in FIG. In the SMS processing by the SMS processing unit 32, the image data is equally distributed to the recording heads F1 to F8 of the first head unit 12 and the recording heads R1 to R8 of the second head unit 13 as described above.
[0132]
As in the previous example, the mask processing in the output control unit 33 is used to distribute image data for forward pass recording and backward pass recording, and to carry a half band. As a result, as shown in FIG. 25, the four head scans of the first head, the first head, the second head, the second head, and the second head are recorded on all lines. An image is formed by the alignment. In FIG. 25, for the sake of easy understanding, the recording of the first head and the recording of the second head are shown separately for the sake of convenience, but they overlap in actual recording.
[0133]
As described above, even when two recording heads for the same ink color are continuously arranged in the main scanning direction, by applying the present invention, the influence due to the difference in the recording characteristics between the forward recording and the backward recording appears in the image. This not only suppresses the effects of nozzle ejection failure and twist, but also has the effect of suppressing conventional one-band unevenness.
[0134]
Note that the order of the forward recording and the backward recording for each half-band area is reversed in half-band units, but the influence on the image quality due to this order is small.
[0135]
As can be understood from the above, even if the inter-unit gap D between the two heads arranged apart in the transport direction is not (2n + 1) × H / 2, the registration adjusting unit 33 and the output control unit 34 It is possible to realize four-pass printing by control, and in this case, the same effect can be obtained.
[0136]
<Internal configuration and control method of recording head>
Next, how the recording head ejects ink from the nozzles corresponding to the image data input from the output control unit 34 will be described in detail. The following description applies to all the recording heads of this apparatus.
[0137]
FIG. 2 is a diagram illustrating the internal configuration of the recording head and the time-division driving method.
[0138]
FIG. 16 is a circuit diagram showing a part of the internal configuration of the recording head.
[0139]
FIG. 17 is a timing chart for explaining the control of the recording head.
[0140]
As shown in FIG. 2A, the number of nozzles in each of the recording heads in this embodiment is 1408. The 1408 nozzles are divided into 11 blocks (called chips) in units of 128 nozzles. However, among 1408 nozzles, 1360 nozzles 25 to 1384 are referred to as effective nozzles, and among 1360 effective nozzles, continuous 1344 nozzles are referred to as recording nozzles (in FIG. 2, 1344 nozzles 33 to 1376 are recorded). In actuality, only the recording nozzle forms a recorded image in the recording operation. The difference 16 between the effective nozzle 1360 and the recording nozzle 1344 is used for registration adjustment (referred to as vertical registration adjustment) in the recording paper conveyance direction. Note that the vertical registration adjustment is performed by a relative shift between the image data that has been used for the 2-pass or 4-pass by the output control unit 34 and the synchronization signal BJ_VE. Specifically, the image data in the BJ_VE enable (HIGH) section has 1408 pixels, but the recorded image is 1344 pixels and the preceding and succeeding 32 pixels are non-recorded data 0, and this recorded image is recorded according to the vertical registration adjustment amount. This is done by setting the amount to be delayed or advanced by the clock 1T with respect to BJ_VE.
[0141]
FIG. 16 mainly shows the configuration in the chip 11 of the recording head. In FIG. 16, 70 is a 128-bit shift register, 71 is a 128-bit data latch that latches 128 bits of the shift register 70, 72 to 79 are AND circuits, 80 to 83 are OR circuits, and 84 is 4 inputs and 16 outputs. Decoders, 85 to 88 are AND circuits, 89 to 92 are transistor circuits, and 93 to 96 are heat portions corresponding to the respective nozzles. The bases of the transistor circuits 89 to 92 are respectively connected to the outputs of the AND circuits 85 to 88, the emitter side is connected to a heat ground HGND (a ground paired with the heat power supply), and the collector side is connected to the heat units 93 to 96, respectively. One of the heat parts 93 to 96 is connected to the heat power source VH.
[0142]
One input of the AND circuits 85 to 88 is connected to the output of the decoder 84, and the input of the decoder 84 is a signal HT_ENB 0 to 3, which is a signal for shifting the ejection timing of ink from the nozzles 1281 to 1408.
[0143]
The other inputs of the AND circuits 85 to 88 are connected to the outputs of the OR circuits 80 to 83, respectively. The OR circuits 80 to 83 output 1 when the image data of MH11 and MH_ENB11 and their nozzles are all 1 or when the image data of PH11 and PH_ENB11 and their nozzles are all 1. Here, PH11 and MH11 represent preheat and main heat of the chip 11 (so-called double-pass heat system). MH_ENB11 is a main heat enable signal and a preheat enable signal for the chip 11.
[0144]
Outputs ENB0 to ENB15 of the decoder 84 are periodically connected in units of 16 nozzles from the AND circuit 88 of the nozzle 1281 of the chip 11 to the AND circuit 87 of the nozzle 1296.
[0145]
In this figure, of the nozzles 1281 to 1408, only the nozzles 1408 and 1393, 1296, and 1281 are representatively shown, and the rest are omitted because they are the same. Further, since the other chips 1 to 10 are the same as the chip 11, the description thereof is omitted.
[0146]
In each of the chips 1 to 11, CLK, IDATA, D_LAT, HT_ENB0 to 3, HGND, and VH are common, and in particular, IDATA is connected to the output ODATA of the preceding chip. Accordingly, the image data is transferred between the shift registers 70 to the chips 11 to 1.
[0147]
Next, the data transfer operation and the drive operation will be described with reference to FIGS. FIG. 17 is a timing chart of drive signals for the recording head F1 when performing two-pass recording.
[0148]
The head drive units 20 and 21 are image data FH1 to FH8 and RH1 to RH8 (or FFW1 to FFW8, FBW1 to FBW8, RFW1 to RFW8, RBW1 to RBW8) for each recording head from the image processing unit 11, and a synchronization signal. When receiving BJ_BVE_F1 to BJ_BVE_F8, BJ_BVE_R1 to BJ_BVE_R8, BJ_VE_F1 to BJ_VE_F8, BJ_VE_R1 to BJ_VE_R8 and the image clock 1T, the driving operation for transferring and discharging the image data is independently performed for each recording head. .
[0149]
The head drive unit of F1 connects the image data FH1 to the IDATA of the head F1, and connects a signal obtained by ANDing the image clock 1T, BJ_BVE1, and BJ_VE1 to the CLK of the head F1. First, the image data F1 of the first BJ raster (here, 1408 pixels) is transferred to the shift register 70 (chips 1 to 11) in synchronization with the fall of CLK.
[0150]
This data F1 is latched by the data latch 71 (chips 1 to 11) until the one-shot (width 1T) D_LAT signal after the falling edge of BJ-VE1 during the HIGH period of BJ_BVE1, and the next BJ_VE1 HIGH period The recording drive is performed in accordance with the image data of the first BJ raster latched while transferring the BJ raster in the same manner, and thereafter recording is performed in units of each BJ raster.
[0151]
When the image data is 1, MH_ENB1 to 11 = 1, MH1 to 11 = 1, and any one of the outputs ENB0 to ENB15 of the decoder 84, any of the outputs of the AND circuits 85 to 88 is 1. Thus, the corresponding ones of the transistor circuits 89 to 92 are turned on, the current flows through the corresponding ones of the heater units 93 to 96, the heater unit through which the current flows generates heat, and ink is ejected from the corresponding nozzles. Here, in order to simplify the description, signals common to all chips are input to MH_ENB1 to 11 and PH_ENB1 to 11, and signals common to MH1 to 11 are also used to signals PH1 to 11. HT_ENB0 to 3 are signals for instructing the order for shifting the ejection timing in the BJ raster, and are used in the time-division driving method.
[0152]
<Time division drive method of recording head>
When the ejection of ink from the nozzles is controlled for each chip in the circuit as described above, 128 nozzles in one chip are divided into 16 consecutive nozzles, and the 16 nozzles receive ink at different timings. Discharge. Conventional time-division driving is a technique for reducing the load of the power source by reducing the peak value of the current required for driving the recording head, but the time-division driving method according to the present embodiment is further adjacent. By driving the nozzles at significantly different timings, the influence of ink vibration in the head accompanying the ejection of ink droplets is reduced, and the ink ejection characteristics of the head are improved.
[0153]
With reference to FIG. 2B, FIG. 16, FIG. 18, and FIG. 19, the time division drive method of the recording head will be described with one recording head F1 as a representative.
[0154]
FIG. 18 is a timing chart illustrating time-division driving of the recording head when performing two-pass recording.
[0155]
FIG. 19 is a control circuit diagram for generating a signal necessary for time-division driving in 2-pass printing.
[0156]
In FIG. 2B, the horizontal axis is the time axis, and the vertical axis is the position of 16 nozzles. FIG. 2B shows that, among the 128 nozzles present in one chip, ink is ejected from 16 consecutive nozzles at different timings. Assuming that 16 consecutive nozzles are nozzles 1 to 16 in order as shown in (a), the nozzle 1 is first driven, the nozzle 1 is followed by the nozzle 10, the next is the nozzle 3, the next is the nozzle 12, and the Next, the nozzles 5 are driven in order such as. That is, the discharge order of 16 consecutive nozzles (nozzles 1 to 16) is nozzles 1, 10, 3, 12, 5, 14, 7, 16, 9, 2, 11, 4, 13, 6, 15, and 8. is there. Therefore, the difference in the ejection order between adjacent nozzles in one head is ± 1 of half the number of nozzles 16, that is, 7 or 9, and the interval between nozzles that eject simultaneously is 16.
[0157]
Here, only 16 continuous nozzles have been taken out and explained. However, considering the regularity of the driving nozzle macroscopically, the nozzle 10 (that is, 1 + 9) is driven next to the nozzle 1, and the nozzle 10 is followed by the nozzle. Nineteen nozzles ahead are driven, such that 19 (ie 10 + 9) is driven and nozzle 19 is followed by nozzle 28 (ie 19 + 9). However, since there are nozzles that are driven at the same timing for every 16 nozzles, for example, the nozzle 3 (that is, 19-16), the nozzle 35 (that is, 19 + 16),.. That is, the nozzle group represented by the nozzle (19 + 16 × i) is driven simultaneously (where i is an integer). Therefore, in one head, 88 nozzles separated by 16 nozzles are discharged simultaneously.
[0158]
The generation and timing of signals related to time-division driving (particularly HT_ENB0 to 3) will be described below with reference to FIGS.
[0159]
Signals HT_ENB0 to 3 for designating the order of division driving to the recording head are represented by 4-bit data with HT_ENB3 as the most significant bit, and as shown in FIG. 18, 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12, 5, 14, 7 and so on. According to the generated HT_ENB0 to 3, ENB0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12, 5, 14, 7 are sequentially 1 by the decoder 84 in the recording head F1. (Active), the nozzles 1, 10, 3, 12, 5, 14, 7, 16, 9, 2, 11, 4, 13, 6, 15, and 8 are sequentially driven to eject ink. Similarly to the 16 nozzles, 88 blocks are simultaneously driven in one recording head F1. Similarly, the following BJ raster is also divided and driven.
[0160]
FIG. 19 shows a signal generation circuit. In the section of BJ_VE1 = 1, the counter 101 divides 1T (here, the frequency is 10 MHz) to generate ENB_CK (here, the frequency is divided by 80 and the frequency is 125 kHz) (FIG. 19A). This ENB_CK defines the cycle of division driving. Here, since the frequency is 125 kHz, the cycle is 8 μS. The rising edge of ENB_CK is synchronized with the rising edge of BJ_VE1 = 1. It is important that the cycle Tf of the BJ_VE1> the image data transfer time Ts> the total time Th of the divided drive. For the sake of explanation, Th = 8 μs × 16 = 128 μs, Ts = 1408/10 MHz = 140. It is assumed that 8 μs and Tf = 1/4 kHz = 250 μs.
[0161]
When this ENB_CK is up-counted by the counter 102 (synchronous clear 4-bit up counter), the counter output (the least significant bits Qa, Qb, Qc, Qd) changes to 0, 1, 2, 3,... 15 and Qa is changed to HT_ENB0. , Qb are output as HT_ENB1, and Qc is output as HT_ENB2. As HT_ENB3, it is assumed that the selector 105 selects Qa or a signal obtained by inverting Qa by the inverter 104 (FIG. 19B).
[0162]
The selection signal S of the selector 105 uses the output Qd of the counter 102, Qd = 0 in the first half ENB_CK eight sections, the selector 105 selects the B side, Qa is output as HT_ENB3, and Qd = 8 in the second ENB_CK section. 1, the selector 105 selects the A side, and the inversion of Qa is output as HT_ENB3 (refer to FIG. 18 for the waveforms of HT_ENB0 to 3).
[0163]
The ripple carry RCO from the counter 102 is output to the 16th ENB_CK (count value is 15), and is used as a signal for clearing CNT_ENB to 0 in the circuit 103. CNT_ENB is set to 1 when BJ_BVE1 = 1 and BJ_VE1 = 1. Also, CLR * in which CNT_ENB is synchronized with the falling edge of ENB_CK is generated by the circuit 103 and input to the CLR * terminal of the counter 102. By such a circuit, HT_ENB0 to 3 in 1BJ raster are 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12, 5, 14 in FIG. , 7 as a signal representing a sequence of numbers.
[0164]
Here, the generation of HT_ENB0 to 3 is performed by a logic circuit such as a counter, but the generated data 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12, HT_ENB0 to 3 can also be generated by storing 5, 14, and 7 and reading them in synchronization with the synchronization signals BJ_BVE1, BJ_VE1, and ENB_CK.
[0165]
The generation of other signals used for the recording head F1 will also be briefly described.
[0166]
As shown in FIG. 19C, the image data transfer clock CLK is generated by ANDing BJ_BVE1, BJ_VE1, and 1T in the AND circuit 106.
[0167]
As shown in FIG. 19D, the signal D_LAT for latching the image data in the data latch 71 is obtained by ANDing the signal obtained by shifting BJ_BVE1 by one at the rising edge of BJ_VE1 by the flip-flop 107 and BJ_VE1 by the AND circuit 108. This is a signal generated by the inverter 109, the flip-flop 110, and the AND circuit 111 from the falling edge of the signal.
[0168]
As the main heat enable signals MH_ENB1 to 11 and the preheat enable signals PH_ENB1 to 11, signals obtained by shifting the output of the flip-flop 107 by one fall of BJ_VE1 by the flip-flop 113 are shown here for simplicity. Is used.
[0169]
Further, as shown in FIG. 19 (e), the main heat signals MH <b> 1 to 11 and the preheat signals PH <b> 1 to 11 are generated by the pulse generation circuit 114. Although the detailed circuit is omitted, the generation timing is based on the rising edge of ENB_CK in the section of CNT_ENB = 1, and a waveform as shown in FIG. 18 is generated in each divided drive (8 μs) with a resolution of 1T (10 MHz). Cycle). The pulse width, the interval between the main heat and the preheat, and the like are set in advance from the control unit 5. Attention here is to set the main heat and preheat so as to be within 8 μs cycle.
[0170]
<High-speed 4-pass mode>
When time-division driving is performed during 4-pass printing, if the nozzle is driven at the same ejection timing as in FIG. 2B, as shown in FIG. 2C, 0, 1, 4, 5, 8 with 1 BJ raster. , 9, 12, and 13 (or timings of 2, 3, 6, 7, 9, 10, 14, and 15), ink is ejected from the nozzles. That is, it can be seen that the time division driving is performed in 8 divisions using 16 pulses.
[0171]
On the other hand, if the timing of time division at the time of 4-pass recording is changed as shown in FIGS. 2C and 2D in accordance with the mask shown in FIG. 1B, 1BJ raster recording is performed with 8 pulses. be able to. Therefore, high-speed recording is possible by changing the scanning speed of the carriage twice without changing the division driving cycle. As a result, it is possible to eliminate a decrease in the recording speed when compared with the two-pass recording, and it is possible to improve the image quality by the four-pass recording at a recording speed substantially the same as the two-pass recording.
[0172]
A method for performing four-pass printing at high speed by applying the time-division driving will be described below with reference to FIGS. 2 (d), 2 (e), 3 and 20.
[0173]
FIG. 3 is a timing chart for explaining the division driving method in the high-speed recording of the recording apparatus.
[0174]
FIG. 20 is a control circuit diagram for generating signals necessary for performing time-division driving in 4-pass printing.
[0175]
In the double speed mode, the control unit 5 instructs the carriage motor drive unit 14 to double the rotation speed in the trapezoidal drive constant speed region, and the carriage motor drive unit 14 passes the carriage motor 15 through the carriage unit. The encoder unit 8 detects the movement of the carriage unit 18 and generates a synchronization signal BASE-VE. Here, the moving speed in the normal mode is 282 mm / s in the product of the frequency 4 kHz of BASE_VE (same for BJ_VE1) and the resolution 70.5 μm, but 564 mm / s in the double speed mode, and BASE_VE (same for BJ_VE1) is 8 kHz. It becomes. Therefore, it is important that the cycle Tf / 2 of the BJ_VE1> the image data transfer time Ts / 2> the total time Th / 2 of the divided drive, where Th / 2 = 8 μs × 8 = 64 μs, Ts = It is assumed that 1408/20 MHz = 70.4 μs and Tf = 1/8 kHz = 125 μs. That is, the number of divided drives is halved from 16 to 8, and the image transfer rate is doubled from 10 MHz to 20 MHz.
[0176]
In the double speed mode, the control unit 5 instructs the generation unit of the image clock 1T (in the image memory unit 30 and the output control unit 34) to generate 1T of double frequency (here, 10 MHz is changed to 20 MHz). The image processing unit 11 performs the same processing in synchronization with the double speed 1T (20 MHz). For this reason, the image processing unit 11 performs parallel processing by using a fast electric element so that it can operate even when the operation speed is double. Further, the control unit 5 notifies the head driving units 20 and 21 that the mode is the double speed mode, and the head driving units 20 and 21 perform high-speed division driving (thinning division driving) as described below.
[0177]
In the double speed mode, the division driving is alternately switched in units of 2BJ rasters according to the mask in FIG. 1B. In the double speed mode division drive timing of FIG. 3, the 1BJ raster and the 3BJ raster are described, the 2BJ raster is the same as the 1BJ raster, and the 4BJ raster and the 3BJ raster are the same. In the 1BJ raster, the divided drive control signals HT_ENB0 to 3 are sequentially generated as 0, 9, 4, 13, 8, 1, 12, and 5, so that the nozzles 1, 10, 5, and 14 as shown in FIG. , 9, 2, 13 and 6 are divided, and if the image data is 1 at that nozzle, ink is ejected. Nozzles 3, 4, 7, 8, 11, 12, 15, and 16 for which division driving is invalid do not discharge regardless of image data. In the 3BJ raster, HT_ENB0 to 3 are sequentially generated as 2, 11, 6, 15, 10, 3, 14, and 7, so that nozzles 3, 12, 7, 16, 11, 4, 15, and 8 are sequentially generated. Split drive is enabled. Since the mask is controlled to toggle every scan, HT_ENB0 to 3 are sequentially generated as 0, 9, 4, 13, 8, 1, 12, 5 during the first 1BJ raster recording, or 2, 11, 6, 15, 10, 3, 14, and 7 are sequentially switched for each scan.
[0178]
A method of generating HT_ENB0 to 3 will be described with reference to FIG. First, the counter 101 divides 1T (here, a frequency of 20 MHz for double speed) in a section of BJ_VE1 = 1 to generate ENB_CK (here, divide by 80 to obtain a frequency of 250 kHz). The ENB_CK for two clocks defines the cycle of division driving. When this ENB_CK is up-counted by the counter 120 (synchronous clear 4-bit up counter), the counter output (the least significant bits Qa, Qb, Qc, Qd) changes to 0, 1, 2, 3-15, and Qb is changed to HT_ENB0. Qc is set to HT_ENB2, HT_ENB3 is selected by the selector 122 as to whether Ob or Qb is inverted by the inverter 121, and HT_ENB1 is generated by the circuit 123 at the BJ raster count. The selection signal S of the selector 122 uses the output Qd of the counter 120, Qd = 0 in the first half ENB_CK, and the selector 122 selects the B side, Qb is output as HT_ENB3, and Qd = 8 in the second ENB_CK section. 1, the selector 122 selects the A side, and the inversion of Qb is output as HT_ENB3. The ripple carry RCO from the counter 120 is outputted to the 16th ENB_CK (count value is 15), and the circuit 123 clears CNT_ENB to 0 in accordance with the output of the RCO.
[0179]
In the circuit 123, CNT_ENB is set to 1 when BJ_BVE1 = 1 and BJ_VE1 = 1. Also, CLR * is generated by synchronizing CNT_ENB at the falling edge of ENB_CK. CLR * is input to the CLR * terminal of the counter 120. The circuit 123 toggles HT_ENB between 0 and 1 every 2 BJ rasters by counting BJ_VE1 while BJ_BVE1 = 1. The initial value of this toggle is determined by a signal MASK indicating mask inversion / non-inversion. The initial value is 0 when MASK = 0, and the initial value is 1 when MASK = 1. As a result, mask inversion is performed according to the value of the signal MASK.
[0180]
In this way, the waveforms of HT_ENB0 to HT_ENB3 are also generated as shown in FIG. 3 in the 1BJ raster. From these values, HT_ENB0 to 3 are 0, 9, 4, 13, 8, 1, 12, 5 And change.
[0181]
HT_ENB0 to 3 are generated by a logic circuit such as a counter, but 0, 9, 4, 13, 8, 1, 12, 5 and 2, 11, 6, 15, 10, 3, 3 are generated as data generated in the semiconductor memory. HT_ENB0 to 3 can be generated by storing 14, 7 and 2 groups, deciding which group is to be read in the product by MASK, and reading at the timing with the synchronization signals BJ_BVE1, BJ_VE1, ENB_CK.
[0182]
The generation circuits of the other signals used for the recording head F1, CLK, D_LAT, PH_ENB1 to 16, and MH_ENB1 to 16 are the same as those in the normal speed mode, but the period of the generated waveform is halved. On the other hand, PH1 to 11 and MH1 to 11 are generated by dividing 1T by 2 in the pulse generation circuit because 1T has a double frequency.
[0183]
Thus, since the ratio between the total time of the divided drive and the cycle of BJ_VE1 is constant at Th / Tf (in the description, 128/250) in both the normal mode and the double speed mode, ink droplets for 1 BJ raster by divided drive Is not changed in the X direction ((c) and (d) in FIG. 2). Further, as shown in FIG. 2 (d), the normal speed mode and the landing position can be made similar by shifting the division driving start when MASK = 1 with respect to BJ_VE1 (delaying to the right by ENB_CK1 cycles).
[0184]
In order to simplify the explanation regarding the division drive, the forward recording has been described as an example. However, when performing the backward recording, the registration adjusting unit 33 sets the origin of the lead to the reciprocal recording so that the forward path is at the upper left. Since the return path is on the upper right, if the recording width W is a multiple of 4 pixels, it is not necessary to invert the mask in the forward and return paths, and the initial value of HT_ENB1 is the same. When the recording width W is divided by 4, when 2 pixels remain, it is necessary to switch the signal MASK between the forward recording and the backward recording. If the recording width W is other than the above, fraction processing is required. However, since the mask of the head R1 is an inversion of the mask of the head F1, the value of the signal MASK is changed so that the initial value of HT_ENB1 is reversed from that of the head F1.
[0185]
Further, in order to make the landing position the same in the reciprocating recording, it can be dealt with by changing the order of the divisional driving in the backward path to the forward path. In the return path, the division drive 5, 12, 1, 8, 13, 4, 9, 0 in the 1BJ raster, the division drive 7, 14, 3, 10, 15, 6, 11, 2, and the final BJ line in the 3BJ raster The division drive is the same as the 3BJ raster. HT_ENB0 to 3 that specify the order of BW division driving can also be generated by a circuit similar to HT_ENB0 to 3 of FW. Specifically, HT_ENB0,2 of BW is the inversion of HT_ENB0,2 of FW, and HT_ENB1,3 of BW is the same as HT_ENB1,3 of FW.
[0186]
FIG. 21 shows another example of a circuit that can be used as part of the internal configuration of the recording head. The basic part is the same as in FIG. 16, except that two 64-bit shift registers 130 and 131 are provided in one chip, and two input terminals for image data are IDATA1 and IDATA2. The shift register 130 stores the image data of the first, second, fifth, sixth,... Pixels in two pixel cycles so as to correspond to the four-pass mask, and the shift register 131 stores the third, fourth, seventh, eighth,. The image data of the pixel is stored, and the data latch 132 associates the image data of the shift registers 130 and 131 with the nozzles 1281 to 1408. Since there are two registers / 2 input terminals, the transfer CLK of image data to the recording head can be handled without changing to the normal frequency. Further, by reading out only necessary data from the registration adjusting unit 33 of the image processing unit 11, even when the double speed mode is set, it is possible to cope with the image processing and transfer speed from the registration adjusting unit 33 to the recording head without doubling. On the other hand, since the processing from the image memory unit of the image processing unit 11 to the writing of the registration adjustment unit 33 is only one band processing in one scan every two scans in four passes, when in the double speed mode, By extending the processing time so as to process one band between two scans, it is not necessary to speed up image processing. Therefore, when such a circuit is provided, it is not necessary to use fast electrical elements or perform parallel processing, and the hardware configuration having the same capability as that conventionally used for two-pass recording has double speed. 4 pass recording becomes possible.
[0187]
In the above embodiment, in order to perform four-pass recording, the SMS processing unit distributes the recording data, and the output control unit uses the mask for images for forward recording and backward recording. Although the data is distributed, the means for distributing the four image data is not limited to this, and a method using four types of masks may be used. By performing the SMS process, the print head can be used evenly, and by combining this with the mask process, switching to the 2-pass print mode is facilitated. Further, in the description of the time division driving, only the case of the 16 division driving is shown, but the time division driving applicable to the present invention is not limited to this, and may be eight division driving or four division driving.
[0188]
When the time-division driving performed in the above embodiment is generalized, ink is ejected from the (9 × k + 1) + 16 × i = s-th nozzle, and 0, 1, 2, 3,... In this case, the change in s is the change in the nozzles that discharge continuously. However, i is an integer.
[0189]
Further, when generalized to cases other than the 16-division drive, the second nozzle that drives the nozzles simultaneously at intervals of 2 n and continuously drives the drive of a certain first nozzle is the first nozzle. Counting from any one of the nozzle groups ((2 to the nth power) / 2 + 1) + (2 to the nth power) × i time-division drive control so as to be positioned is the continuous ejection in time It is possible to evenly distribute both the spatial arrangement of the nozzles to perform and the temporal arrangement in which ejection is performed from the spatially adjacent nozzles.
[0190]
In the above embodiments, the liquid droplets ejected from the recording head have been described as ink, but the liquid droplets are not limited to ink. For example, it may be a treatment liquid that is ejected to a recording medium in order to improve the fixability and water resistance of the recorded image or to improve the image quality.
[0191]
The above embodiment includes means (for example, an electrothermal converter, a laser beam, etc.) that generates thermal energy as energy used for performing ink discharge, particularly in the ink jet recording system, and the ink is generated by the thermal energy. By using a system that causes a change in the state of recording, it is possible to achieve higher recording density and higher definition.
[0192]
As its typical configuration and principle, for example, those performed using the basic principle disclosed in US Pat. Nos. 4,723,129 and 4,740,796 are preferable. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal corresponding to the recording information and applying a rapid temperature rise exceeding the film boiling to the electrothermal transducer, the thermal energy is generated in the electrothermal transducer, and the recording head This is effective because film boiling occurs on the heat acting surface of the liquid, and as a result, bubbles in the liquid (ink) corresponding to the drive signal on a one-to-one basis can be formed. By the growth and contraction of the bubbles, liquid (ink) is ejected through the ejection opening to form at least one droplet. When the drive signal is pulse-shaped, the bubble growth and contraction is performed immediately and appropriately, and thus it is possible to achieve the discharge of liquid (ink) with particularly excellent responsiveness.
[0193]
As this pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further excellent recording can be performed by employing the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface.
[0194]
As the configuration of the recording head, in addition to the combination configuration (straight liquid flow path or right-angle liquid flow path) of the discharge port, the liquid path, and the electrothermal transducer as disclosed in each of the above-mentioned specifications, the heat acting surface The configurations using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose a configuration in which is disposed in a bending region, are also included in the present invention. In addition, Japanese Patent Application Laid-Open No. 59-123670, which discloses a configuration in which a common slot is used as a discharge portion of an electrothermal transducer, or an opening that absorbs a pressure wave of thermal energy is discharged to a plurality of electrothermal transducers. A configuration based on Japanese Patent Laid-Open No. 59-138461 disclosing a configuration corresponding to each part may be adopted.
[0195]
The recording head used in the above embodiment is not only a cartridge type recording head in which an ink tank is integrally provided, but also an electrical connection with the apparatus main body and an apparatus by being mounted on the apparatus main body. A replaceable chip type that can supply ink from the main body may be used.
[0196]
In addition, it is preferable to add recovery means, preliminary means, and the like for the recording head to the configuration of the recording apparatus described above because the recording operation can be further stabilized. Specific examples thereof include a capping unit for the recording head, a cleaning unit, a pressurizing or sucking unit, an electrothermal converter, a heating element different from this, or a preheating unit using a combination thereof. In addition, it is effective to provide a preliminary ejection mode for performing ejection different from recording in order to perform stable recording.
[0197]
Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrated or may be a combination of a plurality of colors. An apparatus having at least one of full colors can also be provided.
[0198]
In the embodiment described above, the description is made on the assumption that the ink is a liquid, but it may be an ink that is solidified at room temperature or lower, or an ink that is softened or liquefied at room temperature, Alternatively, the ink jet method generally controls the temperature of the ink so that the viscosity of the ink is within a stable discharge range by adjusting the temperature within a range of 30 ° C. or higher and 70 ° C. or lower. It is sufficient if the ink sometimes forms a liquid.
[0199]
In addition, it is solidified in a stand-by state in order to actively prevent temperature rise by heat energy as energy for changing the state of ink from the solid state to the liquid state, or to prevent ink evaporation. Ink that is liquefied by heating may be used. In any case, application of thermal energy such as an ink that liquefies by application of thermal energy according to a recording signal and liquid ink is ejected, or that already starts to solidify when reaching the recording medium. The present invention can also be applied to the case where ink having the property of being liquefied for the first time is used. In such a case, the ink is held as a liquid or solid in a porous sheet recess or through-hole as described in JP-A-54-56847 or JP-A-60-71260, It is good also as a form which opposes with respect to an electrothermal converter. In the present invention, the most effective one for each of the above-described inks is to execute the above-described film boiling method.
[0200]
In addition, as a form of the recording apparatus according to the present invention, a copying apparatus combined with a reader or the like, and a transmission / reception function are provided as an image output terminal of an information processing apparatus such as a computer or the like. It may take the form of a facsimile machine.
[0201]
Another object of the present invention is to supply a storage medium storing software program codes for implementing the functions of the above-described embodiments to a system or apparatus, and the computer (or CPU or MPU) of the system or apparatus stores the storage medium. Needless to say, this can also be achieved by reading and executing the program code stored in the.
[0202]
In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.
[0203]
As a storage medium for supplying the program code, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.
[0204]
Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) operating on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.
[0205]
Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.
[0206]
【The invention's effect】
It is possible to provide a recording method capable of high-quality recording while suppressing half-band unevenness and band unevenness, and a recording apparatus using the same.
[Brief description of the drawings]
FIG. 1A is a diagram for explaining a data distribution method in a recording apparatus according to an embodiment of the present invention.
FIG. 1B is a diagram showing a mask used in the output control unit 34 of the printing apparatus according to the embodiment of the present invention.
FIG. 2 is a diagram illustrating a division drive method of a recording apparatus as an embodiment of the invention.
FIG. 3 is a timing chart for explaining a division driving method in high-speed recording of the recording apparatus according to the embodiment of the invention.
FIG. 4 is a block diagram illustrating main components of the recording apparatus according to the embodiment of the invention.
FIG. 5 is a block diagram illustrating main components of an image processing unit of the recording apparatus according to the embodiment of the invention.
FIG. 6 is a schematic cross-sectional view of a main configuration of a recording apparatus as an embodiment of the present invention.
7A is a diagram illustrating an example of an arrangement of recording heads and a relationship between a recording paper feeding direction and a recording head scanning direction in the recording apparatus according to the embodiment of the invention. FIG.
FIG. 7B is a diagram illustrating the relative positional relationship of the recording head and the recording paper conveyance unit in the two-pass recording mode of the recording apparatus according to the embodiment of the invention.
FIG. 8 is a timing chart for explaining the SMS processing of the recording apparatus according to the embodiment of the invention.
FIG. 9 is a circuit diagram of an SMS processing unit of the recording apparatus according to the embodiment of the invention.
FIG. 10 is a timing chart for explaining image data distribution processing in the output control unit of the recording apparatus according to the embodiment of the invention.
FIG. 11 is a diagram illustrating an image data distribution circuit of the output control unit of the recording apparatus according to the embodiment of the invention.
FIG. 12 is a diagram illustrating a flow of image data in a two-pass recording mode of the recording apparatus as the embodiment of the invention.
FIG. 13A is a timing chart of the two-pass recording operation in the recording apparatus as the embodiment of the present invention, from the start of recording to the progress of four bands.
FIG. 13B is a timing chart of the two-pass recording operation in the recording apparatus according to the embodiment of the present invention until the end of recording after four bands.
FIG. 14A is a diagram showing a recording state in a 4-pass recording mode of the recording apparatus as the embodiment of the invention.
FIG. 14B is a diagram illustrating the flow of image data in the 4-pass recording mode of the recording apparatus as the embodiment of the invention.
FIG. 15A is a timing chart of the four-pass recording operation in the recording apparatus according to the embodiment of the present invention, from the start of recording to the progress of four bands.
FIG. 15B is a timing chart of the four-pass recording operation in the recording apparatus according to the embodiment of the present invention from the start of recording to the progress of four bands.
FIG. 15C is a timing chart of the 4-pass recording operation in the recording apparatus according to the embodiment of the present invention until the end of recording after four bands.
FIG. 15D is a timing chart of the four-pass recording operation in the recording apparatus according to the embodiment of the present invention until the end of recording after four bands.
FIG. 16 is a block diagram of a part of the internal configuration of the recording head used in the recording apparatus according to the embodiment of the invention.
FIG. 17 is a timing chart for explaining control of the recording head in the recording apparatus as the embodiment of the invention.
FIG. 18 is a timing chart illustrating divided driving of the recording head in the 2-pass mode or the 4-pass mode of the recording apparatus according to the embodiment of the invention.
FIG. 19 is a diagram illustrating an example of a printhead control circuit in the 2-pass mode or the 4-pass mode of the printing apparatus according to the embodiment of the invention.
FIG. 20 is a diagram illustrating an example of a printhead control circuit in the high-speed 4-pass mode of the printing apparatus according to the embodiment of the invention.
FIG. 21 is a block diagram of a part of the internal configuration of another recording head used in the recording apparatus according to the embodiment of the invention.
FIG. 22 is a diagram showing a recording state in a conventional recording apparatus.
FIG. 23 is a diagram illustrating another example of the arrangement of the recording heads in the recording apparatus according to the embodiment of the invention.
FIG. 24 is a diagram showing a conventional recording state when a recording head is arranged as shown in FIG.
FIG. 25 is a diagram showing a recording state in the recording apparatus as the embodiment of the invention when the recording head is arranged as shown in FIG.
[Explanation of symbols]
1 Host computer
2 Printer
3 CPU controller
4 Interface section
5 Control unit
6 Display / Operation section
8 Encoder section
11 Image processing unit
12 Front head unit
13 Back head unit
14 Carriage motor drive
15 Carriage motor
16 Transport motor drive
17 Conveyor motor
18 Carriage unit
19 Recording paper
20, 21 head drive
22, 23 Recording head
30 Image memory
31 Multi-value / Binary conversion part
32 SMS processing section
33 Cash register adjustment section
34 Output controller

Claims (7)

A first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements that perform recording of the same color as the first recording head are reciprocally scanned with respect to the recording medium, and a band is formed on the recording medium. A recording method for recording in units,
Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Generating first data for recording and second data for recording by the second recording head;
Dividing the first data into third data for outward recording and fourth data for backward recording according to a mask pattern;
Dividing the second data into fifth data for outward recording and sixth data for backward recording according to a mask pattern;
A first recording step for recording on the band on the basis of the third data while scanning the first recording head in the forward direction,
A second recording step for recording on the band based on said first recording head in the fourth data while scanning in the backward direction,
A third recording step for recording on the band based on the fifth data while scanning the second recording head in the forward direction ;
A fourth recording process for recording on the band based on the second recording head in the sixth data while scanning the in backward direction,
A conveying step of conveying the recording medium between the first and second recording steps and between the third and fourth recording steps;
A recording method in which a plurality rasters respectively in against, and said first through recording using four different recording elements in the fourth recording process is performed within the band.   2. The recording method according to claim 1, wherein the second recording head is located downstream of the first recording head in a conveyance direction of the recording medium. When the length of the first recording head and the second recording head D, and a width of the band and H, D = (2n + 1 ) × H / 2 (n is an integer) according to claim 2, characterized in that to satisfy the relation The recording method described in 1.   The recording method according to claim 1, wherein the second recording head is arranged to be separated from the first recording head in the scanning direction. A carriage in which a first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements that perform recording of the same color as the first recording head are arranged apart from each other in the scanning direction is provided with respect to a recording medium. A recording method for performing reciprocal scanning to record on the recording medium in band units,
Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Generating first data for recording and second data for recording by the second recording head;
Dividing the first data into third data for forward recording and fourth data for backward recording according to a first mask pattern;
Dividing the second data into fifth data for forward recording and sixth data for backward recording by a second mask pattern different from the first mask pattern;
While scanning the carriage in the outward direction, and performing recording on said third data and said fifth data each said band by driving the people said first and second recording heads each on the basis of,
While scanning the carriage to backward direction, and performing recording with respect to the fourth data and said sixth data respectively to said band by driving the people said first and second recording heads each on the basis,
A transport step of transporting the recording medium by a half bandwidth between the scan in the forward direction and the scan in the return direction;
For any raster in the band, the recording element of the first recording head used during the forward scan, the recording element of the second recording head used during the forward scan, and the first element used during the backward scan. 4. A recording method, wherein recording is performed using four different recording elements comprising a combination of recording elements of one recording head and recording elements of the second recording head used during the backward scanning. A first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements that perform recording of the same color as the first recording head are reciprocally scanned with respect to the recording medium, and a band is formed on the recording medium. A recording device for recording in units,
Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Means for generating first data for recording and second data for recording by the second recording head;
Means for dividing the first data into third data for outward recording and fourth data for backward recording according to a mask pattern;
Means for dividing the second data into fifth data for outward recording and sixth data for backward recording according to a mask pattern;
First recording operation for recording on said band said first recording head is scanned in the forward direction based on the third data, the first recording head is scanned in the backward direction on the basis of the fourth data third recording operation for recording on said second recording operation for recording on the band, the band said second recording head is scanned in the forward direction on the basis of the fifth data, the second means for executing a fourth recording operation of the recording head by scanning the in backward direction for recording on the band on the basis of the sixth data,
Conveying means for conveying the recording medium during the first and second recording operations and between the third and fourth recording operations;
Recording apparatus characterized by relative each of the plurality of rasters husband constituting the band dividing line recording using four different recording elements in said first to fourth recording operation. A carriage in which a first recording head having a plurality of recording elements and a second recording head having a plurality of recording elements that perform recording of the same color as the first recording head are arranged apart from each other in the scanning direction is provided with respect to a recording medium. A recording apparatus that performs reciprocal scanning to perform recording on the recording medium in band units,
Of the recording data and non-recording data constituting the image data corresponding to the band, the recording data is alternately distributed to the first recording head and the second recording head, thereby recording with the first recording head. Means for generating first data for recording and second data for recording by the second recording head;
Means for dividing the first data into third data for forward recording and fourth data for backward recording according to a first mask pattern;
Means for dividing the second data into fifth data for forward recording and sixth data for backward recording by a second mask pattern different from the first mask pattern;
The operation for recording on the band by driving the while scanning in the outward direction the third data and said fifth data respectively on the basis of the first and second recording heads each said carriage, said carriage return Means for driving each of the first and second recording heads based on the fourth data and the sixth data while performing scanning in a direction to perform recording on the band;
Conveying means for conveying the recording medium by a half band width between scanning in the forward direction and scanning in the backward direction,
For any raster in the band, the recording element of the first recording head used during the forward scan, the recording element of the second recording head used during the forward scan, and the first element used during the backward scan. recording element of one recording head, recording device recorded with four different recording element comprising a combination of the recording element of the second recording head used during the backward scan, characterized in that the dividing line.

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