JPH0970958A - Recording apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the total throughput and a recording grade by discriminating a blank region continuting over definite quantity or more and an actual recording region according to input image data to perform duty control in the actual recording region and scanning a recording head at a high speed in the blank region continuing over definite quantity or more. SOLUTION: The image data necessary for the recording of a recording head IJH is stored in the line buffer 103a of an RAM. The distribution of the image data performing the emission of ink is analyzed in a duty detection circuit 104 in relation to the image data stored in the line buffer 103a. On the basis of the analytical result, a CR driving part 107 is controlled so as to perform recording by changing the scanning speed of the recording head IJH within one scanning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording control method and a recording apparatus using the method, and more particularly, to a recording control method using a recording head according to an ink jet system and a recording apparatus using the method.

[0002]

2. Description of the Related Art Conventionally, there is an ink jet type recording apparatus for recording by ejecting ink to form an image. According to this recording method, a recording head in which a plurality of nozzles are arranged in a predetermined width in the conveying direction of the recording medium is scanned in a direction perpendicular to the nozzle row (hereinafter, this direction is referred to as a main scanning direction), On the other hand, the recording medium is conveyed in a direction perpendicular to the main scanning direction (hereinafter, this direction is referred to as the sub-scanning direction) to perform recording on the recording medium. In addition, in the recording by the recording head, generally, an electric current is applied to an electrothermal converter (heater) provided in the recording head, and the ink is boiled by the heat to eject the ink onto the recording medium. It was

In such an ink jet recording type recording apparatus, when the recording head is heated many times and the recording head is heated so that the ink cannot be ejected normally and the recording quality is deteriorated, for example, recording is performed. In a region of a predetermined width (hereinafter, this region is referred to as one line) in which a nozzle of a predetermined width of a head prints in one scan, ink is ejected from the print head with respect to the total number of recording pixels forming one line. The scanning speed of the print head for each line is controlled according to the ratio of the number of pixels for printing (hereinafter, this ratio is referred to as the duty ratio). Further, one line is equally divided into a plurality of areas in the main scanning direction, and when the duty ratio of any of the divided areas is equal to or greater than a predetermined threshold value, the scanning speed of the print head in that line is controlled.

[0004]

However, the recording control in the above-mentioned conventional recording apparatus has the following problems because the scanning speed of the recording head is controlled for each line and is constant within that line. There was a point. When recording control of the recording head is performed based on the duty ratio of each line, the distribution of the image data recorded on each line is not uniform in many lines and often includes many blank areas. In this case, the recording control based on the duty ratio of each line cannot control the region included in the line having a locally high or low duty ratio. Therefore, even in a region where the duty ratio is locally high included in the line, the scanning speed of the print head is controlled by the average duty ratio calculated for each line. Therefore, the scanning speed should be slowed down originally. However, there is a problem that printing is performed at a speed higher than the desired scanning speed, resulting in deterioration of printing quality.

On the other hand, when one line is equally divided into a plurality of areas and the recording control of the recording head is performed based on the duty ratio of any of the divided areas, conventionally, the line is divided into a plurality of areas at a predetermined place. Areas where ink is ejected from the print head that changes dynamically according to the image data because it is only divided (hereinafter, this area is called the actual print area)
The control that reflects the duty ratio is not performed, and there is a problem that the print quality is degraded as in the case described above.

Further, even if there is a blank area in a plurality of divided areas included in one line,
Since the scanning speed of the recording head is determined based on the duty ratio of one of the divided areas, even if it is originally desired to increase the scanning speed, recording is performed at a speed slower than the desired scanning speed. As a result, there is a problem that the total throughput is reduced.

The present invention has been made in view of the above problems, and discriminates a blank area and an actual recording area that continue for a certain amount or more according to input image data, performs duty control in the actual recording area, and continues for a certain amount or more. It is an object of the present invention to provide a recording apparatus capable of improving the total throughput and the recording quality by scanning the recording head at high speed in the blank area.

[0008]

The recording apparatus according to the present invention for achieving the above object has the following arrangement. That is, a recording device having recording means for performing recording by ejecting ink from a recording head onto a recording medium, the storage means storing image data necessary for recording by at least one scan of the recording head, and the storage means. With respect to the image data stored in, the analyzing unit that analyzes the distribution of the image data that causes ink to be ejected, and the scanning speed of the recording head is changed within one scan based on the analysis result by the analyzing unit, and recording is performed. And a control means for controlling the recording means.

A recording method according to the present invention for achieving the above object has the following configuration. That is, a recording method including a recording step of ejecting ink from a recording head onto a recording medium to perform recording, and a storage step of storing image data necessary for recording by at least one scan of the recording head, and the storage step. With respect to the image data stored in the storage medium, the analysis step of analyzing the distribution of the image data for ejecting ink, and the scanning speed of the recording head is changed within one scan based on the analysis result of the analysis step. And a control step of controlling the recording step so as to perform recording.

[0010]

With the above arrangement, the present invention provides an image required for recording by at least one scan of the recording head in a recording apparatus having recording means for ejecting ink from the recording head onto a recording medium for recording. Store the data in a storage medium. Then, with respect to the image data stored in the storage medium, the distribution of the image data for ejecting ink is analyzed. Based on the analysis result, set the scanning speed of the recording head to 1
The recording means is controlled so that the recording is performed while changing the scanning.

Here, the printing apparatus has a first area in which image data for which ink ejection is not performed in a single scan of the print head continues for a predetermined amount or more, image data for which ink ejection is performed, and image data for which ink ejection is not performed. The second area to be mixed is discriminated. The printing apparatus also calculates a duty ratio for the second area and compares the calculated duty ratio with a predetermined threshold. Then, the scanning speed of the recording head in the second area is controlled according to the comparison result.

Further, the printing apparatus sets the scan speed of the print head to a speed lower than the predetermined speed when the duty ratio is larger than the predetermined threshold value, and the scan speed of the print head when the duty ratio is smaller than the predetermined threshold value. The control is performed so that the speed is a predetermined speed. Furthermore, the recording device relates to the first area,
The recording unit is controlled so that the scanning speed of the recording head is higher than a predetermined speed to perform recording.

The above-mentioned recording head may be of a type such as an ink jet recording head which ejects ink to perform recording, or a type which ejects ink by utilizing thermal energy. It may be provided with a thermal energy converter for generating thermal energy. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an external perspective view showing the outline of the configuration of an ink jet printer IJRA which is a typical embodiment of the present invention. In FIG. 1, the spiral groove 50 of the lead screw 5005 that rotates via the driving force transmission gears 5009 to 5011 in conjunction with the forward / reverse rotation of the drive motor 5013.
The carriage HC that engages with the pin 04 is a pin (not shown).
And is supported by the guide rail 5003 and is indicated by arrows a and b.
Reciprocate in the direction. On the carriage HC, an integrated type ink jet cartridge IJC containing a recording head IJH and an ink tank IT is mounted. 5002
Denotes a paper pressing plate, which presses the recording paper P against the platen 5000 in the moving direction of the carriage HC. 50
Reference numerals 07 and 5008 denote photocouplers, which confirm the presence of the lever 5006 of the carriage HC in this area, and
13 is a home position detector for switching the rotation direction of 13 and the like. When the recording paper P is conveyed, the rotation of the motor 5013 is transmitted to the platen 5000 via the transmission gear 5010, and the rotation of the platen 5000 conveys the recording paper P in a direction substantially orthogonal to the moving direction of the carriage HC. Reference numeral 5016 is a member that supports a cap member 5022 that caps the front surface of the recording head IJH. Reference numeral 5015 is a suction device that sucks the inside of the cap, which is an opening 50 in the cap.
The suction recovery of the recording head is performed via 23. 5017 is a cleaning blade, and 5019 is this blade 50.
It is a member that allows 17 to move in the front-rear direction, and these are supported by a main body support plate 5018. Blade 501
Needless to say, the known cleaning blade 7 is not limited to this type and can be applied to the present example. Also, 5021
Is a lever for starting the suction for suction recovery, which moves in accordance with the movement of the cam 5020 engaging with the carriage HC, and the driving force from the driving motor is movement-controlled by a known transmission mechanism such as clutch switching. .

The capping, cleaning, and suction recovery are configured so that the desired processing can be performed at their corresponding positions by the action of the lead screw 5005 when the carriage HC comes to the area on the home position side. Any desired operation can be applied to this example if desired operation is performed at the timing. The inkjet printer IJRA according to the present embodiment can record at a recording density of 360 dpi. In addition, the recording head IJH is
It is assumed that the inkjet printer IJRA has 64 nozzles in the conveyance direction (sub-scanning direction) of the recording paper P and has a resolution of 360 dpi. Further, it is assumed that one nozzle of the printhead IJH corresponds to image data represented by one pixel and one bit. Furthermore, the recording head IJH
Is opposed to the recording paper P and is reciprocated in the direction (main scanning direction) perpendicular to the conveyance direction of the recording paper to perform recording. At this time, the recording length that the recording head IJH records in the main scanning direction is L.

Next, a control configuration for executing the recording control of the above-mentioned apparatus will be described. FIG. 2 is a block diagram showing the configuration of the control circuit of the inkjet printer IJRA of this embodiment. In FIG. 2, 101 is a CPU
And executes the operation control and data processing of this device. A ROM 102 stores a control program of the CPU 101 and font data for font processing. The ROM 102 also stores a program for performing duty control, which will be described later, and a threshold value for determining whether to perform duty control. Further, a plurality of predetermined threshold values for deciding whether or not the print head IJH is scanned at a high speed in an area where ink is not ejected (blank area) is stored.

A RAM 103 temporarily stores various data. The RAM 103 also has a recording head IJH.
One scan recorded by one scan (64 dots x L
Line buffer 1 for storing (scan width) image data
03a and a CR position buffer 103b that stores information for determining whether or not the image data is data that requires ink ejection in units of 12 dots in the scanning direction of the printhead IJH. Hereinafter, the recording head IJ
An area printed by H scanning is called one line.

FIG. 3 is a diagram showing the internal structure of the line buffer 103a and the CR position buffer 103b. FIG.
As shown in, the line buffer 103a is an area capable of storing image data required for recording one line, and the buffer logically has a capacity of 64 dots × L.

The CR position buffer 103b has 64 dots (sub-scanning direction) × 12 of the line buffer 103a.
The configuration is such that 1-bit information corresponding to each dot (main scanning direction) area can be stored (b1, b2, ..., Bn (= L / 12)), and the capacity is L / 12 bits. Now,
If the line buffer 103a is defined as a normal area in the RAM 103 and each data bit is stored in ascending order from the address A0 as shown by the arrow in FIG. 3, the storage address of each data bit is A0 + n (n = 0. , ..., 64 × L-1). On the other hand, each bit of the CR position buffer 103b has 64 dots of the line buffer 103a x
“0” or “1” is set according to the value of the image data stored in the 12-dot area. That is, if all the image data bits in the area are “0”, the corresponding bit is set to “0”, and if the area has one image data bit having a value of “1”, the corresponding bit is set to the corresponding bit. Sets "1".

The value of the CR position buffer 103b is initialized so that all the bits are always "0" before processing the data for one line. Although details will be described later, the CPU 101 controls the scanning speed of the carriage HC according to the bit pattern set in the CR position buffer 103b. A data receiving unit 100 controls communication with an external device (not shown) such as a host computer and captures image data sent from the external device.

Reference numeral 105 denotes a head drive unit, which controls the CPU 101 for recording an image on a recording medium, transfers a transfer of image data to a head driver (not shown) and generates a heat pulse signal, and a recording head. It is composed of a head driver (not shown) that drives the IJH. Reference numeral 106 denotes an LF drive unit 106, which includes a paper feed motor driver 106a and a paper feed motor 106b, and is a control system that conveys a recording medium such as the recording paper P according to a control signal supplied from the CPU 101.

Reference numeral 107 denotes a CR drive unit 107, which includes a carriage motor driver 107a and a carriage motor 107.
b and carriage position detection circuit 107c, and C
A control system that moves the printhead IJH in response to a control signal supplied from the PU 101. Reference numeral 104 denotes a duty detection circuit, which controls 6 lines per line in order to control the speed of the carriage HC driven by the CR drive unit 107.
It is divided into 4 × 12 bit unit areas, and the presence or absence of image data is determined in each of the unit areas.

The CPU 101 controls the scanning speed of the recording head IJH based on the result of the determination. That is,
If the result of determination is that there is image data that requires ink ejection for even one pixel in the unit area, the duty ratio in that area is calculated, and unit areas in which the calculated duty ratio is greater than or equal to a predetermined threshold value are continuous to some extent. The control is performed so that the scanning speed of the recording head IJH is moved slower than a predetermined scanning speed in the continuous area. On the other hand, if an area that does not have image data that requires ink ejection is continuous to some extent, control is performed so that the scanning speed of the print head IJH is faster than a predetermined scanning speed in the continuous area.

Next, an outline of recording control will be described with reference to FIG. First, the data input from the host computer by the data receiving unit 100 is temporarily stored in the line buffer 103a of the RAM 103. And CPU
101 executes the control program stored in the ROM 102 to analyze the received command, image data, character code, etc. stored in the line buffer 103a. In case of character code, RO corresponding to that character code
The font data stored in advance in M102 is read out, and the read-out font data is sequentially stored in the RAM 10
3 to the line buffer 103a.

The carriage motor 107b is driven by the carriage motor driver 107a incorporated in the CR drive unit 106 when the image data for one line is expanded in the line buffer 103a or when a recording command is input from the host computer. Then, while moving the carriage HC, the image data stored in the line buffer 103a in synchronization with the recording timing pulse output from the carriage position detection circuit 107c is transferred to the head through the head controller built in the head drive unit 105. The print head IJH is transmitted to the driver, and a heat pulse signal is sent from the head controller to the head driver.
Ink is ejected from the device to perform recording.

When the recording for one line is completed, the paper feed motor driver 106a incorporated in the LF drive unit 106 drives the paper feed motor 106b to perform a line feed, and the series of procedures is completed. By repeating such a procedure for one page of the recording paper P, the recording operation for one page is completed. FIG. 4 is a block diagram showing a detailed configuration of the duty detection circuit.

In the circuit of this embodiment, the line buffer 1
The image data stored in 03a is read every 2 bytes by DMA transfer, and it is checked whether or not all the bit values are "0" for each read 2 bytes of image data. With respect to the unit area including the value, the duty ratio is obtained. In FIG.
When the image data received from the data receiving unit 100 is expanded by one line in the line buffer 103a or a recording command is input from the host computer, C
The PU 101 is the start address A of the line buffer 103a.
0 and the number of transfer bytes (here, 2 bytes) are set in the DMA address setting unit 202.

Next, the address A0 set by the DMA address setting unit 202 and the number of transfer bytes (2 bytes) are D
It is set in the MA address updating unit 203. And D
Address A0 set in MA address updating unit 203
According to the number of transfer bytes (2 bytes), the line buffer address transfer unit 205 outputs the address A0 together with the read signal to the line buffer 103a. As a result, 16-bit (2-byte) image data having the address A0 as the start address is read in parallel from the line buffer 103a and input to the NULL data detection unit 207.

The NULL data detector 207 determines whether or not all the bits of the input 2-byte image data are "0". Here, when all the bits of the image data are “0”, the NULL data detecting unit 207 notifies the NULL data counting unit 209 of that fact, and the NULL data counting unit 209 then outputs “0”.
The number of bits is counted (here, "16"). Then, the count value is the white dot counting unit 2
It is output to 10.

If all of the input 2-byte image data are not "0", the NULL data detection unit 207 is executed.
Is the CR pointed to by the CR position buffer address pointer 204
"1" is output to the address bit of the position buffer 103b, the image data is transferred in parallel to the data shift unit 208, and the transferred image data is shifted bit by bit, and each bit is a white dot. It is determined whether or not (bit value is “0”), and the number of white dots is counted. When the shift and determination of the 16-bit image data are completed, the counted number of white dots is output to the white dot counting unit 210. Therefore, in the white dot count unit 210, whether the output from the data shift unit 208 or the output from the NULL data count unit 209, the value of the bit in the input 2-byte image data is "0". The number of bits, that is, the number of white bits will be obtained.

After the count is completed, the address set in the DMA address communication unit 203 is incremented by 16 by the DMA transfer address setting unit 203, and 2 bytes of image data is updated from the updated address pointer.
It is read from 3a. Next, the same processing as described above is performed on the newly input 2-byte image data. Then, the white dot count unit 210 adds and accumulates the number of white dots included in the newly input 2-byte image data and the number of white dots obtained previously. Below, FIG.
The image data stored in the line buffer 103a is read in 2-byte units by DMA transfer along the arrow indicated by, and a 2-byte unit is read for the image data included in the unit area stored in the line buffer 103a. Then, it is judged whether or not all the bits are "0".

When the above processing is completed, white dots 210
, The number of white dots of the image data included in the unit area is accumulated. The number of white dots obtained in this way is output to the duty ratio setting unit 212. The value accumulated in the white dot counting unit 210 is reset for each unit area. The NULL data detection unit 207 monitors the number of times of transfer of the input image data, and outputs a count signal to the counter 206 every time the image data is input from the line buffer 103a in 2-byte units by DMA transfer. Also, the number of output count signals is monitored, and when the number of times reaches 48, the clear signal is sent to the counter 206.
To clear the counter value to zero.

The counter 206 counts the number of count signals input from the NULL data detection unit 207, and outputs an increment signal to the CR position buffer address pointer 204 every time the count value reaches 48. When the increment signal is output, the clear signal is input from the NULL data detection unit 207 and the contents of the counter are cleared.

Further, the CR position buffer address pointer 204 is a pointer that points to an address for accessing the CR position buffer 103b, and points to bit b0 in the initial state. Then, every time an increment signal is input from the counter 206, the CR position buffer 103b pointed to by the pointer is incremented by +1 and the address can be accessed.

By the above-described operation, all bits of the image data included in one unit area are checked, and if even one bit of data "1" is included in the unit area, the CR
Corresponding bits bi of the position buffer 103b (i = 1, ...,
n) is set to "1", while if all the bits of the unit area are "0", the corresponding bit bi (i = 1, ..., N) of the CR position buffer 103b becomes "0".

When the above processing for one line of image data is executed for all unit areas, the distribution of white dots of the image data for each unit area in each bit b0, b1, ..., Bn of the CR position buffer 103b. Will be set. Then, the duty ratio calculation unit 21
In accordance with the contents of the CR position buffer 103b, 2 calculates the duty ratio of the unit area including the bit that requires ink ejection, and outputs the result to the CPU 101.

Next, regarding the processing flow of this embodiment,
This will be described with reference to the flowcharts of FIGS. The flowchart shown below describes the processing of the present embodiment for one line of image data stored in the line buffer 103a, and this processing is performed for each line of image data for one page of the recording paper P. The processing for one page is completed by repeatedly performing the processing over.

In step S700, the line buffer 10
When the image data for one line is stored in 3a, in step S701, the image data is extracted from the line buffer 103a by 2 bytes in accordance with the arrow shown in FIG. 3, and whether or not the data includes the number of white dots is determined. The number of white dots of the image data for the unit area is counted while checking.

In step S702, it is determined whether all the image data bits in the unit area are "0". If all the bits of the image data in the unit area are “0”, the process proceeds to step S705. On the other hand, if the bit of the image data in the unit area includes "1", the process proceeds to step S704, and "1" is set to the bit of the carriage position buffer 103b corresponding to the unit area for which the determination is made.

In step S705, it is checked whether or not the determination has been completed for all the unit areas forming one line of image data. Here, if it is determined that the determination is completed, the process proceeds to step S706. On the other hand, if the determination is not completed, the process returns to step S701, and the processes of steps S701 to S705 are repeated until the determination is completed.

In step S706, the bit pattern of "0" or "1" written in each bit b0, b1, ..., Bn of the CR position buffer 103b is analyzed. In step S707, based on the analysis result, it is checked whether there is a place where the bit value "0" continues.
The threshold value (TH) is a constant speed (high speed) region in which the printhead IJH performs an acceleration operation necessary for increasing the scan speed from a predetermined scan speed (VN) or a scan speed controlled by duty control to a constant high speed. ), And the minimum necessary length that must be ensured as a deceleration operation area necessary to return to the predetermined scanning speed or the scanning speed controlled by the duty control again. .

Here, one line is divided into the continuous area and the non-continuous area as described above, and the area where "0" continues for TH or more is not ejected and the recording head IJH is driven at a high scanning speed. The area to be moved (skip area) is defined as the actual recording area. Then, in a succeeding step S708, a duty ratio is obtained for the divided actual recording area. This calculation is performed based on the duty ratio obtained for each unit area.

Above, steps S706 to S70
An example of the results obtained in No. 8 is shown in FIG. FIG. 7 is an example in which one line is divided into three areas, that is, one skip area and two actual recording areas based on the bit pattern set in the CR position buffer 103b. And 2
The duty ratio is calculated for each of the two actual recording areas.

Next, after such preparations, step S7
At 09, scanning is started and the recording head IJH is moved. Then, first, in step S710, it is checked whether or not the area to be scanned is a skip area. Here, if it is determined to be the skip area, the process proceeds to step S711, and if it is determined to be the actual recording area, the process proceeds to step S712. Step S711
Then, the scanning speed of the recording head IJH is made to scan at a speed (VH) higher than a predetermined scanning speed (VN). Thereafter, the processing proceeds to step S715.

Now, in the process, in step S712, it is checked whether or not the duty ratio of the actual recording area is larger than a predetermined threshold value (DTH). Where duty ratio (D) and DTH
If D> DTH, the process proceeds to step S713, and the scanning speed of the recording head IJH for recording the actual recording area is scanned at a constant speed (VL) slower than a predetermined scanning dynamic speed (VN). To control. If D ≦ DTH, the process advances to step S714 to control the actual print area to scan the printhead IJH at a predetermined scan speed (VN). Then, the process is step S715.
At, it is checked whether or not the scanning by the print head IJH is completed. If the scanning is continued, the process returns to step S710, and if completed, the process is terminated.

Through the above-described processing, the CPU 101 performs speed control of acceleration, constant speed, and deceleration of the recording head IJH according to the duty ratio of each actual recording area. As an example, FIG.
A recording operation of the recording head IJH when the actual recording area 1, the skip area, and the actual recording area 2 are obtained as shown in FIG. In this case, assuming that the duty ratio of the actual recording area 2 is D> DTH and the duty ratio (D) of the actual recording area 1 is D ≦ DTH, the recording head IJH in the actual recording area 2 has a predetermined scanning speed ( It is controlled to move at a constant speed (VL) slower than VN).

As shown in the figure, the recording head IJH
Secures a region for accelerating the recording head IJH as shown in region A so that it can move at a constant speed from the recording start position. In addition, the recording head IJH as shown in the area G so that the recording head IJH can be stopped from the recording end position.
An area for decelerating JH is secured. In FIG. 7, since the print start position is the actual print area, the scan speed of the print head IJH is accelerated and controlled in the area A from the area B so that the scan speed of the print head IJH can be scanned at the predetermined scan speed (VN). Scan at speed VN.

Next, when the print head IJH enters the skip area, the print head IJH is accelerated and controlled in the area C so that the print head IJH can be scanned at a high speed (VH), and the speed is changed from the area D to the speed VH.
To move. Also, from the area F to a predetermined scanning speed (VN)
In order to scan at a slower speed (VL), a region E for deceleration control is secured in order to decelerate the scanning speed in the skip region.

When the recording head IJH is decelerated in the area E, the recording head IJH scans the actual recording area 2 from the area F to the recording end position at the speed VL. Then, the deceleration control is performed in the region G, and the scanning of the recording head IJH is stopped, whereby the recording process for one line is completed. This process is performed by the line buffer 103.
The recording operation for one page of the recording paper P is completed by performing this operation every time the image data is stored in the entire storage area a.

In this embodiment, one threshold value is used to control the scanning speed of the actual recording area, but the present invention is not limited to this. For example, by changing the scanning speed of the recording head IJH within one line according to the duty ratio for each actual recording area for recording, it is possible to further improve the recording quality and the total throughput. .

Further, the judgment as to whether or not it is the skip area is performed using one threshold value, but the present invention is not limited to this. For example, as shown in FIG. 8, a plurality of conditions are provided, the number of times that the bit “0” continues for TH or more in the CR position buffer 103b is determined using a plurality of thresholds, and the scanning speed Y of the print head IJH is set to Y = VH. , KV
H, 2kVH, ..., nkVH (k> 1), 1
It is also possible to perform control by changing the scanning speed of the recording head IJH within the line to perform recording. As a result, the total throughput can be further improved.

In the region below the threshold value TH, VL is always
It may be configured to scan with. Further, the configuration may be such that a plurality of threshold values TH are used without performing duty control and scanning is performed at a speed corresponding to each threshold value. As described above, according to the present embodiment, the image data stored in the line buffer 103a is investigated and divided into fine areas, and the actual recording area and the skip area are determined based on the data distribution in the divided areas. Is determined, and the scanning speed of the recording head IJH within one line is changed according to the determination result to perform recording, thereby improving the total throughput and maintaining high quality recording quality. That is, since the scanning speed of the print head IJH is controlled in units of finely divided areas, printing can be performed at an optimum scanning speed due to the duty ratio of the actual printing area that dynamically changes in one line, and the printing quality can be improved. Can be improved. Further, in the skip area, it is possible to record at a high scanning speed at the same time, so that the total throughput can be improved.

In the present embodiment, particularly in the ink jet recording system, a means (for example, an electrothermal converter or a laser beam) for generating heat energy as energy used for ejecting ink is provided, and If you use a method that causes a change in ink status with energy,
Higher recording density and higher definition can be achieved. For the representative configuration and principle, see, for example, US Pat.
It is preferable to use the basic principle disclosed in Japanese Patent No. 29,4740796. This method can be applied to both the so-called on-demand type and the 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). Applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding film boiling to the electrothermal transducer, thereby causing the electrothermal transducer to generate thermal energy, and This is effective because it causes film boiling on the heat-acting surface, and as a result, bubbles in the liquid (ink) corresponding to this drive signal on a one-to-one basis can be formed. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of the liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed. As a configuration of the recording head, in addition to the combination of the ejection port, the liquid path, and the electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, a heat acting surface A configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which a is bent, is also included in the present invention. In addition, Japanese Patent Laid-Open Publication No. Sho 5 discloses a configuration in which a common slot is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters.
Japanese Unexamined Patent Publication No. 9-123670 discloses a structure in which an opening for absorbing a pressure wave of thermal energy corresponds to a discharge portion.
A configuration based on JP-A-9-138461 may be adopted.

Further, as a full line type recording head having a length corresponding to the maximum width of the recording medium which can be recorded by the recording apparatus, the length can be increased by combining a plurality of recording heads as disclosed in the above-mentioned specification. Either of the structure satisfying the requirement or the structure as one recording head integrally formed may be used. In addition, the ink is integrated into the replaceable chip-type recording head, or the recording head itself, which can be electrically connected to the apparatus main body and can supply ink from the apparatus main body by being attached to the apparatus main body. A cartridge-type recording head provided with a tank may be used.

Further, in order to further stabilize the recording operation of the recording head provided as the structure of the recording apparatus of this embodiment, it is preferable to add a preliminary auxiliary means or the like. Specific examples thereof include a means for pressurizing or suctioning the recording head, a preheating means using an electrothermal converter, a separate heating element or a combination thereof. It is also effective to provide a preliminary ejection mode in which ejection is performed separately from printing, in order to perform stable printing.

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 integrally formed or a plurality of combinations may be used. Alternatively, the device may be provided with at least one of full-color mixed colors. As described above, the present embodiment has been described on the assumption that the ink is a liquid. However, even if the ink solidifies at room temperature or lower, an ink that softens or liquefies at room temperature is used. Or, in the inkjet method, generally, the temperature of the ink itself is adjusted within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. It is sufficient that the ink is in a liquid state when the use recording signal is applied.

In addition, in order to positively prevent the temperature rise due to thermal energy from being used as energy for changing the state of the ink from the solid state to the liquid state,
Alternatively, in order to prevent evaporation of the ink, an ink which solidifies in a standing state and liquefies by heating may be used. In any case, by applying thermal energy such as ink that is liquefied by applying thermal energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In such a case, as described in JP-A-54-56847 or JP-A-60-71260, the ink is held in a liquid state or a solid state in the concave portion or through hole of the porous sheet. It is good also as a form which opposes an electrothermal transducer. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method. In addition, as a form of the recording apparatus according to the present invention, in addition to a recording apparatus integrally or separately provided as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a transmission / reception function are provided. It may be in the form of a facsimile machine.

The present invention may be applied to a system composed of a plurality of devices such as a host computer and an interface, or may be applied to an apparatus composed of a single device such as a copying machine. Needless to say, the present invention can be applied to a case where the present invention is implemented by supplying a program to a system or an apparatus. In this case, the storage medium storing the program according to the present invention constitutes the present invention. Then, by reading the program from the storage medium to the system or device, the system or device operates in a predetermined manner.

[0060]

As described above, according to the present invention,
With respect to the image data for one scan, the distribution of the image data for ejecting ink is analyzed, and the scanning speed of the print head is changed within one scan to perform printing according to the result, thus improving the total throughput. There is an effect that high quality recording quality can be maintained.

[Brief description of drawings]

FIG. 1 is an external perspective view showing an outline of a configuration of an ink jet printer IJRA which is a typical embodiment of the present invention.

FIG. 2 is an inkjet printer IJR of the present embodiment.
3 is a block diagram showing a configuration of an A control circuit. FIG.

FIG. 3 is a line buffer 103a and a CR according to the present embodiment.
It is a figure which shows the relationship of the address of the position buffer 103b.

FIG. 4 is a block diagram showing a detailed configuration of a duty detection circuit according to the present embodiment.

FIG. 5 is a flowchart showing a processing flow of the present embodiment.

FIG. 6 is a flowchart showing a processing flow of the present embodiment.

FIG. 7 is a diagram showing a recording operation of the recording head IJH according to the present embodiment, a relationship between a write signal written in the CR position buffer 103b, and a line buffer 103a.

FIG. 8 is a diagram showing a relationship between a skip region and a scanning speed according to the present embodiment.

[Explanation of symbols]

 100 data receiving unit 101 CPU 102 ROM 103 RAM 103a line buffer 103b CR position buffer 104 duty detection circuit 105 head drive unit 106 LF drive unit 106a paper feed motor driver 106b paper feed motor 107 CR drive unit 107a carriage motor driver 107b carriage motor 107c Carriage position detection circuit IJH recording head 202 DMA address setting unit 203 DMA address updating unit 204 CR position buffer address pointer 205 line buffer address transfer unit 206 counter 207 NULL data detection unit 208 data shift unit 209 NULL data counting unit 210 white dot counting unit 212 Duty Ratio Calculation Unit

Claims (9)

[Claims] 1. A recording apparatus having recording means for recording by ejecting ink from a recording head onto a recording medium, the storage means storing image data necessary for recording by at least one scan of the recording head, With respect to the image data stored in the storage unit, an analyzing unit that analyzes the distribution of image data that causes ink to be ejected, and the scanning speed of the recording head is changed within one scan based on the analysis result by the analyzing unit. And a control unit that controls the recording unit so as to perform recording. 2. A first area in which image data for which ink is not ejected continues for a predetermined amount or more in one scan of the recording head, image data for which ink is ejected, and image data for which ink is not ejected, 2. The recording apparatus according to claim 1, further comprising a determining unit that determines a second area in which is mixed. 3. The comparison means includes a calculation means for calculating a duty ratio for the second region and a comparison means for comparing the duty ratio calculated by the calculation means with a predetermined threshold value. The recording apparatus according to claim 2, wherein the scanning speed of the recording head in the second area is controlled according to the comparison result according to. 4. The control means, when the duty ratio is larger than the predetermined threshold value, makes the scanning speed of the recording head slower than a predetermined speed, and when the duty ratio is smaller than the predetermined threshold value, The recording apparatus according to claim 3, wherein the scanning speed of the recording head is controlled to be the predetermined speed. 5. The control unit controls the recording unit to perform recording by scanning the scanning speed of the recording head at a speed higher than the predetermined speed with respect to the first area. Item 2. The recording device according to item 2. 6. The control unit controls the recording unit to perform recording by gradually changing the scanning speed of the recording head according to the length of the first area. Item 2. The recording device according to item 2. 7. The recording apparatus according to claim 1, wherein the recording head is an inkjet recording head that performs recording by discharging ink. 8. The recording head is a recording head for ejecting ink by utilizing thermal energy, and is provided with a thermal energy converter for generating thermal energy applied to the ink. The recording device according to item 1. 9. A recording method comprising a recording step of ejecting ink from a recording head onto a recording medium to perform recording, and a storage step of storing image data necessary for recording by at least one scan of the recording head, With respect to the image data stored in the storage medium in the storage step, an analysis step of analyzing a distribution of image data for ejecting ink, and a scanning speed of the recording head for one scan based on the analysis result of the analysis step. And a control step for controlling the recording step so that the recording is performed while changing the recording method in the recording method.