JP2002301815A - Recorder and method of creating recording data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deterioration in recording quality in a recorded image, particularly in a highlighted portion or an intermediate gradation portion when the recording is performed by forming plural sizes of dots. SOLUTION: Data C, SC for ejecting large and small ink drops of a cyan ink is independently subjected to processing for digitizing it into n values. The data C in relation to the large drop is placed on a portion (portion greater than 128) corresponding to a highlighted portion or an intermediate gradation portion in an image in the recording data, and then a large dot is formed in this region in the recording so that it is possible to make a white line due to shift of the arrival position of a small dot inconspicuous.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus and a printing data creation method, and more particularly, to a printing apparatus for printing by expressing a gradation level by a combination of printing dots of different sizes, and a printing apparatus using such printing apparatus. It relates to creation of recording data to be used.

[0002]

2. Description of the Related Art As a typical example of such a device,
2. Description of the Related Art An ink jet recording apparatus that records an image by applying the same color ink at a plurality of different ejection amounts is known. The recording data used in this apparatus is multi-valued for each pixel (for example,
This is obtained by finally converting the image data in which the gradation is expressed in the form of 8-bit 0 to 255) into binary ejection data. For example, based on the value indicated by the image data, the image data is converted into a plurality of bits of pattern data representing several levels of gradation, and an index indicating a predetermined dot arrangement relationship for the level represented by the pattern data. Based on the pattern, binary ejection data for forming dots of the pattern is obtained.
By appropriately determining the index pattern, it is possible to set the gradation and the maximum density of an image to be printed.

For example, image data of 256 gradations from 0 to 255 is converted into 4 bits (4 bits) representing 9 values (levels 0 to 8).
In the configuration in which the data is converted into binary data by an index pattern corresponding to the pattern data, the arrangement of large and small dots is determined for each of the nine levels. Things. Thus, the multi-valued image data is converted into ejection data (binary data) of each nozzle corresponding to the size of the ink droplet ejected by the recording head.

[0004] Such an index pattern is one of the factors that determine the characteristics of a recorded image such as gradation,
Generally, when a relatively large amount of ink is used in a highlight portion of an image, for example, the graininess increases, for example,
Of the nine levels, up to the level corresponding to the intermediate gradation area, a pattern with only small dots is set, and a pattern in which large dots start to be arranged at a higher gradation value level.

[0005]

However, in the index pattern, the arrangement of large and small dots is uniformly determined among these dots in accordance with the pattern data.
As described above, since the range of the gradation value that can be represented by the image data is uniformly allocated to each level,
At a level corresponding to a small gradation value, only small dots tend to be arranged.

As a result, the following problem may occur in a highlight portion of an image or an intermediate gradation portion having a higher density than that expressed at a level where only such small dots are arranged. Since a relatively small amount of ink (small droplet) forming a small dot has relatively small kinetic energy due to ejection, the vibration of the mechanical part accompanying the recording operation and the movement of the recording head In some cases, the ejection state may be disturbed (distorted) due to the influence of the airflow that occurs, and the positions of the formed dots may be shifted. This will be recognized as a deterioration in the quality of the recorded image. In particular, the dot density is higher in the intermediate gradation portion than in the highlight portion, and streaks and the like become more noticeable due to the shift of the dot formation position.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a method for forming an image recorded by forming dots of a plurality of sizes.
In particular, it is an object of the present invention to provide a recording apparatus and a recording data creation method that can reduce a decrease in recording quality in a highlight portion or an intermediate gradation portion.

[0008]

For this purpose, the present invention provides a recording apparatus for recording on a recording medium using a recording head provided with recording elements having different sizes of dots to be formed. Data generation means for generating print data corresponding to each of the printing elements having different sizes of dots under predetermined conditions, and the print data generated by the data generation means by arranging dots in each pixel. Means for converting to dot data to be formed, wherein the conversion means performs a process of independently converting each of the dots having a different size.

[0009] Also, there is provided a method for creating print data used in a printing apparatus for printing on a print medium using a print head provided with print elements having different sizes of dots to be formed,
Recording data corresponding to each of the recording elements having different sizes of dots to be formed of the recording head is generated under predetermined conditions, and the recording data generated by the data generating means is formed by arranging dots in each pixel. Means for converting the data into dot data for converting each dot having a different size independently from each other.

According to the above arrangement, the print data corresponding to each of the print elements having different sizes of dots to be formed in the print head is converted into a predetermined data such that the total gradation change by these dots is linear. Therefore, when converting the generated print data into dot data for forming dots having different sizes in one pixel, the size of the generated print data is not taken into account in consideration of the predetermined condition. The conversion can be performed for each of a plurality of dots having different sizes. Thereby, the conversion process can be arbitrarily set for each dot under the above-mentioned predetermined condition.

In addition, by arranging larger dots in the density expression not more than the intermediate value of the density value width that can be expressed by dot formation, it is possible to mix larger dots and smaller dots with the density not more than the intermediate value. it can.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 3 are schematic views showing three examples of an arrangement of discharge ports in a recording head which can be used in an ink jet recording apparatus according to an embodiment of the present invention. As shown in these figures, among the cyan (C), magenta (M), and yellow (Y) inks, respective nozzles (ejection ports) that eject different amounts (volumes) of ink droplets for a predetermined color ink ) Are provided on the same head chip or different head chips. In addition, black (K)
No nozzle is provided so as to eject such different amounts of ink droplets, and all the nozzles of ink K eject the same amount of ink. Each head chip is provided with a discharge heater (electrothermal converter) at its nozzle, generates bubbles in the ink by the thermal energy generated by the heat, and discharges the ink by the pressure of the bubbles. And the magnitude of the amount of ink droplets to be ejected is
This is made possible by providing a relatively large ejection heater for a nozzle that ejects large ink droplets and a relatively small ejection heater for a nozzle that ejects small ink droplets. It is needless to say that any known configuration may be used as the configuration for varying the discharge amount.

In the example shown in FIG. 1, two head chips are prepared for each of C, M, and Y inks, and each chip is provided with a nozzle for discharging a different amount of ink droplets. More specifically, nozzles that eject different amounts of ink for each color ink (in the figure, a large circle ejects a relatively large ink droplet, and a small circle ejects a relatively small ink droplet. (Similar in FIGS. 2 and 3)
Are alternately arranged in each nozzle row. As described above, the K ink head chip includes only nozzles that eject relatively large ink droplets. This is because black is recorded at a high density. The nozzles for ejecting different amounts of ink are arranged for each color ink head chip, but the heater board is common.

In the example shown in FIG. 2, two head chips are provided for each of the C, M, and Y inks, each having only nozzles for discharging large or small ink droplets. The nozzle arrays of the two heads that eject ink droplets of the same size of the respective color inks are arranged so as to be shifted from each other in a direction orthogonal to the scanning direction of the heads. Records can be made.

Further, the head chips of the respective color inks shown in the figure are attached to each other to form an integrated recording head.

The example shown in FIG. 3 has the same nozzle and head configuration as that shown in FIG. 2, except that the yellow head has only nozzles for discharging relatively large droplets. And different. This is because yellow is hardly noticeable and there is a case where the necessity of forming small dots is small.

This embodiment uses a recording head having nozzles for ejecting large and small ink droplets for ink of a predetermined color as described above, as will be described later with reference to FIGS. The print data of each nozzle is created.

FIGS. 4 (a) to 4 (e) and FIGS. 5 (a) to 5 (d)
FIG. 4 is a diagram schematically showing a nine-level index pattern according to the above-described conventional technology. As described above, for example, 8-bit multi-valued image data for each pixel is divided into 9 levels based on a predetermined threshold and converted into 4-bit pattern data corresponding to each level. In particular,
For example, 8-bit image data has a gradation value of 0-25.
Each of the threshold values obtained by dividing 5 into eight is associated with 4-bit pattern data. Then, any of the index patterns of level 0 to level 8 is specified by the 4-bit pattern data. Of these index patterns, the level 0 pattern has no dots
(White background), level 8 pattern is a pattern in which large dots are arranged at all positions to represent the highest density.

FIG. 6 is a graph showing the ink ejection rates (indicated by the signals R ', G', and B ') when the dot patterns obtained by the index patterns shown in FIGS. 4 and 5 are used. (Ratio of dots covering pixels)
FIG.

As shown in FIGS. 4 and 5, when an index pattern is used, up to level 4, that is, up to 128 R'G'B 'input values shown in FIG. By forming, the injection rate is 0
% To approximately 50%, and a smooth gradation can be obtained. However, even if the injection rate changes linearly, as described above, the index pattern determines the arrangement of large and small dots in a uniform manner between these dots in accordance with the pattern data. Since the range of gradation values that can be represented by the pattern data is uniformly assigned to each level, the input level is 1
Up to 28, only small dots are arranged.
As a result, as described above, there arises a problem that a streak of an image is conspicuous in an intermediate gradation portion.

On the other hand, it is considered that large dots are arranged even at intermediate levels by adjusting the contents of the index pattern. However, even if an attempt is made to arrange large dots at a level at which large dots are not originally arranged, the level corresponds to a relatively low gradation range in the state of image data as described above. Large dots will be arranged in the range of the key. In this case, if the ejection data is generated as an index pattern using, for example, all large dots without considering the gradation property, a problem such as an increase in granularity in a highlight portion is caused. Also, in order to arrange large dots in the range of halftone, etc., if the threshold value for determining the correspondence between the image data and each level of the index pattern is changed, discontinuity of density at the transition of pattern etc. Arises
Smooth gradation expression cannot be realized.

This embodiment also makes it possible to relatively easily change the dot arrangement while maintaining smooth gradation with the following configuration.

FIG. 7 is a flowchart showing a print data creation processing procedure executed by the ink jet printing apparatus of this embodiment. Note that, of course, the processing described below may be executed by the host device to obtain binary data, and the binary data may be sent to the recording device.

When a process relating to a predetermined color image is performed by the host computer, and as a result image data is sent to the present apparatus, in step S71 the image data RG
A process for inputting B is performed. Then, Step S72
Then, predetermined color correction processing is performed on this signal to obtain 8-bit image data R'G'B '.

Further, a color conversion process is performed in step S73. That is, for image data R'G'B ', R, G,
From the image data represented by the color space B, C, M,
The image data is converted into image data of a color space of Y and K. This process is based on the C, M, and C signals previously corresponding to the R ', G', and B 'input signals.
This is performed by referring to an LUT (look-up table) storing the values of Y and K.

FIG. 8 is a diagram schematically showing the contents of this LU #. As shown in FIG.
T outputs C, M, and Y data corresponding to large ink droplets as well as data SC, SM, and SY corresponding to small ink droplets as conversion data for each of C, M, and Y. More specifically, in relation to be described later with reference to FIG. 10A, 8-bit image data K, C, M, SC, and the like stored in correspondence with combinations of values of data R ′, G ′, and B ′, respectively.
It outputs SM and SY data.

Next, in step S74, each of K, C, M, SC, SM, and SY colors 8 obtained by the color conversion process is processed.
The n-value processing is performed on the bit image data. In the present embodiment, quinary processing is performed on each color image data. As a result, 4-bit (0000 to 0100) data can be obtained, and binary data used when discharging from an index pattern corresponding to each of the quinary levels can be obtained. Specifically, as described in detail in FIG. 9, large and small ink droplets of each color ink are
The ejection data of each nozzle for forming a dot pattern of × 2 can be obtained. The data obtained as described above is developed in the recording buffer in step S75.
The method of obtaining the final binary ejection data from the 8-bit image data of each color of K, C, M, SC, SM, and SY is not limited to the method using the above-described index pattern. Any known method of obtaining binary data from 8-bit data can be used as long as the large and small dots are obtained independently.

FIG. 9 is a diagram mainly showing a configuration of a recording buffer in the present recording apparatus.

The printer driver 2 shown in FIG.
Reference numeral 11 denotes software for creating image data in the host device and transferring the created data to the recording apparatus.

The controller 200 of the printing apparatus according to the present embodiment performs the operations of K, C, M, Y, SC, SM,
The processing of writing the SY data into the respective recording buffers 205 as 2-bit data for each color is performed by the distribution circuit 207 (step S75).

More specifically, it is assumed that 2-bit data is written for one pixel of 360 dpi for cyan C data, for example. At this time, in the present embodiment, buffers C1 and C2 for nozzles C1 and C2 of large ink droplets are used.
, Two bits each, and a total of four bits. Thereby, for each of two nozzles C1 and C2 that eject large ink droplets corresponding to one pixel,
0 to 2 ink ejections can be set, and 0 to 4 large ink droplet ejections in total can be set. Similarly, for the SC corresponding to the cyan small ink droplet, the nozzle SC
The configuration is such that a total of 4 bits, 2 bits each, are written into the buffers SC1 and SC2 for 1 and SC2, and 0 to 4 ink ejections can be set for small ink droplets. Any of the nozzle arrangements for ejecting large and small ink droplets can be used as shown in FIGS. 1 to 3. In recording each pixel, two nozzles separated by one nozzle pitch are used for each of the large and small ink droplets in this arrangement. This makes it possible to form a 2 × 2 dot pattern of large and small dots in one scan. Then, based on the print data generated as described above, each head is driven by the head driver 240 to discharge each ink.

That is, when each nozzle of the head reaches the pixel position where the ink is actually ejected, the data in each buffer is read into the register in each head, and the ink is ejected. As a result, the dot arrangement from level 0 to level 4 shown in FIG.

FIGS. 10 (a) and 10 (b) show input levels and ejection levels when recording data for ejecting different amounts of ink of the same color is formed independently in accordance with the size of droplets. It shows the relationship between the quantities.

FIG. 10A specifically shows the conversion contents of the table shown in FIG.
The conversion output for C and SC among the conversion outputs for the input of the color indicated by the point on the ITE axis will be described as an example. FIG. 10B is a diagram showing the ink ejection ratio finally obtained corresponding to the input value.

As shown in FIG. 10A, in the setting of LU #, the C data corresponding to the large ink droplet is set to an intermediate gradation value of 128 or more (left side from the center in the figure; density gradation). In FIG. 10B, the total of the data and the SC data corresponding to the small ink droplets shows the linear gradation change shown in FIG. 10B. Note that this LU
The contents of Т can be set by performing simulations and experiments in advance. This makes it possible to use large ink drops in the halftone area,
In this area, an image can be recorded by mixing large and small ink droplets. As a result, even if the small ink droplet is distorted, the large ink droplet having a large kinetic energy lands stably, thereby making it difficult to recognize a streak or the like.

The 8-bit print data of each of the large and small ink droplets obtained as described above is converted into 4-bit print data corresponding to two nozzles for each pixel by the quinary processing as described above. However, the adjustment of the arrangement pattern of large and small dots (in this embodiment, the contents of the index pattern) determined by this can be performed independently for each dot. Specifically, as described above, the color conversion table (LUＬ) shown in FIG. 10A is determined under the constraint that the total relationship shown in FIG. As long as the pattern satisfies the respective data values of K, C, M, Y, SC, SM, and SY, the size of the dots to be arranged and their positions are basically arbitrary. In other words, FIG.
Can be performed independently for each of the large and small ink droplets in each mode.
The dot arrangement obtained thereby can be determined independently. As a result, it is possible to easily adjust the dot arrangement corresponding to each gradation value of the image data, and it is possible to perform recording using large dots at an intermediate density gradation or lower.

Further, in this case, even if the relative balance of the amount of ink droplets is changed due to the design, the look-up table in the color conversion process and the mode of the above-mentioned n-value conversion process can be changed. It can be easily handled.

FIG. 11 is a perspective view showing a schematic configuration of the ink jet recording apparatus of the above embodiment. The recording device 50 of the present example is a serial scan type recording device,
The carriage 53 moves the arrow A by the guide shafts 51 and 52.
Are movably guided in the main scanning direction. The carriage 53 is reciprocated in the main scanning direction by a driving force transmission mechanism such as a carriage motor and a belt for transmitting the driving force. On the carriage 53, one of the recording heads shown in FIGS. 1 to 3 and an ink tank 54 for supplying ink to those recording heads are mounted for each ink color. The recording head and the ink tank 54 may constitute an integrated ink jet cartridge. After the paper P as a recording medium is inserted from an insertion port 55 provided at the front end of the apparatus, the transport direction is reversed, and then transported by the feed roller 56 in the sub-scanning direction indicated by arrow B. The recording device 50 performs a recording operation of ejecting ink toward a print area of the sheet P on the platen 57 while moving the recording head in the main scanning direction;
An image is sequentially recorded on the paper P by repeating the transport operation of transporting the paper P in the sub-scanning direction by a distance corresponding to the recording width.

FIG. 11 in the moving area of the carriage 53
A recovery system unit 58 is provided at the left end of the recovery unit 58 so as to face the ejection port forming surface of the recording head mounted on the carriage 53. The recovery system unit 58 is provided with a cap capable of capping the discharge port of the recording head, a suction pump capable of introducing a negative pressure into the cap, and the like, and a negative pressure is formed in the cap covering the discharge port. With the introduction, the ink is sucked and discharged from the discharge port, and a recovery process is performed to maintain a good ink discharge state of the recording head.
Further, by ejecting ink that does not contribute to an image from the ejection port toward the inside of the cap, a recovery process can be performed to maintain a favorable ink ejection state of the recording head.

In the above embodiment, the case where a head for ejecting ink is used has been described as an example, but the present invention is not limited to this example. The present invention can be applied to any type of head using a recording element in which the size of dots to be formed can be changed.

<Other Embodiments> The present invention, as described above,
The present invention may be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, and the like) or may be applied to an apparatus including one device (for example, a copying machine and a facsimile machine).

Further, software for realizing the functions of the above-described embodiment is installed in a computer connected to the various devices or in a system so as to operate various devices so as to realize the functions of the above-described embodiment. The present invention also includes a program code supplied and executed by operating the various devices according to a stored program in a computer (CPU or MPU) of the system or apparatus.

In this case, the program code itself of the processing shown in FIG. 7 realizes the function of the above-described embodiment, and the program code itself and means for supplying the program code to the computer, for example, A storage medium storing such a program code constitutes the present invention.

As a storage medium for storing the program code, for example, a floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-R
An OM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the supplied program code, not only the functions of the above-described embodiment are realized, but also the OS (operating system) running on the computer, or another program. Needless to say, the program code is included in the embodiment of the present invention even when the functions of the above-described embodiment are realized in cooperation with application software or the like.

Further, the supplied program code is stored in a memory provided in a function expansion board of a computer or a function expansion unit connected to the computer, and thereafter, based on the instruction of the program code, the function expansion board or the function expansion unit. It is needless to say that the present invention includes a case where the CPU or the like provided in the first embodiment performs a part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0048]

As described above, according to the present invention, the print data corresponding to each of the printing elements having different sizes of dots to be formed in the print head is converted into a total gradation change by these dots. Since the print data is generated under predetermined conditions such as linearity, when the generated print data is converted into dot data for forming the dots having different sizes in one pixel, the above-described predetermined conditions are used. The conversion can be performed for each of a plurality of dots having different sizes without consideration. This allows
The conversion process can be arbitrarily set for each dot under the above-mentioned predetermined conditions.

Further, by arranging larger dots in the density expression not more than the intermediate value of the density value width that can be expressed by dot formation, it is possible to mix larger dots and smaller dots with the density not more than the intermediate value. it can.

As a result, for example, even if an ink droplet having a small amount of ink is affected by a distortion or the like, it is possible to suppress the disturbance of the image. In addition, in the configuration using the conventional index pattern, the switching (connecting) of the dot arrangement is unnatural and causes a problem on the image.On the other hand, this arrangement can be easily changed only by changing the output table or the like. And the degree of freedom of design can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a recording head used in an ink jet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating another example of a recording head used in the ink jet recording apparatus according to one embodiment of the present invention.

FIG. 3 is a diagram showing still another example of a recording head used in the ink jet recording apparatus according to one embodiment of the present invention.

FIGS. 4A to 4E are diagrams schematically showing an index pattern used in conventional print data creation.

FIGS. 5A to 5D are diagrams schematically showing index patterns similarly used in conventional print data creation.

FIG. 6 is a diagram illustrating a relationship between print data and an ink ejection ratio when the index pattern is used.

FIG. 7 is a flowchart illustrating print data creation processing according to an embodiment of the present invention.

FIG. 8 is a diagram schematically showing a look-up table used in color conversion in the above processing.

FIG. 9 is a diagram illustrating a process of storing data obtained in the data creation process in a buffer.

10A and 10B show the relationship between the input level and the ejection amount when print data for ejecting different amounts of ink in the same color is formed independently for each droplet size. FIG.

FIG. 11 is a perspective view illustrating a schematic configuration of an inkjet printer according to an embodiment of the present invention.

[Explanation of symbols]

 200 Controller 205 Recording Buffer 207 Spreading Circuit 211 Printer Driver 240 Head Driver

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Jin Sugimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Kiichiro Takahashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Osamu Iwasaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hitoshi Nishikori 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. ( 72) Inventor Go Yazawa 3- 30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Toshiyuki Chikuma 3-30-2 Shimomaruko 3-chome, Ota-ku, Tokyo ) 2C056 EA04 EC75 EC76 EE02 2C262 AA02 AA27 AB13 BB01 BB10 BC07 EA04 5C051 AA02 CA04 DA06 DA10 DB02 DC07 DE05 DE09 DE31 EA01 5C074 AA05 BB16 DD05 DD24 DD28 FF15 GG09

Claims (13)

[Claims] 1. A recording apparatus for performing recording on a recording medium using a recording head having recording elements having different sizes of dots to be formed, wherein the recording elements having different sizes of the dots formed by the recording head. Data generating means for generating print data corresponding to each of the above under predetermined conditions; and means for converting the print data generated by the data generating means into dot data for forming dots in each pixel. And a conversion unit for performing a process of independently converting each of the dots having a different size. 2. The predetermined condition for generating the print data is that the print data of an image printed by dots formed based on print data corresponding to each of print elements having different sizes of dots to be formed. 2. The recording apparatus according to claim 1, wherein a condition is that a density change with respect to the image is linear. 3. The dot data obtained by conversion by the conversion means, wherein larger dots are arranged at a density equal to or less than an intermediate value of a density value width that can be expressed by forming dots based on the dot data. 3. The recording apparatus according to claim 2, wherein: 4. The recording apparatus according to claim 3, wherein the recording element includes an ink ejection port for ejecting ink. 5. The recording head according to claim 1, wherein the ink ejection openings for ejecting different amounts of ink of the same color are arranged in parallel in the scanning direction of the recording head, and the size of the ink ejection openings for ejecting the different amounts of ink is increased. 5. The recording apparatus according to claim 4, wherein dots form different dots. 6. The recording head according to claim 1, wherein the ink ejection ports for ejecting different amounts of ink of the same color are alternately arranged in a direction orthogonal to the scanning direction of the recording head, and the ink ejection openings for ejecting the different amounts of ink are provided. The recording apparatus according to claim 4, wherein dots having different sizes are formed according to the size of the recording medium. 7. The recording head according to claim 1, wherein a group of ejection ports for ejecting inks of a plurality of colors and a group of other ejection ports for ejecting inks of the plurality of colors are orthogonal to a scanning direction of the recording head. The recording apparatus according to claim 5, wherein the recording apparatus is arranged symmetrically about an axis. 8. The printing apparatus has a plurality of printing buffers corresponding to different amounts of ink of the same color, and selectively stores the dot data in the plurality of printing buffers to form a corresponding ink ejection. The recording apparatus according to claim 4, wherein the ink is ejected from an outlet. 9. A method for creating print data used in a printing apparatus that prints on a print medium using a print head having print elements having different sizes of dots to be formed, comprising: Recording data corresponding to each of the recording elements having different sizes is generated under a predetermined condition, and the recording data generated by the data generating unit is converted into dot data for forming dots by arranging dots in each pixel. Means for converting each of the dots having a different size independently for each of the dots. 10. The predetermined condition for generating the print data is that the print data of an image printed by dots formed based on print data corresponding to each of print elements having different sizes of dots to be formed. 10. The recording data creation method according to claim 9, wherein a condition is that a density change with respect to is linear. 11. The dot data according to claim 10, wherein the dot data arranges larger dots in a density expression equal to or smaller than an intermediate value of a density value width that can be expressed by forming dots based on the data. Recording data creation method. 12. The method according to claim 11, wherein the recording element includes an ink ejection port for ejecting ink. 13. A program for causing an information processing apparatus to perform a print data creation process, wherein the print data creation process performs printing on a print medium using a print head including print elements having different sizes of dots to be formed. This is a process for creating print data used in a printing apparatus, wherein the process generates print data corresponding to each of the print elements having different sizes of dots to be formed of a print head under predetermined conditions, Means for converting the recording data generated by the means into dot data for forming dots by arranging the dots in each pixel, the method comprising independently converting each of the dots having a different size. A program characterized by the following.