JP2007196483A - Ink-jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording device which uses a recording head having a plurality of head chips arranged therein, wherein the ink-jet recording device can carry out link processing that exhibits beautiful recorded image at a joint between the head chips even if the recording head is inclined. <P>SOLUTION: The recording device uses the recording head in which the recording head chips are arranged in a manner overlapping each other in a recording element row direction in a recording area. In the recording device, an inclination of a recording medium in a relative moving direction to the recording head, with respect to a perpendicular direction to the recording element row of the recording head, is detected, and a pixel shifting amount of recording data in the recording element row direction for each recording element row present in the perpendicular direction to the recording element row, is set according to the inclination amount of the recording head. By shifting pixels, inconveniences of alternate formation of white streaks and dark streaks at the joint (in the case of tight link), or uneven thinning (in the case of gradation link of exclusive distribution by ED) are eliminated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a recording head chip having one or a plurality of rows in which a plurality of printing elements are arranged in a row, and several tens to hundreds of tens of printing elements in the direction of the printing device row for each color of the printing color material at the end of the head chip. By using multiple recording heads arranged in a staggered pattern with overlapping lengths of minutes, the recording medium is applied to the recording medium while moving the recording medium relative to the direction perpendicular to the recording element array direction. The present invention relates to a recording method for eliminating the generation of white streaks and thin streaks at the joints between head chips in a recording apparatus for recording.

  2. Description of the Related Art Conventionally, an ink jet recording apparatus that includes an ejection nozzle group as a plurality of recording element arrays and records an image on a recording medium using these ink jet heads is known. In such a recording apparatus, recording is performed while moving the recording head relative to the recording medium in a direction perpendicular to the ejection nozzle row, and then the recording medium is moved in the direction of the ejection nozzle row to about 1 of the ejection nozzle row length. / n (n is an integer greater than or equal to 2), and the multi-pass printing serial printing device that records the nozzle nozzle width area in n times is inexpensive and has high image quality. .

  Here, in this method, in order to improve the recording speed, not only the drive frequency of the print head is increased, but also the number of discharge nozzles per color arranged in the print head is increased, that is, the length direction of the discharge nozzle row Increasing the length of the recording head has been advancing. However, along with the increase in length, it is becoming difficult to increase the length with one chip due to technical problems and cost problems. Therefore, there is a possibility that a plurality of head chips per color are arranged in the direction of the recording element array (ejection nozzle array in the ink jet) direction to form the recording head of the serial recording apparatus from a certain stage after becoming difficult. There is.

  In addition to the serial recording device, a recording head having a recording medium width of one recording pass is formed by using a long head constituted by arranging a plurality of recording head chips provided with a recording element array composed of a plurality of recording elements in the recording element array direction. In the full-line recording apparatus for recording with the above, a long head corresponding to the width of the recording medium is first required before the drive frequency of the recording head is improved for high-speed recording, unlike serial recording. In this case, there is an option of making a long head with one chip to make a long head, but due to the size of the recording medium, it is apt to be required to be longer than the length required for the serial recording device. Technical and cost issues are greater. In addition, there is a problem that a head chip has to be created for each model having different recording media size support ranges.

  Therefore, if a long head is made by connecting a plurality of recording head chips shorter than the width of the recording medium, technical problems and cost problems in manufacturing the head are reduced.

  However, when multiple head chips are connected, due to the mounting position accuracy between the head chips, the arrangement of the recording dots formed on the recording media is more disturbed than at the head chip joints, resulting in image quality degradation. Tends to stand out. In particular, in the case of 1-pass recording in which recording is performed with one recording pass, or in the case of recording with less than 2 passes such as a multi-pass recording type serial recording apparatus, there is a possibility of a problem.

Therefore, a number of patents have been filed in advance regarding issues related to improving the mounting accuracy between head chips, image processing at joints, and the arrangement of recording elements at joints to prevent deterioration in image quality due to head chip mounting accuracy. Has been.
For example, Patent Document 1, Patent Document 2, and Patent Document 3 can be cited as conventional examples.
JP 2001-212991 A JP-A-10-278246 Japanese Patent Application Laid-Open No. 09-234860

  However, when the head chips are arranged in a staggered manner as shown in FIG. 3, the recording head and the recording medium move relative to each other in a direction inclined with a deviation from a designed angle (generally, a direction perpendicular to the recording element array). When recording is performed, the positional relationship in the recording element array direction shifts for each recording element array as shown in the figure, and the head chip end alternately approaches the recording element array direction and becomes widened. More specifically, the recording element arrays having the same positional relationship in the direction perpendicular to the recording element array have a relationship of being shifted in the recording element array direction by the same amount and recorded on the recording medium. Therefore, even if the mounting accuracy of the head chip is sufficiently high at the head chip end, if the recording head and the recording medium are tilted away from the designed angles, image quality deterioration occurs at the head chip end.

  Here, the inventors have confirmed that if the positional relationship between the head chips that record the same color is shifted on the recording medium even with a fraction of the recording dot diameter, the joint between the head chips can be seen. When three or more chips are connected together, as shown in FIG. 2, white stripes and dark stripes are alternately generated at the tip end in the nozzle row direction, and an overlapping area is provided in the recording element row direction at both tip ends. As a result, when the usage ratio is changed little by little, a thin stripe is likely to occur at both ends of the chip and the entire joint.

  On the other hand, after improving the mechanical accuracy, the distance between the recording element arrays that record the same color in the positional relationship that is farthest in the direction perpendicular to the recording element array is brought close to the range that can be guaranteed with the mechanical accuracy. A proper solution is to use a head configuration. However, since the inkjet dot size has recently become smaller, it has been calculated that it would be difficult to increase the mechanical accuracy to such a level that image quality does not deteriorate.

  For example, if the resolution in the recording element array direction is 1200 dpi, the distance between the recording elements is 21 μm, the distance between the head chips is 20 mm, and the design relative movement direction of the recording head and the recording medium is perpendicular to the recording element array, the recording head and the recording medium The angle shift required to shift one pixel while recording with a relative displacement of 20 mm is 1/1000 times the aspect ratio, which is very severe. In practice, the angle of the relative movement direction of the recording head and the recording medium tends to vary due to the convenience of mechanical accuracy to the extent that the recording position shift in the recording element array direction of about 10 to 30 μm occurs. However, if the recording dot diameter is about 33 μm that can fill the diagonal line of the pixel, a recording position shift of several μm can be visually recognized, but this recording position shift is due to the convenience of mechanical accuracy. It occurs easily.

  When a plurality of recording head chips shorter than the width of the recording medium are connected without integrally lengthening the head chip, the recording element array having the positional relationship that is farthest in the direction perpendicular to the recording element array It is difficult to make the distance between them zero, and in the case where an overlapping region is provided in the direction of the recording element array at both chip ends, the distance between the recording element arrays does not become zero. Therefore, unless the recording material is tilted away from the direction perpendicular to the recording medium in the relative movement direction of the recording head and the recording medium and recorded at the same position on the recording medium, the effect of the recording position deviation cannot be removed. .

  The present invention has been made in view of the above conventional example, and in a serial recording apparatus or a full line recording apparatus using a recording head in which a plurality of head chips are arranged in the recording element array direction, the recording head and the recording medium are as designed. It is an object of the present invention to provide a recording apparatus capable of performing a connecting process so that the connection between the recording head chips can be clearly seen even when the relative movement is performed at an angle deviated from the angle.

  In order to achieve the above object, the recording apparatus of the present invention uses the following means. Note that the object of the present invention is to overlap the recording element array direction at the joint between the recording head chips of a serial recording apparatus or a full line recording apparatus using a recording head in which a plurality of head chips are arranged in the recording element array direction. This is the case when there is a possible area. In that case, measure the amount of deviation between the recording head and the recording medium from the designed angle (generally, the direction perpendicular to the recording element array), and based on this, the same positional relationship in the direction perpendicular to the recording element array The amount of deviation in the recording element array direction is calculated for each recording element array. In addition, by shifting the recording data in the direction of the recording element array in units of pixels for each recording element array having the same positional relationship in the direction perpendicular to the recording element array, the closer one of the adjacent recording elements can be selected. For this reason, a means is used in which the deviation on the recording medium is suppressed to a minimum of half or less of the pixel unit, and density unevenness at the end of the recording head chip is reduced.

  Hereinafter, preferred means for solving the problems will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram showing an outline of means for solving the problems in the present invention.

  The subject of the present invention is both a serial type and a one-pass full-line type recording apparatus, but a one-pass full-line type recording apparatus, which requires a long head even when a head chip is connected, is mainly used. This is mainly described. For the serial recording device, the recording head and the recording medium are shifted from the designed angle relative to each other at the joint between the head chips except for the portion other than the problem solved by the present invention, such as the recording position deviation between the recording passes. The problem caused by doing this is similar to the full line system in which only one path is seen, and can be solved by the present invention as in the full line system. Therefore, it is omitted from the description.

  First, using a long head composed of a plurality of recording head chips provided with a recording element array composed of a plurality of recording elements arranged in a staggered manner with overlapping recording areas in the recording element array direction, the recording media width is set to 1 A case of a full-line recording apparatus that records in one recording pass will be described.

  1 and 2 show that the recording head chip and the recording medium are designed when the head chips are arranged so that the recording head and the recording medium move relative to each other in the direction perpendicular to the recording element array at an angle as designed. It is the figure which showed what happens if it inclines from a street angle and moves relative. When moving as designed, the pitch of dots recorded on the recording medium by each recording element between the head chips is equal to the pitch between the recording elements of each chip. However, as shown by the wavy lines in FIG. 2, when the recording head and the recording medium move out of the designed angle, the dot pitch between the chips and between the recording element arrays is shortened according to the amount of deviation. Or get longer. If the angle shift amount is further increased, it may be shifted by one pixel between chips or recording element arrays, or the order in the recording element array direction may be changed. As the distance between the recording element arrays is longer in the direction perpendicular to the recording element array direction, the deviation in the recording element array direction becomes larger due to the influence of the angle deviation. When the distance between the head chips in the direction perpendicular to the recording element array direction is large, first, the head chips are largely displaced.

  Therefore, as shown in FIG. 1, among the head chips arranged in a staggered manner, the head chip array in the same position in the direction perpendicular to the recording element array direction, that is, either the even-numbered chip or the odd-numbered chip is arranged in the recording element array direction. The recorded image data is shifted in units of pixels.

  Furthermore, when a plurality of recording element arrays for recording the same color are provided in the head chip, such as the head chip in FIG. 6, the recording element array having a long distance in the direction perpendicular to the recording element array direction in the head chip. If there is a large gap between the head chips and the deterioration of the print image between the head chips is not negligible, the dot arrangement order in the recording element array direction on the recording medium is correct between recording element arrays that record the same color. As described above, after the recording image data is exchanged between recording element arrays that record the same color, the recording data is shifted in units of pixels for each recording element array.

  Also, the amount of shift between colors may be adjusted by shifting the entire data in units of pixels between colors.

  Here, it is necessary to measure the amount of deviation of the recording head and the recording medium from the designed angle, and to record with an image in which the recording image data is shifted according to the amount of deviation at the time of recording. For this reason, it is necessary to devise a technique for minimizing the change in the amount of deviation from when the recording head and the recording medium are deviated from the designed angle until the recording is actually performed. In addition, since the amount of the recording head and the recording medium deviated from the designed angle fluctuates during recording, it is necessary to change the image along the way accordingly.

  Among these methods, there are several methods for reducing the change in the deviation amount from the measurement to the actual recording. For example, a plurality of recorded image data corresponding to a plurality of deviation amounts are prepared in advance, and after measurement, an image corresponding to the deviation amount is immediately recorded without waiting for an image conversion process. There is a way to suppress the amount change. As an example of the method, measure and create a plurality of images in the range of deviation that can change from the amount of deviation to the time of image conversion processing, measure the amount of deviation again at the end of conversion, If the recorded image data in the case where the deviation amount is close is selected and recorded immediately, the deviation amount change from the measurement to the actual recording can be suppressed small.

  As another example, when the amount of deviation changes periodically, for example, when it changes with the period of the drive system of conveyance, the amplitude and phase of the change are grasped by measurement. The amount of deviation can be predicted. Therefore, if the recording medium moves under the recording head and the recording timing is compared with the phase of the deviation amount change, the deviation amount is predicted, and if recording image data is prepared and recorded, the periodic deviation will occur. As long as the component deviating from the change in amount is small, it is possible to suppress the dot position deviation on the recording medium that is 1/2 or less of the pixel unit, which is the limit of the pixel unit recording position deviation.

  On the other hand, while the recording is in progress, the amount of the recording head and the recording medium deviated from the designed angle fluctuates, and there are several methods for changing the image during recording accordingly. There is a way.

  Broadly speaking, the method of maintaining the pixel shift amount of the recording data in the recording element array direction without changing the processing of the recording data within the page, and the recording data processing by changing the processing of the recording data within the page There is a method of changing the shift amount.

  Here, in the former, since the pixel shift amount in the recording element array direction of the recording data does not change in the middle of the page, the recording medium shifts in units of pixels in the recording element array direction while moving relative to the recording head. There is no step. For this reason, there is no problem with the level difference, but the influence of the range in which the amount of deviation between the recording head and the recording medium from the designed angle cannot be suppressed from the recording leading edge to the trailing edge of the page.

  In the latter case, the pixel shift amount in the recording element array direction of the recording data changes in the middle of the page. Therefore, while the recording medium moves relative to the recording head, the recording element array as shown in FIG. There is a level difference in the direction in units of pixels. Therefore, there is a possibility that a problem related to the level difference occurs.

  Therefore, in the latter case, the image break is detected and shifted in units of pixels. Alternatively, instead of determining the first decimal place of the optimal pixel shift amount by rounding off or rounding off, a dithering process, an error diffusion process, or the like is performed so as to make the step inconspicuous, as shown in FIG. In addition, devise measures such as making the steps frequently occur. Desirably, the frequency component of the step generation in the direction of relative movement of the recording medium with respect to the recording head should be set to a high frequency so that the frequency component is inconspicuous in terms of visual characteristics.

  According to the present invention, it is possible to perform recording in the recording element array direction at the joint between the recording head chips of a serial recording apparatus or a full line recording apparatus using a recording head in which a plurality of head chips are arranged in the recording element array direction. If there is an area, even if the recording head and recording medium deviate from the designed angle (generally in the direction perpendicular to the recording element array), the data can be shifted to the adjacent pixels, so the deviation is maximum. Since it becomes less than half a pixel, the gap between the recording heads on the recording medium at the joint between the recording head chips can be minimized to less than half of the pixel unit, and density unevenness at the end of the recording head chip is reduced. it can.

  The best mode for carrying out the present invention is as follows.

  The present invention provides a case where there are overlapping recording areas in the recording element array direction at a joint between recording head chips of a full line recording apparatus using a long recording head in which a plurality of head chips are arranged in the recording element array direction. In addition, the recording head and the recording medium measure the amount deviated from the designed angle (generally, the direction perpendicular to the recording element array), and based on this, the same positional relationship is established in the direction perpendicular to the recording element array. The amount of displacement in the recording element array direction is calculated for each recording element array. In addition, by shifting the recording data in the direction of the recording element array in units of pixels, the deviation on the recording medium is minimized to less than half of the unit of pixels, and density unevenness at the end of the recording head chip is reduced. This is what is implemented.

  FIG. 1 and FIG. 2 are objects in which the head chips are arranged so that the recording head and the recording medium move relative to each other in the direction perpendicular to the recording element array at the designed angle. When moving as designed, the pitch of dots recorded on the recording medium by each recording element between the head chips is equal to the pitch between the recording elements of each chip. However, as shown by the wavy lines in FIG. 2, when the recording head and the recording medium move out of the designed angle, the dot pitch between the chips and between the recording element arrays is shortened according to the amount of deviation. Or get longer. If the angle shift amount is further increased, it may be shifted by one pixel between chips or recording element arrays, or the order in the recording element array direction may be changed. As the distance between the recording element arrays is longer in the direction perpendicular to the recording element array direction, the deviation in the recording element array direction becomes larger due to the influence of the angle deviation. When the distance between the head chips in the direction perpendicular to the recording element array direction is large, first, the head chips are largely displaced.

  Therefore, as shown in FIG. 1, among the head chips arranged in a staggered manner, the head chip array in the same position in the direction perpendicular to the recording element array direction, that is, either the even-numbered chip or the odd-numbered chip is arranged in the recording element array direction. The recorded image data is shifted in units of pixels. By shifting the position, it is possible to correct a recording position shift due to the fact that the angle of the relative movement direction of the recording head and the recording medium varies due to the convenience of mechanical accuracy. The conspicuous image quality degradation concentrated between the head chips is mainly the case of the same color, and elimination of this is the main purpose of the present invention. Therefore, first, this correction is performed only for the recording element arrays that record the same color. However, since the amount of shift between colors also blurs the image, the entire data may be shifted in units of pixels between colors, and alignment may be further performed.

  Furthermore, when a plurality of recording element arrays for recording the same color are provided in the head chip, such as the head chip in FIG. 6, the recording element array having a long distance in the direction perpendicular to the recording element array direction in the head chip. If there is a large gap between the head chips and the deterioration of the print image between the head chips is not negligible, the dot arrangement order in the recording element array direction on the recording medium is correct between recording element arrays that record the same color. As described above, after the recording image data is exchanged between recording element arrays that record the same color, the recording data is shifted in units of pixels for each recording element array.

  At that time, a plurality of recording element arrays for recording the same color are provided, and a head chip such as that shown in FIGS. 6A, 6B, and 6D having a higher resolution in the recording element array direction than in the case of one array. In the case of use, the method of shifting is not to shift in units of one pixel in each column, but to shift the data in units of one pixel before disassembling the image data and distributing the data to multiple columns. It is desirable to process by the setup which distributes data to. By doing so, it is possible to shift the recording position not with the arrangement resolution of the recording elements in units of columns but with the arrangement resolution of the recording elements with a higher resolution integrated into a plurality of rows, which is advantageous.

  In addition, setting the recording element array direction to high resolution means that the recording position in the recording element array direction can be selected in finer increments, which is advantageous for the implementation of the present invention, and is a desirable form.

  Initially, since the distance between the head chips in the direction perpendicular to the recording element array is longer than in the head chips, emphasis was placed on shifting the data in units of pixels between the head chips, but the relative movement direction of the recording head and the recording medium When the angle deviated from the designed angle (generally in the direction perpendicular to the recording element array) increases, the recording element order in the recording element array direction between the recording element arrays is changed on the recording medium even inside the head chip. End up. Therefore, when the shifted angle is large, the range of the angle is divided, and the order of use of the recording element rows and the start of use of the short part are started so that the recording dot order in the recording element row direction on the recording medium is correct. Swap the position. In addition, when a plurality of recording elements are overlapped in the recording element array direction between the head chips and the recording duty is switched between the head chips with gradation as shown in FIG. It is also desirable to switch from the angle to the region that enters the gradation to delimit the range of the shifted angle.

  Here, let us consider how severe the angle of the relative movement direction of the recording head and the recording medium becomes to the deterioration of the image quality of the recorded image.

  Assuming that the distance between the head chips in FIG. 2 is L mm and the distance between the recording elements in the head chip is a μm, the recording head and the recording medium are shifted in the direction of the recording element array by a distance of L mm. The recording position in the recording element array direction is shifted by one pixel just by the fact.

  For example, if the resolution in the recording element array direction is 1200 dpi, the distance between the recording elements is 21 μm, the distance between the head chips is 20 mm, and the design relative movement direction of the recording head and the recording medium is perpendicular to the recording element array, the recording head and the recording medium The angle shift required to shift one pixel while recording with a relative displacement of 20 mm is 1/1000 times the aspect ratio, which is extremely sensitive and precise. Actually, the angle of the relative movement direction of the recording head and the recording medium tends to vary due to the convenience of mechanical accuracy to such an extent that the recording position shift in the recording element array direction of about 10 to 30 μm occurs. However, if the recording dot diameter is about 33 μm that can fill the diagonal line of the pixel, the recording position deviation of several μm can be visually recognized, but this recording position deviation is due to the convenience of mechanical accuracy. It occurs easily. Therefore, it is considered essential to perform feedback processing for shifting the recording data in units of pixels in accordance with the recording position deviation.

  Here, according to the recording position deviation, it is necessary to measure the amount of deviation between the recording head and the recording medium from the designed angle, and to record the image with the recorded image data shifted according to the amount of deviation at the time of recording. There is. For this reason, it is necessary to devise a technique for minimizing the change in the amount of deviation from when the recording head and the recording medium are deviated from the designed angle until the recording is actually performed. In addition, since the amount of the recording head and the recording medium deviated from the designed angle fluctuates during recording, it is necessary to change the image along the way accordingly.

  Among these methods, there are several methods for reducing the change in the deviation amount from the measurement to the actual recording.

  A system in which the amount of deviation periodically changes, for example, a conveyance system of a conveyance belt drive system or carriage reciprocation, such as a conveyance system of a full-line type recording apparatus in which a recording medium is conveyed by a belt or a serial recording apparatus in which a recording head is mounted on a carriage. In the case of a change due to the vibration period or the like, the amount of deviation at the time of recording can be predicted by measuring the amplitude and phase of the change through measurement. Therefore, if the recording medium moves under the recording head and the recording timing is compared with the phase of the deviation amount change, the deviation amount is predicted, and if recording image data is prepared and recorded, the periodic deviation will occur. As long as the component deviating from the change in amount is small, it is possible to suppress the dot position deviation on the recording medium that is 1/2 or less of the pixel unit, which is the limit of the pixel unit recording position deviation.

  On the other hand, when the system is not a system in which the amount of deviation changes periodically, for example, when the angle between the recording head and the recording medium tends to fluctuate irregularly, such as a full-line recording apparatus that records on a roll-shaped recording medium. Prepares a plurality of recorded image data corresponding to a plurality of deviation amounts to be conveyed in advance and immediately records an image corresponding to the deviation amount without waiting for an image conversion process after measurement. There are ways to suppress change. As an example of the method, measure and create a plurality of images in the range of deviation that can change from the amount of deviation to the time of image conversion processing, measure the amount of deviation again at the end of conversion, If the recorded image data in the case where the deviation amount is close is selected and recorded immediately, the deviation amount change from the measurement to the actual recording can be suppressed small.

  On the other hand, while the recording is in progress, the amount of the recording head and the recording medium deviated from the designed angle fluctuates, and there are several methods for changing the image during recording accordingly. There is a way.

  Broadly speaking, the method of maintaining the pixel shift amount of the recording data in the recording element array direction without changing the processing of the recording data within the page, and the recording data processing by changing the processing of the recording data within the page There is a method of changing the shift amount.

  Here, in the former, since the pixel shift amount in the recording element array direction of the recording data does not change in the middle of the page, the recording medium shifts in units of pixels in the recording element array direction while moving relative to the recording head. There is no step. For this reason, there is no problem with the level difference, but the influence of the range in which the amount of deviation between the recording head and the recording medium from the designed angle cannot be suppressed from the recording leading edge to the trailing edge of the page.

  In the latter case, the pixel shift amount in the recording element array direction of the recording data changes in the middle of the page. Therefore, while the recording medium moves relative to the recording head, the recording element array as shown in FIG. There is a level difference in the direction in units of pixels. Therefore, there is a possibility that a problem related to the level difference occurs.

  Among these, when the angle variation in the recording page is small, and the image distortion is small throughout the page and there is no problem, the former processing is performed. In order to reduce the image distortion throughout the page, the pixel shift amount is set near the central value of the angle shift in the entire page so that the pixel shift in the entire page in the set pixel shift amount is reduced. Is desirable.

  However, when the angle variation in the recording page is large and there is a portion where the image is conspicuous in the entire page, or in order to avoid the need to determine the presence or absence of the conspicuous portion, the latter It is a desirable form to implement after devising an appropriate process.

  As an example, first, an image break is detected and shifted in units of pixels.

  As another example, instead of determining the first decimal place of the optimum pixel shift amount by rounding off or rounding off, dithering or error diffusion processing is performed so that the level difference is not noticeable. Thus, as shown in FIG. 5, a contrivance is made such that steps are frequently generated. Desirably, it is desirable to set a high frequency so that the frequency component of the level difference generated in the direction of relative movement of the recording medium with respect to the recording head becomes a frequency component that is inconspicuous in terms of visual characteristics. That is, avoid 0.5 to 1 cycle / mm, which is conspicuous in visual characteristics, and avoid 0.5 to 2 cycle / mm if possible.

  It is further desirable to implement a combination of forms in which the above-described steps are frequently generated after detecting image breaks and giving priority to pixel shift here.

  The basis is based on the best mode for carrying out the invention, but there are partially different embodiments.

  A plurality of recording element arrays for recording the same color are provided, and the shift in the case of using the head chip shown in FIGS. 6A, 6B, and 6D, in which the recording element array direction is higher resolution than in the case of one array. However, in order to shorten the processing time, it is necessary to shift the data in units of one pixel before disassembling the image data and distributing the data to a plurality of recording element arrays, and then to distribute the data to the plurality of recording element arrays. Alternatively, a method may be used in which data is exchanged between recording element arrays from an image that has already been divided into recording element array units, and then shifted in pixel units in units of columns. However, it is carried out so that the order of the recording element array direction is correct with the dots recorded on the recording medium.

  In the case of FIGS. 6A, 6B, 6D, etc. in which a plurality of recording element arrays for recording the same color are provided and the direction of the recording element array is higher than in the case of one line, all the recording elements are used. A recording method is performed in which recording is performed only with a recording element array whose recording position is close to the desired shift amount in the recording element array direction. Since the resolution of the recording data is not increased, the data processing can be reduced and the processing time can be shortened, which is advantageous for the feedback system.

  When a plurality of recording element arrays for recording the same color are provided, and a connecting head is formed using a head chip as shown in FIGS. 6C and 6D having a plurality of recording element arrays at the same position in the recording element array direction, In accordance with the amount by which the recording head and the recording medium are deviated from the designed angles among the plurality of recording element arrays that are at the same position in the recording element array direction, there is a shift of less than a pixel unit in the recording element array direction between the chips. By selecting and using printing element rows that have a small positional relationship, and then shifting pixels in the printing element row direction as in the above-described best embodiment and Examples 1 and 2, high accuracy between chips The connection can be realized. In addition, there are a plurality of head chips that record first in the transport direction, but in order to make the usage frequency uniform and maximize the life of the head chip, the recording element array used for each page is changed, It is desirable to make the frequency of use uniform. The recording element array of the head chip that records first in the transport direction is a standard that determines the used recording element array of the head chip to be recorded later and the pixel shift amount. Processing is performed according to which recording element array is used for recording.

  In addition, if the amount of deviation between the recording head and the recording medium from the designed angle is small and the amount of deterioration in image quality cannot be visually recognized, a plurality of recording element arrays at the same position in the recording element array direction of each head chip are provided. Two or more may be used for sharing. An effect close to that of a pseudo multi-pass is produced, and it becomes easy to suppress recording density unevenness in the recording element array direction.

  The plurality of recording element arrays in the present embodiment indicates a case where there are a plurality of recording element arrays used in one recording pass in the same direction for the same color, and different recording element arrays are used in the forward direction and the backward direction. This is not the case for a fully bidirectional head chip.

  In the above-described best embodiment and Examples 1 and 2, a shift amount less than a pixel unit is not set, but when there is no sharp density edge such as text, for example, a photographic image such as a natural image In this case, an image at a position shifted vertically and horizontally by a fine unit smaller than a pixel unit from the original pixel grid may be generated by the complementing process and recorded. In this case, the original image data is converted into the recording resolution of the recording apparatus at the stage of the multi-value data before binarization, and the image range of the portion distributed to the recording element array to be shifted in pixels is extracted. An image at a position shifted vertically and horizontally by a fine unit less than a pixel unit from the pixel grid of the recorded image is generated. As a complementary processing method, nearest neighbors do not have the meaning of calculating less than a pixel unit, so use a method such as bilinear or bicubic that calculates based on multiple peripheral pixel values of the original pixel grid. . Once an image with a shifted pixel grid is generated, the images of all the recording elements are once integrated into the pixel positions that are as close as possible to each other without forcing image conversion of the intermediate pixel positions, and binarization is performed in that state. Do. Binarization may be performed without considering that the position is shifted, but may be considered. In the case of binarization by error diffusion, the distribution of error diffusion may be changed in a portion that becomes a boundary between printing element arrays in consideration of the deviation. Once binarization is performed, distribution is performed again for each printing element array. Record with the resulting image.

In the present invention, pixel shift when the recording head and the recording medium deviate from the designed angles. In the conventional example, when the recording head and recording medium deviate from the designed angle, Connecting head with recording element overlap area between head chip chips When the pixel shift amount in the transport direction is determined by rounding off while recording When the pixel shift amount is changed in small increments in the transport direction while recording (a) Head chip with high resolution by shifting multiple (2 rows) printing element rows in the direction of printing element row (b) High resolution by shifting multiple (4 rows) printing element rows in the direction of printing element rows Head chip (c) Head chip that has multiple recording element arrays at the same position in the recording element array direction but has not been increased in resolution (d) High resolution by shifting multiple (2 arrays) recording element arrays in the recording element array direction Head chip having a plurality of recording element arrays at the same position in the recording element array direction When changing the recording duty between head chips with gradation in a connecting head that has a recording element overlap area between head chip chips

Claims (9)

  A recording head chip having one or a plurality of rows in which a plurality of printing elements are arranged in a row is overlapped by a length corresponding to a plurality of printing elements in the printing element row direction for each color of the printing color material at the end of the printing head chip. In a recording apparatus for recording by applying a recording color material to a recording medium while relatively moving the recording medium in a direction intersecting the recording element array direction using a plurality of staggered recording heads arranged in a staggered form And a recording medium based on one of the recording head chip groups or recording element array groups having the same amount of inclination from the relative movement direction as designed for the recording medium or the position in the direction perpendicular to the recording element array. For each chip group or recording element array group having the same position in the direction perpendicular to the element array, the amount of deviation in the recording element array direction is measured, and the position in the direction perpendicular to the recording element array is the same. Record between each other Print data for each print head chip group or each print element row group in which the position in the direction perpendicular to the print element row differs from the reference but is the same with respect to a certain one of the print chip groups or print element row groups The pixel shift amount is set according to the previous tilt amount and shift amount, and the same amount of pixel shift is performed between the print head chip groups or the print element row groups having the same position in the direction perpendicular to the print element row. By performing this, a recording apparatus is characterized in that the generation of streaks at the joints between the head chips is eliminated for each color or each recording head.   2. The recording apparatus according to claim 1, wherein a one-pass recording method for recording the recording element array width at a time is used.   The amount of tilt in the direction perpendicular to the direction of the recording element array and the relative movement direction of the head of the recording medium is measured in real time during recording, and this is fed back, and the pixel shift amount of the recorded data is determined according to the amount of previous tilt. 3. The recording apparatus according to claim 1, wherein recording is performed while determining and changing the pixel shift amount.   Regarding the amount of inclination in the direction of relative movement between the direction perpendicular to the recording element array direction and the head of the recording medium, a recorded image is prepared in advance and the pixel shift amount is changed according to the amount of inclination in real time immediately before recording. 4. The recording apparatus according to claim 3, wherein one of the images prepared in advance is selected and recorded.   For the amount of inclination in the direction of relative movement between the direction perpendicular to the recording element array direction and the head of the recording medium, the amount of inclination at the time of recording is predicted based on the change up to the present, and the pixels are shifted according to the prediction. 4. A recording apparatus according to claim 3, wherein a recording image is prepared and recorded in advance by changing the amount.   6. The recording apparatus according to claim 1, wherein the pixel shift amount is changed in units of pages.   6. A recording apparatus according to claim 1, wherein a pixel shift amount is changed within a page.   When correcting the pixel shift amount of less than one pixel by converting it to a pixel unit shift amount, instead of rounding off less than one pixel, use dither or error diffusion in the relative movement direction of the recording head and the recording medium. The recording apparatus according to claim 7.   By configuring multiple recording element arrays for each color so that the recording element array direction is higher in resolution than one recording element array, the order of the dots recorded on the recording medium in the recording element array direction is correct. As described above, according to the amount of inclination in the relative movement direction between the direction perpendicular to the recording element column direction and the head of the recording medium, recording is performed by switching the column order to be used or by switching data between columns. The recording apparatus according to claim 1 to 8.

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