JP2013022883A - Recorder and processing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide constitution of a recorder to perform recording by switching a heating condition of a heating element while setting a heating element group divided into a plurality of areas as a unit, wherein unevenness is inhibited from occurring in a boundary zone between the areas.SOLUTION: The recording head records an image by switching the heating condition of the heating element while setting the heating element group divided into the plurality of areas in an arrangement direction of the heating elements as the unit, and includes: a calculation means that calculates a plurality of pieces of temperature information corresponding to the respective areas on the basis of detection values from a plurality of temperature detection elements disposed in the recording head; an image processing means which generates a set of a plurality of recording data by using masks for generating the set of recording data as many as the plurality of pieces of temperature information calculated from the respective areas; a determination means which determines the heating condition of the heating element on the basis of the plurality of pieces of temperature information calculated according to the respective areas; and a recording control means which performs heating control under the heating condition determined by the determination means for the corresponding heating element on the basis of the set of the plurality of recording data corresponding to the respective areas, thereby recording the image by ejecting ink from ejection ports arranged in the recording head.

Description

  The present invention relates to a recording apparatus and a processing method therefor.

  2. Description of the Related Art Conventionally, recording apparatuses that perform recording on recording media such as paper and OHP sheets are known. In a recording apparatus equipped with an ink jet recording head, in order to suppress the occurrence of density fluctuation and density unevenness, the ejection speed and directionality (landing accuracy) and the ejection characteristics regarding the ejection amount VDROP [pl / dot] are stabilized. I am trying.

  Here, among ink jet recording heads, there is known a recording head that uses bubbles generated by a heating element (hereinafter referred to as a heater) as means for ejecting ink droplets. In such a configuration, in order to ensure the above-described stability, for example, the pulse width of the pre-pulse of the heater (of the ink discharge amount) is adjusted according to the temperature of the recording head by using a divided pulse width modulation method (PWM control method). Changing technology is known. Thereby, the fluctuation | variation of the discharge amount resulting from a temperature fluctuation is suppressed.

  In the correction method described above, since the average discharge amount of the print head is controlled, it is possible to suppress changes in density due to temperature fluctuations of the print head during intra-page / inter-page printing. However, it is impossible to correct the density unevenness (unevenness in the connecting direction by the serial recording method) of the recording head itself, that is, the variation in the ejection amount for each nozzle. For this reason, density unevenness between a plurality of nozzles arranged in the recording head cannot be completely corrected, and thus density unevenness is particularly noticeable in an image having a uniform tone.

  Therefore, in order to deal with such density unevenness, a so-called head shading method: HS method is known in which density unevenness of a test pattern recorded by a recording head is read and a density signal for each nozzle (ejection port) is corrected. .

  In this method, unevenness correction (HS method) is performed on the basis of a predetermined output pattern (constant density signal), so that variations in ejection amount among a plurality of nozzles can be reduced to some extent. Therefore, this method can eliminate density unevenness of a pattern having a certain density (a pattern in which nozzles are used at a predetermined recording ratio).

  Here, in the technique of Patent Document 1, ejection pulses are applied to a plurality of density regions according to recording characteristics (ejection amount characteristics) for each nozzle so that an image free from density unevenness and density stripes can be recorded in all gradations. It has changed. In the technique of Patent Document 2, the overlap area can be increased or decreased in the width direction of the recording medium in order to widen the recording width, and further, the amount of ink shot (number of recording pixels) in this area can be changed. . Thereby, the density at the time of recording between a plurality of recording heads is made uniform.

Japanese Patent Laid-Open No. 05-220977 JP 2009-160745 A

  2. Description of the Related Art Conventionally, a recording apparatus provided with a so-called full line type recording head having a recording width corresponding to the width of a recording medium is known. In a recording apparatus having such a recording head, an image can be recorded on almost the entire surface of the recording medium by moving the recording head once relative to the recording medium.

  In the case of a recording apparatus employing such a long recording head, a plurality of nozzles arranged in the recording head may be divided into a plurality of regions, and recording may be performed by setting ejection conditions for each region. In such a configuration, when the same image is continuously recorded, a temperature distribution is generated in the recording head, and unevenness may occur between the regions.

  By detecting the temperature for each nozzle and setting the discharge pulse for each nozzle according to the detection result, the occurrence of such unevenness can be suppressed, but in this case, the configuration becomes very complicated, the main body size, the processing speed The reality is low in many respects, including cost. Even if the above-described shading method is used, unevenness can be reduced if the temperature is uniform, but unevenness may occur if temperature distribution occurs in the recording head.

  The present invention has been made in view of the above problems, and in the configuration in which recording is performed by switching the heating conditions of the heating elements in units of heating element groups divided into a plurality of areas, the occurrence of unevenness in the boundary areas of the areas It aims at providing the technology which enabled it to control.

  In order to solve the above problems, one embodiment of the present invention includes a recording head in which a plurality of heating elements that generate thermal energy for ejecting ink from ejection ports is arranged, and is arranged along the arrangement direction of the heating elements. A recording apparatus for recording an image by switching a heating condition of a heating element in units of heating element groups divided into a plurality of regions, and is arranged on the recording head along an arrangement direction of the plurality of heating elements Based on detection values from a plurality of temperature detection elements, a calculation means for calculating a plurality of temperature information corresponding to each region, and a set of recording data equal to the number of the plurality of temperature information calculated from each region is generated. Image processing means for generating a set of a plurality of recording data corresponding to each area by masking image data corresponding to each area using a mask for performing calculation, and corresponding to each area Based on the plurality of temperature information, a determination unit that determines a heating condition of the heating element when performing a recording operation using each of the plurality of sets of recording data in a corresponding region, and a plurality of units corresponding to each region On the basis of the set of recording data, the corresponding heating element is heated according to the heating condition determined by the determining means, thereby ejecting ink from the discharge ports arranged in the recording head, thereby generating an image. Recording control means for recording the.

  According to the present invention, in the configuration in which recording is performed by switching the heating conditions of the heating elements in units of heating element groups divided into a plurality of areas, it is possible to suppress the occurrence of unevenness in the boundary area between the areas.

1 is a diagram illustrating an example of an external configuration of a recording apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of an internal configuration of the recording apparatus 10 illustrated in FIG. 1. FIG. 3 is a diagram illustrating an example of a configuration of a recording head H illustrated in FIG. 2. FIG. 4 is a diagram illustrating an example of area division in the recording head H. FIG. 3 is a diagram illustrating an example of a circuit configuration provided for each region unit in the recording head H. The figure for demonstrating the outline | summary of the nonuniformity which generate | occur | produces between area | regions. The figure which shows the outline | summary of the recording result of the image shown in FIG. The enlarged view of the attention area | region 903 in the boundary area of FIG. The figure which shows the recording pattern of the attention area 903 shown in FIG. 8 in detail. FIG. 2 is a diagram illustrating an example of a configuration of a control system of the recording apparatus 10 illustrated in FIG. 1. 3 is a flowchart illustrating an example of a processing flow of the recording apparatus 10 illustrated in FIG. 1. The figure which shows an example of a modification.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, a recording apparatus using an ink jet recording method will be described as an example.

  The recording apparatus may be a single function printer having only a recording function, or may be a multi-function printer having a plurality of functions such as a recording function, a FAX function, and a scanner function. . Further, for example, a manufacturing apparatus for manufacturing a color filter, an electronic device, an optical device, a minute structure, and the like by a predetermined recording method may be used.

  In the following description, “recording” is not limited to the case where significant information such as characters and figures is formed, and it does not matter whether it is significant. Further, it also represents a case where an image, a pattern, a pattern, a structure, or the like is widely formed on a recording medium or a medium is processed regardless of whether or not it is manifested so that a human can perceive it visually.

  “Recording medium” represents not only paper used in general recording apparatuses but also cloth, plastic film, metal plate, glass, ceramics, resin, wood, leather, and the like that can accept ink. .

  Further, “ink” should be interpreted widely as in the definition of “recording”. Therefore, by being applied on the recording medium, it can be used for forming an image, pattern, pattern, etc., processing the recording medium, or processing the ink (for example, coagulation or insolubilization of the colorant in the ink applied to the recording medium). Represents a liquid that can be provided.

  FIG. 1 is a diagram showing an example of an external configuration of a recording apparatus according to an embodiment of the present invention.

  The recording apparatus 10 is provided with a so-called full line type recording head having a recording width corresponding to the width of the recording medium. More specifically, a nozzle row composed of a plurality of nozzles is provided so as to cover the recording width along a direction that intersects (in the present embodiment, orthogonal) with the conveyance direction of the recording medium. Each nozzle (discharge port) is provided with, for example, a heating element (heater) that generates thermal energy applied to the ink.

  Here, in the recording apparatus 10, a roll-shaped sheet is stored in the roll unit 12 as a recording medium. An upper cover 14 is attached to the upper portion of the main body so as to be freely opened and closed. By opening the upper cover 14, the user can see the recording head and the recording medium transport unit built in the main body.

  A front cover 16 is attached to the main body so as to be freely opened and closed. By opening the front cover 16, a user can see an ink tank that stores liquid ink supplied to the recording head H. . The upper cover 14 and the front cover 16 constitute an outer shell of the apparatus.

  In addition, a cutter 18 for cutting a recorded sheet is disposed in the main body. A power switch 20 of the recording apparatus 10 is disposed below the front cover 16, and operations for inputting various user instructions and displaying various information are provided above the front cover 16. A panel 22 is arranged.

  Next, an example of the internal configuration of the recording apparatus 10 shown in FIG. 1 will be described with reference to FIGS.

  First, before describing the internal configuration of the recording device 10, the host device 24 will be described. The host device 24 is a source of image information (image data) and is connected to the recording device 10. The host device 24 may be, for example, a digital camera or a card-shaped storage medium.

  As shown in FIG. 3, a plurality of recording heads H are arranged in parallel in the recording apparatus 10 along the conveyance direction (arrow A direction) of the recording medium (sheet) P. In this embodiment, four recording heads H (26K, 26C, 26M, and 26Y) corresponding to four colors of K (black), C (cyan), M (magenta), and Y (yellow) are provided. The arrangement order of the recording heads H is K, C, M, and Y from the upstream side in the sheet conveying direction, and each recording head is arranged with the recording width aligned along the sheet conveying direction. Note that the number of colors and the number of recording heads are not necessarily four, and can be changed as appropriate.

  These four recording heads H are full-line type recording heads as described above, and extend in a direction orthogonal to the sheet P conveyance direction (a direction orthogonal to the arrow A direction). The lengths of these four recording heads H are slightly longer than the maximum width (the length in the direction orthogonal to the sheet conveying direction) of the recording media that can be recorded by the recording apparatus 10.

  A recovery unit 40 is incorporated in the recording apparatus 10. The recovery unit 40 recovers the ink ejection state from the recording head H. The recovery unit 40 is provided with a capping mechanism 50, and the capping mechanism 50 removes ink from the ink discharge port forming surfaces 26Ks, 26Cs, 26Ms, and 26Ys of the four recording heads H.

  The capping mechanism 50 is provided independently for each recording head H. In FIG. 2, six capping mechanisms 50 are shown, but two of these are preliminary mechanisms when a recording head is added. The capping mechanism 50 includes a known blade, an ink removing member, a blade holding member, a cap, and the like. Further, the recovery unit 40 pressurizes the ink in each recording head H and simultaneously sucks the ink. Thereby, bubbles in the ink are removed while the ink is circulated between each recording head H and each sub tank (not shown).

  The sheet P is supplied from the roll unit 12 and is conveyed in the arrow A direction by the conveyance mechanism 30. The transport mechanism 30 includes a transport belt 30a for placing and transporting the sheet P, a transport motor 30b for rotating the transport belt 30a, a roller 30c for applying tension to the transport belt 30a, and the like.

  When recording on the sheet P, the recording apparatus 10 uses the recording head based on the image data (image information) after the recording start position of the sheet P being conveyed reaches below the black recording head 26K. Black ink is ejected from 26K. Similarly, ink of each color is ejected in the order of the recording head 26C, the recording head 26M, and the recording head 26Y to record a color image on the sheet P.

  In addition to the components and members described above, the recording apparatus 10 is provided with main tanks 28K, 28C, 28M, and 28Y that store ink supplied to the recording heads H (26K, 26C, 26M, and 26Y). A tube pump (not shown) for supplying ink to the recording head H and performing a recovery operation is also provided.

  Here, the plurality of nozzles arranged in the recording head H are divided into a plurality of regions including some of the plurality of nozzles. With reference to FIG. 4A, the division of the area in the recording head H will be described. FIG. 4A is a diagram of the recording head H viewed from the direction of the ink ejection surface.

  A plurality of (in this case, 2592) nozzles 60 are arranged in the recording head H. Here, the nozzles of the respective regions in the recording head H are indicated by numbers # 1, # 2, # 3.

  Further, in the recording head H, a plurality of nozzles (heaters) are divided into a plurality of regions along the arrangement direction. The heating condition of the heater is switched in units of the heater group divided into the plurality of regions.

  Here, nozzles # 1 to # 1296 per inch are provided in area 1, and nozzles # 1297 to # 2592 are provided in area 2 per inch. Although details will be described later, in the recording head H, it is possible to set heating conditions for a plurality of types of heaters (two types and three types in the present embodiment) in each region.

  Next, a temperature detection sensor (temperature detection element) provided in the recording head H will be described with reference to FIG.

  When recording is performed by ejecting ink from the recording head H, it is necessary to stabilize the speed and directionality (landing accuracy) of ink ejection and the amount of ink ejection. The part affected by temperature is large. Therefore, it is preferable to determine the heating condition of the heater according to the temperature.

  Therefore, the print head H is provided with a plurality (in this case, five) of temperature detection sensors (diode sensors) Di1 to Di5 along the nozzle arrangement direction. In the recording apparatus 10, the heating condition in each region in the recording head is determined based on these detection results.

  In this case, three temperature detection sensors are provided for each area in the recording head. Since only one temperature detection sensor is sufficient for temperature detection between the region 1 and the region 2, only the temperature detection sensor Di3 is connected.

  Here, a method for calculating the control temperature of each region (temperature representative of each region) for determining the heating condition of each region in the recording head H will be described.

(1) Average processing of detection values of each temperature detection sensor Since the detection value from the acquired temperature detection sensor Di includes a detection error due to noise, for example, an average value for four times is obtained to detect each temperature. The temperature at the sensor position.

(Formula 1)
(2) Calculation of average temperature in each region As one of the control temperatures for setting the heating conditions, detection results of three temperature detection sensors Di provided in each region in the recording head H (after the above average processing) Average value). For the calculation of the average value of the region 1, the temperature after the average processing of Di1, Di2, and Di3 obtained by “Expression 1” may be used. For the calculation of the average value of the region 2, the temperature after the average processing of Di3, Di4, and Di5 obtained by “Expression 1” may be used. Thereby, the control temperature for determining the heating condition of the heater corresponding to each of the region 1 and the region 2 is obtained.

  In the present embodiment, the control temperature between adjacent regions (between region 1 and region 2) is also obtained. As the control temperature between these regions, the average value of Di3 obtained by “Expression 1” may be used.

(Formula 2)
Next, an example of a circuit configuration provided for each area unit in the recording head H will be described with reference to FIG.

  The recording head H is provided with a circuit (head chip) corresponding to each region, and a first circuit and a second circuit are further provided on the circuit. The first circuit includes a shift register circuit 704, a latch circuit 705, and a heater selection circuit 706. The second circuit includes a shift register circuit 703, a latch circuit 702, and a heater selection circuit 707. It is composed of In addition, a circuit (head chip) provided corresponding to each region energizes the selector 708 that selects a drive signal from either the first circuit or the second circuit, or the heater 701 based on the drive signal. A driver 711 for performing the above is also provided.

  The recording head H operates based on a recording data set (IDATA1, IDATA2), a heat enable signal (HENB1, HENB2), a latch signal DLT, a recording clock signal DCLK, and the like. These signals are transferred from the main body of the recording apparatus 10.

  Here, the operation in the first circuit will be described. The first circuit operates based on the above-described IDATA1, HENB1, latch signal DLT, recording clock signal DCLK, and the like.

  When IDATA1 is transferred to the recording head H side, the first circuit stores the recording data in order from the 1296th bit of the shift register circuit 704. Note that IDATA1 is transferred in synchronization with DCLK704.

  First, the recording data transferred to the recording head side in synchronization with DCLK 704 is stored in the first bit (corresponding to 1seg), and the recording data transferred last is in the 1296th bit (corresponding to 1296seg). Stored.

  When a set of recording data for one line including invalid data (Null data) in the margin is transferred to the recording head H side, in the first circuit, the recording is performed at the timing when the latch signal DLT becomes active. A data set is held in the latch circuit 705.

  Subsequently, in the heater selection circuit 706, the first circuit takes a logical product of HENB1 (which plays a role in defining the heater energization time) and the set of recording data held in the latch circuit 705, and as a result. In response to this, a drive signal is output and the heater 701 is energized. Thereby, ink is ejected from the corresponding nozzle.

  Here, the set value of the control temperature for IDATA1 is calculated according to “Expression 2” for calculating the average temperature of each region described above. The set value of the control temperature for IDATA2 is calculated according to the average temperature of the temperature detection sensor Di3 based on “Expression 1” as the temperature between the regions. That is, different heating conditions may be set for IDATA1 and IDTA2. IDTA1 and IDATA2 are obtained by using different masks for the same image data. When IDTA1 and IDATA2 are added together, the original image data is obtained.

  The second circuit may perform the same control as described above, and thus the description thereof is omitted here. As described above, in the present embodiment, a plurality of print data sets are generated by using a plurality of types of masks corresponding to each region, and different heating conditions are set for each of the plurality of print data sets.

  In the above description, two systems of circuits are provided for one area. However, the present invention is not limited to this, and three or more circuits may be provided. For example, when three circuits are provided, the configuration shown in FIG. In this case, three sets of recording data and heating conditions can be set for one region.

  Next, the non-uniformity that occurs between the above-described regions will be described with reference to FIG. Here, the unevenness that occurs between the areas of the recording head will be described using the relationship between the temperature of the recording head (temperature detection result), the recording image, and the density of the recording image.

  In the recording apparatus, for example, it is assumed that an image 801 having a uniform density is continuously recorded for a long time. In this case, a temperature distribution as shown in the temperature detection result 802 is generated inside the recording head.

  In the region 1, since the image is continuously recorded with a uniform density, the temperature detection sensors Di1 to Di3 output equivalent detection temperatures (detection values). On the other hand, in the area 2, since the nozzles used for recording and the nozzles that are not mixed are mixed, the temperature detection sensors Di3 to Di5 output different detection temperatures.

  Here, in the conventional configuration, it is assumed that the heating condition of the heater is changed in order to control the ink discharge amount in accordance with the detection temperature of these detection temperature elements provided in the recording head H. In this case, since the heating condition is set according to the average temperature of each region, the target discharge amount can be achieved and an image with a uniform density can be recorded in the region 1 showing a detection temperature close to a constant.

  On the other hand, in the region 2, since a temperature difference is generated at each position with respect to the average temperature of the region, an image having a density as shown in the density 803 of the recorded image is recorded. . Looking at the concentration gradient only in the region 2, since the concentration gradient continuously changes, it is difficult to visually recognize it as unevenness. However, since there is a density difference (gap) in the boundary area between the region 1 and the region 2, even a slight gap is visually perceived as unevenness.

  FIG. 7 is a diagram showing an outline of the recording result of the image shown in FIG. That is, the recording result of an image recorded using the nozzles arranged in the entire area 1 and a part of the area 2 will be described. Reference numeral 901 indicates an image recorded by the technique of the prior art, and reference numeral 902 indicates an image recorded by the technique of the present embodiment.

  In the image 901 according to the conventional method, a density gap is generated in the boundary region between the region 1 and the region 2, and unevenness occurs. On the other hand, in the image 902 according to the method of the present embodiment, the occurrence of unevenness due to the density gap is reduced.

  This is because in the method of the present embodiment, data subjected to mask processing is transferred as IDATA1 and IDATA2 described in FIG. 6A in the boundary area between the area 1 and the area 2. . After performing such mask processing, different heater heating conditions are set in each region in accordance with the detection result of the temperature detection sensor.

  Here, this mask process will be described. FIG. 8 shows an enlarged view of the attention area 903 in the boundary area of FIG. Note that the attention areas 71 to 73 are processed by masks having different patterns, and here, three examples are shown as examples of the attention area.

  The nozzles arranged in the boundary area of the region are 216 nozzles from # 1080 to # 1296 in the region 1, and are 216 nozzles from # 1297 to # 1513 in the region 2. In this boundary area, recording is performed by applying different heater heating conditions to IDATA1 and IDATA2 processed by different masks. In the boundary area, there is a possibility that a color difference gap may occur. By processing in this way, in this embodiment, an image is formed in a gradation, and the color difference gap is relaxed.

  In addition, the evaluation result of the recording result by the above-described conventional method and the method of the present embodiment will be described. As an evaluation method, there is used a method in which the density and color difference of actually generated unevenness are reproduced by image editing software, and this is simulated on a display.

  As a result, in the case of the conventional method indicated by reference numeral 901, the boundary unevenness can be clearly perceived, but in the case of the method of the present embodiment indicated by reference numeral 902, the density gap is blurred and the unevenness is reduced. That is, it has been recognized that the method of the present embodiment has a sufficient effect for improving the image quality.

  Here, FIG. 9A shows the recording pattern of the attention area 903 shown in FIG. 8 in more detail. That is, in FIG. 9A, enlarged views of the areas 71, 72, and 73 in the area 1 shown in FIG. 8 are shown as areas 74 to 76, respectively.

  In the recorded image 74 in the boundary area shown as the first example, the pattern is not changed in the direction (hereinafter, referred to as vertical) orthogonal to the nozzle arrangement direction (hereinafter, referred to as horizontal). That is, the mask used at this time has a striped pattern along the heater arrangement direction. The size of this mask is horizontal 2592 (number of nozzles arranged) × vertical 1 nozzle, and the processing load of the recording apparatus 10 can be reduced.

  Further, in the recorded image 75 in the boundary area shown as the second example, the pattern in the oblique direction is repeated. That is, there is a pattern change in a direction (vertical) orthogonal to the nozzle arrangement direction (horizontal). The size of the mask used at this time is 2592 horizontal (the number of nozzles arranged) × 9 vertical nozzles, and the mask capacity is larger than that shown in the first example.

  The recorded image 76 in the boundary area shown as the third example has a distributed pattern. That is, the mask used at this time has a pattern in which recording pixels and non-printing pixels are dispersed in the heater arrangement direction. The size of the mask is further larger than that of the first and second examples described above, and becomes 2592 horizontal (the number of nozzles arranged) × 50 vertical nozzles.

  In terms of size, the processing load is lightest in the case of the mask used in the first example. On the other hand, in terms of blurring unevenness between adjacent regions and making it difficult to recognize the boundary region, the effect is the order of the mask of the first example <the mask of the second example <the mask of the third example. Will increase the effect.

  Here, three examples of the mask pattern and size have been described, but the present invention is not limited to this. The application range of the mask may be widened or conversely narrowed, the pattern may be changed, or the mask process may be changed for each recording head. Such a change can be considered appropriately by shifting the characteristics of the recording head, the number of nozzles, the color and type of ink, the characteristics, or the occurrence point of unevenness for each color, and so on.

  Further, as described above, when masking the recording data in the boundary area between the area 1 and the area 2, two types of masks for IDATA1 and IDATA2 are required. The reason why two types of masks are required is to generate the same number of sets of recording data (IDATA1, IDATA2) as the number of detection temperatures calculated from each region (two in this embodiment). .

  Here, FIG. 9B shows the correspondence between IDATA1 and IDATA2 and the recorded image.

  In the region of interest, there are a dark portion 77 and a thin portion 78. In this case, the dark portion 77 of the region corresponding to the nozzles # 1080 to # 1296 in region 1 is recorded based on IDATA1, and the light portion 78 is recorded based on IDATA2.

  In addition, the dark portion 77 of the region corresponding to the nozzles # 1297 to # 1513 in region 2 is recorded based on IDATA2, and the thin portion 78 is recorded based on IDATA1. Although not shown, the area corresponding to the nozzles # 1 to # 1079 in area 1 is recorded based on IDATA1, and the area corresponding to the nozzles # 1514 to # 2592 in area 2 is also based on IDATA1. Recorded.

  As described above, in the present embodiment, among image data corresponding to each area, image data used for recording a boundary area between adjacent areas (a predetermined range between areas) and image data other than the boundary area are recorded. The image data is processed using masks having different mask patterns.

  Next, an example of the configuration of the control system of the recording apparatus 10 shown in FIG. 1 will be described with reference to FIG.

  The configuration of the recording apparatus 10 is large, and is divided into a control unit 30 and a plurality of recording heads H. The control unit 30 is realized by, for example, a CPU, a RAM, a ROM, or an ASIC (Application Specific Integrated Circuit).

  Here, the control unit 30 includes a storage memory 31, a temperature information acquisition unit 32, a region temperature calculation unit 33, an image processing unit 34, a determination unit 35, and a head control unit 36.

  The storage memory 31 temporarily stores image data sent from the host device 24. The temperature information acquisition unit 32 acquires detection results of a plurality of temperature detection sensors in the recording head H. Based on the detection results of the plurality of temperature detection sensors acquired by the temperature information acquisition unit 32, the region temperature calculation unit 33 controls the control temperature representing each region in the recording head H and the boundary region between adjacent regions. Calculate the temperature.

  The image processing unit 34 performs a mask process or the like on the image data to generate a plurality of sets of recording data. In the image processing unit 34, for example, processing for converting the image data into the nozzle arrangement direction of the recording head is also performed.

  Based on the control temperature calculated by the region temperature calculation unit 33, the determination unit 35 determines the heating condition of the heater when performing a recording operation using each set of recording data. In the present embodiment, the heating condition of the heater refers to the energization time to the heater, but is not limited thereto. For example, the relationship between the length of the pre-pulse and the main pulse may be used as the heating condition.

  The head control unit 36 generates various signals based on the determination result by the determination unit 35 and controls the operation of the recording head H. That is, the head controller 36 performs a recording operation by transferring a set of recording data (IDATA1, IDATA2), a heat enable signal (HENB1, HENB2), a latch signal DLT, a recording clock signal DCLK, and the like toward the recording head H. Is controlled (recording control). In addition, the heating control to the heater is also performed by these various signals.

  Next, an example of a processing flow in the recording apparatus 10 will be described with reference to FIG. Here, the flow of processing when determining the heating condition of the heater will be described.

  First, when the recording operation is started, the recording apparatus 10 causes the control unit 30 to generate an interrupt process at a predetermined period (for example, a period of 10 ms) (after YES in S101, S102). That is, interrupt processing is started.

  In this process, first, the recording apparatus 10 acquires the detection value of each temperature detection sensor Di provided in the recording head H in the temperature information acquisition unit 32 (S103). Then, the region temperature calculation unit 33 calculates a temperature (control temperature) used for control based on the detected value (S104). For example, the set value of the control temperature for IDATA1 is calculated according to “Formula 2” for calculating the average temperature of each region described above. As the set value of the control temperature for IDATA2, the average temperature of the temperature detection sensor Di3 is calculated based on “Equation 1” as the temperature between the regions.

  Subsequently, in the recording device 10, the determination unit 35 refers to a heating condition table (not shown) based on the calculated control temperature (S105), and determines the heating condition of the corresponding heater. That is, the heater heating condition during recording based on IDATA1 and the heater heating condition during recording based on IDATA2 are determined (S106).

  In the description of FIG. 11, the heater heating condition is set (in-page PWM control) at predetermined intervals (for example, every 10 ms) during the recording operation, but is not limited thereto. For example, the heating condition may be changed between pages (PWM control between pages).

  Further, the set value of the control temperature for IDATA2 is not limited to the average temperature value of Di3, and other temperatures may be referred to. For example, the difference between the detected temperature of the temperature detection sensor Di3 and the average temperature of the region 2 is obtained, and when the detected temperature of the temperature detection sensor Di3 is higher than the average temperature of the region 2, the difference in temperature is detected by the temperature detection sensor Di3. The value is added. Further, when the temperature detected by the temperature detection sensor Di3 is lower than the average temperature in the region 2, a value obtained by subtracting the temperature difference from the temperature detected by the temperature detection sensor Di3 may be used. Further, as described in JP-A-5-31916 and JP-A-5-208505, even if there is no temperature detection sensor, the current temperature is calculated and the heating condition is determined by the calculation result. Also good.

  As described above, according to the present embodiment, a plurality of temperature information is calculated corresponding to each region, and the image data corresponding to each region is masked to set a plurality of recording data (for each region). A set of recording data equal to the temperature information) is generated. Then, based on the plurality of temperature information calculated corresponding to each region, the heating condition of the heater (the energization time to the heater) when performing the recording operation using each of the plurality of sets of recording data in the corresponding region ).

  That is, in the configuration in which recording is performed by switching the heating condition of the heater in units of heater groups (heat generating element groups) divided into a plurality of areas, it is possible to suppress the occurrence of unevenness in the boundary areas of the areas. Thereby, the recording image quality can be improved as compared with the conventional configuration.

  The above is an example of a typical embodiment of the present invention, but the present invention is not limited to the embodiment described above and shown in the drawings, and can be appropriately modified and implemented without departing from the scope of the present invention. .

  For example, in the above description, the case where the inside of the recording head is divided into two regions has been described. However, the present invention is not limited to this and may be divided into three or more regions. For example, FIG. 12 shows a recording head 121 divided into two areas, a recording head 122 divided into three areas, and a recording head 123 divided into four areas. As compared with the recording head 121, the number of nozzles of the recording heads 122 and 123 is increased in the nozzle arrangement direction, and the number of regions is increased accordingly.

  In the case of the recording heads 122 and 123, an area where unevenness may occur is larger than that of the recording head 121. In this case, as shown in FIG. 5B, a recording head capable of setting the heating conditions of the three systems of heaters and a mask pattern corresponding to IDATA1 to 3 are used. In this way, it is possible to cope with unevenness occurring in each boundary area by the same processing as described above. That is, even when the length of the recording head is further increased and the number of nozzles is increased and the number of regions is increased accordingly, the processing of the above embodiment can be applied.

  In the above description, the recording apparatus employing the full line type recording head has been described as an example, but the present invention is not limited thereto. That is, any recording apparatus having a recording head that performs recording by switching the heating condition of the heater in units of heater groups (heat generating element groups) divided into a plurality of regions may be used.

Claims (7)

A recording head having a plurality of heating elements that generate thermal energy for discharging ink from the discharge ports is arranged, and a heating element group divided into a plurality of regions along the arrangement direction of the heating elements as a unit A recording apparatus for recording an image by switching heating conditions of a heating element,
Calculating means for calculating a plurality of temperature information corresponding to each region based on detection values from a plurality of temperature detecting elements arranged in the recording head along the arrangement direction of the plurality of heating elements;
Using a mask for generating a set of recording data of the same number as a plurality of temperature information calculated from each region, a plurality of recordings corresponding to each region are performed by masking image data corresponding to each region. Image processing means for generating a set of data;
Determination to determine a heating condition of the heating element when performing a recording operation using each of the plurality of sets of recording data in the corresponding area based on the plurality of temperature information calculated corresponding to each area Means,
Based on a set of a plurality of recording data corresponding to each region, by performing heating control according to the heating condition determined by the determining means for the corresponding heating element, from the ejection openings arranged in the recording head And a recording control means for recording an image by ejecting ink. The calculating means includes
The temperature information representative of each region and the temperature information of the boundary region between adjacent regions are calculated for each region based on detection values from the plurality of temperature detection elements. Recording device. The image processing means includes
Image data corresponding to each area is processed using a mask having a different mask pattern for image data used for recording a boundary area between adjacent areas and image data other than the boundary area. The recording apparatus according to claim 1 or 2. The mask pattern for the image data used for recording the boundary area is:
A striped pattern along the arrangement direction of the heating elements,
A repeating pattern in an oblique direction with respect to the arrangement direction of the heating elements,
The recording apparatus according to claim 3, wherein the recording pixel is any one of a pattern in which recording pixels and non-recording pixels are dispersed in the arrangement direction of the heating elements. The determining means includes
The recording apparatus according to any one of claims 1 to 4, wherein the heating condition is determined by energizing time to the heat generating element during a recording operation. The recording head is
A plurality of heating elements are arranged in the arrangement direction of the heating elements so as to cover the recording width of the recording medium,
The recording control means includes
6. An image is recorded by ejecting ink from ejection ports arranged in the recording head while conveying a recording medium in a direction crossing the arrangement direction of the heat generating elements. The recording apparatus according to item 1. A recording head having a plurality of heating elements that generate thermal energy for discharging ink from the discharge ports is arranged, and a heating element group divided into a plurality of regions along the arrangement direction of the heating elements as a unit A processing method of a recording apparatus for recording an image by switching heating conditions of a heating element,
A step of calculating a plurality of temperature information corresponding to each region based on detection values from a plurality of temperature detection elements arranged in the recording head along an arrangement direction of the plurality of heating elements;
The image processing means masks image data corresponding to each area by using a mask for generating a set of recording data of the same number as the number of pieces of temperature information calculated from each area. Generating a plurality of corresponding sets of recorded data;
Based on the plurality of temperature information calculated corresponding to each region, the determining unit performs heating operation of the heating element when performing a recording operation using each of the plurality of recording data sets in the corresponding region. A step of determining
The recording control means is arranged in the recording head by performing heating control according to the heating condition determined by the determining means for the corresponding heating element based on a set of a plurality of recording data corresponding to each area. And a step of recording an image by discharging ink from the discharged discharge port.