Abstract: A piezoelectric actuator includes piezoelectric layers. Individual electrodes are formed on an outermost piezoelectric layer and arranged in a row extending along a first direction. Through holes are formed in the outermost piezoelectric layer and arranged substantially in a row extending in the first direction to contact with first end portions of the individual electrodes. The individual electrodes include at least one first individual electrode and at least one second individual electrode. The first individual electrode comprises a first electrode terminal provided at the first end portion, and the second individual electrode comprises a second electrode terminal provided at a second end portion opposite to the first end portion with respect to a second direction perpendicular to the first direction. The second individual electrode has a thickened portion extending from the second electrode terminal towards the first end portion.

Abstract: Liquid ejecting apparatuses and image formed methods are provided. In an exemplary embodiment, a liquid ejecting apparatus is provided including a head unit, a movement mechanism, and a control section. The head unit has along a first direction a plurality of heads, in which a plurality of nozzles that eject a liquid onto a medium are lined up in the first direction, and the head unit forms a single raster line by ejecting the liquid while performing m number of movements relative to the medium in a second direction, which intersects the first direction. The movement mechanism causes the head unit to perform a plurality of movements relative to the medium alternately in the second direction and the first direction. The control section forms an image having a resolution that is n times a pitch of the nozzles.

Abstract: The recording head is formed with ejection holes including first ejection holes and second ejection holes arranged in a first direction. A recording medium has invisible columns extending in the first direction and invisible rows extending in a second direction orthogonal to the first direction. The invisible columns have first invisible columns and second invisible columns alternately arranged in the second direction. The scanning unit performs a first scan and a second scan in the second direction. The controller prevents the recording head in the first scan from ejecting ink droplets from the first ejection holes onto the first invisible columns and from the second ejection holes onto the second invisible columns, and prevents the recording head in the second scan from ejecting ink droplets from the first ejection holes onto the second invisible columns and from the second ejection holes at the first invisible columns.

Abstract: The present disclosure relates to a fast drying solvent-based inkjet ink composition for thermal inkjet printing, the ink composition comprising at least 40 weight percent base solvent, a solvent-compatible colorant, not more than 25 weight percent propellant, a decap controlling additive, and not more than 5 weight percent water. The present disclosure also relates to the method and system for inkjet printing with the above-described ink.

Abstract: A method of discharging droplets includes discharging a liquid material from a droplet discharge head and causing the droplet discharge head and a substrate as a landing target for the liquid material to move relative to each other to thereby deposit the liquid material on the substrate, feeding and removing the substrate to and from a droplet discharge apparatus provided with the droplet discharge head, performing a weight measurement discharge from the droplet discharge head substantially concurrent to the feeding and removing of the substrate to and from the droplet discharge apparatus, and measuring the weight of the liquid material discharged in the weight measurement discharge.

Abstract: A printing apparatus includes a printing unit for printing visual information on a non-recording surface of a rotatably driven recording medium by discharging ink droplets. A control unit controls movement of the printing unit in a radial direction of the recording medium, and discharge timing of the ink droplets. The printing unit prints the visual information by multi-path printing by printing on a same radius position of the non-recording surface by discharging ink from different ink discharge nozzles. The control unit controls the printing unit so as to print with a first printing pattern having a first number of paths and a second printing pattern having a second number of paths. The first printing pattern is used on other locations of the non-recording surface and the second printing pattern is used when printing on an innermost periphery region of the non-recording surface.

Abstract: An image forming apparatus which forms a halftone image on a print medium by using a multipass process to scan a printhead N (N is an integer of 2 or more) times in a single area on the print medium and form dots by each scan operation includes a pass division unit which sets the print density of a scan operation in the first pass so as to prevent dots from overlapping with each other on the print medium, and sets the print densities of scan operations in the second to Nth passes, a tone reduction unit which generates print data of the respective scan operations in accordance with the print densities set by the pass division unit, and a printhead which prints a halftone image on a print medium on the basis of the print data generated by the tone reduction unit.

Abstract: A disclosed laminate structure is capable of having its surface free energy changed with a small amount of UV irradiation. The invention also discloses a method of manufacturing the laminate structure; an electronic device having the laminate structure; an electronic device array having a plurality of the electronic devices; and a display apparatus having the electronic device array. The laminate structure includes a substrate 11, a wettability variable layer 12 disposed on the substrate, and a conducting layer 13 patterned on the wettability variable layer 12. The wettability variable layer 12 includes a material whose critical surface tension varies upon application of energy. The material with variable critical surface tension has a main chain and a side chain. The side chain has two or more sites of which the bond is cleaved upon absorption of energy.

Abstract: A liquid ejection control device controlling a liquid ejecting mechanism having a plurality of liquid ejection heads, includes a dividing unit to which image data consisting of a plurality of pixels is inputted and which divides the image data into a plurality of pieces of divided image data, each corresponding to pixels which undergo a liquid ejection, of each of the liquid ejection heads, a correction data acquiring unit which acquires correction data eliminating a deviation of liquid ejection locations of the plurality of liquid ejection heads, a correcting unit which corrects the divided image data on the basis of the correction data, and a liquid ejection controlling unit which performs liquid ejection control by which each of the liquid ejection heads is driven on the basis of the divided image data which is corrected.

Abstract: A recording apparatus for recording an image on a recording medium by scanning the recording medium with a recording head for discharging ink includes a thinning unit configured to thin data for discharging ink by the recording head on a plurality of areas formed by dividing scanning regions including at least a first scanning region and a second scanning region to be recorded each by one scan of the recording head in the scan direction, and a recording head drive unit configured to discharge ink by driving the recording head based on data which has been thinned by the thinning unit, wherein a boundary between the areas in the first scanning region is located in a different position from that of a boundary between areas in the second scanning region, which is adjacent to the first scanning region, in the scan direction.

Abstract: This invention provides a system and method for printing continuous web and feeding ink to printing pens (or cartridges) that employs an array of interleaved ink-jet pens that are arranged to receive bulk ink through a manifold. The manifold and pens are mounted on a fixed array suspended over the web feed path. The manifold includes a plurality of self-sealing quick-disconnect couplings that each serve a discrete ink-jet pen. The pens lay down ink in a registered manner across the full width of the web. The pens are organized into two parallel, multi-pen arrays that are each diagonally oriented with respect to the feed direction. The feed path allows for duplex printing with a second web-side's array located on a lower level of the device, generally beneath the first-side's array. Duplex printing is facilitated due to its inherent length of the feed path. The printed part of the web is free of contact over predetermined lengths that ensure sufficient time for the drying of ink.

Abstract: A printer including a feeding unit configured to perform repeated feeding of a medium for a predetermined feeding distance in a predetermined feeding direction, a print head configured to print on a printing surface of the medium in a printing zone set each time the feeding unit performs a feeding of the medium for the feeding distance, and a printing pass setting unit configured to set the printing zone containing a plurality of printing passes. The printing pass setting unit sets the printing passes such that boundaries between the printing passes extend diagonally relative to a width direction of the medium that is perpendicular to the feeding direction. The printing pass setting unit can set the printing passes such that the boundaries between the printing passes extend in waveform in the width direction with oscillation of the waveform being in the feeding direction.

Abstract: A printer controller for controlling a printhead comprising at least one monolithic printhead module, the at least one printhead module having a plurality of rows of nozzles configured to extend, in use, across at least part of a printable pagewidth of the printhead, the nozzles in each row being grouped into at least first and second fire groups, the printhead module being configured to sequentially fire, for each row, the nozzles of each fire group, such that each nozzle in the sequence from each fire group is fired simultaneously with respective corresponding nozzles in the sequence in the other fire groups, wherein the nozzles are fired row by row such that the nozzles of each row are all fired before the nozzles of each subsequent row, wherein the printer controller is configured to provide one or more control signals that control the order of firing of the nozzles.

Abstract: A data processing apparatus includes a mask processor for performing a mask process for binary data, which is obtained by a binarization process using a dot arrangement pattern, by using mask patterns having print permitting pixels to generate binary data used for each of a plurality of scans of a print head to a same area of a print medium. An arrangement pattern of pixels that correspond to both of first data representing the print permitting pixels in at least one of the mask patterns and second data representing pixels to which dots are printed in the dot arrangement pattern satisfies the characteristics of (a) power spectrums of a low frequency region are smaller than power spectrums of a high frequency region, and (b) a peak of the power spectrums does not exist in a region lower side of half of the low frequency region.

Abstract: An object of the present invention is to provide an ink jet printing apparatus and an ink jet printing method which can inhibit degradation of image quality resulting from ink drying unevenness regardless of the type of ink and the amount of ejected ink. To accomplish the object, the present invention determines, based on print data, drying characteristics of ink applied by a print head to a predetermined time control area in an image forming area to be formed on a print medium. Based on the result of the determination, a wait time is controlled which is set between a preceding scan and a succeeding scan in a plurality of scans performed within the wait time control area.

Abstract: A method of printing from a printhead includes virtually dividing a nozzle array of the printhead into first and second nozzle sections. N print masks associated with the first and second nozzle sections govern the deposition of ink drops on a print medium. The N print masks are associated with one swath and are defined as a mask grid. The mask grid is arranged as a series of vertically extending adjacent mask columns and a series of horizontally extending mask rows. The vertically extending mask columns comprise enabling mask columns comprising first mask elements and disabling mask columns consisting essentially of second mask elements. The N print masks are associated with the first and second nozzle sections for printing an input image. Each print mask is defined as a mask grid arranged in an N series of vertically extending adjacent mask columns and a series of Z horizontally extending mask rows.

Abstract: Systems and methods are provided for calibrating a sensory array to ensure a robust cross-process registration measurement. The calibration is implemented using a calibration step that determines the signature error amount of a given image reading sensor. The signature error amount for the sensor is stored in a signature error look-up table. When the sensors are used to sense print head alignment, the correction may be implemented by accessing the signature error look-up table for the given sensor when calibrating the print heads. The signature error look-up table provides an amount of offset for each sensor that is used in determining the appropriate head position of a given print head to calibrate the print heads for the signature error associated with the given sensor.

Abstract: A method for forming an image on recording media includes providing a support adapted to receive the recording media; providing a controller programmed for controlling a print head comprising a plurality of individually controllable marking elements to form the image on the recording media in accordance with image data corresponding to the image; and operating the print head to form a plurality of sub-images on the recording media, wherein the plurality of sub-images are stitched together to form the image with a stitching pattern that is determined based at least one a size of a portion of a feature of the image that can be formed in each sub-image of the plurality of sub-images.

Abstract: In a printer, a first section is sized to accommodate a rolled sheet therein. A printing head is horizontally movable along a moving path extending in a first direction and operable to perform printing on a part of the rolled sheet which is drawn out from the first section. A second section is provided on a first side of the first section relative to the first direction. A third section is provided on a second side of the first section relative to the first direction opposite to the first side. A control board on which a circuit operable to control an operation of the printer is mounted is disposed in the first section so as to extend vertically. An ink supplying member is disposed in the third section that supplies ink to the printing head. The moving path is longer than a dimension of the first section in the first direction.

Abstract: The printing elements of each printing element array are divided into blocks. A block to be driven and a block not to be driven are determined for each scanning of a printhead. The printhead is driven to print by complementing blocks to be driven by each scanning in a plurality of scanning operations. In each scanning, the printhead prints while making a printing area corresponding to at least one ink different from a printing area corresponding to another ink.

Abstract: This invention provides a printing apparatus that performs printing on a print medium. The printing apparatus includes: a dot data generator that performs a halftone process on image data, wherein the print image is formed by mutually combining print pixels belonging to each of a plurality of pixel position groups for which a physical difference is assumed at a formation of dots by the print image generator, in a common print area, and the halftone process is configured to determine the status of dot formation on each of the print pixels on an assumption of the physical difference.

Abstract: A liquid droplet-discharging device comprises: a droplet-discharging head having a plurality of nozzles that are arranged in a predetermined direction and discharge liquid droplets; a scanning unit for relatively moving the droplet-discharging head and a substrate toward a scanning direction: a memory memorizing pattern data corresponding to driving nozzles that are selected from the plurality of nozzles in each of a plurality of discharged regions, by partitioning a drew region of the substrate into the plurality of discharged regions every discharging frequency along a scanning direction of the substrate; a transferring unit for developing the patterned data memorized by the memory into a plurality of data to be divided and transferring the divided data to the liquid droplet-discharging head in order; and an output unit for outputting a driving signal that drives a driving nozzle selected by the divided data to discharge the liquid droplets.

Abstract: In a configuration in which a printhead including a plurality of first printing elements for discharging ink droplets and a plurality of second printing elements for discharging ink droplets larger than ink droplets discharged by the first printing elements is used, the first and second plurality of printing elements are divided into multiple blocks in such a manner that the first printing elements belong to one block and the second printing elements belong to another block. The blocks are individually driven in a time-divisional manner. In the time-divisional driving, the block consisting of the plurality of first printing elements is driven first and then the block consisting of the second printing elements is driven.

Abstract: A liquid ejecting apparatus includes: a printing head that ejects liquid to form dots on a recording medium; a head driving section that performs a main scanning for the printing head; a transporting section that performs a sub-scanning for the recording medium; an image forming section that forms an image, a first dot formation area and a second dot formation area; an overlap control section that performs overlap control for intermittently forming dots on the first and second dot formation areas so as to make the second dot formation area overlap with the first dot formation area and fill spaces between the dots intermittently formed on the first dot formation area; and a cancellation section that cancel the overlap control when a blank area exists in an image and a nozzle forming at least one of the first dot formation area and the second dot formation area.

Abstract: In the case where a multipass printing and an interlace printing are used together, the present invention enables outputting an image of good quality independently of the relation between the number of passes in the multipass printing and increase in the resolution in the sub-scanning direction through the interlace printing. Data processing is executed while pixels of inputted image data are made to correspond to two or more rasters in the sub-scanning direction, so that the dots are arranged in these rasters at a substantially equal rate, in the case where the number of print scannings to be executed multiple times is not an integral multiple of the number of rasters.

Abstract: A handheld printer that provides an appropriate application of ink to a print medium without a bulky and complex mechanical system for positioning a print head with respect to the print medium. A handheld printer according to the present teachings includes a navigation subsystem that tracks a motion of the handheld printer with respect to a printing surface and a print head controller that causes a print head to fire ink drops onto the printing surface in response to the motion and in response to an image contained in an image buffer.

Abstract: A method of forming a hydrophobic coating layer on a surface of a nozzle plate of an inkjet printhead includes forming a plurality of nozzles in the nozzle plate, each of the nozzles having an exit, stacking a film on the surface of the nozzle plate to cover the exit of each of the nozzles, forming a predetermined metal layer on an inner wall of each of the nozzles and an inner surface of the film covering the exit of each of the nozzles using a plating method, removing the film from the surface of the nozzle plate, forming a hydrophobic coating layer on the surface of the nozzle plate to cover the metal layer exposed through the exit of each of the nozzles, and removing the metal layer formed on the inner wall of each of the nozzles and the hydrophobic coating layer formed on the surface of the metal layer.

Abstract: A piezoelectric actuator includes a first ceramic sheet having individual inner-electrodes formed thereon, a second ceramic sheet having a common inner-electrode formed thereon, a third ceramic sheet having individual surface-electrodes formed thereon, and a fourth ceramic sheet having a plurality of connection electrodes connecting the individual surface-electrodes and the individual inner-electrodes respectively. The connection electrodes have first portions, second portions and third portions respectively, the first portions facing the individual surface-electrodes and arranged at a pitch in a row in a row-direction, the second portions facing the individual inner-electrodes and being arranged in the row-direction to be shifted with respect to the first portions by half the pitch respectively; and the third portions connecting the first portions and the second portions respectively.

Abstract: A liquid ejecting apparatus including a head unit that has a plurality of heads along a first direction, in which a plurality of nozzles that eject a liquid onto a medium are lined up in the first direction, and that ejects the liquid while moving relative to the medium in a second direction, which intersects the first direction, the head unit having a width in the first direction that is greater than a width of a medium in the first direction, a movement mechanism that makes the head unit move relative to the medium a plurality of times alternately in the second direction and the first direction, and a control section that forms a raster line group by forming each raster line.

Abstract: The print permitting ratios of the masks in the first to fourth passes of a C ink are respectively 6.2%, 37.5%, 37.5%, and 18.8%. On the other hand, the print permitting ratios of the masks in the first to fourth passes of an M ink are respectively 12.5%, 37.5%, 37.5%, and 12.5%. In this way, the respective masks are set such that a larger amount of the C ink is applied in a later pass as compared with the M ink. Thereby, it is possible to reduce an amount of the M ink to be applied later with respect to the C ink functioning to “reduce a permeation speed of an ink applied later by filling,” and it is possible to prevent a permeation speed from slowing down overall. As a result, it is possible to prevent the occurrence of beading due to a time to complete permeation becoming longer.

Abstract: A method for ink jet printing includes moving one or more receivers along a printing pass, ejecting ink drops from a first ink jet print head on a first receiver region of the one or more receivers in the printing pass, ejecting ink drops from a second ink jet print head on a second receiver region of the one or more receivers in the printing pass, and providing maintenance to the first ink jet print head while the second ink jet print head ejects ink drops on the first receiver region or the second receiver region.

Abstract: A print engine is provided which has a printhead capable of printing a maximum of n channels of print data and a controller. Each channel is associated with rows of printing nozzles of the printhead. The controller controls the printhead to print in: a first mode, in which the printhead receives from the controller, print data for a first number of the channels; and a second mode, in which the printhead receives from the controller, print data for a second number of the channels less than the first number and dummy data for a portion of each nozzle row associated with the remaining number of the channels. The first number is less than n.

Abstract: A printhead is provided having a plurality of nozzle rows which have displaced row portions. The displaced row portions of at least some of the rows are different in length than the displaced row portions of at least some of the other rows.

Abstract: A printing method includes: preparing a printing apparatus provided with a carry unit that carries a medium in a carrying direction, and a plurality of nozzle groups that have respectively a plurality of nozzles lined up in the carrying direction; and printing an image to be printed on the medium by alternately repeating a dot forming process for forming dots on the medium by ejecting ink from each nozzle of a plurality of the nozzle groups that move in a moving direction, and a carrying process for carrying the medium in the carrying direction, and forming a plurality of rows of dots, lined up in the carrying direction, that are configured by a plurality of dots lined up in the moving direction, wherein in a case a certain row of dots is formed by a plurality of the nozzles, if, of a plurality of the nozzles that form the certain row of dots, the number of nozzles of a certain nozzle group is smaller than, of a plurality of the nozzles that form the certain row of dots, the number of nozzles of another nozzl

Abstract: Mask patterns to be used for multi-pass printing make it possible to make a print with a higher quality at a higher speed. Specifically, by performing a swapping process with adjacency forbiddance, two points in the horizontal direction, or the scanning direction of a printing head, are selected in a buffer in which codes for each scan pass are set depending on printing ratios of a gradation mask. Subsequently, codes are swapped between the two points. By this swap, adjacencies between print permitting areas are eliminated in the mask pattern. As a result, when driving frequencies set for the printing head is kept constant, the scanning speed can be doubled at minimum.

Abstract: An ink jet recording head includes at least three nozzle array groups, each including at least two nozzle arrays with an ink supply port interposed therebetween and each ejecting a different ink. Opening areas of the ejection outlets of the nozzle arrays in each array group are of different sizes. Two adjacent nozzle array groups each include three nozzle arrays. The nozzle array group not identified as one of the two adjacent nozzle array groups is supplied with ink having a highest lightness among the three kinds of inks.

Abstract: An image forming apparatus which forms a halftone image on a print medium (200) using multipass processing of reciprocally scanning a single area by an inkjet head (220) a plurality of number of times, forming dots in one of reciprocal scan operations, and moving the inkjet head (220) to a home position in the other reciprocal scan operation includes a print data generation unit (370) which generates print data of each print-scan operation, a printer engine (180) which prints a halftone image on the basis of the print data generated by the print data generation unit (370), and a sensor (230) which detects the state of printing in up to a print-scan operation immediately preceding a print-scan operation of interest. The print data generation unit (370) corrects print data in synchronism with printing by the printer engine (180) on the basis of the detected printing state.

Abstract: An imaging device includes an image receiving surface configured to move in a process direction in the imaging device. A plurality of printhead arrays are arranged to deposit marking material onto the image receiving surface. Each printhead array includes a plurality of printheads arrayed in a cross-process direction across the image receiving surface. Each printhead array includes at least one stitch line corresponding to a position along an axis parallel to the cross-process direction where an end of one printhead in the printhead array aligns with an end of another printhead in the printhead array. The at least one stitch line of each printhead array is offset a predetermined distance in the cross-process direction from the at least one stitch line of each of the other printhead arrays.

Abstract: The first plurality of nozzles and the second plurality of nozzles in a fluid ejection system are arranged in a plurality of nozzle pairs, each nozzle pair of the plurality of nozzle pairs including a first nozzle from the first plurality of nozzles and an associated second nozzle from the second plurality of nozzles, the first nozzle and associated second nozzle of each nozzle pair spaced apart in a second direction perpendicular to a first direction, the first direction being the direction of movement of a print media, by greater than zero and less than the pixel pitch p and spaced apart in the first direction. A controller is configured to cause the first nozzle and the second nozzle of each nozzle pair to deposit droplets at the same pixel in a line of pixels.

Abstract: A liquid ejecting method according to the present invention includes the following: varying dots that are to constitute a dot row that is to be formed with a first nozzle row and a second nozzle row, according to a usage rate of each of the first and second nozzle rows when forming that dot row, the first nozzle row including a plurality of first nozzles lined up in a transport direction, the second nozzle row including a plurality of second nozzles in the transport direction, the first nozzles of the first nozzle row forming dots on a medium by ejecting liquid while moving in a movement direction, the second nozzles of the second nozzle row forming dots on the medium by ejecting liquid while moving in the movement direction, the dot row that has been formed on the medium being composed of a plurality of the dots to be lined up on the medium in the movement direction; and forming a plurality of the dot rows in the transport direction by alternately repeating a transport operation of transporting the medium in

Abstract: This specification discloses a computer program product manufacturing method. This method is provided with a forming step, a combining step, and a storing step. The forming step instructs the printer to form a dot at a predetermined coordinate. The combining step creates a combination of the predetermined coordinate and a sub-coordinate which is different from the predetermined coordinate. A distance between the predetermined coordinate and a position of a dot formed when the printer tries to form the dot at the sub-coordinate is shorter than the distance between the predetermined coordinate and the position of the dot formed in the forming step. A storing step stores a computer program into a memory medium. The computer program includes instructions for ordering the computer device to perform a choosing step and a converting step. The choosing step chooses a coordinate from bit-mapped data.

Abstract: By suppressing deviation of dot-formation positions stemming from insufficient accuracy in conveying a printing medium due to eccentricity of a conveying roller, a printed image in which unevenness is less visible is obtained. An accumulated amount of conveyance errors is decreased by narrowing a nozzle-use range and reducing a conveyance amount over an entire printing region according to a mode used for printing an image in which the coverage of a printing medium is low due to a small number of ink colors to be used, for example, a mode used for printing a monochrome image by using a black ink dominantly in all of the density regions.

Abstract: A method of manufacturing an electrooptical device includes forming a film-deposited section of function liquid droplets on a substrate by a liquid droplet ejection apparatus having a plurality of color-dependent function liquid droplet ejection heads are arranged such that a plurality of color-dependent partial imaging lines, each formed by a plurality of ejection nozzles, are formed so as to continuously make up a single imaging line in the Y-axis direction. An imaging process is performed by repeating a main scanning operation for driving each function liquid droplet ejection head in synchronization with moving of the substrate in the X-axis direction, and a sub-scanning operation for moving the function liquid droplet ejection heads through a carriage unit in the Y-axis direction by a length of a partial imaging line.

Abstract: The image forming method for forming an image on a recording medium, wherein the image is divided into a plurality of regions, the method comprising: a droplet deposition rate calculation step; a dot arrangement specification step of specifying a dot arrangement pattern from the droplet deposition rate; and a droplet deposition control step of controlling droplet deposition operation in such a manner that the dot arrangement pattern specified in the dot arrangement specification step is achieved, wherein, in at least one of the plurality of the regions where the droplet deposition rate is lower than a maximum droplet deposition rate and is higher than a prescribed reference value, a dot line in a main scanning direction substantially perpendicular to the relative conveyance direction is formed in which the dots are continuously aligned so as to mutually overlap by a prescribed overlap ratio, in accordance with the droplet deposition rate.

Abstract: A method for reducing banding artifacts in a printed image, including irregularly advancing a media that will be printed upon while employing an entire single mask for marking elements of a printhead; and calculating a difference between an irregular advance amount of the media versus a nominal advance amount of the media. Finally, the single mask is nonuniformly circulated by the difference calculated in order to compensate for the media being irregularly advanced.

Abstract: A method for printing input digital images using an inkjet printing system having a first and second drop ejector arrays for ejecting drops of a particular ink, wherein ink paths supplying drop ejector arrays have different length projections. The method comprising printing a first combined number of ink dots using the first and second drop ejector arrays during first and third time intervals where the printhead is accelerating and decelerating; and printing a second combined number of ink dots using the first and second drop ejector arrays during a second time interval where the printhead is moving at a substantially constant velocity, wherein the percentage of ink dots that are printed by the drop ejector array having a longer length projection is less than 40% of the corresponding combined number of ink dots in at least one of the first or third time intervals.

Abstract: In an ink jet printing apparatus using many types of inks to execute bidirectional printing, when symmetrically arranged ejection opening rows for a cyan, magenta, and yellow inks are used in the print head, one-pass bidirectional printing is executed. On the other hand, if ejection opening rows for a black ink are used in addition to the above ejection opening rows, multi-pass printing is executed so that there are a number of dots formed with one application order for the black and other color inks and the same number of dots formed with another application order for the black and other color inks. This reduces the non-uniformity of the colors attributed to the difference in application order.

Abstract: A head adjustment method of adjusting overlaps of a plurality of print heads, which are arranged in a widthwise direction of a print medium in an image forming apparatus, in the widthwise direction. The head adjustment method includes setting a theoretical input pattern image to be formed by the print heads, outputting a practical output pattern image on the print medium by driving the print heads according to the input pattern image, estimating practical overlap values of the print heads through the output pattern image, and adjusting degrees of overlap between the print heads according to the estimated overlap values.

Abstract: Printheads configured to operate in accordance with a plurality of print modes. For example, one of the plurality of print modes can be selected in accordance with a bit of address data received by the printhead. In an exemplary embodiment, the selection of print mode can be accomplished by switching one or more actuator (e.g., heater) circuit addresses on the printhead.

Abstract: A recording head is operable to eject ink toward a recording medium. A carriage mounting the recording head is operable to carry the recording head in a first direction. At least one infrared ray heater is provided on the carriage so as to oppose the recording medium. An input energy of the infrared ray heater is 60 W or less.