Abstract: An inkjet apparatus for depositing liquid crystal according to an exemplary embodiment of the present invention includes: an inkjet head configured to discharge liquid crystal; a liquid crystal reservoir configured to provide the liquid crystal to the inkjet head, and the liquid crystal reservoir comprises metal; a storing tank configured to supply the liquid crystal to the liquid crystal reservoir; and a heat supply device configured to supply heat to the liquid crystal reservoir, in which a separation part is disposed inside of the liquid crystal reservoir, and the separation part divides the liquid crystal reservoir into an upper storing space and a lower storing space.

Abstract: A method performed by a printing system is described herein. A request is provided to a user to enter data related to print quality of a mark or marks printed on a portion of a background region. The background region includes an area or areas treated with a fixer fluid applied by a printhead. A user input is received associated to the request. A misalignment of the printhead is estimated in accordance with the user input. A printing system and a tangible machine readable storage medium are also described herein.

Abstract: A liquid discharge apparatus which causes a liquid to be discharged through a first nozzle by applying a driving signal to a first driving element, and causes a liquid to be discharged through a second nozzle by applying the driving signal to a second driving element, and which, with respect to the first nozzle, determines on the basis of an image formed by causing the liquid to be discharged through the first nozzle whether or not the first nozzle causes a liquid discharge failure, and, with respect to the second nozzle, determines on the basis of a detection signal which is obtained by applying the driving signal to the second driving element whether or not the second nozzle corresponding to the second driving element causes a liquid discharge failure.

Abstract: A method for determining an issue with an inkjet nozzle using an impedance difference includes taking a first impedance measurement with a sensor to detect a drive bubble in an ink chamber after a drive bubble formation mechanism is activated; and subtracting the first impedance measurement from a reference.

Abstract: In one example, a first swath is caused to be printed by a print unit on a media. The media is advanced with respect to the print unit. For a nominal second swath to be printed to beneath and adjacent to the first swath, a plurality of adjustment regions along the width of the nominal second swath are determined in accordance with a profile of non-constant advance errors for the media. An adjusted second swath is formed by, for each of the regions, adjusting the height of the nominal second swath in memory based on the determined amount of advancement error for the region. The print unit is caused to print the adjusted second swath on the media.

Abstract: An image forming apparatus which includes a head for discharging colored radiation curable ink and colorless radiation curable ink that are cured upon irradiation with electromagnetic waves onto a medium, and a controller for causing dots of the colored radiation curable ink and dots of the colorless radiation curable ink to be densely arranged.

Abstract: A method including acquiring a first deviation value of ink landing positions in each position in a first range from a first pattern printed over the first range of a recording sheet in a scanning direction at a first moving velocity of an inkjet head, acquiring variation information representing a variation in the scanning direction of the first deviation value, acquiring from the variation information a first representative value representing the first deviation value in the first range, acquiring a second deviation value from a second pattern printed over a second range included in the first range at a second moving velocity of the inkjet head, acquiring a second representative value representing a deviation value in the first range at the second moving velocity, based on the second deviation value and a difference between the first representative value and the first deviation value in the second range.

Abstract: A fluid ejection device includes: a modulator adapted to pulse-modulate a drive waveform signal forming a basis of a drive signal of an actuator to obtain a modulated signal; a digital power amplifier circuit adapted to power-amplify the modulated signal to obtain a power-amplified modulated signal; a low pass filter adapted to smooth the power-amplified modulated signal to obtain the drive signal; and a power amplification stopping section operating when holding a voltage of the actuator constant.

Abstract: An apparatus enables a printer to identify neighboring inkjets to compensate for inoperative inkjets with reference to different search patterns. The apparatus includes a plurality of mutliplexers, a memory, a decoder, and a controller. The multiplexers are operatively connected to the memory to receive data that selects one of a plurality of image data pixels on the inputs of the multiplexers. The outputs of the multiplexers are concatenated in a predetermined order and the decoder identifies a highest priority image data pixel available for inoperative inkjet compensation. The controller operates the memory to output the data stored at the plurality of storage locations in a first sequence to enable the multiplexers to output the image data pixels in the predetermined order for the decoder.

Abstract: The invention provides apparatuses and methods for acoustically ejecting the fluid from a reservoir contained in or disposed on a substrate. The reservoir has a portion adapted to contain a fluid, and an acoustic radiation generator is positioned in acoustic coupling relationship to the reservoir. Acoustic radiation generated by the acoustic radiation generator is transmitted through at least the portion of the reservoir to an analyzer. The analyzer is capable of determining the energy level of the transmitted acoustic radiation and raising the energy level of subsequent poises to a level sufficient to eject fluid droplets from the reservoir. The invention is particularly suited for delivering fluid from a plurality of reservoirs in an accurate and efficient manner.

Abstract: A system and method of printing includes providing print and non-print drop formation waveforms to a drop formation device of a drop ejector in response to input print data to form print and non-print drops, respectively, from a liquid jet. First and second charging waveforms are provided to a charging electrode of a drop charging device when a relative motion of a receiver and the drop ejector is provided or measured at first and second speeds, respectively. The first and second charging waveforms are independent of input print data and include first and second voltage states. The drop formation device and the drop charging device are synchronized to produce print and non-print drop charge states on print and non-print drops, respectively. A deflection device causes print and non-print drops to travel along print and non-print drop paths, respectively, with the non-print drops being collected by a catcher.

Abstract: A printing apparatus comprising: a first transport unit that transports a printing medium; a line head, having a nozzle row in which the plurality of nozzles are arranged, that ejects the liquid from the nozzles onto the printing medium; a second transport unit, disposed at a distance from the first transport unit downstream from the first transport unit, that further transports the printing medium transported by the first transport unit; and a control unit that causes the line head to execute a flushing operation for ejecting the liquid from the nozzles at a predetermined frequency, wherein when causing the line head to execute the flushing operation, the control unit provides a margin, where the liquid does not land, in a region corresponding to a predetermined distance from a leading end of the printing medium that is an end of the printing medium located toward the second transport unit.

Abstract: This invention enhances gloss uniformity of a formed image surface by selectively using colorless inks according to dot layouts of colored inks. A dot-layout unit sets colored dot layouts for respective colors of colored ink data. A colorless-dot-layout unit sets a colorless dot layout for one colorless ink with reference to a colorless dot layout table according to the colored ink data. An image is formed according to the colored and colorless dot layouts. In the colorless dot layout table, when a specular glossiness calculated according to the colored dot layouts is high, the colorless dot layout is set to superpose a colorless ink having a low refractive index on a colored ink having a high refractive index. Conversely, when the specular glossiness is low, the colorless dot layout is set to superpose a colorless ink having a high refractive index on a colored ink having a low refractive index.

Abstract: A defective recording element detecting apparatus includes: a read image data acquiring device which acquires read image data of a test pattern recorded on a recording medium by a recording head having recording elements; a reference area setting device which sets a reference area including a part of the test pattern on a read image representing image contents of the read image data; a comparison area setting device which sets a comparison area on the read image; a correlation operation device which performs a correlation operation between the comparison area and the reference area; a distortion correction value determining device which determines a distortion correction value, from a result of the correlation operation; an image distortion correcting device which corrects image distortion of the read image using the distortion correction value; and a defective recording element determining device which identifies a defective recording element according to the corrected read image.

Abstract: An ink jet printer for printing on a substrate comprising a first print head outputting ink and defining an ink meniscus; a platen operable to carry the substrate; a support structure; and a print head mechanism coupled to the support structure and carrying the first print head. The print head mechanism moves the first print head relative to the platen. A controller controls the print head mechanism such that at least one of a predetermined acceleration and predetermined deceleration of the print head mechanism is achieved such that the ink meniscus is operably maintained.

Abstract: A method of indirect printing has been developed to split printing of an imaging revolution on the image drum. A portion of the image is printed on the drum corresponding from an intermediate edge to a trailing edge of image data, and subsequently a remaining portion is printed corresponding from a leading edge to the intermediate edge of the image data. Splitting the image revolution enables the imaging to begin earlier in the drum revolution and decreases the total number of revolutions needed to complete a printed page, increasing printer throughput.

Abstract: A liquid discharge apparatus, comprising: a transportation unit that transports a medium; a head that includes a first nozzle array on which nozzles for discharging a first liquid are arrayed, and a second nozzle array on which nozzles for discharging a second liquid are arrayed; and a controller that controls the transportation unit and the head based on print data, wherein, in a case where the printing of the print data is designated to be performed without forming the printing dots of the first liquid on the medium, the controller causes the head to discharge the second liquid from the second nozzle array to form the printing dots of the second liquid on the medium, and causes the head to discharge the first liquid from the first nozzle array to form the flushing dots of the first liquid on the medium.

Abstract: A printing apparatus according to the present invention comprises a carriage configured to mount a printhead and reciprocate, a driving unit configured to move the carriage, the driving unit including a motor as a driving source, a measurement unit configured to measure a velocity fluctuation of the carriage, a correction unit configured to correct driving of the motor by correction data to reduce a velocity fluctuation of the carriage arising from cogging of the motor, and a setting unit configured to set a parameter which defines a periodic fluctuation manner of the correction data. The setting unit determines a current preferable value of the parameter based on the velocity fluctuation measured by the measurement unit for a current set value of the parameter, and sets a next set value of the parameter from the determined preferable value.

Abstract: When a paper jam is detected, in the case where the cause of the paper jam is a CR motor error in which the speed of the carriage is decreased by as much as a load when the paper jam occurs and becomes equal to or less than a set speed, when there is an instruction to continue printing, cleaning is performed on a printing head. In this case, it is determined whether the paper position is particularly in a one-side supporting range in which the paper is supported by only one pair of transporting roller pairs provided in each of an upstream side and a downstream side of a transporting direction of the paper with interposing of a moving path of the printing head. Then, it is preferable that cleaning be performed as long as the paper position is in the one-side supporting range.

Abstract: To ejecting a droplet from a reservoir, the reservoir holding a fluid is moved with respect to an acoustic ejector. As the reservoir and ejector move closer together, the acoustic ejector sends one or more interrogation pulses towards the reservoir. Based on the interrogation pulses, the system determines when the movement of the reservoir has placed a free surface of the fluid in a position where a droplet can be ejected.

Abstract: An ink composition has a viscosity of 25 mPa·s to 35 mPa·s at 20° C., wherein a, b, and c are 800 or more, 7.4 to 14, and 0.16 to 0.22, respectively, when a cylindrical portion is formed by expanding the ink composition so as to have a free surface parallel to the expanding direction of the ink composition, the rate of change in width of the cylindrical portion with time is measured in the expanding direction thereof, and the rate of change in width of the cylindrical portion with time is fit to a quadratic function given by the following equation: S=?at2?bt+c??(1) where S is the rate of change in width of the cylindrical portion and t is the time in seconds.

Abstract: An image recording apparatus, including: a first head for ejecting first liquid for recording; a second head for ejecting second liquid; and a controller. The controller selects, based on the image data, one of waveforms for ejecting the first liquid for each pixel and supplies, to the first-liquid ejection head, a drive signal based on the selected waveform. The controller selects, based on the image data, one of the of waveforms for ejecting the second liquid for each pixel and supplies, to the second-liquid ejection head, a drive signal based on the selected waveform. The controller determines whether recording of a test pattern using the second liquid is required, and when the recording of the test pattern using the second liquid is required, selects the waveform such that the first liquid is not ejected.

Abstract: According to an embodiments, a power supply device includes: a first voltage generator that operates to output a first voltage; a second voltage generator that operates to output a second voltage higher than the first voltage; a third voltage generator that, from the second voltage generated by the second voltage generator, operates to generate a third voltage equal to the first voltage and to output the third voltage therefrom; and a selector that operates to select as an output whichever has a higher voltage from the output of the first generator and the output of the second generator, wherein each of the output of the second voltage generator and the output selected by the selector are supplied to a load.

Abstract: A recording apparatus includes a recording head that ejects a liquid thereby performing recording on a recording medium, and a support member disposed so as to oppose the recording head. The support member includes a deposit recess located at a position corresponding to the respective end portion of the recording medium in the width direction intersecting with the transport direction, for receiving the liquid ejected to a region deviated from the recording medium in a marginless recording process, and a support region provided upstream of the deposit recess in the transport direction so as to support a back surface of the recording medium, and most upstream nozzles in the transport direction are not used in the marginless recording process.

Abstract: The invention improves uniform glossiness of a printed surface. Glossiness of each of inks installed in a printer is obtained. The inks are sorted in order of glossiness. The number of scans when forming an image by scanning each head is set for each of the inks sorted. Mask data for controlling the number of operations is created.

Abstract: A printer as an ink ejecting apparatus capable of ejecting sedimentation ink includes an LED as a first light emitting unit that emits light to a patch as a measurement target portion printed on a printing medium by the sedimentation ink, a light receiving sensor as a first light receiving unit that receives light transmitted from the LED and passing through the patch, and a control unit as a shielding degree determining unit that determines whether or not the patch has a predetermined shielding degree on the basis of a light reception signal output from the light receiving sensor.

Abstract: A detecting method for printing material boundary of a large UV inkjet printer includes steps of performing a full-field scanning process at a first scanning speed by a photosensitive element disposed on an inkjet module to cause a sensing device to produce induced voltage signals corresponding to different positions below sequentially in order to determine rough coordinate positions of two opposite sides of the printing material based on the changes of the induced voltage signals, and to define detailed scanning areas including the rough coordinate positions of the two opposite sides; and performing a detailed scanning process for the detailed scanning areas along an opposite direction at a second scanning speed slower than the first scanning speed by the photosensitive element in order to obtain boundary coordinate positions of the two opposite sides of the printing material based on the changes of the induced voltage signals.

Abstract: A method for controlling droplet ejection, wherein droplets ejected from an inkjet print head are to be received on a recording substrate and wherein the print head and the recording substrate are moveable relative to each other, includes determining a set of droplet ejection moments, the set of droplet ejection moments determining when a droplet may be ejected from the print head; moving the inkjet print head and the recording substrate relative to each other; predicting an actual relative position of the print head and the recording substrate at a droplet ejection moment; and determining whether or not a droplet is to be ejected at the droplet ejection moment depending on the predicted actual relative position and depending on the predetermined pattern. Thus, droplets may be ejected from the print head only at stable droplet ejection moments resulting in an increased stability of operation of the print head.

Abstract: A recording method using an inkjet recording apparatus 10 which performs recording on a travelling material to be recorded by a line head, including: a first step of setting resolutions to design regions of image data having a plurality of different design regions; a second step of setting a travelling speed of the material to be recorded so as to correspond to each of the resolutions; and a third step of setting acceleration/deceleration of the material to be recorded in order to connect different travelling speeds of the travelling speed, wherein the travelling speed of the material to be recorded is changed during continuous recording by the line head.

Abstract: To detect an edge part of a medium with accuracy although the medium includes a false detection element, more than one change point, which changes from a condition that an output of an optical sensor indicates existence of a print medium to a condition that the output indicates non-existence of the print medium, is detected while the optical sensor moved on the print medium along a main scanning direction. A right edge part candidate detection process and a left edge part candidate process are performed to detect at points immediately before output changes as the right and left edge part candidates of the medium when the output of the optical sensor continuously indicates a condition of non-existence of the medium while the optical sensor and the print medium are moved further along the main scanning direction for a predetermined distance from the detected change points.

Abstract: Uneven glossiness is effectively suppressed between areas where light inks are mainly used and areas where dark inks are mainly used. The gloss is raised in areas where dark cyan ink C is used. In other words, the application amount of second clear ink applied by after application printing is set to 32% at primary cyan (grid point 16) to equalize the gloss with areas where light cyan ink LC is used. Also, the application amount of first clear ink applied by common printing is set to 32% in a highlight portion (grid point 8) to equalize the gloss with the maximum gloss reached using dark cyan ink C. In so doing, it is possible to keep the gloss nearly constant over the entire range from white to cyan, or in other words, suppress uneven glossiness.

Abstract: A printing apparatus and temperature detecting method can accurately obtain temperature of a printing element substrate and output a high-quality image at high resolution and high speed. For this purpose, a first temperature sensor outputting signals through a first output line and a second temperature sensor outputting signals through a second output line that is longer than the first output line are provided on the printing element substrate. In addition, a switch between the case of using detected temperatures obtained from both of the first temperature sensor and the second temperature sensor to calculate the temperature of the printing element substrate, and the case of using only the detected temperature obtained from the first temperature sensor to calculate the temperature of a printing element substrate is made. On this basis, inaccurate temperature of a printing element substrate due to noise can be avoided.

Abstract: An image forming apparatus may include a pump mechanism for feeding ink to a recording head, a time counting unit capable of measuring a stop time determined by calculating a duration of time for which the ink was stopped from being fed to the recording head, an ink temperature detection unit, a first liquid feed control unit and a second liquid feed control unit. The first liquid feed control unit may instruct the pump mechanism to execute a preliminary purge when the measured stop time is not shorter than a first time. The second liquid feed control unit may instruct the pump mechanism to execute a main purge. And the second liquid feed control unit may set a flow rate in the main purge based on both the measured stop time and the detected ink temperature.

Abstract: In a method to execute a print interruption, a printing substrate is printed to with a printing unit with at least one print head. With aid of a sensor, print clock pulses are generated that are supplied to a print controller depending on a feed of the printing substrate. With triggering of the print interruption, a feed speed of the printing substrate is reduced from a print speed in the printing operation to a predetermined speed according to a deceleration ramp. After the print interruption the printing substrate is accelerated again to the print speed according to an acceleration ramp. Given occurrence of a print clock pulse during at least one of the ramps, the print controller sends at least one vibration pulse to the at least one print head so that at least one cycle of vibration oscillations is implemented at the print head. The at least one vibration pulse is generated if a time interval of the print clock pulses relative to one another reaches a predetermined value.

Abstract: In an embodiment, a method of compensating for capacitance change in a piezoelectric element of a fluid ejection device includes sensing a current driving a piezoelectric element, determining from the current that capacitance of the piezoelectric element has changed, and altering a rise time of the current driving the piezoelectric element to compensate for the changed capacitance.

Abstract: A method for calibrating a program that detects a condition of an inkjet nozzle includes receiving measurement information from a sensor positioned to detect a drive bubble in an ink chamber of an inkjet nozzle; and modifying a program that determines a condition of said inkjet nozzle.

Abstract: An inkjet printer forms ink images from image data including colors in a device independent color space. A color profile associated with the printer maps a plurality of colors in the device independent color space and to a plurality of ink colors formed from a plurality of inks in the printer. The plurality of ink colors only includes colors that are formed with an ink mass density that is below a predetermined threshold.

Abstract: Unevenness correcting information is generated based on property information indicating a recording property of each of a plurality of recording elements which are included in a recording head, the recording elements being subjected to output correction in a first output correction unit based on unevenness correcting information obtained after a flattening processing and output correction in a second output correction unit, and the unevenness correcting information close to an appropriate value with which an image in an appropriately-corrected state can be obtained can be generated.

Abstract: An image forming apparatus includes a shape information acquisition unit configured to acquire shape information indicating a shape of a three-dimensional object on which an image forming process is to be performed; a surface determination unit configured to determine a plurality of surfaces from which the three-dimensional object is constructed, based on the shape information; and an output image information generation unit configured to generate surface image information and join region image information. The surface image information is information on images to be formed on the respective surfaces. Each image is of a region obtained by cutting an end of the corresponding surface by a predetermined amount. The join region image information is information on an image to be formed on a join region between the adjacent surfaces.

Abstract: A control circuit for a drop-on-demand piezoelectric fluid-ejection mechanism includes a drive and sense circuit, and a switch. The drive and sense circuit has an input, a drive output, and a sense output. The drive output is to be coupled to the drop-on-demand piezoelectric fluid-ejection mechanism. The switch is to switch the input of the drive and sense circuit between a feed-forward driving mode of the drive and sense circuit and a feedback damping mode of the drive and sense circuit. In the feed-forward driving mode, the switch is to couple the input to a drive waveform to cause the fluid-ejection mechanism to eject a drop of fluid. In the feedback damping mode, the switch is to couple the input to the sense output to dampen the fluid-ejection mechanism after the fluid-ejection mechanism has ejected the drop of fluid.

Abstract: Printing methods are provided. In one method, printing an inkjet image using a liquid hydrophilic inkjet ink onto a surface of a semi-absorbent recording medium generating a toner image having toner particles arranged conforming to the inkjet image and transferring the toner image onto the recording medium where an unabsorbed volume of the inkjet ink is present on the recording medium. The toner particles manage unabsorbed volumes of the inkjet ink to protect the recording medium from image artifacts that can be created by an unabsorbed volume of the inkjet ink on the surface without a liquid management toner image.

Abstract: A liquid ejection apparatus includes a liquid ejection head including a plurality of ejection opening groups each constituted by two or more ejection openings and each forming one pixel by at least two liquid droplets ejected from the two or more ejection openings; a plurality of individual channels respectively connecting the plurality of ejection opening groups to a plurality of pressure chambers; a nozzle plate through which a plurality of nozzle holes extend; and an energy-applying portion applying energy to liquid in the plurality of pressure chambers, and a controller controlling the energy-applying portion. The controller controls the energy-applying portion in such a manner as to meet the following inequations: 0.85Ta?T?0.9Ta or 1.2Ta?T in a case of p/D?1.2, and 0.85Ta?T in a case of p/D>1.2.

Abstract: An image forming apparatus includes: a dot image forming unit executes one of: (i) a default mode of forming a dot image of an entire rectangle by placing an internal dot group corresponding to a fill of an inside a rectangle and a contour dot group corresponding to a contour of the rectangle based on a first dot placement rule and a second dot placement rule, respectively; or (ii) a change mode of forming the dot image of the rectangle by unifying dot placement rules into either of the two dot placement rules and placing the internal dot group and the contour dot group; and an image formation control unit causes, in the change mode, the dot image forming unit to unify the dot placement rules into either of the two dot placement rules and to place the internal dot group and the contour dot group.

Abstract: A method for aligning multi-channel digital image data for a digital printer having an array of printheads for each of a plurality of channels is described. A test pattern including test pattern indicia printed using individual printheads is scanned and analyzed to detect locations of the printed test pattern indicia. For each array position, one of the printheads is designated to be a reference printhead, and one or more of the other printheads are designated to be non-reference printheads. Spatial adjustment parameters are determined for each of the non-reference printheads responsive to the detected test pattern indicia locations. Digital image data to be printed with the non-reference printheads is modified in accordance with the determined spatial adjustment parameters.

Abstract: Methods for operating a printing system are provided. In one method, an inkjet image is printed on a receiver using a hydrophilic ink and an image of the receiver is captured after predetermined period of absorption. Local areas of the image of the inkjet print that have reached a threshold level of non-uniform distortion and where additional ink remains for absorption are identified. A distortion estimate is determined for distortion of the receiver at a time when a second image will be printed on the receiver based upon information from the identified areas. A second print image is printed based on the distortion estimate; and, the second image is printed.

Abstract: A liquid ejecting apparatus includes a head having a first ejecting unit including a first liquid ejecting nozzle, a first pressure chamber communicating with the nozzle, and a first drive element, and a second ejecting unit including a second liquid ejecting nozzle, a second pressure chamber communicating with the nozzle, and a second drive element. The first nozzle ejects liquid by applying a drive signal to the first drive element, and the second nozzle ejects liquid by applying the drive signal to the second drive element. The first nozzle state is determined using a first detection signal obtained by applying a first drive signal to the first drive element and a second drive signal to the second drive element, and a second detection signal obtained by applying the first drive signal to the first drive element and a third drive signal to the second drive element.

Abstract: A liquid ejection apparatus includes a liquid ejection head including a plurality of ejection opening groups each constituted by two or more ejection openings and each forming one pixel by at least two liquid droplets ejected from the two or more ejection openings of a corresponding one of the plurality of ejection opening groups; a plurality of individual channels respectively connecting the plurality of ejection opening groups to a plurality of pressure chambers; and an energy-applying portion applying energy to liquid in the plurality of pressure chambers, and a controller controlling the energy-applying portion. The controller controls the energy-applying portion to form one pixel by using at least a first drive signal whose ejection period is a first ejection period and a second drive signal whose ejection period is a second ejection period different from the first ejection period.

Abstract: Displacement information indicating a displacement amount of landing position in a main scanning direction of ink droplets discharged respectively from the nozzle of the head module of the same array of the line head of each color is acquired for each head module of the same array (steps S5, S7). Based on the displacement information and concentration information for each array, a color degree of an image when the discharge amount of ink droplets discharged from a nozzle of a head module of each color is not adjusted is specified for each head module of each array (step S9). A correction voltage value of a drive signal for the discharge of the nozzle of the head module of each color, which is suitable to return the specified color degree to “0”, is calculated (step S11) and each corresponding nozzle is driven by the drive signal of the correction voltage value.

Abstract: A liquid ejection apparatus comprises a plurality of piezoelectric element units, which can be driven to eject liquid by changing a drive voltage, and a control device. The control device may calculate an accumulated time for each of the piezoelectric element units. The accumulated times may be a time that a respective piezoelectric element unit is in a driven state. The control device may also identify a first piezoelectric element unit having a maximum accumulated time and a second piezoelectric element unit having a minimum accumulated time from among the piezoelectric element units. The control device may reduce the drive voltage applied to one or more of the piezoelectric element units that are not in the driven state to a lower voltage, when the control device determines that the difference between the maximum accumulated time and the minimum accumulated time is less than a predetermined time.

Abstract: Image processing of printed patterns of arrays of dots generated by an array of inkjet heads uses a vision system, including an HD color camera that can be a fixed focus or include autofocus and zoom capabilities. Pattern recognition techniques are used to analyze as many patterns as necessary to perform multiple alignment functions, such as dot size, shape, and integrity; unidirectional, bidirectional, and step alignments; physical position and straightness of jet packs; flatness of platen or media belt; mapping imperfections in rods and rails of guiding systems; and checking jet alignments from a reference jet to all other jet packs. From such image analysis, correction values are generated that are used to effect manual or automatic adjustment of the inkjet heads physical position, voltage, temperature, and firing pulse timing and/or duration; and to position the printed dots fired from the nozzles in the inkjet heads in the appropriate position.