Abstract: An ink jet recording head and an ink jet recording apparatus which can be manufactured at low cost and with a continuous length by using nonlinear elements having MIM-type electrical characteristics to drive heat generating members having a bubble jet recording system so as to prevent the nonlinear elements from being destroyed by a heat generation of the nonlinear elements.

Abstract: A boundary nozzle which is contained in a block that has not been driven and is situated at the boundary with a driving block that is driven prior to the block containing the boundary nozzle contains a second stopper which has a length in a liquid flow direction longer than that of a first stopper contained in a driving nozzle in the driving block that is driven prior. A near-boundary nozzle adjacent to the boundary nozzle has a third stopper which has a length in a liquid flow direction longer than that of the first stopper but shorter than the second stopper. Thus, recording irregularities owing to meniscus regression are suppressed.

Abstract: A printhead mainly includes at least two ink supply holes on a single semiconductor substrate, a first signal processing circuit laid out at at least one corner of the semiconductor substrate to arbitrarily select a heater for heating the ink, and a second signal processing circuit, other than the first signal processing circuit for arbitrarily selecting a heater, that realizes a function without dividing an arrangement. The lengths of signal lines are minimized to realize a printhead free from any malfunction.

Abstract: To provide an ink jet recording apparatus wherein distorting the waveform of a drive signal can be prevented, a recording head also containing a drive signal generating circuit can be tested, and the detrimental effect when such a configuration is adopted can be avoided. In the ink jet recording apparatus, a heat radiation member 200 is placed in a recording head 100 and an IC 300 is mounted on a vertical plate section 210 of the heat radiation member 200. The IC 300 is provided with not only a head drive circuit, but also a current amplification circuit of a drive signal generating circuit for generating a drive signal to drive a pressure generating element 17. The recording head 10 is attached to a carriage in a state in which the vertical plate section 210 of the heat radiation member 200 is brought into contact with the carriage with heat radiation fins.

Abstract: A printhead mainly includes at least two ink supply holes on a single semiconductor substrate, a first signal processing circuit laid out at at least one corner of the semiconductor substrate to arbitrarily select a heater for heating the ink, and a second signal processing circuit, other than the first signal processing circuit for arbitrarily selecting a heater, that realizes a function without dividing an arrangement. The lengths of signal lines are minimized to realize a printhead free from any malfunction.

Abstract: An ink jet recording apparatus, in which thermal energy is applied to ink in accordance with a driving signal applied to a heater to produce a bubble, by which ink is ejected onto a recording material, includes a driver for applying a plurality of driving signals to the heater for one ejection of one ink droplet. The driving signals comprise a first driving signal not ejecting the ink and a second driving signal for ejecting the ink, the second driving signal being applied after a rest period after the first driving signal. The apparatus further includes a controller for changing an amount of ink ejected by changing a length of the rest period and changing the first driving signal. The controller effects its changing operation in a first changing region in which the rest period is changed without changing the first driving signal and in a second changing region in which a length of the first drive signal is changed.

Abstract: In an ink-jet apparatus employing an ink-jet head having a plurality of heaters corresponding to one ink ejection opening, appropriate preliminary ejection is performed per each ejection amount mode set by a heater to be used among a plurality of heaters. Depending upon a set printing mode, printing is performed in one of large, medium and small ejection amount modes. For example, after printing is performed for a predetermined amount by the small ejection amount mode, preliminary ejection during printing is performed in the medium ejection amount mode, which is greater in ejection amount than the small ejection amount mode. By this, the interval between preliminary ejections during printing can be set to be longer to prevent lowering of throughput due to the preliminary ejection operations.

Abstract: In a thermal ink jet print head, individually-controlled heating elements are separated into groups of heating elements. Redundant control lines for the separate groups of heating elements increase the print head's reliability by reducing the likelihood that a print head will be completely disabled by an electrical fault on the control lines that in prior art devices extended to all of the heating elements.

Abstract: The present invention is a printing system and method having a printhead assembly that controls firing operations of an inkjet printhead. In particular, the system and method control the firing and timing decisions pertaining to ink drop ejection through the use of various types of delays. The printing system includes a controller, a power supply and a printhead assembly. The printhead assembly includes a memory device and distributive processor integrated with an ink driver head.

Abstract: Energy applied to a heater for ejecting an ink is set to more than bubble generation threshold energy Eth and less than predetermined energy Eo, or to more than the predetermined energy Eo. Thereby, when an image to be printed is one of low ejection duty, an ejection where a bubble communicates with the atmosphere before the ink droplet separates from an ejection port (BTHJ ejection) is performed. On the other hand, when the image is one of high ejection duty, an ejection not communicating with the atmosphere as above (BUBBLE-JET ejection) is performed. As a result, an increase of ink mist due to satellites can be suppressed as a whole even if satellites are increased because of BTHJ ejection. When the ejection duty is high, generation of satellites themselves is reduced, thereby suppressing increase of ink mist.

Abstract: The present invention provides an ink jet recording head in which the degree of freedom in the design of the arranged position of an electric signal input-output terminal is enhanced, its manufacturing method and an ink jet recording device, the invention is characterized as follows. The ink jet recording head is formed by laminating a heater element substrate in which a heater element and others are arranged and a passage substrate in which nozzles and others are formed. When the nozzles and others are formed by etching in the passage substrate, a cut-out portion for exposing an electric signal input-output terminal of the heater element substrate is also formed. Therefore, the degree of freedom in the design of the shape and the position of the cut-out portion in the head chip is enhanced.

Abstract: This present invention is embodied in a low-cost printing system including a printhead and an ink composition that provides photographic-quality resolution. The printhead of the present invention includes a high-density array of drop generators that eject ink drops having a low drop weight and that operate at a high frequency. Further, high-resistance firing resistors are used to provide minimum energy dissipation and the firing resistors are preferably thin-film resistors to ensure that a minimal amount of energy is needed to eject ink drops. The stability of the ink drop volume is maintained by including an overdamped structure within the ink drop generators that allow the ink chambers to fill up with ink slowly. The ink composition of the present invention includes an ink additive that prevents decel from occurring during sustained high-frequency printing bursts.

Abstract: In an ink-jet apparatus employing an ink-jet head having a plurality of heaters corresponding to one ink ejection opening, appropriate preliminary ejection is performed per each ejection amount mode set by a heater to be used among a plurality of heaters. Depending upon a set printing mode, printing is performed in one of large, medium and small ejection amount modes. For example, after printing is performed for a predetermined amount by the small ejection amount mode, preliminary ejection during printing is performed in the medium ejection amount mode which is greater in ejection amount than the small ejection amount mode. By this, the interval between preliminary ejections during printing can be set to be longer to prevent lowering of throughput due to the preliminary ejection operations.

Abstract: A driver circuit for an matrix type inkjet printhead having a plurality of first heater resistors arranged in a matrix comprising a plurality of groups of heater resistors. The driver circuit comprises a plurality of first switches and a plurality of second switches. Each of the plurality of first switches is coupled to a heater resistor in each of the plurality of groups and is responsive to one of a plurality of first control signals to supply a current to the associated heater resistor. Each of the plurality of second switches is associated with one of the plurality of first switches, and comprises an input, an output and a gate. The input of each of the plurality of second switches is coupled to one of the plurality of first control signals, and the output of each of the plurality of second switches is coupled to the plurality of first switches for one of the plurality of groups of heater resistors.

Abstract: An inkjet head is provided with a flexible printed circuit cable where a head body for ejecting ink and a connector are mounted at places different from each other, and the flexible printed circuit cable is bent between the head body and the connector so as to absorb tensile and pushing forces applied to the connector. The inkjet head is also provided with an ink ejecting portion for ejecting ink, a head-side connector and a supporting body or a cover for supporting or storing an electric connection portion or a flexible printed circuit cable interposed between the ink ejecting portion and the connector, and the head-side connector is supported by the supporting body or the cover so that the connector is movable in the three-dimensional directions.

Abstract: A substrate having plural recording elements and electrical leads for supplying electric signals to the recording elements includes electrical contacts for external electrical connection for reception of image signals used for driving the recording elements; and a processing circuit for converting signals which are serially supplied to the connecting contact to parallel signals to be applied to the recording elements.

Abstract: The present invention is directed to resolve the noise problem with the ink in an ink jet head without changing the substrate manufacturing process for the ink jet head, that is, increasing the cost on the manufacture, and without needs of disposing a noise countermeasure component on the side of the printer main device, or making the design change for the countermeasure. The present invention is characterized in that to prevent malfunction from arising by the noise, a hysteresis circuit to provide different input data threshold values upon rising and falling is provided on an input portion of the signal for a drive control logic system such as a drive input signal for a shift register and a latch circuit on the same substrate as that of the heating elements, the driver and the drive control logic circuit, utilizing a diffusion layer constituting a driver.

Abstract: For an inkjet printing apparatus having a large number of ink ejectors, it is desirable to have as few as possible interconnections to the ink ejectors. Sharing electrical ground returns between related ink ejector primitive groups with spaced apart terminals provides a reduction in interconnections while offering redundancy in the interconnection.

Abstract: A liquid jet recording apparatus for jetting ink droplets to a recording medium in accordance with image data on demand so that an image having pixels corresponding to the image data is formed on the recording medium. The liquid jet recording apparatus includes ink jetting orifices from which ink droplets are jetted. An area of each of ink jetting orifices is equal to or less than 500 &mgr;m2. Control means controls a frequency with which the ink droplets are jetted to fall within a range from 8 KHz to 40 KHz and a number of ink droplets for each pixel of the image formed on the recording medium based on the image data under a condition in which the number of ink droplets is equal to or less than twenty.

Abstract: A method of operating a thermal ink jet printer with a removable print head having a plurality of ink firing resistors, the operation including calibrating the printer by determining a nominal input voltage above a threshold necessary for simultaneous operation of a plurality of the resistors. Then, during printing, detecting the input voltage on the print head at an input node connected to the resistors and generating a firing pulse having a duration based on the detected input voltage at the node. Thus, a detected input voltage higher than the nominal voltage is compensated for by a shortened firing pulse. The method may be achieved in a removable ink jet print head having a connector with many electrical inputs connectable to a printer, and a voltage input node connected to the connector. The print head has numerous firing resistors connected to the input node.

Abstract: An ink jet recording apparatus includes an ink jet recording head as an essential component, and the ink jet recording head has a wiring structure which assures that a quantity of electricity loss induced by wiring resistance can be reduced. A plurality of substantially rectangular heaters 2 are formed at the positions in the vicinity of one end edge 1a of a device substrate 1 while they are arranged in an array in parallel with the one end edge 1a of the device substrate 1 with a predetermined distance held between adjacent heaters 2. Each heater 2 is composed of heaters 2a and 2b in the form of a pair. A common wiring portion 3 made of a metallic material such as aluminum or the like is formed between a pair of heaters 2, and it is electrically connected to electrodes of the heaters 2 on one side of the latter on the common basis.

Abstract: An apparatus addresses ink jet heating elements based on image data to cause ejection of ink droplets toward a print medium. The apparatus includes a controller for generating address signals, power signals, and first and second bank signals. The first and second bank signals, which are carried on first and second bank lines, alternate between on and off states. The first bank signal is off when the second bank signal is on, and the second bank signal is off when the first bank signal is on. The apparatus has m address lines and n power lines connected to the controller for carrying the address signals and the power signals. A print head has m×n number of first driver circuits, each of which is connected to the first bank line and to a corresponding one of the m address lines. The first driver circuits enable flow of a first driving current when the first bank signal and the address signal are simultaneously on on the first bank line and the corresponding address line.

Abstract: A printer control apparatus includes a rotary encoder for detecting the rotational position of a rotary drum around which printing paper is wound and outputting a timing pulse, a reference point pulse creating circuit for outputting a reference point pulse based on the timing pulse, an up-counter for measuring the passage time of the reference point interval based on the reference point pulse, a plurality of comparators for generating a train of print timing pulses in a time interval corresponding to and shorter than the passage time of the reference point interval measured, a multiplier circuit having a different up-counter for determining the total required time of the train of print timing pulses, a print timing correction circuit for correcting the print timing pulse train based on the driving frequency of the ink-jet print head, and a head drive circuit for driving the head according to the print timing pulse train from the correction circuit.

Abstract: An inkjet printhead having a plurality of ink discharge nozzles that are served by respective ink supply conduits formed within a composite substrate includes ink discharge heaters respective to each of the nozzles, one or more substrate heaters for preheating an ink flow within the supply conduits and a plurality of resistors for monitoring the printhead quality during manufacture. The ink discharge heaters are in circuit with a first energy source connection and a common ground connection. The quality monitoring resistors are in series circuit with a second energy source connection and the common ground connection respective to the ink discharge heaters. At least one substrate heater is in circuit with a third energy source connection and the second energy source connection which, when the printhead is operatively connected for printing, is connected to ground.

Abstract: In an ink droplet ejection drive method and apparatus, after plural ink emission pulses are generated for each one-dot print instruction or after plural ink emission pulses for plural one-dot print instructions, an ink nonemission pulse is generated to reduce residual pressure wave oscillation in an ink channel. The emission pulses and the nonemission pulse have the same voltage polarity and amplitude. The emission pulse has a time width corresponding to a one-way propagation time T of pressure wave in the ink channel, i.e., 8 .mu.sec., while the nonemission pulse has a time width in a range of 0.3 T to 0.7 T or 1.3 T to 1.8 T. A period between the end time of the last emission pulse and the intermediate time corresponding to the midpoint between the start time and the end time of the nonemission pulse is determined to be in a range of 2.35 T to 2.65 T.

Abstract: An information recording apparatus has a large plurality of heat energy generating elements corresponding to a like plurality of ejection ports for ejecting ink. The heat energy generating elements cause a change in the state of the ink by heating the ink in response to a drive signal, thereby ejecting ink droplets from corresponding ejection ports. A selection signal sequentially selects from among plural groups of plural heat energy generating element and an information storing device stores recording information, portions of which correspond respectively to selected groups of the heat energy generating elements. A drive circuit supplies drive signals to the selected groups of heat energy generating elements, the drive signals for each group being supplied in accordance with the corresponding stored portion of the recording information.

Abstract: An ink jet print head has first nozzles of a first diameter for ejecting droplets of ink having a first mass, and second nozzles of a second diameter for ejecting droplets of ink having a second mass. The first diameter is larger than the second diameter, and the first mass is larger than the second mass. First and second heater-switch pairs are connected in parallel on a substrate of the print head. The first heater-switch pairs include first heaters adjacent corresponding first nozzles, and the second heater-switch pairs include second heaters adjacent corresponding second nozzles. The first and second heaters are composed of electrically resistive material occupying first and second heater areas on the substrate. The first heater-switch pairs also include first switching devices connected in series with the first heaters, with each first switching device developing a first switching device voltage drop as a first electrical current flows through.

Abstract: The invention described herein relates to a method for printing with a thermal ink jet printer. A thermal ink jet print head containing a plurality of resistance heaters is provided. To each resistance heater there is an electrical current path, and each resistance heater also has a surface for heating the ink adjacent the surface. By providing an electrical current to the heaters to heat the ink such that a heater power density of at least about two gigawatts per square meter is obtained, print quality may be dramatically improved.

Abstract: A printhead, constructed with a plurality of common-type element substrates which sandwich a connecting board, which performs printing by utilizing a common-type control signal. The element substrate integrates: a plurality of heaters 101 which are arrayed in one line, power transistors 102, a shift register 104, a latch circuit 117, an AND circuit 119, terminals 114 to 116 for inputting block-selection signals, a terminal 120 for inputting an inverse instruction signal which instructs to invert the block selection signal, a block inverter 121 for inverting the block-selection signal in accordance with the inverse instruction signal, and a 3 to 8 decoder 118 for selecting one of a plurality of blocks. By utilizing a printhead where at least two of the element substrate are arranged opposite to each other, and where plural arrays of printing elements are formed, printing is performed by dividing a plurality of printing elements into a plurality of blocks and time-divisionally driving each block.

Abstract: Imaging apparatus and method adapted to control ink droplet volume and void formation. The apparatus includes an ink jet print head having a nozzle for ejecting an ink droplet therefrom. A heater element is in heat transfer communication with the ink droplet for variably supplying heat energy to the ink droplet, so that the volume of the ink droplet is controlled as the heat energy is variably supplied to the ink droplet. A controller is connected to the heater element for variably controlling the heat energy supplied to the ink droplet. The controller variably controls the heat energy by variably controlling a plurality of voltage pulses sequentially supplied to the heater element. Moreover, in order to reduce the potential for void formation in the ink droplet, the pulses are spaced-apart by a predetermined delay interval.

Abstract: A recording head system for an ink jet recording apparatus having a full-line recording head. The recording head is divided into a variable number of blocks. The recording ratio of each block (that is, the ratio of the number of ink ejecting elements to be driven in a block in accordance with recording data to the total number of the ink ejecting elements in the block) is compared with a reference recording ratio. When the recording ratio is greater than the reference recording ratio, the interval between the drive timing of a block and that of the next block is lengthened, or vise versa. This is performed by controlling the enable timing of each block by D-flip-flops, AND gates and delay circuits. Unevenness of recorded images resulting from the fluctuation in periodic ink pressure can be ameliorated.

Abstract: The invention is directed to an ink jet printer including a printhead and a printhead driver. The printhead includes a substrate, a nozzle plate having a plurality of ink emitting orifices, a plurality of jetting heaters on the substrate and respectively associated with the plurality of ink emitting orifices, and at least one substrate heater associated with the substrate. Each of the jetting heaters and the substrate heaters include first and second terminals. The printhead driver has a plurality of energizable outputs including at least one power line output and at least two enable line outputs. One power line output is electrically connected to a first terminal of each of a jetting heater and a substrate heater. Two of the enable line outputs are coupled to a second terminal of the jetting heater and a second terminal of the substrate heater.

Abstract: A data control apparatus is structured to execute complementary recording on one pixel array by dividing the scans of a recording head into four. In a nozzle context memory, the nozzle context data, which can be updated, are stored as control data to determine discharge or non-discharge of ink from discharge ports. In an operational circuit, the nozzle context data and image data are processed operationally, thus outputting drive data for the recording head. The data that indicates ink discharge in one pixel array are sequentially assigned to recording data per scan appropriately by use of the nozzle context data and the operational circuit. With the structure thus arranged, it is possible to implement making the capacity of memory smaller for use of data to control recording or non-recording, and also, to execute an intermittent recording by controlling recording or non-recording as required.

Abstract: An ink jet recording head has an energy generating device line constituted by electrically connecting N (N>1) energy generating devices in series. The energy generating devices are disposed to correspond to a plurality of discharge ports for discharging ink and generate discharging energy. The energy generating device line is operated by using substantially N+1 electrodes. The method of operating an ink-jet recording head comprises the steps of: successively selecting the energy generating devices of the energy generating device line; applying voltages of different levels to the two terminals of the selected energy generating device having received an image signal instructing the selected energy generating device to discharge the ink; and applying voltages of the same level to the two ends of the energy generating device which corresponds to the discharge ports which are not to discharge the ink.

Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.

Abstract: A printing head for an inkjet printer having two head sections, each featuring discharge nozzles, the two head sections being capable of discharging variable size ink drops to form varying printed dot diameters. One of the head sections has a first dot diameter range, and other head section has a second dot diameter range. A portion of the second dot diameter range overlaps the first dot diameter range. For gradation printing, the head sections of the printing head can be controlled to print an image utilizing the respective dot diameter ranges for each head section; however, for text printing, the head sections of the printing head are controlled to print an image utilizing the overlapping portion of the two dot diameter ranges. The printing head is capable of both high-quality, high-definition gradation printing as well as high-speed text printing.

Abstract: A recording head has a plurality of recording elements which are divided into a plurality of blocks and each block is driven in a time division fashion. The recording head has a signal generation circuit for generating an output signal for selecting a drive block in response to an input signal for designating the drive block from a main body of a recording apparatus. The number of signal lines of the input signal is smaller than the number of signal lines of an output signal. One such recording head is provided for each of a plurality of colors to record a color image. Signal lines of an input signal are common to the respective recording heads. Thus, the number of signal lines between the recording heads and the main body of the recording apparatus is reduced and cost reduction and space saving are attained.

Abstract: An ink jet recording apparatus includes an ink jet recording head which has an ink ejection outlet, an ink passage, a heater for heating ink to form a bubble in the ink so as to allow a part of the ink to be ejected from the ink ejection outlet in the form of an ink droplet, and a driving circuit for applying a driving signal group to the heater. The driving signal circuit serves to apply a driving signal group including one or more pulses per a single pixel to the heater corresponding to the value representing an input image signal. In response to this input image signal, an ink droplet group having independent ink droplets is ejected from the ejection outlet toward a recording sheet. Since a quantity of ink ejected per a single pixel is variably controlled by changing the number of ink droplet ejection, each recording operation can be achieved while maintaining excellent gray scale properties.

Abstract: A liquid ink, drop on demand page-width print-head comprises a semiconductor substrate, a plurality of drop-emitter nozzles fabricated on the substrate; an ink supply manifold coupled to the nozzles; pressure means for subjecting ink in the manifold to a pressure above ambient pressure causing a meniscus to form in each nozzle; a means for applying heat to the perimeter of the meniscus in predetermined selectively addressed nozzles; and a means for combined selection and ejection of drops from the selectively addressed nozzles.

Abstract: An ink jet recording apparatus for recording onto a recording medium by using a recording head for discharging the ink, comprising a heater provided in the recording head and a resistor provided externally of the recording head to determine the resistance of the heater provided in the recording head, thereby selecting the drive conditions of the recording head.

Abstract: To remove deposit on a protective film 6 of heating resistors 3, main pulse P3r of multi-pulse drive is set to the width narrower than main pulse width P3s at the normal recording time and wider than the main pulse width starting film boiling in a region on the protective film including heating regions of the heating resistors, and the heating resistors 3 are driven, whereby the deposit is peeled in a wide area including the heating region. After bubbles grow in an ink chamber 9, they shrink and disappear as the heating resistors 3 terminate heating. Liquid rapidly flows into the ink chamber 9 accordingly, and the deposit on the protective film can be removed by cavitation at the time.

Abstract: An ink jet head includes ink ejection outlet for ejecting ink, a plurality of heat generating resistors for generating thermal energy contributable to ejecting the ink, and ink flow path comprising the plurality of the heat generating resistors and being in fluid communication with the ejection outlet, the heat generating resistors generating the thermal energy upon receiving a driving signal, so that a bubble is generated in the ink within the ink flow path to eject the ink through the ink ejection outlet; wherein the plurality of the heat generating resistors are arranged in parallel, relative to the ink ejecting direction, in the ink flow path, and the distances from the heat generating centers of the heat generating resistors to the ejection outlet are different.

Abstract: In an ink ejection type recording device in which expansion of bubble ejects an ink droplet from a nozzle toward a recording medium, a heater formed in an ink channel is applied with a pulse of voltage by a driver circuit. The pulse of voltage is determined so that the surface of the heater in direct contact with the water-based ink is rapidly heated to a temperature causing to invoke caviar-wise nucleation of the ink that is in direct contact with the surface of the heater. Expanding bubbles resulting from the caviar-wise nucleation ejects an ink droplet from the nozzle, wherein the heater is heated at a heating speed in a range from 1.times.10.sup.8 .degree. C./sec to 5.times.10.sup.8 .degree.C./sec, and the surface of the heater is heated up from a room temperature to a temperature substantially equal to 320 C within a period of time ranging from 0.6 to 3 .mu.sec.

Abstract: A technique for resetting the time for driving a print head of an ink-jet printer, based on different absorptivities of papers to be printed by the ink-jet printer, optimizes the amount of ink emerging from nozzles of the head resulting in a high print resolution. The technique includes: displaying different paper types on a display; selecting one type of paper out of the displayed paper types; obtaining a head driving time corresponding to the selected paper type from a look-up table prestored in a memory device and changing the predesignated head driving time to the obtained head driving time; and printing data with the changed head driving time.

Abstract: An ink jet recording apparatus comprises an ejection orifice for ejecting an ink, a supply portion, communicating with the ejection orifice, for supplying an ink stored therein to the ejection orifice, an ejection energy producer, arranged in the supply portion, for applying energy for ink ejection to the ink, a pressure producer, arranged in the supply portion at a position different from the ejection energy producer, for producing a pressure wave in the supply portion, and a controller for controlling the pressure producer to produce a pressure wave different from a pressure wave produced in the supply portion by the ejection energy producer.

Abstract: A method and apparatus for producing a thermal pulse for a drop on demand printer actuator. A varying voltage pulse is applied to a resistance heater forming part of the actuator, which generates time varying power in the resistance heater. The power varies with respect to time in a manner comprising:1) a pre-heating stage, which raises the temperature of the actuator, but is of insufficient total energy to actuate the printing actuator;2) a stage of increased power which rapidly raises the temperature of the actuator to the required temperature for operation;3) a stage of decreased power, which is less than the power in stage (b) but is sufficient to maintain the temperature of the temperature at the required temperature for operation;4) a stage of low or zero power, during which the temperature of the temperature rapidly falls below the required temperature for operation.

Abstract: A recording apparatus records an image by driving plural recording elements in blocks, into which the plural recording elements are divided. The plural blocks are divided into plural groups, each group having more than one block. A driving circuit drives each of the blocks independently. The driving circuit effects recording with high resolution or low resolution by respectively driving plural groups at a different timing in a first mode and driving the plural groups at a same timing in a second mode.

Abstract: An ink jet recording apparatus comprises a driving circuit for sequentially supplying drive signals according to recording information and an ink jet recording head that deposits ink onto a recording medium in response to the drive signals. The apparatus determines if the supply of drive signals has been interrupted for a predetermined time period. If so, when the supply of drive signals resumes, a recording control circuit increases the energy of a predetermined number of drive signals. With this arrangement, the recording density can be maintained uniform, even if there are gaps in the recording information.

Abstract: Variation of ink droplet velocity and droplet mass in thermal ink-jet print heads having at least one primary heater element is achieved by means of a circuit for generating time-shifted heating pulses. The heater element structure is such that there is at least one secondary heater element in addition to and physically separated from each primary heater element. The circuit for generating time-shifted heating pulses for the primary and secondary heater elements applies those pulses in such a way that a vapor bubble has already formed in the printing fluid on the secondary heater element at the point at which a vapor bubble starts to form in the printing fluid on the primary heater element.

Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.