Abstract: The disclosure relates to a method for correcting image data acquired by a magnetic resonance device, a magnetic resonance device, and a computer program product. According to the method, first navigator data, image data, and second navigator data are acquired. Moreover, temperature values of the magnetic resonance device are determined. The image data is corrected based on the first navigator data, the second navigator data, and the temperature values.

Abstract: A fluid ejection device including a plurality of primitives each having a same set of addresses and including a plurality of fluid chambers, each fluid chamber corresponding to a different address of the set of addresses and including a firing mechanism. Input logic receives a series of fire pulse groups, each fire pulse group corresponding to an address of the set of addresses and including warming data having an enable value or a disable value and a series of firing bits, each firing bit corresponding to a different primitive and having a firing value or a non-firing value. For each firing bit of each fire pulse group, when the warming data has the enable value, activation logic provides a warming pulse to the firing mechanism of the fluid chamber corresponding to the firing bit when the firing bit has the non-firing value.

Abstract: A printer according to an embodiment includes a communication interface that receives print data from an external device. A print head prints on a sheet, line by line according to the received print data. A motor drives a roller to transport the sheet, line by line according to the received print data. A processor configured determines, for a current print line, a target transport speed for transporting the sheet, and determines one or more intermediate speeds defined in advance and between a current transport speed of transporting the sheet and the target transport speed. The processor controls the motor to transport the sheet at each determined intermediate speed and the target transport speed, sequentially.

Abstract: A thermal printer according to an embodiment includes a communication interface that receives print data from an external device. A thermal print head thermally prints on a sheet, line by line according to the received print data. A motor drives a roller to transport the sheet, line by line according to the received print data. A processor determines, for a current print line, a target transport speed for transporting the sheet, and retrieves one or more intermediate speeds that are defined in advance and are between a current transport speed of transporting the sheet and the target transport speed. The processor controls the motor to transport the sheet at each determined intermediate speed and the target transport speed, sequentially. The thermal print head is heated in accordance with predetermined heating control information corresponding to the determined intermediate speed closest to the current speed.

Abstract: First and second sensors attached to a living body are connected to first and second input connectors respectively. An analog-to-digital converter converts a first analog voltage signal input from the first sensor through the first input connector into a first digital voltage signal. A first voltage-to-current converter converts the first digital voltage signal into a first analog current signal. A first interface connector outputs a second analog voltage signal and the first analog current signal, the second analog voltage signal being input from the second sensor through the second input connector. A physiological information processing apparatus has a second interface connector through which the first analog current signal and the second analog voltage signal are input to the physiological information processing apparatus.

Abstract: A base material processing apparatus detects the amount of widthwise misregistration of a base material in each detection position (Po, and Pa to Pd) lying on a transport path, and then calculates a difference between a detection value in the reference position (Po) and a detection value in each of the remaining detection positions (Pa to Pd) as a meandering amount. Subsequently, the base material processing apparatus determines coefficients obtained when a variation with time in each meandering amount is applied to a predetermined model function, and thereafter calculates coefficients of the model function predicted as the meandering of the base material in each processing position (P1 to P4), based on the determined coefficients and a positional relationship between the reference position (Po), the remaining detection positions (Pa to Pd) and the processing positions (P1 to P4).

Abstract: A method for controlling a thermal printhead of a printer. The printhead comprises an array of printing elements. The method may comprise performing a plurality of printing operations, each printing operation comprising energization of one or more printing elements. A respective energization value is determined for each printing element based upon energizations of that printing element during said printing operations. A printhead control signal is generated for the printhead for a subsequent printing operation based upon the energization values of a predetermined subset of the printing elements.

Abstract: An image forming system includes a plurality of image forming apparatuses, a determining unit, and a control unit. The image forming apparatuses are connected in series in a paper conveyance direction, and include first and second image forming apparatuses. The second image forming apparatus is disposed downstream of the first image forming apparatus in the paper conveyance direction. The determining unit determines whether image data is front-side data or back-side data at a time of duplex printing. The control unit controls the first image forming apparatus to print an image based on the back-side data, and controls the second image forming apparatus to print an image based on the front-side data.

Abstract: In accordance with one embodiment, a duplex printer apparatus comprises a first printing section configured to use an inkjet mechanism for carrying out printing on a first surface of a paper wound in a roll shape; a second printing section configured to be arranged at the downstream side of the first printing section in a paper conveyance direction and use a thermal printing mechanism for carrying out printing on a second surface serving as the back side of the first surface of the paper; and a heat amount changing section configured to change, according to the difference of printing by the first printing section, a driving condition of the thermal printing mechanism when the second printing section applies heat to a paper.

Abstract: A printer includes a recording unit that executes on a recording medium, a recording operation under a sublimation transfer scheme; a conveying unit that using a protrusion roller having protrusions protruding toward an outer periphery and abutting a first surface of the recording medium, conveys the recording medium to a recording position for the recording operation; a pseudo recorded image data producing unit that produces pseudo recorded image data that includes pseudo pixels obtained by correcting a density of each predetermined pixel that is determined corresponding to an arrangement pattern of the protrusions on the protrusion roller and is determined from among pixels to be recorded in a second area that excludes a first area that is in contact with the protrusions, on the first surface of the conveyed recording medium; and a recording control unit that controls the recording unit based on the pseudo recorded image data.

Abstract: A printer having a ribbon heated by energization of a thermal head to transfer color ink and transparent laminate material from the ribbon to a recording medium. The printer includes a first storage section configured to store ink energization data, a second storage section configured to store laminate energization data an energization controlling section, and a correction section that corrects the laminate energization data in response to a residual heat quantity of the thermal head after the ink is thermally transferred in accordance with stored ink energization data and corrects the laminate energization data.

Abstract: A thermal printer includes a thermal head and a control unit that controls energization of each of a plurality of heater elements based on printing data including a plurality of line data arrays corresponding to the plurality of heater elements respectively, for selectively heating up the plurality of heater elements, and performs printing according to an order at the printing data while taking a line data array as a basic unit, on each printing cycle including a heating period and a non-heating period. The control unit delays a start of a heating period in a printing cycle with respect to a start of the printing cycle for a predetermined time period when a predetermined condition with respect to the line data array is satisfied.

Abstract: A method for controlling a printing speed of a thermal head having a plurality of heater elements arranged in a line includes: dividing a set of printing data into blocks each comprising one or more printing lines aligned in a main scanning direction, in which the dividing is in a sub scanning direction, and in which a block including a first predetermined number of printing lines is regarded as a unit block; calculating the number of the heater elements to be driven for each of printing lines included in a block as the number of on-dots, and comparing the numbers of on-dots for the block to obtain a maximum number of on-dots for the block; and setting a printing speed for one block to be slower than a printing speed for another block with smaller maximum number of on-dots than maximum number of on-dots for the one block.

Abstract: A printer having a ribbon heated by energization of a thermal head to transfer color ink and transparent laminate material from the ribbon to a recording medium. The printer includes a first storage section configured to store ink energization data, a second storage section configured to store laminate energization data an energization controlling section, and a correction section that corrects the laminate energization data in response to a residual heat quantity of the thermal head after the ink is thermally transferred in accordance with stored ink energization data and corrects the laminate energization data.

Abstract: A print-dot counting section counts a number of print dots of print data. An adjusting section adjusts to reduce, according to the number of print dots counted by the print-dot counting section, one of conveying speed of a print medium by a conveying unit and energization time of energization to heat generating elements for forming one dot on the print medium and adjusts to reduce the other when the one reaches a lower limit value in an adjustable range. The conveying unit and a thermal head are driven by using the conveying speed and the energization time adjusted in this way to perform printing on the print medium.

Abstract: A method of forming a latent image portion on an overcoat layer by a difference in surface brilliance, at the time of layering an overcoat layer on a thermal transfer subject sheet by a heat transfer method, includes the steps of: setting at least two types of applied energy from the thermal head wherein a plurality of thermal elements are arrayed in line form, and layering the overcoat layer on the thermal transfer subject sheet; forming a difference in surface brilliance made up of a region of relatively high degree of brilliance and a region of relatively low degree of brilliance, based on the difference in the applied energy, to form a line pattern with a plurality of lines; and forming the lines by shifting a phase of a line pattern of the latent image portion and the line pattern of a background portion excluding the latent image portion.

Abstract: A printing apparatus includes a thermal head in which a plurality of heating elements are provided in a width direction of paper, an analyzing unit which analyzes whether an input print layout contains any bar code, a calculating unit which calculates a print ratio of a bar code portion in the paper for each line of the print layout in the case where the analyzing unit analyzes that at least the print layout contains a bar code, a setting unit which sets a printing velocity corresponding to the print ratio for one line in the bar code portion calculated by the calculating unit in the case where the analyzing unit analyzes that the print layout contains the bar code and a changing unit which changes a velocity at which the thermal head performs printing on the paper for one line to the printing velocity set by the setting unit.

Abstract: An apparatus for vacuum bonding a liquid crystal display device includes a unitary vacuum processing chamber, upper and lower stages provided at upper and lower spaces within the vacuum processing chamber for receiving first and second substrates, and at least one first substrate receiving system provided within the vacuum chamber to contact dummy areas between cell areas of one of the first and second substrates.

Abstract: A first thermal head that comes into contact with a front surface of a thermal paper sheet, and a second thermal head that comes into contact with a rear surface of the thermal paper sheet are provided. Further, forward printing and backward printing of the first thermal head with respect to the front surface of the thermal paper sheet are selectively controlled. Furthermore, forward printing and backward printing of the thermal head with respect to the rear surface of the thermal paper sheet are selectively controlled.

Abstract: Apparatus and methods for two-sided direct thermal printing are disclosed. In one embodiment, a dual-sided direct thermal printer comprising a first thermal print head and a second thermal print head is provided wherein a surface of the first thermal print head acts as a platen for the second thermal print head.

Abstract: A method and apparatus for transferring an image of predetermined length onto a substrate by selective energisation of a row of printing elements in a printhead of a printing apparatus. The printing apparatus may be arranged with a print ribbon located between the printhead and the substrate such that ink is selectively transferred from the ribbon to the substrate as a result of energisations of the printing elements. The image to be printed is rendered in memory as a series of rows of pixels and the apparatus is set up to download the rendered rows of pixels to the printhead successively. The relative positioning of successively printed rows of pixels on the substrate is determined by relative displacement between the printhead and the substrate. The apparatus is set up to control the positioning of the rows of pixels by controlling the delay between successive energisations of the printing elements.

Abstract: A first thermal head that comes into contact with a front surface of a thermal paper sheet, and a second thermal head that comes into contact with a rear surface of the thermal paper sheet are provided. Further, forward printing and backward printing of the first thermal head with respect to the front surface of the thermal paper sheet are selectively controlled. Furthermore, forward printing and backward printing of the thermal head with respect to the rear surface of the thermal paper sheet are selectively controlled.

Abstract: A thermal paper sheet having heat-sensitive layers on a first surface and a second surface having a front-and-rear relationship is prepared. A first thermal head which comes into contact with a front surface of this thermal paper sheet and a second thermal head which comes into contact with a rear surface 1b of the same are provided. Further, printing data input from the outside is divided into first printing data and second printing data. The thermal heads are driven in accordance with the printing data.

Abstract: Apparatus and methods for two-sided direct thermal printing are disclosed. In one embodiment, a dual-sided direct thermal printer comprising a first thermal print head and a second thermal print head is provided wherein a surface of the first thermal print head acts as a platen for the second thermal print head.

Abstract: A sensor system for detecting skew in print media along the feed path of a hardcopy device is disclosed. In one embodiment of the invention the system is arranged to generate a first image of a portion of print media at a first position along the feed path and to generate a second image of the portion of print media at a second position along the feed path, the system is arranged to compare the first and second images and thereby detect a change in the angle of skew of the media between the first and second positions.

Abstract: A thermal master making device and a thermal printer including the same are disclosed. A thermistor senses ambient temperature around a thermal head. A correcting device corrects the amount of heat to be generated by the thermal head, i.e., the duration of energization at least two times during a single master making operation. This configuration reduces a change in the perforation conditions of a thermosensitive medium ascribable to the heat accumulation characteristic of the head. The printer achieves high resolution, high-speed master making and space saving.

Abstract: By making judgment whether number of dots to be printed in one printing scan exceeds a predetermined criterion or not, printing elements associated with summing of number of dots are selected if the number of dots exceeds the predetermined criterion, printing scan for the scanning lines corresponding to the selected printing elements is performed, and paper feeding for the printed scanning line is performed. By this, possible largest number of scanning lines can be printed within an allowable electric energy consumption for one scan. Thus, efficient printing operation can be performed.

Abstract: A thermal master making device and a thermal printer including the same are disclosed. A thermistor senses ambient temperature around a thermal head. A correcting device corrects the amount of heat to be generated by the thermal head, i.e., the duration of energization at least two times during a single master making operation. This configuration reduces a change in the perforation conditions of a thermosensitive medium ascribable to the heat accumulation characteristic of the head. The printer achieves high resolution, high-speed master making and space saving.

Abstract: An ink-jet printer includes a nozzle driving unit selectively driving a plurality nozzles to discharge ink through the nozzles, a signal supply supplying a driving signal to the nozzle driving unit, a shift register storing a nozzle selection signal to select a nozzle after the nozzle selection signal is synchronized with a clock signal, a counter counting an input number of the clock signal and deciding whether to operate the shift register, and a controller inputting a discharge signal into the signal supply to discharge the ink when the shift register is disabled. The counter compares a set-up value set up in accordance with a bit number of the nozzle selection data signal with the input number of the clock signal to disable the shift register. Therefore, noise introduced into the noise selection signal by the discharge signal is eliminated. Thus a malfunction of the head driving device can be prevented.

Abstract: A method is provided for providing the same amount of energy to each print head element in a thermal printer during each print head cycle used to print an image, regardless of the number of print head elements that are active during each print head cycle. The desired amount of energy may be provided to a plurality of print head elements that are active during a print head cycle by delivering power to the plurality of print head elements for a period of time whose duration is based in part on the number of active print head elements. The period of time may be a portion of the print head cycle.

Abstract: Circuit board 10 is of substantially rectangular shape, provided in the upper half of the juxtaposed face 13 with a substantially circular test terminal 20. In the lower half are provided a plurality of substantially rectangular terminals 21-27, arrayed in two rows, i.e., an upper and lower row, the upper row containing an I/O terminal 21 for data input/output, a power supply terminal 22 for supplying power, and a chip select terminal 23 for input of a chip select signal CS. The lower row of juxtaposed face 13 contains a ground terminal 24, a read/write terminal 25 for inputting read/write control signals W/R, a clock terminal 26 for inputting a clock signal CLK, and a ground terminal 27.

Abstract: A method and an apparatus for limiting the peak power consumed by a thermal recorder connected to portable battery-powered equipment. The battery-powered equipment is designed with a filter and an electronic circuit breaker. A circuit breaker current sense resistor and an output capacitor form an RC filter and provide a large current reservoir for the thermal recorder which averages the peak current demands seen at the circuit input. The electronic circuit breaker provides a current limit function and will not allow a current greater than a predetermined amperage level to be drawn. The thermal recorder has a CPU which provides pulses to a thermal print head in dependence on data incorporated in a pulse-width limit table. The values in the pulse-width limit table can be substituted for calculated pulse widths that would produce peak currents large enough to trip the circuit breaker.

Abstract: Disclosed is a method of operating an inkjet printer having one or more inkjet print cartridges installed in the printer, wherein the printer is capable of operating under varying operating conditions and in a plurality of different printmodes, including obtaining a value for the common parasitic resistances and a base operating voltage setting for the inkjet printer when a predetermined number of possible resistors on the print cartridge are firing during a given period of time, determining an actual number of resistors firing on the print cartridge during the given period of time, adjusting the base operating voltage setting to a selected voltage setting based on the results of said obtaining step and said determining step and operating the printer using the selected operating voltage setting for the print cartridge.

Abstract: An electrocoagulation printing apparatus has a printing head with an array of electrodes in contact with an electrically conductive electrocoagulation printing ink, and a driver circuit for impressing electric signals to individual electrodes of the array. The driver circuit includes a current limiter for limiting the magnitude of electric current passing through individual electrodes and the electrocoagulation printing ink to a predetermined value. The current limiter corrects a density of adjacent ink film pixels of a printed line to compensate for a cross-influence of impedance between adjacent ink film pixels.

Abstract: A printing apparatus and a printing registration method permits printing registration between a forward and a reverse scan of a head cartridge between a plurality of head cartridges without troubling a user and simply. By forward and reverse scan of the head cartridge, a plurality of patterns, in which a print start timing of the reverse scan is shifted per a predetermined amount relative to that of the forward scan, are printed. These patterns may vary an area factor by the dots formed by printing depending upon offset amount. On the other hand, the plurality of patterns are optically read an average density. By this, the timing, at which the read average density is maximum is set as the printing registration condition.

Abstract: In an inventive method of driving a thermal head including heating resistors corresponding to a line of dots, the heating resistors are grouped into blocks consisting of the same number of heating resistors. After producing main printing data for one line of printing, such blocks where the ratio of the number of heating resistors in which the printing data is inputted to the number of all the heating resistors in each block is smaller than a preset ratio, are detected as target blocks. Then, auxiliary printing data for preheating such heating resistors in each target block to which the main printing data is inputted, is produced. When the total number of the heating resistors in all the blocks to which the main printing data is inputted is larger than a preset number, the auxiliary strobe signal is inputted to the heating resistors to preheat the heating resistors in the target blocks. By this preheating, the shortage of energy due to voltage drop of a power source will be compensated.

Abstract: The improved thermal image recording method for forming an image to be recorded corresponding to image data on a thermal recording material using a thermal head, includes the steps of dividing the image to be recorded on one screen into a specified number of regions each having a specified number of pixels and calculating for each of the regions a representative value of the image data within that region; calculating a predicted value of temperature for each of the regions from the representative value of the image data within that region and an initial value of temperature as detected with a specified number of thermistors; calculating a value of temperature correction for each of the regions from the predicted value of temperature for that region; interpolating the values of temperature correction for the regions to calculate a value of temperature correction for each of the pixels in the image to be recorded on one screen; and performing temperature compensation on the image data of each of the pixels.

Abstract: A thermal printing method using a printing head (6, 20) with a plurality of resistive points (P.sub.i) activated by the pulses of a supply voltage (Va) that fluctuates (.DELTA.V) depending on the number (N) of simultaneously activated resistive points (P.sub.i). The activation of the resistive points (P.sub.i) is controlled by a control signal (STRB) with a duration determined so that the energy (e) delivered to the resistive points (P.sub.i) by each pulse is unaffected by the fluctuations (.DELTA.V) of the supply voltage (Va). The control signal (STRB) includes a first pulse (STRA) with a fixed, predetermined duration (To), followed by a second pulse (STRA+) with a variable duration (t), the duration (t) of the second pulse (STRA+) being determined during the duration (To) of the first pulse (STRA) depending on the actual value (V) of the supply voltage (Va).

Abstract: A multilevel image recording method is provided which can reproduce high resolution images with high quality and at a linear gradation. One pixel is formed by a left dot and a right dot, and a density of the pixel is expressed by a sum total of surface areas of each dot. The density of the pixel is distributed to the left dot and the right dot in accordance with curve A or curve B. At least dots expressing maximum densities at respective pixels in halftone regions are right dots.

Abstract: A thermal printer for forming an image on a sheet includes a thermal head having a plurality of linearly arranged thermal elements. A total number of thermal elements to be energized to form the line image is determined. A difference between the total thermal elements to be energized to form the line image, and previous number of the thermal elements that were energized to form a previous line image is calculated. The thermal elements are then driven for a period of time which is a function of the difference between the total number and the previous number that was calculated.

Abstract: In the disclosed thermal gradation printing apparatus, heat elements in a line-type thermal head are divided into a plurality of groups, and an accumulated heat amount in the substrate of the thermal head for each group is estimated based on the pulse width data applied to each heat element considering the influences by heat accumulations in the main-scanning direction and in the sub-scanning direction. Based on the group division estimated accumulated heat amounts and the temperature of the body portion of the thermal head, a correction value for the pulse width data to be applied to each heat element. Moreover, the correction value is applied to the pulse width data for each heat element, so as to output the corrected pulse width data to the thermal head.

Abstract: Thermal recording comprising the steps of supplying input data I.sub.u to a processing unit (23) of a printer having a thermal head with a plurality of heating elements; storing input data of a line into a buffer memory (24), further called input line data I.sub.l ; converting (25) the data I.sub.l into serial configurated data I.sub.s ; mapping (32) the data I.sub.s with resistance compensation data into power mapped data I.sub.m ; shifting the data I.sub.m into a shift buffer memory (26), further called shifted power mapped data I.sub.m' ; counting (33) a number N.sub.s,on of simultaneously activated heating elements; adapting (34) a strobe duty cycle .delta. (35) in accordance with N.sub.s,on, further called voltage corrected strobe duty cycle .delta..sub.v ; providing (36) the .delta..sub.v and the data I.sub.m' to the heating elements for reproducing the line of an image.

Abstract: By counting the number of thermal printer head elements to be energized for each gradation, and adjusting the energizing period on the basis of the counted number, a common energizing period is obtained in order to prevent density unevenness which would otherwise occur because of differences in the number of head elements to be energized for each gradation.

Abstract: A thermal printer for forming an image on a sheet, with the image having a plurality of line image data. The thermal printer includes a thermal head having a plurality of linearly arranged thermal elements for forming the image. The total number of the thermal elements to be driven is determined. The thermal elements are driven for a predetermined time period in accordance with the line image data if the number of thermal elements to be driven is not greater than a predetermined value. If the total number of the thermal elements to be driven is greater than the predetermined value, then the predetermined time period is divided into a number of fractional time periods and the thermal elements are intermittently driven for each of the fractional time periods. The predetermined value is determined to avoid sticking between the thermal head and a thermosensitive sheet due to excess heat.

Abstract: A portable printer forms a portion of an image in accordance with image data. A built-in battery provides energy to form the portion of the image. The portable printer predicts whether a remaining capacity of the battery, after the portion of the image has been formed, will be larger than a predetermined reference termination value. The portion of the image is not formed if the remaining capacity of the battery is predicted to be less than the predetermined value.

Abstract: In thermal inkjet printing, an energy source supplies voltage pulses to a set of resistors in a printhead. The resistors are not necessarily equal-valued. The subset of energized resistors changes from pulse to pulse as a function of the printable data. As the subsets vary, resulting in a varying load on the energy source, this causes undesirable variations in the energy supplied to individual resistors, even when a regulated source is used, because of residual impedances in the source and wiring. The invention compensates for such energy variations, using information about which subset of resistors is to be energized during a pulse. By determining the electrical load presented by the subset, and by referring to a predetermined relation between the load value and the voltage drop in the residual impedances, the invention maintains nominally constant energy in individual pulsed resistors by an appropriate adjustment of the pulse width.

Abstract: A thermal printer for forming an image on a sheet includes a thermal head having a plurality of linearly arranged thermal elements. A number of thermal elements to be driven to form a line image is determined. A time period that the thermal elements are to be driven to form the current line image is then calculated in accordance with a number of thermal elements driven to form a previous line image and the number of thermal elements determined to be driven to form the current line image. The thermal elements are then driven for the calculated time period to form the current line image.

Abstract: In the disclosed thermal gradation printing apparatus, heat elements in a line-type thermal head are divided into a plurality of groups, and an accumulated heat amount in the substrate of the thermal head for each group is estimated based on the pulse width data applied to each heat element considering the influences by heat accumulations in the main-scanning direction and in the sub-scanning direction. Based on the group division estimated accumulated heat amounts and the temperature of the body portion of the thermal head, a correction value for the pulse width data to be applied to each heat element. Moreover, the correction value is applied to the pulse width data for each heat element, so as to output the corrected pulse width data to the thermal head.

Abstract: A thermal transfer recording apparatus for performing the recording an image on a recording medium by transferring ink contained in an ink sheet to the recording medium has ink sheet a conveyance unit for conveying the ink sheet, a recording medium conveyance unit for conveying the recording medium, a recording unit for recording an image on the recording medium by activating the ink sheet, a counting unit for counting the black dot numbers in the current line, a timing unit for measuring the elapsed time since the image recording in the last line by the recording unit, and a control unit for controlling the ink sheet to be conveyed for a predetermined length without conveying the recording medium in accordance with the timing value of the timing unit and the counting value of the counting unit subsequent to the current line recording by the recording, thus making it possible to separate the ink sheet and recording sheet more reliably to maintain a high recording quality.

Abstract: An ETR printing unit has electrodes and an ETR print head. A configuration for triggering the ETR print head includes a controllable energy source supplying energy for various pixels of a printed image to the electrodes of the ETR printing unit. A switching unit is provided through which the controllable energy source acts upon the electrodes temporarily connected to the energy source with a voltage or with a constant current, having a magnitude with a dependency on a temporarily different number of electrodes for supplying a larger number of electrodes with a higher voltage or a higher constant current than a lesser number would be. A microprocessor control unit for the ETR printing unit supplies the controllable energy source with a control signal corresponding to a dependency on the number of the triggered electrodes, for specifying the number of electrodes temporarily connected to the controllable energy source. A memory is connected to the microprocessor control unit.