Abstract: A fluorescent print head driving method is provided wherein an operational lifetime is improved by reducing the evaporation amount of Ba contained in an electron emitter material of a filament cathode and suppressing the deterioration of the luminous efficiency. In the pre-luminous period T1 during which luminous dots glow before forming an image on a recording medium, a grid voltage is controlled to be a predetermined voltage of a rated value or less and a filament voltage is controlled to a predetermined voltage of a rated value or less. In the print luminous period T2 during which luminous dots glow before forming an image on a recording medium, a grid voltage blank period is created corresponding to a luminous blank period between glow states during which an anode voltage is written for one line on the recording medium. The anode voltage and the grid voltage are controlled to be a rated voltage with a duty ratio corresponding to a blank period.

Abstract: A semiconductor laser driving apparatus has a laser diode that emits a laser beam, a laser driving circuit that drives the laser diode by feeding a driving current in pulses to the laser diode, a conductor that conducts the driving current from the laser driving circuit to the laser diode, and an inductance adjuster that has a conductor-pattern for conducting the driving current and adjusting the magnitude of inductance in the conductor. A part of the conductor-pattern that makes the magnitude of the inductance a proper magnitude for emitting the laser beam in generally rectangular pulses, is selectively defined and conducts the driving current as a part of the conductor.

Abstract: A laser marking system includes a high power fiber laser with a double clad fiber having a doped core surrounded by an inner pump cladding and providing an optical output for marking; a high power laser diode source for pumping the double clad fiber laser via an input into the inner pump cladding; an optical scanner coupled to receive the marking output from the double clad fiber laser to scan the output over a surface of an article to be marked by sweeping the marking output in one, two or three dimensions to form strokes, the completion of which comprises indicia to be marked on the article surface; and a controller to control the operation of the scanner synchronized with the modulation of the laser diode pump source to initiate the marking output and sweep and modulate the marking optical output in one, two or three dimensions to form strokes comprising the indicia.

Abstract: A method of driving a laser device in an electrophotographic machine includes providing a binary image data signal having a first switching rate. A plurality of binary encoded data signals are transmitted over a transmission medium. Each of the encoded data signals is dependent upon the image data signal and has a respective second switching rate lower than the first switching rate. The image data signal is recreated by using the encoded data signals. The laser device is driven with the recreated image data signal.

Abstract: A self-scanning light-emitting device is provided in which the number of bonding pads can be decreased, i.e. 2 or 3. The device comprises an array of a plurality of three-terminal light-emitting elements; electrical means having unidirectional characteristic to voltage or current for connecting the control electrodes of neighboring light-emitting elements to each other; two clock pulse lines for applying two-phase clock pulses alternately to one of two terminals except the control electrode of each light-emitting element; and a power supply line connected to each of the control electrodes of the light-emitting elements via a load resistor, respectively. The resistance of the load resistor connected to the light-emitting element to be turned on at first is selected to be smaller than that of other resistors. As a result, the bonding pad for the start pulse may be omitted.

Abstract: Methods of providing lower resolution format data into higher resolution format are described. A laser printing system is provided having first and second lasers configured to receive and be driven by raster data. Image data, which is to be rendered onto a print medium is received in a first resolution format. The first resolution format is converted into a second resolution format which is greater than the first resolution format by mapping the image data to provide mapped image raster data in the second resolution format. The first laser is driven with a portion of the mapped image raster data, and the second laser is driven with another portion of the mapped image raster data.

Abstract: A print head has driver circuitry that dynamically drives a row of driven elements, such as light-emitting elements, by driving different combinations of first and second terminals. The print head includes memory circuits storing compensation data for the driven elements, and multiplexing circuits that select the compensation data according to the combination of terminals being driven, thereby enabling the compensation data to be stored in the print head despite the use of dynamic driving. The compensation data are used in adjusting the amount of energy supplied to the driven elements. The amount of compensation data to be stored may be reduced by sharing the upper bits of the compensation data among a group of driven elements.

Abstract: A laser diode in a recorder is thermally stabilized. The laser diode is used to produce a light beam, which is modulated by superimposing a basic current and a modulation current derived from an image signal, and exposes a recording material point by point and line by line. Between the exposure periods, wherein in each case one line is exposed, there are return periods, wherein the light beam is guided to the start of the next line, and wherein the laser diode is modulated for the purpose of thermal stabilization. In the return period, the laser diode is modulated with the basic current during a stabilization period, the sum of the modulation times during the exposure period and during the stabilization period being constant. In addition, during the return period, the laser diode can be modulated with a modulation current, which is derived from the inverted image signal from the preceding or the following line.

Abstract: In an image forming apparatus, an image forming section forms an entire object image using at least two dot-sequence forming units. At that time, at least two image quality control sections corresponding to the respective dot-sequence forming units control an actual-image forming state of each of dots of the object image. A buffer section has a predetermined number of line-data buffers each for storing the line data of an individual line of image data received from the image-forming request source for temporary retention and is shared by the plural image quality control sections. In the meantime a data-store-and-read control section controls a data store operation and a data readout operation so as to execute the two operations in parallel.

Abstract: A drive IC chip (A) has a primary surface (10) which includes a corner (11a) at which a first and a second pads (3a, 3b) are provided so that their respective centers (Oa, Ob) are deviate positionally from each other in both directions x, y. With this structure, even if two wires for electric connection are extended from the first and the second pads (3a, 3b) either in the x direction or in the y direction, it is possible to advantageously prevent the wires from becoming too close to each other into shorting contact.

Abstract: The formation of a high-quality image at a resolution at which a dot size is smaller than the diameter of a laser beam is attained at a low cost. When an exposure operation is carried out by increasing an optical intensity of a laser beam to a level higher than that of a steady-state optical intensity thereof by utilizing a difference, which is ascribed to an exposure rate of a photosensitive body, in the condition of a latent image formed, the depth and width of a latent image, which were small in all related art cases, can be increased to high levels. Therefore, overshoot is generated at the LD lighting starting time to increase the optical intensity at a rising edge of the laser beam to a level higher than that of a steady-state optical intensity thereof, whereby a height to width ratio and the reproducibility of one dot and a halftone in a case where the resolution is smaller than the diameter of the laser beam can be improved.

Abstract: A device for spotwise imaging printing surfaces includes a laser light source producing at least one laser beam movable relative to a printing surface, the laser beam defining an image spot on the printing surface, the laser beam having a laser power. A laser control varies the laser power or an exposure time as a function of a distance of the laser light source from the image spot.

Abstract: A pulse emitting laser is constantly controlled while recording data continuously to a desired power level without using test emissions or a high speed sample hold filter. The laser drive method detects beam emission power from a light source and generates a monitor wave; receives data and generates an expected wave for the beam power based on the received data; calculates the difference between the generated monitor wave and the expected wave; controls current flow from the bias current source based on the calculated waveform difference; and finally emits a beam from the light source based on the controlled current flow of the bias current source.

Abstract: A variable resolution transition placement circuit in an electrophotographic imaging device allows transitions to be placed within a stream of video data so that the pixel resolution achieved over a scan line is adjustable on a pixel by pixel basis using a system clock. Pixel data defines transition positions relative to a synthesized video clock defining pixel time periods. A converter converts positions of the transitions relative to the synthesized video clock to positions relative to the system clock using a value provided by a synthesized video clock to system clock transform generator. The value can change between synthesized video clock cycles to change the pixel resolution. A synthesized video generator generates values of a synthesized video clock relative to the system clock.

Abstract: The present disclosure describes techniques that can be used to reduce the time required for a printer or printing system to generate printed output. Printers are provided that operate to move from an idle mode into a print mode upon receiving a PRE-START signal. Printers are also provided that operate to remain in a print mode for an extended period of time upon receiving a PRE-START signal. The PRE-START signal is a signal that indicates one or more “pre-print”acts have been performed. In addition, printing systems are provided that include peripheral devices adapted to transmit a PRE-START signal to a printer upon the detection of one or more PRE-PRINT acts.

Abstract: An image forming system is provided with an image memory for storing a number of frame images, a composite image generator for generating a composite image bearing frame images, and a composite image recorder for recording generated composite image on a recording medium having a base layer, an adhesive layer, and a recording layer. The system is further provided with a separation former for forming a perforation line on the recording medium for dividing a specified frame image from the other frame image.

Abstract: Methods of providing lower resolution format data into higher resolution format are described. In one embodiment a first predetermined amount of image data is provided which is to be rendered onto a print medium. The first predetermined amount of image data is provided in a first resolution format. Using the first predetermined amount of image data, the first predetermined amount of image data is replicated into multiple predetermined amounts of data sufficient to provide said first predetermined amount of image data into a second resolution format which is greater than the first resolution format. At least one laser beam in a laser printer system is modulated using the multiple predetermined amounts of data.

Abstract: An optical shutter is provided in the middle of a triopical path of the recording laser. Before a recording operation of data such as the images and the characters, the optical shutter is closed and also a recording laser light is outputted from the LD at a predetermined output rate. Then, immediately before the recording start of the data, the output of the recording laser is interrupted and also the optical shutter is opened, and then the recording of the data is started. Accordingly, there can be provided the image recording apparatus which is able to set the recording laser into its stabilized output state to record immediately after the recording start and to prevent generation of the irregularity of the images, the unevenness of the line width, etc.

Abstract: Raster scanners, and printing machines which use raster scanners, that include compensation for the finite response times of their lasers and their laser drive signals on image edges. When an image pixel is not an image edge the laser driver is driven in synchronization with a master clock. However, if an image pixel is an edge of an image the laser driver is driven earlier than it would have been if it was driven in synchronization with the master clock. Beneficially, the drive to the laser driver is advanced such that the actual laser exposure curve crosses that of an ideal laser exposure curve such that the developed line edge is substantially ideal.

Abstract: A recording head includes a recording element array including a plurality of linearly arranged recording elements, and a flexible wiring substrate for inputting a recording signal into the recording element array. A matrix-wiring for matrix-driving the plurality of recording elements is formed in the flexible wiring substrate.

Abstract: An image forming apparatus wherein data which enters in parallel a plurality of pixels at a time is converted to a serial image data string. This serial image data string is shifted by a predetermined number of pixels, the shifted serial image data string is output in parallel a plurality of pixels at a time, and an image is formed based upon the image data output in parallel a plurality of pixels at a time.

Abstract: A driving current is supplied via a current limiting resistor to a laser diode for emitting a red laser beam. This driving current is controlled so as to make the optical output of the laser diode have a predetermined reference value. Further, a current of a constant level is intermittently subtracted from the driving current flowing into the laser diode, on the basis of an image to be formed.

Abstract: Double clad fiber gain medium systems particularly adapted for marking indicia on surfaces of articles are disclosed. These systems provide a modulated output from a pump or seed semiconductor laser source to a double clad fiber gain medium which provides an amplified marking output scanned over the article surface with an optical scanner forming a plurality of strokes, the completion of which results in the indicia.

Abstract: A head controller 2 reads out adjustment data from a ROM 3 immediately after a power-on operation. The adjustment data is prepared for adjusting unevenness of light emission from LEDs in a LED head 5. A buffer memory 4 stores the read adjustment data. The head controller 2 reads the adjustment data from the buffer memory 4 with high data transfer rate, and obtains bitmap data from a frame memory or the like (not shown). The head controller 2 sends the read bitmap data and the adjustment data to an anode driver 51. The head controller 2 sends a strobe signal to the anode driver 51 and a cathode driver 53. The anode driver 51 adjusts ampere of supplied currents (i.e. drive signals corresponding to the bitmap data) from the head controller 2, in accordance with the received adjustment data in response to the reception of the strobe signal. The adjusted drive signals are sent to LED array chips 52.

Abstract: An image formation apparatus which records an image on a recording medium is provided. The apparatus has a recording element array head on which plural recording chips are arranged, plural recording elements being arrayed on the recording chip, a reference clock generation unit for generating a reference clock, a main scan sync signal generation unit for generating a main scan sync signal by dividing the reference clock into 2n1 (n1: positive number) parts, an input unit for raster inputting image data for one line in synchronism with the main scan sync signal, a drive clock generation unit for generating a drive clock by dividing the reference clock into 2n2 (n2: positive number) parts and a drive unit for driving the recording chips in synchronism with the drive clock.

Abstract: An image formation apparatus stably controls a drive current of a laser diode irrespective of change in density. In the apparatus, a current restriction circuit restricts a current ILD according to the output light quantity. If the current ILD increases and thus approaches to the value of a reference current IPO, the circuit outputs the current restricted to be the certain value substantially equal to the current IPO. Then, current buffers and, a current subtraction circuit, a switching circuit and a current addition circuit cooperatively supply the function current obtained from the input and output currents of the circuit to the cathode of the laser diode.

Abstract: A method and apparatus for a fault tolerant recording system using a pair of laser diode arrays is disclosed. Two monolithic laser diode arrays made of individually addressable diodes are used to record parallel tracks on a recording surface. A pair diodes, (one diode from each array) are assigned to each track, but only one diode (the primary diode) is activated. In the case where the primary diode fails, the secondary diode is activated. Digital delays are employed to synchronize the data from the two diode arrays in order to align the written marks on the recording surface.

Abstract: An optical scanning device is provided with a light source that emits a light beam, a driver that controls output power and modulation of the light beam emitted by the light source, a controller that transmits, to the driver, power control data and modulation data respectively used for controlling the output power and modulation of the light beam. The optical scanning device is further provided with a single data bus that connects the driver and the controller. The power control data and the modulation data being transmitted through the single data bus at different timing.

Abstract: In order to realize edge smoothing in an image printing apparatus using a plurality of laser beams, commonality of a data processing circuit to the plurality of laser beams is attained by obtaining image data for the plurality of scanning lines in synchronism with a common scanning position of one of the plurality of laser beams and storing the image data into a common memory and generating laser modulating data for each of the laser beams; temporarily the laser modulating data for the other laser beams into FIFOS; using the laser modulating data in synchronism with the respective scanning positions of the plurality of laser beams to generate laser modulating signals for the respective laser beams in a PWM.

Abstract: The present invention provides an exposure device capable of operating at a high speed and obtaining an excellent printing result. The exposure device according to the present invention includes optical write heads using shift registers of two systems, and a circuit that supplies image data for one line divided into the first half and the second half to the respective shift registers. The circuit is consist of a write control section, a memory, a read control section and a transfer control section), and receives data of twice the number of bits of data inputted to the shift register.

Abstract: In an electrophotographic image formation, a driving current for laser emission is pulse-width-modulated in correspondence with externally input image data. The pulse width modulation of the driving current is started after a predetermined time period has passed from a time point of beam detection by a light detector located at a position leading a photosensitive drum in a main scanning direction. The driving current is adjusted in correspondence with the light amount detected. Current adjustment data is supplied to a current modulation circuit in the same manner as image data. Detection is made of the laser beam, which is pulse-width-modulated by the current modulation circuit on the basis of the supplied adjustment data, and is emitted from the laser light source, by a laser monitor device under control of a monitor controller.

Abstract: A laser imaging system having a diode laser for producing a laser beam; a beamsplitter for splitting the laser beam into a laser writing portion and a feedback portion; a photodetector for detecting the feedback portion; a photodetector amplifier for amplifying the output of the photodetector; a sample and hold coupled to the photodetector amplifier; an integrator adder; an integrator for integrating the outputs of the photodetector amplifier and the sample and hold processed by the integrator adder; and a laser input circuit including a laser amplifier, a linear power signal provider, a threshold power signal provider, and a laser input adder for adding the laser power signal, the linear power signal, and the output of the integrator.

Abstract: A method for controlling a radiation intensity of a laser beam emitted by a laser having a threshold current level above which the laser emits the laser beam, the method including the steps of: supplying an electrical driving current for driving the laser, the electrical driving current increasing up to about the threshold current level; subsequently immediately further increasing the electrical driving current to a value above the threshold current level for causing the laser to emit the laser beam; and an image exposure device implementing this method.

Abstract: The present invention relates to a pulse generation apparatus for generating a pulse signal having a pulse width controlled, and a pulse signal having a pulse width controlled with high precision is generated by a circuit suitable for conversion into LSI.

Abstract: A first embodiment of an adjustment circuit for a laser diode output power compensator includes a feedback circuit for adjusting the laser diode output power compensator so that the output power of the laser diode is substantially constant. The feedback circuit includes a photodiode for measuring the output power of a VCSEL diode. The signal from the photodiode is coupled to a first amplifier. The difference between the signal from the photodiode and a first reference value is amplified and coupled through electronic switches to selectively charge one of multiple capacitors. The multiple capacitors are each coupled to one of a drive current source, a compensation current source, and a voltage controlled resistor, each of which are voltage controlled. A second amplifier is used for amplifying the difference between the signal from the photodiode and a second reference value to charge a capacitor coupled to a voltage controlled bias current source.

Abstract: In a method of driving a plurality of optical output media aligned in one direction in an optical writing apparatus that drives activation and deactivation of the optical output media based on image data to thereby perform optical writing onto an object onto which writing is to be performed, it is determined whether the number of optical output media that are writing-driven based on the image data in order to perform optical writing onto the object is smaller than the total number of optical output media, and when the number of writing-driven optical output media is smaller than the total number of optical output media, non-writing driving of optical output media other than the writing-driven optical output media is performed. The non-writing driving is a driving in which optical writing is not performed onto the object.

Abstract: Regardless of a relative installation position error between a light source and a photosensitive material, or of a deviation from a properly preset value of rotation speed of a photosensitive material, images are obtained with minimum loss of image quality and excellent reproducibility. The number m of light-emitting elements to make up a unit and the distance between adjacent pixels formed on the photosensitive surface are adjusted such that the width of the pixel groups is ⅓ mm or less, which is a period that the periodic image noise is not recognized as stripes.

Abstract: An image forming apparatus forms an image on a medium by using an output device. A pattern signal for forming a predetermined pattern image on the medium is generated, and image forming parameters for the output device are determined on the basis of the density of the pattern image formed on the medium. The determined image forming parameters are transmitted via bidirectional communication to an external computer or other image forming apparatus.

Abstract: An optical write head operable in high speeds is provided with better printing results. The optical write head is arranged by an LED array constructed of a plurality of LEDs arrayed in a line form, one shift register used to store thereinto pixel data for a front half portion of this LED array, and the other shift register used to store thereinto pixel data for a rear half portion of this LED array. The optical write head is further arranged by registers for latching parallel pixel data outputted from these shift registers, and a driving circuit for simultaneously driving the LEDs employed in the LED array in response to patterns of the pixel data outputted from the registers when a control signal is inputted.

Abstract: A non-impact printer include a print head with a plurality of print elements such as light emitting diodes (LEDs). A driver drives the plurality of LEDs in accordance with logical states of corresponding bits of print data. A non-volatile memory stores energy specifying data. The energy specifying data describes an amount of drive energy that should be supplied to each of the plurality of print elements when each of the plurality of LEDs are driven during the printing. A random number generator generates random numbers. An adder adds the random numbers to the values of the energy specifying data to produce the energy specifying data that fluctuates within a predetermined range. Each of the plurality of LEDs is supplied with an amount of drive energy to in accordance with the fluctuating energy specifying data, thereby rendering the variations in print density of an entire image not detectable.

Abstract: A laser marking system comprises a high power fiber laser consisting of a double clad fiber having a doped core surrounded by an inner pump cladding and providing an optical output for marking; a high power laser diode source for pumping the double clad fiber laser via an input into the inner pump cladding; an optical scanner coupled to receive the marking output from the double clad fiber laser to scan the output over a surface of an article to be marked by sweeping the marking output in one, two or three dimensions to form strokes, the completion of which comprises indicia to be marked the article surface; and a controller to control the operation of the scanner in synchronism with the modulation of the laser diode pump source to initiate the marking output and sweep and modulate the marking optical output in one, two or three dimensions to form strokes comprising the indicia. A main advantage of the fiber laser marking system over CO.sub.

Abstract: In an image forming apparatus for forming an image by scanning a rotating photosensitive member with modulated light based on an image signal, a PLL circuit generates a high-frequency clock having a frequency n (n is an integer that satisfies n>2) times that of an oscillation output from a reference oscillating circuit. A frequency dividing circuit generates an image processing clock synchronized with the high-frequency clock and a detection signal from a scan light detecting mechanism. A latch circuit, a parallel/serial conversion circuit, and the like generate an image modulating signal by modulating image data on the basis of the high-frequency clock.

Abstract: In a laser scanning apparatus having a polygonal mirror, the laser light reflected from the multiple reflecting surfaces of polygonal mirror is detected with a photosensor. The respective detection outputs are stored in associated storage media (sample and hold circuits). When a certain reflecting surface has been rotated to the next laser light scan position, the detection output for the previous laser light scan is read out of the storage medium. A correction voltage is generated on the basis of the thus read detection output and the reference voltage is corrected with the generated correction voltage. Since the emission output of laser diode is controlled on the basis of the corrected reference voltage, the photoreceptor can be scanned with laser light of constant optical intensity despite the variation in the reflectance of laser light among the multiple reflecting surfaces of the polygonal mirror.

Abstract: A method for controlling the intensity of an imaging laser of an electrophotographic device in order to produce both positive and negative output. This is accomplished by using a software controlled digital circuit to increase or decrease the power supplied to the laser based on the user's desire to print positive or negative output. When the user desires to print positive output, the laser is set to full power. When the user selects negative mode printing, the power to the laser is digitally reduced by a factor unique to the electrophotographic characteristics of the printing device.

Abstract: An image forming apparatus and method that provides a laser beam oscillator that provides a laser beam corresponding to an original image, reflects/scans the laser beam, transmits a first part of said laser beam to a photoconductive element to write thereupon an image indicative of the original image, accepts a second part of the laser beam as to control and synchronize a write timing sequence of the laser beam on the image carrying element.

Abstract: An integrating xerographic light emitter array includes circuitry for using organic light emitting diodes (OLEDs) operated at modest light levels to expose a photoreceptor drum or belt. This is accomplished by staging an array of the emitters in the slow scan direction and clocking the data through pixel driving shift registers synchronously with the movement of a photoreceptor past the array in the slow scan direction. Increased emitter lifetime and the ability to operate at lower light levels are achieved in proportion to the number of stages. The method for operating the xerographic light emitter array includes transmitting data signals to the first row pixels, shifting the data signals down the columns synchronously with photoreceptor movement and supplying current to drive the OLEDs. Multicolor devices for xerocolography and tandem or multipass color architectures are straightforward extensions of this design.

Abstract: An image forming apparatus includes reading means for converting image light obtained by optically scanning an original into an electric signal. An image signal conversion table converts the image signal from the reading means in response to a property of the image forming system. An image signal generating device generates a reference image signal, and an image forming device forms an image on a recording sheet in response to the image signal. The image is formed on the recording sheet by the image forming device in response to the image signal generated by the image signal generating device, and image light obtained by optically scanning the recording sheet is converted into an image signal by the reading device, and the image signal conversion table is corrected on the basis of the image signal converted by the reading device.

Abstract: A device for correcting the non-linearity of a scanner comprising: a reset pulse generator for generating a reset pulse with a predetermined pulse width in synchronization with a scanning start signal generated corresponding to an input photosensitive belt sensing signal; an address generator for outputting an address by being reset by the reset pulse; a look-up table, that is initiated by the scanning start signal, for receiving an address from the address generator and for outputting information corresponding to the address in the form of digital data; and a converter for outputting a synchronizing signal with a frequency corresponding to the digital data from the LUT. Another aspect of this invention is a method for correcting the non-linearity of a scanner.

Abstract: A printer includes a photosensitive drum which is exposed by a line head which includes a fluorescent head having a large number of light points which are aligned in a direction of a width of the photosensitive drum, and the respective light points of the fluorescent head are driven by a line driver in accordance with drive data from a shift register which holds the drive data for all the light points. One print line is formed by a set of four sublines. In a case where the thinning of a line width is corrected in a main scanning direction, the print line is formed by sublines more than five, whereby the line width is fatted.

Abstract: A light emitting apparatus including a photosensitive member and an exposure device including a light emitting device array made up of a plurality of light emitting devices arranged in a direction of main scan across a moving direction of the photosensitive member and a switching device array made up of a plurality of switching devices arranged and connected to the light emitting devices in one-to-one relation. The switching device array is divided into a plurality of groups, a first group of leads connected in common to first terminals of the switching devices for each of the plural groups of switching devices, a second group of leads connected to second terminals of each of the switching devices, and a third group of leads, each of the third group of leads connected to third terminals of each switching device in a respective group of switching devices.