Abstract: Light quantity unevenness is corrected at high resolution to improve image quality, without increasing a speed of system clock. Pixel correction data which is to correct a light emission characteristic of each light emission element by the pixel unit is prepared for plural lines, and the pixel correction data for the plural lines are periodically changed to modify a light emission driving time of each light emission element.

Abstract: SLED (Self-scanning type Light Emitting Diode) array chips of 56 pieces and one driving circuit which generates signals to drive the 56 SLED array chips are provided. A signal is generated by another driving circuit. A driving current control resistor which is connected in series to a common base of driving transistors is provided to variably adjust an input voltage value acting as a control signal of the driving circuit. Thus, a light emission array head, a driving level adjustment method of a driving signal for this head, and an image formation apparatus containing this head can be simplified.

Abstract: When pulsewidth modulation is performed with a digital data pattern, appropriate pulsewidth modulation is performed in accordance with variations of a device or a driving system. In a case of inputting data where one pixel is expressed by, e.g., 4 bits (16 tones), a 32-bit pattern having twice as many number of bits as a 16-bit pattern is prepared as a pattern corresponding to input data, and stored in digital data output unit 1001. Pulsewidth addition circuit 1007 is provided for adding a fine-adjustment pulsewidth so as to achieve a target amount of light. The pulsewidth addition circuit 1007 is set so as to achieve a minimum pulsewidth that can generate a laser beam when input data is 0.

Abstract: To prevent an electrical short due to ion movement in a semiconductor chip and improve the reliability. In a predetermined period T2 in which light-emitting or transfer operation is not performed by light-emitting elements, control signals &phgr;1, &phgr;2, &phgr;I, and &phgr;S and a signal &phgr;m of a negative-electrode-side power-supply input unit are set to a potential or high-impedance state same as that of a positive-electrode-side power-supply input unit.

Abstract: Distortion of an LED array head is eliminated by correcting an electrode pitch misalignment between an LED array substrate and a driver substrate to be caused by thermal expansion or contraction during thermal pressure bonding of a flexible cable. A tear preventing hole is formed in each area between adjacent four-divided areas of the flexible cable. When positions of the flexible cable and driver substrate are to be aligned, a pitch shift adjusting slit line is cut in order to correct the position misalignment to be caused by thermal expansion or contraction generated when the flexible cable is thermal-pressure bonded to the LED substrate. The pitch shift adjusting slit line is formed in the connection area between adjacent four-divided areas.

Abstract: To prevent an electrical short due to ion movement in a semiconductor chip and improve the reliability. In a predetermined period T2 in which light-emitting or transfer operation is not performed by light-emitting elements, control signals &phgr;1, &phgr;2, &phgr;I, and &phgr;S and a signal &phgr;m of a negative-electrode-side power-supply input unit are set to a potential or high-impedance state same as that of a positive-electrode-side power-supply input unit.

Abstract: An image formation apparatus which records an image on a recording medium has a recording element array head on which plural recording chips are disposed, and in the recording chip plural recording elements are arrayed. A main scan unit is for scanning the recording elements, and a sub-scan unit, for effecting relative motion between the recording medium and the recording chips in a sub-scanning direction. The main scan unit scans the recording elements n (n≧2) times on the basis of image data corresponding to one scan. The direction along which the recording elements are disposed, is deviated from the direction perpendicular to the sub-scanning direction, by a predetermined angle.

Abstract: When pulsewidth modulation is performed with a digital data pattern, appropriate pulsewidth modulation is performed in accordance with variations of a device or a driving system. In a case of inputting data where one pixel is expressed by, e.g., 4 bits (16 tones), a 32-bit pattern having twice as many number of bits as a 16-bit pattern is prepared as a pattern corresponding to input data, and stored in digital data output unit 1001. Pulsewidth addition circuit 1007 is provided for adding a fine-adjustment pulsewidth so as to achieve a target amount of light. The pulsewidth addition circuit 1007 is set so as to achieve a minimum pulsewidth that can generate a laser beam when input data is 0.

Abstract: There is disclosed an LED array chip which can minimize LED optical property deterioration by addition of a surface protective film, and mainly side effects such as light quantity decrease and light quantity dispersion increase among light emitting bits. In the LED array chip comprising a plurality of LED light emitting elements arrayed in a row, a surface insulating film formed by the same material as a material of an inner-layer insulating film for forming a window to connect a wiring pattern in an internal electric circuit constitution and for establishing electric insulation between circuits and by the same thin film forming process as a process of the inner-layer insulating layer is formed in an thickness of 0.5 &mgr;m or less on the entire surface of a final surface layer excluding a wire bonding pad and including a light emitting portion surface.

Abstract: An LED array head for an electrophotographic system includes a base plate mounting thereon a number of linearly arranged LED chips and a support member holding the base plate. The base plate and the support member are bonded together by means of a principal adhesive agent which is elastic after hardening such as a silicone type and an auxiliary adhesive agent which hardens more quickly and is less elastic after hardening than the principal adhesive agent. An ultraviolet ray setting type adhesive agent is preferably used as the auxiliary adhesive agent. Assembling steps of such LED array heads can proceed without waiting for hardening of the principal adhesive agent.

Abstract: A method and apparatus for reducing image unevenness due to light emission of a transfer element. Namely, when a printing speed is changed to 1/2n (n is a positive integer), a SLED head controller repeats a cycle to perform exposure control for one line and then stops the exposure control for the lines corresponding to 1/2n speed. For example, in the 1/2 speed (i.e., n=1), transfer and light emission driving are performed at an initially set maximum speed, and the cycle when the exposure control for one line is stopped after the one-line exposure control is repeated. The printing speed is changed on the basis of the type or kind of recording medium used.

Abstract: In a drive apparatus of a self-scanning type light emission element array, a first bit light emission thyristor is surely set into an ON state, thereby stabilizing shift of a light emitting operation from the first bit light emission thyristor. In the light emission element array drive apparatus which drives a light emission element array having plural light emission thyristors arranged in array and plural shift thyristors arranged in array (each gate of shift thyristors is connected to each gate of light emission thyristors), the apparatus comprises: a generation unit for generating a shift signal to sequentially shift ON states of the shift thyristors; and a generation unit for generating a start signal to start drive of the light emission element array, wherein a gate voltage of the first light emission thyristor is supplied according to the start signal without setting the first shift thyristor into an ON state according to the shift signal.

Abstract: A communication control system includes a first communication control apparatus connected to one end portion of each of a clock signal line and a data signal line, and a second communication control apparatus connected to the other end portion of each of the clock signal line and the data signal line.

Abstract: A sharp image having excellent color balance is formed by preventing differences in the amount of light among recording heads. When forming an image using at least two recording heads, each having transfer thyristors and light-emitting thyristors arranged in the form of an array, by causing the transfer thyristors of M, C and Y recording heads having light-emitting thyristors not to be lit to perform transfer operations as the transfer thyristors of a K recording head having light-emitting thrystors to be lit, the difference in the amount of light among the recording heads is corrected.

Abstract: An information processing apparatus including a switch for manually requesting change of output image quality, detecting unit for detecting a condition of the apparatus, setting unit of setting an image forming condition in accordance with the detected condition and the requested output image quality and control unit for changing the image forming condition by learning the request previously requested by the user. Image forming conditions are adjusted so as to satisfy the user manually based upon the degree of satisfaction determined by the user.

Abstract: A communicating apparatus for performing a serial communication with a plurality of communication control units which are cascade connected, including a communicating unit for performing a serial communication with each of the communication control units, a storing unit for storing position data indicative of the order of the communication control units which are cascade connected, and a diagnosing unit for diagnosing a communication abnormal portion on the basis of the position data stored in the storing unit. The diagnosing unit executes a predetermined communication with the communication control unit existing at a position that is closest to the communicating apparatus on the basis of the position data stored in the storing unit and performs a diagnosis on the basis of a result of the predetermined communication. The communicating unit transmits address data to designate the communication control unit to be communicated.

Abstract: A communication control system includes a first communication control apparatus connected to one end portion of each of a clock signal line and a data signal line, and a second communication control apparatus connected to the other end portion of each of the clock signal line and the data signal line.

Abstract: A power circuit includes a transformer having a flyback winding for outputting an energy at an off-time of a primary winding to a secondary circuit a forward winding for outputting an energy at an on-time of the prime winding and a high voltage winding for outputting an energy over an entire period, a first rectifying circuit for rectifying the output of the flyback winding; a second rectifying circuit for rectifying the output of the forward winding, a voltage detection means for detecting the output voltage of the first rectifying circuit, first control means for controlling the on-time of the transformer in accordance with the output of the voltage detection means to control the output voltage of the first rectifying circuit to a predetermined value, and second control means for turning on and off the output voltage of the second rectifying circuit independently from the first control means.

Abstract: An apparatus for operating a fluorescent lamp having first and second power source circuits, the second power source circuit including a high frequency transformer having two or more outputs for supplying pre-heating electric currents to filaments, the second power source circuit being arranged to be controllable individually from the first power source circuit for supplying a tube electric current to turn on a fluorescent lamp so that the electric power level for pre-heating the filaments is switched between a state where a light adjustment is performed by turning on/off a tube electric current at high frequency and a state where the fluorescent lamp is turned off in a standby mode.

Abstract: An AC high-voltage power supply circuit, adapted for use in an image forming apparatus, for example in the separation charger of an electrophotographic copier, and capable of controlling the DC component of an AC high voltage, over a wide range including positive and negative regions. The power supply circuit includes, at the low voltage side of a secondary coil of an AC high-voltage transformer, a DC constant current circuit consisting of a transistor and a diode, a constant voltage circuit opposite in polarity to the DC constant circuit, and a detection circuit for detecting the DC component of a load current. The outputs of the constant voltage circuit and of the DC constant current circuit are controlled according to the output of the detection circuit. Such a device has a simple structure, provides a wider control range of the DC component including positive and negative regions, and has a lower power loss than previous power supply circuits.