By Adjusting Pulse Width Of Light Beam Patents (Class 347/252)
  • Patent number: 10674037
    Abstract: The image processing apparatus of the present invention includes: a first memory configured to store a first threshold value matrix used for halftone processing; a second memory configured to store a second threshold value matrix that is a threshold value matrix used for halftone processing and whose size is larger than the first threshold value matrix; and at least one circuit, the at least one circuit causing processing below: performing halftone processing for image data by using the first threshold value matrix or the second threshold value matrix selected based on attribute information on the image data, and the first threshold value matrix includes threshold values whose maximum number of bits is N and the second threshold value matrix includes threshold values whose maximum number of bits is M (M<N).
    Type: Grant
    Filed: June 12, 2018
    Date of Patent: June 2, 2020
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kenichirou Haruta
  • Patent number: 10326909
    Abstract: A method for selecting a colorant amount for printing is described in which a maximum optical density of an image is identified. The maximum optical density is compared to with a threshold optical density, and when the threshold is exceeded, dot cluster sizes from a first lookup table are selected, otherwise, dot cluster sizes from a second lookup table are selected. A colorant thickness corresponding to the selected dot cluster sizes is selected for printing the image.
    Type: Grant
    Filed: April 10, 2015
    Date of Patent: June 18, 2019
    Assignee: HP Indigo B.V.
    Inventors: Doron Schlumm, Nir Mosenson, Yohanan Sivan, Ziv Berkovich
  • Patent number: 9981495
    Abstract: A printer includes a discharge unit, a first printing unit disposed along a sheet conveying path extending from the discharge unit and configured to print an image on a first sheet while the first sheet is conveyed from the discharge unit to the first printing unit and then to the discharge unit, a second printing unit disposed farther from the discharge unit than the first printing unit along the sheet conveyance path and configured to print an image on a second sheet while the second sheet is conveyed towards the discharge unit therethrough, a scanning unit disposed along the sheet conveying path between the discharge unit and the first printing unit, and configured to scan a surface of the first sheet, and a control unit configured to perform a shading correction of the scanning unit using the second sheet as a white reference.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: May 29, 2018
    Assignee: Toshiba TEC Kabushiki Kaisha
    Inventor: Kengo Saga
  • Patent number: 9606471
    Abstract: An image forming apparatus for forming an image by scanning an image bearer with light modulated in accordance with image information includes a light source configured to emit the light and a control device configured to control the light source in accordance with the image information. The control device sets light emission duration of the light source for forming a particular pixel in the image to be shorter than light emission duration of the light source for forming a normal pixel, which is a pixel other than the particular pixel irk the image, and sets light emission intensity of the light source for forming the particular pixel to be higher than light emission intensity of the light source for forming the normal pixel.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: March 28, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Masaaki Ishida, Atsufumi Omori, Muneaki Iwata, Hayato Fujita
  • Patent number: 9521295
    Abstract: An image forming apparatus includes: a light source; and a light source control unit that supplies a pulse drive current according to image data to the light source. An amplitude of a part of the drive current corresponding to a specified pixel of the image data is larger than an amplitude of a part of the drive current corresponding to a normal pixel of the image data that is a pixel other than the specified pixel and the pulse width of the part of the drive current corresponding to the specified pixel is smaller than the pulse width of the part of the drive current corresponding to the normal pixel.
    Type: Grant
    Filed: December 1, 2014
    Date of Patent: December 13, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hayato Fujita, Masaaki Ishida, Atsufumi Omori, Naoto Watanabe, Muneaki Iwata
  • Patent number: 9406255
    Abstract: Disclosed herein is a lighting period setting method for a display panel which permits control of the peak luminance level by controlling the total lighting period length which is the sum of all lighting periods per field period, the lighting period setting method including the steps of, calculating the average luminance level across the screen based on input image data, determining light emission mode based on the calculated average luminance level, and setting the number, arrangement and lengths of lighting periods per field period according to the setting conditions defined for the determined light emission mode so as to provide the peak luminance level which is set according to the input image data.
    Type: Grant
    Filed: January 14, 2013
    Date of Patent: August 2, 2016
    Assignee: JOLED Inc.
    Inventors: Teppei Isobe, Hiroshi Hasegawa, Hironobu Abe
  • Patent number: 9361857
    Abstract: Disclosed herein is a light emitting period setting method for a display panel wherein the peak luminance level is varied through control of a total light emitting period length which is the sum total of period lengths of light emitting periods arranged in a one-field period, including a step of setting period lengths of N light emitting periods, which are arranged in a one-field period, in response to the total light emitting period length such that the period lengths of the light emitting periods continue to keep a fixed ratio thereamong, N being equal to or higher than 3.
    Type: Grant
    Filed: June 26, 2014
    Date of Patent: June 7, 2016
    Assignee: SONY CORPORATION
    Inventors: Hiroshi Hasegawa, Teppei Isobe, Hironobu Abe
  • Patent number: 9143251
    Abstract: For phase synchronizing nodes, on a node by node basis, following a tree-structured phase distribution network using the infrastructure of a telecommunications network, a first node transfers to a second node phase information substantially in phase with a phase reference internal to the first node and position signaling of the phase information with respect to component elements, such as bits, of a data signal carried by a link linking the nodes. The position signaling can be the number of component elements separating it from the phase information in a packet. The time to transfer the phase information through the link is precisely compensated.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: September 22, 2015
    Assignee: Orange
    Inventors: Sebastien Jobert, Fabrice Deletre, Yves Morlon
  • Patent number: 9104132
    Abstract: An image forming apparatus includes a signal generating unit that stores information on a plurality of dither matrices preset in correspondence with the density level of toner to be attached to the photosensitive member and converts input image data based on the dither matrices to generate a driving signal. The signal generating unit stores information on a first dither matrix corresponding to a first density level and a second dither matrix corresponding to a second density level higher than the first density level. The first dither matrix includes a minute exposure area in which the exposure device is caused to emit light to attain a potential at which no toner adheres to the photosensitive member, and the second dither matrix includes a normal exposure area in which the exposure device is caused to emit light to attain a potential at which toner adheres to the photosensitive member.
    Type: Grant
    Filed: October 23, 2014
    Date of Patent: August 11, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenichi Iida, Yusuke Shimizu, Toshihiko Takayama, Ryo Morihara
  • Publication number: 20150145943
    Abstract: Disclosed are methods and systems for compensating for process direction banding associated with a document processing system including a ROS. According to one exemplary embodiment, a ROS driver uses a plurality of beam delay/advance values to compensate for banding caused by an interaction of a halftone pattern and process direction density variations associated with the ROS.
    Type: Application
    Filed: November 27, 2013
    Publication date: May 28, 2015
    Applicant: Xerox Corporation
    Inventor: Robert Paul Herloski
  • Patent number: 8963980
    Abstract: An image forming apparatus includes an image information retrieval unit that retrieves image information of an image to be formed on a recording material, a density information retrieval unit that retrieves information relating to an image density of the image to be formed in accordance with the image information through analysis of the image information retrieved by the image information retrieval unit, an exposure unit that exposes a rotating image carrier to light in response to the image information retrieved by the image information retrieval unit, and a setting unit that sets, in accordance with the information relating to the image density retrieved by the density information retrieval unit, an exposure period according to which the exposure unit exposes the rotating image carrier to light.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: February 24, 2015
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Takakazu Kobayashi
  • Patent number: 8947734
    Abstract: A pulse width modulation technique is disclosed for use in an image forming device such as a laser printer or a photocopier. The technique implements a pacer to synthesize the frequency of a serializer circuit by stretching (or shrinking) pixel pulse train data. The pacer stretches the pixel pulse train data in accord with increment data that is based upon information about the image forming device, such as the number of bits in the pixel pulse train data, the number of bits in print engine pulse train, the target print engine frequency, and the serializer frequency. The technique can be implemented with digital circuits that provide digital test data.
    Type: Grant
    Filed: July 25, 2007
    Date of Patent: February 3, 2015
    Assignee: Marvell International Ltd.
    Inventors: John D. Marshall, Douglas G. Keithley, Richard D. Taylor
  • Patent number: 8902267
    Abstract: Drawing control methods, laser irradiating apparatuses, drawing control programs, and recording mediums having recorded therewith are provided that make it possible to efficiently carry out drawing with high quality. The drawing control method controls, by a computer, a drawing device which draws what is to be drawn onto multiple unit regions on a surface of a medium. The computer executes a drawing order determining step which determines a drawing order of a line segment included in the what is to be drawn such that multiple continuing line segments over mutually neighboring multiple unit regions are drawn continuously.
    Type: Grant
    Filed: October 14, 2010
    Date of Patent: December 2, 2014
    Assignee: Ricoh Company, Ltd.
    Inventor: Miyuki Oda
  • Patent number: 8890917
    Abstract: In order to improve read stability, a printing condition is set based on not visual read of a user, but read with an optical information reading apparatus. A printing quality evaluation apparatus includes: an image acquiring section that acquires an image; a symbol extracting section that extracts the symbol in which the printing quality can be evaluated from the captured images acquired by the image acquiring section; a printing quality evaluation section that evaluates the printing quality of the symbol extracted by the symbol extracting section; an identification information recognition section that recognizes the identification information identifying each printing condition of the symbol; and an evaluation output section that outputs the identification information, which is recognized by the identification information recognition section, and an evaluation result of the printing quality of the printing quality evaluation section according to the symbol extracted by the symbol extracting section.
    Type: Grant
    Filed: January 12, 2012
    Date of Patent: November 18, 2014
    Assignee: Keyence Corporation
    Inventors: Hajime Matsuda, Takaaki Ito
  • Patent number: 8736896
    Abstract: An optical scanning unit includes a light source including a plurality of light-emitting elements; a light detector to detect a light beam emitted from the light source; a light-flux splitter, angled to the optical axis of the light beam emitted from the light source, having an aperture, a portion of reduced thickness susceptible to warping, a concave face of the warped light-flux splitter as a reflecting face, and a convex face of the warped light-flux splitter opposite the concave face as a non-reflecting face; and a light-flux splitter pressing unit to press the light-flux splitter onto a light-flux splitter holding member without blocking the aperture. Light beam passed the aperture is used as a write-use light flux. The reflecting face reflects a light flux other than the write-use light flux as a monitor-use light flux. The light-flux splitter pressing unit presses a portion of maximum convexity of the non-reflecting face.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: May 27, 2014
    Assignee: Ricoh Company, Ltd.
    Inventor: Susumu Mikajiri
  • Patent number: 8724163
    Abstract: An optical scanning apparatus includes a light source, rotational polygonal mirror, correction data calculating unit, modification computing unit, and adjustment unit. The adjustment unit adjusts drive current supplied to the light source using the correction data calculated by the correction data calculating unit when a first of a plurality of modes is selected or using the correction data calculated by the modification computing unit when a second of the plurality of modes is selected.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: May 13, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuichi Seki
  • Patent number: 8619110
    Abstract: An image forming apparatus including: a photosensitive member; an exposure device configured to form plural solid patch latent images on the photosensitive member; a potential detecting device configured to detect a surface potential of the photosensitive member; a density detecting device configured to detect density of plural solid patch toner images developed by a developing device; and a control device configured to calculate a relation between an exposure amount of a solid image area and a theoretical value of the exposure amount and a ratio of an exposure amount of a line image area to that of the solid image area, based on detection results of the potential detecting device and the density detecting device, calculate, based on the ratio, a relation of the exposure amount of the line image area to the theoretical value, and modulate light output from the exposure device according to the relation.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: December 31, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshiyuki Yamada
  • Patent number: 8519633
    Abstract: A pulsed electric operating current that rises during a pulse duration is generated for operating at least one radiation-emitting semiconductor component. For this purpose, in a method for producing a control device for operating the at least one radiation-emitting semiconductor component, a temporal profile of a thermal impedance representative of the at least one radiation-emitting semiconductor component is determined. A profile of the electric operating current that is to be set is determined depending on the determined temporal profile of the thermal impedance. The control device is furthermore designed such that the profile of the operating current that is to be set is set in each case during the pulse duration.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: August 27, 2013
    Assignee: OSRAM Opto Semiconductor GmbH
    Inventors: Thomas Zahner, Florian Dams, Peter Holzer, Stefan Groetsch
  • Patent number: 8471882
    Abstract: An image forming apparatus, which forms an image by forming an electrostatic latent image on a photosensitive member with a laser beam, developing the electrostatic latent image with a developer to obtain a developer image, and transferring the developer image to a sheet, includes a light source which outputs the laser beam for exposing the photosensitive member; a PLL circuit which generates a multiplied clock that is obtained by multiplying a reference clock; a pulse-width modulating circuit which outputs a pulse-width-modulated signal based on image data and the multiplied clock in order to drive the light source; and a CPU which obtains image data to be input to the pulse-width modulating circuit and, when it is unnecessary to output the pulse-width-modulated signal based on the obtained image data, controls the PLL circuit so as not to generate the multiplied clock.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: June 25, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuzuru Yano
  • Patent number: 8467101
    Abstract: An image forming device includes a density detector that detects image density, and a memory that stores information relating image density to dot size. When a dot size is specified, the image forming device automatically obtains the corresponding image density from the information in the memory, prints a test pattern, compares its density with the density corresponding to the specified dot size, and adjusts an image forming parameter until the density corresponding to the specified dot size is obtained. Dot size can be accurately adjusted in this way without the need for elaborate measuring equipment. In particular, the size of dots used to embed invisible information in images can be accurately controlled.
    Type: Grant
    Filed: September 25, 2008
    Date of Patent: June 18, 2013
    Assignee: Oki Data Corporation
    Inventor: Yasuhisa Sugiyama
  • Patent number: 8446601
    Abstract: A disclosed control device includes a first unit configured to generate image data of multiple images to be superposed one on the other to form a single image and transmit the image data. The second control unit transmits to the first control unit a horizontal sync reference signal for achieving synchronization of the images in a horizontal direction. Based on the horizontal sync reference signal, the first control unit transmits to the second control unit a transfer clock signal that indicates transmission timing of the image data and an effective area signal that indicates an effective area of the image data. The first control unit asserts the effective area signal for an effective-area-signal assertion period that occurs between two consecutive reference-signal assertion periods during which the horizontal sync reference signal is asserted.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: May 21, 2013
    Assignee: Ricoh Company, Ltd.
    Inventor: Eiji Tsuchida
  • Patent number: 8350884
    Abstract: An image forming method including: inputting a pulse width modulated signal into a laser beam output section and thereby outputting a laser beam, wherein a pulse width of the pulse width modulated signal is changed based on image data containing density information; scanning the laser beam onto a surface of a photoreceptor through an optical scanning apparatus and thereby outputting an image; detecting a diameter of the laser beam in a sub-scanning direction formed on the surface of the photoreceptor, the diameter of the laser beam inherent to each optical scanning apparatus and changing along an image height in a main scanning direction; and correcting the pulse width in response to the diameter in the sub-scanning direction so that the image output density is uniform with respect to one and the same input density in the image data.
    Type: Grant
    Filed: October 20, 2009
    Date of Patent: January 8, 2013
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Shinjiro Ito, Kazunori Ishige, Toru Makino
  • Patent number: 8248631
    Abstract: An image forming apparatus includes: an image forming unit for forming a plurality of images on sheets; a receiving unit for receiving job information including identification information for identifying types of the plurality of images and determination information for determining timing of forming the plurality of images on the sheets, from an external instrument; and a control unit for identifying the types of the plurality of images based on the identification information received by the receiving unit, determining the timing of forming the plurality of images on the sheets based on the determination information received by the receiving unit, and allowing the image forming unit to form the plurality of images based on the identified types of the images and on the determined timing.
    Type: Grant
    Filed: May 22, 2009
    Date of Patent: August 21, 2012
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventor: Shouichi Nakamura
  • Patent number: 8233022
    Abstract: It is determined whether a low density area in which pixels having density less than a predetermined density exist in succession is included in an image signal or not, and if the low density area exists, an image is formed by irradiating the laser light in a first condition for a pixel to be interested in each pixel area within the low density area and irradiating the laser light in a second condition being different from the first condition for other pixels in the pixel area. In this way, it is possible to improve reproducibility of a highlight area in a high resolution image and improve reproducibility of characters and line images or the like.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: July 31, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takeo Yamamoto
  • Patent number: 8199182
    Abstract: An exposing device which radiates light on a photoconductor drum which rotates, thereby executing exposure, includes a light-emitting element unit including light-emitting element having an emission area which emits light that is generated, the emission area having a rectangular shape with a long side along a direction perpendicular to a rotational direction of the photoconductor drum, and a short side along the rotational direction, a lens unit which focuses the light, which is emitted from the emission area, on a peripheral surface of the photoconductor drum, thereby executing exposure, and forming on the peripheral surface a beam spot, and a driving circuit which causes the light-emitting element to emit light, thereby making a width of the shape of the beam spot in a direction along the rotational direction close to a width of the beam spot in a direction perpendicular to the rotational direction.
    Type: Grant
    Filed: January 25, 2011
    Date of Patent: June 12, 2012
    Assignee: Casio Computer Co., Ltd.
    Inventors: Yoshiyuki Matsuoka, Isao Ebisawa, Kenji Kobayashi
  • Patent number: 8179433
    Abstract: The microscopic imaging apparatus includes a system controlling unit for obtaining a VD time setting value, and for obtaining the number of electric charge subtracting pulses, a synchronization signal generating unit for generating a vertical synchronization signal on the basis of the VD time setting value output from the system controlling unit and the horizontal synchronization signal, and a timing generating unit for extracting the electric charge of the imaging device by supplying the horizontal synchronization signal by the number of electric charge subtracting pulses to the imaging device as the electric charge subtracting pulses, and for generating a read pulse synchronous with the vertical synchronization signal in order to stop the accumulation of the electric charge of the imaging device after exposure is started.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: May 15, 2012
    Assignee: Olympus Corporation
    Inventor: Hiroshi Fujiki
  • Patent number: 8058633
    Abstract: A pulse width modulation signal generating device which generates a pulse width modulation signal for modulating laser beam according to image data includes: a cycle signal output circuit which outputs a cycle signal having a cycle corresponding to a drawing rate for drawing the image data by the laser beam; and a pulse width modulation circuit which receives supply of the image data and the cycle signal and modulates a pulse wave having a cycle determined by the cycle signal by changing duty ratio of the pulse wave based on the image data to produce the pulse width modulation signal.
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: November 15, 2011
    Assignee: Seiko Epson Corporation
    Inventor: Tomio Ikegami
  • Patent number: 7898562
    Abstract: An exposing device which radiates light on a photoconductor drum which rotates, thereby executing exposure, includes a light-emitting element unit including light-emitting element having an emission area which emits light that is generated, the emission area having a rectangular shape with a long side along a direction perpendicular to a rotational direction of the photoconductor drum, and a short side along the rotational direction, a lens unit which focuses the light, which is emitted from the emission area, on a peripheral surface of the photoconductor drum, thereby executing exposure, and forming on the peripheral surface a beam spot, and a driving circuit which causes the light-emitting element to emit light, thereby making a width of the shape of the beam spot in a direction along the rotational direction close to a width of the beam spot in a direction perpendicular to the rotational direction.
    Type: Grant
    Filed: September 4, 2008
    Date of Patent: March 1, 2011
    Assignee: Casio Computer Co., Ltd.
    Inventors: Yoshiyuki Matsuoka, Isao Ebisawa, Kenji Kobayashi
  • Patent number: 7872663
    Abstract: A light emitting device includes a plurality of light emitting elements, a first storage unit that stores first correction values corresponding to the light emitting elements, a counting unit that counts the number of pixels whose gray-scale values designated by image data are within a predetermined range included in an image, a selection unit that selects a first mode or a second mode according to the relationship between the number counted by the counting unit and a threshold value, and a driving unit that drives the light emitting elements corresponding to the predetermined number of pixels to emit amounts of light corresponding to the first correction values when the first mode is selected by the selection unit, and drives the light emitting elements corresponding to the predetermined number of pixels to emit amounts of light corresponding to the image data when the second mode is selected by the selection unit.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: January 18, 2011
    Assignee: Seiko Epson Corporation
    Inventor: Taketo Chino
  • Patent number: 7852510
    Abstract: Data-processing systems and methods include a rendering device which renders documents based upon the timing and duration of a laser beam associated with particular pixel data. Additionally, a controlling mechanism for controlling and adjusting the particular pixel data can be provided, wherein the controlling mechanism is subject to pixel clock signal in order to optimize a performance of the rendering device under varying rendering parameters and thereby enhance the quality of data rendered via the rendering device. Such a controlling mechanism can be implemented as a programmable phase locked loop circuit to which a pixel clock signal and a frequency are applied in order to provide at least one output signal for controlling the laser beam.
    Type: Grant
    Filed: April 28, 2005
    Date of Patent: December 14, 2010
    Assignee: Xerox Corporation
    Inventors: Mostafa R. Yazdy, Mehrdad Zomorrodi
  • Patent number: 7812979
    Abstract: There is provided an information processing apparatus previewing on a display screen ink-character information and braille information which are printed and embossed on the same process sheet, the apparatus including: an ink-character previewing device for previewing the ink-character information; a braille previewing device for previewing the braille information; and a preview switching device controlling the ink-character previewing device and the braille previewing device and capable of selectively switching a display mode among a display of only the ink-character information, that of only the braille information, and that of the ink-character information and the braille information when printing and embossing operations are performed in a manner in which the ink-character information and the braille information are at least partially overlapped with each other on the process sheet.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: October 12, 2010
    Assignees: Seiko Epson Corporation, King Jim Co., Ltd.
    Inventors: Makoto Takada, Seiji Tanaka, Takayuki Uehara
  • Patent number: 7791635
    Abstract: In a disclosed image forming apparatus, a developing bias applied to a developer carrier or exposure energy with which an image carrier is exposed is adjusted such that an isolated one-dot image on the image carrier has a predetermined image density. When the image carrier is exposed to form dot images continuously arranged in a sub scanning direction, the exposure time period for each dot image is shorter than a time period for exposing the image carrier to form the isolated one-dot image.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: September 7, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiko Ogawa, Akihiro Kawasaki
  • Publication number: 20100103240
    Abstract: An image data is pre-processed in parallel by a pre-processing unit (A) and a pre-processing unit (B) arranged in parallel. The image data is transferred in synchronization with an image processing signal obtained by ORing a BD signal and an interpolation signal. Laser scanning for plural beams of a multi-laser beam is performed in synchronization with the BD signal. Color matching processing or zeronization processing for the multi-laser beam is performed in synchronization with the image processing signal.
    Type: Application
    Filed: October 28, 2009
    Publication date: April 29, 2010
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Syunichi ONO, Takashi OKANO
  • Patent number: 7672345
    Abstract: A drive signal for driving a semiconductor laser is generated on the basis of an image signal inputted in synchronism with a pixel clock. A bias signal to the semiconductor laser is generated at a timing earlier than the drive signal by a predetermined time. The bias signal is disabled in synchronism with the leading edge of the drive signal.
    Type: Grant
    Filed: January 20, 2009
    Date of Patent: March 2, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tsuyoshi Moriyama
  • Patent number: 7586507
    Abstract: A method for forming a pixel (20) having a predetermined density onto a sensitized recording medium moving in a length direction energizes a pixel exposure source (14) to begin exposure at the leading edge (34) of a pixel (20) and for a first predetermined time interval. The pixel exposure source (14) is de-energized for a period depending on the predetermined density and on media transport speed, then re-energized at the termination of the period. The pixel exposure source (14) is then de-energized at the end of a second predetermined time interval to terminate exposure at the trailing edge (36) of the pixel (20), whereby spatial dimensions of each pixel (20) are maintained at variable transport speed or density of pixel (20).
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: September 8, 2009
    Assignee: Eastman Kodak Company
    Inventors: Scott P. MacKenzie, Nelson A. Blish
  • Patent number: 7580053
    Abstract: An image data processing section subjects input image data to image processing, and outputs first to fourth image data. First to fourth pulse width modulation circuits are PWM circuits in each of which a plurality of reference positions are set in one pixel, and output pulses corresponding to the first to fourth image data. A synthesis circuit synthesizes the pulses output from the first to fourth pulse width modulation circuits, and a laser emits a light beam in accordance with the synthesized pulse.
    Type: Grant
    Filed: April 4, 2008
    Date of Patent: August 25, 2009
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Daisuke Ishikawa, Koji Tanimoto, Kenichi Komiya, Yuji Inagawa
  • Patent number: 7450144
    Abstract: A photo-printing system includes a laser exposure unit, a reference clock generation unit, an image input unit, and a controller. The image input unit receives first pixel data and second pixel data to be expressed after the first pixel in accordance with image data. In a first control, the first and second pixels are scanned for exposure in a laser emission region state wherein each of the scan-start timings of the first and second pixels are controlled in accordance with a reference clock. In a second control, the first pixel is scanned for exposure in a nonlinear light emission region state, and the second pixel having a density equal to or lower than a predetermined density is scanned for exposure in the laser emission region state, the scan-start timing of the second pixel is advanced with respect to the first control.
    Type: Grant
    Filed: March 22, 2006
    Date of Patent: November 11, 2008
    Assignee: Noritsu Koki Co., Ltd.
    Inventors: Yozo Ohki, Kazuhiro Yoshida
  • Patent number: 7417660
    Abstract: An image forming apparatus generates a PWM signal corresponding to input image data and controls a timing of a light source to emit a light beam based on the PWM signal in order to perform tone reproduction. The image forming apparatus includes a data processing unit configured to generate the PWM signal for one pixel based on image data for continuous two pixels in the image data. The data processing unit selects an origin of pulse growth in generation of the PWM signal for one pixel in accordance with the image data for the two pixels to generate the PWM signal.
    Type: Grant
    Filed: August 17, 2005
    Date of Patent: August 26, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hajime Motoyama, Hajime Kaji, Naoto Yamada, Yoshitaka Yamazaki, Junichi Noguchi, Takayuki Kawakami, Satoshi Ogawara, Yushi Oka, Akihito Mori
  • Publication number: 20080186376
    Abstract: An image data processing section subjects input image data to image processing, and outputs first to fourth image data. First to fourth pulse width modulation circuits are PWM circuits in each of which a plurality of reference positions are set in one pixel, and output pulses corresponding to the first to fourth image data. A synthesis circuit synthesizes the pulses output from the first to fourth pulse width modulation circuits, and a laser emits a light beam in accordance with the synthesized pulse.
    Type: Application
    Filed: April 4, 2008
    Publication date: August 7, 2008
    Inventors: Daisuke Ishikawa, Koji Tanimoto, Kenichi Komiya, Yuji Inagawa
  • Publication number: 20080180514
    Abstract: An image forming apparatus applies a shading correction to an image read from a white reference board 18, and determines presence or absence of stripe-like noise in the image read therefrom after applying the shading correction. The apparatus exposes an area at which there is no noise in the white reference board 18 to create a white reference value for a shading correction for reading a document after that time.
    Type: Application
    Filed: January 31, 2007
    Publication date: July 31, 2008
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hidekazu Sekizawa, Naoyuki Misaka, Jun Sakakibara
  • Patent number: 7388694
    Abstract: Laser information is prepared which indicates the irradiation interval and intensity level to be irradiated on an optical disc in advance. Then, when image drawing is indicated together with the indication of the forming spacing for pits, a laser is controlled so as to achieve the irradiation interval and intensity level indicated by the laser information that corresponds to the indicated formation spacing to fabricate pits in the optical disc.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: June 17, 2008
    Assignee: Yamaha Corporation
    Inventor: Morito Morishima
  • Patent number: 7369151
    Abstract: An image data processing section subjects input image data to image processing, and outputs first to fourth image data. First to fourth pulse width modulation circuits are PWM circuits in each of which a plurality of reference positions are set in one pixel, and output pulses corresponding to the first to fourth image data. A synthesis circuit synthesizes the pulses output from the first to fourth pulse width modulation circuits, and a laser emits a light beam in accordance with the synthesized pulse.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: May 6, 2008
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Daisuke Ishikawa, Koji Tanimoto, Kenichi Komiya, Yuji Inagawa
  • Patent number: 7327380
    Abstract: The invention relates to an apparatus for printing a multibit per pixel image (10) from a halftone binary digital bitmap having pixels having a multibit per pixel image memory for receiving the multibit per pixel image; a lookup table (16) external to the memory disposed in a programmable gate array (18) for converting the multibit per pixel image to a base duty cycle (20) wherein the base duty cycle is disposed in the programmable gate array and is adapted for creating a modulated drive signal (22) from the base duty cycle to modulate an exposure (24) for each pixel in the multibit per pixel image; and a printer (28) adapted for using the modulated exposure to print an image, having a dpi greater than 1400, further comprising a drum (32) capable of spinning, and an encoder (34) disposed on the drum for providing a home signal (36) and a pixel rate (38).
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: February 5, 2008
    Assignee: Eastman Kodak Company
    Inventors: Kurt M. Sanger, Thomas A. Mackin, Seung Ho Baek
  • Patent number: 7292260
    Abstract: An image forming apparatus records an image on a photosensitive material by controlling a light emission amount from a plurality of light emission elements that each emit light in accordance with a supplied light emission control signal. The apparatus has a control signal generation unit and a first and second signal generation sections and a signal switching section. The control signal generation unit generates a first light amount control signal from a density modulation. The second signal generation section generates an ON/OFF control signal and a second light amount control signal as a pair of signals from a combination of a density modulation and an area modulation. The signal switching section generates a light emission control signal by performing signal switching between the first light amount control signal and the pair of the signals. The exposure by the light emission is overlaid.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: November 6, 2007
    Assignee: FUJIFILM Corporation
    Inventors: Hideyasu Ishibashi, Hiroaki Hyuga
  • Patent number: 7271821
    Abstract: A laser scanning assembly generates a laser beam and scans the laser beam through a plurality of scan lines to form desired dots. Each scan line is positioned to overlap an adjacent scan line and each dot includes a plurality of segments. The scanning assembly scans the laser beam through multiple scan lines to fully discharge each segment of each dot. The laser scanner assembly would typically be part of a laser printer.
    Type: Grant
    Filed: December 16, 2004
    Date of Patent: September 18, 2007
    Assignee: Marvell International Technology Ltd.
    Inventor: Douglas Gene Keithley
  • Patent number: 7269193
    Abstract: A semiconductor laser driving circuit for driving a semiconductor laser as an exposure light source is used in an image recording apparatus for recording an image using a light beam from the laser. The light beam emitted from the laser is subjected to pulse modulation in correspondence with a command signal. The circuit includes an error amplifier for amplifying a difference between the command signal and a signal fed back from the laser to output an output signal, a diode and a resistor connected in series between an input terminal and an output terminal of the error amplifier and a driver for driving the laser based on the output signal.
    Type: Grant
    Filed: June 28, 2005
    Date of Patent: September 11, 2007
    Assignee: Fuji Film Corp.
    Inventors: Yoshinori Morimoto, Tsuyoshi Tanabe, Kenichi Saito, Yoichi Suzuki, Tadashi Masuda, Kiyoshi Kondou
  • Publication number: 20070188592
    Abstract: A method for controlling an optical scanning apparatus, includes generating an exposing signal from a pattern data for an optical scanning apparatus, which includes a light source that emits a light beam, a deflector that deflects the light beam emitted from the light source by means of a deflection mirror surface oscillating sinusoidally, and a scanning optical system that has an arcsine characteristics and that images the light beam deflected by the deflector on a surface-to-be-scanned in a spot, and which makes the imaged spot scan the surface-to-be-scanned in the main scanning direction while modulating the light beam emitted from the light source based upon the pattern data indicating a position on the surface-to-be-scanned the light beam exposes so that the light beam exposes a predetermined position on the surface-to-be-scanned, the exposing signal being a train of pulses arranged on a time axis in accordance with an arrangement in the main scanning direction of values, which the pattern data have, ind
    Type: Application
    Filed: February 2, 2007
    Publication date: August 16, 2007
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hiroshi TOYAMA, Yujiro NOMURA, Ken IKUMA
  • Patent number: 7253924
    Abstract: A method for printing multiple binary bitmaps (10) with an original density level (12a) and a color (18), wherein the color (18) is the same for all the multiple binary bitmaps (10), by combining “n” number of binary bitmaps into “p” bits of a multibit image forming a “p” bit image (20), identifying at least one overprint (24a), predicting an overprint density (26a) for each overprint, calculating a set of exposures (28) needed to image each overprint density (24a) and original density (12a), setting a maximum exposure level (30) that is a number greater than or equal to the maximum of the set of exposures (28), calculating pulse width modulation levels (30) for the set of exposures (28) using the set maximum exposure level (30), and printing the color (28) at the set maximum exposure level (30) using the pulse width modulation levels (30) for each level of the “p” bit image (20) in a single pass.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: August 7, 2007
    Assignee: Eastman Kodak Company
    Inventors: Kurt M. Sanger, Seung Ho Baek, Thomas A. Mackin
  • Patent number: 7253829
    Abstract: A print apparatus including a photoconductive drum, a laser scanning unit (LSU) to scan a surface of the photoconductive drum, and an image processing unit to generate and output dot size information corresponding to externally input image data. The dot size information determines sizes of individual dots on an image to be printed, a memory unit to store dot size compensation values related to a scanning distance of laser beams emitted from the LSU to the surface of the photoconductive drum to the LSU. The compensation values change the dot size information. The apparatus further includes a light intensity difference compensation unit to compensate for the dot size information according to the stored compensation values if the dot size information is received, and a pulse width modulation (PWM) unit to generate and output a pulse signal to control the scanning of the laser beams of the LSU according to the compensated dot size information.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: August 7, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Goo-soo Gahang, Jung-tag Gong, Sang-yun Shin
  • Patent number: RE40945
    Abstract: A method of increasing the scanning resolution of a scanner through controlling its driving system. By suitably adjusting the timing relationship between motor pulses and exposure pulses, a low-resolution driving system can produce a high-resolution image with no additional production cost incurred.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: October 27, 2009
    Inventors: Chuan-Yu Hsu, Chen-Hsiang Shih