Scan Synchronization (e.g., Start-of-scan, End-of-scan) Patents (Class 347/235)
  • Patent number: 10481518
    Abstract: An image forming apparatus including: a drive motor configured to rotate a rotary polygon mirror to deflect light beam; a signal generation unit configured to generate a rotation synchronous signal; and a rotation control unit configured to control a rotation speed of the rotary polygon mirror, wherein the rotation control unit executes a masking processing of masking control of the drive motor based on the rotation synchronous signal, wherein a time period of a first masking processing for a first rotation speed is shorter than a time period of a second masking processing for the second rotation speed, and wherein when the rotation speed of the rotary polygon mirror is changed from the first rotation speed to the second rotation speed, the rotation control unit switches the masking processing from the first masking processing to the second masking processing after reduction of the rotation speed of the rotary polygon mirror is started.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: November 19, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takahiro Kamikura, Satoru Takezawa
  • Patent number: 10401755
    Abstract: The scanning apparatus includes a control unit that controls an emission state of a light source to perform switching between first and a second emission states, wherein as a signal according to a light amount, an output unit outputs a first value when light received by the output unit has a first light amount and outputs a second value when the light received by the output unit has a second light amount larger than the first light amount, and the control unit performs switching from the first emission state to the second emission state when an output time period of a signal of the second value corresponding to the second light amount is equal to or more than a predetermined time period.
    Type: Grant
    Filed: November 5, 2018
    Date of Patent: September 3, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventor: Shunsuke Tanaka
  • Patent number: 10138549
    Abstract: A scanning optical apparatus includes: a deflection unit configured to deflect a light flux from a light source in a main scanning direction; an incident optical system configured to introduce the light flux from the light source to the deflection unit; a condensing optical system configured to condense the light flux from the deflection unit onto a scanned surface; and a reflection member arranged in a light path of the light flux deflected in the main scanning direction by the deflection unit and configured to reflect a part of the deflected light flux. The reflection member has a reflection surface configured to reflect the deflected light flux, a first end surface formed in the main scanning direction, and a second end surface formed in a sub-scanning direction perpendicular to the main scanning direction, and the second end surface has a higher degree of corrosion resistance than the first end surface.
    Type: Grant
    Filed: May 27, 2015
    Date of Patent: November 27, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventor: Kazumi Kimura
  • Patent number: 9983502
    Abstract: A setting unit of a controller mounted on a control board sets a first mode for generating, from image data, PWM data indicating a pattern for causing an LD to emit light and transmitting to a laser driving board, or a second mode for transmitting to the laser driving board image data prior to generation of the PWM data. A data conversion unit, in the first mode, converts inputted image data into N pieces of PWM data respectively corresponding to N LDs, and in the second mode, converts inputted image data into image data for each scanning line. A P/S conversion unit converts data outputted from the data conversion unit from a serial format into a parallel format, and transmits the converted data to the laser driving board as control data.
    Type: Grant
    Filed: November 10, 2016
    Date of Patent: May 29, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shoji Takeda, Katsuyuki Yamazaki
  • Patent number: 9778540
    Abstract: The present invention is based on a two-dimensional photonic crystal in which are inserted, in a controlled manner, defects that originate the waveguides and the resonant cavity that integrate the device. Its main function is to provide the control of the passage of an electromagnetic signal over a communications channel, blocking (state off) or allowing (state on) the passage of the signal. It also has the function of changing the propagation direction of an electromagnetic signal by an angle of 60 degrees, offering greater flexibility in the design of integrated optical systems. The operating principle of the device is associated with the excitation of dipole modes in the resonant cavity, which is based on a magneto-optical material.
    Type: Grant
    Filed: May 22, 2015
    Date of Patent: October 3, 2017
    Assignee: UNIVERSIDADE FEDERAL DO PARA—UFPA
    Inventors: Victor Dmitriev, Gianni Masaki Tanaka Portela, Raphael Rafsandjani Batista
  • Patent number: 9535361
    Abstract: An image forming apparatus, including: a polygon mirror; a first optical sensor; a second optical sensor; and a controller configured to (a) determine a second-beam exposure standby time which is a time period from a timing when the first beam deflected by a first surface of the polygon mirror has been detected by the first sensor to a timing when scanning exposure of the second beam deflected by a second surface of the polygon mirror is started, based on a measured time which is a time period from the timing of detection by the first sensor to a timing of detection of the second beam by the second sensor and (b) start the scanning exposure of the second beam deflected by the second surface when the second-beam exposure standby time elapses after the first beam deflected by the first surface has been detected by the first optical sensor.
    Type: Grant
    Filed: March 23, 2016
    Date of Patent: January 3, 2017
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Junichi Yokoi
  • Patent number: 9383675
    Abstract: An image forming section includes a bearing member configured to bear an image, and a light-emitting-element array having a plurality of light emitting elements arranged linearly in an arrangement direction. The image forming section is configured to form an image on the bearing member by using the plurality of light emitting elements to form the image on a sheet. A reader is configured to read an image formed on a sheet. A memory stores instructions, the instructions, when executed by a processor, causing the processor to perform: a pattern reading process of controlling the reader to read a sheet on which a pattern image is formed, the pattern image being an image for detecting positional deviation of the light-emitting-element array; and a deviation calculating process of calculating an amount of positional deviation of the light-emitting-element array based on a reading result by the pattern reading process.
    Type: Grant
    Filed: February 27, 2014
    Date of Patent: July 5, 2016
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Kentaro Murayama
  • Patent number: 9365050
    Abstract: A light-emitting element array module includes a control driver configured to receive print data and operate, and light-emitting element array chips configured to receive a signal from the control driver, respectively, and operate, wherein the light-emitting element array chips are connected to the control driver through respective data lines, and the control driver controls an operation point in time of each of the light-emitting element array chips by adjusting input points in time of a start signal and a data signal according to a registration error of each of the light-emitting element array chips.
    Type: Grant
    Filed: February 20, 2015
    Date of Patent: June 14, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Su-hwan Kim, Wan-chin Kim
  • Patent number: 9354541
    Abstract: According to an image forming apparatus and an exposure position adjusting method of one aspect of the present invention, an exposure section scans a plurality of light beams to form a plurality of electrostatic latent images periodically along a main-scanning direction of the photoreceptor at a predetermined pitch in a sub-scanning direction of the photoreceptor. Next, a surface potential detecting section detects electric potentials of the plurality of electrostatic latent images formed on the surface of the photoreceptor, along the main-scanning direction. Furthermore, a controller calculates exposure timings by the plurality of light beams in the exposure section on the basis of a detection result by the surface potential detecting section.
    Type: Grant
    Filed: March 27, 2015
    Date of Patent: May 31, 2016
    Assignee: KONICA MINOLTA, INC.
    Inventors: Ryo Hasegawa, Katsuyuki Hirata
  • Patent number: 9323171
    Abstract: An optical scanning device including a light source and a rotating polygon mirror having a plurality of reflective surfaces scans a scan area of a surface in a main scanning direction with the light flux emitted from the light source and reflected by the rotating polygon mirror. All the light flux is reflected by a first reflective surface when light flux deflected by the rotating polygon mirror is directed onto a center position of the scan area, and a part of the light flux incident to the rotating polygon mirror is reflected by a second reflective surface adjacent to the first reflective surface when light flux reflected by the rotating polygon mirror is directed onto at least one end of both ends of the scan area and the light flux obliquely enters a plane perpendicular to a rotation axis of the rotating polygon mirror.
    Type: Grant
    Filed: October 1, 2014
    Date of Patent: April 26, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yukio Itami, Yukihisa Yokoyama, Naoki Miyatake
  • Patent number: 9229355
    Abstract: A method for generating a BD signal and identifying a reflection surface after a polygonal mirror has reached approximately constant rotation speed increases time to start image formation because the step of generating the BD signal is needed. An image forming apparatus identifies a reflection surface on which a light beam is incident by using the period of an FG signal.
    Type: Grant
    Filed: August 28, 2014
    Date of Patent: January 5, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuta Nito
  • Patent number: 9170521
    Abstract: In order to detect a passage timing of a light beam and to suppress cost, a light beam detection circuit (2) includes a detection signal generation section (34) configured to receive a light beam for scanning of a scanning target (101A) with one optical sensor (10), and generate a detection signal corresponding to an amount of received light; a reference signal output section (44) configured to output a reference signal that is in proportion to a light-amount control signal of a light-emission element (LD1) that emits the light beam; and a synchronizing signal generation section (35) configured to compare a detection signal generated by the detection signal generation section (34) with a reference signal output from the reference signal output section (44) to generate a synchronizing signal to determine a position to start scanning of the scanning target (101A) with the light beam.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: October 27, 2015
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Kazutaka Matsumoto
  • Patent number: 9139020
    Abstract: Methods and apparatuses that facilitate the alignment of multiple color planes of a latent image in a multi-beam multi-pass printer. The methods include determining, during a first pass of a transfer medium of a multi-beam printer, a first time interval between when at least one light beam from a multi-beam device is detected and when a top of a page is detected at a selected location of the transfer medium, the multi-beam device including a plurality of light beam sources, and the first pass to form a first color plane of a latent image on the transfer medium. The methods further include selecting, based at least in part on the determined first time interval, a first one of the plurality of light beam sources to begin illuminating the transfer medium to create the first color plane on the transfer medium during the first pass of the transfer medium.
    Type: Grant
    Filed: April 24, 2013
    Date of Patent: September 22, 2015
    Assignee: Marvell International Ltd.
    Inventors: Douglas Gene Keithley, Gregory L Unruh
  • Patent number: 9069174
    Abstract: An optical scanning unit includes a rotatable multi-faceted mirror having a plurality of faces reflecting light flux emitted from a light source to scan a scanning area in a main scanning direction. A width of the light flux striking the rotatable multi-faceted mirror is smaller than a length of a face of the rotatable multi-faceted mirror. The entire of light flux striking the rotatable multi-faceted mirror is reflected at a first face when the light flux reflected by the rotatable multi-faceted mirror is directed to the center portion of the scanning area. A part of the light flux striking the rotatable multi-faceted mirror is reflected at the first face while the remaining of the light flux is reflected at a second face when the light flux reflected by the rotatable multi-faceted mirror is directed to a least one of the two end portions of the scanning area.
    Type: Grant
    Filed: July 3, 2013
    Date of Patent: June 30, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yukio Itami, Yoshinori Hayashi, Naoki Miyatake, Yukihisa Yokoyama
  • Patent number: 9024990
    Abstract: A light scanning unit and an image forming apparatus employing the same. The light scanning unit deflects light in a main scanning direction, irradiates the light on a photoconductive drum, and includes a beam detecting sensor to detect a horizontal synchronization signal by receiving a part of the light beam reflected and scanned by a beam deflector, and leads of terminals of the beam detecting sensor are not exposed to the light beam to be scanned.
    Type: Grant
    Filed: March 28, 2012
    Date of Patent: May 5, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-geun Lim, Gu-dal Kwon
  • Patent number: 8994768
    Abstract: In an optical scanning apparatus, a light source includes a plurality of light emitting elements. A light beam output from the source is scanned and deflected by a polygon mirror so as to form an electrostatic latent image on a surface of a light sensitive member. A control unit controls the source so that the source outputs the light beam in a first period before a second period in which the light beam deflected by the mirror forms the image. During the first period for outputting the light beam from the source a period for scanning a non-image region of the member in a state in which the rotation speed of the mirror is being accelerated or decelerated is made longer than a period for scanning the non-image region of the member in a state in which the rotation speed of the mirror is controlled at a constant speed.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: March 31, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventor: Shunsaku Kondo
  • Patent number: 8982171
    Abstract: An image forming apparatus includes a light source which illuminates in response to image data, and a deflector to deflect an optical beam output from the light source into a scanning beam running along a main scanning line across an image forming area in a main scanning direction. There are plurality of beam detectors to detect the scanning beam at a plurality of different positions along the main scanning line, the plurality of beam detectors including first and second beam detectors detecting the scanning beam at positions in front-end and rear-end sides, respectively, in the main scanning direction.
    Type: Grant
    Filed: April 8, 2011
    Date of Patent: March 17, 2015
    Assignee: Ricoh Company, Ltd.
    Inventor: Shukuya Yuuichiroh
  • Patent number: 8976215
    Abstract: An image forming apparatus includes a plurality of photosensitive media, a light source unit which comprises a plurality of light sources, a polygon mirror which deflects a plurality of beams output from the plurality of light sources into the plurality of photosensitive media using a plurality of reflective surfaces, a beam detector which receives beams reflected from the polygon mirror during a rotating process of the polygon mirror, and outputs a beam detection signal, and a horizontal sync signal generator which receives the beam detection signal and counts beam reflecting times during which the beams are reflected from the plurality of reflective surfaces, and compares the plurality of counted beam reflecting times with the compensation values calculated for the reflective surfaces, respectively, generates a horizontal sync signal for a corresponding reflective surface, and provides the horizontal sync signal to the light source unit.
    Type: Grant
    Filed: November 15, 2013
    Date of Patent: March 10, 2015
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Si-joong Jang
  • Patent number: 8913096
    Abstract: An optical scanning device that scans a scanning surface in a main scanning direction. The device includes a surface emitting laser as a light source, an optical deflector that deflects a light flux from the light source while rotating around a rotation axis, a monitor light receiving element, a synchronization detection light receiving element, a monitor optical system that directs the monitor light flux to the monitor light receiving element, a synchronization detection optical system that directs the synchronization detection light flux to the synchronization detection light receiving element, and a scanning optical system that directs a scanning light flux to the scanning surface. A combined focal length of the monitor optical system in the main scanning direction is smaller than a combined focal length of the synchronization detection optical system in the main scanning direction.
    Type: Grant
    Filed: August 19, 2011
    Date of Patent: December 16, 2014
    Assignee: Ricoh Company, Limited
    Inventor: Kohji Sakai
  • Patent number: 8908002
    Abstract: An optical scanning device has a light deflector deflecting a light beam from a light source, a synchronization detection sensor determining timing of starting scanning in main scanning direction based on timing of detecting the light beam scanned in main scanning direction by the light deflector, and a pre-sensor imaging optical system imaging the light beam reflected from the light deflector on the synchronization detection sensor. The pre-sensor imaging optical system moves the imaging position of the light beam on the synchronization detection sensor in a direction making the timing of detecting the light beam earlier or later according to whether variation in temperature causes the magnification of the scanning optical system in main scanning direction to increase or decrease respectively.
    Type: Grant
    Filed: May 21, 2014
    Date of Patent: December 9, 2014
    Assignee: KYOCERA Document Solutions Inc.
    Inventors: Shingo Yoshida, Chika Sawamoto
  • Patent number: 8854406
    Abstract: Disclosed are methods, systems, and/or apparatus for the collective marking of a surface by two or more laser beams generated by a laser controller. A method includes receiving one or more input signals from a controller of the laser system. The method also includes adjusting a first mirror through a first galvanometer scanner, a second minor through a second galvanometer scanner, a third mirror through a third galvanometer scanner, and a fourth mirror through a fourth galvanometer scanner based on the one or more input signals. The method further includes steering, through the first mirror and the second mirror, a first laser beam generated by the controller and transmitted to a marking head through a beam delivery vessel; and steering, through the third mirror and the fourth minor, a second laser beam generated by the controller and transmitted to the marking head through another beam delivery vessel.
    Type: Grant
    Filed: December 5, 2013
    Date of Patent: October 7, 2014
    Assignee: Telesis Technologies, Inc.
    Inventors: Ashot Mesropyan, Michael Watts
  • Patent number: 8837011
    Abstract: There is provided an image forming apparatus comprising: detection means for detecting position information indicating a scanning position; interval prediction means for predicting a first scanning line interval indicating a distance in the sub-scanning direction between the scanning line of interest and a succeeding scanning line to be scanned after the scanning line of interest; interval calculation means for calculating, by using the position information held by the holding means, a second scanning line interval indicating a distance in the sub-scanning direction between the scanning line of interest and the scanned scanning line; and rate calculation means for calculating a correction rate on an exposure amount for the scanning line of interest so that a predicted density calculated using the first scanning line interval and the second scanning line interval matches with a predicted density calculated using a predetermined reference scanning line interval.
    Type: Grant
    Filed: October 27, 2011
    Date of Patent: September 16, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoichi Takikawa, Hideki Kubo, Takashi Ochiai
  • Patent number: 8823761
    Abstract: An optical scanning device includes a light source that emits a laser beam, a deflector that deflects the emitted laser beam, a scanning lens that causes the deflected laser beam to scan a surface of a photosensitive body at a uniform velocity, a reflector having a reflective surface that reflects the deflected laser beam toward the photosensitive body among the laser beams that have passed through the scanning lens, and a synchronization sensor that receives the laser beam from the reflector and outputs a detection signal. The reflector is set so that a scanning speed in a main scanning direction of the laser beam on a light-receiving surface of the synchronization sensor becomes greater than a value obtained by dividing a scanning distance of the laser beam in the main scanning direction on the light-receiving surface of the synchronization sensor by a response delay time of the synchronization sensor.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: September 2, 2014
    Assignee: Kyocera Mita Corporation
    Inventor: Shingo Yoshida
  • Patent number: 8817059
    Abstract: An optical scanning apparatus, including: a deflector including deflection surfaces and configured to deflect, by the deflection surfaces, light beams respectively emitted from light emitting portions for scanning in a main scanning direction; an imaging optical system configured to guide the light beams deflected for scanning by the deflection surfaces to a surface to be scanned; a light source including the light emitting portions arranged so as to be separated from each other in a sub-scanning direction perpendicular to the main scanning direction and an optical axis direction of the imaging optical system; and a controller configured to control the light source in such a manner that a difference between scanning start timings of the light beams at two adjacent deflection surfaces among the deflection surfaces is different from a difference between scanning start timings of the light beams at other two adjacent deflection surfaces among the deflection surfaces.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: August 26, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Genichiro Kudo
  • Patent number: 8767028
    Abstract: An image forming apparatus having: a light source for emitting a beam; a deflector for deflecting the beam; a light receiving element for receiving the beam and generating a detection signal; a converter for converting electric potentials of the detection signal into data values and generating time data associated with the data values; and a first calculator for calculating a position of center of the beam from the data values and the time data.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: July 1, 2014
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Daisuke Fujita, Shinpei Arino
  • Patent number: 8736655
    Abstract: Disclosed are a light scanning unit and an electrophotographic image forming apparatus including the light scanning unit. The light scanning unit may include a light source emitting a light beam, a beam deflector that deflects and scans the light beam emitted from the light source in a main scanning direction, a scanning optical system forming an image of a first portion of the light beam that is deflected and scanned by the beam deflector on a scanning surface and a beam detection sensor receiving a second portion of the light beam that is deflected and scanned by the beam deflector for generating a synchronization signal. The beam detection sensor may include a light receiving surface for receiving the second portion of the light beam, and at least two output terminals that are arranged outside an area of the light receiving surface within which the incident second portion of the light beam is confined.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: May 27, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jong-Min Lee
  • Patent number: 8723906
    Abstract: This image-forming apparatus includes a plurality of photosensitive drums, a plurality of laser scanning units, and a motor control unit. A motor control unit detects the time difference between a change point of the detection signal of a reference color and the change points of colors targeted for phase correction, and, when the absolute value of the time difference is greater than a threshold, carries out a rough adjustment process for reducing the time difference by a drive signal with which a base period has been changed by a first period change amount and thereafter carries out a fine adjustment process for reducing the time difference by a drive signal with which the base period has been changed by a second period change amount smaller than the first period change amount.
    Type: Grant
    Filed: October 20, 2012
    Date of Patent: May 13, 2014
    Assignee: KYOCERA Document Solutions Inc.
    Inventor: Yuichi Ninomiya
  • Patent number: 8723907
    Abstract: Since a photodiode (PD) is disposed in the vicinity of the plurality of light emitting elements and, therefore, the PD also receives a laser beam emitted only by a bias current during the APC period, setting a bias current based on a result of light amount detection by the PD does not result in a bias current setting with sufficient accuracy. To solve this issue, an electrophotographic image forming apparatus forms an electrostatic latent image pattern on a photosensitive drum, and controls the value of the bias current set for a first light emitting element based on the potential of the electrostatic latent image pattern and a detecting result of the PD.
    Type: Grant
    Filed: March 4, 2011
    Date of Patent: May 13, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Satoru Takezawa
  • Patent number: 8723910
    Abstract: An optical scanning device includes a light source, a deflector for deflecting and scanning the beams of light, an imaging optical system, a housing, a synchronization sensor, a circuit board on which the light source and the synchronization sensor are mounted, and an adjustment mechanism. The adjustment mechanism enables an adjustment of an interval between beams of light respectively emitted from the plurality of emission points on a surface to be scanned. The circuit board includes a first part on which the light source is mounted, a second part on which the synchronization sensor is mounted and an intermediate part between the first and second parts. The first part is arranged outside the housing, the second part is arranged inside the housing and the intermediate part passes through a wall surface of the housing. The adjustment mechanism fixes the light source using the housing with the interval adjusted.
    Type: Grant
    Filed: November 21, 2012
    Date of Patent: May 13, 2014
    Assignee: Kyocera Document Solutions Inc.
    Inventor: Chika Sawamoto
  • Patent number: 8670014
    Abstract: This invention has as its object to improve an image formation throughput. An image forming apparatus of this invention times a time required until an image formation is ready to start after a reference signal is output, and executes the image formation when the image formation is ready to start (for example, initial processes are complete). Furthermore, when the next reference signal is output during the image formation, the image forming apparatus executes an image formation of the next color after a waiting process based on the timed time.
    Type: Grant
    Filed: November 15, 2010
    Date of Patent: March 11, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryuhei Shoji, Hironobu Nihei
  • Patent number: 8654165
    Abstract: An optical scanning device includes: a light source that emits light rays; an aperture member that adjusts a diameter of the light rays; a deflector including a plurality of reflecting surfaces that deflect the light rays; a scanning optical system that guides a light ray, of the light rays incident on the deflector and deflected by the deflector so as to be subjected to scanning onto a to-be-scanned surface; and a synchronization detector that performs synchronization detection by using a light ray, of the light rays, reflected to the aperture from the deflector is provided.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: February 18, 2014
    Assignee: Ricoh Company, Limited
    Inventor: Naoto Watanabe
  • Patent number: 8624949
    Abstract: Methods and raster output scanner (ROS) systems are presented in which beam delay values are set for an array of ROS light sources based on wiper error and jitter error with column alignment achieved at an alignment location spaced from a center of scan (COS) location toward an end of scan location (EOS) along a fast scan range of operation of the ROS.
    Type: Grant
    Filed: March 29, 2011
    Date of Patent: January 7, 2014
    Assignee: Xerox Corporation
    Inventors: Robert Paul Herloski, Robert Kleckner, Moritz P. Wagner, Jack Lestrange, Thomas R. Race, Timothy J. Clark, Jess R. Gentner, Roger L. Triplett
  • Patent number: 8624948
    Abstract: Provided is a device for detecting a horizontal synchronization signal of an image forming apparatus. The device includes a light intensity converter to convert light intensity of a first beam emitted from a first light source and light intensity of a second beam emitted from a second light source to be different from each other, and outputting the first and second beams; a photo detector to receive the first beam and the second beam output from the light intensity converter, and outputting a first signal having a first level at a time of receiving the first beam and a second level at a time of receiving the second beam; and a horizontal synchronization signal detector to detect a horizontal synchronization signal of the first beam and a horizontal synchronization signal of the second beam by using the first signal.
    Type: Grant
    Filed: May 10, 2010
    Date of Patent: January 7, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Hyun-Jin Han
  • Patent number: 8619107
    Abstract: In a beam-spot position compensation method for use in an optical scanning device which scans a surface of a photosensitive medium by a light beam emitted by a light source, a plurality of sections are defined by dividing a scanning region on the scanned surface. An emission timing of the light beam for every section is adjusted so that a spacing between beam-spot positions corresponding to pixels of start and end of each section is changed by a predetermined amount. The sparseness or denseness of beam-spot position spacings of the plurality of sections in the whole scanning region is compensated.
    Type: Grant
    Filed: October 29, 2009
    Date of Patent: December 31, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeaki Imai, Tomohiro Nakajima
  • Patent number: 8614726
    Abstract: A light scanning unit includes a light source unit to emit a plurality of light beams, a light deflector to deflect the plurality of light beams emitted from the light source unit in a sub-scanning direction, an incident optical system to allow the plurality of light beams emitted from the light source unit to be incident on different reflection surfaces of the light deflector, and an imaging optical system that allows a plurality of light beams that are deflected by the light deflector, to be imaged on different scanning surfaces, wherein the incident optical system includes at least one incident light path changing member that folds light paths of the plurality of light beams between the light source unit and the light deflector.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: December 24, 2013
    Assignee: SAMSUNG Electronics Co., Ltd.
    Inventor: Gi-sung Park
  • Patent number: 8605130
    Abstract: An image forming apparatus includes: a plurality of optical systems, each of which includes a light-beam generating unit that generates a light beam, a rotary polygon mirror that deflects the light beam so as to scan a image carrier, and a light-beam detecting unit that detects the light beam deflected for scanning at a predetermined position on a scanning path by rotationally driving the rotary polygon mirror; a time-difference measuring unit that measures a time difference between light-beam detecting signals; a generation-timing determining unit that determines time of generation timing for generating a start signal that designates a start of an image writing operation so that the generation timing does not overlap another timing when each of the light-beam detecting signals is output from the corresponding time-difference measuring unit; and a start-signal generating unit that generates the start signal based on the time for the generation timing.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: December 10, 2013
    Assignee: Ricoh Company, Limited
    Inventor: Koichi Murota
  • Patent number: 8593495
    Abstract: An image forming apparatus that generates a synchronization signal without breaking laser diodes (LDs). The LDs output beams, which in turn are deflected to scan a photosensitive member. The synchronization signal is generated upon detecting the deflected beams. The LDs output the beams so as to generate the synchronization signal, based on which the output timing of the beams from the LDs is controlled. It is possible to select a first mode in which at least two of the LDs output the beams so as to generate the synchronization signal, and a second mode in which one of the LDs output the beams so as to generate the synchronization signal. The value of drive current supplied to at least two of the LDs when the first mode is selected is smaller than the value of drive current supplied to one of the LDs when the second mode is selected.
    Type: Grant
    Filed: December 8, 2011
    Date of Patent: November 26, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Satoru Takezawa
  • Patent number: 8587626
    Abstract: A light source control circuit of an optical writing device, admitting connection of light sources and forming an electrostatic latent image on a photosensitive element by controlling a connected light source, includes: a skew correction unit that corrects a skew of a main scanning line of an electrostatic latent image formed by the light source relative to the photosensitive element; a pattern generating unit that outputs image data for forming a predetermined pattern in an electrostatic latent image; a local deviation correction unit that corrects a local deviation of an electrostatic latent image formed by the light source on the main scanning line by acquiring image data processed to form the pattern and by performing a predetermined process; a light source control unit that causes the light source to emit light based on image data in which the local deviation has been corrected; and a setting value input unit.
    Type: Grant
    Filed: December 1, 2011
    Date of Patent: November 19, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Kunihiro Komai, Izumi Kinoshita, Tatsuya Miyadera
  • Patent number: 8581950
    Abstract: According to one embodiment, a laser controller generates a signal which corresponds to an output signal of a laser beam detection sensor before detecting an abnormality, in which the abnormality is detected, in a pseudo manner, on the basis of an output signal of a laser beam detection sensor in which the abnormality is not detected. In addition, the laser controller controls a laser unit which corresponds to the laser beam detection sensor in which the abnormality is detected, according to the generated signal.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: November 12, 2013
    Assignees: Kabushiki Kaisha Toshiba, Toshiba TEC Kabushiki Kaisha
    Inventor: Hiroyuki Fuse
  • Patent number: 8581951
    Abstract: A light scanning apparatus includes: a light emission unit emitting a first light beam and a second light beam; a motor; a rotary polygon mirror rotated by the motor, forming two scanning lines on a scan object at the same time; an optical sensor detecting the first light beam and the second light beam deflected by the rotary polygon mirror; a deviation measurement unit measuring a deviation amount of starting positions of the two scanning lines on the scan object based on a first detection timing at which the optical sensor detects the first light beam and a second detection timing at which the optical sensor detects the second light beam; and a motor control unit controlling rotation of the motor based on the second detection timing in a measurement non-execution period, and controls rotation of the motor without using the first detection timing in a measurement execution period.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: November 12, 2013
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Wataru Fujishiro, Kazushi Shumiya
  • Patent number: 8573766
    Abstract: A light source for a photo-reactive curing apparatus is provided, which includes a plurality of light source elements or modules, such as, UV or visible LEDs or LED arrays, arranged to provide a beam profile comprising irradiation zones separated by a dark zone. Photo-polymerization occurs during periods of irradiation and dark polymerization occurs during dark intervals between irradiation. The relative positioning or spacing of light source elements or modules is set to provide an exposure profile with a dark interval which matches the required dark reaction interval for optimal curing efficiency. In modular or adjustable light sources, the spacing is adjustable dependent on process parameters. For processes such as inkjet printing, the beam profile may be better matched to the ink chemistry, so as to control the polymerization reaction to meet a required process speed for single pass or multiple pass applications.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: November 5, 2013
    Assignee: Lumen Dynamics Group Inc.
    Inventors: Guomao Yang, Sheng Peng
  • Patent number: 8553061
    Abstract: An optical scanning device includes a light source device having light emitting members of a number N (N is an integer not less than 2) disposed with a tilt with respect to a sub-scan direction and a main-scan direction, a deflecting device for scanningly deflecting light beams of the number N from the light emitting members, an input optical system for directing the light beams from the light source means to the deflecting device, an imaging optical system for directing the deflected light beams to a surface to be scanned, a synchronism signal detecting device for detecting a portion of a light beam scanningly deflected by the deflecting surface and producing writing start timing signals for the light beams upon the surface to be scanned, and a synchronism detecting optical system for directing the deflected light beams to the synchronism signal detecting device, wherein the synchronism signal detecting device detects a light beam emitted from a light emitting member among the light emitting members of the n
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: October 8, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Genichiro Kudo
  • Patent number: 8547409
    Abstract: A light emission control device images an electrostatic latent image on a photosensitive element by a plurality of light emitting elements corresponding to a line in a second direction perpendicular to a first direction which is a rotational direction the photosensitive element. The light emission control device includes: a detecting unit that detects a rotational position of the photosensitive element, in the first direction, corresponding to a line in the second direction; an acquiring unit that acquires a distance between the light emitting elements and the rotational position of the photosensitive element in the first direction detected by the detecting unit; and a control unit that controls light emission by the light emitting elements according to the distance acquired by the acquiring unit and corrects a fluctuation in a density of a visible image converted from the electrostatic latent image.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: October 1, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Takuhei Yokoyama, Izumi Kinoshita, Kunihiro Komai, Tatsuya Miyadera, Yoshinori Shirasaki, Takeshi Shikama, Akinori Yamaguchi
  • Patent number: 8525865
    Abstract: An optical scanning apparatus includes a housing, light source, deflector, imaging lens, reflective mirrors, a synchronization detector and synchronization detection mirror. The housing has a plate to partition the housing. The deflector deflects a light beam emitted from the light source. The imaging lens converts the deflected light beam into a constant speed scanning light beam. The reflective mirrors reflect the constant speed scanning light beam to a photoreceptor. The synchronization detector detects timing for starting scanning of the photoreceptor. The synchronization detection mirror reflects the light beam to the synchronization detector. At least one of the reflective mirrors is disposed midway in a synchronization detection light path extending from the deflector to the synchronization detection mirror. The light beam reflected by the synchronization detection mirror is reflected again by at least one of the reflective mirrors, such that the light beam is guided to the synchronization detector.
    Type: Grant
    Filed: May 25, 2011
    Date of Patent: September 3, 2013
    Assignee: Kyocera Document Solutions Inc.
    Inventor: Hironobu Ooi
  • Publication number: 20130201270
    Abstract: An optical scanning apparatus, including: a deflector including deflection surfaces and configured to deflect, by the deflection surfaces, light beams respectively emitted from light emitting portions for scanning in a main scanning direction; an imaging optical system configured to guide the light beams deflected for scanning by the deflection surfaces to a surface to be scanned; a light source including the light emitting portions arranged so as to be separated from each other in a sub-scanning direction perpendicular to the main scanning direction and an optical axis direction of the imaging optical system; and a controller configured to control the light source in such a manner that a difference between scanning start timings of the light beams at two adjacent deflection surfaces among the deflection surfaces is different from a difference between scanning start timings of the light beams at other two adjacent deflection surfaces among the deflection surfaces.
    Type: Application
    Filed: February 4, 2013
    Publication date: August 8, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: CANON KABUSHIKI KAISHA
  • Patent number: 8477169
    Abstract: An optical writing device includes two or more light sources. The two or more light sources can be driven independently, are placed away from each other in a sub-scanning direction of a photoreceptor, and each distance of beams emitted from the light sources to the photoreceptor is different. A phase control unit causes a difference in phase among timing control data of two or more beams emitted from the two or more light sources by a phase change amount, which is determined on the basis of beam position of the each beam on the photoreceptor in a main scanning direction and varies depending on the beam position. The modulating unit modulates the timing control data of the respective phase-controlled beams by a same clock.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: July 2, 2013
    Assignee: Ricoh Company, Limited
    Inventor: Toshio Ohide
  • Patent number: 8446444
    Abstract: A deflector deflects a light beam emitted from a light source including a plurality of light-emitting units. A scanning optical system focuses the light beam deflected by the deflector on a scanning target surface. A monitoring photoreceiver receives a part of a light beam deflected by the deflector and directed toward an area within a scanning area outside an image area. A detecting unit individually detects emission powers of at least two light-emitting units based on an output signal of the monitoring photoreceiver in a single sweep of scanning.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: May 21, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaaki Ishida, Yasuhiro Nihei, Atsufumi Omori, Dan Ozasa, Jun Tanabe
  • Patent number: 8416272
    Abstract: In an electrophotographic (EP) device, methods and apparatus include determining a delay of one or more sensors (hsync) to accurately know when to start the process of scanning latent images. In one aspect, the sensor includes a leading and trailing edge defined along a direction of laser beam scan travel. Determining the delay includes learning a position of a laser beam on the sensor at a time when a controller connected to the sensor receives a signal from the sensor indicating the sensor is being sufficiently impinged upon by the laser beam. It also includes learning a latest possible position of the laser beam along the direction of laser scan travel where the laser beam can be turned on and still have the sensor assert a signal indicating it has been sufficiently impinged upon by the laser beam. Bi-directionally scanning EP devices are also disclosed, including controllers, photoconductors, sensors, etc.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: April 9, 2013
    Assignee: Lexmark International, Inc.
    Inventors: David J. Mickan, Eric W. Westerfield, Daniel E. Pawtey
  • Patent number: 8400488
    Abstract: An optical scanning apparatus capable of properly correcting a main scanning scale factor. Upstream and downstream laser-light detection sensors of the optical scanning apparatus each generate a signal when first or second light beam passes through each of slits formed in the sensors. Based on signals, a scanning time required for each light beam to scan between the sensors is measured. A correction coefficient is decided by a correction value calculation unit based on a difference between wavelengths of the first and second light beams, a scanning time difference is calculated by a comparison unit based on the correction coefficient and scanning times of the light beams, and the downstream laser-light detection sensor is rotated by a sensor rotation drive unit to make the scanning time difference zero, whereby the slits are made parallel to each other.
    Type: Grant
    Filed: July 20, 2011
    Date of Patent: March 19, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Noriyuki Chino, Katsuhiko Takano, Shoji Kanemura, Junji Yasuda, Kota Kiyama
  • Patent number: 8379279
    Abstract: According to this invention, the image attribute is determined by determining whether the image of each color component of color image data having undergone a screen process is a continuous tone image, and whether the image of each color component is a pattern image. Whether to perform an interpolation process is determined for each color component based on the attribute determination result of each color component. If it is determined that the images of all the color components are pattern images, interpolation determination results do not coincide with each other, and there is a color component determined to represent a continuous tone image, the interpolation determination result of this color component is overwritten with the interpolation determination result of the remaining color components. The interpolation process is executed in accordance with the interpolation determination result.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: February 19, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yoko Ido