Patents by Inventor Hiroaki Jo

Hiroaki Jo has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20090147512
    Abstract: A light emitting device includes a plurality of light emitting elements aligned along a reference line, a plurality of lenses that collects light emitted from the plurality of light emitting elements, and a drive circuit that allows either a first light emitting element or a second light emitting element to emit light. The plurality of lenses includes a first lens and a second lens that is disposed on an opposite side of the first lens with the reference line interposed therebetween, and a distance between the center of the first lens and the reference line is the same as a distance between the center of the second lens and the reference line. The plurality of light emitting elements includes the first light emitting element and the second light emitting element that is disposed on an opposite side of the first light emitting element with the reference line interposed therebetween.
    Type: Application
    Filed: December 2, 2008
    Publication date: June 11, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroaki JO
  • Publication number: 20090140631
    Abstract: A light-emitting device includes four or more rows of element groups each having light-emitting elements arranged in a first direction, the element groups being arranged in parallel in a second direction different from the first direction. In each of a plurality of unit regions arranged in the first direction, the light-emitting elements belonging to the four or more rows of element groups are arranged at different positions by ones. The four or more rows of element groups includes a first element group, a second element group, and a third element group adjacent to the second element group.
    Type: Application
    Filed: November 7, 2008
    Publication date: June 4, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroaki JO
  • Publication number: 20090140265
    Abstract: A light emitting device includes a substrate having transparency, a light emitting element that emits light at least to the substrate side, and a light detecting element that is formed between the light emitting element and the substrate. The light detecting element is formed along an outer frame of the light emitting element in a plan view.
    Type: Application
    Filed: November 12, 2008
    Publication date: June 4, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tsukasa EGUCHI, Hiroaki JO, Eiji KANDA, Toshiyuki KASAI, Atsushi ITO
  • Publication number: 20090140658
    Abstract: There is provided a method of driving a light emitting device including a light emitting element and a unit circuit that is disposed in correspondence with the light emitting element and drives the tight emitting element in accordance with emission control data generated based on image data, wherein the light emitting device has a temperature sensor and a light receiving sensor. The method includes detecting the temperature of the light emitting device by using the temperature sensor, detecting light emitted from the light emitting element by using the light receiving sensor, and generating the emission control data by correcting the image data in response to the temperature of the light emitting device which is detected by the temperature sensor and the detected value of light which is detected by the light receiving sensor.
    Type: Application
    Filed: December 1, 2008
    Publication date: June 4, 2009
    Applicant: Seiko Epson Corporation
    Inventors: Hiroaki JO, Tsukasa EGUCHI, Eiji KANDA, Toshiyuki KASAI
  • Patent number: 7542031
    Abstract: To reduce the variation of luminance between driving modules. Driving modules DR1 to DR3 each have monitor current output circuits, and output monitor current signals MI12, MI21, MI22, and MI31. A monitor unit of a control circuit converts the monitor current signals into monitor data D12, D21, D22, and D31, respectively, and supplies them to a control data generating unit. The control data generating unit generates current control data CTL1 to CTL3 such that the values of the respective monitor current signals are equal to each other and supplies them to the driving modules DR1 to DR3.
    Type: Grant
    Filed: April 13, 2005
    Date of Patent: June 2, 2009
    Assignee: Seiko Epson Corporation
    Inventors: Hiroaki Jo, Toshiyuki Kasai
  • Publication number: 20090122090
    Abstract: To adjust brightness of an electro-optic device for each pixel. A data line driving circuit includes a DAC for generating a gray-scale current according to gray-scale data representing gray-scales of pixels, and a DAC for generating a correction current for correcting the brightness of the pixels. The data line driving circuit generates a voltage according to a current obtained by adding the correction current generated in the DAC to the gray-scale current in the DAC and applies the generated voltage to each data line.
    Type: Application
    Filed: January 12, 2009
    Publication date: May 14, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hiroaki Jo, Toshiyuki Kasai, Takeshi Nozawa
  • Publication number: 20090115769
    Abstract: To simplify s configuration of a current mode DA converter. A data line driving circuit includes DA converting units U1 to Un. Each DA converting unit U1 to Un a voltage DA converting circuit for generating an analog voltage signal Sv based on image data, a V/I converting circuit for converting the analog voltage signal Sv into an analog current signal Si, and a voltage current selector for selecting one of the analog voltage signal Sv and the analog current signal Si based on a pre-charge control signal CTL. In addition, the analog voltage signal Sv outputted from the voltage current selector serves as a pre-charge voltage, and the analog current signal Si serves as a driving current of an OLED element.
    Type: Application
    Filed: December 23, 2008
    Publication date: May 7, 2009
    Applicant: Seiko Epson Corporation
    Inventors: Hiroaki Jo, Toshiyuki Kasai
  • Publication number: 20090066676
    Abstract: A data line driving circuit includes a plurality of blocks that are cascaded together, wherein each of the plurality of blocks includes a shift register that sequentially outputs a plurality of selection signals for each block in synchronization with a clock signal; a data synchronization circuit that adjusts a phase of a data signal in which a plurality of items of data are arranged chronologically by using the clock signal as a reference and to output the data signal to a block of the next stage; a data expansion circuit that expands the items of data of the data signal after being adjusted by the data synchronization circuit into a plurality of systems on the basis of the plurality of selection signals; and a signal generation circuit that generates a driving signal corresponding to each item of data after being expanded by the data expansion circuit.
    Type: Application
    Filed: July 29, 2008
    Publication date: March 12, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroaki JO
  • Patent number: 7502002
    Abstract: To accurately display a predetermined gray level. A first transistor T1 and a second transistor T2 are arranged in a first path 501 from a power line 41 to a constant-current circuit 301. A driving transistor Tdr and a current supply transistor Tc are arranged in a second path 502 from the power line 41 to an OLED element 51. A capacitor C1 connected to the gate of the driving transistor and a capacitor C2 connected to the gate of the current supply transistor Tc hold a voltage corresponding to a data current Idata-j flowing in the first path 501. The driving transistor Tdr controls a driving current flowing in the second path 502 in accordance with the voltage held in the capacitor C1. The current supply transistor Tc controls the driving current flowing in the second path 502 in accordance with the voltage held in the capacitor C2.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: March 10, 2009
    Assignee: Seiko Epson Corporation
    Inventors: Hiroshi Horiuchi, Hiroaki Jo
  • Publication number: 20090033687
    Abstract: A signal processing unit that generates data signals for controlling gray-scale levels of electro-optical elements includes a first D/A conversion unit that generates gray-scale signals from gray-scale data for designating the gray-scale levels of the electro-optical elements; a storage unit that stores correction data indicating correction values with respect to the gray-scale signals; a second D/A conversion unit that has resolution different from that of the first D/A conversion unit, and that generates correction signals from the correction data stored in the storage unit; and a synthesizing unit that synthesizes the gray-scale signals generated by the first D/A conversion unit with the correction signals generated by the second D/A conversion unit to generate the data signals.
    Type: Application
    Filed: September 23, 2008
    Publication date: February 5, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Toshiyuki Kasai, Hiroaki Jo, Takeshi Nozawa, Hiroshi Horiuchi
  • Patent number: 7486285
    Abstract: To simplify s configuration of a current mode DA converter. A data line driving circuit includes DA converting units U1 to Un. Each DA converting unit U1 to Un a voltage DA converting circuit for generating an analog voltage signal Sv based on image data, a V/I converting circuit for converting the analog voltage signal Sv into an analog current signal Si, and a voltage current selector for selecting one of the analog voltage signal Sv and the analog current signal Si based on a pre-charge control signal CTL. In addition, the analog voltage signal Sv outputted from the voltage current selector serves as a pre-charge voltage, and the analog current signal Si serves as a driving current of an OLED element.
    Type: Grant
    Filed: April 13, 2005
    Date of Patent: February 3, 2009
    Assignee: Seiko Epson Corporation
    Inventors: Hiroaki Jo, Toshiyuki Kasai
  • Patent number: 7453383
    Abstract: A digital-to-analog converting circuit is provided that is capable of, after converting digital data into an analog current, correcting the current value based on digital current correction data without any complex processing. The exemplary digital-to-analog converting circuit can include a first digital-to-analog converting circuit portion and a second digital-to-analog converting circuit portion. First digital data (image data) can input to the first digital-to-analog converting circuit portion, and second digital data (current correction data) can input to the second digital-to-analog converting circuit portion. After the first digital-to-analog converting circuit portion converts the image data into a first analog current, the second digital-to-analog converting circuit portion can correct the first analog current based on the current correction data, and outputs the corrected current as a second analog current.
    Type: Grant
    Filed: September 27, 2005
    Date of Patent: November 18, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Hiroaki Jo
  • Patent number: 7443540
    Abstract: A signal processing unit that generates data signals for controlling gray-scale levels of electro-optical elements includes a first D/A conversion unit that generates gray-scale signals from gray-scale data for designating the gray-scale levels of the electro-optical elements; a storage unit that stores correction data indicating correction values with respect to the gray-scale signals; a second D/A conversion unit that has resolution different from that of the first D/A conversion unit, and that generates correction signals from the correction data stored in the storage unit; and a synthesizing unit that synthesizes the gray-scale signals generated by the first D/A conversion unit with the correction signals generated by the second D/A conversion unit to generate the data signals.
    Type: Grant
    Filed: July 13, 2005
    Date of Patent: October 28, 2008
    Assignee: Seiko Epson Corporation
    Inventors: Toshiyuki Kasai, Hiroaki Jo, Takeshi Nozawa, Hiroshi Horiuchi
  • Publication number: 20080224755
    Abstract: A level shift circuit that converts a level of an input signal having a logic level at a first input electric potential and a logic level at a second input electric potential and that generates an output signal having a logic level at a first output electric potential corresponding to the first input electric potential and a logic level at a second output electric potential corresponding to the second input electric potential.
    Type: Application
    Filed: February 29, 2008
    Publication date: September 18, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroaki JO
  • Patent number: 7375711
    Abstract: To provide a method for manufacturing an electro-optical device that is capable of controlling more smoothly brightness as compared with a control in every one frame and preventing large current from flowing when switching frames in a peak brightness control, a method of driving the same, and an electronic apparatus. A grayscale data average value operation unit 33 performs, for each line, an average value calculation of grayscale levels of images corresponding to images of an one-frame-length and outputs, based on average value for the one frame-length, mode signals M1 to M4 for brightness control in each line. A driver input data converter 34 rewrites, based on the mode signals M1 to M4 from the grayscale data average value operation unit 33, grayscale data HD for one line among grayscale data from a frame memory 31 into grayscale data DD. The driver input data converter 34 outputs grayscale data DD which is image data for the one frame-length and whose brightness is adjusted in a signal generating circuit.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: May 20, 2008
    Assignee: Seiko Epson Corporation
    Inventors: Hiroshi Horiuchi, Hiroaki Jo, Toshiyuki Kasai
  • Publication number: 20080111878
    Abstract: A control method for controlling an optical head having a plurality of light emitting devices, includes: dividing the plurality of light emitting devices into a plurality of blocks by grouping adjacent light emitting devices of the plurality of light emitting devices; adjusting levels of driving signals supplied to the adjacent light emitting devices for each of the plurality of blocks so that emission luminances of the adjacent light emitting devices belonging to the each of the plurality of blocks become substantially equal to each other; and adjusting emission periods so that the equalized emission luminances of the plurality of blocks become substantially equal to each other.
    Type: Application
    Filed: October 17, 2007
    Publication date: May 15, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Shinsuke FUJIKAWA, Hiroaki JO
  • Publication number: 20080079669
    Abstract: Disclosed herein is a light-emitting device including: a plurality of light-emitting elements which emit light with light intensities according to the levels of driving currents; a plurality of current generation circuits which are provided in correspondence with the plurality of light-emitting elements, have a plurality of current sources, and combine currents output from the plurality of current sources to output the combined currents as the driving currents; and a plurality of memories which store control signals for controlling the currents output from the plurality of current sources; wherein the levels of the currents of the plurality of current sources are different from one another, and wherein at least one of the plurality of memories is commonly connected to the current sources corresponding to predetermined current in at least two of the plurality of current generation circuits.
    Type: Application
    Filed: September 14, 2007
    Publication date: April 3, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hiroaki JO, Shinsuke FUJIKAWA
  • Patent number: 7348942
    Abstract: To enhance the display characteristics of moving images and enhance the display quality in an electro-optical device using electro-optical elements that emit light with the brightness in accordance with a driving current, a pixel includes a driving transistor T4 for setting a driving current Ioled in accordance with data stored in a capacitor and an organic EL element OLED that emits light with the brightness in accordance with the driving current Ioled. During a period of time from the moment in which the scanning line corresponding to the pixel in which data is to be written to the moment in which the same scanning line is selected again, at least one of the electric potential of a first power supply line and the electric potential of a second power supply line is set to be variable and a forward bias and a reverse bias are alternately and repeatedly applied to the organic EL element OLED.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: March 25, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Hiroaki Jo
  • Publication number: 20080048945
    Abstract: An electro-optical device includes a plurality of unit circuits that are arranged therein. Each of the plurality of unit circuits includes an electro-optical element that has a gray-scale level according to a current value of a driving current, a reference setting unit that generates a reference signal having a level according to correction data of the unit circuit, and a current control unit that controls the driving current to be supplied to the electro-optical element to a current value according to gray-scale data assigning a gray-scale level of the unit circuit and the level of the reference signal generated by the reference setting unit.
    Type: Application
    Filed: December 28, 2006
    Publication date: February 28, 2008
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hiroaki JO, Shinsuke FUJIKAWA
  • Patent number: 7319444
    Abstract: To prevent degradation of quality of a displayed image by maintaining the flow of current at a constant value even when organic EL elements are degraded, a pixel circuit includes a capacitor that accumulates, when a scanning line is selected, charge in accordance with current flowing through a data line; a TFT that allows, subsequent to the selection, current I2 in accordance with the accumulated charge to flow between the source and drain of the TFT; an organic EL element whose anode is connected to the drain of the TFT; a TFT that detects a voltage applied to the organic EL element and allows current I3 in accordance with the applied voltage to flow between the source and drain of the TFT; and a correction circuit that generates mirror current I4 of the current I3 and adds the current I4 to the current I2.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: January 15, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Hiroaki Jo