Patents by Inventor Tetsuo Hohki

Tetsuo Hohki 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).

  • Patent number: 4799175
    Abstract: Printed wiring boards (PWBs) applied to this inspection system are previously formed with marks in prescribed positional relation to wiring patterns. Deviation of PWBs with respect to absolute coordinates of the inspection system is detected by reading the marks. The PWBs are sequentially set one by one on a movable table, to be subjected to image acquisition of the marks and inspected areas. A first PWB is image-acquisited whereby obtained binary image data of the inspected area are stored in a memory unit. Thereafter a second PWB is image-acquisited, and in advance to the image acquisition of its inspected area, relative misregistration of the both PWBs is found by deviation data on respective marks of the first and second PWBs. The binary image data of the first PWB is read from the memory unit on the basis of the binary image data of the second PWB. When the binary image data of the first PWB are read, positional correction, i.e.
    Type: Grant
    Filed: May 10, 1985
    Date of Patent: January 17, 1989
    Assignee: Dainippon Screen Mfg., Co.
    Inventors: Tetsuo Sano, Tetsuo Hohki, Eiji Kodama, Takumi Yoshida, Masafumi Kawatani, Hisayuki Tsujinaka
  • Patent number: 4682040
    Abstract: Disclosed herein is an image pickup apparatus for a printed wiring board comprising a solid state image sensor whose light receiving surface is set to be opposed to the surface of the printed wiring board, a main illumination source arranged to satisfy the law of regular reflection on the surface of the printed wiring board with respect to the light receiving surface of the solid state image sensor and a subsidiary illumination source arranged not to satisfy the law of regular reflection with respect to the light receiving surface of the solid state image sensor thereby to supply the light receiving surface with scattering light by strias formed on copper patterns.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: July 21, 1987
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Tetsuo Hohki, Tetsuo Sano, Eiji Kodama, Hisayuki Tsujinaka
  • Patent number: 4555180
    Abstract: An improved apparatus for measuring the printed area of a printing plate upon which a printing image is formed, of the type having a movable scanning head provided with longitudinally arranged light sources and plural photosensors arranged in parallel with the light sources. The improvement is composed of a proving sensor device separate from and movable independently of the scanning head which includes at least one light source and photosensor. The proving sensor device provides calibration data for correcting the measurements made by the scanning head. It does this by measuring the intensity of reflected light from a totally dark printing area and a non-printing area from anywhere on the printing plate, and a totally reflective surface and totally absorptive surface, which are preferably located apart from the printing plate. The improvement further includes control means for electronically processing the measurement data produced by both the scanning head and proving sensor device.
    Type: Grant
    Filed: March 18, 1983
    Date of Patent: November 26, 1985
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Tatsunosuke Masuda, Tetsuo Hohki, Yasuo Kurusu
  • Patent number: 4367926
    Abstract: A method for stabilizing the intensity of a light beam emitted by a light source and deflected by an acoustooptical deflector element which is controlled by a control signal and is arranged in a scanning exposure head, without regard to deflection angles, wherein a detected light beam intensity is compared with a predetermined reference light intensity. The difference between the light beam intensity and the reference light intensity is detected, and wherein the control signal corresponding to the detected difference is controlled by a stored correction signal which is read out of a memory, so that the intensity of the light beam through the acoustooptical deflector element may be maintained at a certain level.
    Type: Grant
    Filed: June 13, 1980
    Date of Patent: January 11, 1983
    Assignee: Dainippon Screen Seizo Kabushiki Kaisha
    Inventor: Tetsuo Hohki
  • Patent number: 4310234
    Abstract: A method for determining a supplementary amount of a developing solution for use in a film developer, wherein values of width signals for controlling a halftone dot generator of a picture reproducing machine are counted up, while a reproduction picture is recorded on a photosensitive film by the halftone dot generator according to picture signals which are obtained by scanning an original picture photoelectrically, and wherein a supplementary amount of the developing solution is determined according to the counted-up total value of the width signals prior to the development of the photosensitive film.
    Type: Grant
    Filed: September 22, 1980
    Date of Patent: January 12, 1982
    Assignee: Dainippon Screen Seizo Kabushiki Kaisha
    Inventors: Seiya Sakamoto, Isao Saito, Makoto Hirosawa, Tetsuo Hohki
  • Patent number: 4251625
    Abstract: A spot of light is formed upon a photosensitive material which is moved in a scanning direction, and the spot is vibrated to and fro along a vibration direction at a considerable angle to the scanning direction, and the amplitude of vibration, and the center of the vibration path, are controlled so that the spot exposes areas on the photosensitive material which form half-tone dots.
    Type: Grant
    Filed: October 26, 1978
    Date of Patent: February 17, 1981
    Assignee: Dainippon Screen Seizo Kabushiki Kaisha
    Inventors: Seiya Sakamoto, Tetsuo Hohki
  • Patent number: 4232344
    Abstract: A device for reproducing a halftone picture by scanning, representing a marked simplification over conventional devices of this type. The recording beam is controlled by two deflection means and an aperture of simple shape and the control means allows dot patterns with a screen angle to be produced very simply.
    Type: Grant
    Filed: November 28, 1978
    Date of Patent: November 4, 1980
    Assignee: Dainippon Screen Seizo Kabushiki Kaisha
    Inventors: Seiya Sakamoto, Tetsuo Hohki, Isao Saito