Patents by Inventor Tomoaki Yoshida, deceased

Tomoaki Yoshida, deceased 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).

  • Optical line printhead and an LED chip used therefor
    Patent number: 5684523
    Abstract: A light emitting diode chip includes a substrate carrying thereon a number of light emitting diodes aligned in a row to form an array for producing a number of optical beams parallel to each other in a first direction, and monitoring element provided monolithically on the substrate for detecting the power of the optical beams produced by the light emitting diodes, wherein the monitoring element includes: a reference light emitting diode having a structure identical to the light emitting diodes in the array for producing an optical beam in a second direction perpendicular to the first direction; and a photodiode having a structure identical to the light emitting diodes in the array and separated from the reference light emitting diode by an isolation groove for detecting the optical beam produced by the reference light emitting diode.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: November 4, 1997
    Assignees: Ricoh Company, Ltd., Ricoh Research Institute of General Electronics Co., Ltd.
    Inventors: Shunichi Satoh, Takashi Takahashi, Hiroyuki Iechi, Tomoaki Yoshida, deceased, Chizuru Yoshida, legal representative, Hirokazu Iwata, Takaaki Miyashita