The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 25, 2005
Filed:
Nov. 10, 2000
Sukeyuki Shinotsuka, Sayama, JP;
Katsuhiko Takebe, Sayama, JP;
Sukeyuki Shinotsuka, Sayama, JP;
Katsuhiko Takebe, Sayama, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A photo-sensor circuit according to an embodiment of the present invention comprises a photo-detecting element (PD) for detecting a light signal and converting the same signal into an electric signal, a first MOS transistor (QT) for charging and discharging parasitic capacitance (C), a capacitor (C) for accumulating a terminal voltage of the photo-detecting element as a pixel signal, a second MOS transistor (Q) for transferring a parasitic capacitance charge from the photo-detecting element to the capacitor (C), a third MOS transistor (Q) for amplifying the terminal voltage of the capacitor and a fourth MOS transistor (Q) for selectively outputting an amplified pixel signal. In the above structure, the first MOS transistor and the second MOS transistor are turned ON for a certain period of time before accumulation of a pixel signal to equalize terminal voltages of the photo-detecting element and the capacitor by charging and discharging the parasitic capacitance of the photo-detecting element and the capacitor, the second MOS transistor is turned OFF and the capacitor is open after a certain period of time of accumulation of the pixel signal and then the fourth MOS transistor is switched ON. This photo-sensor circuit offers an advantageous feature of producing a pixel signal having high reproducibility.