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:
Dec. 29, 1998
Filed:
Feb. 23, 1998
Richard Billings Merrill, Daly City, CA (US);
Foveonics, Inc., Cupertino, CA (US);
Abstract
The accuracy of an active pixel sensor cell is increased by utilizing a reset diode in lieu of the reset transistor that is conventionally used to reset the voltage on the photodiode of the cell. The reset diode, which is largely unaffected by 1/f noise, consistently resets the photodiode to a substantially constant voltage as opposed to the reset transistor which varies the reset voltage on the photodiode across integration periods due to the effect of 1/f noise. In the present invention, the photodiode is formed by forming a well region of a second conductivity type in a substrate of a first conductivity type. The reset diode is then formed by forming a reset region of the first conductivity type in the well region.