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:
Jul. 08, 2003
Filed:
Dec. 10, 2001
Francisco Castro, St. Charles, IL (US);
Austin Harton, Oak Park, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A double sampling time-integrating pixel sensor having a photo-detector, a capacitor, a comparator and two pixel data buffers. In operation, the photo-current from the photo-detector charges the capacitor and produces a photo-voltage. The photo-voltage sensed by the capacitor and a first reference voltage are compared by the comparator. When the photo-voltage exceeds the first reference voltage, a first global counter value is latched into the first pixel data buffer. When the photo-voltage exceeds a second reference voltage, a second global counter value is latched into the second pixel data buffer. The optical power falling on the photo-detector is determined from the difference between the second and first counter values. An array of sensors is incorporated into a semiconductor device together with circuitry to read and decode the pixel data buffers.