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:
Jun. 14, 2005
Filed:
Jul. 30, 2002
Clifford I. Drowley, Scottsdale, AZ (US);
Clifford I. Drowley, Scottsdale, AZ (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A distance measuring device and photosensor circuit are disclosed herein. By pulsing a light source such as an LED to illuminate an object and measuring the phase difference between the light reflected from the object and the original phase of the light source, the distance to an object may be determined. In order to measure the phase difference, a CMOS photosensor or photosensor array may be used to receive the reflected light and store charge generated during different portions of time in different storage nodes or pixel cells. The difference between the amount of charge stored in different storage nodes can be used to determine the phase difference between the original light illuminating the object and the light reflected from the object. This phase difference can in turn be used to determine the distance to the object.