Patents by Inventor Keng Chang

Keng Chang 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).

  • Publication number: 20070138378
    Abstract: An optical navigation sensor receives light that is produced by a light source and reflected from a surface. The optical navigation sensor has a silicon substrate having a plurality of photo-sensing regions, each of which receives a portion of the reflected light, and each of which provides a pixel of navigation information. At least one layer of material is deposited on the photo-sensing regions of the silicon substrate during a silicon wafer fabrication process. Each layer has a thickness that causes it to serve as an anti-reflection coating and reduce a percentage of light that is reflected away from the photo-sensing regions of the silicon substrate. A circuit biases each of the photo-sensing regions with a current, the current providing a given responsivity, and the current being less than a current that would be required to provide the given responsivity absent the at least one layer of material.
    Type: Application
    Filed: December 20, 2005
    Publication date: June 21, 2007
    Inventor: Keng Chang