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:
Apr. 08, 2003
Filed:
Jul. 19, 2000
Gregg S. Goyins, Lincoln, CA (US);
Hewlett Packard Development Company, L.P., Houston, TX (US);
Abstract
One embodiment of the invention is a digital filter that avoids image flicker in a projection display that has two operational modes. This digital filter avoids undesired intensity variations between successive frames by changing all the assigned pixel values by the same amount during either of the two modes. This digital filter typically only needs to correct some of the least significant bits (“LSB's”) of the pixel values during either operational mode. This is because the dynamic range of the flicker is often very limited (e.g., it is often less than 5%). In fact, some embodiments combine the flicker-filtering function with the dither-control function, if the correction of a LSB causes an over correction of the flicker problem.