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. 25, 2000
Filed:
Aug. 01, 1997
Mark D Peterson, Lake Oswego, OR (US);
Jeffrey A Gohman, Hillsboro, OR (US);
In Focus Systems, Inc., Wilsonville, OR (US);
Abstract
An image projector has an optical path including, from upstream to downstream, a light source, a light pipe, a polarization conversion prism, a positive lens group and a light valve. The light pipe has an outlet and an inlet, and is constructed to receive light from the light source and to produce a unique projection display format as light is transmitted therethrough. The polarization conversion prism recycles light to optimize the amount of light that is properly polarized in the system. The positive lens group includes at least one positive lens positioned downstream of the polarization conversion prism. The positive lens group images the outlet of the light pipe onto the light valve.