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:
Sep. 07, 1999
Filed:
Jun. 24, 1996
Motoo Koyama, Kawasaki, JP;
Hideaki Shimomura, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Reflective spatial light modulators (RSLMs) and projection apparatus employing such RSLMs are disclosed. The RSLM comprises a reflective surface and a superposed light-modulation layer. The reflective surface is configured to have a reflective diffraction optical element or a microfaceted reflective array. Incident light impinging on the RSLM can pass through the light-modulation layer, reflect from the reflective surface, and return through the light-modulation layer to become modulated signal light capable of forming a viewable image if projected onto a screen or other surface. The reflective diffraction optical element or microfaceted reflective array on the reflective surface is operable to cause the signal light to propagate from the RSLM in a different direction than any ghost light reflected from the RSLM. Projection apparatus employing such an RSLM comprise an illumination optical system, a projection optical system that may or may not be coaxial with the illumination optical system, and a stop operable to pass signal light but not ghost light to a screen for viewing. The viewed image has enhanced contrast over the prior art.