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Image projection system
   
Document Number
US Patent 5879067
Issued Date
March 9, 1999
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Abstract
A projection beam supplied by a projector is incident on a beam splitter in the form of a cholesteric filter. The cholesteric filter reflects circularly polarized radiation having a wavelength which corresponds to the pitch of the molecular helix and having a direction of rotation which corresponds to the direction of the molecular helix to a reflector. The circular direction of polarization reflected by the cholesteric filter is inverted on the reflector so that the beam is subsequently passed to the screen by the cholesteric filter.
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Number of Claims:
18
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Owner
Published
March 9, 1999
Application Number
08/846,928
Filed
April 30, 1997
US Classification
353/98   353/77
Int'l Classification
G03B   21/10   (20060101)   H04N   5/74   (20060101)  
Examiner
Attorney/Law Firm
Parent Case
This application is a divisional of 08/248,945, filed May 24, 1994 and now U.S. Pat. No. 5,573,324.
USPTO Field of Search
353/20   353/31   353/78   353/77   353/74   353/84   353/98   359/101   359/105   359/629   359/634   359/639   348/761   348/762   348/766   348/767  
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Claims
Description
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