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Improving the Efficiency and Image-Uniformity of a Simple Reflective Light Valve Projector

IP.com Disclosure Number: IPCOM000054878D
Original Publication Date: 1980-Apr-01
Included in the Prior Art Database: 2005-Feb-13

Publishing Venue

IBM

Related People

Authors:
Dewey, AG [+details]

Abstract

An improved system for projecting a reflective light valve is shown in Fig. 1. The system 10 includes a projection lamp 12, condenser lenses 14 and 16, a beam-splitter 18, a reflective light valve 20, a projection lens 22 and a screen (not shown). In this type of system a 50/50 beam-splitter 18 is normally used. Consequently, a maximum of only 25 percent of the light delivered by condenser 16 can reach the screen. Another problem which is common to many projection systems is that there is a significant decrease in illuminance from the center to the edges of the screen.