IMAGE PROJECTION SYSTEM WITH A POLARIZING BEAM SPLITTER

• Main Authors: HANSEN, DOUGLAS P, LUND, MARK W, GARDNER, ERIC, PERKINS, RAYMOND T
• Format: Patent
• Language: English; French
• Published: 08.02.2001
• Edition: 7
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; CINEMATOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; ELECTROGRAPHY; FREQUENCY-CHANGING; HOLOGRAPHY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHOTOGRAPHY; PHYSICS; PICTORIAL COMMUNICATION, e.g. TELEVISION; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

An image projection system having a wire grid polarizing beam splitter (4) which functions as both the polarizer and the analyzer in the system. A ligh t source (20) produces a light beam directed at the beam splitter (14) which reflects one polarization and transmits the other. A liquid crystal array (2 6) is disposed in either the reflected or transmitted beam. The array modulates the polarization of the beam, encoding image information thereon, and direct s the modulated beam back to the beam splitter. The beam splitter again reflec ts one polarization and transmits the other so that the encoded image is either reflected or transmitted to a screen (25). The wire grid polarizing beam splitter is capable of being oriented at various angles with respect to the source light beam and modulated beam, and accepts relatively divergent light .