[54] POLARIZER HAVING A GLASS SUBSTRATE WITH FILMS ON EITHER SIDE WITH DIFFERENT WAVELENGTH CHARACTERISTICS AND PROJECTION DISPLAY USING SAME
[75] Inventors: Shinya Sannohe; Yoshito Miyatake,
both of Neyagawa, Japan
[73] Assignee: Matsushita Electric Industrial Co., Ltd., Osaka-Fu, Japan
[21] Appl. No.: 218,957
[22] Filed: Mar. 28,1994
[30] Foreign Application Priority Data
Apr. 1, 1993 [JP] Japan 5-075471
[51] Int. CI.6 G02F 1/1335; G02B 1/10;
G02B 5/28
[52] U.S. CI 359/63; 359/41; 359/583;
359/590; 359/49
[58] Field of Search 359/40, 41, 42,
359/48, 49, 583, 589, 590, 487, 502, 634, 629, 638, 639, 640, 831, 832, 837, 353
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4,969,730 11/1990 van den Brandt.
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Primary Examiner—William L. Sikes
Assistant Examiner—Kenneth Parker
Attorney, Agent, or Firm—Panitch Schwarze Jacobs &
Nadel, P.C.
[57] ABSTRACT
A polarization separation mirror is made by evaporationdepositing a first multi-layers thin film and a second multilayers thin film respectively on both surfaces of a transparent substrate, the mirror acts as a polarization beam splitter by cementing it between two transparent prism bodies. By shifting the relative film thicknesses of the first multi-layers thin film and of the second multi-layers thin film, reflecting wavelength range for. the S-polarization component is changed.
23 Claims, 20 Drawing Sheets
