Projection type color liquid crystal optical apparatus

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United States Patent [i9]

Ooi et al.

US005648860A [li] Patent Number: [45] Date of Patent:

5,648,860 Jul. 15, 1997

[54] PROJECTION TYPE COLOR LIQUID CRYSTAL OPTICAL APPARATUS

[75] Inventors: Yoshiharu Ooi; Tsuneo Wakabayashi, Shigeyuki Serizawa; Yoshiyuki Sonda; Masaya Kunigita; Yoshinori Hirai, all

of Yokohama, Japan

[73] Assignee: AG Technology Co., Ltd., Yokohama, Japan

[21] Appl. No.: 198,275
[22] Filed: Feb. 18,1994

Related U.S. Application Data

[63] Continuation-in-part of Ser. No. 133,222, Oct 7, 1993.

[30] Foreign Application Priority Data

Oct. 9, 1992 [JP] Japan 4-298019

Oct. 9, 1992 [JP] Japan 4-298020

Feb. 18, 1993 [JP] Japan 5-52920

Apr. 14, 1993 [JP] Japan 5-111043

[51] Int CI.6 G02F 1/1335; H04N 9/31

[52] U.S. CI 349/10; 353/34; 353/31;

349/67; 349/114; 349/139

[58] Field of Search 359/40, 87, 41,

359/70, 51, 71, 52, 48, 49; 353/31, 102, 34, 122, 33, 37; 348/751, 756, 757

[56] References Cited

U.S. PATENT DOCUMENTS

4,613,207 9/1986 Fergason 359/51

4,818,070 4/1989 Gunjima et al 359/93

4,834,509 5/1989 Gunjima et al 359/52

5,103,327 4/1992 Hirai et al 359/91

5,162,934 11/1992 Gunjima et al 359/51

5,196,952 3/1993 Hirai et al 359/51

5,216,531 6/1993 Hirai et al 359/52

5,235,445 8/1993 Hirai et al 359/52

5,379,083 1/1995 Tomita 353/122

5,379,135 1/1995 NakagaM et al 359/40

5,398,081 3/1995 Jones 359/40

A light source optical system for projection 1, dichroic mirrors 21, 22 disposed to have a predetermined included angle p, a reflection type liquid crystal optical element blocks 31-33 each including a closely contacted converging lens and having a reflection surface and a projection optical system 4 are provided, wherein the normal line of a dichroic mirror surface and the optical axis of incident light form an included angle a; the normal line of the reflection surface and the optical axis of incident light form an included angle y; light emitted from a light source is color-separated so as to become color lights; the color lights are rendered to be parallel light beams, and are modulated and reflected by means of the reflection type liquid crystal optical elements; the reflected light beams are color-synthesized; and the color-synthesized light is projected through a projection lens. A projection type color liquid crystal optical apparatus having a compact shape and a high brightness is obtainable.

13 Claims, 14 Drawing Sheets

OTHER PUBLICATIONS

1989 Autumn Meeting of Electronics, Information and Communication Academy, "Reflective Type High Density TFT Array For High Definition Liquid Crystal Projection TV", pp. 5-30.

Liquid Crystals Applications and Uses, vol. 1, 1990, S.E. Shields, et al., "Light Valve Projection Mode LCDs", pp. 455^67, 488-489.

SPIE vol. 1255 Large-Screen Projection Displays H (1990), R. Gerhard-Multhaupt, et al., "Viscoelastic Spatial Light Modulators and Schlieren-Optical Systems For HDTV Projection Displays", pp. 69-78.

Patent Abstracts of Japan, vol. 16, No. 421 (P-1414), Sep. 4, 1992, JP-A-04 142 528, May 15, 1992.