United States Patent [19] [n] Patent Number: 4,630,895
Abdala, Jr. et al. [45] Date of Patent: Dec. 23, 1986
[54] LCD LIGHTGUIDE
[75] Inventors: Julio Abdala, Jr., Miami; Bernard V.
Gasparaitis, Tamarac, both of Fla.
[73] Assignee: Motorola, Inc., Schaumburg, 111.
[21] Appl. No.: 741,912
[22] Filed: Jun. 6, 1985
[51] Int. CI." G02F 1/13
[52] U.S. CI 350/345; 362/31;
362/104; 362/297
[58] Field of Search 350/345; 362/31, 26,
362/27, 297, 298, 301, 104
[56] References Cited
U.S. PATENT DOCUMENTS
2,131,471 9/1938 Carter 362/31
2,341,658 2/1944 Salani 362/297
2,712,593 7/1955 Merchant 362/27
2,965,749 12/1960 Hudson 362/27
3,561,145 2/1971 Shotwell 362/26 X
3,740,540 6/1973 Takeichi et al 362/27
4,059,916 11/1977 Tachihara et al 350/345 X
4,258,643 3/1981 Ishikawa et al 362/26 X
4,277,817 7/1981 Hehr 350/345 X
4,486,077 12/1984 Torresdal 362/31
Primary Examiner—L. T. Hix
Assistant Examiner—Brian W. Brown
Attorney, Agent, or Firm—Martin J. McKinley; Joseph
T. Downey; Donald B. Southard
[57] ABSTRACT
A backlighted display system includes a liquid crystal display, a flat light guide behind the display, and light emitting diodes (LED's). The light guide is a molded slab of clear polycarbonate material with two planes depressed into its rear surface. Four segmented bordering surfaces are approximately arcuate in shape. The depressed planes, the segmented bordering surfaces, and the rear surface are coated with a reflective white paint. LED holders are integrally molded with the light guide. A central portion of the front surface is optionally textured. The display system provides thin construction with even light distribution across the width of the display, low power consumption, and good outdoor visibility at dusk or dawn.
18 Claims, 7 Drawing Figures
