Scattering display for contrast enhancement including target

• US 4,732,456 A
• Filed: 05/18/1987
• Issued: 03/22/1988
• Est. Priority Date: 08/28/1984
• Status: Expired due to Term

• Current Assignee: Raychem Corporation (TE Connectivity Limited)
• Original Assignee: Taliq Corp. (TE Connectivity Limited)
• Inventors: Parker, Robert, Fergason, James L.
• Primary Examiner(s): Miller, Stanley D.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US07/053,583
• Time in Patent Office: 309 Days
• Field of Search: 350/345, 350/355, 350/356, 350/354, 350/104-106, 350/97, 350/342, 350/338, 350/331 R, 350/339 D, 350/339 F, 350/351, 350/357, 350/346
• US Class Current: 349/95
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133526 Lenses, e.g. microlenses or Fresnel lenses
• CPC Class Codes: G02F 1/13756 the liquid crystal selectively assuming a light-scattering state G02F1/1334, G02F1/13718 take precedence

Abstract

A display comprising optical means for presenting an absence of light over a controlled viewing angle and means for selectively scattering or transmitting light in response to a prescribed input to effect a display of information within said viewing angle.

Claims

1. A display comprising means having two states, one state for scattering incident light and a second state for transmitting incident light as a response to a prescribed input independent of the incident light, and focusing means for directing unscattered light transmitted through said scattering or transmitting means onto a light absorbing target means external to and on a non-viewing side of said scattering or transmitting means for enhancing the contrast of the display.

2. The display of claim 1 wherein said scattering or transmitting means comprises a liquid crystal means.

3. The display of claim 2 wherein said liquid crystal means comprises at least one layer of nematic curvilinearly aligned phases liquid crystal material.

4. The display of claim 1 wherein said optical means has a focal point and said target means is located at approximately said focal point.

5. The liquid crystal apparatus of claim 4 wherein said target means comprises a black absorber for absorbing substantially all of the light incident thereon or a colored absorber for absorbing only one or more specified wavelengths of light.

6. A display, comprising:

means selectively operable for affecting light incident thereon and having two states, one state for scattering light and a second state for transmitting light in response to a prescribed input independent of the incident light;

a target means located on a non-viewing side of said selectively operable means for absorbing light incident thereon; and

a lens means disposed between said selectively operable means and said target means for directing light transmitted through said selectively operable means onto said target means to enhance the contrast of the display.

7. The display of claim 6 wherein said selectively operable means comprises a liquid crystal means.

8. The display of claim 7 wherein said liquid crystal means comprises at least one layer of nematic curvilinearly aligned phases liquid crystal material.

9. The display of claims 6, 7 or 8 further including an illumination source on the non-viewing side of the display for directing light toward said lens means.

10. The display of claim 9 wherein said lens means comprises a plurality of cylindrical rods disposed adjacent to one another.

11. The display of claim 10 wherein said target means comprises a stripe extending substantially along the length of each of said cylindrical rods.

12. The display of claim 11 wherein said target means is positioned between the backsurface of said lens means and the focal point thereof.

13. The display of claim 12 wherein said strip comprises a black absorber for absorbing at least substantially all of the light incident thereon or a colored absorber for absorbing only one or more specified wavelengths of light.

14. The display of claim 12 wherein the height of said stripes is approximately equal to one sixth the diameter of said cylindrical rods.

15. The display of claim 12 wherein said selectively operable means is spaced from said cylindrical rods a distance approximately equal to twice the diameter thereof.

16. The display of claims 6, 7 or 8 wherein said lens means comprises a plurality of spheres disposed adjacent to one another.

17. The display of claim 16 wherein said target means comprises a dot located at the backside of each of said spheres.

18. The display of claim 17 wherein said dot is positioned between the backside of said spheres and the focal point thereof.

19. The display of claim 18 wherein the diameter of said spots is approximately equal to one-sixth the diameter of said spheres.

20. The display of claim 18 wherein said dot comprises a black absorber for absorbing at least substantially all of the light incident thereon or a colored absorber for absorbing only one or more specified wavelengths of light.

21. The display of claim 18 wherein said selectively operable means is spaced from said spheres a distance approximately equal to twice the diameter thereof.

22. A method for contrast enhancement, comprising:

scattering or transmitting incident light by means of an electro-optical device as a response to a given electrical input independent of incident light, said electro-optical device having two states, a first state for scattering light and a second state for transmitting light; and

focusing unscattered light transmitted through said electro-optical device onto a light absorbing target means external to and on a non-viewing side of said electro-optical device for enhancing contrast.

23. A display, comprising:

liquid crystal means operable for affecting light incident thereon and having two states, one state for scattering light and a second state for transmitting light in response to a prescribed input independent of the incident light;

a target means located on a non-viewing side of said liquid crystal means for absorbing light incident thereon; and

a plurality of cylindrical lenses disposed between said liquid crystal means and said target means for directing light transmitted through said liquid crystal means onto said target means to enhance the contrast of the display.

24. The display of claim 23 wherein said lenses comprise cylindrical rods.