Saturation drive arrangements for optically bistable displays

• US 3,982,239 A
• Filed: 07/22/1974
• Issued: 09/21/1976
• Est. Priority Date: 02/07/1973
• Status: Expired due to Term

• Current Assignee: Solomon Sheer
• Original Assignee: North Hills Electronics, Inc. (Transdigm Group Incorporated)
• Inventors: Sherr, Solomon
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US05/490,556
• Time in Patent Office: 792 Days
• Field of Search: 340/324 R, 340/324 M, 340/336, 340/166 EL, 350/160 LC
• US Class Current: 345/45
• CPC Class Codes: G04G 9/062 using multiplexing techniques
• CPC Class Codes: G04G 9/122 using multiplexing techniques
• CPC Class Codes: G09G 2300/023 Display panel composed of stacked panels
• CPC Class Codes: G09G 3/18 using liquid crystals
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

An addressed display system using material, such as liquid crystal, light emitting diodes, ferroelectrics, fluid flow devices, electroluminiscent materials, etc., which exhibit at least two characteristic modes of operation in accordance with the electric field applied. The materials are assembled with appropriately disposed conductors for establishing the electric field in discrete areas. These conductors are selectively addressed to effect a substantially zero potential at the discrete areas being chosen and at least a saturation potential across all other areas. The display embodiments include matrices, alphanumerics, and a chronometer.

Claims

1. A display assembly using material which exhibits at least two characteristic modes of operation in accordance with the electric field applied, the first being a quiescent state at substantially zero potential and the second being assumed in response to a voltage of at least a predetermined magnitude, comprising:

the assemblage of said material in substantially planar form with spaced conductive means on opposing faces thereof to define a plurality of discrete areas, each of the conductive means on one side of said material embracing a first plurality of discrete areas, each of the conductive means on the other side of said material embracing a second plurality of said discrete areas, and each one of said second plurality of areas appearing within a different one of said first plurality of areas; and

control means operative to establish a substantially zero potential between the conductive means of preselected discrete areas, to establish a potential of a first polarity and at least said predetermined magnitude on the remaining conductive means of said first plurality, and to establish a potential of the opposite polarity and at least said predetermined magnitude on the remaining conductive means of said second plurality.

2. A display assembly according to claim 1, wherein said material is liquid crystal material.

3. A display assembly according to claim 1, wherein said material is ferroelectric material.

4. A display assembly according to claim 1, wherein said material is electroluminescent material.

5. A display assembly according to claim 1, wherein alternating voltages are applied on each of said conductive means.

6. A display assembly according to claim 5, wherein the phase of said voltages on said conductive means is controlled to effect the desired polarity conditions.

7. A display assembly according to claim 1, wherein said voltages are in pulse form.

8. A display assembly according to claim 1, wherein said conductive means are circumferentially arranged on opposite sides of said material, each of the conductive means on one side of said material embraces a first plurality of adjacent discrete areas and each of the conductive means on the other side of said material embraces a second plurality of said areas, each one of said second plurality of areas appearing within a different one of said first plurality of areas.

9. A display assembly according to claim 8, wherein said control means effects establishment of said substantially zero potential across a different pair of conductive means for successive adjacent discrete portions of said material at a periodic rate.

10. A display assembly according to claim 8, wherein said material is liquid crystal material.

11. A display assembly according to claim 8, wherein said material is ferroelectric material.

12. A display assembly according to claim 8, wherein said material is electroluminescent material.

13. A display assembly according to claim 1, wherein said material is nematic liquid crystal material that is light transmissive in its quiescent state and light scattering when a potential of at least said predetermined magnitude is applied.

14. A display assembly according to claim 1, wherein said material is a liquid crystal material, and including an analyzer-polarizer combination disposed on opposite sides of said assembly.

15. A display assembly according to claim 1, wherein said material is liquid crystal material and said conductive means include transparent conductor films deposited on transparent substrates positioned on opposite sides of said material.

16. A display assembly according to claim 1, wherein said material is arranged as a planar panel of liquid crystal material provided with said conductive means on the opposing faces;

the conductive means on one face substantially covering the entire surface;

a first plurality of conductive means on the opposing face, each being configured and positioned to represent a segment of the alphanumeric characters in a particular font.

17. A display assembly according to claim 16, wherein alternating voltages are applied on each of said conductive means.

18. A display assembly according to claim 17, wherein the phase of said voltages on said conductive means is controlled to effect the desired polarity conditions.

19. A display assembly according to claim 16, wherein said voltages are in pulse form.