Optical modulation system

• US 7,876,400 B2
• Filed: 10/31/2005
• Issued: 01/25/2011
• Est. Priority Date: 10/31/2005
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Emmerich, Timothy D., Devos, John A., Baliga, Roshan B., Howard, P. Guy, Fricke, Peter J., Aufranc, Richard
• Primary Examiner(s): Nelms; David
• Assistant Examiner(s): Briggs; Nathanael R
• Application Number:
  US11/263,523
• Publication Number:
  US 20070097478A1
• Time in Patent Office: 1,912 Days
• Field of Search: 349/74, 349/86, 349/73, 349/33
• US Class Current: 349/74
• CPC Class Codes: G02F 1/13318 Circuits comprising a photodetector
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/1347 Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells
• CPC Class Codes: G03B 21/56 Projection screens

Abstract

Embodiments including a charge responsive optical material are disclosed.

Claims

1. An apparatus comprising:

a first conductor;

a second conductor;

a third conductor;

a first charge responsive optical material between the first conductor and the second conductor;

a second charge responsive optical material between the second conductor and the third conductor; and

a controller configured to generate control signals, wherein a first alternating current having a first alternating charge is applied to the first conductor and a second alternating current having a second alternating charge out of phase with the first alternating current is applied to the second conductor in response to the control signals.

2. The apparatus of claim 1, wherein the first conductor and the third conductor are transparent.

3. The apparatus of claim 1, wherein the first charge responsive optical material has a thickness of less than or equal to about 5 microns.

4. The apparatus of claim 1, wherein the first charge responsive optical material has a thickness of at least about 2 microns.

5. The apparatus of claim 1, wherein the first charge responsive optical material comprises a polymer dispersed liquid crystal.

6. The apparatus of claim 1, further comprising an opaque layer opposite the second charge responsive optical material.

7. The apparatus of claim 6 wherein the opaque layer is configured to absorb substantially all visible light.

8. The apparatus of claim 6, wherein the opaque layer is configured to substantially reflect all visible light.

9. The apparatus of claim 1 further comprising:

a first unit comprising;

the first conductor;

the second conductor;

the third conductor;

the first charge responsive optical material; and

the second charge responsive optical material; and

a second unit releasably and physically connected to the first unit along adjacent opposite edges of the first unit and the second unit, the second unit comprising;

a fourth conductor electrically connected to the first conductor;

a fifth conductor electrically connected to the second conductor;

a sixth conductor electrically connected to the third conductor;

a third charge responsive optical material between the fourth conductor and the fifth conductor; and

a fourth charge responsive optical material between the fifth conductor and the sixth conductor.

10. The apparatus of claim 9 further comprising a third unit releasably connected to the second unit along adjacent opposite edges of the second unit and the third unit, the third unit comprising:

a seventh conductor electrically connected to the conductor;

a eighth conductor electrically connected to the second conductor;

a ninth conductor electrically connected to the third conductor;

a fifth charge responsive optical material between the seventh conductor and the eight conductor; and

a sixth charge responsive optical material between the eighth conductor and the ninth conductor.

11. The apparatus of claim 9 wherein the first unit and the second unit are electrically connected to one another along adjacent opposite edges.

12. The apparatus of claim 9 further comprising a controller configured to generate control signals, wherein the first unit and the second unit modulate light substantially similarly in response to the control signals.

13. The apparatus of claim 9 further comprising a controller configured to generate control signals, wherein the first unit and the second unit modulate light substantially differently in response to the control signals.

14. The apparatus of claim 9 wherein the first unit has a first edge and a second opposite edge and wherein the first unit is configured to modulate light similarly across the first unit from the first edge to the second edge.

15. The apparatus of claim 1 wherein a phase relationship of the first alternating current and the second alternating current is varied in response to the control signals.

16. The apparatus of claim 1, wherein the controller is configured to generate control signals such that the first alternating current having the first alternating charge applied to the first conductor and the second alternating current having the second alternating charge applied to the second conductor are substantially 180 degrees out of phase with respect to one another.

27. The apparatus of claim 1, wherein the first alternating current comprise a first waveform and the second alternating current comprises a second waveform.

28. The apparatus of claim 1, wherein the first alternating current comprises a first sinusoidal waveform and the second alternating current comprises a second sinusoidal waveform.

29. The apparatus of claim 1, wherein the first alternating current and the second alternating current are out of phase greater than 0 degrees and less than 180 degrees.

17. An apparatus comprising:

a first conductor;

a second conductor;

a third conductor;

a first charge responsive optical material between the first conductor and the second conductor;

a second charge responsive optical material between the second conductor and the third conductor; and

a controller configured to generate control signals, wherein a first alternating current having a first alternating charge is applied to the first conductor and a second alternating current having a second alternating charge out of phase with the first alternating current is applied to the second conductor in response to the control signals and wherein a phase relationship of the first alternating current and the second alternating current is varied in response to the control signals.

30. The apparatus of claim 17, wherein the first alternating current and the second alternating current are out of phase greater than 0 degrees and less than 180 degrees.

18. An apparatus comprising:

a first unit comprising;

a first conductor;

a second conductor;

a third conductor;

a first charge responsive optical material between the first conductor and the second conductor;

a second charge responsive optical material between the second conductor and the third conductor; and

a second unit releasably and physically connected to the first unit along adjacent opposite edges of the first unit and the second unit, the second unit comprising;

a fourth conductor electrically connected to the first conductor;

a fifth conductor electrically connected to the second conductor;

a sixth conductor electrically connected to the third conductor;

a third charge responsive optical material between the fourth conductor and the fifth conductor; and

a fourth charge responsive optical material between the fifth conductor and the sixth conductor, wherein the first unit and the second unit each include two adjacent sides having male electrical connectors and two adjacent sides having female electrical connectors.

19. The apparatus of claim 18 further comprising a third unit releasably connected to the second unit along adjacent opposite edges of the second unit and the third unit, the third unit comprising:

a seventh conductor electrically connected to the first conductor;

a eighth conductor electrically connected to the second conductor;

a ninth conductor electrically connected to the third conductor;

a fifth charge responsive optical material between the seventh conductor and the eight conductor; and

a sixth charge responsive optical material between the eighth conductor and the ninth conductor.

20. The apparatus of claim 18 wherein the first unit and the second unit are electrically connected to one another along adjacent opposite edges.

21. The apparatus of claim 18 further comprising a controller configured to generate control signals, wherein the first unit and the second unit modulate light substantially similarly in response to the control signals.

22. The apparatus of claim 18 further comprising a controller configured to generate control signals, wherein the first unit and the second unit modulate light substantially differently in response to the control signals.

23. The apparatus of claim 18 wherein the first unit has a first edge and a second opposite edge and wherein the first unit is configured to modulate light similarly across the first unit from the first edge to the second edge.

24. The apparatus of claim 18, wherein the second unit may be removed from the first unit to reduce a dimension of the apparatus and wherein the first unit is operable when disconnected from the second unit.

25. The apparatus of claim 18, wherein the first charge responsive optical material, the second charge responsive optical material, the third charge responsive optical material and the fourth charge responsive optical material all change between first identical light interacting states and second identical light interacting states.

26. The apparatus of claim 18, wherein the first charge responsive optical material and the third charge responsive optical material are each configured to change between a first substantially white state in which visible light is reflected and diffused and a substantially clear state.