SWITCHABLE GRATING BASED ON ELECTROPHORETIC PARTICLE SYSTEM

• US 20100134872A1
• Filed: 11/06/2007
• Published: 06/03/2010
• Est. Priority Date: 11/21/2006
• Status: Abandoned Application

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Bsesjou, Patrick John, Johnson, Mark Thomas, Roosendaal, Sander Jurgen, De Boer, Dirk Kornelis Gerhardus
• Application Number:
  US12/515,292
• Publication Number:
  US 20100134872A1
• Time in Patent Office: Days
• US Class Current: 359/296
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 2201/305 diffraction grating
• CPC Class Codes: G02F 2203/06 Polarisation independent
• CPC Class Codes: G02F 2203/22 diffractive

Abstract

A switchable optical component (10) includes a substrate (18) forming a cavity (14). The substrate (18) is configured with a structured surface (24, 26) adjacent to the cavity, and the substrate has a first index of refraction. A fluid (16) contacts the structured surface. Particles (12) are selectively dispersible in the fluid such that a first concentration of particles in the fluid enables the structured surface to provide an optical effect, and a second concentration of particles in the fluid disables the optical effect.

Claims

1. A switchable optical component, comprising:

a substrate (18) forming a cavity (14), the substrate being configured with a structured surface (24, 26) adjacent to the cavity and the substrate having a first index of refraction;

a fluid (16) in contact with the structured surface; and

particles (12) selectively dispersible in the fluid such that a first concentration of particles in the fluid enables the structured surface to provide an optical effect and a second concentration of particles in the fluid disables the optical effect.

2. The component as recited in claim 1, wherein the particles (12) include electrophoretic particles and the particles are dispersible based on voltage changes in proximity of the fluid.

3. The component as recited in claim 2, further comprising a plurality of electrodes (20, 22) disposed adjacent to the cavity wherein the particles are dispersed in the fluid by altering the voltages on the electrodes.

4. The component as recited in claim 3, wherein the electrodes (20, 22) are disposed on a same side of the cavity.

5. The component as recited in claim 3, wherein the electrodes (102, 104) are disposed on opposite sides of the cavity.

6. The component as recited in claim 1, where, in one of the first concentration and the second concentration, a uniform layer (105) of particles are formed in the cavity opposite the structured surface.

7. The component as recited in claim 1, where, in one of the first concentration and the second concentration, the particles (12) are laterally collected outside of an area of the structured surface.

8. The component as recited in claim 1, where, in one of the first concentration and the second concentrations, the particles (12) are collected in portions of the structured surface.

9. The component as recited in claim 1, wherein the structured surface includes a grating profile (24, 26).

10. The component as recited in claim 9, wherein the incident light is non-polarized and the grating profile provides diffraction of the incident light.

11. A switchable diffraction grating, comprising:

a substrate (18) forming a cavity (14), the substrate being configured with a diffraction grating profile (24, 26) adjacent to the cavity and the substrate having a first index of refraction;

a fluid (16) in contact with the grating profile;

electrophoretic particles (12) selectively dispersible in the fluid such that a first concentration of particles in the fluid enables the grating profile to provide an optical effect and a second concentration of particles in the fluid disables the optical effect; and

a plurality of electrodes (20, 22, or 102, 104) disposed adjacent to the cavity wherein the particles are dispersed in the fluid by altering voltages on the electrodes.

12. The grating as recited in claim 11, wherein the electrodes (20, 22) are disposed on a same side of the cavity.

13. The grating as recited in claim 11, wherein the electrodes (102, 104) arc disposed on opposite sides of the cavity.

14. The grating as recited in claim 11, wherein, in one of the first and second concentrations of particles, the particles form a uniform layer (105) in the cavity opposite the grating profile.

15. The grating as recited in claim 11, wherein, in one of the first and second concentrations of particles, the particles (12) are laterally collected outside of an area of the grating profile.

16. The grating as recited in claim 11, wherein, in one of the first and second concentrations of particles, the particles (12) are collected in portions of the grating profile.

17. The grating as recited in claim 11, wherein the grating profile is included in an array of gratings.

18. The grating as recited in claim 11, wherein the grating profile is included in a stack of gratings.

19. The grating as recited in claim 11, wherein incident light is non-polarized and the grating profile provides diffraction of the incident light.

20. A method for operating a switchable optical component, comprising:

providing (402) an in-plane electrophoretic device having a substrate forming a cavity where the substrate is configured with a grating profile adjacent to the cavity and the substrate has a first index of refraction;

contacting (406) the grating profile with a fluid; and

selectively dispersing particles (410) in the fluid such that a first concentration of particles in the fluid enables the grating profile to provide an optical effect and a second concentration of particles disables the optical effect.

21. The method as recited in claim 20, wherein the particles include electrophoretic particles and selectively dispersing the particles (410) includes selectively dispersing the particles (412) based on voltage changes in proximity of the fluid.

22. The method as recited in claim 21, wherein the voltage changes are implemented using electrodes disposed adjacent to the cavity wherein the particles are dispersed in the fluid by altering the voltages on the electrodes.

23. The method as recited in claim 22, wherein the electrodes are disposed on a same side of the cavity.

24. The method as recited in claim 22, wherein the electrodes are disposed on opposite sides of the cavity.

25. The method as recited in claim 20, wherein selectively dispersing particles (410) includes forming a uniform layer (105) of particles in the cavity opposite the grating profile.

26. The method as recited in claim 20, wherein selectively dispersing particles (410) includes collecting the particles laterally outside of an area of the grating profile.

27. The method as recited in claim 20, wherein selectively dispersing particles (410) includes collecting the particles in portions of the grating profile.

28. The method as recited in claim 20, wherein incident light is non-polarized and the method includes diffracting the non-polarized incident light using the grating profile.