Electrically tunable polarization independent liquid crystal micro-lens array comprising top and bottom liquid crystal layers

• US 10,295,850 B1
• Filed: 06/15/2018
• Issued: 05/21/2019
• Est. Priority Date: 11/13/2017
• Status: Active Grant

• Current Assignee: Black Sesame Technologies, Inc.
• Original Assignee: Black Sesame International Holdings Limited
• Inventors: Xin, Zhaowei, Wei, Dong
• Primary Examiner(s): Lee, Paul C
• Application Number:
  US16/010,135
• Publication Number:
  US 20190146305A1
• Time in Patent Office: 340 Days
• CPC Class Codes: G02B 6/0056 for producing polarisation effects, e.g. by a surface with polarizing properties or by an additional polarizing elements
• CPC Class Codes: G02F 1/116 using an optically anisotropic medium, wherein the incident and the diffracted light waves have different polarizations, e.g. acousto-optic tunable filter [AOTF] G02F1/125 takes precedence
• CPC Class Codes: G02F 1/29 for the control of the position or the direction of light beams, i.e. deflection
• CPC Class Codes: G02F 2201/122 having a particular pattern
• CPC Class Codes: G02F 2201/16 series; tandem
• CPC Class Codes: G02F 2203/06 Polarisation independent

Abstract

A polarization-independent liquid crystal micro-lens array, comprising, an optically transparent, dielectric planar panel, an optically transparent upper planar electrode deposited upon the planar panel top surface and bottom surface, a top substrate positioned adjacent to the planar panel top surface, a top pattern electrode deposited on the top substrate internal surface, a top liquid crystal layer disposed between the planar panel top surface and the top substrate internal surface, the top liquid crystal layer having a first polarization, a bottom substrate positioned adjacent to the planar panel bottom surface, a bottom pattern electrode deposited on the bottom substrate internal surface, a bottom liquid crystal layer disposed between the planar panel bottom surface and the bottom substrate internal surface, the bottom liquid crystal layer having a second polarization orthogonal to the first polarization.

Claims

1. A polarization-independent liquid crystal micro-lens array, comprising:

an optically transparent, dielectric planar panel, the planar panel having a top surface and a bottom surface;

an optically transparent upper planar electrode deposited upon the planar panel top surface;

an optically transparent lower planar electrode deposited upon the planar panel bottom surface;

a top substrate having a top substrate external surface and a top substrate internal surface, the top substrate positioned adjacent to the planar panel top surface;

a top pattern electrode deposited on the top substrate internal surface, wherein the top pattern electrode is patterned with an array of micro-holes;

a top spacer disposed between the planar panel top surface and the top substrate internal surface;

a top liquid crystal layer disposed between the planar panel top surface and the top substrate internal surface, the top liquid crystal layer having a first polarization;

a bottom substrate having a bottom substrate external surface and a bottom substrate internal surface, the bottom substrate positioned adjacent to the planar panel bottom surface;

a bottom pattern electrode deposited on the bottom substrate internal surface, wherein the bottom pattern electrode is patterned with another array of micro-holes;

a bottom spacer disposed between the planar panel bottom surface and the bottom substrate internal surface; and

a bottom liquid crystal layer disposed between the planar panel bottom surface and the bottom substrate internal surface, the bottom liquid crystal layer having a second polarization orthogonal to the first polarization.

2. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the top substrate is silica.

3. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the bottom substrate is silica.

4. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the top pattern electrode may be aluminum.

5. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the bottom pattern electrode may be aluminum.

6. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the upper planar electrode is indium tin oxide.

7. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the lower planar electrode is indium tin oxide.

8. The polarization-independent liquid crystal micro-lens array of claim 1 further comprising a micro-lens connected to the top substrate external surface.

9. The polarization-independent liquid crystal micro-lens array of claim 1 further comprising an image sensor positioned adjacent to the bottom substrate external surface.

10. The polarization-independent liquid crystal micro-lens array of claim 1 wherein the top pattern electrode is patterned having a micro-hole diameter of 128 microns and a pixel-pitch of 160 microns.

11. The polarization-independent liquid crystal micro-lens array of claim 10 wherein the bottom pattern electrode matches the top pattern electrode.

12. A polarization-independent liquid crystal micro-lens array optical system, comprising:

a liquid crystal micro-lens, having;

an optically transparent, dielectric planar panel, the planar panel having a top surface and a bottom surface;

an optically transparent upper planar electrode deposited upon the planar panel top surface;

an optically transparent lower planar electrode deposited upon the planar panel bottom surface;

a top substrate having a top substrate external surface and a top substrate internal surface, the top substrate positioned adjacent to the planar panel top surface;

a top pattern electrode deposited on the top substrate internal surface, wherein the top pattern electrode is patterned with an array of micro-holes;

a top spacer disposed between the planar panel top surface and the top substrate internal surface;

a top liquid crystal layer disposed between the planar panel top surface and the top substrate internal surface, the top liquid crystal layer having a first polarization;

a bottom substrate having a bottom substrate external surface and a bottom substrate internal surface, the bottom substrate positioned adjacent to the planar panel bottom surface;

a bottom pattern electrode deposited on the bottom substrate internal surface, wherein the top pattern electrode is patterned with another array of micro-holes;

a bottom spacer disposed between the planar panel bottom surface and the bottom substrate internal surface;

a bottom liquid crystal layer disposed between the planar panel bottom surface and the bottom substrate internal surface, the bottom liquid crystal layer having a second polarization orthogonal to the first polarization;

a top voltage driver electrically connected to the upper planar electrode and the top pattern electrode; and

a bottom voltage driver electrically connected to the lower planar electrode and the bottom pattern electrode, wherein the bottom voltage driver and top voltage driver are simultaneously actuated to permit transit of unpolarized light through the liquid crystal micro-lens.

13. The polarization-independent liquid crystal micro-lens array optical system of claim 12 further comprising a micro-lens connected to the top substrate external surface.

14. The polarization-independent liquid crystal micro-lens array optical system of claim 13 further comprising an image sensor positioned adjacent to the bottom substrate external surface.

15. The polarization-independent liquid crystal micro-lens array optical system of claim 14 further comprising a main lens positioned adjacent to the micro-lens.

16. The polarization-independent liquid crystal micro-lens array optical system of claim 15 further comprising a housing enclosing the main lens, the micro-lens, the liquid crystal micro-lens and the image sensor.

17. The polarization-independent liquid crystal micro-lens array optical system of claim 12 wherein the top substrate and the bottom substrate are silica.

18. The polarization-independent liquid crystal micro-lens array optical system of claim 12 wherein the top pattern electrode and the bottom pattern electrode are aluminum with a pattern having a micro-hole diameter of 128 microns and a pixel-pitch of 160 microns.

19. The polarization-independent liquid crystal micro-lens array optical system of claim 12 wherein the upper planar electrode and the bottom electrode are indium tin oxide.

20. The polarization-independent liquid crystal micro-lens array optical system of claim 12 wherein the top pattern electrode and the bottom pattern electrode patterns are vertically aligned.