REFLECTIVE LIQUID CRYSTAL ON SILICON PANEL

• US 20070242195A1
• Filed: 04/17/2006
• Published: 10/18/2007
• Est. Priority Date: 04/17/2006
• Status: Abandoned Application

• Current Assignee: United Microdisplay Optronics Corporation (United Microelectronics Corporation)
• Original Assignee: United Microdisplay Optronics Corporation (United Microelectronics Corporation)
• Inventors: Whitehead, Tony, Kuan, Da-Shuang, Meng, Chi-Tai
• Application Number:
  US11/308,640
• Publication Number:
  US 20070242195A1
• Time in Patent Office: Days
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133548 Wire-grid polarisers
• CPC Class Codes: G02F 1/133565 inside the LC elements, i.e. between the cell substrates
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/136277 formed on a semiconductor substrate, e.g. of silicon

Abstract

A reflective liquid crystal on silicon panel (reflective LCOS panel) for polarizing a light beam and converting the light beam into an image is provided. The reflective LCOS panel includes a silicon substrate, an opposite substrate, a liquid crystal layer and a polarizer. The silicon substrate has a pixel array thereon. The opposite substrate is disposed over the silicon substrate and has a transparent electrode thereon. The liquid crystal layer fills up the space between the pixel array of the silicon substrate and the transparent electrode of the opposite substrate. The polarizer is set up on the silicon substrate or the opposite substrate. As described above, the integration of the polarizer with the reflective LCOS panel inside a projection apparatus can effectively reduce the cost, volume and weight of the projection apparatus.

Claims

1. A reflective liquid crystal on silicon (LCOS) panel suitable for polarizing a light beam and converting the polarized light beam into an image, the reflective LCOS panel comprising:

a silicon substrate having a pixel array thereon;

an opposite substrate disposed above the silicon substrate, wherein the opposite substrate has a transparent electrode layer;

a liquid crystal layer disposed between the pixel array of the silicon substrate and the transparent electrode layer of the opposite substrate; and

a polarizer disposed on the silicon substrate or the opposite substrate.

2. The reflective LCOS panel of claim 1, wherein the pixel array further comprises:

a plurality of active devices; and

a plurality of pixel electrodes electrically connected to the respective active devices.

3. The reflective LCOS panel of claim 2, wherein the pixel electrodes are reflective electrodes.

4. The reflective LCOS panel of claim 1, wherein the silicon substrate further comprises:

an absorption layer disposed on the pixel array; and

a color mirror disposed on the absorption layer, wherein at least a portion of the light beam having a wavelength within a specified range is reflected by the color mirror and the remaining portion of the light beam not reflected by the color mirror is absorbed by the absorption layer.

5. The reflective LCOS panel of claim 1, further comprising a retarder disposed between the silicon substrate and the liquid crystal layer.

6. The reflective LCOS panel of claim 1, wherein the pre-tilt angle of the liquid crystal layer is substantially equal to the incident angle of the light beam.

7. The reflective LCOS panel of claim 1, wherein the polarizer is a wire grid.

8. The reflective LCOS panel of claim 7, wherein the wire grid further comprises a plurality of parallel and equidistant conductive lines, each conductive line has a line width between 0.02 micrometer to 1.5 micrometer and the pitch of the conductive lines is between 0.02 micrometer to 2 micrometer.

9. The reflective LCOS panel of claim 7, wherein the opposite substrate is a rectangular substrate and an extending direction of the conductive lines and a side of the opposite substrate form an included angle of 45°

.

10. The reflective LCOS panel of claim 1, wherein the polarizer is disposed on the opposite substrate such that the polarizer and the liquid crystal layer are located on the respective sides of the opposite substrate.

11. The reflective LCOS panel of claim 1, wherein polarizer is disposed on the opposite substrate and located between the liquid crystal layer and the opposite substrate.

12. The reflective LCOS panel of claim 1, wherein the polarizer is disposed on the silicon substrate and located between the liquid crystal layer and the silicon substrate.

13. The reflective LCOS panel of claim 1, further comprising:

a first alignment film disposed on the pixel array of the silicon substrate; and

a second alignment film disposed on the transparent electrode of the opposite substrate, wherein liquid crystal molecules of the liquid crystal layer are oriented through the first alignment film and the second alignment film.

14. The reflective LCOS panel of claim 1, further comprising a protective layer disposed on the opposite substrate to cover the polarizer.