Eyepiece for near eye display system

• US 9,507,066 B2
• Filed: 06/30/2014
• Issued: 11/29/2016
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Kollin, Joel S., Lanier, Jaron, Burger, Douglas C.
• Primary Examiner(s): Rude, Timothy L
• Application Number:
  US14/320,382
• Publication Number:
  US 20150378074A1
• Time in Patent Office: 883 Days
• US Class Current: 1/1
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 5/3016 involving passive liquid crystal elements optical properties of liquid crystals G02F1/0063; polarising elements associated with active liquid crystal devices G02F1/133528
• CPC Class Codes: G02B 5/3058 comprising electrically conductive elements, e.g. wire grids, conductive particles

Abstract

An optical display system configured to transmit light along a light path to a user'"'"'s eye, the display system comprising a circular polarizing reflector configured to reflect light with a first polarization from an image source, a quarter wave plate downstream of the circular polarizing reflector in the light path and configured to rotate the polarization of the light to a second polarization, and a curved linear polarizing reflector downstream of the quarter wave plate and configured to reflect the light back through the quarter wave plate along the light path in the direction of the circular polarizing reflector. The quarter wave plate further configured to rotate the polarization of the light received from the curved linear polarizing reflector to a third polarization and the circular polarizing reflector further configured to receive said light from the quarter wave plate and transmit the light toward the user'"'"'s eye.

Claims

1. An optical display system configured to transmit light along a light path to a user'"'"'s eye, the display system comprising:

a circular polarizing reflector configured to reflect light with a first polarization originating from an image source;

a quarter wave plate positioned downstream of the circular polarizing reflector in the light path, the quarter wave plate configured to rotate the polarization of the light from the first polarization to a second polarization; and

a curved linear polarizing reflector positioned downstream of the quarter wave plate, the curved linear polarizing reflector configured to reflect the light with the second polarization back through the quarter wave plate along the light path in the direction of the circular polarizing reflector;

wherein the quarter wave plate is further configured to rotate the polarization of the light received from the curved linear polarizing reflector from the second polarization to a third polarization; and

wherein the circular polarizing reflector is further configured to receive the light having the third polarization from the quarter wave plate and to transmit the light with the third polarization toward the user'"'"'s eye.

2. The display system of claim 1, wherein the quarter wave plate is a switchable quarter wave plate configured to rotate the polarization of the light if the switchable quarter wave plate is activated and to not rotate the polarization of the light if the quarter wave plate is deactivated.

3. The display system of claim 1, further comprising:

an initial polarizer positioned upstream of the circular polarizing reflector on the light path, the initial polarizer configured to receive light from the image source and transmit light with an initial polarization along the light path toward the curved linear polarizing reflector;

wherein the curved linear polarizing reflector is further configured to receive the light with the initial polarization from the initial polarizer and transmit the light along the light path toward the quarter wave plate; and

wherein the quarter wave plate is further configured to rotate the polarization of the light received from the curved linear polarizing reflector from the initial polarization to the first polarization and transmit the light along the light path toward the circular polarizing reflector.

4. The display system of claim 1, further comprising:

a fixed wave plate positioned upstream of the circular polarizing reflector on the light path, the fixed wave plate configured to receive the light from the image source and transmit light with the first polarization along the light path in a direction of a prism disposed between the fixed wave plate and the circular polarizing reflector;

wherein the prism is configured to receive the light through a light input side of the prism and reflect the light off an internal surface of the prism via total internal reflection along the light path toward the circular polarizing reflector.

5. The display system of claim 4, wherein the image source is positioned at an angle less than ninety degrees with respect to an optical axis of the curved linear polarizing reflector so as to project side-addressed light toward the curved linear polarizing reflector.

6. The display system of claim 1, wherein the curved linear polarizing reflector is a curved wire grid polarizing beamsplitter.

7. The display system of claim 1, wherein the circular polarizing reflector is a cholesteric liquid crystal reflective polarizer.

8. The display system of claim 1, wherein the circular polarizing reflector is configured to have a flat shape.

9. The display system of claim 1, wherein the circular polarizing reflector is configured to have a curved shape.

10. The display system of claim 1, wherein the image source, curved linear polarizing reflector, quarter wave plate, and circular polarizing reflector of the display system are mounted in a near-eye display device.

11. The display system of claim 10, wherein the near eye display device is incorporated into a housing of a head mounted display device.

12. A method of transmitting light along a light path to a user'"'"'s eye, comprising:

reflecting light originating from an image source having a first polarization off of a circular polarizing reflector along the light path toward a quarter wave plate;

rotating the polarization of the light from the first polarization to a second polarization with the quarter wave plate and transmitting the light with the second polarization along the light path toward a curved linear polarizing reflector;

reflecting the light off of the curved linear polarizing reflector and transmitting the light along the light path back toward the quarter wave plate;

rotating the polarization of the light from a second polarization to a third polarization with the quarter wave plate and transmitting the light along the light path toward the circular polarizing reflector; and

transmitting the light through the circular polarizing reflector along the light path toward the user'"'"'s eye.

13. The method of claim 12, further comprising:

rotating the polarization of the light with the quarter wave plate when the quarter wave plate is in an activated state and not rotating the polarization of the light when the quarter wave plate is in a deactivated state.

14. The method of claim 12, further comprising:

converting the polarization of the light originating from the image source to an initial polarization via an initial polarizer positioned upstream on the light path from the circular polarizing reflector;

transmitting the light from the initial polarizer along the light path toward the curved linear polarizing reflector

transmitting the light through the curved linear polarizing reflector along the light path toward the quarter wave plate;

rotating the polarization of the light from the initial polarization to a first polarization with the quarter wave plate; and

transmitting the light from the quarter wave plate along the light path toward the circular polarizing reflector.

15. The method of claim 12, further comprising:

converting the polarization of the light from the image source to a first polarization via a fixed wave plate positioned upstream of the circular polarizing reflector on the light path;

transmitting the light from the fixed wave plate along the light path toward a prism positioned on the light path between fixed wave plate and the circular polarizing reflector;

reflecting the light via total internal reflection off of an interior surface of the prism; and

transmitting the light along the light path toward the circular polarizing reflector.

16. The method of claim 15, further comprising:

transmitting the light from the image source at an angle less than ninety degrees with respect to an optical axis of the curved polarizing reflector.

17. The method of claim 12, wherein the curved linear polarizing reflector is a curved wire grid polarizing beamsplitter.

18. The method of claim 12, wherein the circular polarizing reflector is a cholesteric liquid crystal reflective polarizer.

19. The display system of claim 12, wherein the circular polarizing reflector is one of a flat or curved shape.

20. A method of transmitting light along a light path to a user'"'"'s eye, comprising:

converting the polarization of light from an image source to a first polarization via a fixed wave plate positioned upstream of a circular polarizing reflector on the light path;

transmitting the light from the fixed wave plate along the light path toward a prism positioned on the light path between fixed wave plate and the circular polarizing reflector;

reflecting the light via total internal reflection off of an interior surface of the prism;

transmitting the light along the light path toward the circular polarizing reflector;

reflecting the light originating from the image source having the first polarization off of a circular polarizing reflector along the light path toward a quarter wave plate;

rotating the polarization of the light from the first polarization to a second polarization with the quarter wave plate and transmitting the light with the second polarization along the light path toward a curved linear polarizing reflector;

reflecting the light off of the curved linear polarizing reflector and transmitting the light along the light path back toward the quarter wave plate;

rotating the polarization of the light from a second polarization to a third polarization with the quarter wave plate and transmitting the light along the light path toward the circular polarizing reflector; and

transmitting the light through the circular polarizing reflector along the light path toward the user'"'"'s eye.