Head-mounted projection display using reflective microdisplays

Patent metadata

Field	Value
Publication number	US-9310591-B2
Application number	US-201313955076-A
Country	US
Kind code	B2
Filing date	Jul 31, 2013
Priority date	Jan 22, 2008
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

The present invention relates generally to a head-mounted projection display, and more particularly, but not exclusively to a polarized head-mounted projection display including a light engine and a compact, high-performance projection lens for use with reflective microdisplays.

First claim

What is claimed is:

1. A compact, telecentric projection lens for use in a head-mounted projection display system, comprising a plurality of lens elements configured to have an overall length that is no more than about two times the effective focal length of the projection lens and configured so that the projection lens is telecentric in image space, wherein the back focal length is about 40% larger than the effective focal length of the projection lens.

2. The compact, telecentric projection lens according to claim 1 , wherein the overall length is no more than about 85% larger than the effective focal length of the projection lens.

3. The compact, telecentric projection lens according to claim 1 , wherein the projection lens comprises a diffractive optical element.

4. The compact, telecentric projection lens according to claim 1 , wherein the plurality of lens elements includes a final lens element closest to the image plane, the final lens element including a diffractive optical element disposed thereon.

5. The compact, telecentric projection lens according to claim 4 , wherein the final lens element includes an aspheric surface.

6. The compact, telecentric projection lens according to claim 5 , wherein the diffractive optical element is disposed on the aspheric surface.

7. The compact, telecentric projection lens according to claim 1 , wherein at least two-thirds of the lens elements comprise plastic.

8. A compact, telecentric projection lens for use in a head-mounted projection display system, comprising a plurality of lens elements configured to have an overall length that is no more than about two times the effective focal length of the projection lens and configured so that the projection lens is telecentric in image space, wherein the projection lens comprises a lens group disposed on the object side of the stop of the projection lens, the lens group having an effective focal length of at least two orders of magnitude larger than the effective focal length of the projection lens.

9. The compact, telecentric projection lens according to claim 8 , wherein the overall length is no more than about 85% larger than the effective focal length of the projection lens.

10. The compact, telecentric projection lens according to claim 8 , wherein the projection lens comprises a diffractive optical element.

11. The compact, telecentric projection lens according to claim 8 , wherein the plurality of lens elements includes a final lens element closest to the image plane, the final lens element including a diffractive optical element disposed thereon.

12. The compact, telecentric projection lens according to claim 11 , wherein the final lens element includes an aspheric surface.

13. The compact, telecentric projection lens according to claim 12 , wherein the diffractive optical element is disposed on the aspheric surface.

14. The compact, telecentric projection lens according to claim 8 , wherein at least two-thirds of the lens elements comprise plastic.

Assignees

• Univ Arizona State

Inventors

• Hua Hong
• Zhang Rui

Classifications

• G02B27/286

  for controlling or changing the state of polarisation, e.g. transforming one polarisation state into another (G02B5/3083 takes precedence; light guide coupling means utilising polarising elements G02B6/34) · CPC title

• G02B5/3083

  Birefringent or phase retarding elements (G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001) · CPC title

• G02B2027/0123

  comprising devices increasing the field of view · CPC title

• G02B9/34

  having four components only · CPC title

• G02B5/30

  Polarising elements (light-modulating devices with active elements G02F1/00) · CPC title