Optical apparatus and method

• US 8,194,325 B2
• Filed: 06/30/2009
• Issued: 06/05/2012
• Est. Priority Date: 06/30/2009
• Status: Active Grant

• Current Assignee: Magic Leap, Inc.
• Original Assignee: Nokia Corporation
• Inventors: Levola, Tapani, Saarikko, Pasi
• Primary Examiner(s): Allen, Stephone
• Assistant Examiner(s): Kakalec, Kimberly N
• Application Number:
  US12/494,719
• Publication Number:
  US 20100328794A1
• Time in Patent Office: 1,071 Days
• Field of Search: 359/15, 359/566, 359/569, 359/571, 359/576, 359/630, 359/633
• US Class Current: 359/630
• CPC Class Codes: G02B 2027/0125 Field-of-view increase by wavefront division
• CPC Class Codes: G02B 27/0081 with means for altering, e.g. enlarging, the entrance or exit pupil
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/095 Refractive optical elements
• CPC Class Codes: G02B 5/18 Diffraction gratings holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44
• CPC Class Codes: G02B 6/00 Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings

Abstract

An apparatus and a method are provided. The apparatus including: a light expander configured to expand light, input into the light expander, in a first dimension, and configured to provide diverging light that diverges in the first dimension; and an optical device configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension.

Claims

1. An apparatus, comprising:

a light expander configured to expand light, input into the light expander, in a first dimension, and configured to provide diverging light that diverges in the first dimension;

an optical device configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension; and

a further light expander configured to expand the light, converging in the first dimension and received from the optical device, in a second dimension substantially orthogonal to the first dimension.

2. An apparatus as claimed in claim 1, wherein the light expander is configured to guide light, input into the light expander, prior to providing diverging light to the optical device.

3. An apparatus as claimed in claim 1, wherein the light expander is configured to expand light, input into the light expander, in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.

4. An apparatus as claimed in claim 1, wherein the optical device is configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension,

5. An apparatus as claimed in claim 1, wherein the optical device is configured to redirect the diverging light within a plane substantially orthogonal to the first dimension.

6. An apparatus as claimed in claim 1, wherein the optical device comprises a reflecting system comprising a plurality of reflecting surfaces.

7. An apparatus as claimed in claim 6, wherein adjacent reflecting surfaces of the reflecting system are orthogonal to one another.

8. An apparatus as claimed in claim 6, wherein the reflecting system is provided by a grooved reflector.

9. An apparatus as claimed in claim 1, wherein the light input into the light expander represents an image displayed on a display.

10. An apparatus as claimed in claim 1, wherein the further light expander comprises an in-coupling portion configured to receive the converging light from the optical device, and an out-coupling portion configured to output light to a user.

11. An apparatus as claimed in claim 10, wherein the in-coupling portion of the further light expander comprises a first grating and the out-coupling portion of the further light expander comprises a second grating.

12. An apparatus as claimed in claim 1, wherein the further light expander provides an exit pupil for the apparatus.

13. A method, comprising:

expanding light in a first dimension;

providing diverging light, that diverges in the first dimension;

redirecting the diverging light to produce converging light that converges in the first dimension; and

expanding the converging light in a second dimension, substantially orthogonal to the first dimension.

14. A method as claimed in claim 13, wherein the light is expanded in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.

15. A method as claimed in claim 13, wherein the diverging light is redirected to produce converging light that converges in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.

16. An apparatus, comprising:

light expanding means for expanding light, in a first dimension, and for providing diverging light that diverges in the first dimension; and

redirecting means for redirecting diverging light, received from the light expanding means, to produce converging light that converges in the first dimension; and

further light expanding means for expanding the light, converging in the first dimension and received from the redirecting means, in a second dimension substantially orthogonal to the first dimension.

17. An apparatus as claimed in claim 16, wherein the light expanding means is for expanding light, input into the light expander, in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.

18. An apparatus as claimed in claim 16, wherein the redirecting means is for redirecting diverging light, received from the light expander, to produce converging light that converges in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.

19. An apparatus, comprising:

a light expander configured to expand light, input into the light expander, in a first dimension, and configured to provide diverging light that diverges in the first dimension; and

a grooved reflector configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension.