Light output system with reflector and lens for highly spatially uniform light output

Patent metadata

Field	Value
Publication number	US-11378256-B2
Application number	US-201916378409-A
Country	US
Kind code	B2
Filing date	Apr 8, 2019
Priority date	Feb 26, 2016
Publication date	Jul 5, 2022
Grant date	Jul 5, 2022

Abstract

In some embodiments, optical systems with a reflector and a lens proximate a light output opening of the reflector provide light output with high spatial uniformity and high efficiency. The reflectors are shaped to provide substantially angularly uniform light output and the lens is configured to transform this angularly uniform light output into spatially uniform light output. The light output may be directed into a spatial light modulator, which modulates the light to project an image.

First claim

What is claimed is:

1. A display system comprising:
a light emitter;
a reflector optically coupled to the light emitter and configured to receive light from the light emitter, the reflector configured to output light with increased angular uniformity relative to light received from the light emitter;
a lens optically coupled to the reflector and configured to receive light from the reflector, the lens configured to output light with increased spatial uniformity relative to light output from the reflector;
a spatial light modulator configured to receive light from the lens and to modulate the light received from the lens to create an image; and
a stack of waveguides, wherein each waveguide of the stack comprises a light incoupling optical element configured to incouple light from an associated light emitter via the light modulating device.

2. The display system of claim 1 , wherein the reflector is one of a plurality of reflectors formed as openings extending across a thickness of a common unitary body, wherein each reflector has an associated lens forward of the output opening of the reflector.

3. The display system of claim 1 , wherein the spatial light modulator comprises a liquid crystal display (LCD).

4. The display system of claim 3 , wherein the liquid crystal display is a liquid crystal on silicon (LCoS) display.

5. The display system of claim 1 , wherein the light source is a light emitting diode.

6. A display system comprising:
a light emitter;
a reflector optically coupled to the light emitter and configured to receive light from the light emitter, the reflector configured to output light with increased angular uniformity relative to light received from the light emitter;
a lens optically coupled to the reflector and configured to receive light from the reflector, the lens configured to output light with increased spatial uniformity relative to light output from the reflector; and
a spatial light modulator configured to receive light from the lens and to modulate the light received from the lens to create an image,
wherein the reflector is one of a plurality of reflectors formed as openings extending across a thickness of a common unitary body, wherein each reflector has an associated lens forward of the output opening of the reflector,
wherein the unitary body has a multi-tiered surface, wherein some reflectors have output openings on a different tier than other reflectors.

7. The display system of claim 6 , wherein each reflector has an associated light emitter, wherein some light emitters are configured to emit light of different wavelengths than other light emitters, wherein a height of the tiers varies depending upon a wavelength of light emitted by an associated light emitter.

8. The display system of claim 7 , wherein the light emitters form three or more groups of light sources, wherein each group emits light of a same color.

9. The display system of claim 8 , wherein the light emitters form three groups of light sources, wherein light emitters of a first of the groups emit red light, wherein light emitters of a second of the groups emit green light, and wherein light emitters of a third of the groups emit blue light.

10. A display system comprising:
a light emitter;
a reflector optically coupled to the light emitter and configured to receive light from the light emitter, the reflector configured to output light with increased angular uniformity relative to light received from the light emitter;
a lens optically coupled to the reflector and configured to receive light from the reflector, the lens configured to output light with increased spatial uniformity relative to light output from the reflector;
a spatial light modulator configured to receive light from the lens and to modulate the light received from the lens to create an image; and
a mask between the reflector and the spatial light modulator.

11. The display system of claim 10 , wherein the light emitter is one of a plurality of light emitters,
further comprising a stack of waveguides, wherein each waveguide of the stack comprises a light incoupling optical element configured to incouple light from an associated light emitter of the plurality of light emitters via the light modulating device.

12. The display system of claim 11 , wherein different light incoupling optical elements are in a path of light of different light emitters.

13. The display system of claim 11 , wherein each waveguide of the stack of waveguides comprises a light outcoupling optical element, wherein light outcoupling optical elements of some waveguides are configured to output light with different amounts of divergence than light outcoupling optical element of some of the other waveguides of the stack of waveguides.

14. The display system of claim 10 , wherein the mask is between the lens and the spatial light modulator.

15. A display system comprising:
a plurality of reflectors, each reflector comprising:
an input end;
an output end;
an even number of faceted sides extending between the input end and the output end, wherein two opposing sides of the reflector have a first cross-sectional profile and the remaining sides have a second cross-sectional profile different from the first cross-section profile;

a plurality of light emitters, each light emitter located at an input end of an associated one of the plurality reflectors;
a plurality of lenses, each lens disposed at an output end of an associated one of the plurality of reflectors and located one focal length away from an associated light emitter of the associated one of the plurality of reflectors;
a light modulating device configured to receive light output from the plurality of lens; and
a stack of waveguides, wherein each waveguide of the stack comprises:
a light incoupling optical element configured to incouple light received from an associated one of the plurality of light emitters via the light modulating device, wherein different light incoupling optical elements are in a path of light of different ones of the plurality of light emitters; and
a light outcoupling optical element,
wherein light outcoupling optical elements of some waveguides are configured to output light with different amounts of divergence than light outcoupling optical element of some of the other waveguides of the stack of waveguides.

16. The display system of claim 15 , wherein the first cross-sectional profile is a first compound parabolic concentrator (CPC) profile.

17. The display system of claim 16 , wherein the second cross-sectional profile is a second compound parabolic concentrator (CPC) profile, wherein the first and the second CPC profiles are different.

18. The display system of claim 15 , wherein a cross-sectional shape of the input end is different from a cross-sectional shape of the output end.

Assignees

• Magic Leap Inc

Inventors

• Sissom Bradley Jay
• Hall Heidi Leising
• Curtis Kevin

Classifications

• G02B30/50

  the image being built up from image elements distributed over a three-dimensional [3D] volume, e.g. voxels · CPC title

• H04N13/344

  with head-mounted left-right displays · CPC title

• G02B27/0172

  characterised by optical features · CPC title

• H04N13/315

  the parallax barriers being time-variant · CPC title

• F21V13/04 Primary

  the elements being reflectors and refractors {(for vehicle rear lights F21S43/40)} · CPC title