Display system with a single plate optical waveguide and independently adjustable micro display arrays

• US 10,546,523 B2
• Filed: 06/22/2018
• Issued: 01/28/2020
• Est. Priority Date: 06/22/2018
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Bohn, David D.
• Primary Examiner(s): Khan, Ibrahim A
• Application Number:
  US16/016,366
• Publication Number:
  US 20190392746A1
• Time in Patent Office: 585 Days
• CPC Class Codes: G02B 2027/0112 comprising device for genereting colour display
• CPC Class Codes: G02B 2027/0116 comprising devices for correcting chromatic aberration
• CPC Class Codes: G02B 2027/0178 Eyeglass type eyeglass details G02C
• CPC Class Codes: G02B 27/0081 with means for altering, e.g. enlarging, the entrance or exit pupil
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 6/0026 Wavelength selective element, sheet or layer, e.g. filter or grating
• CPC Class Codes: G02B 6/003 Lens or lenticular sheet or layer
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]

Abstract

Display systems with a single plate optical waveguide and independently adjustable micro display arrays and related methods are provided. A method includes coupling: a first light portion received from the first micro display array to a first input grating region of the optical waveguide, a second light portion received from the second micro display array to a second input grating region of the optical waveguide, and a third light portion received from the third micro display array to a third input grating region of the optical waveguide. The method further includes directing: a first diffracted portion of the first light portion to a first expansion grating, a second diffracted portion of the second light portion to a second expansion grating, and a third diffracted portion of the third light portion to a third expansion grating. The method further includes using a single output grating outputting combined light.

Claims

1. An apparatus comprising:

a first micro display array corresponding to a red color channel;

a second micro display array corresponding to a green color channel;

a third micro display array corresponding to a blue color channel; and

an optical waveguide including a first surface and a second surface opposite to the first surface, the optical waveguide further comprising;

a first input grating region configured to receive a first light portion corresponding to the red color channel,

a second input grating region configured to receive a second light portion corresponding to the blue color channel, wherein the second input grating region is offset from the first input grating region by a first offset,

a third input grating region configured to receive a third light portion corresponding to the green color channel, wherein the third input grating region is offset from the second input grating region by a second offset,

a first set of expansion gratings, formed on the first major surface of the optical waveguide, configured to receive a first diffracted light portion of the first light portion from the first input grating region,

a second set of expansion gratings, formed on the first major surface of the optical waveguide, configured to receive a second diffracted light portion of the second light portion from the second input grating region, and

a third set of expansion gratings, formed on the second major surface of the optical waveguide, configured to receive a third diffracted light portion of the third light portion from the third input grating region.

2. The apparatus of claim 1 further comprising a first projection lens coupled to the first micro display array, a second projection lens coupled to the second micro display array, and a third projection lens coupled to the third micro display array.

3. The apparatus of claim 1 further comprising an output grating configured to combine light received from each of the first set of expansion gratings, the second set of expansion gratings, and the third set of expansion gratings to generate combined light corresponding to a field of view of the apparatus and output combined light out of the optical waveguide.

4. The apparatus of claim 1, wherein the optical waveguide is a single plate surface reflective grating.

5. The apparatus of claim 1, wherein the first input grating region is arranged in an opposite direction to the second input grating region.

6. The apparatus of claim 1, wherein each of the first micro display array, the second micro display array, and the third micro display array comprises a micro-LED array.

7. The apparatus of claim 3 further comprising a display controller configured to independently adjust at least one of:

a first display parameter related to a first set of pixels corresponding to the first micro display array, a second display parameter related to a second set of pixels corresponding to the second micro display array, or a third display parameter related to a third set of pixels corresponding to the third micro display array to at least improve a uniformity of the combined light.

8. An apparatus comprising:

a first micro display array corresponding to a red color channel;

a second micro display array corresponding to a green color channel;

a third micro display array corresponding to a blue color channel; and

an optical waveguide including a first surface and a second surface opposite to the first surface, the optical waveguide further comprising;

a first input grating region configured to receive a first light portion corresponding to the red color channel,

a second input grating region configured to receive a second light portion corresponding to the blue color channel, wherein the second input grating region is offset from the first input grating region by a first offset,

a third input grating region configured to receive a third light portion corresponding to the green color channel, wherein the third input grating region is offset from the second input grating region by a second offset,

a first expansion grating, formed on the first major surface of the optical waveguide, configured to receive a first diffracted light portion of the first light portion from the first input grating region,

a second expansion grating, formed on the first major surface of the optical waveguide, configured to receive a second diffracted light portion of the second light portion from the second input grating region,

a third expansion grating, formed on the second major surface of the optical waveguide, configured to receive a third diffracted light portion of the third light portion from the third input grating region, and

an output grating configured to combine light received from each of the first expansion grating, the second expansion grating, and the third expansion grating to generate combined light corresponding to a field of view of the apparatus and output combined light out of the optical waveguide.

9. The apparatus of claim 8 further comprising a first projection lens coupled to the first micro display array, a second projection lens coupled to the second micro display array, and a third projection lens coupled to the third micro display array.

10. The apparatus of claim 8, wherein the optical waveguide is a single plate surface reflective grating.

11. The apparatus of claim 8, wherein the first input grating region is arranged in an opposite direction to the second input grating region.

12. The apparatus of claim 8, wherein each of the first micro display array, the second micro display array, and the third micro display array comprises a micro-LED array.

13. The apparatus of claim 8 further comprising a display controller configured to adjust independently at least one of:

a first display parameter related to a first set of pixels corresponding to the first micro display array, a second display parameter related to a second set of pixels corresponding to the second micro display array, or a third display parameter related to a third set of pixels corresponding to the third micro display array to at least improve a uniformity of the combined light.

14. A method in an apparatus comprising a display controller, an optical waveguide, a first micro display array, a second micro display array, and a third micro display array, the method comprising:

coupling;

a first light portion received from the first micro display array to a first input grating region of the optical waveguide, a second light portion received from the second micro display array to a second input grating region of the optical waveguide, and a third light portion received from the third micro display array to a third input grating region of the optical waveguide;

directing;

a first diffracted portion of the first light portion to a first expansion grating, a second diffracted portion of the second light portion to a second expansion grating, and a third diffracted portion of the third light portion to a third expansion grating;

using a single output grating combining light received from each of the first expansion grating, the second expansion grating, the third expansion grating, and outputting combined light corresponding to a field of view of an apparatus incorporating the optical waveguide; and

in response to at least one uniformity control signal, using a controller associated with the apparatus, adjusting independently at least one of;

a first display parameter related to a first set of pixels corresponding to the first micro display array, a second display parameter related to a second set of pixels corresponding to the second micro display array, or a third display parameter related to a third set of pixels corresponding to the third micro display array to at least improve a uniformity of the combined light.

15. The method of claim 14 further comprising:

using a first projection lens coupled to the first micro display array, collimating a first emitted light portion from the first micro display array onto the first input grating region, using a second projection lens coupled to the second micro display array, collimating a second emitted light portion from the second micro display array onto the second input grating region, and using a third projection lens coupled to the third micro display array, collimating a third emitted light portion from the third micro display array onto the third input grating region.

16. The method of claim 14, wherein the optical waveguide is a single plate surface reflective grating.

17. The method of claim 14 further comprising rendering the collected light into content for display in the field of view of the apparatus incorporating the optical waveguide.

18. The method of claim 14, wherein the optical waveguide comprises a first major surface and a second major surface opposite to the first major surface, wherein the first expansion grating is formed on the first major surface of the optical waveguide, wherein the second expansion grating is formed on the first major surface of the optical waveguide, and wherein the third expansion grating is formed on the second major surface of the optical waveguide.

19. The method of claim 14, wherein each of the first micro display array, the second micro display array, and the third micro display array comprises a micro-LED array.

20. The method of claim 14 further comprising calibrating color uniformity independently for each of the first micro display array, the second micro display array, and the third micro display array.