Optical systems for electronic devices with displays

Patent metadata

Field	Value
Publication number	US-11740467-B2
Application number	US-202117231975-A
Country	US
Kind code	B2
Filing date	Apr 15, 2021
Priority date	Jun 6, 2017
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

An electronic device may have a pixel array. A light source may illuminate the pixel array to produce image light. The image light may pass through a multi-element lens and may be coupled into a waveguide using an input coupler such as a prism. An output coupler such as a diffraction grating may couple the image light out of the waveguide and towards a user. The user may view the image light and may observe real-world objects through the waveguide. The waveguide may have locally modified portions that define an aperture stop at a distance from an exit surface of the multi-element lens. The multi-element lens may have first and second achromatic doublets and first and second singlets between the first and second achromatic doublets. The lens elements of the multi-element lens may include lens elements with aspheric surfaces.

First claim

What is claimed is:

1. An electronic device, comprising:
a pixel array;
a light source that illuminates the pixel array to produce image light;
a lens having multiple lens elements including an initial lens element with an entrance surface that receives the image light and including a final lens element with an exit surface through which the image light exits; and
a waveguide that receives the image light from the final lens element, wherein the waveguide has a thickness, a length that is greater than the thickness, and a width that is greater than the thickness, wherein the waveguide has first and second opposing surfaces separated by the thickness, wherein the waveguide has first and second light blocking portions on the first surface that define an aperture stop for the image light, wherein the width is a first width, and wherein a second width that is smaller than the first width and parallel to the first width separates the first and second light blocking portions.

2. The electronic device defined in claim 1 , wherein the image light is configured to propagate along the length of the waveguide by reflecting off of the first and second opposing surfaces using total internal reflection.

3. The electronic device defined in claim 1 , wherein the length is a first length and wherein the first and second light blocking portions have a second length that is smaller than the first length and parallel to the first length.

4. The electronic device defined in claim 3 , wherein the aperture stop is at least three millimeters from the exit surface of the final lens element.

5. The electronic device defined in claim 4 , wherein the second length is at least three millimeters.

6. The electronic device defined in claim 1 , further comprising an input coupler configured to couple the image light into the waveguide from the final lens element.

7. The electronic device defined in claim 6 , further comprising an output coupler configured to couple the image light out of the waveguide.

8. The electronic device defined in claim 1 , further comprising a head-mounted support structure that supports the pixel array.

9. The electronic device defined in claim 1 , wherein the pixel array comprises a digital micromirror device.

10. The electronic device defined in claim 1 , wherein the multiple lens elements include:
a first achromatic doublet, wherein the first achromatic doublet includes the initial lens element;
a second achromatic doublet, wherein the second achromatic doublet includes the final lens element; and
first and second singlets between the first achromatic doublet and the second achromatic doublet.

11. The electronic device defined in claim 10 , wherein the first singlet has a first aspheric surface, wherein the second singlet has a second aspheric surface, and wherein the entrance surface of the initial lens element is a third aspheric surface.

12. The electronic device defined in claim 11 , wherein the initial lens element is a negative lens element.

13. An electronic device, comprising:
a pixel array;
a light source that illuminates the pixel array to produce image light;
a lens having multiple lens elements including an initial lens element with an entrance surface that receives the image light and including a final lens element with an exit surface through which the image light exits; and
a waveguide that receives the image light from the final lens element, wherein the waveguide has first and second light blocking portions that define an aperture stop for the image light, wherein the aperture stop is located at a distance from the exit surface, wherein the waveguide has a thickness, a length that is greater than the thickness, and a first width that is greater than the thickness, wherein the waveguide has first and second opposing surfaces separated by the thickness, wherein the image light is configured to propagate along the length of the waveguide by reflecting off of the first and second opposing surfaces using total internal reflection, wherein the first and second light blocking portions are formed on the first surface of the waveguide, and wherein a second width that is smaller than the first width and parallel to the first width separates the first and second light blocking portions.

14. The electronic device defined in claim 13 , wherein the distance is at least three millimeters.

15. The electronic device defined in claim 13 , wherein the length is a first length and wherein the first and second light blocking portions have a second length that is smaller than the first length and parallel to the first length.

Assignees

• Apple Inc

Inventors

• Peng Guolin
• Choi Hyungryul
• Delapp Scott M
• Anderson Tyler G

Classifications

• G02B27/0172 Primary

  characterised by optical features · CPC title

• G02B6/003

  Lens or lenticular sheet or layer · CPC title

• G02B6/0016

  Grooves, prisms, gratings, scattering particles or rough surfaces · CPC title

• G02B6/0018

  Redirecting means on the surface of the light guide · CPC title

• G02B6/0035

  provided on the surface of the light guide or in the bulk of it · CPC title