Biased total thickness variations in waveguide display substrates

Patent metadata

Field	Value
Publication number	US-11860416-B2
Application number	US-202217938869-A
Country	US
Kind code	B2
Filing date	Oct 7, 2022
Priority date	Feb 14, 2019
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

A plurality of waveguide display substrates, each waveguide display substrate having a cylindrical portion having a diameter and a planar surface, a curved portion opposite the planar surface defining a nonlinear change in thickness across the substrate and having a maximum height D with respect to the cylindrical portion, and a wedge portion between the cylindrical portion and the curved portion defining a linear change in thickness across the substrate and having a maximum height W with respect to the cylindrical portion. A target maximum height D t of the curved portion is 10 −7 to 10 −6 times the diameter, D is between about 70% and about 130% of D t , and W is less than about 30% of D t .

First claim

What is claimed is:

1. A waveguide display substrate comprising:
a cylindrical portion having a diameter and a planar surface; and
a curved portion opposite the planar surface, defining a nonlinear change in thickness across the substrate,
wherein a target maximum height D t of the curved portion is 10 −7 to 10 −6 times the diameter.

2. The waveguide display substrate of claim 1 , wherein D is a maximum height of the curved portion with respect to the cylindrical portion, and wherein D is between 70% and 130% of D t .

3. The waveguide display substrate of claim 1 , wherein the nonlinear change in thickness is a quadratic change in thickness.

4. The waveguide display substrate of claim 1 , wherein the curved portion in is the form of a dome.

5. The waveguide display substrate of claim 4 , wherein the dome is spherical.

6. The waveguide display substrate of claim 1 , wherein an average thickness of the waveguide display substrate is between about 200 microns and about 2000 microns.

7. The waveguide display substrate of claim 1 , wherein an average diameter of the waveguide display substrate is between about 2 centimeters and about 50 centimeters.

8. The waveguide display substrate of claim 1 , wherein the waveguide display substrate comprises a molded polymer.

9. The waveguide display substrate of claim 1 , wherein the waveguide display substrate comprises at least one of a polished glass, silicon, or a metal substrate.

10. A method comprising:
fabricating a waveguide display substrate such that the substrate comprises:
a cylindrical portion having a diameter and a planar surface; and
a curved portion opposite the planar surface and defining a nonlinear change in thickness across the substrate,
wherein the waveguide display substrate fabricated such as a target maximum height D t of the curved portion is 10 −7 to 10 −6 times the diameter.

11. The method of claim 10 , wherein D is a maximum height of the curved portion with respect to the cylindrical portion, and wherein the waveguide display substrate is fabricated such that D is between 70% and 130% of D t .

12. The method of claim 10 , wherein the waveguide display substrate is fabricated such that the nonlinear change in thickness is a quadratic change in thickness.

13. The method of claim 10 , wherein the waveguide display substrate is fabricated such that the curved portion in is the form of a dome.

14. The method of claim 13 , wherein the waveguide display substrate is fabricated such that the dome is spherical.

15. The method of claim 10 , wherein the waveguide display substrate is fabricated such that an average thickness of the waveguide display substrate is between about 200 microns and about 2000 microns.

16. The method of claim 10 , wherein the waveguide display substrate is fabricated such that an average diameter of the waveguide display substrate is between about 2 centimeters and about 50 centimeters.

17. The method of claim 10 , wherein the waveguide display substrate is fabricated using a molded polymer.

18. The method of claim 10 , wherein the waveguide display substrate is fabricated using at least one of a polished glass, silicon, or a metal substrate.

Assignees

• Magic Leap Inc

Inventors

• Bhargava Samarth
• Peroz Christophe
• LIU Victor Kai

Classifications

• G02B6/0046

  Tapered light guide, e.g. wedge-shaped light guide · CPC title

• G02B26/0891

  forming an optical wedge · CPC title

• G02B6/13 Primary

  Integrated optical circuits characterised by the manufacturing method · CPC title

• G02B6/122

  Basic optical elements, e.g. light-guiding paths · CPC title

• G02B6/1221

  made from organic materials · CPC title