MEMS mirror in series with resonant MEMS mirror to redistribute dense pixels

Patent metadata

Field	Value
Publication number	US-12282153-B2
Application number	US-202217578027-A
Country	US
Kind code	B2
Filing date	Jan 18, 2022
Priority date	Jan 18, 2022
Publication date	Apr 22, 2025
Grant date	Apr 22, 2025

Abstract

A near-eye display system employs a low-amplitude, low-frequency micro-electromechanical system (MEMS) mirror in series with a higher-amplitude, higher-frequency resonant MEMS mirror to rotate at a reduced amplitude and frequency with respect to the resonant MEMS mirror redistribute illumination pulses or pixels at the extents of a sinusoidal angular scan pattern of the resonant MEMS mirror.

First claim

What is claimed is:

1. A near-eye display system comprising:
a waveguide having an incoupler (IC);
a first micro-electromechanical system (MEMS) mirror to receive collimated light and rotate about a first axis at a first amplitude and at a first frequency to generate scanned light having a first range of scan angles; and
a second MEMS mirror in series with the first MEMS mirror to rotate about a second axis in a sinusoidal pattern at a second amplitude and at a second frequency to direct the scanned light to the IC to represent pixels of an image, wherein the second frequency differs by at least 0.5% from the first frequency and wherein the first MEMS mirror redistributes the pixels of the image.

2. The near-eye display of claim 1 , wherein the second amplitude is greater than the first amplitude.

3. The near-eye display of claim 1 , wherein the second frequency is higher than the first frequency.

4. The near-eye display of claim 1 , wherein the first MEMS mirror is a linear MEMS mirror.

5. The near-eye display of claim 1 , further comprising:
a light source to generate the collimated light, wherein the light source is to remain energized throughout the rotation by the second MEMS mirror in the sinusoidal pattern.

6. The near-eye display of claim 1 , wherein the first amplitude is based on the second amplitude and the presence of an optical relay between the first MEMS mirror and the second MEMS mirror.

7. A display system comprising:
a waveguide having an incoupler (IC); and
a first of micro-electromechanical system (MEMS) mirror configured to receive collimated light and rotate across a first range of angles at a first frequency and at a first amplitude to scan the light along scan angles corresponding to the first range of angles; and
a second MEMS mirror in series with the first MEMS mirror to receive the scanned light and rotate across a second range of angles in a sinusoidal pattern at a second frequency and at a second amplitude, the second frequency different by at least 0.5% from the first frequency and the second amplitude different from the first amplitude, to direct the scanned light to one or more input angles at the IC to generate pixels an image.

8. The display system of claim 7 , wherein the first MEMS mirror is a linear MEMS mirror.

9. The display system of claim 7 , further comprising:
a light source to generate the collimated light, wherein the light source is to remain energized throughout the rotation by the second MEMS mirror across the second range of angles.

10. The display system of claim 7 , wherein the first amplitude is based on the second amplitude and the presence of an optical relay between the first MEMS mirror and the second MEMS mirror.

11. The display system of claim 7 , wherein the first MEMS mirror redistributes the pixels of the image.

12. A method, comprising:
receiving collimated light at a first micro-electromechanical system (MEMS) mirror;
rotating the first MEMS mirror about a first axis at a first amplitude and at a first frequency to generate scanned light having a first range of scan angles;
receiving the scanned light at a second MEMS mirror in series with the first MEMS mirror; and
rotating the second MEMS mirror across a second range of angles in a sinusoidal pattern at a second frequency and at a second amplitude, the second frequency differing by at least 0.5% from the first frequency and the second amplitude different from the first amplitude, to direct the scanned light to one or more input angles at an incoupler of a waveguide to generate pixels of an image.

13. The method of claim 12 , wherein the first MEMS mirror is a linear MEMS mirror.

14. The method of claim 12 , further comprising:
generating the collimated light at a light source, wherein the light source is to remain energized throughout the rotation by the second MEMS mirror across the second range of angles.

15. The method of claim 12 , wherein the first amplitude is based on the second amplitude and the presence of an optical relay between the first MEMS mirror and the second MEMS mirror.

16. The method of claim 12 , wherein the first MEMS mirror redistributes the pixels of the image.

17. The method of claim 16 , wherein the first MEMS mirror shifts the pixels of the image from the extents of a sinusoidal angular scan pattern of the second MEMS to the center of the sinusoidal angular scan pattern.

Assignees

• Google Llc

Inventors

• Adema Daniel

Classifications

• G02B2027/0178

  Eyeglass type (eyeglass details G02C) · CPC title

• G02B2027/0154

  with movable elements · CPC title

• G02B27/0176

  characterised by mechanical features · CPC title

• G02B27/0172

  characterised by optical features · CPC title

• G02B26/101

  with both horizontal and vertical deflecting means, e.g. raster or XY scanners (colour television using laser beams scanning a display screen H04N9/3129) · CPC title