Multifunction light projector with multistage adjustable diffractive optical elements

Patent metadata

Field	Value
Publication number	US-11022813-B2
Application number	US-201916378255-A
Country	US
Kind code	B2
Filing date	Apr 8, 2019
Priority date	Apr 8, 2019
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

Aspects of the present disclosure relate to a device including a light projector. An example light projector includes a light source that emits a light, a first diffractive optical element block comprising a first diffractive optical element and a first refractive material, and a second diffractive optical element block comprising a second diffractive optical element and a second refractive material. The first diffractive optical element is configured to project a first distribution of light, and the first refractive material is configured to switch the first diffractive optical element between projecting the first distribution of light and being prevented from projecting the first distribution of light. The second diffractive optical element is configured to project a second distribution of light, and the second refractive material is configured to switch the second diffractive optical element between projecting the second distribution of light and being prevented from projecting the second distribution of light.

First claim

What is claimed is:

1. A device comprising a light projector, the light projector comprising:
a light source configured to emit a light;
a first diffractive optical element block positioned to receive light from the light source, the first diffractive optical element block comprising:
a first diffractive optical element configured to project a first distribution of light from the emitted light; and
a first refractive material configured to switch the first diffractive optical element between projecting the first distribution of light and being prevented from projecting the first distribution of light; and

a second diffractive optical element block positioned to receive light from the first diffractive optical element block, the second diffractive optical element block comprising:
a second diffractive optical element configured to project a second distribution of light from the emitted light; and
a second refractive material configured to switch the second diffractive optical element between projecting the second distribution of light and being prevented from projecting the second distribution of light,
wherein the light projector is configured to transition between a plurality of modes using at least one of the first diffractive optical element block and the second diffractive optical element block.

2. The device of claim 1 , wherein the first refractive material is positioned between the light source and the first diffractive optical element, and wherein the second refractive material is positioned between the first diffractive optical element and the second diffractive optical element.

3. The device of claim 1 , wherein the emitted light that enters the first refractive material has a first polarity in a first mode of the plurality of modes and wherein the emitted light that enters the second refractive material has a second polarity in a second mode of the plurality of modes, wherein the first polarity is rotated relative to the second polarity.

4. The device of claim 3 , further comprising:
a first polarity rotator between the light source and the first refractive material, the first polarity rotator configured to rotate the first polarity based on a first refractive index of the first refractive material; and
a second polarity rotator between the first diffractive optical element and the second refractive material, the second polarity rotator configured to rotate the second polarity based on a second refractive index of the second refractive material.

5. The device of claim 1 , further comprising a diffractive element comprising at least the first diffractive optical element block, the second diffractive optical element block, and a fixed diffractive optical element between the light source and the first diffractive optical element, the fixed diffractive optical element configured to project a fixed distribution of light from the emitted light during all of the plurality of modes.

6. The device of claim 1 , further comprising a diffractive element comprising at least the first diffractive optical element block, the second diffractive optical element block, and a third diffractive optical element block including at least a third diffractive optical element and a third refractive material between the second diffractive optical element and the third diffractive optical element, the third diffractive optical element configured to project a combined distribution of the first and second distributions of light.

7. The device of claim 1 , wherein:
during a first mode of the plurality of modes, the first diffractive optical element is activated, the second diffractive optical element is deactivated, and the light projector is configured to project a first projection,
during a second mode of the plurality of modes, the first diffractive optical element is deactivated, the second diffractive optical element is activated, and the light projector is configured to project a second projection,
during a third mode of the plurality of modes, each of the first and second diffractive optical elements are activated, and the light projector is configured to project a third projection including at least the first and second projections, and
during a fourth mode of the plurality of modes, each of the first and second diffractive optical elements are deactivated.

8. The device of claim 1 , wherein:
the first diffractive optical element block further comprises a first conductive material coupled to the first refractive material, the first conductive material configured to receive a first signal that applies a first voltage to the first refractive material to transition a state of the light projector to a first mode of the plurality of modes, and
the second diffractive optical element block further comprises a second conductive material coupled to the second refractive material, the second conductive material configured to receive a second signal that applies a second voltage to the second refractive material to transition the state of the light projector to a second mode of the plurality of modes.

9. The device of claim 1 , wherein the first and second refractive material each comprise a liquid crystal including liquid crystal molecules having a first overall orientation when electricity is applied and having a second overall orientation when electricity is not applied.

10. The device of claim 1 , wherein the plurality of modes comprise the light projector projecting at least one projection from the group consisting of: a flood illumination, a distribution having a first resolution, and a distribution having a second resolution different from the first resolution.

11. The device of claim 1 , wherein the light source is configured to emit infrared light.

12. The device of claim 11 , further comprising an infrared receiver configured to receive reflections of the infrared light emitted by the light source.

13. The device of claim 12 , further comprising one or more processors configured to control the light projector, wherein the device is a wireless communication device comprising one or more wireless transceivers.

14. The device of claim 1 , wherein the first diffractive optical element block further comprises a polarity rotator configured to rotate a polarity of the received light, wherein the first diffractive optical element diffracts the received light when the polarity rotator rotates the polarity to a first polarization, and wherein the first diffractive optical element does not affect the received light when the polarity rotator rotates the polarity to a second polarization.

15. The device of claim 1 , wherein the first diffractive optical element block comprises a liquid crystal (LC) having a number of molecules, and wherein an orientation of the number of molecules is based on whether a pair of electrodes is applying a voltage to the LC.

16. A method, comprising:
emitting a light by a light source of a light projector;
projecting, by a first diffractive optical element of a first diffractive optical element block of the light projector, a first distribution of light from the emitted light, the first diffractive optical element block positioned to receive light from the light source;
switching, by a first refractive material of the first diffractive optical element block, the first diffractive optical element between projecting the first distribution of light and being prevented from projecting the first distribution of light;
projecting, by a second diffractive optical element of a second diffractive optical element block of the light projector, a second distribution of light from the emitted

Assignees

• Qualcomm Inc

Inventors

• Ma Jian

Classifications

• H04M1/0272

  for a projector or beamer module assembly (constructional features of projectors per se G03B21/00; constructional details of projectors using electronic spatial light modulators per se H04N9/31) · CPC title

• G02F2203/62

  Switchable arrangements whereby the element being usually not switchable · CPC title

• G02F2203/22

  diffractive · CPC title

• G02F2203/11

  involving infrared radiation · CPC title

• G02F2201/58

  Arrangements comprising a monitoring photodetector · CPC title