Laser projection unit, depth camera and electronic device

Patent metadata

Field	Value
Publication number	US-10962870-B2
Application number	US-201916467145-A
Country	US
Kind code	B2
Filing date	Feb 18, 2019
Priority date	Mar 12, 2018
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

A laser projection unit, a depth camera and an electronic device are provided. The laser projection unit includes a light source, a collimation element and a diffractive optical element. The light source is configured to emit laser. The collimation element is configured to collimate the laser. The collimation element includes one or a plurality of lenses provided in a light emitting path of the light source. The diffractive optical element is configured to diffract the laser collimated by the diffractive collimation element to form a laser pattern.

First claim

What is claimed is:

1. A laser projection unit, comprising:
a light source configured to emit laser;
a collimation element configured to collimate the laser, and the collimation element comprising a plurality of lenses, the plurality of lenses being provided in a light emitting path of the light source; and
a diffractive optical element configured to diffract the laser collimated by the collimation element to form a laser pattern;
wherein the plurality of the lenses comprise at least one first type lens and at least one second type lens, the first type lens is made of glass, and the second type lens is made of plastic,
wherein the plurality of lenses comprise a first lens, a second lens and a third lens, the first lens, the second lens and the third lens are provided in the light emitting path of the light source in sequence, an optical axis of the second lens is offset relative to an optical axis of the first lens, and the optical axis of the first lens coincides with an optical axis of the third lens;
the laser projection unit further comprises a lens barrel, the lens barrel comprises a first segment structure and a second segment structure, the first segment structure is connected to the second segment structure in an inclined manner, the first segment structure is configured to install the first lens and the second lens, and the second segment structure is configured to install the third lens, inner walls of the first segment structure and the second segment structure are coated with reflective coatings for reflecting lights, such that lights emitted by the light source is capable of passing through the first lens, the second lens and the third lens in sequence.

2. The laser projection unit according to claim 1 , wherein the collimation element comprises the plurality of lenses provided in the light emitting path of the light source in sequence, an optical axis of at least one of the plurality of lenses is offset relative to an optical axis of each other of the plurality of lenses.

3. The laser projection unit according to claim 1 , wherein the collimation element comprises the plurality of lenses, optical centers of at least two of the lenses are located in the same plane perpendicular to a first direction, and the first direction is a direction from the light source to the diffractive optical element.

4. The laser projection unit according to claim 1 , wherein the light source is a vertical cavity surface emitting laser; or the light source is an edge-emitting laser.

5. The laser projection unit according to claim 1 , wherein the light source is the edge-emitting laser, the light source comprises the light emitting face, and the light emitting face faces the light collimation element.

6. The laser projection unit according to claim 1 , wherein the laser projection unit further comprises a substrate assembly and a lens barrel, the lens barrel is provided to the substrate assembly and defines an accommodating chamber together with the substrate assembly, and the light source, the collimation element and the diffractive optical element are accommodated in the accommodating chamber.

7. The laser projection unit according to claim 6 , wherein the substrate assembly comprises a substrate and a circuit board supported on the substrate, the circuit board defines a hole therein, and the light source is supported on the substrate and accommodated in the hole.

8. A depth camera, comprising:
a laser projection unit comprising:
a light source configured to emit laser;
a collimation element configured to collimate the laser, and the collimation element comprising a plurality of lenses provided in a light emitting path of the light source; and
a diffractive optical element configured to diffract the laser collimated by the collimation element to form a laser pattern;

an image acquirer configured to acquire a laser pattern projected into a target space after passing through the diffractive optical element; and
a processor coupled to the laser projection unit and the image acquirer separately, the processor being configured to process the laser pattern to obtain a depth image;
wherein the plurality of the lenses comprise at least one first type lens and at least one second type lens, the first type lens is made of glass, and the second type lens is made of plastic,
wherein the plurality of lenses comprise a first lens, a second lens and a third lens, the first lens, the second lens and the third lens are provided in the light emitting path of the light source in sequence, an optical axis of the second lens is offset relative to an optical axis of the first lens, and the optical axis of the first lens coincides with an optical axis of the third lens;
the laser projection unit further comprises a lens barrel, the lens barrel comprises a first segment structure and a second segment structure, the first segment structure is connected to the second segment structure in an inclined manner, the first segment structure is configured to install the first lens and the second lens, and the second segment structure is configured to install the third lens, inner walls of the first segment structure and the second segment structure are coated with reflective coatings for reflecting lights, such that lights emitted by the light source is capable of passing through the first lens, the second lens and the third lens in sequence.

9. An electronic device, comprising:
a housing; and
a depth camera comprising:
a laser projection unit comprising:
a light source configured to emit laser;
a collimation element configured to collimate the laser, and the collimation element comprising a plurality of lenses provided in a light emitting path of the light source; and
a diffractive optical element configured to diffract the laser collimated by the collimation element to form a laser pattern;

an image acquirer configured to acquire a laser pattern projected into a target space after passing through the diffractive optical element; and
a processor coupled to the laser projection unit and the image acquirer separately, the processor being configured to process the laser pattern to obtain a depth image,

the depth camera being provided in the housing and exposed out of the housing to acquire the depth image;
wherein the plurality of the lenses comprise at least one first type lens and at least one second type lens, the first type lens is made of glass, and the second type lens is made of plastic,
wherein the plurality of lenses comprise a first lens, a second lens and a third lens, the first lens, the second lens and the third lens are provided in the light emitting path of the light source in sequence, an optical axis of the second lens is offset relative to an optical axis of the first lens, and the optical axis of the first lens coincides with an optical axis of the third lens;
the laser projection unit further comprises a lens barrel, the lens barrel comprises a first segment structure and a second segment structure, the first segment structure is connected to the second segment structure in an inclined manner, the first segment structure is configured to install the first lens and the second lens, and the second segment structure is configured to install the third lens, inner walls of the first segment structure and the second segment structure are coated with reflective coatings for reflecting lights, such that lights emitted by the light source is capable of passing through the first lens, the second lens and the third lens in sequence.

10. The laser projection unit according to claim 1 , wherein the collimation element comprises a first lens, the first lens comprises a first light incident face and first light emitting face oppos

Assignees

• Guangdong Oppo Mobile Telecommunications Corp Ltd

Inventors

• Wei Yi

Classifications

• H04N23/55

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• G03B17/54

  with projector · CPC title

• G03B21/2033 Primary

  LED or laser light sources · CPC title

• G02B27/30

  Collimators · CPC title

• H01S5/423

  having a vertical cavity · CPC title