CN210776057U

CN210776057U - VCSEL (vertical cavity surface emitting laser) one-line laser projection system

Info

Publication number: CN210776057U
Application number: CN201921895206.XU
Authority: CN
Inventors: 刘志颖; 吴东岷
Original assignee: China Science Fusion Perception Intelligence Research Institute Suzhou Industrial Park Co ltd
Current assignee: China Science Fusion Perception Intelligence Research Institute Suzhou Industrial Park Co ltd
Priority date: 2019-11-06
Filing date: 2019-11-06
Publication date: 2020-06-16
Anticipated expiration: 2029-11-06

Abstract

The utility model relates to a VCSEL (vertical cavity surface emitting laser) line laser projection system, which comprises an area array VCSEL, a line lens and a receiving screen; the width direction of the area array VCSEL is in a YZ plane in a rectangular coordinate system, and the length direction of the area array VCSEL is in an XZ plane; the front surface of the word line lens is a rotationally symmetric even-order aspheric surface; the back surface of the word line lens is an even order aspheric cylindrical surface; the generatrix of the even aspheric cylindrical surface is in an XZ plane in a rectangular coordinate system, and the stretching direction is along the Y direction; after light beams emitted by each light emitting point of the area array VCSEL are collimated by a rotationally symmetric even aspheric surface, the light beams are stretched and homogenized in the length direction of the light emitting point array by an even aspheric cylindrical surface, the light transmission direction in a YZ plane is unchanged, and finally a word line laser is projected on a receiving screen; the utility model weakens the laser speckle inside the word line and improves the quality of the projected word line; meanwhile, an additional speckle dispersing device is not added in the system, so that the system is simple in structure, low in cost and small in size.

Description

VCSEL (vertical cavity surface emitting laser) one-line laser projection system

Technical Field

The utility model relates to a VCSEL word line laser projection system belongs to laser beam plastic technical field.

Background

With the popularization of structured light, the one-line laser projection system is increasingly applied to depth detection and 3D perception in the industrial and consumer electronics industries, this requires a narrower width of a word line laser, higher uniformity and higher brightness, meanwhile, the system tends to be more and more miniaturized, and the conventional one-line laser projection system mostly uses a single-mode Laser Diode (LD) as a light source of one line, however due to the good monochromaticity and coherence of laser, when light from the LD is irradiated to a rough surface of a general object, speckle is formed on the surface of the object due to interference of the light, therefore, a granular structure is generated inside the word line light spot, the word line quality is reduced, the calculation results of depth detection and 3D perception are directly influenced, and a corresponding solution is not provided for the internal speckles of the word line by the word line laser projection system on the market at present.

The Vertical Cavity Surface-Emitting Laser (VCSEL for short) is a semiconductor Laser, a Surface is distributed with luminous point array, the light is emitted out perpendicular to the top Surface, and the VCSEL chip is a Surface-Emitting Laser, compared with an edge-Emitting Laser diode, the VCSEL chip has the advantages of good mode, low gate current, good stability, long service life, high modulation rate, high integration, small divergence angle, high coupling efficiency, low price and the like.

The chinese utility model patent CN106019620A discloses a device for suppressing laser speckle and a laser projection device, the device has a plurality of groups of module assemblies, the temperature of the semiconductor laser in each group of module assemblies has difference, so that the wavelength of the laser with the same color output by the semiconductor laser in each group of module assemblies is different, and a certain difference appears, thereby effectively suppressing the laser speckle effect; the main disadvantages of this method are as follows: multiple groups of semiconductor lasers and temperature control devices are needed, the cost is high, the size is difficult to be reduced, and multi-wavelength lasers also put higher requirements on the suppression of optical system dispersion.

The chinese utility model patent CN108873368A discloses a method for suppressing laser speckles and a MEMS micro-vibration mirror, which can realize auxiliary motion (micro translation perpendicular to the mirror surface direction or micro motion twisted around the y axis) while twisting around the twisting axis by optimizing the structure of the conventional MEMS micro-vibration mirror, and reduce the beam coherence while deflecting the incident beam, thereby realizing the suppression function of laser speckles under the condition of satisfying the working requirements of the optical system; the method can only be applied to a system containing the MEMS micro-vibrating mirror and has large limitation.

The existing line laser projection system has the defects that the light source is mostly an edge-emitting laser diode, projected line light spots have a serious speckle effect, the existing line projection system does not have a special solution for solving the problem, and other schemes for inhibiting speckles are high in cost and difficult to reduce in size, or special elements are used for an optical system, so that the limitation is large.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the purpose provides a VCSEL word line laser projection system in order to overcome prior art not enough, simple structure, and the cost is lower, and is small, has restrained the speckle effect of a word line facula, has improved the quality of a word line that throws out.

In order to achieve the above purpose, the utility model adopts the technical scheme that: a VCSEL-wordline laser projection system comprises an area array VCSEL, a wordline lens and a receiving screen; the width direction of the area array VCSEL is in a YZ plane in a rectangular coordinate system, and the length direction of the area array VCSEL is in an XZ plane; the front surface of the word line lens is a rotationally symmetric even-order aspheric surface; the back surface of the word line lens is an even order aspheric cylindrical surface; the generatrix of the even aspheric cylindrical surface is in an XZ plane in a rectangular coordinate system, and the stretching direction is along the Y direction; after light beams emitted by each light emitting point of the area array VCSEL are collimated by a rotationally symmetric even aspheric surface, the light beams are stretched and homogenized in the length direction of the light emitting point array through an even aspheric cylindrical surface, the light transmission direction in a YZ plane is unchanged, and finally a word line laser is projected on a receiving screen.

Preferably, the generatrix of the even-order aspheric cylindrical surface is consistent with the length direction of the area array VCSEL light emitting point array.

Because of above-mentioned technical scheme's application, compared with the prior art, the utility model have the following advantage:

the VCSEL-based line laser projection system adopts the area array VCSEL as a light source of the line laser projection system, reduces interference between light emitting points of each VCSEL by utilizing the area array VCSEL, weakens laser speckles inside a line, and improves the quality of the projected line; meanwhile, an additional speckle dispersing device is not added in the system, the structure is simple, the cost is low, and the volume can be made very small.

Drawings

The technical scheme of the utility model is further explained by combining the attached drawings as follows:

fig. 1 is a YZ plane schematic diagram of a VCSEL-wordline laser projection system according to the present invention in a right-hand helical rectangular coordinate system;

fig. 2 is an XZ plane schematic diagram of a VCSEL-wordline laser projection system in a right-hand helical rectangular coordinate system according to the present invention;

wherein: 1. an area array VCSEL; 2. a word line lens; 3. a receiving screen; 2a, an even aspheric surface; 2b, even order aspheric cylinder surface.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Fig. 1 and 2 show a VCSEL-wordline laser projection system according to the present invention, which includes an area array VCSEL1, a wordline lens 2 and a receiving screen 3; the light emitting point arrays of the area array VCSEL1 are distributed in a long strip shape, the width direction of the area array VCSEL1 is in a YZ plane in a rectangular coordinate system, and the length direction of the area array VCSEL1 is in an XZ plane; the front surface of the word line lens 2 is a rotationally symmetric even aspheric surface 2 a; the back surface of the word line lens 2 is an even aspheric cylinder surface 2 b; the generatrix of the even aspheric cylindrical surface 2b is positioned in an XZ plane in a rectangular coordinate system, and the stretching direction is consistent with the length direction of the area array VCSEL1 luminous point array along the Y direction; when the planar array VCSEL1 is used, light beams emitted by each light emitting point of the planar array VCSEL1 are collimated by the rotationally symmetric even aspheric surface 2a, then are stretched and homogenized in the length direction of the light emitting point array by the even aspheric cylindrical surface 2b, the light transmission direction in a YZ plane is unchanged, and finally a word line laser is projected on the receiving screen 3.

The utility model discloses regard area array VCSEL1 as the light source of a word line laser projection system, utilize area array VCSEL1 in order to reduce the interference nature between every VCSEL light-emitting point, weaken the laser speckle in the word line inside, improve the quality of the word line that throws out; meanwhile, an additional speckle dispersing device is not added in the system, the structure is simple, the cost is low, and the volume can be made very small.

The above is only a specific application example of the present invention, and does not constitute any limitation to the protection scope of the present invention. All the technical solutions formed by equivalent transformation or equivalent replacement fall within the protection scope of the present invention.

Claims

1. A VCSEL-wordline laser projection system, characterized by: the array type laser comprises an area array VCSEL, a word line lens and a receiving screen; the width direction of the area array VCSEL is in a YZ plane in a rectangular coordinate system, and the length direction of the area array VCSEL is in an XZ plane; the front surface of the word line lens is a rotationally symmetric even-order aspheric surface; the back surface of the word line lens is an even order aspheric cylindrical surface; the generatrix of the even aspheric cylindrical surface is in an XZ plane in a rectangular coordinate system, and the stretching direction is along the Y direction; after light beams emitted by each light emitting point of the area array VCSEL are collimated by a rotationally symmetric even aspheric surface, the light beams are stretched and homogenized in the length direction of the light emitting point array through an even aspheric cylindrical surface, the light transmission direction in a YZ plane is unchanged, and finally a word line laser is projected on a receiving screen.

2. A VCSEL-wordline laser projection system according to claim 1, wherein: and the bus of the even-order aspheric cylindrical surface is consistent with the length direction of the area array VCSEL light emitting point array.