Laser speckle projector based on vertical cavity surface emitting laser VCSEL regular lattice

Abstract

The invention provides a laser speckle projector based on a vertical cavity surface emitting laser VCSEL regular lattice. The laser speckle projector comprises a VCSEL regular light emitting lattice,a collimating mirror, an optical diffraction device, an X-Y direction driving circuit and a lattice display control module, by driving different light emitting particles on the VCSEL regular light emitting lattice, multiple frames of different encoding patterns are output in a time sharing manner, thereby realizing the space-time marking of a target object or a projection space, and finally the three-dimensional depth measurement of the target object is completed through a depth decoding algorithm. Compared with the traditional structured light space encoding technology, the projector providedby the invention is conducive to achieving space-time encoding, so that higher precision, robustness and anti-interference ability can be obtained in the process of depth decoding for three-dimensional depth measurement.

Description

technical field [0001] The invention relates to the technical fields of computer vision, depth perception and laser imaging, in particular to a laser speckle projector based on a vertical cavity surface emitting laser (VCSEL) regular lattice. Background technique [0002] Depth perception technology is used to perceive the shape and distance information of space objects, and is a hot research and application development direction in the field of computer vision. The active vision depth perception technology based on structured light can obtain the depth information of the image more accurately. Compared with the binocular stereo camera, the obtained depth map information is more stable and reliable, not affected by ambient light, the stereo matching process is simple, and the algorithm calculation amount is high. Small and other advantages. Among them, the laser speckle projector is one of the key devices of the structured light depth perception technology, and the projecte...

AI Technical Summary

Problems solved by technology

[0004] The structure of the laser speckle projector mainly includes a light source, a collimating mirror and / or a diffractive optical device DOE (Diffractive Optical Element). There are problems such as large volume, low photoelectric conversion efficiency, and large influence of temperature drift; some laser speckle projectors are arranged in irregular random VCSEL lattices to project basic code patterns, which are projected after duplication by diffractive optical devices DOE , the dot matrix arrangement is a random light-emitting dot matrix, which has problems such as insufficient accuracy of the dot matrix arrangement position, limited dot matrix production density, and low production yield. Moreover, the random light-emitting dot matrix is ​​used as the basic coding pattern. When copied and spliced ​​by DOE, the pattern It is easy to overlap or be too sparse between the edge lattices, resulting in a large gap between the final laser speckle coding pattern and the designed coding pattern

In addition, the speckle coding patterns projected by existing laser speckle projectors are basically fixed and are used for spatial coding of target objects or projected spaces, and are greatly affected by ambient light in the process of structured light depth perception. , which is not conducive to improving the depth measurement accuracy and robustness

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