A phase laser ranging system and method

Abstract

The embodiment of the invention provides a phase laser ranging system and method. The system comprises a laser emitting unit, a first lens and a phase ranging unit. The laser emitting unit comprises alaser light source and a second lens. The center of the first lens and the center of the second lens are separated by a predetermined distance. The phase ranging unit comprises a number of phase ranging subunits. A number of phase ranging subunits are arranged on the focal plane of the first lens in an array. The measurement range of each phase ranging subunit is smaller than the phase ambiguitydistance of the system. The phase ranging unit is used to acquire the distance between an object to be measured and the laser emitting unit according to the phase difference between a second laser anda first laser and the measurement range of each phase ranging subunit. The laser emitting unit simply needs to emit a laser once to complete ranging, which improves or even eliminates the problem ofphase ambiguity.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of laser ranging, and more specifically, to a phase laser ranging system and method. Background technique [0002] Common laser ranging methods include triangulation and time of flight (TOF), wherein the time of flight method is further divided into pulse method and phase method. Both the triangulation method and the phase ranging method are relatively low in cost, but each has its own weakness: the accuracy of the triangulation method drops rapidly when the measurement distance is relatively long, and generally can only be used within a short distance; while the phase method has the problem of phase ambiguity , the higher the ranging frequency, the higher the accuracy, but the shorter the distance where phase ambiguity occurs, it is often necessary to use multiple frequency lasers to eliminate phase ambiguity and obtain relatively high accuracy through multiple measurements, which will...

AI Technical Summary

Problems solved by technology

Both the triangulation method and the phase ranging method are relatively low in cost, but each has its own weakness: the accuracy of the triangulation method drops rapidly when the measurement distance is relatively long, and generally it can only be used within a short distance; while the phase method has the problem of phase ambiguity , the higher the ranging frequency, the higher the accuracy, but the shorter the distance where phase ambiguity occurs, it is often necessary to use multiple frequency lasers to eliminate phase ambiguity and obtain relatively high accuracy through multiple measurements, which will lead to phase The time for ranging becomes longer, which is acceptable for ordinary single-point ranging, but when it is rotated to form a 2D or 3D lidar, it will cause low resolution and motion blur problems

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