基于数字高频检相式的激光测距光学系统设计

为了改善相位差法激光测距测量精度低的现状,采用高频检相法代替模拟测相法,即数字高频检相式的激光测距光学系统来提高测距精度。实现了10MHz的激光调制频率,设计了准直透镜,给出了设计指标,利用ZEMAX软件对光束准直前后进行了对比分析,并通过实验验证了光学系统设计的可行性。结果表明,标准差最大为0.12°,重复距离精度可约达1mm,误差最大为0.09°,最小为0.011°,说明测量的重复性比较好、稳定度高,满足了精度要求,达到了提高精度的目的。

Optical design of a laser distance measuring system based on high frequency digital phase detection

In order to improve the precision of phase-shift measurement,a kind of high frequency phase method,laser distance measuring system based on high frequency digital detection,was used to improve the measurement precision instead of the analog phase measurement.10MHz laser modulation frequency and the design of digital phase detector were achieved.The collimator lens was designed and the design specifications was listed.Comparative analysis was made before and after beam collimation with ZEMAX.The feasibility of the optical system was verified by the experiments.The maximum standard deviation is 0.12°,and the distance precision can be improved to about 1mm.In addition,the maximum error is 0.09°,while the minimum is 0.011°.These resucts show that the system meets the requirement of accuracy and achieves the purpose of improving the accuracy.