Modeling Of MEMS Lidar Optical Transceiver System

The main research content of this article is to solve its solidification problem in the context of laser three-dimensional imaging radar: placing the MEMS micromirror inside the catadioptric panoramic optical system,the MEMS micromirror spiral panoramic scanning,rotating to achieve a 360-degree horizontal field of view The number of turns achieves a vertical field of view above 20 degrees.Based on the above situation,the system modeling design of the MEMS lidar optical antenna is used to meet the requirements of panoramic imaging.The main research content of this article is the optical antenna part of the lidar system,which is mainly explained from the following aspects:(1)Introduce two kinds of laser radar optical antenna transceiver methods:transceiver optical antenna and transceiver optical antenna.And the advantages and disadvantages of the two systems are compared and analyzed,and finally the method of sending and receiving is determined.The optical scanning technology was compared and analyzed,and finally the MEMS micromirror scanning method was determined to be low-cost,miniaturized,and high-precision,meeting the requirements of the lidar panoramic imaging system.(2)An overall analysis of the single-viewpoint catadioptric panoramic imaging system and the non-single-point catadioptric panoramic imaging system is carried out,including the design principles of the single-viewpoint catadioptric panoramic imaging system and the non-single-point catadioptric panoramic imaging system and the constraints here The design of the reflective surface under the conditions,that is,the design of the reflective mirror without distortion of the horizontal scene.(3)System modeling and simulation of MEMS lidar optical transceiver antenna.First,design a polarization optical isolation switch suitable for this system,and effectively isolate the transmitted signal and the received signal through the optical isolation switch.Secondly,a separate variable mapping method is proposed to establish the variable correspondence between the luminous energy of the light source and the illuminance distribution of the target plane.The three-dimensional configuration method of the microstrip surface is used to calculate the point coordinates and normal vectors on the surface to generate a three-dimensional free surface.And use Zernike polynomial to optimize the design of freeform surface.Finally,Zemax is used to simulate the free-form surface optical design.The designed catadioptric optical system can realize horizontal beam exit,and cooperate with MEMS spiral scanning to achieve 360° panoramic panoramic imaging.Byobserving the point diagram and calculating the divergence angle,it is found to meet the design index requirements.(4)MEMS galvanometer driving mode and scanning trajectory modeling.The experiment of MEMS galvanometer characteristic detection was carried out.By controlling the driving voltage and driving frequency of MEMS galvanometer,the rotation angle of MEMS galvanometer can be controlled,and then the desired scanning curve can be obtained.Research and experiment on the MEMS scanning trajectory,and finally select the spiral scanning curve.Furthermore,the problem of matching the spiral scanning parameters with the resonance frequency of the MEMS micromirror was studied,and the system was modeled.