| As one of the important branches of the proximity fuze,laser fuze has the advantages of strong anti-interference ability and high-ranging accuracy.Laser imaging fuze is one of the important development directions of laser fuze,which can realize accurate target recognition.The traditional laser imaging system has a complex structure and is difficult to assemble,which makes it difficult to achieve mass production.In addition,the transmission and reception modules added to obtain high-density point clouds will increase the volume,cost,and power consumption.Focusing on the requirements of miniaturization and all solid state of laser imaging fuze,this paper proposes the design scheme of the transmitting module of the laser imaging system based on MEMS mirror and proposes a method to dynamically adjust the number of wire harnesses,that is,the density of point clouds,according to specific conditions.Firstly,the relationship between the key parameters of the MEMS mirror(resonant frequency,scanning angle,mirror size)is determined,and the performance of the MEMS mirror is described in detail by the quality factor(Fo M value),from which the model of MEMS mirror is selected.Then,according to the selected MEMS mirror parameters and the spot size,after the optical system is collimated,the type selection of the pulse laser and the design of the pulse laser driver circuit is carried out.According to the specific laser and MEMS mirror,the optical system of emission collimation is designed.Zemax optical simulation software is used for simulation to determine the parameters of the collimating lens of the optical system so that the divergence angle of the beam emitted by the pulse laser can meet the use requirements.Finally,FPGA is used as the control module to dynamically adjust the repetition rate of the pulse laser emitted by the laser by changing the size of the MEMS mirror pulse interval angle,so that the two can work together and finally achieve the goal of real-time control of the number of harnesses,that is,the point cloud density can be dynamically adjusted to meet different user requirements.Based on the design scheme of the transmitting module of the laser imaging system based on the MEMS mirror,an experimental platform is built,which does not include the FPGA module.The volume of the entire transmitting module is 5.5 cm × 2.5 cm × 2.8cm,basically meeting the requirements of miniaturization.In addition,the experimental results show that the change in the number of harnesses is feasible,which shows that the point cloud density can be dynamically adjusted,and the module is solid. |
