Measurement Of Laser Spot Parameters For Laser Oblique Transmission

Beam quality is a very important parameter in evaluating the laser system.The accurate measurement of the space-time distribution of the laser far field to the target power density is an important means to calculate the drift of the laser center of mass,the quality of the beam and other important parameters.It is also of great significance to the analysis of the atmospheric transmission effect of the laser and the evaluation of the beam control ability of the laser system and the tracking and pointing ability.The work done in this paper is divided into three parts.In the first part,the scheme of measuring the laser beam spot parameters is determined mainly,and a variety of methods used to detect the parameters of laser spot are introduced.Based on the specific experimental environment and requirements of this experiment,we choose to use CCD to capture the spot image and attitude control to simulate the airborne environment.The way to carry out the system design.In the second part,the hardware structure and circuit part of the system are designed.DSPIC33FJ16MC304 is selected as the main control chip of the control module.The step motor is used to adjust the attitude and the target surface is rotated.At the same time,the stepping motor drive circuit is designed,the beacon lamp driver and the switch control circuit are designed,and the optoelectronic design is designed.Detector conversion and data acquisition circuit;design serial communication circuit to complete data communication with industrial control computer and adjust each module according to the real-time data of industrial computer;industrial computer is connected with CDD camera,power meter and wireless transmission module;the third part carries out the number of spot images.According to the processing,the image filtering,the image filtering part,this paper analyzes the cause of the noise generation of the spot image.According to the cause of the noise,the different filtering algorithms are designed,and the effects of each filtering algorithm on the post spot centroid are analyzed,and the results and complexity of the algorithm are integrated.Degree,through many experiments and analysis,we find a method that can effectively remove the noise of the spot and can have less influence on the post spot centroid.In this paper,three different centroid extraction methods are analyzed,and the algorithm complexity,capacity and accuracy of each algorithm are analyzed,and the experiment is finally proved.The center of gravity method has better effect on the spot spot detection,and it can meet the needs of the research content in accuracy and algorithm complexity.At the end of this paper,the circuits and algorithms designed before are verified.The images collected by 500 meters are demonstrated and analyzed.The images are processed in a series of processing.Finally,all the parameters of the spot are obtained and the control of the target board is completed.The applicability and effectiveness of the hardware are verified.