Research On Laser Detection And Measurement Technology Based On Four Quadrants

As the progress of science and technology and the development of national defense,laser probing has been widely used in many different fields,such as laser guidance,workpiece straightness measurement,solar tracking and so on.Taking laser detection application as the research background,this paper designs a set of laser detection and measurement system based on the four-quadrant.In this paper,we focus on the system hardware circuit design and improvement of the positioning algorithm.After comparing the performance and scope of three kinds of detectors and analyzing the performance of the four quadrant detector in detail,the four quadrant detector is finally selected as the photoelectric converter of this system.The effect of the light spot size on the location of the spot center has been analyzed and used as a theoretical framework for the design of.The design and simulations of different analog amplifier circuits lay a solid foundation for the gain control and pulse extraction.The hardware circuit of power module,self gain amplifying module,signal acquisition and processing module(FPGA)are designed and debugged,which provide a reliable hardware platform.After analyzing the process and influence factors of light and electrical signal,the system finally adopts the signal processing mode of self gain amplification and pulse extraction.Comparing four kinds of spot location algorithms,it is concluded that the traditional addition and subtraction algorithm have acceptable performance and wider application range.The interference of dark current and noise in the detector and circuit,the interference of background light,the non-uniformity interference of detector and circuit,the interference of other light sources and the mechanical error can account for detection error of the system.After analysis of the above interference and mathematical modeling,the correction and calibration methods are developed.Finally,a complete set of laser detection and measurement experimental system based on the four quadrant is established,the function of the detection system,the location algorithm,the feasibility of the correction and calibration method have been verified by experiments.