Laser Parameter Detection Method For Automatic Noise Suppression Of Imaging Sensors

In the laser parameter detection system based on imaging sensors,there are inevitably multiple types of noise,which seriously affect the accuracy of parameter detection.In order to solve the above problems,a laser parameter detection method with noise automatic suppression is proposed.The specific research contents are as follows:(1)Analyze the sources of noise in the laser parameter detection system,establish a noise model of the imaging system based on the statistical characteristics of the imaging sensor noise,propose a laser energy automatic attenuation control model and an image noise automatic suppression laser parameter detection method.(2)A closed-loop laser energy automatic attenuation control system based on optimal gray scale range of the laser spot was studied.The optimal gray scale range was determined based on the photoelectric response characteristics of the imaging sensor and the noise model of the imaging system.The control system consists of an attenuation module and an exposure module.The attenuation module controls the number of incident photons,and the exposure module controls the pixel exposure time.The negative feedback function in the system adjusts the attenuation rate and exposure time to ensure that the maximum gray value of the laser spot satisfies the optimal gray scale range.(3)Research a parameter measurement algorithm for automatic image noise suppression based on bilateral threshold shrinkage iteration.The first threshold is calculated by statistically analyzing the background noise distribution,and the second threshold is determined using the Otsu method.The integration area of the spot image is initialized by bilateral thresholding,and an objective function is designed to iteratively shrink the integration area to determine the laser beam width.The laser parameters are then obtained by fitting a hyperbola.A laser parameter measurement system was built to detect laser parameters using the measurement method proposed in this paper and traditional measurement methods,and compared with the results of the M~2-200S detection to evaluate its accuracy.The experimental results show that the laser energy control system improves the laser beam width detection accuracy by 9.21%compared with the traditional dimming method,and the noise automatic suppression parameter measurement method improves the laser beam width detection accuracy by 7.62%compared with the traditional edge fitting method.The relative error of the laser parameters(beam width,beam divergence angle,beam waist width,M~2factor)proposed in this paper is less than 3%.The measurement method proposed in this paper can fully characterize the laser properties,improve the accuracy of laser beam parameter measurement,and is of great significance for the in-depth application of laser technology.