Research On Performance Of Single Pixel Imaging System Based On Full Chain Model

Single pixel imaging technology uses a single point detector and a space light modulator to modulate and sample the object,and combines measurement matrix and reconstruction algorithm to restore the object image.Researchers have made continuous improvements in device selection,measurement value processing,reconstruction algorithm design and other aspects,gradually improving the image quality and expanding the application range.In order to evaluate the performance of the single-pixel imaging system and assist the design and optimization of the optical path of the system,the whole chain model of the single-pixel imaging system was constructed by visualizing the influence factors such as aberration,defocus and jitter.The main research work of this paper is as follows:(1)According to the working principle of single-pixel imaging technology,the parameters that can evaluate the imaging quality and system performance are analyzed from the aspects of reconstructed image,reconstruction algorithm and system noise,and the imaging chain model is used to describe the optical path of the single-pixel imaging system.(2)A full chain model of single pixel imaging system based on imaging chain is proposed.For the optical devices in the system,the light path is divided into three parts: the lighting path for collimating the light source,the projection path for projecting the mask onto the object,and the detection path for collecting the light beam to the single point detector.The influence of aberration,defocus and other factors on image blur and deformation is analyzed.(3)Set different parameters of optical devices in the system for simulation.It is found that the illumination path has little effect on the imaging results.In the projected light path,the aberration coefficients increase gradually at intervals of 3-10 wavelengths,and the modulation transfer function of the system decreases from 0.9 to 0.5.The defocus amount of the photosensitive surface of the detector was set to 10% in the detection light path,and the image contrast decreased.The similarity and SNR of the pulse response and modulation function of the system with the image were compared.(4)A single pixel imaging system was designed and built,including the hardware equipment such as light source,projection part and detection part,as well as the selection of detection target,measurement matrix and reconstruction algorithm.The generalized single-pixel imaging experiment and single-pixel camera imaging experiment are respectively carried out.According to the evaluation function of imaging chain,the type of projection lens and the position of detector are changed,and the imaging similarity is increased from 0.1 to 0.5,indicating that the design of optical path of single-pixel imaging system can be effectively optimized by using this model.