Research On Single Photon Compressive Spectral Imaging Based On Joint Modulation Of Dual-DMD

Single photon compressive spectral imaging combines single pixel imaging with spectral measurement technology,which realizes the compression and acquisition of spectral images.As a new type of spectral imaging scheme,single photon compressive spectral imaging can obtain the spatial information and spectral information of the imaging object simultaneously.Compared with the traditional spectral imaging technology,single photon compressive spectral imaging can reduce the sampling time and the amount of data acquisition of signals and improve the signal-to-noise ratio of imaging system.The spectral imaging system cannot provide the multi-point spectral information of the object in space simultaneously at present.Generally,it needs to obtain the spectral data by using the repeated measurement of the filter component band,which leads to the large amount of data acquisition,and seriously affects the stability of the optical system.In this context,this paper focuses on single photon compressive spectral imaging.The main research contents and achievements are as follows:(1)We have established a single photon compressive spectral imaging system by using digital micromirror device(DMD)as spatial light modulator and using parallel single photon source,reflective diffraction grating and high-precision count Photomultiplier Tube(PMT).According to the functional requirements of the system,the synchronous control and photon counting circuit based on Field-Programmable Gate Array(FPGA)and the host computer control software system are designed and implemented independently.(2)The theoretical analysis and technical research of the imaging system are carried out,and the algorithm verification of the single photon compressive spectral imaging scheme is completed.The sampling model of single photon compressive spectral imaging system is established,and the imaging system is simulated by Monte Carlo method.Through the simulation results and the system imaging experiment,the spatial information and spectral information of the imaging target can be measured simultaneously.(3)In a single pixel imaging system,the measurement matrix is related to the optical signal modulation and image reconstruction,which has a great impact on the performance of the imaging system.The binary matrix loaded onto the digital micro-mirror device(DMD)for optical modulation,that is,each pixel can only be modulated into on-off states.In order to improve the performance of measurement matrix,we propose a digital grayscale modulation method,and construct random measurement matrices with gray level through matrix transformation of different schemes.Combined with the sampling method of DMD grayscale modulation,a higher quality gray image can be reconstructed.