Highly Sensitive Imaging Studies Based On Coding Measurements

Under the conditions of low light and high noise,conventional imaging methods have poor image quality and can not even tell the target object in the image.This paper starts with changing the imaging method,high sensitivity imaging based on encoding measurement is studied.The encoding measurement imaging is a method of encoding and modulation of optical signal and multi-channel detection technology,it encodes and modulates the optical signals of multiple pixels by encoding components to combined measurements,and then reconstructs the actual scene image.The research in this paper mainly focuses on the encoding algorithm and the system implementation.Encoding algorithm is the choice of encoding matrix.The traditional Hadamard cyclic S-matrix coding has been used in the Hadamard transform spectrometer,but the improvement of signal-to-noise ratio is not good enough.in this paper,three new encoding algorithms are proposed,which are complementary S matrix,full Hadamard matrix,and maximum luminous flux matrix.The complementary S matrix encoding is a double-matrix encoding algorithm based on cyclic S-matrix coding,it reduces the noise such as stray light and dark current by subtracting the encoding result of two matrices;Full Hadamard matrix coding is a coding algorithm that uses two-matrix coding to implement the theoretical optimal matrix Hadamard matrix;The maximum luminous flux matrix coding imaging is to enable the detector to maximize the luminous flux,thereby enhancing the signal to noise ratio of a coding algorithm.the theoretical denoising analysis and imaging simulations of these algorithms are carried out,the results show that the proposed algorithms can effectively improve the signal-to-noise ratio and improve the image quality.For system implementation,firstly,the two problems of focusing light and low loss of light are solved and the optical path system is built up;secondly,We use DMD and its control system for encoding optical signal,the signal is processed by amplifier and filter,the program with labview controls the data acquisition box to acquire the signal,the image is reconstructed by Matlab,and so on.Lastly,the encoding algorithm proposed above is experimentally verified on the experimental system based on encoding measurement.The experimental results are in accordance with the expected requirements.