Regulation Of Scattered Light Fields And Analysis Of Their Characteristics

When light propagates in a scattering medium,it will be disturbed and scattered to all directions around,making focusing and imaging through the scattering medium extremely difficult.However,recent studies have shown that the information of light waves is not lost during the scattering process.For the same scattering medium,the definite input always corresponds to the definite output.In this way,it is possible to overcome or even utilize the scattering effect of the scattering medium to realize the control of the scattered light field.In this paper,starting from the theory of light wave transmission in scattering media,several types of technologies for focusing and image reconstruction through scattering media are studied.This paper first studies the measurement of the optical transmission matrix of the scattering medium.The distribution of the singular values of the measured transmission matrices is analyzed to prove that it follows the random matrix theory.The focusing ability of the pseudoinverse operator and the phase conjugate operator is analyzed,and is verified by experiments.Next,in this paper,we study the scattering media focusing techniques based on feedback-based wavefront shaping without transmission matrix measurement.Numerical simulations and experiments are performed to analyze the focusing effect of the feedback-based wavefront shaping focusing techniques based on the stepwise sequential algorithm,genetic algorithm and particle swarm algorithm.Then,a feedback-based wavefront shaping focusing technique based on memetic algorithm is proposed,which combines global search and local search,and solves the input phase required for focusing by simulating the co-evolution process of genes and culture.Numerical simulations and experiments are performed to prove the superiority of this method over genetic algorithm and particle swarm algorithm.Finally,in this paper,we study the image reconstruction techniques based on phase-shifting interferometry and pr VBEM respectively,numerical simulations are used to analyze their performance in various noise environments,and their effectiveness is verified through experiments.