Study On The Optical Implementation Of All-optical 2-D Negative Feedback System

All-optical two-dimensional negative feedback system extends one-dimensional electrical negative feedback to two-dimensional optical system,which takes advantages of high-speed parallel processing of optical system and stable output of electronic negative feedback system.It can overcome the shortcomings of traditional coherent optical system in image quality,system accuracy,processing speed,stability,antiinterference ability,and achieve ultra-high speed,high capacity,high precision and high stability of the information processing capabilities.Phase distortion correction,twodimensional parallel negative feedback superposition and optical image amplification are the key technologies of all-optical two-dimensional negative feedback system.In this thesis,the feedback and optical amplification of all-optical two-dimensional negative feedback system have been studied specifically.The corresponding basic theory,mathematical model were introduced and the system performance was analyzed in detail.Furthermore,the optical image amplification technology which is suitable for all-optical two-dimensional negative feedback system has been analyzed and studied via actual experiments,and the main factors that affect the image amplification have been obtained.The main contents of the paper include:1.Based on analysis of the key technologies of all-optical two-dimensional negative feedback system,and combined with the characteristics of the system,the optimal amplification method for the system has been chosen by comparing common image amplification technologies.2.The basic theory of all-optical two-dimensional negative feedback system was described in detail.The theories of diffraction and optical amplification based on two wave coupling were applied to the closed-loop system for the establishment of theoretical model.And then,according to the Fourier transform properties of lens,the ideal experimental conditions for the system were proposed,and the output performance of the system was analyzed by means of simulation.3.Based on theoretical analysis of two wave coupling optical amplification,the optical axis direction of crystal,the polarization state of incident beams,the irradiation order and incident angle of two incident beams were determined by corresponding physical experiments.4.Considering the experimental condition of two wave coupling optical image amplification and the existing experimental equipment,experiments were designed and an optical experimental platform was built,whereon the influence of different crystals,incident angles,incident light intensity and wavelength on image amplification were studied.The innovative points of the thesis lie in:1.Based on the theories of diffraction and two wave coupling optical amplification,the theoretical model of all-optical two-dimensional negative feedback system was established.The ideal experimental conditions of the system was obtained by applying the Fourier transform properties of convergent lens,and finally,the feasibility of closedloop system was verified through simulations.2.The theory of two wave coupling optical amplification was applied to twodimensional system.Furthermore,according the designed experiment scheme,an optical experiment platform was built.So various factors on optical image amplification were explored.