Study On The Wavefront Detection Technique Of Optical Two-dimensional Negative Feedback System

The two-dimensional optical negative feedback system makes use of the concept ofone-dimensional negative feedback in the electrical system, it is an innovative attemptwhich extends one-dimensional negative feedback to two-dimensional negativefeedback. The two-dimensional optical negative feedback system is realized inall-optical way, there is no device to cut off the light, it gets the true sense of opticalclosed-loop system. The optical information processing technology has the advantagesof two-dimensional parallel, the drawback of traditional electronic systems in theprocessing speed of the technical barriers is overcomed, it has a very important meaningand value to the study of modern signal processing. Wavefront sensing technology is thekey technology of adaptive optics. It is conducive to the realization of two-dimensionaloptical negative feedback phase control system in two-dimensional optical negativefeedback system. A detailed theoretical analysis of wavefront sensing technology iscarried in this thesis. Considering about the need of two-dimensional optical negativefeedback system, the most appropriate wavefront detector was chosen. In order toreslize the two-dimensional optical feedback system, The wavefront sensing technologyis analyzed and simulated in a targeted manner, and some valuable conclusions areobtained.The main work of the thesis are as follows:①Three wavefront sensing technologies: shearing interferometer wavefrontsensing technology, Shack-Hartmann wavefront sensing technology and curvature of thewavefront sensing technology are enumerated. Combined with the two-dimensionaloptical negative feedback system wavefront sensing requirements, a suitable wavefrontsensing technology for two-dimensional optical negative feedback system is selected.②A Shack-Hartmann wavefront sensor is analyzed. its working principle and dataprocessing is discussed, and the algorithm in Shack Hartmann sensor is discribed.Various mathematical models and simulation of Shack Hartmann are established indifferent reconstruction mode.③The factors, which affect the Shack-Hartmann wavefront sensor’s detectionaccuracy are analyzed. Combined with the current study, the impact of the wavelengthon the Shack Hartmann wavefront sensor is analyzed and simulated.④Proposed a two-dimensional optical negative feedback system closed-loop phase correction system model and its theoretical simulationThe innovations of the thesis are as follows:①Put forward a new using method of closed-loop phase correction systemcomposed of wavefront sensor and phase corrector.②A model of closed loop phase correction system composed of ShackHartmann wavefront sensor and pure phase spatial light modulator is proposed. It isapplied to the two-dimensional optical negative feedback system, making thetwo-dimensional optical feedback system to realize pure optical negative feedback.