Simulation Platform Of Hartmann Wavefront Sensor

Adaptive optics (AO) systems are widely applied for the real-time atmosphericturbulence disturbances correction of the ground-based telescopes. Shark-HartmannWavefront Sensor is generally used for wavefront detection, and the WavefrontController is the controlling center in AO systems. The randomness of environments,such as the atmospheric turbulence and the noises, increases the difficulty of thewavefront processor algorithm verification. So, we design the simulation platform ofHartman Wavefront Sensor instead of the actual test platform. It can provide thereal-time images for the wavefront processor, shorten the development period, andpropose a convenient solution for algorithm verification.Firstly, the principle of Hartmann wavefront sensor is introduced, including theprinciple of formation image with optics lens, the Zernike polynomials expression ofwavefront aberration and noise analysis, etc. In this basis, an explicit explain of theimage requirements, the amount of calculation, and the real-time analysis arerepresented. Then, PC software and FPGA hardware Co-design is settled down andthe system is divided into several parts. One focus of the study is the simulation ofHartman images using MATLAB and Visual C++, meanwhile, it can communicatewith FPGA via Ethernet. The other one is the FPGA hardware to achieve thefollowing functions:(1) receive image data from PC;(2)cache by DDR2SDRAM;(3)in the transmitting mode, outputting the data in accordance with the timing of theCCD camera through the Camera Link interface. Finally, the test of the simulationimages and the hardware are carried on. The results show that the principle and theapproach of the simulation are correct.The study with a combination of hardware and software implements thesimulation of Hartman Wavefront Sensor. The software programming can flexiblyconfigure the parameters of the system, and easy to maintain and upgrade. Thehardware can reduce the processing time. It can meet the demands of the largecomputational capacity and high output rate.