Effective Coherence Length Estimation of Optical Wavefronts

نویسندگان

  • Akondi Vyas
  • M B Roopashree
  • B R Prasad
چکیده

In adaptive optics, the measurement of spatial coherence length helps in deciding the optimum design parameters of a Shack Hartmann Sensor (SHS). Two methods of estimating the spatial coherence length of optical wavefronts are presented. The first method is based on counting the number of Hough peaks in the wavefront. The second method is based on a simple data mining technique applied on the wavefronts. Optical wavefronts with different properties are simulated and used for statistical analysis. A comparison of the performance of the two methods is presented using Monte Carlo simulations. It is shown that both these methods can become efficient tools in estimating the effective coherence length of optical wavefronts.

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تاریخ انتشار 2009