Stray-light correction in magnetograph observations using the maximum entropy method

We have developed a method of stray-light correction which is applicable to filter-based magnetograph observations. Stray-light-corrected Stokes image s are obtained by performing the deconvolution of observed Stokes images by the point spread function which is determined from the Stokes I image. For image deconvolution, the maximum entropy principle is used to guarantee th at intensity should be positive and polarization degrees should be less tha n unity. We present an iterative algorithm for the maximum entropy method, which seeks the solution in Fourier space and thus accomplishes fast conver gence. We find that our method is effective in correcting stray light which has a spread angle greater than the full width at half maximum of the poin t spread function. We also discuss the effect of stray light on magnetograp h calibration.