Gaussian filters for off-axis digital holography via angular spectrum method

Abstract

Effects of the spatial filter used in the reconstruction of off-axis digital holograms are investigated. Two kinds of Gaussian filters, multiplicative and cut-off filters, were explored and compared with an ideal band-pass filter of similar dimensions in the reconstruction of digital holograms through the use of the angular spectrum method. The multiplicative Gaussian filter multiplies a Gaussian function centered at the desired peak in the Fourier domain and the Gaussian cut-off filter removes signals greater than the corresponding value of a Gaussian function. It was shown that compared to using the ideal band-pass filter, the Gaussian multiplicative filter results to less artifacts and that the Gaussian cut-off filter results to better contrast in the reconstructed image.