Non-linear Fresnelet approximation for interference term suppression in digital holography
Journal
Proceedings of SPIE - The International Society for Optical Engineering
Journal Volume
5207
Journal Issue
2
Date Issued
2003-01-01
Author(s)
Abstract
We present a zero-order and twin image elimination algorithm for digital Fresnel holograms that were acquired in an off-axis geometry. These interference terms arise when the digital hologram is reconstructed and corrupt the result. Our algorithm is based on the Fresnelet transform, a wavelet-like transform that uses basis functions tailor-made for digital holography. We show that in the Fresnelet domain, the coefficients associated to the interference terms are separated both spatially and with respect to the frequency bands. We propose a method to suppress them by selectively thresholding the Fresnelet coefficients. Unlike other methods that operate in the Fourier domain and affect the whole spacial domain, our method operates locally in both space and frequency, allowing for a more targeted processing.
Subjects
B-splines | Digital holography | Fresnel transform | Fresnelets | Interference | Non-linear approximation
Type
conference paper