Simultaneous dual-wavelength reflection digital holography applied to the study of the porous coal samples.
We present a simultaneous dual-wavelength phase-imaging digital holographic technique demonstrated on porous coal samples. The use of two wavelengths enables us to increase the axial range at which the unambiguous phase imaging can be performed, but also increases the noise. We employ a noise reduction "fine map" algorithm, which uses the two-wavelength phase map as a guide to correct a single-wavelength phase image. Then, the resulting noise of a fine map is reduced to the level of single-wavelength noise. A comparison to software unwrapping is also presented. A simple way of correcting a curvature mismatch between the reference and the object beams is offered.
Department of Physics, University of South Florida, Tampa, Florida 33620, USA. akhmalad@mail.usf.edu
Alexander
A
Khmaladze
Alejandro
A
Restrepo-Martínez
Myung
M
Kim
Roman
R
Castañeda
Astrid
A
Blandón