Analysis of an array of micro lenses using Fourier-transform method
R Rajasekharan, C Bay, J Freeman, TD Wilkinson
IET OPTOELECTRONICS | INST ENGINEERING TECHNOLOGY-IET | Published : 2010
The authors present an enhanced Fourier-transform technique to recover the phase profile, and hence the surface topography of an array of micro lenses. The technique combines fringe analysis by the Fourier-transform method, fringe extrapolation to reduce errors at the boundaries and phase unwrapping by the energy minimisation algorithm. The technique is validated by both simulation and experiment and is useful even when the Fourier spectra of the interferograms are not separated completely. The technique is also helpful in the presence of background noise. © 2010 © The Institution of Engineering and Technology.
Awarded by Engineering and Physical Sciences Research Council
The authors thank Rick Chen and Haider Butt for their fruitful discussions. One of the authors, Ranjith specially thanks UK-India Education and Research Initiative (UKIERI) and Cambridge Commonwealth Trust (CCT) for giving funds to pursue PhD.