In this Letter, we introduce an algorithm that overcomes limitations in shape measurement by holographic microscopic methods in cases of micro-optical elements with high NA, such as microlenses. The presented algorithm provides a simple method for shape reconstruction from interferometrically measured phase. The algorithm is based on the analysis of local ray transition through the measured object. We develop algorithms for holographic configurations working in transmission and reflection. The accuracy of the developed algorithms is proved by experiments and extensive simulations. We present an experiment in a holographic Mach–Zehnder configuration where we have measured and successfully reconstructed the height distribution of spherical and cylindrical microlenses with NA up to 0.3.
© 2011 Optical Society of America
Original Manuscript: August 8, 2011
Revised Manuscript: September 28, 2011
Manuscript Accepted: October 3, 2011
Published: November 15, 2011
Vol. 7, Iss. 1 Virtual Journal for Biomedical Optics
Tomasz Kozacki, Michał Józwik, and Kamil Liżewski, "High-numerical-aperture microlens shape measurement with digital holographic microscopy," Opt. Lett. 36, 4419-4421 (2011)