Interference microscope objectives for wide-field areal surface topography measurements

Abstract

Abstract. We propose a type of interference objective that extends the range of application for flexible microscope platforms to larger fields of view. The objective comprises a beamsplitter plate and a partially transparent reference mirror arranged coaxially with the objective lens system. The coaxial plates are slightly tilted to direct unwanted reflections outside of the imaging pupil aperture, providing high fringe contrast with spatially extended white-light illumination. Examples include a turret-mountable 1.4× magnification objective parfocal with highmagnification objectives up to 100× and a dovetail mount 0.5× objective with a 34 × 34 mm field. This design is a practical alternative to the classical Michelson and Mirau type objectives for low magnifications. © The Authors.Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

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