Two researchers from optical metrology instrument provider Zygo Corp. are recipients of the 2016 Rudolf Kingslake Medal and Prize. A photograph and measured 3D image of a 150-mm diameter transmission pump display. Courtesy of Zygo. Peter de Groot and James Biegen are the authors of "Interference microscope objectives for wide-field areal surface topography measurements.” The award is presented annually to the most noteworthy original paper published in the journal Optical Engineering by SPIE, the international society for optics and photonics. The award will be presented at a banquet during SPIE Optics and Photonics in San Diego in August. The researchers proposed a type of low-magnification interference objective that extends the range of application for flexible microscope platforms to larger fields of view. "The objective comprises a beam splitter plate and a partially transparent reference mirror arranged coaxially with the objective lens system," said the researchers in their paper. "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." De Groot is the executive director of R&D at Zygo. His research focuses on optical metrology for form, texture, part dimensions and position. He has published more than 140 technical papers, tutorials and book chapters in the fields of physics, interferometry, stage motion measurement and international metrology standards. His research has led to 130 U.S. patents for optical instruments. He is a SPIE Fellow and active contributor in the optics community. Biegen is a senior technical staff member at Zygo, specializing in the optical design of advanced metrology instrumentation. His interests range from laser Fizeau interferometry to interference microscopy, covering the complete product development cycle from applied research to manufacturing engineering. His contributions include physical optics modeling and the invention of high-precision interference objectives for both laser and white-light illumination. His work is highlighted in multiple U.S. patents and peer-reviewed journal articles. SPIE is the international society for optics and photonics, an educational not-for-profit organization that aims to advance light-based science, engineering and technology.