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arXiv · 2005.10437

Determining the refractive index, absolute thickness and local slope of a thin transparent film using multi-wavelength and multi-incident-angle interference

Mengfei He·Sidney R. Nagel
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Abstract

We describe a high-speed interferometric method, using multiple angles of incidence and multiple wavelengths, to measure the absolute thickness, tilt, the local angle between the surfaces, and the refractive index of a fluctuating transparent wedge. The method is well suited for biological, fluid and industrial applications.

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Mengfei He, Sidney R. Nagel. 2020-05-21. Determining the refractive index, absolute thickness and local slope of a thin transparent film using multi-wavelength and multi-incident-angle interference. https://doi.org/10.1364/oe.397736

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