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arXiv · 1606.02774

Inexpensive LED-based spectrophotometer for analyzing optical coatings

Kayla Hardie·Sascha Agne·Katanya B. Kuntz·Thomas Jennewein
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Abstract

Optical coatings are widespread in everyday life, from camera lenses to glasses, to complex optics experiments. A simple, reliable device that can quickly and inexpensively analyze optical coatings is a valuable laboratory tool. Such a device can identify unknown or mislabelled optics, and characterize the transmission spectra of optical elements used in an experiment. We present the design and characterization of a LED-based spectrophotometer, and demonstrate its ability to identify different optical coatings. Our approach uses ten LEDs that cover a spectrum from 365 nm to 1000 nm. A small servomotor and microcontroller rotates a LED board to sequentially position each LED over an optical sample, and the transmitted light corresponding to each LED is measured with a silicon photodetector. The device is automated, portable, inexpensive, user-friendly and simple to build.

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Kayla Hardie, Sascha Agne, Katanya B. Kuntz, Thomas Jennewein. 2016-06-08. Inexpensive LED-based spectrophotometer for analyzing optical coatings. https://arxiv.org/abs/1606.02774

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