• Brian DuPraw

Advanced Coatings Lab

The Advanced Coatings Lab (ACL) is a part of the University of California Observatories (UCO). It was developed in response to a need for improved optical coatings for ground-based astronomy, in particular, silver-based reflective coatings for telescope mirrors and broad-band anti-reflection (AR) coatings for lenses, windows and prisms.

The ACL is headed by Dr. Andrew Phillips, and the lab technician is Brian DuPraw.

What are optical coatings?

Optical coatings are thin films applied to mirror and lens surfaces to enhance reflection (for mirrors) or suppress reflection (“anti-reflection” for lenses and other transmissive optics). They can consist of one or multiple layers of various materials, and are generally quite thin, perhaps 200-400 nm in thickness for visible-light coatings – this is roughly one half a wavelength of visible light, or1/300 the diameter of a human hair.

Note that the terms “thin films” and “coatings” are used interchangeably, although a coating can include multiple thin films.

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Dr. Andrew Phillips

Brian DuPraw