![Ellipsometer](https://d27wgn5g4t3wja.cloudfront.net/img/471ddabc-babb-e76f-6730-ff0e4a90a5f2/152319.png)
Ellipsometer
Ellipsometer is optical instruments which measure the change in polarization
state of light beam upon reflection from a sample surface to analyze
the film thickness, the optical constants as the refractive index / absorption,
or the optical constants of bulk materials.