Thickness measurement of transparent plates by a self-mixing interferometer.
We introduce a technique to measure transparent glass slab thickness. It employs a very simple setup combining two interferometers: a forward-going beam scheme and a self-mixing readout of the beam reflected back to the laser source. Interestingly, the difference of the two readouts provides a quantity related to thickness measurement, irrespective of refractive index. We demonstrate this method using samples on a range of thickness from 30 to 1000microm.
Fathi
Mohammad Taghi
MT
Dipartimento di Elettronica, Università degli Studi di Pavia, 27100 Pavia, Italy. mohammad.fathi@unipv.it
Donati
Silvano
S