Open AccessSimultaneous thickness and group index measurement with a single arm low-coherence interferometer
Author(s) -
Sérgio Carlos Zílio
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.027392
Subject(s) - interferometry , optics , refractive index , coherence (philosophical gambling strategy) , materials science , measure (data warehouse) , optical coherence tomography , borosilicate glass , physics , quantum mechanics , database , computer science , composite material
We present a single arm low-coherence interferometer to directly measure the physical thickness and group refractive index of optically transparent samples having flat and parallel surfaces. The optical arrangement, resembling a common-path interferometer, is more compact and stable than the usual dual-arm low-coherence interferometer. It has been used to measure samples of Herasil 102 fused silica, Schott B270 Superwhite crown glass and borosilicate cover glass. The results obtained indicate uncertainties in the third decimal place for index values and thicknesses accurate to within 2 μm.