Simultaneous, remote, and interferometric measurement of thickness and group refractive index

Dominic F. Murphy; Donal A. Flavin

doi:10.1117/12.372947

9 December 1999 Simultaneous, remote, and interferometric measurement of thickness and group refractive index

Dominic F. Murphy, Donal A. Flavin

Proceedings Volume 3860, Fiber Optic Sensor Technology and Applications; (1999) https://doi.org/10.1117/12.372947
Event: Photonics East '99, 1999, Boston, MA, United States

Abstract

A low-coherence optical fiber interferometric technique for simultaneous measurement of geometric thickness and group refractive index of highly dispersive materials is described. The technique, immune to the dispersion-induced asymmetry of the low-coherence interferograms obtained, overcomes some of the drawbacks associated with recently reported low-coherence approaches to this simultaneous measurement. The technique uses the experimental configuration of a tandem interferometer with the samples to be characterized placed in an air-gap in one arm of the measurement interferometer. Dispersion- insensitive measurements of the group delay imbalances in the measurement interferometer are made using dispersive Fourier transform spectrometry (DFTS). Sample thickness and group refractive index are calculated from these group delays which are unambiguously determined from the optical frequency dependence of the measured phases of the interferograms. Thickness measurements accurate to within 1 micrometer and group index measurements accurate to within one part per thousand have been achieved for BK7 and fused-silica glass samples in the thickness range 2000 to 6000 micrometers.

Citation Download Citation

Dominic F. Murphy and Donal A. Flavin "Simultaneous, remote, and interferometric measurement of thickness and group refractive index", Proc. SPIE 3860, Fiber Optic Sensor Technology and Applications, (9 December 1999); https://doi.org/10.1117/12.372947

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available