Share Email Print

Proceedings Paper

Measurement of refractive index of photopolymer for holographic gratings
Author(s): Eriko Watanabe; Jun Mizuno; Chiemi Fujikawa; Kashiko Kodate
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

We have made attempts to measure directly the small-scale variation of optical path lengths in photopolymer samples. For those with uniform thickness, the measured quantity is supposed to be proportional to the refractive index of the photopolymer. The system is based on a Mach-Zehnder interferometer using phase-locking technique and measures the change in optical path length during the sample is scanned across the optical axis. The spatial resolution is estimated to be 2&mgr;m, which is limited by the sample thickness. The path length resolution is estimated to be 6nm, which corresponds to the change in refractive index less than 10-3 for the sample of 10&mgr;m thick. The measurement results showed clearly that the refractive index of photopolymer is not simply proportional to the exposure energy, contrary to the conventional photosensitive materials such as silver halide emulsion and dichromated gelatine. They also revealed the refractive index fluctuation in uniformly exposed photopolymer sample, which explains the milky appearance that sometimes observed in thick samples.

Paper Details

Date Published: 20 February 2007
PDF: 9 pages
Proc. SPIE 6488, Practical Holography XXI: Materials and Applications, 64880A (20 February 2007); doi: 10.1117/12.714392
Show Author Affiliations
Eriko Watanabe, Japan Women's Univ. (Japan)
Jun Mizuno, Japan Women's Univ. (Japan)
Chiemi Fujikawa, Japan Women's Univ. (Japan)
Kashiko Kodate, Japan Women's Univ. (Japan)

Published in SPIE Proceedings Vol. 6488:
Practical Holography XXI: Materials and Applications
Roger A. Lessard; Hans I. Bjelkhagen, Editor(s)

© SPIE. Terms of Use
Back to Top