Share Email Print
cover

Proceedings Paper

Holographic analysis of photopolymers
Author(s): Amy C. Sullivan; Marvin D. Alim; David J. Glugla; Robert R. McLeod
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Two-beam holographic exposure and subsequent monitoring of the time-dependent first-order Bragg diffraction is a common method for investigating the refractive index response of holographic photopolymers for a range of input writing conditions. The experimental set up is straightforward, and Kogelnik’s well-known coupled wave theory (CWT)[1] can be used to separate measurements of the change in index of refraction (Δn) and the thickness of transmission and reflection holograms. However, CWT assumes that the hologram is written and read out with a plane wave and that the hologram is uniform in both the transverse and depth dimensions, assumptions that are rarely valid in practical holographic testing. The effect of deviations from these assumptions on the measured thickness and Δn become more pronounced for over-modulated exposures. As commercial and research polymers reach refractive index modulations on the order of 10-2, even relatively thin (< 20 μm thick) transmission volume holograms become overmodulated. Peak Δn measurements for material analysis must be carefully evaluated in this regime. We present a study of the effects of the finite Gaussian write and read beams on the CWT analysis of photopolymer materials and discuss what intuition this can give us about the effect other non-uniformities, such as mechanical stresses and significant absorption of the write beam, will have on the analysis of the maximum attainable refractive index in a material system. We use this analysis to study a model high Δn two-stage photopolymer holographic material using both transmission and reflection holograms.

Paper Details

Date Published: 15 May 2017
PDF: 8 pages
Proc. SPIE 10233, Holography: Advances and Modern Trends V, 102330B (15 May 2017); doi: 10.1117/12.2265865
Show Author Affiliations
Amy C. Sullivan, Univ. of Colorado Boulder (United States)
Marvin D. Alim, Univ. of Colorado Boulder (United States)
David J. Glugla, Univ. of Colorado Boulder (United States)
Robert R. McLeod, Univ. of Colorado Boulder (United States)


Published in SPIE Proceedings Vol. 10233:
Holography: Advances and Modern Trends V
Miroslav Hrabovský; John T. Sheridan; Antonio Fimia, Editor(s)

© SPIE. Terms of Use
Back to Top