ph6b00199_si_002.mp4 (2.19 MB)
Tyndall Windows: Tunable Scattering of Disordered Solid–Liquid Matching Mixtures
media
posted on 2016-05-23, 12:20 authored by Benedikt Groever, Barmak Heshmat, Ramesh RaskarWe explain and explore
sharp optical diffusion modulations of solid–liquid
matching mixtures. The technique is based on sole refractive index
modulation mismatch of optically matching materials at different states.
This enables basic materials such as glass-based mixtures to obtain
a sharp window of transparency at a desired condition. Our demonstration
indicates over 3 orders of magnitude optical transmission modulation
with 0.03 thermally induced modulation of the refractive index mismatch.
The narrow full width at half maximum of this diffusion modulation
is the result of Tyndall scattering of densely packed irregular particles
that is not fully explainable by Mie theory. Such mixtures can be
used as tunable phantoms and have applications in optofluidics, rheology,
and cytometry.