Handbook of Biomedical Optics

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30.1 Introduction

e more common imaging modalities rely on absorption of

photons, scattering of photons, or regeneration of new photons

at new wavelengths (uorescence, Raman scattering). But a pho-

ton also has an orientation of the vibration of its electric eld that

characterizes the photon. When a population of photons share a

common orientation of their electric elds, the light is described

as polarized. Polarized light is commonly encountered in pola-

roid glasses with vertically oriented linear polarization lters to

block the horizontally vibrating photons that skip o the surface

of a road or water surface. Hence, the glass ...