Measurement of angular distributions by use of low-coherence interferometry for light-scattering spectroscopy

We present a novel interferometer for measuring angular distributions of ba ckscattered light. The new system exploits a low-coherence source in a modi fied Michelson interferometer to provide depth resolution, as in optical co herence tomography, but includes an imaging system that permits the angle o f the reference field to be varied in the detector plane by simple translat ion of an optical element. We employ this system to examine the angular dis tribution of light scattered by polystyrene microspheres. The measured data Indicate that size information can be recovered from angular-scattering di stributions and that the coherence length of the source influences the appl icability of Mie theory. (C) 2001 Optical Society of America.