One form of the present invention is a dual channel optical reflectometer
composed of a birefringent path coupler and an optical source path that is
optically connected to the path coupler. After entering the path coupler,
light is split into birefringent reference and sample paths. The reference
path is optically aligned with a first collimating lens, and the
collimating lens is directed into a scanning delay line. There is also a
birefringent optical sample path that is also optically connected to the
path coupler. The sample path is optically aligned with a polarization
channel separator/combiner and a lens, to focus and direct optical beams
into the turbid sample. Light backscattered from the turbid sample is
collected by the second lens and orthogonal polarization channels are
reunited by the polarization channel combiner. An analog-to-digital
converter is connected to the amplifier, and a computer is connected to
the analog-to-digital converter to analyze the output.