Propagation of polarized light through liver, muscle and skin was studied using the Mueller Matrix formalism. Collimated HeNe laser light was passed through a set of polarization elements to create one of four possible polarization states (horizontal (H), vertical (V) and 45- degree (P) orientations of linearly polarized light, and right circularly (R) polarized light). The beam passed through thin sections of tissue of varying thickness (0.2- 0.9 mm thick). The unscattered, collimated, transmitted light passed through a second set of polarization elements to analyze for transmission of each of the 4 possible polarization states (H,V,P,R). Transmitted intensities for 16 possible combinations of source and detector polarization yielded a data matrix that was converted into a Mueller matrix describing the propagation properties of the tissue. The results were roughly consistent with all three tissue types behaving as ideal retarders whose birefringent values, dn = (Delta) *wavelength/(2*(pi) *thickness), were in the range of 1x10-3 to 5x10-3 which is consistent with the literature. The order of the strength of birefringence was liver < muscle < skin. Although the above birefringence values may apply to muscle, the structure of liver and skin are not necessarily consistent with the ideal retarder model and further work is needed.
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