Sensor of back-scattered light polarization in body cells

摘要

The biological tissues consist of cells which dimensions are bigger than a wavelength of visible light. Therefore a Mie scattering of transmitted and reflected light occurs and different polarization states arise. The back-scattered polarized laser light exhibits multiple scattering from the surface and subsurface layers of the sample. Notwithstanding this phenomenon is different if the cellular tissues are live or dead. In the case of porcine meat, there are temporal and dynamic changes not only as a result of chemical process, but also geometric deformations due to the water evaporation from intracellular and extracellular sites. Although multiple scattering in tissue randomizes incident polarization states, the shift of polarization can be clearly observed in diffusive scattering pattern due to the muscle orientation and meat aging. Accordingly, these temporal changes due to the multiple scattering of backscattered light allow measure the freshness of processed meat.