Polarized optical scattering signatures from biological materials

The polarization of laser light backscattered from biological samples has been measured over the wavelength range 350-850 nm. Incident circular, linearly polarized, and unpolarized light produces significant spectral features in the case of samples containing chlorophyll such as leaves and cyanobacteria. Polarization scattering signatures are observed around the chlorophyll 'red edge' that may have diagnostic value in the search for life signatures from extrasolar planets.