Measurement of the Mueller matrix for phytoplankton1

Measurement of the light-scattering Mueller matrix of phytoplankton cultures resulted in a characteristic Mueller matrix much like that of seawater. Voss and Fry (1984) measured the scattering of polarized light by ocean water. We here report measurements of various phytoplankton cultures made to further our understanding of the ocean water measurements. To quantify changes in polarization due to scattering one must be able to describe the polarization and the transformations that take place. A convenient representation of ’ This work has been supported by the Office of Naval Research through contract NO00 14-80-C-O 113 and by the Texas A&M University Center for Energy and Mineral Resources contract 18789. the polarization of a light beam is the Stokes vector (van de Hulst 198 1). The four elements of this vector, labeled I, Q, U, and V, are defined in terms of the electric field as Z = Et + Er2, U = 2E,E,cos ii, Q = Et Er2, V = 2E,E,sin 6 where EI and E,, the components of the total electric field, and 6, the relative phase, are defined by E = El cos(kz wt + e,)f + E,cos(kz wt + e,)i,