Simple general analysis of the polarization-dependent insertion loss of a linear optical system

Abstract

A simple general analysis of the insertion loss (diffraction efficiency, or gain) of a linear, deterministic or non-deterministic, optical system as a function of the state of polarization of incident quasi-monochromatic light is presented using the Stokes vector-Mueller matrix description and the associated geometrical interpretation in the Poincare sphere space. A scalar and a vector differential insertion loss (DIL) are defined that determine the intensity transmittance of the optical system for the unpolarized and totally polarized components of an incident partially polarized light beam, respectively. The insertion loss is maximum and minimum when the incident light is totally polarized in a pair of orthogonal states along the straightline extension of the DIL vector, and is constant for all states in a plane normal to the DIL vector, on and within the circle of intersection of the plane with the Poincare sphere. Finally, some results are presented of the measured components of the DIL vectors of a grating that diffracts light into several orders.