Stokes parameters

Lore & Background

They provide a mathematically convenient alternative to describing incoherent or partially polarized radiation in terms of total intensity, fractional degree of polarization, and the shape parameters of the polarization ellipse.

Reader's Guide

The Stokes parameters are significant because they offer a complete and practical description of the polarization state of light, including partially polarized and unpolarized light, which is not easily handled by other methods. They are directly observable and can be used to calculate the effect of optical systems on light through Mueller calculus. The four parameters, often denoted I, Q, U, and V, correspond to total intensity and three components describing polarization. Their legacy is foundational in fields such as astronomy, remote sensing, and optics, enabling precise analysis of light from sources like stars and atmospheric particles. The parameters are constrained by the degree of polarization p, which ranges from 0 to 1, and the phase information of polarized light is not recorded in them.

Did You Know?

• The four Stokes parameters are sometimes denoted I, Q, U, and V.
• The Stokes parameters can be determined from directly observable phenomena.