State of Light Polarization

phase difference

component of electric field

x

y

This Demonstration allows you to visualize elliptical, linear, or circular state of light polarization. For a transverse electromagnetic wave propagating in the

z

direction, any polarization state can be expressed in terms of linear polarizations along the

x

and

y

directions, which are transverse to the direction of propagation. To visualize a state of polarization, vary the

x

or

y

components of the electric field (i.e., polarization), and/or the phase difference between the two—that is, the phase of the

x

component relative to the

y

component. The direction of electric field rotation (for elliptical and circular polarization) is coded using the visible part of the electromagnetic spectrum: red → yellow → green → blue → violet.