Tool for analyzing a polarization state of a light beam

Abstract

An apparatus is provided for analyzing the polarization state a light beam. A rotatable disk provides, on a surface of the disk, a visual indicator and a centrally positioned polarizer. The indicator and polarizer rotate with the disk as a single unit. A drive motor is engaged with the rotatable disk for providing motive force in rotating the disk about its central rotational axis. A signal processing circuit includes an optical detector positioned on one side of the polarizer for receiving the light beam after the light beam passes through the polarizer. The optical detector produces a detector electrical signal of an amplitude generally dependent on the instantaneous rotational position of the rotatable disk, as such position is determinant of the light attenuating power of the polarizer on the light beam. The signal drives the visual indicator to produce a visual image as the disk rotates. The image is dependent on the signal amplitude and the polarization state of the light beam, whereby the polarization state is determinable from the image. Additional components are included for determining the four Stokes polarization vectors, and differentiating between unpolarized and circularly polarized light.

Dependencies are inferred from the claim text.