title: Properties of a variable-delay polarization modulator.
abstract: We investigate the polarization modulation properties of a variable-delay polarization modulator (VPM). The VPM modulates polarization via a variable separation between a polarizing grid and a parallel mirror. We find that in the limit where the wavelength is much larger than the diameter of the metal wires that comprise the grid, the phase delay derived from the geometric separation between the mirror and the grid is sufficient to characterize the device. However, outside of this range, additional parameters describing the polarizing grid geometry must be included to fully characterize the modulator response. In this paper, we report test results of a VPM at wavelengths of 350 μm and 3 mm. Electromagnetic simulations of wire grid polarizers were performed and are summarized using a simple circuit model that incorporates the loss and polarization properties of the device.
authors.affiliation: Observational Cosmology Laboratory, Code 665, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA. David.T.Chuss@nasa.gov
authors.forename: David T
authors.initials: DT
authors.lastname: Chuss
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Wollack
authors.forename: Ross
authors.initials: R
authors.lastname: Henry
authors.forename: Howard
authors.initials: H
authors.lastname: Hui
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Juarez
authors.forename: Megan
authors.initials: M
authors.lastname: Krejny
authors.forename: S Harvey
authors.initials: SH
authors.lastname: Moseley
authors.forename: Giles
authors.initials: G
authors.lastname: Novak