학술논문

Properties of a Variable-delay Polarization Modulator
Document Type
Working Paper
Source
Applied Optics, vol. 51, Iss. 2, pp. 197-208 (2012)
Subject
Astrophysics - Instrumentation and Methods for Astrophysics
Language
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 microns 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.
Comment: 25 pages, 10 figures, accepted by Applied Optics