We present first results of Hertz/VPM, the first submillimeter polarimeter employing the dual Variable-delay Polarization Modulator (dual-VPM). This device differs from previously used polarization modulators in that it operates in translation, rather than mechanical rotation. We discuss the basic theory behind this device and its potential advantages over the commonly used half-wave plate. The dual-VPM was tested both at the Submillimeter Telescope Observatory and in the laboratory. In each case we present a detailed description of the setup. We discovered that properties of the VPM wire grids (diameter and spacing) caused behavior that differs from theoretical predictions for ideal wire grid performance. By modifying the polarimeter settings to compensate for this behavior, we found that the dual-VPM system is robust, operating with high efficiency and low instrumental polarization. This device is well suited for air- and space-borne applications.
© 2008 Optical Society of America
Optical Design and Fabrication
Original Manuscript: March 26, 2008
Revised Manuscript: July 17, 2008
Manuscript Accepted: July 17, 2008
Published: August 19, 2008
Megan Krejny, David Chuss, Christian Drouet d'Aubigny, Dathon Golish, Martin Houde, Howard Hui, Craig Kulesa, Robert F. Loewenstein, S. Harvey Moseley, Giles Novak, George Voellmer, Chris Walker, and Ed Wollack, "The Hertz/VPM polarimeter: design and first light observations," Appl. Opt. 47, 4429-4440 (2008)