Some aspects of polarizer performance

Null polarimetry near shot noise limit at 1 Hz

We describe the principle and report on the realization of a null polarimeter with two demonstrated features: (1) the sensitivity of the system is near shot noise limit and (2) quasi-stationary signals at 1 Hz can be measured without signal modulation. The achieved single-pass sensitivity is 7 × 10(-9) rad/Hz with a pair of Glan-Taylor polarizers, which should be of great interest for experiments such as observation of vacuum magnetic birefringence and search for new particles. The system is brought near its shot noise limit by appropriate polarization control and coherent heterodyne detection of light, resulting in a sensitivity improvement by two orders of magnitude in comparison with the case of no control on light polarization.

Imaging Characteristics of the Itek PROM

This paper discusses advances in the fabrication, operation, and performance of the Itek PROM (Pockels readout optical modulator). Devices of high optical quality have been made and evaluated. Measurements of MTF and sensitivity under various conditions are presented. Stored images can be enhanced in contrast by a change in device voltage and the same method used to suppress the zero order in Fraunhofer diffraction patterns of such images. The results of this technique are demonstrated.