Polarimetric characterization of a monochromator to measure the spectral response of a pixelated polarization imager

Author(s): Erica Venkatesulu, Musaddeque A. Syed, Joseph A. Shaw

Abstract

Monochromators are frequently used in spectral calibrations of optical systems due to their ability to sweep a narrowband output across a wide range of wavelengths. However, monochromators tend to output light with a degree of linear polarization that can vary significantly as a function of wavelength. To use a monochromator to calibrate a polarization-sensitive imager, the monochromator output is often passed into an integrating sphere to convert the linearly polarized light into randomly polarized light. In this paper, we demonstrate the ability to obtain a spectral calibration of a division-of-focal-plane (DoFP) imager by assuming subpixels of a polarization super pixel have equal spectral responses. We also characterize the polarization of the output of a monochromator as a function of wavelength using both a DoFP imager and a wire-grid polarizer mounted on a precision rotation stage with an optical power meter.

Citation

Venkatesulu, E., Syed, M. A., & Shaw, J. A. (2021). Polarimetric characterization of a monochromator to measure the spectral response of a pixelated polarization imager. In F. Snik, M. K. Kupinski, & J. A. Shaw (Eds.), Polarization Science and Remote Sensing X (p. 18). SPIE. https://doi.org/10.1117/12.2594011