Single-shot, simultaneous spatially resolved spectropolarimetry and wavefront sensing with stress engineered optics

Shack–Hartmann wavefront sensors have been important instruments in ophthalmology, astronomy, general metrology and laser beam characterization. We combine previous investigations of single shot/single frame spectropolarimetry and extend it to address the question whether one can separate the polarization and wavefront information contained in discrete spectral components. By combining a Shack–Hartmann sensor with a relay system having a stress-engineered optic in the pupil plane, we calibrate the system for polarization and wavefront gradient and use the resulting measurement matrix to separate polarization and wavefront gradient for three discrete wavelengths. The system is capable of measuring wavefront gradients of 100 μrad or smaller, with a typical angular error on the Poincaré sphere of 0.25 rad.