Simple broadband implementation of a phase contrast wavefront sensor for adaptive optics
Year: 2004
Type: article
Abstract: The most critical element of an adaptive optics system is its wavefront sensor, which must measure the closed-loop difference between the corrected wavefront and an ideal template at high speed, in real time, over a dense sampling of the pupil. Most high-order systems have used Shack-Hartmann wavefront sensors, but a novel approach based on Zernike's phase contrast principle appears promising. In this paper we discuss a simple way to achromatize such a phase contrast wavefront sensor, using the pi/2 phase difference between reflected and transmitted rays in a thin, symmetric beam splitter. We further model the response at a range of wavelengths to show that the required transverse dimension of the focalplane phase-shifting spot, nominally lambda/D, may not be very sensitive to wavelength, and so in practice additional optics to introduce wavelengthdependent transverse magnification achromatizing this spot diameter may not be required. A very simple broadband implementation of the phase contrast wavefront sensor results.
Source: Optics Express
Authors: E. E. Bloemhof, J. K. Wallace
Institutions: California Institute of Technology, Jet Propulsion Laboratory
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
Funder: Jet Propulsion Laboratory
OpenAlex ID: W2107326148