title: Depth-resolved wavefront aberrations using a coherence-gated Shack-Hartmann wavefront sensor.
abstract: In the present paper we investigate the possibility of narrowing the depth range of a physical Shack - Hartmann (SH) wavefront sensor (WFS) by using coherence gating. For the coherence gating, two low coherence interferometry (LCI) methods are evaluated and proof of principle configurations demonstrated: (i) a time domain LCI method based on phase shifting interferometry and (ii) a spectral domain LCI method, based on tuning a narrow band optical source. The two configurations are used to demonstrate each, the possibility of constructing a coherence gated (CG) SH/WFS. It is shown that these configurations produce spot patterns similar to those provided by a conventional SH/WFS. The two proof of principle configurations are also used to illustrate elimination of stray reflections in the interface optics which normally disturb the operation of conventional SH/WFSs. The speed and noise performance of the two CG-SH/WFS implementations are discussed.
authors.affiliation: Applied Optics Group, School of Physical Sciences, University of Kent, CT2 7NH Canterbury, UK. simontuohy@gmail.com
authors.forename: Simon
authors.initials: S
authors.lastname: Tuohy
authors.forename: Adrian Gh
authors.initials: AG
authors.lastname: Podoleanu
mesh_terms: D019781:Corneal Topography / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D041623:Tomography, Optical Coherence / Q000295:instrumentation*; D014159:Transducers