Title

Speckle Mitigation for Wavefront Sensing in the Presence of Weak Turbulence

Document Type

Article

Publication Date

2019

Abstract

When measuring atmospheric turbulence along the propagation path to an extended non-cooperative target, a wavefront sensor normally suffers from severe noise due to speckle. In this work, we quantify the benefits of speckle mitigation via polychromatic illumination for a Shack–Hartmann wavefront sensor. We obtain results over a wide range of conditions by using the spectral-slicing approach to polychromatic wave-optics simulations. To quantify speckle noise, even when turbulence is present, we introduce a metric involving racetrack-mode strength in slope-discrepancy space. The results show that polychromatic illumination greatly reduces speckle noise under realistic conditions. Even with near worst-case conditions, 15 coherence lengths per resolution cell reduce the wavefront-measurement error by 56%.

Comments

The "Link to Full Text" button on this page loads the open access article version of record, hosted at OSA. The publisher retains permissions to re-use and distribute this article. © 2019 Optical Society of America

DOI

10.1364/AO.58.002300

Source Publication

Applied Optics

Share

COinS