New approach to Rayleigh guide beacons

Michael Lloyd-Hart; Stuart M. Jefferies; E. Keith Hege; James Roger P. Angel

doi:10.1117/12.390334

7 July 2000 New approach to Rayleigh guide beacons

Michael Lloyd-Hart, Stuart M. Jefferies, E. Keith Hege, James Roger P. Angel

Proceedings Volume 4007, Adaptive Optical Systems Technology; (2000) https://doi.org/10.1117/12.390334
Event: Astronomical Telescopes and Instrumentation, 2000, Munich, Germany

Abstract

We present analysis and numerical simulations of a new method to sense atmospheric wavefront distortion in real time with Rayleigh beacons. Multiple range-gated images of a single pulse from the laser are used to determine each phase map, providing an advantage over other methods in that photon noise is substantially reduced for a given brightness of the beacon. A laser at about 350 nm projects collimated pulses of light adjacent to the telescope. Rayleigh-scattered light from each pulse is recorded through the full telescope aperture in a sequence of video frames, each a few microseconds long. Images are captured as the pulse approaches and passes through the height at which the camera is focused. Phase diversity is thus naturally introduced between the frames. An iterative algorithm is used to extract the pupil-plane phases from the recorded intensity distributions. We anticipate that such beacons are likely to be valuable in future advanced systems for adaptive optics on very large telescopes with multiple laser beacons and deformable mirrors that aim to provide a large corrected field of view by tomography of the atmospheric turbulence.

Citation Download Citation

Michael Lloyd-Hart, Stuart M. Jefferies, E. Keith Hege, and James Roger P. Angel "New approach to Rayleigh guide beacons", Proc. SPIE 4007, Adaptive Optical Systems Technology, (7 July 2000); https://doi.org/10.1117/12.390334

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available