GLAS: launching Rayleigh lasers from the WHT

Paul Jolley; Tom Gregory

doi:10.1117/12.670789

28 June 2006 GLAS: launching Rayleigh lasers from the WHT

Paul Jolley, Tom Gregory

Proceedings Volume 6272, Advances in Adaptive Optics II; 62723P (2006) https://doi.org/10.1117/12.670789
Event: SPIE Astronomical Telescopes + Instrumentation, 2006, Orlando, Florida , United States

Abstract

The 4.2m William Herschel Telescope (WHT) at the Isaac Newton Group of Telescopes (ING) is due to have a new Rayleigh laser beacon installed. This will form part of the Ground-layer Laser Adaptive optic System (GLAS). GLAS will compliment the existing Nasmyth Adaptive Optic Multipurpose Instrument (NAOMI) currently in operation and allow for much greater sky coverage than before. A 30W laser will be launched from behind the secondary mirror of the WHT. To facilitate this, a support has been designed to mount the laser on the top end ring of the telescope. The mount is designed to give a gravity stable platform in a thermally stable environment. The mount required the use of astatic levers to help maintain alignment with the telescope. The laser beam is steered over the telescope vanes and into the Beam Launch Telescope (BLT) which is mounted behind the secondary mirror. The BLT then expands the beam and launches it to 20Km. Two wavefront sensors are used to correct the image. The laser guide star wavefront sensor (LGS WFS) uses a beamsplitter to pickoff the laser return at its wavelength. The existing NAOMI WFS is still used but is now the natural guide star wavefront sensor (NGS WFS) and corrects for tip/tilt. This paper will concentrate on describing the mechanical design and FEA of the laser up launch system (laser cradle and mount and the BLT). A very brief overview of the LGS WFS will be given for system completeness.

Citation Download Citation

Paul Jolley and Tom Gregory "GLAS: launching Rayleigh lasers from the WHT", Proc. SPIE 6272, Advances in Adaptive Optics II, 62723P (28 June 2006); https://doi.org/10.1117/12.670789

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