Dynamically refocused Rayleigh laser beacons for atmospheric tomography

Michael Lloyd-Hart, James Georges, Roger Angel, Guido Brusa, Patrick Young

Research output: Contribution to journalConference articlepeer-review

16 Scopus citations


We report initial results from a prototype system to generate multiple Rayleigh laser guide stars for adaptive optics from a single pulse laser at 354 nm wavelength. A 3.2 mW laser pulsed at 630 Hz was used to project three beams on the sky simultaneously, each pulsed at 210 Hz. A spinning mirror was used to direct the pulses in three directions at the vertices of an equilateral triangle 90 arcsec across. Laser pulses were triggered by a synchronising electrical pulse from the motor. Dynamic focusing optics in the receiving telescope will in future be used to hold such beacons from more powerful lasers in focus over a height range of many kilometers. Multiple beacons can be used to derive tomographic information on the vertical distribution of the aberration. We show initial analytical and numerical work on how the unique features of refocused Rayleigh beacons can improve the tomographic wavefront measurement for multi-conjugate adaptive optics.

Original languageEnglish (US)
Pages (from-to)259-270
Number of pages12
JournalProceedings of SPIE - The International Society for Optical Engineering
StatePublished - 2002
EventAdaptive Optic Systems and Technologies II - San Diego, CA, United States
Duration: Jul 30 2001Aug 1 2001


  • Laser guide stars
  • Multi-conjugate adaptive optics
  • Rayleigh beacons
  • Tomography

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Dynamically refocused Rayleigh laser beacons for atmospheric tomography'. Together they form a unique fingerprint.

Cite this