Rayleigh Beacons & Dynamic Refocus

Video

This is two separate data sets, one with and one without Dynamic Refocus on. The left half of the movie is the "off" version, where you can see all five laser spots simultaneously. The cone shaped spots result from the limited depth of focus of the telescope combined with the off-axis position of the laser projector. The right half of the movie is the "on" version, where the limited depth of field of the telescope has been compensated for with a moving element. Each data set was taken at 30 fps with an image intensifier tube that was shuttered to only transmit light from 20 to 30 km altitude. The scale is the same for both images.

Download in Microsoft MPEG-4 Format (Requires Windows Media Player 9)
Download in DivX AVI Format (Requires Divx Player)
Download in Quicktime MPEG-4 (Requires Quicktime Player 6)

Publications

Design and Testing of a Dynamic Refocus System for Rayleigh Laser Beacons
(James A. Georges III, Proteep Mallik, Thomas Stalcup, J. Roger P. Angel, Roland Sarlot)
SPIE Proc. on Adaptive Optical System Technologies II, eds. Peter L. Wizinowich and Domenico Bonaccini, 4839, Kona, HI, 2002.

Dynamically Refocused Rayleigh Laser Beacons for Atmospheric Tomography
(Michael Lloyd-Hart, James Georges, Roger Angel, Guido Brusa, and Patrick Young)
Presented at SPIE 4494, Adaptive Optics Systems and Technology II, San Diego, CA, July 31, 2001.

Dynamics Refocus for Rayleigh Beams
(Roger Angel)
Science with the LBT, ed. Tom Herbst, Sponsored by the Max-Planck Society and the LBT Beteiligungsgesellschaft, Proceedings of a Workshop held at Ringberg Castle, Bavaria, July 2000, pp. 21-25.