Related papers: The ALFA Laser: Beam Relay and Control System
The optimal performance of adaptive optics systems can only be maintained if the wavefront reference is bright and compact. Experience has shown that both of these important criteria are remarkably difficult to achieve with laser guide…
The sodium laser guide star adaptive optics system ALFA has been constructed at the Calar Alto 3.5-m telescope. Following the first detection of the laser beacon on the wavefront sensor in 1997 the system is now being optimized for best…
When scientific experiments require transmission of powerful laser or radio beams through the atmosphere the Federal Aviation Administration (FAA) requires that precautions be taken to avoid inadvertent illumination of aircraft. Here we…
The sodium laser guide star adaptive optics system ALFA, which is installed at the Calar Alto 3.5-m telescope, has been undergoing an intensive optimisation phase. Observations using natural guide stars that are presented in this paper,…
Laser guide stars with adaptive optics allow astronomical image correction in the absence of a natural guide star. Single guide star systems with a star created in the earth's sodium layer can be used to correct the wavefront in the near…
We present a beam steering system based on micro-electromechanical systems technology that features high speed steering of multiple laser beams over a broad wavelength range. By utilizing high speed micromirrors with a broadband metallic…
The importance of laser guide stars to the practical usefulness of adaptive optics cannot be understated, and yet there are very few working systems. This contribution discusses the current status of the ALFA laser guide star, with regard…
In the present paper, we consider the optical design of a zoom system for the active refocusing in laser guide star wavefront sensors. The system is designed according to the specifications coming from the Extremely Large Telescope…
We have developed and tested a novel method, based on LIDAR, of measuring the height and profile of the mesospheric sodium layer using a continuous wave laser. It is more efficient than classical LIDAR as the laser is on for 50% of the…
Precision wavefront control on future segmented-aperture space telescopes presents significant challenges, particularly in the context of high-contrast exoplanet direct imaging. We present a new wavefront control architecture that…
The Allen Telescope Array is a multi-user instrument and will perform simultaneous radio astronomy and radio SETI (search for extra-terrestrial intelligence) observations. It is a multi-beam instrument, with 16 independently steerable…
We present an inline optical device consisting of four optical components that produce a laser field consisting of two sub-beams where one is radially polarized and the other is linearly polarized. In the focus, the radially polarized…
A free-space laser communication system has been designed and partially developed as an alternative to standard RF links from UAV to ground stations. This project belongs to the SINTONIA program (acronym in Spanish for low…
The Max-Planck institutes for astronomy (MPIA) and for extraterrestrial physics (MPE) run an adaptive optics (AO) system with a laser guide star at the 3.5 m telescope on Calar Alto, Spain. This system, called ALFA, produces now scientific…
The ALEPH Silicon Vertex Detector features an optical fibre laser system to monitor its mechanical stability. The operating principle and the general performance of the laser system are described. The experience obtained during 1997 and…
We have created a new autonomous laser-guide-star adaptive-optics (AO) instrument on the 60-inch (1.5-m) telescope at Palomar Observatory called Robo-AO. The instrument enables diffraction-limited resolution observing in the visible and…
Traditional wavefront control in high-energy, high-intensity laser systems usually lacks real-time capability, failing to address dynamic aberrations. This limits experimental accuracy due to shot-to-shot fluctuations and necessitates long…
Adaptive optics to correct current telescopes over wide fields, or future very large telescopes over even narrow fields, will require real-time wavefront measurements made with a constellation of laser beacons. Here we report the first such…
Laser guide star systems based on Rayleigh scattering require some means to deal with the flash of low altitude laser light that follows immediately after each laser pulse. These systems also need a fast shutter to isolate the high altitude…
The spaceborne laser emission telescope is a core and critical component of the space gravitational wave detection system.Compared with ground-based telescopes, the on-orbit space environment is more complex and harsh, presenting higher…