Raman fiber amplifier (RFA) based sodium Laser Guide Stars (LGS) are of great interest for adaptive optics systems in astronomical telescopes, optical ground stations and space debris tracking systems.
Based on MPBC's 40 W 1178 nm RFA system, these 22 W LGS at 589 nm have been deployed by all the major 8-10 m ground-based VIS/IR astronomical telescopes around the world. They have been widely acclaimed for their consistent high performance, low-maintenance, ease of use and reliability.
Recognizing the need for higher-power LGS for Optical Ground Stations (OGS) for laser satellite communications, we have scaled our systems to a record output power of 130 W, enabling LGS output powers over 50 W at 589 nm. This unprecedented power level unlocks the opportunity for daytime operation of adaptive optics.
In addition, MPBC's patented remote pump delivery technology facilitates integration by allowing separation up to 50 m between the electronics cabinet and laser head, which includes the RFA. These enhancements create opportunities for smaller telescopes and new applications.
RFA-based LGS offer enhanced performance, operational simplicity, reliability, and low maintenance compared to earlier LGS technologies (dye lasers and bulk optics solid-state lasers). In an RFA LGS, a narrow-band seed at 1178 nm is amplified in a single-mode optical fiber and then frequency doubled to 589 nm. MPBC has advanced narrow-band RFA technology, pioneered by ESO, to unprecedented power levels by overcoming the challenge of suppressing stimulated Brillouin scattering (SBS).
MPBC’s advanced RFA design also utilizes an all-polarization-maintaining (PM) fiber architecture. To power the RFA, a high-power Fiber Laser Pump Module (FLPM) based on two PM fiber lasers—at 1064 nm and 1120 nm—has been developed. This innovative two-laser setup also enables the option of utilizing MPBC's patented Remote Pump Delivery technology, separating the FLPM from the compact RFA for enhanced flexibility in deployment.
MPBC is constantly refining its LGS technologies, with a focus on scalability, suppressing SBS, and remote pump delivery. Our ongoing efforts to optimize efficiency, reduce costs, and explore new applications, will ensure that we remain at the forefront of this exciting industry.
