GAIA contains two identical telescopes, pointing in two directions separated by a 106.5° basic angle and merged into a common path at the exit pupil. The optical path of both telescopes is composed of six reflectors, the last two of which are common. Both telescopes have an aperture of 1.45m × 0.5m and a focal length of 35m. The telescope elements are built around the hexagonal optical bench with a ~3m diameter, which provides the structural support (source: sci.esa.int).
Two Laser Diodes from German company eagleyard Photonics have been installed on GAIA, the European Space Agency's billion-star surveyor spacecraft. The single-frequency DFB-852 Laser Diodes in a 14-pin butterfly housing are responsible for keeping GAIA’s two telescopes in the right position so it can continue to create the most accurate 3D map of the Milky Way galaxy ever produced.
The DFB-852 Laser Diodes contain a wavelength-selective grating integrated in the laser chip. They operate on a single resonator mode emitting quasi-monochromatic radiation with a very small linewidth and low phase noise. The lasers harbour a very low-intensity noise due to the lack of mode partition noise (source: Electro Optics).
An extended qualification program has proven the quality of a previously evaluated semiconductor Laser Diode, which is intended to be used in a subsystem for the GAIA mission. We report on results of several reliability tests performed in subgroups. The requirements of the procurement specification with respect to reliability and desired manufacturing processes were confirmed. This is an example for successful collaboration between component supplier, system integrator and payload responsible party.
CATS - NASA Mission (2015)
The International Space Station (ISS) is an ideal platform to conduct many scientific research projects from the space, including the remote sensing of the Earth’s atmosphere. One [..] is the Cloud Aerosol Transport System (CATS). CATS is a lidar remote sensing instrument designed to provide measurements of atmospheric clouds and aerosol properties. It will continue the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) data record, provide observational lidar data to improve operational modeling programs, and demonstrate the direct lidar retrieval of aerosol extinction from space. (source: Fibertek)
Mission Duration: 0.5 - 3 years
Launched to the ISS in January 2015, CATS is specifically intended to demonstrate a low-cost, streamlined approach to developing ISS science payloads. The CATS mission extends the data record of space-based aerosol and cloud measurements to ensure the continuity of lidar climate observation.
MERLIN - DLR/CNES Mission (2021)
In 2021, the French-German MERLIN satellite (Methane Remote Sensing Lidar Mission) will go into Earth orbit to measure concentrations of atmospheric methane with unprecedented precision and thus better understand the sources of this greenhouse gas playing a key role in global warming (source: CNES)
Mission duration: 3 years
To accomplish this mission, MERLIN will be relying on its Methane Integrated Path Differential Absorption (IPDA) lidar, which will fire laser beams towards Earth’s surface and then analyse the signal bounced back to deduce the amount of methane in the sounded atmospheric column (source: CNES)
Laser diode developer eagleyard Photonics has been assigned by SpaceTech to deliver space-qualified distributed feedback (DFB) seed laser diodes for [the] Franco-German small satellite mission.
eagleyard Photonics is set to deliver the DFB seed laser diodes at 1064 and 1645nm for the whole program — as well as for the corresponding qualification campaign, including the second generation of engineering models in 2017, the qualification models and the flight models in 2018. SpaceTech is the responsible contractor for the frequency reference-unit of the lidar instrument of the entire mission program (source: Photonics Media)