MERLIN laser transmitter - Laser performance for critical mission objectives and outlook for future missions

The Methane Remote Sensing LiDAR Mission (MERLIN) is a Franco-German cooperation between the French Space Agency CNES and the German Space Agency at DLR.The Laser Optical Bench for the IPDA LiDAR instrument is currently being built at Fraunhofer Institute for Laser Technology, based in Aachen, Germany. The laser bench is one of the core parts of the payload, for which Airbus Defence and Space GmbH is the Prime Contractor. The laser and laser housing design were developed and optimized in close cooperation between Airbus Defence and Space GmbH and Fraunhofer Institute for Laser Technology.This presentation will provide an overview of the flight hardware’s assembly, integration and test status, the qualification status of all optical components and the lifetime test results for critical components. Furthermore, we will highlight the inherent stability aspects of the laser: for example, the demonstrated stable and full-performance operation of the oscillator and the amplifier over a wide range of thermal boundary conditions. Currently, the last optical stage of the laser, the pre-assembled and fully aligned optical Parametric Oscillator (OPO) is being integrated on the flight laser bench. The qualification module is already completely optically integrated. In the frame of the presentation, we will be showcasing current optical performance of the laser transmitter for flight and qualification module. Additionally, we will provide an outlook on future LiDAR laser concepts based on the developments within the MERLIN project.