Development of Laser Transmitter for Earth Observation on Multi-sensing Observation Lidar and Imager

Abstract

The Multi-sensing Observation Lidar and Imager (MOLI) project, Japan's first spaceborne earth observation lidar, began in August 2024 as a JAXA research and development project. MOLI aims to demonstrate key lidar technologies in orbit and collect data for forest biomass assessment, 3D digital map accuracy improvement, and atmospheric analysis. The system features a high-peak power pulsed laser and a telescope to measure ground elevation and canopy height. Development efforts have focused on extending laser lifespan and ensuring environmental tolerance. Long-term vacuum chamber tests confirmed stable output, and vibration and thermal shock evaluations validated operational durability. The project also addresses laser-beam stability and precision pointing accuracy. This report presents the design, system configuration, and experimental results of laser components, which will contribute to future spaceborne lidar missions.