To develop the next generation of high-power, low-distortion optical amplifiers for space missions

 

Previously, a high power low optical distortion amplifier breadboard was developed and tested. It met all the performance requirements (similar to Aeolus booster amplifier), achieving 400+ mj at 100 Hz with an electrical to optical efficiency twice that of the Aeolus amplifier design.

 

Additionally, the thin disk technology tackled the key issue of thermal effects performance variation, allowing a truly low distortion high stability system. The thin disk technology enabled warm up time from switch off to emit of 4 s, demonstrating short term and long term stability far superior than existing designs.

 

It is vital to support the maturing of this technology for space application, in order to draft the path for future Lidar missions.

 

This activity shall focus on three elements:

• The multizone mirror, that is a critical component of this amplifier. The previous designs indicated issues with damage, once the amplifier operated at 100 Hz despite maintaining low fluence on previously measured high LIDT coating from DLR test facility. In order to improve the coating and the design of this mirror, first an analysis shall take place to understand the cause of its failure and improve the masking operation currently used and probably drives the reduction of the LIDT for these IBS hard coatings. Upon development of these novel coatings, an endurance campaign shall verify their prolonged performance suitability.

• The second element of this activity shall be the performance improvement of the larger disks OPD. Maintaining low intra-instrument fluence, customize the disk design architecture, in order to better control the optical distortions introduced by them and reduce the astigmatism of the amplifier beam. A single element breadboard with this larger disk shall be developed to verify performance.

• The production of the CAD drawings of an elegant breadboard design of this amplifier, with a thorough analysis of the thermal and mechanical constrains, taking into consideration the locations of maximum heat deposition. Complete CAD drawings of a single unit amplifier layout shall be produced maintaining previous high performance achieved.