High Power, Thermally Optimized Blue Laser for Lidar

To enable widespread and rapid airborne bathymetric lidar to adequate depths in many ocean regions a low-cost, rugged, and high energy pulsed laser source must be developed in the ocean water transmittance spectrum of 450 - 490 nm. The ideal laser source will be high performance for lidar (high pulse energy, high rep rate, short pulse duration) with specific targeted emission spectrum to meet ocean water transmittance and filtering requirements. It will also feature low SWaP and a rugged form factor with high reliability for continual use on mobile platforms. No existing laser source can meet these demanding requirements. To address this challenge and meet NASA's lidar source needs, Bridger Photonics, Inc. (Bridger) proposes creating a high power Q-switched, off-line Nd:YAG source at 946 nm, which, when frequency doubled to 473 nm, will provide high transmittance through ocean waters. Bridger's design will leverage three key innovations proven out in its Phase I effort: efficient, end-pumped, low-quantum-defect architecture; gain crystal design for optimal heat removal; and robust monolithic, alignment-free fabrication. The proposed design would allow for widespread deployment of mobile ocean-penetrating lidar transmitters. Successful completion of this Phase II effort will allow Bridger to demonstrate >10 W of average blue power in a compact, turn-key package. Bridger has modeled and constructed similar lasers through SBIR efforts previously and will apply the innovations developed there towards this new system for NASA.