Duality safety/efficiency for laser directed energy weapon applications

Abstract

This article reports an experimental contribution to High Energy Laser (HEL) engagement in urban combat by considering two key aspects: safety risks for the population due to Ytterbium beam reflectivity on target and vulnerability performance on drone cell structures by comparing Ytterbium and Thulium laser source technologies. A first phase is dedicated to the development of a proprietary specific high-reflective diffusive Lambertian screen, capable of withstanding high-temperature loadings. Then, dynamic Bidirectional Reflectance Distribution Function (BRDF) trials are performed at the Vulnerability Test Facility (VTF), in Talence, France. A specific focus is brought to the effect of target degradation on reflectivity pattern and level. The effect of incident laser beam shape is investigated. Finally, the efficiency of two laser source wavelengths on the drilling of thermoplastics is presented. The targets of interest include miscellaneous UAV (mini-drones) envelop materials of various colors. Maturity of laser source technologies has reached a point where the emergence of Laser Directed Energy Weapons (LDEW) on various theatres of operations becomes a short-term reality. Various target types will be engaged and each of these targets may be defeated in a scalable way (hard-kill, soft-kill). In that respect, understanding the effects and risks of HEL on targets, here in urban environment, is crucial.