Spinel optics for high energy lasers

Transparent magnesium aluminate spinel (MgAl₂O₄) ceramic has excellent transmission from the UV to mid-wave IR. It is rugged with strength that is 5x that of glass. Spinel is being developed as a sensor window for numerous military platforms. At the U.S. Naval Research Laboratory (NRL), we have focused on process developments to facilitate wider acceptance of spinel for various applications. These developments include purification of spinel to reduce the absorption and scattering losses for use as an exit aperture on High Energy Laser (HEL) systems and various cost-effective densification methods to reduce manufacturing costs. In this paper, we will provide an update on some of the ongoing spinel activities at NRL.