Damage constraints in the design of high energy lasers for fusion applications

The design of large glass lasers for fusion applications is strongly influenced by considerations of the laser induced damage of optical materials. The laser requirements are reviewed. Damage phenomena in laser glass, thin film coatings, and other optical elements are discussed. The feedback problems arising from target reflection are considered. The principal causes of laser damage include self-focusing in the laser glass, damage at dielectric surfaces, and thin film damage. The theory and phenomenology of these processes is discussed. Possible future developments which will reduce or circumvent damage problems are proposed.