Laser-mode engineering by generalized resonator concepts

Allowing arbitrary profiles for the mirrors of laser resonators offer a wide range of design freedom for the optimization of lasers. This is not only restricted to modifications of the output beam shape but can be widely used to change the mode characteristic inside the cavity and thus, the behavior of the complete laser system. However, the different kinds of lasers require strongly different design methods for the resonators. Whereas well known and straight forward design algorithms exist for stable resonator types other lasers such as unstable ones or waveguide lasers require much more elaborated designs.