Laser resonator, has emission angle range set by focussing characteristics of optical system

摘要

The angular ranges of the laser resonator are limited in the desired emission direction(s) by the focussing characteristics, i.e. the local non-idealness of the optical system. At least one emission direction does not pass along the optical axis of the active material. At least one emission direction may not pass along the axis of symmetry of the resonator. Apertures or diaphragms are not used. An adjustable angle selection may be provided by the spherical aberration of a lens and/or mirror by varying the spacing to the laser material.