Patent ID: 6137821
Filing Date: 2000-10-24
Classification: G03F,H01S

Abstract:
A durable etalon output coupler for an ultraviolet laser designed to produce a laser beam within a desired wavelength range, said output coupler comprising:an etalon comprised of:1) a first prism defining a first inside surface and a beam entrance surface and being comprised of a material transparent to ultraviolet light within said desired wavelength range and defining an index of refraction n.sub.m1 which is larger than an index of refraction n.sub.a1 of a medium adjacent to said beam entrance surface, said beam entrance surface forming angle with said first inside surface defining a first apex angle .varies. such that ##EQU3## 2) a second prism defining a second inside surface and a beam exit surface and being comprised of a material transparent to ultraviolet light within said desired wavelength range and defining an index of refraction n.sub.m2 which is larger than an index of refraction n.sub.a2 of a medium adjacent to said beam exit surface, said beam exit surface, said beam exit surface forming an angle with said second inside surface defining a second apex angle .varies..sub.a2, such that ##EQU4## said first and said second prisms being arranged with said first inside surface facing and parallel to said second inside surface and both prisms being arranged with respect to said laser beam such that said laser beam enters said etalon through said entrance surface at or approximately at Brewster's angle and exits said etalon through said exit surface at or approximately at Brewster's angle.