Reduction in the angular divergence of laser radiation with an exit reflector composed of several mirrors characterized by an inhomogeneously distributed transmission

Experiments demonstrated that angular divergence of neodymium glass laser radiation could be reduced without a significant loss of the energy per pulse if use was made of a composite exit reflector in the form of two or three apodized mirrors consisting of zinc sulfide films of nonuniform thickness on glass plates with antireflection coatings.