ANALYTICAL BEAM SHAPING WITH APPLICATION TO LASER-DIODE ARRAYS

In contrast to numerical methods for beam shaping, analytical beam sha ping consists of two steps: first, finding a purely geometrical distor tion between the input plane and the output plane redistributing the i ntensity of the incoming wave front; and, second, computing a phase-on ly element realizing this coordinate transform. For the latter the met hod of stationary phase may be applied. The known classes of possible analytical wave transformation are extended to comprise separable and isotropic super-Gaussian-to-super-Gaussian conversion as well as trans formation of Gaussian arrays to super-Gaussian distributions, and vice versa. The resulting optical phase elements contain no spiral phase d islocation and may thus be realized as refractive or diffractive eleme nts. In addition, the outgoing wave front does not contain spiral phas e dislocations. (C) 1997 Optical Society of America.