Excimer laser beam shaping using diffractive optics

Summary form only given. The output energy distribution of an excimer laser is typically asymmetric characterized by a nearly Gaussian distribution along the short axis and a flat-top distribution with Gaussian wings along the long axis. Many applications of UV lasers, however, call for a more homogeneous energy distribution with steep and well-defined edges. Diffractive optics provides powerful means for beam shaping. Simple, low-loss optical systems are possible, since multiple functions can be performed with a single element. Periodic elements, especially, are attractive, because they are not sensitive to lateral beam alignment or to variations in the incident beam shape. Here we demonstrate a periodic diffractive flat-top generator for an excimer laser. We make use of the partial coherence of the multi-spatial-mode laser source to smooth the output signal.