Design of extreme anamorphic laser illumination systems

Many laser applications, for example material processing or fluorescence imaging, require intense and uniform illumination over a rectangular, slit shaped area with extreme aspect ratio: The short dimension of the illumination field typically requires diffraction limited imaging, respectively focusing, on a micrometer scale. In contrast the extension in the long dimension can be hundreds of millimeters. This class of systems requires a highly anamorphic system design for the homogenization as well as for the projection of the illumination pattern. Aberrations within the projection optical system, as for example induced by cylindrical optical components, need to be analyzed and controlled. In some cases the application additionally requires the substrate to be illuminated under some tilted angle, which requires specific solutions within the optical design. We will illustrate corresponding design examples and solutions for this class of illumination systems.