Chebyshev Freeform Microlens Array Homogenizer for Excimer Laser Beam Shaping

A novel design technique of microlens optical beam homogenizing system for excimer lasers is presented. As a new approach by applying Chebyshev freeform surface microlens array, the homogenizer can yield somehow superior beam shaping results with larger but less microlens units than conventional method, while the diffraction effects at the microlens apertures can be reduced substantially. With this new concept and design, large scale and highly uniform beam profile can be generated at a relative nearby working distance after beam shaping, which is hard to achieve by conventional methods.