Characterization of excimer lasers for application to lenslet array

Summary form only given. Lenslet homogenizers are often used to improve the uniformity of illumination in condenser systems for photolithography. A typical photolithographic optical system is illustrated schematically. A lenslet array, simplified to a 3/spl times/3 element array for the drawing, forms an array of point sources. The condenser lens reimages the array of point sources into the pupil of the relay lens. The relay lens images the plane of the mask (target plane) onto the photographic medium.