An optimized illumination system that efficiently produces uniform
illumination for exposure, photoablation, and laser crystallization
systems. The illumination system includes a homogenizer that uniformizes
and shapes a light beam, which is directed onto a mask by condenser
optics. The illumination system recycles radiation by directing light
reflected by the mask back into the illumination system, where an
apertured mirror situated at the input end re-directs it back toward the
mask. The relative areas of the mirror and aperture affect recycling
efficiency and system throughput, so the system features a
larger-diameter recycling segment enabling greater mirror-to-aperture
area ratios. An added segment at the output end of the homogenizer
matches the homogenizer diameter to the projection imaging system object
field size. This standardizes the homogenizer and condenser lens
integration, reducing the need for customized parts and thus reducing
manufacturing time and expense.