Patent ID: 6081320
Filing Date: 2000-06-27
Classification: G03F

Abstract:
An illumination apparatus comprising:a light source emitting a light beam towards an illuminated surface along a reference axis;a beamsplitter located between the light source and the illuminated surface and drawing a portion of the laser beam;a detecting unit detecting the portion of the light beam on a predetermined surface optically conjugate with the illuminated surface;an angle adjusting unit for aligning the light beam along the reference axis;a parallel moving unit for compensating for positional deviations of the light beam; anda light shutting unit having a predetermined aperture;wherein the light shutting unit is located in an optical path between the light source and the predetermined surface while the angle adjusting unit aligns the light beam along the reference axis, and wherein the light shutting unit is located out of the optical path between the light source and the predetermined surface while the parallel moving unit compensates for positional deviation of the light beam.