LIGHT BEAM INTENSITY NON-UNIFORMITY CORRECTION DEVICE AND METHOD FOR AMENDING INTENSITY DISTRIBUTION OF A LIGHT BEAM

摘要

The invention relates to a light beam intensity non-uniformity correction device (34) comprising an optical element (34) having a light entrance face (36) with an antireflective property. According to the invention said antireflective property is locally amended in order to enhance light beam intensity uniformity. The invention further relates to a method for amending intensity distribution of a light beam (12) in an optical system (2) having one optical element or a plurality of optical elements (16, 24, 26, 34), comprising the steps of: a) assembling said optical system (2) with said optical elements (16, 24, 26, 34) being arranged in predetermined positions, b) measuring intensity distribution, c) calculating locally required increase or decrease in absorption and/or reflection of one of said optical elements (34) in order to amend measured intensity distribution into a predetermined intensity distribution, d) removing said one of said optical elements (34) from said optical system (2), e) locally amending absorption and/or reflection of said one of said optical elements according to the calculation, f) installing said one of said optical elements (34) in said predetermined position in said optical system (2).