| 摘要 |
PROBLEM TO BE SOLVED: To improve reliability of output from a photoelectric sensor (illuminance irregularity sensor). SOLUTION: A projection aligner is equipped with a lighting optical system which illuminates a pattern on a reticle 5 as a first object with illuminating light as exposure light, the pattern is transferred on a wafer 9 as a second object or the image of the pattern is formed on a wafer 9 by the use of the above illuminating light, an illuminance irregularity sensor 10 as a measuring means which measures the illuminance of an image plane of the same level with the wafer 9 is provided on a wafer stage 8 which serves as a moving means for the wafer 9, and an ND filter 6 as a dimming means to reduce the amount of illuminating light incident on the illuminance irregularity sensor 10 is arranged on a reticle stage 4. |
