| 摘要 |
PURPOSE:To enable the inspection of contamination by dust or the like of an original plate immediately before exposed to light, by sweeping the original plate with the irradiation with a light beam from the side of a sample surface through an projection system to detect the light beam passing through the original plate. CONSTITUTION:A laser light emitted from a laser sweeps a reticle 7 through a projection lens 6 through a rotary mirror 2, an F-theta lens 3 and a reflection mirror 5. At this point, the reflection mirror 5 moves in the direction of the arrow through a moving stage 4 to scan a pattern surface of the reticle 7 with the laser light. On the other hand, a detector 13 fixed on a lighting system 13 detects the light beam transmitted through the reticle 7 through an image formation optical system 11. The pattern information thereof is sent to a signal processing meter 14 to be compared with reticle pattern information 15 obtained in a dustless condition, thereby detecting the attached position of dust or the like. |
