| 摘要 |
The invention relates to a lithographic apparatus arranged to transfer a pattern from a patterning device onto a substrate, wherein apparatus is operable to measure higher-order distortions and/or image plane deviations of the patterning device, apparatus comprising: a device for transmission image detection; and a processor configured and arranged to model higher-order distortions of the patterning device using signals received from the device for transmission image detection; wherein patterning device has a main imaging field, and a perimeter and apparatus is operable to model higher-order distortions using signals resultant from alignment structures comprised in perimeter and/or in the imaging field. |
