| 摘要 |
<p>A lithographic projection apparatus comprising: a radiation system (Ex,IN,CO) for supplying a projection beam (PB) of radiation; a support structure (MT) for supporting patterning means (MA), the patterning means serving to pattern the projection beam according to a desired pattern; a substratre table (WT) for holding a substrate (W); and a projection system (PL) for projecting the patterned beam onto a target portion (C) of the substrate; characterized by: a measurement system for measuring wave front aberrations of the projection system (PL), the measurement system comprising a grating (7) that is movable into the projection beam between the radiation system (Ex,IN,CO) and the projection system (PL), and a pinhole arranged in a pinhole plate (11) that is movable into the projection beam between the projection system (PL) and a detector (13) for detecting light traversing the pinhole. <IMAGE></p> |
