| 摘要 |
A lithographic apparatus includes a support configured to hold an object, the support being moveable relative to a reference structure in a direction; a first position measurement system configured to provide a first measurement signal in a first frequency range, the first measurement signal representative of a position of the support relative to the reference structure in the direction; a second position measurement system configured to provide a second measurement signal in a second frequency range, the second measurement signal representative of the position of the support relative to the reference structure in the direction; and a processor configured to (a) filter the first measurement signal so as to attenuate a signal component having a frequency in the second frequency range, (b) filter the second measurement signal so as to attenuate a signal component having a frequency in the first frequency range, and (c) combine the filtered first measurement signal and the filtered second measurement signal into a combined measurement signal representative of the position of the support relative to the reference structure in the direction.
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