| 摘要 |
A lithographic apparatus having a stationary magnet motor to drive a support such as a substrate support or a patterning device support, may be provided with a measurement system to measure a position of the support in question, e.g., to provide a safety system to prevent a collision of the support with another part. The measurement system may be configured to measure a magnetic field strength of an alternating magnetic field generated by the magnet assembly of the stationary magnet motor, and/or measure generation of eddy currents in a metallic layer shielding the magnet assembly in combination with an inductance measurement of an electromagnet generating the alternating magnetic field causing the eddy currents, and/or measure light using an optical position sensitive sensor such as a CCD metric or linear photodiode positioned in a light plane emitted by an emitter. |
