Patent ID: 11940264
Assignee: ASML NETHERLANDS B.V.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 14:
15. A lithographic apparatus comprising:
an object to be positioned;
an actuator system to position the object;
a measurement system including an interferometer system, which interferometer system includes a first interferometer and a second interferometer, wherein the first interferometer is arranged to provide a first position signal representative of a position of the object in X-direction by directing a first measurement beam on a first mirror, wherein the second interferometer is arranged to provide a second position signal representative of the position of the object in X-direction by directing a second measurement beam on a second mirror, wherein the first mirror and the second mirror are arranged on opposite sides of the object and mainly extend in a Y-direction; and
a control system to drive the actuator system based on an output of the measurement system,
wherein the control system is configured to carry out the method according to claim 1.