Vibration isolation device, lithographic apparatus and method to tune a vibration isolation device

摘要

The invention provides a vibration isolation device configured to support a structure, comprising:;an air mount having a base part mounted on a reference structure and a vibration isolated part, and;an inverted pendulum device, wherein a lower end of the inverted pendulum device is mounted on the vibration isolated part of the air mount and an upper end of the inverted pendulum device support the structure to be supported,;wherein the vibration isolation device comprises a stiffness adjustment device configured to adjust the stiffness of the inverted pendulum device.