| 摘要 |
<p>A supporting device (53) provided with a first part (69), a second part (71), and a gas spring (73) for supporting the second part relative to the first part parallel to a support direction (Z). The gas spring (73) comprises a pressure chamber (75) which is provided in an intermediate part (79) and is bounded by a piston (81) which is displaceable in the intermediate part (79) parallel to the support direction and is supported perpendicularly to the support direction by means of a static gas bearing (85). A stiffness of the supporting device parallel to the support direction is thus substantially entirely determined by a stiffness of the gas spring, and a low stiffness can be achieved through a suitable design of the gas spring. A transmission of vibrations directed parallel to the support direction from the first part to the second part is substantially prevented. In a special embodiment, the intermediate part is displaceable perpendicularly to the support direction over a support surface (105) of the first part (69) by means of a further static gas bearing (103). As a result, the supporting device has a stiffness which is substantially zero perpendicular to the support direction, so that a transmission of vibrations directed perpendicularly to the support direction from the first part to the second part is substantially fully prevented. The supporting device is used in a lithographic device for supporting a frame (39) relative to a base (37), which frame (39) supports a focusing unit (5).</p> |
