| 摘要 |
A stage apparatus comprising a support device for supporting a table at its center of gravity and a drive device for driving the table at positions apart from the center of gravity of the table without contacting with the table. The stage apparatus effectively reduces stresses created in the table and/or any thermal deformation of the table. The table is connected to three pairs of table support bars on the stage through three respective plate springs so as to minimize any harmful deformation of the table, which could otherwise occur when the table is driven for motion or displacement in the Z-direction or for adjustment of the tilt of the table. The stage apparatus includes three drive units with respective drive pins for driving the stage. For example, when the three drive pins are driven simultaneously by the associated drive units, the table is caused thereby to translate along the Z-axis. The drive pins are so arranged as to provide support for the table at support points just under respective securing points on the table at which the table is secured to the plate springs and to provide a drive for the, table in the Z-direction at the support points. Thus, when driven by the drive pins, the table is only subject to compression forces acting thereon in the Z-direction and not to any moment.
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