| 摘要 |
A stage apparatus of the present invention includes a plurality of interferometers 14H, 14J, 14R for measuring the displacements of a fine adjustment stage 11 at respective measuring sites, a plurality of actuators 29h, 29j, 29r for independently moving the stage 11, and a mathematical operational conversion unit 43. Deviations DELTA H, DELTA J and DELTA R are derived by a subtracting displacements H, J, R of the stage 11 actually measured by the interferometers from the target displacements HT, JT, RT of the stage 11, and supplied to the mathematical operational conversion unit 43, where the target driven increments DELTA h, DELTA j, DELTA r are derived by a calculation using a predetermined mathematical model (this model is an inverse matrix T-1, which is the inverse of the matrix T describing the operation for deriving the displacements measured by the interferometers from the displacement produced by the actuators). The rotational speed controllers 39A, 39B, 39C of the actuators are driven by the amounts h, j, r that correspond to the target driven increments DELTA h, DELTA j, DELTA r. This results in a reduced effect of any mechanical interference, so that the positioning of the fine adjustment stage 11 can be quickly achieved with high accuracy.
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