| 摘要 |
<P>PROBLEM TO BE SOLVED: To measure a position of a stage with a high precision by suppressing an air fluctuation on an optical path of a laser interferometer for measuring the position of the stage. <P>SOLUTION: Exhausting means is provided at a stator of a flat surface motor for driving the stage, and a heated air blown off from blast means is efficiently retrieved. The fluctuation on the optical path is lessened by preventing the blown heated air from colliding against the front surface of the stator and from curling up in the sky, and by preventing an air heated by heat generation of the stator from rising on the optical path. <P>COPYRIGHT: (C)2007,JPO&INPIT |
