| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce the effect of gas fluctuation and improve measurement accuracy, by eliminating both of positioning error of measurement with an interferometer and an error due to principles of Abbe by position detection sensor using diffraction grating. <P>SOLUTION: The device has stages 1 and 2 having a direct action guiding mechanism, laser interferometers 3a and 3b and two positioning measurement means in the axial direction of position detection sensors 8a, 9a; 8b, 9b, which are less likely to be affected by the variations in the refractivity of gas, as compared with the laser interferometer. For the shift of the target of stage positioning which is indicated by signals of two position measurement means, the position shift indicated by the opto-electric signal of the laser interferometers 3a and 3b is used for positioning control of the low-frequency region, and the position shift indicated by signals of the position detection sensors 8a, 9a; 8b, 9b is used for positioning control of the high-frequency region. <P>COPYRIGHT: (C)2004,JPO |
