| 摘要 |
<P>PROBLEM TO BE SOLVED: To use a measuring optical system or the like suitably in a measuring device arranged in a vacuum chamber. <P>SOLUTION: The measuring device arranged in a vacuum chamber comprises: a measuring optical system which is arranged in the vacuum chamber and measures the position or height of a substrate; a cover which seals and covers at least a part of the measuring optical system; piping for supplying gas into the cover and discharging it; and pressure control means to control the pressure in the cover by controlling the quantity of the gas to be supplied into or discharged from the cover suppresses the pressure in the cover, and controls the quantity of the gas so that a predetermined pressure difference can be generated in/out of the cover. The measuring optical system corrects aberrations generated by deformation of the transparent plate due to pressure difference. <P>COPYRIGHT: (C)2012,JPO&INPIT |
