| 摘要 |
PURPOSE:To aim at adjusting a table device with a high degree of accuracy and at miniaturizing the same, by individually driving two drive devices in accordance with the height and inclination of a workpiece or the like set on the table device, and by manipulating three adjusting cams so that the table device is inclined by means of cam followers to adjust the height thereof. CONSTITUTION:If there is any blur in the image of a semiconductor wafer 58 set on a work table 54, an Z-axis motor 15 rotates a feed screw 17 to move a table 12 back and forth, integrally therewith, and adjusting cams 23, 43, 44 are moved in the same direction and by the same distance. Even after the table 54 being vertically and parallely moved to adjust cam followers 47-49 which make into rolling contact with the cam surfaces 24, 45, 46, if any other part in the image is not yet in focus, the inclination is further adjusted. That is, in order to focus a pattern above the cam 43, a motor 29 for driving a table 25 is alone energized to move the table 25 back and forth, independently. Fur ther, in order to focus a pattern above the final cam 44, a motor 30 is alone energized to move a table 25 back an d forth, independently. Thereby it is possible to facilitate the highly accurate adjustment of the table device. |
