Fitzpatrick, Cella Harper & Scinto
Stage apparatus for an exposure apparatus including a contant tension spring for canceling out a gravitational force of a movable stage by a tensile force
 An X-stage is moved in an X direction (horizontal direction), and a Y-stage is moved in a Y direction (vertical direction) by linear motors. The gravitational force of the Y-stage is canceled out by a constant tension spring. Tensile force irregularity in the constant tension spring is measured in advance and stored in a tensile force irregularity compensation table. The tensile force irregularity is canceled out when a controller controls an auxiliary motor. 
Canon Kabushiki Kaisha
G G
G03F G03F
inventional inventional
Nobusige Masamichi
Korenaga Saito