AUTOMATIC CORRECTION MECHANISM FOR SIX DISPLACEMENT COMPONENTS OF LINEAR MOVING BODY USING STRAIGHT-ADVANCING LASER BEAM AS REFERENCE SOURCE

摘要

PROBLEM TO BE SOLVED: To automatically correct all six displacement components of a linearly moving body by using a unit consisting of a photodetector which detects the displacement of light to a correction reference laser beam and a servo circuit of a displacement correction device. ;SOLUTION: The sensors Sθ₁ and Sθ₂ are provided on a flat plate 7 along the passing position of a correction reference laser beam α together with the sensors Sz₁ and Sz₂ placed along the passing position of a correction reference laser beam β respectively. A moving stage 2 contains the vertical component displacement correction devices Az₁ to Az₂ in a plane rectangular to the pitching, rolling and moving directions of the stage, the horizontal component displacement correction devices Aθ₁ and Aθ₂ in a plane rectangular to the yawing and moving directions of the stage and a displacement correction device Ax₁ prepared against the moving direction of the stage respectively. Then, a sensor Sx₁ is connected to the device Ax₁ via a servo circuit. In such a constitution, all six displacement components of a linearly moving body can be easily and automatically corrected even for a large-size ultraprecise positioning device.;COPYRIGHT: (C)1998,JPO