CORRECTION VALUE DERIVATION APPARATUS, DISPLACEMENT AMOUNT DERIVATION APPARATUS, CONTROL APPARATUS, AND CORRECTION VALUE DERIVATION METHOD

摘要

This invention improves detection precision by reducing a detection error of a change in position of a target. A correction value derivation apparatus for deriving a correction value used in correction of a displacement amount derived based on an encoder signal indicating a change in position of a movable portion as a target, comprises: a displacement amount derivation unit configured to derive a detected displacement amount of the movable portion based on the encoder signal; a displacement velocity derivation unit configured to derive a detected displacement velocity based on the detected displacement amount derived by the displacement amount derivation unit; an average displacement velocity calculation unit configured to calculate an average displacement velocity over a predetermined displacement range; and a correction value derivation unit configured to derive the correction value based on the detected displacement velocity and the average displacement velocity.