METHOD AND DEVICE FOR CORRECTING ZERO-POINT ERROR IN SEQUENTIAL THREE-POINT METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method and device for correcting a zero-point error in a sequential three-point method capable of simultaneously detecting shape information and motion errors on the occasion of measurement, with a plurality of displacement sensors without using an entity reference, and separating and deriving them by arithmetic operation.;SOLUTION: By a sequential three-point method, an object to be measured 100 and displacement sensors 31-33 are relatively moved, and based on the detection outputs of the displacement sensors 31-33, the surface profile of the object 100 by the sequential three-point method is operated arithmetically. Before and after an object to be measured 200 is inverted respectively, the objects 100, 200 and displacement sensors 41, 42, 32 are moved relatively, and based on the detection outputs of the displacement sensors, the surface profile of the object 100 by an inversion method is operated arithmetically. Based on the results of the arithmetic operations for the surface profile of the object 100 by the sequential three-point method and the inversion method, the amount of zero-point error correction is calculated, and zero-point error correction by the sequential three-point method is performed by the amount of the zero-point error correction.;COPYRIGHT: (C)2007,JPO&INPIT