Patent ID: 7869970

Claim:
A probe straightness measuring method for measuring a straightness of a probe, comprising: providing a surface texture measuring machine, the surface texture measuring machine comprising: a table having a stage surface for an object to be measured to be placed, the table being movable in a direction parallel to the stage surface; and a probe comprising a casing, a measurement piece provided to the casing in a movable manner to be brought into contact with a surface of the object to be measured, a measurement-piece moving mechanism that displaces the measurement piece in a direction substantially orthogonal to the stage surface of the table and a displacement detector that detects a displacement of the measurement piece relative to the casing, a surface texture of the object to be measured being measured while relatively moving the table and the probe to bring the measurement piece of the probe into contact with the surface of the object to be measured, the straightness of the probe being measured when the probe is displaced in the direction substantially orthogonal to the stage surface of the table by the measurement-piece moving mechanism; placing a measurement jig having a measurement reference surface with a known profile error and with a slant angle relative to the stage surface on the stage surface of the table so that the measurement reference surface is slanted in a moving direction of the table; measuring a displaced position of the measurement piece by the displacement detector after moving the table for a predetermined distance while controlling the measurement-piece moving mechanism so that the measurement piece of the probe touches the measurement reference surface of the measurement jig at a constant pressure; and calculating a straightness error of the probe on a basis of a measured position of the measurement piece obtained by the measuring, a nominal position of the measurement piece supposing that the measurement piece is ideally displaced without the straightness error and the slant angle of the measurement reference surface.