Patent ID: 7307708
Filing Date: 2007-12-11
Classification: G01M

Abstract:
1. An eccentricity measuring method, comprising: a first moving step of moving a surface to be tested relative to an optical system along a measurement reference axis; projecting an index to an apparent spherical center position of at least the surface to be tested through the optical system; a second moving step of moving the surface to be tested relative to the optical system in a direction perpendicular to the measurement reference axis based on a position of a reflection image which is obtained by reflecting an image of the index by the surface to be tested; using a sensor to detect a value of a relative movement quantity between the surface to be tested and the optical system in the direction perpendicular to the measurement reference axis; and calculating an eccentric quantity of the surface to be tested as a function of the value of the relative movement quantity between the surface to be tested and the optical system in the direction perpendicular to the measurement reference axis.