US Patent 6839975 Accuracy measuring apparatus for machine tool

The present invention relates to an accuracy measuring apparatus which is capable of efficiently measuring the accuracies of a machine tool at low costs. The accuracy measuring apparatus (1) comprises a laser oscillator (2) attached to a spindle (15) of the machine tool (10) for projecting a light beam having an axis aligning with the axis of the spindle, a CCD camera (3) disposed in opposed relation to the laser oscillator (2) for receiving the light beam projected from the laser oscillator (2) and generating two-dimensional image data, and an analyzer (4) for analyzing the image data to determine the accuracies of the machine tool (10).