Abstract
This paper proposes a non-contact and on-machine measurement method for evaluating tool edge geometry. A focused laser beam having a diameter of several micrometres traces over the tool edge, while the both of signals are monitored. By utilizing a light intensity of the laser beam passed around the tool, the perpendicular distance between the optical axis and the tool edge is obtained. Measurements have been carried out with a scanning speed of 16.7 μm/s on the ultra-precision machine lathe. The measurement resolution of 30 nm of the method can be developed to greater than the diffraction limit.
