Measurement of a tool wear profile using confocal fluorescence microscopy of the cutting fluid layer

When using conventional optical methods in the on-machine environment, it is difficult to precisely evaluate tool geometry because the cutting fluid covering the tool surface reduces measurement accuracy owing to noisy light scattering. To overcome this problem, the principle of measurement based on the confocal detection of fluorescence emitted from the cutting fluid is proposed. The proposed method was fundamentally validated by measurement results for detailed tool wear profiles. This novel measurement technique produces results with sub-micron accuracy.