DIAL INDICATORS CHECKING-UP BY LASER INTERFEROMETRY

Dial indicators are mechanical gauging devices widely used for measure ments in high accuracy machining. Checking-up the measuring accuracy o f these devices, by classical means, is a time-consuming task for both manufacturers and users of dial indicators. Laser-based equipment for a fast and accurate checking-up of all types of dial indicators, acco rding to international standards, is reported. This article contains t he description of the equipment's operating principle, the constructio n of the specially designed angular transducer used for the dial indic ator's hand angular movement reading, and the Michelson interferometer . The length measuring accuracy is 0.15 mu m, while the dial indicator 's hand angular detection accuracy is 0.25 degrees. (C) 1996 American Institute of Physics.