抄録
Optical measuring method for run-out of spindle with ball mirror and auto-oollimator is studied. However, the measuring result is estimated to include error by unevenness of reflectance on surface of ball mirror. Three-point method is one of measuring methods not to be affected by error of datum. Therefore, three-point method is introduced to remove the errors due to unevenness of reflectance. It is shown that three-point method is successfully applied to the optical measuring device for spindle rotation accuracy through ray tracing simulation.
