Bearing Ball Measurement System with Laser Interferometry Based on Virtual Wavefront Calibration

The laser interferometry measurement system is a non-destructive measurement system with high accuracy. However, when it is utilized to measure the bearing ball, the deviation is introduced unavoidably in the positioning accuracy of the bearing ball to be measured. This deviation conceals the real surface error of the bearing ball, which makes it difficult to guarantee the measurement accuracy of bearing ball. Based on the existing laser interferometry measurement system, a virtual wavefront calibration method is proposed to measure the bearing ball in this paper. With the ray tracing method, the virtual wavefront is generated to compensate the positioning error without any additional component in order to ensure the accuracy of the interferometric measurement system. The experiments show that the maximum positioning error of this measurement system is not more than λ/40 (peak to valley) and λ/80 (root mean square), (λ is the wavelength of measuring light propagation in a vacuum condition), which verifies the effectiveness of this method and this measurement system.