On-machine metrology for diamond turning applications

A dual-mode on-machine metrology system has been developed to address the critical demand for on-machine metrology in precision optics fabrication. The system can measure both surface form and roughness simultaneously, without requiring the reconfiguration of the optical path to switch between laser interferometer mode and LED interference microscopy mode. It can achieve snapshot high-precision phase-shifting measurement, minimizing the impact of environmental disturbance. With its compact design, the system makes on-machine metrology feasible in diamond turning machines, avoiding errors caused by removing, repositioning, and balancing the workpiece. With the compact and dual-mode features, it makes on-machine tool alignment and surface characterization possible, avoiding off-line testing and significantly increasing process efficiency.