High Precision Laser Deep-hole Diameter Measurement Based on DynamicAbbe′s Principle

The ultra-precision measuring of deep-hole diameters is a tough task of inner size measurement.A method of laser deep-hole diameter measuring were presented based on dynamic Abbe′s principle.The measurement system integrates the length measurement technique of dual frequency laser interfere and the aiming method of dual-direction capacitance displacement sensor.Through the suitable arrangement of capacitance displacement aiming sensor,length and depth measuring optical paths,it was ensured the any section hole-diameter′s measurement of deep hole follows the Abbe′s principle.Six standdard gauges between Φ 5 mm and Φ 16 mm were employed to test the characteristic of the system.The ultra-precision measurements of the deep-hole′s any section hole diameters were experimentally realized by this system.The resolution is 10 nm and the uncertainty is 0.1 μm.