Development of a system to measure micro hole form accuracy using an optical fiber probe (2nd report) - Evaluation of a prototype of the measuring system

This paper presents a micro hole measuring system using an optical fiber probe. The system is composed of a fiber probe, two floodlighting fibers and two double-light reception fibers in the X and Y directions. The fiber probe has an optical fiber of 30μm in diameter with a ball of 50μm in diameter on the end. The probe is deflected when it comes into contact with a hole surface, and this deflection is measured optically. In this research, the accuracy and repeatability of such measurement are examined by measuring a roughness standard specimen and a micro hole. The results clarified that the accuracy of the roughness standard specimen measured by the measuring system corresponds well to that of the surface roughness tester in both shape and value and that the maximum repeatability errors for 10 measurements of a roughness standard specimen is within ±0.03 μn in scanning mode and ±0.1 μm in touch trigger mode.