Development of a System for Measuring Micro Hole Accuracy Using an Optical Fiber Probe

Abstract

This paper presents a system for measuring micro holes that makes use of an optical fiber probe. The optical fiber probe is deflected when it comes into contact with a hole surface, and this deflection is measured optically. For this research, the optical fiber probe is fabricated by using an acid etch technique and its characteristics in the process of displacement detection are described. The effects of surface force are then evaluated. The diameter of the optical fiber probe sphere at the tip of the probe is calibrated by using a 1mm gage block, and the effect of the probe sphere diameter is compensated for measurement of the roughness standard specimen. As a result, it is confirmed that the accuracy after compensation of the roughness standard specimen as measured by the measuring system corresponds well to that of the surface roughness tester in both shape and value, demonstrating the utility of this means of calibration.