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.

Development of Touch Probing System Using a Fiber Stylus

“…The measurement sensitivity depends on the diameter of the stylus shaft [28]. Therefore, it is necessary to calibrate the measurement sensitivity when the stylus is replaced.…”

“…To improve the measurement resolution, it is necessary to reduce noise, develop a signal processing method, and use a high-power and stabilized laser diode. As for repeatability and more details on stylus performance, please refer to [28]. …”

“…The diameter of the stylus shaft is smaller than 3 µm, and the stylus shaft has an aspect ratio larger than 200. The stylus shaft is fabricated using an acid etching technique [28]. In general, the stylus shaft must be rigid to transmit the measuring force acting on the stylus tip to the force detection mechanism installed at the root of the stylus shaft.…”

“…The probing system consists of the fiber stylus, two laser diodes (LDX, LDY), and two dual-element photodiodes (PX, PY) facing the X and Y directions. The stylus shaft is fabricated using an acid etching technique [28]. First, the step index multi-mode optical fibers (core diameter: 100 µm, clad diameter: 125 µm) were stripped of their plastic layers.…”

Traceable profile and roughness measurements inside micro sonic nozzles with the Profilscanner

“…However, the precision of this system is limited to about 0.5 µm. The fibre probe based technology [4][5][6][7][8][9][10][11] is another approach for the measurement of HARMS and some of these measurement systems have already been utilized commercially. In this technology a slim fibre with a micro ball at the end is employed for probing, and the surface positions are inferred through detecting the positions of the ball probe by various sensing methods, e.g., imaging the shadow of the probing systems using a camera.…”