Fabrication optimization of a micro-spherical fiber probe with the Taguchi method

This paper describes a low-cost and efficient method to fabricate a micro-spherical fiber probe using a commercial fiber fusion splicer based on the Taguchi method. Based on the principles of electric arc discharging energy absorption and the surface tension phenomenon, a microsphere can be formed at the end of the optical glass fiber. The optimum parameters to control the geometrical accuracy of the probe were selected according to the Taguchi method with the signal-to-noise ratio and the analysis of variance processes. From the results, a spherical probe about 310 µm in diameter with less than 1 µm in roundness error could be produced using a 125 µm diameter single-mode optical fiber. The offset distance between the ball center and the fiber stylus central line due to the gravity effect could also be controlled to less than 1 µm after optimization of the parameters. The microprobe can be used for the contact-type stylus head to enhance the resolution and extend the capability of measuring meso- to micro-objects