[OPTICAL REVIEW Vol. 4, No. 1A (1997) 104-107]
Optical Irradiation Method for Fiber Coupler Fabrications
Hirohisa YOKOTA, Eiichi SUGAI and Yutaka SASAKI
Department of Systems Engineering, Faculty of Engineering, Ibaraki University, 4-12-1 Nakanarusawa-cho, Hitachi-shi, Ibaraki, 316 Japan
(Received July 1, 1996; Accepted September 9, 1996)
An optical irradiation method for high-speed fiber coupler fabrications without contamination is proposed. In optical fiber taper fabrications we found an interesting effect that fiber elongation is self-arrested although laser irradiation is continued. This is a typical effect in the optical irradiation method, but is not seen in the flame method or the thermal heating method. The gself-controlled fiber taper shape effecth is theoretically explained by considering thermal energy flows, and optical fiber couplers are fabricated using this effect. From our experiments, we show that optical fiber coupler fabrications at high-speed without contamination are possible using the optical irradiation method.
Key words : optical fiber coupler, optical fiber taper, CO2 laser, optical fiber devices, thermal energy flow analysis