Fig. 1. Cross section and end face of optical fiber. (a) TBY; (b) ZBYA; (c) PBB; (d) SMF-28e⁺

Fig. 2. Changes in shape of fusion point after fusion of ZBYA and TBY under different main fusion optical powers. (a) 50 bit; (b) 60 bit; (c) 70 bit; (d) 80 bit; (e) 90 bit; (f) 100 bit

Fig. 3. Measurement of welding point loss by truncation method

Fig. 4. Fiber fusion loss versus main fusion optical power after fusion of different types of dissimilar fibers. (a) Soft glass fiber and single-mode quartz fiber; (b) soft glass fiber and soft glass fiber

Fig. 5. Mechanical strength of fusion point versus offset of fire head after fusion of soft glass fiber and single-mode quartz fiber .

Fig. 6. Mechanical strength of fusion point versus offset of fire head after fusion between different soft glass fibers. (a) PBB and TBY; (b) ZBYA and TBY; (c) PBB and ZBYA