We propose a novel transmission scheme to extend the single-mode operation range of a conventional single-mode fiber (C-SMF) to wavelengths shorter than the cutoff wavelength. It involves the use of a tapered-fiber mode filter (MF) in order to remove the high-order-mode power from the C-SMF and hence, makes the fiber work as a virtually single-mode transmission link. High-order mode suppression of above 10 dB has been achieved at wavelengths of 850 and 980 nm with a fabricated tapered-fiber MF. We have also demonstrated the feasibility of the technique by evaluating the transmission quality with the MF at 850 nm through a 5-km C-SMF having a cutoff wavelength of 1.2 μm.
Bibliographical noteFunding Information:
Manuscript received May 17, 2005; revised August 9, 2005. This work was supported in part by KOSEF through UFON, an ERC program of GIST, in part by KISTEP through Critical Technology 21 programs, and in part by the BK-21 IT Project, MOE, Korea.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering