A novel optical coupling scheme that uses a lensed fiber integrated with a long-period fiber grating (LPFG) is proposed. Two experiments are performed to demonstrate the validity of such a scheme in single-mode-fiber–single-mode-fiber (SMF-to-SMF) and laser-diode–single-mode-fiber (LD-to-SMF) coupling setups. The measured results show that for an appropriate lens radius the addition of a LPFG will lead to a higher coupling efficiency over a longer range of working distance than without the LPFG. Coupling efficiencies of ∼78% and 35% are achieved for corresponding working distances of ∼250 and 110 µm, 1-dB longitudinal tolerances of ∼40 and 26 µm, and 1-dB transverse tolerances of ∼7.6 and 2.6 µm for SMF-to-SMF and LD-to-SMF, respectively.
© 2000 Optical Society of America
Original Manuscript: January 14, 2000
Published: September 1, 2000
Wen Tzung Chen and Lon A. Wang, "Optical coupling method utilizing a lensed fiber integrated with a long-period fiber grating," Appl. Opt. 39, 4490-4500 (2000)