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Updated: Jun 14, 2026

Writing Bragg Gratings in Multicore Fibers
Published on: April 20, 2016
Tunable bandpass filter based on force-induced long-period fiber grating in a double cladding fiber
Hajime Sakata1, Keisuke Nishio, Marie Ichikawa
1Department of Electrical and Electronic Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan. thsakat@ipc.shizuoka.ac.jp
Abstract:
We present an all-fiber tunable bandpass filter based on a combination of a force-induced long-period fiber grating and a fiber coil made along a double cladding fiber. The transmission wavelength can be tuned to be in a range of more than 100 nm by changing the grating period mechanically. We can control the transmission amplitude of the bandpass filter by adjusting the periodic force on the double cladding fiber. The ambient temperature causes a positive shift in the transmission wavelength. Such a device is useful for tunable laser applications and fiber-optic sensors.
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