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.
© 2010 Optical Society of America
Original Manuscript: December 22, 2009
Manuscript Accepted: January 18, 2010
Published: March 31, 2010
Hajime Sakata, Keisuke Nishio, and Marie Ichikawa, "Tunable bandpass filter based on force-induced long-period fiber grating in a double cladding fiber," Opt. Lett. 35, 1061-1063 (2010)