We describe the use of a matched linearly chirped fiber Bragg grating (FBG) pair as a key element in an adjustable optical delay line. This delay line has the unique property that the achievable optical group delay is orders of magnitude greater (factor of 10<sup>2</sup> in our experiment) than the actual physical displacement. We demonstrate operation of such an optical delay line over a delay range of 3.5 mm using a pair of matched 1300-nm chirped FBGs with a bandwidth of 20 nm each.
© 2004 Optical Society of America
(050.2770) Diffraction and gratings : Gratings
(110.4500) Imaging systems : Optical coherence tomography
(120.3180) Instrumentation, measurement, and metrology : Interferometry
(230.1480) Optical devices : Bragg reflectors
Changhuei Yang, Siavash Yazdanfar, and Joseph Izatt, "Amplification of optical delay by use of matched linearly chirped fiber Bragg gratings," Opt. Lett. 29, 685-687 (2004)