We have evaluated the performance of strain-chirped fiber Bragg grating (FBG) based tunable dispersion compensator in a 40 Gb/s transmission link. In our proposed compensator, the value of dispersion could be changed from -353 ps/nm to -962 ps/nm by adjusting the rotation angle of the metal beam on which the FBG was mounted. In order to evaluate the effect of ripples in reflectivity and variati...

We solve the coupled mode equations governing the chalcogenide nonlinear fiber Bragg gratings (FBGs) numerically, and obtain the bistability characteristics. The characteristics of the chalcogenide nonlinear FBGs such as: switching threshold intensity, bistability interval and on-off switching ratio are studied. The effects of FBG length and its third order nonlinear refractive index on FBG cha...

We propose and experimentally demonstrate a 2.5 Gbits/sper user wavelength-encoded optical code-division multiple-access encoder-decoder structure based on opto-VLSI processing. Each encoder and decoder is constructed using a single 1D opto-very-large-scale-integrated (VLSI) processor in conjunction with a fiber Bragg grating (FBG) array of different Bragg wavelengths. The FBG array spectrally ...

A Fiber Bragg grating of 369 nm pitch was inscribed in a germanium-free double-clad ytterbium doped silica fiber using a femto-second pulse train at 400 nm wavelength and a phase mask. The photo-induced refractive index modulation of higher than 4 x 10(-3) was obtained and the accompanying photo-induced losses were subsequently removed by thermal annealing, resulting in a low loss (<0.1 dB), st...

An orientation-dependent displacement sensor based on grating inscription over a fiber core and inner cladding has been demonstrated. The device comprises a short piece of multi-cladding fiber sandwiched between two standard single-mode fibers (SMFs). The grating structure is fabricated by a femtosecond laser side-illumination technique. Two well-defined resonances are achieved by the downstrea...

We present the design, fabrication and testing of the piece-wise stepped-chirp fiber Bragg gratings (FBGs) with arbitrary group delay responses using a uniform phase mask under pre-stretched condition. The method involves writing a series of sub-gratings on a prestretched fiber whose length is varied during the UV exposure process. Two motorized stages are employed to control the length of the ...

We will demonstrate a new technique to discriminate the temperature and strain effects using a single fiber Bragg grating (FBG). The birefringence is typically induced during FBG inscription, and it is manifested as polarization-dependent loss (PDL), and it is defined as the maximum change in the transmitted power for polarizations. Two independent measurements of the resonance wavelength shift...

In this review paper some recent advances on optical fiber sensors are reported. In particular, fiber Bragg grating (FBG), long period gratings (LPGs), evanescent field and hollow core optical fiber sensors are mentioned. Examples of recent optical fiber sensors for the measurement of strain, temperature, displacement, air flow, pressure, liquid-level, magnetic field, and the determination of m...

The field of structural health monitoring is concerned with accurately and reliably assessing the integrity of a given structure to reduce ownership costs, increase operational lifetime, and improve safety. In structural health monitoring systems, fiber Bragg grating (FBG) is a promising measurement technology for its superior ability of explosion proof, immunity to electromagnetic interference...

A brief historical narrative of the study of grating solitons in fiber Bragg grating is presented from the late 1970’s up to now. The formation of photogeneration gratings in optical fiber by sustained exposure of the core to the interference pattern produced by oppositely propagating modes of argon-ion laser radiation was first reported in 1978. One important nonlinear application of fiber Bra...