Continuum generation from normally dispersive ultrahigh-numerical-aperture fibers deteriorates in relatively short times, limiting its application as a practical optical source for high-resolution optical coherence tomography. We find that reversible light-induced structural modification of fiber optic materials, rather than permanent optical damage, is responsible for this deterioration. By ex...

A highly porous optical-fiber cladding was developed for evanescent-wave fiber sensors, which contains sensor molecules, maintains guiding conditions in the optical fiber, and is suitable for sensing in aqueous environments. To make the cladding material (a poly(ethylene) glycol diacrylate (PEGDA) polymer) highly porous, a microsphere templating strategy was employed. The resulting pore network...

Two different fiber optic sensors were developed for the determination of hydrogen sulfide at ppb concentration levels; a probe-type fiber optic sensor coated with polyethylene oxide containing 0.5 M CdCl(2) and a fiber optic sensor utilizing 0.5 M CdCl(2)-pretreated filter paper as solid substrate. In the first type, CdCl(2)-polyethyleneoxide (PEO) mixture was coated onto the tip of a fiber op...

Surface plasmon resonance based tapered fiber optic refractive index sensor incorporating an additional high index dielectric layer between metal and sensing medium using wavelength interrogation method is analyzed. The simulation is carried out for gold and silver metals. The simulation predicts, for a given taper ratio, the increase in the sensitivity of the sensor with increase in the thickn...

Two optical techniques are experimentally investigated to measure the shock wave velocity and particle velocity in metals subjected to hyper velocity impacts. Fabry-Perot interferometer based optical system has been developed and used to measure the interface velocity profile of impacted Tantalum-Glass and Aluminum-Glass targets. Optical fibers coupled to fast photodiodes are implemented to mea...

Bonneville Power Administration is investigating wide-area stability and voltage control. The control provides a flexible platform for rapid implementation of generator tripping and reactive power compensation for voltage support and stability. Features include phasor measurements, digital fiber optic communications, and fuzzy logic control. The control includes both fast and slow subsystems. T...

Dense Wavelength Division Multiplexing (DWDM) enables the utilization of a significant portion of the available fiber bandwidth by allowing many independent signals to be transmitted simultaneously on one fiber, with each signal located at a different wavelength. In this paper, the two major non-linear effects such as FWM and SRS in transmission fiber must be simultaneously eliminated by Duobin...

The extremely low loss of silica fibers has enabled the telecommunication revolution, but single-mode fiber-optic communication systems have been driven to their capacity limits. As a means to overcome this capacity crunch, space-division multiplexing (SDM) using few-mode fibers (FMF) has been proposed and demonstrated. In single-mode optical fibers, Rayleigh scattering serves as the dominant m...

For actively modulated In-line Sagnac interferential all optic fiber current transformers (AOFCTs), the accuracies are directly affected by the amplitude of the modulation signal. In order to deeply undertand the function of the modulator, a theoretical model of modulation effect to AOFCTs is built up in this paper. The effect of the amplitude of the modulation signal to the output intensity of...

This paper provides an overview of considerations associated with placement and operation of fiber optic sensors placed in composite materials. Issues that are discussed include coatings placed on optical fibers and their relationship to the composite structure, orientation of optical fibers in the composite parts, methods of providing strain relief, and terminations. Examples are given associa...