Now showing items 1-10 of 18
Stress-dependent growth kinetics of ultraviolet-induced refractive index change and defect centers in highly Ge-doped SiO2 core fibers
(AIP Publishing, 1999-10-01)
The evolution of the index change of type-IIa gratings observed in 28 mol % Ge-SiO2 core fibers with 1.8 mu m core diameter under various strains was measured from the optical spectra, and the induced defects at high and ...
Uniform component of index structure induced in Ge-SiO2 fibers by spatially modulated ultraviolet light
(AIP Publishing, 1998-06-01)
Experimental data are presented to show that Ge(1) and Ge(2) centers are induced by trapping photoinduced electrons from the conduction band, in agreement with our previous proposal that both are trapped electron centers. ...
Microbend loss fiber optic direction and amplitude sensors for underwater applications
(Acoustical Society of America, 1990-07-01)
Dual purpose fiber optic microbend loss sensors have been developed for measurement of underwater acousticwave amplitudes and for detection of the direction of wave propagation. Three different construction schemes for ...
Structural origin of the 5.16-EV optical-absorption band in silica and GE-doped silica
(AIP Publishing, 1994-03-01)
The origin of the 5.16 eV absorption band observed in silica and Ge-doped silica was studied using optical and electron spin resonance (ESR) measurements. The band was observed only in samples containing Ge, suggesting ...
Dynamics of the 5-EV optical-absorption in SIO2 glass
(AIP Publishing, 1993-06-01)
The optical absorption at 5 eV in SiO2 glass was observed, using laser calorimetry, to change reversibly depending on the intensity of UV light. The generation and bleaching of an absorption band at 5 eV by two- and ...
Sapphire Fibers: Optical Attenuation And Splicing Techniques
(Optical Society of America, 1995-12-01)
The optical attenuation in sapphire fibers was examined. Attenuation was found to depend heavily on injection conditions. A number of techniques for making sapphire-silica fiber splices were attempted, with an effort toward ...
Miniaturized Fiber-Optic Michelson-Type Interferometric Sensors
(Optical Society of America, 1991-03-01)
We present a novel, miniaturized Michelson-type fiber-optic interferometric sensor that is relatively insensitive to temperature drifts. A fused-biconical tapered coupler is cleaved immediately after the coupled length and ...
Characterization And Modeling Of Drift Noise in Fourier Transform Spectroscopy: Implications For Signal Processing And Detection Limits
(Optical Society of America, 1997-05-01)
A theoretical analysis of long-term drift noise in Fourier transform spectroscopy is presented. Theoretical predictions are confirmed by experiment. Fractional Brownian motion is employed as a stochastic process model for ...
Separation of Intrinsic and extrinsic Optical-Absorption in a Fluoride Glass
(AIP Publishing, 1991-07-01)
The contribution of impurity ions to the total optical absorption of a heavy metal fluoride glass has been determined at 532 and 1064 nm. Four ZrF4-BaF2-LaF3-AlF3-NaF glasses were prepared from various purity raw materials. ...
Fabry-Perot Fiber-Optic Sensors in Full-Scale Fatigue Testing on an F-15 Aircraft
(Optical Society of America, 1992-02-01)
We report results from fiber-optic-sensor field tests on an F-15 aircraft mounted within a full-scale test frame for the purpose of fatigue testing. Strain sensitivities of the order of 0.01 _m/m have been obtained.