Fiber coupling

Pigure 10 shows the typical commercial performance of LEDs used for optical data communication. Both free-space emission and fiber-coupled devices are shown, the latter exhibiting speeds of <10 ns. Typically there exists a tradeoff between speed and power in these devices, however performance has been plotted as a function of wavelength for purposes of clarity. In communication systems, photodetectors (qv) are employed as receivers rather than the human eye, making radiometric power emitted by the devices, or coupled into an optical fiber, an important figure of merit. 

Generally, these exists a tradeoff between speed and output power in these devices. The data for fiber-coupled devices are based on emission into a 50/125-//m fiber, except for AlGalnP which is for 1-mm plastic optical fiber coupling. 

Linearly polarized, near-diffraction-hmited, mode-locked 1319 and 1064 nm pulse trains are generated in separate dual-head, diode-pumped resonators. Each 2-rod resonator incorporates fiber-coupled diode lasers to end-pump the rods, and features intracavity birefringence compensation. The pulses are stabilized to a 1 GHz bandwidth. Timing jitter is actively controlled to < 150 ps. Models indicate that for the mode-locked pulses, relative timing jitter of 200 ps between the lasers causes <5% reduction in SFG conversion efficiency. 

Fiber laser guide star systems. It is now widely appreciated that the heat- dissipation characteristics of fibers, coupled with the high efficiencies demonstrated (> 80%) and excellent spatial mode characteristics, make fiber lasers a preferred candidate for many high power applications. Based on these features, fiber laser technologies would provide a compact, efficient, robust, turnkey laser source, ideally suited for LGS applications. 

The enhancement techniques briefly described in this section are just a few of those that can be used to make cavity-enhanced evanescent-wave chemical detection even more sensitive. The use of dielectric microresonators with tapered-fiber coupling enables performance that is difficult to achieve in other configurations, while minimizing the sensor size. 

Humphrey, M. J. Dale, E. Rosenberger, A. T. Bandy, D. K., Calculation of optimal fiber radius and whispering gallery mode spectra for a fiber coupled microsphere, Opt. Commun. 2007, 271, 124 131... 

Chiba, A. Fujiwara, H. Hotta, J. Takeuchi, S. Sasaki, K., Fano resonance in a multimode tapered fiber coupled with a microspherical cavity, Appl. Phys. Lett. 2005, 86, 261106... 

Moser, W. R., Reaction Monitoring by High-Pressure Cylindrical Internal-Reflectance and Optical-Fiber Coupled Reactors. In Moser, W. R., Slocum, D.W. (Eds.), Homogeneous Transition Metal-Catalyzed Reactions, American Chemical Society, Washington DC, 1992, Advanced Chemistry Series 230, p. 5. 

More recently Ghiggino and co-workers(32) have applied laser scanning confocal fluorescence lifetime microscopy to the study of polyvinyl alcohol films containing rhodamine B (650 nm emission) and cresyl violet (632 nm emission). Synchronously pumped dye laser excitation and APD detection were used with optical fiber coupling. A schematic diagram of their apparatus is shown in Figure 12.5. 

Design and selection of the sample interface is vital to provide the best-quahty data for an analysis. The sample interface may be located in the sample cavity of a spectrophotometer, as in the cases of laboratory cuvettes, vials, and flow cells. The sample interface may also be fiber-coupled and located closer to the process. Fiber-optic sample interfaces include flow cells, insertion probes, and reflectance probes. 

Major, A., Cisek, R., and Barzda, V. 2006. Femtosecond Yb KGd(W04)(2) laser oscillator pumped by a high power fiber-coupled diode laser module. Opt. Exp. 14 12163-68. 

Supported hollow fiber coupled transport pilot plant installed at Wyoming uranium mill -1983... 

Figure 11.12 Schematic of a three-stage feed-and-bleed hollow fiber coupled transport concentrator [49]...

Figure 11.13 The effect of replenishing a hollow fiber coupled transport module with fresh complexing agent. Membrane, polysulfone, hollow fiber/Kelex 100 feed, 0.2 % copper, pH 2.5 product, 2% copper, 100 g/L H2S04 [49]...

Palais, J.C., (1980), Fiber coupling using graded-index rod lenses , Appl. Optics., 19(12), 2011-2018. 

A 7] The fiber-coupled spectrometer is actually designed for applications with hand-held devices. A combination of micro injection molding and an electroforming process allows the production of a high-performance but low-cost device. The optical grating is, for example, replicated in plastic to reduce costs. 

In one report, the detection optical fiber (coupled to a blue LED light source) and the microavalanche photodiode were both embedded in a PDMS chip to detect proteins [692]. 

Light scattering measurements were made with an ALV DLS/SLS 5022F goniometer equipped with optical fiber coupling and an avalanche diode, with a 22 mW HeNe laser working at 632.8 nm and an ALV 5000E multi-tau correlator. 

Library of Congress and others started having problems with paper fragility in many of their so-called permanent reference books. Subsequent investigations determined the reduced permanence resulted from a combination of two factors, the use of wood as a source of cellulose fiber coupled with acid papermaking and sizing systems. 

Fig. 7.29 Schematic design of the DAX assembly. The PDV veiocity-probe that tracks the witness foil acceleration is fixed to the end of a 100 mm long acrylic extension and fiber coupled to the PDV detection hardware.

Fiber-coupled microscope Polyethylene terephthalate fibers 35... 

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