Light-guide

The MCB tubes suit ideally into a concept of using glass capillary X-ray light guides to increase radiation intensity at the measurement spot. 

The most recently introduced optical teclmique is based on the retardation of light guided in an optical waveguide when biomolecules of a polarizability different from that of the solvent they displace are adsorbed at the waveguide surface (optical waveguide lightmode spectroscopy, OWLS) [H]. It is even more sensitive than ellipsometry, and the mode... 

Figure4b. Cell in microwave cavity (l)resonator, (2) waveguide, (3) cylindrical exit, (4) electrochemical cell, (5) working electrode, (6) electrolyte, (7) counter-electrode, (8) contact wire to working electrode, (9) opical light guide.

Cleaning fabrics, quartz rods for light guide fibers, residues in microelectronics Removal of monomers, oligomers, and solvent from polymers Fractionation... 

Another early fiber optic refractive "sensor" was the one for measurement of temperature and salinity variations of sea water31. The sensing region consisted of a partly uncovered light guide. It detects salinity variations in water of known temperature, and temperature variations in water of known salinity with an accuracy of +/- 2 g/L and 1 °C, respectively, at NaCl concentrations of 300 g/L. 

Important parameters, characterizing fibre properties, are the attenuation a and numerical aperture NA. The attenuation (Equation 1) represents optical losses caused by absorption or scattering of the light guided through the unit fibre length. It is given by ... 

Figure 1. Schematic diagram of specially designed fixtures used to measure, in situ, the evolving rheological properties during UV curing. The sample is placed between the two quartz plates and the incident UV radiation exiting the liquid light guide is reflected by the mirror through the plates and onto the sample.

Schelle, B. Dress, P. Franke, H. Klein, K. F. Slupek, J., Physical characterization of light guide capillary cells, J. Pkys. D Appl. Pkys. 1999, 32, 3157 3163... 

Indeed these qualities have been developed since the mid-Century so that in a particular segment of the information industry such as telephones and communications, our volume of synthetic polymers used annually exceeds that of any other class of materials, although the actual tonnage of metallic and inorganic matter still leads. For the world of tomorrow, we find microelectronics, thin film circuitry and systems and, especially now photonics, with lasers and light guides, to be dominant components. All of these strongly use polymers, for their special physical-chemical as well as familiar mechanical and electro-optical qualities. 

Mechanical Factors in Polymer-Coated Light Guides... 

Figure 18. Method of coating ultratransparent light guide fibers of silica with polymer films for strength and stability.

Figure 19. Influence of UV radiation as polymerization agent on the subsequent total photon attenuation in silica fibers, as a function of wavelength in nanometers. When no absorption of the UV is arranged lowest losses are assured. (The loss expressed in decibels per kilometer is a modern figure of merit for light guide...

Figure 20. Limitation of excess microbending loss of photon transmission through light guides, as a function of relaxation modules of the stabilizing polymer coating.

As evidence of light guide fiber stabilization and control through processing refinement, plot of frequency of failure against the tensile strength (in hundreds of thousands pounds per square inch) shows extraordinary uniformity for the control system compared to wide distribution of failures from surface defects and other variations in a conventional fiber... 

Electronics bi-oriented films, metallized films, light guides and diffusion plates for LCDs, semiconductor containers. .. 

Surface fluorescence of NADH/NADPH can be recorded continuously with a DC fluorimeter and correlated with changes in experimental conditions. A mercury arc lamp (with a 340-375 nm filter in front) is used as a hght source for fluorescence excitation. The fluorescence response of reduced NADH/NADPH was measured at 450-510 nm. The DC fluorimeter and the Hg arc lamp are connected to the kidney by a trifurcated fiber optics light guide. NADH/NADPH fluorescence emission can be corrected for changes in tissue opacity by a 1 1 subtraction of reflectance changes at 340-375 nm from the fluorescence. To determine NADH/NADPH redox state of the total surface area of kidney cortex and to evaluate whether certain areas were insufficiently perfused, fluorescence photographs of the total surface area were taken. The study demonstrated that the surface fluorescence method is simple and provides specific information about the mitochondrial oxidation-reduction state. 

Scientists are currently using LB film assemblies as solutions to problems in diverse areas such as microlithography, solid-state polymerization, light guiding, electron tunneling, and photovoltaic effects. In the case of such films as Mg stearate, if a clean glass slide is dipped through the film, a monolayer is adsorbed on the downstroke. Another layer is adsorbed on the upstroke. Under careful conditions,... 

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