Light waveguides

The construction of the optoelectronic interface can be based on a silicon photodiode since analytical and reference wavelengths are from the visible and the IR regions, respectively. The signals can be filtered out by optical filters (then two photodiodes are required) or one photodiode can be synchronised with modulation waves of the LEDs used. Finally, silica optical fibres can be used as light waveguides. The choice between single fibre or bundle is determined by the application of the sensor. 

Studies of the waveguiding of light in multilayers of certain polymers showed that it is possible to propagate light with an attenuation that is still large compared to many other materials but small compared to other LB materials... 

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... 

Efficiency. Efficiency of a device can be reported in terms of an internal quantum efficiency (photons generated/electrons injected). The external quantum efficiency often reported is lower, since this counts only those photons that escape the device. Typically only a fraction of photons escape, due to refraction and waveguiding of light at the glass interface (65). The external efficiency can be increased through the use of shaped substrates (60). 

PT, PZT, PLZT nonvolatile memory, ir, pyroelectric detectors, electro—optic waveguide, and spatial light modulators sol—gel, sputtering... 

Fig. 2. Waveguide stmcture showiag the total internal reflection of light. The diameter, is 50 p.m for a standard multimode system, 62.5 p.m for a large...

The abihty of a waveguide to collect light is determined by the numerical aperture (NA) which defines the maximum angle at which light entering the fiber can be guided. 

Hafnium tetrafluoride [13709-52-9] is one component in the cladding layer of a proposed zirconium fluoride glass optical waveguide fiber composition which is expected to have a lower intrinsic light absorption than fused quart2 optical fiber (see Glass Fiber optics Fluorine compounds, inorganic-zirconium). 

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