Fiber optics, wavelength transmittance

Apparatus. The fiber optic photometer is similar to the instrument used in earlier work (2). It includes a tungsten-halogen source, a photomultiplier detector, interference filters for wavelength selection and a bifurcated fiber optic bundle 3 mm in diameter at the common end. In this study, excitation filters had peak transmittances at 420 and 480 nm and the emission filter had peak transmittance at 520 nm. The bandwiths at half-maximum transmittance were 9.4, 8.2 and 8.6 nm for the 420, 480 and 520 nm filters, respectively. An automated filter wheel allowed for rapid switching from one filter to another. 

Williamson (continued) TempMatic 4000, FiberView 5000, 500, 700, and 1000 series, TransTemp series Various models ranges from 30-2500°C 2-wire, fixed focus transmitters 2-wire, fixed focus, single-wavelength and ratio pyrometers some fiber optic coupled models. 

For TOLAS measurement in PEMFCs, the laser diode as the transmitter and the photodiode as the detector are used. In a typical experimental setup with TOLAS as Basu et al. reported, the laser beam from the distributed feedback diode (DFB) laser at a wavelength of 1470 nm was split using a bifurcated optical fiber. One leg... 

With quartz fibers it is easier to lead the optical emission into the spectral apparatus, however, it should be mentioned that the transmittance decreases seriously below 220 nm. This may give rise to detector noise limitations for analytical lines at lower wavelengths. 

Similarly, the development of extremely higjr purity silica fibers and new photonic materials that provide laser transmitters and receivers have revolutionized landline communication systems. Other developments in photonic materials have made possible highly efficient LEDs in all colors that are being used in traffic lights and other displays. Very small efficient short wavelength solid-state lasers have also made possible massive optical storage which enabled the development of CDs and DVDs. 

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