Detectors optimization

A mid-infrared absorption instrument generally consists of a Fourier transform design with the same basic components as noted above for the Fourier transform near-infrared spectrometers (broadband light source, Michelson interferometer, and detector optimized for the mid-infrared spectral region.)... 

Here m is a coelScient that parameterizes a detector-wavelength combination. For example, a CCD detector optimized for copper radiation used m = 0.1763. One optimized for molybdenum radiation had m = 0.3274. No derivation of this formulation has to date been published. 

The essentials of the FT-IR spectrometer are shown in Figure 3.11 (Koenig, 1984). Commercial instruments have the source, beam splitter and detector optimized for maximum SNR in the spectral region of interest (Table 3.1). 

Minimal system requirements are a GC equipped with electronic pneumatic control (EPC), off-the-shelf capillary columns, split/splitless or on-column inlets, standard detectors optimized for capillary columns, and a fast acquisition data system. At any time, users can switch from fast GC back to the original method without major difficulties, or optimize new methods to meet new analytical demands. 

Continued development of pixelated detectors optimized for the highbrightness of synchrotron sources and further improvements beamline sources should yield ever more capable wide-held rapid imaging fadhties and instrumentation. 

Fig. 2.48 Spectral current responsivity and specific detectivity of a HgCdTe RCE detector optimized for 10.6 pm...

The presented results are valid for a mercury cadmium telluride n v detector optimized for 10.6 pm. Figure 3.19 shows the calculated dependence of theoretical g-r noise current on detector bias current. Calculation parameters are shown in the figure. For low bias currents noise practically does not increase with the current, but this is the region where the exclusion effects are practically useless. A strong increase appears for higher bias values, while at still higher bias currents theoretical noise reaches saturation. 

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