Commercial charge-coupled device detectors

Bioluminescence detector Charge-coupled device Contactless-conductivity detector Capillary electrophoresis Capillary electrophoresis-Electrochemistry Collision-induced dissociation Chemiluminescence detector Sodium chlorate-nitrobenzene Commercial off-the-shelf (U.S. Army) Cold Regions Research and Development Center Croatian Mine Action Center Council of Scientific and Industrial Research,... 

The classical silicon photodiode linear array manufactured by Reticon was the first detector marketed successfully. Similar solid state linear array detectors based on charge coupled devices, or charge.injection devices may also be of interest. Typical of the families of detectors, the Reticon detectors are built in a number of elements/array sizes. Commercially available units have anywhere from 128 to 1024 elements/array. Each individual element in the array is 1 x 1 mil to 1 x 100 mil in area, and are spaced on approximately 1 mil centers. The spectrometer system discussed in this article was built using Reticon-type devices. 

Major technological and scientific innovation in the past 10 to 15 years has significantly broadened the applicability of Raman spectroscopy, particularly in chemical analysis. Fourier transform (FT)-Raman, charge-coupled device (CCD) detectors, compact spectrographs, effective laser rejection filters, near-infrared lasers, and small computers have contributed to a revolution in Raman instrumentation and made routine analytical applications possible. An increase in instrumental sensitivity by factors as large as 10, plus decreases in both interferences and noise resulted from this revolution. The number of vendors of Raman spectrometers increased from 3 to 12 over a 10-year period, and integrated commercial spectrometers led to turnkey operation and robust reliability. 

Several difl ereni types of cllipsometers arc available commercially. The earliest type was the null-type ellipsometer in which a circularly polarized incident beam was reflected off the sample surface onto an analyzer. The incident-beam polarization stale was chosen by a polarizer and compensator so that linearly polarized light was obtained after reflection. 1 he analyzer was then rotated until it was perpendicular to the polarization axis of the light coming from the sample as indicated by a minimum in the light iniciisiiy. Some instruments today still use the null principle, bui they are computer controlled and have charge-coupled-device (C (-I)f cameras as detectors. 

In the atomic emission detector (AED), the effluent from the GC column is introduced into a microwave-induced plasma (MIP), an inductively coupled plasma (ICP), or a direct current plasma (DCP). The MIP has been most widely used and is available commercially. The MIP is used in conjunction with a diode array or charge-coupled-device atomic emission spectrometer as shown in Figure 27-12. The pl ma is sufficiently en-... 

Charge coupled detectors These devices are not yet commonly available in commercial instrumentation for analytical spectrophotometry although they are used in applications in inductively coupled plasma atomic emission spectrometry. However, they have found extensive application in imaging and astronomical applications. Essentially they are two-dimensional photodiode arrays which allow many spectra to be acquired in one readout. A typical array sensor is shown in Figure 9. 

---