Charge Transfer Device Detectors and Their Applications to Chemical Analysis

In the last 20 years, charge-transfer device detectors (CTDs) have evolved from small analog shift registers to the most common imaging detector available today. CTDs are a category of array detectors that include the charge-coupled device (CCD) and the charge-injection device (CID). Modern devices can have a peak quantum efficiency in excess of 80%, read noises of ≤ 5 e, dark count rates of 1 e/h per detector element and formats as large as 4096 by 4096 elements. The operation and characteristics of CTDs are described, with the readout methods useful in scientific applications emphasized. The application of CCDs and CIDs to a number of fields of chemistry are reviewed, including the fields of Raman spectroscopy, molecular fluorescence, molecular absorption, atomic emission and X-ray detection. Trends in the application of CTDs and their expected impact on a number of areas of chemical analysis are featured.