Effect of charge traps on Raman spectroscopy using a Thomson-CSF charge coupled device detector

Charge coupled device (CCD) detectors have seen increasing use in analytical spectroscopy in recent years. One of the more popular scientific-grade CCD detectors on the market is the Thomson-CSF TH7882CDA. However, the TH7882 CCD suffers from a phenomenon known as a charge 'trap' associated with the interface between the serial and parallel registers. This trap causes absorption, emission, and mixing of charge passing through this interface depending in a complex manner upon both the quantity of charge in the trap and the quantity of charge entering the trap. The effect of this charge trap on the resulting spectral response for very low-light-level applications is demonstrated here. It has been shown that for three of the four types of cellulose studied, an infrared analysis technique has been developed which can determine whether embrittlement of the cellulose has occurred. This technique was successfully used in the search for new embrittling reagents.