Effect on Noise of Intensity-Axis Correction of Spectra Recorded with Charge-Coupled Device Detectors

Abstract

We have examined the effect of intensity-axis correction on noise in white light spectra recorded with charge-coupled device (CCD) detectors. Measurements were made with five detectors in Raman spectrometers. Detectors were both liquid-nitrogen and thermoelectrically cooled devices and one room temperature device. Both random and pattern noise have been considered. We used cross-correlation of noise sets to provide an indicator of a fixed pattern in the spectra and an assessment of the efficacy of the correction procedure in removing this pattern. For four of the five detectors intensity-axis correction provided a significant improvement in signal-to-noise ratio. Correction was particularly important for measurements made with lower-cost CCD detectors of the kind proposed for process control instruments.

Atomic Spectroscopy

“…All branches of optical atomic spectrometry benefited from the availability of high-quality CCD detector technology. The noise characteristics and implications as to their use in atomic spectrometry were investigated (67). The optimum adaption of Echelle spectrometers to high-quality CCDs was described by Haisch and Becker-Ross (68).…”

“…Size exclusion high-performance liquid chromatography in combination with ICP-TOFMS was investigated by Infante et al exposed carp was obtained with species-unspecific spiking by postcolumn addition of the enriched isotopes 65 Cu, 67 Zn, and 106 Cd. Speciation differences were encountered between control and Cdstressed carp, indicating that quantitative speciation studies might be useful for ecotoxicological and biomonitoring purposes.…”

Wavenumber Calibration of CCD Detector Raman Spectrometers Controlled by a Sinus Arm Drive

“…Yet another key element to good calibration of dispersive Raman instruments that needs to be mentioned is the spectral intensity response of the instrument (also called the white light calibration) [18], [37], [38], [39], [40] . With intensity-axis correction even low-cost CCD detectors can be used to get Raman spectra with signal-to-noise ratios approaching those obtainable with the most expensive "scientific" ones [40] . Large errors owing to the inability to reposition the spectrometer precisely and to temperature fluctuations were found [6], [9] .…”

Evaluation of a dispersive Raman spectrometer with a Ge array detector and a 1064nm laser for the study of explosives

“…Among these approaches, dispersive Raman spectrometry with NIR excitation at 830 nm and a CCD array detector offers broad applicability when high sensitivity and minimal fluorescence with many explosives is required. In addition, dispersive Raman spectrometers are readily coupled to fiber-optic probes [23,27], require no moving parts [23,28], and incorporate field transportable technology [22,23,29,30].…”