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Abstract

Noise in the common kinds of infrared spectra in use today is considered. Statistics are employed to suggest modified spectra that have more desirable noise properties. A computer-spectrometer system for infrared spectroscopy is described with the novel feature that the computer modifies the scanning characteristics of the spectrometer as the data are acquired, permitting complete flexibility in programming the spectrometer's task. This system is able to control the spectrometer in the ways required to produce the modified spectra. The nature and operation of the electronic interface between the computer and the spectrometer are described together with the basic characteristics of the computer software used to program it. Several examples of the modified spectra are shown. Significant improvement in spectrum quality and run time is seen.

Keywords

Computer applications Infrared Solution structure

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References

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Note that the best value of

is not an average defined by

where A_i = – log T_i. The difficulty with the average value as defined just above is that it does not equal – log T̄, i.e., its use does not lead to the satisfaction of the basic expression of theory [Eq. (2)]. While the difference between the average absorbance defined above and – log T̄ is not large in the upper portion of the transmittance range, the difference increases as T̄ falls from its maximum value near 1 and becomes large when the noise in single measurement of the transmittance is no longer much smaller than T̄.

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10.

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A Computer-Spectrometer Interactive System for Infrared Spectroscopy

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References