Infrared microspectroscopy. II.

An improved infrared microspectrometer is described. A figure of performance or merit for infrared spectrometers using certain types of specimens is suggested. An experimental value is given for this performance figure for the instrument now in use in our laboratory. The increased performance of the microspectrometer may be observed in the spectral data shown for typical specimens.Spectral resolving power and sample size requirements for infrared microspectroscopy are considered for typical organic chemical substances. It now appears that for many applications the limiting factor on sample size is the difficulty in the preparation and handling of the sample rather than the performance of the instrument.