The Double-Beam Recording Spectrophotometer

Since this is a book concerned primarily with applications, no further details are given concerning instrumentation. The reader is referred to Alpert et al. (1970), in which are discussed an optical diagram of a double-beam spectrophotometer operating variables (resolution, photometric accuracy) components of infrared spectrophotometers (sources, types of photometers, dispersing elements, detectors, amplifiers, and recorders) special operating features, such as optimization of scan time and available instruments and their specifications. The books by Martin (1966), Conn and Avery (1960), and Potts (1963), and the chapter by Herscher (1966) are also recommended for details on some of these topics. 

The potentialities of multiple-scan interferometers have been explored by Low and coworkers, who in several papers have covered the subjects of emission spectra of pesticides in the microgram range (Coleman and Low, 1966), human skin (Low, 1966), reflectance spectra of minerals (Low, 1967), and absorption spectra of gas-chromatographic fractions (Low and Freeman, 1967). More recently Low (1969) has also discussed Fourier transform spectrometers. 

---