Infrared absorbance detector:

Infrared detector cells are similar in construction to those used with uv radiation except that windows are made of sodium chloride or calcium fluoride and the cell lengths range from 0.2 to 1.0 mm with volumes 1.5 to 10 µ L. The simpler ir instruments can be operated at one or more single wavelength settings. Instead, the spectra for peaks can be scanned by stopping the flow at the time of elution. Two types of ir detectors are used. The first is with wavelength scanning being provided by three semi circular wedges with a range of 2.5 to 14.5 µ m or 4000 to 690 cm^-1. The second type of ir detector is based upon Fourier transform (FT) instruments which can be attached with HPLC detectors.