Infrared spectrum measuring apparatus adapted for measuring the absorption of infrared radiation by a liquid sample utilizing a total reflection phenomenon of light

摘要

Infrared radiation is incident on a total reflection plane of a prism and penetrates a liquid sample through a metal layer put between the total reflection plane and the liquid sample in close contact therewith whereby the infrared radiation is partially absorbed by the liquid sample. Alternatively, the liquid sample may be put between the total reflection plane and the metal layer in close contact therewith so that part of the light penetrates the sample from the prism through the total reflection plane to interact with the metal layer and then is caused to reenter into the prism whereby it is partly absorbed by the liquid sample. The metal layer is for enhancing the intensity of the electric field component of the infrared radiation. The incident angle of the infrared radiation on the total reflection plane is so set that the partially absorbed infrared radiation is total-reflected. The total- reflected infrared radiation is detected by a detector so as to obtain an absorption spectrum of the liquid sample by the infrared radiation.