Infrared measuring device, especially for the spectrometry of aqueous systems, preferably multiple component systems

The invention relates to an infrared measuring device, in particular for the spectrometry of aqueous systems, comprising at least one measuring unit, in particular a measuring cell, comprising at least one ATR body and at least one infrared light source, wherein the measuring unit contains at least one ATR body, the at least two flat, comprises substantially parallel boundary surfaces which is transparent to the measuring radiation and which has a refractive index which is greater than that of an adjacent to at least one boundary surface to be examined medium, in particular greater than or equal to 1.5, wherein the IR measuring radiation on at least one of the planar , parallel boundary surfaces of the ATR body is at least six times attenuated total reflectable.