Abstract: An apparatus for optical measurement of substance concentrations has at least one transmitter arranged in or on a housing and at least one receiver for optical radiation, and a deflection device, which is at a distance from the at least one transmitter and the at least one receiver and is arranged within the substance when the apparatus is being used correctly, for deflection of the optical radiation from the at least one transmitter to the at least one receiver. The distance between the deflection device and the at least one transmitter and/or the at least one receiver can be varied by means of an adjusting device.

Abstract: An apparatus for analyzing a product to be analyzed which is located in a receptacle provided with a coupling element, in particular for photometric or spectrophotometric analysis of powder, bulk material, granular material and similar, is provided with a docking element for sealing connection to the coupling element, and with a measuring probe which is arranged in a probe housing and is provided with at least one radiation and light measuring element, at least one measuring window, which is arranged in the beam path and is arranged in a wall of the probe housing, and with at least one detection element for the analysis. The probe housing with the measuring probe is designed and guided displaceably in such a way that at least a part of the probe housing in which the measuring window is located can be inserted into the receptacle for the analysis.