Abstract:
A diffuse reflector of radiation in the near and mid infrared regions includes (i) an assembly that has a reflecting element and a diffusing element that is made of one or more layers of calcium fluoride, sapphire, or alumina; or (ii) a diffusively reflective surface configured as a metallic layer with a rough surface. The diffuse reflector can be incorporated into systems for measuring properties of sheet materials and particularly into optical sensors that include a measurement window configured with one or more of the diffuse reflectors that cause incident radiation from a sensor light source to be diffused and reflected a plurality of times within a layer of material before being detected by the sensor receiver.
Abstract:
A system (100, 300) includes a signal source (126, 326) that provides a first signal for measuring a gas content of a liquid sample. The system also includes an analyzer (128, 328) that determines the gas content of the liquid sample using a measurement of a second signal, where the second signal is based on the first signal. The system further includes an apparatus with a walled structure (106, 306) having a cavity (108, 308). The apparatus also includes a piston (110, 310) that pulls the liquid sample into the cavity and pushes the liquid sample out of the cavity. The apparatus further includes at least one measurement window (130-132, 330) having at least one inner surface exposed within the cavity. The at least one measurement window receives the first signal from the signal source and provides the second signal to the analyzer. The piston could also clean the at least one inner surface, and the piston can include a reference material (116, 316) for calibrating the analyzer.