In optical component development, and especially for plastic lens systems, it is critical that material properties be known as precisely as possible – properties such as dispersion, or the frequency-dependent refractive index. But these material properties depend on such factors as manufacturing processes – on injection molding parameters such as temperature and pressure, for instance. Since quality requirements are very high in the mass production of smartphone cameras, optical sensors for automobiles, and the like, material properties resulting from temperature and production parameters must be monitored.

The new method ascertains dispersion (refractive index wavelength dependency) with a simplified setup that features no moving parts and does not even have a wavelength scan. The resulting precision is lower than that of current commercial refractometers, but the movement-free setup and high measurement speed allow parameter studies that could not previously be achieved. Further information is available in the patent granted. (DE 10 2020 109 742 A1).