Aspheric lenses are of increasing importance in today’s optical industry. In a multitude of different areas of application single aspheric lenses are used instead several spherical lenses to build compact imaging systems. Thereby, the size and the weight of the systems are considerably reduced.
These systems have to be checked not only for their imaging properties after completion of the production process, but also after individual steps in the production process during the assembly.
In most of the cases conventional methods cannot be used for this kind of testing. Although e.g. the measurement of the modulation transfer function is a well-established method for fast and accurate quality inspection of entire objectives it has its limitation for non-imaging systems.
In contrast to this, Shack-Hartmann sensors are able to measure a very broad range of spherical and aspherical lenses as well as partially or fully assembled objectives due to their large dynamic range. In addition the high measurement frequency allows for real time testing and analysis.