Imaging with an optical microscope system is influenced by aberrations generated by the components it consists of. For example spherical aberrations, coma and axial chromatic aberrations as well as lateral chromatic aberrations and astigmatism disturb the image. Fortunately, there are measures to minimize these influences.
Classically, manufacturers tried to eliminate aberrations at the component that was generating it. Over the years philosophy changed and optics developers started to consider the microscope as a whole system. In 1992 Leica Microsystems turned this vision into a name – the DELTA system, which was a universal infinity optics system for transmitted and incident light microscopy. It allowed the unrestricted modular use of all optical contrasting techniques for all users .
Continuing this system philosophy, the