A physical-optics based concept for geometric and diffractive light shaping
Strasbourg, 23th of April, 2018, SPIE Photonics Europe
In physical optics light is represented by electromagnetic fields. A single field can exist, depending on its characteristics at different planes in space, in different zones, e.g. the far field zone. We therefore introduce the concept of geometric and diffractive zones of fields. Light shaping can be carried out by means of both smooth freeform surfaces and micro-structured surfaces (aka diffractive elements). Both types of light-shaping elements (smooth and micro-structured) may be applied in both types of zones (diffractive and geometric) of an electromagnetic field, depending on the desired effect. We describe and demonstrate design techniques for different applications of light shaping, including smooth and micro-structured surfaces, for different types of sources. The modeling is done vectorially in full and it therefore includes polarization and non-paraxial effects as well. The examples are demonstrated using the fast-physical optics software VirtualLab Fusion.