Refraktionsfel

Refraktionsfeld, in optics, refers to the spatial distribution of refracted light directions after light interacts with a medium or an optical element. It describes how the refractive power is arranged across a pupil, aperture, or field of view, and how this arrangement influences the angles at which rays emerge from the surface or traverse a region with varying refractive index.

The concept rests on the local application of Snell's law. For a given incident ray, the refracted angle depends on the local refractive index and the surface geometry at the point of interaction. In simple lenses, the refraktionsfeld can be approximated by considering a smooth, continuous change of direction across the aperture. In gradient-index (GRIN) materials, where the refractive index changes gradually inside the material, the refraktionsfeld arises from the index gradient rather than from discrete surfaces.

Computationally, the refraktionsfeld is often obtained through ray tracing or optical design software. Rays are propagated through the system, with refraction computed at each interface or along the index gradient. The resulting field of ray directions can be visualized as a map of angular deviations or as a set of refracted coordinates across the image plane. This field is closely related to, yet distinct from, the wavefront; it emphasizes the directions of rays rather than their phase.

Applications of the refraktionsfeld include lens design and optimization, where engineers seek to minimize field-dependent aberrations such as spherical aberration, coma, and astigmatism. It is also relevant in imaging systems, cameras, microscopes, and projection devices, as well as in GRIN optics and advanced optical instrumentation where precise control of ray directions across the field is required.