Linsenpfade

Linsenpfade is a German term used in optics to describe the trajectories that light rays follow as they pass through a system of lenses. In this sense, a Linsenpfad is the path from an object point through successive refractions to an image point, determined by the geometry of the lenses and the refractive indices involved. The concept is central to geometrical optics and forms the basis of ray-tracing methods used in lens design and optical engineering.

In practice, Linsenpfade are analyzed using Snell's law at each interface and the lens-maker equations. For many applications, the paraxial (small-angle) approximation is employed, where rays near the optical axis are treated as nearly straight lines that converge or diverge according to focal lengths. Beyond the paraxial approximation, aberrations such as spherical, coma, and astigmatism arise from deviations in Linsenpfade, guiding optimization of lens shapes, spacing, and coatings.

Applications include camera lenses, microscopes, telescopes, corrective eyewear, and other imaging systems. Modern design often uses computer-based ray-tracing to simulate Linsenpfade through complex multi-lens assemblies and to evaluate optical performance metrics such as MTF, distortion, and wavefront error.

The term is primarily used in German-language optical literature, where it may appear in discussions of lens design, ray tracing, and educational explanations of how light propagates through optical elements.