Dark field illumination
With dark field illumination (see also direct incident light), the light source is positioned in such a way that direct reflections from a completely smooth surface do not hit the lens. This is achieved by shallow lateral incidence of light. This type of lighting gets its name from the fact that a completely smooth, reflective surface then appears dark.
See also the opposite bright field illumination.
Principle and example(ARCUS-130-SL) of dark field illumination (source principle: Vision Doctor).
