Vehicular headlamp with heat-resistant coated filter screen - facilitates conduction of heat away from edge of screen defining boundary between bright and dark regions

摘要

A gas-discharge lamp (2) is positioned at the focus (5) of an ellipsoidal reflector (1) directing the beam through a plano-convex lens (3) in a tubular frame (8). The lower part of the beam is screened by a sheet of transparent filter material with a layer of heat-resistant ceramic or metal at the edge region corresp. to the boundary of the beam. The filter may be opaque to visible, and transparent to ultraviolet light. ADVANTAGE - Screen can withstand high temp. even if material of filter itself is insufficiently heat-resistant.