SEALED BEAM TYPE REFLECTIVE LAMP

摘要

A sealed beam type reflective lamp has an envelope comprising a front lens and a reflector on the inner surface of which is formed a metal reflective film, and a tungsten coil filament arranged inside the front lens. The lamp has excellent converging effect and its light beam does not spread even if the filament is brought closer to the front lens. The front lens consists of a central circular lens element and a plurality of concentric ring-shaped prism elements. The inner surfaces of these prism elements define a stepped inner surface of the front lens. An angle formed by an inner surface of the prism lens element and the central axis of the lamp is greater than that of the prism lens element situated outward thereof. The step difference of the inner surfaces of the adjacent prism lens elements is 0.6 mm or less.