PROJECTOR TYPE HEADLAMP OF MAXIMIZED LIGHT COLLECTING EFFICIENCY

摘要

An improved light collecting efficiency in a projector type automotive headlamp (200) is achieved by including a curved mirror (250) to re-direct light otherwise absorbed by a rear surface of the blocking cut-off shield (222) in "low beam" operating mode of the headlamp (200). When the shield (222) is moved to a second non -blocking position, a mirror segment conforms to the curved surface (250) of the substantially ellipsoidal reflector (210) to maximize lumen output in "high beam" operating mode of the headlamp. In addition, auxiliary mirror segments (270,272) may be used to provide a more complete substantially ellipsoidal reflector configuration that maximizes the light collection efficiency. Preferably, the cap holder (300) is purposefully offset in order to position the centerline (CLA) of the bowed arc of the arc discharge light source (202) in alignment with the optical axis (OA) of the optical system in order to maximize light collection efficiency.