Abstract: A magnetic field controller has been developed, which allows magnetic deflection of the arc of an alternating current high intensity discharge (HID) lamp. The controller consists of a driving circuit and an electromagnet. The system delivers a fast switching magnetic field, which can follow the alternating current signal of an alternating current HID ballast. The method minimizes the electromagnet's inductance and uses fast reacting ferromagnetic materials (Ni--Zn ferrite). To achieve the required magnetic field, a current amplifier was developed to pick up the signal from the alternating current ballast and drive the electromagnet with up to two amperes. The alternating magnetically deflected HID lamp system allows the use of magnetic deflection for alternating current HID lamps. A vehicle headlamp system can achieve multiple beam functions (day light running, low beam and high beam) of a headlight system with only one alternating current lamp.

Abstract: A lamp assembly includes a lamp capsule having a tubular lamp envelope, and a reflector disposed around the lamp envelope. The reflector defines an aperture for emission of light from the lamp capsule. The reflector has a reflecting surface facing the lamp envelope. The aperture has a dimension transverse to the longitudinal axis of the lamp envelope that is less than the diameter of the lamp envelope. The reflecting surface preferably has a diffuse reflecting characteristic. The lamp capsule may be a low pressure discharge lamp, such as a neon lamp. The lamp assembly may, for example, be used as a center high mount stop light in a vehicle.