Patent ID: 6527425
Filing Date: 2003-03-04
Classification: F21S

Abstract:
A method for determining a reflective surface of a reflector for a headlamp comprising the steps of:providing a light source on an optical axis for emitting light; providing a reflector about the optical axis for reflecting the light; providing a flat lens about the optical axis and opposite to the reflector for transmitting reflected light therethrough; determining a provisional reflective surface of a B-spline surface of the reflector, so that first light reflected by the provisional reflective surface transmits through the flat lens to project as a first brightness distribution pattern in conformance with a reference brightness distribution pattern; replacing the flat lens with a curved lens for transmitting second light reflected by the provisional reflective surface through the curved lens to project as a second brightness distribution pattern; determining a difference between the reference brightness distribution pattern and the second brightness distribution pattern; and determining a primary reflective surface of a B-spline surface of the reflector, so that third light reflected by the primary reflective surface transmits through the curved lens to be substantially parallel with said first light and to project as a third brightness distribution pattern to substantially cancel said difference.