A compact bike head lamp design based on a white LED operated at one watt

A design of a compact bike head lamp meeting the K mark regulation based on a white LED by Cree XP-C is presented. The proposed design contains three parts, one is a parabolic mirror, another is a flat mirror and the other is a lens. The design performed a contrast of 66.7 across the cut-off line by the K-mark regulation, and a prototype fabricated by a simple CNC machining was measured a contrast of 12.4 across the cut-off line. The successful design requests the LED operated at only 1 W, and it enables an user to operate the lamp longer with energy saving.

► Applying 1W LED for bike head lamp meeting the K mark regulation. ► A special design for getting high-contrast ratio across the requested cut-off line. ► A compact prototype demonstrated the successful design.