Design of an energy-efficient marine signal light based on white LEDs

In this paper, we proposed and demonstrated a new design of marine signal light based on a phosphor-converted white light emitting diode. The light pattern was shaped in the vertical and horizontal directions, respectively, by a collimating total internal reflection lens with cylindrical lens array and a slanted shoulder to fit the requirement in the regulation. The vertical intensity distribution was collimated to 9° through an appropriate volume of the total internal reflection lens to fit the etendue of the light source. The horizontal intensity distribution was shaped with a cylindrical lens array to enlarge the horizontal to the divergent angle, and a specially-designed slanted shoulder to reduce the total internal reflection loss and extend the divergent angle from 45° to 67° with a flat-top shaping light pattern. As a result, only five pieces of the light emitting diode module around 6W is enough to build up a marine signal light to reach a distance of 8 nautical miles.