Comparison of Dual Focus Collector Schemes for Fiber Systems 970254
The development of efficient, multi-output High Intensity Discharge (HID) light sources is important for driving fiber systems in automotive applications, in particular for headlamps. Such systems must collect a large fraction of the light from the HID source while efficiently coupling the light into large core light pipes.
An earlier paper  showed how multifocus optical systems can efficiently split the light evenly between separate output ports. Multifocus systems were shown to be more efficient than a mixing rod approach, especially for the case of two ports. In the case of dual output systems, many more cases need to be considered. To facilitate the investigation, a state-of-the-art optical analysis/design program was employed to demonstrate the tradeoffs between six different dual focus geometries. A novel dual ellipse approach is presented.