Folded light source: a technique for compact and efficient automotive lighting

Abstract

Segmented reflectors are frequently used in automotive lighting applications. Extended light sources are one of the limiting factors on the compactness of segmented reflectors. We propose the technique of folding the light source for achieving highly compact reflector designs while improving their efficiency. We then use the macrofocal approach to design legal low-beam reflectors based on the proposed folded light source technique. We show that our method can deliver 51.2% more optical flux, which results in a significant improvement in the efficiency equal to 26.2%. This technique would allow optical engineers to design more compact and energy-efficient products for automotive headlamps and for general lighting applications.