High-performance LED street lighting using microlens arrays.

An efficient LED lamp that illuminates the street with high quality is presented. The luminaire shows high optical efficiency, high optical utilization factor, low glare, and illuminates the street with high uniformity. The concept is simple but effective: a cluster of LEDs with TIR lenses are put inside a reflective box, which is covered with a microlens sheet; the reflective cavity improves efficiency by light recycling; each TIR lens collimates the LED light for the microlens array; and the microlens sheet uniformly distributes light only into the street. We verify its feasibility by Monte Carlo ray-tracing for the main types of road lighting arrangements: central, zigzag, and single-side pole positions.