Light-emitting diodes (LEDs) have been widely used in road lighting. This study investigates the optical design of a high-mast luminaire based on four chips-on-board LED light source modules and applies it to road lighting. The model of the high-mast luminaire is built with Solidworks, and then the optical simulations are analysed by Tracepro and Dialux. We also make a physical prototype of the high-mast luminaire to test its performance in practice. The illuminance distribution of the test area is nearly rectangular. The interior of the rectangle forms a smaller highlighted rectangular illumination area with uniform illumination. The outer edges of the rectangular illumination area will overlap the outer edges of the illumination area of other high-mast luminaires. The desired illuminance distribution and the uniform illumination can be obtained. Both the simulations and the experimental results meet the requirements of road lighting standards and the high-mast lamp can even achieve a better optical performance.

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This paper provides a design method for a light-emitting diode front fog lamp system based on a freeform surface and an improved quadric surface. First, a light-receiving reflector is used to converge the light-emitting diode beam to form an equivalent lighting point. Then, the relationship between the point and the light pattern on the work surface is calculated, and the freeform surface is constructed based on Snell’s law and non-imaging optical theory. Finally, two compensated reflectors are added at both ends of the freeform surface to reflect the unutilized light to achieve the compensation effect. By application of combined reflectors, the light pattern at the work surface 25 m away can satisfy the requirement of ECE R19 Revision 7. Also, this system has the advantages of small size and high efficiency because lens or prism groups are avoided. And the utilization of a compensated surface also increases light efficiency. Finally, a prototype model is tested, which also meets the regulatory requirements.