Conceptual design of dedicated road lighting for city park and housing estate.

We propose dedicated road lighting, which is significantly superior to the existing lighting technologies for the city park and housing estate. This dedicated lighting employs freeform surfaces to effectively control the optical field of the LED source to produce three kinds of illumination modes for the curved road, straight road, and the small public square, respectively, perfectly matching the road conditions of the city park and housing estate. A mathematical model of freeform illumination design is presented to achieve a conceptual design of this road lighting, and a numerical technology for solving this design problem is introduced for the first time, to our knowledge. An illumination model of this conceptual design is constructed. The experimental results of the conceptual design tally closely with the target. This dedicated road lighting, integrated with energy saving, healthy lighting and artistic beauty, provides a beautiful landscape for the city park and the housing estate at night, and will play an important role in improving quality of life of the urban inhabitants.