Design of LED optical system based on the substrate with freeform surface

A novel method for light distribution based on the substrate with freeform surface is proposed. The freeform surface substrate is designed and stimulated by using the TracePro software. The stimulation results show that a large luminous intensity angle can be achieved by adjusting the LED chips directly onto the substrate with freeform surface. The half-intensity angle is 60, 25 bigger than using the tradition reflection cup. Furthermore, a lighting with high light efficiency and uniform illumination can be achieved by using this method. When a same average horizontal illuminance is created, it costs 25% less luminous flux and avoids 60% less luminous decay than using the traditional method. By adjusting the shape of the freeform surface to distribute the LEDs' light, not only the other patterns of luminous effects are conveniently get, but also a high quality of LED lighting can be achieved.