Light distribution design of LED lamps in classroom based on compound parabolic collector

A compound parabolic collector light distribution system was established for light distribution of LED lamps in the classroom．First the characteristics of the LED light source were analyzed, as well as the necessity of the secondary light distribution for the LED light source. The 3D nonimaging optics compound parabolic collector (CPC) model was established. The relationship between its parameters and the maximum exit half angle m was calculated by the edge light principle and the restricting factors of m were given．Then the values of all parameters of CPC model were determined according to the reading lamp illumination uniformity requirements, the CPC model was built in the optical analysis software Tracepro.The LED light source was placed on the focal plane of CPC model and the LED classroom lighting illumination distribution based on CPC was simulated combining with classroom desktop and the lamp distance．Results showed that the light uniformity cound reach more than 0.7 and satisfy the building lighting design standard GB 50034-2004 for reading lighting requirements as m was greater than 30, the effective optical flux was more than 95%.