图案化基板LED中荧光粉对光学性能的影响

采用基板上加倒锥形图案化的新型封装方式,用蒙特卡洛光线追迹法仿真保形涂覆荧光粉体积比和厚度变化时,发光二极管(LED)光源光色品质的变化.仿真结果表明:LED光源的出光效率在图案化倾斜角α为30°,45°时,出光效率的提升量最大;α为45°时,传统平面封装光源的空间颜色均匀性最大优化幅度分别为9.1%,8.4%;荧光粉厚度、体积比不变时,颜色均匀性相对于传统平面封装光源的优化幅度最大为11.1%,10.4%,光源的色温差值最大减小1 006,1 319 K;在厚度、体积比参数中任选一个进行优化,均可改善LED产品的颜色均匀性,而优化图案化结构可使空间颜色均匀性更明显地提高.

Influence of Phosphor Coating Layer to Optical Performance ofLED With Patterned Board

Effects of variations of conformal coating phosphors thickness and volume ratio on optical consistency of the new packaging light emitting diodes(LED)including the luminous and chromatic performance were simulated studied by Monte Carlo ray tracing method. The new packaging LED had a patterned board with regular invert cone structures. Simulation results revealed that a maximum light extraction efficiency improvement of the LED would achieve when the inclination angles of the invert cone structures were 30° and 45°. When α=45°, the largest improvement of angular color uniformity(ACU)compared to traditional planar packaging was 9.1% and 8.4% respectively. When the phosphor volume ratio and thickness were not changed, the largest improvement of ACU was 11.1% and 10.4%. When the thickness and the volume ratio of the phosphor layer changed, the correlated color temperature difference value of patterned structure LED was 1 006, 1 319 K lower than the LED with planar board. At this point, the patterned board has an obvious impact on the ACU of the LED. Optimization of phosphor layer thickness or volume ratio parameters can improve the light quality of LED packages. In the meantime, optimize the patterned structure can make the space color uniformity increase more obviously.