荧光粉预沉淀对COB白光LED光色参数的影响

Effect of Precipitation of Phosphor on COB LED Light Color Parameters

制作了高光效高显指COB封装LED光源,研究了点涂荧光胶后光通量、色坐标、光谱等光色参数随荧光粉预沉淀时间的变化关系。研究结果表明,在预沉淀初期(约5min),LED光源光色参数随预沉淀时间变化较大,之后进入一个缓慢变化的阶段。研究认为这一现象的出现是因为粒径不同的荧光粉颗粒沉淀速度不同造成的,预沉淀初期,大粒径的荧光粉颗粒迅速沉淀,造成LED光源光色参数剧烈变化,之后小粒径的荧光粉缓慢沉淀,LED光源光色参数也呈现缓慢变化的趋势。在实际生产中,将预沉淀时间控制在15～25min,取得了良好的效果,主货率(颜色在一个档位的比例)达到98%以上。

High photosynthetic efficiency and high CRI COB LED light source was fabricated, and the influence of the change of precipitation time on the parameters such as luminous flux, color coordinate and spectra was studied. The results show that the color parameters of LED light source present a great change with the precipitation time at the initial stage(about 5min), and then enter a slowly changing phase, which is due to the different precipitation speed of the phosphors with different particle size. In early precipitation stage, large-size particles precipitate rapidly, resulting in a dramatic change of LED light color parameters, then the small-size particles of the phosphor precipitate slowly, and LED light color parameters also show a slow change trend. In the actual production, it is proposed that the precipitation time should be controlled in 15~25min so as to achieve a good effect, and the main cargo rate(the proportion of color in a stall)reaches above 98%.