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电子工程专辑
4 年
中国EMC LED封装厂商综合竞争力排名一览
LED白光封装市场技术不断在演进,材料也在不断的发生变化。以支架材料为例,最早期主要以PPA材料为主,然而随着中大功率LED器件产品的需求量增加,PPA材料的支架已经不适用。PPA在高温下长时间使用后会产生黄化及老化现象,另外白光是由蓝光芯片激发荧光 ...
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