像素分割对LED电流密度及光照度分布的影响

Current Density and Irradiance Distribution of Light-emitting-diode-array Device with Divided Pixels

将300μm×300μm LED芯片阵列化为间隔为20μm的3×3个80μm×80μm的子单元,阵列化后,总饱和光输出功率是未阵列化前的5.19倍,最大注入电流提高近7倍,表明阵列可以注入更大的电流和输出更高的饱和光功率。此外,采用多颗阵列化后的LED芯片形成的芯片组照明,得知芯片组间距为最大平坦条件dmax时,接收面上照度均匀性最佳;芯片组数越多,接收面上均匀照度的面积越大。同时,9颗300μm×300μm的芯片阵列化为9个80μm×80μm LED芯片后,以dmax排列照明相对于9颗未阵列化的300μm×300μm芯片以dmax排列照明时,接收面上的光照度均匀性不变,照度值提高了3倍。

When a 300 μm × 300 μm chip is divided into 3 × 3 small chips with 20 μm adjacent spacing,the total saturated output power enhances up to 5. 19 times and the maximum inject current increases 7 times nearly. The consequences indicate LED chip with smaller pixels array can possess greater inject current and higher saturated output power than the primary chip. Meanwhile,the effects of chips number and LED chips distance for irradiance distribution on target plane illuminated by multi-LED chips are studied. The irradiance uniformity reaches its peaks when LED chip-to-chip distance equals to maximum flat condition dmax. In addition,the irradiance uniformity area is increasing when the number of LED chips increasing. When the target plane is illumined by nine 300μm × 300 μm LED chips with distance dmaxand each chip is divided into nine 80 μm × 80 μm smaller pixels,the irradiance value is 3 times as primary LED chips array while the uniformity of irradiance not changing.