荧光粉沉淀是影响白光LED发光质量和光学一致性的关键因素。为了实现荧光粉沉淀的快速、无损检测，提出一种基于光学相干层析（OCT）技术的荧光粉沉淀检测方法。使用OCT系统对白光LED进行成像，比较白光LED的OCT与切片图像，分析了荧光粉的数量分布和沉淀物形态。根据荧光粉数量与面积分数的关系以及荧光粉沉淀过程中荧光粉数量分布的变化特点，设计了从OCT图像中提取荧光粉面积分数的算法，分析了荧光粉面积分数与荧光粉沉淀程度的变化关系。实验结果表明，OCT技术可以准确检测白光LED的荧光粉沉淀物形态，荧光粉在OCT图像中的面积分数可以量化荧光粉沉淀程度。该方法可以满足白光LED荧光粉沉淀的检测要求，并可用于白光LED的质量检测和封装工艺研究。

Phosphor sedimentation is a key factor affecting the light quality and optical consistency of white light-emitting diodes (LEDs). Herein, a detection method based on optical coherence tomography (OCT) is proposed to realize rapid, nondestructive detection of phosphor sedimentation in white LEDs. For this purpose, a white LED was imaged by an OCT system. Subsequently, the OCT and section images of the LED were compared, and the quantity distribution and sediment morphology of phosphor were analyzed. In addition, an algorithm was developed to extract the area fraction of phosphor from the OCT images based on the relationship between the quantity and area fraction of phosphor and the variations in quantity distribution during sedimentation. Furthermore, the relationship between the area fraction of phosphor and the degree of phosphor sedimentation was studied. The experimental results show that OCT can accurately determine the phosphor sediment morphology in white LEDs and that the area fraction of phosphor observed in the OCT images can quantify the degree of phosphor sedimentation. This method can meet the detection requirements of phosphor sedimentation in white LEDs and can be used for their quality testing and packaging process research.