We put forward a non-contact method for determining the transient two-dimensional (2D) temperature distribution of light emitting diodes (LEDs). A high-speed camera is employed to acquire the 2D reflective light of blue LED under test (468 nm) illuminated by a red LED (690 nm) as the incident light source to avoid the band-gap modulation effect. The 2D transient temperature distribution is derived in terms of temperature-dependent reflective light intensity relationship. Two cases are studied to test the system in this work under (1) 1980 fps frame rate with time resolution of 505 μs at 300 mA, and (2) 5600 fps with time resolution of 179 μs at 500 mA. Compared with the conventional infrared thermal imaging (TI) method, the spatial resolution and the time resolution of this proposed method increase up to one and two orders of magnitude, respectively.

中文翻译：

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使用高速相机测量 GaN 发光二极管的二维瞬态温度分布


我们提出了一种非接触式方法来确定发光二极管 (LED) 的瞬态二维 (2D) 温度分布。采用高速相机采集红色LED（690 nm）作为入射光源照射被测蓝色LED（468 nm）的二维反射光，以避免带隙调制效应。二维瞬态温度分布是根据温度相关的反射光强度关系得出的。研究了两种情况来测试本工作中的系统：(1) 1980 fps 帧速率，300 mA 下时间分辨率为 505 μs，以及 (2) 5600 fps，500 mA 下时间分辨率为 179 μs。与传统的红外热成像（TI）方法相比，该方法的空间分辨率和时间分辨率分别提高了一个和两个数量级。