一种环形屏积分球光源的辐照均匀度研究

Research on radiation uniformity of annular baffle integrating sphere light source

均匀光源被广泛应用于光学成像、遥感仪器的研制与标定等领域。提出了一种具有环形遮挡屏的积分球光源结构,以辐照均匀度分布特性为目标,利用蒙特卡洛(MCM)分析通过改变光源类型、挡板位置、开口大小、光源数量等参数对光源结构进行分析与优化。结果显示,朗伯特光源较之准直型光源辐照均匀度平均提高2.32%;挡板位置靠近积分球边缘时,辐照均匀度略低于其他位置;综合考虑辐射能量与照度均匀度,积分球开口比定在30%~35%区间内更为合适;辐射能量与光源数量呈线性关系,且不均匀度随光源数量在2.46%~3.38%波动。优化后的环形遮挡屏结构,可作为辐照均匀的光源应用于实际场景。

The uniform light sources are widely used in optic imaging fields ,as well as the development and calibration of remote sensing instruments. For irradiation uniformity, an integrating sphere structure with an annular baffle was proposed. Based on Monte Carlo method, the structure was analyzed and optimized by changing the parameters including light source type, baffle position, slotting size and number of light sources. Results show that the average irradiation uniformity of the Lambert light source is 2.32% higher than the collimated light source. When the baffle is located close to the edge of integrating sphere, the irradiation uniformity is slightly lower than other positions. Considering the radiation energy and illumination uniformity, the open ratio is suggested to be limited in the range of 30%~35%. The radiation power has a linear relationship with the number of light sources, and the nonuniformity fluctuates with the number of light sources from 2.46% to 3.38%. The optimized annular baffle structure is proposed as irradiated uniform light source in practical application scenario.