Indoor air pollution dominates respiration exposure because people spend most of their time indoors. Generally, indoor PM_2.5 concentrations are monitored at a fixed height in the breathing zone. However, the concentrations of PM_2.5 likely vary vertically; thus, the vertical concentration profiles would help improve the understanding of indoor air pollution. Based on the basic principle of bistatic Lidar for boundary aerosol profiling, an indoor Lidar (I-Lidar) was developed to profile the vertical distribution of PM_2.5 by imaging the PM_2.5 scattering of a vertical laser beam onto a complementary metal oxide semiconductor (CMOS) camera. Unlike bistatic Lidar, the I-Lidar views the vertical laser beam perpendicularly from the side, which enables a high and relatively uniform vertical resolution throughout the profile. The images collected by I-Lidar were adjusted for transmission and scattering attenuation and calibrated against the measured PM_2.5 concentrations using an array of PM_2.5 sensors. The new device was tested in the field, and the measurements in a living room and kitchen of a rural household revealed the existence of vertical trends and dynamic change of PM_2.5 concentrations. Potential applications of the device are discussed.

中文翻译：

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使用新型侧向散射室内激光雷达进行室内PM _2.5分析

室内空气污染占呼吸暴露的大部分，因为人们将大部分时间都花在室内。通常，室内PM _2.5浓度是在呼吸区域中的固定高度进行监测的。但是，PM _2.5的浓度可能垂直变化。因此，垂直浓度分布将有助于增进对室内空气污染的了解。基于双基地雷达的对边界气溶胶分析的基本原理，室内激光雷达（I-激光雷达）的开发是为了轮廓PM的垂直分布_2.5通过成像PM _2.5将垂直激光束散射到互补金属氧化物半导体（CMOS）相机上。与双基地激光雷达不同，I-激光雷达从侧面垂直观察垂直激光束，从而在整个轮廓上实现了较高且相对均匀的垂直分辨率。调整I-Lidar收集的图像的透射和散射衰减，并使用一系列PM _2.5传感器针对测得的PM _2.5浓度进行校准。新设备已在现场进行了测试，在农村家庭的起居室和厨房中进行的测量表明存在垂直趋势和PM _2.5浓度的动态变化。讨论了该设备的潜在应用。