We report our latest developments on a novel miniature particulate matter (PM) sensor for personal air quality monitoring. This optical sensor combines a visible fibered light source and a vertical air channel drilled out of a holed retina. The fabrication of such retina features an unconventional design of a CMOS image sensor and a specific drilling post process at wafer level. The scattering of light by a single particle generates a distinctive pattern. By using a compact optical set-up, we measure a lens-free projection of the scattering signature on the image sensor. We present the design and fabrication of such sensor as well as experimental signatures that are consistent with our in-house analytical model. We demonstrate counting and differentiation between calibrated particles of different sizes. Our current setup allows for the detection of single 320 nm polystyrene particles. Finally, we describe our image analysis procedure that fits a measured signature with a modelled one in order to retrieve particle's size and refractive index.

我们报告了用于个人空气质量监测的新型微型颗粒物（PM）传感器的最新进展。该光学传感器结合了可见的光纤光源和从有孔视网膜上钻出的垂直空气通道。这种视网膜的制造具有CMOS图像传感器的非常规设计和晶圆级的特定钻孔后处理功能。单个粒子对光的散射产生独特的图案。通过使用紧凑的光学装置，我们可以测量散射签名在图像传感器上的无透镜投影。我们介绍了这种传感器的设计和制造以及与我们内部分析模型一致的实验特征。我们展示了不同尺寸的校准颗粒之间的计数和区分。我们当前的设置允许检测单个320 nm聚苯乙烯颗粒。最后，我们描述了一种图像分析程序，该程序将测量的特征与模型特征进行拟合，以便检索粒子的尺寸和折射率。