Tiny particulate sensor technology
Conventional optical consumer PM sensors rely on a built-in fan to draw air through a cell, where the particulate count is registered and the concentration per unit of volume is calculated. The problem with this approach is the sheer physical size of such a sensor, typically around the size of a matchbox, making it impractical for use in a flat portable device, like a smartphone.
The unique PM sensor technology recently developed by Bosch Sensortec only needs natural ambient air flow to function. It is based on a camera-like principle, where three Class 1 eye-safe lasers are integrated behind a glass cover, in a similar way to the cameras in a smartphone.
This novel approach enables Bosch Sensortec to develop a PM sensing solution with dramatically smaller physical dimensions, taking up approximately one five-hundredth (0.2 %) of the volume of other solutions on the market. This reduction to the size of a match head makes this new technology ideal for personal PM2.5 measurement in consumer devices. It has low power consumption, is maintenance-free and can be integrated into a waterproof application.