Future Apple Watches, iPhones could detect pollen levels, air quality, even poison gas in the air as evidenced by a newly granted Apple patent (number 10,788,308) for “particulate matter sensors for portable devices.
The device would do this by using a last that could detect particles in the wind flow that reflect and/or scatter laser light. Based on the determined speed and the number of detected particles over time, the particulate matter concentration in the wind flow can be estimated.
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Here’s the summary of the patent: “Aspects of the subject technology relate to particulate matter sensors for electronic devices. A particulate matter sensor may include three lasers, three total-internal-reflection lenses, and three detectors for detecting changes in the operation of the three lasers due to the principles of self-mixing interferometry. The three total-internal-reflection lenses may use internally reflective surfaces to tilt the three beams into three corresponding directions that form an orthogonal basis in the three dimensional space, so that a gas flow speed can be determined while maintaining a small, modular form factor for implementation of the sensor in portable electronic devices.”