Patent attributes
Described are techniques and systems for determining presence of airborne particles using one or more sensors on a user device. The airborne particles include, but are not limited to, smoke resulting from combustion, dust, fog, and so forth. In one implementation, an optical proximity sensor may be used to determine a distance to an object such as a ceiling. Smoke which collects on the ceiling reflects light that is detected by the proximity sensor and results in an apparent reduction in height. A notification of this change in height may be generated. In other implementations, other techniques may be used to detect airborne particles, such as images from a camera, dedicated particular sensors, and so forth. Information about airborne particles may aid user safety. For example, an alarm may be issued indicating a potential fire or unsafe level of pollution.