公开(公告)号：US20200096310A1

公开(公告)日：2020-03-26

申请号：US16518888

申请日：2019-07-22

Applicant: Apple Inc.

Inventor： Mehmet MUTLU ,  James j. DUDLEY ,  Mark T. WINKLER ,  Wenrui CAI

IPC: G01B9/02

Abstract: 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.