Apple has made the Apple Watch a health-centric device. Now a newly granted patent, Apple describes adding a health related system designed for future smartglasses and HMD. The nasal breathing monitoring system will include an ultrasonic transducer (e.g., a microphone) to be placed on or near the outside of the user's nose and record an audio signal of the sound of the user's breathing. The application relating to monitoring system can reside on an iPhone, iPad and/or Mac.

Apple's granted patent covers systems, methods, and computer readable media for deriving nasal breathing cycles, e.g., for users of wearable devices, such as virtual reality (VR), augmented reality (AR), or extended reality (XR) systems, which may be capable of placing an ultrasonic transducer (e.g., an ultrasonic microphone) in proximity to (e.g., directly on or near) a wearer's nasal cavity. In some embodiments, spectrographs may be made and analyzed for ultrasonic breathing audio signals captured from ultrasonic transducers worn in proximity to the nose of a user of such systems.

By identifying and analyzing one or more characteristics of such audio signals, one or more parameters of such systems related to recording nasal breathing may be adjusted and/or appropriate feedback may be delivered to a user of such systems. In particular, the embodiments disclosed herein may allow for low latency (e.g., near real-time) user breathing monitoring and feedback.

In some embodiments, the spectrograph for an obtained breathing audio signal may be filtered. In some such embodiments, at least one of: a frequency range of the filter or a pole of the filter may be adjusted. In further embodiments, the spectrograph for the audio signal may have a frequency range that satisfies a first threshold frequency range criterion, and frequency spurs having a frequency range that does not satisfy a second threshold frequency range criterion may be filtered out.

In other embodiments, the gain of an amplifier may be adjusted during the processing of the audio signal, e.g., in order to compensate for a change in position of a nose-piece having an ultrasonic microphone with respect to the nose of the user of the system, to improve a signal-to-noise ratio (SNR) for the recorded breathing audio signal, etc.

In still other embodiments, an identity of the particular user currently using such a system may be determined, based on one or more characteristics of the nasal breathing.

In yet other embodiments, the system may further comprise a user interface, via which the system may provide a response, alert, or other form of feedback to the particular user currently using the system based, at least in part on an identified one or more characteristics of the particular user's nasal breathing.

In some such embodiments, the user interface may present a breathing exercise to be performed by the user, and then provide feedback to the user, based on analyzed characteristics of the particular user's nasal breathing during the breathing exercise.

In some cases, the feedback provided to a particular user may be based, at least in part, on historical data indicative of characteristics of nasal breathing during the same type of breathing exercise for one or more other users, e.g., other users that satisfy a similarity criterion with the particular system user.

Apple's patent FIG. 1 below is an example of an ultrasonic transducer, i.e., ultrasonic microphone #130, affixed to a nose-piece #120 of an exemplary wearable device #100 (e.g., smartglasses or other HMD).  The ultrasonic microphone may comprise a transducer capable of recording audio signals in the frequency range of 20 kHz or higher (e.g., up to 300 kHz).

According to the various filtering techniques, the audio signals obtained from ultrasonic microphones may be made fairly immune to vibrations and user speech patterns (e.g., modifying signal gain and/or by focusing analysis on signals in the aforementioned range of 20 kHz to 300 kHz).

Apple's patent FIG. 3 above shows an example of network-connected electronic devices for identifying characteristics of nasal breathing; FIG. 5 shows exemplary spectral signatures for an inhale phase (#500) and an exhale phase (#550) of a nasal breathing signal.

For full details, review Apple's U.S. granted patent 12160213.