IN-CANAL HEART RATE MONITORING APPARATUS

• US 20180177416A1
• Filed: 02/20/2018
• Published: 06/28/2018
• Est. Priority Date: 04/29/2016
• Status: Active Grant

• Current Assignee: Fitbit, Inc. (Alphabet Inc.)
• Original Assignee: Fitbit, Inc. (Alphabet Inc.)
• Inventors: CHURCH, Andrew R., WASSON, Jaclyn Leverett, FRESCHL, Daniel Joel, VIGIL-RUIZ, Esther
• Granted Patent: US 10,842,394 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 5/02433 for infrared radiation
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: A61B 5/6814 Head
• CPC Class Codes: A61B 5/6815 Ear
• CPC Class Codes: A61B 5/7207 of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7221 Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence

Abstract

A wearable computing device includes one or more processors, memory and a physiological metric sensor system, including a light source configured to direct light into tissue of a user wearing the wearable computing device, a light detector implemented a distance away from the light source and configured to detect light from the light source that reflects back from the user, and a light-blocking portion implemented between the light source and the light detector. The wearable computing device may further include an audio port directed towards an ear canal of the user and control circuitry configured to activate the light source during a period of time and generate a light detector signal indicating an amount of light detected by the light detector during the period of time.

Claims

1. A wearable computing device comprising:

one or more processors;

memory;

a physiological metric sensor system, including;

a light source configured to direct light into tissue of a user wearing the wearable computing device;

a light detector implemented a distance away from the light source and configured to detect light from the light source that reflects back from the user; and

a light-blocking portion implemented between the light source and the light detector;

an audio port directed towards an ear canal of the user; and

control circuitry configured to;

activate the light source during a period of time; and

generate a light detector signal indicating an amount of light detected by the light detector during the period of time.

2. The wearable computing device of claim 1 further comprising one or more light field management features configured to steer or direct light from the light source to the light detector.

3. The wearable computing device of claim 2 wherein the one or more light field management features include at least one of a prism, light pipe, total internal reflection mirror, metallized mirror and a diffractive optical element.

4. The wearable computing device of claim 1 wherein the physiological metric sensor system is physically coupled to the audio port.

5. The wearable computing device of claim 1 wherein the physiological metric sensor system includes a photoplethysmographic (PPG) sensor, the PPG sensor including the light source and the light detector.

6. The wearable computing device of claim 1 wherein the light source is a light-emitting diode (LED) and the light detector is a photodiode.

7. The wearable computing device of claim 1 wherein the light source and the light detector are implemented on an outer surface of the audio port, the outer surface substantially perpendicular to a direction in which sound from the audio port is projected.

8. The wearable computing device of claim 1 wherein the light source and the light detector are implemented on an outer surface of the audio port, to provide that a configuration of the audio port in the ear canal of the user to optimize sound quality corresponds to a configuration of the light source and light detector to optimize light field management.

9. The wearable computing device of claim 1 further comprising an audio tip coupled to the audio port, the audio tip comprising an optically transparent portion and comprising the light-blocking portion implemented between the light source and the light detector.

10. The wearable computing device of claim 9 wherein the audio tip has a first size of a set of sizes.

11. The wearable computing device of claim 9 wherein the light-blocking portion is opaque.

12. The wearable computing device of claim 9 wherein the audio tip is made of silicone gel.

13. The wearable computing device of claim 9 wherein the light-blocking portion includes a light-blocking rib extending in a radial direction from the axis of the audio port to the optically transparent portion of the audio tip.

14. The wearable computing device of claim 9 wherein the light-blocking portion has a light source window to facilitate emission of light and a light detector window to facilitate detection of light.

15. The wearable computing device of claim 1 wherein the distance away from the light source corresponds to an angle between the light source and the light detector such that the amount of light travels a threshold distance in the tissue of the user and the amount of light meets a threshold percentage of light generated by the light source.

16. The wearable computing device of claim 1 wherein the audio port is communicatively coupled to an audio source.

17. The wearable computing device of claim 1 wherein the control circuitry is further configured to determine a physiological metric value based on the light detector signal.

18. (canceled)

19. (canceled)

20. A method of providing a wearable computing device, the method comprising:

providing an outer housing of the wearable computing device;

implementing an audio port by coupling it to the outer housing of the wearable computing device;

implementing a light source configured to direct light into tissue of a user wearing the wearable computing device, on an outer surface of the audio port;

implementing a light detector on the outer surface of the audio port a distance away from the light source, the light detector configured to detect light from the light source that reflects back from the user; and

implementing a light-blocking portion between the light source and the light detector.

21. The method of claim 20 further comprising implementing one or more light field management features proximal to one or both of the light source and the light detector.

22. (canceled)

23. (canceled)

24. (canceled)

25. (canceled)

26. (canceled)

27. (canceled)

28. A system for determining values of physiological metrics, comprising:

a physiological metric sensor system of a wearable computing device, including;

a light source configured to direct light into tissue of a user wearing the wearable computing device;

a light detector implemented a distance away from the light source and configured to detect light from the light source that reflects back from the user; and

a light-blocking portion implemented between the light source and the light detector; and

a client computing device communicatively coupled to the wearable computing device and configured to receive data related to detected light readings at the light detector.

29. (canceled)

30. (canceled)

31. (canceled)

32. (canceled)

33. (canceled)