Optical sensor for a wearable device

• US 10,307,101 B1
• Filed: 12/30/2015
• Issued: 06/04/2019
• Est. Priority Date: 02/17/2015
• Status: Active Grant

• Current Assignee: HALO Wearables LLC
• Original Assignee: HALO Wearables LLC
• Inventors: Miller, David R., Lee, Jeffrey M., Miller, Devin W.
• Primary Examiner(s): Winakur, Eric F
• Assistant Examiner(s): Janoschka, Darin M
• Application Number:
  US14/985,249
• Time in Patent Office: 1,252 Days
• Field of Search: 600300-399
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 2560/0209 adapted for power saving
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 2560/0257 using atmospheric pressure
• CPC Class Codes: A61B 2560/0456 Apparatus provided with a docking unit
• CPC Class Codes: A61B 2560/0475 Special features of memory means, e.g. removable memory cards
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 2562/0223 Magnetic field sensors
• CPC Class Codes: A61B 2562/0261 Strain gauges
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/4875 Hydration status, fluid retention of the body
• CPC Class Codes: A61B 5/6801 specially adapted to be attached to or worn on the body surface
• CPC Class Codes: A61B 5/6803 Head-worn items, e.g. helmets, masks, headphones or goggles
• CPC Class Codes: A61B 5/681 : Wristwatch-type devices
• CPC Class Codes: A61B 5/7221 : Determining signal validity, reliability or quality A61B5/7207 and A61B5/7217 take precedence
• CPC Class Codes: A61B 5/7278 : Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• CPC Class Codes: A61B 5/742 : using visual displays A61B5/339 takes precedence
• CPC Class Codes: H04W 52/0254 : detecting a user operation or a tactile contact or a motion of the device
• CPC Class Codes: H04W 52/0261 : managing power supply demand, e.g. depending on battery level
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

A method, system, or apparatus for determining a hydration condition of a user. The apparatus includes a housing. The apparatus further includes a light source disposed at an edge of the housing in a first position, wherein the light source, when affixed to a surface of a body, is operable to emit light into the body from the first position. The apparatus further includes an optical sensor disposed at the edge of the housing in a second position, the second position being a fixed distance from the first position to measure backscatter of the light reflected by a muscular-walled tube of the body at a depth below the surface of the body.

Claims

1. An electronic device comprising:

a housing having an outer surface shaped to affix to a body of a user, wherein the housing comprises a first cavity, a second cavity, and a third cavity;

a first light source embedded within the first cavity at a first position;

wherein

the first light source is operable to emit a first light into the body at a first wavelength of light corresponding to a wavelength absorbed by sodium, and

a second light source embedded within the second cavity at a second position;

wherein;

the second light source is operable to emit a second light into the body at a second wavelength of light corresponding to a wavelength absorbed by potassium;

an optical sensor embedded within the third cavity at a third position, wherein

the optical sensor is to detect a portion of the first light and the second light reflected by a muscular-walled tube of the body at a depth below an exterior of the body of the user; and

a processing device is to;

determine a sodium to potassium ratio of the user based on the reflected first light and the reflected second light; and

determine a hydration condition of the user based a trend of the sodium to potassium ratio over a period of time.

2. The electrical device of claim 1, further comprising:

a sensor interface, coupled to the optical sensor, wherein the sensor interface is to;

receive, from the optical sensor, the portion of first light and the second light reflected from the muscular-walled tube;

take a first measurement of backscatter of the first wavelength of light using the detected portion of the first light; and

take a second measurement of backscatter of the second wavelength of light using the detected portion of the second light.

3. The electrical device of claim 2, further wherein the processing device is further to:

compare the first measurement of backscatter of the first wavelength of light to a previous measurement of backscatter of the first wavelength of light;

determine a change in a sodium level of the body when an amount of backscatter of the first wavelength of light changes;

compare the second measurement of backscatter of the second wavelength of light to a previous measurement of backscatter of the second wavelength of light; and

determine a change in a potassium level of the user when an amount of backscatter of the second wavelength of light changes.

4. The electrical device of claim 3, wherein the processing device is further to determine that the hydration condition of the user is in a dehydrated condition when the sodium level decreases.

5. The electrical device of claim 3, wherein the processing device is further to determine that the hydration condition of the user is in a dehydrated when the potassium level exceeds the sodium level.

6. The electrical device of claim 1, wherein the first wavelength of light is between 535 nanometers and 735 nanometers and wherein the second wavelength of light is between 680 nanometers and 880 nanometers.

7. An apparatus comprising:

a housing;

a light source disposed at an edge of the housing in a first position, wherein the light source, when affixed to a surface of a body, is operable to emit light into the body from the first position;

a first optical sensor disposed at the edge of the housing in a second position, the second position being a first fixed distance from the first position to measure a first backscatter of the light from an artery of the body at a first depth below the surface of the body; and

a second optical sensor disposed at the edge of the housing in a third position, the third position being a second fixed distance from the first position to measure a second backscatter of the light from a vein of the body at a second depth below the surface of the body

a processing device configured to determine a trend in a hydration condition of the body based on the first backscatter of light and the second backscatter of light.

8. The apparatus of claim 7, wherein the housing comprising a cavity disposed on a first plane of an outer surface of the housing, wherein the light source is embedded within the cavity such that a first end of the light source does not extend beyond the first plane of the outer surface of the housing.

9. The apparatus of claim 8, wherein the light source is embedded within the cavity such that the first end of the light source is flush with the first plane.

10. The apparatus of claim 9 wherein the light source emits light of a first wavelength between 535 nanometers and 735 nanometers and a second wavelength between 680 nanometers and 880 nanometers.

11. The apparatus of claim 10, wherein the first wavelength corresponds to a measurement of sodium in the body between 535 nanometers (nm) and 735 nm.

12. The apparatus of claim 10, wherein the second wavelength corresponds to a measurement of potassium in the body between 680 nanometers (nm) and 880 nm.

13. The apparatus of claim 7, wherein the processing device is further configured to:

determine a sodium to potassium ratio of the body based on the first backscatter of light and the second backscatter of light; and

determine the hydration condition of the body based on a trend of the sodium to potassium ratio.

14. A method comprising:

emitting, by a light source affixed to a body at a first position, a first wavelength of light into the body;

receiving, by an optical sensor affixed to the body at a second position, light from a depth below a of the body corresponding to a muscular-walled tube of the body, wherein;

the first position is at a fixed distance from the second position to detect backscatter from the depth below the surface of the body; and

the first position of the light source is at a first side of the muscular walled tube of the body and the second position of the optical sensor is at a second side of the muscular walled tube such that the light source and the optical sensor straddle the muscular walled tube;

determining, by a sensor interface, a current sodium to potassium ratio of the body based on the detected backscatter of the first wavelength of light;

comparing, by a processing device, the current sodium to potassium ratio to a previous sodium to potassium ratio of the body; and

determining a hydration condition of the body when the current sodium to potassium ratio is different than the previous sodium to potassium ratio.

15. The method of claim 14, further comprising:

determining the hydration condition of the body is a dehydration condition when the detected backscatter decreases;

determining the hydration condition of the body is a hydrated condition when the detected backscatter increases; and

determining the hydration condition of the body is a stable when the detected backscatter is unchanged.

16. The method of claim 14, wherein the first wavelength of light is between 535 nanometers and 735 nanometers and corresponds to a measurement of sodium in the body.

17. The method of claim 14, wherein the first wavelength of light is between 680 nanometers and 880 nanometers and corresponds to a measurement of potassium in the body.

18. The method of claim 14, wherein the first wavelength of light is between 400 nanometers (nm) and 1800 nm.

19. The method of claim 14, further comprising determining the hydration condition based on a trend of the sodium to potassium ratio over time.

20. The method of claim 14, further comprising determining a trend in the hydration condition of the body based on the trend of the sodium to potassium ratio.