Physiological measurement device using light emitting diodes

• US 10,213,113 B2
• Filed: 06/24/2018
• Issued: 02/26/2019
• Est. Priority Date: 12/31/2012
• Status: Expired due to Fees

• Current Assignee: Omni Medsci, Inc.
• Original Assignee: Omni Medsci, Inc.
• Inventors: Islam, Mohammed N.
• Primary Examiner(s): Rahman, Md M
• Application Number:
  US16/016,649
• Publication Number:
  US 20180296098A1
• Time in Patent Office: 247 Days
• Field of Search: 356300
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 2562/0238 Optical sensor arrangements for performing transmission measurements on body tissue
• CPC Class Codes: A61B 2562/146 for optical coupling
• CPC Class Codes: A61B 2576/02 specially adapted for a particular organ or body part
• CPC Class Codes: A61B 5/0013 Medical image data A61B1/00011, A61B6/56, A61B8/56 take precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0024 for multiple sensor units attached to the patient, e.g. using a body or personal area network
• 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 5/0086 using infrared radiation
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• 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 5/4547 Evaluating teeth
• CPC Class Codes: A61B 5/6801 specially adapted to be attached to or worn on the body surface
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/7405 using sound
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61C 1/0046 Dental lasers surgical lasers A61B18/20; working by laser beam in general B23K26/00; lasers per se H01S3/00
• CPC Class Codes: A61C 19/04 : Measuring instruments specially adapted for dentistry A61C5/44 takes precedence; testing vitality of teeth A61B5/0534; radiation diagnosis specially adapted for dentistry A61B6/51
• CPC Class Codes: G01J 2003/104 : Monochromatic plural sources
• CPC Class Codes: G01J 2003/1208 : Prism and grating
• CPC Class Codes: G01J 2003/2826 : Multispectral imaging, e.g. filter imaging
• CPC Class Codes: G01J 3/0218 : using optical fibers
• CPC Class Codes: G01J 3/108 : for measurement in the infrared range
• CPC Class Codes: G01J 3/14 : using refracting elements, e.g. prisms G01J3/18, G01J3/26 take precedence prisms per se G02B5/04
• CPC Class Codes: G01J 3/1838 : Holographic gratings
• CPC Class Codes: G01J 3/28 : Investigating the spectrum using colour filters G01J3/51
• CPC Class Codes: G01J 3/2823 : Imaging spectrometer
• CPC Class Codes: G01J 3/42 : Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 3/453 : by correlation of the amplitudes
• CPC Class Codes: G01M 3/38 : by using light G01M3/02 takes precedence
• CPC Class Codes: G01N 2021/3595 : using FTIR
• CPC Class Codes: G01N 2021/399 : Diode laser
• CPC Class Codes: G01N 21/35 : using infrared light G01N21/39 takes precedence
• CPC Class Codes: G01N 21/3563 : for analysing solids; Preparation of samples therefor
• CPC Class Codes: G01N 21/359 : using near infrared light
• CPC Class Codes: G01N 21/39 : using tunable lasers
• CPC Class Codes: G01N 21/85 : Investigating moving fluids or granular solids
• CPC Class Codes: G01N 21/88 : Investigating the presence of flaws or contamination
• CPC Class Codes: G01N 21/9508 : Capsules; Tablets
• CPC Class Codes: G01N 2201/061 : Sources
• CPC Class Codes: G01N 2201/06113 : Coherent sources; lasers
• CPC Class Codes: G01N 2201/062 : LED's
• CPC Class Codes: G01N 2201/08 : Optical fibres; light guides
• CPC Class Codes: G01N 2201/12 : Circuits of general importance; Signal processing
• CPC Class Codes: G01N 2201/129 : Using chemometrical methods
• CPC Class Codes: G01N 33/02 : Food
• CPC Class Codes: G01N 33/025 : Fruits or vegetables
• CPC Class Codes: G01N 33/15 : Medicinal preparations ; Physical properties thereof, e.g. dissolubility
• CPC Class Codes: G01N 33/442 : Resins; Plastics
• CPC Class Codes: G01N 33/49 : Blood chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80
• CPC Class Codes: G16H 40/67 : for remote operation
• CPC Class Codes: G16Z 99/00 : Subject matter not provided for in other main groups of this subclass
• CPC Class Codes: H01S 3/0092 : Nonlinear frequency conversion, e.g. second harmonic generation [SHG] or sum- or difference-frequency generation outside the laser cavity nonlinear frequency conversion per se G02F1/35
• CPC Class Codes: H01S 3/06758 : Tandem amplifiers
• CPC Class Codes: H01S 3/302 : in an optical fibre

Abstract

A wearable device includes a measurement device adapted to be placed on a wrist or ear having a light source with LEDs to measure physiological parameters. The measurement device generates an optical beam having a near infrared wavelength between 700-2500 nanometers by modulating the LEDs, and lenses to deliver the beam to tissue, which reflects the beam to a receiver having spectral filters in front of spatially separated detectors coupled to analog to digital converters that generate at least two receiver outputs. Signal-to-noise ratio of the beam reflected from the tissue is improved by comparing the receiver outputs, and by increasing light intensity from the LEDs. The receiver is synchronized to the modulation of the LEDs and uses a lock-in technique that detects the modulation frequency. The measurement device generates an output signal representing a non-invasive measurement on blood within the tissue.

Claims

1. A wearable device, comprising:

a measurement device to measure a physiological parameter adapted to be placed on a wrist or an ear of a user, comprising at least a first light emitting diode and a second light emitting diode, the first light emitting diode configured to generate a first output optical beam, the first output optical beam having an initial light intensity and at least one near-infrared wavelength between 700 nanometers and 2500 nanometers, the second light emitting diode configured to generate a second output optical beam, the second output optical beam having an initial light intensity and at least one near-infrared wavelength between 700 nanometers and 2500 nanometers;

the measurement device further comprising a receiver, the receiver having a first detector and a second detector, the first and second detectors being spatially separated, the first detector configured to receive at least a first reflected portion of the first output optical beam, the second detector configured to receive at least a first reflected portion of the second output optical beam;

one or more analog to digital converters coupled to the spatially separated detectors and configured to generate a first detector signal representing at least in part the first reflected portion of the first output optical beam and to generate a second detector signal representing at least in part the first reflected portion of the second output optical beam, and wherein the receiver is configured to generate an output signal at least in part by comparing the first detector signal and the second detector signal;

the measurement device configured to improve signal-to-noise ratio of the output signal by increasing light intensity relative to the initial light intensity of at least the first light emitting diode;

wherein the measurement of the physiological parameter is at least in part a non-invasive measurement on blood; and

wherein the measurement device is configured to modulate at least the first light emitting diode at a modulation frequency, and wherein the receiver is configured to synchronize to the modulation frequency.

2. The wearable device of claim 1 wherein one of the spatially separated detectors is located a first distance from the first light emitting diode and a different distance from the second light emitting diode such that the receiver can receive a first reflected portion of the first output optical beam and a first reflected portion of the second output optical beam, and wherein the receiver is configured to generate a detector output signal at least in part by comparing the received first reflected portion of the first output optical beam and the received first reflected portion of the second output optical beam.

3. The wearable device of claim 2, wherein the receiver is further configured to:

generate a first receiver signal from light detected while the first and second light emitting diodes are off, and

generate a second receiver signal from light detected while at least one of the first and second light emitting diodes is on including at least a portion of the first reflected portion of the first output optical beam;

and

wherein the measurement device is configured to further improve the signal-to-noise ratio of the output signal by differencing the first receiver signal and the second receiver signal.

4. The wearable device of claim 3, wherein the receiver is configured to perform filtering at the modulation frequency, and wherein the modulation frequency has a phase, and wherein the receiver is configured to lock onto the phase.

5. The wearable device of claim 4, wherein the measurement device further comprises a reflective surface positioned to receive and redirect toward the spatially separated detectors at least some of the first output optical beam as a second reflected portion of the first output optical beam, and

wherein the at least one near-infrared wavelength of the first light emitting diode is between 900 nanometers and 1150 nanometers.

6. The wearable device of claim 5, wherein the wearable device is configured to communicate with a smart phone or tablet, the smart phone or tablet comprising a wireless receiver, a wireless transmitter, a display, a voice input module, a speaker, and a touch screen, the smart phone or tablet configured to receive and to process at least a portion of the output signal, wherein the smart phone or tablet is configured to store the processed portion of the output signal and to transmit at least a portion of the stored output signal as a transmitted signal over a wireless transmission link to a remote device;

wherein the remote device is configured to receive over the wireless transmission link at least part of the transmitted signal as a received signal, to process the received signal to generate processed data, and to store the processed data, and wherein the remote device is capable of retrieving a history of at least a portion of the processed data; and

wherein the remote device is further configured to transmit at least a portion of the processed data to one or more other locations, wherein the one or more other locations is selected from the group consisting of the smart phone or tablet, a doctor, a healthcare provider, a cloud-based server and one or more designated recipients.

7. The wearable device of claim 3, wherein the measurement device further comprises a reflective surface positioned to receive and redirect toward the spatially separated detectors at least some of the first output optical beam as a second reflected portion of the first output optical beam, and

wherein the at least a portion of the near-infrared wavelengths of the first light emitting diode is between 900 nanometers and 1150 nanometers.

8. The wearable device of claim 7, wherein the receiver is configured to perform filtering at the modulation frequency, and wherein the modulation frequency has a phase, and wherein the receiver is configured to lock onto the phase.

9. The wearable device of claim 8, wherein the wearable device is configured to communicate with a smart phone or tablet, the smart phone or tablet comprising a wireless receiver, a wireless transmitter, a display, a voice input module, a speaker, and a touch screen, the smart phone or tablet configured to receive and to process at least a portion of the output signal, wherein the smart phone or tablet is configured to store the processed portion of the output signal and to transmit at least a portion of the stored output signal as a transmitted signal over a wireless transmission link to a remote device;

wherein the remote device is configured to receive over the wireless transmission link at least part of the transmitted signal as a received signal, to process the received signal to generate processed data, and to store the processed data, and wherein the remote device is capable of retrieving a history of at least a portion of the processed data, and

wherein the remote device is further configured to transmit at least a portion of the processed data to one or more other locations, wherein the one or more other locations is selected from the group consisting of the smart phone or tablet, a doctor, a healthcare provider, a cloud-based server and one or more designated recipients.

10. A wearable device, comprising:

a measurement device to measure a physiological parameter adapted to be placed on a wrist or an ear of a user comprising at least a first light emitting diode and a second light emitting diode, the first light emitting diode configured to generate a first optical beam, the first optical beam having an initial light intensity and at least one near-infrared wavelength between 700 nanometers and 2500 nanometers, the second light emitting diode configured to generate a second optical beam, the second optical beam having an initial light intensity and at least one near-infrared wavelength between 700 nanometers and 2500 nanometers;

the measurement device configured to output at least a portion of the first optical beam as a first output optical beam, and to output at least a portion of the second optical beam as a second output optical beam;

the measurement device further comprising a receiver having one or more detectors, wherein one of the one or more detectors is located a first distance from the first light emitting diode and a different distance from the second light emitting diode to be capable of receiving at least a first reflected portion of the first output optical beam and generating a first detector signal, and receiving at least a first reflected portion of the second output optical beam and generating a second detector signal;

wherein the receiver is configured to generate an output signal in part by comparing the first detector signal and the second detector signal;

the measurement device configured to improve signal-to-noise ratio of the output signal by increasing light intensity relative to the initial light intensity of at least the first light emitting diode;

wherein the measurement of the physiological parameter is at least in part a non-invasive measurement on blood; and

wherein the measurement device is configured to modulate at least the first light emitting diode at a modulation frequency, and wherein the receiver is configured to detect and to synchronize to the modulation frequency.

11. The wearable device of claim 10, wherein the one or more detectors comprises a plurality of spatially separated detectors, the receiver further comprising one or more analog to digital converters coupled to the spatially separated detectors, the one or more analog to digital converters configured to generate at least two receiver outputs, and the measurement device configured to compare the at least two receiver outputs;

and

wherein the receiver further comprises one or more spectral filters positioned in front of at least some of the spatially separated detectors.

12. The wearable device of claim 11, wherein the receiver is further configured to:

generate a first signal from light detected while the light emitting diodes are off, and

generate a second signal from light detected while at least one of the light emitting diodes is on, wherein the detected light while at least one of the light emitting diodes is on includes at least the first reflected portion of the first or second output optical beams;

and

wherein the measurement device is configured to improve the signal-to-noise ratio of the first reflected portion of the first or second output optical beams by differencing the first signal and the second signal.

13. The wearable device of claim 12, wherein the receiver is configured to perform filtering at the modulation frequency, and wherein the modulation frequency has a phase, and wherein the receiver is configured to lock onto the phase.

14. The wearable device of claim 13, wherein the measurement device further comprises a reflective surface positioned to redirect at least some of the first reflected portion of the first or second output optical beams toward the spatially separated detectors.

15. The wearable device of claim 14, wherein the wearable device is configured to communicate with a smart phone or tablet, the smart phone or tablet comprising a wireless receiver, a wireless transmitter, a display, a voice input module, a speaker, and a touch screen, the smart phone or tablet configured to receive and to process at least a portion of the output signal, wherein the smart phone or tablet is configured to store and display the processed output signal, wherein at least a portion of the processed output signal is configured to be transmitted over a wireless transmission link.

16. The wearable device of claim 15, wherein at least one of the light emitting diodes emits at a first wavelength and at least another one of the light emitting diodes emits at a second wavelength different from the first wavelength, and wherein the output signal is generated in part by comparing signals from detection of the first reflected portion of the first or second optical output beam at the first wavelength with signals from detection of the first reflected portion of the first or second optical output beam at the second wavelength.

17. The wearable device of claim 10, wherein the wearable device is configured to communicate with a smart phone or tablet, the smart phone or tablet comprising a wireless receiver, a wireless transmitter, a display, a voice input module, a speaker, and a touch screen, the smart phone or tablet configured to receive and to process at least a portion of the output signal, wherein the smart phone or tablet is configured to store and display the processed portion of the output signal, wherein at least a portion of the processed portion of the output signal is configured to be transmitted over a wireless transmission link;

and

wherein the measurement device further comprises a reflective surface positioned to receive and redirect toward the spatially separated detectors at least some of the first reflected portion of the first or second optical output beam.

18. The wearable device of claim 17, wherein at least one of the light emitting diodes emits at a first wavelength and at least another one of the light emitting diodes emits at a second wavelength different from the first wavelength, and wherein the output signal is generated in part by comparing the first reflected portion of the first or second optical output beam received by the spatially separated detectors at the first wavelength with the first reflected portion of the first or second optical output beam received by the spatially separated detectors at the second wavelength.

19. The wearable device of claim 10, wherein the wearable device is configured to communicate with a smart phone or tablet, the smart phone or tablet comprising a wireless receiver, a wireless transmitter, a display, a voice input module, a speaker, and a touch screen, the smart phone or tablet configured to receive and to process at least a portion of the output signal, wherein the smart phone or tablet is configured to store the processed output signal, wherein at least a portion of the processed output signal is configured to be transmitted over a wireless transmission link as a transmitted signal to a remote device;

and

wherein the remote device is configured to receive over the wireless transmission link at least part of the transmitted signal, to process the at least part of the transmitted signal to generate processed data and to store the processed data, and wherein the remote device is capable of retrieving a history of at least a portion of the stored processed data.

20. The wearable device of claim 19, wherein the receiver further comprises one or more spectral filters positioned in front of at least some of the spatially separated detectors.

21. The wearable device of claim 20, wherein at least one of the light emitting diodes emits at a first wavelength and at least another of the light emitting diodes emits at a second wavelength, and wherein the first wavelength has a first penetration depth and wherein the second wavelength has a second penetration depth different from the first penetration depth, and wherein the output signal is generated in part by comparing the first reflected portion of the first or second optical output beam received by the spatially separated detectors at the first wavelength with the first reflected portion of the first or second optical output beam received by the spatially separated detectors at the second wavelength.

22. A wearable device, comprising:

a measurement device to measure a physiological parameter adapted to be placed on a wrist or an ear of a user, comprising at least a first light emitting diode and a second light emitting diode, the first light emitting diode configured to generate a first optical beam, the first optical beam having an initial light intensity and at least one near-infrared wavelength between 700 nanometers and 2500 nanometers, the second light emitting diode configured to generate a second optical beam, the second optical beam having an initial light intensity and at least one near infrared wavelength between 700 nanometers and 2500 nanometers;

the measurement device configured to output at least a portion of the first optical beam as a first output optical beam, and to output at least a portion of the second optical beam as a second output optical beam;

the measurement device further comprising a receiver having a first detector and a second detector, the first and second detectors being spatially separated, the first detector configured to receive at least a first reflected portion of the first output optical beam and to generate a first detector signal in response, the second detector configured to receive at least a first reflected portion of the second output optical beam and to generate a second detector signal in response;

wherein at least one of the first and second detectors is located a first distance from the first light emitting diode and a different distance from the second light emitting diode and configured to receive at least a second reflected portion of the first output optical beam and to generate a third signal in response, and configured to receive at least a second reflected portion of the second output optical beam and to generate a fourth detector signal in response;

the measurement device configured to generate an output signal representing at least in part a non-invasive measurement on blood, the output signal generated at least in part by comparing the first detector signal with the second detector signal, and comparing the third detector signal with the fourth detector signal;

the measurement device further configured to improve the signal-to-noise ratio of the output signal by increasing light intensity relative to the initial light intensity of at least the first light emitting diode;

wherein at least one of the first light emitting diode and the second light emitting diode is modulated at a modulation frequency;

wherein the receiver is configured to be synchronized to the modulating of the at least one of the first and second light emitting diodes; and

wherein the receiver is configured to detect at the modulation frequency.

23. The wearable device of claim 22, wherein the receiver is configured to perform filtering at the modulation frequency, and wherein the modulation frequency has a phase, and wherein the receiver is configured to lock onto the phase.

24. The wearable device of claim 23, wherein the measurement device further comprises a reflective surface positioned to receive and redirect toward the spatially separated detectors at least some of the first portion of the first optical output beam, and wherein the at least one near-infrared wavelength of the first optical beam comprises a wavelength between 900 nanometers and 1150 nanometers.

25. The wearable device of claim 24, wherein the receiver is further configured to:

generate a first receiver signal responsive to light received while the first and second light emitting diodes are off, and

generate a second receiver signal responsive to light received while at least one of the first and second light emitting diodes is on, wherein the light received while at least one of the first and second light emitting diodes is on includes at least a portion of the first reflected portion of the first output optical beam or the second output optical beam;

and

wherein the measurement device is configured to further improve the signal-to-noise ratio of output signal by differencing the first receiver signal and the second receiver signal.

26. The wearable device of claim 25, wherein the receiver further comprises one or more spectral filters positioned in front of at least some of the spatially separated detectors.

27. The wearable device of claim 26, wherein the wearable device is configured to communicate with a smart phone or tablet, the smart phone or tablet comprising a wireless receiver, a wireless transmitter, a display, a voice input module, a speaker, and a touch screen, the smart phone or tablet configured to receive and to process at least a portion of the output signal, wherein the smart phone or tablet is configured to store the processed portion of the output signal, wherein at least a portion of the processed output signal is configured to be transmitted over a wireless transmission link as a transmitted signal to a remote device;

the remote device configured to receive over the wireless transmission link at least part of the transmitted signal, to process the at least part of the transmitted signal to generate processed data and to store the processed data, and wherein the remote device is capable of retrieving a history of at least a portion of the stored processed data.

28. The wearable device of claim 27, wherein at least one of the first and second light emitting diodes emits at a first wavelength and at least another of the first and second light emitting diodes emits at a second wavelength, and wherein the first wavelength has a first penetration depth and wherein the second wavelength has a second penetration depth different from the first penetration depth, and wherein the output signal is generated in part by comparing a signals responsive to light received by at least one of the spatially separated detectors at the first and second wavelengths.

29. The wearable device of claim 22, wherein the measurement device further comprises a reflective surface positioned to receive and redirect toward the spatially separated detectors at least some of the first portion of the first optical output beam, and wherein the at least one near-infrared wavelength of the first optical beam comprises a wavelength between 900 nanometers and 1150 nanometers.

30. The wearable device of claim 29, wherein the receiver is further configured to:

generate a first receiver signal responsive to light received while the first and second light emitting diodes are off, and

generate a second receiver signal responsive to light received while at least one of the first and second light emitting diodes is on, wherein the light received while at least one of the first and second light emitting diodes is on includes at least a portion of the first reflected portion of the first output optical beam or the second output optical beam;

and

wherein the measurement device is configured to further improve the signal-to-noise ratio of output signal by differencing the first receiver signal and the second receiver signal.

31. The wearable device of claim 30, wherein the receiver is configured to perform filtering at the modulation frequency, and wherein the modulation frequency has a phase, and wherein the receiver is configured to lock onto the phase.