Multi-stream data collection system for noninvasive measurement of blood constituents
The present disclosure relates to noninvasive methods, devices, and systems for measuring various blood constituents or analytes, such as glucose. In an embodiment, a light source comprises LEDs and super-luminescent LEDs. The light source emits light at at least wavelengths of about 1610 nm, about 1640 nm, and about 1665 nm. In an embodiment, the detector comprises a plurality of photodetectors arranged in a special geometry comprising one of a substantially linear substantially equal spaced geometry, a substantially linear substantially non-equal spaced geometry, and a substantially grid geometry.
1. A user-worn physiological measurement device that defines a plurality of optical paths, the physiological measurement device comprising:
one or more emitters configured to emit light into tissue of a user;
a first set of photodiodes positioned on a first surface and surrounded by a wall that is operably connected to the first surface, wherein:
the first set of photodiodes comprises at least four photodiodes, and
the photodiodes of the first set of photodiodes are connected to one another in parallel to provide a first signal stream;
a second set of photodiodes positioned on the first surface and surrounded by the wall, wherein:
the second set of photodiodes comprises at least four photodiodes, and
the photodiodes of the second set of photodiodes are connected to one another in parallel to provide a second signal stream; and
a cover located above the wall and comprising a single protruding convex surface configured to be located between tissue of the user and the first and second sets of photodiodes when the physiological measurement device is worn by the user,
wherein the physiological measurement device provides a plurality of optical paths, wherein each of the optical paths:
exits an emitter of the one or more emitters,
passes through tissue of the user,
passes through the single protruding convex surface, and
arrives at a corresponding photodiode of the at least one of the first or second sets of photodiodes, the corresponding photodiode configured to receive light emitted by the emitter after traversal by the light of a corresponding optical path of the plurality of optical paths and after attenuation of the light by tissue of the user.
2. The user-worn physiological measurement device of claim 1 further comprising:
preprocessing electronics configured to preprocess at least one of the first signal stream or the second signal stream.
3. The user-worn physiological measurement device of claim 2 , wherein the preprocessing comprises adapting the at least one of the first signal stream or the second signal stream.
4. The user-worn physiological measurement device of claim 3 , wherein the preprocessing further comprises amplifying the at least one of the first signal stream or the second signal stream.
5. The user-worn physiological measurement device of claim 4 , wherein the preprocessing further comprises converting the at least one of the first signal stream or the second signal stream from analog to digital.
6. The user-worn physiological measurement device of claim 2 , wherein the preprocessing electronics comprise at least:
a first common amplifier configured to receive the first signal stream from the first set of photodiodes at an input of the first common amplifier and at least amplify the first signal stream, and
a second common amplifier configured to receive the second signal stream from the second set of photodiodes at an input of the second common amplifier and at least amplify the second signal stream.
7. The user-worn physiological measurement device of claim 6 , wherein at least the photodiodes of the first set of photodiodes are arranged such that a first photodiode and a second photodiode are arranged across from each other on opposite sides of a central point along a first axis, and a third photodiode and a fourth photodiode are arranged across from each other on opposite sides of the central point along a second axis which is different from the first axis.
8. The user-worn physiological measurement device of claim 6 further comprising:
a plurality of windows, wherein each of the photodiodes of the first set of photodiodes and the second set of photodiodes has a corresponding window of the plurality of windows that allows light to pass through to the photodiode,
wherein each of the optical paths further:
passes through a corresponding window of the plurality of windows.
9. The user-worn physiological measurement device of claim 8 , wherein the single protruding convex surface protrudes a height between 1 millimeter and 3 millimeters.
10. The user-worn physiological measurement device of claim 9 further comprising:
one or more processors configured to:
receive a signal stream responsive to at least one of the first signal stream or the second signal stream, wherein the signal stream is responsive to at least a physiological parameter of the user; and
process the signal stream to determine measurements of the physiological parameter;
a network interface configured to communicate with a handheld computing device;
a touch-screen display configured to provide a user interface, wherein:
the user interface is configured to display indicia responsive to the measurements of the physiological parameter, and
an orientation of the user interface is configurable responsive to a user input; and
a storage device configured to at least temporarily store at least the measurements of the physiological parameter.
11. The user-worn physiological measurement device of claim 10 , wherein the physiological parameter comprises at least one of: pulse rate, glucose, oxygen, oxygen saturation, methemoglobin, total hemoglobin, carboxyhemoglobin, or carbon monoxide.
12. The user-worn physiological measurement device of claim 11 , wherein the attenuated light is reflected by the tissue.
13. The user-worn physiological measurement device of claim 12 further comprising:
a strap configured to position the physiological measurement device on the user, wherein the physiological measurement device comprises a single unit wearable by the user, the single unit encompassing at least: the one or more emitters, the first and second sets of photodiodes, the wall, the cover, the plurality of windows, the one or more processors, the network interface, and the storage device.
14. The user-worn physiological measurement device of claim 13 , wherein the network interface is configured to communicate at least the measurements of the physiological parameter to the handheld computing device.
15. The user-worn physiological measurement device of claim 14 , wherein the single protruding convex surface protrudes a height greater than 2 millimeters and less than 3 millimeters.
16. A user-worn physiological measurement device that defines a plurality of optical paths, the physiological measurement device comprising:
one or more emitters configured to emit light into tissue of a user;
a first set of photodiodes positioned on a first surface and surrounded by a wall that is operably connected to the first surface, wherein:
the first set of photodiodes comprises at least four photodiodes, and
the photodiodes of the first set of photodiodes are connected to one another in parallel to provide a first signal stream;
a second set of photodiodes positioned on the first surface and surrounded by the wall, wherein:
the second set of photodiodes comprises at least four photodiodes, and
the photodiodes of the second set of photodiodes are connected to one another in parallel to provide a second signal stream;
a cover located above the wall and comprising a single protruding convex surface configured to be located between tissue of the user and the first and second sets of photodiodes when the physiological measurement device is worn by the user;
a plurality of windows, wherein each of the photodiodes of the first set of photodiodes and the second set of photodiodes has a corresponding window of the plurality of windows that allows light to pass through to the photodiode;
preprocessing electronics configured to preprocess at least one of the first signal stream or the second signal stream, wherein the preprocessing electronics comprise at least:
a first common amplifier configured to receive the first signal stream from the first set of photodiodes at an input of the first common amplifier and at least amplify the first signal stream, and
a second common amplifier configured to receive the second signal stream from the second set of photodiodes at an input of the second common amplifier and at least amplify the second signal stream;
one or more processors configured to:
receive a signal stream responsive to at least one of the first signal stream or the second signal stream after preprocessing of the at least one of the first signal stream and the second signal stream, wherein the signal stream is responsive to at least a physiological parameter of the user, and wherein the physiological parameter comprises at least one of: pulse rate, glucose, oxygen, oxygen saturation, methemoglobin, total hemoglobin, carboxyhemoglobin, or carbon monoxide; and
process the signal stream to determine measurements of the physiological parameter;
a network interface configured to communicate at least the measurements of the physiological parameter to a handheld computing device;
a touch-screen display configured to provide a user interface, wherein the user interface is configured to display indicia responsive to the measurements of the physiological parameter;
a storage device configured to at least temporarily store at least the measurements of the physiological parameter; and
a strap configured to position the physiological measurement device on the user, wherein the physiological measurement device comprises a single unit wearable by the user, the single unit encompassing at least: the one or more emitters, the first and second sets of photodiodes, the wall, the cover, the plurality of windows, the one or more processors, the network interface, and the storage device,
wherein the physiological measurement device provides a plurality of optical paths, wherein each of the optical paths:
exits an emitter of the one or more emitters,
passes through tissue of the user,
passes through the single protruding convex surface and the corresponding window of the plurality of windows, and
arrives at a corresponding photodiode of the at least one of the first or second sets of photodiodes, the corresponding photodiode configured to receive light emitted by the emitter after traversal by the light of a corresponding optical path of the plurality of optical paths and after attenuation of the light by tissue of the user, and
wherein the attenuated light is reflected by the tissue.
17. A physiological measurement system comprising:
a user-worn physiological measurement device according to claim 16 ; and
a handheld computing device in communication with the user-worn physiological measurement device.