Light-based temperature calibration of physiological measurements

Abstract

Methods, systems, and devices for light-based temperature calibration for physiological measurements are described. The wearable device may perform a first measurement using the one or more light-emitting components having a wavelength at or above 1100 nanometers, estimate a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement, perform a second measurement using one or more sensors of the plurality of sensors, calibrate a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both and output a signal indicative of a calibrated version of the value of the second measurement.

Description

Oura271-l-WO-PCTLIGHT-BASED TEMPERATURE CALIBRATION OF PHYSIOLOGICAL MEASUREMENTSCROSS REFERENCES

[0001] The present Application for Patent claims the benefit of U.S. Provisional Patent Application No. 63 / 776,862 by Koskimaki et al., entitled “LIGHT-BASED TEMPERATURE CALIBRATION OF PHYSIOLOGICAL MEASUREMENTS,” filed March 24, 2025, assigned to the assignee hereof, and expressly incorporated by reference herein.FIELD OF TECHNOLOGY

[0002] The following relates to wearable devices and data processing, including light-based temperature calibration of physiological measurements.BACKGROUND

[0003] Some wearable devices may be configured to collect physiological data from users, including temperature data, heart rate data, and the like. However, measurements performed by one or more sensors of the wearable device may be improved.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] FIG. 1 shows an example of a wearable device diagram that supports lightbased temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0005] FIG. 2 shows an example of a wearable device diagram that supports lightbased temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0006] FIG. 3 shows an example of a wearable device diagram that supports lightbased temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0007] FIG. 4 shows an example of a graphical representation of temperature dependent absorption behavior of light at various wavelengths that supports light-based 1Attorney Docket No. 048624.00994Oura271-l-WO-PCTtemperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0008] FIGs. 5 and 6 illustrate examples of systems that support light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0009] FIG. 7 shows a block diagram of an apparatus that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0010] FIG. 8 shows a block diagram of a wearable device manager that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0011] FIG. 9 shows a diagram of a system including a device that supports lightbased temperature calibration of physiological measurements in accordance with aspects of the present disclosure.

[0012] FIG. 10 shows a flowchart illustrating methods that support light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure.DETAILED DESCRIPTION

[0013] Wearable devices may be configured to collect, monitor, and track physiological data associated with a user based on sensor measurements performed by the wearable device. Physiological data may be collected by emitting light from one or more light-emitting components of a wearable device, and measuring a reflected or transmitted light signal via one or more light-detecting components. The reflected or transmitted light signal may include one or more absorption peaks that may be correlated to a temperature of the user. However, the temperature may be representative of the skin temperature of the user rather than the temperature of the blood and / or surrounding tissue, which may lead to less accurate photopl ethy smogram (PPG) measurements and decreased signal quality.2Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0014] Techniques described herein focus on observing relative signal absorption peaks (e.g., signal amplitudes) at different wavelengths in order to determine a temperature or to detect relative changes in temperature of the blood and / or surrounding tissue and fluid within the finger or other body part of a user. The blood (or tissue) temperature may be used to calibrate other measurements performed by the wearable device. By determining the blood temperature using the optical measurements, techniques described herein may enable the wearable device to calibrate an optical measurement signal (e.g., PPG-based signal or spectral signature) using the measured blood temperature in order to determine other health metrics (e.g., blood sugar, hemoglobin, fat content, metabolism, blood oxygen saturation, etc.) with increased accuracy and signal quality. For example, observing that the temperature of the blood has increased, decreased, or remained steady over a certain duration may impact how the values of other PPG-based or other sensor-based measurements are calibrated or computed.

[0015] Specifically, the system (e.g., wearable device, user device, servers, etc.) may measure the signal absorption of emitted light at different wavelengths using one or more of the techniques and sensor arrangements as described herein. In one example, the wearable device may include a first sensor arrangement that includes two lightemitting components (e.g., light-emitting diodes (LEDs), laser diodes, or vertical cavity surface emitting lasers (VCSELs)) and a single light-detecting component (e.g., photodetector). The first light-emitting component may emit light at a wavelength (or wavelengths) above 1160 nanometer (nm), and the second light-emitting component may emit light at a wavelength (or wavelengths) above 1190 nm. The single lightdetecting component measures the respective light signals and compares the two signal absorption values (e.g., spectral points) to determine a change in the temperature of the blood.

[0016] In another example, the wearable device may include a second sensor arrangement that includes a single light-emitting component (e.g., LED) that covers a wide range of wavelengths around 1100 nm, and two light-detecting components (e.g., photodetectors). The first photodetector may be coated to filter out wavelengths below 1180 nm, and the second photodetector may be coated to filter out wavelengths above3Attorney Docket No. 048624.00994Oura271-l-WO-PCT1180 nm in order to determine the signal absorption points and estimate the change in the temperature of the blood. In another example, the wearable device may include a third sensor arrangement that includes a single light-emitting component (e.g., LED) that covers a wide range of wavelengths around 1100 nm, and a single light-detecting component (e.g., spectrometer). The spectrometer may split the specific wavelengths spatially to generate signal absorption points, which can be used to estimate the change in temperature of the blood.

[0017] Using the blood temperature to calibrate other measurements may be based on the principle that water absorbs differently in relation to temperature in different wavelengths. Thus, improvements to measuring temperature of the blood may be advantageous to calibrate the spectral signature signals and enable highly accurate determination of various metrics, such as blood sugar, hemoglobin, fat content, metabolism, blood oxygen saturation, among other examples. Furthermore, based on determined temperature measurements performed via the light-based sensors, the wearable device may be configured to dynamically adjust operational parameters of the various sensors of the wearable device (e.g., wavelengths of light used, power provided to the light-emitting components, etc.) in order to further improve the quality of collected physiological measurements.

[0018] Instead of incorporating a separate temperature sensor within the wearable device, the temperature of the blood may be measured by using broad spectrum light (e.g., wide spectrum light) via one or more light-emitting components and one or more and light-receiving components. In such cases, measuring blood temperature with the sensor arrangements described herein may result in more accurate measurements and lead to less design and manufacturing complexity as the wearable device may not need an additional temperature sensor to be implemented. Thus, techniques described herein may reduce the manufacturing cost of wearable devices by leveraging existing lightbased sensors to perform temperature measurements instead of incorporating additional temperature sensors. Moreover, the described light-based temperature measurements may be more accurate than estimating the temperature of the blood or surrounding tissue using temperature sensors that touch the surface of the skin. Using the temperature measurement techniques described herein, the system may calibrate aspects4Attorney Docket No. 048624.00994Oura271-l-WO-PCTof measured PPG signals and / or aspects of the metrics or values that are derived from the measured light signals. The PPG measurements depend on the amplitude of the PPG signal, thereby increasing the accuracy of the PPG measurement being closer to the actual blood temperature inside the finger rather than a temperature of the skin surface.

[0019] Aspects of the disclosure are initially described in the context of wearable device diagrams and a graphical representation of the temperature-dependent absorption of light at various wavelengths. Additional aspects of the disclosure are described in the context of systems supporting physiological data collection from users via wearable devices. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to light-based temperature calibration of physiological measurements.

[0020] FIG. 1 shows an example of a wearable device diagram 100 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The wearable device diagram 100 may illustrate examples of wearable devices as described herein. Although the wearable devices are illustrated as rings in FIG. 1, aspects and components of the wearable devices illustrated in FIG. 1 may be implemented in any type of wearable device (e.g., a watch, a bracelet, a necklace, and the like).

[0021] In some examples, the wearable device 105 may include an inner housing 110 and an outer housing 107, although other arrangements are also possible. One or more sensors may be embedded between the inner housing 110 and the outer housing 107 or otherwise coupled with or arranged on the inner housing 110 and / or the outer housing 107. The one or more sensors may include or be comprised of combinations of one or more light-emitting components 120 and one or more light-detecting components 115. The light-emitting components 120 may be an example of a LED, a VSCEL, a laser diode, or a combination thereof. The light-detecting components 115 may be configured for collecting physiological measurements as described herein (e.g., heart rate, blood glucose, blood pressure, oxygen saturation, among other examples). The wearable device 105 in wearable device diagram 100 may include an electronic substrate 112, such as a printed wiring board (PWB) or printed circuit board (PCB) that is coupled with the one or more sensors.5Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0022] One or more sensors may be embedded in or otherwise coupled with or arranged on the electronic substrate 112. For example, the electronic substrate 112 may support one or more light-emitting components 120 and a light-detecting component 115. The light-detecting component 115 may be an example of a photodetector. The wearable device 105 may include a first light-emitting component 120-a, which may emit first light 130-a received by light-detecting component 115. The wearable device 105 may include second light-emitting component 120-b, which may emit second light 130-b received by light-detecting component 115. Although not shown in the figure for clarity, the first light 130-a and the second light 130-b may travel through at least a portion of the tissue of the finger upon which the wearable device 105 is worn, and the first light 130-a and the second light 130-b may be at least partially absorbed by the tissue and / or blood within the finger, while a portion of the first light 130-a and second light 130-b reflects may pass out of the tissue and may be detected by the light-detecting component 115. In this regard, the first light-emitting component 120-a may support a first optical channel for physiological measurements between the first light-emitting component 120-a and the light-detecting component 115, and the second light-emitting component 120-b may support a second optical channel for physiological measurements between the second light-emitting component 120-b and the light-detecting component 115.

[0023] In some cases, first light-emitting component 120-a may be a LED, VSCEL, laser diode, or the like, which may emit first light 130-a that is scattered and absorbed by the skin or tissue of a user of the wearable device 105 (e.g., reflective and / or transmissive measurements). The first light 130-a may have a first wavelength at or above 1160 nm. For example, the first light 130-a may have a first wavelength of 1165 nm.

[0024] In some cases, second light-emitting component 120-b may be a LED, VSCEL, laser diode, or the like, which may emit second light 130-b that is scattered and absorbed by the skin of a user of the wearable device 105 (e.g., reflective and / or transmissive measurements). The second light 130-b may have a second wavelength at or above 1190 nm. For example, the second light 130-b may have a second wavelength of 1195 nm. The system may measure the first light 130-a and second light 130-b via a6Attorney Docket No. 048624.00994Oura271-l-WO-PCTsingle light-detecting component 115 which may increase the reliability of the measurement in addition to measuring the temperature of the blood (and / or surrounding tissue) using two different light sources (e.g., first light-emitting component 120-a and second light-emitting component 120-b). In such cases, the wearable device 105 may include a 2:1 relationship between the light-emitting components 120 and the lightdetecting component 115.

[0025] In some aspects, separate spectral fingerprint or PPG signals may be acquired along each of the respective optical channels. Moreover, in some implementations, the first light-emitting component 120-a may be configured to generate first light 130-a with a different wavelength as compared to the second light 130-b generated by the second light-emitting component 120-b, which may further improve a diversity of measurements (e.g., PPG signals) acquired by the wearable device 105.

[0026] In some cases, light-detecting component 115 may detect light emitted from one or more light-emitting components 120 used for physiological measurements. For example, the light-detecting component 115 may be used for both measurements using 1165 nm wavelength and 1195 nm wavelength. The PPG signals may be based on a combination of transmissive and reflective light. The light-detecting component 115 may include germanium, silicon, indium, gallium, arsenic, or a combination thereof. For example, the light-detecting component 115 may include indium, gallium, and arsenic.

[0027] In some cases, each of the first light-emitting component 120-a, lightdetecting component 115, and second light-emitting component 120-b may be positioned at different positions relative to an axis of the wearable device 105 and along an inner surface 117 (e.g., inner curved surface, inner circumferential surface) of the wearable device 105. In some examples, the first light-emitting component 120-a and the second light-emitting component 120-b may be positioned at the same radial position relative to an axis of the wearable device 105 and along the inner surface 117 of the wearable device. For example, the first light-emitting component 120-a and second light-emitting component 120-b may be adjacent to each other along the inner surface 117 of the wearable device 105. In some examples, the light-detecting component 115 may be positioned at a radial position opposite of the light-emitting 7Attorney Docket No. 048624.00994Oura271-l-WO-PCTcomponents 120. The light-detecting component 115 may be positioned radially closer to the second light-emitting component 120-b in order to make the distance between the light-detecting component 115 and the second light-emitting component 120-b shorter. In some cases, the positions of the first light-emitting component 120-a and second light-emitting component 120-b may be switched.

[0028] In some cases, the inner housing 110 may include a dome structure (or a raised portion that is non-dome shaped) over the one or more light-emitting components 120, the light-detecting component 115, or both. For example, the wearable device 105 may include dome structures over light-emitting components 120, light-detecting component 115, or both to improve contact with the skin. In some other cases, there may be a window for the light-emitting components 120 to emit light 130. In other cases, the inner housing 110 may not include a dome structure or other raised portions. In some cases, light-emitting component 120-a and second light-emitting component 120-b may be flush with the surface of the inner housing 110, such that the skin may make direct contact with first light-emitting component 120-a and second light-emitting component 120-b. Further, light propagating inside the skin (e.g., finger tissue) may be coupled to the light-detecting component optics through skin to inner housing 110 interface.

[0029] The wearable device 105 may use the light propagation from the lightemitting components 120 to the light-detecting components 115 through tissue for PPG-based physiological measurements (e.g., heart rate) or other light-based measurements (e.g., SpO2 measurements) among other examples, as described herein. First light 130-a may penetrate the skin to a different depth than second light 130-b due to the different wavelengths.

[0030] In some implementations, a single light-detecting component 115 may be used together with multiple light-emitting components 120 to save cost and space. By measuring the signals (e.g., at light-detecting component 115), it may be possible to use light-emitting components 120 that have sufficient optical paths during rapid motion and reduce battery consumption.8Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0031] The wearable device 105 may be an example of a wearable ring device. For example, the PPG signals acquired along the respective channels illustrated in the wearable device diagram 100 may be acquired as a combination of the transmissive and reflective light transmitted through the skin of the finger. In such cases, the system may measure blood temperature measurements at different locations of the finger by transmitting or reflecting the light through a portion of the finger (e.g., widest portion of the finger) where the smaller arteries, arterioles, and capillaries are located.Comparatively, other portions of the body (e.g., top of the wrist) may not include large arteries and may include bone and other bodily material which may interfere with physiological measurements collected by some wearable devices. As such, some other wearable devices, such as wearable devices worn around the wrist, may be unable to acquire physiological data based on blood flow within arteries, which may result in inferior physiological measurements as compared to measurements acquired using a wearable ring device, thereby decreasing an efficiency and reliability of acquired physiological measurements.

[0032] In some cases, the system may calibrate the measurements for different ring sizes and for different light-emitting component 120 currents. The light-emitting component 120 properties may change as higher currents or different currents may be used. For example, a smaller ring size may include smaller light-emitting component 120 currents as compared to a larger ring size. If a larger light-emitting component 120 current were to be used with a smaller ring size, the light-detecting component 115 may be saturated such that the light-detecting component 115 may be unable to detect the first light 130-a or second light 130-b. Using a smaller light-emitting component 120 current may decrease the power consumption and increase the battery life of the wearable device 105.

[0033] The wearable device 105 may support techniques for light-based temperature calibration of physiological measurements. The wearable device 105 may estimate the temperature of water in the user’s blood based on performing optical measurements. The wearable device 105 calibrates the measured bio-signal using the estimated temperature to determine other health metrics with higher accuracy. In some cases, the wearable device 105 may estimate the actual value of the temperature of water in the9Attorney Docket No. 048624.00994Oura271-l-WO-PCTuser’s blood, a change in temperature of the water in the user’s blood (e.g., whether the temperature of the user’s blood increased, decreased, or stayed the same), an actual value of the change in water temperature of the user’s blood, or a combination thereof. In some cases, the wearable device 105 may estimate the actual value of the temperature of water in surrounding tissue, a change in temperature of water in surrounding tissue, an actual value of the change in the temperature of water in surrounding tissue, or a combination thereof.

[0034] The wearable device 105 may include a battery configured to provide power to the plurality of sensors, electronic circuitry configured to electrically couple the battery with the plurality of sensors, and one or more processors communicatively coupled with the battery and the plurality of sensors.

[0035] The wearable device 105 may perform a first measurement using the one or more light-emitting components 120 having a wavelength at or above 1100 nm. The wearable device 105 may estimate a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit (e.g., finger) of the user based on the first measurement. In some cases, the wearable device 105 may estimate a change in temperature of water in blood, or a change in temperature of water in surrounding tissue, or both, of a digit (e.g., finger) of the user based on the first measurement.

[0036] The wearable device 105 may perform a second measurement using one or more sensors of the plurality of sensors (e.g., light-based sensors or other forms of sensors) and calibrate a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both. The wearable device 105 may output a signal indicative of a calibrated version of the value of the second measurement. Further, in some aspects, the wearable device may be configured to dynamically adjust operational parameters of the various sensors of the wearable device (e.g., wavelengths of light used, power provided to the light-emitting components, etc.) based on determined temperature measurements performed via the light-based sensors in order to further improve the quality of collected physiological measurements. For example, based on the determined temperature of the blood and / or surrounding tissue, the wearable device may adjust which wavelengths of light are used for subsequent physiological measurements.10Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0037] At a first instance, the first light-emitting component 120-a of the one or more light-emitting components may emit first light 130-a having a first wavelength at or above 1160 nm. The light-detecting component 115 may measure a first absorption spectrum point based on the first light 130-a having the wavelength at or above 1160 nm. At the first instance, or shortly after the first instance, the second light-emitting component 120-b may emit second light 130-b having a second wavelength at or above 1190 nm. The light-detecting component 115 may measure a second absorption spectrum point on the second light 130-b having the wavelength at or above 1190 nm. The second light-emitting component 120-b may emit the second light 130-b before, after, or at same time that the first light-emitting component 120-a emits the first light 130-a.

[0038] In some cases, a full absorption spectrum may not be measured with a single wavelength source (e.g., light-emitting components 120), as the light-detecting component 115 may be unable to separate source wavelengths from each other. The spectrum point may be an example of a single point on a full absorption curve. In such cases, the full absorption curve may include a plurality of spectrum points generated from emitting light 130 at various instances. In some cases, the full absorption curve may be measured with multiple different wavelength sources (e.g., light-emitting components 120) as a combination of multiple absorption spectrum points.

[0039] The ratio of the two absorption spectrum points may be an example of the absorption coefficients at a first time. For example, the system may determine, for the first light 130-a having the first wavelength, a first absorption coefficient value at a first instance based on the first absorption spectrum point and the second absorption spectrum point. In such cases, the first absorption coefficient value for the first light 130-a may be an example of the first absorption spectrum point divided by the second absorption spectrum point.

[0040] At a second instance after the first instance, the first light-emitting component 120-a of the one or more light-emitting components 120 may emit first light 130-a having a first wavelength at or above 1160 nm. The light-detecting component 115 may measure a third absorption spectrum point based on the first light 130-a having the wavelength at or above 1160 nm. At the second instance, the second light-emitting 11Attorney Docket No. 048624.00994Oura271-l-WO-PCTcomponent 120-b may emit second light 130-b having a second wavelength at or above 1190 nm. The light-detecting component 115 may measure a fourth absorption spectrum point on the second light having the wavelength at or above 1190 nm. The second lightemitting component 120-b may emit the second light 130-b before, after, or at same time that the first light-emitting component 120-a emits the first light 130-a. In such cases, the system may determine, for the first light 130-a having the first wavelength, a second absorption coefficient value at the second instance based at least in part on the third absorption spectrum point and the fourth absorption spectrum point. In such cases, the second absorption coefficient value for the first light 130-a may be an example of the third absorption spectrum point divided by the fourth absorption spectrum point.

[0041] The system may determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, as described with reference to FIG. 4, a difference between the first absorption coefficient value and the second absorption coefficient value for the first light 130-a having the first wavelength. The change in the absorption coefficients for the first light 130-a having the first wavelength may be indicative of a change in the temperature of the water of the blood and / or the surrounding tissue in the finger of the user. The system may include the wearable device 105, one or more user devices, a network, one or more servers, or a combination thereof, as described with reference to FIGs. 5 and 6.

[0042] In some cases, the system (e.g., the wearable device 105, one or more user devices, a network, one or more servers, or a combination thereof) may verify the change in the absorption coefficients, and therefore the change in the temperature of the water, by calculating the absorption coefficients for the second light 130-b having the second wavelength. For example, the system (e.g., the wearable device 105, one or more user devices, or a combination thereof) may determine, for the second light 130-b having the second wavelength, a first absorption coefficient value at the first instance based on the first absorption spectrum point and the second absorption spectrum point. In such cases, the first absorption coefficient value for the second light 130-b may be an example of the second absorption spectrum point divided by the first absorption spectrum point. The system (e.g., the wearable device 105, one or more user devices, or a combination thereof) may determine, for the second light 130-b having the second12Attorney Docket No. 048624.00994Oura271-l-WO-PCTwavelength, a second absorption coefficient value at the second instance based on the third absorption spectrum point and the fourth spectrum point. In such cases, the second absorption coefficient value for the second light 130-b may be an example of the fourth absorption spectrum point divided by the third absorption spectrum point.

[0043] The system may determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, as described with reference to FIG. 4, a difference between the first absorption coefficient value and the second absorption coefficient value for the second light 130-b having the second wavelength. The change in the absorption coefficients for the second light 130-b having the second wavelength may be indicative of a change in the temperature of the water in the blood and / or the surrounding tissue in the finger of the user.

[0044] The system (e.g., the wearable device 105, one or more user devices, the one or more servers, or a combination thereof) may determine a change in temperature in the water of the user’s blood and / or surrounding tissue that corresponds to the difference between the first absorption coefficient value and the second coefficient value. In such cases, the system may estimate the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user based on determining the change in temperature.

[0045] The measured absorption coefficient value at one wavelength (e.g., the first wavelength) may be greater or smaller than absorption coefficient value at another wavelength (e.g., the second wavelength) depending on the water temperature. It may be difficult to separate pure water absorption coefficient values from the measured signals in practice as there may be other factors than water causing light absorption in the tissue (e.g., lipids, bone structure within the finger, and the like). In some cases, the system (e.g., the wearable device 105, one or more user devices, or a combination thereof) may analyze measured DC signals with the two wavelengths (e.g., the first wavelength and the second wavelength), but the system may be unable to determine which DC signal is higher or lower. That is, the system (e.g., the wearable device 105, one or more user devices, or a combination thereof) may measure absorption coefficient value changes at the two wavelengths (e.g., the first wavelength and the second wavelength) to determine whether the absorption coefficient value changes relative to 13Attorney Docket No. 048624.00994Oura271-l-WO-PCTeach other, which indicates a change in water temperature of the blood and / or surrounding tissue.

[0046] In such cases, the techniques described herein may describe how an absorption coefficient value is determined (e.g., based on the ratio of two spectrum points) for a particular wavelength at a first instance, and at a second instance, a different absorption coefficient is determined for the same wavelength. The system (e.g., the wearable device 105, one or more user devices, or a combination thereof) may identify how those absorption coefficient values change over time (e.g., increase or decrease), and based on the knowledge of how the absorption coefficient values change, the system may determine if temperature of water changed (e.g., increased or decreased).

[0047] In some systems, a perfusion index may be used to determine an effect of blood flow in the finger in the measurements. However, by taking the measurements without knowledge of the temperature of the blood within the finger, the system may be unable to determine whether the signal quality is weak or strong. The skin temperature may be measured in DC levels, but the temperature of the skin may be different than the temperature of the blood. However, skin temperature measurements may not be used as a calibration factor for other measurements because the temperature of the blood is different from the temperature of the skin.

[0048] FIG. 2 shows an example of a wearable device diagram 200 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The wearable device diagram 200 may implement, or be implemented by, aspects of the wearable device diagram 100. For example, wearable device diagram 200 may illustrate examples of wearable devices 105, as described with reference to FIG. 1. Although the wearable devices are illustrated as rings in FIG. 2, aspects and components of the wearable devices illustrated in FIG. 2 may be implemented in any type of wearable device (e.g., a watch, a bracelet, a necklace, and the like).

[0049] The wearable device 205 in wearable device diagram 200 may include an electronic substrate 212, such as a PWB or PCB, an inner housing 210, and outer14Attorney Docket No. 048624.00994Oura271-l-WO-PCThousing 207, and one or more sensors embedded between the inner housing 210 and the outer housing 207 or otherwise coupled with or arranged on the inner housing 210 and / or the outer housing 207. The one or more sensors may include or be comprised of combination of a light-emitting component 220 and one or more light-detecting components 215 (e.g., light-detecting components 215-a and 215-b). The single lightemitting component 220 (e.g., LED) covers a wide range of wavelengths around 1100 nm. The light-emitting component 220 may include a combination of one or more emitter chips (e.g., a LED, a VSCEL, a laser diode, or a combination thereof) inside a single source package to form a wide range light source. The light-detecting components 215 may be configured for collecting physiological measurements as described herein (e.g., heart rate, blood glucose, blood pressure, oxygen saturation, among other examples).

[0050] The one or more sensors may be embedded in or otherwise coupled with or arranged on the electronic substrate 212. For example, the electronic substrate 212 may support the light-emitting component 220 (e.g., first light-emitting component 220) and light-detecting components 215. The light-detecting components 215 may be an example of photodetectors. The light-detecting components 215 may include germanium, silicon, or both. The wearable device 205 may include light-emitting component 220, which may emit light 230 received by first light-detecting component 215-a. The light-emitting component 220 may emit light 230 received by second lightdetecting component 215-b. Although not shown in the figure for clarity, the light 230 travels through at least a portion of the tissue of the finger upon which the wearable device 205 is worn, and the light 230 is at least partially absorbed by the tissue and / or blood within the figure, while a portion of the light 230 reflects and passes out of the tissue and is detected by one or more light-detecting components 215. In this regard, the light-emitting component 220 may support a first optical channel for physiological measurements between the light-emitting component 220 and the light-detecting component 215-a and a second optical channel for physiological measurements between the light-emitting component 220 and the second light-detecting component 215-b. The system may measure the light 230 via two light-detecting components 215 which may increase the diversity and reliability of the measurement. The system may include the15Attorney Docket No. 048624.00994Oura271-l-WO-PCTwearable device 205, one or more user devices, a network, one or more servers, or a combination thereof, as described with reference to FIGs. 5 and 6.

[0051] In some cases, light-emitting component 220 may be a LED, VSCEL, laser diode, or the like, which may emit light 230 that is scattered and absorbed by the skin or tissue of the user of the wearable device 205 (e.g., reflective and / or transmissive measurements). The light 230 may have a wavelength at or above 1100 nm. For example, the light 230 may have a wavelength between 1164 nm and 1184 nm. In such cases, the wearable device 205 may utilize a single LED (or other light source type) with a wide spectrum peak that covers a wavelength range of 1164 nm to 1184 nm.

[0052] The wearable device 205 may measure the light 230 via two light-detecting components 215 which may increase the reliability of the measurement in addition to measuring the temperature of the blood (and / or surrounding tissue) using two different photodetectors (e.g., first light-detecting component 215-a and second light-detecting component 215-b). In such cases, the wearable device 205 may include a 1:2 relationship between the light-emitting component 220 and the light-detecting components 215.

[0053] As described herein, the two light-detecting components 215 may include coatings that divide the spectral range that they receive into two different spectral points from the light-emitting component 220. A first point may be closer to light 230 having a wavelength of 1164 nm, and a second point may be closer to light 230 having a wavelength of 1184 nm. For example, the light-emitting component 220 may emit light 230 where each of the light-detecting components 215 measures different signals that may be connected to specific points (e.g., absorption spectrum points) in the absorption curve (e.g., absorption spectrum range). In some cases, the light-detecting components 215 may be coated to forcefully view a narrower range of the light 230.

[0054] In some cases, each of the light-emitting component 220, light-detecting component 215-a, and light-detecting component 215-b may be positioned at different positions relative to an axis of the wearable device 205 and along an inner surface 217 of the wearable device 205. In some examples, the light-detecting component 215-a may be positioned at a radial position opposite of the light-detecting component 215-b.16Attorney Docket No. 048624.00994Oura271-l-WO-PCTIn some cases, light-emitting component 220 may be flush with the surface of the inner housing 210, such that the skin may make direct contact with first light-emitting component 120-a and second light-emitting component 120-b. Further, light propagating inside the skin or tissue may be coupled to the light-detecting component optics through skin to inner housing 210 interface.

[0055] In some implementations, a single light-emitting component 220 may be used together with multiple light-detecting components 215 to save cost and space. By measuring the signals (e.g., at light-detecting component 215), it may be possible to use light-emitting component 220 that has sufficient optical paths during rapid motion and reduce battery consumption.

[0056] Wearable device 205 may support techniques for light-based temperature calibration of physiological measurements. The wearable device 205 may estimate the temperature of water in the user’s blood and / or surround tissue based on performing optical measurements. The wearable device 205 calibrates the measured bio-signal using the estimated temperature to determine other health metrics with higher accuracy, as described herein. In some cases, the wearable device 205 may estimate a change in water temperature of the user’s blood and / or surrounding tissue based on performing optical measurements. The wearable device 205 may determine whether a change in temperature of the user’s blood and / or surrounding tissue occurred based on performing optical measurements. In such cases, the wearable device 205 may calibrate the measured bio-signal using the estimated temperature, the estimated change in temperature, and / or determining whether a change in temperature occurred.

[0057] The wearable device 205 may perform a first measurement using the lightemitting component 220 having a wavelength at or above 1100 nm. For example, at a first instance, or shortly after the first instance, the light-emitting component 220 may emit light 230 having a wavelength at or above 1100 nm. The first light-detecting component 215-a may measure a first absorption spectrum point based on the light 230 having the wavelength at or above 1100 nm. The first light-detecting component 215-a may be coated to filter out light 230 having wavelengths below 1180 nm. For example, the first light-detecting component 215-a includes a first filter configured to allow light 230 having a wavelength below 1180 nm to pass through the first filter and block the 17Attorney Docket No. 048624.00994Oura271-l-WO-PCTlight 230 having the wavelength at or above 1180 nm from passing through the first filter. In such cases, if a spectrum point is measured via the first light-detecting component 215-a, then the system (e.g., the wearable device 205) may determine that the light 230 has a wavelength below 1180 nm.

[0058] At the first instance, or shortly after the first instance, the second lightdetecting component 215-b may measure a second absorption spectrum point based on the light 230 having the wavelength at or above 1100 nm. The second light-detecting component 215-b may be coated to filter out light 230 having wavelengths above 1180 nm. For example, the second light-detecting component 215-b includes a second filter configured to allow the light 230 having the wavelength at or above 1180 nm to pass through the second filter and block the light 230 having the wavelength below 1180 nm from passing through the second filter. In such cases, if a spectrum point is measured via the second light-detecting component 215-b, then the system (e.g., the wearable device 205) may determine that the light 230 has a wavelength above 1180 nm. The wearable device 205 may determine, for the light 230 having the wavelength at or above 1100 nm, a first absorption coefficient value at the first instance based on the first absorption spectrum point and the second absorption spectrum point.

[0059] The ratio of the two absorption spectrum points may be an example of the absorption coefficient at the first instance. For example, the system (e.g., the wearable device 205, the one or more user devices, or a combination thereof) may determine, for the light 230 having the first wavelength, a first absorption coefficient value at the first instance based on the first absorption spectrum point and the second absorption spectrum point. In such cases, the first absorption coefficient value for the light 230 may be an example of the first absorption spectrum point divided by the second absorption spectrum point.

[0060] At a second instance, or shortly after the second instance, the first lightemitting component 220 may emit light 230 having a wavelength at or above 1100 nm. The first light-detecting component 215-a may measure a third absorption spectrum point based on the light 230 having the wavelength at or above 1100 nm at the second instance. At the second instance, the second light-detecting component 215-b may18Attorney Docket No. 048624.00994Oura271-l-WO-PCTmeasure a fourth absorption spectrum point based on the light 230 having the wavelength at or above 1100 nm at the second instance.

[0061] The wearable device 205 may determine, for the light 230 having the wavelength at or above 1100 nanometers, a second absorption coefficient value at the second instance based on the third absorption spectrum point and the fourth absorption spectrum point. In such cases, the second absorption coefficient value for the light 230 may be an example of the third absorption spectrum point divided by the fourth absorption spectrum point. As further described with reference to FIG. 4, the wearable device 205 may determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the light 230 having the wavelength at or above 1100 nanometers.

[0062] In such cases, the wearable device 205 may determine a change in temperature that corresponds to the difference between the first absorption coefficient value and the second absorption coefficient value and estimate the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user based on determining the change in temperature, as described herein with reference to FIG. 4. As described herein, once the temperature and / or temperature change of the blood or tissue is determined, the temperature and / or temperature change may be used for calibration techniques, such as calibrating other measurements taken by the wearable device 205. For example, the wearable device 205 may calibrate one or more PPG signals using the estimated temperature, the estimated change in temperature, and / or determining whether a change in temperature occurred.

[0063] FIG. 3 shows an example of a wearable device diagram 300 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The wearable device diagram 300 may implement, or be implemented by, aspects of the wearable device diagram 100, wearable device diagram 200, or both. For example, wearable device diagram 300 may illustrate examples of wearable devices 305, as described with reference to FIGs. 1 and 2.Although the wearable devices 305 are illustrated as rings in FIG. 3, aspects and19Attorney Docket No. 048624.00994Oura271-l-WO-PCTcomponents of the wearable devices illustrated in FIG. 3 may be implemented in any type of wearable device (e.g., a watch, a bracelet, a necklace, and the like).

[0064] The wearable device 305 in wearable device diagram 300 may include an inner housing 310, an outer housing 307, and one or more sensors embedded between the inner housing 310 and the outer housing 307 or otherwise coupled with or arranged on the inner housing 310 and / or the outer housing 307. The one or more sensors may include or be comprised of a combination of light-emitting component 320 and lightdetecting component 315. The single light-emitting component 320 covers a wide range of wavelengths around 1100 nm. The light-emitting component 320 may include a combination of one or more emitter chips (e.g., a LED, a VSCEL, a laser diode, or a combination thereof) inside a single source package to form a wide range light source. The light-detecting component 315 may be an example of spectrometer. The spectrometer may split the specific wavelengths spatially to generate two or more signal absorption points (e.g., absorption curves) and estimate the corresponding temperature of the blood and / or surrounding tissue for the signal absorption peaks. The lightdetecting component 315 may mechanically move a mirror to see different parts of the wavelength across the spectrum.

[0065] The light-emitting component 320 may emit light 330 received by the lightdetecting component 315. Although not shown in the figure for clarity, the light 330 travels through at least a portion of the tissue of the finger upon which the wearable device 305 is worn, and the light 330 is at least partially absorbed by the tissue and / or blood within the figure, while a portion of the light 330 reflects and passes out of the tissue and is detected by the light-detecting component 315. In this regard, the lightemitting component 320 may support an optical channel for physiological measurements between the light-emitting component 320 and the light-detecting component 315. The wearable device 305 may measure the light 330 via the lightdetecting component 315 (e.g., spectrometer) which may provide quick and precise measurements across various wavelengths of light. In some implementations, a single light-emitting component 320 may be used together with the single light-detecting component 315 to save cost and space. By measuring the signals (e.g., at light-detecting component 315), it may be possible to use a single light-emitting component 320 that.20Attorney Docket No. 048624.00994Oura271-l-WO-PCTIn such cases, the wearable device 305 may include a 1 : 1 relationship between the lightemitting component 320 and the light-detecting component 315. In some cases, the light-detecting component 315 may be an example of a photodetector with a filter configured to be modulated by voltage to allow the sampling of two different wavelengths at different times. In such cases, the light-detecting component 315 may include a voltage controlled filter on top of the single photodetector, thereby allowing the wearable device 305 to sample two or more wavelengths with a single lightdetecting component 315 and a single light-emitting component 320.

[0066] In some cases, light-emitting component 320 may be a LED, VSCEL, laser diode, or the like, which may emit light 330 that is scattered and absorbed by the skin or tissue of the user of the wearable device 305 (e.g., reflective and / or transmissive measurements). The light 330 may have a wavelength at or above 1100 nm. For example, at a first instance, or shortly after the first instance, the light-emitting component 320 may emit light 330 having the wavelength at or above 1100 nm. The light-detecting component 315 may measure a plurality of absorption spectrum points based on the light 330 having the wavelength at or above 1100 nm. The wearable device 305 may determine, from the plurality of absorption spectrum points, a first absorption curve corresponding to the light 330 having the wavelength at or above 1100 nanometers at the first instance. The first absorption curve may include the plurality of absorption spectrum points. In such cases, a series of the plurality of spectrum points may generate the first absorption curve.

[0067] At a second instance, or shortly after the second instance, the light-emitting component 320 may emit light 330 having the wavelength at or above 1100 nm. The light-detecting component 315 may measure a plurality of absorption spectrum points based on the light having the wavelength at or above 1100 nanometers at the second instance. The wearable device 305 may determine, from the plurality of absorption spectrum points, a second absorption curve corresponding to the light 330 having the wavelength at or above 1100 nanometers at the second instance. The second spectrum absorption curve may include the plurality of absorption spectrum points that generate the absorption curve. The shapes of the absorption curves may be based on whether the21Attorney Docket No. 048624.00994Oura271-l-WO-PCTplurality of absorption spectrum points decrease or increase over time (e.g., between multiple iterations of instances).

[0068] The system (e.g., the wearable device 305, one or more user devices, a network, one or more servers, or a combination thereof) may determine a difference between a first shape of the first absorption curve and a second shape of the second absorption curve. For example, the overall shape and / or curvature of the first absorption curve may be different than the overall shape and / or curvature of the second absorption curve. In some case, the first absorption curve may have a different quantity of peaks than the second absorption curve, the peaks of the first absorption curve may have a higher or lower amplitude than the peaks of the second absorption curve, the first absorption curve may have a different slope than the second absorption curve, or a combination thereof.

[0069] The system may include the wearable device 305, one or more user devices, a network, one or more servers, or a combination thereof, as described with reference to FIGs. 5 and 6. For example, the system may determine a change in temperature that corresponds to the difference between the first shape of the first absorption curve and the second shape of the second absorption curve. In such cases, if the system determines a difference between the shapes of the absorption curves, then the system may determine that the temperature of the water in the blood and / or surrounding tissue has changed. The system may estimate the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user based on determining the change in temperature. As described herein, once the temperature and / or temperature change of the blood or tissue is calculated, the temperature and / or temperature change may be used to calibrate other measurements taken by the wearable device 305. For example, the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both may be used to calibrate a value of a second measurement performed by the wearable device 305.

[0070] FIG. 4 shows an example of a graphical representation 400 of temperature dependent absorption behavior of light at various wavelengths that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The graphical representation 400 may implement, or be22Attorney Docket No. 048624.00994Oura271-l-WO-PCTimplemented by, aspects of the wearable device diagram 100, wearable device diagram 200, wearable device diagram 300, or a combination thereof.

[0071] The graphical representation 400 may be an example of an absorption spectra of water. For example, the graphical representation 400 may include a first temperature curve 405-a, a second temperature curve 405-b, and a third temperature curve 405-c. The first temperature curve 405-a may be an example of how the absorption spectra of water varies for a temperature of 30 degrees Celsius, the second temperature curve 405-b may be an example of how the absorption spectra of water varies for a temperature of 35 degrees Celsius, the third temperature curve 405-c may be an example of how the absorption spectra of water varies for a temperature of 40 degrees Celsius.

[0072] In some cases, the graphical representation 400 may illustrate how the absorption coefficient varies based on the temperature at different transmission wavelengths 410. For example, the graphical representation 400 may include a first wavelength 410-a and a second wavelength 410-b. The first wavelength 410-a may be an example of light having a wavelength of 1165 nm. The second wavelength 410-b may be an example of light having a wavelength of 1195 nm.

[0073] The graphical representation 400 may illustrate how absorption peaks in the temperature curves 405 shift as a function of wavelength for different water temperatures. For example, as the water molecules gain more energy, the distance between water molecules increases and the wavelengths of light may be absorbed differently based on the distance between water molecules.

[0074] The measured absorption coefficient value 415 at one wavelength 410 may be greater or smaller than the absorption coefficient value 415 at another wavelength 410 depending on the water temperature. For example, the system may measure how the absorption coefficient value 415 changes over time (e.g., comparing a first measurement to a second measurement) at the two wavelengths 410 and determine if the absorption coefficient values have increased or decreased relative to each other, which indicates a change in water temperature and therefore a change in temperature of water in the blood, the surrounding tissue, or both in the finger of the user. The system may include23Attorney Docket No. 048624.00994Oura271-l-WO-PCTthe wearable device, one or more user devices, a network, one or more servers, or a combination thereof, as described with reference to FIGs. 1, 2, 5 and 6.

[0075] As described with reference to FIGs. 1 and 2, the system (e.g., the wearable device, the one or more user devices, or a combination thereof) may determine the absorption coefficient values 415 based on a ratio of absorption spectrum points. For example, at a first instance, the system may determine, for the first light having the first wavelength 410-a, a first absorption coefficient value 415-a based on the first absorption spectrum point and the second absorption spectrum point. At a second instance, the system may determine, for the first light having the first wavelength 410-a, a second absorption coefficient value 415-b at the second instance based on the third absorption spectrum point and the fourth absorption spectrum point.

[0076] The system (e.g., the wearable device, the one or more user devices, or a combination thereof) may determine, from the graphical representation 400, a difference between the first absorption coefficient value 415-a and the second absorption coefficient value 415-b for the first light having the first wavelength 410-a. The change in the absorption coefficient values 415 for the first light having the first wavelength 410-a may be indicative of a change in the temperature of the water, and therefore the change in temperature of the blood and / or surrounding tissue. For example, the system may determine that the absorption coefficient value 415 decreases from the first instance (e.g., indicated by absorption coefficient value 415-a) to the second instance (e.g., indicated by the absorption coefficient value 415-b).

[0077] The second temperature curve 405-b may experience a peak at wavelength 410-a at the first absorption coefficient value 415-a. The first temperature curve 405-a may include the second absorption coefficient value 415-b, and the first temperature curve 405-a may be indicative of a water temperature that is less than the second temperature curve 405-b. In such cases, the system may determine that the temperature of the water decreases based on the coefficient value 415 decreasing from the first absorption coefficient value 415-a on the second temperature curve 405-b to the second absorption coefficient value 415-b on the first temperature curve 405-a.24Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0078] In some cases, the system (e.g., the wearable device, the one or more user devices, or a combination thereof) may verify the change in the absorption coefficient values 415, and therefore the change in the temperature of the water, by calculating the absorption coefficient values 415 for the second light having the second wavelength 410-b. For example, the system may determine, for the second light having the second wavelength 410-b, a third absorption coefficient value 415-c at the first instance based on the first absorption spectrum point and the second absorption spectrum point. The system may determine, for the second light having the second wavelength 410-b, a fourth absorption coefficient value 415-d value at the second instance based on the third absorption spectrum point and the fourth spectrum point, as described with reference to FIG. 1.

[0079] The system may determine, from the graphical representation 400, a difference between the third absorption coefficient value 415-c and the fourth absorption coefficient value 415-d for the second light having the second wavelength 410-b. The change in the absorption coefficient values 415 for the second light having the second wavelength 410-b may be indicative of a change in the temperature of the water and / or validate the change in temperature of the water based on the change in absorption coefficient values 415 for the first light having the first wavelength 410-a.

[0080] For example, the system may determine that the absorption coefficient value 415 increases from the first instance (e.g., indicated by third absorption coefficient value 415-c) to the second instance (e.g., indicated by the fourth absorption coefficient value 415-d). The first temperature curve 405-a may experience a peak at wavelength 410-b at the fourth absorption coefficient value 415-d. The fourth absorption coefficient value 415-d may be positioned on the first temperature curve 405-a. The first temperature curve 405-a may be indicative of a water temperature that is less than the third temperature curve 405-c. In such cases, the system may determine that the temperature of the water decreases based on the coefficient value 415 increasing from the third absorption coefficient value 415-c on the third temperature curve 405-c to the fourth absorption coefficient value 415-d on the first temperature curve 405-a.

[0081] The measured absorption coefficient value 415 at one wavelength (e.g., the first wavelength 410-a) at a first instance may be greater or smaller than the absorption 25Attorney Docket No. 048624.00994Oura271-l-WO-PCTcoefficient value 415 at a second instance depending on the water temperature. In such cases, the water temperature at the first instance may be greater or smaller than the water temperature at the second instance. The system may identify how the absorption coefficient values 415 change over time (e.g., decrease or increase), and based on the knowledge of how the absorption coefficient values 415 changes, the system may determine whether temperature of water changed (e.g., decreased or increased).

[0082] The system (e.g., the wearable device, the one or more user devices, or a combination thereof) may estimate the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user based on determining the change in temperature. The system calibrates an optical measurement signal (e.g., PPG-based signal or spectral fingerprint) or a non-optical measurement signal (e.g., ECG-based signal) using the measured blood temperature and / or the change in blood temperature in order to determine other health metrics (e.g., blood sugar, hemoglobin, fat content, metabolism, blood oxygen concentration, etc.) with increased accuracy and signal quality.

[0083] For example, the wearable device may perform a second measurement using one or more sensors of the plurality of sensors. The one or more sensors may be an example of a same light-emitting component, as described with reference to FIGs. 1 through 3, or may be a different sensor such as temperature sensor, a motion sensor, an ECG sensor, and the like. The second measurement may be performed before, after, or at the same time that the first measurement is performed. The second measurement may include a PPG measurement, a glucose measurement, a hemoglobin measurement, a fat content measurement, a metabolism measurement, a blood oxygen saturation measurement, or a combination thereof.

[0084] In one such example, blood oxygen saturation may be an example of an optical -based measurement that may be calibrated for better accuracy. If blood temperature is measured at light sources using light having a wavelength of equal to or greater than 1100 nm, then the temperature of blood may be used for selecting a predetermined blood oxygen saturation calibration curve that has been measured at that specific blood and / or tissue temperature.26Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0085] The system may calibrate the second measurement by adjusting the value of the second measurement to be within a threshold range based on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both. Calibrating the value of the second measurement may be an example of reducing or increasing the value of the second measurement to be within the threshold range based on the temperature of water decreasing or increasing from the first instance to the second instance. For example, the blood oxygen saturation may be 96%, but the system may determine that the temperature of the blood is increasing based on the techniques described herein. In such cases, the value of the blood oxygen saturation may be calibrated to be less than 96% based on the temperature of the blood increasing. The calibration may be based on applying a mathematical equation to the blood oxygen saturation to adjust a value of the blood oxygen saturation by a value, a ratio, a percentage, or a combination thereof. In some cases, near infrared spectroscopy (NIRS) measurements may be an example of the second measurement that is calibrated based on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both.

[0086] In other examples, the second measurement may be an example of a spectral measurement of blood lipids (e.g., fat). Blood lipids may include fewer absorption peaks in the short-wave infrared wavelengths as compared to water. If the water temperature may be measured with different spectral points than lipids, then the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both may be used to calibrate out the effect of water temperature changes during lipid spectral measurements.

[0087] In some cases, blood temperature changes may affect the lipid (e.g., fat content ) measurement without calibration. For example, by determining the blood temperature using the optical measurements, techniques described herein may allow for the ability to calibrate an optical measurement signal (e.g., PPG-based signal or spectral signature) using the measured blood temperature in order to determine fat content in the blood and / or surrounding tissues with increased accuracy and signal quality. Measuring fat content from blood may be sensitive to changes in absorption at or near a wavelength of 1200 nm (e.g., where an absorption coefficient of lipids is higher than an27Attorney Docket No. 048624.00994Oura271-l-WO-PCTabsorption coefficient of water). Measuring fat content from blood may be sensitive to changes in absorption at or near a wavelength of 900 to 1000 nm (e.g., where an absorption coefficient of lipids is lower than an absorption coefficient of water). In such cases, measuring a temperature of the blood and / or water using a wavelength at or near 900 to 1000 nm and at or near 1200 nm may improve the accuracy of measuring fat content by minimizing the effects of the temperature of the blood on lipid measurement.

[0088] In some cases, the system (e.g., the wearable device, the one or more user devices, or a combination thereof) may output a signal indicative of a calibrated version of the value of the second measurement. For example, the signal may be output to a user device associated with the wearable device and configured to cause a graphical user interface of the user device to display the calibrated version of the value of the second measurement. In some examples, the calibrated version of the value of the second measurement may be displayed to the user via the graphical user interface of the user device. For example, the message may indicate the calibrated version of the value of the second measurement without displaying the uncalibrated value of the second measurement. In such cases, the message may indicate that the value of the second measurement has been calibrated. In some cases, the signal may be configured to cause the graphical user interface of the user device to display a message associated with the calibrated version of the value of the second measurement. For example, the message may indicate “It looks like your body temperature is higher than normal. We’ve adjusted your blood oxygen saturation to account for the increase in body temperature.” In some cases, the message may indicate the blood and / or body temperature. The message may provide a more accurate estimation of body core temperature as related to blood temperature rather than presenting skin temperature. Displaying messages associated with the calibrated version of the value of the second measurement may provide some information or other insights regarding the calibrated version.Personalized insights may indicate aspects of collected physiological data (e.g., contributing factors within the physiological data) associated with the calibrated version.

[0089] FIG. 5 illustrates an example of a system 500 that supports light-based temperature calibration of physiological measurements in accordance with aspects of28Attorney Docket No. 048624.00994Oura271-l-WO-PCTthe present disclosure. The system 500 includes a plurality of electronic devices (e.g., wearable devices 504, user devices 506) that may be worn and / or operated by one or more users 502. The system 500 further includes a network 508 and one or more servers 510. The wearable devices 504 may be an example of the wearable devices as described with reference to FIGs. 1 through 3.

[0090] The electronic devices may include any electronic devices known in the art, including wearable devices 504 (e.g., ring wearable devices, watch wearable devices, etc.), user devices 506 (e.g., smartphones, laptops, tablets). The electronic devices associated with the respective users 502 may include one or more of the following functionalities: 1) measuring physiological data, 2) storing the measured data, 3) processing the data, 4) providing outputs (e.g., via GUIs) to a user 502 based on the processed data, and 5) communicating data with one another and / or other computing devices. Different electronic devices may perform one or more of the functionalities.

[0091] Example wearable devices 504 may include wearable computing devices, such as a ring computing device (hereinafter “ring”) configured to be worn on a user’s 502 finger, a wrist computing device (e.g., a smart watch, fitness band, or bracelet) configured to be worn on a user’s 502 wrist, and / or a head mounted computing device (e.g., glasses / goggles). Wearable devices 504 may also include bands, straps (e.g., flexible or inflexible bands or straps), stick-on sensors, and the like, that may be positioned in other locations, such as bands around the head (e.g., a forehead headband), arm (e.g., a forearm band and / or bicep band), and / or leg (e.g., a thigh or calf band), behind the ear, under the armpit, and the like. Wearable devices 504 may also be attached to, or included in, articles of clothing. For example, wearable devices 504 may be included in pockets and / or pouches on clothing. As another example, wearable device 504 may be clipped and / or pinned to clothing, or may otherwise be maintained within the vicinity of the user 502. Example articles of clothing may include, but are not limited to, hats, shirts, gloves, pants, socks, outerwear (e.g., jackets), and undergarments. In some implementations, wearable devices 504 may be included with other types of devices such as training / sporting devices that are used during physical activity. For example, wearable devices 504 may be attached to, or included in, a bicycle, skis, a tennis racket, a golf club, and / or training weights.29Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0092] Much of the present disclosure may be described in the context of a wearable device 504, which may include finger-worn wearable devices, wrist-worn wearable devices, and the like. Accordingly, the terms “wearable device 504,” “wearable ring device,” “ring,” and like terms, may be used interchangeably, unless noted otherwise herein. However, the use of the terms “wearable ring device” and / or “ring” are not to be regarded as limiting, as it is contemplated herein that aspects of the present disclosure may be performed using other wearable devices (e.g., watch wearable devices, necklace wearable device, bracelet wearable devices, earring wearable devices, anklet wearable devices, and the like).

[0093] In some aspects, user devices 506 may include handheld mobile computing devices, such as smartphones and tablet computing devices. User devices 506 may also include personal computers, such as laptop and desktop computing devices. Other example user devices 506 may include server computing devices that may communicate with other electronic devices (e.g., via the Internet). In some implementations, computing devices may include medical devices, such as external wearable computing devices (e.g., Holter monitors). Medical devices may also include implantable medical devices, such as pacemakers and cardioverter defibrillators. Other example user devices 506 may include home computing devices, such as internet of things (loT) devices (e.g., loT devices), smart televisions, smart speakers, smart displays (e.g., video call displays), hubs (e.g., wireless communication hubs), security systems, smart appliances (e.g., thermostats and refrigerators), and fitness equipment.

[0094] Some electronic devices (e.g., wearable devices 504, user devices 506) may measure physiological parameters of respective users 502, such as photoplethysmography waveforms, continuous skin temperature, a pulse waveform, respiration rate, heart rate, heart rate variability (HRV), actigraphy, galvanic skin response, pulse oximetry, blood oxygen saturation (SpO2), blood sugar levels (e.g., glucose metrics), and / or other physiological parameters. Some electronic devices that measure physiological parameters may also perform some / all of the calculations described herein. Some electronic devices may not measure physiological parameters, but may perform some / all of the calculations described herein. For example, a ring (e.g.,30Attorney Docket No. 048624.00994Oura271-l-WO-PCTwearable device 504), mobile device application, or a server computing device may process received physiological data that was measured by other devices.

[0095] In some implementations, a user 502 may operate, or may be associated with, multiple electronic devices, some of which may measure physiological parameters and some of which may process the measured physiological parameters. In some implementations, a user 502 may have a ring (e.g., wearable device 504) that measures physiological parameters. The user 502 may also have, or be associated with, a user device 506 (e.g., mobile device, smartphone), where the wearable device 504 and the user device 506 are communicatively coupled to one another. In some cases, the user device 506 may receive data from the wearable device 504 and perform some / all of the calculations described herein. In some implementations, the user device 506 may also measure physiological parameters described herein, such as motion / activity parameters.

[0096] For example, as illustrated in FIG. 5, a first user 502-a (User 1) may operate, or may be associated with, a wearable device 504-a (e.g., wearable ring device) and a user device 506-a that may operate as described herein. In this example, the user device 506-a associated with user 502-a may process / store physiological parameters measured by the wearable device 504-a. Comparatively, a second user 502-b (User 2) may be associated with wearable devices 504-b and 504-c (e.g., wearable ring device and a wrist-worn wearable device, such as a watch) and a user device 506-b, where the user device 506-b associated with user 502-b may process / store physiological parameters measured by the wearable devices 504-b and 504-c. Moreover, an nth user 502-n (User N) may be associated with an arrangement of electronic devices described herein (e.g., wearable device 504-n, user device 506-n). In some aspects, wearable devices 504 (e.g., wearable ring devices, wrist-worn wearable devices) and other electronic devices may be communicatively coupled to the user devices 506 of the respective users 502 via Bluetooth, Wi-Fi, and other wireless protocols. Moreover, in some cases, the wearable device 504 and the user device 506 may be included within (or make up) the same device. For example, in some cases, the wearable device 504 may be configured to execute an application associated with the wearable device 504, and may be configured to display data via a GUI.31Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0097] In some implementations, the wearable devices 504 (e.g., wearable ring devices) of the system 500 may be configured to collect physiological data from the respective users 502 based on arterial blood flow within the user’s finger. In particular, a wearable ring device may utilize one or more light-emitting components, such as LEDs (e.g., red LEDs, green LEDs) that emit light on the palm-side of a user’s finger to collect physiological data based on arterial blood flow within the user’s finger. In general, the terms light-emitting components, light-emitting elements, and like terms, may include, but are not limited to, LEDs, micro LEDs, mini LEDs, laser diodes (LDs) (e.g., vertical cavity surface-emitting lasers (VCSELs), and the like.

[0098] In some cases, the system 500 may be configured to collect physiological data from the respective users 502 based on blood flow diffused into a microvascular bed of skin with capillaries and arterioles. For example, the system 500 may collect PPG data based on a measured amount of blood diffused into the microvascular system of capillaries and arterioles. In some implementations, the wearable device 504 may acquire the physiological data using a combination of both green and red LEDs. The physiological data may include any physiological data known in the art including, but not limited to, temperature data, accelerometer data (e.g., movement / motion data), heart rate data, HRV data, blood oxygen level data, or any combination thereof.

[0099] The use of both green and red LEDs may provide several advantages over other solutions, as red and green LEDs have been found to have their own distinct advantages when acquiring physiological data under different conditions (e.g., light / dark, active / inactive) and via different parts of the body, and the like. For example, green LEDs have been found to exhibit better performance during exercise. Moreover, using multiple LEDs (e.g., green and red LEDs) distributed around the wearable device 504 (e.g., around an inner surface of the wearable ring device) has been found to exhibit superior performance as compared to wearable devices that utilize LEDs that are positioned close to one another, such as within a watch wearable device. Furthermore, the blood vessels in the finger (e.g., arteries, capillaries) are more accessible via LEDs as compared to blood vessels in the wrist. In particular, arteries in the wrist are positioned on the bottom of the wrist (e.g., palm-side of the wrist), meaning only capillaries are accessible on the top of the wrist (e.g., back of hand side of the wrist),32Attorney Docket No. 048624.00994Oura271-l-WO-PCTwhere wearable watch devices and similar devices are typically worn. As such, utilizing LEDs and other sensors within a wearable ring device has been found to exhibit superior performance as compared to wearable devices worn on the wrist, as the wearable ring device may have greater access to arteries (as compared to capillaries), thereby resulting in stronger signals and more valuable physiological data.

[0100] The electronic devices of the system 500 (e.g., user devices 506, wearable devices 504) may be communicatively coupled to one or more servers 510 via wired or wireless communication protocols. For example, as shown in FIG. 5, the electronic devices (e.g., user devices 506) may be communicatively coupled to one or more servers 510 via a network 508. The network 508 may implement transfer control protocol and internet protocol (TCP / IP), such as the Internet, or may implement other network 508 protocols. Network connections between the network 508 and the respective electronic devices may facilitate transport of data via email, web, text messages, mail, or any other appropriate form of interaction within a computer network 508. For example, in some implementations, the wearable device 504-a associated with the first user 502-a may be communicatively coupled to the user device 506-a, where the user device 506-a is communicatively coupled to the servers 510 via the network 508. In additional or alternative cases, wearable devices 504 (e.g., wearable ring devices, wrist-worn wearable devices such as watches) may be directly communicatively coupled to the network 508.

[0101] The system 500 may offer an on-demand database service between the user devices 506 and the one or more servers 510. In some cases, the servers 510 may receive data from the user devices 506 via the network 508, and may store and analyze the data. Similarly, the servers 510 may provide data to the user devices 506 via the network 508. In some cases, the servers 510 may be located at one or more data centers. The servers 510 may be used for data storage, management, and processing. In some implementations, the servers 510 may provide a web-based interface to the user device 106 via web browsers.

[0102] In some aspects, the system 500 may detect periods of time that a user 502 is asleep, and classify periods of time that the user 502 is asleep into one or more sleep stages (e.g., sleep stage classification). For example, as shown in FIG. 5, User 502-a 33Attorney Docket No. 048624.00994Oura271-l-WO-PCTmay be associated with a wearable device 504-a (e.g., wearable ring device) and a user device 506-a. In this example, the wearable device 504-a may collect physiological data associated with the user 502-a, including temperature, heart rate, HRV, respiratory rate, and the like. In some aspects, data collected by the wearable device 504-a may be input to a machine learning classifier, where the machine learning classifier is configured to determine periods of time that the user 502-a is (or was) asleep. Moreover, the machine learning classifier may be configured to classify periods of time into different sleep stages, including an awake sleep stage, a rapid eye movement (REM) sleep stage, a light sleep stage (non-REM (NREM)), and a deep sleep stage (NREM). In some aspects, the classified sleep stages may be displayed to the user 502-a via a GUI of the user device 506-a. Sleep stage classification may be used to provide feedback to a user 502-a regarding the user’s sleeping patterns, such as recommended bedtimes, recommended wake-up times, and the like. Moreover, in some implementations, sleep stage classification techniques described herein may be used to calculate scores for the respective user, such as Sleep Scores, Readiness Scores, and the like.

[0103] In some aspects, the system 500 may utilize circadian rhythm-derived features to further improve physiological data collection, data processing procedures, and other techniques described herein. The term circadian rhythm may refer to a natural, internal process that regulates an individual’s sleep-wake cycle, that repeats approximately every 24 hours. In this regard, techniques described herein may utilize circadian rhythm adjustment models to improve physiological data collection, analysis, and data processing. For example, a circadian rhythm adjustment model may be input into a machine learning classifier along with physiological data collected from the user 502-a via the wearable device 504-a. In this example, the circadian rhythm adjustment model may be configured to “weight,” or adjust, physiological data collected throughout a user’s natural, approximately 24-hour circadian rhythm. In some implementations, the system may initially start with a “baseline” circadian rhythm adjustment model, and may modify the baseline model using physiological data collected from each user 502 to generate tailored, individualized circadian rhythm adjustment models that are specific to each respective user 502.34Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0104] In some aspects, the system 500 may utilize other biological rhythms to further improve physiological data collection, analysis, and processing by phase of these other rhythms. For example, if a weekly rhythm is detected within an individual’s baseline data, then the model may be configured to adjust “weights” of data by day of the week. Biological rhythms that may require adjustment to the model by this method include: 1) ultradian (faster than a day rhythms, including sleep cycles in a sleep state, and oscillations from less than an hour to several hours periodicity in the measured physiological variables during wake state; 2) circadian rhythms; 3) non-endogenous daily rhythms shown to be imposed on top of circadian rhythms, as in work schedules; 4) weekly rhythms, or other artificial time periodicities exogenously imposed (e.g. in a hypothetical culture with 12 day “weeks,” 12 day rhythms could be used); 5) multi-day ovarian rhythms in women and spermatogenesis rhythms in men; 6) lunar rhythms (relevant for individuals living with low or no artificial lights); and 7) seasonal rhythms.

[0105] The biological rhythms are not always stationary rhythms. For example, many women experience variability in ovarian cycle length across cycles, and ultradian rhythms are not expected to occur at exactly the same time or periodicity across days even within a user. As such, signal processing techniques sufficient to quantify the frequency composition while preserving temporal resolution of these rhythms in physiological data may be used to improve detection of these rhythms, to assign phase of each rhythm to each moment in time measured, and to thereby modify adjustment models and comparisons of time intervals. The biological rhythm-adjustment models and parameters can be added in linear or non-linear combinations as appropriate to more accurately capture the dynamic physiological baselines of an individual or group of individuals.

[0106] In some aspects, the respective devices of the system 500 may support techniques for light-based temperature calibration of physiological measurements. The wearable device 504 may estimate the temperature of the user’s blood based on performing optical measurements. The wearable device 504 may calibrate the PPG signal or other measurements using the estimated temperature to determine one or more health metrics with higher accuracy.35Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0107] For example, the wearable device 504 may include a plurality of sensors configured to acquire physiological data from a user. The plurality of sensors may include one or more light-emitting components (e.g., VSCELs, LEDs, laser diodes, and the like) and one or more light-detecting components (e.g., photodetector, spectrometer, and the like), a battery configured to provide power to the plurality of sensors, electronic circuitry configured to electrically couple the battery with the plurality of sensors, and one or more processors communicatively coupled with the battery and the plurality of sensors. The one or more processors may be configured to perform a first measurement using the one or more light-emitting components having a wavelength at or above 1100 nanometers and estimate a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a finger (e.g., digit) of the user based on the first measurement. In some cases, the system 500 may perform a second measurement using one or more sensors of the plurality of sensors and calibrate a value of the second measurement using the temperature. In such cases, the system 500 may output a signal indicative of a calibrated version of the value of the second measurement based on using the estimated temperature of the water.

[0108] It should be appreciated by a person skilled in the art that one or more aspects of the disclosure may be implemented in a system 500 to additionally or alternatively solve other problems than those described above. Furthermore, aspects of the disclosure may provide technical improvements to “conventional” systems or processes as described herein. However, the description and appended drawings only include example technical improvements resulting from implementing aspects of the disclosure, and accordingly do not represent all of the technical improvements provided within the scope of the claims.

[0109] FIG. 6 illustrates an example of a system 600 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The system 600 may implement, or be implemented by, system 500. In particular, system 600 illustrates a wearable device 604 (e.g., wearable ring device), a user device 606, and a server 610, as described with reference to FIGs. 1 through 5.36Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0110] In some aspects, the wearable device 604 (e.g., wearable ring device) may be configured to be worn around a user’s finger, and may determine one or more user physiological parameters when worn around the user’s finger. Example measurements and determinations may include, but are not limited to, user skin temperature, pulse waveforms, respiratory rate, heart rate, HRV, blood oxygen levels (SpO2), blood sugar levels (e.g., glucose metrics), and the like.[OHl] The system 600 further includes a user device 606 (e.g., a smartphone) in communication with the wearable device 604. For example, the wearable device 604 may be in wireless and / or wired communication with the user device 606. In some implementations, the wearable device 604 may send measured and processed data (e.g., temperature data, PPG data, motion / accelerometer data, ring input data, and the like) to the user device 606. The user device 606 may also send data to the wearable device 604, such as firmware / configuration updates. The user device 606 may process data. In some implementations, the user device 606 may transmit data to the server 610 for processing and / or storage.

[0112] The wearable device 604 may include a housing 605 that may include an inner housing 605-a and an outer housing 605-b. In some aspects, the inner housing 605-a, the outer housing 605-b, or both, may include a curved profile / surface. In particular, the housing 605 may exhibit any curved or “circumferential” profile, including a circular profile, an elliptical profile, and the like. Moreover, in some cases, the inner housing 605-a, the outer housing 605-b, or both, may include both curved (e.g., “circumferential”) and flat / planar portions. For the purposes of the present disclosure, the term “circumferential” may be used interchangeably with the term “curved” to refer to circular-shaped, elliptical-shaped, or other curved-shaped profile.

[0113] In some aspects, the housing 605 of the wearable device 604 may store or otherwise include various components of the ring including, but not limited to, device electronics, a power source (e.g., battery 611, and / or capacitor), one or more substrates (e.g., printable circuit boards) that interconnect the device electronics and / or power source, and the like. The device electronics may include device modules (e.g., hardware / software), such as: a processing module 630-a, a memory 615, a communication module 620-a, a power module 625, and the like. The device electronics 37Attorney Docket No. 048624.00994Oura271-l-WO-PCTmay also include one or more sensors. Example sensors may include one or more temperature sensors 640, a PPG sensor assembly (e.g., PPG system 635), and one or more motion sensors 645.

[0114] The sensors may include associated modules (not illustrated) configured to communicate with the respective components / modules of the wearable device 604, and generate signals associated with the respective sensors. In some aspects, each of the components / modules of the wearable device 604 may be communicatively coupled to one another via wired or wireless connections. Moreover, the wearable device 604 may include additional and / or alternative sensors or other components that are configured to collect physiological data from the user, including light sensors (e.g., LEDs), oximeters, and the like.

[0115] The wearable device 604 shown and described with reference to FIG. 6 is provided solely for illustrative purposes. As such, the wearable device 604 may include additional or alternative components as those illustrated in FIG. 6. Additional or alternative wearable devices 604 that provide functionality described herein may be fabricated. For example, wearable devices 604 with fewer components (e.g., sensors) may be fabricated. In a specific example, a wearable device 604 with a single temperature sensor 640 (or other sensor), a power source, and device electronics configured to read the single temperature sensor 640 (or other sensor) may be fabricated. In another specific example, a temperature sensor 640 (or other sensor) may be attached to a user’s finger (e.g., using adhesives, wraps, clamps, spring loaded clamps, etc.). In this case, the sensor may be wired to another computing device, such as a wrist worn computing device that reads the temperature sensor 640 (or other sensor). In other examples, a wearable device 604 that includes additional sensors and processing functionality may be fabricated.

[0116] The housing 605 may include one or more housing components. The housing 605 may include an outer housing 605-b component (e.g., a shell) and an inner housing 605-a component (e.g., a molding). The housing 605 may include additional components (e.g., additional layers) not explicitly illustrated in FIG. 6. For example, in some implementations, the wearable device 604 may include one or more insulating layers that electrically insulate the device electronics and other conductive materials 38Attorney Docket No. 048624.00994Oura271-l-WO-PCT(e.g., electrical traces) from the outer housing 605-b. The housing 605 may provide structural support for the device electronics, battery 611, substrate(s), and other components. For example, the housing 605 may protect the device electronics, battery 611, and substrate(s) from mechanical forces, such as pressure and impacts. The housing 605 may also protect the device electronics, battery 611, and substrate(s) from water and / or other chemicals.

[0117] The inner housing 605-a may be configured to interface with the user’s finger. The inner housing 605-a may be formed from a polymer (e.g., a medical grade polymer) or other material. In some implementations, the inner housing 605-a may be transparent. For example, the inner housing 605-a may be transparent to light emitted by the PPG LEDs. In some implementations, the inner housing 605-a component may be molded onto the outer housing 605-b. For example, the inner housing 605-a may include a polymer that is molded (e.g., injection molded) to fit into an outer housing 605-b metallic shell.

[0118] The inner housing 605-a and the outer housing 605-b may be fabricated from one or more materials. In some implementations, the inner housing 605-a, the outer housing 605-b, or both, may include a metal, such as titanium, that may provide strength and abrasion resistance at a relatively light weight. Additionally, or alternatively, the inner housing 605-a, and / or the outer housing 605-b may also be fabricated from other materials, such polymers, plastic materials, epoxy materials, ceramic materials, and the like. In some implementations, the outer housing 605-b may be protective as well as decorative.

[0119] The wearable device 604 may include one or more substrates (not illustrated). The device electronics and battery 611 may be included on the one or more substrates. For example, the device electronics and battery 611 may be mounted on one or more substrates. Example substrates may include one or more printed circuit boards (PCBs), such as flexible PCB (e.g., polyimide). In some implementations, the electronics / battery 611 may include surface mounted devices (e.g., surface-mount technology (SMT) devices) on a flexible PCB. In some implementations, the one or more substrates (e.g., one or more flexible PCBs) may include electrical traces that39Attorney Docket No. 048624.00994Oura271-l-WO-PCTprovide electrical communication between device electronics. The electrical traces may also connect the battery 611 to the device electronics.

[0120] The device electronics, battery 611, and substrates may be arranged in the wearable device 604 in a variety of ways. In some implementations, one substrate that includes device electronics may be mounted along the bottom of the wearable device 604 (e.g., the bottom half), such that the sensors (e.g., PPG system 635, temperature sensors 640, motion sensors 645, and other sensors) interface with the underside of the user’s finger. In these implementations, the battery 611 may be included along the top portion of the wearable device 604 (e.g., on another substrate).

[0121] The various components / modules of the wearable device 604 represent functionality (e.g., circuits and other components) that may be included in the wearable device 604. Modules may include any discrete and / or integrated electronic circuit components that implement analog and / or digital circuits capable of producing the functions attributed to the modules herein. For example, the modules may include analog circuits (e.g., amplification circuits, filtering circuits, analog / digital conversion circuits, and / or other signal conditioning circuits). The modules may also include digital circuits (e.g., combinational or sequential logic circuits, memory circuits etc.).

[0122] The memory 615 (memory module) of the wearable device 604 may include any volatile, non-volatile, magnetic, or electrical media, such as a random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically-erasable programmable ROM (EEPROM), flash memory, or any other memory device. The memory 615 may store any of the data described herein. For example, the memory 615 may be configured to store data (e.g., motion data, temperature data, PPG data) collected by the respective sensors and PPG system 635. Furthermore, memory 615 may include instructions that, when executed by one or more processing circuits, cause the modules to perform various functions attributed to the modules herein. The device electronics of the wearable device 604 described herein are only example device electronics. As such, the types of electronic components used to implement the device electronics may vary based on design considerations.40Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0123] The functions attributed to the modules of the wearable device 604 (e.g., wearable ring device) described herein may be embodied as one or more processors, hardware, firmware, software, or any combination thereof. Depiction of different features as modules is intended to highlight different functional aspects and does not necessarily imply that such modules must be realized by separate hardware / software components. Rather, functionality associated with one or more modules may be performed by separate hardware / software components or integrated within common hardware / software components.

[0124] The processing module 630-a of the wearable device 604 may include one or more processors (e.g., processing units), microcontrollers, digital signal processors, systems on a chip (SOCs), and / or other processing devices. The processing module 630-a communicates with the modules included in the wearable device 604. For example, the processing module 630-a may transmit / receive data to / from the modules and other components of the wearable device 604, such as the sensors. As described herein, the modules may be implemented by various circuit components. Accordingly, the modules may also be referred to as circuits (e.g., a communication circuit and power circuit).

[0125] The processing module 630-a may communicate with the memory 615. The memory 615 may include computer-readable instructions that, when executed by the processing module 630-a, cause the processing module 630-a to perform the various functions attributed to the processing module 630-a herein. In some implementations, the processing module 630-a (e.g., a microcontroller) may include additional features associated with other modules, such as communication functionality provided by the communication module 620-a (e.g., an integrated Bluetooth Low Energy transceiver) and / or additional onboard memory 615.

[0126] The communication module 620-a may include circuits that provide wireless and / or wired communication with the user device 606 (e.g., communication module 620-b of the user device 606). In some implementations, the communication modules 620-a, 620-b may include wireless communication circuits, such as Bluetooth circuits and / or Wi-Fi circuits. In some implementations, the communication modules 620-a, 620-b can include wired communication circuits, such as Universal Serial Bus (USB)41Attorney Docket No. 048624.00994Oura271-l-WO-PCTcommunication circuits. Using the communication module 620-a, the wearable device 604 and the user device 606 may be configured to communicate with each other. The processing module 630-a of the ring may be configured to transmit / receive data to / from the user device 606 via the communication module 620-a. Example data may include, but is not limited to, motion data, temperature data, pulse waveforms, heart rate data, HRV data, PPG data, and status updates (e.g., charging status, battery charge level, and / or wearable device 604 configuration settings). The processing module 630-a of the ring may also be configured to receive updates (e.g., software / firmware updates) and data from the user device 606.

[0127] The wearable device 604 may include a battery 611 (e.g., a rechargeable battery 611). An example battery 611 may include a Lithium-Ion or Lithium-Polymer type battery 611, although a variety of battery 611 options are possible. The battery 611 may be wirelessly charged. In some implementations, the wearable device 604 may include a power source other than the battery 611, such as a capacitor. The power source (e.g., battery 611 or capacitor) may have a curved geometry that matches the curve of the wearable device 604. In some aspects, a charger or other power source may include additional sensors that may be used to collect data in addition to, or that supplements, data collected by the wearable device 604 itself. Moreover, a charger or other power source for the wearable device 604 may function as a user device 606, in which case the charger or other power source for the wearable device 604 may be configured to receive data from the wearable device 604, store and / or process data received from the wearable device 604, and communicate data between the wearable device 604 and the servers 610.

[0128] In some aspects, the wearable device 604 includes a power module 625 that may control charging of the battery 611. For example, the power module 625 may interface with an external wireless charger that charges the battery 611 when interfaced with the wearable device 604. The charger may include a datum structure that mates with a wearable device 604 datum structure to create a specified orientation with the wearable device 604 during charging. The power module 625 may also regulate voltage(s) of the device electronics, regulate power output to the device electronics, and monitor the state of charge of the battery 611. In some implementations, the battery 61142Attorney Docket No. 048624.00994Oura271-l-WO-PCTmay include a protection circuit module (PCM) that protects the battery 611 from high current discharge, over voltage during charging, and under voltage during discharge. The power module 625 may also include electro-static discharge (ESD) protection.

[0129] The one or more temperature sensors 640 may be electrically coupled to the processing module 630-a. The temperature sensor 640 may be configured to generate a temperature signal (e.g., temperature data) that indicates a temperature read or sensed by the temperature sensor 640. The processing module 630-a may determine a temperature of the user in the location of the temperature sensor 640. For example, in the wearable device 604, temperature data generated by the temperature sensor 640 may indicate a temperature of a user at the user’s finger (e.g., skin temperature). In some implementations, the temperature sensor 640 may contact the user’s skin. In other implementations, a portion of the housing 605 (e.g., the inner housing 605-a) may form a barrier (e.g., a thin, thermally conductive barrier) between the temperature sensor 640 and the user’s skin. In some implementations, portions of the wearable device 604 configured to contact the user’s finger may have thermally conductive portions and thermally insulative portions. The thermally conductive portions may conduct heat from the user’s finger to the temperature sensors 640. The thermally insulative portions may insulate portions of the wearable device 604 (e.g., the temperature sensor 640) from ambient temperature.

[0130] In some implementations, the temperature sensor 640 may generate a digital signal (e.g., temperature data) that the processing module 630-a may use to determine the temperature. As another example, in cases where the temperature sensor 640 includes a passive sensor, the processing module 630-a (or a temperature sensor 640 module) may measure a current / voltage generated by the temperature sensor 640 and determine the temperature based on the measured current / voltage. Example temperature sensors 640 may include a thermistor, such as a negative temperature coefficient (NTC) thermistor, or other types of sensors including resistors, transistors, diodes, and / or other el ectri cal / electron! c components .

[0131] The processing module 630-a may sample the user’s temperature over time. For example, the processing module 630-a may sample the user’s temperature according to a sampling rate. An example sampling rate may include one sample per second,43Attorney Docket No. 048624.00994Oura271-l-WO-PCTalthough the processing module 630-a may be configured to sample the temperature signal at other sampling rates that are higher or lower than one sample per second. In some implementations, the processing module 630-a may sample the user’s temperature continuously throughout the day and night. Sampling at a sufficient rate (e.g., one sample per second) throughout the day may provide sufficient temperature data for analysis described herein.

[0132] The processing module 630-a may store the sampled temperature data in memory 615. In some implementations, the processing module 630-a may process the sampled temperature data. For example, the processing module 630-a may determine average temperature values over a period of time. In one example, the processing module 630-a may determine an average temperature value each minute by summing all temperature values collected over the minute and dividing by the number of samples over the minute. In a specific example where the temperature is sampled at one sample per second, the average temperature may be a sum of all sampled temperatures for one minute divided by sixty seconds. The memory 615 may store the average temperature values over time. In some implementations, the memory 615 may store average temperatures (e.g., one per minute) instead of sampled temperatures in order to conserve memory 615.

[0133] The sampling rate, which may be stored in memory 615, may be configurable. In some implementations, the sampling rate may be the same throughout the day and night. In other implementations, the sampling rate may be changed throughout the day / night. In some implementations, the wearable device 604 may filter / reject temperature readings, such as large spikes in temperature that are not indicative of physiological changes (e.g., a temperature spike from a hot shower). In some implementations, the wearable device 604 may filter / reject temperature readings that may not be reliable due to other factors, such as excessive motion during exercise (e.g., as indicated by a motion sensor 645).

[0134] The wearable device 604 (e.g., communication module) may transmit the sampled and / or average temperature data to the user device 606 for storage and / or further processing. The user device 606 may transfer the sampled and / or average temperature data to the server 610 for storage and / or further processing.44Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0135] Although the wearable device 604 is illustrated as including a single temperature sensor 640, the wearable device 604 may include multiple temperature sensors 640 in one or more locations, such as arranged along the inner housing 605-a near the user’s finger. In some implementations, the temperature sensors 640 may be stand-alone temperature sensors 640. Additionally, or alternatively, one or more temperature sensors 640 may be included with other components (e.g., packaged with other components), such as with the accelerometer and / or processor.

[0136] The processing module 630-a may acquire and process data from multiple temperature sensors 640 in a similar manner described with respect to a single temperature sensor 640. For example, the processing module 630 may individually sample, average, and store temperature data from each of the multiple temperature sensors 640. In other examples, the processing module 630-a may sample the sensors at different rates and average / store different values for the different sensors. In some implementations, the processing module 630-a may be configured to determine a single temperature based on the average of two or more temperatures determined by two or more temperature sensors 640 in different locations on the finger.

[0137] The temperature sensors 640 on the wearable device 604 (e.g., wearable ring device) may acquire distal temperatures at the user’s finger (e.g., any finger). For example, one or more temperature sensors 640 on the wearable device 604 may acquire a user’s temperature from the underside of a finger or at a different location on the finger. In some implementations, the wearable device 604 may continuously acquire distal temperature (e.g., at a sampling rate). Although distal temperature measured by a wearable device 604 at the finger is described herein, other devices may measure temperature at the same / diff erent locations. In some cases, the distal temperature measured at a user’s finger may differ from the temperature measured at a user’s wrist or other external body location. Additionally, the distal temperature measured at a user’s finger (e.g., a “shell” temperature) may differ from the user’s core temperature. As such, the wearable device 604 may provide a useful temperature signal that may not be acquired at other internal / extemal locations of the body. In some cases, continuous temperature measurement at the finger may capture temperature fluctuations (e.g., small or large fluctuations) that may not be evident in core temperature. For example,45Attorney Docket No. 048624.00994Oura271-l-WO-PCTcontinuous temperature measurement at the finger may capture minute-to-minute or hour-to-hour temperature fluctuations that provide additional insight that may not be provided by other temperature measurements elsewhere in the body.

[0138] The wearable device 604 may include a PPG system 635. The PPG system 635 may include one or more optical transmitters that transmit light. The PPG system 635 may also include one or more optical receivers that receive light transmitted by the one or more optical transmitters. An optical receiver may generate a signal (hereinafter “PPG” signal) that indicates an amount of light received by the optical receiver. The optical transmitters may illuminate a region of the user’s finger. The PPG signal generated by the PPG system 635 may indicate the perfusion of blood in the illuminated region. For example, the PPG signal may indicate blood volume changes in the illuminated region caused by a user’s pulse pressure. The processing module 630-a may sample the PPG signal and determine a user’s pulse waveform based on the PPG signal. The processing module 630-a may determine a variety of physiological parameters based on the user’s pulse waveform, such as a user’s respiratory rate, heart rate, HRV, oxygen saturation, and other circulatory parameters.

[0139] In some implementations, the PPG system 635 may be configured as a reflective PPG system 635 where the optical receiver(s) receive transmitted light that is reflected through the region of the user’s finger. In some implementations, the PPG system 635 may be configured as a transmissive PPG system 635 where the optical transmitter(s) and optical receiver(s) are arranged opposite to one another, such that light is transmitted directly through a portion of the user’s finger to the optical receiver(s).

[0140] The number and ratio of transmitters and receivers included in the PPG system 635 may vary. Example optical transmitters may include LEDs. The optical transmitters may transmit light in the infrared spectrum and / or other spectrums.Example optical receivers may include, but are not limited to, photosensors, phototransistors, and photodiodes. The optical receivers may be configured to generate PPG signals in response to the wavelengths received from the optical transmitters. The location of the transmitters and receivers may vary. Additionally, a single device may include reflective and / or transmissive PPG systems 635.46Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0141] The PPG system 635 illustrated in FIG. 6 may include a reflective PPG system 635 in some implementations. In these implementations, the PPG system 635 may include a centrally located optical receiver (e.g., at the bottom of the wearable device 604) and two optical transmitters located on each side of the optical receiver. In this implementation, the PPG system 635 (e.g., optical receiver) may generate the PPG signal based on light received from one or both of the optical transmitters. In other implementations, other placements, combinations, and / or configurations of one or more optical transmitters and / or optical receivers are contemplated.

[0142] The processing module 630-a may control one or both of the optical transmitters to transmit light while sampling the PPG signal generated by the optical receiver. In some implementations, the processing module 630-a may cause the optical transmitter with the stronger received signal to transmit light while sampling the PPG signal generated by the optical receiver. For example, the selected optical transmitter may continuously emit light while the PPG signal is sampled at a sampling rate (e.g., 250 Hz).

[0143] Sampling the PPG signal generated by the PPG system 635 may result in a pulse waveform that may be referred to as a “PPG.” The pulse waveform may indicate blood pressure vs time for multiple cardiac cycles. The pulse waveform may include peaks that indicate cardiac cycles. Additionally, the pulse waveform may include respiratory induced variations that may be used to determine respiration rate. The processing module 630-a may store the pulse waveform in memory 615 in some implementations. The processing module 630-a may process the pulse waveform as it is generated and / or from memory 615 to determine user physiological parameters described herein.

[0144] The processing module 630-a may determine the user’s heart rate based on the pulse waveform. For example, the processing module 630-a may determine heart rate (e.g., in beats per minute) based on the time between peaks in the pulse waveform. The time between peaks may be referred to as an interbeat interval (IB I). The processing module 630-a may store the determined heart rate values and IBI values in memory 615.47Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0145] The processing module 630-a may determine HRV over time. For example, the processing module 630-a may determine HRV based on the variation in the IBIs. The processing module 630-a may store the HRV values over time in the memory 615. Moreover, the processing module 630-a may determine the user’s respiratory rate over time. For example, the processing module 630-a may determine respiratory rate based on frequency modulation, amplitude modulation, or baseline modulation of the user’s IBI values over a period of time. Respiratory rate may be calculated in breaths per minute or as another breathing rate (e.g., breaths per 30 seconds). The processing module 630-a may store user respiratory rate values over time in the memory 615.

[0146] The wearable device 604 may include one or more motion sensors 645, such as one or more accelerometers (e.g., 6-D accelerometers) and / or one or more gyroscopes (gyros). The motion sensors 645 may generate motion signals that indicate motion of the sensors. For example, the wearable device 604 may include one or more accelerometers that generate acceleration signals that indicate acceleration of the accelerometers. As another example, the wearable device 604 may include one or more gyro sensors that generate gyro signals that indicate angular motion (e.g., angular velocity) and / or changes in orientation. The motion sensors 645 may be included in one or more sensor packages. An example accelerometer / gyro sensor is a Bosch BMI160 inertial micro electro-mechanical system (MEMS) sensor that may measure angular rates and accelerations in three perpendicular axes.

[0147] The processing module 630-a may sample the motion signals at a sampling rate (e.g., 50Hz) and determine the motion of the wearable device 604 based on the sampled motion signals. For example, the processing module 630-a may sample acceleration signals to determine acceleration of the wearable device 604. As another example, the processing module 630-a may sample a gyro signal to determine angular motion. In some implementations, the processing module 630-a may store motion data in memory 615. Motion data may include sampled motion data as well as motion data that is calculated based on the sampled motion signals (e.g., acceleration and angular values).

[0148] The wearable device 604 may store a variety of data described herein. For example, the wearable device 604 may store temperature data, such as raw sampled 48Attorney Docket No. 048624.00994Oura271-l-WO-PCTtemperature data and calculated temperature data (e.g., average temperatures). As another example, wearable device 604 may store PPG signal data, such as pulse waveforms and data calculated based on the pulse waveforms (e.g., heart rate values, IBI values, HRV values, and respiratory rate values). The wearable device 604 may also store motion data, such as sampled motion data that indicates linear and angular motion.

[0149] The wearable device 604, or other computing device, may calculate and store additional values based on the sampled / calculated physiological data. For example, the processing module 630 may calculate and store various metrics, such as sleep metrics (e.g., a Sleep Score), activity metrics, and readiness metrics. In some implementations, additional values / metrics may be referred to as “derived values.” The wearable device 604, or other computing / wearable device, may calculate a variety of values / metrics with respect to motion. Example derived values for motion data may include, but are not limited to, motion count values, regularity values, intensity values, metabolic equivalence of task values (METs), and orientation values. Motion counts, regularity values, intensity values, and METs may indicate an amount of user motion (e.g., velocity / acceleration) over time. Orientation values may indicate how the wearable device 604 is oriented on the user’s finger and if the wearable device 604 is worn on the left hand or right hand.

[0150] In some implementations, motion counts and regularity values may be determined by counting a number of acceleration peaks within one or more periods of time (e.g., one or more 30 second to 1 minute periods). Intensity values may indicate a number of movements and the associated intensity (e.g., acceleration values) of the movements. The intensity values may be categorized as low, medium, and high, depending on associated threshold acceleration values. METs may be determined based on the intensity of movements during a period of time (e.g., 30 seconds), the regularity / irregularity of the movements, and the number of movements associated with the different intensities.

[0151] In some implementations, the processing module 630-a may compress the data stored in memory 615. For example, the processing module 630-a may delete sampled data after making calculations based on the sampled data. As another example, the processing module 630-a may average data over longer periods of time in order to 49Attorney Docket No. 048624.00994Oura271-l-WO-PCTreduce the number of stored values. In a specific example, if average temperatures for a user over one minute are stored in memory 615, the processing module 630-a may calculate average temperatures over a five minute time period for storage, and then subsequently erase the one minute average temperature data. The processing module 630-a may compress data based on a variety of factors, such as the total amount of used / available memory 615 and / or an elapsed time since the wearable device 604 last transmitted the data to the user device 606.

[0152] Although a user’s physiological parameters may be measured by sensors included on a wearable device 604, other devices may measure a user’s physiological parameters. For example, although a user’s temperature may be measured by a temperature sensor 640 included in a wearable device 604, other devices may measure a user’s temperature. In some examples, other wearable devices (e.g., wrist devices) may include sensors that measure user physiological parameters. Additionally, medical devices, such as external medical devices (e.g., wearable medical devices) and / or implantable medical devices, may measure a user’s physiological parameters. One or more sensors on any type of computing device may be used to implement the techniques described herein.

[0153] The physiological measurements may be taken continuously throughout the day and / or night. In some implementations, the physiological measurements may be taken during portions of the day and / or portions of the night. In some implementations, the physiological measurements may be taken in response to determining that the user is in a specific state, such as an active state, resting state, and / or a sleeping state. For example, the wearable device 604 can make physiological measurements in a resting / sleep state in order to acquire cleaner physiological signals. In one example, the wearable device 604 or other device / system may detect when a user is resting and / or sleeping and acquire physiological parameters (e.g., temperature) for that detected state. The devices / systems may use the resting / sleep physiological data and / or other data when the user is in other states in order to implement the techniques of the present disclosure.

[0154] In some implementations, as described previously herein, the wearable device 604 may be configured to collect, store, and / or process data, and may transfer 50Attorney Docket No. 048624.00994Oura271-l-WO-PCTany of the data described herein to the user device 606 for storage and / or processing. In some aspects, the user device 606 includes a wearable application 650, an operating system 685 (OS), a web browser application (e.g., web browser 680), one or more additional applications, and a GUI 675. The user device 606 may further include other modules and components, including sensors, audio devices, haptic feedback devices, and the like. The wearable application 650 may include an example of an application (e.g., “app”) that may be installed on the user device 606. The wearable application 650 may be configured to acquire data from the wearable device 604, store the acquired data, and process the acquired data as described herein. For example, the wearable application 650 may include a user interface (UI) module 655, an acquisition module 660, a processing module 630-b, a communication module 620-b, and a storage module (e.g., database 665) configured to store application data.

[0155] In some cases, the wearable device 604 and the user device 606 may be included within (or make up) the same device. For example, in some cases, the wearable device 604 may be configured to execute the wearable application 650, and may be configured to display data via the GUI 675.

[0156] The various data processing operations described herein may be performed by the wearable device 604, the user device 606, the servers 610, or any combination thereof. For example, in some cases, data collected by the wearable device 604 may be pre-processed and transmitted to the user device 606. In this example, the user device 606 may perform some data processing operations on the received data, may transmit the data to the servers 610 for data processing, or both. For instance, in some cases, the user device 606 may perform processing operations that require relatively low processing power and / or operations that require a relatively low latency, whereas the user device 606 may transmit the data to the servers 610 for processing operations that require relatively high processing power and / or operations that may allow relatively higher latency.

[0157] In some aspects, the wearable device 604 (e.g., wearable ring device), user device 606, and server 610 of the system 600 may be configured to evaluate sleep patterns for a user. In particular, the respective components of the system 600 may be used to collect data from a user via the wearable device 604, and generate one or more 51Attorney Docket No. 048624.00994Oura271-l-WO-PCTscores (e.g., Sleep Score, Readiness Score) for the user based on the collected data. For example, as noted previously herein, the wearable device 604 of the system 600 may be worn by a user to collect data from the user, including temperature, heart rate, HRV, and the like. Data collected by the wearable device 604 may be used to determine when the user is asleep in order to evaluate the user’s sleep for a given “sleep day.” In some aspects, scores may be calculated for the user for each respective sleep day, such that a first sleep day is associated with a first set of scores, and a second sleep day is associated with a second set of scores. Scores may be calculated for each respective sleep day based on data collected by the wearable device 604 during the respective sleep day. Scores may include, but are not limited to, Sleep Scores, Readiness Scores, and the like.

[0158] In some cases, “sleep days” may align with the traditional calendar days, such that a given sleep day runs from midnight to midnight of the respective calendar day. In other cases, sleep days may be offset relative to calendar days. For example, sleep days may run from 6:00 pm (18:00) of a calendar day until 6:00 pm (18:00) of the subsequent calendar day. In this example, 6:00 pm may serve as a “cut-off time,” where data collected from the user before 6:00 pm is counted for the current sleep day, and data collected from the user after 6:00 pm is counted for the subsequent sleep day. Due to the fact that most individuals sleep the most at night, offsetting sleep days relative to calendar days may enable the system 600 to evaluate sleep patterns for users in such a manner that is consistent with their sleep schedules. In some cases, users may be able to selectively adjust (e.g., via the GUI) a timing of sleep days relative to calendar days so that the sleep days are aligned with the duration of time that the respective users typically sleep.

[0159] In some implementations, each overall score for a user for each respective day (e.g., Sleep Score, Readiness Score) may be determined / calculated based on one or more “contributors,” “factors,” or “contributing factors.” For example, a user’s overall Sleep Score may be calculated based on a set of contributors, including: total sleep, efficiency, restfulness, REM sleep, deep sleep, latency, timing, or any combination thereof. The Sleep Score may include any quantity of contributors. The “total sleep” contributor may refer to the sum of all sleep periods of the sleep day. The “efficiency”52Attorney Docket No. 048624.00994Oura271-l-WO-PCTcontributor may reflect the percentage of time spent asleep compared to time spent awake while in bed, and may be calculated using the efficiency average of long sleep periods (e.g., primary sleep period) of the sleep day, weighted by a duration of each sleep period. The “restfulness” contributor may indicate how restful the user’s sleep is, and may be calculated using the average of all sleep periods of the sleep day, weighted by a duration of each period. The restfulness contributor may be based on a “wake up count” (e.g., sum of all the wake-ups (when user wakes up) detected during different sleep periods), excessive movement, and a “got up count” (e.g., sum of all the got-ups (when user gets out of bed) detected during the different sleep periods).

[0160] The “REM sleep” contributor may refer to a sum total of REM sleep durations across all sleep periods of the sleep day including REM sleep. Similarly, the “deep sleep” contributor may refer to a sum total of deep sleep durations across all sleep periods of the sleep day including deep sleep. The “latency” contributor may signify how long (e.g., average, median, longest) the user takes to go to sleep, and may be calculated using the average of long sleep periods throughout the sleep day, weighted by a duration of each period and the number of such periods (e.g., consolidation of a given sleep stage or sleep stages may be its own contributor or weight other contributors). Lastly, the “timing” contributor may refer to a relative timing of sleep periods within the sleep day and / or calendar day, and may be calculated using the average of all sleep periods of the sleep day, weighted by a duration of each period.

[0161] By way of another example, a user’s overall Readiness Score may be calculated based on a set of contributors, including: sleep, sleep balance, heart rate, HRV balance, recovery index, temperature, activity, activity balance, or any combination thereof. The Readiness Score may include any quantity of contributors. The “sleep” contributor may refer to the combined Sleep Score of all sleep periods within the sleep day. The “sleep balance” contributor may refer to a cumulative duration of all sleep periods within the sleep day. In particular, sleep balance may indicate to a user whether the sleep that the user has been getting over some duration of time (e.g., the past two weeks) is in balance with the user’s needs. Typically, adults need 7-9 hours of sleep a night to stay healthy, alert, and to perform at their best both mentally and physically. However, it is normal to have an occasional night of bad sleep, so the sleep53Attorney Docket No. 048624.00994Oura271-l-WO-PCTbalance contributor takes into account long-term sleep patterns to determine whether each user’s sleep needs are being met. The “resting heart rate” contributor may indicate a lowest heart rate from the longest sleep period of the sleep day (e.g., primary sleep period) and / or the lowest heart rate from naps occurring after the primary sleep period.

[0162] Continuing with reference to the “contributors” (e.g., factors, contributing factors) of the Readiness Score, the “HRV balance” contributor may indicate a highest HRV average from the primary sleep period and the naps happening after the primary sleep period. The HRV balance contributor may help users keep track of their recovery status by comparing their HRV trend over a first time period (e.g., two weeks) to an average HRV over some second, longer time period (e.g., three months). The “recovery index” contributor may be calculated based on the longest sleep period. Recovery index measures how long it takes for a user’s resting heart rate to stabilize during the night. A sign of a very good recovery is that the user’s resting heart rate stabilizes during the first half of the night, at least six hours before the user wakes up, leaving the body time to recover for the next day. The “body temperature” contributor may be calculated based on the longest sleep period (e.g., primary sleep period) or based on a nap happening after the longest sleep period if the user’s highest temperature during the nap is at least 0.5°C higher than the highest temperature during the longest period. In some aspects, the ring may measure a user’s body temperature while the user is asleep, and the system 600 may display the user’s average temperature relative to the user’s baseline temperature. If a user’s body temperature is outside of their normal range (e.g., clearly above or below 0.0), the body temperature contributor may be highlighted (e.g., go to a “Pay attention” state) or otherwise generate an alert for the user.

[0163] FIG. 7 shows a block diagram 700 of a device 705 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The device 705 may include an input module 710, an output module 715, and a wearable device manager 720. The device 705, or one of more components of the device 705 (e.g., the input module 710, the output module 715, the wearable device manager 720), may include at least one processor, which may be coupled with at least one memory, to support the described techniques. Each of these components may be in communication with one another (e.g., via one or more buses).54Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0164] For example, the wearable device manager 720 may include a first measurement component 725, a temperature component 730, a second measurement component 735, a calibration component 740, a signal component 745, or any combination thereof. In some examples, the wearable device manager 720, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the input module 710, the output module 715, or both. For example, the wearable device manager 720 may receive information from the input module 710, send information to the output module 715, or be integrated in combination with the input module 710, the output module 715, or both to receive information, transmit information, or perform various other operations as described herein.

[0165] The first measurement component 725 may be configured as or otherwise support a means for performing a first measurement using the one or more lightemitting components having a wavelength at or above 1100 nanometers. The temperature component 730 may be configured as or otherwise support a means for estimating a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement. The second measurement component 735 may be configured as or otherwise support a means for performing a second measurement using one or more sensors of the plurality of sensors. The calibration component 740 may be configured as or otherwise support a means for calibrating a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both. The signal component 745 may be configured as or otherwise support a means for outputting a signal indicative of a calibrated version of the value of the second measurement.

[0166] FIG. 8 shows a block diagram 800 of a wearable device manager 820 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The wearable device manager 820 may be an example of aspects of a wearable device manager or a wearable device manager 720, or both, as described herein. The wearable device manager 820, or various components thereof, may be an example of means for performing various55Attorney Docket No. 048624.00994Oura271-l-WO-PCTaspects of light-based temperature calibration of physiological measurements as described herein. For example, the wearable device manager 820 may include a first measurement component 825, a temperature component 830, a second measurement component 835, a calibration component 840, a signal component 845, a first light component 850, a second light component 855, a first light component 860, a second measurement component 865, a temperature component 870, or any combination thereof. Each of these components, or components of subcomponents thereof (e.g., one or more processors, one or more memories), may communicate, directly or indirectly, with one another (e.g., via one or more buses).

[0167] The first measurement component 825 may be configured as or otherwise support a means for performing a first measurement using the one or more lightemitting components having a wavelength at or above 1100 nanometers. The temperature component 830 may be configured as or otherwise support a means for estimating a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement. The second measurement component 835 may be configured as or otherwise support a means for performing a second measurement using one or more sensors of the plurality of sensors. The calibration component 840 may be configured as or otherwise support a means for calibrating a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both. The signal component 845 may be configured as or otherwise support a means for outputting a signal indicative of a calibrated version of the value of the second measurement.

[0168] In some examples, the first light component 850 may be configured as or otherwise support a means for emitting, from a first light-emitting component of the one or more light-emitting components, first light having a first wavelength at or above 1160 nanometers. In some examples, the first measurement component 825 may be configured as or otherwise support a means for measuring, at a first photodetector of the one or more light-detecting components, a first absorption spectrum point based at least in part on the first light having the wavelength at or above 1160 nanometers. In some examples, the second light component 855 may be configured as or otherwise support a56Attorney Docket No. 048624.00994Oura271-l-WO-PCTmeans for emitting, from a second light-emitting component of the one or more lightemitting components, second light having a second wavelength at or above 1190 nanometers. In some examples, the second measurement component 835 may be configured as or otherwise support a means for measuring, at the first photodetector, a second absorption spectrum point based at least in part on the second light having the wavelength at or above 1190 nanometers.

[0169] In some examples, the first measurement component 825 may be configured as or otherwise support a means for determining, for the first light having the first wavelength , a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point. In some examples, the second measurement component 835 may be configured as or otherwise support a means for determining, for the first light having the first wavelength, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point. In some examples, the temperature component 830 may be configured as or otherwise support a means for determining, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the first light having the first wavelength. In some examples, the temperature component 830 may be configured as or otherwise support a means for determining, a change in temperature that corresponds to the difference between the first absorption coefficient value and the second coefficient value, wherein estimating the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature.

[0170] In some examples, the first light component 850 may be configured as or otherwise support a means for emitting, from a first light-emitting component of the one or more light-emitting components, light having the wavelength at or above 1100 nanometers. In some examples, the first measurement component 825 may be configured as or otherwise support a means for measuring, at a first photodetector of the one or more light-detecting components, a first absorption spectrum point based at least in part on the light having the wavelength at or above 1100 nanometers. In some57Attorney Docket No. 048624.00994Oura271-l-WO-PCTexamples, the second measurement component 835 may be configured as or otherwise support a means for measuring, at a second photodetector of the one or more lightdetecting components, a second absorption spectrum point based at least in part on the light having the wavelength at or above 1100 nanometers.

[0171] In some examples, the first photodetector comprises a first filter configured to allow light having a wavelength below 1180 nanometers to pass through the first filter and block the light having the wavelength at or above 1180 nanometers from passing through the first filter. In some examples, the second photodetector comprises a second filter configured to allow the light having the wavelength at or above 1180 nanometers to pass through the second filter and block the light having the wavelength below 1180 nanometers from passing through the second filter.

[0172] In some examples, the first measurement component 825 may be configured as or otherwise support a means for determining, for the light having the wavelength at or above 1100 nanometers, a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point. In some examples, the second measurement component 835 may be configured as or otherwise support a means for determining, for the light having the wavelength at or above 1100 nanometers, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point. In some examples, the temperature component 830 may be configured as or otherwise support a means for determining, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the light having the wavelength at or above 1100 nanometers. In some examples, the temperature component 830 may be configured as or otherwise support a means for determining, a change in temperature that corresponds to the difference between the first absorption coefficient value and the second coefficient value, wherein estimating the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature.

[0173] In some examples, the first light component 850 may be configured as or otherwise support a means for emitting, from a first light-emitting component of the one 58Attorney Docket No. 048624.00994Oura271-l-WO-PCTor more light-emitting components, light having the wavelength at or above 1100 nanometers. In some examples, the first measurement component 825 may be configured as or otherwise support a means for measuring, at spectrometer of the one or more light-detecting components, a plurality of absorption spectrum points based at least in part on the light having the wavelength at or above 1100 nanometers.

[0174] In some examples, the first measurement component 825 may be configured as or otherwise support a means for determining, from the plurality of absorption spectrum points, a first absorption curve corresponding to the light having the wavelength at or above 1100 nanometers at a first instance. In some examples, the second measurement component 835 may be configured as or otherwise support a means for determining, from a second plurality of absorption spectrum points, a second absorption curve corresponding to the light having the wavelength at or above 1100 nanometers at a second instance. In some examples, the temperature component 830 may be configured as or otherwise support a means for determining, a difference between a first shape of the first absorption curve and a second shape of the second absorption curve. In some examples, the temperature component 830 may be configured as or otherwise support a means for determining, a change in temperature that corresponds to the difference between the first shape of the first absorption curve and the second shape of the second absorption curve, wherein estimating the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature.

[0175] In some examples, the second measurement comprises a PPG measurement, a glucose measurement, a hemoglobin measurement, a fat content measurement, a metabolism measurement, a blood oxygen saturation measurement, or a combination thereof.

[0176] In some examples, the second measurement component 835 may be configured as or otherwise support a means for adjusting the value of the second measurement to be within a threshold range based at least in part on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both.59Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0177] In some examples, the one or more light-detecting components comprise germanium, silicon, or both.

[0178] In some examples, the one or more light-emitting components comprise a laser diode, a light-emitting diode, or both.

[0179] In some examples, the wearable device comprises a wearable ring device.

[0180] FIG. 9 shows a diagram of a system 900 including a device 905 that supports light-based temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The device 905 may be an example of or include components of a device 705 as described herein. The device 905 may include an example of a wearable device 105, as described previously herein. The device 905 may include components for bi-directional communications including components for transmitting and receiving communications with a user device 106 and a server 510, such as a wearable device manager 920, a communication module 910, one or more antennas 915, a sensor component 925, a power module 930, at least one memory 935, at least one processor 940, and a wireless device 950. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 945).

[0181] For example, the wearable device manager 920 may be configured as or otherwise support a means for performing a first measurement using the one or more light-emitting components having a wavelength at or above 1100 nanometers. The wearable device manager 920 may be configured as or otherwise support a means for estimating a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement. The wearable device manager 920 may be configured as or otherwise support a means for performing a second measurement using one or more sensors of the plurality of sensors. The wearable device manager 920 may be configured as or otherwise support a means for calibrating a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both. The wearable device manager 920 may be configured as or otherwise support a means for60Attorney Docket No. 048624.00994Oura271-l-WO-PCToutputting a signal indicative of a calibrated version of the value of the second measurement.

[0182] By including or configuring the wearable device manager 920 in accordance with examples as described herein, the device 905 may support techniques for more accurate PPG measurements, increased signal quality, and achieving highly accurate determination of various metrics, such as blood sugar, hemoglobin, fat content, metabolism, blood oxygen saturation, among other examples. The device 905 may further support improved communication reliability, reduced latency, improved user experience related to reduced processing, reduced power consumption, more efficient utilization of communication resources, improved coordination between devices, longer battery life, and improved utilization of processing capability).

[0183] FIG. 10 shows a flowchart illustrating a method 1000 that supports lightbased temperature calibration of physiological measurements in accordance with aspects of the present disclosure. The operations of the method 1000 may be implemented by a wearable device or its components as described herein. For example, the operations of the method 1000 may be performed by a wearable device as described with reference to FIGs. 5 through 9. In some examples, a wearable device may execute a set of instructions to control the functional elements of the wearable device to perform the described functions. Additionally, or alternatively, the wearable device may perform aspects of the described functions using special-purpose hardware.

[0184] At 1005, the method may include performing a first measurement using the one or more light-emitting components having a wavelength at or above 1100 nanometers. The operations of 1005 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1005 may be performed by a first measurement component 825 as described with reference to FIG. 8.

[0185] At 1010, the method may include estimating a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement. The operations of 1010 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the61Attorney Docket No. 048624.00994Oura271-l-WO-PCToperations of 1010 may be performed by a temperature component 830 as described with reference to FIG. 8.

[0186] At 1015, the method may include performing a second measurement using one or more sensors of the plurality of sensors. The operations of 1015 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1015 may be performed by a second measurement component 835 as described with reference to FIG. 8.

[0187] At 1020, the method may include calibrating a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both. The operations of 1020 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1020 may be performed by a calibration component 840 as described with reference to FIG. 8.

[0188] At 1025, the method may include outputting a signal indicative of a calibrated version of the value of the second measurement. The operations of 1025 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1025 may be performed by a signal component 845 as described with reference to FIG. 8.

[0189] It should be noted that the methods described above describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Furthermore, aspects from two or more of the methods may be combined.

[0190] The following provides an overview of aspects of the present disclosure:

[0191] Aspect 1: A wearable device, comprising: a plurality of sensors configured to acquire physiological data from a user, the plurality of sensors comprising one or more light-emitting components and one or more light-detecting components; a battery configured to provide power to the plurality of sensors; electronic circuitry configured to electrically couple the battery with the plurality of sensors; and one or more processors communicatively coupled with the battery and the plurality of sensors, wherein the one or more processors are configured to: perform a first measurement 62Attorney Docket No. 048624.00994Oura271-l-WO-PCTusing the one or more light-emitting components having a wavelength at or above 1100 nanometers; estimate a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement; perform a second measurement using one or more sensors of the plurality of sensors; calibrate a value of the second measurement using the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both; and output a signal indicative of a calibrated version of the value of the second measurement.

[0192] Aspect 2: The wearable device of aspect 1, wherein the one or more processors are further configured to emit, from a first light-emitting component of the one or more light-emitting components, first light having a first wavelength at or above 1160 nanometers; measure, at a first photodetector of the one or more light-detecting components, a first absorption spectrum point based at least in part on the first light having the wavelength at or above 1160 nanometers; emit, from a second light-emitting component of the one or more light-emitting components, second light having a second wavelength at or above 1190 nanometers; and measure, at the first photodetector, a second absorption spectrum point based at least in part on the second light having the wavelength at or above 1190 nanometers.

[0193] Aspect 3 : The wearable device of aspect 2, wherein the one or more processors are further configured to determine, for the first light having the first wavelength , a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point; determine, for the first light having the first wavelength, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point; determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the first light having the first wavelength ; and determine a change in temperature that corresponds to the difference between the first absorption coefficient value and the second coefficient value, wherein estimating the temperature of water in the blood, or63Attorney Docket No. 048624.00994Oura271-l-WO-PCTthe temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature .

[0194] Aspect 4: The wearable device of any of aspects 1 through 3, wherein the one or more processors are further configured to emit, from a first light-emitting component of the one or more light-emitting components, light having the wavelength at or above 1100 nanometers; measure, at a first photodetector of the one or more lightdetecting components, a first absorption spectrum point based at least in part on the light having the wavelength at or above 1100 nanometers; and measure, at a second photodetector of the one or more light-detecting components, a second absorption spectrum point based at least in part on the light having the wavelength at or above 1100 nanometers.

[0195] Aspect 5: The wearable device of aspect 4, wherein the first photodetector comprises a first filter configured to allow light having a wavelength below 1180 nanometers to pass through the first filter and block the light having the wavelength at or above 1180 nanometers from passing through the first filter, and the second photodetector comprises a second filter configured to allow the light having the wavelength at or above 1180 nanometers to pass through the second filter and block the light having the wavelength below 1180 nanometers from passing through the second filter.

[0196] Aspect 6: The wearable device of any of aspects 4 through 5, wherein the one or more processors are further configured to determine, for the light having the wavelength at or above 1100 nanometers, a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point; determine, for the light having the wavelength at or above 1100 nanometers, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point; determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the light having the wavelength at or above 1100 nanometers ; and determine a change in temperature that corresponds to the difference between the first absorption coefficient value and the second coefficient value, wherein 64Attorney Docket No. 048624.00994Oura271-l-WO-PCTestimating the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature.

[0197] Aspect 7: The wearable device of any of aspects 1 through 6, wherein the one or more processors are further configured to emit, from a first light-emitting component of the one or more light-emitting components, light having the wavelength at or above 1100 nanometers; and measure, at spectrometer of the one or more lightdetecting components, a plurality of absorption spectrum points based at least in part on the light having the wavelength at or above 1100 nanometers.

[0198] Aspect 8: The wearable device of aspect 7, wherein the one or more processors are further configured to determine, from the plurality of absorption spectrum points, a first absorption curve corresponding to the light having the wavelength at or above 1100 nanometers at a first instance; determine, from a second plurality of absorption spectrum points, a second absorption curve corresponding to the light having the wavelength at or above 1100 nanometers at a second instance; determine a difference between a first shape of the first absorption curve and a second shape of the second absorption curve; and determine a change in temperature that corresponds to the difference between the first shape of the first absorption curve and the second shape of the second absorption curve, wherein estimating the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature.

[0199] Aspect 9: The wearable device of any of aspects 1 through 8, wherein the second measurement comprises a PPG measurement, a glucose measurement, a hemoglobin measurement, a fat content measurement, a metabolism measurement, a blood oxygen saturation measurement, or a combination thereof.

[0200] Aspect 10: The wearable device of any of aspects 1 through 9, wherein, to calibrate the value of the second measurement, the one or more processors are further configured to adjust the value of the second measurement to be within a threshold range based at least in part on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both.65Attorney Docket No. 048624.00994Oura271-l-WO-PCT

[0201] Aspect 11 : The wearable device of any of aspects 1 through 10, wherein the one or more light-detecting components comprise germanium, silicon, or both.

[0202] Aspect 12: The wearable device of any of aspects 1 through 11, wherein the one or more light-emitting components comprise a laser diode, a light-emitting diode, or both.

[0203] Aspect 13: The wearable device of any of aspects 1 through 12, wherein the wearable device comprises a wearable ring device.

[0204] The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “exemplary” used herein means “serving as an example, instance, or illustration,” and not “preferred” or “advantageous over other examples.” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

[0205] In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

[0206] Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0207] The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a 66Attorney Docket No. 048624.00994Oura271-l-WO-PCTDSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0208] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described above can be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations. Also, as used herein, including in the claims, “or” as used in a list of items (for example, a list of items prefaced by a phrase such as “at least one of’ or “one or more of’) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an exemplary step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on.”

[0209] Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that can be accessed by a general purpose or special purpose67Attorney Docket No. 048624.00994Oura271-l-WO-PCTcomputer. By way of example, and not limitation, non-transitory computer-readable media can comprise RAM, ROM, electrically erasable programmable ROM (EEPROM), compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0210] The description herein is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.68Attorney Docket No. 048624.00994

Claims

Oura271-l-WO-PCTCLAIMSWhat is claimed is:

1. A wearable device, comprising:a plurality of sensors configured to acquire physiological data from a user, the plurality of sensors comprising one or more light-emitting components and one or more light-detecting components;a battery configured to provide power to the plurality of sensors;electronic circuitry configured to electrically couple the battery with the plurality of sensors; andone or more processors communicatively coupled with the battery and the plurality of sensors, wherein the one or more processors are configured to:perform a first measurement based at least in part on light emitted by the one or more light-emitting components, the light having a wavelength at or above 1100 nanometers;estimate a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement;perform a second measurement using one or more sensors of the plurality of sensors;calibrate the second measurement to generate a calibrated value of the second measurement based at least in part on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both; and output a signal indicative of the calibrated value of the second measurement.

2. The wearable device of claim 1, wherein the light comprises first light having a first wavelength at or above 1160 nanometers and second light having a second wavelength at or above 1190 nanometers, wherein the one or more processors are further configured to:measure, via the one or more light-detecting components, a first absorption spectrum point associated with the first light and a second absorption spectrum point associated with the second light, wherein estimating the temperature of the water in the 69Attorney Docket No. 048624.00994Oura271-l-WO-PCTblood, or the temperature of the water in the surrounding tissue, or both, is based at least in part on the first absorption spectrum point and the second absorption spectrum point.

3. The wearable device of claim 2, wherein the one or more processors are further configured to:determine, for the first light having the first wavelength, a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point;determine, for the first light having the first wavelength, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point;determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the first light having the first wavelength; anddetermine a change in temperature that corresponds to the difference between the first absorption coefficient value and the second absorption coefficient value, wherein estimating the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both, is based at least in part on the change in temperature.

4. The wearable device of claim 1, wherein the one or more processors are further configured to:measure, via a first photodetector of the one or more light-detecting components, a first absorption spectrum point associated with the light having the wavelength at or above 1100 nanometers; andmeasure, via a second photodetector of the one or more light-detecting components, a second absorption spectrum point associated with the light having the wavelength at or above 1100 nanometers, wherein estimating the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both, is based at least in part on the first absorption spectrum point and the second absorption spectrum point.70Attorney Docket No. 048624.00994Oura271-l-WO-PCT5. The wearable device of claim 4, wherein:the first photodetector comprises a first filter configured to allow light having wavelengths below 1180 nanometers to pass through the first filter and block light having wavelengths at or above 1180 nanometers from passing through the first filter, andthe second photodetector comprises a second filter configured to allow light having wavelengths at or above 1180 nanometers to pass through the second filter and block light having wavelengths below 1180 nanometers from passing through the second filter.

6. The wearable device of claim 4, wherein the one or more processors are further configured to:determine, for the light having the wavelength at or above 1100 nanometers, a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point;determine, for the light having the wavelength at or above 1100 nanometers, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point;determine, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the light having the wavelength at or above 1100 nanometers ; anddetermine a change in temperature that corresponds to the difference between the first absorption coefficient value and the second absorption coefficient value, wherein estimating the temperature of the water in the blood, or the temperature of the water in surrounding tissue, or both, is based at least in part on the change in temperature.

7. The wearable device of claim 1, wherein the one or more processors are further configured to:emit, via the one or more light-emitting components, the light having the wavelength at or above 1100 nanometers; and71Attorney Docket No. 048624.00994Oura271-l-WO-PCTmeasure, at spectrometer of the one or more light-detecting components, a plurality of absorption spectrum points associated with the light, wherein estimating the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both, is based at least in part on the plurality of absorption spectrum points.

8. The wearable device of claim 7, wherein the one or more processors are further configured to:determine, from the plurality of absorption spectrum points, a first absorption curve corresponding to the light having the wavelength at or above 1100 nanometers at a first instance;determine, from a second plurality of absorption spectrum points, a second absorption curve corresponding to the light having the wavelength at or above 1100 nanometers at a second instance;determine a difference between a first shape of the first absorption curve and a second shape of the second absorption curve; anddetermine a change in temperature that corresponds to the difference between the first shape of the first absorption curve and the second shape of the second absorption curve, wherein estimating the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both, is based at least in part on determining the change in temperature.

9. The wearable device of claim 1, wherein the second measurement comprises a photoplethysmography (PPG) measurement, a glucose measurement, a hemoglobin measurement, a fat content measurement, a metabolism measurement, a blood oxygen saturation measurement, or a combination thereof.

10. The wearable device of claim 1, wherein, to calibrate the second measurement, the one or more processors are further configured to:adjust the second measurement to be within a threshold range based at least in part on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both.72Attorney Docket No. 048624.00994Oura271-l-WO-PCT11. The wearable device of claim 1, wherein the one or more light-detecting components comprise germanium, silicon, or both.

12. The wearable device of claim 1, wherein the one or more light-emitting components comprise a laser diode, a light-emitting diode, or both.

13. The wearable device of claim 1, wherein the wearable device comprises a wearable ring device.

14. A method performed at a wearable device comprising a plurality of sensors configured to acquire physiological data from a user, the method comprising:performing a first measurement based at least in part on light emitted by one or more light-emitting components of the wearable device, the light having a wavelength at or above 1100 nanometers, the plurality of sensors comprising the one or more lightemitting components;estimating, using one or more processors of the wearable device, a temperature of water in blood, or a temperature of water in surrounding tissue, or both, of a digit of the user based at least in part on the first measurement;performing a second measurement using one or more sensors of the plurality of sensors;calibrating the second measurement to generate a calibrated value of the second measurement based at least in part on the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both; andoutputting a signal indicative of the calibrated value of the second measurement.

15. The method of claim 14, wherein the light comprises first light having a first wavelength at or above 1160 nanometers and second light having a second wavelength at or above 1190 nanometers, wherein the one or more processors are further configured to:measure, via one or more light-detecting components of the wearable device, a first absorption spectrum point associated with the first light and a second absorption spectrum point associated with the second light, wherein estimating the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both,73Attorney Docket No. 048624.00994Oura271-l-WO-PCTis based at least in part on the first absorption spectrum point and the second absorption spectrum point.

16. The method of claim 15, further comprising:determining, for the first light having the first wavelength, a first absorption coefficient value at a first instance based at least in part on the first absorption spectrum point and the second absorption spectrum point;determining, for the first light having the first wavelength, a second absorption coefficient value at a second instance based at least in part on a third absorption point and a fourth absorption point;determining, from a graphical representation of temperature dependent absorption behavior of light at various wavelengths, a difference between the first absorption coefficient value and the second absorption coefficient value for the first light having the first wavelength; anddetermining a change in temperature that corresponds to the difference between the first absorption coefficient value and the second absorption coefficient value, wherein estimating the temperature of water in the blood, or the temperature of water in surrounding tissue, or both, of the digit of the user is based at least in part on determining the change in temperature.

17. The method of claim 14, further comprising:measuring, via a first light-detecting component of the wearable device, a first absorption spectrum point associated with the light having the wavelength at or above 1100 nanometers; andmeasure, via a second light-detecting component of the wearable device, a second absorption spectrum point associated with the light having the wavelength at or above 1100 nanometers, wherein estimating the temperature of the water in the blood, or the temperature of the water in the surrounding tissue, or both, is based at least in part on the first absorption spectrum point and the second absorption spectrum point.

18. The method of claim 17, wherein:the first light-detecting component comprises a first filter configured to allow light having a wavelength below 1180 nanometers to pass through the first filter and74Attorney Docket No. 048624.00994Oura271-l-WO-PCTblock the light having the wavelength at or above 1180 nanometers from passing through the first filter, andthe second light-detecting component comprises a second filter configured to allow the light having the wavelength at or above 1180 nanometers to pass through the second filter and block the light having the wavelength below 1180 nanometers from passing through the second filter.

19. The method of claim 14, wherein the second measurement comprises a photoplethysmography (PPG) measurement, a glucose measurement, a hemoglobin measurement, a fat content measurement, a metabolism measurement, a blood oxygen saturation measurement, or a combination thereof.

20. The method of claim 14, wherein the wearable device comprises a wearable ring device.Attorney Docket No. 048624.00994

Images