KR20230171360A - Electronic device and method for measuring temperature using thereof - Google Patents

Abstract

An electronic device for estimating body temperature is disclosed. According to one embodiment, the electronic device includes a first temperature sensor that measures a first temperature of the surface of the body measurement location, a second temperature sensor that is spaced apart from the first temperature sensor and measures a second temperature inside the body, and a first temperature sensor. a third temperature sensor disposed at a greater distance than the second temperature sensor to measure a third temperature inside the body, and estimating the central temperature of the body measurement location based on the first temperature, second temperature, and third temperature; , may include a processor that estimates the external ambient temperature of the main body based on the second temperature and the third temperature, and estimates the user's body temperature based on the central temperature of the estimated body measurement location and the external ambient temperature of the main body.

Description

Electronic device and method of estimating body temperature using the electronic device {ELECTRONIC DEVICE AND METHOD FOR MEASURING TEMPERATURE USING THEREOF}

This relates to technology for estimating ambient temperature and body temperature using electronic devices.

In general, body temperature is one of the four vital signs and has very important clinical significance. Body temperature sensors can be applied to a variety of applications, such as checking a patient's infection, thermal side effects of drugs, and checking a woman's ovulation period. However, there is a difference between the temperature of peripheral parts of the body, such as wrist temperature or skin temperature, and the core body temperature to be measured, and in particular, the temperature of peripheral parts is highly variable depending on external temperatures such as air temperature. Therefore, it is not easy to accurately estimate core body temperature from a wearable device that measures temperature in the peripheral area. General body temperature sensors can be divided into contact and non-contact types. Contact sensors include sensors that detect changes in electrical resistance, such as RTD (Resistance Temperature Detector) and thermistors, and thermocouples that detect electromotive force. Additionally, non-contact sensors include thermopiles and microbolometers, which measure body temperature by detecting infrared rays radiating from the body surface. General body temperature measurement technology is greatly affected by changes in environmental factors that affect heat transfer, such as changes in external ambient temperature and humidity and air flow.

An electronic device and a body temperature estimation method for estimating ambient air temperature and a user's body temperature using a plurality of sensors including a temperature-based sensor are presented.

According to one aspect, the electronic device includes a first temperature sensor that measures a first temperature of the surface of the body measurement location, a second temperature sensor that is spaced apart from the first temperature sensor and measures a second temperature inside the body, and a first temperature sensor. a third temperature sensor disposed at a greater distance than the second temperature sensor to measure a third temperature inside the body, and estimating the central temperature of the body measurement location based on the first temperature, second temperature, and third temperature; , may include a processor that estimates the external ambient temperature of the main body based on the second temperature and the third temperature, and estimates the user's body temperature based on the central temperature of the estimated body measurement location and the external ambient temperature of the main body.

The processor may obtain heat loss from the body reference position to the body measurement position, and estimate body temperature by correcting the core temperature of the body measurement position based on the obtained heat loss.

The processor may obtain heat loss based on the difference between the first temperature and the external ambient temperature of the main body.

At this time, the electronic device further includes a pulse wave sensor that includes a light source and a detector to measure the user's pulse wave signal, and the processor estimates the first heat flux based on the difference between the first temperature and the second temperature and generates the pulse wave signal. Based on the skin blood flow rate, the central temperature of the body measurement location can be estimated based on the first heat flux, the first temperature, and the skin blood flow rate.

The processor may combine the estimated first heat flux and skin blood flow ratio and the first temperature to estimate the central temperature of the body measurement location.

The processor may estimate the second heat flux based on the difference between the second temperature and the third temperature, and estimate the ambient temperature outside the main body by combining the estimated second heat flux and the third temperature.

The processor determines the resistance value of the heat-conducting material disposed between the second temperature sensor and the third temperature sensor, the resistance value of the heat-conducting material disposed between the third temperature sensor and the surface of the main body, and the resistance value of the surface of the main body. 2 Heat flux can be corrected.

At this time, at least one of the first temperature sensor, the second temperature sensor, and the third temperature sensor may be a thermistor.

The first temperature sensor may be located at a vertical distance of 5 mm or less from the contact surface between the main body and the body.

The third temperature sensor may be located at a vertical distance of 10 mm or less downward from the surface of the main body.

The distance between the first temperature sensor and the second temperature sensor may be within 10 mm, and the distance between the third temperature sensor and the second temperature sensor may be within 50 mm.

The electronic device may further include a display that outputs at least one of the first temperature, the second temperature, the third temperature, the central temperature of the body measurement location, the external ambient temperature of the main body, and the body temperature.

According to one aspect, a method of estimating body temperature by an electronic device includes measuring a first temperature of a surface of a body measurement location by a first temperature sensor, measuring a first temperature of a surface of the body at a body measurement location by a second temperature sensor disposed spaced apart from the first temperature sensor. Measuring the second temperature, measuring the third temperature inside the body by a third temperature sensor disposed at a greater distance from the first temperature sensor compared to the second temperature sensor, measuring the first temperature and the second temperature. estimating the central temperature of the body measurement location as a basis, estimating the external ambient temperature of the main body based on the second temperature and the third temperature, and estimating the central temperature of the body measurement location and the external ambient temperature of the main body based on the estimated central temperature of the body measurement location. It may include the step of estimating body temperature.

In the step of estimating the user's body temperature, the body temperature may be estimated by obtaining heat loss from the body reference position to the body measurement position and correcting the core temperature of the body measurement position based on the obtained heat loss.

In the step of estimating the user's body temperature, heat loss may be obtained based on the difference between the first temperature and the external ambient temperature of the main body.

The step of estimating the central temperature of the body measurement location includes estimating a first heat flux based on the first temperature and the second temperature, and measuring the body based on the first heat flux, the first temperature, and the skin blood flow measured by the pulse wave sensor. The central temperature of a location can be estimated.

In the step of estimating the external ambient temperature of the main body, the second heat flux may be estimated based on the difference between the second temperature and the third temperature, and the external ambient temperature of the main body may be estimated by combining the estimated second heat flux and the third temperature.

The step of estimating the ambient temperature outside the main body includes the resistance value of the heat-conducting material disposed between the second temperature sensor and the third temperature sensor, the resistance value of the heat-conducting material disposed between the third temperature sensor and the surface of the main body, and the surface of the main body. The second heat flux can be corrected based on the resistance value.

A wearable device according to one aspect includes a main body and a strap connected to the main body, wherein the main body includes a first temperature sensor for measuring the user's skin temperature, a second temperature sensor for measuring the first internal temperature of the main body, and a second temperature sensor for measuring the first internal temperature of the main body. Estimating the central temperature of the body measurement position based on a third temperature sensor that measures the internal temperature and the skin temperature and the first internal temperature, and estimating the body external ambient temperature based on the first internal temperature and the second internal temperature, It includes a processor that estimates the user's body temperature based on the central temperature of the body measurement location and the external surrounding temperature of the body, and the second temperature sensor may be disposed between the first temperature sensor and the third temperature sensor in the thickness direction of the body. .

At this time, the wearable device may further include a display, a sensor circuit board to which a first temperature sensor and a PPG (Photoplethysmography) sensor are connected, and a main circuit board to which the processor is connected and disposed between the sensor circuit board and the display. A second temperature sensor may be disposed between the sensor circuit board and the main circuit board, and a third temperature sensor may be disposed between the main circuit board and the display.

According to one aspect, a wearable device includes a main body, a strap connected to both ends of the main body, a first temperature sensor disposed at different distances from the body contact surface to measure a first temperature, a second temperature sensor to measure a second temperature, and A third temperature sensor for measuring the third temperature, and in a state in which the body is worn, estimating a first heat flux based on the first temperature and the second temperature, and measuring the body based on the estimated first heat flux and the first temperature. Estimate a central temperature of the location, estimate a second heat flux based on the second temperature and the third temperature, estimate a body external ambient temperature based on the estimated second heat flux and the third temperature, and estimate the body measurement location. It may include a processor that estimates the user's body temperature based on the core temperature and the external surrounding temperature of the body.

According to another aspect, an electronic device includes a memory storing one or more commands, a communication unit receiving a first temperature, a second temperature, and a third temperature measured by a plurality of temperature sensors, and executing one or more commands to control the user's behavior. a processor for estimating body temperature, wherein the processor estimates a first heat flux based on the first temperature and the second temperature, and estimates a central temperature of the body measurement location based on the estimated first heat flux and the first temperature; , estimating a second heat flux based on the second temperature and the third temperature, estimating a body external ambient temperature based on the estimated second heat flux and the third temperature, and estimating the center temperature of the estimated body measurement position and the body The user's body temperature can be estimated based on the external ambient temperature.

By using a plurality of sensors, including a temperature-based sensor, to estimate the core temperature of the body measurement location and the temperature around the outside of the body, and to estimate the user's body temperature based on this, the accuracy of body temperature estimation can be increased.

1A and 1B are block diagrams of electronic devices according to one embodiment.
2A and 2B are diagrams showing the structure of an electronic device according to an embodiment.
3A, 3B, and 3C illustrate estimating blood flow from characteristics of a pulse wave signal according to one embodiment.
Figure 4 is a block diagram of an electronic device for estimating body temperature according to another embodiment.
Figure 5 is a flowchart of a method for estimating body temperature according to an embodiment.
6 to 14 are diagrams illustrating structures of electronic devices.
Figure 15 is a diagram showing the results of an experiment measuring temperature using a temperature sensor according to one embodiment.

Specific details of other embodiments are included in the detailed description and drawings. The advantages and features of the described technology and methods for achieving them will become clear by referring to the embodiments described in detail below along with the drawings. Like reference numerals refer to like elements throughout the specification.

Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by the terms. Terms are used only to distinguish one component from another. Singular expressions include plural expressions unless the context clearly dictates otherwise. Additionally, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary. Additionally, terms such as “unit” and “module” used in the specification refer to a unit that processes at least one function or operation, which may be implemented as hardware or software, or as a combination of hardware and software.

In addition, expressions such as "at least one", for example, "at least one of a, b and c" can mean only a, only b, only c, a and b, a and c, b and c, or a, It can be interpreted as including b and c.

Electronic devices according to various embodiments described below include, for example, wearable devices, smartphones, tablet PCs, mobile phones, video phones, e-book readers, desktop PCs, laptop PCs, netbook computers, workstations, servers, PDAs, PMPs ( It may include at least one of a portable multimedia player, MP3 player, medical device, and camera. Wearable devices include those that are accessory (e.g., watches, rings, bracelets, anklets, necklaces, glasses, contact lenses, or headmounted-devices (HMDs)), integrated into fabric or clothing (e.g., electronic garments), or attached to the body. It may include at least one of a type (e.g., skin pad or tattoo), or a bioimplantable circuit. However, it is not limited thereto, and may include, for example, various portable medical measuring devices (antioxidant meter, blood sugar meter, heart rate meter, blood pressure meter, or It may include various medical devices such as (temperature measuring device, etc.), magnetic resonance angiography (MRA), magnetic resonance imaging (MRI), computed tomography (CT), imaging device, or ultrasound machine, etc.). However, it is not limited to the above-described devices.

1A and 1B are block diagrams of electronic devices according to one embodiment. 2A and 2B are diagrams showing the structure of an electronic device according to an embodiment.

Referring to FIG. 1A , the electronic device 100 may include a sensor 120 and a processor 130 within the main body 110 of the electronic device 100. The sensor 120 may include a plurality of sensors to obtain data for estimating body temperature, and the processor 130 may estimate the user's body temperature using the data obtained from the sensor 120.

The sensor 120 may include a first temperature sensor 121, a second temperature sensor 122, and a third temperature sensor 123, and the first temperature sensor 121 and the second temperature sensor 122 , and the third temperature sensor 123 may be placed at different locations within the main body 110. For example, the first temperature sensor 121 may be located at a vertical distance (e.g., in the thickness direction) of 5 mm or less from the contact surface of the main body 110 and the user's body, and the third temperature sensor 123 may be located at a distance of 5 mm or less from the contact surface of the main body 110 and the user's body. The vertical distance downward from the contact surface of 110) may be less than 10 mm. Additionally, the vertical distance between the first temperature sensor 121 and the second temperature sensor 122 may be within 10 mm, and the distance between the third temperature sensor 123 and the second temperature sensor 122 may be within 50 mm.

According to another embodiment, at least two of the first temperature sensor 121, the second temperature sensor 122, and the third temperature sensor 123 may be arranged in a straight line, and the first temperature sensor 121 ), the second temperature sensor 122, and the third temperature sensor 123 may be disposed apart from each other in the main body 110. The arrangement of the first temperature sensor 121, the second temperature sensor 122, and the third temperature sensor 123 is not limited thereto. For example, the first temperature sensor 121 and the second temperature sensor 122 may be placed on the rear of the main body 110 to be contacted by the wrist, and the third temperature sensor 123 may be contacted by the finger. It may be placed on the side of the main body 110. At this time, at least one of the first temperature sensor 121, the second temperature sensor 122, and the third temperature sensor 123 may be implemented as a thermistor.

Additionally, referring to FIG. 1B, the sensor 120 may further include a pulse wave sensor 124. The pulse wave sensor 124 (eg, PPG (photoplethysmography) sensor) can measure pulse wave signals including photoplethysmography (PPG) from the user's body and can measure a plurality of pulse wave signals of different wavelengths. At this time, different wavelengths may include green, blue, red, and infrared wavelengths.

The pulse wave sensor 124 includes one or more light sources 125 that irradiate light of different wavelengths and one or more detectors 126 that detect light of different wavelengths scattered or reflected from biological tissues such as the skin surface or blood vessels. can do. The light source 125 may be formed of a light emitting diode (LED), a laser diode (LD), or a phosphor, but is not limited thereto. Additionally, the detector 126 may include a photo diode, a photo transistor (PTr), or an image sensor (eg, a CMOS image sensor). However, it is not limited to this. The pulse wave sensor 124 may be formed of one or more light source arrays and/or one or more detector arrays to measure two or more pulse wave signals. At this time, one or more light sources may radiate light of different wavelengths, and each light source may be placed at different distances from the detector.

According to one embodiment, the light source 125 may radiate LED light at a preset number of times per second to obtain a PPG signal. Additionally, green LED light may be used as the light source 125 to obtain a PPG signal during exercise, and red or red LED light may be used to obtain a PPG signal while a software program application for body temperature measurement is running in the background of the electronic device 100. Infrared LED light may also be used.

Referring to FIG. 2A, the electronic device 100 includes a first temperature sensor 121, a second temperature sensor 122, and a third temperature sensor 123 in the order of distance from the contact surface of the electronic device 100 and the user. can be placed. For example, the first temperature sensor 121 is placed at a location closest to the user's body (e.g., wrist, palm, ankle, auricle, upper arm, etc.) to measure the first temperature (T ₁ ) representing the surface temperature of the body. You can. At this time, the first temperature (T ₁ ) may be skin temperature. The second temperature sensor 122 is disposed spaced apart from the first temperature sensor 121 (e.g., at the top of the first temperature sensor 121) and can measure the second temperature (T ₂ ) inside the main body 110. , the third temperature sensor 123 is disposed at a greater distance from the first temperature sensor than the second temperature sensor (e.g., at the top of the second temperature sensor 122) to set the third temperature (T) inside the main body 110. ₃ ) can be measured. At this time, the second temperature (T ₂ ) and the third temperature (T ₃ ) may be expressed as the first internal temperature and the second internal temperature of the main body 110, respectively.

In addition, a first heat-conducting material 210 may be disposed between the first temperature sensor 121 and the second temperature sensor 122, and a first heat-conducting material 210 may be disposed between the second temperature sensor 122 and the third temperature sensor 123. Two heat-conducting materials 220 may be disposed, and a third heat-conducting material 230 may be disposed on top of the third temperature sensor 123.

The first heat-conducting material 210, the second heat-conducting material 220, and/or the third heat-conducting material 230 may be, for example, an insulator having a thickness of 0.1 mm or more and 20 mm or less, and a heat conductivity of 0.1. It can be a material with W/mK or less (e.g. polyurethane foam). In addition, a separate material is used between the first temperature sensor 121 and the second temperature sensor 122, between the second temperature sensor 122 and the third temperature sensor 123, or on top of the third temperature sensor 123. It is also possible to fill the structure with air, which has very low thermal conductivity, without using .

In another embodiment, the first heat-conducting material 210, the second heat-conducting material 220, and the third heat-conducting material 230 may refer to the entire space including air and structure inside the electronic device 100. . For example, the first heat-conducting material 210 is the entire space including air and/or structure between the first temperature sensor 121 and the second temperature sensor 122, and the second heat-conducting material 220 is the second temperature sensor. (122) and the entire space containing the air and/or structure between the third temperature sensor 123, the third heat-conducting material 230 is the air and/or between the upper part of the third temperature sensor 123 and the upper surface of the main body. It may also mean the entire space including the structure. At this time, the thermal conductivity of the first heat-conducting material 210, the second heat-conducting material 220, and the third heat-conducting material 230 may be 10 W/mK or less.

The processor 130 may estimate the core temperature of the body measurement location and the external surrounding temperature of the body based on data acquired from a plurality of sensors, and calculate the user's body temperature based on the estimated body measurement center temperature and the external surrounding temperature of the body. It can be estimated.

First, the processor 130 estimates the first heat flux (Q 1 ) based on the first temperature (T ₁ ) and the second temperature (T ₂ ), and calculates the estimated first heat flux ( _{Q 1 )} and the first Based on the temperature (T ₁ ), the central temperature of the body measurement location can be estimated.

For example, the processor 130 may estimate the first heat flux (Q ₁ ) based on the temperature difference or temperature gradient between the first temperature (T 1 ) and _the second temperature (T ₂ ). At this time, the temperature gradient is measured at two positions of the first temperature (T ₁ ) and the second temperature (T ₂ ) (e.g., two temperature sensors measuring the first temperature (T ₁ ) and the second temperature (T ₂ ) can represent the temperature change for a certain distance between locations. The term “temperature difference” may include the difference between two temperatures as well as a temperature gradient. In general, assuming that the heat flow is current, the heat transfer characteristics of the material are resistance, and the heat flux is voltage, the heat flow can be expressed by Bohr's law (V=IR), and the temperature difference inside the material (T ₁ -T ₂ ) can be estimated as the heat flux (Q ₁ ). In this case, the central temperature of the body measurement location can be estimated by combining the estimated first heat flux (Q ₁ ) and the first temperature (T ₁ ), which is the surface temperature of the body location to be measured, using Equations 1 to 3. can be expressed.

Here, T _core is the central temperature of the body measurement location, R _skin is a predetermined skin thermal resistance value, R ₁ represents the resistance value of the first heat-conducting material 210, and ε represents the ratio of R _skin and R ₁ . For example, ε may be stored in the storage unit as a predetermined value.

At this time, the processor 130 may estimate skin blood flow based on the pulse wave signal (e.g., PPG signal) measured by the pulse wave sensor 124, and the first heat flux (Q ₁ ) and the first temperature (T ₁ ) In addition, the core temperature of the body measurement location can be estimated by further including the estimated skin blood flow. When estimating the core temperature of a body measurement location, estimating skin blood flow can correct for changes in skin thermal conductivity due to blood flow variability and thus accurately estimate the core temperature of the body measurement location.

For example, the processor 130 estimates the first heat flux (Q ₁ ) based on the temperature difference (T ₁ -T ₂ ) between the first temperature (T 1 ) and the second temperature (T ₂ ), and _the estimated first heat flux By combining (Q ₁ ) and the ratio of skin blood flow and the first temperature (T ₁ ), the central temperature (T _core ) of the body measurement location can be estimated, which can be expressed by Equation 4.

Here, F _s refers to skin blood flow and ε and α refer to predetermined coefficients.

At this time, the processor 130 may extract features from the pulse wave signal and obtain skin blood flow from the extracted features using a model defining the correlation between the features and skin blood flow.

3A, 3B, and 3C illustrate estimating blood flow from characteristics of a pulse wave signal according to one embodiment.

Referring to Figure 3a, the pulse wave signal consists of DC (Direct Current) and AC (Alternating Current) signals, and the DC signal is a constant signal (with a margin) that is reflected from bones, muscles, etc. The AC signal is a signal that changes according to the inflow of blood ejected from the heart among arteries. Referring to Figure 3a, the upper part corresponds to an AC signal that changes with time, and the lower part corresponds to a DC signal that does not change. The AC signal indirectly reflects changes in blood flow because it can indicate whether the amount of incoming arterial blood is increasing or decreasing. Therefore, the processor 130 can extract the area under curve (AUC) 310, which is the area of the AC component of the pulse wave signal, as a feature of the pulse wave signal, and estimate blood flow using the extracted AUC. At this time, the AUC 310 of the AC component of the pulse wave signal may refer to the area between the upper envelope of the pulse wave signal and the baseline connecting the minimum value of the AC component of the pulse wave signal.

However, the method for estimating blood flow is not limited to AUC and may use other AC characteristics, such as the maximum value, minimum value, average, and/or slope of the AC signal within a certain time range. At this time, skin blood flow can be obtained from the extracted AUC using a blood flow estimation model that predefines the correlation between AUC and skin blood flow.

Referring to FIGS. 3B and 3C, the processor 130 outputs a first AC characteristic signal 320 and a second AC characteristic signal ( 330) can be extracted. At this time, each of the first AC characteristic signal 320 and the second AC characteristic signal 330 may be expressed in time and light intensity domains to indicate a change in light reflection intensity over time. The first AC characteristic signal 320 has a shorter period than the second AC characteristic signal 330 and may indicate heart rate. Additionally, the second AC characteristic signal 330 has a longer period than the first AC characteristic signal 320 and may represent the breathing rate.

In addition, as features of the pulse wave signal for blood flow estimation, the time related to the forward wave component of the pulse wave signal and the amplitude corresponding to that time, the time related to the reflected wave component of the pulse wave signal, and the amplitude corresponding to that time can be extracted as feature points. . At this time, feature points related to the forward wave component and the reflected wave component can be extracted based on the second differential signal of the pulse wave signal. For example, the time position of the first minimum point of the second differential signal can be extracted as the time related to the forward wave component, and the time positions of the second and third minimum points can be extracted as the time related to the reflected wave component, respectively. Additionally, the time and/or amplitude of a certain point in a certain section of the pulse wave signal, such as the time and/or amplitude of the maximum amplitude point, the time and/or the internal division point between the time of the maximum amplitude point and the time associated with the forward wave component. The amplitude corresponding to time can be extracted as a feature point. At this time, the internal division point may be a midpoint between two time points or a point where internal division occurs at a predetermined ratio.

Referring again to FIG. 2A, the processor 130 estimates the second heat flux (Q 2 ) based on the second temperature (T ₂ ) and the third temperature (T ₃ ), and the estimated second heat flux (Q _{2 )} And the external ambient temperature of the main body 110 may be estimated based on the third temperature (T ₃ ).

For example, the processor 130 estimates the second heat flux (Q ₂ ) based on the temperature difference (T ₂ -T ₃ ) between the second temperature (T 2 ) and the third temperature (T ₃ ), and estimates the second heat flux (Q ₂ ). The external ambient temperature of the main body 110 can be estimated by combining the heat flux (Q ₂ ) and the third temperature (T ₃ ).

First, the processor 130 may estimate the second heat flux (Q ₂ ) based on the temperature difference (T ₂ -T ₃ ) between the second temperature (T ₂ ) and the third temperature (T ₃ ). For example, assuming that heat transfer from the body measurement position surface to the upper part of the main body 110 is a series circuit and the resulting heat flux is Q _T , the temperature difference between the first temperature (T ₁ ) and the second temperature (T ₂ ), 2 The temperature difference between the temperature (T ₂ ) and the third temperature (T ₃ ), the temperature difference between the third temperature (T ₃ ) and the upper surface temperature of the main body (T _case ), and the upper surface temperature of the main body (T _case ) and the ambient temperature outside the main body. The temperature difference with (T _air ) can be estimated as the same heat flux (Q _T ). In this case, Equation 5 can be derived by Bohr's law (V=IR) inside and above the main body 110 in relation to the heat flow.

Here, R ₂ refers to the resistance value of the second heat-conducting material 220, R ₃ refers to the resistance value of the third heat-conducting material 230, and R _s refers to the resistance value of the upper surface of the main body. At this time, assuming that heat leaks out to the side of the main body 110, the equation shown in Equation 5 does not hold, and each item corresponds to a proportional relationship, so each item can be multiplied by a predetermined coefficient.

Using Equation 5, the body upper surface temperature (T _case ) and the body external ambient temperature (T _air ) can be expressed as Equation 6 and Equation 7 below, respectively.

Next, by substituting Equation 6 into Equation 7, the external ambient temperature of the body (T _air ) can be expressed as Equation 8.

Here, β is a correction coefficient, which means the heat transfer rate according to physical properties, and the processor 130 includes the resistance value (R ₂ ) of the second heat-conducting material 220, the resistance value (R ₃ ) of the third heat-conducting material 230, And a correction coefficient for correcting the second heat flux (T ₂ -T ₃ ) can be calculated based on the resistance value (R _s ) of the upper surface of the main body 200. For example, the processor 130 is the sum of the resistance value (R ₃ ) of the third heat-conducting material 230 and the resistance value (R _s ) of the upper surface 200 of the main body 110 and the second heat-conducting material 220. The correction coefficient can be calculated based on the ratio between resistance values (R ₂ ). The calculated correction coefficient may be stored in advance in the storage unit of the electronic device 100.

That is, according to Equation 8, the processor 130 calculates the result of applying the correction coefficient (β) to the heat flux (Q ₂ ) estimated by the difference between the second temperature and the third temperature (T ₂ -T ₃ ) and the third temperature By combining (T ₃ ), the ambient temperature outside the main body (T _air ) can be measured.

In general, when trying to measure the temperature around an electronic device using a temperature sensor of the electronic device, it is difficult to accurately measure the temperature due to body heat generated by contact between the electronic device and the user. In the above embodiment, the heat flux from the user is estimated using a plurality of temperature sensors, and the surrounding temperature is estimated based on this. By offsetting the effect of body heat, the estimation accuracy of the surrounding temperature of the electronic device can be increased.

Figure 2b is a diagram showing the structure of an electronic device according to another embodiment.

Referring to FIG. 2B, the main body 110 of the electronic device 100 includes a first temperature sensor 121, a second temperature sensor 122, a third temperature sensor 123, and a fourth temperature sensor 124. It can be included. At this time, the fourth temperature sensor 124 is disposed at a greater distance from the first temperature sensor 121 than the third temperature sensor 123 (e.g., at the top of the third temperature sensor 123), so that the main body 110 The fourth internal temperature (T ₄ ) can be measured. In addition, a first heat-conducting material 210 may be disposed between the first temperature sensor 121 and the second temperature sensor 122, and a first heat-conducting material 210 may be disposed between the second temperature sensor 122 and the third temperature sensor 123. 2 A heat-conducting material 220 may be disposed, and a third heat-conducting material 230 may be disposed between the third temperature sensor 123 and the fourth temperature sensor 124, and at the top of the fourth temperature sensor 124. A fourth heat-conducting material 240 may be disposed. At this time, at least one of the first temperature sensor 121, the second temperature sensor 122, the third temperature sensor 123, and the fourth temperature sensor 124 may be a thermistor, and the first heat-conducting material 210 , at least one of the second heat-conducting material 220, the third heat-conducting material 230, and the fourth heat-conducting material 240 may contain air.

At this time, for example, the third temperature sensor 123 may be attached to the structure inside the main body 110, and accordingly, the third temperature sensor 123 may further measure the temperature caused by heat generation of the structure.

The processor 130 measures the second temperature by the second temperature sensor 122, the third temperature by the third temperature sensor 123, and the fourth temperature by the fourth temperature sensor 124 and uses the measured values as a basis. The ambient temperature outside the main body can be measured. For example, the processor 130 estimates the second heat flux (Q ₂ ) based on the temperature difference (T ₂ -T ₃ ) between the second temperature and the third temperature, and the temperature difference between the third temperature and the fourth temperature (T ₃ -T ₄ ), estimate the third heat flux (Q ₃ ), and measure the ambient temperature outside the body based on the estimated second heat flux (Q ₂ ), third heat flux (Q ₃ ), and fourth temperature. You can.

First, when heat is generated in the internal structure of the main body 110 to which the third temperature sensor 123 is attached, the heat flux from the wrist to the upper part of the main body 110 through the third temperature sensor 123 is not the same, and the second There is a difference between the heat flux (Q ₂ ) and the third heat flux (Q ₃ ). For example, due to heat generation of the structure, the second heat flux (Q ₂ ) may become relatively large and the third heat flux (Q ₃ ) may become relatively small, and this can be expressed in Equation 9 according to Bohr's law.

At this time, if the heat (T _in ) introduced by the heat generation of the structure is included in Equation 9, the heat flow from the wrist is based on the temperature difference (T ₄ -T _air ) between the fourth temperature and the upper temperature of the main body 110. It can be expressed as an equivalent equation in Equation 10, including the fourth heat flux (Q ₄ ) estimated as .

Here, R ₂ is the resistance value of the second heat-conducting material 220, R ₃ is the resistance value of the third heat-conducting material 230, and R ₄ is the resistance value of the fourth heat-conducting material 240.

At this time, assuming that heat leaks out to the side of the main body 110, the equation as shown in Equation 10 does not hold, and each item corresponds to a proportional relationship, so each item can be multiplied by a predetermined coefficient.

Using Equation 10, the heat (T _in ) and the temperature (T _air ) at the top of the body introduced by the heat generation of the structure can be expressed as Equation 11 and Equation 12 below, respectively.

Next, by substituting Equation 11 into Equation 12, the temperature at the top of the body (T _air ) can be expressed as Equation 13.

The processor 130 calculates the temperature (T _in ) due to heat generation of the internal structure of the main body according to Equation 11 above into a second heat flux (Q ₂ ) estimated by the difference between the second temperature and the third temperature (T ₂ -T ₃ ). ) and the third heat flux (Q ₃ ) estimated by the difference between the third temperature and the fourth temperature (T ₃ -T ₄ ). In addition, the processor 130 reflects the temperature increase (T _in ) due to heat generation of the internal structure of the main body according to Equation 13 above, and calculates the resistance value (R ₂ ) of the second heat-conducting material and the resistance value (R) of the third heat-conducting material. ₃ ), and the resistance value (R ₄ ) of the fourth heat-conducting material and the estimated second heat flux (Q ₂ ), the third heat flux (Q ₃ ), and the ambient temperature outside the body based on the fourth temperature (T ₄ ). can be measured. At this time, the resistance value (R ₃ ) of the second heat-conducting material, the resistance value (R ₃ ) of the third heat-conducting material, and the resistance value (R ₄ ) of the fourth heat-conducting material may be stored in advance in the storage unit.

In general, when using an electronic device, heat may be generated by the structure inside the body. According to the above embodiment, the accuracy of estimating the ambient temperature outside the electronic device can be increased by offsetting not only the user's body heat but also the influence of structure heat generation.

Next, the processor 130 may estimate the user's body temperature based on the core temperature of the estimated body measurement location and the external ambient temperature of the body.

For example, the processor 130 obtains heat loss from the body reference position to the body measurement position, and corrects the central temperature (T _core ) of the body measurement position based on the obtained heat loss to adjust the body temperature (T _body ). It can be estimated, and this can be expressed by Equation 14. At this time, the body reference location may be, for example, the core, and the body measurement location may be an extremity of the body away from the core, such as the wrist, ankle, auricle, palm, upper arm, etc. The body reference position and body measurement position are not limited to this.

Here, T _loss is the heat loss that occurs from the body reference position to the body measurement position, and may be, for example, heat loss from the core to the wrist.

In general, heat loss can vary depending on the external temperature and occurs through conduction, convection, and radiation. Heat loss by conduction and convection is proportional to the temperature difference and/or temperature gradient between the skin temperature and the external temperature, and heat loss by radiation is proportional to the fourth power difference and/or temperature gradient between the skin temperature and the external temperature. Using this relationship, heat loss can be estimated when estimating body temperature using an electronic device.

For example, the processor 130 may estimate heat loss (T _loss ) based on the temperature difference and/or temperature gradient between the first temperature (T ₁ ) and the external ambient temperature (T _air ) of the main body, which is expressed in Equation 15 It can be expressed by .

Here, г and δ correspond to predetermined heat loss coefficients. г and δ may be stored in advance in the storage unit of the electronic device 100.

Figure 4 is a block diagram of an electronic device for estimating body temperature according to another embodiment.

Referring to FIG. 4 , the electronic device 400 may include a sensor 420, a processor 430, a storage unit 440, an output unit 450, and a communication unit 460 within the main body 410. At this time, since the configurations of the sensor 420 and the processor 430 are the same as those of the sensor 120 and the processor 130 in the embodiments of FIGS. 1A and 1B, detailed descriptions are omitted.

The storage unit 440 may store information related to body temperature estimation. For example, temperature data acquired through the sensor 420, pulse wave signal, resistance value of the heat-conducting material, correction coefficient, heat loss coefficient, processing results of the processor 430, such as heat flux, center temperature estimate of the body measurement location, body External ambient temperature estimates, etc. can be saved.

The storage unit 440 is a flash memory type, hard disk type, multimedia card micro type, or card type memory (for example, SD or XD memory, etc.). , Random Access Memory (RAM), Static Random Access Memory (SRAM), Read-Only Memory (ROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Programmable Read-Only Memory (PROM), magnetic memory, It includes, but is not limited to, storage media such as magnetic disks and optical disks.

The output unit 450 may provide the processing results of the processor 430 to the user. For example, the output unit 450 may display the estimated body temperature of the processor 430 on the display. At this time, information can be provided to the user by adjusting the color or line thickness so that the user can easily recognize the estimated body temperature, and information about continuous changes in body temperature over time can also be provided to the user. In addition, the output unit 450 may output at least one of the first temperature, the second temperature, the third temperature, the central temperature of the body measurement location, the external ambient temperature of the body, body temperature, and body temperature-related guide information through the display. . At this time, the output unit 450 may provide body temperature information to the user in a non-visual manner such as voice, vibration, or tactile sensation using a voice output module such as a speaker or a haptic module, either alone or together with a visual display.

The communication unit 460 can communicate with external devices to transmit and receive various data related to body temperature estimation. External devices may include information processing devices such as smartphones, tablet PCs, desktop PCs, and laptop PCs. For example, the communication unit 460 can transmit the body temperature measurement results to an external device such as a smartphone, and for example, the user can monitor the body temperature over time through the smartphone.

The communication unit 460 includes Bluetooth communication, BLE (Bluetooth Low Energy) communication, Near Field Communication (NFC), WLAN communication, Zigbee communication, Infrared Data Association (IrDA) communication, and WFD. A variety of wired and wireless communication technologies including (Wi-Fi Direct) communication, UWB (ultra-wideband) communication, Ant+ communication, WIFI communication, RFID (Radio Frequency Identification) communication, 3G communication, 4G communication, 5G communication, and 6G communication. You can use to communicate with external devices. However, it is not limited to this.

Figure 5 is a flowchart of a method for estimating body temperature according to an embodiment.

FIG. 5 is an example of a method for estimating body temperature performed by the electronic devices 100 and 400 according to the embodiments of FIGS. 1 and 4 . Since it has been described in detail previously, it will be briefly explained to avoid redundant explanation.

Referring to FIG. 5, the electronic device may measure the first temperature of the surface of the body measurement location by a first temperature sensor within the main body (510), and measure the first temperature of the surface of the body measurement location by a second temperature sensor disposed spaced apart from the first temperature sensor. The second temperature can be measured (520), and the third temperature inside the body can be measured by a third temperature sensor disposed at a greater distance from the first temperature sensor than the second temperature sensor (530). .

Next, the electronic device may estimate the first heat flux based on the measured first temperature and the second temperature, and estimate the central temperature of the body measurement location based on the estimated first heat flux and first temperature (540 ). At this time, the electronic device may estimate the first heat flux based on the temperature difference and/or temperature gradient between the first temperature and the second temperature. Additionally, the electronic device estimates skin blood flow based on the pulse wave signal (e.g., PPG signal) measured by the pulse wave sensor, and the first heat flux, the first temperature, and the central temperature of the body measurement location based on the estimated skin blood flow. can also be estimated. Additionally, the electronic device may estimate skin blood flow based on one or a combination of the PPG signal and the ECG signal. For example, electronic devices may be The central temperature of the body measurement location can be estimated by combining the ratio of the first heat flux and skin blood flow and the first temperature.

Next, the electronic device may estimate a second heat flux based on the measured second temperature and the third temperature, and estimate the ambient temperature outside the main body based on the estimated second heat flux and third temperature (550). . For example, the electronic device may estimate the second heat flux based on the temperature difference and/or temperature gradient between the second temperature and the third temperature, and estimate the ambient temperature outside the main body by combining the estimated second heat flux and the third temperature. At this time, the electronic device determines the resistance value of the heat-conducting material disposed between the second temperature sensor and the third temperature sensor, the resistance value of the heat-conducting material disposed between the third temperature sensor and the surface of the main body, and the resistance value of the surface of the main body. Based on this, the second heat flux can be corrected.

Next, the electronic device may estimate the user's body temperature based on the core temperature of the estimated body measurement location and the external ambient temperature of the body (560). For example, the body temperature can be estimated by obtaining heat loss from the body reference position to the body measurement position and correcting the central temperature of the body measurement position based on the obtained heat loss. At this time, heat loss may be obtained based on the temperature difference and/or temperature gradient between the first temperature and the external surrounding temperature of the main body.

Next, the electronic device may provide the estimated user's body temperature information through the output unit (570). At this time, the body temperature information is not only the estimated user's body temperature, but also continuous body temperature information measured over time, the first temperature, the second temperature, the third temperature, the center temperature of the body measurement location, the temperature around the outside of the body, body temperature-related guide information, etc. may include.

6 to 14 are diagrams illustrating structures of electronic devices.

Referring to FIG. 6, the electronic device may be implemented as a smart watch-type wearable device 600 and may include a main body (MB) and a wrist strap (ST).

The main body MB may be formed to have various shapes. A battery that supplies power to various components may be built into the main body (MB) and/or strap (ST). The strap (ST) is connected to both ends of the main body, allows the main body to be worn on the user's wrist, and may be flexible so that it can be bent into a shape that surrounds the user's wrist. The strap ST may be composed of a first strap and a second strap that are separated from each other. One end of the first strap and the second strap are respectively connected to both sides of the main body MB, and may be fastened to each other using a fastening means formed on the other end of the first strap and the second strap. At this time, the fastening means may be formed by magnetic coupling, Velcro coupling, pin coupling, etc., but is not limited thereto. Additionally, the strap ST is not limited to this and may be formed as an integral piece, such as a band, that are not separated from each other.

The main body (MB) may include a sensor 610, a processor, an output unit, a storage unit, and a communication unit. However, depending on the size and shape of the form factor, some of the output unit, storage unit, and communication unit may be omitted.

The sensor 610 is disposed at different distances from the body contact surface and may include a first temperature sensor for measuring the first temperature, a second temperature sensor for measuring the second temperature, and a third temperature sensor for measuring the third temperature. You can. At this time, the first temperature may be the surface temperature of the body measurement location, and the second and third temperatures may be different temperatures inside the body measured by the second and third temperature sensors that are spaced apart from each other. . Additionally, the sensor 610 may further include a pulse wave sensor (eg, PPG sensor) and an electrocardiography (ECG) sensor that includes a light source and a detector and measures the user's pulse wave signal. One of the electrodes of the ECG sensor may be placed on the side of the main body MB, for example, on the manipulation unit 620.

At this time, the sensor 610 may be placed on the back of the main body (MB) so that when the main body (MB) is worn on the user's wrist, it can contact the upper part of the user's wrist and obtain data for measuring body temperature.

FIGS. 7A and 7B are diagrams showing the arrangement of sensors in a wearable device.

Referring to FIGS. 7A and 7B, the pulse wave sensor 740 and the first temperature sensor 710 including a plurality of light sources 741 and a detector 742 detect the user's wrist ( or other body parts). At this time, the first temperature sensor 710 and the pulse wave sensor 740 may be electrically connected to the sensor circuit board 750. Additionally, the second temperature sensor 720 may be placed directly above or apart from the first temperature sensor 710, and the third temperature sensor 730 may be used to measure the ambient temperature outside the main body. ) can be placed closer to the front of the main body.

In particular, referring to FIG. 7A, the second temperature sensor 720 and the third temperature sensor 730 may be disposed on the first support structure 780A and the second support structure 780B, respectively. At this time, the second temperature sensor 720 may be placed at any position between the first temperature sensor 710 and the main circuit board 760 in the vertical direction (eg, thickness direction) of the wearable device. The third temperature sensor 730 may be placed anywhere in the vertical direction between the main circuit board 760 and the display panel 770. Any two or all of the first temperature sensor 710, the second temperature sensor 720, and the third temperature sensor 730 may be arranged in a straight line in the vertical direction of the wearable device.

Figure 7c is a diagram showing the arrangement and size of the temperature sensor and heat-conducting material.

The temperature sensors S1 and S2 are any two of the first temperature sensor 121, the second temperature sensor 122, the third temperature sensor 123, and the fourth temperature sensor 124 shown in FIGS. 2A to 2B. This may correspond to a temperature sensor. The thermally conductive material (C) may correspond to any thermally conductive material (eg, thermally conductive material 210, 220, 230 or 240) included between the two temperature sensors (S1 and S2). At this time, the heat-conducting material (C) may be placed directly on one or both of the temperature sensors (S1 and S2). For example, there may be no space between the heat-conducting material (C) and each of the temperature sensors (S1 and S2), or the heat-conducting material (C) and one of the temperature sensors (S1 and S2) may be in contact and the other not in contact. The temperature sensor may be spaced or spaced from the heat-conducting material (C).

For example, two temperature sensors (S1 and S2) and a heat-conducting material (C) may be placed in the area between the contact surface and the display panel 770. In order to implement a body temperature measuring device into a smart watch, there may be restrictions on the height of the temperature sensors (S1 and S2) and the height of the heat-conducting material (C) (or the distance between the temperature sensors (S1 and S2)), which may be limited by the temperature sensor (S1 and S2). This is because the area of the smart watch that can accommodate S1 and S2) is small. For example, the height of the area that can accommodate the temperature sensors (S1 and S2) in a smart watch may be 1 mm to 1.5 mm. Given the limited height of the smartwatch area, the height of the heat-conducting material (C) can decrease as the height of the temperature sensors (S1 and S2) increases, but the minimum temperature difference between the two temperature sensors (S1 and S2), e.g., 0.3 In order to obtain temperature (°C) and estimate body temperature based on the temperature difference, a certain distance is required between the two temperature sensors (S1 and S2). The temperature sensors (S1 and S2) may have a slight error rate (e.g. ± 0.1 ℃), so if the target temperature difference between the two temperature sensors (S1 and S2) is set to less than 0.3 ℃, the two temperature sensors (S1 and S2) It may be difficult to reliably measure the temperature difference between S2). Based on this understanding, the minimum target temperature difference between the two temperature sensors (S1 and S2) can be set to 0.3℃, and the heat transfer simulation shows the This was performed by changing the height and the height of the heat-conducting material (C).

Area height H temperature sensor height heat conduction material
height temperature difference 1mm 0.1 0.8 0.648 0.2 0.6 0.486 0.3 0.4 0.324 0.4 0.2 0.162 1.1mm 0.1 0.9 0.730 0.2 0.7 0.567 0.3 0.5 0.405 0.4 0.3 0.243 1.2mm 0.1 One 0.811 0.2 0.8 0.648 0.3 0.6 0.486 0.4 0.4 0.324 0.5 0.2 0.162 1.3mm 0.1 1.1 0.892 0.2 0.9 0.730 0.3 0.7 0.567 0.4 0.5 0.405 0.5 0.3 0.243 1.4mm 0.1 1.2 0.973 0.2 One 0.811 0.3 0.8 0.648 0.4 0.6 0.486 0.5 0.4 0.324 0.6 0.2 0.162 1.5mm 0.1 1.3 1.054 0.2 1.1 0.892 0.3 0.9 0.730 0.4 0.7 0.567 0.5 0.5 0.405 0.6 0.3 0.243

Referring to Table 1, when the target temperature difference between the two temperature sensors (S1 and S2) is 0.3°C or more, the height of each temperature sensor (S1 and S2) is at least 0.3mm (i.e. greater than 0.3mm, preferably between 0.3mm and 0.3mm). 0.5 mm), the height of the heat-conducting material (C) may be set to a height of at least 0.4 mm (preferably 0.4 mm to 1.3 mm).

Referring again to FIGS. 7A, 7B, and 7C, the first temperature sensor 710 is placed as close as possible to the contact surface, and the third temperature sensor 730 is placed as close as possible to the display panel 770 to enable relatively accurate temperature estimation. It may be possible.

Additionally, referring to FIG. 8 , the sensor 810 can be placed not only on the rear of the main body (MB) but also on the wrist strap (ST) to acquire data.

Referring again to FIG. 6, the manipulation unit 620 may be formed on the side of the main body MB as shown. The manipulation unit 620 may receive a user's command and transmit it to the processor. Additionally, the manipulation unit 620 may include a power button that turns the wearable device 600 on/off.

The processor mounted on the main body (MB) may be electrically connected to various components, including the sensor 610. The processor may estimate the user's body temperature using data obtained from a plurality of sensors 610. For example, with the main body MB worn, the processor estimates a first heat flux based on the first temperature and the second temperature, and the center of the body measurement position based on the estimated first heat flux and the first temperature. Estimating a temperature, estimating a second heat flux based on the second temperature and the third temperature, estimating an ambient temperature outside the body based on the estimated second heat flux and the third temperature, and estimating a central temperature at the estimated body measurement location. The user's body temperature can be estimated based on the external ambient temperature of the body. At this time, the processor can obtain heat loss from the body reference location (e.g., core) to the body measurement location (e.g., wrist), and estimate body temperature by correcting the core temperature of the body measurement location based on the obtained heat loss. there is.

A display is provided on the front of the main body (MB), and various application screens including body temperature information, time information, received message information, etc. can be displayed. For example, a display could show an estimate of body temperature. At this time, if the estimated body temperature value is outside the normal range, warning information can be provided to the user by adjusting the color or line thickness or displaying the normal range so that the user can easily recognize it. Additionally, at the user's request, not only can the current body temperature estimate be displayed, but continuous body temperature estimates over time can be displayed on the display and provided to the user. In addition, the amount of change in body temperature, for example, change in body temperature during the day, can be shown in a graph, and whether or not the user sleeps well according to the change in body temperature can also be displayed on the display. Information that can be displayed on the display includes, but is not limited to, body temperature information as well as measured first temperature, second temperature, third temperature, core temperature of the body measurement location, body external ambient temperature, and body temperature-related guide information, etc. No.

Referring to FIG. 9, the electronic device may also be implemented as an ear wearable device 900.

The ear wearable device 900 may include a main body and an ear strap. Users can wear the ear straps by hanging them around their ears. The ear strap can be omitted depending on the shape of the ear wearable device 900. The body can be inserted into the user's external auditory meatus. A sensor 910 may be mounted on the main body. Next, the wearable device 900 can provide the body temperature estimation result to the user through sound or transmit it to an external device such as a mobile, tablet, PC, etc. through a communication module provided inside the main body.

Referring to FIG. 10, the electronic device may be implemented by a combination of an ear-type wearable device and a mobile device such as a smartphone. However, this is only an example and a combination of various electronic devices is possible. As an example, a processor that estimates body temperature may be mounted on the main body of the mobile device 1000. When the processor of the mobile device 1000 receives a request to measure body temperature, it can communicate with the communication unit mounted inside the main body of the wearable device 900 through the communication unit and control acquisition of data by the sensor 910. In addition, upon receiving data such as the first temperature, second temperature, third temperature, and/or pulse wave signal from the wearable device 900, the processor estimates the body temperature and displays the temperature of the mobile device 1000 as shown through the output unit. The results and body temperature-related information can be output on the display. For example, at the user's request, not only the current body temperature estimate but also continuous body temperature estimate over time can be displayed on the display and provided to the user. In addition, the amount of change in body temperature, for example, change in body temperature during the day, can be shown in a graph, and whether or not you are sleeping well according to the change in body temperature can also be displayed on the display.

Referring to FIG. 11A, the electronic device may be implemented as a mobile device 1100 such as a smart phone.

The mobile device 1100 may include a housing and a display panel. The housing may form the exterior of the mobile device 1100. A display panel and a cover glass may be sequentially arranged on the first side of the housing, and the display panel may be exposed to the outside through the cover glass. A sensor 1110, a camera module, and/or an infrared sensor may be disposed on the second side of the housing.

In one embodiment, a plurality of sensors capable of acquiring data from the user may be placed on the rear of the mobile device 1100, and a fingerprint sensor on the front of the mobile device 1100, a side power button, a volume button, or a mobile device ( 1100), sensors, etc. are placed in separate locations on the front and back of the device to estimate body temperature.

In addition, when a user requests body temperature estimation by running an application mounted on the mobile device 1100, data is acquired using the sensor 1110, body temperature is estimated using the processor in the mobile device, and the estimated value is sent to the user as a video. and/or may be provided with sound.

Additionally, the sensor 1110 may be placed not only inside the mobile device 1100 but also outside close to the body measurement location.

Referring to FIG. 11B, the sensor 1110 may be placed, for example, inside a shoe close to a body measurement location (e.g., sole or ankle) to obtain data. At this time, the acquired data is transmitted to the mobile device 1100 through the communication unit, and the processor in the mobile device 1100 may estimate the body temperature and output the result through the display as shown.

Referring to FIG. 12, the electronic device can also be implemented by a combination of a watch-type wearable device and a mobile device such as a smartphone. As an example, a memory, a communication unit, and a processor that estimates body temperature may be mounted on the main body of the mobile device 1200. When the processor of the mobile device receives a request to measure body temperature, it can control the processor to obtain data by communicating with a communication unit mounted inside the main body of the wearable device 1210 through the communication unit. In addition, upon receiving data such as the first temperature, second temperature, third temperature, and pulse wave signal from the wearable device, the processor can estimate the body temperature and output the results on the display of the mobile device as shown through the output unit. there is.

Referring to FIG. 13, the electronic device 1300 may also be implemented on the steering wheel of a car.

For example, the electronic device 1300 may be implemented on the steering wheel of a car where the surface of the driver's palm is in contact to estimate the driver's body temperature. At this time, the electronic device 1300 provides the body temperature estimation result to the user through sound through an electronic device in the vehicle, or to an external device such as a mobile, tablet, PC, or other medical device through a communication module provided inside the electronic device 1300. It can be transmitted, etc. Additionally, the electronic device 1300 may transmit the body temperature estimation result to the electronic device within the vehicle, and the electronic device within the vehicle may adjust the temperature inside the vehicle based on this.

Referring to FIG. 14, the electronic device 1400 may also be implemented as a patch type.

For example, the electronic device 1400 may be fixedly placed with a strap at a body measurement location (eg, upper arm) to estimate the user's body temperature. At this time, the electronic device 1400 provides the estimated body temperature to the user through sound or a display, or to an external device such as a mobile, tablet, PC, or other medical device through a communication module provided inside the electronic device 1400. Can be transmitted.

Figure 15 is a diagram showing simulation results of temperature estimation according to one embodiment.

Since body temperature estimation is based on the temperature and the temperature at the center of the body measurement location, the more accurate the expected temperature, the more accurate the body temperature estimation can be. As shown in FIG. 15, the main body 110 of the electronic device may include an upper surface and a lower surface. When the lower surface touches the user's wrist, the user's body heat may be transferred to the lower surface of the main body and then transferred to the upper surface of the main body. Referring to FIG. 15 , the main body 110 may include a first temperature sensor 121 and a second temperature sensor 122 disposed in a vertical direction (eg, thickness direction) of the main body 110 . In addition, the main body 110 has a third temperature sensor located further away from the lower surface of the main body 110 (e.g., the surface where the main body contacts the user's wrist) than the first temperature sensor 121 and the second temperature sensor 122. It may include a temperature sensor 123. At this time, the first temperature sensor 121 may be placed at a vertical distance of 5 mm or less (e.g., in the thickness direction) from the contact surface, and the third temperature sensor 123 may be placed at a vertical distance of 10 mm or less from the contact surface of the main body 110. can be placed in In addition, the vertical distance between the first temperature sensor 121 and the second temperature sensor 122 may be 10 mm or less, and the distance between the third temperature sensor 123 and the second temperature sensor 122 may be within 10 mm to 50 mm. there is.

The first heat-conducting material 210 may be disposed between the first temperature sensor 121 and the second heat-conducting material 220, and the second heat-conducting material 220 may be disposed between the second temperature sensor 122 and the third temperature sensor. 123 , and the third heat-conducting material 230 may be disposed between the third temperature sensor 123 and the upper surface 200 of the main body 110. At this time, at least one of the first heat-conducting material 210, the second heat-conducting material 220, and the third heat-conducting material 230 may have a minimum thickness of 0.4 mm (that is, 0.4 mm or more, preferably 0.4 mm). mm to 1.3 mm) and may be an insulator (e.g., polyurethane foam, air) with a thermal conductivity of 0.1 W/mk or less. In addition, at least one of the first temperature sensor 121, the second temperature sensor 122, and the third temperature sensor 123 has a minimum height of 0.3 mm (i.e., 0.3 mm or more, preferably 0.3 mm to 0.5 mm). It can be set to have.

According to one embodiment, by arranging the first temperature sensor 121, the second temperature sensor 122, and the third temperature sensor 123, the electronic device can estimate the temperature with high accuracy as follows.

Temperature sensor T3 Temperature sensor T2 actual temperature estimated temperature 20.96℃ 22.62℃ 15℃ 14.96℃ 24.77℃ 26.10℃ 20℃ 19.98℃ 29.18℃ 30.34℃ 25℃ 25.00℃ 32.39℃ 33.05℃ 30℃ 30.00℃

As shown in Table 2, the temperature estimated according to one embodiment has a difference from the actual temperature of 0.96 ℃, 0.02 ℃, 0.00 ℃, and 0.00 ℃. Therefore, it can be seen that it was accurately estimated.

Meanwhile, these embodiments can be implemented as computer-readable codes on a computer-readable recording medium. Computer-readable recording media include all types of recording devices that store data that can be read by a computer system.

Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, and optical data storage devices, and can also be implemented in the form of a carrier wave (e.g., transmission via the Internet). Includes. Additionally, the computer-readable recording medium can be distributed in a computer system connected to a network, so that the computer-readable code can be stored and executed in a distributed manner. And functional programs, codes, and code segments for implementing the present embodiments can be easily deduced by programmers in the technical field to which the present invention pertains.

A person skilled in the art to which this disclosure pertains will understand that it can be implemented in other specific forms without changing the disclosed technical idea or essential features. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

100, 400: Electronic devices
110: body
120, 420: sensor
130, 430: processor
121: first temperature sensor 122: second temperature sensor
123: third temperature sensor 124: fourth temperature sensor
440: storage unit
450: output unit
460: Department of Communications

Claims (20)

a first temperature sensor that measures a first temperature of the body measurement location surface;
a second temperature sensor that is spaced apart from the first temperature sensor and measures a second temperature inside the main body;
a third temperature sensor disposed at a greater distance from the first temperature sensor than the second temperature sensor to measure a third temperature inside the main body; and
Estimating a central temperature of the body measurement location based on the first temperature, second temperature, and third temperature, estimating an external ambient temperature of the body based on the second temperature and the third temperature, and estimating the estimated body measurement An electronic device comprising a processor to estimate the user's body temperature based on the central temperature of the location and the ambient temperature outside the body. According to paragraph 1,
The processor is
An electronic device that acquires heat loss from a body reference position to the body measurement position and estimates body temperature by correcting the central temperature of the body measurement position based on the obtained heat loss. According to paragraph 2,
The processor is
An electronic device that obtains the heat loss based on a difference between the first temperature and an external ambient temperature of the main body. According to paragraph 1,
Further comprising a pulse wave sensor that measures the user's pulse wave signal, including a light source and a detector,
The processor is
Estimating a first heat flux based on the difference between the first temperature and the second temperature,
Estimating skin blood flow based on the pulse wave signal,
An electronic device for estimating a central temperature of the body measurement location based on the first heat flux, the first temperature, and the skin blood flow. According to paragraph 4,
The processor is
An electronic device for estimating a central temperature of the body measurement location by combining the ratio of the estimated first heat flux and the skin blood flow with the first temperature. According to paragraph 1,
The processor is
An electronic device that estimates the second heat flux based on the difference between the second temperature and the third temperature, and estimates the external ambient temperature of the main body by combining the estimated second heat flux and the third temperature. According to clause 6,
The processor is
Based on the resistance value of the heat-conducting material disposed between the second temperature sensor and the third temperature sensor, the resistance value of the heat-conducting material disposed between the third temperature sensor and the surface of the main body, and the resistance value of the surface of the main body. An electronic device for correcting the second heat flux. According to paragraph 1,
An electronic device wherein at least one of the first temperature sensor, the second temperature sensor, and the third temperature sensor is a thermistor. According to paragraph 1,
The first temperature sensor is
An electronic device located at a vertical distance of 5 mm or less from the contact surface of the main body and the body. According to paragraph 1,
The third temperature sensor is
An electronic device located at a vertical distance of 10 mm or less downward from the surface of the main body. According to paragraph 1,
The electronic device wherein the distance between the first temperature sensor and the second temperature sensor is within 10 mm, and the distance between the third temperature sensor and the second temperature sensor is within 50 mm. According to paragraph 1,
The electronic device further includes a display that outputs at least one of the first temperature, the second temperature, the third temperature, the central temperature of the body measurement location, the external ambient temperature of the main body, and the body temperature. In a method for an electronic device to estimate body temperature,
measuring a first temperature of the body measurement location surface by a first temperature sensor;
measuring a second temperature inside the main body using a second temperature sensor spaced apart from the first temperature sensor;
measuring a third temperature inside the main body by a third temperature sensor disposed at a greater distance from the first temperature sensor than the second temperature sensor;
estimating a central temperature of the body measurement location based on the first temperature and the second temperature;
estimating an external ambient temperature of the main body based on the second temperature and the third temperature; and
A body temperature estimation method comprising estimating the user's body temperature based on the estimated core temperature of the body measurement location and the external ambient temperature of the body. According to clause 13,
The step of estimating the user's body temperature is
A body temperature estimation method that obtains heat loss from a body reference position to the body measurement position and estimates body temperature by correcting the core temperature of the body measurement position based on the obtained heat loss. According to clause 14,
The step of estimating the user's body temperature is
A body temperature estimation method for obtaining the heat loss based on the difference between the first temperature and the external ambient temperature of the main body. According to clause 13,
The step of estimating the central temperature of the body measurement location is
Estimating a first heat flux based on the first temperature and the second temperature,
A body temperature estimation method for estimating the central temperature of the body measurement location based on the first heat flux, first temperature, and skin blood flow measured by a pulse wave sensor. According to clause 13,
The step of estimating the external ambient temperature of the main body is
A body temperature estimation method for estimating the second heat flux based on the difference between the second temperature and the third temperature, and estimating the external ambient temperature of the main body by combining the estimated second heat flux and the third temperature. According to clause 17,
The step of estimating the external ambient temperature of the main body is
Based on the resistance value of the heat-conducting material disposed between the second temperature sensor and the third temperature sensor, the resistance value of the heat-conducting material disposed between the third temperature sensor and the surface of the main body, and the resistance value of the surface of the main body. A body temperature estimation method that corrects the second heat flux. main body; and
Includes a strap connected to the main body,
The body is
A first temperature sensor that measures the user's skin temperature; a second temperature sensor measuring the first internal temperature of the main body; a third temperature sensor measuring a second internal temperature of the main body; and
Estimating a central temperature of the body measurement location based on the skin temperature and the first internal temperature, estimating a body external ambient temperature based on the first internal temperature and the second internal temperature, and centering the body measurement location A processor that estimates the user's body temperature based on the temperature and the external ambient temperature of the main body,
The second temperature sensor is a wearable device disposed between the first temperature sensor and the third temperature sensor in the thickness direction of the main body. According to clause 19,
display;
a sensor circuit board to which the first temperature sensor and a photoplethysmography (PPG) sensor are connected; and
Further comprising a main circuit board on which the processor is connected and disposed between the sensor circuit board and the display,
The second temperature sensor is disposed between the sensor circuit board and the main circuit board, and the third temperature sensor is disposed between the main circuit board and the display.