Electronic device and method of measuring body temperature using the same

1 . A wearable device comprising:

a main body case;

a display disposed on an outer surface of the main body case;

wherein the main body case contains:

a first temperature sensor configured to measure a first temperature at a first position;

a second temperature sensor configured to measure a second temperature at a second position;

a third temperature sensor configured to measure a third temperature, wherein the second temperature sensor is disposed between the first temperature sensor and the third temperature sensor in a thickness direction of the wearable device, and wherein the first temperature sensor, the second temperature sensor, and the third temperature sensor are arranged in a straight line in the thickness direction;

a first thermally conductive material provided between the first temperature sensor and the second temperature sensor, a second thermally conductive material provided between the second temperature sensor and the third temperature sensor, and a third thermally conductive material provided between the third temperature sensor and an inner surface of the main body case; and

a processor configured to:

calculate an ambient temperature by

calculating a heat transfer coefficient by dividing a sum of a resistance of the third thermally conductive material and a resistance of the main body case by a resistance of the second thermally conductive material, and

subtracting, from the third temperature, a product of the heat transfer coefficient and a difference between the second temperature and the third temperature; and

calculate a heat loss between two reference body points based on a difference between a reference core temperature and the ambient temperature; and

obtain a body temperature by correcting the first temperature based on the heat loss.

2 . The wearable device of claim 1 , wherein the first temperature sensor is disposed at a distance of 10 mm or less from the main body case of the wearable device, and a thermal conductivity of the first thermally conductive material is less than 0.1 W/mK.

3 . The wearable device of claim 1 , wherein the second temperature sensor is disposed at a distance of 10 mm or less from the first temperature sensor.

4 . The wearable device of claim 1 , wherein the first temperature sensor is mounted on the main body case of the wearable device, and the second temperature sensor is mounted under the display.

5 . The wearable device of claim 1 , wherein either the first position or the second position is at a printed circuit board on which the processor is mounted.

6 . The wearable device of claim 1 , wherein the processor is further configured to estimate a first body temperature by inputting the first temperature to a body temperature estimation model, and obtain a second body temperature based on the first body temperature and the heat loss, as the corrected body temperature.

7 . The wearable device of claim 1 , wherein at least one of the first temperature sensor and the second temperature sensor is a resistance temperature detector, a thermistor, or a thermocouple.

8 . The wearable device of claim 1 , wherein the processor is further configured to calculate the heat loss due to the ambient temperature based on a difference between the reference temperature corresponding to one of a plurality of reference body locations, and the ambient temperature corresponding to the other reference body location.

9 . The wearable device of claim 1 , wherein the first temperature sensor is an infrared temperature sensor and the second temperature sensor is a thermistor, and

the processor is further configured to correct the body temperature by subtracting from the body temperature, a heat loss due to radiation from a body surface to a surrounding environment.

10 . The wearable device of claim 1 , wherein the processor is further configured to control a continuous measurement by the first temperature sensor and the second temperature sensor, and automatically obtain the body temperature continuously based on the first temperature and the second temperature.

11 . A method of controlling a wearable device, the method comprising:

controlling a first temperature sensor located at a first position of the wearable device to measure a first temperature;

controlling a second temperature sensor located at a second position of the wearable device to measure a second temperature;

controlling a third temperature sensor located at a third position of the wearable device, to measure a third temperature, wherein the second temperature sensor is disposed between the first temperature sensor and the third temperature sensor in a thickness direction of the wearable device, wherein the first temperature sensor, the second temperature sensor, and the third temperature sensor are arranged in a straight line in the thickness direction, and wherein a first thermally conductive material is provided between the first temperature sensor and the second temperature sensor, a second thermally conductive material is provided between the second temperature sensor and the third temperature sensor, and a third thermally conductive material is provided between the third temperature sensor and an inner surface of a main body case of the wearable device;

calculating an ambient temperature by

calculating a heat transfer coefficient by dividing a sum of a resistance of the third thermally conductive material and a resistance of the main body case by a resistance of the second thermally conductive material, and

subtracting, from the third temperature, a product of the heat transfer coefficient and a difference between the second temperature and the third temperature;

calculating a heat loss between two reference body points based on difference between a reference core temperature and the ambient temperature; and

obtaining a body temperature by correcting the first temperature based on the heat loss.

12 . The method of claim 11 , wherein the first temperature sensor is mounted on the main body case of the wearable device, and the second temperature sensor is mounted under a display of the wearable device.

13 . The method of claim 11 , wherein either the first position or the second position is at a printed circuit board on which a processor of the wearable device is mounted.

14 . The method of claim 11 , further comprising:

estimating a first body temperature by inputting the first temperature to a body temperature estimation model; and

obtaining a second body temperature based on the first body temperature and the heat loss, as the corrected body temperature.

15 . The method of claim 11 , wherein at least one of the first temperature sensor and the second temperature sensor is a resistance temperature detector, a thermistor, or a thermocouple.

16 . The method of claim 11 , further comprising:

calculating the heat loss due to the ambient temperature based on a difference between the reference temperature corresponding to one of a plurality of reference body locations, and the ambient temperature corresponding to the other reference body location.

17 . The method of claim 11 , wherein the first temperature sensor is an infrared temperature sensor and the second temperature sensor is a thermistor,

wherein the method further comprises:

correcting the body temperature by subtracting from the body temperature, a heat loss due to radiation from a body surface to a surrounding environment.

18 . The method of claim 11 , further comprises:

controlling the first temperature sensor and the second temperature sensor to continuously measure the first temperature sensor and the second temperature sensor; and

automatically obtaining the body temperature continuously based on the first temperature and the second temperature.