Electronic device and method of measuring air temperature using the same
An electronic device may include: a main body including a first surface and a second surface; a first temperature sensor and a second temperature sensor which are provided inside the main body, wherein the second temperature sensor is disposed closer to the surface of the main body than the first temperature sensor; and a processor, which while the second surface of the main body is in contact with a body part of a user, is configured to estimate a heat flux that is generated by body heat, of the user based on a difference between a first temperature measured by the first temperature sensor and a second temperature measured by the second temperature sensor, and measure air temperature based on the estimated heat flux and the second temperature.
1 . An electronic device comprising:
a main body comprising a first surface and a second surface;
a first temperature sensor and a second temperature sensor which are provided inside the main body, wherein the second temperature sensor is disposed closer to the first surface of the main body than the first temperature sensor;
a first thermally conductive material disposed on the first temperature sensor, to face the second temperature sensor, with a gap between the first thermally conductive material and the second temperature sensor;
a second thermally conductive material disposed on the second temperature sensor to face the first surface of the main body, with a gap between the second thermally conductive material and the first surface; and
a processor, which while the second surface of the main body is in contact with a body part of a user, is configured to;
estimate a heat flux that is generated by body heat of the user, based on a difference between a first temperature measured by the first temperature sensor and a second temperature measured by the second temperature sensor;
compute a correction coefficient based on a resistance value of the first thermally conductive material, a resistance value of the second thermally conductive material, and a resistance value of the first surface of the main body;
obtain a corrected heat flux by applying the correction coefficient to the estimated heat flux; and
measure air temperature based on the corrected heat flux and the second temperature.
2 . The electronic device of claim 1 , wherein the processor is further configured to measure the air temperature by linearly combining the corrected heat flux and the second temperature.
3 . The electronic device of claim 1 , wherein:
a first thermally conductive material is directly disposed-on the first temperature sensor; and
a second thermally conductive material is directly disposed on the second temperature sensor.
4 . The electronic device of claim 3 , wherein the processor is further configured to compute the correction coefficient based on a ratio between the resistance value of the first thermally conductive material and a sum of the resistance value of the second thermally conductive material and the resistance value of the first surface of the main body.
5 . The electronic device of claim 1 , wherein at least one of the first temperature sensor and the second temperature sensor is a thermistor.
6 . The electronic device of claim 1 , wherein the first temperature sensor is disposed at a vertical distance of 10 mm or less from the second surface between the main body and the body part of the user.
7 . The electronic device of claim 1 , wherein the second temperature sensor is disposed at a vertical distance of 10 mm or less below the first surface of the main body.
8 . The electronic device of claim 1 , wherein a distance between the first temperature sensor and the second temperature sensor is in a range of 1 mm to 50 mm.
9 . A method of estimating air temperature by using an electronic device that comprises a first temperature sensor and a second temperature sensor which are provided inside a main body of the electronic device, wherein the second temperature sensor is disposed closer to a first surface of the main body than the first temperature sensor, the method comprising:
measuring a first temperature by using the first temperature sensor when the main body is in contact with a user;
measuring a second temperature by using the second temperature sensor when the main body is in contact with the user;
estimating a heat flux that is generated by body heat of the user, based on a difference between the first temperature and the second temperature;
computing a correction coefficient based on a resistance value of a first thermally conductive material disposed on the first temperature sensor, to face the second temperature sensor, with a gap between the first thermally conductive material and the second temperature sensor, a resistance value of a second thermally conductive material disposed on the second temperature sensor to face the first surface of the main body, with a gap between the second thermally conductive material and the first surface;
obtaining a corrected heat flux by applying the correction coefficient to the estimated heat flux; and
measuring the air temperature based on the corrected heat flux and the second temperature.
10 . The method of claim 9 , wherein the measuring of the air temperature comprises measuring the air temperature by linearly combining the corrected heat flux and the second temperature.
11 . The method of claim 9 , wherein the measuring of the air temperature comprises computing the correction coefficient based on a ratio between the resistance value of the first thermally conductive material and a sum of the resistance value of the second thermally conductive material and the resistance value of the first surface of the main body.
12 . The electronic device of claim 1 , further comprising:
a third temperature sensor disposed closer to the first surface of the main body than the second temperature sensor,
wherein the processor is configured to estimate the corrected heat flux as a first heat flux, estimate a second heat flux based on a difference between the second temperature and a third temperature measured by the third temperature sensor, measure the air temperature based on the first heat flux, and the second heat flux, and the third temperature.
13 . The electronic device of claim 12 , further comprising:
a third thermally conductive material directly disposed on the third temperature sensor to face the first surface of the main body, with a gap between the third thermally conductive material and the first surface,
wherein the processor is further configured to compute the air temperature based on the resistance value of the first thermally conductive material, the resistance value of the second thermally conductive material, and a resistance value of the third thermally conductive material, the first heat flux, the second heat flux, and the third temperature.
14 . The electronic device of claim 12 , wherein the second temperature sensor is attached to an electrical component in the main body, and is further configured to measure a temperature of heat generated from the electrical component.
15 . The electronic device of claim 14 , wherein the heat generated from the electrical component is estimated based on a difference between the first heat flux and the second heat flux.
16 . The electronic device of claim 12 , wherein at least one of the first temperature sensor, the second temperature sensor, and the third temperature sensor is a thermistor.
17 . A smart watch comprising:
a main body comprising a first surface and a second surface;
a strap connected to both ends of the main body;
a first temperature sensor and a second temperature sensor which are provided inside the main body;
a first thermally conductive material disposed on the first temperature sensor, to face the second temperature sensor, with a gap between the first thermally conductive material and the second temperature sensor;
a second thermally conductive material disposed on the second temperature sensor to face the first surface of the main body, with a gap between the second thermally conductive material and the first surface; and
a processor, which while the strap is wrapped around a wrist of a user such that the main body is worn on the wrist, is configured to;
estimate a heat flux that is generated by body heat of the user, based on a difference between a first temperature measured by the first temperature sensor and a second temperature measured by the second temperature sensor;
compute a correction coefficient based on a resistance value of the first thermally conductive material, a resistance value of the second thermally conductive material, and a resistance value of the first surface of the main body;
obtain a corrected heat flux by applying the correction coefficient to the estimated heat flux; and to
measure air temperature based on the corrected heat flux and the second temperature.
18 . The smart watch of claim 17 , wherein the processor is further configured to measure the air temperature by linearly combining the corrected heat flux and the second temperature.
19 . The smart watch of claim 18 , wherein the first thermally conductive material is directly disposed on the first temperature sensor; and
the second thermally conductive material is directly disposed on the second temperature sensor.