Body temperature determination system

Abstract

Body Temperature Determination System. The present invention relates to a system for remotely determining a person's body temperature (Tbody). This system comprises: a first infrared temperature sensor arranged to measure at least one skin temperature (Tz) of the person over a measurement area of ​​the person, this skin temperature value (Tz) optionally being correctable based on a distance value representative of the distance between the first sensor and the person; and a processing unit arranged to determine a body temperature (Tbody) value from the skin temperature (Tz) and a deviation value associated with the skin temperature measurement area. Figure for the abstract: Fig. 5

Description

Title of the invention: System for determining body temperature

[0001] The present invention relates to a remote temperature measurement system.

[0002] The detection of potential COVID 19 patients is currently carried out by taking temperature, additional clinical examinations, then by a COVID 19 test which still has a relatively low level of confidence.

[0003] There is a significant need to be able to rapidly detect, in particular using mobile means, potential patients with contagious diseases, for example the disease linked to COVID 19.

[0004] Temperature measurements that are as reliable as possible are crucial for such disease detections.

[0005] The invention thus relates to a remote temperature measurement system, arranged to measure a temperature on a person, in particular on at least one area of ​​the person's face, this system comprising:

[0006] - a first temperature sensor operating in the infrared and arranged to measure at least one skin temperature of the person, in particular on at least one area of ​​the person's face, this first sensor being in particular an infrared camera, the skin temperature measured by this first sensor being called (Shot),

[0007] - a second temperature sensor arranged to measure a temperature ambient,

[0008] - a processing unit arranged for:

[0009] - determine an intermediate skin temperature (Tbb) as a function of at least the temperature measured (Tir) by the first temperature sensor, a distance value representative of the distance between the first sensor and the person, and the ambient temperature measured by the second sensor, and

[0010] - determine a corrected skin temperature value (Ts) as a function of at least the intermediate skin temperature (Tbb) and a correction linked to the emissivity of the person's skin.

[0011] The invention makes it possible in particular to obtain the most precise skin temperature possible, which is not or only slightly affected by the parameters of distance and ambient temperature. Other parameters in addition to distance and ambient temperature can be taken into account, as will be seen later.

[0012] The intermediate skin temperature value (Tbb) is not calculated with consideration of the emissivity of the skin. The emissivity is taken into account in determining the final corrected temperature (Ts), as will be seen later.

[0013] According to one aspect of the invention, the system comprises a distance measuring apparatus for providing the distance value.

[0014] Alternatively, this distance value may be a predetermined value. For example, this distance value is set in advance based on the location of the chair where the person who is subject to the temperature measurement sits, this value being for example set at 1 meter.

[0015] According to one aspect of the invention, the processing unit is arranged to determine the corrected skin temperature value (Ts) from a single intermediate skin temperature value (Tbb).

[0016] According to one aspect of the invention, this system comprises a distance measuring device arranged to measure the distance between the person's face and the first temperature sensor.

[0017] According to one aspect of the invention, this distance measurement is based for example on an area of ​​the person's face, for example on the area of ​​the face where the first temperature sensor measures the skin temperature (Tir).

[0018] According to one aspect of the invention, this device is chosen from a stereoscopic measuring device, a radar, a Time of Flight (TOF) Sensor type device, an inertial balance which in particular makes it possible to position the person's body on a virtual reference checkerboard.

[0019] According to one aspect of the invention, the distance measurement can also be carried out by image processing by measuring a gap between the eyes on the image and then determining, from this estimated gap, the distance between the face on which the temperature is measured and the first temperature sensor.

[0020] According to one aspect of the invention, the processing unit is arranged to determine the corrected skin temperature value (Ts) from a plurality of intermediate skin temperature values ​​(Tbb).

[0021] According to one aspect of the invention, the processing unit is arranged to use the same distance value to determine all intermediate skin temperature values ​​(Tbb).

[0022] This may prove sufficient, namely to use the same distance value, when the distance between the person and the first sensor is sufficiently large, for example at least 1 meter.

[0023] Alternatively, the processing unit is arranged to use several distance values ​​to determine the intermediate skin temperature values ​​(Tbb).

[0024] In particular, each calculation of the intermediate skin temperature value (Tbb) uses an associated distance value.

[0025] Each distance value corresponds to a point on the person's face. This point is a point where the temperature measurement by the first sensor is made.

[0026] According to one aspect of the invention, the first temperature sensor is arranged to measure the temperatures at a plurality of points on the person's face.

[0027] This plurality of points notably forms a mask of measurement points placed on the person's face.

[0028] The distance measurement at each temperature measurement point allows for better accuracy of the intermediate skin temperature (Tbb) values.

[0029] This is particularly advantageous when the first temperature sensor is placed relatively close to the person's face, for example at a distance of a few tens of centimeters. Over these short distances, the accuracy of the distance value between the temperature measuring point and the first sensor has a significant influence on the accuracy of the intermediate skin temperature value (Tbb).

[0030] For example, the intermediate temperature (Tbb) on the tip of the nose must be corrected with a distance value measured on the tip of the nose. Indeed, when the first sensor is relatively close to the face, a distance measured on the tip of the nose and the distance measured on another point of the face, for example on the cheekbone, can differ greatly, in proportion.

[0031] In the case of measurements of several distance values ​​on the face, the system may comprise a measuring device for determining the distance at a plurality of points on the person's face, this device being chosen for example from a stereoscopic measuring device or a device of the Time of Flight (TOF) Sensor type.

[0032] This camera operates on the principle of time of flight (TOF) which allows a 3-dimensional (3D) scene to be measured in real time. This type of camera is known.

[0033] On the other hand, when the first sensor is placed sufficiently far from the person, for example more than 70 cm, it is possible to use the same distance value to correct the values ​​taken by the first sensor, in order to determine the different intermediate temperature values ​​(Tbb). The variations in distance at the different measurement points on the face remain relatively small and do not significantly affect the accuracy of the corrected temperature values.

[0034] According to one aspect of the invention, it comprises a camera, in particular a Red Green Blue camera, or RGB camera, arranged to define on the person's face the remarkable temperature measurement point, or the remarkable temperature measurement points, for the first sensor. In particular, this camera operates in the visible range.

[0035] The first and / or second temperature sensor comprises a component for measuring the temperature in a housing of the sensor and / or a sensitive element thereof sensor.

[0036] For example, if the temperature measured by this sensor is outside a predetermined temperature range for which the sensor is calibrated, the system considers the first and / or the second temperature sensor as unreliable, and does not take into account the data resulting from it.

[0037] According to one aspect of the invention, the correction linked to the emissivity of the person's skin is chosen to be dependent on the intermediate skin temperature (Tbb).

[0038] According to one aspect of the invention, the corrected skin temperature value is given by a curve with the intermediate skin temperature on the abscissa and the corrected skin temperature on the ordinate, taking into account the emissivity of the skin.

[0039] The dependence of skin emissivity on skin temperature is contained in this curve.

[0040] This curve is obtained for example using real measurements.

[0041] In an exemplary embodiment of the invention, the system does not need to explicitly access a skin emissivity value. The system uses the aforementioned curve which contains the influence of the emissivity on the measurement of the temperature of the region concerned, in particular the face. The correction linked to the emissivity is contained in this curve.

[0042] According to one aspect of the invention, the correction linked to the emissivity of the person's skin is chosen to also depend on the person's perspiration and makeup.

[0043] According to one aspect of the invention, the intermediate skin temperature (Tbb) is equal to a polynomial function, for example of order 2, of the temperature measured (Tir) by the first temperature sensor, of a distance value representative of the distance between the first sensor and the person, and the ambient temperature measured by the second sensor.

[0044] According to one aspect of the invention, it comprises a light intensity sensor, in particular a thermopile type sensor comprising thermocouples and arranged to convert thermal energy into electrical energy.

[0045] According to one aspect of the invention, the processing unit is connected to this light intensity sensor, in particular of the thermopile type, and is arranged to use light intensity data provided by this sensor to correct the temperature (Tbb).

[0046] This thermopile type sensor thus measures the parasitic incident infrared flux.

[0047] The correction for ambient brightness can integrate this light intensity data divided by a radiant thermal power value associated with the person's basal metabolism.

[0048] According to one aspect of the invention, the first temperature sensor is a camera operating in the infrared, preferably at a wavelength between 7 and 14 micrometers.

[0049] According to one aspect of the invention, this camera is of the digital type.

[0050] According to one aspect of the invention, the entire system is of the digital type, without analog component.

[0051] According to one aspect of the invention, the second temperature sensor arranged to measure an ambient temperature is a sensor comprising a platinum-based sensitive element, in particular of the PT 100 type.

[0052] The invention also relates to a method for measuring temperature remotely, for measuring a temperature on a person, in particular on at least one area of ​​the person's face, this method comprising the following steps:

[0053] - providing a first temperature sensor operating in the infrared and arranged to measuring at least one skin temperature of the person, in particular on at least one area of ​​the person's face, this first sensor being in particular an infrared camera, the skin temperature measured by this first sensor being called (Tir),

[0054] - providing a second temperature sensor arranged to measure a temperature ambient,

[0055] - determine an intermediate skin temperature (Tbb) as a function of at least the temperature measured (Tir) by the first temperature sensor, a distance value representative of the distance between the first sensor and the person, and the ambient temperature measured by the second sensor, and

[0056] - determine a corrected skin temperature value (Ts) as a function of at least the intermediate skin temperature (Tbb) and a correction linked to the emissivity of the person's skin.

[0057] According to one aspect of the invention, the remarkable temperature measurement point(s) are geometrically defined by means of an image area called a Building box, which surrounds it, for example by means of the geometric mean of the sides of the image area. This image area is a surface delimited by a series of points which is constructed by an object identification algorithm.

[0058] The system can be packaged in a transportable box and can be placed in a building, for example an airport, a hospital or any other location.

[0059] The invention can serve as an aid for providing diagnostic information, in particular for the detection of a disease in a person, in particular a contagious disease such as COVID 19.

[0060] The invention also relates, independently or in connection with the above, to a system for remotely determining a person's body temperature, this system comprising: - a first temperature sensor operating in the infrared and arranged for measuring at least one skin temperature (Tz) of the person on a measurement area of ​​the person, this skin temperature value (Tz) possibly being able to be corrected according to a distance value representative of the distance between the first sensor and the person, - a processing unit arranged to determine a body temperature value from the skin temperature and a deviation value associated with the skin temperature measurement area.

[0061] This temperature value (Tz), if corrected for distance, can be the temperature (Ts) described above.

[0062] This temperature (Tz) used to calculate the body temperature may, as a variant, not be corrected according to the distance, and be a value directly taken from the first sensor.

[0063] According to the invention, body temperature is an internal temperature of the person's body. This body temperature is important to know in particular so that a medical diagnosis can be made reliably. For example, this body temperature must be able to be measured reliably to determine whether or not a person has a fever. This body temperature can in particular be measured by taking a rectal temperature.

[0064] The invention makes it possible to obtain a reliable body temperature remotely, without having to use a thermometer which must be placed in contact with the person's body.

[0065] Body temperature is generally recorded at 37.2°.

[0066] The invention thus makes it possible to limit contact with the patient, which is important, for example, to avoid the transmission of viral disease.

[0067] The invention makes it possible to correct a skin temperature value in order to obtain a reliable body temperature. The temperature measured on the skin is generally lower than the body temperature, for example that measured by a rectal or oral method.

[0068] According to one aspect of the invention, the temperature deviation value is added to the measured skin temperature. In other words, these two values ​​are two terms of a linear relationship.

[0069] According to one aspect of the invention, the deviation value is a fixed predetermined value.

[0070] In other words, this deviation value is not dependent on the measured skin temperature.

[0071] This deviation value is determined in advance, for example by statistical analysis on a group of people, of the deviations between measured skin temperature values ​​and body temperature. This retained deviation value is for example an average value of the calculated differences between the skin temperatures on the area associated with the body temperature of the people in the sample. This calculation can be done, for example, by artificial intelligence.

[0072] According to one aspect of the invention, the deviation value (Delta) is chosen from a list of values ​​classified according to one or more parameters chosen from: the age of a person, the gender of a person, the presence of a disease such as diabetes, the phenotype of a person, an outside temperature, a humidity level, the time of day.

[0073] These parameters can be provided by sensors or by responses provided by a person.

[0074] This makes it possible to place the correction made in a specific context of the measurement, and thus obtain a more precise correction.

[0075] According to one aspect of the invention, the system is arranged to measure a plurality of temperatures over a plurality of measurement zones.

[0076] According to one aspect of the invention, the first sensor is arranged to measure a plurality of temperatures on a plurality of measurement zones (or measurement points), for example on 366 points of the person's face.

[0077] According to one aspect of the invention, the processing unit is arranged to determine a body temperature value from the plurality of skin temperatures each corrected with a deviation value associated with the measurement area.

[0078] According to one aspect of the invention, each corrected temperature term with its associated deviation value is assigned a weighting coefficient to obtain the body temperature.

[0079] Thus the body temperature obtained is a weighted sum of temperature values ​​measured on several areas of the person's body.

[0080] According to one aspect of the invention, the relationship for obtaining body temperature is written:

[0081] Tbody= (Tz(l) + Delta(l))*Alpha(l)+ (Tz(2) + Delta(2))*Alpha(2)+...+ (Tz(i) + Delta(i))*Alpha(i) ) + .. .+(Tz(N) + Delta(N))*Alpha(N) where N is the total number of zones on which the skin temperature is measured, Delta(i) is the deviation value associated with the zone of index i, Alpha(i) is the weighting coefficient for the zone of index i, with the sum of Alpha (i) = 1 for i varying from 1 to N.

[0082] According to one aspect of the invention, the weighting coefficient Alpha(i) is fixed, predetermined in advance.

[0083] Alternatively, the weighting coefficient Alpha(i) chosen from a list of values ​​classified according to one or more parameters chosen from: the age of a person, the gender of a person, the presence of a disease such as diabetes, the phenotype of a person, an outside temperature, a humidity level, the time of day.

[0084] According to one aspect of the invention, the weighting coefficients are determined using artificial intelligence.

[0085] For example, these weighting coefficients are obtained using statistical data.

[0086] For example, the relative weight associated with the measurement area which is a corner of the eye is greater than 25%. It is understood that the temperature measured on the corner of the eye has a relatively significant weight in this case.

[0087] It has been found that the highest skin temperature is often that measured at one corner of the eye.

[0088] The deviation values ​​and the weighting coefficients are stored in a table stored in a memory of the system.

[0089] The invention also relates to a method for remotely determining a body temperature of a person, this method comprising the following steps: - providing a first temperature sensor operating in the infrared and arranged to measure at least one skin temperature (Tz) of the person on a measurement zone of the person, this skin temperature value (Tz) possibly being able to be corrected as a function of a distance value representative of the distance between the first sensor and the person, - determine a body temperature value from the skin temperature and a deviation value associated with the skin temperature measurement area.

[0090] According to one aspect of the invention, the measurement zones are chosen from several of the following zones: a lip, a cheek, a forehead, a corner of the eye, the nose, a cheekbone, a mouth, an ear, a hand, or over the entirety of a mesh constructed on the surface of the face.

[0091] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures:

[0092] [Fig.l] schematically illustrates a system according to a non-limiting embodiment of the invention.

[0093] [Fig.2] schematically illustrates a system according to another non-limiting embodiment of the invention,

[0094] [Fig.3] illustrates notable measurement points on a person's face, using the system according to the invention,

[0095] [Fig.4] shows a curve illustrating the influence of emissivity on temperature measurements,

[0096] [Fig.5] shows temperature zones on a human body,

[0097] [Fig.6] shows a table with the deviation and weighting values ​​for calculating body temperature.

[0098] [Fig.l] shows a remote temperature measurement system 100, arranged to measure a temperature on a person, here on the person's face.

[0099] This system 100 comprises a first temperature sensor 1 operating in the infrared and arranged to measure a skin temperature of the person, on areas or points of the person's face.

[0100] The first temperature sensor 1 is a camera operating in the infrared, for example between 7 and 14 micrometers.

[0101] The skin temperature measured by this first sensor 1 is called Tir,

[0102] This system 100 further comprises a second temperature sensor 2 arranged to measure an ambient temperature Tamb.

[0103] The second temperature sensor 2 arranged to measure an ambient temperature is a sensor comprising a platinum-based sensitive element, in particular of the PT 100 type.

[0104] This system 100 comprises a processing unit 3 arranged for:

[0105] - determine an intermediate skin temperature Tbb as a function of at least the temperature measured by the first temperature sensor 1, of a distance value Dist representative of the distance between the first sensor 1 and the person, and the ambient temperature Tamb measured by the second sensor 2, and

[0106] - determine a corrected skin temperature value Ts as a function of at least the intermediate skin temperature Tbb and a correction linked to the emissivity of the person's skin.

[0107] The system 100 comprises a distance measuring apparatus 5 for providing the distance value Dist.

[0108] Alternatively, this distance value Dist may be a predetermined value. For example, this distance value is set in advance based on the location of the chair where the person who is subject to the temperature measurement sits, this value being for example set at 1 meter.

[0109] In the exemplary embodiment of [Fig. 1], the processing unit 3 is arranged to determine the corrected skin temperature value Ts from a single intermediate skin temperature value Tbb.

[0110] The distance measuring apparatus 5 is arranged to measure the distance between the person's face and the first temperature sensor 1.

[0111] This distance measurement is based for example on an area of ​​the person's face, for example on the area of ​​the face where the first temperature sensor 1 measures the skin temperature Tir.

[0112] This distance measuring device 5 is chosen from a stereoscopic measuring device, a radar, a Time of Flight (TOF) Sensor type device, an inertial balance.

[0113] The distance measurement can also be carried out by image processing by measuring a distance between the eyes on the image and then determining, from this estimated distance, the distance between the face on which the temperature is measured and the first temperature sensor.

[0114] In the exemplary embodiment of [Fig.2], the processing unit 100 is arranged to determine the corrected skin temperature value Ts from a plurality of intermediate skin temperature values ​​Tbb.

[0115] In a first embodiment, the processing unit 3 is arranged to use the same distance value Dist to determine all the intermediate skin temperature values ​​Tbb.

[0116] This may prove sufficient, namely to use the same distance value, when the distance between the person and the first sensor 1 is sufficiently large, for example at least 1 meter.

[0117] When the first sensor is placed sufficiently far from the person, it is possible to use the same distance value to correct the values ​​taken by the first sensor, in order to determine the different intermediate temperature values ​​(Tbb). The variations in distance at the different measurement points on the face remain relatively small and do not significantly affect the accuracy of the corrected temperature values.

[0118] In another embodiment, the processing unit 3 is arranged to use several distance values ​​Dist to determine the intermediate skin temperature values ​​Tbb.

[0119] In particular, each calculation of the intermediate skin temperature value Tbb uses an associated distance value Dist.

[0120] Each distance value Dist corresponds to a point on the person's face. This point is a point where the temperature measurement by the first sensor 1 is made.

[0121] The first temperature sensor 1 is thus arranged to measure the temperatures at a plurality of points on the person's face. This plurality of points notably forms a mask 20 of measurement points superimposed on the person's face 21, as can be seen in [Fig.3].

[0122] The distance measurement at each temperature measurement point allows for better accuracy of the intermediate skin temperature values ​​Tbb. This is particularly advantageous when the first temperature sensor 1 is placed relatively close to the person's face 21, for example at a distance of a few tens of centimeters. Over these short distances, the accuracy of the distance value between the temperature measurement point and the first sensor 1 has a significant influence on the accuracy of the intermediate skin temperature value Tbb. For example, the intermediate temperature Tbb at the tip of the nose must be corrected with a distance value measured on the tip of the nose. Indeed, when the first sensor is relatively close to the face, a distance measured on the tip of the nose and the distance measured on another point of the face, for example on the cheekbone, can differ greatly, in proportion.

[0123] The number of points on the point mask 20 may be greater than 100, or even greater than 200.

[0124] This number of points of the mask is, in the example described, equal to 366 points.

[0125] To measure this multitude of distance values ​​Dist, the measuring device distance is chosen from a stereoscopic measuring device or a Time of Flight (TOF) Sensor type device.

[0126] This camera operates on the principle of time of flight (TOF) which allows a 3-dimensional (3D) scene to be measured in real time. This type of camera is known.

[0127] The system 100 comprises a Red Green Blue camera 8, or RGB camera, arranged to define on the face 21 of the person the remarkable temperature measurement point, or the remarkable temperature measurement points, for the first sensor 1. This is step 40 of figures 1 and 2.

[0128] The notable temperature measurement points are defined geometrically by means of an image area called Building box, which surrounds it, for example by means of the geometric mean of the sides of the image area. This image area is a surface delimited by a series of points which is constructed by an object identification algorithm.

[0129] This camera 8 operates in the visible range.

[0130] After step 40, the infrared camera 1 carries out the temperature measurements on these points of the mask 20 (step 41) to obtain the different measured temperature values ​​Tir.

[0131] The first and / or the second temperature sensor may comprise a component for measuring the temperature in a housing of the sensor and / or a sensitive element of this sensor.

[0132] For example, if the temperature measured by this sensor is outside a predetermined temperature range for which the sensor is calibrated, the system considers the first and / or the second temperature sensor as unreliable, and does not take into account the data resulting from it.

[0133] The correction linked to the emissivity of the person's skin is chosen to be dependent on the intermediate skin temperature Tbb.

[0134] The corrected skin temperature value Ts is given by a curve 30 (see [Fig.4]) with the intermediate skin temperature Tbb on the abscissa and the corrected skin temperature Ts on the ordinate, taking into account the emissivity of the skin.

[0135] The dependence of the skin emissivity on the skin temperature is contained in this curve 30.

[0136] In the example described, it is of polynomial form of order 2.

[0137] This curve is obtained for example using real measurements.

[0138] The system does not need to explicitly access a skin emissivity value. The system uses the aforementioned curve which contains the influence of the emissivity on the measurement of the temperature of the region concerned, in particular the face. The correction linked to the emissivity is contained in this curve 30.

[0139] The correction linked to the emissivity of the person's skin can, if desired, be chosen depending also on the person's perspiration and makeup.

[0140] The intermediate skin temperature Tbb is equal to a polynomial function, here of order 2, of the temperature measured Tir by the first temperature sensor 1, of a distance value Dist representative of the distance between the first sensor 1 and the face 21 of the person, and the ambient temperature Tamb measured by the second sensor 2.

[0141] In the example described, the intermediate skin temperature is given by the following equation:

[0142] Tbb=a0+al.Tir+a2.Dist+a3.Tamb+a4.Tir2+a5.Dist2+a6.Tamb2+a7.Tair.Dist

[0143] +a8.Tir.Tamb+a9.Dist.Tamb

[0144] Where aO, al ... a9 are predetermined coefficients of the polynomial.

[0145] The system 100 comprises a light intensity sensor 9, here a thermopile type sensor comprising thermocouples and arranged to convert thermal energy into electrical energy.

[0146] The processing unit 3 is connected to this light intensity sensor 9, in particular of the thermopile type, and is arranged to use light intensity data provided by this sensor to correct Tbb.

[0147] The correction for ambient brightness can integrate this radiant light intensity data divided by a radiant thermal power value associated with the person's basal metabolism.

[0148] For example, this correction due to ambient brightness is a corrective term proportional to the ratio between the radiant light intensity and a radiant thermal power value associated with the person's basal metabolism.

[0149] This coefficient of proportionality is for example between 0.1 and 10.

[0150] This value of radiant thermal power associated with basal metabolism is for example taken equal to 14 W.m2 (Watt per unit of surface).

[0151] In addition to the proportionality described above, it is possible, if desired, to impose this correction due to the ambient brightness as being equal to zero when the ambient radiant brightness is less than 10% of the radiant thermal power associated with basal metabolism.

[0152] The entire system 100 is of the digital type, without analog components.

[0153] In the example of [Fig.l], only one measured temperature value Tir is used to obtain the correction. The Tir value taken into account is the highest Tir temperature on the point mask. This step of selecting the highest Tir value is done in step 42 of [Fig.l].

[0154] The temperature point retained is for example a point close to the eye.

[0155] Step 43 aims to determine an intermediate skin temperature Tbb as a function of the measured temperature Tir retained, of a distance value Dist representative of the distance between the first sensor and the person, and the ambient temperature Tamb measured by the second sensor.

[0156] Step 43 uses the aforementioned polynomial function.

[0157] In step 44, a corrected skin temperature value Ts is determined as a function of the intermediate skin temperature Tbb and a correction linked to the emissivity of the person's skin, as explained above.

[0158] In the example of [Fig.2], all the temperature values ​​Tir measured in step 41 are used to determine as many intermediate temperatures Tbb. It is step 47 of [Fig.2] where 366 intermediate temperature values ​​Tbb are obtained using the aforementioned polynomial equation.

[0159] In step 48, all these Tbb values ​​are corrected with the emissivity correction.

[0160] In step 49, the highest corrected value Ts is retained.

[0161] We will now describe a system for remotely determining a person's body temperature Tbody.

[0162] This system can be formed by the system 100 described previously, which comprises: - the first temperature sensor 1 operating in the infrared and arranged to measure at least one skin temperature Tz of the person on a measurement zone of the person, - the processing unit 3 arranged to determine a body temperature value Tbody from the skin temperature Tz and a predetermined deviation value Delta associated with the skin temperature measurement zone.

[0163] In the example described, this temperature value Tz is corrected according to the distance and is taken as the temperature Ts described above.

[0164] In a variant not illustrated, this temperature Tz used to calculate the body temperature may, as a variant, not be corrected according to the distance, and be a value directly taken from the first sensor.

[0165] Body temperature Tbody is an internal temperature of the person's body 50, as illustrated in [Fig.5].

[0166] This body temperature Tbody is important to know, in particular so that a medical diagnosis can be made reliably. For example, this body temperature must be able to be measured reliably to determine whether or not a person has a fever. This body temperature can be measured, in particular, by taking a rectal temperature.

[0167] Body temperature is generally recorded at 37.2°.

[0168] The invention makes it possible to correct a skin temperature value in order to obtain a reliable body temperature. The temperature measured on the skin is generally lower than the body temperature, for example that measured by a rectal or oral method.

[0169] The deviation value Delta(i) is a fixed predetermined value.

[0170] In other words, this deviation value is not dependent on the measured skin temperature.

[0171] This deviation value is determined in advance, for example by statistical analysis on a group of people, of the deviations between measured skin temperature values ​​and the body temperature. This retained deviation value is for example an average value of the calculated differences between the skin temperatures on the associated area and the body temperature of the people in the sample. This calculation can be done, for example, by artificial intelligence.

[0172] The system 100 is arranged to measure a plurality of temperatures over a plurality of measurement zones.

[0173] The processing unit 3 is arranged to determine a body temperature value from the plurality of skin temperatures Tz(i) each corrected with a predetermined deviation value Delta(i) associated with the measurement zone.

[0174] In the present invention, the relationship for obtaining body temperature is written:

[0175] Tbody= (Tz( 1) + Delta(l))*Alpha(l)+ (Tz(2) + Delta(2))*Alpha(2)+...+ (Tz(i) + Delta(i))*Alpha(i) + ...+(Tz(N) + Delta(N))*Alpha(N) where N is the total number of zones on which the skin temperature is measured, Delta(i) is the deviation value associated with the zone of index i, Alpha(i) is the weighting coefficient for the zone of index i, with the sum of Alpha (i) = 1 for i varying from 1 to N.

[0176] The weighting coefficients are determined using artificial intelligence.

[0177] For example, these weighting coefficients are obtained using statistical data.

[0178] The measurement areas are chosen from several of the following areas: a lip, a cheek, a forehead, a corner of the eye, the nose, a cheekbone, a mouth, an ear, a hand or on the whole of a mesh constructed on the surface of the face.

[0179] For example, the Delta(i) and Alpha(i) values ​​are given in the table in [Fig.6].

[0180] It has been found that the highest skin temperature is often that measured at one corner of the eye.

[0181] The deviation values ​​and the weighting coefficients are stored in a table stored in a memory of the system.

[0182] .

Claims

Claims

1. System (100) for remotely determining a body temperature (Tbody) of a person, this system comprising: - a first temperature sensor (1) operating in the infrared and arranged to measure at least one skin temperature (Tz) of the person on a measurement zone of the person, this value of the skin temperature (Tz) possibly being able to be corrected as a function of a distance value representative of the distance between the first sensor and the person, - a processing unit (3) arranged to: • determine a body temperature value (Tbody) from the skin temperature (Tz) and a deviation value (Delta) associated with the skin temperature measurement zone, in which the processing unit (3) is arranged to determine a body temperature value from a plurality of skin temperatures each corrected with a deviation value associated with the measurement zone,and in which each temperature term (Tz(i)) corrected with its associated deviation value is assigned a weighting coefficient (Alpha(i)) to obtain the body temperature (Tbody).,

2. System according to the preceding claim, in which the temperature deviation value (Delta) and the measured skin temperature are two terms of a linear relationship.

3. System according to one of the preceding claims, in which the deviation value (Delta) is a fixed predetermined value.

4. System according to one of the preceding claims, in which the deviation value (Delta) is determined in advance, by statistical analysis on a group of people, of the deviations between measured skin temperature values ​​and body temperature.

5. System according to one of the preceding claims, in which the system (100) is arranged to measure a plurality of temperatures on a plurality of measurement zones (Tz(i)).

6. System according to claim 1 or 2, in which the deviation value (Delta) is chosen from a list of values ​​classified according to one or several parameters chosen from: a person's age, a person's gender, the presence of a disease such as diabetes, a person's phenotype, an outside temperature, a humidity level, the time of day.

7. System according to one of the preceding claims, in which the body temperature (Tbody) obtained is a weighted sum of temperature values ​​measured on several areas of the person's body.

8. System according to the preceding claim, in which the relationship for obtaining the body temperature is written: Tbody = (Tz(l) + Delta(l))*Alpha(l) + (Tz(2) + Delta(2))*Alpha(2) +...+ (Tz(i) + Delta(i))*Alpha(i) ) + ...+(Tz(N) + Delta(N))*Alpha(N) where N is the total number of zones on which the skin temperature is measured, Delta(i) is the deviation value associated with the zone of index i, Alpha(i) is a weighting coefficient for the zone of index i, with the sum of Alpha (i) = 1 for i varying from 1 to N.

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