WO2004079316A1

WO2004079316A1 - Non-invasive electronic thermometer

Info

Publication number: WO2004079316A1
Application number: PCT/FR2004/000203
Authority: WO
Inventors: Benoît LINGLIN; Bénédicte SIMOND
Original assignee: Seb S.A.
Priority date: 2003-02-04
Filing date: 2004-01-29
Publication date: 2004-09-16
Also published as: FR2850754A1; FR2850754B1

Abstract

The invention relates to a non-invasive electronic thermometer for measuring body temperature by contact with a region of the skin (9), comprising a housing at the end of which a temperature probe (3) with a temperature sensor (20) is arranged and said housing comprises electronic processing means, connected to said sensor (20), for transformation of the signals received from the sensor (20) into values of the human body temperature and for display thereof. According to the invention, said temperature probe (3) comprises two separate heating elements (15,16), a first heating element (15) for heating the region of the skin (9) and a second heating element (16) for pre-heating the sensor (20) on taking a reading.

Description

NON-INVASIVE ELECTRONIC THERMOMETER

The present invention relates to a device for measuring body temperature of the non-invasive electronic thermometer type using a temperature sensor in direct contact with an area of skin of the human body whose temperature is to be known. The invention also relates to a method of manufacturing such a thermometer.

The devices most often used to measure the internal temperature are alcohol, mercury or gallium glass thermometers, thermometers which however have the disadvantage of requiring a fairly long time for stabilization of the measurement and therefore for reading the temperature. .

Another category of thermometers are the ear thermometers, in particular with infrared sensor. In this case, the measurement is faster than with analog mercury, alcohol or gallium thermometers, but the value of the temperature measured depends largely on the conditions of measurement and use of the thermometer, especially how position the sensor in front of the eardrum, the measurement being therefore too variable and not very faithful.

Furthermore, document US Pat. No. 4,487,208 describes an electronic thermometer comprising a rectal, buccal or axillary probe, a tubular probe, one end of which includes the electrical connections and means of attachment to the housing, while the opposite end ends in a plate. metal arranged transversely to the longitudinal axis of the probe and supporting the sensor. The sensor is a thermistor fixed inside the probe on the metal plate intended to come into direct contact with the tissues of the human body. One of the main drawbacks of devices of this type is that they are invasive instruments, difficult for patients to bear and capable of causing injury. To remedy these drawbacks, a non-invasive electronic thermometer which measures body temperature by contact with the skin has been proposed in document WO 02/31457 in the name of the applicant. This thermometer comprises a housing at the end of which is arranged a temperature sensor mounted on an electrically insulating ceramic support, the housing containing electronic processing means communicating with the sensor to transform the signals received from the latter into temperature values of the human body and display them. According to this document, the support comprises at least one peripheral cavity which sealingly surrounds the sensor when the latter is brought into contact with the skin. Thus, the temperature sensor is applied to the temple, being isolated from the outside environment, which gradually cancels the temperature gradient existing between the temperature sensor and the brain and allows the sensor to read the internal temperature of the human body. Operating satisfactorily, we still noticed that it had a fairly long response time, the preliminary heating of the sensor did not improve this response time satisfactorily. In addition, this sensor has also proven to be difficult to industrialize, because it used fragile components and small sizes.

A solution has been proposed in document EP 0 399 061 where the measurement probe has a flat surface intended for contact with the skin comprising a central temperature sensor surrounded by a peripheral heating element. The central sensor is enclosed in a mass of resin and is then fixed, by means of successive layered layers forming thermal insulator and elastic pressure element, to a rigid housing enclosing the connection cables, the heating element being glued to a rigid support of the same case. In another variant, the sensor and heating element assembly are included in a mass of resin. When the apparatus is started up, the initial surface temperature of the skin is first measured as a function of which the operation of the heating element is controlled, in particular its temperature and its duration. The final temperature of the human body is measured after the expiration of the preset heating time, when it is considered that the temperature difference between the surface of the skin and that internal to the body human is canceled. The response time of such a device is certainly improved, but it nevertheless remains important especially if the temperature of the ambient medium is low, several successive operations of control and command of the heating being necessary. In addition, such a construction with stage elements of such a measurement probe proves to be complex and difficult to industrialize.

The object of the present invention is to remedy these drawbacks at least in part and to provide a non-invasive electronic thermometer with low thermal inertia, capable of accurately and quickly measuring the central temperature or the internal layers of the human body.

Another object of the invention is an electronic thermometer which is easy to use, practical and harmless, while being very reliable in operation.

A further object of the invention is an electronic thermometer of simplified construction, which is easy to industrialize at lower costs.

These aims are achieved with a non-invasive electronic thermometer for measuring body temperature by contact with a skin area comprising a housing at the end of which is arranged a temperature probe comprising a temperature sensor, housing containing electronic processing means communicating with said sensor to transform the signals received from the sensor into values of the temperature of the human body and display them, since said temperature probe comprises two separate heating elements, a first heating element being intended to heat the skin area and a second heating element being intended to preheat the sensor when taking the measurement.

A non-invasive thermometer is intended for use by contact with the skin of the human body. However, it is known that the temperature of the periphery of the organism varies easily, for example between 20 and 40 ° C, for a healthy subject, whose internal temperature remains around 36 - 37 ° C. The temperature of the skin surface is practically that of the surrounding environment. It has been established that by isolating part of this skin surface from the surrounding environment, we manage, over time, to cancel the temperature difference between the inside of the body and the outside, the temperature of which will reach, in a fairly long time, the temperature of the inner layers.

According to the invention, the temperature probe comprises heating elements for both the skin and the sensor, which already makes it possible to isolate from the ambient medium, by heating with the first heating element, a skin area on which will be effected. the measurement, as well as preheating the temperature sensor before applying the probe to the skin, or even during application to the skin, thus significantly improving the response time of the sensor, while isolating it from the ambient environment during measurement. This is particularly advantageous when the temperature of the ambient medium is very low, in particular below 18 ° C., since the temperature probe is heated before its application to the skin, it continues to be so even when it is applied to the skin of so as to simultaneously bring the surface of the skin and the sensor to around the internal temperature of a subject without fever which is approximately 36-37 ° C.

The use of separate heating elements for heating the skin and that of the sensor allows a supply, or even a specific regulation of each heating element, allowing them to operate according to their own parameters, while ensuring command and / or control. simultaneous of the two heating elements by the thermometer processing electronics.

In addition, this allows a simplification of the operation of known electronic thermometers where only the skin area around the sensor was heated while the sensor, initially at room temperature, had to carry out several successive measurements, once brought into contact with the skin, in order to adjust the temperature and the heating time of the heating element according to the initial and successive readings of the temperature. It was surprisingly found that the simultaneous heating of the measured skin area and the sensor, at the same temperature or at fairly close temperatures, quickly made it possible to stabilize the temperature gradient existing between the measured skin area and the layers internal bodies of the human body, in an interval of time much shorter than that necessary within the framework of a heating sensor placed in an insulating enclosure. Indeed, the use of two separate heating elements in the context of a temperature probe operating in contact with the skin not only makes it possible to stop the heat flow towards the skin, but also allows an increase in the temperature of the sensor and that of the measured skin area, approaching that of the inner layers of the human body. This was more particularly noted during the measurement with a probe placed on the temple of a user where the temporal bone is thin and the balance is more easily established. Good results were also obtained during frontal measurements, with suitable sensors.

An applied temperature probe already heated on the skin also provides a pleasant sensation when in contact with the latter, which is sometimes advantageous when taking a temperature in children, who are often reluctant to do so.

Advantageously, the first heating element surrounds the second heating element by being situated at the periphery of the measurement probe, the second heating element being located, itself, at the center of the temperature probe.

One could, of course, have envisaged a sensor arrangement on one side of the probe and an adjacent arrangement of the heating element. However, it is preferred to arrange the sensor with its heating element in the center of an area delimited at its periphery by the first heating element. Thus, the first heating element, arranged at the periphery of the measurement probe, forms a thermal barrier all around the sensor, allowing the delimited area to be isolated from the outside environment. Such an arrangement makes it possible to significantly reduce the radial flow of heat allowing the area thus isolated to reach faster the temperature of the inner layers. This zone delimited by the first peripheral heating element can be constituted by any closed contour, a circular shape being however preferred.

Preferably, at least the second heating element is regulated at a set temperature of approximately 36 ° C as long as the set temperature is not reached. Beyond this set temperature the second heating element is definitively switched off.

The temperature of a healthy subject, without fever, being about 36-37 ° C, the sensor must be heated to a temperature close to or lower so as not to influence the results of measurement of a person's temperature without fever. One could, of course, envisage regulating the two heating elements around this temperature, but for constructive and operational simplifications, it is preferable to regulate the heating element of the sensor which, for its part, must not exceed the limit temperature d a subject without fever. The dimensioning of the heating of the other heating element was made so that this peripheral heating does not influence the temperature of the center of the zone to be measured.

It has been found, during tests carried out in the laboratory, that a peripheral arrangement of a first heating element with respect to a second central, the two operating at similar temperatures, makes it possible to effectively reduce the radial flow of heat by direction of the skin and more quickly establish the balance between the internal temperature and that of the skin in the area delimited by two heating elements. Thus, a sensor placed in the center of this zone manages to measure very quickly the value of the internal temperature of the human body.

Advantageously, the first heating element is supplied continuously when the measurement is taken.

This continuous supply of the heating element provides insulation permanent measurement area, which allows, on the one hand, to obtain a rapid rise in temperature for any initial temperature of the skin and, on the other hand, to have effective insulation during all the measurement , thus avoiding heat leaks on the periphery due, for example, to poor contact of the temperature probe with the skin.

Usefully, the electrical power of the first heating element is between 0.01 and 0.5 W.

Such a heating element operating continuously in contact with the skin must have a predetermined electrical power so as not to burn the skin, while ensuring effective insulation of the measurement area.

Preferably, the temperature probe comprises a substantially flat measuring head supporting the sensor mounted on the internal face of an electrically insulating support.

Thus, the sensor is mounted on the internal face of a substantially flat measuring head comprising a sensor mounted on an electrically insulating support, the opposite face of this support being intended to be applied to the skin. Such an electrically insulating support must ensure good electrical insulation and must, preferably, be thin for reasons of bulk and low thermal inertia. Such a support can advantageously be a polyester film. In addition, a substantially flat, even slightly curved measuring head allows good contact with the skin area to which it is applied.

Advantageously, the electrically insulating support is made of a flexible material. The internal face of this electrically insulating support carries the temperature sensor, while its external face is intended to come into contact with the skin. Such a flexible support thus ensures good adaptation to the reliefs of the skin allowing good positioning of the measuring head on the skin. In an advantageous variant embodiment of the invention, said sensor is a thermistor. It is preferred to use a CTN type ceramic sensor which has the advantage of being precise and inexpensive, while having small dimensions and being able to be easily applied to various substrates. This automates manufacturing and reduces costs.

Advantageously, the first heating element and the second heating element are arranged in the same plane of the measuring head, on the internal face of the electrically insulating support, being separated by a layer of electrical insulation from the sensor.

Thus, the two peripheral and central heating elements are deposited on the same electrically insulating and flat support. This same electrically insulating support carrying, on its internal face, the sensor it is then necessary to separate it from the heating elements by a layer of electrical insulator. Such a construction makes it possible to use a single electrically insulating support thus facilitating the construction of the measuring head which thus has low thermal inertia and a small size.

Preferably, the first heating element and the second heating element are resistive tracks deposited on the electrically insulating support.

These heating elements can thus be deposited easily and automatically on a common electrically insulating support, which optimizes the manufacturing cost. Such resistive tracks can be obtained by depositing resistive paste by any engraving or printing technique, for example by screen printing.

Advantageously, the measurement head is circular in diameter proportional to the measurement depth.

A circular measuring head is best suited for contact with the skin, especially the temple area. In addition, such a circular shape heated on the periphery by the first heating element determines, by its shape and dimensions, a measurement area isolated from the outside environment. It has been established that the value of the measuring depth is directly proportional to the diameter of the measuring head. Such a diameter / depth of measurement ratio has advantageously been established at 2: 1.

Preferably, the first heating element is annular with a predetermined width.

During laboratory tests, it turned out that for a predetermined width of an annular heating element, the radial flow of heat towards the skin could be stopped and that equilibrium was quickly established in the area of measurement delimited by the peripheral annular heating element. Such a width depends on the diameter of the measuring head, or even on the outside diameter of the peripheral heating element. Thus, for example, for a measuring head with a diameter between 30 and 60 mm, the minimum width to ensure good insulation is 3 to 10 mm.

Usefully, the temperature probe is bordered by a projecting flexible peripheral lip surrounding the end portion of the probe intended for contact with the skin.

Such a prominent flexible peripheral lip is thus the first to bear on the skin when taking the measurement, thus ensuring, by its deformation, a good adaptation around the measurement point, while closing inside, around the head. for measuring the temperature probe, an air pocket serving as thermal insulation. This lip can deform axially and / or radially to avoid thermal leaks and allow the temperature probe to be well arranged in the plane of the skin.

The invention also relates to a method of manufacturing a temperature probe for a non-invasive electronic thermometer, method comprising the following steps: - depositing the conductive supply tracks on an electrically insulating support;

- depositing two resistive tracks forming separate heating elements on said electrically insulating support comprising the conductive tracks; - the deposition of a layer of electrical insulator covering at least partially the previous deposits;

- the cutting of said electrically insulating support in order to obtain a so-called measurement part comprising said deposits connected to a connection part;

- the shaping of said measurement part in order to obtain a fixing flange;

- The transfer of a temperature sensor on the layer of electrical insulator of said measurement part;

- mounting of said measurement part with said fixing flange in a rigid support so that it has a front part oriented towards a measurement zone;

- thermal insulation of the rear part of said measurement part contained in said rigid body.

The invention will be better understood from the study of the embodiments taken without any limitation being implied and illustrated in the appended figures in which:

- Figure 1 is a side view of an electronic thermometer of the invention;

- Figure 2 is a sectional view of a temperature probe of the thermometer of the invention when taking a measurement;

- Figures 3a to 3i illustrate the succession of main steps for producing a measurement head for a temperature probe of the thermometer of the invention;

- Figure 4a shows a perspective view of a temperature probe of the thermometer of the invention and Figure 4b shows a partial perspective view of the electronic part of the thermometer of the invention; - Figure 5 is an axial sectional view of the temperature probe illustrated in Figure 4a.

FIG. 1 illustrates an electronic thermometer 1 of the invention comprising a housing 2 intended to be held in the hand and the upper end of which comprises a temperature probe 3 comprising a measuring head 10 intended to be applied to an area of skin to perform a temperature measurement. The box 2 contains: an electronic processing card 5 and its connections, a display device 8, as well as supply batteries 7.

FIG. 2 illustrates a temperature probe 3 where the measuring head 10 is applied to a skin area 9 to take a measurement. The temperature probe 3 comprises a tubular body 27 at the end of which the measurement head is fixed 10. The measurement head 10 comprises an electrically insulating support 12 produced for example from a polyester film whose external face is applied to the skin , while on its internal face, in the center of the measuring head 10, is fixed a temperature sensor 20.

The measurement head 10 is preferably flexible, which allows it to better adapt to any measurement area on the surface of an individual's body. The measuring head 10 is fixed and supported by a rigid tubular body 27 ensuring good mechanical strength of the assembly. The electrical components of the measuring head 10 are connected to the electronic circuit of the thermometer 1 by connections 4 which project outside the tubular body 27. The measuring head 10 is isolated from the outside environment by a cover 30 made of thermally material insulator, for example a polyurethane foam, placed inside the tubular body 27, behind the measuring head 10.

More particularly according to the invention, the temperature probe 3 comprises means allowing preheating of the measurement zone delimited on the skin 9 by the measurement head 10, as well as of the temperature sensor 20, before and during the measurement. , as will be explained later. These preheating means comprise a first heating element 15 deposited on the internal face of the electrically insulating support 12, on the periphery of the measuring head 10 and a second central heating element 16 also deposited on the internal face of the electrically insulating support 12, but in correspondence with sensor 20. The first heating element 15 and the second heating element 16 are advantageously produced in the form of flat heating elements deposited on the electrically insulating support 12. The first heating element 15 has an annular shape and is deposited over the entire periphery, or most of it , of the measuring head 10 so as to delimit, in relation to the skin, a measuring zone. The outside diameter of the first heating element 15 is chosen as a function of the type of measurement carried out, for example as a function of the depth of the internal layers relative to the skin area where the measuring head 10 is applied, while its width is calculated so that equilibrium with the inner layers is quickly acquired for a given operating temperature. Advantageously according to the invention, the first heating element 15 is made to operate continuously during the measurement and it thus plays the role of thermal barrier with respect to the external environment. Its operating temperature is around 36 °. For example, the outside diameter of the first heating element can be between 30 and 60 mm, for a width between 3 and 10 mm.

The second heating element 16 is, for its part, deposited in the center of the measuring head 10, in relation to the sensor 20. Its shape and its dimensions are close to those of the sensor 20, so as to ensure a faster warming up of the sensor 20. As an example, the sensor 20 is a CTN type ceramic pellet of cylindrical shape deposited in the center of the measuring head 10. The second heating element 16 can in this case have a square or circular shape so as to that the sensor 10 is included inside the surface of the second heating element. For example, such a heating element can have a surface of between 3 and 30 mm ² .

The second heating element 16 serves to preheat the sensor 20 to a temperature set point temperature of about 36 ° C which is lower than the theoretical temperature of the brain of a healthy subject without fever. The second heating element is supplied only when the temperature measured by the sensor 20 is lower than this set temperature. As soon as the setpoint temperature of the second heating element 16 is reached, its electrical supply is cut off to allow the measurement zone delimited by the periphery of the measurement head 10 to reach temperature equilibrium with the brain.

An advantageous method of manufacturing a measuring head 10 will be described with reference to FIGS. 3a to 3i. Thus, in FIG. 3a, there is a sheet of electrically insulating film, for example a polyester film of MYLAR type with a thickness of 125 microns used to form the electrically insulating support 12. On the electrically insulating support 12 tracks will first be deposited. conductive 14, as visible in FIG. 3a, by a screen printing of paste comprising silver particles in a polymer base. The conductive tracks 14 are six in number being provided to ensure the connections of the first heating element 15, the second element 16 and the sensor 20 with the electronic control part and with the power supply provided inside the housing 2 of the thermometer. This deposition by screen printing of the conductive tracks 14 then undergoes cooking between 80 ° C. and 120 ° C.

FIG. 3c shows the next step which consists in depositing resistive tracks which will form the first heating element 15 and the second heating element 16, these resistive tracks being connected to the respective conductive tracks 14. These resistive tracks are preferably deposited by screen printing of a polymer-based paste and comprising silver and / or carbon inclusions. The thickness of the resistive track deposit is approximately 12 microns for a dry deposit. This step is then followed, like the previous one, by baking between 80 ° C and 120 ° C.

The conductive tracks and the resistive tracks deposited on the electrically insulating support 12 are then partially covered by a layer 18 of electrically insulating material, as shown in FIG. 3d. This material can be a polymer-based climate varnish with a thickness of 10 to 30 microns which polymerizes with UV. Layer 18 covers most of the surface of the previous deposits, however leaving one end of the conductive tracks 14, as well as the connection terminals 19 of the sensor 20. This deposition of layer 18 of insulation is followed by UV drying.

Figures 3e and 3f show the cutting and respectively the separation of the cut part with respect to the initial sheet of insulating film. This cutting makes it possible to obtain a circular part 23, comprising the heating elements 15, 16 as well as part of the conductive tracks 14, circular part extended by a tongue 24 comprising the continuation of the conductive tracks 14.

FIG. 3g shows a step of shaping the previously cut part, making it possible to obtain, for example by stamping, a flange 22 on the periphery of the circular part 23. Thanks to this stamping, the measuring head 10 is found prominent relative to the tubular body 27 to be sure that it comes first into contact with the skin during application. Above all, the slope and the depth of the rim 22 determine the elasticity of the measuring head 10 with respect to the housing, which is flexible enough to adapt to the peculiarities of the skin, but rigid enough to expel any air bubble at the interface.

In a variant, it is possible to envisage a complementary stamping in order to obtain a measuring head 10 having a contact surface with the skin of slightly convex shape, capable of better adapting to the hollow regions of the skin, for example on the temple of the skin. 'a baby.

In FIG. 3h is shown the step of transferring the sensor 20 by bonding, with a silver-based paste, to the connection terminals 19 located at the center of the circular part 23 of the measuring head 10.

The step presented in FIG. 3i consists in bending the tab 24 at 90 ° so that the end conductive tracks 14 form a part of vertical connection with the rest of the components of the device.

The measuring head 10 thus produced is then fixed, by gluing, with the face external of its rim 22 on the internal face of the end 28 of the tubular body 27. An insulating cover 30 then covers the rear part of the measuring head 10 thus isolating it from the outside environment. This assembly forms the temperature probe 3, better visible in FIGS. 4a and 5, a probe which has connections 4 engaging with a connection part 6 of the electronic card 5, as visible in FIG. 4b.

In operation, the user switches on the device, which controls the supply of the heating elements 15 and 16, a waiting message being visible on the screen of the display 8. As soon as the second heating element 16 has reached its set temperature, the user is informed by an audible and / or light signal that he can take the temperature. The user then applies the measuring head 10 of the thermometer to the skin area where he wants to take the measurement, advantageously on the temple. Once in contact with the skin, the measuring head 10 continues to supply the first heating element 15 in order to isolate a measurement zone on the skin which it heats on its periphery. The second heating element 16 can optionally also be supplied at this time if the temperature measured by the sensor 20 has dropped below the set temperature, due to contact with the skin. This is best shown in Figure 2, where the arrows in solid lines show the flow of heat from the first heating element, and the arrows in dashed lines represent a flow of heat regulated at its set temperature, from the second element heater 16. As soon as this set temperature (around 36 ° C) is reached, the electronic card 5 controls the stopping of the supply of the second heating element 16.

At this time, the device waits until the thermal equilibrium is established between the internal layers, in particular the brain, and the area of skin measured. The electronic card measures the signal received at the terminals of the sensor 20 at regular time intervals, for example every second, and, once this equilibrium is reached, that is to say once the received signal is stable, the electronic card controls the display of the measured temperature value, possibly announced by an audible signal. The user can then read the value of the body temperature which corresponds to that of the inner layers of the human body.

Other variants and embodiments of the invention can be envisaged, without departing from the scope of its claims.

Thus, instead of the sensor 20 which is a CTN effect ceramic, one could use a PTC effect ceramic or one or more thermistors obtained for example by screen printing, metal deposition, by etching, etc., or even any other type of sensor whose we know the law of temperature variation over time. One could also consider attaching a radiometer antenna to the insulating layer 18 located on the internal face of the measuring head 10, the radiation emitted by the skin being transformed by the antenna into signals which can then be processed by electronic treatment inside the housing 2 of the thermometer. An infrared sensor could also be oriented towards the internal face of the measuring head 10 in order to measure, at a distance, the radiation emitted by the skin.

Any other type of insulating support can be used, for example a polyimide or polyethylene support, provided that it is a good electrical insulator, that it has low thermal inertia, as well as good flexibility.

Claims

1. Non-invasive electronic thermometer (1) for measuring the body temperature by contact with a skin area (9) comprising a housing (2) at the end of which is arranged a temperature probe (3) comprising a temperature sensor ( 20), housing containing electronic processing means communicating with said sensor (20) to transform the signals received from the sensor (20) into values of the temperature of the human body and display them, characterized in that said temperature probe (3 ) has two separate heating elements (15,16), a first heating element (15) being intended to heat the skin area (9) and a second heating element (16) being intended to preheat the sensor (20) during the taking measurements.

2. Thermometer according to claim 1, characterized in that the first heating element (15) surrounds the second heating element (16) being located on the periphery of the measurement probe, the second heating element being located in the center of the temperature probe (3).

3. Thermometer according to one of the preceding claims, characterized in that at least the second heating element (16) is regulated to a set temperature of approximately 36 ° C.

4. Thermometer according to one of the preceding claims, characterized in that the first heating element (15) is continuously supplied during the measurement.

5. Thermometer according to claim 4, characterized in that the electric power of the first heating element (15) is between 0.01 and 0.5W.

6. Thermometer according to one of the preceding claims, characterized in that the temperature probe (3) comprises a substantially flat measuring head (10) supporting the sensor (20) mounted on the internal face of an electrically insulating support (12).

7. Thermometer according to claim 6, characterized in that the insulating support (12) is made of a flexible material.

8. Thermometer according to one of claims 6 or 7, characterized in that said sensor (20) is a thermistor.

9. Thermometer according to one of claims 6 to 8, characterized in that the first heating element (15) and the second heating element (16) are arranged in the same plane of the measuring head (10), on the face internal of the electrically insulating support (12), being separated by a layer of electrical insulator (18) from the sensor (20).

10. Thermometer according to claim 9, characterized in that the first heating element (15) and the second heating element (16) are resistive tracks deposited on the electrically insulating support (12).

11. Thermometer according to one of claims 6 to 10, characterized in that the measuring head (10) is circular in diameter proportional to the measurement depth.

12. Thermometer according to one of the preceding claims, characterized in that the first heating element (15) is annular with a predetermined width.

13. Thermometer according to one of the preceding claims, characterized in that the temperature probe (3) is bordered by a projecting flexible peripheral lip surrounding the end portion of the probe intended for contact with the skin.

14. Method for manufacturing a temperature probe for a non-invasive electronic thermometer, characterized in that it comprises the following steps:

- depositing the conductive supply tracks on an electrically insulating support;

- depositing two resistive tracks forming separate heating elements on said electrically insulating support comprising the conductive tracks;

- the deposition of a layer of electrical insulator covering at least partially the previous deposits; - the cutting of said electrically insulating support in order to obtain a so-called measurement part comprising said deposits connected to a connection part;

- the shaping of said measurement part in order to obtain a fixing flange;