Temperature measuring device, temperature measuring method, and temperature attenuation measuring method

Abstract

The present invention provides a temperature measuring device, a temperature measuring method, and a temperature attenuation measuring method, which are capable of measuring the temperature of a measured object with high precision, high accuracy, and high-speed responsiveness, and can maintain the temperature of a thin-film temperature-sensing element for measurement at a lower temperature than the temperature of the measured object. The temperature measuring device includes: a temperature sensing portion for detecting temperature; a thin-film temperature-sensing element for measurement, which can measure the temperature by bringing the temperature sensing portion into contact with the measured object; a protective heating thin-film temperature-sensing element, which is arranged to exchange heat with the thin-film temperature-sensing element for measurement via a heat insulating layer and is controlled to have a temperature equal to that of the thin-film temperature-sensing element for measurement; a temperature control element, which can set the thin-film temperature-sensing element for measurement to a temperature state that is a fixed temperature lower than the temperature of the measured object; and a control processing portion, which controls the thin-film temperature-sensing element for measurement, the protective heating thin-film temperature-sensing element, and the temperature control element.

Description

Technical Field

[0001] The present invention relates to a temperature measuring device, a temperature measuring method and a temperature attenuation measuring method. Background Art

[0002] In the industrial and medical fields, it is desired to measure the surface temperature of an object with high precision, high accuracy, and high-speed responsiveness.

[0003] For example, in the medical field, diagnosis of suspected skin malignancies begins with external observation and palpation, followed by excision of a portion of the affected area for pathological evaluation. Skin cancers, such as melanoma (malignant melanoma), have a high cure rate when discovered in the early stages, but the survival rate becomes extremely low once the disease progresses. Diagnosis often involves visual examination using a dermatoscope, but this requires expertise.

[0004] Specifically, when skin malignancies are suspected, pathological examinations are performed through skin biopsies. However, these procedures are invasive and require time to determine the results. Furthermore, actinic keratosis, an intraepidermal cancer, can progress to squamous cell carcinoma over time, potentially metastasizing to multiple organs, necessitating screening. Therefore, there is a desire for non-invasive skin cancer diagnostic methods that can facilitate early detection and treatment.

[0005] Under these circumstances, a temperature measurement device capable of non-invasive skin cancer diagnosis has been proposed (see Patent Document 1). The temperature measurement device shown in Patent Document 1 heats the protective heat source sensor to a temperature equal to that of the temperature measurement sensor. This equalizes the surface temperature of the object being measured, the temperature of the temperature measurement sensor, and the protective heat source sensor, preventing heat from transferring from the temperature measurement sensor to the protective heat source sensor, and also preventing heat from transferring from the surface of the object being measured to the temperature measurement sensor. Consequently, the temperature measurement sensor can measure temperature with high precision and accuracy. Furthermore, the temperature measurement device shown in Patent Document 1 measures the thermal conductivity of the affected area by applying a constant pulse of heat to the measurement sensor.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-217885

[0009] Patent Document 2: Japanese Patent Application Laid-Open No. 2006-300765

[0010] Patent Document 3: Japanese Patent No. 5327840

[0011] Non-patent literature

[0012] Non-Patent Document 1: First-in-human clinical study of novel technique to diagnose malignant melanoma via thermal conductivity measurements, T. Okabe, T. Fujimura, J. Okajima, Y. Kambayashi, S. Aiba, S. Maruyama, Scientific Reports, Vol. 9, (2019)

[0013] Non-Patent Document 2: Non-invasive measurement of effective thermal conductivity of human skin with a guard-heated thermistor probe, T. Okabe, T. Fujimura, J. Okajima, S. Aiba, S. Maruyama, International Journal of Heat and Mass Transfer, Vol. 126, (2018)

[0014] Non-Patent Document 3: Development of a guard-heated thermistor probe for the accurate measurement of surface temperature, T. Okabe, J. Okajima, A. Komiya, S. Maruyama, International Journal of Heat and Mass Transfer, Vol. 108, (2017) Summary of the Invention

[0015] Problems to be solved by the invention

[0016] However, the temperature measurement sensor and protective heat source sensor described in Patent Document 1 are glass-enclosed negative temperature coefficient (NTC) thermistors. These have large heat capacity and limited temperature responsiveness, making high-speed responsiveness difficult to expect. Furthermore, in principle, the relationship between the surface temperature of the object being measured and the ambient temperature must be such that the ambient temperature, i.e., the temperature of the temperature measurement sensor, is lower than the surface temperature of the object being measured.

[0017] An embodiment of the present invention aims to provide a temperature measuring device, a temperature measuring method, and a temperature attenuation measuring method, which can measure the temperature of a measured object with high precision, high accuracy, and high-speed responsiveness, and can maintain the temperature of a thin-film temperature-sensing element for measurement at a lower temperature than the temperature of the measured object.

[0018] Technical means to solve the problem

[0019] The temperature measuring device of an embodiment of the present invention is characterized in that it includes: a temperature sensing portion for detecting temperature; a thin film temperature sensing element for measurement, which can measure the temperature by bringing the temperature sensing portion into contact with the object to be measured; a thin film temperature sensing element for protection and heating, which is arranged to be able to exchange heat with the thin film temperature sensing element for measurement via a heat insulation layer and is controlled so that its temperature becomes equal to that of the thin film temperature sensing element for measurement; a temperature control element that can set the thin film temperature sensing element for measurement to a temperature state that is a fixed temperature lower than the temperature of the object to be measured; and a control processing portion that controls the thin film temperature sensing element for measurement, the thin film temperature sensing element for protection and heating, and the temperature control element.

[0020] The temperature measuring device of this embodiment can measure the temperature of an object with high precision, high accuracy, and high-speed responsiveness, while maintaining the temperature of the thin-film temperature-sensing element lower than that of the object. While the temperature measuring device is preferably used for biological applications, it is not limited to this application. It is also applicable to measuring the surface temperature of industrial objects, and the object to be measured is not particularly limited.

[0021] The temperature measuring method of an embodiment of the present invention is characterized in that it includes: a temperature sensing portion for detecting temperature; a thin film temperature sensing element for measurement, capable of measuring temperature; a protective heating thin film temperature sensing element, arranged with an insulating layer between the thin film temperature sensing element for measurement and the thin film temperature sensing element for measurement; and a temperature control element, capable of controlling the temperature of the thin film temperature sensing element for measurement. The temperature measuring method includes the following steps: controlling the temperature setting of the thin film temperature sensing element for measurement to a temperature that is a fixed temperature lower than that of the object to be measured by the temperature control element; bringing the temperature sensing portion into contact with the object to be measured; controlling so that the temperature of the thin film temperature sensing element for measurement becomes equal to the temperature of the thin film temperature sensing element for protection and heating; and outputting the measurement result of the temperature of the object to be measured.

[0022] Moreover, the temperature decay measuring method of an embodiment of the present invention is characterized in that it includes: a temperature sensing portion for detecting temperature; a thin film temperature sensing element for measurement, capable of measuring temperature; a protective heating thin film temperature sensing element, arranged with an insulating layer separated from the thin film temperature sensing element for measurement; and a temperature control element, capable of controlling the temperature of the thin film temperature sensing element for measurement, and the temperature decay measuring method includes the following steps: bringing the temperature sensing portion into contact with the measured object; applying a first heat pulse of fixed power to the thin film temperature sensing element for measurement; detecting the temperature decay characteristics of the thin film temperature sensing element for measurement at a fixed time after the application of the first heat pulse stops; applying a second heat pulse of fixed power with a time width longer than the first heat pulse to the thin film temperature sensing element for measurement; and detecting the temperature decay characteristics of the thin film temperature sensing element for measurement at a fixed time after the application of the second heat pulse stops.

[0023] The temperature decay measurement method of this embodiment can detect the temperature decay characteristics from the epidermis to the dermis of a living being and calculate the thermal conductivity, thereby enabling non-invasive diagnosis of an affected area.

[0024] Effects of the Invention

[0025] According to an embodiment of the present invention, a temperature measuring device, a temperature measuring method, and a temperature attenuation measuring method can be provided, which can measure the temperature of a measured object with high precision, high accuracy, and high-speed responsiveness, and can maintain the temperature of a thin-film temperature-sensing element used for measurement at a lower temperature than the temperature of the measured object. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a longitudinal sectional view showing a temperature measuring device according to a first embodiment of the present invention.

[0027] Figure 2 (a) is in Figure 1 The cross-section along line AA in the figure is as follows: Figure 2 (b) is in Figure 1The cross-section along line BB in the figure is as follows: Figure 2 (c) is in Figure 1 Cross-section along line CC.

[0028] Figure 3 It is a cross-sectional view showing a thin film temperature sensing element.

[0029] Figure 4 This is a wiring diagram showing the basic connection status of a thin-film temperature sensing element.

[0030] Figure 5 This is a block diagram showing the structure of a temperature measuring device.

[0031] Figure 6 It is an explanatory diagram showing an application example of the temperature measuring device.

[0032] Figure 7 This is a flowchart showing an overview of temperature measurement.

[0033] Figure 8 This is a time chart showing a map of heat pulse generation in temperature decay measurement.

[0034] Figure 9 This is a flowchart showing an overview of temperature decay measurement.

[0035] Figure 10 It is an explanatory diagram schematically showing a temperature measuring device according to a second embodiment of the present invention.

[0036] [Explanation of Symbols]

[0037] 1: Thin film temperature sensing element for measurement

[0038] 2: Protective heating film temperature sensing element

[0039] 3: Temperature control element

[0040] 4: Outline

[0041] 5: Control processing unit

[0042] 6: Pen-shaped stand

[0043] 11: Substrate

[0044] 12: Conductive layer

[0045] 13: Thin film component layer

[0046] 14: Protective insulation layer

[0047] 12a: Electrode part

[0048] 12b: Wire

[0049] 15, 25: Thermal insulation spacers

[0050] 31: Radiator

[0051] 32: Thin film temperature sensing element for temperature control element

[0052] 33: Heat sink fins

[0053] 34: Insulating partition wall

[0054] 41: Temperature sensing part

[0055] 51: CPU

[0056] 52: ROM

[0057] 53: RAM

[0058] 54: Input / output control components

[0059] 55: Power supply circuit

[0060] 61: Coil spring

[0061] 62: Wire

[0062] Ct: catheter

[0063] S1, S2: thermal insulation layer DETAILED DESCRIPTION

[0064] [First embodiment]

[0065] Below, refer to Figures 1 to 6 A temperature measuring device according to a first embodiment of the present invention will be described. Figure 1 as well as Figure 2 (a) to Figure 2 (c) is a longitudinal sectional view and a transverse sectional view schematically showing a temperature measuring device, Figure 3 This is a cross-sectional view of a thin film temperature sensing element. Figure 4 This is a wiring diagram showing the basic connection status of a thin film temperature sensing element. Figure 5 This is a block diagram showing a temperature measuring device. Figure 6 These are explanatory diagrams showing examples of application of a temperature measuring device. In each figure, the scale of each component may be appropriately altered to make it recognizable. Identical or corresponding parts are denoted by the same reference numerals, and duplicate descriptions are omitted.

[0066] The temperature measurement device of this embodiment is configured to be appropriately incorporated into a catheter, thereby being able to measure the temperature of a living being as a measured object with high precision, high accuracy, and high-speed responsiveness. Figure 1 The temperature measuring device 10 is shown in a state where it is installed in the front end portion of the catheter Ct. Figure 2(a) is the cross-sectional view along line AA. Figure 2 (b) is a cross-sectional view along line BB. Figure 2 (c) is a cross-sectional view along the CC line. Figure 1 as well as Figure 2 (a) to Figure 2 In (c), the wiring relationship of the conductors etc. is omitted.

[0067] like Figure 1 as well as Figure 2 (a) to Figure 2 As shown in (c), the temperature measuring device 10 includes a thin film temperature sensing element 1 for measurement, a thin film temperature sensing element 2 for protection heating, a temperature control element 3, a tubular outer shell 4 for accommodating these components, and a control processing unit 5 for controlling the components (see Figure 5 ).

[0068] In this embodiment, the outer shell 4 is the tubular shaft of the catheter Ct. This shaft is elongated, has a lumen, and exhibits appropriate rigidity and flexibility. A hollow guidewire is disposed within the lumen along its longitudinal direction. The shaft can be constructed from synthetic resins such as polyurethane, polyolefin, polyamide, and polyether polyamide. The shaft has an outer diameter of 8 French or less and a length of 900 mm to 1100 mm.

[0069] Therefore, the thin film temperature sensing element 1 for measurement, the thin film temperature sensing element 2 for protection and heating, and the temperature control unit 3 are housed in the front end portion of the catheter Ct as the outer shell 4. The front end portion of the catheter Ct serves as a temperature sensing unit 41 for detecting temperature and functions as a probe.

[0070] The thin film temperature sensing element 1 for measurement has basically the same specifications and characteristics as the protective heating thin film temperature sensing element 2 described later. The thin film temperature sensing element 1 for measurement is the distal end of the shaft of the catheter Ct and is disposed in the inner diameter portion.

[0071] If you refer to Figure 3 As shown, the thin film temperature sensing element 1 for measurement is a thin film thermistor, and includes a substrate 11 , a conductive layer 12 formed on the substrate 11 , a thin film element layer 13 , and a protective insulating layer 14 .

[0072] The substrate 11 is roughly circular and fits within the inner diameter of the catheter Ct. It is made of an insulating aluminum oxide material. Alternatively, ceramics such as aluminum nitride and zirconium oxide, or semiconductors such as silicon and germanium, can be used to form the substrate 11. An insulating thin film is deposited on one side of the substrate 11 (the upper side in the figure) using a sputtering method or other method. The substrate 11 is extremely thin, with a thickness of 200 μm or less, specifically 50 μm to 200 μm, and preferably 150 μm or less.

[0073] By using such an extremely thin substrate 11 for a thin film thermistor, a temperature sensing element having a small heat capacity, high sensitivity, and excellent thermal responsiveness can be realized.

[0074] The conductive layer 12 constitutes a wiring pattern and is formed on the substrate 11. The conductive layer 12 is formed by depositing a metal thin film using a sputtering method or other method. Suitable metal materials include precious metals such as platinum (Pt), gold (Au), silver (Ag), palladium (Pd), or alloys thereof, such as Ag-Pd alloys. Furthermore, a pair of electrodes 12a are integrally formed with the conductive layer 12 at both ends of the substrate 11 and electrically connected to the conductive layer 12.

[0075] The thin film element layer 13 is a thermistor composition comprising an oxide semiconductor having a negative temperature coefficient. The thin film element layer 13 is formed on the conductive layer 12 by sputtering or other methods, thereby being electrically connected to the conductive layer 12. Alternatively, the thin film element layer 13 may comprise an oxide semiconductor having a positive temperature coefficient.

[0076] The thin-film element layer 13 includes, for example, two or more elements selected from transition metal elements such as manganese (Mn), nickel (Ni), cobalt (Co), and iron (Fe). The protective insulating layer 14 is formed so as to cover the thin-film element layer 13 and the conductive layer 12. The protective insulating layer 14 is a protective glass layer formed of borosilicate glass.

[0077] Furthermore, the metal wire 12b is joined and electrically connected to the electrode portion 12a by welding. Specifically, the wire 12b is formed of a material with low thermal conductivity, such as constantan or hastelloy (registered trademark), and its thermal conductivity is preferably 5W / m·K to 25W / m·K. They can be connected by using a welding material such as solder or by laser welding. Furthermore, the wire diameter of the wire 12b is preferably By configuring the lead wire 12b in this manner, the heat capacity and heat radiation amount of the thermistor due to the lead wire 12b can be reduced, thereby achieving high sensitivity and improving thermal responsiveness.

[0078] Alternatively, the other side of the substrate 11 (the lower side of the measured object in the figure) may be covered with a protective film. In this case, the thin film temperature sensing element 1 for measurement is in contact with the measured object via the protective film.

[0079] Alternatively, the thin film temperature sensing element 1 for measurement may be disposed in the inner diameter portion of the catheter Ct with the thin film element layer 13 disposed on the other surface of the substrate 11. In this case, the thin film element layer 13 side of the thin film temperature sensing element 1 for measurement is further covered with a protective film, and the thin film temperature sensing element 1 for measurement, specifically, the thin film element layer 13 side, is in contact with the object to be measured via the protective film.

[0080] The protective heating thin film temperature sensing element 2 is the same element as the measuring thin film temperature sensing element 1 and has the same specifications and characteristics. Therefore, the same or corresponding parts as those of the measuring thin film temperature sensing element 1 are denoted by the same or corresponding reference numerals and detailed descriptions are omitted.

[0081] Mainly as Figure 2 As shown in (c), the protective heating thin-film temperature sensing element 2 includes a thin-film element layer 23. A plurality of, specifically eight, conductive wire passage holes 21a are formed around the periphery of the substrate 21. The conductive wires of the measurement thin-film temperature sensing element 1 or the protective heating thin-film temperature sensing element 2 are inserted through these passage holes 21a and directed toward the control processing unit 5. Furthermore, the passage holes 21a are formed with line symmetry, thereby maintaining good thermal balance.

[0082] Again Figure 1 As shown, the protective heating thin-film temperature-sensing element 2 and the measuring thin-film temperature-sensing element 1 are arranged along the longitudinal direction of the conduit Ct via the heat-insulating layer S1, enabling heat exchange therebetween. Furthermore, the measuring thin-film temperature-sensing element 1 and the protective heating thin-film temperature-sensing element 2 are arranged with their thin-film element layers 13 and 23 facing each other.

[0083] The thermal insulation layer S1 is a gas layer, specifically, an air layer, maintained between the measuring thin-film temperature sensing element 1 and the protective heating thin-film temperature sensing element 2 by an annular thermal insulation spacer 15. The thermal insulation layer S1 has a thickness of 0.05 mm to 1 mm. This thickness suppresses heat transfer from the measuring thin-film temperature sensing element 1 to the protective heating thin-film temperature sensing element 2, maintaining appropriate thermal insulation performance. It also enables heat exchange between the measuring thin-film temperature sensing element 1 and the protective heating thin-film temperature sensing element 2, maintaining equal temperatures between them.

[0084] The heat insulating layer S1 is preferably an air layer, but may be a gas layer such as nitrogen or argon, and may also include a heat insulating material.

[0085] Temperature control element 3 is a thermoelectric element, specifically a Peltier element. A Peltier element utilizes the Peltier effect. When a direct current flows through it, one surface of the element becomes a heat-absorbing surface, while the other becomes a heat-dissipating surface. By reversing the direction of the current, the heat-absorbing and heat-dissipating surfaces are reversed.

[0086] The temperature control element 3 is disposed at the rear end of the measurement thin-film temperature sensing element 1 and the protective heating thin-film temperature sensing element 2. Furthermore, a heat sink 31 and a temperature control thin-film temperature sensing element 32 are disposed at the front end of the temperature control element 3, and heat dissipation fins 33 are disposed at the rear end.

[0087] If you refer to Figure 2 As shown in FIG. 5( b ), the heat sink 31 is formed into a short cylindrical shape from a metal having good thermal conductivity, such as copper, aluminum, brass, or iron, and is arranged to be thermally coupled to the surface of the Peltier element.

[0088] Furthermore, the thin-film temperature sensor 32 for the temperature control element is thermally coupled to the heat sink 31. The thin-film temperature sensor 32 for the temperature control element detects the temperature of the heat sink 31 and controls the temperature of the Peltier module including the Peltier element serving as the temperature control element 3. Therefore, the ambient temperature can be lowered by setting the heat sink 31 to a fixed temperature. Furthermore, the thin-film temperature sensor 1 for measurement can be maintained at a fixed temperature lower than the temperature of the object being measured.

[0089] Furthermore, the heat sink 31 has a plurality of, specifically four, through-holes 31a for conducting wires formed around its periphery. Furthermore, through-holes (not shown) are formed around the periphery of the substrate of the temperature control element thin-film temperature sensor 32, communicating with these through-holes 31a. Thus, for example, two conducting wires each of the measurement thin-film temperature sensor 1, the protective heating thin-film temperature sensor 2, and the temperature control thin-film temperature sensor 32 are inserted through these through-holes 31a and the through-holes in the substrate of the temperature control element thin-film temperature sensor 32, leading to the control processing unit 5. Furthermore, these through-holes are formed lineally symmetrically, similar to the through-holes 21a in the protective heating thin-film temperature sensor 2, thereby ensuring good thermal balance.

[0090] The thin film temperature sensing element 32 for temperature control has basically the same structure as the thin film temperature sensing element 1 for measurement, but the specifications and characteristics may be the same or different and can be designed and selected as appropriate.

[0091] Furthermore, a thermal insulation layer S2 is interposed between the temperature control element thin film temperature sensor 32 and the protective heating element thin film temperature sensor 2. The thermal insulation layer S2 is constructed similarly to the aforementioned thermal insulation layer S1, being an air layer. The separation between the two elements is maintained by an annular thermal insulation spacer 25 disposed between the protective heating element thin film temperature sensor 2 and the temperature control element thin film temperature sensor 32. The thickness of the thermal insulation layer S2 is set to a range of 1 mm to 3 mm, making it larger than the thickness of the thermal insulation layer S1. While the thermal insulation layer S2 is preferably an air layer, it may also be a gas layer such as nitrogen or argon, and may also contain an insulating material.

[0092] The heat dissipation fins 33 are thermally coupled and electrically connected to the temperature control element 3. Specifically, a pair of heat dissipation fins 33 are formed from a material with good thermal conductivity and electrical conductivity, such as copper or aluminum, and are formed into an elongated cylindrical shape, extending longitudinally from the temperature control element 3. Therefore, the heat dissipation fins 33 dissipate heat generated by the temperature control element 3 and also function as electrodes for the temperature control element 3.

[0093] Furthermore, an insulating partition wall 34 is provided at the center of the pair of heat dissipation fins 33 to electrically insulate the heat dissipation fins 33 which also serve as electrodes.

[0094] The temperature measuring device 10 described above is preferably formed such that the outer diameter of the outer shell 4 (the axis of the catheter Ct) is 1 mm to 2 mm.

[0095] Figure 4 This diagram shows the basic connection configuration of the thin-film temperature sensor Rth. This diagram is used to measure the temperature of the thin-film temperature sensor 1 for measurement, the thin-film temperature sensor 2 for protective heating, and the thin-film temperature sensor 32 for temperature control. The thin-film temperature sensor Rth and a fixed resistor R, serving as a limiting resistor, are connected in series to a power supply V. An output terminal is connected between the thin-film temperature sensor Rth and the fixed resistor R. The voltage at the output terminal is measured as output voltage Vout, and the temperature detected by the thin-film temperature sensor Rth is measured based on this measurement result.

[0096] Next, refer to Figure 5 The block structure of the temperature measuring device 10 will be described.

[0097] In this embodiment, the overall control is performed by executing a predetermined program by a microcomputer (hereinafter referred to as "microcomputer") as a control processing unit 5. The microcomputer generally includes a central processing unit (CPU) 51 having an operation unit and a control unit, a read-only memory (ROM) 52 and a random access memory (RAM) 53 as storage components, and an input / output control component 54. In addition, a power supply circuit 55 is connected to the input / output control component 54. In addition, a power supply circuit 55 is connected to the power supply circuit 55. Figure 4 The circuit shown.

[0098] The power circuit 55 includes the power supply V and has a function of supplying and controlling power to the thin film temperature sensing elements Rth by applying a voltage of the power supply V to each thin film temperature sensing element Rth. Furthermore, the power circuit 55 is provided with a power supply for supplying and controlling power to the temperature control element 3 .

[0099] Specifically, the power supplied from the power supply in the power supply circuit 55 is controlled by a program stored in the microcomputer's storage unit. The output voltage Vout is input to the microcomputer, processed, and fed back to the power supply circuit 55, or output as a measurement output to the measurement output unit O / P for processing. The measurement output unit O / P is a display unit or a printing unit. Furthermore, an input unit I / P is connected to the input / output control unit 54. The input unit I / P is, for example, an input unit such as a switch or a keyboard, and allows for input and setting of information such as temperature, voltage, and time as needed.

[0100] Next, refer to Figure 6 The following describes an example of the application of the temperature measuring device 10. An example of an endoscope suitable for observing the inside of the human body is shown. A doctor Tm inserts the front end of an endoscope Es through the mouth of a patient Pt to observe and examine internal organs. The catheter Ct is inserted through the conduit P of the endoscope Es, and a temperature-sensing portion 41 serving as a probe extends from the conduit P. An objective lens O and an illumination lens L are provided at the front end of the endoscope Es, and an imaging element (not shown) is provided near the front end. Images captured by the imaging element are displayed so that the doctor Tm can observe.

[0101] Therefore, during endoscopic examination, as described in detail later, the temperature of the affected part can be measured by bringing the temperature sensing portion 41 of the temperature measuring device 10 into contact with the affected part of the patient, thereby performing thermal response exploration of the affected part, for example, contributing to the diagnosis of tumors.

[0102] The temperature measuring device of this embodiment is not limited to being incorporated into a catheter, but can be independently configured as a temperature measuring device to measure skin temperature, body temperature, or the surface temperature of an object in an industrial field.

[0103] Next, regarding the case of measuring the temperature of the object to be measured and the case of measuring the temperature attenuation, refer to Figures 7 to 9 The operation of the temperature measuring device 10 will be described. Figure 7 This is a flowchart showing an overview of temperature measurement. Figure 8 This is a time chart showing a map of heat pulse generation during temperature decay measurement. The horizontal axis represents the measurement time (seconds) and the vertical axis represents the measurement temperature (°C) of the thin film temperature sensing element used for measurement. Figure 9 This is a flowchart showing the outline of temperature decay measurement. These actions are mainly performed by Figure 5 The program of the control processing unit 5 shown is executed.

[0104] Temperature measurement

[0105] like Figure 7 As shown, the temperature measuring device 10 is powered on and activated. The temperature sensing unit 41, acting as a probe, is inserted into the human body along with the endoscope Es (step S1). Next, the ambient temperature is set to a predetermined temperature lower than that of the subject being measured using the temperature control element 3, the heat sink 31, and the thin-film temperature sensing element 32 (step S2). For example, if the temperature of the affected area of ​​the subject being measured is 37°C, the ambient temperature is set to 0.5°C to 10°C lower, preferably 2°C to 3°C lower.

[0106] In principle, when using the temperature measuring device 10, the ambient temperature, or at least the measurement thin-film temperature sensing element 1, must be lower than the temperature of the object being measured. In environments such as the abdominal cavity or internal organs during endoscopic surgery, the affected part of the object being measured is at the same temperature as the surrounding environment, making it difficult to measure the temperature of the affected part with high precision and accuracy.

[0107] In this embodiment, a Peltier element serving as the temperature control element 3 cools the heat sink 31, setting the temperature of the thin-film temperature-sensing element 1 for measurement slightly lower than that of the object being measured. While being monitored by the thin-film temperature-sensing element 32 for temperature control, the heat sink 31 is temperature-controlled by the temperature control element 3, maintaining a temperature (several degrees Celsius) lower than that of the object being measured. This allows the protective heating thin-film temperature-sensing element 2 to self-heat, enabling heat exchange between the measuring thin-film temperature-sensing element 1 and the protective heating thin-film temperature-sensing element 2, thus equalizing the temperatures of the two elements. Heat generated by the temperature control element 3 is dissipated through the heat dissipation fins 33.

[0108] In addition, when the temperature of the object to be measured is always higher than the ambient temperature, the heat sink 31 can be omitted. However, by providing the heat sink 31, stable and more accurate temperature measurement can be expected.

[0109] Next, the temperature sensing unit 41 (the thin film temperature sensing element 1 for measurement) is brought into contact with the affected area of ​​the measured object (step S3). In this state, the temperature of the thin film temperature sensing element 1 for measurement is monitored (step S4), and control is performed to ensure that the temperature of the thin film temperature sensing element 1 for measurement is equal to the temperature of the protective heating thin film temperature sensing element 2 (step S5).

[0110] Specifically, when the thin-film temperature-sensing element 1 for measurement is brought into contact with the measured object, the control processing unit 5 controls the thin-film temperature-sensing element 2 so that its resistance becomes equal to that of the thin-film temperature-sensing element 1 for measurement. Furthermore, the thin-film temperature-sensing element 2 for protection and heating generates heat to a temperature equal to that of the thin-film temperature-sensing element 1 for measurement. This equalizes the temperatures of the surface of the affected part of the measured object, the thin-film temperature-sensing element 1 for measurement, and the thin-film temperature-sensing element 2 for protection and heating. This prevents heat transfer from the thin-film temperature-sensing element 1 for measurement to the thin-film temperature-sensing element 2 for protection and heating, and also prevents heat transfer from the surface of the affected part to the thin-film temperature-sensing element 1 for measurement.

[0111] In this way, the temperature measuring device 10 is provided with the protective heating thin film temperature sensing element 2 relative to the measuring thin film temperature sensing element 1 through the insulation layer S1 of appropriate layer thickness. This can offset the heat flowing from the surface of the measured object along the measuring thin film temperature sensing element 1 and the conductive wires, thereby minimizing the heat loss and enabling the temperature to be measured without changing the state of the measured object.

[0112] Next, it is detected that the temperature of the thin film temperature sensing element 1 for measurement and the temperature of the affected part have reached a thermal equilibrium state (step 6), and the temperature measurement result of the affected part as the measured object is displayed or recorded and output (step 7).

[0113] The main steps of the above temperature measurement method include the following steps: setting the ambient temperature to a temperature lower than the object to be measured by a certain temperature; bringing the temperature sensing portion 41 into contact with the object to be measured; controlling so that the temperature of the measurement thin film temperature sensing element 1 and the temperature of the protective heating thin film temperature sensing element 2 become equal; and outputting the temperature measurement result of the object to be measured.

[0114] The temperature measuring method of the temperature measuring device 10 can measure the temperature of the object to be measured with high precision and accuracy. Moreover, the thin film temperature sensing element has a small heat capacity and is highly sensitive, and can perform measurements in a short time with a high-speed response of the order of milliseconds.

[0115] In addition, regarding step 2 of controlling the ambient temperature setting to a temperature that is a fixed temperature lower than that of the object to be measured, in the industrial field, in an environment where the ambient temperature is 15°C and the surface temperature of the component serving as the object to be measured is in a cooled state and is 10°C, by controlling the ambient temperature setting to a temperature that is a fixed temperature lower than that of the object to be measured, for example, 8°C, high-precision temperature measurement of the object to be measured can be expected.

[0116] Temperature decay measurement

[0117] As an example, refer to Figure 8 as well as Figure 9 The following describes a temperature decay measurement method for diagnosing skin cancer or internal organ cancer in the biological tissue of a measured object. Temperature decay measurement estimates the thermal conductivity of the measured object using the so-called thermal pulse decay method.

[0118] In this embodiment, multiple heat pulses of varying duration, including short and long heat pulses at a constant power, are supplied to the thin-film temperature-sensing element 1 for measurement, causing it to heat at a predetermined temperature. Subsequently, the temperature change on the surface of the object being measured is measured using the thin-film temperature-sensing element 1, and the thermal conductivity is calculated based on the temperature decay after heating. Furthermore, the protective heating thin-film temperature-sensing element 2 is also heated in the same manner as the thin-film temperature-sensing element 1 for measurement.

[0119] Cancerous tissue has greater biological activity than healthy tissue due to metabolism or blood flow, and the energy deprived when heat is applied increases, so the apparent thermal conductivity measured becomes higher. It has been confirmed that the larger the volume of the cancerous tissue, the higher the apparent thermal conductivity. Therefore, by measuring the apparent thermal conductivity inferred based on the temperature decay of the affected part, tumor diagnosis can be performed. Specifically, a short-term heat pulse is applied to the affected part, and the cancer activity state of the epidermis is measured based on the apparent thermal conductivity inferred based on its temperature decay. Similarly, a long-term heat pulse is applied to the affected part, and the cancer activity state in the dermis is measured based on the thermal conductivity inferred based on its temperature decay. In the measurement of the cancer activity state in the dermis, although the heat penetration depth increases, due to the large influence of the epidermis, the apparent thermal conductivity containing information of deeper tissues is still measured.

[0120] In this way, the use of short-duration heat pulses can be expected to significantly contribute to the diagnosis of early-stage skin cancer. Furthermore, by administering short-duration heat pulses simultaneously with long-duration heat pulses, it is possible to identify thermal properties deep within a living organism, enabling the investigation of thermal properties near the surface of the organism, from the skin surface down to the dermis.

[0121] like Figure 8 as well as Figure 9As shown, a short-duration heat pulse (short pulse) with a fixed power of several milliseconds is applied to the thin film temperature sensing element 1 for measurement as a first heat pulse (step S1). During a fixed time of several seconds after the application stops, the thin film temperature sensing element 1 for measurement is monitored and the temperature decay characteristics are detected to calculate the thermal conductivity (step S2). Next, a long-duration heat pulse (long pulse) with a fixed power of a duration longer than the first heat pulse is applied as a second heat pulse (step S3). During a fixed time of several seconds after the application stops, the thin film temperature sensing element 1 for measurement is monitored and the temperature decay characteristics are detected to calculate the thermal conductivity (step S4). The calculation results of the thermal conductivity of steps S2 and S4 or the diagnostic results based on the thermal conductivity are output (step S5).

[0122] Therefore, the main process of the temperature decay measurement method includes the following steps: bringing the temperature sensing part into contact with the object to be measured; applying a first heat pulse of fixed power to the thin film temperature sensing element for measurement; detecting the temperature decay characteristics of the thin film temperature sensing element for measurement at a fixed time after the application of the first heat pulse stops; applying a second heat pulse of fixed power with a time width longer than the first heat pulse to the thin film temperature sensing element for measurement; and detecting the temperature decay characteristics of the thin film temperature sensing element for measurement at a fixed time after the application of the second heat pulse stops.

[0123] According to the temperature decay measurement method described above, the temperature decay characteristics from the epidermis to the dermis of a living being are detected to calculate the thermal conductivity, thereby enabling non-invasive diagnosis of the affected part.

[0124] [Second embodiment]

[0125] Next, refer to Figure 10 A temperature measuring device according to a second embodiment of the present invention will be described. Figure 10 The map showing the temperature measuring device is a schematic diagram for explaining the measurement state. Components identical or corresponding to those in the first embodiment are denoted by the same reference numerals and duplicate descriptions are omitted.

[0126] The basic structure of this embodiment is the same as that of the first embodiment, consisting of a temperature measuring device 10 incorporated into a pen-shaped holder 6. The outer shell 4 is a slide bar, which is slidably received in the holder 6. The tip of the slide bar is a temperature sensing portion 41, which serves as a probe for detecting temperature.

[0127] Furthermore, a coil spring 61 is provided at the rear end of the slide rod as an elastic member. This spring 61 elastically applies force, causing the temperature sensing portion 41 to protrude toward the front end, that is, toward the measured object (e.g., the skin surface). This ensures a constant pressure against the measured object by the temperature sensing portion 41 during measurement, potentially improving measurement accuracy. Furthermore, a lead wire 62 extends from the rear end of the bracket 6 and is connected to the control processing unit.

[0128] According to this embodiment, similar to the first embodiment, a temperature measurement device, a temperature measurement method, and a temperature decay measurement method can be provided. These devices can measure the temperature of a measured object, such as the surface of skin or an object, with high precision, high accuracy, and high-speed responsiveness. Furthermore, the temperature of the thin-film temperature sensing element used for measurement can be maintained lower than the temperature of the measured object. Furthermore, the pressing pressure of the temperature sensing portion 41 toward the measured object can be maintained constant.

[0129] Furthermore, the temperature measuring device, temperature measuring method, and temperature decay measuring method of the present invention described above are preferably applied to biological measurements such as thermometers, but are not limited thereto and can also be applied to measuring the surface temperature of objects in the industrial field.

[0130] The present invention is not limited to the structures of the above-described embodiments, and various modifications can be made without departing from the scope of the invention. Moreover, the above-described embodiment is provided as an example and is not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms and can be omitted, replaced, or modified in various ways. These embodiments or their modifications are included in the scope or spirit of the invention and are included in the scope of the invention described in the claims and their equivalents.

Claims

1. A temperature measuring device, characterized in that: include: Temperature sensing part, detecting temperature; a thin film temperature sensing element for measurement, capable of measuring temperature by bringing the temperature sensing portion into contact with a body to be measured; a protective heating thin film temperature sensing element, arranged to be heat-exchangeable with the measuring thin film temperature sensing element via a heat insulating layer, and controlled so as to have a temperature equal to that of the measuring thin film temperature sensing element; a temperature control element capable of setting the thin film temperature sensing element for measurement to a temperature state that is a fixed temperature lower than the temperature of the object to be measured; as well as The control processing unit controls the thin film temperature sensing element for measurement, the thin film temperature sensing element for protection heating, and the temperature control element.

2. The temperature measuring device according to claim 1, wherein The thin film temperature sensing element for measurement and the thin film temperature sensing element for protection and heating are thin film thermistors.

3. The temperature measuring device according to claim 2, characterized in that The thin film temperature sensing element for measurement and the thin film temperature sensing element for protection and heating include a substrate, a conductive layer and a thin film element layer formed on the substrate, and the thickness of the substrate is formed to be 200 μm or less.

4. The temperature measuring device according to any one of claims 1 to 3, characterized in that The thin film temperature sensing element for measurement and the thin film temperature sensing element for protection and heating are thin film temperature sensing elements with the same specifications and characteristics.

5. The temperature measuring device according to any one of claims 1 to 3, characterized in that The temperature control element is a Peltier element.

6. The temperature measuring device according to any one of claims 1 to 3, characterized in that The heat insulating layer is an air layer, and the layer thickness is formed to be 0.05 mm to 1 mm.

7. The temperature measuring device according to any one of claims 1 to 3, characterized in that The thin film temperature sensing element for measurement, the thin film temperature sensing element for protection and heating, and the temperature control element are incorporated into the distal end portion of the catheter.

8. The temperature measuring device according to any one of claims 1 to 3, characterized in that The thin film temperature sensing element for measurement, the thin film temperature sensing element for protection and heating, and the temperature control element are incorporated into a pen-shaped holder.

9. The temperature measuring device according to any one of claims 1 to 3, characterized in that The control processing unit controls to apply a first heat pulse of constant power to the thin film temperature sensing element for measurement, and to apply a second heat pulse of constant power having a duration longer than the first heat pulse to the thin film temperature sensing element for measurement.

10. A temperature measurement method, characterized in that: include: Temperature sensing part, detecting temperature; The thin film temperature sensing element can measure the temperature; a protective heating thin film temperature sensing element, arranged with the measuring thin film temperature sensing element separated by a heat insulating layer; and a temperature control element capable of controlling the temperature of the measuring thin film temperature sensing element, The temperature measuring method comprises the following steps: The temperature control element is used to control the temperature of the thin film temperature sensing element for measurement to be a fixed temperature lower than that of the object to be measured; bringing the temperature sensing portion into contact with the object to be measured; Controlling so that the temperature of the thin film temperature sensing element for measurement becomes equal to the temperature of the thin film temperature sensing element for protection and heating; as well as The measurement result of the temperature of the object to be measured is output.

11. A method for measuring temperature decay, characterized in that: include: Temperature sensing part, detecting temperature; The thin film temperature sensing element can measure the temperature; a protective heating thin film temperature sensing element, arranged with the measuring thin film temperature sensing element separated by a heat insulating layer; and a temperature control element capable of controlling the temperature of the measuring thin film temperature sensing element, The temperature decay measurement method comprises the following steps: Controlling the temperature of the thin film temperature sensing element for measurement to be set to a temperature lower than a predetermined temperature of the object to be measured; bringing the temperature sensing portion into contact with the object to be measured; applying a first heat pulse of a constant power to the thin film temperature sensing element for measurement; detecting the temperature decay characteristics of the thin film temperature sensing element for measurement at a fixed time after the application of the first heat pulse stops; applying a second heat pulse of a constant power having a duration longer than that of the first heat pulse to the thin film temperature sensing element for measurement; as well as The temperature decay characteristics of the thin film temperature sensing element for measurement are detected at a predetermined time after the application of the second heat pulse is stopped.

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