Temperature measuring instrument and body temperature measuring method

Abstract

The invention is suitable for the technical field of body temperature measurement, and provides a temperature measuring instrument and a body temperature measuring method.The temperature measuring instrument comprises a shell, an infrared array sensor, an environment temperature sensor, a controller and a displayer, and the infrared array sensor, the environment temperature sensor and the controller are all arranged in the shell. The infrared array sensor is connected with the controller and used for collecting infrared radiation signals of a superficial artery measurement area of a testee, converting the infrared radiation signals into an initial temperature matrix and sending the initial temperature matrix to the controller. The environment temperature sensor is connected with the controller and used for collecting the environment temperature value of the environment where the testee is located and sending the environment temperature value to the controller. The controller is connected with the displayer and used for receiving the initial temperature matrix and the environment temperature value, determining the body temperature value of the testee according to the initial temperature matrix and the environment temperature value and displaying the body temperature value through the displayer. According to the temperature measurer, the measured temperature can better reflect the actual temperature of a testee.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of body temperature measurement, and particularly relates to a temperature measuring instrument and a body temperature measurement method. BACKGROUND

[0002] As a core physiological indicator of human health status, body temperature plays an irreplaceable role in disease prevention, diagnosis and health management. Accurate measurement of body temperature can timely discover fever symptoms and provide key basis for early screening of infectious diseases (such as influenza, etc.), which can effectively reduce the risk of disease transmission. In the medical scene, body temperature monitoring is an important reference for evaluating patient condition changes and judging treatment effect; in family nursing, accurate and convenient body temperature measurement tools are essential equipment for protecting the health of special groups such as children and the elderly.

[0003] At present, the existing non-contact infrared temperature measuring instrument can only measure the temperature of one point at a time, and cannot obtain the overall temperature distribution of the forehead. The measured temperature may be lower than the actual body temperature due to misalignment of the high temperature part, resulting in missed reports. In addition, single-point measurement is also susceptible to environmental temperature and other factors, leading to inaccurate body temperature measurement. SUMMARY

[0004] The application embodiment provides a temperature measuring instrument and a body temperature measurement method, which can solve the problem of low body temperature measurement accuracy caused by single measurement point, inaccurate positioning and imperfect environmental temperature compensation of the existing non-contact infrared temperature measuring instrument.

[0005] In a first aspect, the application embodiment provides a temperature measuring instrument, comprising: a shell, an infrared array sensor, an environmental temperature sensor, a controller and a display, wherein the infrared array sensor, the environmental temperature sensor and the controller are arranged inside the shell.

[0006] The infrared array sensor is connected with the controller, and is configured to collect an infrared radiation signal of a superficial artery measurement area of a subject, convert the infrared radiation signal into an initial temperature matrix, and send the initial temperature matrix to the controller.

[0007] The environmental temperature sensor is connected with the controller, and is configured to collect an environmental temperature value of an environment where the subject is located, and send the environmental temperature value to the controller.

[0008] The controller is connected with the display, and is configured to receive the initial temperature matrix and the environmental temperature value, and determine a body temperature value of the subject according to the initial temperature matrix and the environmental temperature value.

[0009] The display is arranged on the surface of the shell, and is configured to display the body temperature value.

[0010] In a possible implementation manner of the first aspect, the shell is provided with a detection portion facing the superficial artery measurement region of the subject, and an infrared optical assembly is arranged at an opening end face of the detection portion;

[0011] The infrared optical assembly is configured to focus the infrared radiation signal of the superficial artery measurement region of the subject to a detection surface of the infrared array sensor, so that the infrared array sensor collects the infrared radiation signal.

[0012] In a possible implementation manner of the first aspect, the infrared optical assembly is a superlens.

[0013] In the second aspect, the embodiments of the present application provide a body temperature measurement method, applied to the temperature measuring instrument described in any one of the above aspects, and the method comprises the following steps:

[0014] Obtaining an initial temperature matrix corresponding to an infrared radiation signal of a superficial artery measurement region of a subject and an environmental temperature value of an environment in which the subject is located;

[0015] Determining a body temperature value of the subject according to the initial temperature matrix and the environmental temperature value.

[0016] In a possible implementation manner of the second aspect, the step of obtaining the initial temperature matrix corresponding to the infrared radiation signal of the superficial artery measurement region of the subject and the environmental temperature value of the environment in which the subject is located comprises:

[0017] Collecting, by an infrared array sensor, the infrared radiation signal of the superficial artery measurement region of the subject focused by the infrared optical assembly, and converting, by the infrared array sensor, the infrared radiation signal into the initial temperature matrix;

[0018] Collecting, by an environmental temperature sensor, the environmental temperature value of the environment in which the subject is located.

[0019] In a possible implementation manner of the second aspect, the step of determining the body temperature value of the subject according to the initial temperature matrix and the environmental temperature value comprises:

[0020] According to a temperature compensation model and the environmental temperature value, performing correction processing on the initial temperature matrix to obtain a corrected temperature matrix;

[0021] According to temperature gradient feature values and regional temperature stability feature values extracted from the corrected temperature matrix, determining a target superficial artery vessel region of the superficial artery measurement region of the subject;

[0022] Peak value tracking processing is performed on the corrected temperature matrix corresponding to the target superficial artery blood vessel region, and a peak temperature value of the target superficial artery blood vessel region is determined, and the peak temperature value of the target superficial artery blood vessel region is taken as the body temperature value of the subject.

[0023] In a possible implementation of the second aspect, the correcting processing of the initial temperature matrix according to the temperature compensation model and the ambient temperature value to obtain the corrected temperature matrix comprises:

[0024] The initial temperature matrix is subjected to filter denoising processing based on a Gaussian filter denoising algorithm to obtain a filter denoised temperature matrix;

[0025] According to the temperature compensation model and the ambient temperature value, an ambient temperature compensation amount is calculated;

[0026] The filter denoised temperature matrix and the ambient temperature compensation amount are added to obtain the corrected temperature matrix; wherein the temperature compensation model is:

[0027] ΔT=k1(T1-T3)+k2(T2-T0)+k3(T1-T3)(T2-T0);

[0028] wherein ΔT is the ambient temperature compensation amount, T1 is a preset constant temperature unit temperature value, T2 is the ambient temperature value, T3 is an initial measurement temperature value corresponding to the initial temperature matrix, T0 is a standard ambient temperature value, k1 is a first compensation coefficient, k2 is a second compensation coefficient, and k3 is a third compensation coefficient.

[0029] In a possible implementation of the second aspect, the target superficial artery blood vessel region of the superficial artery measurement region of the subject is determined according to a temperature gradient feature value and a region temperature stability feature value extracted from the corrected temperature matrix, comprising:

[0030] Based on an edge detection algorithm, a horizontal direction temperature gradient value and a vertical direction temperature gradient value in the corrected temperature matrix are calculated respectively, and a comprehensive temperature gradient value is obtained according to the horizontal direction temperature gradient value and the vertical direction temperature gradient value;

[0031] According to a preset temperature gradient threshold, the temperature gradient feature value is extracted from the comprehensive temperature gradient value;

[0032] Based on a sliding window algorithm, a local temperature variance value corresponding to the corrected temperature matrix in a preset sliding window is calculated;

[0033] According to a preset variance threshold, the region temperature stability feature value is extracted from the local temperature variance value;

[0034] determine a potential blood vessel boundary position of a superficial artery measurement region of the subject according to the temperature gradient feature value and the regional temperature stability feature value;

[0035] determine a target superficial artery blood vessel region from the potential blood vessel boundary position of the superficial artery measurement region of the subject based on an adaptive threshold segmentation algorithm and a preset temperature difference value, wherein the preset temperature difference value is a temperature difference between the superficial artery blood vessel and the skin surrounding the blood vessel.

[0036] In a possible implementation of the second aspect, the determining of the target superficial artery blood vessel region from the potential blood vessel boundary position of the superficial artery measurement region of the subject based on the adaptive threshold segmentation algorithm and the preset temperature difference value comprises:

[0037] calculate an arithmetic mean value and a standard deviation value of the corrected temperature matrix;

[0038] calculate a dynamic temperature threshold value according to the arithmetic mean value and the standard deviation value of the corrected temperature matrix and the preset temperature difference value;

[0039] determine the target superficial artery blood vessel region as a region in which a temperature value in the corrected temperature matrix is greater than the dynamic temperature threshold value.

[0040] In a possible implementation of the second aspect, the performing of the peak value tracking processing on the corrected temperature matrix corresponding to the target superficial artery blood vessel region to determine a peak temperature value of the target superficial artery blood vessel region and taking the peak temperature value of the target superficial artery blood vessel region as the body temperature value of the subject comprises:

[0041] unfold the corrected temperature matrix corresponding to the target superficial artery blood vessel region along a column direction by row to obtain a plurality of one-dimensional temperature curves;

[0042] perform three-point sliding window processing on each of the one-dimensional temperature curves to determine a peak temperature point of each of the one-dimensional temperature curves and a peak temperature value corresponding to the peak temperature point of each of the one-dimensional temperature curves;

[0043] determine the peak temperature value of the target superficial artery blood vessel region according to the peak temperature value corresponding to the peak temperature point of each of the one-dimensional temperature curves, and take the peak temperature value of the target superficial artery blood vessel region as the body temperature value of the subject.

[0044] In a third aspect, an embodiment of the present application provides a body temperature measurement device, applied to the temperature measuring instrument in any of the above aspects, and the device comprises:

[0045] an acquisition module, configured to acquire an initial temperature matrix corresponding to an infrared radiation signal of a superficial artery measurement region of a subject and an ambient temperature value of an environment in which the subject is located.

[0046] determining a body temperature value of the subject according to the initial temperature matrix and the ambient temperature value.

[0047] In a fourth aspect, an embodiment of the present application provides a terminal device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the body temperature measurement method in any of the above aspects when executing the computer program.

[0048] In a fifth aspect, an embodiment of the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executable by a processor to implement the body temperature measurement method in any of the above aspects.

[0049] In a sixth aspect, an embodiment of the present application provides a computer program product, which, when running on a terminal device, causes the terminal device to execute the body temperature measurement method in any of the first aspect.

[0050] Compared with the prior art, the embodiment of the present application has the beneficial effects that:

[0051] The embodiment of the present application provides a temperature measuring instrument, including a shell, an infrared array sensor, an ambient temperature sensor, a controller and a display, wherein the infrared array sensor, the ambient temperature sensor and the controller are arranged inside the shell. The infrared array sensor is connected with the controller, is used for collecting infrared radiation signals of a superficial artery measurement area of a subject, converting the infrared radiation signals into an initial temperature matrix, and sending the initial temperature matrix to the controller; the ambient temperature sensor is connected with the controller, is used for collecting an ambient temperature value of an environment where the subject is located, and sending the ambient temperature value to the controller; the controller is connected with the display, is used for receiving the initial temperature matrix and the ambient temperature value, determining a body temperature value of the subject according to the initial temperature matrix and the ambient temperature value, and displaying the body temperature value through the display. The temperature measuring instrument scans and measures the superficial artery measurement area of the subject through the infrared array sensor, collects spatial temperature distribution to form the initial temperature matrix, which can reduce the inaccurate positioning of single-point measurement; and collects the ambient temperature value through the ambient temperature sensor, compensates the initial temperature matrix according to the received ambient temperature value through the controller, reduces the influence of the ambient temperature on the body temperature, and makes the measured temperature more reflect the actual temperature of the subject. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.

[0053] Figure 1 is a structural schematic diagram of a thermometer provided by an embodiment of the present application;

[0054] Figure 2 is a structural schematic diagram of a thermometer provided by another embodiment of the present application;

[0055] Figure 3 is a flowchart of a body temperature measurement method provided by an embodiment of the present application;

[0056] Figure 4 is a flowchart of a method for determining a body temperature value provided by an embodiment of the present application;

[0057] Figure 5 is an effect schematic diagram of a target superficial arterial blood vessel region before morphological processing provided by an embodiment of the present application;

[0058] Figure 6 is an effect schematic diagram of a target superficial arterial blood vessel region after morphological processing provided by an embodiment of the present application;

[0059] Figure 7 is a structural schematic diagram of a body temperature measurement device provided by an embodiment of the present application;

[0060] Figure 8 is a structural schematic diagram of a terminal device provided by an embodiment of the present application.

[0061] In the drawings, various reference signs represent:

[0062] 1-thermometer; 10-housing; 20-infrared array sensor; 30-environmental temperature sensor; 40-controller; 50-display; 60-switch measurement button; 11-probing part; 12-holding part;

[0063] 3-body temperature measurement device; 31-acquisition module; 32-determination module;

[0064] 4-terminal device; 41-memory; 42-processor. DETAILED DESCRIPTION

[0065] In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular architectures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods, devices, circuits, and

[0066] It is to be understood that the terminology "includes", "has", "holds", "contains" or "comprising", "including", "having" and the like, when used in the present specification and in the accompanying claims, are used in the sense of "including but not limited to", "including but not limited to", "including but not limited to" and "including but not limited to" respectively, and should be accorded a broad scope so as to encompass the various embodiments of the present application.

[0067] It is also to be understood that the terminology "and / or" as used in the present specification and in the accompanying claims, refers to one or more of the associated listed items, in any combination and all possible combinations, and includes these combinations.

[0068] As used in the present specification and in the accompanying claims, the term "if" can be interpreted as meaning "when" or "once" or "in response to a determination" or "in response to detecting" depending on the context. Similarly, the phrase "if it is determined" or "if [a described condition or event] is detected" can be interpreted to mean "once it is determined" or "in response to the determination" or "once [the described condition or event] is detected" or "in response to the detection [of the described condition or event]" depending on the context.

[0069] In addition, the terms "first", "second", "third", etc. as used in the description of the specification and the appended claims are used only to distinguish different instances of similar elements and do not imply or suggest relative importance.

[0070] The use of the terms "one embodiment", "some embodiments", "other embodiments", "another embodiment", "additional embodiments", etc. has been mentioned above. It is to be understood that these terms refer to some but not necessarily all embodiments of the present application. As such, these terms do not necessarily refer to the same embodiment or embodiments, unless otherwise specifically indicated. The terms "including", "containing", "having" and the like are used in their broadest sense and are intended to mean "including, but not limited to". The terms "coupled" and "connected" are used in their broadest sense and are intended to mean either an indirect or direct electrical or mechanical connection.

[0071] Traditional non-contact infrared thermometers (such as forehead thermometers) usually use single-point measurement of human body surface temperature, which is significantly affected by environmental temperature, local skin state (such as sweating, wind blowing), and other factors, and has a large deviation from the human core body temperature, usually more than ±1℃.

[0072] Superficial arteries (such as the frontal temporal superficial artery, the anterior cervical superficial artery, etc.) are the distal extension of the aorta and its branches, and the blood directly comes from the arterial blood pumped by the heart, which is quickly transported to the superficial artery area through large blood vessels without passing through peripheral tissues for sufficient heat dissipation. A large number of experimental data show that the deviation of the temperature of the superficial artery blood from the human core body temperature (such as the temperature of the blood in the pulmonary artery and the aorta) is ≤0.3℃, which is significantly better than the body surface temperature (the deviation of the body surface temperature from the human core temperature can reach 2℃-3℃). Moreover, the superficial artery is located 2mm-5mm below the skin and is surrounded by adipose tissue, fascia and other connective tissue to form a natural "heat insulation layer", which can effectively buffer the fluctuations of the environmental temperature. Comparative tests show that under the condition of an environmental temperature change of ±5℃, the temperature fluctuation of the superficial artery is only ±0.2℃, while the temperature fluctuation of the skin surface is more than ±1.5℃, indicating that the temperature of the superficial artery has stronger anti-interference ability.

[0073] The blood flow velocity of the superficial artery reaches 30cm / s-50cm / s, and the blood flow time is less than 0.5 seconds, which is hardly affected by the local tissue metabolic heat or heat dissipation process; the flow rate of venous blood is only 1 / 5-1 / 3 of that of arterial blood, and the temperature after heat exchange with peripheral tissues is 1℃-2℃ lower than the human core body temperature; the capillary blood is easily affected by local inflammation, exercise hyperemia, etc. due to its small diameter and slow blood flow, and the temperature fluctuation can reach ±1℃ or more. Therefore, the superficial artery is an ideal carrier for transmitting core body temperature signals. At the same time, the superficial artery meets the anatomical feature of "subcutaneous depth ≤5mm", and the epidermis and dermis above it have weak absorption and scattering effects on infrared radiation (8μm-14μm band). A large number of experimental and literature data verify that when infrared radiation penetrates through the superficial skin structure, the energy attenuation rate is <15%, which can be effectively captured by the infrared array sensor, meeting the signal strength requirement of non-contact measurement.

[0074] Therefore, the present application provides a thermometer which scans the surface of the human skin through an infrared array sensor, locates and measures the temperature of the subcutaneous superficial artery, and realizes non-contact precise temperature measurement by using the high correlation between the superficial artery and the core body temperature, solving the precision defect of the traditional technology.

[0075] The thermometer measures the body temperature of the superficial artery measurement area of the subject, and the superficial artery measurement area of the subject has multiple parts to choose from. The priority of the selection is as follows:

[0076] (1) First choice: forehead. The forehead is the area with the highest frequency of daily exposure. The superficial temporal artery, the supratrochlear artery, and the supraorbital artery on the forehead run stably (symmetrically distributed along the surface of the frontal bone, with an anatomical variation rate of <5%). The infrared array sensor can clearly capture the temperature gradient within a distance of 1-3 cm (0.8-1.2°C higher than the surrounding tissue in the superficial artery area), and the scanning path (such as from the center of the eyebrow to the temple) is highly matched with the blood vessel direction, with a positioning accuracy of more than 95%, which is the optimal measurement site.

[0077] (2) Second choice: neck, back of hand, and wrist. The temperature difference between the superficial artery and the surrounding skin in these parts is 0.5-0.9°C. The superficial artery in the neck is located in the superficial layer of the sternocleidomastoid muscle, but it is easily blocked by scarves and high-necked clothing, and the actual measurable probability is only 60-70% of the forehead. The superficial artery in the wrist has a small diameter (e.g., <2 mm), and it moves with hand movements (e.g., clenching the fist), which is 15-20% less stable than the forehead. The above-mentioned parts need the infrared array sensor to switch to a wide field of view (e.g., 60°) to cover the blood vessel distribution range, which may introduce background interference. It is suitable for alternative solutions when the forehead is blocked, but the measurement accuracy is relatively lower than the forehead.

[0078] (3) Special scene site: elbow, etc. The superficial artery in the elbow (such as the branch of the brachial artery) has a large diameter (e.g., 3-4 mm), and the temperature difference between the superficial artery and the surrounding skin in this part is 1.0-1.5°C, with high infrared signal intensity. It is suitable for precise measurement in medical scenarios (such as when the patient is lying down). However, this part has a low frequency of daily exposure and is not convenient to operate, so it is only used as a supplementary measurement option.

[0079] Please refer to Figure 1 , Figure 1 is a structural schematic diagram of a temperature measuring instrument according to an embodiment of the present application. Figure 1 In the temperature measuring instrument 1, the temperature measuring instrument 1 comprises a shell 10, an infrared array sensor 20, an ambient temperature sensor 30, a controller 40, and a display 50, wherein the infrared array sensor 20, the ambient temperature sensor 30, and the controller 40 are all arranged inside the shell 10.

[0080] The infrared array sensor 20 is connected with the controller 40, and is used to collect the infrared radiation signal of the superficial artery measurement area of the subject, convert the infrared radiation signal into an initial temperature matrix, and send the initial temperature matrix to the controller 40.

[0081] The ambient temperature sensor 30 is connected with the controller 40, and is used to collect the ambient temperature value of the environment where the subject is located, and send the ambient temperature value to the controller 40.

[0082] The controller 40 is connected with the display 50, and is configured to receive the initial temperature matrix and the ambient temperature value, and determine the body temperature value of the subject according to the initial temperature matrix and the ambient temperature value.

[0083] The display 50 is arranged on the surface of the shell, and is configured to display the body temperature value.

[0084] As shown in Figure 1 The shell 10 is an external protective structure of the thermometer 1, and is usually made of plastic, metal or other materials, and can accommodate and fix the infrared array sensor 20, the ambient temperature sensor 30, the controller 40 and the display 50.

[0085] The infrared array sensor 20 is a sensor array that can detect the infrared radiation signal of the surface of an object. The infrared array sensor 20 is composed of a plurality of infrared sensing elements (such as thermocouples and pyroelectric sensors). The infrared sensing elements can be arranged in a two-dimensional matrix. Each element can independently detect the infrared radiation signal of a point, and then the infrared array sensor 20 can simultaneously collect the temperature data of multiple points in the measurement region. For example, a 4x4 array infrared array sensor includes 16 independent infrared sensing elements, which can simultaneously collect the temperature data of 16 points. Through transverse scanning from the glabella to the temple of the forehead, the probe window coverage area can accurately locate the position of the superficial temporal artery, identify the highest temperature area, and has strong anti-interference ability and small temperature measurement result error.

[0086] The superficial artery measurement region is a region where the superficial arteries of the human body are distributed, such as the superficial temporal artery on the forehead and the radial artery on the wrist. The temperature change of the superficial artery can quickly reflect the core body temperature of the human body. When the measurement region is the superficial temporal artery, the projection width of the superficial temporal artery on the body surface is about 5mm-8mm. The detection range of a single infrared sensing element is usually 2mm-3mm. Therefore, for example, the overall coverage range of a 4x4 infrared array sensor is about 8mm-12mm, which matches the width of the superficial temporal artery. If the array of the infrared array sensor is too small (such as a 1x4 linear array), the anti-interference ability is weak, such as shielding one infrared sensing element, which may lose the blood vessel signal, and it is difficult to analyze the highest temperature area by comparing the temperature. Therefore, in order to ensure the measurement accuracy, the infrared array sensor can adopt a 4x4 array or a higher array when measuring the superficial artery. It should be noted that in the present embodiment, the specific value of the array of the infrared array sensor 20 is not limited, and the infrared array sensor 20 with a suitable array can be selected according to the position of the superficial artery measurement region.

[0087] In this embodiment, the infrared array sensor 20 measures the infrared radiation signal of the superficial artery measurement area (such as the temporal superficial artery) of the subject, obtains temperature distribution information, and converts the infrared radiation signal into a digital signal to form an initial temperature matrix containing multiple temperature points; finally, the initial temperature matrix is sent to the controller 40 for subsequent processing and analysis by the controller 40. The initial temperature matrix is a two-dimensional rectangle composed of multi-point temperature data collected by the infrared array sensor 20, and each element represents the temperature value of a point in the measurement area, which can reflect the temperature distribution of the measurement area. By analyzing the temperature distribution in the initial temperature matrix, the position of the superficial artery can be located, and the accuracy of the body temperature measurement can be improved.

[0088] The ambient temperature sensor 30 is a sensor that can measure the ambient temperature, usually using the principles of thermistor, thermocouple or digital temperature sensor. In this embodiment, the ambient temperature sensor 30 can monitor the temperature of the environment where the subject is in real time, and send the ambient temperature value to the controller 40 for temperature compensation of the initial temperature matrix, thereby improving the accuracy of the body temperature measurement.

[0089] The controller 40 is the core control unit of the thermometer 1, usually composed of a microprocessor or a digital processor, mainly for data processing, algorithm running and system control. In this embodiment, the controller 40 receives the initial temperature matrix sent by the infrared array sensor 20 and the ambient temperature value sent by the ambient temperature sensor 30, processes the initial temperature matrix and combines the ambient temperature value to calculate the body temperature value of the subject. Finally, the calculated body temperature value is sent to the display 50 for display.

[0090] The display 50 is an output device for displaying the measurement results. The display 50 is arranged on the surface of the shell 10, and the display 50 can display the body temperature of the subject in digital or graphical form, which is convenient for users to read. The body temperature value displayed by the display 50 can be in Celsius or Fahrenheit. Moreover, according to the design requirements, the display 50 can also display other information such as measurement state, error prompt, ambient temperature, etc.

[0091] It should be noted that in actual application, assuming that the measurement site is the temporal superficial artery on the forehead, the user holds the thermometer 1, aligns the detection window of the thermometer 1 with the forehead area of the subject, and the distance between the forehead surface is 3-5 cm, then performs horizontal scanning from the center of the eyebrow to the temple, and finally near the temple, the body temperature value of the subject can be displayed on the display 50.

[0092] It can be understood that the temperature measuring instrument 1 provided by the embodiment comprises a shell 10, an infrared array sensor 20, an ambient temperature sensor 30, a controller 40 and a display 50, wherein the infrared array sensor 20, the ambient temperature sensor 30 and the controller 40 are arranged inside the shell 10. The infrared array sensor 20 is connected with the controller 40, used for collecting infrared radiation signals of a superficial artery measurement area of a subject, converting the infrared radiation signals into an initial temperature matrix, and sending the initial temperature matrix to the controller 40; the ambient temperature sensor 30 is connected with the controller 40, used for collecting an ambient temperature value of an environment where the subject is located, and sending the ambient temperature value to the controller 40; the controller 40 is connected with the display 50, used for receiving the initial temperature matrix and the ambient temperature value, determining a body temperature value of the subject according to the initial temperature matrix and the ambient temperature value, and displaying the body temperature value through the display 50. The temperature measuring instrument 1 scans and measures the superficial artery measurement area of the subject through the infrared array sensor 20, collects spatial temperature distribution to form the initial temperature matrix, which can reduce the case of inaccurate positioning of single-point measurement; and collects the ambient temperature value through the ambient temperature sensor 30, compensates the initial temperature matrix according to the received ambient temperature value through the controller 40, reduces the influence of the ambient temperature on the body temperature, and makes the measured temperature more reflect the actual temperature of the subject.

[0093] In some examples, as shown in Figure 2 , Figure 2 is a structural schematic diagram of a temperature measuring instrument provided by another embodiment of the present application. As shown in Figure 2 , the shell 10 is provided with a detection part 11 facing the superficial artery measurement area of the subject, and an infrared optical assembly is arranged at the opening end face of the detection part 11, which is used for focusing the infrared radiation signals of the superficial artery measurement area of the subject to the detection surface of the infrared array sensor, so that the infrared array sensor collects the infrared radiation signals.

[0094] One end of the shell 10 is the detection part 11, and the other end is the holding part 12. The detection part 11 is a structure designed on the shell 10 and facing the superficial artery measurement area of the subject. The opening end face is away from the one end of the main body of the shell 10, and can face the superficial artery measurement area when measuring the body temperature. The detection part 11 also has an internal channel for optimizing the transmission path of the infrared radiation signals.

[0095] Since the infrared radiation signal of the superficial artery measurement area is divergent, the energy density decreases with the increase of the distance, and the detection surface size of the infrared array sensor 20 is limited, if the infrared radiation signal is directly received, it will lead to insufficient signal strength and low signal-to-noise ratio, therefore, an infrared optical assembly can be arranged at the opening end surface of the detection part 11. The infrared optical assembly can focus the infrared radiation signal to the detection surface of the infrared array sensor 20, forming an infrared radiation signal with higher energy density, so that the infrared array sensor 20 collects the infrared radiation signal.

[0096] In some examples, the infrared optical assembly is a combination assembly of a traditional optical lens and a filter.

[0097] The combination assembly of the traditional optical lens and the filter is a common component in the infrared optical system. The traditional optical lens focuses the infrared light beam to the detection surface of the infrared array sensor 20 through curved surface refraction. The filter only allows infrared light of a specific waveband to pass through, which can suppress background noise and improve signal-to-noise ratio. Combining the traditional optical lens and the filter can accurately measure the temperature of the human body surface and avoid environmental radiation interference.

[0098] In some examples, the infrared optical assembly is a metalens.

[0099] The metalens is a two-dimensional planar lens based on metasurface, which precisely controls the phase, amplitude and polarization state of light wave through subwavelength scale artificial nanostructure, realizing the functions of focusing and imaging of traditional lenses. The metalens can realize complex functions such as focusing and imaging through a single piece of structure, which can significantly reduce the volume and weight of the detection part 11 while improving the signal-to-noise ratio of the infrared radiation signal.

[0100] In some examples, the detection surface of the infrared array sensor 20 is parallel to the opening end surface of the detection part 11, and the central axis of the detection surface of the infrared array sensor 20 coincides with the central axis of the opening end surface of the detection part 11.

[0101] The detection surface of the infrared array sensor 20 is the end surface for directly receiving the infrared radiation signal, which is usually composed of a plurality of infrared sensing elements arranged in an array. The infrared array sensor 20 can be arranged at the internal channel of the detection part 11, the detection surface of the infrared array sensor 20 is parallel to the normal direction of the opening end surface of the detection part 11, that is, the detection surface of the infrared array sensor 20 is parallel to the opening end surface of the detection part 11, and the center point of the detection surface of the infrared array sensor 20 and the center point of the opening end surface of the detection part 11 are located on the same axis, which can ensure that the detection surface of the infrared array sensor 20 is perpendicular to the measurement area, avoiding angle deviation to cause errors in temperature calculation of the thermometer.

[0102] In some examples, the grip portion 12 of the housing 10 is provided with an inwardly recessed groove with a horizontal bottom side, and the display 50 is disposed in the inner wall area of ​​the groove.

[0103] like Figure 2 As shown, the grip portion 12 is the user's handheld area for the thermometer 1. An inwardly recessed groove is provided in the grip portion 12, the bottom side of which is horizontal, providing a stable mounting reference surface for the display 50. The display 50 is designed to correspond to this groove area and can be fixed by various methods such as snaps, adhesives, or magnets, achieving integration between the housing 10 and the display 50. The groove accommodates the display 50, preventing it from protruding and causing discomfort for the user. Furthermore, by placing the display 50 in the center of the groove, the user's gaze can naturally focus on the screen of the display 50 when holding it, shortening the user's reaction time.

[0104] In some examples, a switch measurement button 60 is provided on the grip portion 12 of the housing 10. The switch measurement button 60 is connected to the controller 40 and the power supply (not shown in the figure) respectively, and is used to turn the thermometer 1 on or off; and is also used to send a measurement start signal to the controller 40 so that the controller 40 controls the infrared array sensor 20 to collect infrared radiation signals when it receives the measurement start signal.

[0105] It should be noted that the thermometer 1 in this embodiment also includes a power supply (not shown in the figure). The power supply is the energy supply unit for the thermometer 1 and establishes an electrical connection with the infrared array sensor 20, ambient temperature sensor 30, controller 40, display 50, and switch measurement button 60. The power supply can use two AA batteries as the power source, which is compatible with the voltage requirements of the low-power electronic components of the thermometer 1. A battery compartment (made of ABS plastic, with a size suitable for two AA batteries installed in series) is provided inside the housing 10 of the thermometer 1. The battery compartment has built-in metal contact pieces (made of brass to ensure conductivity stability) and is equipped with an anti-reverse installation structure (the protruding buckle corresponds to the battery polarity to prevent the battery from being installed backwards and causing circuit damage). The battery compartment is integrated inside the grip portion 12 of the housing 10 (e.g., adjacent to the controller 40 to shorten wire length and reduce power consumption). A removable battery cover is provided on the surface of the grip portion 12 of the housing 10, which is fixed by a snap-on design and can be opened without tools to replace the battery. The battery cover is marked with a battery polarity diagram ("+", "-") to guide the user to install correctly. The power supply path for each component is as follows: the positive output terminal of the battery compartment is connected to the switch measurement button 60, and then to the power input terminal of the controller 40. At the same time, it is connected to the power pins of the infrared array sensor 20, the ambient temperature sensor 30, and the display 50 through wire branches; the negative output terminal of the battery compartment is directly grounded to the negative pin of each component, forming a complete power supply circuit.

[0106] likeFigure 2 As shown, a switch measurement button 60 is also provided on the grip portion 12 of the housing 10. This switch measurement button 60 is integrated into the grip portion 12 and connected to the controller 40 and the power supply. The switch measurement button 60 can be used to turn the thermometer 1 on or off, realizing the convenience and safety of thermometer operation. The switch measurement button 60 is located on the grip portion 12, which allows the user to directly trigger it when holding the thermometer with one hand without adjusting the hand posture.

[0107] The switch measurement button 60 also has the function of starting body temperature measurement. When the thermometer 1 is in standby mode, it can respond to the user's long press of the switch measurement button 60 and send a measurement start signal to the controller 40 so that the controller 40 can control the infrared array sensor 20 to collect infrared radiation signals when it receives the measurement start signal.

[0108] In practical applications, for example, when a user uses thermometer 1 to measure the body temperature of a subject's superficial temporal artery on the forehead, the user presses the switch measurement button 60 on thermometer 1 for the first time. Power is supplied to all components in thermometer 1, turning it on and putting it into standby mode. When the user presses the switch measurement button 60 again while the thermometer is in standby mode, the switch measurement button 60 sends a measurement start signal to controller 40. Upon receiving this signal, controller 40 controls infrared array sensor 20 to collect infrared radiation signals, initiating the body temperature measurement. The user then holds thermometer 1 and scans the forehead horizontally from the center of the eyebrows to the temples for 3 seconds. The thermometer 1 will then emit a "beep" sound to indicate that the measurement is complete and display the result on display 50. If thermometer 1 remains inactive for 30 seconds, it will automatically enter a low-power standby mode (at which point only display 50 is powered off). When the user presses the switch measurement button 60 for 3 seconds, the power supply to all components is cut off, and thermometer 1 turns off.

[0109] In some examples, the probe 11 of the housing 10 is cylindrical.

[0110] like Figure 2 As shown, the detection part 11 of the housing 10 is cylindrical. By setting the detection part 11 to a cylindrical shape, the axial symmetry of the infrared array sensor 20, the infrared optical components, and the opening end face of the detection part 11 can be ensured, which can reduce the measurement error caused by optical path offset. In this embodiment, the specific shape of the gripping part 12 of the housing 10 is not limited.

[0111] It can be understood that the temperature measuring instrument provided by the present application has the following advantages compared with the existing non-contact infrared measuring instrument: (1) The infrared array sensor can accurately locate the superficial artery by collecting the spatial temperature distribution, and the temperature measuring accuracy is significantly improved, which is closer to the core body temperature of the human body. (2) The integrated environmental temperature sensor and dynamic compensation algorithm can solve the error problem in high and low temperature environments, and at the same time allow slight hair and skin wrinkle coverage, avoid the shielding area through multi-point data, and have strong anti-physical interference ability. (3) Through non-contact measurement, there is no need to touch the skin, which avoids cross infection, is suitable for crowded scenes such as hospitals and kindergartens, and non-invasive measurement makes the measured person easy to accept. At the same time, the infrared array sensor detection window has a large coverage area, can accurately identify the position of the superficial artery, greatly improves the operation convenience, and is suitable for a wider population. (4) The total time of multi-point data acquisition and algorithm processing is less than 2s, and there is no need to wait for the body surface temperature and the environment to balance, so that the body temperature value can be quickly measured, the response speed is fast, and the user waiting time is reduced. (5) The temperature measuring instrument does not need dangerous materials such as glass and mercury, and the shell can be made of food-grade ABS plastic, which is anti-falling and durable, and is suitable for family scenes with children. The infrared array sensor and the processing chip can be miniaturized and integrated, and the lens system can also be replaced by a metasurface material (such as a super lens), which greatly reduces the device volume, and balances portability and functionality. At the same time, there is no exposed probe (the infrared sensing window is a sealed design), and there is no need for frequent disinfection, easy maintenance, and suitable for high-frequency use scenarios such as medical places.

[0112] Please refer to Figure 3 , Figure 3 is a flow diagram of a body temperature measurement method provided by an embodiment of the present application. As an example but not limitation, the method can be applied to the temperature measuring instrument 1, and the method comprises:

[0113] S101, acquiring an initial temperature matrix corresponding to an infrared radiation signal of a superficial artery measurement area of a measured person and an environmental temperature value of an environment where the measured person is located.

[0114] S102, determining a body temperature value of the measured person according to the initial temperature matrix and the environmental temperature value.

[0115] In step S101, the initial temperature matrix corresponding to the infrared radiation signal of the superficial artery measurement area of the measured person and the environmental temperature value of the environment where the measured person is located are acquired, comprising:

[0116] The infrared radiation signal of the superficial artery measurement area of the measured person focused by the infrared optical assembly is collected by the infrared array sensor, and the infrared radiation signal is converted into an initial temperature matrix by the infrared array sensor.

[0117] The environmental temperature value of the environment where the measured person is located is collected by the environmental temperature sensor.

[0118] In the temperature measurement of the temperature measuring instrument on the measured person, the infrared optical assembly of the temperature measuring instrument focuses the infrared radiation signal of the superficial artery measurement area on the detection surface of the infrared array sensor; the infrared array sensor converts the infrared radiation signal into an electrical signal, and then generates an initial temperature matrix after digitalization by the analog-digital converter; at the same time, the environmental temperature sensor monitors the temperature of the environment where the measured person is located to obtain an environmental temperature value.

[0119] After obtaining the initial temperature matrix and the environmental temperature value, the controller in the temperature measuring instrument processes the initial temperature matrix and performs temperature compensation through the environmental temperature value, so as to obtain the body temperature value of the measured person.

[0120] It can be understood that the non-contact measurement of the body temperature of the measured person by the temperature measuring instrument with the body temperature measurement method can reduce the inaccurate positioning of single-point measurement and the influence of the environmental temperature on the body temperature, so that the measured temperature can better reflect the actual temperature of the measured person.

[0121] Please refer to Figure 4 , Figure 4 is a flowchart for determining a body temperature value provided by an embodiment of the present application. Figure 4 In the method, the body temperature value of the measured person is determined according to the initial temperature matrix and the environmental temperature value, comprising:

[0122] S201, correcting and processing the initial temperature matrix according to the temperature compensation model and the environmental temperature value to obtain a corrected temperature matrix.

[0123] S202, determining the target superficial artery blood vessel region of the superficial artery measurement region of the measured person according to the temperature gradient feature value and the region temperature stability feature value extracted from the corrected temperature matrix.

[0124] S203, performing peak tracking processing on the corrected temperature matrix corresponding to the target superficial artery blood vessel region to determine the peak temperature value of the target superficial artery blood vessel region, and taking the peak temperature value of the target superficial artery blood vessel region as the body temperature value of the measured person.

[0125] The temperature compensation model is a mathematical model for eliminating the influence of the environmental temperature on the measurement result of the infrared sensor. By correcting and processing the initial temperature matrix through the temperature compensation model, the accuracy of the body temperature calculation can be ensured.

[0126] The temperature gradient feature value is the temperature difference between adjacent pixel points in the corrected temperature matrix, and can reflect the temperature distribution trend of the superficial artery measurement region. The region temperature stability feature value is the temperature change degree in the superficial artery measurement region over time or space, and can distinguish between dynamic (such as blood vessels) and static (such as skin) regions. The peak tracking processing is to search for the highest temperature point in the target superficial artery blood vessel region and track the position change of the highest temperature point to determine the core temperature of the superficial artery blood vessel, i.e. the peak temperature value.

[0127] Specifically, first, the initial temperature matrix is subjected to temperature correction processing by applying a temperature compensation model and an ambient temperature value to obtain a corrected temperature matrix, so as to compensate for the measurement deviation caused by the infrared array sensor and environmental factors and improve the accuracy of the basic data.

[0128] Then, the temperature gradient feature value and the region temperature stability feature value are extracted to determine the specific region of the superficial artery blood vessel in the superficial artery measurement region, i.e. the target superficial artery blood vessel region. Since the temperature gradient of the superficial artery blood vessel region is significantly higher than that of the surrounding skin due to blood flow, the superficial artery blood vessel region can be located by the temperature gradient feature value. The stability feature value will be higher than that of the surrounding skin tissue due to the temperature fluctuation caused by the blood pulse flow, so the region temperature stability feature value can be used to exclude noise interference and further locate the region of the superficial artery blood vessel. By narrowing down the superficial artery measurement region to the target superficial artery blood vessel region, the calculation complexity is reduced and the measurement accuracy is further improved.

[0129] After determining the target superficial artery blood vessel region, the corrected temperature matrix corresponding to the target superficial artery blood vessel region is subjected to peak tracking processing to obtain the peak temperature value of the target superficial artery blood vessel region, and finally the peak temperature value of the target superficial artery blood vessel region is taken as the body temperature value of the subject.

[0130] It should be understood that by locating the superficial artery blood vessel through the temperature gradient feature and the stability feature and combining peak tracking, the measurement error is reduced and the accuracy of the body temperature calculation is improved.

[0131] In step S201, the initial temperature matrix is subjected to correction processing according to a temperature compensation model and an ambient temperature value to obtain a corrected temperature matrix, including:

[0132] Based on the Gaussian filter denoising algorithm, the initial temperature matrix is subjected to filter denoising processing to obtain a filtered and denoised temperature matrix.

[0133] According to the temperature compensation model and the ambient temperature value, the ambient temperature compensation amount is calculated.

[0134] The filtered and denoised temperature matrix and the ambient temperature compensation amount are added to obtain the corrected temperature matrix.

[0135] The temperature compensation model is:

[0136] ΔT = k1(T1-T3) + k2(T2-T0) + k3(T1-T3)(T2-T0);

[0137] Wherein, ΔT is the ambient temperature compensation, T1 is the preset constant temperature unit temperature value, T2 is the ambient temperature value, T3 is the initial temperature matrix corresponding to the initial measured temperature value, T0 is the standard ambient temperature value, k1 is the first compensation coefficient, k2 is the second compensation coefficient, k3 is the third compensation coefficient.

[0138] In this embodiment, taking the measurement of the temporal superficial artery of the forehead as an example, when measuring the body temperature, the user holds the temperature measuring instrument, aligns the detection window to the measurement area of the temporal superficial artery of the forehead of the measured person, and is 3-5 cm away from the forehead surface, and performs horizontal scanning to the temple. At this time, the infrared array sensor continuously collects temperature data of different positions of the forehead, transmits to the controller, and locates the position of the temporal superficial artery and measures the temperature through a specific algorithm.

[0139] Firstly, since the initial temperature matrix collected by the infrared array sensor may contain environmental noise, such as body hair, skin wrinkles and other interference, therefore, the Gaussian filter denoising algorithm is used for smoothing processing to remove the high-frequency noise in the original data. Wherein, the initial temperature matrix is set as T m×n , m is the number of scanning rows, and n is the number of scanning columns. Assuming that the infrared array sensor is a 4*4 array, the number of scanning rows m=4, the number of scanning columns n=4, that is, the initial temperature matrix contains 4 rows and 4 columns, a total of 16 temperature values, each temperature value corresponds to the measurement result value of an infrared sensing element in the infrared array sensor, and the whole can reflect the spatial temperature distribution of the superficial artery measurement area.

[0140] It should be noted that the Gaussian filter denoising algorithm is a linear smoothing filter algorithm based on the weight of the Gaussian function, which suppresses noise by weighted average of neighborhood pixel values, while retaining the overall trend of temperature distribution.

[0141] Generally, the calculation formula of the ideal Gaussian filter denoising algorithm is as follows:

[0142] T 滤波 (x,y) = T(x,y) * G(x,y,σ);

[0143] Wherein,

[0144] In the formula, T 滤波(x, y) represents an ideal filtered temperature matrix, T(x, y) is a temperature matrix, G(x, y, σ) is a two-dimensional Gaussian function in a continuous domain, and the smoothing process in an ideal state is described. Due to the influence of the sampling frequency of the infrared array sensor in the actual scanning process, the collected data needs to be "spliced" to form a two-dimensional data matrix, therefore, the Gaussian convolution in a discrete domain is actually applied, and the Gaussian filter denoising algorithm used in the actual application is obtained through formula derivation, that is, the Gaussian filter denoising algorithm applied in the embodiment of the application, as follows:

[0145]

[0146] wherein, T 滤波 (i, j) is a temperature value of the i-th row and the j-th column in the filtered temperature matrix, (i, j) is an absolute coordinate of a target pixel in the initial temperature matrix collected by the infrared array sensor, i is a row index in the initial temperature matrix, and j is a column index in the initial temperature matrix; G(k, l) is a Gaussian kernel function, (k, l) is a relative coordinate relative to the target pixel (i, j); a and b are half window sizes; if the infrared array sensor is a 4*4 array, a=1 and b=1 in the above formula, that is, the Gaussian kernel is 3*3 (the total size in the row direction is 2a+1=3, and the total size in the column direction is 2b+1=3). At this time, the Gaussian kernel can completely cover the surrounding pixels for convolution calculation, and the smoothing filter is realized through reasonable weight distribution under the premise of not exceeding the range of the infrared array sensor, so as to retain the temperature gradient information.

[0147] It should be understood that the filtered temperature matrix obtained after the Gaussian filter denoising processing can retain the real temperature difference characteristics of the superficial arterial blood vessels and the surrounding skin, and provide more reliable basic data for subsequent feature extraction.

[0148] After the initial temperature matrix is smoothed by the Gaussian filter denoising algorithm to remove high-frequency noise in the original data and the filtered temperature matrix is obtained, the filtered temperature matrix is corrected by using a temperature compensation model and an environmental temperature value, so as to obtain a corrected temperature matrix.

[0149] It should be noted that the embodiment provides a method for constructing a temperature compensation model. First, a temperature compensation parameter experimental platform is built in a laboratory environment. In the experiment, a constant temperature unit is set, the temperature adjustment range of the constant temperature unit is set to 35.0℃-42.0℃ according to the standard of "GB / T 21416-2008 Medical Electronic Thermometer", and the constant temperature unit is used to simulate the typical fluctuation interval of the core body temperature of the human body.

[0150] During the experiment, the infrared array sensor is used to scan and measure the thermostat unit, and the following three groups of key data are collected synchronously: (1) the actual temperature value T1 of the thermostat unit. The temperature value is calibrated by a high-precision thermocouple in real time, and the precision is ±0.01℃. (2) The real-time temperature value T2 of the environment. The temperature value is collected by a negative temperature coefficient NTC thermistor, and the precision is ±0.1℃; according to the above standard, in order to meet the temperature requirements of the rated working low temperature experiment, the rated working high temperature experiment and the normal environment working condition, the environmental temperature variation interval is set to-5.0℃-50.0℃. (3) The original measurement temperature value T3 of the infrared array sensor.

[0151] By dynamically adjusting the environmental temperature (such as covering the application scene of-5.0℃-50.0℃), the actual temperature value T1 of the thermostat unit is taken in turn within the range of 35.0℃-42.0℃ with a step of 0.1℃ at each environmental temperature point, and T2 and T3 are recorded synchronously. Based on the collected massive data, a temperature compensation model is constructed, and the core formula of the temperature compensation model is as follows:

[0152] ΔT=k1(T1-T3)+k2(T2-T0)+k3(T1-T3)(T2-T0);

[0153] Wherein, ΔT is the environmental temperature compensation amount, T1 is the actual temperature value of the thermostat unit, T2 is the real-time temperature value of the environment, T3 is the original measurement temperature value of the infrared array sensor, i.e. the initial measurement temperature value corresponding to the initial temperature matrix, T0 is the standard environmental temperature value (25℃, i.e. 298.15K), k1 is the first compensation coefficient, k2 is the second compensation coefficient, and k3 is the third compensation coefficient.

[0154] Wherein, k1, k2 and k3 are compensation coefficients to be solved, which are obtained by fitting the experimental data by the least square method (wherein, the goodness of fit R 2 ≥0.99).

[0155] It should be noted that the core logic of the temperature compensation model is to minimize the sum of squares error between the theoretical calculation value and the actual observation value, so as to find the function model that best reflects the data rule. In the above temperature compensation model, k1, k2 and k3 are compensation coefficients to be determined. During the experiment, a large number of actual temperature values T1 of the thermostat unit, real-time temperature values T2 of the environment, original measurement temperature values T3 of the infrared array sensor and corresponding real environmental temperature compensation amounts ΔT 真实 =T1-T3 are collected, and the "theoretical environmental compensation amount ΔT 理论 " and the "real environmental compensation amount ΔT 真实the square difference of the sum of squares, finally, the specific values of the first compensation coefficient k1, the second compensation coefficient k2 and the third compensation coefficient k3 are determined by selecting the combination of the compensation coefficients that minimizes the total square difference, so as to ensure that the calculation result of the temperature compensation model is closest to the actual data.

[0156] wherein the goodness of fit is an index for measuring the explanation ability of the model to the actual data, and the value range is 0 to 1. The goodness of fit R 2 The closer to 1, the better the fitting effect of the model to the data, that is, the smaller the deviation between the theoretical calculation value and the actual observation value. In the experiment provided in the embodiment, the goodness of fit R 2 ≥ 0.99, indicating that the temperature compensation model provided in the embodiment can explain more than 99% of the actual measured data variation law, and only less than 1% of the error comes from the deviation of the model itself. This ensures that the compensation amount ΔT calculated by the temperature compensation model is reliable enough, and further ensures that the corrected body temperature measurement result meets the medical grade precision requirement.

[0157] A series of temperature compensation parameters calculated by the temperature compensation model can be directly used to correct the body temperature measurement result of the infrared array sensor in the actual scene, that is: T 校正 = T3 + ΔT, thereby effectively eliminating the influence of environmental temperature fluctuation on the measurement accuracy, so that the final body temperature measurement result meets the medical grade error requirement (standard specifies that the repeatability error S ≤ 0.2℃).

[0158] Therefore, through the above experiment, the final temperature compensation model is constructed, that is:

[0159] ΔT = k1(T1-T3) + k2(T2-T0) + k3(T1-T3)(T2-T0);

[0160] wherein ΔT is the environmental temperature compensation amount, T1 is the preset constant temperature unit temperature value, T2 is the environmental temperature value, T3 is the initial measurement temperature value corresponding to the initial temperature matrix, T0 is the standard environmental temperature value (usually 25℃, that is, 298.15K), k1 is the first compensation coefficient, k2 is the second compensation coefficient, and k3 is the third compensation coefficient.

[0161] In the embodiment, in view of the influence of the environmental temperature on the measurement result, the temperature compensation model needs to be combined to correct the data of the filtered and denoised temperature matrix. First, the environmental temperature compensation amount ΔT is calculated by the temperature compensation model constructed above. Then, the filtered and denoised temperature matrix T 滤波 (i,j) is added to the environmental temperature compensation amount ΔT to obtain the corrected temperature matrix T 校正 (i,j), that is, T 校正 (i,j) = T 滤波 (i,j) + ΔT.

[0162] It should be understood that the influence of environmental temperature fluctuations on the temperature difference between the superficial artery blood vessels and the skin can be effectively eliminated by data correction of the temperature matrix through the temperature compensation model and the environmental temperature value, and the accuracy of subsequent analysis and calculation can be improved.

[0163] In step S202, according to the temperature gradient feature value and the regional temperature stability feature value extracted from the corrected temperature matrix, a target superficial artery blood vessel region of the superficial artery measurement region of the subject is determined, including:

[0164] Based on the edge detection algorithm, the temperature gradient value in the horizontal direction and the temperature gradient value in the vertical direction in the corrected temperature matrix are calculated respectively, and the comprehensive temperature gradient value is obtained according to the temperature gradient value in the horizontal direction and the temperature gradient value in the vertical direction.

[0165] According to the preset temperature gradient threshold, the temperature gradient feature value is extracted from the comprehensive temperature gradient value.

[0166] Based on the sliding window algorithm, the local temperature variance value corresponding to the corrected temperature matrix in the preset sliding window is calculated.

[0167] According to the preset variance threshold, the regional temperature stability feature value is extracted from the local temperature variance value.

[0168] According to the temperature gradient feature value and the regional temperature stability feature value, the potential blood vessel boundary position of the superficial artery measurement region of the subject is determined.

[0169] Based on the adaptive threshold segmentation algorithm and the preset temperature difference value, the target superficial artery blood vessel region is determined from the potential blood vessel boundary position of the superficial artery measurement region of the subject; wherein the preset temperature difference value is the temperature difference between the superficial artery blood vessels and the surrounding skin.

[0170] It should be noted that after obtaining the corrected temperature matrix, the key features that can distinguish the superficial artery blood vessels and the surrounding skin, i.e. the temperature gradient feature value and the regional temperature stability feature value, are extracted from the corrected temperature matrix. The temperature gradient feature value and the regional temperature stability feature value extracted can determine the boundary between the superficial artery blood vessels and the surrounding skin, i.e. the potential blood vessel boundary position.

[0171] The temperature of the superficial artery at the forehead site (such as the superficial temporal artery, the supra-trochlear artery) is usually 0.8-1.2°C higher than the skin temperature of the surrounding non-vascular region; the temperature difference between the superficial artery at the neck, the back of the hand, the wrist, and the surrounding skin is slightly lower, usually 0.5-0.9°C; the temperature difference between the superficial artery at the elbow and the surrounding skin can reach 1.0-1.5°C due to the relatively thick diameter of the superficial artery (3-4 mm). Through experiments, it is concluded that the temperature difference range of 0.8-1.2°C is the typical characteristic of the temperature difference between the superficial artery and the surrounding skin, and there is a stable temperature difference between the two. Therefore, there is an obvious temperature gradient change at the junction of the superficial artery and the surrounding skin, i.e., the temperature gradient characteristic. The superficial artery region maintains a relatively constant temperature due to the continuous flow of arterial blood, with small temperature fluctuations. The superficial artery appears as a continuous high-temperature region in the temperature matrix; the temperature of the surrounding skin is easily affected by the environment, with larger temperature fluctuations, and there may be multiple isolated high-temperature points without continuity. Therefore, the superficial artery and the skin can be distinguished by the regional temperature stability characteristic. It should be understood that by analyzing the temperature gradient characteristic value and the regional temperature stability, the potential blood vessel boundary position can be preliminarily determined.

[0172] The edge detection algorithm is an image processing algorithm that detects the edges of an image by calculating the gradient approximation of each pixel point in the horizontal and vertical directions of the image. In this embodiment, the temperature gradient values of the temperature matrix in the horizontal and vertical directions are calculated by the edge detection algorithm.

[0173] The comprehensive temperature gradient value is a temperature gradient value obtained by combining the horizontal and vertical temperature gradient values, which can more comprehensively reflect the temperature changes in two-dimensional space. The preset temperature gradient threshold is a critical value for judging whether the temperature gradient value is significant. When the comprehensive temperature gradient value exceeds the preset temperature gradient threshold, it can be considered that the temperature change at this position is relatively sharp, and it is likely to be near the blood vessel boundary, thereby extracting the temperature gradient characteristic value.

[0174] The sliding window algorithm is an algorithm that moves a fixed-size window over a data matrix and processes the data in the window. In this embodiment, the sliding window algorithm can be used to calculate the temperature variance value of the local region of the corrected temperature matrix. The preset sliding window is a window that is moved in the corrected temperature matrix, and the size of the preset sliding window is not limited in this embodiment. The local temperature variance value is a value that reflects the degree of temperature fluctuation in the local region covered by the sliding window. The larger the variance, the more unstable the temperature change in the region. The preset variance threshold is a critical value for judging whether the local temperature variance value is significant. When the local temperature variance value exceeds the threshold, it can be considered that the temperature stability of the region is poor, and it is likely to be near the blood vessel boundary, thereby extracting the regional temperature stability characteristic value.

[0175] Specifically, the edge detection algorithm is used to calculate the comprehensive temperature gradient value, the edges of temperature change are detected by applying specific convolution kernels in the horizontal direction (i.e. x direction) and the vertical direction (i.e. y direction), so as to capture the temperature difference boundary between the superficial artery and the surrounding skin, and the boundary features of the blood vessels and the skin can be effectively extracted, and the formula is as follows:

[0176] W x (i,j) = [T 校正 (i-1,j+1) + K·T 校正 (i,j+1) + T 校正 (i+1,j+1)] - [T 校正 (i-1,j-1) + K·T 校正 (i,j-1) + T 校正 (i+1,j-1)].

[0177] W y (i,j) = [T 校正 (i+1,j-1) + K·T 校正 (i+1,j) + T 校正 (i+1,j+1)] - [T 校正 (i-1,j-1) + K·T 校正 (i-1,j) + T 校正 (i-1,j+1)].

[0178] Wherein, W x (i,j) is the temperature gradient value in the horizontal direction; W y (i,j) is the temperature gradient value in the vertical direction; K is the weight coefficient; T 校正 (i-1,j+1) is the temperature value corresponding to the pixel in the i-1th row and the j+1th column of the corrected temperature matrix; T 校正 (i,j+1) is the temperature value corresponding to the pixel in the i row and the j+1th column of the corrected temperature matrix; T 校正 (i+1,j+1) is the temperature value corresponding to the pixel in the i+1th row and the j+1th column of the corrected temperature matrix; T 校正 (i-1,j-1) is the temperature value corresponding to the pixel in the i-1th row and the j-1th column of the corrected temperature matrix; T 校正 (i,j-1) is the temperature value corresponding to the pixel in the i row and the j-1th column of the corrected temperature matrix; T 校正 (i+1,j-1) is the temperature value corresponding to the pixel in the i+1th row and the j-1th column of the corrected temperature matrix; T 校正 (i+1,j) is the temperature value corresponding to the pixel in the i+1th row and the j column of the corrected temperature matrix; T 校正(i-1,j) is a temperature value corresponding to the pixel in the i-1th row and jth column in the corrected temperature matrix.

[0179] The temperature change rates in the horizontal and vertical directions are obtained by weighting calculation and difference calculation of the above formula. When the weight coefficient K is set to 2 for the 4x4 infrared array sensor, the calculation is ensured within a limited pixel range, the overall recognition accuracy is ensured, and the temperature values near the center have a greater impact on the gradient result (the center pixel has the strongest correlation with the temperature of its positive neighborhood, i.e. the temperature of the positive right and the positive left, and has the greatest contribution to the gradient change).

[0180] Then, the comprehensive temperature gradient value W(i,j) is calculated by the following formula:

[0181]

[0182] In the boundary area of blood vessels and skin, due to the existence of a temperature difference of 0.8-1.2℃, the value of W(i,j) will be significantly greater than that in other areas, and the greater the temperature gradient change, the greater the value of W(i,j).

[0183] Since the blood flow in the superficial arterial blood vessels is relatively stable, the temperature change is relatively small (i.e. the temperature variance value is small); and the surrounding skin is affected by environmental factors (such as air flow, body surface heat dissipation, etc.), and the temperature fluctuation is large (i.e. the temperature variance value is large), and the local temperature variance value is calculated by using the sliding window algorithm, so as to further distinguish the blood vessel area and the surrounding skin area. The specific calculation formula is:

[0184]

[0185] wherein, σ 2 (i,j) is the local temperature variance value, w x h is the size of the preset sliding window, (k,l) is the offset coordinates of the pixels in the preset sliding window relative to the target pixel (i,j), T 校正 (k,l) is a temperature value corresponding to the pixel (k,l) in the corrected temperature matrix. In order to balance the local temperature stability analysis and the area coverage range, it is necessary to ensure that the preset sliding window can cover a larger space than the array itself, so as to capture the continuous temperature distribution characteristics of the blood vessels, and avoid cutting the blood vessel area due to the limitation of the array size, such as selecting a 4x4 infrared array sensor, setting w=5, h=5, i.e. a 5x5 sliding window.

[0186] T 平均 (i,j) is the average temperature value in the preset sliding window, which can be calculated by the following formula:

[0187]

[0188] By calculating the temperature variance value of a specific area, i.e. σ 2(i,j) can reflect the discrete degree of the temperature data in the preset sliding window centered at (i,j). The temperature fluctuation of the superficial artery is small because the core temperature blood flows through it, and the corresponding σ 2 (i,j) value is significantly low; while the surrounding skin is directly exposed to the environment, and is affected by external temperature, airflow, etc., the temperature is prone to fluctuation, and the σ 2 (i,j) value of the corresponding region is relatively high.

[0189] When the combined temperature gradient value W(i,j) of a region is greater than a preset temperature gradient threshold, and the temperature variance value σ 2 (i,j) of the region is less than a preset variance threshold, it can be determined that the region is a superficial artery region. That is, if a region simultaneously satisfies the "high gradient value" and "low variance value", the region can be more accurately determined as a superficial artery region, thereby reducing the misjudgment rate of single feature judgment. By analyzing the temperature gradient value and the regional temperature stability feature value, the potential blood vessel boundary position can be preliminarily determined. In this embodiment, the specific numerical values of the preset temperature gradient threshold and the preset variance threshold are not limited.

[0190] After determining the potential blood vessel boundary position of the superficial artery measurement region of the subject, a high temperature region is extracted from the potential blood vessel boundary position of the superficial artery measurement region of the subject according to the adaptive threshold segmentation algorithm and a preset temperature difference value, so as to determine the target superficial artery blood vessel region.

[0191] The adaptive threshold segmentation algorithm is an algorithm that dynamically adjusts the segmentation threshold according to the local image characteristics, and can extract the blood vessel region with a temperature higher than the surrounding skin from the potential blood vessel boundary. The preset temperature difference value is the temperature difference between the superficial artery blood vessel and the surrounding skin of the blood vessel, which is usually 0.8-1.2°C.

[0192] It should be understood that by adapting to local temperature changes through adaptive threshold, under-segmentation or over-segmentation caused by global threshold is avoided, and the superficial artery blood vessel region is further accurately determined.

[0193] In one possible implementation, the target superficial artery blood vessel region is determined from the potential blood vessel boundary position of the superficial artery measurement region of the subject based on the adaptive threshold segmentation algorithm and the preset temperature difference value, comprising:

[0194] The arithmetic mean and the standard deviation of the corrected temperature matrix are calculated.

[0195] The dynamic temperature threshold is calculated according to the arithmetic mean and the standard deviation of the corrected temperature matrix, and the preset temperature difference value.

[0196] The region with a temperature value greater than the dynamic temperature threshold in the corrected temperature matrix is determined as the target superficial artery blood vessel region.

[0197] According to the temperature difference between the arterial blood vessels and the surrounding skin (0.8-1.2°C temperature difference), a self-adaptive threshold segmentation algorithm is used to extract the high temperature area, i.e. the target superficial arterial blood vessel area. The specific implementation steps are as follows:

[0198] First, the corrected temperature matrix T 校正 (i,j) is calculated.

[0199] The arithmetic mean μ is the average of all pixel temperature values in the corrected temperature matrix, reflecting the overall temperature concentration trend, and the calculation formula is:

[0200]

[0201] Where m x n is the array size of the infrared array sensor (for example, when the infrared array sensor is a 4 x 4 array, m = 4, n = 4, and the total number of pixels is 16); T 校正 (i,j) is the temperature value corresponding to the i-th row and j-th column pixel in the corrected temperature matrix.

[0202] The standard deviation γ is used to measure the dispersion of all pixel temperature values in the temperature matrix, i.e. the uniformity of temperature distribution, and the calculation formula is as follows:

[0203]

[0204] Where μ is the arithmetic mean; [T 校正 (i,j)-μ] 2 represents the square of the deviation of the temperature value of a single pixel from the arithmetic mean, and by summing and averaging and then taking the square root, the dispersion of the overall temperature is obtained.

[0205] Then, the dynamic temperature threshold T 阈值 is calculated by the formula: T 阈值According to the experimental data, the threshold coefficient k4 is set, and the value of k4 is usually between 1.5 and 2. The standard deviation value γ of the corrected temperature matrix reflects the temperature dispersion degree of the superficial artery region, and in a normal measurement scenario, the standard deviation value γ is usually stable at 0.3-0.6℃, which is the statistical data of the experimental data. When k4=1.5, the threshold offset is 1.5γ, which corresponds to an actual temperature difference of about 0.45-0.9℃; when k4=2, the threshold offset is 2γ, which corresponds to an actual temperature difference of about 0.6-1.2℃. In order to ensure that the selected high-temperature region contains complete superficial arteries and meets the accuracy standard of medical-grade electronic thermometers in GB / T 21416-2008 Medical Electronic Thermometers, the error S≤0.2℃, and here the value of k4 is 1.8, the threshold offset is 1.8γ, which corresponds to an actual temperature difference of about 0.54-1.08℃. It not only avoids the truncation of the blood vessel region due to the too small threshold coefficient, but also prevents the introduction of too much skin region interference due to the too large threshold coefficient. For example, experimental data shows that when k4=1.8, the recognition accuracy of the adaptive threshold segmentation on the superficial temporal artery region can reach more than 98%, and the compatibility with the subsequent connected component analysis and peak tracking algorithm is the best, and the final body temperature measurement error can be controlled within 0.2℃.

[0206] Finally, the T 校正 (i,j)≥T 阈值 region, which is the selected target superficial artery blood vessel region. Due to the interference of the environment temperature and the individual differences of the measured object, the threshold coefficient k4 will be adaptively adjusted with the real-time standard deviation value γ and the environment temperature T2, that is, the threshold is dynamically adjusted. It ensures that the device dynamically adjusts the threshold according to the real-time environment and individual characteristics at each measurement, so as to accurately identify the superficial artery region and provide a reliable basis for subsequent body temperature calculation.

[0207] In step S203, the corrected temperature matrix corresponding to the target superficial artery blood vessel region is subjected to peak tracking processing to determine the peak temperature value of the target superficial artery blood vessel region, and the peak temperature value of the target superficial artery blood vessel region is taken as the body temperature value of the measured person, including:

[0208] The corrected temperature matrix corresponding to the target superficial artery blood vessel region is unfolded along the column direction by row to obtain a plurality of one-dimensional temperature curves.

[0209] Each one-dimensional temperature curve is subjected to three-point sliding window processing to determine the peak temperature point of each one-dimensional temperature curve and the peak temperature value corresponding to the peak temperature point of each one-dimensional temperature curve.

[0210] According to the peak temperature value corresponding to the peak temperature point of each one-dimensional temperature curve, the peak temperature value of the target superficial artery blood vessel region is determined, and the peak temperature value of the target superficial artery blood vessel region is taken as the body temperature value of the measured person.

[0211] The core of the peak tracking algorithm is to locate the blood vessel center by analyzing the local features of the temperature curve, i.e. the area covered by the continuous peak points. These peak points correspond to the highest temperature of the superficial arterial blood vessel center. After the pre-processing of noise reduction, data correction, feature extraction and adaptive threshold segmentation, the superficial arterial region has been accurately locked, and the temperature of the blood vessel center finally captured by the peak tracking algorithm is the measurement result that can be used to represent the body temperature of the human body. The specific process is as follows:

[0212] The corrected temperature matrix T 校正 (i,j) is unfolded along the horizontal direction (scanning direction, i.e. column direction j) to obtain a plurality of one-dimensional temperature curves, i.e.

[0213] T 曲线i (j) = T 校正 (i,j), (i = 1, 2, …, m; j = 1, 2, …, n);

[0214] Wherein, i is the row index of the corrected temperature matrix (corresponding to different infrared sensing elements of the infrared array sensor), j is the column index of the corrected temperature matrix (horizontal scanning position), m x n is the array size (such as m = 4, n = 4 in a 4 x 4 infrared array sensor). For each one-dimensional temperature curve T 曲线i (j), a three-point sliding window (i.e. covering j-1, j, j+1) is used, if the following conditions are met:

[0215] T 曲线i (j) > T 曲线i (j-1);

[0216] T 曲线i (j) > T 曲线i (j+1);

[0217] T 曲线i (j) - T 曲线i (j-1) ≥ 0.8℃;

[0218] T 曲线i (j) - T 曲线i (j+1) ≥ 0.8℃;

[0219] Then determine that j is the peak point of the one-dimensional temperature curve, and the coordinate value corresponding to the peak point is (i,j).

[0220] Through the above method, the output is the blood vessel center trajectory coordinate set {(i1,j1),(i2,j2),…,(i n ,j n )} and the corresponding temperature values {T1,T2,…,T n}, wherein T1 is the temperature value corresponding to the peak point (i1,j1), T2 is the temperature value corresponding to the peak point (i2,j2), and Tn is the temperature value corresponding to the peak point (i n n The set of coordinates of the blood vessel center trajectory reflects the continuous direction of the superficial artery in the transverse scanning range. Finally, the temperature value corresponding to the set of coordinates of the blood vessel center trajectory is weighted or averaged to determine the peak temperature value of the target superficial artery blood vessel region, which represents the true temperature of the blood vessel center, i.e., the body temperature of the subject.

[0221] It should be noted that in some examples, after obtaining the target superficial artery blood vessel region, the binary matrix of the target superficial artery blood vessel region can be further analyzed based on morphological operation to further determine the superficial artery blood vessel region. Specifically, it includes:

[0222] The binary matrix of the target superficial artery blood vessel region is processed by the dilation operation formula to fill the gap, and the isolated noise points in the binary matrix of the target superficial artery blood vessel region are removed by the erosion operation formula to obtain an optimized binary matrix;

[0223] The areas of multiple connected domains in the optimized binary matrix are calculated, and the optimized superficial artery blood vessel region is determined from the multiple connected domain areas according to a preset pixel value.

[0224] The superficial artery blood vessel is a continuous tubular structure under the human epidermis. The binary image after threshold segmentation is processed by morphological operation, which can remove isolated high-temperature noise points and retain continuous blood vessel regions. This stage mainly involves two morphological operations of dilation and erosion, which are based on a binary matrix (set as A, where "1" represents a foreground pixel and "0" represents a background pixel) and a structure element (set as B, since the above 4x4 infrared array sensor is selected, the structure element is set to 3x3, which can effectively fill the small gap in the blood vessel region and will not over-expand the blood vessel boundary).

[0225] It should be noted that in this embodiment, if the temperature measuring instrument uses a 4x4 infrared array sensor, the structure element used in the morphological operation in this embodiment is a 3x3 square structure element (the element matrix is where "1" represents the pixel area covered by the structure element). The basis for selecting a 3x3 square structure element is as follows:

[0226] ​(1) Matching the resolution of the infrared array sensor. The temperature measuring instrument of the embodiment adopts a 4x4 infrared array sensor, the detection range of a single sensing element thereof is 2mm-3mm, and the overall measurement area is 8mm-12mm; the projection width of the superficial artery blood vessel on the body surface is 5mm-8mm (such as the forehead temporal superficial artery), the actual spatial coverage range corresponding to the 3x3 square structure element is 6mm-9mm (wherein the coverage range corresponding to a single structure element pixel is 2mm-3mm), which can completely cover the blood vessel cross section, avoid the blood vessel gap being unable to be filled due to the structure element being too small (such as a 2x2 square structure element), or the blood vessel boundary being excessively expanded and mixed into the surrounding skin area due to the structure element being too large (such as a 4x4 square structure element).

[0227] (2) Balancing noise removal and blood vessel integrity. Experimental verification shows that when the structure element size is less than 3x3 (such as 2x2), although small isolated noise points (diameter ≤2mm) can be removed, small gaps (width 1mm-2mm) in the blood vessel area caused by hair obstruction and skin wrinkles cannot be filled, resulting in the blood vessel area being broken; when the structure element size is greater than 3x3 (such as 4x4), although the gap can be filled, the skin area 1mm-2mm around the blood vessel is misjudged as part of the blood vessel, resulting in distortion of the blood vessel area profile. The 3x3 square structure element can achieve a balance between “removing isolated noise points with a diameter of ≤3mm” and “filling blood vessel gaps with a width of ≤2mm”, ensuring that the optimized blood vessel area is complete and free of redundant interference.

[0228] In order to verify the effectiveness of the 3x3 square structure element when the temperature measuring instrument adopts a 4x4 infrared array sensor, in this embodiment, 50 healthy subjects (aged 20-60 years old, 25 males and 25 females) can be selected for measurement in the forehead temporal superficial artery and neck superficial artery regions, and the optimization effects of different structure element sizes can be compared. As shown in Table 1, Table 1 shows the optimization effect of structure elements of different sizes. As can be seen from Table 1, the 3x3 structure element has the best comprehensive performance in the three indicators of “blood vessel area integrity”, “noise removal rate” and “size deviation”, which meets the requirement of the temperature measuring instrument for the positioning accuracy of the superficial artery area (deviation ≤0.2mm), and therefore, when the temperature measuring instrument adopts a 4x4 infrared array sensor, the 3x3 square structure element is determined as the optimal structure element parameter.

[0229] Table 1 Optimization effect of structure elements of different sizes

[0230] Structural element size Vessel region integrity (continuity rate) Noise removal rate Deviation from actual vessel size 2×2 82% (18% appeared to be broken) 95％ ≤ 0.2 mm 3×3 98% (2% appeared to have a small gap) 92％ ≤ 0.1 mm 4×4 100% (no breakage) 85％ 0.3 mm - 0.5 mm

[0231] Specifically, the dilation operation (gap filling) formula is:

[0232]

[0233] where p is the pixel coordinate in binary matrix A, representing the position of any pixel in binary matrix A. For each pixel in binary matrix A, if there is at least one "1" in its neighborhood (defined by structure element B), the pixel is marked as "1". Through dilation, small gaps in the blood vessel region can be filled, and discontinuous blood vessel fragments can be connected into a complete region.

[0234] The formula for the erosion operation (removing burrs) is:

[0235]

[0236] For each pixel in binary matrix A, if all pixels in its neighborhood (defined by structure element B) are "1", the pixel is retained as "1", otherwise it is marked as "0". Through erosion, isolated noise points (such as burrs) on the edge of the blood vessel region can be removed, optimizing the shape of the blood vessel.

[0237] In this embodiment, a dilation operation is performed once, i.e. a 3x3 square structure element is used to traverse the binary matrix ("1" represents foreground pixels, i.e. target blood vessel region, "0" represents background pixels). If there is at least one "1" foreground pixel in the coverage of the structure element, the center pixel is marked as "1", which fills the small gaps (i.e. one pixel gap) in the blood vessel region and connects the broken blood vessel fragments into a continuous region. In this embodiment, the number of dilation operations is limited to one, and if it is performed twice or more, it will cause the blood vessel region boundary to expand outward beyond 0.5mm, increasing the deviation from the actual blood vessel size.

[0238] After the dilation operation, a second erosion operation is performed, i.e. the same 3x3 square structure element is used to traverse the dilated binary matrix. Only when all pixels in the coverage of the structure element are "1", the center pixel is retained as "1", otherwise it is marked as "0". This can remove the edge burrs (such as isolated noise points of 1 pixel around the blood vessel) introduced in the dilation operation and restore the true profile of the blood vessel. The number of erosion operations is consistent with the number of dilation operations, i.e. both are once, to avoid excessive contraction of the blood vessel region (contraction amplitude ≤0.3mm) due to excessive erosion, and to ensure that the core region of the blood vessel is not lost.

[0239] After morphological processing of "dilation and erosion", the output is an optimized binary matrix, i.e. the continuous "1" region represents the optimized shallow arterial blood vessel region after screening, and the "0" region represents the background (skin or noise). At the same time, by calculating the connected domain area (counting the number of pixels in each continuous "1" region), the connected domain with a reasonable area (usually 5-30 pixels) is retained, and the regions that are too large (may contain non-blood vessel tissue) or too small (may be noise) are excluded. As shown in Figure 5 Figure 5 ​is a schematic diagram of an effect of morphological processing on a target superficial arterial blood vessel region according to an embodiment of the present application. As shown in Figure 6 Figure 6 is a schematic diagram of an effect of morphological processing on a target superficial arterial blood vessel region according to an embodiment of the present application. As shown in Figure 5 Figure 6 It can be seen that, after morphological processing, isolated noise points are removed and the blood vessel morphology becomes more complete.

[0240] It should be noted that, in the present embodiment, connected component analysis can or can not be performed, which can be determined according to actual conditions.

[0241] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0242] A body temperature measurement method corresponding to the above embodiment, Figure 7 shows a structural schematic diagram of a body temperature measurement device according to an embodiment of the present application. For ease of illustration, only parts related to the embodiments of the present application are shown.

[0243] Referring to Figure 7 , the body temperature measurement device 3 of the present embodiment is applied to the temperature measuring instrument 1 of any one of the above embodiments, and the device 3 comprises:

[0244] The acquisition module 31 is configured to acquire an initial temperature matrix corresponding to an infrared radiation signal of a superficial arterial measurement region of a subject and an environmental temperature value of an environment in which the subject is located.

[0245] The determination module 32 is configured to determine a body temperature value of the subject according to the initial temperature matrix and the environmental temperature value.

[0246] It should be noted that the information interaction, execution process, etc. between the modules in the above body temperature measurement device 3, since based on the same concept as the method embodiments of the present application, the specific functions and the technical effects brought by them can be referred to the method embodiments part, and will not be repeated here.

[0247] The present embodiment further provides a terminal device, as shown in Figure 8 Figure 8 is a structural schematic diagram of a terminal device according to an embodiment of the present application. Referring to Figure 8 , the terminal device 4 of the present embodiment comprises a memory 41, a processor 42, and a computer program stored in the memory 41 and executable on the processor 42, and the processor 42 implements the steps in the body temperature measurement method embodiments of any one of the above embodiments when executing the computer program. ​​​

[0248] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to realize the steps in the above-mentioned various method embodiments.

[0249] The embodiment of the present application provides a computer program product. When the computer program product is run on a mobile terminal, the mobile terminal is caused to execute the steps in the above-mentioned various method embodiments.

[0250] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the present application realizes all or part of the processes in the above-mentioned embodiment methods, which can be completed by instructing related hardware through a computer program. The computer program can be stored in a computer readable storage medium. The computer program, when executed by a processor, can realize the steps in the above-mentioned various method embodiments. The computer program includes computer program code, which can be in the form of source code, object code, executable file or some intermediate form. The computer readable medium at least includes any entity or device capable of carrying the computer program code to the photographing device / terminal equipment, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium. For example, U disk, mobile hard disk, magnetic disk or optical disk, etc. In some jurisdictions, according to legislation and patent practice, the computer readable medium cannot be an electrical carrier signal and a telecommunication signal.

[0251] In the above-mentioned embodiments, the description of each embodiment has its own focus. The parts not described or recorded in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0252] Those skilled in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0253] In the embodiments provided by the present application, it should be understood that the disclosed apparatus / network device and method can be implemented in other manners. For example, the embodiments of the apparatus / network device described above are merely illustrative. For example, the division of the modules or units is merely logical function division, and there can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections between the units can be indirect couplings or communication connections through some interfaces, devices or units, and can be electrical, mechanical or in other forms.

[0254] The units described as separated components can or can not be physically separated, and the components displayed as units can or can not be physical units, i.e., can be located in one place or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments of the present application.

[0255] The above embodiments are merely used to describe the technical solutions of the present application, but not limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalent replacements; and these modifications or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A temperature measuring instrument, characterized in that, include: The device comprises a housing, an infrared array sensor, an ambient temperature sensor, a controller, and a display, wherein the infrared array sensor, the ambient temperature sensor, and the controller are all disposed inside the housing. The infrared array sensor, connected to the controller, is used to collect infrared radiation signals from the superficial artery measurement area of ​​the subject, convert the infrared radiation signals into an initial temperature matrix, and send the initial temperature matrix to the controller. The ambient temperature sensor is connected to the controller and is used to collect the ambient temperature value of the environment where the subject is located, and send the ambient temperature value to the controller; The controller, connected to the display, is used to receive the initial temperature matrix and the ambient temperature value, and to determine the body temperature value of the subject based on the initial temperature matrix and the ambient temperature value. The display, disposed on the surface of the housing, is used to display the body temperature value.

2. The thermometer as described in claim 1, characterized in that, The housing is provided with a detection part facing the superficial artery measurement area of ​​the subject, and an infrared optical component is provided at the open end face of the detection part; The infrared optical component is used to focus the infrared radiation signal from the superficial artery measurement area of ​​the subject onto the detection surface of the infrared array sensor, so that the infrared array sensor can collect the infrared radiation signal.

3. The temperature measuring instrument as described in claim 2, characterized in that, The infrared optical component is a superlens.

4. A method for measuring body temperature, characterized in that, Applied to the thermometer as described in any one of claims 1-3, the method comprises: The initial temperature matrix corresponding to the infrared radiation signal of the superficial artery measurement area of ​​the subject and the ambient temperature value of the environment where the subject is located are obtained. The subject's body temperature is determined based on the initial temperature matrix and the ambient temperature value.

5. The body temperature measurement method as described in claim 4, characterized in that, The acquisition of the initial temperature matrix corresponding to the infrared radiation signal of the superficial artery measurement area of ​​the subject and the ambient temperature value of the environment where the subject is located includes: Infrared radiation signals from the superficial artery measurement area of ​​the subject, focused by the infrared optical component, are acquired by an infrared array sensor, and the infrared radiation signals are converted into the initial temperature matrix by the infrared array sensor. The ambient temperature value of the environment in which the subject is located is collected by an ambient temperature sensor.

6. The body temperature measurement method as described in claim 4, characterized in that, Determining the subject's body temperature based on the initial temperature matrix and the ambient temperature value includes: Based on the temperature compensation model and the ambient temperature value, the initial temperature matrix is ​​corrected to obtain the corrected temperature matrix. Based on the temperature gradient feature value and regional temperature stability feature value extracted from the corrected temperature matrix, the target superficial artery vascular region of the subject's superficial artery measurement area is determined. Peak tracking processing is performed on the corrected temperature matrix corresponding to the target superficial artery region to determine the peak temperature value of the target superficial artery region, and the peak temperature value of the target superficial artery region is used as the body temperature value of the subject.

7. The body temperature measurement method as described in claim 6, characterized in that, The step of correcting the initial temperature matrix based on the temperature compensation model and the ambient temperature value to obtain the corrected temperature matrix includes: Based on the Gaussian filtering noise reduction algorithm, the initial temperature matrix is ​​filtered and denoised to obtain the filtered and denoised temperature matrix. The ambient temperature compensation amount is calculated based on the temperature compensation model and the ambient temperature value. The filtered and denoised temperature matrix is ​​added to the ambient temperature compensation amount to obtain the corrected temperature matrix; wherein, the temperature compensation model is: ΔT=k1(T1-T3)+k2(T2-T0)+k3(T1-T3)(T2-T0); Wherein, ΔT is the ambient temperature compensation amount, T1 is the preset constant temperature unit temperature value, T2 is the ambient temperature value, T3 is the initial measured temperature value corresponding to the initial temperature matrix, T0 is the standard ambient temperature value, k1 is the first compensation coefficient, k2 is the second compensation coefficient, and k3 is the third compensation coefficient.

8. The body temperature measurement method as described in claim 7, characterized in that, The step of determining the target superficial artery region of the subject's superficial artery measurement area based on the temperature gradient feature values ​​and regional temperature stability feature values ​​extracted from the corrected temperature matrix includes: Based on the edge detection algorithm, the horizontal and vertical temperature gradient values ​​in the corrected temperature matrix are calculated respectively, and the comprehensive temperature gradient value is obtained based on the horizontal and vertical temperature gradient values. Based on a preset temperature gradient threshold, the temperature gradient feature value is extracted from the comprehensive temperature gradient value. Based on the sliding window algorithm, the local temperature variance value corresponding to the corrected temperature matrix within the preset sliding window is calculated. Based on a preset variance threshold, the regional temperature stability feature value is extracted from the local temperature variance value. Based on the temperature gradient characteristic value and the regional temperature stability characteristic value, the potential vascular boundary location of the superficial artery measurement area of ​​the subject is determined; Based on an adaptive threshold segmentation algorithm and a preset temperature difference value, the target superficial artery region is determined from the potential vascular boundary location of the superficial artery measurement area of ​​the subject; wherein, the preset temperature difference value is the temperature difference between the superficial artery and the skin surrounding the vessel.

9. The body temperature measurement method as described in claim 8, characterized in that, The method of determining the target superficial artery region from the potential vascular boundary location of the superficial artery measurement area of ​​the subject based on an adaptive threshold segmentation algorithm and a preset temperature difference value includes: The arithmetic mean and standard deviation of the corrected temperature matrix are calculated. The dynamic temperature threshold is calculated based on the arithmetic mean and standard deviation of the corrected temperature matrix and the preset temperature difference value. The region in the corrected temperature matrix whose temperature value is greater than the dynamic temperature threshold is identified as the target superficial arterial vessel region.

10. The body temperature measurement method as described in claim 9, characterized in that, The step of performing peak tracking processing on the corrected temperature matrix corresponding to the target superficial artery region to determine the peak temperature value of the target superficial artery region, and using the peak temperature value of the target superficial artery region as the body temperature value of the subject, includes: The corrected temperature matrix corresponding to the target superficial arterial vessel region is expanded along the column direction by rows to obtain multiple one-dimensional temperature curves. A three-point sliding window process is performed on each of the one-dimensional temperature curves to determine the peak temperature point of each one-dimensional temperature curve and the peak temperature value corresponding to the peak temperature point of each one-dimensional temperature curve. Based on the peak temperature value corresponding to the peak temperature point of each of the one-dimensional temperature curves, the peak temperature value of the target superficial artery region is determined, and the peak temperature value of the target superficial artery region is used as the body temperature value of the subject.

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