TECHNICAL FIELD
rOOOll This invention relates to a method to measure the core body temperatures of multiple warm-blooded subjects like humans or animals by using a combination of thermal and optical images.
BACKGROUND
[0002] This background description includes some information that is useful in understanding the present invention, its necessity and its advantages.
[0003] At present, many parts of the world are threatened with a new influenza which is highly contagious, widely prevalent and has a high incidence and death rate. The scale of this infection is a serious threat to worldwide human health social stability and economic development.
[0004] It is an influenza which causes serious respiratory problems and can be spread intentionally or unintentionally by travelers going through public transit and other public areas like airports, train stations, metro stations, grocery stores, and the streets in general. As of writing this there are more than 1 million confirmed cases of the COVID-19 virus and more than 50,000 confirmed deaths directly because of this. COVID-19 most likely spreads from person to person contact or direct contact with infected surfaces or substances. For example a healthy person can get infected, if an infected person sneezes in his/her vicinity or the healthy person touches a surface which has been touched by an infected person, and thereafter the healthy person touches his/her eyes,nose or mouth.
[0005] While most medical organizations around the world work round the clock to find a cure or a vaccine to this influenza, it is imperative that governments and institutions take effective measures to reduce or prevent its spread among the populace. For this to happen an effective screening solution must exist to identify the symptoms of this infection and to isolate the people infected to prevent the further spread of the influenza virus. Most standard diagnostic techniques are time consuming and not suitable for areas which see a higher footfall of people including public transit and other public places. Hence a new screening technique is needed which can analyse humans at a massive scale and be accurate at doing so.
[0006] Early symptoms of COVID-19 virus are high body temperature (fever), tiredness, dry cough. Of these high body temperature is the easiest to detect from a distance, and hence is used as the most common early screening method by public authorities and medical professionals alike. High body temperature is a symptom of many other diseases also, and as such may be useful in screening for other infectious diseases like SARS, he bola, typhoid, tuberculosis, chickenpox.

[0007] There are multiple ways of measuring the body temperature of an individual most of which are not suitable for mass screening of humans. Most common temperature measurement technique is using either oral, rectal or axillary methods. These methods, although accurate, typically take 2 to 3 minutes to produce results, and are contact based which means that they carry a high risk of spreading the infection due to the contact of surfaces and humans involved. The oral body temperature is usually around 37° C (98.6° F)
[0008] Another method of high-temperature screening is using infrared thermometers that are pointed to the forehead of individuals to take the temperature measurement of the skin surface. This process is shorter than the clinical method described above, but also takes around 10 seconds to produce a result. It is also not suitable when temperature measurement of a crowd of people is to be taken because it requires the operator to physically go to the individual to take the measurement which is tedious and might not be affective where there is a large number of people involved.
[0009] Another more advanced method of temperature measurement is using an infrared thermal camera which typically produces a temperature measurement at 10Hz. In this case even though the temperature measurement is happening quite fast it still is not an effective screening device for crowds or fast moving people because it requires the individuals to follow a certain procedure to get their temperatures taken, which might not always be followed. In addition this method cannot be used to simultaneously screen a crowd of people not following a certain pattern as is the case with most public spaces. Even if such devices are used in public spaces there arises a problem of attribution of high-temperature to a certain individual just because of the presence of multiple individuals in the scene when an alarm was generated. In addition these types of devices require a trained professional to operate them which might be a limiting factor in a public health crisis such as COVID-19 where there is already a shortage of medical staff.
[0010] Hence an invention is needed to detect high body temperatures of individuals in a crowded or a fast moving environment where it is possible to attribute the high body temperature alarm to a specific person. An invention can be an effective tool at screening people who might have an infectious disease and hence by examining the person further spread might be controlled.
[0011] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0012] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term "about." Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some

embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0013] As used in the description herein and throughout the claims that follow, the meaning of "a," "an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.
[0014] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification 4 as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. "such as") provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0015] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.
OBJECTS OF THE INVENTION
[0016] It has already been proposed that thermal imaging techniques are a useful way to measure core body temperatures of subjects in a non-invasive and remote way. Existing techniques use a trained professional to follow a certain set of directions and the subject to also follow another set of directions (such as walking on the fixed path) and are limited in the sense that they can only measure one subject at a time.
[0017] The principal object of this invention is to establish a method using which core body temperatures of multiple subjects can be monitored and don't need either the subject or the operator to follow and special directions. This leads to increased usability for monitoring core body temperatures to detect conditions like fever, hypothermia etc which might be a symptom of a much more infectious disease like COVID-19 in order to screen such individuals to prevent further spread of infection.

[0018] Another object of this invention is to enable core body temperature measurements quickly, non-invasively and remotely. This is useful in preventing the spread of virus by enabling two bodies to remain far apart.
SUMMARY
[0019] The summary described below is intended as a description of various implementations and is not intended to represent the only implementation described below. The description, summary and drawing are to be regarded as illustrative in nature and not restrictive.
[0020] This described invention presents a method for obtaining accurate measurements of core body temperature of multiple people, quickly, non-invasively, and remotely. The core methodology used in this invention is the usage of optical images and thermal images in tandem with each other where optical images are used to detect humans and subsequently their skin temperatures from relevant areas are taken through thermal images. Once raw skin temperatures are measured, core body temperature can be measured with the use of some simple calculations and algorithms.
[0021] The invention consists of a thermal sensor, an optical sensor, a signal processor and an enclosure in most embodiments. However, some embodiments of the invention might include more components while keeping the same general methodology. Some embodiments of the invention might also include different placements of the components while keeping the same general methodology.
[0022] The methodology followed in the invention it is a broad description of the steps that are followed to obtain the desired results however the order of the steps might be interchanged or a few steps removed or added without changing the object of this invention. The summary of the methodology is given as follows : First, the signal processor simultaneously fetches the images from an optical sensor and a thermal sensor. Then correction and calibration according to the physical properties of the sensors are applied in the processor in order to make sure that the Field of View (FOV) of the cameras are the same before any further processing is done. A machine learning algorithm is run by the signal processor on the optical image to detect the faces of all the human subjects present in the scene of the image. According to the group of pixels representing the face of a subject, corresponding group of pixels are obtained from the thermal image, in which each pixel value represents the temperature of the surface represented by the pixel. The average of the highest 5 pixel temperature values are taken from a group of pixels obtained form the forehead of the detected face in the previous step. An offset of 0.7 deg C is added to the value obtained in the previous step to represent the difference between the core body temperature and the forehead skin surface temperature. The steps described above are run by the signal processor repeatedly generating a video or can be run once. This enables accurate temperature measurements quickly, remotely and non-invasively.
[0023] Once the core body temperature is obtained from the process described in para 0022, in some embodiments, the core body temperature is compared against a predetermined threshold of 38 degC above which a body is said to have a higher than

normal temperature indicating fever, according to the prevailing medical wisdom. If the core body temperature is found to be higher than the threshold, an immediate alert is generated on the display unit to enable to operator to take action.
[0024] In an embodiment, the core body temperature can be displayed on a display unit along with indications of body temperature to its respective subject.
[0025] In an embodiment upper and/or lower temperature threshold can be set according to which alert can be displayed on a display unit and/or an audio unit
[0026] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0028] FIG. 1 illustrates the embodiment of the method forgetting the thermal images and optical images from a scene containing multiple subjects in operation, as described in the present disclosure
[0029] FIG. 2 illustrates an exemplary flow diagram of the proposed method for measuring the core body temperature of multiple subjects simultaneously, in accordance with an embodiment of the present disclosure
[0030] FIG. 3 illustrates an exemplary representation in the form of a block diagram of the embodiment used for measuring the core body temperature of multiple subjects, in the present disclosure
DETAILED DESCRIPTION
[0031] The following is a detailed description of embodiments of the disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0032] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations

specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0033] Various terms as used herein. To the extent a term used in a claim is not defined, it should be given the broadest definition possible in the pertinent art having given that term as reflected in printed publications and issued patents at the time of filing.
[0034] The embodiments described herein relate to a system for identifying the core body temperatures of multiple subjects in an area.
[0035] In one of the aspects, the present disclosure provides a method to measure one or more warm blooded subjects (humans and animals) using a combination of infrared images and optical images, and simultaneously processing them according to the rules in this disclosure to enable reliable, quick, non-invasive and remote core body temperature to be measured of the respective subjects in order for relevant decisions to be taken by the operator of the method which might in some way benefit the public society including but not limited to identification of potential influenza and/or disease, identifying fever, identifying hypothermia. Using this method a safe distance can be maintained with a potential carrier of infectious disease in accordance with protocols in order to limit the spread of the said disease. It can also be useful in other situations where a distance is needed to be maintained with the subject such as animals.
[0036] In the present disclosure, an embodiment of the physical implementation of the method would include a thermal sensor, an optical sensor, a signal processor and an enclosure. However, some embodiments of the invention might include more components while keeping the same general methodology. Some embodiments of the invention might also include different placements of the components while keeping the same general methodology.
[0037] FIG. 3 describes the technical setup where the embodiment of the method would be implemented. 301 is the device which is described in the present disclosure. 301 has the core components implementing the methods such as signal processing unit, power unit, other interfaces. 302 is the sensor array which contains both the thermal infrared sensor and the optical sensor to collect imagery data. 303 shows the field of view of the sensor array in which multiple subjects are present. It is of these subjects that respective core body temperatures have to be measured. In some embodiment a display device is also attached to the set up by means of an appropriate interface including but not limited to HDMI (High Definition Multimedia Interface), VGA (Video Graphics Array) or any other suitable interface. This display device would display the temperature of each subject in a suitable manner for the operator to read.
[0038] In some embodiments, the display device would also display visual alerts in a suitable format, if given the signal by the signal processing unit. Situations where alerts are displayed could be situations like if a higher than normal body temperature is found or if a lower than normal body temperature is found. Alerts can also be changed according to predetermined rules or if there is any violation of those rules.

[0039] FIG. 1 illustrates a flowchart of the methodology followed in the present invention in order to reliably, quickly, non-invasively and remotely measure core body temperatures of multiple subjects. The process begins with the image capture by the thermal infrared sensing unit shown in FIG 2 - 201. This sensor would typically include a thermopile that receives some infrared radiation and transforms that into an analog signal. 201 would also include an on-board analog to digital converter (ADC) that outputs a digital signal towards the signal processors input, via a suitable interface including but not limited to I2C, USB, SPI. In some embodiments, 201 would also include an on board signal processor that converts IR into a unique temperature reading per pixel. The first step of the process also has an optical sensor, 202, which collects the visible spectrum of light and outputs images which are then input to the signal processor, 203.
[0040] 203 is the signal processor that receives the input of thermal images from 201 and optical images from 202. The signal processor applies some machine learning techniques to extract the pixels corresponding to each subjects face if visible and in case the subject is human, described in step 105. This machine learning model is stored in memory module (206) and could include a plurality of model including but not limited to YOLO, Inception Model, and others in some embodiments. A software framework to run these models is also stored in memory module (206), including but not limited toTensorflow, Caffe, Keras, Pytorch, in some embodiments. Thereafter, the signal processor (203) extracts the corresponding set of pixels from the thermal image according to a predetermined look up table that establishes a one to one relationship between the pixels of the optical sensor and thermal sensor. This is described in step 104
[0041] The pixel values obtained by signal processor (203) from thermal sensor (201) contain the temperature values of each subject's facial skin temperature. Once these pixel values are obtained the signal processor (203) the temperature readings corresponding to the forehead are obtained by the signal processor (203). Subsequently the highest five temperature readings are taken by the signal processor (203) and their average is taken to produce one value, as described in 108. This value is the obtained skin surface temperature of the measured subject. In such a way one value for skin surface temperature is obtained for every subject visible in the field of view of the sensor array. This value is an accurate temperature measurement of the subjects skin temperature but certain embodiments might allow increases in accuracy by compensating for the minor heat loss that occurs due to the distance between the subject skin and the thermal sensor (201) itself.
[0042] If our subject is human and offset of 0.7° Celsius is added to the forehead skin temperature reading to get the core body temperature of the subject in accordance with the protocol established by the medical community. This is described in step 109. In some embodiments this core temperature reading can be displayed via a suitable display device to be viewed according to each subject in the field of view 303.
[0043] In certain other embodiments rules can be applied after the core body temperature is measured, in such a way that certain alerts can be generated in a suitable way if those rules are violated. One such rule which has utility in detecting human subjects with a high body temperature is that if the core body temperature of the human subject is above 38° Celsius an alert can be generated on the display device in a suitable manner. Since fever

might be a symptom of an infectious disease, early and rapid detection of such a system can help in preventing or controlling the spread of such a disease by not letting the subject come in contact with healthy individuals. Such a process as defined in the previous paragraphs can be run multiple times in the loop to the tune of more than 100x a second in order to rapidly, reliably, non-invasively, identify symptomatic individuals and to prevent spread of infectious disease.
[0044] methods consistent with the method described in figure 1 Main clued at least one but not all of the steps in that method. At least some of the steps mentioned in method in figure 1 may be performed by a processor circuit in a computer. Furthermore, the methods described in FIG 1 may include some steps performed in a different sequence or in parallel or simultaneously or almost simultaneously or overlapping in time.
[0045] To the extent that the term "include", "have", or the like is used in the description or the claims, search term is intended to be inclusive in a manner similar to the term "comprise" as "comprise" is interpreted when employed as a transitional word in a claim. While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
[0046] The present disclosure provides a quick, accurate, non-invasive, remote methodology for determining the core body temperature of multiple warm blooded subjects including but not limited to humans
[0047] The present disclosure provides an arrangement and embodiments to quickly, accurately, non-invasively, remotely determine the core body temperature of multiple warm blooded subjects including but not limited to humans
[0048] The present disclosure provides a system and a message to determine the core body of multiple humans and crowds in such a way that overcomes the drawbacks of systems that are presently in use and that can only measure core body temperature of single individual one at a time
[0049] The present disclosure provides a simple to use and cost-effective method for determining core body temperatures of large number of people that can be used as an early screening methods to prevent the spread of infectious disease
[0050] the present disclosure also provides a method to determine core body temperature of large number of subjects like livestock from a safe distance away.
[0051] the present disclosure also can be used as a method to determine any deviation from normal core body temperature of subjects which could be a symptom of a disease.

We Claim :
1) A quick, non-invasive and remote core body temperature measurement system for
multiple subjects comprising of the following components :
a. A thermal infrared sensor to receive the infrared radiation and generate
temperature measurement of all the pixels in the infrared image
b. An optical sensor to receive the visible spectrum of light and to recreate the
scene in an electronic image
c. A signal processing unit to fetch data from the thermal infrared sensor and
optical sensor and according to describe the rules compute the core body
temperature of the subject
d. A memory unit to store look up tables and to store the plurality of
temperature measurements as obtained by the signal processing unit
e. A display unit to show the temperature of the respective subjects
2) A core body temperature measurement system for multiple subjects as claimed in claim one which according to predetermined thresholds can raise alerts on the display unit or otherwise in case of any internal rule violation
3) A method to determine the core body temperature measurement of multiple subjects simultaneously, through the following steps :
a. Collecting infrared radiation data through a thermal sensor
b. Collecting visible spectrum data through an optical sensor
c. Using a signal processor to input IR data and optical data in order to compute
the core body temperature of multiple subjects
d. Providing a memory module to store the look up tables and to store the
temperature measurements of respective subjects
e. A display unit to display their respective temperature measurements of
multiple subjects
4) A method of claim 3 wherein the step of displaying each temperature measurement
of multiple subjects involves a comparison with predetermined thresholds to raise
alerts in case those thresholds are exceeded.