Large-Scale Infrared Camera Temperature Measurement and Screening

Large-Scale Infrared Camera Temperature Measurement and Screening

   Previously, the effectiveness of thermal screening by large-scale infrared thermal imaging cameras was studied, and infrared thermal images of the neck and face were recorded. It is observed from the research that the infrared thermal imaging method is more sensitive to distinguishing fever patients, similar to the results of self-reported fever cases, and the corresponding conclusion is drawn: infrared thermal imaging camera is an effective tool for rapid and non-contact large-scale fever screening. At the same time, the normal ear temperature of different age groups was measured with infrared thermal imaging cameras. The outbreak of severe acute respiratory syndrome (Severe Acute Respiratory Syndrome, SARS) and bird flu has paved the way for effective large-scale fever screening with infrared thermal imaging cameras. In 2003, thermal imaging cameras were successfully used for large-scale screening of fever in SARS patients. Screening potentially infected persons is the first step to prevent the large-scale spread of SARS. The statistical results of using infrared thermal imaging cameras to monitor the body temperature of entry and exit ports are also proposed, and methods to improve the fever alarm rate and detection rate are discussed. Infrared thermal imaging cameras are indeed effective in large-scale fever screening, suggesting that elevated body temperature is one of the most common syndromes of many infectious diseases, including SARS. Therefore, thermal imaging cameras are a powerful tool for preliminary large-scale screening of subjects during a public health crisis. During the 2009 influenza outbreak, passengers at Narita International Airport in Japan used thermal imaging cameras when entering security checks. It is reported that when the epidemic fever is spread on a large scale, the highest risk population is children, and a research on the detection of children's fever based on infrared thermal imaging cameras is carried out. It is proposed that thermal imaging cameras can be considered as a potential screening tool for fever temperature measurement, and it is found that the axillary temperature (measured with a conventional thermometer) and the temperature of the inner corner of the eye (measured with an infrared thermal imager) are highly correlated. The distribution of body surface temperature of children with fever was discussed, and the distribution map of human body surface temperature was drawn. With the emergence of modern infrared thermal imaging cameras, data acquisition and processing technologies, real-time high-resolution infrared thermal imaging images are gradually taking shape, which may promote further research in fever screening.

Figure 1. Infrared thermal imaging camera temperature measurement screening

   Today, we rely on infrared thermal imaging technology to provide non-invasive, non-contact, and quantifiable thermal imaging of the skin. This information is of considerable value for evaluating the physiological mechanisms and pathologies that can be observed in the peripheral circulation of the skin surface. The key to infrared thermal imaging camera temperature measurement and screening is that the thermal imaging camera, the operator, and the screening site comply with common standards to ensure reliable, consistent and comparable data. The three most important factors affecting the accuracy of the data are the status of the subject, the infrared equipment and the screening environment. In addition, the public health crisis and huge economic losses caused by epidemic outbreaks have highlighted the importance and necessity of infrared thermal imaging screening methods. The most urgent task is to achieve standardization of screening equipment, screening procedures and screening environment as soon as possible.

   The standardization of medical infrared camera temperature measurement and screening in my country can start from the following aspects.

   (1) Accurately define the performance of the infrared thermal imaging camera, especially the indicators related to or affecting temperature measurement must be accurately described, so that different instruments designed for the same purpose can be compared. This goal can only be achieved with the full cooperation of manufacturers and marketing agencies.

   (2) Provide for the use of consistent screening environmental conditions. Use approximate environmental conditions to minimize the influence of factors such as temperature, humidity, airflow, and stray light on the screening results, and increase the reproducibility of the screening results. At present, a cabin-type thermal imaging camera (equipped with a closed examination room) has appeared on the market, which provides a controlled screening environment for screening objects.

   (3) Screening part refers to a body part that needs to be determined when the human body obtains a meaningful temperature measurement. This part can provide reliable data on a large section of the population. It is important to understand that skin temperature not only depends on the core temperature of the body, but may also be affected by other physiological and environmental factors. Studies have shown that the central area adjacent to the inner corner of the eye is a reliable measurement point.

   (4) Establish a reference database of infrared images on the surface of human skin, and use computer-aided diagnosis to detect and identify human fever-related diseases.