Infrared thermography technology is a science devoted to the acquirement and analysis of thermal informative materials from non-contact measurement equipment. The invention relies on the infrared radiation (IR) (below red), a type of electromagnetic radiation with an extensive wavelength than those of observable light (Usamentiaga, Rubén et al 12306). Notably, any item at a temperature greater than absolute zero produces infrared radiation, hence, cannot be seen by the human eye. The infrared measuring object receives the infrared radiations released by the device and changes it into an electronic signal.
The variance between a visible and infrared image is that the visible picture is a depiction of the reflected light on the object. Consequently, in the infrared image, the instrument is the source and can be detected by an infrared camera without light (Usamentiaga, Rubén et al 12306). Pictures attained through the integration of infrared camera are changed into visible images by allocating a color to each electromagnetic energy level. As such, thermal cameras are passive sensors that obtain the infrared radiation discharged by apparatuses with a temperature higher than absolute zero (Gade & Moeslund 1). Therefore, this paper discusses the infrared light (infrared camera), its historical evolution, and current applications.
History and Evolution of Infrared Camera
The evolution of the infrared camera dates back to 1947 when the first infrared scanner was discovered taking one hour to establish a distinct thermogram (Szajewska, 1068). However, the initial effort of sensing the globe in the infrared spectrum was done in the nineteenth century. Consequently, numerous concepts of IR presentations can be traced to the start of the twentieth century in which Barker obtained a patent for identifying icebergs in 1914. Barker anticipated utilizing the IR sensors for managing and monitoring forest fires in 1934, whereas Nichols proposed analyzing hot-rolled metal through IR in 1935 (Vavilov 1). Considerably, the contemporary exploration of material thermal characteristics goes back to the activities of Vernotte which initiated the notion of single-sided material thermo physical object dimension. Additionally, Vernotte devised the idea of effusity that is now presently employed in the thermal non-destructive testing (TNDT). Importantly, the chief single-sided, non-contact thermal description by pulse infrared radiometric capacity was accomplished in 1959 by Hardy (Vavilov 1). The architect determined the effusity of the living skin on the forehead of the sick.
In the period of 1960s, the use of IR thermography started explicitly in the assessment of electrical installations, radio electronic mechanisms, and buildings (Vavilov 2). Since 1960, the scrutiny of aerospace objects has been one of the most critical integrations of active TNDT. At the end of the 1970s, the usage of IR thermography driven by successful expansions of IR inventions in the military was qualitative, thereby deterring progressive rivalry of TNDT with various inspection instruments (Vavilov 2). However, the first infrared-sensitive automated television camera was created in 1929 by the Hungarian physicist Kalman Tihanyi. Similarly, the early infrared line scan innovation was the British yellow duckling of the mid-1950s. The device used a constant rotating mirror and detector with a Y-axis scanning through the movement of the carrier plane.
Consequently, the adoption of the technique by the military steered the prompt advancement of the infrared technology. As such, digital cameras have become enormously popular because of their significant resolution and mechanization capability in the digital photogrammetric documentation (Yastikli and Esra 712). Currently, the infrared thermography is an established system and is being used in several fields of study. The recognition of the novelty has promoted the creation of infrared gadgets that are distinct in weight, measurements, nature, and performance (Meola 1). Conversely, comprehensive exploration of the infrared thermography needs an understanding of the basic models and presentation of standard processes.
Principles Implied in the Infrared Camera
The extent of radiation produced by an item increase with temperature, hence, thermography enables an individual to observe differences in temperature. As such, a thermal imaging camera is able to determine the algorithms by analyzing the data, thus, creating a picture (Battalwar, Janhvi and Utkarsha 2). The camera integrates numerous sources of information based on the regions revolving around the device to calculate the value rather than determining the definite temperature. Notably, portraits from the infrared cameras normally have a single color network since the instrument integrates a sensor that does not differentiate various wavelengths of IR. The color camera entails an intricate structure that helps in distinguishing wavelengths and color generally has minimal importance outside the ordinary visible range (Battalwar, Janhvi and Utkarsha 2). Considerably, an extraordinary camera can notice the infrared radiation in a manner that resembles what a standard camera does to the visible rays.
Pros and Cons of Infrared Camera
However, with the proliferation of the infrared cameras in various fields, numerous challenges and benefits of its use have been documented. The major setback is that the item colors and visibility relies on the producer of the energy like the sun or artificial lighting (Gade & Moeslund 1). As such, the picture depends on the radiance with a modifying strength, color balance, and directions. Moreover, the infrared imaging can capture inaccurate materials taken by the apparatus when the temperatures are close, thereby making the object indistinguishable. Consequently, the thermo-imaging paraphernalia’s are expensive, hence, can only be used by large syndicates and public services (Battalwar, Janhvi and Utkarsha 5). Further, the images are normally difficult to interpret even with expertise.
Nevertheless, the technique has some advantages such as allowing the user to take fast moving objects and also determine the transforming configurations of targets (Battalwar, Janhvi and Utkarsha 5). Additionally, thermography enables measurements of places that are inaccessible or risky for other systems. Temperatures can easily be determined for an object that is hazardous to reach, hence, the outcomes are critical to interpreting as they are got in an image layout. Consequently, thermography incorporates a thermo-imaging technique that assists one in seeing through the smoke, thus, can be used in firefighting (Battalwar, Janhvi and Utkarsha 5).
Applications of the Infrared Camera
The infrared cameras can be developed either as scanning apparatus, taking only one point of a portrait at a time or through a staring spectrum, as a two-dimensional infrared focal plane array (Gade & Moeslund 6). Notably, the two forms of detectors integrated into the infrared cameras include the photon and thermal sensors. As a result, the capability to observe the temperatures in a scene can be of substantial benefit in numerous applications. The temperatures can be significant to understand specific targets or give informative materials about the item.
The technique has been used in the inanimate objects, humans, and agriculture (Gade & Moeslund 6). The infrared camera is used in the identification of fungal infections in stored food materials as it can distinguish between healthy and contaminated feeds. Moreover, passive thermography imaging is mostly applied in the food production and in monitoring heat systems. Inanimate targets uphold a continuous temperature that relies on the neighboring temperature and the level of added energy which produces heat. Therefore, infrared cameras can be integrated to examine both the temperature and the object (Gade & Moeslund 6). Consequently, the cameras have been useful in the determination of the amount of heat lost in a building and special hand-held imaging instruments have been created based on the infrared application. Similarly, the concept is used as diagnostic equipment for electrical joints in power conduction process. Additionally, the thermal cameras are very important for the surveillance and recognition of invaders since they have the ability to function at night.
The invention of infrared cameras relies on the infrared radiation (IR) (below red) which is a type of electromagnetic radiation with an extensive wavelength than those of observable light. The infrared measuring object receives the IR released by the device and changes it into an electronic signal. Therefore, pictures attained through the integration of infrared camera are changed into visible images by allocating a color to each electromagnetic energy level. As such, thermal cameras are passive sensors that obtain the infrared radiation discharged by apparatuses with a temperature higher than absolute zero. In the period of 1960s, the use of IR thermography started explicitly in the assessment of electrical installations, radio electronic mechanisms, and buildings. Currently, the infrared thermography is an established system and is being used in several fields of study. The infrared camera is used in the identification of fungal infections in stored food materials as it can distinguish between healthy and contaminated feeds. Consequently, the cameras have been useful in the determination of the amount of heat lost in a building.
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