Thermal Imaging Camera

The image that thermal imaging camera (TIC) produce depicts the object’s temperature. Typically, the image’s brightest (warmest) areas are coloured white, its middle-temperature regions are reddest (or yellow-orange hue), and its lowest (coolest) areas are coloured black (or blue-purple hue). As a result, a thermal picture offers an in-depth temperature map of the region being studied, identifying hotspots and other anomalies that could require additional research.

Unlike visible light cameras, which are susceptible to wavelengths between 400 and 700 nm, infrared cameras can detect wavelengths between roughly 1,000 and 14,000 nm.

Infrared (IR) radiation can be felt as heat, yet it is undetectable to the naked eye. The item appears dull red as its temperature rises to roughly 500 °C. The emission spectrum becomes stronger and reaches into the range of human vision. It emits an increasing amount of orange, yellow, green, and blue light as its temperature rises further (and eventually become ultraviolet). The IR radiation is known as thermal radiation because it shows how a body’s internal energy is transformed into electromagnetic energy.

Certain materials, like the polythene bag, are transparent in the infrared but dense to visible light. Further, certain materials, like the man’s spectacles, are transparent to visible light yet dense in the infrared. Visible light (in-between section of the electromagnetic spectrum) is a radiation that is visible to the human eye. We are unable to see infrared radiation because our eyes are not sensitive to wavelengths that are outside of the visible spectrum’s red end.

Thermal cameras are capable of detecting the heat signatures of objects in complete darkness and producing an image by utilising the variations in temperature.

For thermal imaging, conventional optical lenses—which are usually built of glass—are unsuitable because of their opacity to infrared wavelengths. Thermal imaging lenses are made of specific substances such as Germanium, crystalline silicon, calcium fluoride, and some types of chalcogenide glasses.

The temperature, that an object is functioning at, can be approximately presented by thermal photographs, also known as thermograms. It is challenging to determine an object’s temperature precisely with thermal imaging since infrared energy comes from a variety of sources.

A thermal imaging camera directs infrared light onto a unique detector chip, or to a sensor arrangement made up of thousands of grid-arranged detection pixels. Every pixel generates an electrical signal in response to infrared radiation that strikes it. Next, a set of mathematical algorithms would be used by the TIC to make a colour map of the object’s apparent temperature.