| hermographic camera or what is called FLIR, Forward | | | | ambient environment. These detectors are very |
| Looking Infrared, is type of cameras which produces | | | | important because they cool the sensors and prevent |
| an image with the use of infrared radiations or | | | | them from burning. Each captured photo must be |
| wavelength that differs from the common cameras | | | | taken a few minutes later so the camera can work |
| which use the visible light. | | | | again properly. Cooling is both power-hungry and |
| How do thermal cameras work? Since it depends on | | | | time-consuming, besides, it’s too expensive. |
| the wavelength, it’s necessary to know a bit | | | | How does the cooling system work inside this kind of |
| about the radiations produced by objects. Each object | | | | camera? First, there are two cooling systems; one of |
| produces a certain amount of black bodies. From its | | | | them is too expensive, but provides higher qualities, and |
| name we can guess that it absorbs the | | | | the other is more proper to certain fields. |
| electromagnetic radiation falling on it. | | | | Regarding to the main system, rotary Stirling engine |
| It is black because it cannot reflect or even transmit | | | | cryocoolers, though it is costly but it provides higher |
| these radiations, which make the object black when it | | | | image qualities than the un-cooled infrared detectors. |
| becomes cold. So, it is the camera’s job to | | | | The other cooling system is to use nitrogen gas bottled |
| detect these radiations, since, the more temperature | | | | at high pressure. The pressurized gas is expanded |
| the object is, the more production of infrared radiation | | | | through small hole and then passed over a micro-sized |
| of black bodies. It is the same process done by a | | | | heat exchanger leading to renew cooling through |
| usual camera that handles visible light. | | | | Joule—Thomson effect. Joule—Thomson |
| Images from infrared cameras prefer to use sensor, | | | | effect describes the change of temperature of a gas |
| which does not distinguish the various wavelengths of | | | | when it is forced through valve while in isolation so |
| infrared radiations. It is capable of working in a | | | | there is no change of heat with the surrounding area. |
| complete darkness regardless the surrounding light, that | | | | On the other hand uncooled infrared detectors use a |
| is, light does not affect thermal cameras. However,, a | | | | sensor which makes the imaging process at the |
| color camera needs more complex system to | | | | surrounding temperature or closer to the ambient |
| differentiate between the different wavelengths. | | | | temperature by using temperature control elements. It |
| It is the role of the thermal camera to detect the | | | | is cheaper to produce lower qualities than its |
| radiations. Thus, knowing more about the types of | | | | counterpart. |
| these detectors can be beneficial for their users. | | | | After all, what are the benefit and the applications of |
| They are of two types: Cooled infrared detectors and | | | | such cameras? This product is very substantial in |
| Uncooled infrared detectors. | | | | various fields. Firefighters, for example, can use it for |
| Cooled infrared detectors are usually contained in a | | | | rescuing people to see through smoke and to locate |
| thermos, which separates the components from the | | | | people’s position in the firing place. |