All objects release infrared energy (heat) according to their temperature. The infrared energy emitted by an object is called its thermal signal. Usually, the hotter an object is, the more radiation it emits. Thermal imager (also known as thermal imager) is essentially a thermal sensor, which can detect small temperature differences. The device collects infrared radiation from objects in the scene and creates electronic images based on information about temperature differences. Since objects are rarely at exactly the same temperature as other objects around them, they can be detected by the thermal imager, and they will look obvious in the thermal image.
Thermal images are usually gray in nature: black objects are cold, white objects are hot, and the depth of gray indicates the difference between the two. However, some thermal imagers add color to the image to help users identify objects at different temperatures.
What is thermal imaging?
Infrared thermal imager can effectively convert heat (i.e. heat energy) into visible light, so as to analyze the surrounding environment. This makes them very versatile. Biological and mechanical devices emit heat and can be seen even in the dark. These thermal images are very accurate and work effectively with only a small amount of heat.
How does thermal imaging work?
Visible light is extremely useful to humans and other organisms, but it is only a small part of the electromagnetic spectrum. Infrared radiation generated by heat occupies more “space” in the spectrum. The infrared thermal imager captures and evaluates the interaction of absorbed, reflected and sometimes transmitted heat.
The level of thermal radiation emitted by an object is called its thermal signal. The hotter a given object is, the more it will radiate into the environment. The thermal imager can distinguish between heat source and small thermal radiation difference. It compiles these data into a complete “heat map” to distinguish by heat level.
What’s the use of thermal imaging?
Originally used for night reconnaissance and combat. Since then, they have been improved for use by firefighters, electricians, law enforcement personnel and rescue teams in disaster areas. They are also widely used in building inspection, maintenance and optimization.
How to realize thermal imaging?
Thermal imaging can be a compact and effective technology. The simplest thermal imager can evaluate the heat source centered on the crosshair. More complex systems provide multiple comparison points, so users can analyze environmental conditions. The thermal image palette varies greatly, from a monochrome palette to a complete “pseudo color” palette.
What should you look for in thermal imaging equipment?
Specifically, your need for a thermal imager depends on the environment you use. However, two areas are the key quality distinguishing factors of thermal imagers: detector resolution and thermal sensitivity.
Like many other resolutions, resolution describes the total number of pixels – for example, a resolution of 160×120 consists of 19200 pixels. Each individual pixel has its associated thermal data, so a larger resolution can produce a clearer image.
Thermal sensitivity is the difference threshold that can be detected by the imager. For example, if the sensitivity of the device is 0.01 °, objects with a temperature difference of one percent can be distinguished. The minimum and maximum temperature ranges are also important.
Thermal imagers have some basic limitations: for example, they cannot pass through glass due to the reflective properties of materials. They can still see but can’t penetrate the wall. Nevertheless, thermal imaging has proven useful in many applications.
Post time: Dec-07-2021