What is Thermal imaging?

What is Thermal imaging

It is a method of improving visibility of objects in the dark or near-absolute darkness by detecting the objects' infrared radiation, thus creating an image based on that information. Generally, thermal imaging, near-infrared illumination, low-light imaging are the three night vision technologies used. However, thermal imaging works in environments without any ambient light and can penetrate smoke, fog and haze.

Thermal Imaging Devices

Most thermal-imaging devices scan at a rate of 30 times per second. They can sense temperatures ranging from -4 degrees Fahrenheit (-20 degrees Celsius) to 3,600 F (2,000 C), and can normally detect changes in temperature of about 0.4 F (0.2 C).

Two common types of thermal-imaging devices:

Un-cooled - This is the most common type of thermal-imaging device. The infrared-detector elements are contained in a unit that operates at room temperature. This type of system is completely quiet, activates immediately and has the battery built right in.

Cryogenically cooled - More expensive and more susceptible to damage from rugged use, these systems have the elements sealed inside a container that cools them to below 32 F (zero C). The advantage of such a system is the incredible resolution and sensitivity that result from cooling the elements. Cryogenically-cooled systems can "see" a difference as small as 0.2 F (0.1 C) from more than 1,000 ft (300 m) away, which is enough to tell if a person is holding a gun at that distance.

Functions and applications of thermal imaging – a night vision technology

The military uses night vision to locate enemy targets at night, as well as for navigation, surveillance and targeting. Thermal-imaging and image-enhancement technologies are used by the police and security for surveillance. Hunters and nature enthusiasts use NVDs to maneuver through the woods at night.

Applications:

• Military
• Law enforcement
• Hunting
• Wildlife observation
• Surveillance
• Security
• Navigation
• Hidden-object detection
• Entertainment