Infrared

Infrared light is a form of electromagnetic waves. Infrared can be visible light or can be in the form of microwaves. In its visible form, infrared can be seen as red or violet. Visible infrared waves are very short, measuring about 750 nm in length; longer infrared waves which are closest to microwaves are about 1mm in length, about the size of a microbial cell.

While shorter infrared waves can be seen as colors, as infrared waves get longer they give off radiation in the form of heat. Infrared waves are considered to be thermal. For instance, the sun gives off infrared wave lengths, your toaster gives off infrared wave lengths and even living organisms such as humans, dogs and cats give off thermal heat in the form of infrared wave lengths.

While most infrared wave lengths give off heat, you are probably aware of one of the most popular uses of infrared wave lengths- the TV remote control. Your remote control works via short infrared wave lengths, the visible kind and don't worry, these short wave lengths do not give off any heat.

Your TV remote is able to produce visible light waves, usually red that can be seen and distinguished by sensors in your TV set. Because infrared waves at the visible level are safe and easily seen and separated from other light waves, remote controls are very effective in controlling items.

Another effective use for infrared is the ability to see objects that give off infrared radiation. For instance, practically every object gives off thermal heat. Thermal heat is shown as infrared radiation. For instance, an oven gives off thermal heat, so does the skin of a human, and even an ice cream sundae has heat which can be seen via infrared radiation. As an object gets warmer, it gives off more infrared radiation. A toaster gives off far more radiation than an ice cube.

Because infrared radiation can be measured and seen with special equipment, there are now many ways to view objects either totally in the dark or at normal conditions. For instance, the military has developed special instruments in the form of night goggles that can easily see objects in pitch black dark. These goggles are able to see humans, vehicles and weapons. Each object usually gives off a special infrared radiation signature making it easy to spot which item is what. For instance, if you are looking to find a human on a hot beach, because each item has a different level of infrared radiation, so you can quickly find the human being.

Not only is infrared used in military systems, but also by NASA for exploring space and by weather satellites to accurately predict the weather in many regions. Infrared is an important tool for meteorologists to help plot severe storms and weather anomalies.