What is infrared light?
Also called infrared (IR), it is electromagnetic radiation that was discovered in 1800 by William Herschel, an astronomer.
Infrared light is not visible to us because its wavelength is longer than visible light and the human eye cannot view longer wavelengths. Lower wavelengths of infrared can be seen by humans. Infrared radiation is emitted because of energy states on the molecular level. Infrared that is found to emit from objects at room temperature are typically thermal radiation.
What does the word infrared mean?
“Infrared” means below red, referring to the frequencies that are lower than the red light that can be seen by the human eye.
What gives off infrared light?
The main source of infrared light is heat or thermal radiation, meaning anything that has a temperature emits infrared. The higher the temperature the more infrared radiation will be emitted.
Any object with a temperature higher than absolute zero (-459.67 degrees Fahrenheit /-273.15 degrees Celsius) emits infrared radiation. Therefore, even objects that we perceive as cold, like frozen foods, emit infrared.
A good example of infrared radiation is the heat we absorb from the sun. Nearly 50% of Earth’s external heat is sourced in the sun’s infrared radiation. Due to the sun’s high temperature over half of its light is visible to us, but objects at lower temperatures will emit most of their energy at infrared wavelengths without emitting visible energy.
IR radiation that you can feel even though it is invisible to the naked eye can be given off by certain heat sources such as furnaces, charcoal, electric heaters, and radiators.
An example of a powerful source of infrared light we can find on our planet is fire. Over 50% of the energy emitted by fire will be expressed in infrared.
You will find that infrared technology is becoming used in a wide range of different products that we have today.
But you may be surprised to learn that this form of technology was discovered in the early part of the 19th Century. But, it was quite some time before we fully understood its uses and were included into products that we use often today.
This technology is extremely powerful and is being used in a variety of different ways. You will find it being used not only in remote controls but also in autonomous vehicles.
Plus, infrared technology can now be put into existing systems that will provide them with new technical capabilities. As production of various devices increases, the costs will begin to fall and in turn make such technology more accessible for use in even more products in the future.
Forms of Infrared Light
This form of light lies between what are classified as the visible and microwave parts of the electromagnetic spectrum. It also has a range of wavelengths, just like the light we can see, and range from red to violet.
You have “near infrared” light which is the one on the electromagnetic spectrum that is closest to the light that we can see. Then there is “far infrared” and this is much closer to the microwave portion of the electromagnetic spectrum.
Far infrared light wavelengths are about the size of a pinhead, whereas near infrared light wavelengths are about the same size as cells in our body, so they are microscopic.
As far infrared wavelengths are thermal, we actually experience these on a daily basis in the form of heat, whether from the sun, a radiator, or a fire. As for near infrared light waves these don’t produce heat at all. It is these ones that you will find are used in remote controls for TV and other electronic devices.
Is infrared radiation dangerous?
Yes and no. Yes, infrared light can be dangerous at high levels of exposure for long periods of time. Infrared radiation can damage one’s cornea, lens, and skin. So, when working with infrared light for extensive amounts of time it is important to use protective gear.
No, it is not so dangerous during short exposure periods and can even be very beneficial. It is used in multiple healing therapies and is a fundamental part of our ecosystem.
What is infrared light used for?
Infrared has become popular supporting different night vision devices as they function most effectively in various conditions by emitting invisible light and therefore allowing the user to have visibility of his surroundings while staying undetected. These features have made infrared very popular with different military organizations, secret service, police forces, and even hunters.
Their thermal vision qualities are quite helpful in research when studying the body temperature patterns of humans and animals
Although this all may sound like advanced military technology, we encounter infrared technology on an almost daily basis. Many of our remote controls use IR waves working in pulses. A common example of this is a TV remote.
IR heating lamps are used to keep our food warm at many restaurants. They are efficient because they directly heat the food instead of the air around it. For that same reason IR saunas have become a common therapy, the special lamps can precisely raise the body’s core temperature. This is especially helpful to ease stress, sore muscles, detoxification, joint paint, weight loss, circulation, chronic fatigue, and generally improve one’s sleeping patterns.
It can also be used to treat certain injuries by optimizing the IR wavelength and directing it at the site of the injury.
IR is also used for deep space telescope technology because it can pass through dense gas and dust more efficiently.
Optical fibers use IR LEDs to communicate.
Infrared sensors are used on satellites to study weather patterns and detect Earth’s radiation in order to forecast our planet’s weather.
IR motion sensors are effective for both daytime and nighttime. Making them very useful in different security systems and or scientific research.
Advantages & Disadvantages of Infrared
There are many ways in which Infrared can now be used to make our lives a lot easier as we’ve shown above.
It is vital when you are thinking of using any kind of infrared device that you know what the advantages and disadvantages are of using such devices.
Advantages of Infrared
- It will provide you with a secure line of communication
- Batteries in these devices last for a long period as they use very little power
- The response time of these devices is quick
- Offers good stability over time
- You will find neither oxidation or corrosion will affect the infrared sensors accuracy
- It is able to deliver Hai repeatedly
Disadvantages of Infrared
- You will notice that infrared frequencies can be affected by hard objects, as it is unable to pass through them
- High power infrared if looked at can cause damage to eyes
- You will find that when used in monitor and control applications you are only able to control one device at a time
- In order for the transmitter to communicate with a receiver it requires to have direct line of sight to it
- It has a much lower rate of data transmission compared to that of a wire transmission
Why is infrared important?
IR plays a critical role in the Earth’s climate because the Earth must radiate infrared light equivalent to the sunlight absorbed in order to maintain its temperature.
How does an infrared flashlight work?
Infrared light cannot be seen by the naked human eye. Therefore, infrared flashlights are paired with night vision devices, allowing the user to see in the dark undetected. The goggles and flashlight must be at similar frequencies to be able to work together.
The main difference between an LED light and an IR light is the spectrums they emit.
Infrared technology is a very important subject today and worth learning about, especially how it can affect your health.
Here is how to make your own Infrared light at home:
Step 1 You will need to purchase the following items:
- Flashlight (the simpler it is, the easier it will be to take apart later)
- Infrared LED lights (We recommend 8mm LEDs, but it really depends on the size of your flashlight, and the number of LEDs you want to fit inside)
- Soldering iron
- Batteries that fit your flashlight of choice
Step 2 Disassemble the flashlight completely. Discarding the bulb. Keep only the body, lens, connecter, and reflector.
Step 3 Solder your LEDs together in a square (we recommend using four LEDs to keep the wiring simple). Make sure to keep the positive leads in the center and the negative leads on the outside. Leave two extra leads for wiring. You want to match your wire length to fit the positive and negative ports in your connecter.
Step 4 Separate the lamp from the housing and reassemble with infrared LEDs.
Step 5 Solder through the lamp housing to the connecter using the two extra leads previously mentioned.
Step 6 Reassemble flashlight with the fitting batteries.
Alternatively, you can do something similar with an LED circuit board, a small plastic box, a battery connecter, and batteries.
Infrared and animals
Although the human eye is not designed to perceive IR light, there are many animals that genetically have infrared vision in order to survive. These animals include snakes, blood-sucking insects, as well as certain groups of fish and frogs.