First discovered in 1800 by William Herschel, infrared “light” is a type of electromagnetic radiation on the electromagnetic spectrum. It is invisible to the human eye, and it is mostly produced by heat. That’s why infrared technology has long been used in technologies like thermal imaging tools or in telescopes used by astronomers to study the universe.
But other technologies use infrared light as a way to send information between different locations, like with a T.V. remote. It’s a relatively low-energy and secure way of transmitting information, but the biggest drawback is its range and susceptibility to interference; because infrared can’t pass through solid objects, it’s essentially limited in usefulness to transmitting data within a given room. Even a simple ray of sunlight can be enough to block the infrared beam from getting to its destination. Though it has a high degree of accuracy in a given space, it can be expensive to outfit an entire building with the sensors needed to collect accurate information, particularly retrofitting old buildings. As a result, infrared is not generally considered a good choice to use for indoor positioning technologies. Effective positioning tools require data about a much larger terrain than just a single room.
Infrared is a type of electromagnetic radiation that is not visible to the naked eye. And, ironically, it is often referred to as infrared light. Infrared is a common type of radiation given off by heat; when you feel something hot, you are feeling infrared radiation. Infrared radiation was first discovered by British scientist William Herschel in the 1800s. During an experiment to test the temperatures of different colors, Herschel found that red was much warmer than blue, highlighting that infrared is given off by heat. Infrared has a long wavelength and is just beyond the realm of visible light in the electromagnetic spectrum.
Since its discovery, scientists have found that infrared radiation has many innovative uses, which has led to the development of infrared technology for commercial and military aircraft, thermal imaging cameras, home entertainment systems, and much more.
Infrared technology uses also include tracking and indoor positioning services (IPS). But how exactly does infrared technology work and is it effective for large-scale IPS?
How Does Infrared Technology Work and What Is it Used for?
So first, what is infrared technology and how does it work? Broadly speaking, there are two types of infrared technology: those that detect infrared radiation and those that send information via infrared radiation (called wireless infrared technology).
Infrared technology that detects infrared often involves sensors that turn detected infrared radiation into usable information.
Let’s take one of the most common examples of infrared technology: thermal imaging. Because infrared is the radiation given off by heat, detecting infrared radiation can provide information about different heat sources. Thermal imaging cameras use sensors that take information about different temperatures (e.g., different levels of infrared radiation) and turn that information into images that the naked eye wouldn’t have been able to detect.
Thermal imaging cameras have uses that run the gamut of industries and purposes, both in military and civilian areas. Astronomers, for example, have developed tools that detect infrared radiation in space because infrared can pass through thick areas of dust and cloud that visible light cannot, allowing them to learn about unseen aspects of the universe.
What is Wireless Infrared Technology?
Instead of detecting infrared radiation, wireless infrared technologies use infrared radiation to transmit and convey data and commands.
Probably one of the most common examples of wireless infrared technology is a T.V. remote. Sensors in a remote transmit an infrared laser to a sensor in a T.V., which communicates a particular command to the T.V. (turn on, volume up, etc.).
There are generally two types of wireless infrared technologies: directed and diffuse. Directed technologies use infrared lasers to transmit information, but there must be an unobstructed line of sight between the source of the infrared light and the receiver. Some technologies use this to their advantage—for example, certain security systems rely on the disruption of a beam of infrared light to detect if someone has crossed a particular threshold.
Diffuse infrared technology scatters the beam, making it a bit harder to block. T.V. remotes are an example of diffuse infrared wireless technology: as long as you’re in the same room, it should work.
How is Infrared Technology Used in IPS?
In IPS, infrared technology is commonly used to gauge where someone or something is in a particular room. Sensors to send and receive signals are installed in a room and can continually relay positioning information.
While there are some benefits to using infrared, there are also several limitations ultimately making infrared a less common choice in IPS.
What Are the Benefits of Infrared Technology for IPS?
Infrared has a few benefits that could be considered when choosing an IPS system. Here are three key benefits of using infrared to send information:
- Infrared technology has the benefit of longevity—it’s been around for a while, it is widely used, and well respected. Put another way, it’s a well-understood and fairly reliable technology.
- Infrared requires low amounts of energy to power, making it relatively inexpensive (think about how your remote only needs batteries).
- Infrared is a relatively secure way to transmit information. It’s very hard to “eavesdrop” on information being transmitted via infrared.
What Are the Limitations of Infrared Technology for IPS?
Despite some benefits, there are a lot of limitations with infrared uses in IPS, particularly with wireless technology. The biggest issue with infrared technology is its range of use. You may have noticed this with your T.V. If you are too far away, the remote won’t work. That’s because infrared beams cannot pass through solid objects, which significantly limits the distance they can travel, and therefore the range of the information they can convey.
As a result, wireless infrared technologies are essentially limited to room-based communications. While it could be possible to communicate infrared information between homes if they have windows that face each other, for example, buildings may not always be set up like that. And while infrared can be very accurate about what it detects in a given space, every room in a building would still need to be installed with sensors to help detect the infrared lasers. This can require retrofitting old buildings, which is expensive.
These limitations are exactly what make infrared a less popular choice for IPS.
Infrared technology has been around for some time and has a lot of uses, from the detection of infrared radiation to the use of infrared to send and receive information, commands, etc. But when it comes to navigating around a large, complex building, the limitations of infrared technology become apparent very quickly. If infrared can’t pass outside of a room, it doesn’t offer much for mapping and transmitting information about large buildings or a person’s location inside them.
Mapsted offers a more robust, unique approach to indoor positioning technology that combines a range of data sources to provide the most accurate, up-to-date information on someone’s location inside a particular building.
Frequently Asked Questions
Q1. What is Infrared?
Ans. Infrared refers to light just outside the spectrum of visible light. It is a type of radiation often produced by heat and was first discovered in 1800.
Q2. What is infrared technology?
Ans. Infrared technology is a technology that either detects infrared for specific purposes or that uses infrared to send information. Infrared technologies have been around for a long time.
Q3. What are some common examples of infrared technology?
Ans. Infrared technology examples include thermal imaging, which is designed to detect infrared radiation, and T.V. remotes which is an example of wireless infrared technology that uses infrared radiation to send and receive information.
Q4. How is infrared technology used in indoor positioning systems?
Ans. It is commonly used to provide accurate information about someone’s location in a specific room.
Q5. Is infrared technology effective for indoor positioning systems?
Ans. The general answer is no. A beam of infrared light can be very easily disrupted (e.g., by a solid object, by the sun) meaning that any information being sent via that light won’t reach its target. As a result, wireless infrared technology is often limited to a single room, significantly limiting its usefulness.