What we’ve learned from largest methane gas leak in the U.S. Invisible disaster: Infrared images from the Environmental Defense Fund show a huge plume spewing from the ground. Two years ago today, the largest U.S. methane leak was discovered. The leak in northwest Los Angeles County focused attention on the state’s aging gas wells. Disaster
Methane is the major component of natural gas, which heats our homes and recently surpassed coal as the top fuel for generating electricity in the United States. But methane is also a powerful greenhouse gas that contributes to global warming. And because methane is highly flammable, gas leaks pose a significant safety hazard, as we
Thermal imaging or infrared camera images are often used in news coverage for good reason: thermal vision is pretty damn impressive.
The technology doesn’t quite allow you to “see through” walls, but it’s about as close as you can get to x-ray vision.
But once the novelty of the idea has worn off, you might be left wondering: what else can I actually do with a thermal camera?
As it turns out – quite a lot. In fact, we’ve just come up with over 60 different uses.
Feel free to add any extra ideas in the comments section below, or contact us if you’d like some advice on which thermal imaging camera is right for you.
1. Surveillance – see hiding burglars or track someone fleeing a crime scene.
Infrared camera vision from a Massachusetts State Police helicopter helped to find traces of the Boston Marathon bombing suspect’s heat signature as he lay in a tarp-covered boat.
2. Firefighting – quickly identify if a spot fire or camp fire is actually out, or just about to reignite.
3. Search & rescue – find out where people are in darkened or smoke-filled rooms.
The infrared spectrum is divided into near-IR, shortwave (SWIR), medium wave (MWIR) and long wave (LWIR). To detect radiation at these wavelengths, a number of different detector technologies are used. While shortwave IR sensors are typically composed of Indium Gallium Arsenide (InGaAs), MWIR sensors typically rely on Indium Antimonide (InSb). SWIR and MWIR detectors can be actively cooled, increasing sensitivity and at the same time adds to the cost of cameras based around them.
A new drone platform designed for public safety and military applications offers the unprecedented capability of being able to react nearly instantaneously to the movement of a person or object.
In the LWIR range, Mercury Cadmium Telluride (MCT) and Strained Layer Superlattice (SLS) detectors provide a high-level of temperature precision. However, both technologies require active cooling, which increases cost. A lower cost, albeit less sensitive option in the LWIR, is the microbolometer, typically found in less expensive handheld cameras. For many applications, microbolometer-based cameras provide an affordable alternative to those that are actively-cooled. The wavelength ranges of all these detectors is illustrated in Figure 1.
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| Figure 1: Disparate detector technologies are used to image the infrared spectrum. These range from InGaAs detectors for SWIR to MCT for LWIR applications. |
A thermographic camera (also called an infrared camera or thermal imaging camera) is a device that forms an image using infrared radiation, similar to a common camera that forms an image using visible light. Instead of the 400–700 nanometre range of the visible light camera, infrared cameras operate in wavelengths as long as 14,000 nm (14 µm). Their use is called thermography.
Infrared was discovered in 1800 by Sir William Herschel as a form of radiation beyond red light. These “infrared rays” (infra is the Latin prefix for “below”) were used mainly for thermal measurement.[1] There are four basic laws of IR radiation: Kirchhoff’s law of thermal radiation, Stefan-Boltzmann law, Planck’s law, and Wien’s displacement law. The development of detectors was mainly focused on the use of thermometer and bolometers until World War I. A significant step in the development of detectors occurred in 1829, when Leopoldo Nobili, using the Seebeck effect, created the first known thermocouple, fabricating an improved thermometer, a crude thermopile. He described this instrument to Macedonio Melloni. Initially they jointly developed a greatly improved instrument. Subsequently Melloni worked alone, developing an instrument in 1833 (a multielement thermopile) that could detect a person 10 meters away[2]. The next significant step in improving detectors was the bolometer, invented in 1880 by Samuel Pierpont Langley.[3] Langley and his assistant Charles Greeley Abbot continued to make improvements in this instrument. By 1901, it had the capability to detect radiation from a cow from 400 meters away, and was sensitive to differences in temperature of one hundred thousandth of a degree Celsius.[4]
The first advanced application of IR technology in the civil section may have been a device to detect the presence of icebergs and steamships using a mirror and thermopile, patented in 1913.[5] This was soon outdone by the first true IR iceberg detector, which did not use thermopiles, patented in 1914 by R.D. Parker.[6] This was followed up by G.A. Barker’s proposal to use the IR system to detect forest fires in 1934.[7] The technique was not truly industrialized until it was used in the analysis of heating uniformity in hot steel strips in 1935.[8]