Basic Information On Near-infrared Spectroscopy And Its Uses

By Author: George Melcher
Total Articles: 9
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Are you familiar with fingerprint identification? Your palm and fingers are covered with distinct ridge patterns that are unique to you. No one else in the world has the same ridge patterns on their fingers or palm, which makes it easy to identify you using your finger and palm prints. But elements don’t have fingerprints.

They do, however, have something better: emitted light. When light is shined at a particular object, it absorbs the light and refracts it back. The light emitted by different objects are unique to them, and by analyzing the different wavelengths of this light, you can identify the object—much like fingerprint scanning. NIR spectrometers, the machines used to read light, compare results to known light patterns to identify the object they’re examining.

The use of light in science started when Euclid first started playing with mirrors back in 300 BC. Sir Isaac Newton was the one who came up with the term ‘spectrum’ as a name for the range of colors produced by running light through a prism. The first spectrometers were very primitive, but the technology has since evolved until they gave ...
... birth to the spectrometers scientists use today.

Spectrometers are fairly straightforward. All you have to do is warm it up for a bit, stick the object you want identified into the machine, and wait for the results to come out. You can also choose not to put anything into the machine and just let light pass through—spectrometers can analyze that too. Scientists sometimes do this when they want to analyze light from deep space.

But what exactly goes on in the machine? Well, a NIR spectrometer needs the object to be in a gaseous state to examine it. That’s why you need to warm the machine up a bit before using it. The temperature inside the spectrometer vaporizes a part of the sample which then refracts the NIR light. The refracted light is examined and analyzed, and its results used for identification.

A NIR spectrophotometer not only identifies an object, it also identifies what that object is made of. So if you put a rock into the machine, it’s going to tell you exactly what type of rock it is, what types of rock are embedded within it, and what sample of rock it matched in the machine’s database.

NIR spectroscopy is becoming more popular in several fields. Medicine, food and agriculture, crime-solving—all of these fields are finding uses for NIR spectroscopy and are utilizing ways to advance the technology further. For more information, you can visit wisegeek.com/what-is-near-infrared-spectroscopy.htm.