Spectrometer
The spectrometer is an instrument that allows to measure the spectrum of the electromagnetic radiation, namely the properties of light as a function of it's wavelength. The majority of spectrometers uses the principle of interference to decompose the light radiation in it's wavelength and measuring it's intensity with a photodiode.
Spectrometers have a very wide range of applications that reflects the diversity of types and characteristics of these instruments. Applications range from the physical cosmology of engineering materials. Normally spectrometers are divided according to their resolving power and the section of the light spectrum that can be measured (visible, UV, X-rays, microwaves, etc..).
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With this tool, we can quickly assess any type of metal.