What Is a Spectrometer?

• A spectrometer is a device that breaks light into a spectrum, which is the light's collection of component colors, all of which make up the color of the light as a whole. These spectra are different for every element. This means that by recording the spectra of different elements, one can obtain a reliable method for identifying elements based on the spectra observed. If a certain spectrum is similar to the spectrum of a known element, it can be said that the observed element is that known element. This method of identification puts spectrometers as one of the most important technologies in sciences such as astronomy and chemistry.
  
  

The Components of a Spectrometer

• A spectrometer is a surprisingly simple device that could even be made at home. It starts with some way of collecting light from an object and directing that light onto a diffraction grating or spectrum. The diffraction grating or spectrum leads light onto mirrors, which direct the light to either a charged coupled device (CCD) chip, which can record the light, or a flat surface, off of which the spectrum can be read.
  
  

How the Spectrometer Does Its Job

• The light coming from the object is filtered into a very thin sliver of light by a collector, which can be as simple as a mere slit in a piece of paper. This thin sliver of light hits a prism or diffraction grating, which splits the light into spectral lines of color, representing the object's spectrum. This spectrum is reflected off mirrors until it reaches the CCD chip or flat surface. When it reaches one of those, the spectral lines can be identified by wavelength. The wavelength of a color depends on what that color is. For instance, red has a higher wavelength than blue. If the spectrometer uses a CCD chip, then it is usually connected to a computer. The CCD chip can send the image it receives to the computer, which then analyzes the spectrum and possibly graphs it based on the amount of each wavelength of light apparent in the image.