Editing List of laser applications (section)

===Spectroscopy===
Most types of laser are an inherently pure source of light; they emit near-[[monochromatic]] light with a very well defined range of [[wavelength]]s. By careful design of the laser components, the purity of the laser light (measured as the "[[linewidth]]") can be improved more than the purity of any other light source. This makes the laser a very useful source for [[spectroscopy]]. The high intensity of light that can be achieved in a small, well collimated beam can also be used to induce a nonlinear optical effect in a sample, which makes techniques such as [[Raman spectroscopy]] possible. Other spectroscopic techniques based on lasers can be used to make extremely sensitive detectors of various molecules, able to measure molecular concentrations in the parts-per-10<sup>12</sup> (ppt) level. Due to the high power densities achievable by lasers, beam-induced atomic emission is possible: this technique is termed [[Laser induced breakdown spectroscopy]] (LIBS).