Answer: LASER (Light Amplification by Stimulated Emission of Radiation)
A laser is a device that works by the principles of optics that emits a monochromatic light beam (of a single wavelength), coherent and with high intensity. Being this possible thanks to the electrical or thermal stimulation of atoms of a specific material and, on which the color of the emitted light will depend.
Basically, this instrument concentrates the light in a narrow beam and emits it in a concentrated and coherent form.