Laser
Videos
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word laser originated as an acronym for light amplifi
A researcher working on an optical system
A telescope in the Very Large Telescope system producing four orange laser guide stars
A laser can produce a very narrow beam of light of a single wavelength, in this case, green.
A helium–neon laser demonstration. The glow running through the center of the tube is an electric discharge. This glowing plasma is the gain medium for the laser. The laser produces a tiny, intense spot on the screen to the right. The center of the spot appears white because the image is overexposed there.
Gas laser
Videos
A gas laser is a laser in which an electric current is discharged through a gas to produce coherent light. The gas laser was the first continuous-light laser and the first laser to operate on the prin
A helium-neon laser is a well-known type of gas laser