Free Online Course Materials. An Open Access Resource of In-Depth Information, Free Articles, Nonlinear and Fiber Optics. Laser. Red (660 & 635 nm), green (532 & 520 nm) and blue-violet (445 & 405 nm) lasers Among their many applications, lasers are used in optical disk drives, laser printers, and barcode scanners; fiber-optic and free-space optical communication; laser surgery and skin treatments; cutting and welding materials; military and law enforcement devices for marking targets and measuring range and speed; and laser lighting displays in entertainment.
Fundamentals Lasers are characterized according to their wavelength in a vacuum. Most "single wavelength" lasers actually produce radiation in several modes having slightly differing frequencies (wavelengths), often not in a single polarization. Although temporal coherence implies monochromaticity, there are lasers that emit a broad spectrum of light or emit different wavelengths of light simultaneously. Public Safety 101: What Not to Do With Lasers - Kasia Cieplak-Mayr von Baldegg - Video.