What is a Laser?
A laser uses a range of optical amplifications to emit light. The device uses stimulated emission which is the process where an inbound photon interacts with and excited atomic electron resulting the decrease of at least one energy level. The energy released by the drop in energy level is moved onto the electromagnetic field which results in a new photon of identical phase, frequency, direction, and polarization of the incident wave. This stimulated emission process is actually part of the acronym laser: Light Amplification by Stimulated Emission of Radiation (laser).
Lasers have been heavily innovated as technology has advanced to the point where laser technology is commonplace in numerous different industries. Semiconductor lasers, Dye lasers, Photonic crystal lasers are just three of many different complicated laser technologies available on the market. There are so many different types of lasers and thus there are equally as many different industries that can use them. The medical industry uses lasers for Bloodless surgery, laser healing, eye surgery etc. Lasers are used in industry for cutting, materials heat treatment, and welding plus many more. The military use lasers for marking targets for bombing runs, guiding missiles, as well as simply to blind or confuse enemy troops. An example of military use of lasers is Boeing’s new technology explained in the video below:
Lasers & The Law
Police can use laser technology to help in fingerprint detection. Most security and customs at airports around the world use laser reading fingerprint scanners for all new arrivals into the country. Computers can then scan any fingerprints found at crimes scenes and compare them to the database of fingerprints on file allowing police to quickly identify who was at the scene. This process has led to many successful convictions and has saved numerous lives but removing dangerous criminals from the streets. Lasers also have a use in laboratory research. Lasers are used in chemical spectroscopy for identification of component molecular groups. Different functional groups such as ketones and aldehydes have different responses to the laser in terms of frequency allowing them to be easily identified on the resulting paper printed wavelengths.
Safety is important when using lasers. Laser technology, like all technology, has its dangers. It’s very important to ensure all safety protocol is adhered to when using any technology that includes lasers. The main hazard of lasers is damage to eyesight. Even the least powerful lasers can cause eye damage so it is very important to ensure that safety glasses are worn at all times. Lasers are classed into five different categories of safety. Class 1 lasers are defined as inherently safe as the laser is contained. An example of a class 1 laser type is a printer, CD player, or a DVD player. Class 2 lasers are safe during general use and won’t cause damage as the blink reflex of the eye is able to shield against it. An example of a class 2 laser is a laser pointer. Class 3R lasers can cause small damage to the eye but are a low risk as damage to the retina will only be caused if the laser is starred at for several seconds. Class 3B lasers are able to cause damage to the eye on first contact. Finally Class 4 lasers are powerful enough to cause damage not only to the eye but also to the skin. This class of lasers includes the majority of industrial and scientific lasers. An example of the use of this class of laser beam is for laser cutting of thick metal objects.