The many different applications of laser devices
The light beam that lasers produce is monochromatic. Monochromatic means that the beam is in one wavelength which means it will be in one colour. Since the light is in one colour, the absorption or reflection of the beam can be controlled (van Kessel 204). For example, during eye surgeries, the light beam can pass into the eyeball but only be absorbed by the disconnected retina’s blood vessels (van Kessel 204). The burning of these vessels will cause tissue scarring which causes the retina to be attached again; this provides the patient with clear vision once more (van Kessel 204).
Chemical, Gas, and Quantum Cascade Lasers
In addition, laser beams are very straight and constricted. This allows for it to generate a very concentrated, powerful beam that is able to cut holes in metals or even reach a mirror situated in outer space (Farndon). Different types of lasers have different functions. One type of laser uses hydrogen fluoride in the liquid state. This is a chemical laser and it is used in machines and weapons as it is able to give off a very powerful beam (Farndon).
Furthermore, there are also gas lasers. Gas lasers such as ones that use argon are able to emit a beam that is at a lower power. This allows the laser to be used by optometrists for surgeries involving the eye (Farndon). Also, there is a type of laser that uses a semiconductor; this is called a quantum cascade laser (Lipkin). Atoms in semiconductors have full valence electrons. When only a little energy is added, electrons in a semiconductor move very easily to the next atom (van Kessel 272). The quantum cascade laser is very small and less expensive to produce. This helps make it more economical and accessible to our society (Lipkin). Laser ablation
Laser ablation is the process of removing materials with a laser beam. The science behind this technology is that the high energy of the UV photons from the laser is able to break the chemical bonds that make up the material (Schaeffer). Factors that affect laser ablation are the wavelength and pulse rate of the laser. Also the type of material being removed matters as different materials have different bonds; some atomic bonds are stronger than others (Schaeffer). For example, covalent network crystals are some of the hardest materials ever to be found; they are connected by covalent bonds. Molecular crystals on the other hand, are relatively weaker as they are composed of van der Waal forces and hydrogen bonds (van Kessel 273). Recall that van der Waal forces and hydrogen bonds are intermolecular forces; this means that they are bonds between two molecules (van Kessel 257). Covalent or ionic bonds are bonds that are made between atoms; therefore, they are stronger and harder to break apart than the intermolecular forces (van Kessel 257).
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