Lasers have applications in almost every field like medicine, industry, communication, and science and technology. These applications are due to the directional, coherent, and monochromatic properties of lasers. Let us discuss these applications one by one:

a) Holography:

Holography is a technique to record the complete picture of an object, that is it will produce a three-dimensional picture. The process of holography will be discussed in detail later on.

b) Measurement of long-distance:

The beam spreading in the laser light is very small, the laser can travel long distances, without appreciable spreading. The time taken by a laser pulse to travel from laser source to a given target and back is measured. As the velocity of light is known, the distance of the target can be calculated using the relation 2d =  c x  t where d is the distance of the target and c is the velocity of light.

c) Applications in scientific research:

Due to the coherent nature of laser light, many new optical phenomena have been observed using a laser. Using laser light we investigate the basic laws of interaction of atoms and molecules with electromagnetic waves.

d) Application in communication:

 In the fiber communication system, the laser beam is used. The rate at which information is transmitted is proportional to the bandwidth of the information carrier signal.

The bandwidth is proportional to the frequency of the carrier. Since the frequency range of laser signals is quite high compared to microwaves, large bandwidth can be obtained using the optical region as compared to the microwave region.

e) Applications in Industry:

Due to the high intensity of the laser beam, the laser can be used in welding, cutting, and in producing very high temperatures. The other advantage of a laser is that the beam can be focused onto a fine spot. The small spot size implies that high energy densities are possible. Lasers are also found suitable for machining and drilling holes.

f) Lasers in Isotope separation:

The light emerging from a laser is extremely monochromatic. When laser light falls on a mixture of two isotopes, the laser light excites the atoms of only one of the isotopes thus separating it from the other isotope.

In addition to the high monochromaticity, the high intensity of the laser is also responsible for its application for isotope separation because with low-intensity beams the separation rate would be too low for practical use.

g) Applications in Medicine:

i) Laser Surgery: The focused laser beam is capable of bloodless surgery since the beam not only cuts but also welds blood vessels being cut. Laser surgery is painless because operations are very fast and there is not enough time for the patient to respond to the incision and sense pain.

ii) Lasers in Opthalmology:  Lasers are used for several years to treat the detachment of the retina. The beam is focused on a certain point of the retina after it has passed through the lens of the eye and vitreous chamber without being absorbed in them. The green beam of laser is strongly absorbed by the red blood cells of the retina and the consequent thermal effects lead to reattachment of the retina. The operation is carried out by a 0.01-sec pulse and being very short, is virtually painless. Other illnesses treated by the focused laser beam are cataracts, tumors, and glaucoma.

iii) Laser Therapy:  He-Ne laser has produced a curing effect on trophic ulcers, poorly healing wounds, and bone fractures. The laser can also be guided through optical fiber into blood vessels to remove the clothing, in the case of heart patients, through heating. It has also found application in treating decaying teeth. The laser can replace dental drills.

The above are important applications of lasers in different fields, if you know more, please share in the comments section.