LASERS- CHARACTERISTICS AND APPLICATIONS

LASER

“Light Amplification by Stimulated Emission of Radiation”

Characteristics of Laser:

1. Highly coherent:
All the electrons which are excited to the higher energy level jump to same lower energy level at the same time during lasing process(lasing action).
2. Laser is monochromatic:
The light consists single wavelength
3.Laser consists high intensity.
They can travel through any longer distance with out dispersion. 4. It propagates in the form a narrow beam.

laser can penetrate through water.
5. Laser consists directionality:
ordinary light propagates in all directions but laser propagates along one direction only.
6. Laser is not absorbed by water. ordinary light propagates in all directions but laser propagates along one direction only.

7. Laser produces heat and increase the temperature of the substance on which it incidents. A very high temperature about 100K can be produced using lasers.


Applications of Lasers:

1. Lasers are used in microwave communication due to their narrow band width used in radars, and satellite communications.
2. The distance between the earth and moon can be measured.
3. They are used for network communications under water.

4. Lasers are used to communicate the signals as optical guide in fiber optics.
5. In industries lasers are used to drill the holes in hard steel and diamonds.
6. Lasers area used in reading the bar code as scanner.
7. Lasers are used in medical field: removing the cataract and retina therapy of the eye, in cancer diagnosis, to melt the stones in kidneys, and also in cosmetology.
8. In defense lasers are used as high energetic weapons and in ranging the target. And also many applications in science and technology.
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for explanation :

https://youtu.be/pc8hiN89ZF8

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