Laser communication and use of laser communication

Use of laser communication

1. LASER Communication SUBMITTED BY :: N.SRUTHI

2. Contents : Introduction Why LASER ? Principles and working of LASER Types of LASER’s Block diagram of LASER communication LASER Transmitter LASER Receiver Advantages Disadvantages Applications Conclusion References

3. Introduction Laser communications systems are wireless connections through the atmosphere. They work similarly to fiber optic links, except the beam is transmitted through free space. While the transmitter and receiver must require line-of-sight conditions, they have the benefit of eliminating the need for broadcast rights and buried cables. " Light Amplification by Stimulated Emission of Radiation "

4. Why LASER ?? Optical fiber link Direct Laser Link

5. Principles and working of LASER Absorption Spontaneous emission Pumping and population inversion Stimulated emission of laser

6. ABSORPTION SPONTANEOUS EMISSION PUMPING AND POPULATION INVERSION STIMULATED EMISSION

7. Types of LASERS Solid-state Laser-- ruby Laser ; color center Laser; nd:YAG Laser Gas Laser -- He-Ne Laser ; CO 2 Laser Liquid Laser -- Dye Laser Semiconductor Laser--hetero junction Laser ; homo junction Laser

8. SOLID LASER Ruby LASER ND:YAG

9. GAS LASER He-Ne LASER E CO 2 LASER

10. LIQUID LASER

11. SEMICONDUCTOR LASER Homo junction laser Hetero junction laser

12. BLOCK DIAGRAM OF LASER COMMUNICATION

13. Laser Transmitter : The Transmitter involves a signal processing circuit and a laser diode. A laser diode is used to create the laser signal. Laser Diodes include Photodiodes for feedback to insure consistent output.

14. Laser Receiver The LASER detectors may be: PIN diodes Avalanche Photo Diodes(APD) Single or multiple detectors The receiver involves the laser detector and signal and signal amplifying circuit.

15. Advantages Ease of deployment Can be used to power devices License-free long-range operation High bit rates Immunity to electromagnetic interference Full duplex operation Increased security when working with narrow beam(s) No Fresnel zone necessary

16. Disadvantages Beam dispersion Atmospheric absorption Rain Fog Snow Scintillation Interference from background light sources (including the Sun) Pointing stability in wind Pollution / smog

17. Applications SPACE COMMUNICATION FREE SPACE OPTICAL COMMUNICATION

18. Other applications are: Defense and Sensitive Areas Airport Runways Digital data transmission Medicine

19. Conclusion :: LASER would be visible or invisible , where visible laser may destroy everything and invisible can create anything

20. References :

21. Thank you