• Tunable light sources are required in many optical Tunable lasers are more convenient from operational view point because of following advantages –
    • Only one transmitter part.
    • Independent of operating wavelength
    • It reduces number of different parts to be stocked and handled
    • Capable of being tuned over 8 nm to 20 wavelengths.
    • Wavelength tuning without changing output power.


  • Different tunable lasers are -

1 Vertical cavity surface emitting lasers

  1. Mode locked lasers

Recommended Questions


  1. With a neat sketch explain WDM scheme.
  2. State the significance of passive components in WDM.
  3. Explain the construction and working of 2 x 2 fiber
  4. Explain various performance parameters of optical
  5. Explain star coupler used in fiber optics.
  6. Briefly discuss DWDM with a simple sketch.
  7. Explain MZI
  8. Derive an expression for difference in length for MZI multiplexer
  9. Explain the need of isolator in optical network. Give its principle of operation
  10. Describe the use of circulator in optical How demultiplexer can be implemented using fiber grating and circulator?
  11. What is a tunable optical filter?
  12. Explain system parameters for tunable optical
  13. Explain the construction and application of dielectric thin film filter (TFF).
  14. Write a note on optical add/drop multiplexer.
  15. Write a note on tunable lasers