Optical Fibre Detector

9,810 views
9,418 views

Published on

Published in: Education
0 Comments
6 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
9,810
On SlideShare
0
From Embeds
0
Number of Embeds
6
Actions
Shares
0
Downloads
536
Comments
0
Likes
6
Embeds 0
No embeds

No notes for slide

Optical Fibre Detector

  1. 1. OPTICAL FIBER DETECTOR <ul><li>NAME:- SANDEEP KUMAR </li></ul><ul><li>CLASS:- B.TECH 4 th YEAR </li></ul><ul><li>BRANCH:- ECE </li></ul>
  2. 2. CONTENTS <ul><li>PHASE AND POLARIZATION FIBER SENSORS </li></ul><ul><li>INTRINSIC FIBER SENSORS </li></ul><ul><li>EXTRINSIC FIBER SENSORS </li></ul>
  3. 3. INTRODUCTION <ul><li>IT IS PART OF OPTICAL FIBER RECEIVER </li></ul><ul><li>IT CONVERTS OPTICAL SIGNAL INTO ELECTRICAL SIGNAL </li></ul><ul><li>THE ELCTRON EXCITED FROM VALANCE BAND TO CONDUCTION BAND </li></ul><ul><li>REQUIRED LOW BIAS VOLTAGE </li></ul>
  4. 4. PROCESS OF OPTICAL FIBER DETECTOR <ul><li>ABSORPTION: </li></ul><ul><li>TRANSPORTAION OF CARRIER: </li></ul><ul><li>GENERATION OF PHOTOCURRENT: </li></ul>
  5. 5. PARAMETERS OF OPTICAL FIBER DETECTOR <ul><li>Responsivity : </li></ul><ul><li>Quantum Efficiency : </li></ul><ul><li>Capacitance : </li></ul><ul><li>Response Time : </li></ul><ul><li>Long wavelength cutoff : Wavelength = hc/Eg </li></ul><ul><li>noise equivalent power (NEP) : </li></ul><ul><li>detectivity : </li></ul>Figure 1— C-V Curve
  6. 6. PRINCIPLE OF OPERATION <ul><li>When a photon strikes the </li></ul><ul><li>diode, it excites an electron , </li></ul><ul><li>creating a mobile electron and a positively charged hole. </li></ul><ul><li>If absorption occurs in </li></ul><ul><li>depletion region,or diffusion length ,carriers are swept from the junction by built-in field .photocurrent is accured </li></ul>
  7. 7. TYPES OF OPTICAL FIBER DETECTOR <ul><li>THE OPTICAL FIBER DETECTOR IS BASICALLY THREE TYPE :- </li></ul><ul><li>P-N PHOTODIODE </li></ul><ul><li>P-I-N PHOTODIODE </li></ul><ul><li>AVALANCHE PHOTODIODE </li></ul>
  8. 8. (1) P-N PHOTODIODE <ul><li>IF INCIDENT PHOTONS HAVE E p = hf =≥ E g </li></ul><ul><li>THEN ELECTRONS </li></ul><ul><li>MOVE FROM VALACE BAND TO </li></ul><ul><li>CONDUCTION BAND </li></ul>
  9. 9. (2) P-I-N PHOTODIODE <ul><li>it consists of a thick, lightly doped intrinsic layer sandwiched between thin p and n regions . </li></ul><ul><li>The word intrinsic means “natural”, “un-doped”. positive-intrinsic-negative . </li></ul>
  10. 10. PIN Photodiode
  11. 11. <ul><li>THE PIN PHOTODIODE IS TWO TYPES </li></ul><ul><li>(1) FRONT ILLUMINATION PD :- The light passes through the thin p region and generates electron-hole pairs in the thick intrinsic layer . </li></ul><ul><li>(2) REAR-ILLUMINATION PD :- light enters the active region through a heavily doped n + layer. This layer is transparent to the incident light because its energy gap is larger than the energy of incident photons. </li></ul>
  12. 13. (3)AVALANCHE PHOTODIODE <ul><ul><li>The free carriers created by absorbed photon . </li></ul></ul><ul><ul><li>A collision of carriers with </li></ul></ul><ul><ul><li>neutral atoms ,bound electrons </li></ul></ul><ul><ul><li>break out of the valence shell. </li></ul></ul><ul><ul><li>The secondary carrier accelerate and create new carriers. Require high-voltage </li></ul></ul>
  13. 14. AVALANCHE PHOTODIODE PROCESSS Figure 4 — APD
  14. 15. PARAMETERS OF AVALANCH PHOTODIODE <ul><li>IMPACT IONISATION COEFFICIENT </li></ul><ul><li>RESPONSE TIME </li></ul><ul><li>THRESHOLD IONISATION ENERGY </li></ul><ul><li>MULTIPLICATION FACTOR OR CURRENT GAIN </li></ul><ul><li>RESPONSIVITY </li></ul>
  15. 16. TYPES OF SENSORS <ul><li>PHASE AND POLARIZATION FIBER SENSORS </li></ul><ul><li>INTRINSIC SENSOR </li></ul><ul><li>(1)OPTICAL MICROBENDING </li></ul><ul><li>SENSOR </li></ul><ul><li>(2)OPTICAL FLOW METER </li></ul><ul><li>SENSOR </li></ul>
  16. 17. <ul><li>EXTRINSIC SENSOR </li></ul><ul><li>(1)OPTICAL FIBER LEVEL </li></ul><ul><li>DETECTOR </li></ul><ul><li>(2)PHOTOELASTIC PRESSURE </li></ul><ul><li>DETECTOR </li></ul><ul><li>(3)FLUOROPTIC TEMPERATURE </li></ul><ul><li>DETECTOR </li></ul><ul><li>(4)OPTICAL FIBER LASER DOPPLER VELOCIMETER </li></ul>
  17. 18. PHASE FIBER SENSOR
  18. 19. POLARIZATION FIBER SENSOR
  19. 20. FIBER MICROBENDING INTIRINSIC SENSOR
  20. 21. INTRINSIC OPTICAL FIBER FLOW METER
  21. 22. EXTRINSIC FIBER OPTICAL FLUID LEVEL DETECTOR
  22. 23. PHOTO ELASTIC PRESSURE SENSOR
  23. 24. FLUOROOPTIC TEMPERATURE SENSOR
  24. 25. FIBER LASER DOPPLER VELOCIMETER
  25. 26. THANK YOU VERY MUCH

×