This document discusses optical fiber sensors, including their principles and classifications. Optical fiber sensors have advantages like electromagnetic immunity, electrical isolation, compact size, and ability to do distributed or multiplexed configurations. They can sense and measure changes in light intensity, phase, polarization, wavelength or spectral distribution. Optical fiber sensors are classified as extrinsic or intrinsic. Extrinsic sensors have the light leave the fiber to be altered before returning, while intrinsic sensors alter the light within the fiber. The document gives examples of applications for different types of optical fiber sensors such as temperature, chemical, pressure, and military sensors.

1. Bilal Mohammed Ziyadah

2. INTRODUCTION
WHY OPTICAL SENSORS ?
PRINCIPLE OF OPTICAL SENSORS
CLASSIFICATION AND COMPARISON
SOME INTERESTING APPLICATIONS
WHERE DO WE GO FROM HERE ?

3. • NEW REVOLUTION OF OPTICAL FIBER
SENSORS
• IT IS A “SPIN-OFF” FROM OTHER
OPTICAL TECHNOLOGIES
• SEEING THE POTENTIAL IN SENSING
APPLICATIONS – DEVELOPED AS ITS
OWN FIELD

4. • ELECTROMAGNETIC IMMUNITY
• ELECTRICAL ISOLATION
• COMPACT AND LIGHT
• BOTH POINT AND DISTRIBUTED
CONFIGURATION
• WIDE DYNAMIC RANGE
• AMENABLE TO MULTIPLEXING

5. •LIGHT BEAM CHANGES BY THE
PHENOMENA THAT IS BEING MEASURED
•LIGHT MAY CHANGE IN ITS FIVE OPTICAL
PROPERTIES i.e INTENSITY, PHASE,
POLARIZATION,WAVELENGTH AND
SPECTRAL DISTRIBUTION

6. EP(t)cos[ωt+θ(t)]
• INTENSITY BASED SENSORS – EP (t)
• FREQUENCY VARYING SENSORS - ωP(t)
• PHASE MODULATING SENSING- θ(t)
• POLARIZATION MODULATING FIBER SENSING

7. • EXTRINSIC SENSORS
WHERE THE LIGHT LEAVES THE FEED OR
TRANSMITTING FIBER TO BE CHANGED
BEFORE
IT CONTINUES TO THE DETECTOR BY MEANS
OF THE RETURN OR RECEIVING FIBER

8. • INTRINSIC SENSORS
INTRINSIC SENSORS ARE DIFFERENT IN THAT THE
LIGHT BEAM DOES NOT LEAVE THE OPTICAL FIBER
BUT IS CHANGED WHILST STILL CONTAINED WITHIN IT.

9. EXTRINSIC INTRINSIC
APPLICATIONS- ROTATION,
ACCELERATION, STRAIN,
ACOUSTIC PRESSURE AND
VIBRATION.
MORE SENSITIVE
TOUGHER TO MULTIPLEX
REDUCES CONNECTION
PROBLEMS
MORE ELABORATE SIGNAL
DEMODULATION
MORE EXPENSIVE
APPLICATIONS-TEMPERATURE,
PRESSURE,LIQUID LEVEL AND
FLOW.
LESS SENSITIVE
EASILY MULTIPLEXED
 INGRESS/ EGRESS
CONNECTION PROBLEMS
EASIER TO USE
LESS EXPENSIVE

10. CHEMICAL SENSORS
• REMOTE SPECTROSCOPY
• GROUNDWATER AND SOIL CONTAMINATION
• MAJOR PLAYERS IN CHEMICAL SENSORS
1) PHARMACIA BIOTECH (SWEDEN)
2) FIBERCHEM
3) THE QUANTUM GROUP
TEMPERATURE SENSORS
• LARGEST COMMERCIALLY AVAILABLE SENSORS
• RANGE -40 deg C TO 1000 deg C
• US-SMALL COMPANIES, JAPAN- HITACHI n SUMITOMO

11. MILITARY AND LAW ENFORCEMENT •
THIS SENSOR ENABLES LOW LIGHT IMAGING AT TV FRAME
RATES AND ABOVE WITHOUT THE LIMITATIONS OF VACUM TUBE
BASED SYSTEMS.