Download Trends in Optical Fiber Sensors - IEEE Bombay Section Symposium

Trends in Optical Fiber Sensors
19/10/2015 17:30
Eagle Photonics Solutions
Philip B. Kassey
Head, R&D
[email protected]
Brief History
The first attempts at guiding light on the basis of total internal reflection in
a medium dates to
1841 by Daniel Colladon. He attempted to couple light from an arc lamp
into a stream of water
In 1930 the medical student
Heinrich Lamm of Munich produced
the first image transmitting fiber
bundle.
The well-known scientists
A.C.S. van Heel, Kapany and
H.H.Hopkins produced the first fiber
optic endoscope on the basis of fiber
cladding in 1954.
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What is Fiber ?
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TOTAL INTERNAL REFLECTION
(TIR)
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Major Applications Of Fiber Optics
Fiber Optics in Medical- Endoscopy
Fiber Optics in Communication
Fiber Optics in Sensors
Typical Optical Fiber Measurement
System
Photo-detector
Light source
Focus
lens
Sensing
element
How they work
 Fiber optic sensors
measure properties of
their environment.
 They can measure
anything which
changes the way light
travels through the
fiber, or alters the
light’s properties.
What can they measure?
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Temperature
Pressure
Strain
Displacement
Acceleration
Flow rate
Vibration
Chemical concentrations
Electrical and Magnetic Fields
Rotation rate
Sensor Types
Chemical Sensors
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Remote Spectroscopy
Temperature Sensors
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Largest Commercially Available Sensors
Range -40 Deg C To 1000 Deg C
Strain Sensors
Fiber Bragg Gratings (FBGs) Technology
 Long Period Gratings (LPGs)
 Extrensic Fabry Perot Interferometric (EFPI)
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Biomedical Sensors
Spectroscopic Biomedical Sensors
 CO 2, O 2 and pH Can Be Measured Simultaneously
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Electrical And Magnetic Sensors
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Appealing- Inherent Dielectric Nature
Less Sensitive To Electromagnetic Interference
Rotation Sensor
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Based On The Sagnac Effect
Two Types Ring Laser Gyroscope (Rlg) And Fiber
Optic Gyroscope (Fog)
Pressure Sensors
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Earlier Based On Piezoresistive Technique
Displacement And Position Sensors
Simple Sensors Rely On The Change In
Retroreflectance Due To A Proximal Mirror Surface
 Also Referred As Liquid Level Sensors
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Methods of Measurement
 Amplitude and Intensity-Based Sensors
 Frequency and Wavelength-Varying Sensors
 Polarization and Phase-Modulating Fiber-Optic
Sensing
Intensity-Based Sensors
 Detect changes in
light intensity,
correlate change to
change in
pressure, or
temperature, etc.
• These systems have a poor ability to screen
noise, leading to lower precision, but are
simple and inexpensive systems.
Frequency- and Wavelength-Varying
Sensors
 Light changes in frequency or wavelength to
parameter of interest.
 Low alteration of signal outside of sensing area.
 Wavelength measurement is very sensitive; not
strongly affected by light loss in connections, or
source intensity fluctuations.
Wavelength-Varying Sensors…
 Fiber Bragg Grating: most common type.
 Characteristic reflected light wavelength
dependent on grating spacing. Stress applied to
fiber changes spacing.
Polarization and Phase-Modulating FiberOptic Sensing
 Polarization modulation sensors are the most
complicated and delicate instruments.
 Use Faraday Effect to measure magnetic fields,
by measuring polarization rotation.
 Polarization unintentionally altered by other
processes: bending, stretching, and twisting
causes problems.
Advantages of Fiber Sensors
 Large Bandwidth
 Efficient Transmission (Low Loss)
 Immunity To EMI/ RFI
 Security Of Information
 Both Point And Distributed Sensing
 Corrosive environments- silica fiber
 Small Size And Lightweight
 Flexibility
 Resistant To Hostile Environments
 Freedom From Cross-talks
 No Sparking And Fire Hazards
 Single Fiber Serves Both As Sensor And Data Comm..
 Multiplexing & Spatially Distributed Sensing
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 High Performance
New Trend of Optical Fibers
in Musical Instruments
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Optical Fiber Guitar
Developed at Ecole Polytechnique de Montreal, Canada with the
supervision of Prof.Raman Kashyap
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19/10/2015
COMMERCIALISED APPLICATIONS
Fencing Fiber-based Intrusion
Detection
The FIDS System Provides:
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Highly reliable and sensitive system
Virtually 100% Detection Rate
Negligible False Alarm rate
Negligible Nuisance Alarms
Highest Performance-to-Cost Ratio
Alarm Activation only by Direct Assault
Low sensitivity to climatic conditions
Immunity from electrical interference
Environmentally Esthetic Appearance
Long-life Guarantee
Uniform performance over long distances
Completely safe
Easy and fast to install
Fencing Based Intrusion Detection System
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Buried Fiber Optic
Intrusion Detection System
Speckle Image
Buried Multi-mode Fiber
Laser
CCD
Camera
PRINCIPLE
Speckle pattern is formed due to interference of various modes of propagating
light rays in multimode optical fiber cable which shifts if the cable is perturbed.
This shift in speckle pattern is analysed to detect intrusion
BELOW GROUND SENSOR CABLES CAN BE LAID INSTEAD
PERIMETER FENCES IF DETECTION IS THE PRIME OBJECTIVE
LANDSLIDE MONITORING USING FIBER OPTICS SENSORS
 Detection of Initiation & Early Warning
 Fiber Optic Microbend Sensors
 Hydrogel Fiber Optic Cable
 Remote Real Time Monitoring early stages of Landslides
 Photonic Techniques
of OTDR based sensing
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Micro bend based Landslide Monitoring &
Early Warning System Near Haridwar Mansa
Devi
Digital
Data
Link
Remote
Monitoring
and Control
Principle of OTDR
Incident light (Pulse)
Laser
Transmitted light
Detector
Fiber core
scattering light
Back scattering
light
z
Distance
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z = tV / 2
t : two-way propagation delay
time
V : velocity of light in the fiber
Strain Distribution
Strain (%)
Deformation
Grav
el
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
-0.2
Sand
Deformation
20mm
40mm
60mm
80mm
100mm
120mm
140mm
160mm
180mm
200mm
43m
42m
41m
40m
39m
38m
37m
36m
Distance from instrument (m)
35m
34m
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Optical Fiber Sensor Systems based on
Fiber Bragg Gratings :
FBG Sensors In Smart Skin
Applications
FBG SENSOR
EMBEDDED FBG SENSORS IN AIRCRAFT
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The SOFO displacement center shown here monitoring crack
development in the 17th century Gandria Church in
Switzerland.
EU project SMITS(Smart Monitoring in Train Systems):
High speed train on the French National Railway instrumented
with fiber optic contact force measurement (Paris, Vendome).
Optical Fiber Sensors in Power
Plants, Oil and Gas Pipe Lines
Sensors require no electrical power
and are immune to electrical
interference and
intrinsically safe
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Multiple measurands
(Strain, Temperature,
Pressure) on a single
fiber are possible.
Fiber Optic Tail Rotor Control System for ALHs
EFPI SENSORS FOR HEALTH MONITORING OF PROPELLER
BLADES OF AN ICEBREAKER
USCGS POLART STAR ICE BREAKER
FIBER OPTIC EFPI STRAIN GAGE
Fire Detection and Warning System for
Aircraft
Features
 µ controller Based Modular
Configuration
 SMA/Bimetal Sensor
 Fast Response
 Low Hysterisis
 Rugged & Compact
 Precise Hazardous Zone Isolation
 Actuation Temp. 3000c
Various Other Applications
On Chain Fences
On Walls
On Palisade Fences
Securing pictures in galleries
Surveillance of areas
Boarder Security
Optical Communications
Future Fiber to Home, all controlled by Fiber Optics
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THANK YOU FOR YOUR PATIENCE
Questions?
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Contact us at:
Eagle Photonics Pvt. Ltd.
Head Office :
Branch Office :
# 38, 22nd Main Road,
14th Cross, Padmanabhanagar,
Bangalore – 560070. India
Ph.: +91-80- 26395002, 26395003,
Fax. +91-80-26395003
Email: [email protected]
Website: www.eaglephotonics.com
Plot No: 31, First Floor, Sector- 19C,
Vashi, Navi Mumbai – 400705,
Maharashtra, India
Ph: +91 – 22- 27841425
Mob No: +91-9833073463