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![SENSING DETAILS
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](https://image.slidesharecdn.com/opticalsensorsandtheirapplications-241205100847-990963b6/85/optical-sensors-and-their-applications-ppt-7-320.jpg)
optical sensors and their applications.ppt
- 1. OPTICAL SENSORS AND THEIRAPPLICATIONS 1
- 2. TOPICS INCLUDED INTHIS PRESENTATION INTRODUCTION WHY OPTICAL SENSORS ? PRINCIPLE OF OPTICAL SENSORS CLASSIFICATION AND COMPARISON SOME INTERESTING APPLICATIONS WHERE DO WE GO FROM HERE ? 2
- 3. INTRODUCTION NEW REVOLUTIONOF OPTICAL FIBER SENSORS IT IS A “SPIN-OFF” FROM OTHER OPTICAL TECHNOLOGIES SEEING THE POTENTIAL IN SENSING APPLICATIONS – DEVELOPED AS ITS OWN FIELD 3
- 4. WHY OPTICAL SENSORS ELECTROMAGNETIC IMMUNITY ELECTRICAL ISOLATION COMPACT AND LIGHT BOTH POINT AND DISTRIBUTED CONFIGURATION WIDE DYNAMIC RANGE AMENABLE TO MULTIPLEXING 4
- 5. 5 TEMPERATURE CHEMICAL SPECIES PRESSURE FORCE FLOWRADIATION LIQUID LEVEL pH DISPLACEMENT HUMIDITY VIBRATION STRAIN ROTATION VELOCITY MAGNETIC FIELDS ELECTRIC FIELDS ACCELERATION ACOUSTIC FIELDS OPTICAL SENSOR MEASURANDS
- 6. 6 WORKING PRINCIPLE • LIGHTBEAM 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
- 7. SENSING DETAILS EP (t)cos[ωt+θ(t)] • INTENSITYBASED SENSORS – EP (t) • FREQUENCY VARYING SENSORS - ωP (t) • PHASE MODULATING SENSING- θ(t) • POLARIZATION MODULATING FIBER SENSING 7
- 8. CLASSIFICATION EXTRINSIC SENSORS 8 WHERETHE LIGHT LEAVES THE FEED OR TRANSMITTING FIBER TO BE CHANGED BEFORE IT CONTINUES TO THE DETECTOR BY MEANS OF THE RETURN OR RECEIVING FIBER
- 9. CLASSIFICATION (contd.) INTRINSICSENSORS 9 INTRINSIC SENSORS ARE DIFFERENT IN THAT THE LIGHT BEAM DOES NOT LEAVE THE OPTICAL FIBER BUT IS CHANGED WHILST STILL CONTAINED WITHIN IT.
- 10. COMPARISON OF THETWO TYPES EXTRINSIC INTRINSIC APPLICATIONS- TEMPERATURE, PRESSURE,LIQUID LEVEL AND FLOW. LESS SENSITIVE EASILY MULTIPLEXED INGRESS/ EGRESS CONNECTION PROBLEMS EASIER TO USE LESS EXPENSIVE APPLICATIONS- ROTATION, ACCELERATION, STRAIN, ACOUSTIC PRESSURE AND VIBRATION. MORE SENSITIVE TOUGHER TO MULTIPLEX REDUCES CONNECTION PROBLEMS MORE ELABORATE SIGNAL DEMODULATION MORE EXPENSIVE 10
- 11. SENSOR TYPES 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
- 12. STRAIN SENSORS FIBERBRAGG GRATINGS (FBG) TECHNOLOGY SENSES AS LITTLE AS 9 MICROSTRAIN NRL and UNITED TECHNOLOGY RESEARCH BIOMEDICAL SENSORS SPECTROSCOPIC BIOMEDICAL SENSORS CO 2, O 2 and pH CAN BE MEASURED SIMULTANEOUSLY FLOW MONITORING BY LASER DOPPLERIMETRY 12
- 13. ELECTRICAL AND MAGNETIC SENSORS APPEALING- INHERENT DIELECTRIC NATURE LESS SENSITIVE TO ELECTROMAGNETIC INTERFERENCE SMALL SIZE AND SAFER THEY ARE ALMOST ALWAYS HYBRID ABB CORPORATION RESEARCH CENTER ROTATION SENSOR BASED ON THE SAGNAC EFFECT 13
- 14. TWO TYPESRING LASER GYROSCOPE (RLG) AND FIBER OPTIC GYROSCOPE (FOG) US COMPANIES PURSUING HIGH PERFORMANCE FOG’s (HONEYWELL, LITTON, NORTHRUP, ALLIED SIGNAL etc.) PRESSURE SENSORS EARLIER BASED ON PIEZORESISTIVE TECHNIQUE BASED ON MOVABLE DIAPHRAGM HIGH PERFORMANCE- (POLARIZATION BASED SENSORS) OPERATING PRESSURE RANGES FROM 0- 70,000 torr 14
- 15. DISPLACEMENT AND POSITION SENSORS ONE OF THE FIRST OPTOELECTRONIC SENSORS TO BE DEVELOPED. SIMPLE SENSORS RELY ON THE CHANGE IN RETROREFLECTANCE DUE TO A PROXIMAL MIRROR SURFACE ALSO REFERRED AS LIQUID LEVEL SENSORS 15
- 16. APPLICATIONS MILITARY ANDLAW ENFORCEMENT 16 THIS SENSOR ENABLES LOW LIGHT IMAGING AT TV FRAME RATES AND ABOVE WITHOUT THE LIMITATIONS OF VACUM TUBE BASED SYSTEMS.
- 17. NIGHT VISION CAMERA(contd.) COMPRISES OF : AMPLIFIED CCD SENSOR ANTI BLOOMING TECHNOLOGY CRYSTAL POLYMER SHUTTER ADVANTAGES : EXCEPTIONAL DAY LIGHT RESOLN. IMMUNE TO OVER EXPOSURE VERY HIGH CONTARAST LEVELS NO HALOING OR SCINTILLATIONS 17
- 18. BIOMETRICS YOUR FACE, FINGERSAND EYES IN A WHOLE NEW LIGHT 18 • IMAGE CAPTURE • IMAGE PROCESSING • FEATURE EXTRACTION • FEATURE COMPARISON
- 19. PARTIAL DISCHARGE DETECTION USESOPTICAL FIBER SENSORS 19 OPTICAL FIBER SENSORS ARE BEING TESTED FOR USE IN DETECTING PARTIAL DISCHARGES IN ELECTRICAL TRANSFORMERS. PINPOINTING SUCH DISCHARGES IS ESSENTIAL TO PREVENTING INSULATION BREAKDOWN AND CATASTROPHIC FAILURES.
- 20. LETS TAKE ALOOK AT THE CHRONOLOGY OF OPTICAL SENSORS 20
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- 23. GEOGRAPHICAL ORIGIN OF OPTICALSENSOR PATENTS 23
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- 25. CONCLUSIONS LOOKING AT THEINDUSTRY TRENDS IN THE PAST 2 DECADES AND THE EXPONENTIAL CURVE IT SEEMS TO ME THAT THERE IS GOING TO BE A LOT OF RESEARCH AND IMPROVEMENTS TO THE EXISTING SENSORS OPTICAL SENSORS ARE HERE TO STAY !!!! 25
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- 27. REFERENCES Optical SensorTechnologies www.wtec.org/loyola/opto/c6_s3.html Measuring with LIGHT www.sensorsmag.com/articles/0500/26main.html Optical Fiber Sensors www.ul.ie/elements/Issue6/Optical%20Fibre %20Sensors.html Partial Discharge Detection http://www.photonics.com/spectra/applications/XQ/ ASP/aoaid.328/placement.HomeIndex/QX/read.html Military and Law Enforcement http://www.militaryandlaw.com.au/products/l3vision.php 27
- 28. Pockels Effect www.scienceworld.wolfram.com/physics/ PockelsEffect.html Distinctive advantages give optical sensors the edge over conventional systems www.eurekalert.org/pub_releases/ 2003- 08/ti-dag081303.php 28
- 29. THANK YOU FORYOUR PATIENCE AND TIME 29