This document discusses biomedical sensors that use optical fibers. It introduces fiber optic sensors and their advantages, such as flexibility, lightness, safety, and immunity to electromagnetic interference. It then describes several specific fiber optic sensors: a pressure sensor that uses a Fabry-Perot cavity, temperature sensors that use phase interference or fiber deformation, and a blood flow sensor that uses laser Doppler flowmetry. Commercially available products are provided as examples for the pressure, temperature, and blood flow sensors. The document concludes that fiber optic sensors are well-suited for a variety of medical measurements due to their low cost, ease of use, and performance comparable to electric sensors.

1. Biomedical sensors using optical
fibers
Presented to: Prof. Sharaf El-Din ElNahas
Preaented by: Eng. Sherif Mohamed
Ibrahim

2. Contents:
1.
2.
3.
4.
5.
6.
7.
2
Why Using Optical Sensor.
Characteristics of FOSS .
Pressure Sensor.
Temperature Sensor.
Blood Flow.
Conclusion.
References.
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

3. Why Using Optical Sensors
 If the electronics must be located far from the
bedside.
 Immunity
to
electromagnetic
interferences
generated from the electronics equipment.
 They can be easily installed in areas which are
difficult to reach.
 Another property is the absence of crosstalk
between close fibers.
3
Introduction
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

4. Why Using Optical Sensors
 They perform as well as or better than electric
instrumentation.
 Fiber-optic sensors is attractive for the measurement
of a wide variety of physical and chemical
parameters.
 Fiber Optic Sensors (FOSS), being relatively easy to
manufacture and therefore inexpensive
4
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

5. Characteristics of FOSS
• Flexibility.
• Lightness.
• Suitable material, glass or plastic.
• Non-toxic and can be used for continuous
measurements.
• Safety for the patient, ensured by optical fiber
dielectricity and by the low light power used for
sensing purposes.
• low-cost installation and maintenance.
5
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

6. Pressure Sensor
Optical Pressure Sensor System
 Light Source.
 Detector.
 Coupler.
 Sensor Head (Fabry–Perot cavity).
6
Introduction
Pressure
Pressure
Sensor
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

7. Pressure Sensor
Optical Pressure Sensor System
 Main measurement requirements:
 a working range from −50 to 300 mmHg.
 a sensitivity of at least 0.1 mmHg.
 an accuracy of at least 1%
7
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

8. Pressure Sensor
 The Fabry–Perot cavity
 Glass cube
having a
partially
etched face.
 A pressure
sensitive
silicon
diaphragm.
 Fiber Optic
Coupler.
8
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

9. Pressure Sensor
Pressur
e
d
Light
Optical Fiber
Cavity Diaphragm
 The intensity of the reflected light and the phase
between them provides a pressure measurement
9
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

10. Pressure Sensor
 Manufactured by the American company Camino
Labs
CAMINO V420 PRESSURE MONITOR
10
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

11. Temperature Sensor
 Fiber optic thermometers are used when
electrical insulation and EM immunity are
necessary
 There are basically two approaches by means of
which one can easily measure temperature. They
are:
 Using Phase Interference.
 Using Fiber Deformation.
11
Introduction
Pressure
Sensor
Temperatur
Temperature
e Sensor
Sensor
Blood Flow
Conclusion
References

12. Temperature Sensor
 Using Phase Interference:
By measuring the phase difference between two reflected
beams of light, one can easily determine temperature.
12
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

13. Temperature Sensor
 Using Fiber Deformation:
13
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

14. Temperature Sensor
 The fiber optic thermometer commercialized by The
American company Luxtron
Luxtron 812 : an 2-channel fiber-optic temperature
sensor.
14
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

15. Blood flow
 Laser Doppler Flowmetry
15
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Blood Flow
Conclusion
References

16. Blood flow
16
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

17. Blood flow
17
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

18. Blood flow
18
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

19. Blood flow
 An instrument that is widely used in the clinical
practice is produced by The Swedish company
Perimed.
PeriFlux System 5000 : the
instrument for fiber-optic laser
Doppler flowmetry.
19
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
References

20. Conclusion
 Fiber-optic sensors is attractive for the




20
measurement of a wide variety of physical and
chemical parameters.
low-cost installation and maintenance.
In more cases better than electric
instrumentation.
Lower cost.
Can be easily managed by both doctors and
patients.
Introduction
Pressure
Sensor
Temperature
Sensor
Blood Flow
Conclusion
Conclusion
References

21. References
 Papers
1.
2.
3.
4.
21
Introduction
Anna Grazia Mignaniy and Francesco Baldini
1995, Biomedical sensors using optical fibres, Istituto di
Ricerca sulle Onde Elettromagnetiche ‘Nello Carrara’ 64, I50127, Italy.
M.Życzkowski, B.Uziębło-Życzkowska, L.Dziuda
K.Różanowski 2007, BIO-MEDICAL SENSIG USING FIBER
OPTIC SENSORS, Military University of
Technology, Institute of Optoelectronics, Kaliskiego Str.
2, 00-908 Warsaw, Poland.
Qingxu YU and Xinlei ZHOU 2011, Pressure Sensor Based
on the Fiber-Optic Extrinsic Fabry-Perot
Interferometer, School of Physics and Optoelectronic
Technology, Dalian University of
Technology, Dalian, 116023, P.R. China.
Lee C.L. Chin, William M.Whelan, and I. Alex Vitkin
2011, Optical Fiber Sensors for Biomedical
Applications, Optical-Thermal Response of Laser-Irradiated
Tissue, 2nd ed., Temperature
DOI 10.1007/978-90-481-8831Pressure
Blood Flow
Conclusion
References
References
Sensor
4_17,Sensor
Physics Department, Odette Cancer
Centre, Toronto, ON, Canada

22. References
 Review Article
1.
Dakshita Joy Vaghela, Ashish Amit Sinha 2011, Pulse
oximetry and laser Doppler flowmetry for diagnosis of
pulpal vitality, Departments of Conservative Dentistry
and Endodontics and Pedodontics, Kothiwal Dental
College Research Centre and Hospital, Moradabad,
India
 Websites
Blood Flow Meters - Young Do Medical Instruments
Co.,Ltd, retrieved 2007.
2. Producer fiber optical thermometers - Optocon AG.
retrieved 10 April 2012.
3. Fiber Optic Thermometers – AutomationWiki. retrieved
Pressure
Temperature
Introduction 26 February 2013.
Blood Flow
Conclusion
References
Sensor
Sensor
1.
22

23. Thank You
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