FBG based novel sensor design for low vacuum measurement with high sensitivity

This article demonstrates use of a fiber Bragg grating (FBG) sensor for in situ monitoring of vacuum process with high sensitivity. The sensor head consists of a commercial syringe barrel with plunger, metal spring, pressure chamber, FBG and safeguarding outer tube. The sensor is configured by firmly fixing the FBG between the plunger and the rigid support provided to the safeguarding tube. Under vacuum process the metal spring facilitates the FBG to get strained in axial direction which results in shift of Bragg wavelength of FBG. The Bragg wavelength shift of FBG is found to be linear with respect to vacuum pressure with a linear coefficient of 0.9988. Pressure sensitivity of the sensor is found to be 27 pm/cm Hg. The sensor design is simple, low-cost and has the advantage of all fiber optic sensors.

[1]  Hong Zhou,et al.  Study of a high-temperature and high-pressure FBG sensor with Al2O3 thin-wall tube substrate , 2008 .

[2]  Kyriacos Kalli,et al.  Fiber Bragg Gratings: Fundamentals and Applications in Telecommunications and Sensing , 2000 .

[3]  Yuliya Semenova,et al.  High resolution temperature insensitive interrogation technique for FBG sensors , 2010 .

[4]  Sai Shankar Madhuvarasu,et al.  A high sensitive FBG pressure sensor using thin metal diaphragm , 2014 .

[5]  R. Kashyap.  Fiber Bragg Gratings , 1999 .

[6]  Gopalkrishna M. Hegde,et al.  Fiber Bragg grating sensors for real-time monitoring of evacuation process , 2009, International Conference on Experimental Mechanics.

[7]  Xueguang Qiao,et al.  Study of simultaneous measurement of temperature and pressure using double fiber Bragg gratings with polymer package , 2005 .

[8]  Yan Wang,et al.  Study on high‐temperature and high‐pressure measurement by using metal‐coated FBG , 2008 .

[9]  Srimannarayana Kamineni,et al.  Characterization of Encapsulating Materials for Fiber Bragg Grating-Based Temperature Sensors , 2014 .

[10]  Michael A. Davis,et al.  Fiber grating sensors , 1997 .

[11]  Sai Shankar Madhuvarasu,et al.  Fiber Bragg grating-based high temperature sensor and its low cost interrogation system with enhanced resolution , 2014 .

[12]  Yage Zhan,et al.  Fiber Bragg grating temperature sensor for multiplexed measurement with high resolution , 2004 .

[13]  Qi Jiang,et al.  Hydraulic pressure sensor based on fiber Bragg grating , 2011 .

[14]  Yunjiang Rao,et al.  Strain sensing of modern composite materials with a spatial/wavelength-division multiplexed fiber grating network. , 1996, Optics letters.

[15]  Putha Kishore,et al.  Vibration sensor using 2 × 2 fiber optic coupler , 2013 .

[16]  L. Reekie,et al.  Optical fibre sensor for high pressure measurement using an in-fibre grating , 1993 .

[17]  Bo Liu,et al.  Review of fiber Bragg grating sensor technology , 2011 .