Long Period Fiber Grating Humidity Sensor With Gelatin/Cobalt Chloride Coating

Author

Nidhi ; Tiwari, Usha ; Panwar, Nisha ; Kaler, R.S. ; Bhatnagar, Rohit ; Kapur, Pawan

Author_Institution

Council of Sci. & Ind. Res.-Central Sci. Instrum. Organ., Chandigarh, India

Volume

13

Issue

11

fYear

2013

fDate

Nov. 2013

Firstpage

4139

Lastpage

4140

Abstract

A long period fiber grating (LPFG) coated with a combination of cobalt chloride and gelatin is proposed and demonstrated for the monitoring of relative humidity (RH) levels. The thin overlay of the combination and its spectral properties with respect to different ambient humidity levels are observed. Field emission scanning electron microscope and atomic force microscope have provided detailed evidence of attachment of the amalgamation on LPFG surface using adapted coating methodology. The results show a significant shift in the resonance wavelength of the coated LPFG when the RH is varied from 35% to 90%, with a sensitivity of 0.18 nm/% RH and accuracy of 98.55%.

Keywords

atomic force microscopy; fibre optic sensors; humidity sensors; scanning electron microscopy; LPFG surface; adapted coating methodology; amalgamation; atomic force microscope; combination; field emission scanning electron microscope; gelatin/cobalt chloride coating; long period fiber grating humidity sensor; relative humidity levels; resonance wavelength; spectral properties; thin overlay; Coatings; Cobalt; Fiber gratings; Humidity; Optical fiber sensors; Probes; Sensitivity; Long period fiber grating; coating; humidity sensor;

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2013.2277914

Filename

6578106