Fiber-optic sensor for humidity

Area of Science:

• Optoelectronics
• Chemical Sensing
• Materials Science

Background:

• Traditional humidity sensors face limitations such as susceptibility to electromagnetic interference and bulkiness.
• There is a need for miniaturized, robust sensors for environmental monitoring and industrial applications.

Purpose of the Study:

• To develop and describe a novel fiber-optic humidity sensor.
• To leverage thin-film interferometry for sensitive and selective water vapor detection.

Main Methods:

• Fabrication of a porous thin-film interferometer at the tip of an optical fiber.
• Utilizing the reversible sorption of ambient water vapor by the thin film.
• Monitoring changes in the refractive index and reflectivity of the interferometer due to water sorption.
• Detecting humidity through modulation of the reflected light intensity.

Main Results:

• The fiber-optic sensor demonstrated reversible detection of ambient humidity.
• The sensor showed high sensitivity to water vapor through changes in reflected light intensity.
• The device exhibited robustness against electromagnetic interference and aggressive chemicals.

Conclusions:

• The developed fiber-optic humidity sensor is a promising technology for various applications.
• Its small size, sensitivity, and resistance to interference make it suitable for miniaturized sensing systems.
• This sensor offers a novel approach to optical humidity sensing with significant advantages over conventional methods.