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Humidity Responsive Photonic Sensor based on a Carboxymethyl Cellulose Mechanical Actuator



Matthew R. Hartings, Kevin O. Douglass, Zeeshan Ahmed


We describe an intuitive and simple method for exploiting humidity driven volume changes in carboxymethyl cellulose (CMC) to fabricate a humidity responsive actuator on a glass fiber substrate. We optimize this platform to generate a photonic-based humidity sensor where CMC coated on a fiber optic containing a Fiber Bragg grating (FBG) actuates a mechanical strain in response to humidity changes. The humidity driven mechanical deformation of the FBG results in a large linear change in Bragg resonance over the humidity range of 5 %RH (relative humidity) to 40 %RH. The measurement uncertainty over this range is only ± 2 %RH.
Sensors and Actuators B-Chemical


humidity, photonics, FBG, moisture, cellulose
Created July 15, 2018, Updated April 6, 2018