FORMALDEHYDE CONCENTRATION MEASUREMENT BASED ON OPTICAL BUNDLE FIBER AND UV-VIS LIGHT SOURCE*

Abstract:

We have successfully demonstrated a new sensor based on an optical fiber bundle for measuring formaldehyde concen-tration. Our sensor was tested using two different methods based on displacement tuning and reflection measurement in conjunction with a UV light source. The sample was illuminated with the UV-visible laser (OSL 2 Thorlabs), and the power output of the backscattered radiation was found to decrease linearly with respect to the formaldehyde concentration. Our sensor exhibits excellent sensitivity, linearity, and stability as it was tested for formaldehyde concentrations ranging from 0% to 5%. The displacement tuning method exhibited the sensitivity of 0.031 μW/% with 91% linearity while the reflection scheme provided a a sensitivity of 2634.3 counts/% with 98% linearity. In addition, our sensor is non-contact, which means that the sample and probe are protected from damage and harm. These results demonstrate the potential of our fiber bundle sensor as a reliable tool for monitoring formaldehyde concentrations in food safety applications in the future.

Key words:Fiber sensor, Formaldehyde sensor, Shifting method, reflection method, UV Range