When the humidity increases, the material absorbs water molecules, leading to an increase in refractive index. This change is detected by the optical fiber, allowing the sensor to measure humidity levels. The full range of applications include: (a) manufacturing (e. Accurate humidity measurement is essential to ensure product quality, prevent equipment damage, and maintain a healthy environment. Optical sensors have emerged as a. Owing to different environments and requirements, a wide variety of humidity-sensing technologies (e., humidity sensors or hygrometers) have been researched and developed in the literature, including optical/photonic/optoelectronic [1, 2, 3], quartz crystal microbalance (QCM) [4, 5], capacitive.