“…Sensors are very significant electronic circuit components; they make our daily lives easier, and they have an important role in personal and national security, environmental sensing, biochemical sensing, energy conservation, industrial manufacturing, and many sectors, such as agriculture, medicine, automotive, and space industry . There are various sensors, including optical sensors, chemical sensors, electrochemical sensors, optical chemical sensors, optical fiber sensors, fiber‐optic sensors, fiber‐optic chemical sensors, evanescent field absorption fiber sensors, fiber‐based refractive index (RI or n ) sensors, fiber‐optic RI sensors, luminescent sensors, evanescent wave sensors, ultraviolet sensors, speed sensors, humidity sensors, gas sensors, biosensors, magnetic field sensors, pressure sensors, temperature sensors, and vibration sensors …”