Fiber-Optic Salinity Sensor Using Fiber-Optic Displacement Measurement With Flat and Concave Mirror

Non‐touch detection of rhodamine B concentration in distilled water using fiber coupler based on displacement sensor

“…The development of refractive index and substance concentration sensor has been done with various methods and configurations. Reflection method using mirror (flat or concave) has been used to detect the refractive index of the liquid, calcium concentration, sodium chloride, glucose, rhodamine B, and magnesium using fiber bundle or fiber coupler as the sensor probe. The working mechanism of the refractive index and substance concentration sensor is based on displacement sensor, that is, by shifting the sensor probe against the mirror with the solution being made as a medium between sensor probe and mirror.…”

“…The detection mechanism is carried out through changes in light intensity guided in microbend or tapered fiber optic due to changes in the refractive index or the content of the solution on the side of microbend or tapered fiber optic. For the detection method of the sensor using reflection technique and side‐emitting, the working principle utilizes refraction, absorption, or refraction as well as absorption of light due to interaction with the solution. Another method has been developed based on surface plasmon resonance (SPR) using silver‐coated fiber optic and Nano composite of ZnO‐polypyrrol as a sensor probe, each capable of detecting the concentration of uric acid and manganese ions.…”

Touchless Mechanism to Detect Rhodamine B Concentration in Distilled Water Using Fiber Bundle

“…Side-emitting technique uses a microbend [7] and tapered fiber optic [8] as a sensor probe was successfully applied to detect the refractive index of chlorinated water and uric acid concentration. e method based on optical fiber displacement sensor was successfully used to detect the liquid refractive index [9], concentration of calcium [10], sodium chloride [11], glucose [12,13], rhodamine B [14], and magnesium ion [15]. In all mentioned methods, detection of changes in the refractive index or concentration of the solution is carried out through changes in light intensity due to the displacement of the sensor probe to the reflector.…”

Ag micro-spheres doped silica fiber used as a miniature refractive index sensor

“…The photonic crystal fiber, tapered fiber, fiber grating and fiber interferometer have been explored to sense the concentration change of NaCl solution [12][13][14][15][16]. The corresponding sensitivity have been obtained as high as 46.4 mV/RIU for the intensity modulation method [17] and ∼1400 nm/RIU for the wavelength modulation method [18].…”