Fiber Optic Pressure Sensor of 0–0.36 psi by Multimode Interference Technique

AbstractThis paper presents the design, development and tests made to a fiber optic pressure sensor using the multimodal interference methodology (MMI) thus, we propose an alternative sensor to the ones available which are limited by high robust environments where the use of them is a potential hazard (explosive gases, corrosion and even electromagnetic fields). The range of work for this sensor is 0 to 0.36 psi, the arrangement used is formed by a laser diode, a sensing element, an electronic amplifying circuit, a data acquisition board and a computer. The sensing element used is a SMS fiber optic structure (singlemode–multimode–singlemode, where a multimode fiber is embedded between two singlemode fibers) placed within the contact surface (diaphragm) made of a polymeric material; the body of the sensor was made of nylamid. The bending produced in the diaphragm by the pressure inside the body of the sensor generates changes in the transmitted power response carried inside the fiber