Research Analysis Behavior Of Chemical Modified Mode-Filtered Light Optical Fiber Sensor

Chapter 1:This chapter describes the common types of fiber optic sensors, it describes the working principle of the spectral absorption optical fiber sensors, the fluorescence optical fiber sensor, the evanescent wave optical fiber sensors,the surface plasmon resonance fiber optic sensors and the mode-filter optical fiber sensors, and the mode-filter optical fiber sensors,were reviewed importantly in this paper.Chapter 2:Constructing the mode-filter optical fiber sucrose sensor use naked fiber and capillary.It measured a series of standard solutions of different concentrations of sucrose, Sucrose solution response range is 0-60% (w/w), the mode filter strength and solution concentration is the linear relationship, correlation coefficient R=0.9994. The sensor has good reproducibility and reversible, and has better the actual sample recoveries, it provides real-time, sucrose concentration online, fast and sensitive determination methods.Chapter 3:This chapter uses sol-gel technology coating pyrocatechol violet dye into the fiber surface and Inserting the modified fiber into the capillary to construct a new type of mode filter pH sensor. In the coating thickness for 5μm, flow rate for 1.11 mL/min conditions, the sensor has good response for pH. The response time is 168s, response range is 6～11, and in 6～9 have good linear relationship, correlation coefficient R is 0.9995. WhenΔpH≥0.2, it has good resolution. In addition, the sensor has good reproducibility, reversible and accuracy, some common metal ions almost have no interference for the sensor.Chapter 4:This chapter uses sol-gel technique with the preparation of phenol blue bromide fiber coating solution, and coat it on the fiber surface. Then inserting the coating fiber into the capillary to construct a new optical fiber pH sensors. In the following 0.99 mL/min conditions, The sensor has good response for pH, response time is 98s, the response range is 2～8. In 2-8 range, it is s-type response curve, correlation coefficient R=0.9990. The sensor has a good reproducibility and reversible, But the ion interference is more serious, The interference of Na+, K+ and NH4+ ions are especially serious.Chapter 5:This chapter makes sol-gel mixture for containing bromine cresol green and coat it on the fiber surface. Then inserting the coating fiber into capillary to construct a new optical fiber K+ sensors. In the following 1.11 mL/min conditions, The sensor has good response for K+, response time is 132s, the response range is 0.25-20.0 mmol/L, In this range, The K+ sensors to the standard solution in the response is curves changing, nonlinear equations is I= 2071.1- 505.5 Ln [K+] (mmol/L), correlation coefficient R=0.9988. The sensor also has good reproducibility and reversible, except Pb2+, some common ions to the sensor have a little impact.