Theoretical analysis and experimental evaluation of D-type optical fiber sensor with a thin gold film

A D-type optical fiber sensor with a thin gold film is proposed. From the results of simulations, we can achieve the best sensitivity of the D-type optical fiber sensor by choosing suitable parameters, e.g., the thickness of the thin film layer of gold and the length of the sensor. Its maximum sensitivity can reach 8 × 10−5 refractive index unit. The sensor has some merits, e.g., small size, less costly, smaller sample volume, high sensitivity, easy measurement, and suitable for in vivo test, etc., the D-type optical fiber sensor is valuable for chemical, biological and biochemical sensing. And its feasibility is demonstrated.