利用塑料光纤作为传感和传光器件,以高亮度经正弦信号调制的蓝光LED为光源,基于倏逝波吸收原理进行葡萄糖浓度传感。实验研究了U形、双锥形、螺旋形传感头对不同质量浓度葡萄糖溶液的传感特性,实验结果为螺旋形传感头的灵敏度最高。螺旋形传感头的透射光功率与葡萄糖质量浓度之间呈线性关系,线性系数为0.986,系统的灵敏度为0.1μg/mL。实验还对螺旋形传感头在质量浓度分别为0mg/100mL和25mg/100mL葡萄糖溶液中透射光功率的重复性进行了测试,在5个循环内实验结果具有重复性。
Glucose concentration is detected by using evanescent absorption method. Plastic optical fiber is used as sensor head and light transmit element. A high brightness blue LED modulated with sine signal is used as excitation source with spectrum centered at 470 nm. The sensitivity of the system under different shaped sensor heads (U- shaped, biconical-shaped, spiral-shaped) is measured, and the spiral-shaped sensor head shows the highest sensitivity to glucose. The relationship between the spiral-shaped output light power and glucose concentration is linearly and the linear coefficient is 0. 986. The sensitivity of the sensor head is 0. 1 μg/mL reversibility when the sensor is tested by alternately cycling between 0 mg/100 mL solution in five cycles. The system shows excellent and 25 mg/100 mL glucose