基于PDMS膜封装空芯光纤的级联双腔温度传感器

Cascaded Double-Cavity Temperature Sensor Based on Hollow Fibers Encapsulated by PDMS Membrane

提出并制备了一种基于聚二甲基硅氧烷(PDMS)膜封装空芯光纤的级联双腔温度传感器。该传感器由空气腔(FP1)和PDMS腔(FP2)级联而成,且PDMS腔长度远小于空气腔长度,从而使该传感器满足游标效应产生条件[FP1腔与复合腔FP3(由FP1和FP2组成)的光程接近]。当外界温度变化时,PDMS膜向两侧膨胀,导致FP1腔和FP3腔的干涉谱向相反的方向移动。实验结果表明,FP1腔和FP3腔干涉谱产生了游标效应,干涉谱包络明显;在50~60℃范围内,温度灵敏度达到1.32 nm/℃,该结果与理论分析结果相符。该传感器具有体积小、结构轻、灵敏度高、制备简单等优点,在化学、生物、医疗等领域具有潜在的应用价值。

A cascaded double-cavity temperature sensor based on hollow fibers encapsulated by polydimethylsiloxane(PDMS)membrane is proposed and prepared.The sensor consists of an air cavity(FP1)and a PDMS cavity(FP2)that are cascaded,and the PDMS cavity is much shorter than the air cavity so that the sensor can meet the condition of the Vernier effect[the optical path of FP1 is close to that of the composite cavity FP3(composed of FP1 and FP2)].When the external temperature changes,the PDMS membrane expand to both sides,resulting in the interference spectra of FP1 and FP3 move in the opposite direction.The experimental results show that the interference spectrum of FP1 and FP3 manifest the Vernier effect,and the envelope of the interference spectrum is obvious.The temperature sensitivity reaches 1.32 nm/℃in the range of 50--60℃,which is consistent with the theoretical analysis results.The proposed sensor,with the advantages of small size,light structure,high sensitivity,and simple preparation,has application potential in chemistry,biology,and medical treatment.