Single-mode fibre coupler as refractometer sensor

Pramana

Mridul Buragohain²  Pabitra Nath1¹ 

[1] Department of Physics, Tezpur University, Napaam, Sonitpur 784 028, India$$;Department of Electronics and Communication Technology, Gauhati University, Guwahati 781 014, India$$

关键词: Fibre-optic sensor;    intensity modulation;    back-reflected signal;    refractometer.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

We report a simple, non-intrusive fibre-optic refractometer sensor for measuring the refractive index of liquid and optically transparent solid medium. Sensing principle of the proposed sensor is based on monitoring the back-reflected light signal through the second input port of a 2 × 1 single-mode fibre coupler when light signal from the output port is focussed at the interface of air and a liquid or solid medium and back-reflected exactly along the same path. Depending on the refractive index of the medium, the amount of back-reflected intensity would vary and in the present work we exploit this principle to measure the refractive index of an optically transparent medium. Variation of refractive index as small as 0.001 RIU can be measured with our proposed sensor.

【 授权许可】

Unknown