Design Model of Intensity Modulation Type Displacement sensor Using Step-index Multimode Optical Fiber

스텝 인덱스 멀티모드 광섬유를 이용한 광강도 변조방식 변위센서 설계모델 연구

  • Shin, Woo-Cheol (Intelligent Machine Systems Center, Korea Institute of Machinery and Materials) ;
  • Hong, Jun-Hee (Department of Mechanical Engineering, BK21 Mechatronics Group at Chungnam National University)
  • 신우철 (한국기계연구원 지능기계연구센터) ;
  • 홍준희 (충남대학교 기계공학과 BK21 메카트로닉스 사업단)
  • Published : 2006.12.25


An optical fiber displacement sensor has the advantages of relatively simplicity, cheap, small probe size and immunity against environmental perturbation. The working principle of the sensor is based on the intensity modulation that is detection light intensity reflecting from the surface being measured. This paper presents the mathematical model of displacement measurement mechanism of this sensor type. The theoretical and experimental data are compared to verify the model in describing the realistic approach to sensor design. Finally, the analysis results show that displacement response characteristics such as sensitivity, measuring range are easily modified by principal design parameters such as magnitude of optical Power, diameter of optical fiber core and distance between transmitting fiber and receiving fiber.


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