Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Terahertz Time-Domain Spectroscopy and Imaging using Compact Fiber-coupled Terahertz Modules

초소형의 광섬유 결합형 테라헤르츠 모듈을 이용한 시간영역에서의 분광 및 이미징

  • 윤영종 (한국전자통신연구원 THz포토닉스창의연구센터) ;
  • 김남제 (한국전자통신연구원 THz포토닉스창의연구센터) ;
  • 류한철 (삼육대학교 메카트로닉스학과) ;
  • 문기원 (한국전자통신연구원 THz포토닉스창의연구센터) ;
  • 신준환 (한국전자통신연구원 THz포토닉스창의연구센터) ;
  • 한상필 (한국전자통신연구원 THz포토닉스창의연구센터) ;
  • 박경현 (한국전자통신연구원 THz포토닉스창의연구센터)
  • Received : 2014.02.03
  • Accepted : 2014.02.24
  • Published : 2014.04.25
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Abstract

We have demonstrated a terahertz (THz) time-domain spectroscopy and imaging system using compact fiber-coupled THz modules. Using this THz spectroscopy system we have measured the absorption spectrum of water vapor in free space over 3 THz, as well as the refractive indices of various substrates such as Si, $Al_2O_3$, and GaAs using the transfer-function method. Through the THz imaging system we have observed a high-quality THz image of a medical knife and metal clip sample, with a resolution of $192{\times}89$ pixels using a step size of 250 ${\mu}m$.

본 논문에서는 초소형의 광섬유 결합형 테라헤르츠 모듈을 이용하여 테라헤르츠 시간영역 분광 및 영상 시스템을 구성하였다. 구성된 THz 분광 시스템을 이용하여 3 THz 이상의 자유공간에 분포되어 있는 수분의 고유 흡수 스펙트럼을 관측하였고 테라헤르츠 대역에서의 Si, $Al_2O_3$, GaAs기판에 대한 굴절률을 측정하였으며 측정을 위해 다중 반사를 고려한 전달 함수를 이용한 굴절률 측정 방법을 이용하였다. 또한, 테라헤르츠 영상 시스템을 이용하여 의료용 칼과 클립을 측정하여 250 ${\mu}m$ 간격으로 $192{\times}89$ 픽셀의 영상을 얻었다.

Keywords

References

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