The Journal of Korean Institute of Electromagnetic Engineering and Science (한국전자파학회논문지)

The Korean Institute of Electromagnetic Engineering and Science (한국전자파학회)
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Terahertz Imaging Using Compact Continuous Wave Sub-Terahertz System

소형 CW Sub-THz 시스템을 이용한 테라헤르츠 이미징

  • Jang, Jin-Seok (Safety Metrology Center, Korea Research Institute of Standards and Science) ;
  • Kwon, Il-Bum (Safety Metrology Center, Korea Research Institute of Standards and Science) ;
  • Yoon, Dong-Jin (Safety Metrology Center, Korea Research Institute of Standards and Science) ;
  • Seo, Dae-Cheol (Safety Metrology Center, Korea Research Institute of Standards and Science)
  • 장진석 (한국표준과학연구원 안전측정센터) ;
  • 권일범 (한국표준과학연구원 안전측정센터) ;
  • 윤동진 (한국표준과학연구원 안전측정센터) ;
  • 서대철 (한국표준과학연구원 안전측정센터)
  • Published : 2010.04.30
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Abstract

This paper presented compact CW sub-THz imaging system using the terahertz transmitter(Tx) that generates 0.34 THz electromagnetic wave based on electronic device. Using 0.34 THz electromagnetic wave generated by Tx, we measured transmitting terahertz wave magnitude and phase information respectively with terahertz receiver(Rx) based on sub harmonic mixer. This paper measured and compared images of several samples to obtain better imaging results by changing time delay and step distance of scanning stage which affect image resolution. Also, through the imaging measurement of various samples, we were able to assure possibility of application of terahertz wave.

전기적인 장치를 기반으로 한 테라헤르츠 송신기(Terahertz Transmitter: Tx)를 이용하여 0.34 THz의 전자기파를 발생시키는 소형 CW sub-THz 이미징 시스템을 제시하였다. Tx에 의해 발생된 0.34 THz의 전자기파는 테라 헤르츠 수신기(Terahertz Receiver: Rx)를 이용하여 샘플의 진폭(magnitude)과 위상(phase) 정보를 각각 측정하였다. 이 논문에서는 보다 좋은 이미지 해상도를 얻기 위하여 데이터 수집 시 이미지의 분해능(resolution)에 영향을 미치는 주사 스테이지(scanning stage)의 시간 지연과 스텝 거리를 변수로 두어 다양한 샘플들을 주사하여 그 결과를 측정, 비교하였다. 또한 플라스틱, 종이, 나무 등 다양한 샘플들의 이미징 측정을 통해 테라헤르츠 파의 응용 가능성을 확인하였다.

Keywords

References

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