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Visualization of Khitan Scripts in Ancient Documents using Active Infrared Thermography

고문서 거란문자의 능동형 적외선 열영상 가시화

  • 김노유 (한국기술교육대학교 메카트로닉스공학부) ;
  • 정재영 (한국기술교육대학교 교양학부)
  • Received : 2022.01.04
  • Accepted : 2022.03.08
  • Published : 2022.03.31

Abstract

Unreadable Khitan scripts of ancient documents written by indian ink on parchment(sheepskin) are visualized by active infrared thermography without contacting and damaging the document which are deteriorated and aged presumably over many years. Sinusoidal infrared thermal wave using Halogen lamp is applied to the surface of the document in order to selectively magnify and record the thermal response of indian ink. The infrared image of the document captured in real time by infrared camera under the active external excitation shows the better sharpness and readability of Khitan characters than the optical image, from which many Khitan letters like ' ' and ' ' sounding as 'd' and 'ri' in English alphabet are detected and deciphered. It is concluded from the experiment that the active infrared thermography can be used as a promising method for digital reconstruction and preservation of ancient documents in the future.

양피지로 만들어진 고문서에 필사된 후 오랜 시간동안 부식되고 자연 훼손되어 해독하기 어려운 거란문자를 문서를 손상시키지 않으면서 비접촉방식으로 가시화하기 위해 능동형 적외선 열화상 기술을 개발하였다. 문서 표면에 할로겐 램프를 이용하여 광대역 적외선을 정현파 형태로 변조/입사시키면서 서체 부분과 기록용지 표면으로부터 차별적으로 방사되는 적외선을 영상화함으로서 훼손되어 잘 보이지 않는 고대 글자를 가시화 하였다. 능동형 적외선 영상으로부터 거란 문자로 추정되는 문자들을 기존의 광학영상이나 적외선 영상보다 명확하게 판독할 수 있었으며 그 결과로서 영어 알파벳의 'd' 음가를 가지는 거란문자인 ' '나 'ri' 발음의 거란문자인 ' '를 포함하여 다양한 거란문자를 확인할 수 있었다. 이로서 본 연구를 통해 개발된 능동형 적외선 기술이 향후 고문서 자료의 디지털 복원과 보존에 능동형 적외선 열화상기술이 효과적으로 활용될 수 있을 것으로 기대된다.

Keywords

Acknowledgement

본 연구는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원(NRF-2021M2E6A1084689)과 2021년도 한국기술교육대학교 교수교육연구진흥과제 지원에 의하여 수행되었으며 이에 감사드립니다.

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