• 정보저장시스템학회논문집
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• 제2권4호
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• pp.219-223
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• 2006

Near field recording(NFR) technology has been considered as a strong candidate to surpass the far-field diffraction limit imposed by the nature of light in present optical disk drives such as CD, DVD, and BD(Blu-ray Disk). In this paper, we suggest novel inside near-field dual layer recording concept using elliptic shape solid immersion lens(ESIL).

• 정보저장시스템학회논문집
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• 제4권1호
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• pp.1-5
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• 2008

Super-resolution near-field structure (super-RENS) technology and solid immersion lens (SIL) based near-field (NF) technology have been expected as promising approaches to increase data capacity or areal density of optical disc. Super-RENS technology has been studied until now using mainly numerical aperture (NA) of 0.85 far-field optical system and possibility of tangential data density increment have been presented. NF technology has been studied with NA over 1 and presented demonstration of removable performance. To achieve much higher density, approach to increase NA of super-RENS by NF technology (Near-Field Super-Resolution, NFSR) can be a candidate and we think this technology would be advantageous compared to wavelength reduction or much higher NA increment of NF technology or much smaller effective optical spot size reduction of far-field super-resolution technology. In this paper we present readout result of ROM media having monotone pits using NF optical system with wavelength of 405nm and NA of 1.84 surface type SIL. GeSbTe material was used for super resolution active layer and pit length is 37.5nm which is shorter than resolution limit 55nm. We present the feasibility of NFSR technology by confirming the CNR threshold according to readout power (Pr) and CNR 33dB over threshold Pr.

• 정보저장시스템학회논문집
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• 제3권1호
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• pp.1-4
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• 2007

A high density optical data storage device has been required for many years. In the field of the optical data storage, a near-field recording (NFR) technology is considered as a next generation one for achieving the high data density. Due to an evanescent wave effect occurred under 100nm distance which is the excessively small distance between the SIL and the disc, the most significant and difficult problem in this technology is to maintain a gap between a solid immersion lens (SIL) and a disc. Also, maintaining the gap under at least 50nm is required in the NFR gap servo system to use the evanescent wave effect efficiently. There are some institutes that have shown the novel gap servo control. In general, they use a mode switching servo method which consists of approach, hand-over and gap control mode. However there is a critical problem such as an overshoot at the tuning point from the approach mode to the hand-over mode, which may cause a collision between the SIL and the disc. In this paper, we show our NFR system and an improved gap servo system using an exponential function as the approach mode which can reduce the overshoot.

• 정보저장시스템학회논문집
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• 제6권2호
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• pp.79-82
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• 2010

In optical imaging systems, such as microscopes, high resolution exposure systems, and optical storage devices, higher optical resolution is a requirement. One of the promising technologies that is able to satisfy this requirement with relatively simple construction and reliable performance are, solid immersion lens (SIL)-based near-field (NF) optical systems. High NA optical systems using annular apertures have been investigated as one solution to achieve higher resolutions and an extended focal depth. By applying an optimized annular aperture to convention SIL optical head resolution can be increased by approximately 20%. This novel SIL-based near-field optics will be verified through experiments such as measuring focused beam spot profiles and observing the topology of a measurement sample. The studied SIL-based near-field optics can be applicable to not only next generation optical storage device but also high resolution microscopy and pattering technologies.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2018년도 제58차 하계학술대회논문집 26권2호
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• pp.189-190
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• 2018

최근에는 여행에 대한 각종 정보가 많이 공유되는 추세이다. 최근 사람들은 소셜 네트워크 서비스를 이용 중이거나 웹 서핑을 하는 도중에 기억하고 싶어 하는 여행지를 단순히 캡처 해놓거나 메모장에 기록해둔다. 이러한 방법은 시간이 지나 많은 데이터가 쌓이면 관리하기 어렵다는 문제가 존재한다. 본 논문에서는 사용자의 편리를 고려하여 사진의 텍스트를 광학식 문자 판독을 활용하여 출력하고 게시 글 형태로 저장할 수 있게 개발하였다. 명소의 위치 또한 자동완성 위치 검색 라이브러리를 통하여 편리 저장이 가능하다. 위치 데이터를 통해 향후 사용자가 근접하고 있는 여행지 또한 제공해줄 수 있도록 구현하였다. 이를 위하여 웹을 통해서 이용할 수도 있으며 실시간 검색과 알림 이벤트를 위해 웹 주소 입력 없이도 앱을 실행할 수 있는 프로그래시브웹 앱을 구현하였다.