• 제목/요약/키워드: light sensitivity

검색결과 622건 처리시간 0.028초

유기 비선형 광학 재료를 이용한 플라스틱 광섬유 제작 및 특성 (Characteristics and fabrication of POF using organic nonlinear optical materials)

  • 김응수;강신원
    • 센서학회지
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    • 제15권4호
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    • pp.297-301
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    • 2006
  • We have fabricated a multi-mode nonlinear plastic optical fiber (POF) using organic nonlinear optical materials and demonstrated the propagation of light. The refractive indices of core and cladding are 1.5240 and 1.5172. We made a POF preform by rod-in tube method. The core diameter of the fabricated POF is about $30{\mu}m$. We evaluated the temperature characteristics of POF. The sensitivity is $0.345{\;}mW/^{\circ}C$ and the linearity of sensor was good.

Trihydric Phenol계 Photoresist의 합성과 그 감광 특성 (Synthesis and Photocharacteristics of Trihydric Phenol Photoresist)

  • 홍의석;고재용;박홍수
    • 한국응용과학기술학회지
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    • 제13권1호
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    • pp.47-54
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    • 1996
  • Cinnamoyl ester(PGEFC) of poly(phloroglucinol-formaldehyde) glycidyl ether which has photosensitive functional group was prepared to apply to photoresist. Photosensitivity of PGEFC was estimated by the solubility difference in organic solvent before and after exposure to light. The yield of residual film was calculated by immersing the sample-coated quartz plates in the solvent which was used in coating. The yield of the residual film which was closely related to the sensitivity of the film, was affected by the degree of polymerization of the backbone resin, sensitizers and their concentration. The sensitivity was depended upon the degree of polymerization. Most of effective sensitizer for PGEFC among the sensitizers was 2, 6-dichloro-4-nitroaniline.

CMOS binary image sensor with high-sensitivity metal-oxide semiconductor field-effect transistor-type photodetector for high-speed imaging

  • Jang, Juneyoung;Heo, Wonbin;Kong, Jaesung;Kim, Young-Mo;Shin, Jang-Kyoo
    • 센서학회지
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    • 제30권5호
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    • pp.295-299
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    • 2021
  • In this study, we present a complementary metal-oxide-semiconductor (CMOS) binary image sensor. It can shoot an object rotating at a high-speed by using a gate/body-tied (GBT) p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET)-type photodetector. The GBT PMOSFET-type photodetector amplifies the photocurrent generated by light. Therefore, it is more sensitive than a standard N+/P-substrate photodetector. A binary operation is installed in a GBT PMOSFET-type photodetector with high-sensitivity characteristics, and the high-speed operation is verified by the output image. The binary operations circuit comprise a comparator and memory of 1- bit. Thus, the binary CMOS image sensor does not require an additional analog-to-digital converter. The binary CMOS image sensor is manufactured using a standard CMOS process, and its high- speed operation is verified experimentally.

Reliability analysis on fatigue Strength for Certification of Aircraft Composite Structures

  • Choi, Cheong Ho;Lee, Doo Jin;Jo, Jae Hyun;Bae, Sung Hwan;Lee, Myung Jik;Lee, Jong Ho
    • 항공우주시스템공학회지
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    • 제15권2호
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    • pp.16-25
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    • 2021
  • Reliability of fatigue strength on Aircraft Composites(GFRP) Structures was assessed in this paper. Fatigue strength of GFRP was used through the existing fatigue test data with Monte Carlo method. The Sa-Nf curve of composites fatigue strength was assumed as normal distribution and reliability was analyzed using SSIT model. Fatigue stress was designed IAW ASTM F3114-15 with special safety factor of Ssf=1.2~2.0. Reliability was calculated by analytic method and FORM. Sensitivity for the effect of mean and standard deviation of fatigue strength as well as fatigue stability was evaluated. This result can be usefully applied to reliability and fatigue design for composite structures of light weight aircraft.

광중합기를 이용한 광학적 치아우식활성도 검사법 (DEVELOPMENT OF OPTICAL CARIES ACTIVITY TEST USING DENTAL CURING LIGHT)

  • 이난영;김미라;오유향;이창섭;이상호
    • 대한소아치과학회지
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    • 제31권4호
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    • pp.671-679
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    • 2004
  • 레이저와 플라스마 광, 할로겐 광 중합기를 이용하여 각 개인의 우식 활성토를 측정할 수 있는지를 규명하기 위해 7-8세 아동 45명을 대상으로 치아의 순면과 협면에 각 광원을 조사하고 특수 필터를 사용하여 초기 치아우식증으로 판별된 치아의 개수를 측정하여 기존의 우식활성도 측정방법인 dDfFtT rate와 mutans streptococci 측정법, Lactobacilli 측정법과 비교, 평가하고 그 특이도, 민감도, 예측력을 평가하였다. 1. 아르곤 레이저, 플라스마 광, 할로겐 광 조사시 육안검사시 보다 유의하게 많은 초기우식 병소가 관찰되었다(p<0.05). 2. 아르곤 레이저, 플라스마 광, 할로겐 광을 이용한 우식활성도 측정법은 dDfFtT rate와 양의 상관관계 (${\gamma}=0.42,\;0.41,\;0.39$)를 보였다(p<0.01). 3. 기존의 우식활성도 측정방법을 기준으로 하여 평가한 결과 특이도와 민감도, 예측력은 모두 레이저가 가장 높았으며 플라스마 광, 할로겐 광 순으로 나타났다. 이상의 결과를 종합하여 볼 때 아르곤 레이저와 플라스마 광, 할로겐 광을 이용한 형광법은 모두 양호한 진단학적 지표를 보여줌으로써 향후 광학적 우식활성검사법으로 활용 가능성이 높을 것으로 사료된다.

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광음향효과에 의한 화합물 반도체의 물성연구 (A Study on the Physical Properties of Compound Semiconducts by Photoacoustic Spectroscopy)

  • 윤화중
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1984년도 추계학술발표회 논문집
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    • pp.27-32
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    • 1984
  • When chopped light inpinges on some condenced matters such as HgS, HgI2 and GaSe semiconductors, in an enclosed cell, the acoustic signals are produced within the cell. These acoustic signals were detected by using a gas-phase microphone in order to investigate the physical properties of the samples. In order to carry out investigation, PA-cell was first designed and made so as to produce higher sensitivity to acoustic signals. Second, an analysis of the photoacoustic spectrum of the various compounds was carried out to obtain the intensity of the PA-signal in terms of light wavelength and to calculate the energy band gaps occuring according to energy transitions. The agreement between the results obtained by this conventional PAS technique and the results obtained by the optical spectrum method was good. In additional analysis conducted on the basis of the R-G theory and the Sze theory are capable of determining the characteristics of energy transition of semiconductors.

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21세기 업무공간의 감성디자인 적용에 관한 연구 (A Study on Application of the Emotion Design to Office Space in 21st)

  • 한지연;신홍경
    • 한국실내디자인학회논문집
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    • 제16권2호
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    • pp.139-146
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    • 2007
  • This study is tended to analyze the characteristics of the emotional office environment so that digital technologies may adapt to the rapidly progressing social structure in a flexible way, investigate the interior composition of the changing office space and the element and direction of design and then present the indoor environment appropriate to it with the desirable alternative to the emotional office. The recognition of emotionality becomes so important that it is called 'emotional society'. Emotional design, which is mostly concern about user's consensus & experiences and in the space, is appeared on office. Emotional design is understanded from a interactive point of view, human and interior-space. The important factors of this study are light, color, immateriality and fun sensitivity The purpose of this study is to examine the emotional design by analysis of multifarious spaces. Office space Is designed emotional and experienced in the future.

Effects of some factors on the thermal-dissipation characteristics of high-power LED packages

  • Ji, Peng Fei;Moon, Cheol-Hee
    • Journal of Information Display
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    • 제13권1호
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    • pp.1-6
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    • 2012
  • Decreasing the thermal resistance is the critical issue for high-brightness light-emitting diodes. In this paper, the effects of some design factors, such as chip size (24 and 35 mil), substrate material (AlN and high-temperature co-fired ceramic), and die-attach material (Ag epoxy and PbSn solder), on the thermal-dissipation characteristics were investigated. Using the thermal transient method, the temperature sensitivity parameter, $R_{th}$ (thermal resistance), and junction temperature were estimated. The 35-mil chip showed better thermal dissipation, leading to lower thermal resistance and lower junction temperature, owing to its smaller heat source density compared with that of the 24-mil chip. By adopting an AlN substrate and a PbSn solder, which have higher thermal conductivity, the thermal resistance of the 24-mil chip can be decreased and can be made the same as that of the 35-mil chip.

레이저 스페클간섭법에 있어서 스페클크기와 측정 한계에 관한 연구 (A study on speckle size and measurable limitations in laser speckle interferometry method)

  • 윤성운
    • 한국생산제조학회지
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    • 제5권1호
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    • pp.33-42
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    • 1996
  • The high coherence of laser beam has made it possible to observe interference effects even in the light scattered from rough surfaces. That's why, when object with a scattering surface is illuminated with laser light, we do see a speckled appearance due to random interference. This sort of unique property of laser speckle has bruht into existence the new noncontaciting techniques such as speckle metrology method of measuring deformation, displacement, and vibration etc of objects with high optical sensitivity. The measurable range of speckle metrology especially used to measure in -plane information, however, is limited by some factors, the so-called strain, rotation tilt of surface and out of displacement perpendicular to the plane of analysis This restrictions severly limits the measurable range of speckle metrology by causing the decorrelation of speckle patterns. It is the purpose of this paper to give a survey on the measurable limitation of speckle photography method that is one of speckle metrology. Namely we will discuss the mutual relationships and problems of each limitations adding the restriction on the largest and smallest displacement measurable with speckle methods.

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장력제어 기법을 이용한 Hybrid형 케이블 구조물의 비선형 시공해석 (Nonlinear Analysis of Hybrid-Typed Cable Structures by Stress Control)

  • 정을석;김승덕
    • 한국공간정보시스템학회:학술대회논문집
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    • 한국공간정보시스템학회 2004년도 춘계 학술발표회 논문집 제1권1호(통권1호)
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    • pp.123-130
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    • 2004
  • The recent large-spatial structures are frequently made from light-weight structural system and it has a good mechanical efficiency and uses new materials. The large space is made by light-weight structural system using tension members mainly, and generally it is called a soft structure. The cable dome structures which are a soft structures are very flexible, the stresses and nodal coordinates of other members are changed when we control the stress of one member. Therefore, we have to do two kind of works for effective and accurate construction of the cable dome structures. The first work is making a working scenario to complete the final objective form and the second is revising constructional errors occurred in process of the actual works. These works are called constructional analysis. At this time, we have to consider geometric nonlinearity to reflect the sensitivity by the initial stresses of cable dome structures, and constructional analysis comes down to a nonlinear problem after all. In this study, we try to approach the constructional analysis of the cable dome structures using the numerical method, and then verify it.

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