• Title/Summary/Keyword: optics

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The Ingredients of Mascara Causing Effects on the Eyes (눈에 영향을 미칠 수 있는 마스카라의 성분)

  • Jang, Sun;Kho, Young Lim;Kim, Hyojin;Kang, Bonghoon;Lee, Eun-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.4
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    • pp.83-87
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    • 2009
  • Purpose: This study was performed to detect various chemicals such as metal elements and volatile organic compounds which contained in mascara and we analyzed 5 sorts of mascaras frequently used by people. Methods: We purchased five sorts of mascaras commercially available and analyzed for detecting metal elements and volatile organic ingredients. Results: We found somewhat high concentration of aluminum and manganese and several organic compounds in some samples. Conclusions: The results suggest that mascara has metal elements and organic compounds which can influence to eye.

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Variation of Magnetoresistance of rotation of Iron thin Film (철박막회전에 따른 자기저항의 변화)

  • Yang, Ki-Won;Son, Jeong-Sik;Kwak, Ho-Weon;Park, Sang-Chul
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.2
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    • pp.13-17
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    • 2007
  • Magnetoresistance(MR) in ferromagnetic thin film to make thermal evaporating method in various angle configurations were observed. The degree of transition from positive magnetoresistance to negative magnetoresistance is observed to 34 degree in anisotropy magnetoresistance experiment. In the angle configuration such that the film sample was placed perpendicular to the magnetic field, the difference of FDMP and degree of transition in iron and nickel films is observed due to the fundamental difference of magnetic easy axis.

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Development and Characterization of a 400-W Slab-type Nd:YAG Gain Module

  • Cha, Yong-Ho;Lee, Sungman;Lim, Gwon;Baik, Sung-Hoon;Kwon, Sung-Ok;Cha, Byung-Heon;Lee, Jung-Hwan;Kang, Eung-Cheol
    • Journal of the Optical Society of Korea
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    • v.16 no.1
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    • pp.53-56
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    • 2012
  • We have developed a slab-type Nd:YAG gain module based on the techniques of conduction cooling and end pumping. The Nd:YAG slab is end-capped on both ends by undoped pure YAG and is pumped through the end-caps by stacked arrays of laser diode bars. The slab's surfaces of total internal reflection are in contact on both sides with microchannel cooling blocks which are cooled by water circulation. The power oscillator based on the gain module generates more than 400 W at 1-kW pumping with a slope efficiency of 55%. The small-signal gain of the gain module is 10 in a single zig-zag pass, and the amplified beam shows a near diffraction-limited beam quality.

Efficient Single-Pass Optical Parametric Generation and Amplification using a Periodically Poled Stoichiometric Lithium Tantalate

  • Yu, Nan-Ei;Lee, Yong-Hoon;Lee, Yeung-Lak;Jung, Chang-Soo;Ko, Do-Kyeong;Lee, Jong-Min
    • Journal of the Optical Society of Korea
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    • v.11 no.4
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    • pp.192-195
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    • 2007
  • A high-conversion efficiency, nanosecond pulsed optical parametric generation and amplification with repetition rate of 20 kHz based on a periodically poled MgO-doped stoichiometric lithium tantalate was presented. Pumped by a Q-switched $Nd:YVO_4$ laser at 1064 nm with a pumping power of 4.8W, the generated output power was 1.6W for the signal and idler waves, achieving a slope efficiency of 50%. Using a seed source at signal wave the amplified signal output-pulse energy reached $65{\mu}J$. The obtained maximum gain was 72.4 dB.

Lenticular Lens Array without Cross-Talk (3차원영상의 입체감 향상을 위해 Cross-Talk을 최소화한 렌티큘러 렌즈)

  • Kim, Tae-Kyoung;Kim, Min-Jae;Hwang, Yeon;Cha, Du-Hwan;Kim, Hye-Jeong;Kim, Jeong-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.179-179
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    • 2010
  • 본 연구에서는 무안경식 3 차원 입체영상 기술에 쓰이는 렌티큘러 렌즈의 제작공정 중 오차(Error)로 작용할 수 있는 몇 가지 변수를 가정하였고 이러한 변수의 오차에 의해 좌우되는 가장 중요한 성능인자인 광학적 상호간섭 (Cross-Talk)을 최소화하도록 연구를 수행하였다. 이를 위해서 초정밀절삭가공과 UV경화법을 사용하였고 광학적 상호간섭 (Cross-Talk)에 가장 큰 영향을 주는 피치공차 (Allowance)를 ${\pm}0.5{\mu}m$내로 줄여서 3차원 입체감을 향상시킬 수 있음을 확인하였다.

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Error-immune Algorithm for Absolute Testing of Rotationally Asymmetric Surface Deviation

  • Zhang, Yanwei;Su, Dongqi;Li, Le;Sui, Yongxin;Yang, Huaijiang
    • Journal of the Optical Society of Korea
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    • v.18 no.4
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    • pp.335-340
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    • 2014
  • Based on Zernike polynomial fitting, we propose an algorithm believed to be new for interferometric measurements of rotationally asymmetric surface deviation of optics. This method tests and calculates each angular surface by choosing specified rotation angles with lowest error. The entire figure can be obtained by superimposing these sub-surfaces. Simulation and experiment studies for verifying the proposed algorithm are presented. The results show that the accuracy of the proposed method is higher than single-rotation algorithm and almost comparable to the rotation-averaging algorithm with fewer rotation measurements. The new algorithm can achieve a balance between the efficiency and accuracy.

Study on Clinical Assessment and Reliability Analysis of Measurement with Diverse Autorefractors (검사기기에 따른 굴절력 측정의 임상적 평가 및 신뢰도에 관한 연구)

  • Kim, Tae-Hun;Kwon, Young-Seok;Ye, Ki-Hun;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.4
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    • pp.293-298
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    • 2006
  • For this study, Clinical evaluation of the diverse Autorefractors was performed to examine validity and repeatability compared with subjective refraction. Measurements of refractive error were performed on 212 eyes of 106 subjects subjectivly noncycloplegic. Intersession repeatability of the Autorefractors were also assessed on all 106 subjects together with intersession repeatability on 7 to 14 days intervals. Spherical powers of subjective refraction and autorefractions by Autorefractors were analyzed by paired T-test.

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A Study on Thermal Deformation Compensation in the Molding of Aspheric Glass Lenses (비구면 유리렌즈 열변형 보정에 관한 연구)

  • Lee, Dong-Kil;Kim, Hyun-Uk;Cha, Du-Hwan;Lee, Hak-Suk;Kim, Hye-Jeong;Kim, Jeong-Ho
    • Journal of the Korean Society for Precision Engineering
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    • v.27 no.5
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    • pp.22-26
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    • 2010
  • Recently, due to the tremendous growth of media technology, demands of the aspheric glass lens which is a high-performance and miniaturized increase gradually. Generally, the aspheric glass lens is manufactured by Glass Molding Press (GMP) method using tungsten carbide (WC) mold core. In this study, the thermal deformation which was occurred by GMP process was analyzed and applied it to compensate the aspheric glass lens. The compensated lens was satisfied that can be applied to the actual specifications.

Football match intelligent editing system based on deep learning

  • Wang, Bin;Shen, Wei;Chen, FanSheng;Zeng, Dan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.10
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    • pp.5130-5143
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    • 2019
  • Football (soccer) is one of the most popular sports in the world. A huge number of people watch live football matches by TV or Internet. A football match takes 90 minutes, but viewers may only want to watch a few highlights to save their time. As far as we know, there is no such a product that can be put into use to achieve intelligent highlight extraction from live football matches. In this paper, we propose an intelligent editing system for live football matches. Our system can automatically extract a series of highlights, such as goal, shoot, corner kick, red yellow card and the appearance of star players, from the live stream of a football match. Our system has been integrated into live streaming platforms during the 2018 FIFA World Cup and performed fairly well.

Clinical Study on Accommodation Using Subjective Test (자각적 검사를 이용한 조절력에 관한 임상적 연구)

  • Jung, Mi-Boon;Lee, Ki-Seok;Kim, Tae-Hun;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.2
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    • pp.137-141
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    • 2006
  • We have studied on the accommodation of people for 10~60ages at Honam residents and compared with the already known accommodation from age. Using Push-up method, we obtained results that average accommodation of each cases were 10ages 9.88D, 20ages 8.65D, 30ages 6.92D, 40ages 5.05D, 50ages 4.29D, 60ages 4.63D. Accommodation was on the decreased in increasing the ages but showed the very high accommodation in 50, 60ages on this study. We judged we should consider a accommodation research of other districts and near addition test.

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