• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1615-1618
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• 2007

Performances of LCDs are generally evaluated in terms of luminance and color versus viewing angle. In the present paper we show that this type of display can be favorably characterized in terms of polarization. We show that ELDIM EZContrast instrument can be used to measure the degree of polarization the light and the ellipticity and polarization direction of the polarized component. This measurement is made versus incidence angle between 0 and $88{\circ}$ and for all the azimuth angles. Important differences between the displays can be detected and related to their internal structures when luminance and color profiles are quite similar.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1033-1036
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• 2008

In this paper, we describe the development of the polarized-light stereoscopic monitoring system based on full HDTV. The system consists of the stereoscopic camera part, image processing device for the stereoscopic image recording and stereoscopic display. The developed stereoscopic imaging display system reduces eyestrain and viewer fatigue.

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.151-152
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• 2007

In this study, the optical porosity of $TiO_2$ films with helical structure deposited by glancing angle deposition (GLAD) were investigated. Helical films are of interest due to their ability to differentiate states of circularly polarized light. We designed and fabricated normal-incidence circular-polarization separator deposited by GLAD (Helical structure). The optical porosity of $TiO_2$ film deposited by helical method can be applied many optical coatings.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1281-1282
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• 2015

본 논문에서는 원편광 초고주파를 이용한 무전극 플라즈마 광원 기술과 광원의 특성을 논의한다. 특히 비회전 무전극 플라즈마 광원을 Solar Simulator용 광원으로 적용하여 그 특성을 설명한다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.48-48
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• 2004

• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.179-182
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• 2001

Photocyclizable poly(cinnam-4'-yl methyl methacrylate) derivatives bearing methoxy benzene (PMCMMA), anthracene (PACMMA), and coumarin (PCCMMA) have been synthesized via Heck type reaction. Three different types of polymers are photoreactable usin g linearly polarized UV light and applicable as liquid crystal alignment layer. Anthracence and coumarin containing polymers (PACMMA, PCCMMA) have better thermal stability than PMCMMA. This observation may be attributed to the glass transition temperature elevation due to the bulky size and another photocrosslinking site provided by anthracene or coumarin group.

• Journal of Multimedia Information System
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• v.7 no.4
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• pp.239-248
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• 2020

The performance of the facial recognition system is determined by many technical factors. Further, most of the technical factors have been realized or are still in continued research. The recognition rate has a great influence on performance not only by technical factors but also by other factors. However, researchers are trying to improve the recognition rate by focusing only on technical factors. The mechanism of recognizing is to compare a face image obtained by photography to an already stored face image and determine the score of the similarity. However, if the photographed image is damaged by external light, even a system with a good algorithm will fail to recognize it. Therefore, it is important to prevent the disturbance of light entering from the outside, so it should be blocked, but the camera will not work without light. Thus, it is proposed that a method to secure the external light but block the disturbance of light that affects photography. A method of blocking disturbance light is to use a polarization filter. There are three polarization methods: circular polarization, linear polarization, and elliptical polarization. In this paper, an experiment was performed to overcome disturbance of light using only a circularly polarized filter. In addition, a lighting system that reproduces disturbance light was provided for the experiment, and light of varying intensities and angles was installed to affect the face recognition camera. As a result of actual application, it was determined that a very improved recognition performance in various disturbance light environments.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.172-172
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• 2010

In the area of optoelectronic devices based on GaN and related ternary compounds, the two-dimensional system like as quantum wells (QWs) has been investigated as an effective structure for improving the light-emitting efficiency. Generally, the quantum well active regions in III-nitride light-emitting diodes grown on conventional c-plane sapphire substrates have critical problems given by the quantum confined Stark effect (QCSE) due to the effects of strong piezoelectric and spontaneous polarizations. However, the QWs grown on nonpolar templates are free from the QCSE since the polar-axis lies within the growth plane of the template. Also the unique characteristic of linear polarized light emission from nonpolar QW structures is attracting attentions because it is proper to the application of back-light units of liquid crystal display. In this study, we characterized optical properties of the a-plane InGaN/GaN QW structures by temperature-dependent photoluminescence (TDPL) measurements. From the photoluminescence (PL) spectrum measured at 300 K, green emission centered at 520 nm was observed for the QW region. Since indium incorporation on nonpolar QWs is lower than that on c-plane, this high indium-doping on a-plane InGaN QWs is not common. Therefore, the effect of high indium composition on optical properties in a-plane InGaN QWs will be extensively studied.

• Current Optics and Photonics
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• v.7 no.2
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• pp.136-146
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• 2023

Based on calculations using the macroscopic Maxwell's equations with mesoscopic boundary conditions, light absorption by a layered metal-insulator-metal (MIM) metamaterial system embedded in three different environments is investigated. Increasing the top metal thickness shifts the broad absorption band to lower dielectric-constant regions and longer wavelengths, for either TM or TE waves. Boosting the dielectric-layer thickness redshifts the broadband absorption to regions of larger dielectric constant. In air, for the dielectric-constant range of 0.86-3.40, the absorption of the system exceeds 98% across 680-1,033 nm. In seawater with optimized dielectric constant, ≥94% light absorption over 400-1,200 nm can be achieved; particularly in the wavelength range of 480-960 nm and dielectric-constant range of 0.82-3.50, the absorption is greater than 98%. In an environment with even higher refractive index (1.74), ≥98% light absorption over 400-1,200 nm can be achieved, giving better performance. The influence of angle of incidence on light absorption of the MIM system is also analyzed, and the angle tolerance for ≥90% broadband absorption of a TM wave is up to 40° in an environment with large refractive index. While the incident-angle dependence of the absorption of a TE wave is nearly the same for different circumstances, the situation is different for a TM wave.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.4
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• pp.253-258
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• 2010

Until now, evaluating the efficacy of brightening mainly depends on total reflective light measurement. For example, SHV (Saturation, Hue, Value), $L^*$ $a^*$ $b^*$ (CIELAB color space system) color space system was used and lightness and saturation changes were chosen as major parameters for evaluating brightening effect. However, those parameters were calculated from total reflective light on the skin and it is hard to evaluate perceptive efficacy such as luminescence, and glossy. In this research, we applied new method for estimating change of luminescence of skin by using 'Lumiscan' which uses polarized light for detecting surface and inside reflective light independently. We also tested 15 different parameters for finding correlations between luminescence and those parameters. As a results, our 2 different brightening products showed 5 ~ 9 % increase of luminescence at 4 and 8 weeks. And we also found that skin roughness (-28 %), melanin index (-17 %), redness (-7 %), hydration (15 %), and lightness (6 %) were related to luminescence of skin.