• Journal of the Optical Society of Korea
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• 제13권1호
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• pp.75-79
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• 2009

A four beam interference optical system for laser micro structuring using a pulse laser was demonstrated. The four beam interference optical system using a pulse laser(picosecond laser) can fabricate micro structure on mold material(NAK80) directly. Micro structure on the polymer can be reproduced economically by injection molding of the micro structure on the mold material. The four beam interference optical system was composed by the DOE(Diffractive Optical Element) and two lenses. The laser intensity distribution of four beam interference was explained by an interference optics point of view and by the image optics point of view. We revealed that both views showed the same result. The laser power distribution of a $1{\mu}m$ peak pattern was made by the four beam interference optical system and measured by the objective lens and CCD. A $1{\mu}m$ pitch dot pattern on the mold material was fabricated and measured by SEM(Scanning Electron Microscopy).

• Macromolecular Research
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• 제17권3호
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• pp.181-186
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• 2009

We fabricated ordered micro/nano patterns induced by controlled dewetting on the topographically patterned PS/P4VP bilayer thin film. The method is based on utilizing microimprinting lithography to induce a topographically heterogeneous bilayer film that allows the controlled dewetting upon subsequent thermal annealing. The dewetting that was initiated strictly at the boundary of the thicker and thinner regions was guided by the presence of the topographic structure. The dewetting front velocity of the microdomains in the confined regions was linearly proportional to the measurement time, which enabled us to control the size of the dewet domain with annealing time. In particular, the submicron sized dot arrays between lines were generated with ease when the dewetting was confined into geometry with a few microns in size. The kinetically driven, non-lithographical pattern structures accompanied the pattern reduction to 400%. The pattern arrays on a transparent glass substrate were especially useful for non-circular microlens arrays where the focal length of the lens was easily tunable by controlling the thermal annealing.

• 마이크로전자및패키징학회지
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• 제26권2호
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• pp.9-14
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• 2019

The newly discovered properties of periodic nanoscale patterns have increasingly sparked research interests in various fields. Along this direction, it is worth mentioning that there had been rare studies conducted on interference exposure, a method of creating periodic patterns. Additionally, these few studies seemed to validate the existence of only exact quadrangle shapes and dot patterns. This study asserted the formation of wavy patterns associated to using multiple exposures of the ratio of the first exposure intensity to the second exposure intensity. Such patterns were designed and constructed herein via overlapping of two Gaussian beams relative to certain rotation angles, and with a submicron structure fabricated based on a 360-nm continuous-wave laser. Results confirmed that the proposed double exposure laser interference lithography is able to create circular, elliptical and wavy patterns with no need for complex optical components.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.272-273
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• 2013

Some living thingsuse micro- or nano- structures for living in nature. Scientists and engineers made efforts to mimic them, and they succeeded in making new types of applications. They used 'Namib desert beetle' to self-filling device by moisture harvesting and 'lotus leaf' to self-cleaning device by water repelling. 'Namib desert beetle' and lotus leaf have micro-patterns on their surface, which consists of hydrophobic or hydrophilic materials [1]. Moreover, micro-patterns on the surface make self-filling or self-cleaning property enhanced because of the surface roughness. Surface roughness enhances wettability [2]. Micro-pattern is a significant factor to make the surface be functional, so we want to make new types of functional surface by micro-patterning. In this work,we make several functional micro-patterns (radial, line, and dot arrays) using maskless lithography and analyze the characteristics of each micro-pattern. In order to analyze and understand surface characteristics, micro-patterns with varying sizes are investigated. All experiments are proceeded on mr-DWL5 photo resists coated on silicon wafers in same condition. All the experiments have demonstrated good performances about hydrophobic or hydrophilic property corresponding to their material and structural combinations. In radial micro-pattern, although the surface is flat, water drops on hydrophilic radial pattern can be convergent to a middle point and water drops on hydrophobic radial pattern can be divergent from the middle point. In line array micro-pattern, water drops can roll off along only one direction in parallel with the line arrays. Such phenomena might be mainly caused by the local change of surface roughness. From these results, controlling the movement and direction of water drops is made feasible without introducing a slope, which can potentially be used for new types of applications.

• 패션비즈니스
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• 제20권3호
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• pp.1-16
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• 2016

The purpose of this study is to analyze the differences in color, pattern, and texture of functional materials of outdoor clothing according to new senior women's psychological comfort. The data were collected from 163 female respondents aged 55-64 living in Busan. The results of the study are as follows. First, both the high and low psychological comfort groups preferred soft material the most. The high psychological comfort group particularly preferred soft textures and highly evaluated textured material in general. Second, both groups mostly preferred plain patterns while the high psychological comfort group preferred the dot pattern more. Third, in terms of colors, the high psychological comfort group preferred navy and purple, while the low psychological comfort group preferred brown. As to achromatic colors, both groups preferred black the most with the high psychological comfort group preferred gray and white more than the other group. Fourth, the high psychological comfort group preferred colors and patterns of clothing that made one look the most slimming, while the low psychological comfort group strongly preferred colors and patterns of clothes. Therefore, our results suggest that new senior women have a strong interest in outdoor clothing, not only in terms of textile functions, but also having interest in textile designs. In particular, the new silver women value psychological comfort in colors more than patterns of textile design.

• 복식
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• 제20권
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• pp.17-31
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• 1993

The purpose of this study is to inquire into the influence of appearance cues on the intellectual impression formations, whether there are differen-ces in the impression formation between the case which the appearance is partially percepted and the case wholely percepted. The study consists of the experiment of the factorial design with 5 independent variables of Face (intellectual and social), Hair Style (intellec-tual and social), Clothing Style (intellectual and social), Textile Pattern(single, color, dot, and stri-pe), and Presentation Level of stimuli (upper-half and full-length). The outcomes of study are as follows : 1) The intellectual impression formation was influenced by face, clothing style, and textile pat-tern, but clothing style and textile pattern were more influential than face. When the models with intellectual face wore in intellectual clothing style, they gave more additional intellectual impression. And when intellectual clothing was in single color, it conveyed more intellectual impression. Hair style had no main effect but it influenced on the impression formation through interaction with other variables. 2) There were differences in the formation of the intellectual impressions between the case the appearance was partially percepted and the case wholely percepted. The case of full-lenth pressen-tation was more influential than that of upper-half presentation.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.239-242
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• 2006

LCD-BLU (Liquid Crystal Display - Back Light Unit) is one of kernel parts of LCD unit and it consists of several optical sheets(such as prism, diffuser and protector sheets), LGP (Light Guiding Plate), light source (CCFL or LED) and mold frame. The LGP of LCD-BLU is usually manufactured by forming numerous dots with $50{\sim}200$ um in diameter on it by etching process. But the surface of the etched dots of LGP is very rough due to the characteristics of the etching process during the mold fabrication, so that its light loss is high along with the dispersion of light into the surface. Accordingly, there is a limit in raising the luminance of LCD-BLU. In order to overcome the limit of current etched dot patterned LGP, optical pattern design with 50um micro-lens was applied in the present study. The micro-lens pattern fabricated by modified LiGA with thermal reflow process was applied to the optical design of LGP. The attention was paid to the effects of different aspect ratio (i.e. $0.2{\sim}0.5$) of optical pattern conditions to the brightness distribution of BLU with micro-lens patterned LGP. Finally, high aspect ratio micro-lens patterned LGP showed superior results to the one made by low aspect ratio in average luminance.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.75-76
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• 2006

LCD-BLU (Liquid Crystal Display - Back Light Unit) is one of kernel parts of LCD unit and it consists of several optical sheets(such as prism, diffuser and protector sheets), LCP (Light Guide Plate), light source (CCFL or LED) and mold frame. The LGP of LCD-BLU is usually manufactured by forming numerous dots with $50{\sim}200{\mu}m$ in diameter on it by erosion method. But the surface of the erosion dots of LGP is very rough due to the characteristics of the erosion process during the mold fabrication, so that its light loss is high along with the dispersion of light into the surface. Accordingly, there is a limit in raising the luminance of LCD-BLU. In order to overcome the limit of current dot patterned LGP, optical pattern design with $50{\mu}m$ micro-lens was applied in the present study. Especially, the negative and positive micro-lens pattern fabricated by modified LiGA with thermal reflow process was applied to the optical design of LGP. The attention was paid to the effects of different pattern conditions to the brightness distribution of BLU with micro-lens patterned LGP. Finally, negative micro-lens patterned LGP showed superior results to the one made by positive in average luminance.

• 한국의류학회지
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• 제35권3호
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• pp.359-370
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• 2011

This study analyzes the textiles design of natural indigo dyed products in Korea and Japan. In this study, a total of 556 Korean natural indigo dyed products, and 2,730 Japanese natural indigo dyed products were used for analysis. The subjects of this study were 556 natural indigo dyed products and 2,730 Japanese natural indigo dyed products selling natural indigo dyed products which were found using search engine keywords of natural indigo dyeing and natural dyeing. Research and analysis was treated regarding the products, items, patterns, and the representation techniques of the patterns. The results of this study are as follows. In the pattern used for natural indigo dyed products, 71.4% of Korean products have no pattern, but 77.1% of Japanese products have patterns. On the representation techniques of the patterns, Korean products used tie-dyeing and a dip patterned fabric. While in the Japanese products, the most frequent patterning techniques were paraffin dye, followed by tie-dyeing, yarn-dyed and weaving, screen printing, and yarn-dyed and knitting. Regarding the kinds of patterns for natural indigo dyed products, only 8 kinds of patterns were used in Korean products; however, over 50 kinds of various patterns were used in Japanese products. Most patterns in the Korean products were ion patterns made by tie-dyeing. While in the Japanese products, the most frequent patterns were stripe patterns, followed by flower, dot, and ion patterns. Based on these research results, the problems of the textile design of Korean natural indigo dyed products were that most of the products have no pattern, and even though there were patterns, they lacked variations between the products. While in the case of Japan, they used the traditional and modem patterns of various textile representation techniques.

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 동계학술발표회 논문집
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• pp.133-134
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• 2009

Cold temperature development (CTD) of electron beam (EB) patterned resists and subsequent dry etching were investigated for fabrication of nano-patterned Niobium (Nb). Bulky Nb fims on GaAs substrates were deposited with EB evaporation. Line patterns on Nb cathode were fabricated by EB patterning and reactive ion etching (RIE). Size deviations of nano-sized line patterns from CAD designed patterns are dependent on the EB total exposure, but it can be improved by CTD of EB-exposed resist. Line patterns of 10 to 300 nm widths of EB-exposed resist patterns were drawn under various exposure conditions of $0.2{\mu}s$/dot (total 240,000 dot) with a constant current (50 pA). Compared with room temperature development (RTD), the CTD improves pattern resolution due to the suppression of backscattering effect. RIE with $CF_4$ was performed for formation of several nano-sized line patterns on Nb. Each EB-resist patterned samples with RTDs and CTDs were etched with two different $CF_4$ gas pressures of 5 Pa. Nb etching rate increases while GaAs (or ZEP) etching rate decreases as the chamber pressure increases. This different dependent of the etching rate on the $CF_4$ pressure between Nb and GaAs (or ZEP) has a significant meaning because selective etching of nano-sized Nb line patterns is possible without etching of the underlying active layer.