• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.181-186
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• 2000

The setup of the moir$\acute{e}$ deflectometry using the virtual grating was done, so the convergence and divergence of a pencil of ray was determined. The light source was He-Ne laser(3mW). The focal length of the first lens, the second lens being 18 mm, 250 mm respectively was used for the setup of the beam expander. The optics of the moir$\acute{e}$ deflectometry determining the vergence was used a diffraction grating(pitch = $1.6{\mu}m/line$) and a front flat reflection mirror. The effective focal length of the trial lens set was measured and compared with the theoretical value.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.1
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• pp.38-47
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• 1991

The purpose of this study was to investigate the effect of physical properties and grain line of fabrics on the drape properties of the flare skirt. Horizontal section overlap map was obtained by three dimensional Moire Topography, It was concluded drapability of the skirt obtained by the map can be used to determine the ease of the skirt. Grain line such as bias and lengthwise direction showed the difference of quality of the drape at the hem line; skirt made by bias direction showed evenly distributed flare and effective for the aesthetic point view. No difference was observed between cotton and polyester fabrics probably due to the similar characteristics of the fabrics.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.939-942
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• 2008

Moir$\acute{e}$s are a natural interference phenomenon which occurs whenever a transparent regular pattern plate is overlapped on another regular pattern plate. In the contact-type 3 dimensional imaging systems, the moires are inherent because an image display panel is seen through a viewing zone forming optical plate. The mathematical analysis of moires in the systems shows that they can be minimized by the proper selection of overlapping angles between them. The angle is different for pixels with different aspect ratios.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.4
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• pp.380-387
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• 2009

The reliability concerns of solder interconnections in flip chip PBGA packages are produced mainly by the mismatch of coefficient of thermal expansion(CTE) between the module and PCB. Finite element analysis has been employed extensively to simulate thermal loading for solder joint reliability and deformation of packages in electronic packages. The objective of this paper is to study the thermo-mechanical behavior of FC-PBGA package assemblies subjected to temperature change, with an emphasis on the effect of the finite element model, material models and temperature conditions. Numerical results are compared with the experimental results by using $moir{\acute{e}}$ interferometry. Result shows that the bending displacements of the chip calculated by the finite element analysis with viscoplastic material model is in good agreement with those by $moir{\acute{e}}$ inteferometry.

• Journal of the Optical Society of Korea
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• v.18 no.5
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• pp.538-545
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• 2014

Microlens array (MLA) films have been used as brightness-enhancement components in many illumination systems, such as a backlight, which should meet the industrial needs of low cost and high brightness performance. A hexagonally-arranged MLA (HA-MLA) was chosen due to its high filling factor, which was a prerequisite for achieving high brightness-enhancement capability. The moir$\acute{e}$ fringes produced in a film stack composed of two HA-MLA were investigated, under four different lens configurations, by optical simulation. It was found that randomizing the lens configuration, while keeping the filling factor high, was effective way to develop high-gain MLA films for backlight applications.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4155-4160
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• 2012

We characterized the physisorption of p-iodo-phenyl octadecyl ether molecules (I-POE) onto superlattice regions of graphite surfaces using scanning tunneling microscopy (STM). The formation of self-organized I-POE monolayers does not affect the overall structures of moir$\acute{e}$ patterns and their modulation periods. However, the packing density of the I-POE monolayer and the orientations of lamella structures were sensitive to the underlying superlattice structure. Depending on the bias voltage, the STM images selectively showed moir$\acute{e}$ pattern, I-POE layer, or both. Reflecting the local density of states at a certain energy level, the STM images thereby revealed the relative energy level scale of the superlattice with respect to the molecular orbitals of I-POE.

• Proceedings of the Optical Society of Korea Conference
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• 1999.08a
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• pp.126-127
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• 1999

• Journal of the Ergonomics Society of Korea
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• v.19 no.1
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• pp.109-125
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• 2000

The purpose of this study was to provide basic data for a more functional torso's pattern by analyzing multidimensional anthropometric measurements and the wearing condition. For the functional torso's pattern drafting, the fitness state of basic torso's patterns(4 types) was compared and evaluated from the cross-sectioned overlap maps by $moir{\acute{e}}$ topography. The results were as follows: 1. According to the measurements of four patterns by using the one-dimensional measurement, the amount of ease in girth item for pattern A was the smallest. The ease of clothes was affected by the position of dart, the amount of dart, and the drafting method. 2. As the results of wearing evaluation by $moir{\acute{e}}$ topography method, pattern B had the largest space length for hip part, pattern A, C and D had the largest space length for bust part. Also, in the all measurement items, pattern A had the smallest amount of ease. The space length for bust and waist part of pattern B was smaller than pattern D, but, for abdomen and hip part of pattern B was larger than pattern D. The space length of pattern C was revealed intermediate for all measurement part. 3. The significant difference of space length of each pattern was shown in all parts except bust part(p<.05). The amount of space was affected by the amount of dart, the characteristics of the somatotype, and the drafting method.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.1
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• pp.97-106
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• 2011

In this study, viscoplastic material properties of solder alloy which is used in the electronics packages are inversely estimated. A specimen is fabricated to this end, and an experiment is conducted to examine deformation by Moir$\acute{e}$ interferometry. As a result of the experiment, bending displacement of the specimen and shear strain of the solder are obtained. A viscoplastic finite element analysis procedure is established, and the material parameters are determined to match closely with the experiments. The uncertainties which include inherent experimental error and insufficient data of experiments are addressed by using the method of computer model calibration. As a result, material parameters are identified in the form of confidence interval, and the displacements and strains using these parameters are predicted in the form the prediction interval.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.57-65
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• 2015

Electronic packages consist of various materials, and as temperature changes, warpage occurs because of the difference in coefficient of thermal expansion. Shadow $moir{\acute{e}}$ is non-contact, whole field measurement technique for out-of-plane displacement. However, the technique has low sensitivity above $50{\mu}m/fringe$, it is not adequate for the warpage measurement in some circumstance. In this paper, by applying phase shifting process to the traditional shadow $moir{\acute{e}}$, measurement system having enhanced sensitivity of $12.5{\mu}m/fringe$ is constructed. Considering Talbot effect, the measurement is carried out in the half Talbot area. Shadow fringe pattern having four times enhanced sensitivity is obtained by the image process with four shadow fringes. The measurement technique is applied to the fibered package substrate and coreless package substrate for measuring warpages at room temperature and at about $100^{\circ}C$.