• Corrosion Science and Technology
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• v.13 no.4
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• pp.125-129
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• 2014

Shinning spot defects on galvanized steel sheets were studied by optical microscope, scanning electron microscope(SEM), Energy Dispersive Spectrometer (EDS) and Laser-Induced Breakdown Spectroscopy Original Position Statistic Distribution Analysis (LIBSOPA) in this study. The research shows that the coating thickness of shinning spot defects which caused by the substrate defect is much lower than normal area, and when skin passed, the shinning spot defect area can not touch with skin pass roll which result in the surface of shinning spot is flat while normal area is rough. The different coating morphologies have different effects on the reflection of light, which cause the shinning spot defects more brighter than normal area.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.9
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• pp.22-29
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• 1997

This paper describes a three dimensional profile measurement method for sheet metal products which have flexible and porous sculptured surfaces. Shadow masks are used as measuring objects for practical implementation or this study. The shadow masks are located inside the fluorescent glasses of monitors for televisions or computers and used to prevent electron guns from interfering between pixels. Three dimen- sional surface profiles are measured by adopting a software autofocusing technique to capture focused images. The experimental results show that the method is very effecive and suitable for sheet meal prod- ucts with flexible and porous surfaces.

• Transactions on Electrical and Electronic Materials
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• v.14 no.1
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• pp.9-11
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• 2013

The AZO/Ag/AZO multilayer films were deposited on polyethersulfone (PES) substrate by using facing target sputtering methods at room temperature. The AZO/Ag/AZO multilayer films with polymer substrate had advantages, such as low sheet resistance, high optical transmittance in visible range and stable mechanical properties. From the results, the AZO/Ag/AZO multilayer films (50/12/50 nm) demonstrated a sheet resistance of 11 ${\Omega}/{\square}$ and average transmittance of 87% in visible range (wavelength of 380-770 nm). Moreover, the multilayer showed stable mechanical properties compared to the single-layered AZO sample during the bending test due to the existence of the ductile Ag metal layer.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1225-1228
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• 2005

Barrier ribs in the plasma display panel(PDP) function to maintain the discharge space between the glass plates as well as to prevent optical crosstalk. Patterning of barrier ribs is one of unique processes for making PDP. In this work photosensitive barrier rib pastes were prepared by incorporating binder polymer, solvent, functional monomers photoinitiator, and barrier rib powder of which surface was treated with fumed silica particles. Study on the function of materials for the barrier rib paste were undertaken. After optimization of paste formulation and photolithographic process, it was found that photolithographic patterning of barrier ribs with photosensitive barrier rib green sheet could be used in the fabrication of high resolution PDP.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.401-406
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• 2003

New planar discharge structured AC-PDP has been developed by using TFCS (Thick Film Ceramic Sheet) technology. By applying TFCS to AC-PDP, a sustaining electrode and scanning electrodes are embedded in the TFCS. It is shown that panel performances such as electrical and optical characteristics are superior to commercialized coplanar AC-PDP as well as cost reduction. Moreover the experimental result shows panel performances can be improved drastically by continuous development.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.353-356
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• 2002

Planar laser induced fluorescence(PLIF) has been widely used to obtain two dimensional fuel distribution. Preliminary investigation was performed to measure quantitative air excess ratio distribution in an engine fueled with LPG. It is known that fluorescence signal from acetone as a fluorescent tracer is less sensitive to oxygen quenching than other dopants. Acetone was excited by KrF excimer laser (248nm) and its fluorescence image was acquired by ICCD camera with a cut-of filter to suppress Mie scattering from the laser light. For the purpose of quantifying PLIF signal, an image processing method including the correction of laser sheet beam profile was suggested. Raw images were divided by each intensity of laser energy and profile of laser sheet beam. Inhomogeneous fluorescence images scaled with the reference data, which was taken by a calibration process, were converted to air excess ratio distribution. This investigation showed instantaneous quantitative measurement of planar air excess ratio distribution for gaseous fuel.

• Journal of ILASS-Korea
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• v.5 no.1
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• pp.23-29
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• 2000

Recently the laser sheet technique has been developed to improve our limited understanding of the in-cylinder diesel combustion. The technique is capable of high temporal and spatial resolution, so that it is proved to be an adequate combustion diagnostics to find out exhaust emission formation. The optical signals of LIS(Laser Induced Scattering) and LII(Laser Induced Incandescence) images show informations for soot concentration within the optically accessible diesel engine. The LIS and LII signal images of soot concentration provide new insight into where and when soot occurs in a diesel engine.

• Laser Solutions
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• v.11 no.3
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• pp.16-20
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• 2008

The lap Joint welding of 6K21 aluminum sheets by Nd:YAG laser were performed with an aluminum 5183 filler wire or without a filler wire. The porosity of laser welding beads were observed through an optical microscope and X-ray photography with various levels of welding speed and gap size. The porosity was observed in the gap between upper and lower sheet near a heat affected zone when autogenous welding. Decrease of welding speed and use of AA5183 filler wire reduced porosity significantly.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.303-308
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• 2012

One dimensional line edge detection sensor was investigated for the application to detect line or edge of wide sheet winding to cylindrical roller. Line edge detection sensor was realized using align-free 1:1 optical system having 1 convex lens and by processing sum or difference of signals from two photo-diodes in a bi-cell photodetector. Line width up to 0.1mm on object having various materials and colors was detectable, and the deviation of wound sheet was found to be under 0.2mm.

• Korean Journal of Optics and Photonics
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• v.11 no.3
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• pp.152-157
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• 2000

Post-deposition vacuum annealing effects in electron-bearn-evaporated indium tin oxide (ITO) films have been investigated by the change of transmittance, sheet resistance and crystalline structure with annealing temperature ( $200-335^{\circ}C$) and oxygen partial pressure ($1\times^10^{-5}-1$\times10^{-4} torr$) in air and vacuum. The sarnples were polycrystalline films with a preferred orientation in the (222) plan. High quality films with sheet resistance as low as 62 Q/O and transmittance over 99% (absentee layer at 500 nm) have been obtained by suitably controlling the vacuum annealing pararneters.neters.