• Proceedings of the KACD Conference
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• 2001.11a
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• pp.556-556
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• 2001

The application of the laser to the tooth hard tissue started from the removal of carious dentin with the laser performed by Goldman in 1964. With the development of the laser technology, the laser treatment with less descomfort such as pain, vibration, and noise, etc. has been attempted. Since it is difficult to give a suitable form for inlay restoration to a cavity prepared with laser, it has to be restored with adhesive resinous materials. However, various evaluation of adhesive properties of the resinous materials to lased tooth surface on the various conditions such as adgerent, irradiation condition, procedure of bond test, and adhesive materials used, etc. have been reported.(omitted)

• Journal of the Korean Society of Visualization
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• v.2 no.1
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• pp.52-56
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• 2004

Several visualization techniques of laser diagnostics are presented for combustion phenomena, including Mie scattering for flow, Rayleigh and Raman scattering spectroscopy for major species, laser-induced fluorescence for minor species, and laser-induced incandescence for soot. These techniques have been applied to understand the various combustion phenomena more clearly, including buoyancy-dominant flow system, diffusion flam oscillation, laminar and turbulent lifted flames, flame propagation along a vortex ring, and soot zone characteristics. The usefulness of laser diagnostics on a better understanding of physical mechanism is demonstrated.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.129-137
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• 2006

Polymer micro-fluidic devices were fabricated with laser processes. A UV laser and a femto laser were used to machine polymer micro-fluidic structures directly. This laser direct machining process suits the need of rapid prototyping, as in many applications changes from the original design are often required. As examples, two polymer micro-systems were developed: a micro-check valve and a micro diffuser pump. The micro fluidic devices can be applied for many applications such as clinical diagnostics and drug delivery. Advantages and disadvantages using polymers as a material for micro-fluidic applications are discussed.

• Laser Solutions
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• v.5 no.3
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• pp.21-30
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• 2002

In automotive industry, the studies about light weight vehicle and improving the productivity have been accomplished. For that, TRIP steel was developed and research for the laser welding process have been performed. In this study, the monitoring system using photodiode was developed for laser welding process of TRIP steel. With measuring light, neural network model for estimating bead width and tensile strength was made and weld quality classification algorithm was formulated with fuzzy inference method.

• Korean Journal of Optics and Photonics
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• v.25 no.3
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• pp.146-149
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• 2014

The homogeneous line broadening in EDF leads to unstable lasing and strong mode competition. In this paper a multiwavelength fiber ring laser that overcomes these effects by using variable attenuators between the DWDM and $1{\times}N$ coupler, has been proposed. Fiber ring lasers with four and eight wavelength outputs are implemented, and we show that the output powers can be adjusted with stable operation. The EDF ring laser has one four-wavelength output and four of single wavelengths, with OSNR of 50 and 60 dB respectively.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.453-454
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• 2008

femtosecond laser를 광원으로 하는 optical tweezers는 광포획 뿐만 아니라 비선형 현상을 발생시킬 수 있다는 장점을 가지고 있다. 그러나 높은 첨두 출력에 의하여 포획된 세포는 쉽게 손상되어 질 수 있다. 본 논문에서는 LTRS(Laser Tweezers Raman Spectroscopy)를 통하여 femtosecond laser와 CW laser에 의한 optical tweezers 상에서의 optical damage를 비교, 분석하였다.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1425-1427
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• 1994

Laser ablation of glass substrates (8K-7 and synthetic quartz) using a transversely excited atmospheric (TEA) $CO_2$ laser has been inverstigated to obtain high speed etching. The ablation occurs by local heating of a substrate with a focused TEA-$CO_2$ laser beam. The dependence of ablation rate on pulse count and repetition-rate of laser has been discussed.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2180-2182
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• 2000

Laser emission, a part of electromagnetic wave, has short propagation length in water, and the underwater applications of laser are limited. The acquisition of underwater imaging is possible only by using a blue-green laser since the blue-green range has relatively small absorption coefficient in water. We introduce the conditions of the laser required for underwater imaging and the attenuation characteristics of a blue-green laser used in water.

• Journal of the Korean Ceramic Society
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• v.37 no.1
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• pp.57-62
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• 2000

In this study, an attempt was made to demonstrate the possibility of using laser scribing method in manufacturing the barrier ribs of plasma display panel. The scribing with a CO2 laser was conducted on the green tape produced by the doctor blade tape casting method. Among the processing parameters, the quenching gas pressure, shape of mask, and laser power were found to affect the depth and angle of the scibed barrier ribs.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.12
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• pp.568-572
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• 2003

A longitudinal discharge heated copper vapor laser with internal diameter 28 mm and discharge length 1.3 m has been constructed and tested. At the discharging voltage 15.2 kV, pulse repetition rate 10 kHz, buffer gas pressure 40 mbar, and internal temperature of the laser plasma tube $1520^{\circ}C$, it delivers more than 30 W average laser outputs.