• 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.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.911-914
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• 2007

We developed the laser annealing system using green laser of 261W(5kHz) and 75.5mJ/pulse(2kHz). We confirmed that this system makes it possible to form two kinds(large or uniformed grain) of poly-Si by changing its polarized directions. By using ${\mu}-crystal-Si$ as irradiated films, grain size uniformity is better than that using a-Si.

• Journal of the Korean Ceramic Society
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• v.55 no.6
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• pp.581-589
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• 2018

This work concentrated on the effect of different laser beams on the microstructure and dielectric properties of $BaTiO_3$ nanoparticles at different calcinations times during the gelling preparation step. The nanoparticles were prepared by the sol-gel method. A green (1000 mW, 532 nm) and red laser beam (500 mW, 808 nm), were applied vertically at the center of stirring raw materials. The samples were sintered at $1000^{\circ}C$ for 2, 4, and 6 h. X-ray diffraction (XRD) analysis showed that samples prepared under the green laser have the highest purity. The FT-IR spectra showed that the stretching and bending vibrations of TiO bond without any other bonds, which are compatible to the X-ray diffraction (XRD) results. Samples were characterized by transmission electron microscopy (TEM), Scan electron microscopy (SEM), and UV-Visible spectrophotometer. Characterization showed the samples prepared under the green laser to have the highest particle size (~ 50 nm) and transparency for all sintering durations. Laser beam effects on electrical characterization were studied. BT nanoparticles prepared under the green laser show the higher dielectric constant, which was found to increase with sintering temperature.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.476-477
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• 2009

The smallest green laser containing a built-in temperature controlling unit has been demonstrated. The device volume was just 0.5 cubic centimeters, which is nearly the same size as existing red and blue diode lasers, has an electrical-to-optical conversion efficiency of 10% and 150 mW power output. Furthermore as an alternative approach for compact green laser development, a quasi-phase matching method with wide spectral bandwidth for the reduction of speckle noise will be presented.

• Korean Journal of Acupuncture
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• v.25 no.2
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• pp.199-210
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• 2008

Objectives : This study was performed to investigate the effect of invasive laser acupuncture therapy with green light (LAT-G) at HT7(Sinmun), SP3(Taebaek) on the blood pressure in hypertensive rat induced by two kidney one clip. Methods : The experiments were performed on Sprague Dawley rats. 2K1C hypertension model was prepared by constricting the left renal artery with a sliver clip. Animals were divided into four groups, which were simple acupuncture treatment group with straight needle insertion on the square(AT-SS), acupuncture treatment group with reducing manipulation in the opposite channel direction(AT-RD), laser acupuncture treatment group with green light 532 nm, 10mW power in the opposite channel direction(LAT-G10) and laser acupuncture treatment group with green light 532 nm, 20mW power in the opposite channel direction(LAT-G20). The treatments were performed once per two days for 10 days. Results : Body weight was increased significantly in LAT-G20 group compared with AT-RD group. The blood pressure was significantly decreased in LAT-G20 and LAT-G10 groups compared with AT-SS group. Conclusions : These results suggest that green laser acupuncture therapy at SP3 ${\cdot}$ HT7 is more effective than straight needle insertion on the square for controlling hypertension. It is possible that invasive green laser acupuncture therapy (532 nm) can be used as a reducing method of the traditional acupuncture techniques.

• Transactions on Electrical and Electronic Materials
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• v.16 no.2
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• pp.65-69
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• 2015

Low level laser therapy (LLLT) has facilitated an improvement in acupuncture treatment. In this study, we stimulated Shaochong (HT9), Dadun (LR1), Shaohai (HT3), and Yingu (KI10) acupoints with pulsed laser diodes 532 nm [green laser] and 658 nm [red laser] in rats with induced middle cerebral artery occlusion(MCAO). The animals were divided into 6 groups: intact control; MCAO control without LLLT; LLLT with red laser at HT9·LR1 and HT3·KI10 (RR); LLLT with green laser at HT9·LR1 and HT3·KI10 (GG); LLLT with green laser at HT9·LR1 and red laser at HT3·KI10 (GR); and LLLT with red laser at HT9·LR1 and green laser at HT3·KI10 (RG). We evaluated the immunohistochemical changes in the hippocampal CA1 region, and complete blood count changes. Compared to the MCAO control group, the RG group showed a significant decrease in Bax and cytochrome c levels in the hippocampus, and a significant increase in hemoglobin level, hematocrit, total white blood cell, neutrophil, lymphocyte, monocyte, and erythrocyte counts.

• Korean Journal of Optics and Photonics
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• v.14 no.3
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• pp.292-297
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• 2003

A diode-pumped single-mode Nd:YV $O_4$ green laser was developed. Frequency doubling of the laser was achieved by using an intracavity KTP generated green beam (532 nm). By comparing the diode laser spectrum with absorption spectrum of the Nd:YV $O_4$ crystal, we found optimal operating temperature of the diode laser. From output power measured for various mirror curvatures and cavity lengths, we found the optimal matching of TE $M_{00}$ mode with the pump beam gives the best efficiency. When the pump power was 1.9 W, 80 ㎽ of TE $M_{00}$ mode green beam was obtained. We tried to get a single longitudinal mode lasing as the fluctuation of the laser power was caused by the shift of longitudinal modes and the beating between the modes. We tested the intracavity etalon method and birefringent filter method for single mode operation. The etalon method resulted in the best single mode output power of 60 ㎽. The power fluctuation of the single-mode laser was reduced to 1/10 of that of the multi-mode laser.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1335-1336
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• 2008

A compact diode-pumped microchip(DPM) green light source which consist of pump LD, $Nd:YVO_4$, KTP and a built-in thermoelectric element has been fabricated for laser projection display. The volume of the source is as small as $0.7\;cm^3$ and we obtained the output power of 25mW with the average electric power consumption in pump LD of 304mW which correspond to the electrical-to-optical efficiency of 7.8%. Another approach using quasi phase matching(QPM) technique has been attempted. We obtained the output power of 90mW of green beam with 350mW pumping of a $Nd:YVO_4$ laser with 20-kHz rep. rate and 10-ns pulse duration. Detailed characteristics and issues of the DPM and QPM green light sources will be addressed.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.118-123
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• 2005

We have investigated the fabrication of Si nanoparticles and $C_{60}$ thin films by pulsed laser ablation. By atomic force microscopy(AFM), the laser-deposited $C_{60}$ thin film was verified to have surface far smoother than the surfaces of films produced by the conventional evaporation method. The Si deposited at a He atmosphere of 0.2 Torr was with about $60{\AA}$ height of the Si nanoparticles, suggesting that it was uniformly deposited. We observed visible green emissions spectra in the $Si/C_{60}$ multilayer films after laser annealing. It is considered that this green emissions is occurred from SiC particles, which is produced reaction of Si nanoparticles with $C_{60}$ by laser annealing.

• 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.