• Korean Journal of Optics and Photonics
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• v.2 no.4
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• pp.233-241
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• 1991

Structures, fabrication, and characteristics of top-surface-emitting GaAs four quantum well microlaser are described. The microlasers have good room-temperautre CW characteristivs. The maximum CW laser output is >3mW from a 30 $\mu\textrm{m}$ diameter microlaser and the maximum differential quantum efficiency is >70% from a 10 $\mu\textrm{m}$ diameter microlaser. Active surface emitting laser logic devices are designed and fabricated as a discrete version of a top-surface-emitting laser and heterojunction phototransistor. The active surface emitting laser logic device have high optical gain (>20 overall, >200 differential) and very high on/off ratio. Two-dimensional arrays of top-surface-emitting microlasers and active surface emitting laser logic devices will be critical elements for optical computing, photonic switching and neural network applications.

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.241-242
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• 2006

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.319-320
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• 2009

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.46-47
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• 2004

• Proceedings of the Optical Society of Korea Conference
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• 2005.07a
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• pp.324-325
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• 2005

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.219-220
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• 2009

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.257-263
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• 2018

The purpose of this study is to develop an automatic inspection system for a part of the differential drive gear into the transmission. This technology will make using the microvision automatic test equipment and automatic test equipment microlaser. This is that the operator intends to make the defect rate 0 in the inspection stage of the product which has been carelessly processed. The equipment developed in this research project will be applied to many areas. Packaging companies, nut bolt processing company, precisely supplier for printing on top of the semiconductor, SMT, etc. The company wants to sell the vision inspection equipment for various applications. If the defective rate of 0 is achieved through this research project, it is also possible to secure a stable supply from the parent company, and to lay the foundations for exporting based on product reliability. When the automatic inspection system is applied to domestic automobile parts processing companies, the reliability of automobiles in Korea will be greatly increased.

• Korean Journal of Optics and Photonics
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• v.4 no.3
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• pp.294-300
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• 1993

Monolithic NOR and INVERTER active optical logic devices inte- grated with surface-emitting microlasers, heterojunction photo- transistors(HPT) in parallel and resistors in series are characterized. The differential quantum efficiency of the typical AlGaAs superlattice microlaser integrated in the active optical logic devices is 15%. Current gain of the HPT is 57, when emitter-collector voltage and input optical power are 4 V and $50{\mu}W$, respectively. $57{\mu}W$ of output power from the active optical logic device decreases to zero when $47{\mu}W$ of input optical power is incident on the HPT part of the active logic device.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.21-29
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• 1998

The rare-earth orthoborate family, RM3(BO3)4 is known to be the most promising material for the microlaser host. To grow LaSc3(BO3)4 single crystal, the phase relation of the system LaBO3-ScBO3 was investigated by DTA method. LaSc(BO3)4 was the unique intermediate compound in the binary system the peritectic reaction point of which was 1495 ±2℃. Owing to the peritectic behavior of the compound, the crystal growth of the rare-earth Sc-borate was carried out by pulling from the melt-soultion of La1+xSc3-x(BO3)4. The optimal conditions for the growth of LaSc3(BO3)4 were determined by traditional CZ method : pulling speed 0.7mm/hr, rotation speed 7-10 rpm under reduction condition. Pt and Ir crucibles could be used for about 8-10 times of growth. The effect of thermal configurations on the temperature distribution was investigated. A special two-coordinate manipulator was made for the precise movement of thermocouples from the melt to the top of the furnace for several thermal configurations. The radial gradient on the melt surface depends strongly on the construction of the afterheater. On the other hand, the axial gradient was mainly propotional to both the opening degree of baffle plate and the mutual positions of crucible and heater.