• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2007.11a
• /
• pp.85-88
• /
• 2007

현재 LED 전용의 렌즈로서 개발되어 있는 제품들은 대부분이 매우 좁은 빔각을 가지는 집광렌즈이지만 이를 사용하여 다양한 조명기구의 배광을 달성하기는 불가능하다. 본 논문에서는 가로등 형 배광을 가지는 대칭형, 비대칭형 배광을 가지는 선형 렌즈의 설계를 진행하고 그 성능을 시뮬레이션 하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.10a
• /
• pp.27-30
• /
• 2009

LED를 광원으로 사용하는 조명기구는 용도에 맞는 적합한 배광을 가져야 한다. 도로조명기구의 경우 기능적인 측면에서 보다 세밀한 배광제어를 필요로 하며, 비대칭 형태의 배광을 갖는다. 도로조명의 배광을 달성하는 렌즈와 비대칭 배광을 구현하기 위한 렌즈를 설계하고 반사판이 포함된 형태의 광학계 설계안을 제시하였다. 형상 및 사이즈 측면이 고려되었으며 설계된 렌즈 및 광학계는 광학성능 시뮬레이션 프로그램을 사용하여 성능을 검증하였다.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.2243_2244
• /
• 2009

본 논문에서는 알루미늄 재질로 된 방열판과 PCB에 1[W]급 LED 14개를 모듈 방열 설계 하여 COMSOL Multiphysics로 시뮬레이션을 통한 결과, 경계면 온도는 약 $80^{\circ}C$, Max.온도$141^{\circ}C$, Min.온도$20^{\circ}C$까지 변화로 실 제작에 근접한 온도 확인이 가능함을 확인 할 수 있었다.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.2247_2248
• /
• 2009

20W급 LED 형광등 광학 설계를 위하여 1W ${\times}$ 20개와 2W ${\times}$ 10개의 두 가지 경우로 Photopia를 이용하여 시뮬레이션 하였다. 이를 통하여 배광곡선, 조도분포, 균제도를 분석하였으며, 그 결과 배광 분포는 1W ${\times}$ 20개가 균일하며, 경제성은 2W ${\times}$ 10개가 우수함을 확인 할 수 있었다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.81-83
• /
• 2017

우리 삶의 다양한 분야에서 ICT 기술을 적용하여 편의성과 활용성이 증대되고 있다. 본 논문에서는 최근 다양한 응용에 활용되고 있는 아두이노(Arduino)를 기반으로 사람의 움직임에 따라 이용할 수 있는 Accelerometer와 FSR 센서를 사용하여 RGB LED Strip을 제어하고 여러가지 색상을 다양한 패턴으로 나타나게 하며, 해당 움직임을 모니터링할 수 있는 시스템을 제안한다. 이는 사람의 움직임 또는 동작을 취하는 다양한 신체부위에 적용해 볼 수 있다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.05a
• /
• pp.182-185
• /
• 2009

조명용 광원으로써 LED의 사용이 늘어나고 있고, 앞으로도 더욱 늘어날 추세이다. 하지만 현재 출시되는 LED를 조명 용도에 적합한 배광을 구현하는 렌즈를 설계하는 작업은 설계 방법이 어렵고, 많은 반복 작업을 동반한다. 이에 새롭게 출시된 Photopia 3.0 Version의 PODT 기능을 이용해 LED 렌즈를 쉽게 설계할 수 있는 방법을 소개하고, 간단한 렌즈 설계를 수행 하였다.

• Proceedings of the KIPE Conference
• /
• 2012.07a
• /
• pp.242-243
• /
• 2012

In this paper, 200 W power supply for LED driver has been designed, analyzed, simulated and tested. Input AC voltage of 100VAC-240VAC was converted to DC voltage by high power factor converter. Output voltage was controlled, and output current was controlled by constant current when output current was reached to LED maximum rated current. By simulation and experimental test, voltage and current control and high power factor characteristics are verified.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.28 no.6
• /
• pp.408-413
• /
• 2015

Road lighting has emerged in importance as an essential system to secure safety and visibility for drivers and pedestrians. According to the Road Lighting Standards (KS A 3701), the luminance uniformity (U0) should be 0.4, the luminance uniformity for lanes (UI) should be 0.5, and a threshold increment (TI) of 10% should be satisfied. In this study, we conducted simulations using the Relux program in which the secondary optical lens was applied to a 21 W engine. Ten LED engines were installed on a two-way four-lane road, and the simulation result satisfied the requirements with U0 0.47, UI 0.63 and TI 8%. The U0, UI, and TI were compared with the angle of the LED streetlight varied in the range of $9^{\circ}{\sim}15^{\circ}$ with $0.5^{\circ}$ intervals. The range was selected as ${\pm}25%$ of the standard inclination angle of $12^{\circ}$ according to the Road Lighting Standard. The U0 was high and the UI and TI were low when the tilting angle was in the range of $9.5^{\circ}{\sim}10.5^{\circ}$. Consequently, an optimum-design of lighting distribution was obtained for the concrete two-way four-lane road when the inclination angle was $9^{\circ}$.

• Korean Journal of Optics and Photonics
• /
• v.27 no.2
• /
• pp.73-80
• /
• 2016

In this paper, we report the results of a study on the design and fabrication of a light-guiding plate (LGP) using a hybrid light-emitting diode (LED) and sunlight source that can be applied to a photobioreactor. LGP patterns for the LED source were designed and engraved on an LGP, together with previously reported patterns for a sunlight source. A control system for the hybrid LGP was designed to maintain the output photon flux density (PFD) from the LGP at a constant value. When the target value of the output PFD was set to $70{\mu}E/(m^2{\cdot}s)$, the error range of the output PFD was found to be within ${\pm}2%$.

• Journal of the Microelectronics and Packaging Society
• /
• v.22 no.4
• /
• pp.71-76
• /
• 2015

Recently, light emitting diodes (LEDs) have been studied to improve their efficiencies for the uses in various fields. Particularly in the aspect of chip structure, via hole type vertical LED chip is developed for improvement of light output power, and heat dissipations. However, current vertical type LEDs have still drawback, which is current concentration around the n-contact holes. In this research, to solve this phenomenon, we introduced isolation layer under n-contact electrodes. With this sub-electrode, even though the active area was decreased by about 2.7% compared with conventional via-hole type vertical LED, we could decrease the forward voltage by 0.2 V and wall-plug efficiency was improved approximately 4.2%. This is owing to uniform current flow through the area of n-contact.