• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.6
• /
• pp.18-27
• /
• 2011

LED lighting because of high efficiency, long life, friendly environment, as a general lighting of the next generation, has been substituted for incandescent bulb and fluorescent lamp. The proposed system for use of solar battery is the intelligent controller for LED street lights which is improved the method of battery charging and charging efficiency in winter to extend battery life cycle, controlled lighting current according to SoC and in steps. Also, it is implemented emotional lighting which is controlled with the surrounding environment, by using colorful sub LED to take up 10[%] of a source of total light, white LED. As a lab results, the proposed system was implemented functions to adapt to the environmental changes, and improved the charging efficiency and battery life cycle.

• Proceedings of the KIPE Conference
• /
• 2013.07a
• /
• pp.352-353
• /
• 2013

본 논문에서는 형광등 용 전자식 안정기 호환을 위한 LED 구동회로를 제안한다. 일반적인 전자식 안정기는 기본적으로 부하 전류제어를 하지 않으므로 형광등보다 소모전력이 낮은 LED 구동 시 과도한 전압상승이 발생된다. 따라서 기존의 전자식 안정기 호환용 LED 구동회로의 경우 소자내압을 낮추기 위해 과도한 Damping에 의존하므로 효율이 저조하고 안정기 호환성이 크게 떨어지는 문제점이 있다. 반면 제안된 회로는 별도의 Damping 회로없이 LED 구동회로의 등가 임피던스를 시비율에 따라 가변 함으로써 기존 문제점을 획기적으로 개선할 수 있다. 최종적으로 호환성 및 동작성능에 대한 타당성 검증을 위해 20W급 전자식 안정기에 적용하여 고찰된 실험결과를 제시한다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2006.05a
• /
• pp.154-156
• /
• 2006

A few ten mW white LED can substitute for the indicator light source and it is required to study several watt multi-chip semiconductor light sources in order to replace the light sources for general illumination such as incandescent lights and fluorescent lanes. Since the optical technology used for several mW white LED light source uses only 30% to 52% of the light it is required to develop the design technology of optical system and lens to improve the efficiency more than 80% for insuring the high power of white LED. In this paper, we designed and fabricated new structure reflector to increase the efficiency and is easy to make high power multi-chip LED lamp.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.10
• /
• pp.235-242
• /
• 2014

LED lighting control technique is one of the ongoing research areas for efficient management of LED lighting. In this paper, we design and implementation of LED street lighting remote control system which have a wired and wireless communication function for LED street lighting remote control. The implemented system can automatically dimming and individual(or consolidated) LED street lighting via RS-485/422 or Wi-Fi. In experimental results, the implemented remote control system was satisfactory for all of the desired functions.

• The Journal of the Korea Contents Association
• /
• v.10 no.5
• /
• pp.62-69
• /
• 2010

LCD panel need BLU(Back Light Unit) that is outside source of light because can not emit light voluntarily. BLU is used in LCD module and is used in tester that examine LCD panel's badness. Lately, BLU had changed from CCFL(Cold Cathode Fluorescent Lamp) to LED(Light-Emitting Diode) fast. CCFL need extra-high tension power and produce much heat and is difficult to keep fixed brightness. LED is few electric power wastage and keeps fixed brightness. But, BLU that is used to detector that examine the LCD module is using CCFL until recently. This paper develops LED BLU that can examine LCD panel's badness. Also, this manufactures LED BLU to 24 inch size to examine all LCD panels(12~24 inch), and develops so that LED BLU may operate according to LCD panel's size.

• Korean Institute of Interior Design Journal
• /
• v.21 no.6
• /
• pp.129-136
• /
• 2012

As the importance of eco-friendly and energy saving issues are emphasized in lighting as consciousness about energy saving is elated worldwide, demand for natural resources such as gas increases, supply of LED lighting is spread. Owing to white LED's development and price fall. It is expected to LED High Luminance Emitting Diode. LED's brightness and long life-time that surpass fluorescent light in the latest as well as is used by back light source of thin film LCD, low electric power attrition rate by advantage do and widen the market at the world lighting lamp market that is potential market. Accordingly, study about suitability of LED lighting is activated but space that apply actual LED lighting fixtures yet is less and advanced researches about LED fixtures' applied apaces are slight compared to existing light source up to now because is not many on this. The result of the experiment shows similar tendency with the existing light sources'. Through a psychological reaction experiment in the LED lighting experiencing space that can control of color temperature and lighting level, this study is wished to use to the data for lighting design of space that LED lighting fixtures are applied hereafter.

• Journal of IKEEE
• /
• v.25 no.2
• /
• pp.267-272
• /
• 2021

Recently, attention has been focused on renewable energy and carbon neutrality to resolve fossil energy depletion and environmental problems. In addition, high-rise urban buildings and an increase in building energy are rapidly increasing. There are many restrictions on installing solar power in urban areas. In addition, as buildings become taller, a lot of low-light environments in which shade is formed occur. Therefore, in this study, we intend to develop a power plant capable of generating electric power in an outdoor low-light environment and indoor lighting environment. The power plant in a low-light environment used a dye-sensitized solar cell. A unit cell and a 20cm×20cm module were manufactured, and the electrical characteristics of the power plant were measured using light sources of LED, halogen lamp, and 3-wavelength lamp. The photoelectric conversion efficiency of the unit cell was 17.2%, 1.28%, 19,2% for each LED, halogen lamp, and 3-wavelength lamp, and the photoelectric conversion efficiency of the 20cm×20cm module was 10.9%, 8.7%, and 11.8%, respectively. In addition, the maximum power value of the module was 13.1mW, 15.7 mW, and 14.2 mW for each light source, respectively, confirming the possibility of power generation in a low-light environment

• Journal of the Korean Ceramic Society
• /
• v.43 no.5 s.288
• /
• pp.304-308
• /
• 2006

We have synthesized a $Eu^{2+}-activated\;Sr_3MgSi_2O_8$ blue phosphor and $(Sr,Ba)_2SiO_4$ yellow phosphor and prepared white LEDs by combining these phosphors with a InGaN UV LED chip. Three distinct emission bands from the InGaN-based LED and the two phosphors are clearly observed at 405 nm, 460 nm and at around 560 nm, respectively. The 405 nm emission band is due to a radiative recombination from a InGaN active layer. This blue emission was used as an optical transition of the $Sr_3MgSi_2O_8:Eu$ blue phosphor and $(Sr,Ba)_2SiO_4:Eu$ yellow phosphor. The 460 nm and 560 nm emission band is ascribed to a radiative recombination of $Eu^{2+}$ impurity ions in the $Sr_3MgSi_2O_8:Eu$ and $(Sr,Ba)_2SiO_4$ host matrix. As a consequence of a preparation of UV White LED lamp using the $Sr_3MgSi_2O_8:Eu$ blue phosphor and $(Sr,Ba)_2SiO_4:Eu$ yellow phosphor, the highest luminescence efficiency was obtained at the ration of epoxy/two phosphor (1/0.2361). At this time, the CIE chromaticity was CIE x = 0.3140, CIE y = 0.3201 and CCT (6500 K).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.162-162
• /
• 2010

In this study, optical analysis for 100W LED safety street lighting was conducted. Experimental research on such single LED was the first undertaken. simulation modeling based on optical properties of single LED has compared single LED product also designed 100W simulation modeling has compared average road illuminance with Korean Industrial Standards for LED safety street lighting(KS C7658:2009). 100W safety street lighting (model: CE180-ST-OS) designed by simulation has been also compared between product and 100W simulation modeling, and error rates have showed average 5.6[%]. Designed 100W LED safety street lighting base on simulation modeling was proven by comparison experiments. Through the simulations and the corresponding analysis, it was found that the tested 100W LED safety street lamp had reasonable performance. Design method for LED safety Street lamps have been summarized, based on the optical analysis.

• Journal of Sensor Science and Technology
• /
• v.21 no.6
• /
• pp.429-433
• /
• 2012

In this paper, we reduced the optical noise interference in a visible light communication system using two color LEDs. In the transmitter, the original and the inverted signals of the transmitted data modulated a red LED and a blue LED, respectively. In the receiver, a differential detector which is composed of two photodetectors and an optical red filter detected the mixed signal radiated from the two LEDs. In an environment that the optical noise from a fluorescent lamp exists, the signal-to-noise ratio in this system was improved by about 20dB compared to that in the conventional system which uses a single LED and a single photodetector.