Earticle

In this paper we present the search on HC-06 Bluetooth based driver module for emergency LED Multi-Directional Indicator. Nowadays, a growing trends in which electronic displays such as LED, LCD or plasma monitors are being installed in public places like bars, stores, entertainment areas, restaurants, lobbies, etc. In this paper, the study is curried out on efficiency of HC-06 Bluetooth module based controller driver that relates generally to the field of emergency signage management systems for displaying various indicator contents remotely on electronic displays in public and privates venues. It allows user smart devices interaction remotely with digital signage by providing content for displaying on at least one display in a venue. Depending on the emergency case, HC-06 Bluetooth based driver module proves the high efficiency as well as good performance of processing and communicating remotely the indicator based message that is displayed from a venue management control system by using smart devices. The system combines smart device that linked to HC-06 Bluetooth module with ATmega168/328 embedded micro controller which result by switching the displayer containing the digital signage indicator based message.

고해상도 LED 모듈패키지는 AI 대시보드, 차량용 디스플레이 등 장시간 구동 환경에서 안정적인 광학 성능과 저전력 특성이 요구된다. 본 연구에서는 무기 나노 입자 기반 형광체를 적용한 고해상도 저전력 LED 모듈패키지를 제안하고, 그 특성을 분석하였다. Silica Quantum Dot 및 CdSe/ZnS Quantum Dot을 형광체로 사용하고, PEG 기반 블록 공중합체를 이용한 표면개질을 통해 분산 안정성을 확보하였다. FT-IR 및 ¹H NMR 분석을 통해 표면개질의 화학적 유효성을 확인하였으며, SEM 분석 결과 다양한 두께 조건에서도 광학 코팅층은 균일하고 안정적인 구조를 유지하였다. 또한 Blue LED 여기 조건에서 안정적인 발광과 RGBW 색 분리가 가능함을 확인하였다. 광학 성능 평가 결과, 휘도 안정성, 높은 광균일도, 우수한 광효율 및 연색성이 확보되었으며, 열적 거동 분석을 통해 장시간 구동 시에도 안정적인 동작 가능성을 확인하였다.

High-resolution LED module packages used in long-duration environments require stable optical performance and low power operation. This study proposes a high-resolution, low-power LED module package incorporating an inorganic nanoparticle phosphor and evaluates its characteristics. Silica quantum dots and CdSe ZnS quantum dots were used as phosphors, and dispersion stability was achieved through surface modification with a PEG-based block copolymer. FT-IR and 1H NMR confirmed the chemical validity of the modification, and SEM showed that the optical coating layer remained uniform and stable across a range of thicknesses. Under blue LED excitation, stable emission and RGBW color separation were demonstrated. Optical evaluation confirmed luminance stability, high luminance uniformity, excellent luminous efficacy, and high color rendering, while thermo-fluid analysis supported stable operation under long-term driving conditions.

Recently, studies have been actively conducted on light sources which can affect the growth rate of plants by using monochromatic lights which have light wavelength or combining them into mixed lights. The studies measure Photosynthetic Photon Flux Density (PPFD) according to the change of light quality of LED light source and research on the acceleration of plant growth. With red, blue, green and white mono-chromatic lights, this study fabricated 6 mixed lights. Then, with 3 mono-chromatic lights and 6 fabricated mixed light source, the study conducted comparison analysis on what effect optical properties and PPFD have on (the growth of) a plant (radish sprouts). As the result of analysis, in the same PPFD, it turned out that the speed of plant growth was faster in red mono-chromatic lights while the speed was similar in blue and white mono-chromatic lights and mixed lights.

본 논문에서는 웨어러블 디바이스용 SVGA급(800×600 pixel) Flip-chip 기반의 마이크로 LED 디스플레 이 광원 모듈 연구를 통해 마이크로LED 제작 공정을 개선하고, 시제품의 성능을 측정하여, 제품의 상용화 가능성 을 분석하였다. 먼저, 800×600 Flip-chip 기반 마이크로LED 어레이와 PM 구동 평가를 위해 32×32 어레이를 설 계 및 제작하여, 그 성능 및 제품화의 가능성을 확인하였으며, 제작 공정 기술에서 Self align 전극 형성 기술과 고집적화 어레이의 Mesa 형성을 위한 드라이 에칭 기술을 적용하여 생산성을 향상하였다. 본 연구를 기반으로 추 후 마이크로LED가 제품화시 향후 플렉서블 디스플레이 뿐만이 아닌 다양한 분야에서 적용 가능함으로 관련 산업 으로의 파급효과가 클 것으로 예상된다.

In this paper, we try to analyze the commercial potential of products by improving the micro-LED manufacturing process and measuring the performance of prototypes through research on the SVGA-class (800×600 pixel) flip-chip-based micro LED display light module for wearable devices. First, the 800×600 flip-chip based microLED array and the 32×32 array were designed and manufactured for PM driving evaluation, and their performance and potential for commercialization were confirmed. Productivity was improved by applying dry etching technology to form Mesa. Based on this study, when microLED is commercialized in the future, it is expected to have a large ripple effect on related industries as it can be applied to various fields as well as flexible displays in the future.

사물인터넷(IoT, Internet of Things)은 전자기기뿐만 아니라 모든 사물을 인터넷에 연결해 사물과 사물간, 그리 고 사물과 사람 간 상호작용을 하는 것을 뜻한다. 본 논문에서는 실험단계를 거쳐 최종적으로 WiFi에 의한 통신모듈이 완벽하게 동작하여 빨간, 초록, 파란색의 LED가 점멸됨을 확인하였다. 해외에서 각광을 받고 있는 사물인터넷 기반의 ‘개방형 플랫폼’인 아두이노(Arduino)와 통신모듈을 이용하여 LED Dimming 제어을 수행하였다.

The Internet of Things (IoT) refers to the interaction of objects and objects, as well as electronic devices, with all things connected to the Internet. In this paper, it is confirmed that red, green and blue LEDs are blinking because the communication module by WiFi finally operates through the experimental stage. LED dimming control was carried out using Arduino, a 'open platform' Internet-based object, which is in the limelight from overseas and a communication module.

최근 그린 IT 기술이 이슈화 되면서 전 세계적으로 탄소 배출을 낮추고 에너지 효율을 높일 수 있는 환경 친화적인 광원에 대한 연구가 활발히 진행되고 있으며, 특히 고유가와 환경오염 등의 문제로 기존의 백열등이나 형광등을 대체하기 위한 새로운 광원으로 LED가 크게 주목을 받고 있다. 본 논문에서는 저전력, 고효율, 고휘도의 LED 모듈에 온도, 습도, 조도, 그리고 이동 감지 센서를 포함한 복합 센서 모듈을 조합하여 가로등을 지능화하고, ZigBee 모듈을 이용하여 가로등 간에 IT기술인 USN 망 융합을 통하여, 가로등 시스템을 중앙에서 모니터링하고 지역 특성에 따라 선택적으로 가로등의 점멸을 원격으로 제어함으로써 효과적으로 에너지 절약을 극대화할 수 있는 Ad-Hoc망 기반 LED-IT-Sensor 통합 가로등을 설계하고 구현하였다.

With the issue of a Green IT Technology, studies on a environment-friendly luminous source that can reduce Carbon discharge and increase energy efficiency are actively progressed all over the world. Especially, with the problems of high oil price and environmental pollution, LED has made a great attention as a new luminous source that can replace the existing incandescent bulbs and fluorescent lights. In this paper, the proposed streetlight system becomes more intellectual by combining the low power consuming, high efficient, and high luminous LED module with a complex sensor module with temperature, humidity, illumination and motion sensors. Then, we design and implement the Ad-Hoc based LED-IT-Sensor integrated streetlight system that can maximize the energy savings efficiently with central monitoring system and selective remote dimming control by connecting them to the wireless ubiquitous sensor network(USN) using a Zigbee module.

In this paper, reduces the absolute temperature of the LED module, results of the experiments have been derived a method to improve the suitability heat dissipation structure and properties are as follows. First, FR-4 PCB size in consideration of the PCB LED module air-hole 3mm radius of the LED module area 10%, 20%, 30% ratio after a process of simulation to generate the air-hole on the PCB and the surrounding, 30%, 50×30mm intervals, when generating a fifty-two, applying the air-hole 3mm 10% of the radius of the area LED module obtained the results of temperature reduction than max. about 3.5℃ and min. about 3.1℃. Second, LED array interval and to be suitable experimental structure through the PCB air-hole generation plate type heat-sink for LED module to support the air-hole radius 40mm size to create a two and six and four, as a result of the simulation in progress, when air-hole number pairs of the increase, max. and min. temperature was reduced to obtain a formal conclusion by about 1~1.5℃. the air-hole 3mm 10% of the radius of the area applied LED module than max. about 4.5℃, min. about 4.2℃ results was confirmed reduction. As a result, to the suitable of the heat dissipation even if the LED module PCB material no matter how good, if the heat sink is not well designed structural cannot obtain a large effect.

The performance of high power LEDs highly depends on the junction temperature. Operating at high junction temperature causes elevation of the overall thermal resistance which causes degradation of light intensity and lifetime. Thus, appropriate thermal management is critical for LED packaging. The main goal of this research is to improve thermal resistance by optimizing and comparing nano-pore silicon-based thermal substrate to insulated metal substrate and direct bonded copper thermal substrate. The thermal resistance of the packages are evaluated using computation fluid dynamic approach for 1 W single chip LED module.

It is time to collect the consumer’s feedback to utilize the new variables of the system in any fields of processes or systems, yet the street sculptures using the streetlight as one of the offline advertisements are maintained and exposed in the form of unidirectional communication. The advertisement participation by the control for external advertisements or sculptures of the consumers can be a new paradigm of the street advertisement. This study aimed to design the system so as for multiple consumers of the advertisements to be able to control them, and to realize the remote sculptures exposed again by their participations. Additionally, LED advertisement streetlight which can be used efficiently in the street is feasible to self-charge by the sunlight, to control remotely, and to deliver the information of voltage and LED power consumption status. With this system, we anticipate to provide the users with the efficient illumination information and its control.

This paper presents a resonant isolated dc-dc converter for the LED backlight drive of the LCD TV module with a simple resonant half-bridge flyback converter power topology. The power topology structure of the proposed converter is isolated using the half-bridge flyback converter power topology with a transformer. The proposed converter switches complementarily its primary half-bridge switches and achieves high efficiency using the resonant circuit, composed of a resonant inductor and a blocking capacitor. The leakage inductance of the main transformer is used as the resonant inductor, and thus the proposed converter can be simplified. In this paper, the operational principle is analyzed, briefly, and a 100-W-class prototype is implemented based on the analysis. Then, it is shown that the proposed converter has good performance as a driver of the LED backlight drive of the LCD TV module through the experimental results of a 100 W prototype under a wide input voltage and load range.

It is difficult to measure junction temperature in the LED Module. According to the arrangement control unit and heat sink, temperature distribution is changed in the LED Module. A method of forecasting LED Module thermal resistance is suggested with measuring LED and PCB board temperature.

In this paper, we manufactured high flux LED module with Through Hole type. and we measured electrical, optical and thermal properties by driving type. LED module was composed with 8*8 arrangement form by using the glass epoxy PCB. Also, we measured the most suitable driving type with static voltage driving type and static current driving type. As a result, the LED Module of static voltage driving type showed high luminance characteristic than the static current driving type by suppling enough bias. However, the static current driving type showed more stable driving properties because of fast decreasing properties about brightness by increasing the surrounding temperature in the static voltage driving type. Also, due to Quantum confined Stark effect from piezoelectric field, the wavelength of bule peak shifted to long wavelength direction by increasing the surrounding temperature in the static voltage driving type.

In this paper, we were confirmed the optical characteristics of LED module by changing ambient temperature and driving current. When we supplied same driving current, the brightness quality drops due to an increased ambient temperature. The difference of brightness properties came out more large according to an increased driving current. Moreover, peak wavelength become shifted by long wavelength and declined output power by increasing driving current.

LED have many problem as narrow light view angle, high price, drift phenomenon of color coordinate, high heating problem for lower power, lower weight and small size. But, with the development of blue LEDs and the improvement of LED brightness, color variation are becoming more and more popular as lighting and application devices in this page, 1 used the Light Tools which was a simulation program in order to recognize optical a few characteristic of LEDs arrangement along reflector matrial and designed LED Arranged 5 phi LED in 5mm interval In the square that was $10{\times}10$ And designs a reflection board on pcb, structural design of PCB changed as five type. - Aluminum, Gold. Chromium, Nickel, Copper.

This paper describes the realization of the full-color to the degree of nearest white light by compounding high brightness Red, Green and Blue LEDs with appropriate proportional index. Once these three colors; red, green and blue are mixed, they are genearlly additive mixing and produce white light color contrasted to negative mixing. The luminous efficiency is defined as the product of the efficiency(lm/w), which indicates the degree of perceptual response by the human eye to unit energy(W) of light emitted by an active display devises and as the conversion efficiency of the device from electric power consumed to optical energy produced. We will deduce the each number of LEDs theoretically and design several shapes of LED displays for the full-color. Finally theoretical predictions will be compared with the measured data with different type of display designs.

Channel letter용 High Power LED Module 개발하기 위하여, 1W 백색(단색) LED 1EA LED Module과 1W 백색(단색) LED 3EA LED Module, 3W RGB LED 1EA LED Module에 대한 3종의 제품 개발하고, 고효율 RGB LED SMPS 회로 설계, 광색 가변을 위한 RGB LED 최적 배치 및 렌즈 설계, 고출력 1W LED Module 방열 설계 및 기구 개발, SMPS 회로 및 RGB LED 배열 회로 통합 시제품 직접 제작하였다, 신뢰성 평가 및 성능 시험 등을 실시하였으며, T자형 Channel letter에 기존 고휘도 LED Module과 개발된 고출력 LED Nodule을 동시에 적용한 결과, 기존 고휘도 LED Module를 사용하였을 경우에는 $1W{\times}10$개로 10W의 전력을 소비하였으나 개발된 고출력 LED Nodule은 $3W{\times}3$개로 9W의 전력을 소비하였으며 1W의 에너지가 절감되었음에도 불구하고 평균 휘도는 약 2.5배, 균제도는 1.43 배가 더 우수한 결과를 얻었다.

The paper is to evaluate for reliability of LED Channel Modules by ALTs(Accelerated Life Tests). The recently, some of KS were established by law of LED Lamps for Lighting(KS C 7651, KS C 7652 and KS C 7653), but reliability assessment methods of LED Channel Modules were not established. Therefore, the paper aided companies to test methods for accelerated life testing by themselves.

본 논문은 LED조명기구 방열설계의 열해석에 관한 것으로서 메탈 PCB에 Chip LED를 배치하여 COMSOL Multiphysics로 시뮬레이션한 결과 LED와 PCB의 경계면 온도는 약 $80^{\circ}C$이며, PCB의 바닥면까지는 약 $50^{\circ}C$까지 변화함을 검증 하였으며, 결과적으로 실 제작의 근사치에 가까운 방열설계가 가능함이 확인되었다.

In this paper, the optical properties of the 54[W] LED module have confirmed by changing the angles of LED modules for street light applications. The angle of LED module changed from the $0[^{\circ}]$ to $60[^{\circ}]$ varying by $20[^{\circ}]$ as horizontal direction ${\ominus}_1$. Morever, the angle of LED module changed from the $0[^{\circ}]$ to $15[^{\circ}]$ varying by $5[^{\circ}]$ as vertical direction ${\ominus}_2$. As a result of simulation, the average illumination was about 17[lux] and the overall illuminance uniformity was 0.29 for a 10.39[m] long and 6[m] wide illuminance area at height of 6[m], which is acceptable for street lighting illumination in the Illuminating Engineering Society(IES) standard.