• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2013년도 추계학술대회
• /
• pp.188-191
• /
• 2013

본 논문은 수직형 정수처리시설 내의 에너지 절감을 위해 외부의 자연광과 인체감지를 통한 실내 조도 제어용 LED 조명 제어보드를 구성하여 무선 환경에서의 실시간 모니터링을 통해 조명 제어가 가능하도록 구성하였다. 또한, Zigbee 통신을 LED 조명에 적용함으로서 무선 데이터 전송과 능동적 LED 조명 밝기제어가 가능하도록 구성하였다. 제안한 제어방식은 외부의 자연광에 따라 조명의 밝기를 단계별로 디밍 제어하여 조절 및 제어함으로써 실내에너지를 실시간으로 제어하여 에너지 절약 효과를 극대화할 수 있다.

• 제어로봇시스템학회논문지
• /
• 제21권4호
• /
• pp.309-314
• /
• 2015

In this study, an embedded ranging system based on a laser structured light image is developed. The distance measurement by the structured light image processing has efficient computation because the burdensome correspondence problem is avoidable. In order to achieve robustness against environmental illumination noise and real-time laser structured light image processing, a bandpass optical filter is adopted in this study. The proposed ranging system has an embedded image processor performing the whole image processing and distance measurement, and so reduces the computational burden in the main control system. A system calibration algorithm is presented to compensate for the lens distortion.

• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2007년도 추계학술대회 논문집
• /
• pp.179-182
• /
• 2007

현재 우리나라 대부분의 사무실 및 학교교실에는 형광등 스위치가 창측, 중간, 복도측등으로 회로가 분리되어 있으나 날씨가 맑고 태양빛이 많이 비치는 경우(기준조도 이상)에도 창측의 형광등이 항상 켜져 있는 경우가 대부분이므로 외부 쪽 창측에 설치되는 형광등기구에 외부광량(일조량)에 따라 자동으로 ON, OFF되는 센서가 부착된 형광등기구를 사용하여 에너지가 절감될 수 있는 방안을 연구하고 자한다.

• 센서학회지
• /
• 제25권3호
• /
• pp.189-195
• /
• 2016

In this paper, we newly introduce a visible light communication (VLC) repeater using the LED array in an LED lamp. The LED array is used for a light source in the repeater, which radiates light both for illumination and data transmission. A VLC repeater is made by adding some electronic circuits to the LED array including a photodetector, a demodulator, and a modulator. The repeater is installed on the ceiling of a room like a conventional LED lamp, receives the VLC signal from an arbitrary transmitter, recovers data, and radiates the signal to wide area in the room. We used a carrier frequency of 100 kHz for the uplink from a transmitter to the repeater, and 500 kHz for the downlink from the repeater to a receiver. The repeater is useful for increasing the transmission path to wide area over the obstacles that may exist between VLC transmitters and receivers.

• Journal of Advanced Marine Engineering and Technology
• /
• 제38권2호
• /
• pp.169-174
• /
• 2014

This paper proposes a novel beehive-shaped reflector for application to light-emitting diode (LED) transceivers for illumination and bi-directional visible light communication (VLC). By using a diffuse propagation model extended to line-of-sight and direct signals, the distribution of illuminance and the path loss of the transceiver are investigated to evaluate the performance of the beehive-shaped reflector. To verify bi-directional communication, a VLC-based image capture system, comprising a complementary metal-oxide semiconductor (CMOS) image sensor and video processor unit, is demonstrated. Real-time images captured by the CMOS camera are successfully transmitted to the monitoring system via a free-space channel at a rate of 115.2 kbps.

• 한국광학회지
• /
• 제32권2호
• /
• pp.68-78
• /
• 2021

측면 360° 조명을 위한 6개의 LED (light emitting diode)로 구성된 조명계가 부착된 캡슐내시경용 초소형 반사굴절식 전방위 광학계를 설계하고 성능을 평가하였다. 이 광학계의 총 길이, 전장길이, 반화각(HFOV: half field of view), F-수는 각각 14.3 mm, 8.93 mm, 51°~120°, 3.5로 설계되었다. 이 전방위 광학계는 0.1 megapixels의 CMOS (complementary metal-oxide-semiconductor) 센서를 사용하였으며, LED 조명계는 한 개당 0.25 lm의 LED 6개를 사용하여 광축을 따라 놓여 있는 내장의 내벽을 조명하도록 하였다. 이 결과, 최적화 설계된 광학계의 변조전달함수 0.3에서의 공간주파수, 나이퀴스트 주파수인 44 lp/mm와 0.3의 변조전달함수에서 공차에 따른 누적확률, 초점심도는 각각 130 lp/mm, 95%, -0.097 mm~+0.076 mm이다. 또한 광학계의 시야각 범위 내에서 LED 조명계에 의한 광축으로부터 물체거리가 15 mm인 내장의 내벽에서의 시뮬레이션된 조도는 최소 315 lx~최대 725 lx로 내장의 내벽을 촬영할 수 있는 조도와 가시도임을 알 수 있다.

• 전기학회논문지
• /
• 제64권12호
• /
• pp.1761-1767
• /
• 2015

This paper deals with the solar tracking performance using a small heliostat, the light reduction rate of the sun light, and the performance of uniform irradiation of LED light for a plant factory. A high precision encoder is attached to the heliostat to improve tracking accuracy. As a result, our heliostat-based solar tracking systems track efficiently the movement of the sun light in experimental tests. The reduction rate of the sun light in the plant factory is then measured by using an illumination sensor. The average reduction rate is 4.29%, which represents lower light reduction rates. In uniform irradiation tests of LED light, sixteen points are measured, and overall deviations of irradiation were within eight percents.

• 조명전기설비학회논문지
• /
• 제29권2호
• /
• pp.1-7
• /
• 2015

The Light Emitting Diode(LED) lighting control system proposed in this thesis is made up of a sensor module, a microcontroller, Bluetooth wireless communication, LED Driver, and LED downlight. The sensor module, comprised of an infrared sensor, an illumination sensor, and a temperature sensor, was designed to one Printed Circuit board(PCB). The system is able to identify the environment information collected by the sensor, and make it possible to control lighting automatically and manually through sensors. In addition, depending on users' conditions, a color temperature can be controlled. CS-1000, a spectroradiometer, was employed to measure the changing values of a color temperature in 8 steps. According to a test, it was found that it was possible to change a color temperature from 3187K of Warm White LED to 5598K of Cool White LED. The Bluetooth based wireless communication technique makes it possible to control more lighting devices than other wireless communication techniques does.

• Current Optics and Photonics
• /
• 제5권3호
• /
• pp.298-305
• /
• 2021

Modern distance sensing methods employ various measurement principles, including triangulation, time-of-flight, confocal, interferometric and frequency comb. Among them, the triangulation method, with a laser light source and an image sensor, is widely used in low-cost applications. We developed an omnidirectional two-dimensional (2D) distance sensor based on the triangulation principle for indoor floor mapping applications. The sensor has a range of 150-1500 mm with a relative resolution better than 4% over the range and 1% at 1 meter distance. It rotationally scans a compact one-dimensional (1D) distance sensor, composed of a near infrared (NIR) laser diode, a folding mirror, an imaging lens, and an image detector. We designed the sensor layout and configuration to satisfy the required measurement range and resolution, selecting easily available components in a special effort to reduce cost. We built a prototype and tested it with seven representative indoor wall specimens (white wallpaper, gray wallpaper, black wallpaper, furniture wood, black leather, brown leather, and white plastic) in a typical indoor illuminated condition, 200 lux, on a floor under ceiling mounted fluorescent lamps. We confirmed the proposed sensor provided reliable distance reading of all the specimens over the required measurement range (150-1500 mm) with a measurement resolution of 4% overall and 1% at 1 meter, regardless of illumination conditions.

• 한국인터넷방송통신학회논문지
• /
• 제14권6호
• /
• pp.207-213
• /
• 2014

본 논문에서는 블루투스 기반의 효율적인 실내 감성조명 제어 시스템을 제안한다. 제안된 블루투스 기반의 실내 감성조명 제어 시스템은 블루투스 모듈을 이용해 모바일이나 PC, 월 패드로 점등제어 할 수 있으며, 모션 센서로 자동 점등제어가 가능하게 설계하였다. 또한, 온도, 습도, 조도, 모션 센서로 외부환경에 따라 LED 점 소동을 제어하고, 움직임 미감지시에는 패턴을 이용하여 점등제어하게 설계하였다. 시스템은 블루투스 기반으로 조명 센서를 사용하고, 원하는 조명 제어를 선택하여 자동 제어 할 수 있다. 제안하는 실내 감성조명 제어 시스템의 효율성 검증 결과 기존 단순 On/Off의 제어 시스템보다 전력 소비를 감소시켰고, 에너지 절감 효과를 극대화 할 수 있었으며, 거주자에게 적합하게 내부 환경을 제공할 수 있도록 설계하였다.