• Annual Conference of KIPS
• /
• 2024.05a
• /
• pp.546-547
• /
• 2024

의료용 헬스케어 데이터를 기반으로 혈당, 혈압, 온도와 같은 헬스케어 의료기기 개발에서 정확하고 정밀도가 높은 결과를 얻기 위해 다기능의 센서들이 집적화 되고 있다. 그러나 이러한 헬스케어용 의료기기들은 24 시간 구동하기 때문에 전력소모가 크므로 실시간 모니터링이 필요하다. 본 논문은 웨어러블 센서에 보조전력 구동을 위한 유연태양전지의 전기적 및 광학적 데이터 분석을 통해 향후 헬스케어 디바이스 장치 구동을 위한 고효율의 태양전지를 전원보조장치로 활용하고자 한다.

• Korean Journal of Optics and Photonics
• /
• v.18 no.2
• /
• pp.111-116
• /
• 2007

A high power LED which is being used in many illumination applications as a new light source was simulated for its physical structure and then its optical properties were analyzed. To obtain accurate results from the designed LED model, properties of the die chip and reflector cup were varied. As a result, a high power LED model which has a radiation pattern of a Lambertian with its viewing angle of approximately $140^{\circ}$ and total included angle of $160^{\circ}$ was designed.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.08a
• /
• pp.326-326
• /
• 2012

ZnO와 GaN는 비슷한 특성을 가지고 있다. 즉, 상온에서 ZnO의 밴드갭은 3.36 eV이며 GaN은 3.39 eV이고, 두 물질 모두 Wurzite 구조이며, 격자상수 또한 비슷하다. 밴드갭 에너지가 매우 큰 GaN와 ZnO는 청색 또는 자외선 영역의 발광 또는 수광 소자의 응용성을 가지고 있다. 특히, ZnO는 exciton binding energy가 상온에서 60 meV로 매우 큰 편이기 때문에 상온에서 발광소자로서 안정성을 보장할 수 있어서 발광소자나 광측정 장치 등에 응용이 기대되고 있다. 이러한 장점에도 불구하고 n-ZnO/p-GaN 이종접합 구조에 대한 연구가 아직까지 미미한 상태이다. 본 연구에서는 UHV 스퍼터링 장치로 상온에서 형성한 n-ZnO/p-GaN 이종접합 다이오드 구조에 대한 전기적 및 광학적 물성을 분석하였다. 먼저 p형 GaN 기판 위에 ZnO 박막을 증착한 후에, ZnO 박막의 결정성을 개선시키기 위해 rapid thermal annealing 시스템을 이용하여400, 500, $600^{\circ}C$에서 각각 1분 동안 후 열처리를 실시하였다. 이때 $600^{\circ}C$에서 후 열처리한 ZnO박막은 $5{\times}10^{16}cm^{-3}$인 n형으로 나타났다. n-ZnO/p-GaN 이종접합 다이오드구조에 대한 I-V 및 photoluminescence 측정 등을 통해 전기적 및 광학적 특성을 분석하였다.

• Journal of the Korean Institute of Telematics and Electronics T
• /
• v.35T no.1
• /
• pp.40-47
• /
• 1998

The optical heads as the key parts of digital audio/video players are applied extensively from general household electric appliances to computer memory or game apparatuses, and the demand of them tends to be increased according to the extension of optical medium market. In this paper, the 2-axis actuator, the key component for focus servo and tracking servo of the optical head is designed as a type of the cantilever suspended by 4 wires. The design propriety is verified through its simulation and the characteristic analysis of its mock-ups. The other factors which influence the performance of 2-axis actuators besides the design factors of them, are also verified through the mock-up analysis.

• Korean Journal of Optics and Photonics
• /
• v.16 no.5
• /
• pp.462-468
• /
• 2005

The bit type holographic data storage is known to have many advantages in instrumentation for its compactness and simplicity, when compared to the 2-D page type holographic data storage. But it requires various multiplexing method for one bit hologram to achieve high storage densities. We propose an optical architecture for bit type holographic data storage which utilizes peristrophic and angular multiplexing simultaneously. Selectivity and characterization are analyzed for the proposed architecture. The possible number of multiplexing(72 bit holograms) and maximum storage densities calculation is confirmed experimentally.

• Clean Technology
• /
• v.16 no.4
• /
• pp.265-271
• /
• 2010

The deactivated diesel oxidation catalyst(DOC) was remanufactured by ultrasonic wave treatment with various solutions, followed by active component re-impregnation. The catalytic performance and surface properties of remanufactured DOC were studied at various remanufacturing conditions. The proper ultrasonic-wave cleaning time at various solutions and optimal re-impregnation amounts of active component for the best catalytic performance were investigated. The catalytic performance tests on the conversions of CO and THC(total hydrocarbon) were also carried out at various temperatures by catalytic reaction test unit using bypass gas from the diesel engine dynamo system. It was found that the catalytic performance of DOC remanufactured with the high-temperature air washing, ultrasonic wave cleaning at acidic/basic solutions and active component re-impregnation method was recovered to 90% level of its activity compared to that of the fresh DOC, which was caused by removing the deactivating materials from the surface of the DOC through the analyses of catalyst performance test and their characterization by Optical microscope, EDX, ICP, TGA, and porosimeter.

• Korean Journal of Optics and Photonics
• /
• v.35 no.5
• /
• pp.235-240
• /
• 2024

Since the coronavirus pandemic, research and application of space sterilization effects using UV light sources have been rapidly increasing. In this paper, the space-sterilization effect of UV LED light sources that can be built into indoor environmental systems or lighting devices is quantitatively analyzed through an illumination optical approach. Through this, it is possible to establish a foundation for optimizing the sterilization effect in indoor spaces in the 275±5 nm wavelength range, which is known to have excellent space-sterilization power.

• Journal of the Korean Society of Radiology
• /
• v.6 no.6
• /
• pp.477-481
• /
• 2012

An X-ray diffractometer which has various X-ray optics can give qualitative and quantitative information for a sample using a nondestructive analysis method. A parallel beam optic passes the parallel beam and removes divergent beam generated from an X-ray tube. The parallel beam optic used in the X-ray diffractometer was fabricated by wire cut and grading of stainless steel plates and was evaluated its performance using an X-ray imaging system. The measured parallelization of 6.6 mrad for the fabricated the parallel beam optic was a very close to the expected value of 6 mrad. An X-ray imaging technique for evaluating the parallel beam optics can estimate parallelization for each plate and can be used to other X-ray optics.

• Korean Journal of Optics and Photonics
• /
• v.7 no.1
• /
• pp.1-8
• /
• 1996

Charge-coupled device(CCD) array detectors are widely used in real time modulation transfer function(MTF) measurement systems. This paper presents the characteristics of two-dimensional CCDs used in a real time MTF measurement system for copy lenses. The MTF characteristics of a copy lens measured by this equipment show different results according to the direction of shift register, shutter speed and the amplifier gain of CCDs. An object generator is fabricated to reduce the variation of MTF values for the irradiance nonuniformity in on-axis and off-axis image plane and this MTF equipment is calibrated by using a standard lens.

• Proceedings of the Optical Society of Korea Conference
• /
• 2001.02a
• /
• pp.200-201
• /
• 2001

헬멧 장착형 HMD(Head-Mounted Display) 시스템은 비행기 조종사나 저격수의 시선을 크게 움직이지 않고 군사 전술상의 현재 상태를 볼 수 있도록 하여 눈의 피로감을 줄이고 시선의 이동에 의한 돌발적인 사고의 위험을 감소시킬 수 있어 군사적으로 유용한 장치이다 HOE(Holographic Optical Element)의 중요한 응용 분야 중 하나로 HMD에서의 결상 렌즈 또는 광 결합기가 있다 HMD 시스템에서 HOE의 역할은 2차원의 단색 디스플레이 영상을 헬멧 착용자의 눈에 반사하여 결상시키는 것이다. (중략)