• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.693-698
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• 2016

Bruise caused by damages through physical compression and suction is one of evidences that can prove abuse or assault. It is essential for taking photography to prove a crime. Some studies about the Infrared (IR) light source have limitations that only one IR light source and one barrier filter were used. To find the best combination of filters and IR light sources, we produced suction bruise artificially and used three IR light sources and five barrier filters. Consequently, we found that the best combination is using a tungsten lamp and Kodak Wratten #18A barrier filter.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.205-215
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• 2011

Films are sensitive to ultraviolet rays and in contrast, digital camera sensors are extremely sensitive to infrared rays due to the differences in spectral characteristics. As a result, all digital cameras that use CCD or CMOS are equipped with IR Cut-Off Filter on the overall sensor. Complete block out of infrared rays is ideal, but the actual experiment results showed that infrared rays were not being blocked out completely. Infrared permeability was also different for each camera. Therefore, this study aims to analyze the effect of the minute quantities of infrared rays, which get transmitted due to mechanical properties of IR Cut-Off Filters that are installed on digital cameras, on digital picture images. The results obtained by carrying out a comparative analysis of a UV Filter (infrared transmitting state) and a UV-IR Filter (infrared blocked out state) are as follows. It was confirmed that the minute quantities of infrared rays do affect dynamic range and resolution to some extent, despite the little or no difference in noise and color reproduction.

• Korean Journal of Optics and Photonics
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• v.17 no.5
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• pp.480-486
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• 2006

Generally, IR cut-off filters for mobile phone is coated on the glass substrate at high temperature(above $300^{\circ}C$). In this work, we prepared IR cut-off filters on the poly(methyl methacrylate)(PMMA) substrates at low temperature(about $70^{\circ}C$ ). using the $CeO_2\;and\;SiO_2$ coatings by physical vapor deposition. The surface energies of coated and uncoated PMMA, and adhesive properties of IR cut-off filters coatings were examined using contact angle measurements. We demonstrate the improve of mobile phone optical system using these results.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.642-645
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• 2012

본 논문에서는 자외선 및 적외선 필터를 기반으로 불이 연소하면서 에너지를 빛과 열의 형태로 방출하는 산화 과정으로 여러 가지의 연소반응에 의해 표출 형태가 열, 전기, 연소가스, 복사 등으로 나타날 때, 이중 열복사로 빛이 방출되는 화염의 온도에 따라 각각 특성이 다른 파장을 활용한 적외선과 자외선(IR/UV) 필터를 활용한 불꽃영상 감지시스템 설계방안을 제안한다.

• Journal of Digital Contents Society
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• v.13 no.3
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• pp.271-278
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• 2012

Recently, infrared (IR)-based depth sensors have proliferated as consumer electronics thanks to decreased price, which led to various applications including gesture recognition in television virtual studios. However, the depth sensors fail to capture depth information correctly under strong light conditions emitting infrared light which are very common in television studios. This paper analyzes the mechanism of such interference between the depth sensors relying on certain IR frequencies and infrared light emitting sources, and provides methods to get correct depth information by applying filters. Also, it describes experiment methods and presents the results of applying multiple combinations of filters with different cut-off frequencies. Finally, it proves that the interference due to IR can be filtered out using proposed filtering method practically by experiment.

• Korean Journal of Optics and Photonics
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• v.35 no.1
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• pp.24-29
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• 2024

We propose a hyperbolic metastructure based on a nanopatterned metal (Ag)-dielectric (PDMS) multilayer and report on its performance in an infrared (IR) cut-off filter for imaging devices. By optimizing the size of the square-shaped Ag nanopattern and the thickness of PDMS surrounding the Ag nanopattern, the proposed IR cut-off filter blocks 99% of light in the 0.70-1.01 ㎛ wavelength band while maintaining a high transmittance of over 94% in the visible region. Here, the cut-off wavelength band starts at a region above the epsilon-near-zero wavelength of the hyperbolic metastructure and ends at the point where plasmonic absorption appears strongly. It is observed that transmittance in the wavelength region longer than the IR cut-off band increases again due to plasmonic coupling among horizontally adjacent Ag nanopatterns. This metastructure can improve the performance of IR-blocking filters as well as allow it to be manufactured ultra-thin, which is applicable to various planar optical elements and integrated optical components.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.337-337
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• 2009

가시광선영역에서 매우 균일한 높은 투과성뿐만 아니라 근적외선영역에서 가파른 홉수성 엣지와 함께 낮은 투과율을 제공하는 산화구리(II)를 함유하는 포스페이트 유리는 컬러 비디오 카메라의 컬러 보정 필터, 발광 컬러 디스플레이용 보호판(sheild), 모노크로메이터의 미광 필터, 플라스틱 복합재 필터의 무기 성분 및 CCD(전하 결합 소자) 및 CMOS(상보성 금속 산화물 반도체) 카메라 및 검출기 분야용 필터 유리로서 사용된다. 용융온도 및 산화구리(II) 첨가량에 따른 투과율을 측정하기 위해 포스페이트 유리 시료를 $1100\sim1500^{\circ}C$ 용융한 후 $400^{\circ}C$에서 2시간 동안 어닐링 공정을 거쳐 제조하였다. 제조된 시료는 두께 0.3mm로 폴리싱하여 자외선-적외선 분광 광도기를 이용하여 광학적 특성을 측정하였다. 본 실험을 통하여 용융온도에 따라 가시광선영역 및 근적외선영역에서의 투과율 거동을 비교한 결과 $1100\sim1200^{\circ}C$에서의 우수한 투과율 특성을 나타냈다. 용융온도가 내려감에 따른 가시광선영역 (400~600nm)에서 높은 투과율 및 근적외선영역 (750~1100nm)에서 낮은 투과율과 가파른 흡수성 엣지를 나타냈다.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.11
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• pp.18-23
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• 2002

고품질의 극저온 환경의 생성 및 유지는 고품질 대용량 정보통신, 의료진단, 초전도 및 고집적반도체 제조공정 등의 차세대 유망 산업 분야에서 필수적인 요소로 자리 잡고 있으며, cryopump, 민수용 및 군수용의 적외선 검지기 및 초전도 RF 필터의 효과적 냉각을 위해 보다 높은 신뢰성과 수명, 고효율의 극저온 냉동기에 대한 수요는 점차 증대될 것으로 기대된다. 스터링 냉동기 및 맥동관 냉동기는 짧은 역사에도 불구하고, 다양한 분야에서 기존의 한제 및 극저온 냉동기를 대치하여 활용될 수 있을 것으로 전망된다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.3
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• pp.219-229
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• 2018

This paper proposes Kalman Filter-based relative navigation algorithms for proximity tasks such as rendezvous/docking/cluster-operation of spacecraft using PSD Sensors and Infrared Beacon Modules. Numerical simulations are performed for comparative analysis of the performance of each relative-navigation technique. Based on the operation principle and optical modeling of the PSD Sensor and the Infrared Beacon Module used in the relative navigation algorithm, a measurement model for the Kalman filter is constructed. The Extended Kalman Filter(EKF) and the Unscented Kalman Filter(UKF) are used as probabilistic relative navigation based on measurement fusion to utilize kinematics and dynamics information on translational and rotation motions of satellites. Relative position and relative attitude estimation performance of two filters is compared. Especially, through the simulation of various scenarios, performance changes are also investigated depending on the number of PSD Sensors and IR Beacons in target and chaser satellites.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3127-3129
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• 2000

본 논문에서는 광 다이오드에서 들어오는 신호로부터 원하는 대역의 신호를 얻기 위한 적외선 수신 IC에 적합한 대역통과필터를 설계하였다 설계한 대역통과필터는 2차 Biquad gm-C 필터의 구조를 이용하여 중심주파수가 38kHz. Quality factor가 10인 필터를 구현하였다. 구현된 대역통과필터는 필터부분과 중심주파수를 보정해 주는 frequency tuning 부분으로 구성되어 있다. 낮은 transconductance와 높은 선형성을 요구하는 transconductor의 설계를 위해 Gilbert 곱셈기 특성을 이용하여 구현하였고 AMS사의 0.8${\mu}m$ BiCMOS model을 사용하여 +5V로 동작되도록 설계 하였다