• Title/Summary/Keyword: IR Light

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Black Body Design and Verification for Non-Uniformity Correction of Imaging Sensor and Uncertainty Analysis (영상센서의 비균일 응답특성 보정을 위한 흑체 설계 및 성능검증과 보정오차 분석)

  • Shin, Somin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.3
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    • pp.240-245
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    • 2013
  • Each pixel of InfraRed(IR) sensor differently responds to IR light as time elapses or the sensor on/off operation is repeated. As a result, the quality of IR sensor image is deteriorated, and therefore NUC(Non-uniformity Correction) is periodically needed for IR sensor. In this paper, in order to perform NUC in the Satellite, on-board V-grooved blackbody is designed with a baffle so that the emissivity of black body is to be higher than 0.995 as well as the temperature deviation is less than $1^{\circ}C$ in the range of the infrared wave length from 3.3 to $5.2{\mu}m$. To check its performance, the emissivity and the surface temperature of the blackbody by TRT(Transfer Reference Thermometer) and IR Micrometer scanner are measured, respectively. From the results, black body design is verified and the uncertainty of NUC is estimated through the measurement results.

Highly Efficient Red Emissive Heteroleptic Cyclometalated Iridium(III) Complexes Bearing Two Substituted 2-Phenylquinoxaline and One 2-Pyrazinecarboxylic Acid

  • Sengottuvelan, Nallathambi;Yun, Seong-Jae;Kim, Dae-Young;Hwang, In-Hye;Kang, Sung Kwon;Kim, Young-Inn
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.167-173
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    • 2013
  • A series of highly efficient red phosphorescent heteroleptic iridium(III) complexes 1-6 containing two cyclometalating 2-(2,4-substitued phenyl)quinoxaline ligands and one chromophoric ancillary ligand were synthesized: (pqx)$_2Ir$(mprz) (1), (dmpqx)$_2Ir$(mprz) (2), (dfpqx)$_2Ir$(mprz) (3), (pqx)$_2Ir$(prz) (4), (dmpqx)$_2Ir$(prz) (5), (dfpqx)$_2Ir$(prz) (6), where pqx = 2-phenylquinoxaline, dfpqx = 2-(2,4-diflourophenyl)quinoxaline, dmpqx = 2-(2,4-dimethoxyphenyl)quinoxaline, prz = 2-pyrazinecarboxylate and mprz = 5-methyl-2-pyrazinecarboxylate. The absorption, emission, electrochemical and thermal properties of the complexes were evaluated for potential applications to organic light-emitting diodes (OLEDs). The structure of complex 2 was also determined by single-crystal X-ray diffraction analysis. Complex 2 exhibited distorted octahedral geometry around the iridium metal ion, for which 2-(2,4-dimethoxyphenyl)quinoxaline N atoms and C atoms of orthometalated phenyl groups are located at the mutual trans and cis-positions, respectively. The emission spectra of the complexes are governed largely by the nature of the cyclometalating ligand, and the phosphorescent peak wavelengths can be tuned from 588 to 630 nm with high quantum efficiencies of 0.64 to 0.86. Cyclic voltammetry revealed irreversible metal-centered oxidation with potentials in the range of 1.16 to 1.89 V as well as two quasi-reversible reduction waves with potentials ranging from -0.94 to -1.54 V due to the sequential addition of two electrons to the more electron-accepting heterocyclic portion of two distinctive cyclometalated C^N ligands.

Performance Evaluation of Mid-IR Spectrometers by Using a Mid-IR Tunable Optical Parametric Oscillator (중적외선 광 파라메트릭 발진기를 이용한 중적외선 분광기 성능 평가)

  • Nam, Hee Jin;Kim, Seung Kwan;Bae, In-Ho;Choi, Young-Jun;Ko, Jae-Hyeon
    • Korean Journal of Optics and Photonics
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    • v.30 no.4
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    • pp.154-158
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    • 2019
  • We have used a mid-IR (mid-infrared) continuous-wave (cw) optical parametric oscillator (OPO), developed previously and described in Ref. 12, to build a performance-evaluation setup for a mid-IR spectrometer. The used CW OPO had a wavelength tuning range of $ 2.5-3.6{\mu}m$ using a pump laser with a wavelength of 1064 nm and a fan-out MgO-doped periodically poled lithium niobate (MgO:PPLN) nonlinear crystal in a concentric cavity design. The OPO was combined with a near-IR integrating sphere and a Fourier-transform IR optical spectrum analyzer to build a performance-evaluation setup for mid-IR spectrometers. We applied this performance-evaluation setup to evaluating a mid-IR spectrometer developed domestically, and demonstrated the capability of evaluating the performance, such as spectral resolution, signal-to-noise ratio, spectral stray light, and so on, based on this setup.

Synthesis of 6-Alkyl-3-Chromonealdehyde(2,2-dialkyl)hydrazone Derivatives for Green Light Emitting Materials (녹색발광 6-알킬-3-크로몬알데히드(2,2-디알킬)하이드라존 유도체의 합성)

  • Chung, Pyung-Jin;Chang, Hong-Joon
    • Applied Chemistry for Engineering
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    • v.21 no.4
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    • pp.424-429
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    • 2010
  • 6-Alkyl-3-chromonealdehyde (2,2-dialkyl)hydrazone derivatives were synthesized by dehydration condensation. They are green-emitting materials for organic light emitting device (OLED) composed of electron acceptor of 6-alkyl-3-chromonealdehydes and electron donor of 2,2-dialkylhydrazones in a conjugated structure. The structural properties of reaction products were analyzed by FT-IR and $^1H$-NMR spectroscopy. The thermal stabilities and reactivities were measured by melting points and yields. The UV-visibles and PL properties were also determined by excitation spectra and emission spectra, respectively.

Real-Time Eye Detection and Tracking Under Various Light Conditions

  • Park Ho Sik;Nam Kee Hwan;Seol Jeung Bo;Cho Hyeon Seob;Ra Sang Dong;Bae Cheol Soo
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.862-866
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    • 2004
  • Non-intrusive methods based on active remote IR illumination for eye tracking is important for many applications of vision-based man-machine interaction. One problem that has plagued those methods is their sensitivity to lighting condition change. This tends to significantly limit their scope of application. In this paper, we present a new real-time eye detection and tracking methodology that works under variable and realistic lighting conditions. Based on combining the bright-pupil effect resulted from IR light and the conventional appearance-based object recognition technique, our method can robustly track eyes when the pupils are not very bright due to significant external illumination interferences. The appearance model is incorporated in both eyes detection and tracking via the use of support vector machine and the mean shift tracking. Additional improvement is achieved from modifying the image acquisition apparatus including the illuminator and the camera.

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The Color Matching Algorithm in Near Infrared Range for Military Camouflage (IR영역에서의 위장염색을 위한 칼라 매칭 알고리즘 연구)

  • Song Kyung-Hun;Yuk Jong-Il;Ha Hun-Seung;Lee Tae-Sang;You Young-Eun;Lee Si-Woo
    • Textile Coloration and Finishing
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    • v.17 no.4 s.83
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    • pp.7-14
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    • 2005
  • The purpose of this study was to develop the color matching program with the excellent camouflage capacity in the near infrared range($\~$1100nm) including the visible light range for cotton fabrics. It was measured IR spectral reflectance in the range of $380\~1,100nm$ after dyed with vat dyes, and we made database for reflectance with various concentration on vat dyes which have a low reflectance value in the infrared range. The color matching algorithm that could be simulated in both the human visible light and the near infrared range was constructed by numerical analysis method using the database. In this study we also developed the dyeing conditions and dyeing process through the continuous-dyeing experiment with the vat dyes for cotton fabrics.

Synthesis of 3-Chromonealdehyde(2,2-disubstituted)hydrazone Derivatives for Green Light Emitting Materials (녹색발광 3-크로몬알데히드(2,2-이치환)하이드라존 유도체의 합성)

  • Chung, Pyung Jin;Chang, Hong Joon
    • Applied Chemistry for Engineering
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    • v.20 no.6
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    • pp.670-674
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    • 2009
  • 3-Chromonealdehyde(2,2-disubstituted)hydrazone derivatives were synthesized by dehydration condensation. They are green-emitting materials for organic light emitting device (OLED) composed of electron acceptor of 3-chromonealdehydes and electron donor of 2,2-disubstituted hydrazones by a conjugated structure. The structural properties of reaction products were analyzed FT-IR and $^1H-NMR$ spectroscopy. The thermal stabilities and reactivities were measured by melting points and yields. The UV-visibles and PL properties can be determined by excitation spectra and emission spectra, respectively.

Real-Time Eye Detection and Tracking Under Various Light Conditions (다양한 조명하에서 실시간 눈 검출 및 추적)

  • 박호식;배철수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.2
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    • pp.456-463
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    • 2004
  • Non-intrusive methods based on active remote IR illumination for eye tracking is important for many applications of vision-based man-machine interaction. One problem that has plagued those methods is their sensitivity to lighting condition change. This tends to significantly limit their scope of application. In this paper, we present a new real-time eye detection and tacking methodology that works under variable and realistic lighting conditions. Based on combining the bright-Pupil effect resulted from IR light and the conventional appearance-based object recognition technique, our method can robustly track eyes when the pupils ale not very bright due to significant external illumination interferences. The appearance model is incorporated in both eyes detection and tacking via the use of support vector machine and the mean shift tracking. Additional improvement is achieved from modifying the image acquisition apparatus including the illuminator and the camera.

Study on the Characteristics and Fabrication of Organic Light Emitting Devices Using the Synthesised Phosphorescent Metal Complexes (인광특성이 있는 금속 착물의 합성과 그 물질을 이용한 소자 제작 및 소자 특성 평가)

  • Kim, Young-Kwan;Sohn, Byoung-Chung;Kim, Jun-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.19 no.2
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    • pp.97-102
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    • 2002
  • Recently, the phosphorescent organic light-emitting devices (OLEDs) have been extensively studied for their high internal quantum efficiency. In this study, we synthesised several phosphorescent metal complexes, and certified their composition using NMR. We also investigated the characteristics of the phosphorescent OLEDs with the green emitting phosphor, $Ir(ppy)_{3}$. The devices with a structure of indium-tin-oxide(ITO)/N,N'-diphenyl-N,N'-(3-methylphenyI}-1,1'-biphenyl-4,4'-diamine (TPD)/metal complex doped in host materials/2,9-dimethyl-4,7-diphenyl-l,10-phenanthroline(BCP)/tris (8-hydroxyquinolinato) Aluminum($Alq_{3}$)/Li:Al/Al was fabricated, and its electrical and optical characteristics were studied. By changing the doping concentration of tris(2-phenylpyridine)iridium ($Ir(ppy)_{3}$), we fabricated several devices and investigated their characteristics.

A Wearable Watch-type Reflectance-based Blood-oxygen Saturation (SpO2) Level Estimation (반사광을 이용한 손목시계형 혈중산소포화도 (SpO2) 측정기)

  • Lee, Hooseok;Thap, Tharoeun;Lee, Jinseok
    • Proceedings of the Korea Information Processing Society Conference
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    • 2015.10a
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    • pp.578-579
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    • 2015
  • Transmission and reflectance are two non-invasive techniques to perform pulse oximetry. This paper presents a design of reflectance-based pulse oximetry for watch-type wearable device, in which sensor and detector are located on the same surface of the body part. The basic principle of a pulse oximeter is based on the measurement of the red and infrared (IR) light absorption. Oxygenated blood has significant differences of light absorption characteristics than deoxygenated blood under red (660 nm) and infrared (940 nm) wavelength. Infrared is absorbed more by oxygenated hemoglobin than red. So the hardware implementation is included placing of the two LEDs (red and IR) with single photo-detector in the middle on the patient's wrist to get the corresponding pulsatile signals which are used to estimate the $SpO_2$.