• Title/Summary/Keyword: blackbody radiation

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Size-of-source Effect and Self-radiation Effect of an Infrared Radiation Thermometer (적외선 복사온도계의 복사원 크기효과 및 자기복사효과)

  • Yoo, Yong-Shim;Kim, Bong-Hwak;Park, Chul-Woung;Park, Seung-Nam
    • Korean Journal of Optics and Photonics
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    • v.21 no.4
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    • pp.133-138
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    • 2010
  • All radiation thermometers have a size-of-source effect (SSE) and a self-radiation effect (SRE). The SSE,defined as dependence of the detector signal of a radiation thermometer on the diameter of a source, is critically dependent on the wavelength since diffraction is the main cause. In this paper, we have measured the SSE and the SRE of TRT2 (Transfer Radiation Thermometer 2, HEITRONICS) widely used as a transfer standard in low and middle temperature range. At $300^{\circ}C$, The radiation temperature difference between the 60 mm diameter blackbody and 10 mm diameter blackbody due to the SSE was estimated to be $3.5^{\circ}C$ in low temperature mode ($8-14\;{\mu}m$) and $0.5^{\circ}C$ in middle temperature mode ($3.9\;{\mu}m$). In addition, the measured radiation temperature difference of the blackbody due to the SRE was found to be 110 mK when the body temperature change of TRT2 was set at $2.6^{\circ}C$.

Design and Performance Evaluation of Low-Temperature Vacuum Blackbody System (저온-진공 흑체시스템의 설계 및 성능 평가)

  • Kim, Ghiseok;Chang, Ki Soo;Lee, Sang-Yong;Kim, Geon-Hee;Kim, Dong-Ik
    • Journal of the Korean Society for Nondestructive Testing
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    • v.33 no.4
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    • pp.336-341
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    • 2013
  • In this paper, the design concept of a low-temperature vacuum blackbody was described, and thermophysical model of the blackbody was numerically evaluated. Also the working performance of low-temperature vacuum blackbody was evaluated using infrared camera system. The blackbody system was constructed to operate under high-vacuum conditions ($2.67{\times}10^{-2}$ Pa) to reduce temperature uncertainty, which is caused by vapor condensation at low temperatures usually below 273 K. In addition, both heat sink and heat shield including cold shield were installed around radiator to prevent heat loss from the blackbody. Simplified mathematical model of blackbody radiator was analyzed using modified Stefan-Boltzmann's rule. The infrared radiant performance of the blackbody was evaluated using infrared camera. Based on the results of measurements, and simulation, temperature stability of the low-temperature vacuum blackbody demonstrated that the blackbody system can serve as a highly stable reference source for the calibration of an infrared optical system.

Optical Characteristics of Bolometric Terahertz Sensor (볼로미터형 테라헤르츠 센서의 광학적 특성 연구)

  • Han, Myung Soo;Song, Woosub;Hong, Jung Taek;Lee, Donghee
    • Journal of Sensor Science and Technology
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    • v.27 no.5
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    • pp.335-339
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    • 2018
  • The optical characteristics of a terahertz (THz) antenna-coupled bolometer (ACB) detector were evaluated using a pulsed quantum cascade laser (QCL) and radiation blackbody sources. We investigated a method for measuring the responsivity and noise-equivalent power (NEP) of the THz detector using two different types of light sources. When using a QCL source with a frequency of 3 THz, the average responsivity of 24 devices was $1.44{\times}10^3V/W$ and the average NEP of those devices was $3.33{\times}10^{-9}W/{\surd}Hz$. The average responsivity and NEP as measured by blackbody source were $1.79{\times}10^5V/W$ and $6.51{\times}10^{-11}W/{\surd}Hz$, respectively, with the measured values varying depending on the light source. This was because the output power of each light source was different, with the laser source being driven by a pulse type wave and the blackbody source being driven by a continuous wave. The power input to the THz sensor was also different. Futhermore, the responsivity and NEP values measured using band pass filter (BPF) were similar to those measured when using only THz windows. It was found that ACB sensor responds normally in the THz region to both the laser and the blackbody source, and the method was confirmed to effectively evaluate the characteristics of the THz sensor.

A Variety of Activation Methods Employed in “Activated-Ion” Electron Capture Dissociation Mass Spectrometry: A Test against Bovine Ubiquitin 7+ Ions

  • Oh, Han-Bin;McLafferty, Fred W.
    • Bulletin of the Korean Chemical Society
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    • v.27 no.3
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    • pp.389-394
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    • 2006
  • Fragmentation efficiencies of various ‘activated-ion’ electron capture dissociation (AI-ECD) methods are compared for a model system of bovine ubiquitin 7+ cations. In AI-ECD studies, sufficient internal energy was given to protein cations prior to ECD application using IR laser radiation, collisions, blackbody radiation, or in-beam collisions, in turn. The added energy was utilized in increasing the population of the precursor ions with less intra-molecular noncovalent bonds or enhancing thermal fluctuations of the protein cations. Removal of noncovalent bonds resulted in extended structures, which are ECD friendly. Under their best conditions, a variety of activation methods showed a similar effectiveness in ECD fragmentation. In terms of the number of fragmented inter-residue bonds, IR laser/blackbody infrared radiation and ‘in-beam’ activation were almost equally efficient with ~70% sequence coverage, while collisions were less productive. In particular, ‘in-beam’ activation showed an excellent effectiveness in characterizing a pre-fractionated single kind of protein species. However, its inherent procedure did not allow for isolation of the protein cations of interest.

Establishment of Comparison Calibration Equipment for Infrared-radiation Thermometers Below ℃ (℃ 이하 적외선 복사온도계 비교 교정장치 구축)

  • Yoo, Yong Shim;Kim, Bong-Hak
    • Korean Journal of Optics and Photonics
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    • v.29 no.2
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    • pp.70-76
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    • 2018
  • Comparison calibration equipment for infrared-radiation thermometers below $0^{\circ}C$ has been established, using a TRT2 (transfer radiation thermometer 2, HEITRONICS) as a transfer standard and an ME30 (Model: ME30, HEITRONICS) as a variabletemperature blackbody. The TRT2 was calibrated using three fixed points (Ice ($0.01^{\circ}C$), In ($156.5985^{\circ}C$), and Sn ($231.928^{\circ}C$)) and the Planckian Sakuma-Hattori equation, and including the interpolation and extrapolation errors at $-50^{\circ}C$ in the uncertainty. The pneumatic lid is installed upon opening of the ME30 and is opened for only 30 seconds for measuring the radiation temperature, which prevents formation of ice in the ME30 and also reduces the calibration time to half. The farther away from the $0{\sim}232^{\circ}C$ region, the larger the uncertainty of the comparison calibration equipment becomes. The expanded uncertainty of the comparison calibration equipment was estimated as 0.26 K at $-20^{\circ}C$.

Construction and Measurement of Normal Spectral Emissivity Device using Fourier Transform Infrared Spectrometer (퓨리에 변환 적외선 분광기를 이용한 수직 분광 복사율 측정 장치의 제작과 측정)

  • Jeon, Sang-Ho;Yoo, Nam-Joon;Jo, Jae-Heung;Park, Chul-Woung;Park, Seung-Nam;Lee, Geun-Woo
    • Korean Journal of Optics and Photonics
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    • v.19 no.6
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    • pp.400-407
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    • 2008
  • An Instrument to measure normal spectral emissivity is built using a Fourier Transform-Infrared (FT-IR) spectrometer. The instrument is composed of four main parts, reference blackbody, sample furnace, optics system, and FT-IR spectrometer. Measurement ranges of temperature and wavelength are $200^{\circ}C{\sim}500^{\circ}C$ and $3.5{\mu}m{\sim}20{\mu}m$, respectively. Measured emissivity of the reference blackbody is greater than 0.9993 with combined relative uncertainty less than 0.69%, which can be considered an ideal blackbody. We studied the emissivity of opaque alumina, graphite, anodized aluminum, and steel (IMS 200). It is shown that emissivity increases with the roughness of the steel (IMS 200) surface.

Bubble Behavior and Radiation for Laser-Induced Collapsing Bubble in Water (물 속에서 레이저에 의하여 생성된 기포의 거동 및 복사현상)

  • Karng, Sarng-Woo;Byun, Ki-Taek;Kwak, Ho-Young
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1282-1287
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    • 2004
  • The bubble behavior and the radiation mechanism from a laser-induced collapsing bubble were investigated theoretically using the Keller-Miksis equation for the bubble wall motion and analytical solutions for the vapor inside bubble. The calculated time dependent bubble radius is in good agreement with observed ones. The half-width of the luminescence pulse at the collapse point, which was calculated under assumption that the light emission mechanism is black body radiation from the vapor bubble agreed well with observed value of several nanoseconds. The gas content inside the vapor bubble was too small to produce the light emission due to bremsstrahlung.

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