• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.13 no.1
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• pp.15-20
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• 1999

A spectrophotorreter using two-beam type integrating sphere is developed, and the measurerrent accuracy is analyzed. The efficiency of the integrating sphere is analyzed, and the relation between the efficiency and the total measurerrent error is found. Especially, the integrating sphere is fabricated on the basis of its characteristics according to its shape such as the sample port. The perfonnance of the developed spectrophotorreter is tested using a black and a white standard reflectance plate, and the measurerrent error of $\pm0.5%$ is obtained.tained.

• Korean Journal of Optics and Photonics
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• v.34 no.5
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• pp.202-209
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• 2023

A KRISS-type small integrating sphere with a high spatial radiance uniformity was made using pressed polytetrafluoroethylene (PTFE) and a reflective rod to calibrate the spectral radiance responsivity of absolute radiant thermometers. The spatial radiance uniformity of the KRISS-type small integrating sphere was ±0.009%, five times higher than the best value reported by foreign national metrology institutions thus far. In addition, we improved the spatial radiance uniformity of a commercial sintered PTFE integrating sphere by a factor of 10.

• Journal of the Optical Society of Korea
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• v.20 no.4
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• pp.500-509
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• 2016

Integrating spheres play a central role in the radiometric calibration of remote sensors. With the development of the wide field of view (FOV) remote sensors, aperture diameters of remote sensors are becoming larger and larger. To satisfy the radiometric calibration requirements of full FOV and full aperture, an 8000mm diameter large aperture integrating sphere uniform source with a variable exit port was designed and manufactured. This integrating sphere will be used for pre-launch test and radiometric calibration of remote satellites. In this paper, optical theories were used to design the output spectral radiance. The LightTools software based on ray-tracing simulation method was used to determine the best combination and distribution of inner light sources. A spectral experiment was made to verify the spectral radiance design. To reduce the influence of longtime power-on, a new characteristic measurement method was developed to obtain the radiation characteristic of the integrating sphere, which could greatly improve the measuring efficiency. This method could also be applied to measure other large aperture uniform sources. The obtained results indicate that the spatial uniformity is 98.35%, and the angular uniformity at center position is 98.78%.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1355-1357
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• 2008

Reflection measurements are critical to the evaluation of display performance under ambient illumination conditions. Various hemispherical reflection methods are evaluated for their suitability and robustness across display technologies. The standard integrating sphere method is compared to a sampling sphere apparatus.

• Journal of Korean Ophthalmic Optics Society
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• v.2 no.1
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• pp.91-95
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• 1997

A General equation is developed for the efficiency of an integrating sphere with a nonuniform coating. The only assumptions are that the interior is a perfect sphere and that all areas reflect perfectly diffusely. The general equation are examined for the basic applications of integrating spheres as mixing mechanisms in hemispherical reflectance measurements and in absolute reflectance techniques.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.47-48
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• 2006

A roughness measuring system which comprises an integrating sphere and a stabilized laser has been fabricated with the aim of measuring the roughness correction value which is necessary in gauge block measurement by optical interferometry. To calibrate the system, a Newton's ring interferometer has been introduced. The method how to calibrate the roughness measurement system has been described.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.149-151
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• 2009

This paper gives a comparative analysis on the luminous efficiency of the bulb type LED lamps. we compare and analyze the measurement values bulb type LED lamps using both photogoniometer and integrating sphere. The volt and watt of one 1map are 220 V and 7 W, respectively. The volt and watt of other one are 100 V and 5.3 W, respectively. the values of those were 79.7 1m/W and 76.9 1m/W in the integrating sphere, respectively. Similarly, the values of those were 80.2 1m/W and 79.3 1m/W on the photogoniometer, respectively. As a result, the value of luminous efficiency can be measured using either integrating sphere or absolute goniometer regardless of the difference in case of bulb type LED lamps.

• Korean Journal of Optics and Photonics
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• v.22 no.2
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• pp.83-89
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• 2011

In order to improve the calculation speed of an integrating-sphere simulator based on a ray-tracing method, parallel processing with OpenMP directive was implemented into the simulator and the randomness of Monte Carlo method was guaranteed by utilizing a parallel random number generator. It was confirmed that simulation results obtained with more than $10^7$ rays showed good agreement with theoretical results within the error range of 0.5%, and that the calculation speed improved as the number of threads increased. Finally, the spatial response distribution functions of a real integrating sphere were simulated and compared with previous results.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.13-15
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• 2006

This paper describes the problem generated in PLS luminous flux measurement with integrating sphere. In RS case, we don't use the center position of the sphere but side position for flux test The difference of the lamp position makes the luminous flux difference of same light source. We confirmed the phenomenon with three other kinds of lamps and ensured the repeatability and reliability of this work at two laboratories. finally, the correction factor which should be applied for the PLS test at Side position was calculated.

• 전기산업
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• v.10 no.5
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• pp.32-46
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• 1999