• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.10a
• /
• pp.856-857
• /
• 2005

• Journal of the Optical Society of Korea
• /
• v.17 no.1
• /
• pp.110-110
• /
• 2013

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.207-208
• /
• 2007

• Korean Journal of Optics and Photonics
• /
• v.22 no.4
• /
• pp.161-169
• /
• 2011

In this paper, a tolerance allocation method using Monte-Carlo simulation with measured reflective eccentricity for high-sensitive IR optics is proposed. During optics fabrication and alignment, reflective eccentricity was measured using an optical centration measurement instrument. A Monte-Carlo simulation was performed using measured eccentricity data, and it gives statistical estimated performance of the optics after fabrication. The validity of the proposed tolerance allocation method was verified comparing the estimated MTF result with the measured MTF result of the fabricated optics.

• Current Optics and Photonics
• /
• v.7 no.4
• /
• pp.457-462
• /
• 2023

Quantitative measurement of trace ethane is important in environmental science and biomedical applications. For these applications, we typically require a few tens of part-per-trillion level measurement sensitivity. To measure trace-level ethane, we constructed a cavity ring-down spectroscopy setup in the 3.37 ㎛ mid-infrared wavelength range, which is applicable to multi-species chemical analysis. We demonstrated that the detection limit of ethane is approximately 300 parts per trillion, and the measured concentration is in agreement with the amounts of the injected sample. We expect that these results can be applied to the chemical analysis of ethane and applications such as breath test equipment.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.05a
• /
• pp.1072-1073
• /
• 2005

• Journal of the Optical Society of Korea
• /
• v.18 no.3
• /
• pp.244-250
• /
• 2014

Due to the difficulty in measuring very low out-of-band cutoff depths of solar blind UV filters, we propose a cutoff depth adjustable measurement system (CDAM) to test deep cutoff filters with a large dynamic range. The CDAM utilizing the substitution method is elaborately composed of several parts, including narrow-band LED light sources, standard reflective neutral attenuators with known attenuation coefficients, and a photomultiplier (PMT). This paper also presents an attenuator combination method ensuring that the PMT works within its linear response range. In addition, numerical simulation testifies to the method, and experiment shows that the CDAM system can achieve an extension of dynamic range from 0-6 OD to 0-10 OD, which is sufficient for the measurement of out-of-band cutoff depths of solar blind UV filters. Above all, the CDAM system, being easily implemented, of wide dynamic range, and highly precise, could be widely used in the measurement of filter cutoff depth.

• Journal of Korean Ophthalmic Optics Society
• /
• v.4 no.1
• /
• pp.57-61
• /
• 1999

This is a study of measurement of inter Reading Pupillary Distance (P.D.) in 729 old aged farmers (aged over 50). The average of Reading Pupillary Distance (P.D.) in man (58.93mm) is bigger than in woman (57.82mm), and the O.C. of Ready-made Reading Spectacles is 68.98mm.

• Journal of the Optical Society of Korea
• /
• v.12 no.4
• /
• pp.298-302
• /
• 2008

We have developed a 270-W 15-kHz MOPA system based on side-pumped rod-type Nd:YAG gain modules. The master oscillator is a 3-W 15-kHz $TEM_{00}$ $Nd:YVO_4$ laser with a pulse duration of 30 ns. To preserve the high beam quality during the amplification, we use image relay and polarization rotation which can simultaneously compensate for thermal lensing and thermal birefringence generated in the rod-type gain modules. After the amplification to 270 W with six rod-type gain modules, the beam quality factor ($M^2$) of the amplified laser beam is 5-10, and the pulse duration is maintained at 30 ns.

• Journal of Korean Ophthalmic Optics Society
• /
• v.9 no.1
• /
• pp.125-134
• /
• 2004

By applying the test methods of "Protection Eyewear Standard (KS P 8147)", "Glasses Frame Standard (KS G 3306)" and "Lens Standard for Sunglasses (KS P 4404)", this study analyzed optical functions of sunglasses now being sold in a road shop (A shop), a fashion goods store (B shop), a shop of highway rest area (C shop) and an optical shop (D shop). When compared with sunglasses (UV transmittance rate 8.8%) of a road shop, UV Block effects of sunglasses (UV transmittance rate 0.7%) of an optical shop showed good results. In addition, the average surface resistance against abrasion for sunglasses which was sold at an optical shop was 1.4% that was much higher than that of sunglasses of a road shop(2.2%).