Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Optical Society of Korea
Journal Basic Information
Journal DOI :
Optical Society of Korea
Editor in Chief :
Volume & Issues
Volume 14, Issue 4 - Dec 2010
Volume 14, Issue 3 - Sep 2010
Volume 14, Issue 2 - Jun 2010
Volume 14, Issue 1 - Mar 2010
Selecting the target year
The Measurement of the LIDAR Ratio by Using the Rotational Raman LIDAR
Choi, Sung-Chul ; Baik, Sung-Hoon ; Park, Seung-Kyu ; Cha, Hyung-Ki ; Song, Im-Kang ; Kim, Duk-Hyeon ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 174~177
DOI : 10.3807/JOSK.2010.14.3.174
The rotational Raman LIDAR technique has been used to accurately measure aerosol optical properties such as backscatter coefficient, extinction coefficient, and LIDAR ratio. In the case of the vibrational Raman technique, the
om exponent, which has wavelength dependence on the particle properties, is assumed to obtain the extinction coefficient. However, this assumed
m exponent can cause systematic errors in retrieving aerosol optical properties. In the case of the rotational Raman technique, the aerosol optical properties can be measured without any assumptions about the
m exponent. In this paper, the LIDAR ratio was measured by using the rotational Raman LIDAR and vibrational Raman LIDAR in the troposphere. And, the LIDAR ratios measured by these two methods were compared.
Depolarization Ratio Retrievals Using AERONET Sun Photometer Data
Lee, Kyung-Hwa ; Muller, Detlef ; Noh, Young-Min ; Shin, Sung-Kyun ; Shin, Dong-Ho ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 178~184
DOI : 10.3807/JOSK.2010.14.3.178
We present linear particle depolarization ratios (LPDRs) retrieved from measurements with an AERONET Sun photometer at the Gwangju Institute of Science and Technology (GIST), Korea (
) between 19 October and 3 November 2009. The Sun photometer data were classified into three categories according to
exponent and size distribution: 1) pure Asian dust (19 October 2009), 2) Asian dust mixed with urban pollution observed in the period from 20-26 October 2009, and 3) clean conditions (3 November). We show that the LPDRs can be used to distinguish among Asian dust, mixed aerosol, and non-Asian dust in the atmosphere. The mean LPDR of the pure Asian dust case is 23 %. Mean LPDRs are 13 % for the mixed case. The lowest mean LPDR is 6 % in the clean case. We compare our results to vertically resolved LPDRs (at 532 nm) measured by a Raman LIDAR system at the same site. In most cases, we find good agreement between LPDRs derived with Sun photometer and measured by LIDAR.
Aerosol Measurement and Property Analysis Based on Data Collected by a Micro-pulse LIDAR over Shanghai, China
Huang, Xingyou ; Yang, Xiaowu ; Geng, Fuhai ; Zhang, Hua ; He, Qianshan ; Bu, Lingbing ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 185~189
DOI : 10.3807/JOSK.2010.14.3.185
A micro-pulse LIDAR system (MPL) was employed to measure the aerosol over Pudong, Shanghai from July 2008 to January 2009. Based on Fernald method, aerosol optical variables such as extinction coefficient were retrieved and analyzed. Results show that aerosol exists mainly in low layers; aerosol loading reaches its maximum in the afternoon, and then decreases with time until its minimum at night. Most of the aerosol concentrates in the layer below 3 km, and optical extinction coefficient in the layer below 2 km contributes 84.25% of that below 6 km. Two extinction coefficient peaks appear in the near surface layer up to 500 m and in the level around 1000 m. Aerosol extinction coefficient shows a seasonal downward trend from summer to winter.
A Combined Atmospheric Radiative Transfer Model (CART): A Review and Applications
Chen, Xiuhong ; Wei, Heli ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 190~198
DOI : 10.3807/JOSK.2010.14.3.190
A set of radiative transfer software named CART (Combined Atmospheric Radiative Transfer) has been developed to rapidly calculate atmospheric transmittance and background radiance. The spectral resolution of CART is
, and the spectral region covers from 1 to
. CART has five characteristic features, and it can be applied to many fields. The features and applications of CART are summarized in detail.
Doppler LIDAR Measurement of Wind in the Stratosphere
Dong, Jihui ; Cha, Hyun-Ki ; Kim, Duk-Hyeon ; Baik, Sung-Hoon ; Wang, Guocheng ; Tang, Lei ; Shu, Zhifeng ; Xu, Wenjing ; Hu, Dongdong ; Sun, Dongsong ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 199~203
DOI : 10.3807/JOSK.2010.14.3.199
A mobile direct detection Doppler LIDAR based on molecular backscattering for measurement of wind in the stratosphere has been developed in Hefei, China. First, the principle of wind measurement with direct detection Doppler LIDAR is presented. Then the configuration of the LIDAR system is described. Finally, the primary experimental results are provided and analyzed. The results indicate that the detection range of the designed Doppler LIDAR reached 50 km altitude, and there is good consistency between the molecular Doppler wind LIDAR(DWL) and the wind profile radar(WPR) in the low troposphere.
2-dimensional Mapping of Sulfur Dioxide and Bromine Oxide at the Sakurajima Volcano with a Ground Based Scanning Imaging Spectrograph System
Lee, Han-Lim ; Kim, J.-Hoon ; Ryu, Jae-Yong ; Kwon, Soon-Chul ; Noh, Young-Min ; Gu, Myo-Jeong ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 204~208
DOI : 10.3807/JOSK.2010.14.3.204
A scanning imaging spectrograph system was used in this study to retrieve readings of the 2-D distribution of
and BrO around the crater of the Sakurajima volcano in Japan. The measurement was carried out during the daytime on November 2, 2005. Measurements were made at the surface of the site, located 5 km from the Sakurajima crater. One hundred horizontal scans were performed. Each column scanned by the system consists of 64 vertical pixels in order to retrieve the spatial distributions of BrO and
in the plume in terms of slant column densities (SCDs). Measured spectra were analyzed to identify and quantify
and BrO in the volcanic plume utilizing the plume's specific absorption features in the ultra violet region. Two-dimensional BrO and
distributions in SCD were retrieved horizontally covering the upwind, crater and downwind areas, and vertically, including the plume in the center of the scanned image. Both horizontal and vertical dispersions of
SCD from the crater were successfully measured to be from
. However, BrO was measured below
, which is considered its background level.
Selecting Characteristic Raman Wavelengths to Distinguish Liquid Water, Water Vapor, and Ice Water
Park, Sun-Ho ; Kim, Yong-Gi ; Kim, Duk-Hyeon ; Cheong, Hai-Du ; Choi, Won-Seok ; Lee, Ji-In ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 209~214
DOI : 10.3807/JOSK.2010.14.3.209
The Raman shift of water vapor is 3657
, and this Raman signal can be easily separated from other Raman signals or elastic signals. However, it is difficult to make simultaneous Raman measurements on the three phases of water, namely, ice water, liquid water, and water vapor. This is because we must consider the overlap between their Raman spectra. Therefore, very few groups have attempted to make Raman simultaneous measurements even on two elements (water vapor and liquid water, or water vapor and ice water). We have made an effort to find three characteristic Raman wavelengths that correspond to the three phases of water after measuring full Raman spectra of water on particular days that are rainy, snowy or clear. Finally, we have found that the 401-nm, 404-nm, and 408-nm wavelengths are the most characteristic Raman wavelengths that are representative of the water phases when we are using the 355-nm laser wavelength for making measurements.
Aerosol Observation with Raman LIDAR in Beijing, China
Xie, Chen-Bo ; Zhou, Jun ; Sugimoto, Nobuo ; Wang, Zi-Fa ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 215~220
DOI : 10.3807/JOSK.2010.14.3.215
Aerosol observation with Raman LIDAR in NIES (National Institute for Environmental Studies, Japan) LIDAR network was conducted from 17 April to 12 June 2008 over Beijing, China. The aerosol optical properties derived from Raman LIDAR were compared with the retrieved data from sun photometer and sky radiometer observations in the Aerosol Robotic Network (AERONET). The comparison provided the complete knowledge of aerosol optical and physical properties in Beijing, especially in pollution and Asian dust events. The averaged aerosol optical depth (AOD) at 675 nm was 0.81 and the Angstrom exponent between 440 nm and 675 nm was 0.99 during experiment. The LIDAR derived AOD at 532 nm in the planetary boundary layer (PBL) was 0.48, which implied that half of the total AOD was contributed by the aerosol in PBL. The corresponding averaged LIDAR ratio and total depolarization ratio (TDR) were 48.5sr and 8.1%. The negative correlation between LIDAR ratio and TDR indicated the LIDAR ratio decreased with aerosol size because of the high TDR associated with nonspherical and large aerosols. The typical volume size distribution of the aerosol clearly demonstrated that the coarse mode radius located near 3
in dust case, a bi-mode with fine particle centered at 0.2
and coarse particle at 2
was the characteristic size distribution in the pollution and clean cases. The different size distributions of aerosol resulted in its different optical properties. The retrieved LIDAR ratio and TDR were 41.1sr and 19.5% for a dust event, 53.8sr and 6.6% for a pollution event as well as 57.3sr and 7.2% for a clean event. In conjunction with the observed surface wind field near the LIDAR site, most of the pollution aerosols were produced locally or transported from the southeast of Beijing, whereas the dust aerosols associated with the clean air mass were transported by the northwesterly or southwesterly winds.
Measurement of Aerosol Parameters with Altitude by Using Two Wavelength Rotational Raman Signals
Song, Im-Kang ; Kim, Yong-Gi ; Baik, Sung-Hoon ; Park, Seung-Kyu ; Cha, Hyung-Ki ; Choi, Sung-Chul ; Chung, Chin-Man ; Kim, Duk-Hyeon ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 221~227
DOI : 10.3807/JOSK.2010.14.3.221
Aerosol size distribution provides good information for predicting weather changes and understanding cloud formation. Aerosol extinction coefficient and backscattering coefficient are measured by many scientists, but these parameters depend not only on aerosol size but on aerosol concentrations. An algorithm has been developed to measure aerosol parameters such as
m exponent, color ratio, and LIDAR ratio without any assumptions by using two wavelength rotational Raman LIDAR signals. These parameters are good indicators for the aerosol size. And we can find
m exponent, color ratio, and LIDAR ratio under various weather conditions. Finally, it can be seen that the
m exponent has an inverse relationship to the particle size of the aerosol and the color ratio is linearly dependent on the aerosol size. An
m exponent from 1.2 to 3.1, a color ratio from 0.28 to 1.04, and a LIDAR ratio 66.9 sr at 355 nm and 32.6 sr at 532 nm near the cloud were obtained.
Joint-characteristic Function of the First- and Second-order Polarization-mode-dispersion Vectors in Linearly Birefringent Optical Fibers
Lee, Jae-Seung ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 228~234
DOI : 10.3807/JOSK.2010.14.3.228
This paper presents the joint characteristic function of the first- and second-order polarization-modedispersion (PMD) vectors in installed optical fibers that are almost linearly birefringent. The joint characteristic function is a Fourier transform of the joint probability density function of these PMD vectors. We regard the random fiber birefringence components as white Gaussian processes and use a Fokker-Planck method. In the limit of a large transmission distance, our joint characteristic function agrees with the previous joint characteristic function obtained for highly birefringent fibers. However, their differences can be noticeable for practical transmission distances.
Development of Respiration Sensors Using Plastic Optical Fiber for Respiratory Monitoring Inside MRI System
Yoo, Wook-Jae ; Jang, Kyoung-Won ; Seo, Jeong-Ki ; Heo, Ji-Yeon ; Moon, Jin-Soo ; Park, Jang-Yeon ; Lee, Bong-Soo ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 235~239
DOI : 10.3807/JOSK.2010.14.3.235
In this study, we have fabricated two types of non-invasive fiber-optic respiration sensors that can measure respiratory signals during magnetic resonance (MR) image acquisition. One is a nasal-cavity attached sensor that can measure the temperature variation of air-flow using a thermochromic pigment. The other is an abdomen attached sensor that can measure the abdominal circumference change using a sensing part composed of polymethyl-methacrylate (PMMA) tubes, a mirror and a spring. We have measured modulated light guided to detectors in the MRI control room via optical fibers due to the respiratory movements of the patient in the MR room, and the respiratory signals of the fiber-optic respiration sensors are compared with those of the BIOPAC
system. We have verified that respiratory signals can be obtained without deteriorating the MR image. It is anticipated that the proposed fiber-optic respiration sensors would be highly suitable for respiratory monitoring during surgical procedures performed inside an MRI system.
Current-induced Phase Demodulation Using a PWM Sampling for a Fiber-optic CT
Park, Hyoung-Jun ; Lee, June-Ho ; Kim, Hyun-Jin ; Song, Min-Ho ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 240~244
DOI : 10.3807/JOSK.2010.14.3.240
In this work, we used PWM sampling for demodulation of a fiber-optic interferometric current transformer. The interference signal from a fiber-optic CT is sampled with PWM triggers that produce a 90-degree phase difference between two consecutively sampled signals. The current-induced phase is extracted by applying an arctangent demodulation and a phase unwrapping algorithm to the sampled signals. From experiments using the proposed demodulation, we obtained phase measurement accuracy and a linearity error, in AC current measurements, of ~2.35 mrad and 0.18%, respectively. The accuracy of the proposed method was compared with that of a lock-in amplifier demodulation, which showed only 0.36% difference. To compare the birefringence effects of different fiber-optic sensor coils, a flint glass fiber and a standard single-mode fiber were used under the same conditions. The flint glass fiber coil with a Faraday rotator mirror showed the best performance. Because of the simple hardware structure and signal processing, the proposed demodulation would be suitable for low-cost over-current monitoring in high voltage power systems.
Image-processing Based Panoramic Camera Employing Single Fisheye Lens
Kweon, Gyeong-Il ; Choi, Young-Ho ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 245~259
DOI : 10.3807/JOSK.2010.14.3.245
We have developed mathematically precise image-processing algorithms for extracting panoramic images from fisheye images. Furthermore, we have successfully built a DSP-based panoramic camera employing single fisheye lens.
Transflective Dual Operating Mode Liquid Crystal Display with Wideband Configuration
Lee, Joong-Ha ; Kim, Tae-Hyung ; Yoon, Tae-Hoon ; Kim, Jae-Chang ; Jhun, Chul-Gyu ; Kwon, Soon-Bum ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 260~265
DOI : 10.3807/JOSK.2010.14.3.260
This paper proposes a transflective configuration of the dual operating mode liquid crystal display, which has transmissive dynamic and reflective memory parts in its pixel. By employing a wideband structure and optimizing the cell-gap of the liquid crystal layer, the reflective memory part shows a very low reflectance in the dark state, good dispersion properties for the entire visible range, as well as high reflectance in the bright state. The transmissive dynamic part is designed to have the same cell-gap and rubbing direction as those of the reflective part. The driving voltage of the dynamic part and transmittance of the bright state can also be controlled by using compensation film with a positive a-plate, which can compensate the reflective part. Experimental results in the memory part operation demonstrate that the contrast ratio is over 50:1 and the reflectance in the dark state is reduced to 56% on average of that of the conventional dual mode configuration for the entire visible range. The contrast ratio of the dynamic part is 300:1.
Optical System with 4 ㎛ Resolution for Maskless Lithography Using Digital Micromirror Device
Lee, Dong-Hee ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 266~276
DOI : 10.3807/JOSK.2010.14.3.266
In the present study, an optical system is proposed for maskless lithography using a digital micromirror device (DMD). The system consists of an illumination optical system, a DMD, and a projection lens system. The illumination optical system, developed for 95% uniformity, is composed of fly's eye lens plates, a 405 nm narrow band pass filter (NBPF), condensing lenses, a field lens and a 250W halogen lamp. The projection lens system, composed of 8 optical elements, is developed for 4
resolution. The proposed system plays a role of an optical engine for PCB and/or FPD maskless lithography. Furthermore, many problems arising from the presence of masks in a conventional lithography system, such as expense and time in fabricating the masks, contamination by masks, disposal of masks, and the alignment of masks, may be solved by the proposed system. The proposed system is verified by lithography experiments which produce a line pattern with the resolution of 4
Optimal Design of Dielectric-loaded Surface Plasmon Polariton Waveguide with Genetic Algorithm
Jung, Jae-Hoon ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 277~281
DOI : 10.3807/JOSK.2010.14.3.277
We propose a design and optimization method for a dielectric-loaded surface plasmon polariton waveguide using a genetic algorithm. This structure consists of a polymer ridge on top of two layers of substrate and gold film. The thickness, width and refractive index of the ridge are designed to optimize the figures of merit including mode confinement and propagation length. The modal analysis combined with the effective index method shows that the designed waveguide exhibits a fundamental propagation mode with high mode confinement while ensuring that the propagation loss remains relatively low.
Terahertz Wave Transmission Properties of Metallic Periodic Structures Printed on a Photo-paper
Lee, Sung-Ho ; Gee, Sang-Yoon ; Kang, Chul ; Kee, Chul-Sik ;
Journal of the Optical Society of Korea, volume 14, issue 3, 2010, Pages 282~285
DOI : 10.3807/JOSK.2010.14.3.282
We printed a one-dimensional array of metallic wires and a two-dimensional array of metallic split ring resonators on a photo-paper by using a high-dots-per-inch resolution printer and an ink with silver nano-particles. The printed sample sizes are
. The transmission measured by a terahertz time domain spectroscopy system shows that the arrays of wires and split ring resonators could act as polarizers and band-stop filters, respectively, in a terahertz frequency region.