• Transactions on Electrical and Electronic Materials
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• v.15 no.6
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• pp.333-337
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• 2014

In this study, the use of a discharging process for charged particles is proposed to achieve an ideal electrical balance or neutralization and to improve the electrical and optical properties of a reflective electronic display. Here, negatively charged particles (white) and positively charged particles (black) are used. The q/m (charge per mass for a particle) values of the black and white particles are $+4.5{\mu}C/g$ and $-4.5{\mu}C/g$, respectively. We compared the movement of the charged particles by varying their discharging time. Stable movement of the charged particles is obtained with an appropriate discharging time, which resulted in improvements of the optical properties of the panel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.12
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• pp.1057-1062
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• 2008

The ${\alpha}-In_2S_3:Co^{2+}$ single crystal with a good quality and stabilized property were gained successfully by the CTR(Chemical Transport Reaction)method. XRD analysis showed that the grown single crystals were cubic structure. The optical absorption spectra of ${\alpha}-In_2S_3:Co^{2+}$ single crystal showed impurity absorption peaks due to cobalt impurity. These impurity absorption pesks were assigned to the ligand transition between the split energy levels of $Co^{2+}$ ions sited in $T_d$ symmetry of these semiconductor host lattice.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1586-1589
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• 2007

The influence of optical components constituting the backlight of TV on the luminance property of backlight was analyzed. The variation of luminance when the light emitted from light source passes each optical part was evaluated.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.3
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• pp.13-20
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• 2003

This study was carried out to investigate the effect of surface modified pigments on the properties of coated paper. The selected core particle(clay, talc) and fine particle(TiO$_2$) were modified by hybridization. The optical properties of modified pigments, rheological properties of coating color, and optical properties of coated paper were investigated. It was found that particles formed sphere-like shape and became more uniform during the surface modification in the hybridization system. As a result, It was estimated that surface modification of TiO$_2$ turned out to be more effective in improving optical properties of pigment and coated paper than simply blending it.

• Journal of Sensor Science and Technology
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• v.23 no.1
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• pp.1-6
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• 2014

In many medical image devices, dc noise often prevents normal diagnosis. In wireless capsule endoscopy systems, multipath fading through indoor wireless links induces inter-symbol interference (ISI) and indoor electric devices generate impulsive noise in the received signal. Moreover, dc noise, ISI, and impulsive noise are also found in optical fiber communication that can be used in remote medical diagnosis. In this paper, a blind signal processing method based on the biased probability density functions of constant modulus error that is robust to those problems that can cause error propagation in decision feedback (DF) methods is presented. Based on this property of robustness to error propagation, a DF version of the method is proposed. In the simulation for the impulse response of optical fiber channels having slowly varying dc noise and impulsive noise, the proposed DF method yields a performance enhancement of approximately 10 dB in mean squared error over its linear counterpart.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.555-557
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• 1995

In near field optics, optical fiber probe is smaller than the wavelength of light. This small probe makes it possible to overcome the diffraction limit due to wave property of light. In conventional optical systems, the image resolution is governed by wavelength. But in NSOM, it is determined by probe tip size and probe shape. Therefore probe tip size and shape are very important points in near field optics. In this paper, we will suggest the new fabrication methods of optical fiber probe and show that the probe tip size is sub-micrometer using SEM.

• Transactions of Materials Processing
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• v.12 no.4
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• pp.296-301
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• 2003

Though a glass tens has outstanding optical performance, it has not been widely used because manufacturing process shows poor productivity and high cost. However, press-forming method of glass lens overcomes these disadvantages with mass production. When glass lens is produced by press-forming method using closed die, it is needed that the volume of glass lens preform is precisely measured in order to prevent incomplete products and to increase in life of die. The present. paper shows the shortcoming of forming process with closed die, and performs FEM simulation of forming process with open die in order to overcome this shortcoming. The design parameters of open die are selected on the basis of assembly with optical module and maintenance of optical performance. FEM simulation is carried out with selected parameter of open die and two basic preform. According to distribution of effective strain in glass lens, optical property of glass lens formed at each set of die and preform is compared.

• Korean Journal of Optics and Photonics
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• v.11 no.1
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• pp.19-24
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• 2000

Optical transmission characteristics of retardation film for obliquely incident light is calculated by using extended Jones calculus and it is geometrically interpreted on Poincare sphere representation as rotational transformation. The characteristics of a retardation film is that while the rotation axis is fixed at a point on the Equator of the Poincar sphere, the rotation angle varies with the direction of incidence. This property can be compensated by using a tandem arrangement of the two optical films whose optic axes do not coincident, and this method can be used for the improvement of the viewing angle characteristics of BTN cells. cells.

• Journal of the Optical Society of Korea
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• v.14 no.3
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• pp.185-189
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• 2010

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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.828-830
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• 2000

Various substrates were compared for the investigation of the optical properties of ZnO thin films. ZnO thin films have been deposited on (100) p-type silicon substrates and (001) sapphire substrates by pulsed laser deposition technique using a Nd:YAG laser with the wavelength of 355 nm. Oxygen and nitrogen gases were used as ambient gases. Substrate temperatures were varied in the range of 200$^{\circ}C$ to 600$^{\circ}C$ at a fixed ambient gas pressure of 350 mTorr. ZnO films have been deposited on various substrates, such as Si and sapphire wafers. We have investigated substrate effect on the optical and structural properties of ZnO thin films using X-ray diffraction (XRD) and photoluminescence (PL).