Lg Chem, Ltd

Korea Advanced Institute of Science and Technology

Sk Innovation Co., Ltd.

Sk Geo Centric Co., Ltd.

Jun Haeng Lee

Yeon Keun Lee

Yun Chur Chung

Jung Doo Kim

Deok Hwan Kim

Chun Ju Youn

Do Young Kim

Han Min Seo

Nam Seok Bae

Cheol Ock Song

Keun Joo Park

Eui Seung Son

Sung Won Lee

Ki Yup Kim

Ji Hae Park

Joo Hyun Nam

Hyun Sik Yang

Chul Soon Moon

Yu Hyun Kim

Ho Seung Lee

Jang Won Chae

Provided are a biodegradable aliphatic-aromatic polyester copolymer having excellent hydrolysis resistance and high viscosity which has a carboxyl end group (CEG) content of 15 mg KOH/g or less, a ratio (Mz/Mn) of a z-average molecular weight (Mz) to a number average molecular weight (Mn) of 3 to 15, and a melt index (MI) of 5 g/10 min or less as measured under conditions of a temperature of 190° C. and a load of 2.16 kg in accordance with ASTM D 1238. A method of preparing a biodegradable aliphatic-aromatic polyester copolymer is provided, including adding a chain extender and an anti-hydrolysis agent to an aliphatic-aromatic polyester pre-copolymer over time, whereby a significant viscosity rise and improvement of hydrolysis resistance may be implemented simultaneously.

High-viscosity biodegradable aliphatic-aromatic polyester copolymer having excellent hydrolysis resistance and method of preparing the same

The present application relates to a method for producing a substrate which includes a step of exposing and developing a photosensitive resin composition layer formed on a surface of a substrate base layer to produce spacers. The method for producing a substrate of the present application can uniformly form spacers having a height according to a desired cell gap and can also freely control the height of the spacers.

Method for producing substrate

A liquid crystal cell, a manufacturing method thereof and a use thereof are provided in the present disclosure. The liquid crystal cell is in a normally transparent mode, and has excellent transmittance-variable characteristics in a transparent mode and a scattering mode and excellent haze characteristics in the scattering mode. Such liquid crystal cell may be applied to various light modulation devices, such as a smart window, a window protective film, a flexible display element, a light shielding plate for transparent displays, an active retarder for 3D image displays or a viewing angle control film.

Liquid crystal cell

A liquid crystal cell and a manufacturing method thereof and a use thereof are provided in the present disclosure. The liquid crystal cell is in a normally transparent mode, and has excellent transmittance-variable characteristics in a transparent mode and a scattering mode and excellent haze characteristics in the scattering mode. Such liquid crystal cell may be applied to various light modulation devices, such as a smart window, a window protective film, a flexible display element, a light shielding plate for transparent displays, an active retarder for 3D image displays or a viewing angle control film.

An optical fiber, and an optical access network, a local area network and optical parts for communication, which uses the optical fiber, are disclosed. The optical fiber whose core diameter is 10 &#x3bc;m&#x2dc;40 &#x3bc;m has at least two propagation modes in a wavelength over 1200 nm. The optical fiber according to the present invention can reduce packaging costs for optical components, since cross-sectional area of the core is large, compared with the prior art technique adopting a single mode optical fiber, and can transmit ultra-high speed data a relatively long distance, since the mode number and modal dispersion effect of the optical fiber is relatively small, compared with the prior art multimode optical fiber. Also, when using the optical fiber according to the present invention, the optical subscriber network and the local area network can be cost-effectively implemented. In addition, when adopting the optical fiber according to the present invention, productivity of optical components for communication can be improved, costs for an optical component can be reduced and quality of the optical component can be improved.

Optical fiber, and optical access network, local area network and optical parts for communication, which use the optical fiber

Disclosed is an apparatus for monitoring an optical signal-to-noise ratio in a WDM optical network. The apparatus includes an orthogonal polarization component module for receiving an optical signal and outputting it after removing a signal component thereof at a specific frequency band; and calculation means for measuring both average signal and noise component intensity of the optical signal outputted from the orthogonal polarization component module. By removing a signal component at a specific frequency bandwidth and passing only a noise component through, it is possible to easily measure the noise intensity within a signal bandwidth that cannot be measured in general. A frequency band is set within a signal bandwidth, and the signal intensity is minimized at the set frequency band, so that it is possible to measure the optical signal-to-noise ratio even for a signal whose amplified spontaneous emission noise spectrum is not flat, irrespective of the signal pattern length.

Apparatus for monitoring optical signal-to-noise ratio

A method and apparatus for minimizing system deterioration caused by polarization effects (e.g., a polarization-dependent gain (PDG), a polarization-dependent loss (PDL), and a polarization mode dispersion (PMD)). The apparatus performs a signal modulation process to enable one bit to simultaneously contain two orthogonal polarization components, resulting in a minimum DOP (Degree Of Polarization). If a signal undergoes the PMD, the apparatus converts an NRZ (Non Return to Zero) signal into an RZ (Return to Zero) signal, resulting in minimum inter-symbol interference caused by the PMD. The apparatus can improve a performance of an optical signal during the PMD operation, whereas a conventional PMD compensation technique has been designed to remove system deterioration caused by only the PMD.

Method and apparatus for reducing system deterioration caused by polarization effects

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Daejeon, South Korea

Jun Haeng Lee