Abstract: An optical printed circuit board system having a tapered optical waveguide is provided. The optical printed circuit board system includes a substrate as a printed circuit board having an electrical circuit and on which an electrical circuit chip is mounted, a system board including an optical bench coupled to the substrate and on which a photoelectrical signal chip electrically connected to the electrical circuit chip through the electrical circuit, an optical device electrically connected to the photoelectrical signal chip, and a first optical waveguide aligned to the optical device for optical coupling and tapered to have a smaller aperture in an output node for outputting the optical signals smaller than that in an input node for inputting the optical signals are mounted, and a back plane including a groove into which the system board is inserted and a second optical waveguide optically coupled to the first optical waveguide and tapered to have a smaller aperture in the output node than in the input node.

Abstract: A method of manufacturing an optical waveguide using a laser direct writing method is disclosed. More particularly, a method for improving refractive index profile of the optical waveguide by overlapping two or more beams using Gaussian laser beam is provided. In addition, it can accomplish an improved waveguide characteristics such as an offset structure of an S-bend type optical waveguide and an asymmetrical curve optical waveguide by individually adjusting the overlapped laser beams.

Abstract: Provided is a differential pair interconnection apparatus for providing a differential signal on a printed circuit board having signal paths for high-speed differential signals to an external circuit and providing a signal inputted from the external circuit to the printed circuit board without any signal distortion. According to the differential pair interconnection apparatus of the present invention, there can be provided two separate physical channels without impedance mismatching.

Abstract: An electro-optical circuit board (EOCB) in which an optical waveguide for transmitting an optical signal, and a driving unit/receiving unit and an optical source/optical detector for converting an electrical signal into the optical signal, and vice versa are integrated. The EOCB has a structure from which a lens is excluded for the purpose of an economical and efficient optical coupling between the optical waveguide and the optical source/optical detector. The optical source/optical detector are buried within a trench of a metal optical bench. The optical waveguide is then attached on the surface of the optical source/optical detector by means of an epoxy.

Abstract: An acetal group containing norbornene-based copolymer useful for a photoresist composition, a method for producing the same, and a photoresist composition containing the same are disclosed. According to the present invention, a copolymer of the present invention has excellent transparency at a wavelength of not more than about 250 nm, excellent resolution, excellent sensitivity, dry etching resistance and excellent adhesion to the substrate.

Abstract: A method of manufacturing an optical waveguide using a laser direct writing method is disclosed. More particularly, a method for improving refractive index profile of the optical waveguide by overlapping two or more beams using Gaussian laser beam is provided. In addition, it can accomplish an improved waveguide characteristics such as an offset structure of an S-bend type optical waveguide and an asymmetrical curve optical waveguide by individually adjusting the overlapped laser beams.

Abstract: The present invention discloses A method for producing a dot-printless light guide plate for a liquid crystal display device using an addition polymerized norbornene copolymer represented by the following general formula (1): wherein R1, R2, R3 and R4 are respectively a hydrogen atom, a C1˜C10 linear, branched or cyclic alkyl group, or —COOR7 in which R7 is a C1˜C10 linear, branched or cyclic alkyl group; R5 and R6 are respectively a hydrogen atom or a C1˜C10 linear, branched or cyclic alkyl group; and x is an integer of 0 to 4.

Abstract: The present invention relates to an electro-optical circuit board (EOCB) in which an optical waveguide for transmitting an optical signal, and a driving unit/receiving unit and an optical source/optical detector for converting an electrical signal into the optical signal, and vice versa are integrated. The EOCB has a structure from which a lens is excluded for the purpose of an economical and efficient optical coupling between the optical waveguide and the optical source/optical detector. The optical source/optical detector are buried within a trench of a metal optical bench. The optical waveguide is then attached on the surface of the optical source/optical detector by means of an epoxy. It is thus possible to minimize an alignment error between the optical source/optical detector and the optical waveguide.

Abstract: The present invention provides a composition for preparing substances having nano-pores, said composition comprising cyclodextrin derivative, thermo-stable organic or inorganic matrix precursor, and solvent for dissolving said two solid components. There is also provided an interlayer insulating film having evenly distributed nano-pores with a diameter less than 50 Å, which is required for semiconductor devices.

Abstract: The present invention provides a composition for preparing substances having nano-pores, said composition comprising cyclodextrin derivative, thermo-stable organic or inorganic matrix precursor, and solvent for dissolving said two solid components. There is also provided an interlayer insulating film having evenly distributed nano-pores with a diameter less than 50 Å, which is required for semiconductor devices.

Abstract: An acetal group containing norbornene-based copolymer useful for a photoresist composition, a method for producing the same, and a photoresist composition containing the same are disclosed. According to the present invention, a copolymer of the present invention has excellent transparency at a wavelength of not more than about 250 nm, excellent resolution, excellent sensitivity, dry etching resistance and excellent adhesion to the substrate.

Abstract: A styrene random copolymer includes at least one unit of styrene derivative and at least one unit of macromonomer. The at least one unit of styrene derivative is polymerized from a styrene derivative monomer of formula (1). The at least one unit of macromonomer is polymerized from a macromonomer of formula (2). In formulae (1) and (2), R1 is selected from the group consisting of hydrogen, halogen, and alkyl groups with 1˜20 carbon atoms, R2 is at least one selected from the group consisting of saturated hydrocarbons with 1˜20 carbon atoms, aromatic groups, and cycloalkyl groups with the proviso that R2 is not —CO— or —CH2—C6H4—, R3 is a saturated hydrocarbon group with 1˜10 carbon atoms, X is at least one ion polymerizable monomer unit. The amount of the macromonomer is 0.

Abstract: The present invention discloses A method for producing a dot-printless light guide plate for a liquid crystal display device using an addition polymerized norbornene copolymer represented by the following general formula (1): 1

Abstract: The metallocene complexes according to the present invention are prepared by reacting a transition metal complex of Group III-X of the Periodic Table, having at least one cycloalkanedienyl group, with a compound having at least two functional groups. The transition metal complex has a main ligand such as a cycloalkanedienyl group and at least one ancillary ligand which coordinated to a transition metal of Group III-X. The functional groups in the compound having at least two functional group are selected from the group consisting of a hydroxyl group (—OH), a thiol group (—SH), a primary amine group (—NH2), a secondary amine group (RNH—), a tertiary amine group (RR′N) a primary phosphorous group (—PH2), a secondary phosphorous group (RPH—), a tertiary phosphorous group (RR′P), a thiirane group etc.

Abstract: The new metallocene catalysts according to the present invention are prepared by reacting a metallocene compound with a compound having at least two functional groups. The metallocene compound is a transition metal compound, which is coordinated with a main ligand such as cyclopentadienyl group, and an ancillary ligand. The functional groups in the compound are selected from the group consisting of a hydroxyl group, an alkyl or aryl magnesium halide, a thiol group, a primary amine group, a secondary amine group, a primary phosphorous group, a secondary phosphorous group, etc. The metallocene catalysts according to the present invention have a structure in which an ancillary ligand of a metallocene compound is bonded to the functional groups of a compound having at least two functional groups. A structure of the metallocene catalysts can be varied with the type of a metallocene compound and a compound having at least two functional groups, and the molar ratio of each reactant.