Abstract: The present invention provides a cell or stack for evaluating the performance of a fuel cell and a method of evaluating the performance of the fuel cell using the cell or stack, in which a semiconductor thermoelectric device, attached to the side surface of the unit cell or stack of the fuel cell, is provided maintain the cell or stack at a uniform temperature. The temperatures of an anode and a cathode of the fuel cell can be precisely changed or maintained such that the performance of the fuel cell can also be measured in sub-zero temperature conditions without requiring a separate environmental chamber. A rate of temperature decrease, at which the temperature decreases to a certain sub-zero temperature, or a rate of temperature increase can be precisely controlled.

Abstract: Disclosed are a micro-fluidic structure for detecting biomolecules and a micro-fluidic device having the same. More particularly, a target material including at least two cis-diols is detected by a first material containing a boronate moiety and a second material containing another boronate moiety while generating electrical signals.

Abstract: Provided is a method for fabricating membrane electrode assembly (MEA) on a polymer electrolyte membrane fuel cell. The method includes adhering or fixing the first backing film to a polymer electrolyte membrane; forming a first catalyst layer on the polymer electrolyte membrane; removing the first backing film; adhering or fixing the second backing film to the first catalyst layer formed on the surface of the polymer electrolyte membrane; forming the second catalyst layer on the other side of the polymer electrolyte membrane; and removing the second backing film to complete the MEA.

Abstract: Provided is an apparatus for detecting leak in fuel cells. The apparatus includes: a detection gas intake unit connected to a detection gas storage; a supply unit supplying detection gas to supply manifolds of the fuel cells; a recovering unit connected to exhaust manifolds of the fuel cells; and a measuring unit measuring pressure of the detection gas supplied to the fuel cells, wherein in the fuel cells, a product and cooling fluid are exhausted through the exhaust manifolds after cathode/anode reaction gas and cooling fluid are supplied to the inside through the supply manifolds to generate an electrochemical reaction. Accordingly, presence of leak and leaked portions of the entire fuel cells are detected by using an inert detection gas.

Abstract: Disclosed is an integrated multi-measurement system for measuring physical properties including thickness, electrical resistance and differential pressure of a gas diffusion layer for a polymer electrolyte fuel cell with respect to compression. The integrated multi-measurement system simultaneously measures changes in the physical properties of the gas diffusion layer depending on pressure upon measurement of the physical properties of the gas diffusion layer of the fuel cell and also measures through-plane permeability in which a gas is passed through a sample in a direction perpendicular to the sample and in-plane permeability in which a gas is passed through a sample in a direction parallel to the sample.

Abstract: A highly proton conductive polymer electrolyte composite membrane for a fuel cell is provided. The composite membrane includes crosslinked polyvinylsulfonic acid. The composite membrane is produced by impregnating a mixed solution of vinylsulfonic acid as a monomer, a hydroxyl group-containing bisacrylamide as a crosslinking agent and a photoinitiator or thermal initiator into a microporous polymer support, polymerizing the monomer, and simultaneously thermal-crosslinking or photo-crosslinking the polymer to form a chemically crosslinked polymer electrolyte membrane which is also physically crosslinked with the porous support. Further provided is a method for producing the composite membrane in a simple manner at low cost as well as a fuel cell using the composite membrane.

Abstract: Provided are a fuel cell with a porous gas diffusion layer having a flow channel and a method for manufacturing the same. A metal separator without a flow channel is used, but a flow channel for providing a reaction gas is formed in a gas diffusion layer made of a porous material. This improves precision of stack manufacturing and allows free design of the cooling part. The gas diffusion layer is made of a porous metal material so as to maximize electrical transfer efficiency and improve endurance against physical stress.

Abstract: An optical system is provided. The optical system includes a luminous system which comprises a plurality of light source devices and an image unit; and a projection system which receives light having an image through the luminous system, and enlarges and projects the light, wherein the plurality of light source devices comprise a reflection member which reflects light beam emitted from the light source devices, and are disposed so that the light beam emitted from the light source devices is reflected by the reflection member one time and enters to the image unit.

Abstract: An illumination optical unit and a display apparatus having the same are provided. The display apparatus includes an illumination optical unit which generates and illuminates light; a display element which forms an image by the light illuminated from the illumination optical unit; and a projection optical unit which projects the image formed in the display element on a screen. The illumination optical unit includes a light source which includes a light emitting area, and a polarization converting unit which includes a plurality of polarization prisms which polarize and convert an entering light from the light source. The light source is disposed so that a long width of the light emitting area corresponds to a long width of the polarization prisms.

Abstract: An illumination unit and an image projection apparatus employing the same. The illumination unit includes: a first reflective surface reflecting light incident thereon; a light-emitting device generating and emitting illuminating light; and a second reflective surface reflecting light emitted from the light-emitting device to a light source surface that includes the light-emitting device.

Abstract: A light emitting diode (LED) module includes a plurality of LEDs which emit light, and a metal substrate on which the LEDs are mounted and which includes a fixing part to be directly fixed to an outer frame, wherein the metal substrate is a heat sink that absorbs heat generated by the LEDs.

Abstract: An illumination unit includes multiple light source units to emit light having different wavelengths, and a synthesizing prism to synthesize the emitted light. The synthesizing prism includes a first triangular prism (tp) having a first outer surface (os) to transmit (reflect) the light according to the light's input a direction, and first and second boundary surfaces (bs), a second tp having a second os to transmit the light, a third bs facing the second bs, and a fourth bs, a third tp having a third os to transmit (reflect) the light according the light's input direction, a fifth bs facing the fourth bs, and a sixth bs facing the first bs, and a color separation portion arranged at least one of positions between the second and third bs, the fourth and fifth bs, and the sixth and first bs, to selectively transmit (reflect) the light according to wavelengths thereof.

Abstract: An illumination unit includes first, second, third, and fourth light source units to emit first, second, third, and fourth light beams of different wavelength bands, and a hexahedral color synthesis prism to synthesize the first, second, third, and fourth light beams emitted from the first, second, third, and fourth light source units to propagate the first, second, third, and fourth light beams can propagate along the same path with respect to each other.

Abstract: The present invention provides a cell or stack for evaluating the performance of a fuel cell and a method of evaluating the performance of the fuel cell using the cell or stack, in which a semiconductor thermoelectric device, attached to the side surface of the unit cell or stack of the fuel cell, is provided so as to evaluate the performance of the fuel cell in an environment in which temperature is maintained at a uniform temperature. According to the present invention, the temperatures of an anode and a cathode of the fuel cell can be precisely changed or maintained. Further, the performance of the fuel cell can also be measured in sub-zero temperature conditions without requiring a separate environmental chamber. A rate of temperature decrease, at which the temperature decreases to a certain sub-zero temperature, or a rate of temperature increase can be precisely controlled.

Abstract: An illuminating unit having a plurality of light emitting devices and collimators and a projection type image display apparatus using the same are provided. The illuminating unit includes: a plurality of light emitting devices which output light beams of predetermined wavelengths; a plurality of collimators, each having a parabolic reflection surface for reflecting the light beam in a predetermined direction, a mounting section for locating the light emitting device at the focal point of the parabolic reflection surface, a light output surface opposite to the parabolic reflection surface, and a light guide section for guiding the light beam reflected from the parabolic reflection surface to the light output surface; and one or more fixing members having two or more steps for mounting the light emitting devices and the collimators on their top surface. A plurality of light emitting devices and collimators are efficiently arranged in a small space.

Abstract: An illumination unit with an improved color synthesis prism, which can synthesize light beams emitted from compact light sources, and a projection type image display apparatus employing the illumination unit.

Abstract: An illuminator includes a concave mirror to reflect incident light in a predetermined direction, an inner reflective mirror provided on an optical axis of the concave mirror and having a reflective surface at least one surface thereof, a light source installed on at least one surface of the inner reflective mirror to generate and illuminate light, and a retro-reflective mirror provided at a focal point of the light reflected from the concave mirror, or in a vicinity of the focal point, and having an aperture through which some of the light illuminated from the light source and reflected by the concave mirror passes and a retro-reflective surface to reflect remaining light not passing through the aperture back toward the concave mirror.

Abstract: A projection display including first through third light source units to radiate first through third light beams having different colors, respectively, a light path combining unit to combine paths of the first through third light beams, an optical modulator to sequentially modulate the first through third light beams according to image information, and a projection lens unit to magnify and project the modulated light beams onto a screen. The light path combining unit includes first and second prisms. The first prism includes first and second incidence surfaces, through which the first and second light beams are incident, respectively, a first emission surface, and a first selective reflection surface to transmit the second light beam toward the first emission surface.

Abstract: A projection display includes first through third light source units to radiate first through third light beams, respectively, having different colors, an X-cube prism to combine paths of the first through third light beams, an optical modulator to sequentially modulate the first through third light beams according to image information, and a projection lens unit to magnify and project the modulated light beams onto a screen. Each of the first through third light source units includes at least one optical module. The optical module includes a collimator having a first reflective surface in a parabolic shape, and a compact light source located in the vicinity of a focal point of the first reflective surface.

Abstract: A display device having a uniform brightness and control method thereof are provided, which includes a circuit board having a light emitting diode mounting area, a light source unit comprising a plurality of light emitting diodes mounted to the light emitting diode mounting area so that light emitting characteristics can be symmetrical around the center of the light emitting diode mounting area, a light uniformizing unit for creating a uniform light from the light emitting diodes, a micro display unit located in front of the light uniformizing unit, a projection lens unit located in front of the micro display unit, and a screen located in front of the projection lens unit. Thus, the display device provides uniform brightness and color.