Abstract: A constant velocity joint includes: an outer race provided with a through-hole extending along a longitudinal axis and forming a plurality of outer ball grooves; an inner race forming a plurality of inner ball grooves that respectively pair with the outer ball grooves; a plurality of balls that are respectively positioned within a space formed by the pair of the outer ball grooves and the internal ball grooves; a ball cage that accommodates the plurality of balls; and a grease retainer coupled to the outer race to prevent grease, which fills a space where the ball and the ball cage are placed, from leaking through the through-hole. The grease retainer has a convex shape protruding towards the ball and the ball cage.

Abstract: A grease sealing structure provides sealing grease filled between an outer race and an inner race of a constant velocity joint and includes: a boot formed to be closely fitted and supported on both the outer race and the inner race; a clamping cap configured to be fastened to the outer race so that a movement in an axial direction of the outer race is limited and to press the boot in the axial direction of the outer race to ensure the boot to be tightly fitted to the outer race; and a sealing ring configured to be fastened to the boot to press the boot against an outer circumferential surface of the inner race.

Abstract: An assembling device is a device for assembling a boot and a sealing ring to an inner race of a constant velocity joint in which a fixing part of the boot is fastened to the inner race by the sealing ring and includes: a guider provided with a guide surface on an outer surface to guide the boot and the sealing ring along a longitudinal direction of the inner race; and a pusher that provides a force to move the boot and the sealing ring along the guide surface to reach a support surface of the inner race.

Abstract: A method of manufacturing a semiconductor light emitting device, the method including forming a first conductivity-type semiconductor layer on a substrate; forming an active layer on the first conductivity-type semiconductor layer; forming a mask layer having an opening on the active layer; growing a second conductivity-type semiconductor layer through the opening; removing the mask layer; removing a portion of the active layer and a portion of the first conductivity-type semiconductor layer that do not overlap the second conductivity-type semiconductor layer; and removing a portion of the first conductivity-type semiconductor layer to expose the substrate.

Abstract: A method of manufacturing a semiconductor light emitting device, the method including forming a first conductivity-type semiconductor layer on a substrate; forming an active layer on the first conductivity-type semiconductor layer; forming a mask layer having an opening on the active layer; growing a second conductivity-type semiconductor layer through the opening; removing the mask layer; removing a portion of the active layer and a portion of the first conductivity-type semiconductor layer that do not overlap the second conductivity-type semiconductor layer; and removing a portion of the first conductivity-type semiconductor layer to expose the substrate.

Abstract: A tripod constant-velocity joint includes: an outer joint member having a cavity elongated in a longitudinal direction and three roller tracks; an inner joint member having a center body and three journals outwardly radially protruded from the center body; and three roller assemblies respectively coupled to the journal in a state of being respectively disposed in the roller tracks. The respective roller assembly comprises: an inner race which is connected to the journal and is provided with a first inner ball groove and a second inner ball groove on both lateral sides thereof; a first ball array and a second ball array respectively having a plurality of balls which are respectively disposed in the first inner ball groove and in the second inner ball groove; and a ball cage which restricts movements of the first ball array and the second ball array in a longitudinal direction thereof.

Abstract: A light emitting diode display device is provided.

Abstract: An ultraviolet semiconductor light emitting device includes a semiconductor stack, a trench, a filling insulator, and first and second electrodes. The semiconductor stack includes first and second conductivity-type semiconductor layers and an active layer therebetween that includes an AlGaN semiconductor material. The trench extends through the second conductivity-type semiconductor layer and the active layer to the first conductivity-type semiconductor layer and has a first width. The filling insulator fills the trench such that the filling insulator extends at least through the active layer in the trench and includes of an insulating material having a particular refractive index. The first electrode is connected to the first conductivity-type semiconductor layer, and the second electrode is connected to the second conductivity-type semiconductor layer.

Abstract: A semiconductor light emitting device includes a first conductivity-type semiconductor layer; an active layer covering a portion of the first conductivity-type semiconductor layer; and a second conductivity-type semiconductor layer covering a portion of the active layer, and sidewalls of the second conductivity-type semiconductor layer are spaced apart from sidewalls of the active layer along a horizontal direction.

Abstract: A semiconductor light emitting device includes a light emitting stack including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, a plurality of holes through the second conductive semiconductor layer and the active layer, a trench extending along an edge of the light emitting stack, the trench extending through the second conductive semiconductor layer and the active layer, and a reflective metal layer within the plurality of holes and within the trench.

Abstract: A light emitting device package includes a package substrate and a submount on the package substrate. An upper surface of the submount includes a central region, first and second base regions spaced from the package substrate, relative to the central region, and a sloped region between the central region and the first and second base regions. A light emitting device chip is in the central region. A first electrode layer is between the central region and the light emitting device chip and extends onto the sloped region and the first base region. A second electrode layer is between the central region and the light emitting device chip, extends onto the sloped region and the second base region, and is spaced apart from the first electrode layer. First and second reflective layers are on the first and second electrode layers, respectively, and overlap the sloped region.

Abstract: A tripod constant-velocity joint includes: an outer joint member having a cavity elongated in a longitudinal direction and three roller tracks; an inner joint member having a center body and three journals outwardly radially protruded from the center body; and three roller assemblies respectively coupled to the journal in a state of being respectively disposed in the roller tracks. The respective roller assembly comprises: an inner race which is connected to the journal and is provided with a first inner ball groove and a second inner ball groove on both lateral sides thereof; a first ball array and a second ball array respectively having a plurality of balls which are respectively disposed in the first inner ball groove and in the second inner ball groove; and a ball cage which restricts movements of the first ball array and the second ball array in a longitudinal direction thereof.

Abstract: A light emitting diode display device is provided.

Abstract: A method of manufacturing a semiconductor light emitting device may include: forming a buffer layer on a substrate; forming a protective layer on the buffer layer; performing heat treatment on a stacked structure of the substrate, the buffer layer, and the protective layer; removing the protective layer; and forming a light emitting structure on the buffer layer.

Abstract: A semiconductor light emitting device includes a light emitting stack including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, a plurality of holes through the second conductive semiconductor layer and the active layer, a trench extending along an edge of the light emitting stack, the trench extending through the second conductive semiconductor layer and the active layer, and a reflective metal layer within the plurality of holes and within the trench.

Abstract: A light emitting device package includes a package substrate and a submount on the package substrate. An upper surface of the submount includes a central region, first and second base regions spaced from the package substrate, relative to the central region, and a sloped region between the central region and the first and second base regions. A light emitting device chip is in the central region. A first electrode layer is between the central region and the light emitting device chip and extends onto the sloped region and the first base region. A second electrode layer is between the central region and the light emitting device chip, extends onto the sloped region and the second base region, and is spaced apart from the first electrode layer. First and second reflective layers are on the first and second electrode layers, respectively, and overlap the sloped region.

Abstract: An ultraviolet semiconductor light emitting device includes a semiconductor stack, a trench, a filling insulator, and first and second electrodes. The semiconductor stack includes first and second conductivity-type semiconductor layers and an active layer therebetween that includes an AlGaN semiconductor material. The trench extends through the second conductivity-type semiconductor layer and the active layer to the first conductivity-type semiconductor layer and has a first width. The filling insulator fills the trench such that the filling insulator extends at least through the active layer in the trench and includes of an insulating material having a particular refractive index. The first electrode is connected to the first conductivity-type semiconductor layer, and the second electrode is connected to the second conductivity-type semiconductor layer.

Abstract: A method for fabricating a nitride semiconductor thin film includes preparing a first nitride single crystal layer doped with an n-type impurity. A plurality of etch pits are formed in a surface of the first nitride single crystal layer by applying an etching gas thereto. A second nitride single crystal layer is grown on the first nitride single crystal layer having the etch pits formed therein.

Abstract: A method of fabricating a nitride semiconductor light emitting device is provided. The method includes growing a first group-III-nitride semiconductor layer on a substrate, the first group-III-nitride semiconductor layer having a top surface formed as a group-III-rich surface exhibiting a group-III-polarity and a bottom surface formed as a N-rich surface exhibiting a N-polarity. The method further includes selectively etching a N-polarity region in the top surface of the first group III nitride semiconductor layer, forming a second group III nitride semiconductor layer on the first group III nitride semiconductor layer to fill the etched N-polarity region and forming a light emitting structure including first and second conductivity type nitride semiconductor layers and an active layer on the second group III nitride semiconductor layer.

Abstract: A method for fabricating a nitride semiconductor thin film includes preparing a first nitride single crystal layer doped with an n-type impurity. A plurality of etch pits are formed in a surface of the first nitride single crystal layer by applying an etching gas thereto. A second nitride single crystal layer is grown on the first nitride single crystal layer having the etch pits formed therein.