Abstract: A keypad assembly including a light guide plate, a keypad, and reflective layers is disclosed. The light guide plate includes reflective patterns that are locally formed on the bottom surface of the light guide plate to reflect a part of light going into the light guide plate to the top surface of the light guide plate. The keypad includes a pad that is in the shape of a box whose bottom is opened by sidewalls and surrounds the remaining portions of the light guide plate except for the bottom surface of the light guide plate and at least one key button placed on the top surface of the pad and outputting light reflected from the reflective patterns to their outside. The reflective layers are formed at the sidewalls of the pad facing the sides of the light guide plate to reflect light irradiated from the sides of the light guide plate back to the sides of the light guide plate.

Abstract: A keypad assembly includes a light guide plate adapted to transmit light and comprising a supporting portion and an elastic portion made of different material than material of the supporting portion, at least one key button disposed on the side of the light guide plate where a first surface of the light guide plate is located, and at least one reflection pattern locally formed on the light guide plate and adapted to reflect light transmitted into the light guide plate toward the key button. The elastic portion is disposed below the key button.

Abstract: A keypad includes a light guide panel, the interior of which light propagates through, a film positioned on the upper surface of the light guide panel and having at least one key button positioned on the upper surface thereof, and at least one reflective pattern fixedly positioned with respect to the light guide panel to reflect a part of the light, which propagates through the interior of the light guide panel, towards the key button.

Abstract: A keypad includes a light guide panel, the interior of which light propagates through; at least one key button positioned on the upper surface of the light guide panel; and at least one reflective pattern fixedly positioned with respect to the light guide panel to reflect a part of the light, which propagates through the interior of the light guide panel, towards the key button.

Abstract: A keypad assembly includes a keypad having at least one elastic layer and at least one key button on the elastic layer, a waveguide for transmitting and guiding light therethrough, the waveguide being placed below the elastic layer and having at least one reflection pattern to reflect light toward a respective key button, and a switch substrate under the waveguide and having at least one switch corresponding to the respective key button.

Abstract: Disclosed is a keypad which can realize uniform and bright illumination, small power consumption and low manufacturing cost. The keypad includes a light guide layer through which light travels, at least one key button disposed on an upper surface of the light guide layer, a lower elastic layer disposed on a lower surface of the light guide layer, located opposite the upper surface, and at least one reflective pattern formed on the light guide layer and partially reflecting light traveling through the light guide layer toward the key button.

Abstract: An optical filter includes a body of a polyhedron structure in which a recess having a predetermined depth from one side surface is exposed on a front surface and a rear surface and a multi-layer thin film which is deposited on the front surface of the body to cover an exposed portion of the recess of the body.

Abstract: A planar light wave circuit is disclosed, which comprises: a first waveguide for receiving optical signals from an outside; a second waveguide having a first end surface and a second end surface, so that lights outputted from the first waveguide are partially reflected by the first end surface and are partially incidented into the first end surface and then outputted through the second end surface; a third waveguide for receiving the light reflected by the first end surface; and a common region bordering each end surface of the first to the third waveguides and having an index of refraction different from an index of refraction of the second waveguide.

Abstract: Disclosed is a method for fabricating planar light waveguide circuits, wherein the circuit has a structure that includes a substrate comprised of a core and under-clad layers, an optical circuit, and a plurality of arrayed waveguides coupled thereon. More specifically, the method includes the steps of layering a hard layer on the core layer for forming a mask pattern of the planar light waveguide circuit; forming the mask pattern on the hard layer; layering a photoresist layer on a branch of the optical circuit and the arrayed waveguides of the mask pattern; forming a vertical taper structure on the photoresist layer using a gray scale mask; and, etching the core layer using the photoresist layer with the vertical taper structure and the mask pattern.

Abstract: Disclosed are a flip-chip bonding structure for improving the vertical alignment of an optical device relative to a PLC and a flip-chip bonding method for achieving this structure. The flip-chip bonding structure includes: a semiconductor substrate; a lower-clad layer formed on the upper surface of the semiconductor substrate, wherein the lower-clad layer is depressed on a designated area for mounting an optical device; vertical alignment structures formed on a part of the upper surface of the depressed area of the lower-clad layer and determining a vertical alignment position of the optical device on the semiconductor substrate; electrodes formed on another part of the upper surface of the depressed area of the lower-clad layer; a solder bump formed on the upper surfaces of the electrodes; and, an optical device bonded to the substrate by a flip-chip bonding method using the solder bump.

Abstract: An optical hybrid module and method of manufacture includes a plurality of optical devices integrated on an optical waveguide substrate. The structure helps to reduce optical crosstalk among the plurality of optical devices caused by reflections of leakage lights within the optical hybrid module. The optical hybrid module includes a substrate, an optical waveguide formed on the substrate for performing transmission of optical signals, a plurality of optical devices mounted on the substrate to be optically coupled with the optical waveguide, and a light blocking layer formed to have an inclined profile at opposite sides of an end surface of an optical coupling portion centrally provided in the optical waveguide. The light blocking layer serves to prevent light from entering the optical devices, through regions other than the optical waveguide.

Abstract: A bidirectional optical communication module capable of precisely controls the location of a reflective surface of the reflector is disclosed. The module includes: an input waveguide for inputting an optical signal; a reflector including a reflective groove formed by a photolithography process such that the groove is extended from one end surface of the bidirectional optical communication module to a connection waveguide, and a reflective layer formed on a base surface formed in the reflective groove so as to reflect the optical signal inputted from the input waveguide; and an output waveguide for outputting the optical signal reflected by the reflector. The connection waveguide is configured to transmit the optical signal inputted from the input waveguide to the reflector and output the optical signal reflected by the reflector to the output waveguide.

Abstract: A planar light wave circuit is disclosed, which comprises: a first waveguide for receiving optical signals from an outside; a second waveguide having a first end surface and a second end surface, so that lights outputted from the first waveguide are partially reflected by the first end surface and are partially incidented into the first end surface and then outputted through the second end surface; a third waveguide for receiving the light reflected by the first end surface; and a common region bordering each end surface of the first to the third waveguides and having an index of refraction different from an index of refraction of the second waveguide.

Abstract: Disclosed are a flip-chip bonding structure for improving the vertical alignment of an optical device relative to a PLC and a flip-chip bonding method for achieving this structure. The flip-chip bonding structure includes: a semiconductor substrate; a lower-clad layer formed on the upper surface of the semiconductor substrate, wherein the lower-clad layer is depressed on a designated area for mounting an optical device; vertical alignment structures formed on a part of the upper surface of the depressed area of the lower-clad layer and determining a vertical alignment position of the optical device on the semiconductor substrate; electrodes formed on another part of the upper surface of the depressed area of the lower-clad layer; a solder bump formed on the upper surfaces of the electrodes; and, an optical device bonded to the substrate by a flip-chip bonding method using the solder bump.

Abstract: A wavelength-division-multiplexing system is disclosed and includes: a semiconductor-amplification section for amplifying each inputted channel with amplification factors corresponding to the compensation signals received therein; a multiplexer for multiplexing a plurality of channels inputted from the semiconductor-amplification section and outputting the multiplexed signals; an optical-detection section for splitting a part of the multiplexed optical signals inputted from the multiplexer, demultiplexing the split optical signals into a plurality of channels, converting each of the demultiplexed channels into corresponding electric signals, and outputting the electric signals; and, a control section calculating the pertinent intensity deviations by comparing each intensity of the electric signals inputted from the optical-detection section with a preset reference intensity and outputting compensation signals for compensating the intensity deviation of each channel to the semiconductor-amplification section.

Abstract: Disclosed is a method for manufacturing a tapered optical waveguide through which waveguides of different sizes are connected with each other optically. In the method, a photo-resist pattern having an inclined profile is formed on the core layer by means of a gray-scale mask, then the profile of the tapered waveguide can be precisely controlled by controlling the profile of the photo-resist pattern and the etching-selection ratio between the photo-resist and the core layer.

Abstract: Disclosed are a flip-chip bonding structure for improving the vertical alignment of an optical device relative to a PLC and a flip-chip bonding method for achieving this structure. The flip-chip bonding structure includes: a semiconductor substrate; a lower-clad layer formed on the upper surface of the semiconductor substrate, wherein the lower-clad layer is depressed on a designated area for mounting an optical device; vertical alignment structures formed on a part of the upper surface of the depressed area of the lower-clad layer and determining a vertical alignment position of the optical device on the semiconductor substrate; electrodes formed on another part of the upper surface of the depressed area of the lower-clad layer; a solder bump formed on the upper surfaces of the electrodes; and, an optical device bonded to the substrate by a flip-chip bonding method using the solder bump.

Abstract: Disclosed is a method for fabricating planar light waveguide circuits, wherein the circuit has a structure that includes a substrate comprised of a core and under-clad layers, an optical circuit, and a plurality of arrayed waveguides coupled thereon. More specifically, the method includes the steps of layering a hard layer on the core layer for forming a mask pattern of the planar light waveguide circuit; forming the mask pattern on the hard layer; layering a photoresist layer on a branch of the optical circuit and the arrayed waveguides of the mask pattern; forming a vertical taper structure on the photoresist layer using a gray scale mask; and, etching the core layer using the photoresist layer with the vertical taper structure and the mask pattern.

Abstract: Disclosed is a method for manufacturing a tapered optical waveguide through which waveguides of different sizes are connected with each other optically. In the method, a photo-resist pattern having an inclined profile is formed on the core layer by means of a gray-scale mask, then the profile of the tapered waveguide can be precisely controlled by controlling the profile of the photo-resist pattern and the etching-selection ratio between the photo-resist and the core layer.

Abstract: Disclosed are a flip-chip bonding structure for improving the vertical alignment of an optical device relative to a PLC and a flip-chip bonding method for achieving this structure. The flip-chip bonding structure includes: a semiconductor substrate; a lower-clad layer formed on the upper surface of the semiconductor substrate, wherein the lower-clad layer is depressed on a designated area for mounting an optical device; vertical alignment structures formed on a part of the upper surface of the depressed area of the lower-clad layer and determining a vertical alignment position of the optical device on the semiconductor substrate; electrodes formed on another part of the upper surface of the depressed area of the lower-clad layer; a solder bump formed on the upper surfaces of the electrodes; and, an optical device bonded to the substrate by a flip-chip bonding method using the solder bump.