Abstract: Two methods are presented in order to properly compensate the changes of the optical characteristics, which are caused by the optical path length change. First, a path length compensation method in which the additional optical path length, equivalent to the dicing kerf width of the substrate, is added onto the diced-to-be waveguide part of the AWG chip during the waveguide design process and fabrication process so that the compensated optical path length is maintained even after dicing. In addition, a position compensation method is provided in which an additional waveguide is added at the position shifted by a distance equivalent to the kerf width of the substrate such that the additional waveguide undergoes the minimized path length change after dicing is performed.

Abstract: Two methods are presented in order to properly compensate the changes of the optical characteristics, which are caused by the optical path length change. First, a path length compensation method in which the additional optical path length, equivalent to the dicing kerf width of the substrate, is added onto the diced-to-be waveguide part of the AWG chip during the waveguide design process and fabrication process so that the compensated optical path length is maintained even after dicing. In addition, a position compensation method is provided in which an additional waveguide is added at the position shifted by a distance equivalent to the kerf width of the substrate such that the additional waveguide undergoes the minimized path length change after dicing is performed.

Abstract: An optical waveguide chip includes an output waveguide connected to an optical fiber, an optical fiber array module, or another optical waveguide chip. The output waveguide has a coupling cross-section wider than the core of the optical fiber, the core of an optical fiber of the optical fiber array module, and the waveguide of the other optical waveguide, respectively. The cross-section width of the output waveguide of the optical waveguide chip gradually increases toward an end of the waveguide with a slant angle of 10° or less. Therefore, when the optical waveguide chip is connected to the optical fiber, the optical fiber array module, or the other optical waveguide chip during packaging of an optical waveguide device, an offset of the optical axis of about ±20% of the width of the waveguide guide is allowable.

Abstract: An optical fiber array connector and a method for fabricating the optical fiber array connector are disclosed. The disclosed optical fiber array connector an upper base plate and a lower base plate each being provided at a main surface thereof, in a desired region, with a plurality of first grooves each extending throughout the base plate in a direction corresponding to a longitudinal direction of an optical fiber to be mounted therein, and in regions other than the region where the first grooves are arranged, with a plurality of second grooves each extending throughout the base plate in a direction corresponding to a longitudinal direction of an alignment pin to be inserted therein, the upper and lower base plates being bonded to each other in such a fashion that the first and second grooves of the upper base plate face those of the lower base plate, respectively.

Abstract: A metal coated optical fiber array module including a metal coated optical fiber array, an arranging substrate having arranging grooves for loading the optical fiber array, wherein a metal is coated on the upper surface including the arranging grooves and the optical fiber array loaded into the arranging grooves is united therewith through the medium of the metal, and a cover for protecting and fixing the optical fiber array loaded into the arranging grooves of the arranging substrate. It is preferable that the optical fiber array module further includes a planar substrate having holes into which the optical fiber array is to be inserted, wherein the optical fiber array loaded on the arranging substrate is inserted into the holes and united with the arranging substrate. After the optical fibers are loaded, the ends thereof are easily polished.

Abstract: A method for fabricating low-loss optically active device having an optical waveguide constructed of an optical waveguide core region (non-linear core region) necessitating the non-linear effect when waveguiding an optical signal, and an optical waveguide core region (linear core region) not necessitating the non-linear effect, the method includes method for fabricating an optically active device having an optical waveguide constructed of an optical waveguide core region (non-linear core region) necessitating the non-linear effect when waveguiding an optical signal, and an optical waveguide core region (linear core region) not necessitating the non-linear effect, the method includes the steps of: forming a lower clad layer having a refractive index lower than the material of the waveguide core regions and optical transparency on a substrate, forming a linear optical polymer layer on the lower clad layer by coating linear optical polymer having a refractive index lower than the material of the lower clad layer

Abstract: A method of fabricating a planar optical waveguide in one chamber, comprising the steps of depositing a cladding layer and a core layer on a substrate, depositing an etch mask layer on the core layer, and forming a photoresist pattern on the etch mask layer. An etch mask pattern is formed by etching the etch mask layer according to the photoresist pattern using a first gas which reacts with the material of the etch mask layer, and removing the first gas. An optical waveguide is formed by etching the core layer according to the etch mask pattern using a second gas which reacts with the material of the core layer in the same chamber as the chamber where the above steps were performed, and removing the photoresist pattern and the second gas.

Abstract: An apparatus and a method for combining an optical waveguide and optical fibers are provided.

Abstract: The present invention includes a pigtailing method between an optical waveguide device and an optical fiber array module, comprising the steps of preparing the optical waveguide device having optical waveguides of n1 input ports and n2 output ports on the lateral surface of a substrate, wherein n1 and n2 are integers equal to or greater than 1, aligning the optical fiber array module having optical fibers arranged at equal distances between the input ports and between the output ports, to the input and output ports of the optical waveguide device, and attaching the aligned optical fiber array module to the lateral surface of the optical waveguide device. Since only one attachment process of the optical fiber array module to the optical waveguide device is required, the fabrication cost can be reduced.

Abstract: An optical fiber passive alignment apparatus for passively aligning optical fibers with input/output optical waveguides of an integrated optical device includes an optical fiber array block on which the optical fibers are mounted with a uniform spacing and having alignment grooves parallel to the optical fibers, and an optical fiber fixing plate for fixing the mounted optical fibers to a substrate; an optical waveguide device chip having an input/output optical waveguide array consisting of optical waveguides corresponding to the optical fibers, for coupling with the optical fibers, and alignment holes; and an alignment platform having first alignment ridges separated by the same spacing as the alignment grooves, for coupling with the alignment grooves, alignment bumps in positions corresponding to the alignment holes, for coupling with the alignment holes, and a space between the first alignment ridges for preventing the optical fiber plate of the optical fiber block array from contacting the alignment platf

Abstract: A modal evolution coupler having a low-loss or non-loss effect when a transmitted light passes through an optical fiber and is output via an expanding element, includes: a first optical fiber which gradually, thermally expands a core to evolute the mode of a transmitted light, a second optical fiber which gradually, thermally expands a core to evolute the mode of a transmitted light, an expanding element which is placed between the first and second optical fibers, and is formed of an ultraviolet curing resin, and has ends whose section areas are equal to the respective ends of the first and second expanded optical fibers when an ultraviolet ray is incident thereon and cured, and includes expanded portions which are each expanded over a predetermined expansion distance starting from a connecting portion to the first or second optical fiber and a middle portion keeping its size constant for a predetermined length between the expanded portions of the first and second optical fibers, and does not move in the expa

Abstract: An optical waveguide device fabricating method which requires that a lower clad layer is formed on the surface of a glass substrate, a metal layer is formed on the lower clad layer, and a metal pattern is formed by selectively etching the metal layer, for forming a waveguide core therein. Then, an optical polymer layer is formed in the metal pattern, the optical polymer layer in a metal-free portion of the metal pattern is cured by irradiating UV light onto the lower surface of the substrate, and the waveguide core is formed by removing the other portion of optical polymer layer except for the cured portion thereof and the metal layer. Finally, an upper clad layer is formed on the lower clad layer and the waveguide core.

Abstract: A low-loss optically active device is provided by forming a lower clad layer using linear polymer on a substrate capable of transmitting ultraviolet (UV) light, forming a non-linear polymer core region of a waveguide region; forming a linear polymer core region on opposite sides of the non-linear core region, and forming an upper clad layer on the lower clad layer and linear and non-linear core regions of the waveguide region. The waveguide is formed using non-linear polymer only at the region where the non-linear effect such as optical modulation or optical switching occurs, and is formed using linear polymer at the remaining regions, thereby minimizing the overall waveguiding loss of the device.

Abstract: A hybrid optical waveguide having linear and curved sections through which optical signals pass, includes: a planar substrate layer; a lower cladding layer formed of a material having optical transparency in a predetermined range of optical communication wavelengths, on the planar substrate layer; a core layer formed on the lower cladding layer where the optical waveguide is formed, the waveguide constituted of the linear section formed of a first optical polymer having a higher refractive index than the lower cladding layer and the curved section formed of a second optical polymer having a higher refractive index than the first optical polymer; and an upper cladding layer formed of a material having a lower refractive index than the first and the second optical polymers, surrounding the waveguide core layer. The optical waveguide having the linear and curved sections has reduced traveling losses and optical fiber coupling losses, and minimizes the size of the waveguide cross-section.