Abstract: Provided are a transporter gene involved in the promotion or inhibition of Cd absorption by roots, a mutant gene thereof and a transporter protein thereof, as well as a rice plant in which Cd absorption is inhibited and a method for selecting and raising a Cd absorption-inhibiting rice plant, which are a gene encoding a transporter protein involved in the regulation of cadmium absorption, which contains the DNA nucleotide sequence shown in SEQ ID NO:2, a gene encoding a transporter protein involved in the regulation of cadmium absorption, which contains the DNA nucleotide sequence shown in SEQ ID NO:3, a gene encoding a transporter protein involved in the regulation of cadmium absorption, which contains the DNA nucleotide sequence shown in SEQ ID NO:4, and a transporter protein involved in the regulation of cadmium absorption, which contains the amino acid sequence of SEQ ID NO:1.

Abstract: An optical assembly that installs red, green, blue laser diodes (LDs) within a single package is disclosed. The LDs are mounted on a base via respective sub-mounts. Light emitted from the LDs is collimated by collimating lenses and multiplexed by two wavelength filters so as to align optical axes of the light. The multiplexed light has an axis substantially leveled with the axes of the red, green, and blue light measured from the top of the base.

Abstract: An optical module having a substrate and an electrical connector whose terminals are precisely aligned with pads on the substrate is disclosed. The electrical connector provides upper and lower terminals, while, the substrate provides upper and lower pads each having a V-shaped cut opened for a direction along which the upper and lower terminals are slide. As the electrical connector is assembled with the substrate, the terminals slide along the edge of the V-shaped cut and slide onto the pads at the bottom of the V-shaped cut, which automatically and precisely aligns the terminals with the pads.

Abstract: An optical device that emits white light by mixing three or four light each having a specific color is disclosed. The optical device includes the alignment substrate having a first type of grooves each setting an optical fiber therein and a second type of a groove setting all fibers collectively. Between two type of grooves, all fibers are free from grooves to facilitate the assemble of the fibers.

Abstract: An optical module with an arrangement is disclosed in which the module has the LD, the TEC, and the lens with the lens carrier also mounted on the TEC. The signal light from the LD is concentrated by the lens and reflected by the mirror each assembled with the lens carrier mounted on the TEC. The TEC is mounted on the bottom metal that covers the bottom of the ceramic package, the first layer of which is widely cut to set the TEC therein. The FPC is coupled in at least two edges of the first ceramic layer left from the cut.

Abstract: An optical module is disclosed, in which the optical module installs a plurality of optical devices each optically coupling with a single fiber in the focused beam coupling system. The optical module includes a condenser lens, and respective optical devices install an individual lens. One of the beam waists of the condenser lens locates on the end of the optical fiber and the other of the beam waist locates on the outer wall of the coupling unit to which the optical devices are attached. One of the beam waists of the individual lens in the optical device substantially aligns with the other beam waist of the condenser lens, while, the other of the beam waist of the individual lens aligns at the semiconductor optical device.

Abstract: A light source device includes a single optical waveguide, a plurality of optical sub-assemblies, and an assembly holder. The optical waveguide includes a core area extending along a predetermined axis, a cladding area covering a periphery of the core area, and a first end face extending along a plane intersecting the predetermined axis. The assembly holder has an inner surface supporting the optical sub-assemblies so that the optical sub-assemblies are respectively arranged on a plurality of reference lines and optically coupled to the first end face of the optical waveguide. Each optical sub-assembly includes a semiconductor light-emitting element having a light-emitting surface optically coupled to the first end face of the optical waveguide, and a support member on which the semiconductor light-emitting element is mounted. The reference lines extend in different directions from one point on a predetermined axis of the core area to the cladding area.

Abstract: A bi-directional optical module with an improved optical crosstalk between the transmitter unit and the receiver unit is disclosed. The optical module provides the LD, the PD, the WDM filter secured with the block, and the package with the co-axial shape. The block provides a slant surface, where the WDM filter is secured thereon, the bottom surface facing the PD mounted on the package, and an aperture connecting the slant surface and the bottom surface. The PD is enclosed within a space formed by the bottom surface and the primary surface, which electrically and optically isolates the PD from the LD.

Abstract: An optical device that emits white light by mixing three or four light each having a specific color is disclosed. The optical device includes the alignment substrate having a first type of grooves each setting an optical fiber therein and a second type of a groove setting all fibers collectively. Between two type of grooves, all fibers are free from grooves to facilitate the assemble of the fibers.

Abstract: An optical receptacle that enhances the optical coupling tolerance is disclosed. The optical receptacle of the invention provides, in stead of the coupling fiber installed in a conventional optical receptacle, a glass member with a diameter substantially equal to the diameter of the external fiber. The glass member, which is held by the support, provides a convex surface that abuts against the top of the external ferrule and another surface inclined with the optical axis to prevent the light reflected thereat from returning the optical device. The glass member has a substantially homogeneous distribution in the refractive index thereof; accordingly, the fluctuation in the optical coupling with the external ferrule may be reduced.

Abstract: The bi-directional optical module, which installs the receiver and the transmitter within one package, is disclosed with an improved optical crosstalk. The optical module provides a lens, a WDM filter and a photodiode (PD) on an axis of the single mode fiber coupled with the module, while, a laser diode (LD) in a position perpendicular to the optical axis. The WDM filter provides a multi-layered optical film on a primary surface and an edge in a side far from the LD and the (PD) makes an obtuse angle to the primary surface so as to prevent light from the LD and reflected at this edge from entering the PD.

Abstract: An optical module with an arrangement is disclosed in which the module has the LD, the TEC, and the lens with the lens carrier also mounted on the TEC. The signal light from the LD is concentrated by the lens and reflected by the mirror each assembled with the lens carrier mounted on the TEC. The TEC is mounted on the bottom metal that covers the bottom of the ceramic package, the first layer of which is widely cut to set the TEC therein. The FPC is coupled in at least two edges of the first ceramic layer left from the cut.

Abstract: A bi-directional optical subassembly (BOSA) is disclosed. The BOSA of the present invention provides first and second optical devices, a WDM filter and the body that is configured to secure two optical devices and to install the WDM filter. The body has a cylindrical shape with a large bore, a small bore and a joint bore connecting two bores. The WDM filter is attached to the tapered surface of the joint bore.

Abstract: A bi-directional optical subassembly (BOSA) with a unique arrangement to set the WDM filter is disclosed. The BOSA includes the stem and the lens cap. The stem mounts both the LD and the PD. While, the lens cap provides, in addition to the condenser lens, a structure to set the WDM filter in a top center thereof. The WDM filter is set in the lens cap with a present angle to the primary surface of the stem when the lens cap is fixed to the stem. Assembling the lens cap with the stem, the relative optical alignment between the LD, the PD and the WDM filter is performed.

Abstract: An optical module with a ferrule assembly able to be easily produced is disclosed. The ferrule with a tubular shape provides first to third bores. The first bore receives the optical fiber with a sheath, the second bore receives only the glass core of the fiber, which is obtained by removing the sheath, and the third bore has a diameter substantially equal to the outer diameter of the glass core of the fiber. A resin is filled in the gap between the sheath and the third bore, and in the gap between the glass core of the fiber and the second bore. The tip of the glass core is tilted with the axis and protrudes from the end surface of the ferrule.

Abstract: A bi-directional optical module with an arrangement to install WDM filters easily and precisely is disclosed. The optical module of the invention provides two or more optical devices, a filter unit installed with one or more WDM filters, and a coupling unit. One end of the filter unit assembles the coupling unit, while the other end thereof assembled a specific optical device. Rest optical devices are assembled with the filter unit such that their optical axes are perpendicular to the axis connecting the coupling unit with the specific optical device. The WDM filters are set on the inner of the filter bore such that the angle thereof is adjusted by rotating it as coming the edges of the WDM filter in contact with the inner wall.

Abstract: An optical receptacle that enhances the optical coupling tolerance is disclosed. The optical receptacle of the invention provides, in stead of the coupling fiber installed in a conventional optical receptacle, a glass member with a diameter substantially equal to the diameter of the external fiber. The glass member, which is held by the support, provides a convex surface that abuts against the top of the external ferrule and another surface inclined with the optical axis to prevent the light reflected thereat from returning the optical device. The glass member has a substantially homogeneous distribution in the refractive index thereof; accordingly, the fluctuation in the optical coupling with the external ferrule may be reduced.

Abstract: A bi-directional optical module with an improved optical crosstalk between the transmitter unit and the receiver unit is disclosed. The optical module provides the LD, the PD, the WDM filter secured with the block, and the package with the co-axial shape. The block provides a slant surface, where the WDM filter is secured thereon, the bottom surface facing the PD mounted on the package, and an aperture connecting the slant surface and the bottom surface. The PD is enclosed within a space formed by the bottom surface and the primary surface, which electrically and optically isolates the PD from the LD.

Abstract: A nicotianamine synthase is isolated and purified. Then the gene of this enzyme is cloned and the base sequence and amino acid sequence thereof are determined. This gene is employed in constructing plants, in particular, grass plants highly tolerant to iron-deficiency. A nicotianamine synthase involved in the mugineic acid biosynthesis pathway; the amino acid sequence thereof; a gene encoding the same; a vector containing this gene; cells transformed by the vector; a process for producing nicotianamine by using the same; plants transformed by the gene encoding the nicotianamine synthase; and an antibody against the nicotianamine syntase.

Abstract: A bi-directional optical subassembly (BOSA) is disclosed. The BOSA of the present invention provides first and second optical devices, a WDM filter and the body that is configured to secure two optical devices and to install the WDM filter. The body has a cylindrical shape with a large bore, a small bore and a joint bore connecting two bores. The WDM filter is attached to the tapered surface of the joint bore.