Abstract: An optical wave guide has a lower cladding layer formed on a substrate, and a Y-branched optical wave guide arranged on the lower cladding layer. The optical wave guide is covered with an upper cladding layer. Curved portions of the optical wave guide are tapered at the external circumferential sides and formed into a trapezoidal cross sectional shape, and effective refractive index of the optical wave guide is made small at the tapered external circumferential sides. Meanwhile, end surfaces of the optical wave guide are formed into a rectangular shape, thereby joint efficiency with optical fibers is increased.

Abstract: The spacers 3 and 4 and the recess is formed on the supporting substrate 2 to support the upper cladding layer 7. The intermediate surface 22 and 23 lower than the top surface of the spacers 3 and 4 and higher than the inner bottom surface of the recess is formed on the supporting substrate 2. Each of the height between the top surface of the spacers 3 and 4 and the intermediate surfaces 22 and 23, and the height between the intermediate surfaces 22 and 23 and the inner bottom surface of the recess of the second substrate 2 becomes thin compared with the total thickness of the lower cladding layer. Thus, when the resin for the lower cladding layer 9 is cured to shrinkage, the inner stress in the resin is dispersed and the occurrence of the wrinkle 12 and the void decreases.

Abstract: An oxide film is formed on an end surface of a waveguide which includes an under cladding, a core and a over cladding. An end surface of a fiber guide holding an optical fiber is coupled the end surface of the waveguide formed the oxide film with a glue. It is preferable that the oxide film is SiOx (1?x?1.5). This oxide film has a composition ratio of an oxygen atom smaller than the stable composition, and thus it is easy for OH radicals to appear on the surface of the oxide film. Such OH radicals bond chemically with the resin of the waveguide and the glue. Thus, an adhesive strength between the waveguide and the fiber guide is improved.

Abstract: In the upper face of a lower clad layer, a core trench is formed having a cross-sectional trapezoidal shape having a narrow bottom face and a wide upper face, a core is formed within the core trench, and an upper clad layer is formed at the upper face of the core for sealing. The bottom face of the core trench becomes a low refractive index layer having a refractive index smaller than the lower clad layer. The substantive difference of refractive index between the core and the lower clad layer is thus increased.

Abstract: A second light guide is formed by filling, with a core material, a groove that is formed on the top surface of a reception-side substrate. A first light guide is formed by filling, with a core material, a groove that is formed on the bottom surface of a sending-side substrate. The reception-side substrate and the sending-side substrate are bonded to each other with a cladding layer interposed in between so that the second light guide and the first light guide are isolated from each other optically.

Abstract: An optical multiplexer/demultiplexer having a high isolation characteristic, a small polarization dependency and capable of being reduced in size is disclosed. An end portion of a core and an end portion of a core are arranged in opposed relation to each other with a thin-film filter interposed therebetween. The end portion of the core far from the filter and the end portion of the core far from the filter are arranged in substantially parallel to each other. The core is arranged in such a manner as to branch from the filter-side end portion of the core and to be optically coupled with the core. The end portion of the core near to the filter and the end portion of the core near to the filter are curved. The end portion of the core near to the filter is curved in a manner protruded toward the core. The end portion of each of the core and the core far from the filter reaches an end of an optical waveguide, and the end portion of the core far from the filter reaches a side of the optical waveguide.

Abstract: Light of wavelengths &lgr;2 and &lgr;3 (&lgr;2<&lgr;3) is propagated in a first core. The light emitted form the first core is divided at a filter. That is, the light of the wavelength &lgr;2 transmits through the filter and is made incident onto a third core while the light of the wavelength &lgr;3 is reflected from a filter and is made incident onto a second core. The second core has a sectional area which works in a single mode for the light of the wavelength &lgr;3 and works in a multiple mode for the light of the wavelength &lgr;2. It is therefore possible to prevent noise or stray light in an optical multiplexer/demultiplexer.

Abstract: In an optical waveguide device, a rectangle, which uses a filter insertion groove as its diagonal line and uses points on filter insertion grooves adjacent to the above filter insertion groove as its apexes, is assumed as a unit rectangle, and the size of the optical waveguide device is set to an integer multiple of the unit rectangle. In this case, even if filter insertion grooves are formed in a state in which a plurality of the optical waveguide devices are disposed in matrix, the respective optical waveguide devices can be formed in the same shape. Further, the filter insertion grooves formed to the respective optical waveguide devices do not divide portions other than the target portion of other optical waveguide devices. Therefore, the manufacturing processes of the optical waveguide device can be simplified and are suitable for mass production, and manufacturing cost can be suppressed thereby.

Abstract: A method of manufacturing an optical waveguide device includes providing an optical fiber guide for fixing an optical fiber and optical element placing portions for providing element mounting benches outside a waveguide fixing region of a silicon substrate. A metallic thin film is formed outside the waveguide fixing region of the silicon substrate. After an optical waveguide substrate is bonded to a whole of an upper surface of the silicon substrate through a bonding resin which will become an upper cladding layer, the optical waveguide substrate is diced along an edge of the waveguide fixing region, and the optical waveguide substrate outside the waveguide fixing region is removed to expose the optical fiber guide and the optical element placing portions.

Abstract: An optical wave guide device is manufactured by bonding an optical wave guide to an optical modulator through an upper cladding layer. The optical wave guide includes a glass substrate, a lower cladding layer and cores, and the optical modulator includes elements (heaters), which are disposed on the lower surface of a glass substrate, for modulating the light propagating in the cores, and electrodes and wire bond pads which are disposed on the front surface thereof. The elements are connected to the electrodes via through-holes. With this arrangement, there can be provided an optical waveguide device, in which cores are not degraded in manufacturing processes and elements for modulating the light propagating in the cores are unlikely to be exfoliated.

Abstract: In an optical waveguide device, a rectangle, which uses a filter insertion groove as its diagonal line and uses points on filter insertion grooves adjacent to the above filter insertion groove as its apexes, is assumed as a unit rectangle, and the size of the optical waveguide device is set to an integer multiple of the unit rectangle. In this case, even if filter insertion grooves are formed in a state in which a plurality of the optical waveguide devices are disposed in matrix, the respective optical waveguide devices can be formed in the same shape. Further, the filter insertion grooves formed to the respective optical waveguide devices do not divide portions other than the target portion of other optical waveguide devices. Therefore, the manufacturing processes of the optical waveguide device can be simplified and are suitable for mass production, and manufacturing cost can be suppressed thereby.

Abstract: An optical wave guide has a lower cladding layer formed on a substrate, and a Y-branched optical wave guide arranged on the lower cladding layer. The optical wave guide is covered with an upper cladding layer. Curved portions of the optical wave guide are tapered at the external circumferential sides and formed into a trapezoidal cross sectional shape, and effective refractive index of the optical wave guide is made small at the tapered external circumferential sides. Meanwhile, end surfaces of the optical wave guide are formed into a rectangular shape, thereby joint efficiency with optical fibers is increased.

Abstract: An optical element that realizes light path conversion of transmitting light at low loss, allows easy incorporation of functions such as light convergence or the like, and can be easily made into a compact size includes upper and lower main surfaces of a light path converting element of a plane shape are facing each other, and a light incoming surface and a light outgoing surface are adjacent surfaces at about 90 degrees. A curved light path converting surface is formed so as to face the light incoming surface and the light outgoing surface. Light coming in from the light incoming surface repeats full reflection between the upper main surface and the lower main surface and goes on, and is reflected by the light path converting surface, thereby the light path thereof is converted, and light is ejected from the light outgoing surface.

Abstract: A light emission device includes a light emitter, a light reflection member, and a resin sealing the light emitter by covering the light reflection member and the light emitter, in which light deviated from a predetermined front region in the light emitted from the light emitter is totally reflected by a boundary surface of the resin to be forwardly emitted by the light reflection member, and the emitter is thermally contacted with the reflection member to dissipate the heat generated from the light emitter.

Abstract: To provide an optical wave guide that may be produced by reproduction method in easy and simple manner, and has a structure that prevents light signal in its inside from leaking out from core, and a method for producing the same optical wave guide. A concave slot 3 for forming a core is formed on the upper surface of a cladding substrate 2. And on both sides of the concave slot 3, cavities 6 are formed via flat portions 5. An ultraviolet ray hardening type transparent resin 8 is applied onto the surface of the cladding substrate 2, thereafter the transparent resin 8 is pressed by a stamper 13. At this moment, a core 4 is formed in the concave slot 3 and excessive transparent resin 8 pressed between the stamper 13 and the flat portions 5 flows into cavities 6, as a result, it is possible to make the transparent resin 8 thin in a short time. Thereby, it is possible to make the transparent resin 8 left on the flat portions 5 into thickness and width enough to prevent light in the core 4 from leaking out.

Abstract: To couple a light emitted from aa transmitting light guide to an optical fiber with good efficiency, thereby reducing a coupling loss with the optical fiber. The light emitted from the transmitting light guide deviates from an NA of the optical fiber to prevent the loss from occurring. A groove 25 provided on an upper face of a receiving side substrate 22 is filled with a core material to form a receiving light guide 26. A groove 27 provided on a lower face of a transmitting side substrate 24 is filled with the core material to form a transmitting light guide 28 having a linear shape. The receiving side substrate 22 and the transmitting side substrate 24 are joined with a cladding layed interposed so as to optically separate the receiving light guide 26 and the transmitting light guide 28 each other.

Abstract: A second light guide is formed by filling, with a core material, a groove that is formed on the top surface of a reception-side substrate. A first light guide is formed by filling, with a core material, a groove that is formed on the bottom surface of a sending-side substrate. The reception-side substrate and the sending-side substrate are bonded to each other with a cladding layer interposed in between so that the second light guide and the first light guide are isolated from each other optically.

Abstract: A light emission device includes a light emitter, a light reflection member, and a resin sealing the light emitter by covering the light reflection member and the light emitter, in which light deviated from a predetermined front region in the light emitted from the light emitter is totally reflected by a boundary surface of the resin to be forwardly emitted by the light reflection member, and the emitter is thermally contacted with the reflection member to dissipate the heat generated from the light emitter.

Abstract: This invention improves the use efficiency of light emitted by a solid light emitter such as a light emitting diode, and realizes a desired directional pattern. On a front boundary surface of a mold resin 13 sealing a light emitter 12, there are formed a direct emission region 18 for emitting the light from the light emitter 12 and a total reflection region 19 for totally reflecting the light from the light emitter 12. The direct emission region 18 is convex lens-shaped. A light reflecting portion 20 having a concave mirror shape is disposed on a rear wall of the mold resin 13. A part of light emitted from the light emitter 12 is emitted forward by receiving an optical lens action when it passes through the direct emission region 18. Another part of the light emitted by from the light emitter 12 is totally reflected by the total reflection region 19, and is reflected by the light reflecting portion 20, and emitted forward from the total reflection region 19.

Abstract: Whether or not an object is present, the surface state of the object, the material constituting the object and the presence of scattering bodies are discriminated through a simple arrangement which includes a light-emitting element for projecting light upon an object to be sensed, and a polarization beam splitter upon which light reflected from the object (or light transmitted through or scattered from the object) impinges. Reflected light from the polarization beam splitter is received by a first light-receiving element, and transmitted light from the polarization beam splitter is received by a second light-receiving element. The aforesaid discrimination is performed on the basis of the value of S/P, S-P, S-kP or (S-P)/(S+P), where S and P represent light-reception signals from the first and second light-receiving elements, and k is a constant.