Abstract: An optical waveguide includes a clad layer, a core layer and a clad layer which are laminated together in this order from a lower side thereof. Within the core layer, a core portion and a side clad portion provided adjacent to the core portion so as to surround side surfaces of the core portion are formed. Further, a part of the side clad portion prevents a left side end of the core portion from being exposed outside. A mirror formation region is constituted from a region consisting of such a part of the side clad portion and a part of each of the clad layers located thereabove and therebelow. This mirror formation region is subjected to digging processing so that a concave portion is formed. An inner surface of this concave portion serves as the mirror. From the mirror, a material other than a material constituting the core portion, that is, a material constituting each of the clad layers and a material constituting the side clad portion are exposed.

Abstract: A substrate on which an optical element is mounted is provided, including: an optical element; an optical circuit substrate which is formed by an optical waveguide layer having a core portion and cladding portions; and an electrical circuit substrate on which is provided a mounting portion that is used for mounting the optical element, wherein the optical element is mounted on the electrical circuit substrate via the optical circuit substrate and wherein the optical circuit substrate has an optical element mounted thereon and is provided with a receptor structure having a conductive portion that conducts electricity between an electrode of the optical element and an electrode of the electrical circuit substrate.

Abstract: An optical waveguide includes a clad layer, a core layer and a clad layer which are laminated together in this order from a lower side thereof. Within the core layer, a core portion and a side clad portion provided adjacent to the core portion so as to surround side surfaces of the core portion are formed. Further, a part of the side clad portion prevents a left side end of the core portion from being exposed outside. A mirror formation region is constituted from a region consisting of such a part of the side clad portion and a part of each of the clad layers located thereabove and therebelow. This mirror formation region is subjected to digging processing so that a concave portion is formed. An inner surface of this concave portion serves as the mirror. From the mirror, a material other than a material constituting the core portion, that is, a material constituting each of the clad layers and a material constituting the side clad portion are exposed.

Abstract: A substrate on which an optical element is mounted is provided, including: an optical element; an optical circuit substrate which is formed by an optical waveguide layer having a core portion and cladding portions; and an electrical circuit substrate on which is provided a mounting portion that is used for mounting the optical element, wherein the optical element is mounted on the electrical circuit substrate via the optical circuit substrate and wherein the optical circuit substrate has an optical element mounted thereon and is provided with a receptor structure having a conductive portion that conducts electricity between an electrode of the optical element and an electrode of the electrical circuit substrate.

Abstract: A substrate on which an optical element is mounted is provided, including: an optical element; an optical circuit substrate which is formed by an optical waveguide layer having a core portion and cladding portions; and an electrical circuit substrate on which is provided a mounting portion that is used for mounting the optical element, wherein the optical element is mounted on the electrical circuit substrate via the optical circuit substrate and wherein the optical circuit substrate has an optical element mounted thereon and is provided with a receptor structure having a conductive portion that conducts electricity between an electrode of the optical element and an electrode of the electrical circuit substrate.

Abstract: A substrate on which an optical element is mounted is provided, including: an optical element; an optical circuit substrate which is formed by an optical waveguide layer having a core portion and cladding portions; and an electrical circuit substrate on which is provided a mounting portion that is used for mounting the optical element, wherein the optical element is mounted on the electrical circuit substrate via the optical circuit substrate and wherein the optical circuit substrate has an optical element mounted thereon and is provided with a receptor structure having a conductive portion that conducts electricity between an electrode of the optical element and an electrode of the electrical circuit substrate.

Abstract: In purifying a gas containing at least one of hydrogen cyanide and hydrogen sulfide as a harmful component by fixing the harmful component in water as an aqueous solution of nitrogen-containing sulfur compound so as to render the gas free of the harmful component, an improvement characterized by:1. burning the aqueous solution of nitrogen-containing sulfur compound to obtain an exhaust gas containing sulfur dioxide,2. separating the sulfur dioxide from the exhaust gas for recovery, and3. exhausting the gas after the separation of the sulfur dioxide.