Abstract: An optical apparatus includes a light emitting apparatus and a host apparatus. The light emitting apparatus includes a housing extending in a first direction, a light emitting device mounted in the housing, an optical connector including a first optical connection part provided at one end of the housing, and an electrical connector including a first electrical connection part provided at one end of the housing and receiving a voltage to drive the light emitting device. The host apparatus includes a host optical connector including a second optical connection part which faces the first optical connection part and is optically coupled thereto, a host electrical connector including a second electrical connection part facing the first electrical connection part and being electrically connected to the first electrical connection part, and a host board mounting the host optical connector and the host electrical connector thereon.

Abstract: A multilayered air-fuel ratio sensor consists of a plurality of substrate layers. At least one heterogeneous boundary layer is interposed between the plurality of substrate layers. The heterogeneous boundary layer has a thickness in a range of 10 to 100 ?m. The heterogeneous boundary layer absorbs thermal shocks or any other stresses acting on the substrate layers and stops the growth of cracks.

Abstract: An exhaust gas purifying filter is made of a ceramic material in a honeycomb structure having introduction passages for introducing exhaust gas that includes particulate matter emitted from an internal combustion engine, porous walls that collect the particulate matter and exhaust passages for exhausting the exhaust gas after the particulate matter has been removed therefrom, with the porous walls supporting a catalyst for oxidizing and removing the particulate matter. The porosity of the porous wall is in a range from 55 to 80%, the mean pore size is in-a range from 30 to 50 ?m, and the total volume X of the pores included in the exhaust gas purifying filter and the volume Y of the pores that are not smaller than 100 ?m satisfy the relation of inequality Y/X?0.05.

Abstract: A ceramic body that can support a required amount of catalyst component, without lowering the characteristics such as strength, manufactured without forming a coating layer and providing a high performance ceramic catalyst body that is excellent in practical utility and durability. This ceramic body is made by substituting at least one of the constituent elements of cordierite that constitutes the substrate ceramic, for example Al, with W that is the element having an empty orbit in d or f orbit, has high bonding strength and is less susceptible to deterioration since the catalyst component Pt is supported by means of chemical bonding.

Abstract: An exhaust gas purifying filter is made of a ceramic material in a honeycomb structure having introduction passages for introducing exhaust gas that includes particulate matter emitted from an internal combustion engine, porous walls that collect the particulate matter and exhaust passages for exhausting the exhaust gas after the particulate matter has been removed therefrom, with the porous walls supporting a catalyst for oxidizing and removing the particulate matter. The porosity of the porous wall is in a range from 55 to 80%, the mean pore size is in-a range from 30 to 50 ?m, and the total volume X of the pores included in the exhaust gas purifying filter and the volume Y of the pores that are not smaller than 100 ?m satisfy the relation of inequality Y/X?0.05.

Abstract: A catalyst-loaded ceramic filter made of a ceramic material capable of directly supporting a catalyst component thereon is capable of providing early activation of the catalyst with a low coefficient of thermal expansion and light weight, without compromising the high porosity of the filter substrate. A catalyst-loaded ceramic filter is made of a ceramic material of which one or more kinds of element among its constituent elements is substituted with an element other than the constituent elements, for example a ceramic material with a part of Si or other elements included in cordierite is substituted with W or Co, as a filter substrate of honeycomb structure having a number of cells separated by porous walls, and supporting a catalyst such as a noble metal directly on the W.

Abstract: A gas sensor element which may be employed in measuring the concentration of gas such O2, NOx, or CO. The gas sensor element consists of an electrochemical cell made up of a solid electrolyte body formed by a partially stabilized zirconia and a pair of electrodes disposed on the solid electrolyte body. The electrochemical cell is subjected to an aging treatment in which the dc current is applied to the electrodes at a given voltage to enhance the activation of the electrochemical cell.

Abstract: The oxygen concentration detector of the present invention includes a sensor element having a solid electrolyte and having an external electrode and an internal electrode provided on the external surface and the internal surface, respectively, and a heater provided adjacent to the internal surface of the sensor element, in which a high-emissivity layer consisting of a material having a high emissivity is provided on the internal surface of the sensor element and/or the surface of the heater.

Abstract: A gas sensor element which may be employed in measuring the concentration of gas such O2, NOx, or CO. The gas sensor element consists of an electrochemical cell made up of a solid electrolyte body formed by a partially stabilized zirconia and a pair of electrodes disposed on the solid electrolyte body. The electrochemical cell is subjected to an aging treatment in which the dc current is applied to the electrodes at a given voltage to enhance the activation of the electrochemical cell.

Abstract: The invention provides a gas concentration detection element that can prevent the drop of catalytic activity due to thermal aggregation of catalyst particles under high temperature conditions, can maintain a stable output for a long time and can be easily produced at a low production cost. A reference electrode 12 is formed on an inner surface of a cup-like oxygen ion conductive solid electrolyte 11 and a detection electrode 13 is formed on its outer surface to constitute a gas concentration detection element 1 for detecting a specific gas component in a measured gas. A catalyst layer 15 is constituted by directly supporting a catalyst component on ceramic support particles, such as particles of element-substituted cordierite, through a chemical bond so that both bonding strength and durability can be improved.

Abstract: The present invention has an object to obtain a ceramic body that can support a required amount of catalyst component, without lowering the characteristics such as strength, being manufactured without forming a coating layer and providing a high performance ceramic catalyst body that is excellent in practical utility and durability.

Abstract: An exhaust gas purifying filter that does not break and melt and has high capacity to remove particulate matter, and a method of manufacturing the same, are provided.

Abstract: The present invention provides a catalyst-loaded ceramic filter that is made of a ceramic material capable of directly supporting a catalyst component thereon, and is capable of providing early activation of the catalyst with a low coefficient of thermal expansion and light weight, without compromising the high porosity of the filter substrate.

Abstract: A sensor element has a solid electrolyte body holding a reference gas side electrode and a measurement gas side electrode on surfaces thereof. The measurement gas side electrode is covered with a porous protective layer including a component as a lead getter, which reacts with lead contained in measurement gas. Accordingly, lead is removed from measurement gas by the protective layer not to be attached to the measurement gas side electrode. As a result, the sensor element can be used in measurement gas containing lead, without deteriorating responsibility and output thereof.

Abstract: A composite gas sensor comprises a pump cell, a NOx sensor cell and an oxygen sensor cell. The NOx sensor cell is connected to a first ammeter and a constant power source to measure the NOx concentration of a sample gas. The pump cell is connected to a second ammeter and a variable power source to measure an air-fuel ratio of the sample gas. The oxygen sensor cell is connected to a voltmeter. A controller adjusts the variable power source to produce a constant value from the voltmeter.

Abstract: A solid electrolytic body has an inside space serving as a reference gas chamber. A sensing electrode and a reference electrode are formed on the surface of the solid electrolytic body. A heater is disposed in the reference gas chamber. A contact portion comprises a region where the heater is brought into contact with the inner surface of the solid electrolytic body and an opposing region on the outer surface of the solid electrolytic body. The sensing electrode includes at least part of the contact portion. A gas receiving surface region, exposed to the measuring gas, extends from an element tip to a position spaced by a distance L away from the element tip. At least part of the contact portion is located in a region extending from the element tip to a position spaced by a distance 0.4L away from the element tip. The sensing electrode is entirely located in a region extending from the element tip to a position spaced by a distance 0.8L away from the element tip.

Abstract: An improved structure of an oxygen sensing element installed in an oxygen sensor designed to measure an oxygen content in gases is provided. The structure includes a cup-shaped solid electrolyte body, an inner electrode, and an outer electrode. The solid electrolyte body has a portion exposed to the gases which has a given length. The inner electrode is formed on an inner wall of the solid electrolyte body and exposed to air. The outer electrode is formed on an outer wall of the solid electrolyte body and exposed to the gases through a protective layer. The oxygen content in the gases is measured based on output signals from the inner and outer electrodes. The outer electrode occupies an area on the outer wall of the solid electrolyte body within a range of 80% of the given length of the gas-exposed portion of the solid electrolyte body and has a thickness ranging from 1.2 to 3.0 &mgr;m.

Abstract: A composite gas sensor comprises a pump cell, a NOx sensor cell and an oxygen sensor cell. The NOx sensor cell is connected to a first ammeter and a constant power source to measure the NOx concentration of a sample gas. The pump cell is connected to a second ammeter and a variable power source to measure an air-fuel ratio of the sample gas. The oxygen sensor cell is connected to a voltmeter. A controller adjusts the variable power source to produce a constant value from the voltmeter.

Abstract: A multilayered air-fuel ratio sensor consists of a plurality of substrate layers. At least one heterogeneous boundary layer is interposed between the plurality of substrate layers. The heterogeneous boundary layer has a thickness in a range of 10 to 100 &mgr;m. The heterogeneous boundary layer absorbs thermal shocks or any other stresses acting on the substrate layers and stops the growth of cracks.

Abstract: A multilayered air-fuel ratio sensing element has a zirconic solid electrolytic body and a heat-generating portion including an alumina substrate located adjacent to the zirconic solid electrolytic body. The zirconic solid electrolytic body is made of a partially stabilized zirconia containing 5˜7 mol % yttria and having a mixed phase structure including a cubic phase, a monoclinic phase and a tetragonal phase. The zirconic solid electrolytic body has a relative density of 94˜100% with a mean sintered grain size RZR of 0.5˜3.0 &mgr;m. The alumina substrate has a relative density of 95˜100% with a mean sintered grain size RAL of 0.5˜4.0 &mgr;m. And, the partially stabilized zirconia has an M/C ratio in a range from 0.05 to 0.25.