Abstract: A laser beam applying unit in a laser processing apparatus includes a laser oscillator for emitting a laser beam, a beam condenser for focusing the laser beam emitted from the laser oscillator and applying the focused laser beam to a workpiece held on a holding table, and a scanning unit that is disposed on an optical path of the laser beam between the laser oscillator and the beam condenser and that has scanning mirrors for scanning the laser beam and guiding the scanned laser beam toward the beam condenser. The scanning mirrors are housed in a chamber having a first window for allowing the laser beam emitted from the laser oscillator to pass therethrough to the scanning mirrors and a second window for allowing the laser beam scanned by the scanning mirrors to pass therethrough to the beam condenser.

Abstract: A laser beam irradiation unit of a laser processing apparatus includes a first splitting unit that causes a laser beam emitted from a laser oscillator to branch into a first optical path and a second optical path, a first beam condenser that focuses the laser beam having been introduced to the first optical path, and a second beam condenser that focuses the laser beam having been introduced to the second optical path. The laser beam irradiation unit further includes a second splitting unit on the first optical path between the first splitting unit and the first beam condenser that splits the laser beam into at least two laser beams, and a laser beam scanning unit on the second optical path between the first splitting unit and the second beam condenser that executes scanning with the laser beam and introduces the laser beam to the second beam condenser.

Abstract: A gas sensor element (3) includes: a solid electrolyte body (3s) having a bottomed tubular shape and a closed front end, and extending in the direction of an axial line O; an inside electrode (50) which is provided on an inner surface of the solid electrolyte body; an outside electrode (51) which is provided on an outer surface of the solid electrolyte body; and a porous protective layer (80) which covers the outside electrode, the porous protective layer has an inside region (81) which covers the outside electrode and an outside region (82) which covers the inside region and has a lower porosity than the inside region, and the outside region is formed of a sintered body of ceramic and glass.

Abstract: A gas sensor element (3) includes: a solid electrolyte body (3s) having a bottomed tubular shape and a closed front end, and extending in the direction of an axial line O; an inside electrode (50) which is provided on an inner surface of the solid electrolyte body; an outside electrode (51) which is provided on an outer surface of the solid electrolyte body; and a porous protective layer (80) which covers the outside electrode, the porous protective layer has an inside region (81) which covers the outside electrode and an outside region (82) which covers the inside region and has a lower porosity than the inside region, and the outside region is formed of a sintered body of ceramic and glass.

Abstract: A gas sensor comprising: a gas detecting element extending in an axial direction and including a detecting electrode provided on an outer surface of a leading end side of the gas detecting element, and a lead portion connecting to the detecting electrode and extending toward a rear end side of the gas detecting element; a cylindrical metal shell housing the gas detecting element such that the gas detecting element protrudes from a leading end side of the metal shell; a powder layer filling a gap between the gas detecting element and the metal shell and covering at least a portion of the lead portion; and an insulating layer provided between the powder layer and the lead portion. Also disclosed is a method for manufacturing the gas sensor which includes forming the insulating layer by at least: applying a glass paste; drying the glass paste; and heat-treating the glass paste.

Abstract: To provide a gas sensor element having a base body whose durability is unlikely to deteriorate during the use and exhibiting excellent endurance and responsiveness. [Means for Solution] A gas sensor element 2 comprising: a closed-bottomed cylindrical base body 28 made of solid electrolyte which contains zirconia as a principal component; an outer electrode 26 formed on an outer surface of the base body 28; an inner electrode 27 formed on an inner surface of the base body 28; and an adhesive layer 29 formed between the base body 28 and the outer electrode 26 and containing zirconia as a principal component, wherein a proportion of tetragonal in zirconia particles of the base body 28 falls within the range from 45% or more to 60% or less and, wherein a proportion of tetragonal in zirconia particles of the adhesive layer 29 is greater than that of tetragonal in zirconia particles of the base body 28.

Abstract: To provide a gas sensor element having a base body whose durability is unlikely to deteriorate during the use and exhibiting excellent endurance and responsiveness. [Means for Solution] A gas sensor element 2 comprising: a closed-bottomed cylindrical base body 28 made of solid electrolyte which contains zirconia as a principal component; an outer electrode 26 formed on an outer surface of the base body 28; an inner electrode 27 formed on an inner surface of the base body 28; and an adhesive layer formed between the base body 28 and the outer electrode and containing zirconia as a principal component, wherein a proportion of tetragonal in zirconia particles of the base body 28 falls within the range from 45% or more to 60% or less and, wherein a proportion of tetragonal in zirconia particles of the adhesive layer 29 is greater than that of tetragonal in zirconia particles of the base body 28.

Abstract: The oxygen sensor of the present invention has excellent durability capable of effectively preventing contamination with lead or the like for a detection electrode even in low temperature exhaust gases, and having stable response over a long period of time. The contamination preventive layer provided in the sensor device comprises composite powders having coarse powders covered therearound with fine powders, and hollows not filled with fine powders are scattered in gaps among the composite powders. Both the coarse and fine powders comprise ceramic powders. Further, it is particularly preferred that the ceramic powders are powders of a titania powder having a peak at 1 ?m or less and a composite ceramic powder containing alumina such as spinel having a peak at 10 ?m or more.

Abstract: A gas sensor comprising: a gas detecting element extending in an axial direction and including a detecting electrode provided on an outer surface of a leading end side of the gas detecting element, and a lead portion connecting to the detecting electrode and extending toward a rear end side of the gas detecting element; a cylindrical metal shell housing the gas detecting element such that the gas detecting element protrudes from a leading end side of the metal shell; a powder layer filling a gap between the gas detecting element and the metal shell and covering at least a portion of the lead portion; and an insulating layer provided between the powder layer and the lead portion. Also disclosed is a method for manufacturing the gas sensor which includes forming the insulating layer by at least: applying a glass paste; drying the glass paste; and heat-treating the glass paste.

Abstract: The oxygen sensor of the present invention has excellent durability capable of effectively preventing contamination with lead or the like for a detection electrode even in low temperature exhaust gases, and having stable response over a long period of time. The contamination preventive layer provided in the sensor device comprises composite powders having coarse powders covered therearound with fine powders, and hollows not filled with fine powders are scattered in gaps among the composite powders. Both the coarse and fine powders comprise ceramic powders. Further, it is particularly preferred that the ceramic powders are powders of a titania powder having a peak at 1 &mgr;m or less and a composite ceramic powder containing alumina such as spinel having a peak at 10 &mgr;m or more.

Abstract: The oxygen sensor of the present invention has excellent durability capable of effectively preventing contamination with lead or the like for a detection electrode even in low temperature exhaust gases, and having stable response over a long period of time. The contamination preventive layer provided in the sensor device comprises composite powders having coarse powders covered therearound with fine powders, and hollows not filled with fine powders are scattered in gaps among the composite powders. Both the coarse and fine powders comprise ceramic powders. Further, it is particularly preferred that the ceramic powders are powders of a titania powder having a peak at 1 &mgr;m or less and a composite ceramic powder containing alumina such as spinel having a peak at 10 &mgr;m or more.

Abstract: A gas sensor element includes a solid electrolyte layer having a plurality of projections formed on its outer surface, an inner electrode formed on the inner surface of the solid electrolyte layer, an outer electrode formed on the outer surface of the solid electrolyte layer, an outer electrode formed on the outer surface of the solid electrolyte layer and a spinel protection layer formed on the outer electrode for protection. The projections are formed on the outer surface of the solid electrolyte layer such that they are formed in a single layer; an area occupied by the projections accounts for 10% to 85% of the outer surface of the solid electrolyte layer and the distance between the neighboring projections is 5 &mgr;m to 300 &mgr;m. Thus, the outer electrode is formed on the solid electrolyte layer in such a manner as to penetrate into pits formed between neighboring projections and is thus strongly bonded to the solid electrolyte layer, thereby improving thermal durability.