Abstract: A controller of a thrust generating device executes one of first control of controlling thrust by changing the pitch angle of each blade while maintaining the rotational speed of a propeller at a reference value, or second control of allowing the thrust greater than the thrust generated in the first control to be generated by making the rotational speed of the propeller larger than the reference value.

Abstract: A manufacturing apparatus for a group-III nitride crystal, the manufacturing apparatus includes: a raw material chamber that produces therein a group-III element oxide gas; and a nurturing chamber in which a group-III element oxide gas supplied from the raw material chamber and a nitrogen element-containing gas react therein to produce a group-III nitride crystal on a seed substrate, wherein an angle that is formed by a direction along a shortest distance between a forward end of a group-III element oxide gas supply inlet to supply the group-III element oxide gas into the nurturing chamber and an outer circumference of the seed substrate placed in the nurturing chamber, and a surface of the seed substrate is denoted by “?”, wherein a diameter of the group-Ill element oxide gas supply inlet is denoted by “S”, wherein a distance between a surface, on which the seed substrate is placed, of a substrate susceptor that holds the seed substrate and a forward end of a first carrier gas supply inlet to supply a first

Abstract: A manufacturing method for a group-III nitride crystal, the manufacturing method includes: preparing a seed substrate; increasing temperature of the seed substrate placed in a nurturing chamber; and supplying a group-III element oxide gas produced in a raw material chamber connected to the nurturing chamber by a connecting pipe and a nitrogen element-containing gas into the nurturing chamber to grow a group-III nitride crystal on the seed substrate, wherein a flow amount y of a carrier gas supplied into the raw material chamber at the temperature increase step satisfies following two relational equations (I) and (II), y<[1?k*H(Ts)]/[k*H(Ts)?j*H(Tg)]*j*H(Tg)*t (I), y?1.58*10?4*(22.

Abstract: An improved lens unit can be used in an in-vehicle camera or the like, in a condition where a forefront lens is exposed to the outside for a long time. Here, the resin lens within the lens unit has an improved durability at a high temperature. The lens unit has a plurality of lenses arranged side by side with the optical axes thereof aligned with each other. The lenses include glass lens and resin lens. The lens closest to the object is a glass lens which is closest to the object side and is coated with an ultra-hard film. Resin lenses each have a high temperature resistant reflection preventing film. The lens is a combined lens in which a lens and a lens are bonded together, and is then covered with a high temperature resistant reflection preventing film after bonding.

Abstract: A method of manufacturing a group III nitride crystal according to a first aspect includes: preparing a seed substrate; generating a group III element oxide gas; supplying the group III element oxide gas; supplying a nitrogen element-containing gas; supplying an oxidizing gas containing nitrogen element containing at least one selected from the group consisting of NO gas, NO2 gas, N2O gas, and N2O4 gas; and growing the group III nitride crystal on the seed substrate.

Abstract: A group-III nitride substrate includes: a first region having a first impurity concentration in a polished surface; and a second region having a second impurity concentration lower than the first impurity concentration in the polished surface, wherein a first dislocation density of the first region is lower than a second dislocation density of the second region.

Abstract: An improved lens unit can be used in an in-vehicle camera or the like, in a condition where a forefront lens is exposed to the outside for a long time. Here, the resin lens within the lens unit has an improved durability at a high temperature. The lens unit has a plurality of lenses arranged side by side with the optical axes thereof aligned with each other. The lenses include glass lens and resin lens. The lens closest to the object is a glass lens which is closest to the object side and is coated with an ultra-hard film. Resin lenses each have a high temperature resistant reflection preventing film. The lens is a combined lens in which a lens and a lens are bonded together, and is then covered with a high temperature resistant reflection preventing film after bonding.

Abstract: A method of manufacturing a group-III nitride crystal includes: preparing a seed substrate; and supplying a group-III element oxide gas and a nitrogen element-containing gas at a supersaturation ratio (Po/Pe) greater than 1 and equal to or less than 5, then, growing a group-III nitride crystal on the seed substrate, wherein the Po is a supply partial pressure of the group-III element oxide gas, and the Pe is an equilibrium partial pressure of the group-III element oxide gas.

Abstract: A group-III nitride substrate includes: a first region having a first impurity concentration in a polished surface; and a second region having a second impurity concentration lower than the first impurity concentration in the polished surface, wherein a first dislocation density of the first region is lower than a second dislocation density of the second region.

Abstract: A group III nitride crystal, wherein the group III nitride crystal is doped with an N-type dopant and a hydrogen element, and the concentration of the N-type dopant is 1×1020 cm?3 or more, and the concentration of the hydrogen element is 1×1019 cm?3 or more.

Abstract: A group III nitride crystal, wherein the group III nitride crystal is doped with an N-type dopant and a germanium element, the concentration of the N-type dopant is 1×1019 cm?3 or more, and the concentration of the germanium element is nine times or more higher than the concentration of the N-type dopant.

Abstract: Provided is a polycrystalline ceramic substrate to be bonded to a compound semiconductor substrate with a bonding layer interposed therebetween, wherein at least one of relational expression (1) 0.7<?1/?2<0.9 and relational expression (2) 0.7<?3/?4<0.9 holds, where ?1 represents a linear expansion coefficient of the polycrystalline ceramic substrate at 30° C. to 300° C. and ?2 represents a linear expansion coefficient of the compound semiconductor substrate at 30° C. to 300° C., and ?3 represents a linear expansion coefficient of the polycrystalline ceramic substrate at 30° C. to 1000° C. and ?4 represents a linear expansion coefficient of the compound semiconductor substrate at 30° C. to 1000° C.

Abstract: A manufacturing method for a group-III nitride crystal, the manufacturing method includes: preparing a seed substrate; increasing temperature of the seed substrate placed in a nurturing chamber; and supplying a group-III element oxide gas produced in a raw material chamber connected to the nurturing chamber by a connecting pipe and a nitrogen element-containing gas into the nurturing chamber to grow a group-III nitride crystal on the seed substrate, wherein a flow amount y of a carrier gas supplied into the raw material chamber at the temperature increase step satisfies following two relational equations (I) and (II), y<[1?k*H(Ts)]/[k*H(Ts)?j*H(Tg)]j*H(Tg)*t (I), y?1.58*10?4*(22.

Abstract: A manufacturing apparatus for a group-III nitride crystal, the manufacturing apparatus includes: a raw material chamber that produces therein a group-III element oxide gas; and a nurturing chamber in which a group-III element oxide gas supplied from the raw material chamber and a nitrogen element-containing gas react therein to produce a group-III nitride crystal on a seed substrate, wherein an angle that is formed by a direction along a shortest distance between a forward end of a group-III element oxide gas supply inlet to supply the group-III element oxide gas into the nurturing chamber and an outer circumference of the seed substrate placed in the nurturing chamber, and a surface of the seed substrate is denoted by “?”, wherein a diameter of the group-Ill element oxide gas supply inlet is denoted by “S”, wherein a distance between a surface, on which the seed substrate is placed, of a substrate susceptor that holds the seed substrate and a forward end of a first carrier gas supply inlet to supply a first

Abstract: A group Ill nitride crystal manufacturing apparatus includes a raw material chamber generating a group Ill elemental oxide gas, and a growth chamber allowing the group Ill element oxide gas supplied from the raw material chamber to react with a nitrogen element-containing gas to generate a group III nitride crystal on a seed substrate, and the growth chamber incudes a decomposition promoting part promoting decomposition of the unreacted nitrogen element- containing gas between the seed substrate and an exhaust port for discharging the unreacted group Ill oxide gas and the nitrogen element-containing gas.

Abstract: A method of manufacturing a group III nitride crystal includes: preparing a seed substrate; causing surface roughness on the surface of the seed substrate; and supplying a group III element oxide gas and a nitrogen element-containing gas to grow a group III nitride crystal on the seed substrate.

Abstract: A group-III nitride substrate includes: a base material part of a group-III nitride including a front surface, a back surface, and an inner layer between the front surface and the back surface, wherein the carbon concentration of the front surface of the base material part is higher than the carbon concentration of the inner layer.

Abstract: An object of the present invention is to provide a method for producing a group III nitride crystal in which generation of breaking or cracks is less likely to occur. To achieve the object, the method for producing a group III nitride crystal includes: seed crystal preparation including disposing a plurality of crystals of a group III nitride as a plurality of seed crystals on a substrate; and crystal growth including growing group III nitride crystals by contacting a surface of each of the seed crystals with a melt containing at least one group III element selected from gallium, aluminum, and indium and an alkali metal in an atmosphere containing nitrogen. In the seed crystal preparation, the plurality of seed crystals are disposed within a hexagonal region provided on the substrate.

Abstract: A method of manufacturing a group-III nitride crystal includes: preparing a seed substrate; and supplying a group-III element oxide gas and a nitrogen element-containing gas at a supersaturation ratio (Po/Pe) greater than 1 and equal to or less than 5, then, growing a group-III nitride crystal on the seed substrate, wherein the Po is a supply partial pressure of the group-III element oxide gas, and the Pe is an equilibrium partial pressure of the group-III element oxide gas.

Abstract: A method of manufacturing a group-III nitride crystal includes: a seed crystal preparation step of preparing a plurality of dot-shaped group-III nitrides on a substrate as a plurality of seed crystals for growth of a group-III nitride crystal; and a crystal growth step of bringing surfaces of the seed crystals into contact with a melt containing an alkali metal and at least one group-III element selected from gallium, aluminum, and indium in an atmosphere containing nitrogen and thereby reacting the group-III element with the nitrogen in the melt to grow the group-III nitride crystal.