Abstract: A polymer powder includes a polyamide, wherein a melting point determined in differential scanning calorimetry is 190° C. or higher, a difference between the melting point and a melting onset temperature, which is defined in differential scanning calorimetry as a lowest temperature among temperatures at each of which a first temperature differential value of Heat Flow (W/g) observed between a peak top temperature of an endothermic peak, observed when 10 mg of powder is heated at a rate of 20° C./min from 30° C. in a nitrogen atmosphere, and a temperature point of ?50° C. from the peak top, becomes ?0.2 (W/g.° C.), is less than 30° C., and a D50 particle size is 1 ?m or more and 100 ?m or less.

Abstract: A method of manufacturing a 3-dimensional model object by a powder bed fusion method using a resin granular material, in which the resin granular material comprises a resin powder (A) and a flow aid (B), a sphericity of the resin powder (A) is 80 or more and 100 or less, the resin powder (A) has a D80 particle size of 60 ?m or less and a D20 particle size of 1 ?m or more, the flow aid (B) is contained at an amount of more than 0.01 part by mass and less than 5 parts by mass with respect to 100 parts by mass of the resin powder (A), and steps (a) to (c) are performed in this order repeatedly.

Abstract: A polymer powder includes a polyamide, wherein a melting point determined in differential scanning calorimetry is 190° C. or higher, a difference between the melting point and a melting onset temperature, which is defined in differential scanning calorimetry as a lowest temperature among temperatures at each of which a first temperature differential value of Heat Flow (W/g) observed between a peak top temperature of an endothermic peak, observed when 10 mg of powder is heated at a rate of 20° C./min from 30° C. in a nitrogen atmosphere, and a temperature point of ?50° C. from the peak top, becomes ?0.2 (W/g.° C.), is less than 30° C., and a D50 particle size is 1 ?m or more and 100 ?m or less.

Abstract: A piezoelectric device includes a container and an AT-cut crystal element. The AT-cut crystal element has at least one side surface intersecting with a Z?-axis of the crystallographic axis of the crystal constituted of three surfaces. The first surface is a surface equivalent to a surface formed by rotating the principal surface by 4°±3.5° with an X-axis of the crystal as a rotation axis. The second surface is a surface equivalent to a surface formed by rotating the principal surface by ?57°±5° with the X-axis. The third surface is a surface equivalent to a surface formed by rotating the principal surface by ?42°±5° with the X-axis. When two corner portions on a side of a second side opposed to the first side of the AT-cut crystal element are viewed in plan view, each of the two corner portions have an approximately right angle.

Abstract: A piezoelectric device includes a piezoelectric vibrating piece and a container. The piezoelectric vibrating piece has a rectangular planar shape and has a portion of a first side secured to the container. The piezoelectric vibrating piece has a second side opposing the first side and includes a projecting portion that projects outward from the second side in at least one of proximity of both ends of the second side along the second side.

Abstract: A reflector includes a low refractive index layer and a high refractive index layer. The low refractive index layer has a first average refractive index and has a laminated structure in which an AlN layer and a GaN layer are alternately laminated. The high refractive index layer has a second average refractive index higher than the first average refractive index and includes an InGaN layer.

Abstract: A piezoelectric device includes a container and an AT-cut crystal element. The AT-cut crystal element has at least one side surface intersecting with a Z?-axis of the crystallographic axis of the crystal constituted of three surfaces. The first surface is a surface equivalent to a surface formed by rotating the principal surface by 4°±3.5° with an X-axis of the crystal as a rotation axis. The second surface is a surface equivalent to a surface formed by rotating the principal surface by ?57°±5° with the X-axis. The third surface is a surface equivalent to a surface formed by rotating the principal surface by ?42°±5° with the X-axis. When two corner portions on a side of a second side opposed to the first side of the AT-cut crystal element are viewed in plan view, each of the two corner portions have an approximately right angle.

Abstract: A crystal unit includes an AT-cut crystal element that has a planar shape in a rectangular shape and a part as a thick portion. The crystal element includes a first end portion, a depressed portion, the thick portion, and a second end portion in this order from a side of one short side in viewing a cross section taken along a longitudinal direction near a center of the short side. The depressed portion is a depressed portion disposed from the thick portion toward the first end portion side, depressed with a predetermined angle ?a and subsequently bulged, and connected to the first end portion.

Abstract: A crystal unit includes an AT-cut crystal element that has a planar shape in a rectangular shape and a part as a thick portion. The crystal element includes a first end portion, a first depressed portion, the thick portion, a second depressed portion, and a second end portion in an order from a side of one short side in viewing a cross section taken along a longitudinal direction near a center of the short side. The first depressed portion is a depressed portion disposed from the thick portion toward the first end portion side, depressed with a predetermined angle ?a and subsequently bulged, and connected to the first end portion. The second depressed portion is a depressed portion disposed from the thick portion toward the second end portion side, depressed with a predetermined angle ?b and subsequently bulged, and connected to the second end portion.

Abstract: A crystal unit includes an AT-cut crystal element that has a planar shape in a rectangular shape and a part as a thick portion. The crystal element includes a first end portion, a first depressed portion, the thick portion, a second depressed portion, and a second end portion in this order from a side of one short side, in viewing a cross section taken along a longitudinal direction near a center of the short side. The first depressed portion is a depressed portion disposed from the thick portion toward the first end portion side, depressed with a predetermined angle ?a and subsequently bulged, and connected to the first end portion. The second depressed portion is a depressed portion disposed from the thick portion toward the second end portion side, depressed with a predetermined angle ?b and subsequently bulged, and connected to the second end portion.

Abstract: An AT-cut crystal element is provided. The AT-cut crystal element includes side surfaces intersecting with a Z?-axis of a crystallographic axis of a crystal. At least one side surface of the side surfaces is constituted of three surfaces of a first surface to a third surface. Besides, a crystal resonator including the AT-cut crystal element, and a crystal unit including the crystal resonator are provided.

Abstract: A piezoelectric device includes a piezoelectric vibrating piece, an excitation electrode, an extraction electrode, a container, a pad, a conductive member, and a heat conductive metal film. The excitation electrode is disposed on a front surface and a back surface of the piezoelectric vibrating piece. The extraction electrode is extracted from the excitation electrode. The container houses the piezoelectric vibrating piece. The pad is disposed in the container, and the pad is connected to the piezoelectric vibrating piece. The conductive member connects the pad to the extraction electrode. The heat conductive metal film is disposed at least on a surface of a pad side of the piezoelectric vibrating piece, the heat conductive metal film is extracted from the extraction electrode without contacting the excitation electrode.

Abstract: A crystal unit includes an AT-cut crystal element that has a planar shape in a rectangular shape and a part as a thick portion. The crystal element includes a first end portion, a depressed portion, the thick portion, and a second end portion in this order from a side of one short side in viewing a cross section taken along a longitudinal direction near a center of the short side. The depressed portion is a depressed portion disposed from the thick portion toward the first end portion side, depressed with a predetermined angle ?a and subsequently bulged, and connected to the first end portion.

Abstract: A crystal unit includes an AT-cut crystal element that has a planar shape in a rectangular shape and a part as a thick portion. The crystal element includes a first end portion, a first depressed portion, the thick portion, a second depressed portion, and a second end portion in this order from a side of one short side, in viewing a cross section taken along a longitudinal direction near a center of the short side. The first depressed portion is a depressed portion disposed from the thick portion toward the first end portion side, depressed with a predetermined angle ?a and subsequently bulged, and connected to the first end portion. The second depressed portion is a depressed portion disposed from the thick portion toward the second end portion side, depressed with a predetermined angle ?b and subsequently bulged, and connected to the second end portion.

Abstract: A reflector includes a low refractive index layer and a high refractive index layer. The low refractive index layer has a first average refractive index and has a laminated structure in which an AlN layer and a GaN layer are alternately laminated. The high refractive index layer has a second average refractive index higher than the first average refractive index and includes an InGaN layer.

Abstract: A crystal unit includes an AT-cut crystal element and a container. The AT-cut crystal element has an approximately rectangular planar shape. The AT-cut crystal element includes a first inclined portion, second inclined portions, and a first secured portion. The first inclined portion is inclined such that the crystal element decreases in thickness from a proximity of the first side to the first side. The second inclined portions are disposed on respective both ends of the first side, the second inclined portions being formed integrally with the first inclined portion. The second inclined portions are inclined gentler than the first inclined portion. The first secured portion and a second secured portion are formed integrally with the second inclined portion. The first secured portion and the second secured portion each project out from the first side to outside the crystal element to be used for securing with the securing members.

Abstract: A crystal unit includes an AT-cut crystal element, excitation electrodes, extraction electrodes. The AT-cut crystal element has an approximately rectangular planar shape. The excitation electrodes are disposed on front and back of principal surfaces of the AT-cut crystal element. The extraction electrodes are extended from the excitation electrodes to a side of one side of the AT-cut crystal element via a side surface of the AT-cut crystal element. Assuming that an extraction angle of the extraction electrode from the principal surface to the side surface is defined as an angle ? with respect to an X-axis of a crystallographic axis of a crystal, the angle ? is equal to or greater than 59 degrees and equal to or less than 87 degrees.

Abstract: An AT-cut crystal element includes a crystal element having two side surfaces (namely, a Z?-surface) intersecting with a Z-axis of a crystallographic axis thereof. At least one of the two side surfaces is constituted of three of first to third surfaces. The first to the third surfaces meeting following conditions: the first to the third surfaces intersect with one another in this order and formed by rotating a principal surface of the crystal element by predetermined angles; and expressing the angle of the first surface as ?1, a length of the first surface as D, a thickness of a part of the crystal element having the principal surface as t, and M=D/t, and a conversion percentage as fn (M, (?1)), the ?1 and the M are set such that the conversion percentage fn (M, (?1)) becomes a predetermined value Th or less.

Abstract: A piezoelectric device includes a piezoelectric vibrating piece and a container. The piezoelectric vibrating piece has a rectangular planar shape and has a portion of a first side secured to the container. The piezoelectric vibrating piece has a second side opposing the first side and includes a projecting portion that projects outward from the second side in at least one of proximity of both ends of the second side along the second side.

Abstract: A crystal unit includes an AT-cut crystal element that has a planar shape in a rectangular shape and a part as a thick portion. The crystal element includes a first end portion, a first depressed portion, the thick portion, a second depressed portion, and a second end portion in an order from a side of one short side in viewing a cross section taken along a longitudinal direction near a center of the short side. The first depressed portion is a depressed portion disposed from the thick portion toward the first end portion side, depressed with a predetermined angle ?a and subsequently bulged, and connected to the first end portion. The second depressed portion is a depressed portion disposed from the thick portion toward the second end portion side, depressed with a predetermined angle ?b and subsequently bulged, and connected to the second end portion.