Abstract: An optical system includes, in order from a pupil surface side to a display surface side, a first reflective polarizing plate, a first lens having a positive refractive power, a half mirror, a second lens having a positive refractive power, and a second reflective polarizing plate. The optical system further includes a first quarter wave plate arranged between a pupil surface and the half mirror, and a second quarter wave plate arranged between the half mirror and a display surface. The second lens has a paraxially convex surface on the pupil surface side. Further, in the case where a paraxial curvature radius of a surface of the first lens on the pupil surface side is r1 and a paraxial curvature radius of a surface of the first lens on the display surface side is r2, the optical system satisfies a conditional expression below: ?3.2<r1/r2<?0.9.

Abstract: A semiconductor module includes a wiring board, a semiconductor element disposed on and electrically connected to a conductor pattern of the wiring board, and a wiring member electrically connecting a conductor to an electrode of the semiconductor element. The wiring member includes a first conductor spacer, a second conductor spacer, and a laminate connecting the conductor spacers to each other. The laminate includes a plurality of conductor foils that are disposed in a laminated manner. The plurality of conductor foils includes at least one intermediate conductor foil, and first and second conductor foils sandwiching the intermediate conductor foil interposed therebetween. The intermediate conductor foil includes a void formation area in which a void is formed in the thickness direction between the linking region of the first conductor foil and the linking region of the second conductor foil.

Abstract: A ring resonator in which a nonlinear effect is prevented from becoming apparent, and a method for manufacturing such a ring resonator are provided. A ring resonator according to the present disclosure includes an input waveguide, an output waveguide, and a ring waveguide including a first waveguide part optically connected to the input waveguide, a second waveguide part optically connected to the output waveguide, two curved waveguide parts each connecting the first and second waveguide parts to each other, and a heater disposed along a third waveguide part, the third waveguide part being a longer one of the two waveguide parts. Lengths of the two waveguide parts are different from each other. A first direction along the first waveguide part and a second direction along the second waveguide part are not parallel to each other.

Abstract: A ring resonator includes an input waveguide, a first ring waveguide, a second ring waveguide, an output waveguide, and a heater. The first ring waveguide includes a first waveguide part optically connected to the input waveguide, and a third waveguide part which is a longer one of two waveguide parts connecting the first waveguide part to a second waveguide part optically connected to the second ring waveguide. The second ring waveguide includes a fourth waveguide part optically connected to the second waveguide part, and a sixth waveguide part which is a longer one of two waveguide parts connecting the fourth waveguide part to a fifth waveguide part optically connected to the output waveguide. The heater extends along the third and six waveguide parts.

Abstract: An optical system includes, in order from the pupil plane side to the display plane side, a first reflective polarizing plate, a first lens having a convex surface on the pupil plane side, a half mirror, a second lens having a convex surface on the display plane side, a second reflective polarizing plate, a first ¼ wavelength plate, and a second ¼ wavelength plate. The optical system satisfies: 1 ? 4 < r ? 1 / T ? 1 < 250 ( 1 ) 0.7 < ( D ? 2 / f ? 2 ) × 1 ? 0 ? 0 < 5. ( 2 ) where r1 is the paraxial radius of curvature of a surface of the first lens on the pupil plane side, T1 is the distance on an optical axis from a surface of the first lens on the display plane side to a surface of the second lens on the pupil plane side, D2 is the thickness of the second lens L2 on the optical axis, and f2 is the focal length of the second lens.

Abstract: A method for producing a compound of a formula (3), including reacting a compound of a formula (1) with a compound of a formula (2) by using a tertiary alcohol and a base: where R1, R2, R3, R4, R5, R6, R7, R8, and R9 are each independently a hydrogen atom, a halogen atom, a (C1-C4)alkyl, or a (C1-C4)alkoxy, the amount of the base used is 2.0-4.0 equivalents per 1 equivalent of the compound of formula (2), the amount of the tertiary alcohol used is 0.3-2.5 equivalents per 1 equivalent of the compound of formula (2), the base is a plurality of compounds comprising a lithium-containing base as a first compound, and a second compound selected from the group consisting of alkali metal hydrides, alkali metal amides, alkoxides, alkyl metals, alkali metals, and organic bases, and the reaction is performed in the presence of an aromatic hydrocarbon solvent.

Abstract: Provided are a wavelength monitoring apparatus, a wavelength monitoring method, and a wavelength locker that are capable of monitoring a wavelength of light by using a simple configuration. A first optical waveguide guides light of a single mode. An excitation structure excites light of a first mode and light of a second mode from the single-mode light propagating through the first optical waveguide. Through a second optical waveguide, the first-mode light and the second-mode light propagate. A first light receiver receives a combined wave of the first-mode light and the second-mode light. A wavelength analysis unit determines a wavelength of the single-mode light associated with light intensity of the combined wave received by the light receiver, based on information being acquired in advance and indicating a correspondence relationship between the light intensity and a wavelength of the combined wave received by the light receiver.

Abstract: An optical system includes, in order from a pupil surface side to a display surface side, a first reflective polarizing plate, a first lens having a positive refractive power, a half mirror, a second lens having a positive refractive power, and a second reflective polarizing plate. The optical system further includes a first quarter wave plate arranged between a pupil surface and the half mirror, and a second quarter wave plate arranged between the half mirror and a display surface. The second lens has a paraxially convex surface on the pupil surface side. Further, in the case where a paraxial curvature radius of a surface of the first lens on the pupil surface side is r1 and a paraxial curvature radius of a surface of the first lens on the display surface side is r2, the optical system satisfies a conditional expression below: (1) ?3.2<r1/r2<?0.9.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_G?? is 6.1 ([GPa?1·?m?2.5/rad8]·10?12) or less when represented by F?BL_G??=F?BL_G×F?BL_??, where F?BL_G is geometry microbend loss characteristic and F?BL_?? is optical microbend loss characteristic.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_G?? is 6.1 ([GPa?1·?m?2.5/rad8]·10?12) or less when represented by F?BL_G??=F?BL_G×F?BL_??, where F?BL_G is geometry microbend loss characteristic and F?BL_?? is optical microbend loss characteristic.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_GO is 2.6 ([GPa?1·?m?10.5·dB/turn]·10?27) or less, when represented by F?BL_GO=F?BL_G×F?BL_O by using geometry microbend loss characteristic F?BL_G and optical microbend loss characteristic F?BL_O.

Abstract: A method for producing a compound of a formula (3), including reacting a compound of a formula (1) with a compound of a formula (2) by using a tertiary alcohol and a base: where R1, R2, R3, R4, R5, R6, R7, R8, and R9 are each independently a hydrogen atom, a halogen atom, a (C1-C4)alkyl, or a (C1-C4)alkoxy, the amount of the base used is 2.0-4.0 equivalents per 1 equivalent of the compound of formula (2), the amount of the tertiary alcohol used is 0.3-2.5 equivalents per 1 equivalent of the compound of formula (2), the base is a plurality of compounds comprising a lithium-containing base as a first compound, and a second compound selected from the group consisting of alkali metal hydrides, alkali metal amides, alkoxides, alkyl metals, alkali metals, and organic bases, and the reaction is performed in the presence of an aromatic hydrocarbon solvent.

Abstract: A method for producing a nitroso compound of the following formula (3), comprising reacting a compound of the following formula (1) with a compound of the following formula (2) by using a tertiary alcohol and a base. wherein R1, R2, R3, R4, R5, R6, R7, R8, and R9 are each independently a hydrogen atom, a halogen atom, a (C1-C4) alkyl, or a (C1-C4) alkoxy.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_GO is 2.6 ([GPa?1·?m?10.5·dB/turn]·10?27) or less, when represented by F?BL_GO=F?BL_G×F?BL_O by using geometry microbend loss characteristic F?BL_G and optical microbend loss characteristic F?BL_O.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_G?? is 6.1 ([GPa?1·?m?2.5/rad8]·10?12) or less when represented by F?BL_G??=F?BL_G×F?BL_??, where F?BL_G is geometry microbend loss characteristic and F?BL_?? is optical microbend loss characteristic.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_GO is 2.6 ([GPa?1·?m?10.5·dB/turn]·10?27) or less, when represented by F?BL_GO=F?BL_G×F?BL_O by using geometry microbend loss characteristic F?BL_G and optical microbend loss characteristic F?BL_O.

Abstract: The present invention aims to provide a fluorescent reagent capable of highly sensitive imaging of a lipid droplet at a level ranging from cultured cells to individuals. A lipid droplet detection reagent including a compound represented by the following General Formula (I) is provided. In the formula, m represents an integer of 0 to 5; n represents an integer of 0 to 5; X is selected from the group consisting of a sulfur atom, an oxygen atom, and a group represented by NR; R is a hydrogen atom or a group represented by —(CH2)yCH3; and y represents an integer of 0 to 5.

Abstract: A lead frame wiring structure including first and second bonding parts positioned apart from each other, and a coupling part extending in a first direction to couple the first and second bonding parts. The coupling part includes a coupling face section, and first and second leg sections extending respectively from two opposite end portions of the coupling face section toward the first and second bonding parts. The first bonding part includes a wide section having a side edge portion and a peripheral section adjacent to the side edge portion in a second direction, and a narrow section protruding in the first direction from the side edge portion. In the coupling part, the coupling face section is spaced apart from the two bonding parts in a third direction, and the first leg section is connected to the peripheral section of the first bonding part. The first to third directions are perpendicular to one another.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_G?? is 6.1 ([GPa?1·?m?2.5/rad8]·10?12) or less when represented by F?BL_G??=F?BL_G×F?BL_??, where F?BL_G is geometry microbend loss characteristic and F?BL_?? is optical microbend loss characteristic.

Abstract: An optical fiber includes a glass portion, a primary coating layer, and a secondary coating layer. In the optical fiber, a value of microbend loss characteristic factor F?BL_GO is 2.6 ([GPa?1·?m?10.5·dB/turn]·10?27) or less, when represented by F?BL_GO=F?BL_G×F?BL_O by using geometry microbend loss characteristic F?BL_G and optical microbend loss characteristic F?BL_O.