Abstract: A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed.

Abstract: A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed.

Abstract: A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed.

Abstract: This optical waveguide is provided with a slab waveguide in which a grating is formed, an arrayed waveguide connected to a position where a constructive interference portion of a self-image of the grating is formed, and a refractive index change region which is formed between the slab waveguide and the arrayed waveguide, in which an average value of a refractive index in a refractive index distribution in a direction substantially vertical to a light propagation direction is averagely increased from the slab waveguide toward the arrayed waveguide, and in which an average value of the refractive index in a refractive index distribution in a direction substantially parallel to the light propagation direction is increased at a central axis of the arrayed waveguide.

Abstract: An optical waveguide provided with a slab waveguide, which has a plurality of phase gratings arranged at a distance from each other in a direction substantially parallel to a light propagation direction and diffracting propagated light and a plurality of interference regions arranged alternately to the plurality of phase gratings in the direction substantially parallel to the light propagation direction and interfering the light diffracted by the plurality of phase gratings, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position of a constructive interference portion of a self-image formed by the plurality of phase gratings as an integrated phase grating.

Abstract: Provided is a vehicle upper structure which is capable of increasing, in a simple manner, a section modulus (resistive force) against a bending moment to be imposed on a roof reinforcement by a swinging phenomenon of a gusset occurring when a side impact load input into a center pillar and a roof side rail member is applied to the roof reinforcement from the gusset during a vehicle side impact event, to allow the load to be effectively dispersed to the roof reinforcement. The vehicle upper structure comprises a roof side rail member 4, a roof reinforcement 15 and a gusset 30, wherein an end of the gusset 30 on a side fastened to the roof reinforcement 15 has a shape which inclines with respect to a line L1 oriented in a vehicle front-rear direction, in top plan view.

Abstract: Provided is a vehicle upper structure which is capable of increasing, in a simple manner, a section modulus (resistive force) against a bending moment to be imposed on a roof reinforcement by a swinging phenomenon of a gusset occurring when a side impact load input into a center pillar and a roof side rail member is applied to the roof reinforcement from the gusset during a vehicle side impact event, to allow the load to be effectively dispersed to the roof reinforcement. The vehicle upper structure comprises a roof side rail member 4, a roof reinforcement 15 and a gusset 30, wherein an end of the gusset 30 on a side fastened to the roof reinforcement 15 has a shape which inclines with respect to a line L1 oriented in a vehicle front-rear direction, in top plan view.

Abstract: This optical waveguide is provided with a slab waveguide in which a grating is formed, an arrayed waveguide connected to a position where a constructive interference portion of a self-image of the grating is formed, and a refractive index change region which is formed between the slab waveguide and the arrayed waveguide, in which an average value of a refractive index in a refractive index distribution in a direction substantially vertical to a light propagation direction is averagely increased from the slab waveguide toward the arrayed waveguide, and in which an average value of the refractive index in a refractive index distribution in a direction substantially parallel to the light propagation direction is increased at a central axis of the arrayed waveguide.

Abstract: An optical waveguide provided with a slab waveguide, which has a plurality of phase gratings arranged at a distance from each other in a direction substantially parallel to a light propagation direction and diffracting propagated light and a plurality of interference regions arranged alternately to the plurality of phase gratings in the direction substantially parallel to the light propagation direction and interfering the light diffracted by the plurality of phase gratings, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position of a constructive interference portion of a self-image formed by the plurality of phase gratings as an integrated phase grating.

Abstract: A technique that does not increase the circuit size, does not make the circuit design and manufacturing difficult, and can reduce insertion loss when light enters from a slab waveguide toward an arrayed waveguide or when the light enters from the arrayed waveguide toward the slab waveguide. An optical waveguide provided with a slab waveguide in which a grating is formed therein at a distance from an end, and an arrayed waveguide whose end is connected to an end of the slab waveguide at a position where a constructive interference portion of a self-image of the grating is formed.