Abstract: A nonreciprocal waveguide includes a substrate, a light propagation path, a magnetic member, an insulating layer, and a mask. The light propagation path is positioned at the substrate along a substrate surface. The magnetic member is positioned at the substrate along part of the light propagation path in a longitudinal direction. The insulating layer is positioned at the substrate and contains the light propagation path and the magnetic member. Inside the insulating layer, the mask is positioned further away than the light propagation path from the substrate. As seen from a direction perpendicular to the substrate surface, the mask overlaps at least part of the light propagation path in a width direction from a side of the light propagation path opposite to the magnetic member in the width direction. The mask is positioned in at least a range in which the magnetic member is positioned in the longitudinal direction.

Abstract: An isolator includes a first core, a second core, a nonreciprocal member, and a magnetic body. The first core and the second core extend in a first direction and are positioned side by side with a cladding therebetween in a second direction that intersects the first direction. The nonreciprocal member is in contact with at least a part of the second core while being positioned side by side with the second core in the second direction. In a magnetic field generated by the magnetic body in a portion where the nonreciprocal member is positioned, a component in a third direction perpendicular to the first direction and the second direction is greater than any component other than the component in the third direction.

Abstract: The light source device according to the present disclosure includes a light source, a light transmission part, a light intensity converter, and a collimator. The light source includes a plurality of semiconductor laser elements. The collimator includes a first lens array that has a plurality of collimator lenses. Each collimator lens collimates laser light emitted from a single semiconductor laser element. The light intensity converter includes a second lens array that has a plurality of lens arrays. Each lens array includes a plurality of lens cells so as to uniformize a light intensity distribution of the laser beam emitted from the single semiconductor laser element. The light intensity converter is disposed on a main surface of the light transmission part on the light source side. The collimator is disposed on a surface of the light transmission part opposite to the light source side.

Abstract: An isolator includes a substrate, a waveguide and an electronic circuit disposed above the substrate, and a non-reciprocal member disposed above the waveguide and the electronic circuit. The non-reciprocal member includes a first portion in contact with the waveguide and a second portion disposed within a predetermined range from the electronic circuit. Non-reciprocity in the second portion is weaker than non-reciprocity in the first portion.

Abstract: The optical switch 10 comprises a first waveguide 11, a second waveguide 12, and an exchanger 13. The first waveguide 11 comprises a first end E1 and a second end E2. The second waveguide 12 comprises a third end E3 and a fourth end E4, respectively located on the first end E1 side and the second end E2 side as viewed from the center of the first waveguide 11. The exchanger 13 comprises: a first waveguide section 21 configuring a directional coupler together with the first waveguide 11 and including a phase changing material 23; and a second waveguide section 22 configuring a directional coupler together with the second waveguide 12 and including a phase change material 24. The exchanger 13 inputs electromagnetic waves, input from the first end E1 and output from the first waveguide section 21, to the third end E3 side of the second waveguide section 22.

Abstract: An isolator includes a substrate having a substrate surface, a waveguide, a groove, a mask, and a non-reciprocal member. The waveguide is disposed above the substrate surface and has a first surface facing the substrate surface, a second surface opposite the first surface, and a side face connecting the first surface to the second surface. The groove includes a bottom portion and a side portion configured to expose at least part of the side face of the waveguide. The mask is disposed above and overlaps at least a region of the second surface of the waveguide, as viewed in a direction normal to the substrate surface. The region of the second surface of the waveguide is in contact with the groove. The non-reciprocal member is disposed in the groove and is in contact with the side face of the waveguide.

Abstract: A nonreciprocal waveguide includes a substrate, a light propagation path, a magnetic member, an insulating layer, and a mask. The light propagation path is positioned at the substrate along a substrate surface. The magnetic member is positioned at the substrate along part of the light propagation path in a longitudinal direction. The insulating layer is positioned at the substrate and contains the light propagation path and the magnetic member. Inside the insulating layer, the mask is positioned further away than the light propagation path from the substrate. As seen from a direction perpendicular to the substrate surface, the mask overlaps at least part of the light propagation path in a width direction from a side of the light propagation path opposite to the magnetic member in the width direction. The mask is positioned in at least a range in which the magnetic member is positioned in the longitudinal direction.

Abstract: An isolator includes a first core, a second core, a nonreciprocal member, and a magnetic body. The first core and the second core extend in a first direction and are positioned side by side with a cladding therebetween in a second direction that intersects the first direction. The nonreciprocal member is in contact with at least a part of the second core while being positioned side by side with the second core in the second direction. In a magnetic field generated by the magnetic body in a portion where the nonreciprocal member is positioned, a component in a third direction perpendicular to the first direction and the second direction is greater than any component other than the component in the third direction.

Abstract: An optical isolator 10 according to the present disclosure includes a substrate 11 and an optical waveguide 12 provided on the substrate 11. The optical waveguide 12 includes a first end part 13, a plurality of second end parts 14 arranged in an array, and at least one branching part 18 located between the first end part 13 and the plurality of second end parts 14. The optical waveguide 12 has a portion having non-reciprocity and gives different non-reciprocal phase shift amounts between the first end part 13 and at least two of the second end parts 14.

Abstract: An isolator includes a first waveguide with a linear shape and a second waveguide with an annular shape on a substrate including a substrate surface, the first waveguide being positioned along the substrate surface. The first waveguide and the second waveguide each include a core and a cladding. The first waveguide includes a first end, a second end, and a port at each of the first end and the second end for input and output of electromagnetic waves. The core of the second waveguide includes a non-reciprocal member in at least a portion of a cross-section intersecting a direction in which the second waveguide extends.

Abstract: The optical switch 10 comprises a first waveguide 11, a second waveguide 12, and an exchanger 13. The first waveguide 11 comprises a first end E1 and a second end E2. The second waveguide 12 comprises a third end E3 and a fourth end E4, respectively located on the first end E1 side and the second end E2 side as viewed from the center of the first waveguide 11. The exchanger 13 comprises: a first waveguide section 21 configuring a directional coupler together with the first waveguide 11 and including a phase changing material 23; and a second waveguide section 22 configuring a directional coupler together with the second waveguide 12 and including a phase change material 24. The exchanger 13 inputs electromagnetic waves, input from the first end E1 and output from the first waveguide section 21, to the third end E3 side of the second waveguide section 22.

Abstract: In a light source device, and a projection device and a fluorescence excitation device using the same, a light beam emitted from a semiconductor laser is focused at a prescribed focusing position after an aspect ratio of the light beam has been adjusted, by which a spot diameter at the focusing position is reduced. Light source device includes: semiconductor laser; beam shaping lens that adjusts an aspect ratio of light beam emitted from semiconductor laser; and condenser lens that focuses light beam passing through beam shaping lens on prescribed focusing position, wherein beam shaping lens is a cylindrical lens having negative power with respect to a slow axis direction of incident light beam.

Abstract: An isolator includes a first waveguide and a second waveguide on a substrate having a substrate surface, the first waveguide and the second waveguide located along the substrate surface and overlapping each other as viewed from the substrate. The first waveguide and the second waveguide each include a core and a clad. The core has a first surface facing the substrate surface, and a second surface opposite to the first surface. The clad contacts the first surface and the second surface of the core. The first waveguide has a first end and a second end, and has a port for input and output of electromagnetic waves at each of the first end and the second end. The core of the second waveguide includes a non-reciprocal member in at least one part of a cross section intersecting a direction in which the second waveguide extends.

Abstract: A display apparatus includes an image projector and a controller. The image projector emits image projection light that projects an image onto a projection-target surface. The controller controls, in a time division manner, the emission direction of the image projection light emitted by the image projector. The controller performs control to prevent the sum of the area of one or more regions of the projection-target surface, on which the image projection light is projected, from exceeding a predetermined upper limit.

Abstract: An isolator includes a first waveguide and a second waveguide on a substrate having a substrate surface, the first waveguide and the second waveguide located along the substrate surface and overlapping each other as viewed from the substrate. The first waveguide and the second waveguide each include a core and a clad. The core has a first surface facing the substrate surface, and a second surface opposite to the first surface. The clad contacts the first surface and the second surface of the core. The first waveguide has a first end and a second end, and has a port for input and output of electromagnetic waves at each of the first end and the second end. The core of the second waveguide includes a non-reciprocal member in at least one part of a cross section intersecting a direction in which the second waveguide extends.

Abstract: A display apparatus includes an image projector and a controller. The image projector emits image projection light that projects an image onto a projection-target surface. The controller controls, in a time division manner, the emission direction of the image projection light emitted by the image projector. The controller performs control to prevent the sum of the area of one or more regions of the projection-target surface, on which the image projection light is projected, from exceeding a predetermined upper limit.

Abstract: The depth of field of an erecting equal-magnification lens array unit as a whole is expanded. An erecting equal-magnification lens array unit (13) includes a first lens array (17) and a second lens array (18). The first lens array (17) includes a plurality of first lenses (20). The first lenses are arranged in the first lens array (17) along a first direction. The first direction is perpendicular to the optical axes of the first lenses (20). The second lens array (18) includes a plurality of second lenses. The optical axes of the second lenses overlap with the optical axes of the first lenses. The second lenses are arranged in the second lens array (18) along the first direction. Each first lens (20) and second lens with overlapping optical axes form an optical system.

Abstract: An erecting equal-magnification lens array unit includes a first lens array and a second lens array. The first lens array includes a plurality of first lenses. The second lens array includes a plurality of second lenses. The optical axes of the second lenses overlap with the optical axes of the first lenses. Each first lens and second lens with overlapping optical axes form a unit optical system. Each unit optical system is an erecting equal-magnification optical system. Each unit optical system is substantially telecentric on at least the object side. The imaging position, by each first lens, of an object is positioned between the first lens array and the second lens array.

Abstract: The depth of field of an erecting equal-magnification lens array unit as a whole is expanded. An erecting equal-magnification lens array unit (13) includes a first lens array (17) and a second lens array (18). The first lens array (17) includes a plurality of first lenses (20). The first lenses are arranged in the first lens array (17) along a first direction. The first direction is perpendicular to the optical axes of the first lenses (20). The second lens array (18) includes a plurality of second lenses. The optical axes of the second lenses overlap with the optical axes of the first lenses. The second lenses are arranged in the second lens array (18) along the first direction. Each first lens (20) and second lens with overlapping optical axes form an optical system.

Abstract: A wavelength conversion laser light source, includes: a solid laser medium; a wavelength conversion element; a concave mirror on which a first reflecting surface reflecting a fundamental light wave and a the second harmonic light wave is formed; and a wavelength plate on which a second reflecting surface reflecting the fundamental light wave and transmitting the second harmonic light wave is formed, wherein a laser resonator is constituted by the first reflecting surface and the second reflecting surface; the solid laser medium is arranged on a first reflecting surface side of the laser resonator, the wavelength plate is arranged on a second reflecting surface side of the laser resonator, and the wavelength conversion element is arranged between the solid laser medium and the wavelength plate; and the wavelength plate outputs the second harmonic wave, to the exterior of the laser resonator, via the second reflecting surface.