Systems and methods disclosed herein include a vertical cavity surface emitting laser (VCSEL) device that includes an anode, a cathode, and one or more curved apertures located in an epitaxial layer between the anode and the cathode, each of the one or more curved apertures having an aperture edge and one or more oxidation bridges crossing the curved aperture that allow current to flow inside the curved aperture, in which when a current signal is applied to the VCSEL, current flow between the anode and the cathode is distributed along the aperture edge of the one or more curved apertures.

A laser including a grating configured to reduce lasing threshold for a selected vertically confined mode as compared to other vertically confined modes.

A semiconductor optical device includes a first facet bounding a first end of the semiconductor optical device. The semiconductor optical device further includes a waveguide having a first end proximate the first facet, the first end of the waveguide being tapered towards the first facet. The first facet has a curvature to increase modal reflectivity at a first interface at which the first end of the waveguide meets the first facet.

A vertical cavity surface emitting device includes a substrate, a first multilayer film reflecting mirror, a light-emitting structure layer with a light-emitting layer, and a second multilayer film reflecting mirror. The second multilayer film reflecting mirror constitutes a resonator between the first and second multilayer film reflecting mirrors. The second multilayer film reflecting mirror includes a first multilayer film, an intermediate film, and a second multilayer film. The first and second multilayer films have low refractive index films and high refractive index films that are alternately stacked. The intermediate film covers an upper surface of the first multilayer film and film has a translucency to a light emitted from the light-emitting layer. The second multilayer film partially covers an upper surface of the intermediate film. The intermediate film has a film thickness based on ½ of a wavelength inside the intermediate film of light emitted from the light-emitting layer.

A surface-emitting semiconductor laser includes a substrate, a first electrode in contact with the substrate, a first light reflection layer over the substrate, a second light reflection layer over the substrate, with the first light reflection layer between the second light reflection layer and the substrate, an active layer between the second light reflection layer and the first light reflection layer, a current confining layer between the active layer and the second light reflection layer and includes a current injection region, a second electrode over the substrate, with the second light reflection layer between the second electrode and the substrate, at least a portion of the second electrode is at a position overlapping the current injection region, and a contact layer between the second electrode and the second light reflection layer and includes a contact region in contact with the second electrode.

A light emitting element includes an active layer; and a first reflecting mirror over the active layer. The first reflecting mirror includes a multilayer-film reflecting mirror and a first layer on a first surface. The multilayer-film reflecting mirror has the first surface and a second surface closer to the active layer than the first surface, and includes a first refractive-index layer having a first refractive index; and a second refractive-index layer having a second refractive index higher than the first refractive index. The first refractive-index layer and the second refractive-index layer are alternately stacked. The first surface has an emission region from which the light generated in the active layer is emitted. The first layer is in the emission region of the first surface and is configured to absorb a portion of the light emitted from the first surface and transmit another portion of the light through the first layer.

In an embodiment, the gain-guided semiconductor laser includes a semiconductor layer sequence and electrical contact pads. The semiconductor layer sequence includes an active zone for radiation generation, a waveguide layer, and a cladding layer. The semiconductor layer sequence further includes a current diaphragm layer which is electrically conductive along a resonator axis (R) in a central region and electrically insulating in adjoining edge regions. Transverse to the resonator axis (R), the central region includes a width of at least 10 μm and the edge regions includes at least a minimum width. The minimum width is 3 μm or more. Seen in plan view, the semiconductor layer sequence as well as at least one of the contact pads on the semiconductor layer sequence are continuous components extending in the central region as well as on both sides at least up to the minimum width in the direction transverse to the resonator axis adjoining the central region and beyond the central region.

A semiconductor laser element includes: a first conductivity-type cladding layer; a first guide layer disposed above the first conductivity-type cladding layer; an active layer disposed above the first guide layer; and a second conductivity-type cladding layer disposed above the active layer. A window region is formed in a region of the active layer including part of at least one of the front-side end face or the rear-side end face, the first conductivity-type cladding layer consists of (Al.sub.xGa.sub.1-x).sub.0.5In.sub.0.5P, the first guide layer consists of (Al.sub.yGa.sub.1-y).sub.0.5In.sub.0.5P, and the second conductivity-type cladding layer consists of (Al.sub.zGa.sub.1-z).sub.0.5In.sub.0.5P, where x, y, and z each denote an Al composition ratio, 0<x−y<z−y is satisfied, and D/L>0.03 is satisfied, where L denotes a length of the resonator and D denotes a length of the window region in the first direction.

A vertical cavity surface emitting device includes a substrate, a first multilayer film reflecting mirror formed on the substrate, a light-emitting structure layer formed on the first multilayer film reflecting mirror and including a light-emitting layer, and a second multilayer film reflecting mirror formed on the light-emitting structure layer. A resonator is constituted between the second multilayer film reflecting mirror and the first multilayer film reflecting mirror. The light-emitting structure layer includes a low resistance region and a high resistance region. The low resistance region is disposed in a ring shape between the first multilayer film reflecting mirror and the second multilayer film reflecting mirror. The high resistance region is formed inside the low resistance region and has an electrical resistance higher than an electrical resistance of the low resistance region.

A light-emitting device includes: a first light source that oscillates in a single lateral mode; a second light source that oscillates in a multiple lateral mode, the second light source having a light output larger than a light output of the first light source and being configured to be driven independently from the first light source; and a light diffusion member that is provided on an emission path of the second light source.