A semiconductor laser device includes an optical waveguide that extends toward a first end of the semiconductor laser device. The optical waveguide includes a first clad layer, an active layer, a second clad layer, and an electrode layer in this order. A reflecting surface, which has a dielectric film and a metal film in this order from the active layer, crosses the active layer at a second end of the optical waveguide.

A quantum cascade laser includes a laser structure having an output face for emitting laser light in a first direction; and a lens having an entrance surface and a convex surface, the entrance surface receiving the laser light from the output face, and the convex surface emitting the laser light after being condensed by the lens. The laser structure includes a semiconductor substrate and a mesa waveguide provided on a first region of a principal surface of the semiconductor substrate, the mesa waveguide extending in the first direction. The lens includes a semiconductor and is provided on a second region of the principal surface of the semiconductor substrate. The first region and the second region are arranged in the first direction.

A quantum cascade laser includes a laser structure having an output face for emitting laser light in a first direction, and a reflecting film provided on the output face. The laser structure includes a core layer. The output face includes an end face of the core layer. The end face includes a first region and a second region that differs from the first region. The reflecting film covers the first region and does not cover the second region.

A surface-emitting semiconductor laser includes a semiconductor laminated structure that includes a first-conductivity-type layer, an active layer, and a second-conductivity-type layer and in which light generated in the active layer is extracted as laser light from a side of the second-conductivity-type layer while resonating along a lamination direction of these layers, a current constriction layer in which the active layer and the second-conductivity-type layer are electrically connected together through an opening, an insulating layer that has translucency with respect to an emission wavelength of the active layer, a first electrode electrically connected to the first-conductivity-type layer, and a second electrode electrically connected to the second-conductivity-type layer, and, in the surface-emitting semiconductor laser, a part of the insulating layer is exposed from the second electrode, and the insulating layer exposed from the second electrode includes a first portion that has a first thickness and a second portion that has a second thickness to make output of light emitted from the active layer smaller than the first portion in comparison with the first thickness and that surrounds the first portion.

A light emitting device includes a substrate; a semiconductor light emitting element provided on the substrate; a mirror that is formed on the substrate and reflects light emitted by the semiconductor light emitting element; a first resin disposed apart from the semiconductor light emitting element on an optical path and containing a light diffusing material; and a second resin disposed on the optical path between the semiconductor light emitting element and the low light diffusion portion and covering a light emitting surface of the semiconductor light emitting element at least in a region in which a density of the light is highest. A concentration of a light diffusing material in the second resin is lower than a concentration of the light diffusing material in the first resin.

A light-emitting element includes: a substrate; a semiconductor chip, formed over the substrate, that includes a plurality of semiconductor layers; a first protective film formed on a first end face of the semiconductor chip that includes a luminous point from which light is emitted; and a first light-absorbing film formed on a part of a surface of the first protective film. The first light-absorbing film covers a part of the surface of the first protective film excluding a portion of the surface through which light emitted from the luminous point passes.

The present embodiment relates to a semiconductor light-emitting element or the like including a structure for suppressing deterioration in the quality of an optical image caused by an electrode blocking a part of light outputted from a phase modulation layer. The semiconductor light-emitting element includes a phase modulation layer having a basic layer and a plurality of modified refractive index regions, and the phase modulation layer includes a first region at least partially overlapping the electrode along a lamination direction and a second region other than the first region. Among the plurality of modified refractive index regions, only one or more modified refractive index regions in the second region are disposed so as to contribute to formation of an optical image.

A light emitting apparatus includes: a submount including a mounting face and an end face, and the end face having an upper edge apart from a front edge of the mounting face; and a quantum cascade laser disposed on the front edge and the mounting face. The quantum cascade laser includes: a laser structure having first, and second faces; a first electrode on the first face; a second electrode on the second face; and a reflecting structure on a first end face of the laser structure. The reflecting structure includes an insulating film having a first end on the first face and a second end on the second face, and a metal film having a first end on the first face, and a second end on the second face. The insulating film is disposed between the laser structure and the first end and the second end of the metal film.

A low numerical aperture fiber output diode laser module, which having several independent diode lasers, and collimated and converged the light beam, for the coupling the light to the core optical fiber with a core diameter of 105 um and a numerical aperture of 0.12. Compared with general products with a numerical aperture of 0.22, the light output angle is reduced to 55%, and use a general blue laser diode for verification. Use an optical software for facilitating the design and optimization of the parameters of the optical lens module.

A light-emitting device is provided. The light-emitting device comprises: a substrate; and multiple radiation emitting regions arranged on the substrate, and comprising: a first radiation emitting region capable of emitting coherent light and emits a coherent light when driven by a first current; a second radiation emitting region capable of emitting coherent light and emits an incoherent light when driven by the first current, wherein each of the first radiation emitting region and the second emitting region comprises epitaxial structure comprising a first DBR stack, a light-emitting structure, and a second DBR stack.