Abstract: A nitride semiconductor laser element includes an electron barrier layer between a p-side light guide layer and a p-type clad layer. The electron barrier layer has a bandgap energy larger than that of the p-type clad layer. The p-side light guide layer is made of AlxGa1?xN containing no Indium, where 0?x<1. A film thickness dn of the n-side light guide layer and a film thickness dp of the p-side light guide layer satisfy relationships dp?0.25 ?m and dn?dp.

Abstract: A semiconductor light emitting device includes a mount section having an insulating property connected to a heat sink, a plurality of semiconductor laser elements disposed on the mount section, and a heat radiation block having an insulating property disposed on the plurality of semiconductor laser elements. A first wiring made of a metal is disposed on an upper surface of the mount section, and a second wiring made of a metal is disposed on a lower surface of the heat radiation block, a part of the second wiring being electrically connected to the first wiring. By electrically connecting the first wiring and the second wiring to each of the plurality of semiconductor laser elements, the plurality of semiconductor laser elements are connected in series, and have a same polarity with each other at a side that each of the plurality of semiconductor laser elements is connected to the first wiring.

Abstract: A nitride semiconductor laser element includes an electron barrier layer between a p-side light guide layer and a p-type clad layer. The electron barrier layer has a bandgap energy larger than that of the p-type clad layer. The p-side light guide layer is made of AlxGa1?xN containing no Indium, where 0 ?x<1. A film thickness dn of the n-side light guide layer and a film thickness dp of the p-side light guide layer satisfy relationships dp?0.25 ?m and dn?dp.

Abstract: A semiconductor light emitting element includes an n-type light guide layer containing a group III nitride semiconductor, an active layer, and a p-type light guide layer, in which the n-type light guide layer includes a semiconductor superlattice layer which is a stack of superlattice layers, the semiconductor superlattice layer having a structure in which group III nitride semiconductors A and group III nitride semiconductors B are alternately stacked, each of the semiconductors A and each of the semiconductors B being stacked in each of the superlattice layers, a relationship Eg (A)>Eg (B) holds, the semiconductor A is a film containing AlInN, and the film contains oxygen (O) at a concentration of at least 1×1018 cm?3, the semiconductor A has a film thickness of at most 5 nm, and a current is injected in a stacking direction of the superlattice layers.

Abstract: An optical irradiation apparatus includes: a light-emitting device configured to emit a plurality of light beams whose optical axes extend in a substantially identical direction; a collimator part configured to convert the light beams into parallel light beams; and a light condensing part configured to collect the parallel light beams. The light-emitting device includes a super luminescent diode array in which a plurality of waveguides are provided on a substrate. Each of the waveguides has a light-emitting facet including a light emission point from which an associated one of the light beams is emitted. The light emission points are located in a plane. The plane including the light emission points is orthogonal to a direction of an optical axis of the collimator part.

Abstract: A semiconductor light emitting element includes an n-type light guide layer containing a group III nitride semiconductor, an active layer, and a p-type light guide layer, in which the n-type light guide layer includes a semiconductor superlattice layer which is a stack of superlattice layers, the semiconductor superlattice layer having a structure in which group III nitride semiconductors A and group III nitride semiconductors B are alternately stacked, each of the semiconductors A and each of the semiconductors B being stacked in each of the superlattice layers, a relationship Eg (A)>Eg (B) holds, the semiconductor A is a film containing AlInN, and the film contains oxygen (O) at a concentration of at least 1×1018 cm?3, the semiconductor A has a film thickness of at most 5 nm, and a current is injected in a stacking direction of the superlattice layers.

Abstract: A nitride semiconductor light emitting device includes: an uneven substrate having an uneven structure in which recesses are formed; a first nitride semiconductor layer of a first conductive type formed on the uneven structure; a first light emitting layer formed on the first nitride semiconductor layer; and a second nitride semiconductor layer of a second conductive type formed on the light emitting layer, wherein each protrusion has a bottom made of a material or composition having a thermal expansion coefficient larger than the thermal expansion coefficient of the material or composition of the first nitride semiconductor layer.

Abstract: A superluminescent diode has, above a substrate, a layered portion including at least a first cladding layer, a luminescent layer, and a second cladding layer in this order, and an optical waveguide having a refractive-index guiding structure is provided in the layered portion. The optical waveguide includes: a first mesa portion formed by processing the second cladding layer into the first mesa portion having a first width; and a second mesa portion formed by processing the first cladding layer, the luminescent layer, and the second cladding layer into the second mesa portion having a second width greater than the first width.

Abstract: An optical irradiation apparatus includes: a light-emitting device configured to emit a plurality of light beams whose optical axes extend in a substantially identical direction; a collimator part configured to convert the light beams into parallel light beams; and a light condensing part configured to collect the parallel light beams. The light-emitting device includes a super luminescent diode array in which a plurality of waveguides are provided on a substrate. Each of the waveguides has a light-emitting facet including a light emission point from which an associated one of the light beams is emitted. The light emission points are located in a plane. The plane including the light emission points is orthogonal to a direction of an optical axis of the collimator part.