Abstract: A light emitting device includes a wavelength conversion element, and an excitation light source which radiates excitation light to the wavelength conversion element. The wavelength conversion element includes a support member having a supporting surface, and a wavelength conversion member disposed on the supporting surface so as to be contained within the support member when the support member is viewed from the supporting surface side. An outer peripheral region on the support member, which is an outer peripheral portion of an arrangement region including the wavelength conversion member and is exposed from the wavelength conversion member, includes a light absorbing portion which can absorb first light having same wavelength as the excitation light or a light scattering portion which can scatter the first light. The arrangement region includes a reflective member which is disposed between the wavelength conversion member and the support member, and is different from the support member.

Abstract: A light emitting device includes a wavelength conversion element, and an excitation light source which radiates excitation light to the wavelength conversion element. The wavelength conversion element includes a support member having a supporting surface, and a wavelength conversion member disposed on the supporting surface so as to be contained within the support member when the support member is viewed from the supporting surface side. An outer peripheral region on the support member, which is an outer peripheral portion of an arrangement region including the wavelength conversion member and is exposed from the wavelength conversion member, includes a light absorbing portion which can absorb first light having same wavelength as the excitation light or a light scattering portion which can scatter the first light. The arrangement region includes a reflective member which is disposed between the wavelength conversion member and the support member, and is different from the support member.

Abstract: A light emitting device includes a wavelength conversion element, and an excitation light source which radiates excitation light to the wavelength conversion element. The wavelength conversion element includes a support member having a supporting surface, and a wavelength conversion member disposed on the supporting surface so as to be contained within the support member when the support member is viewed from the supporting surface side. An outer peripheral region on the support member, which is an outer peripheral portion of an arrangement region including the wavelength conversion member and is exposed from the wavelength conversion member, includes a light absorbing portion which can absorb first light having same wavelength as the excitation light or a light scattering portion which can scatter the first light. The arrangement region includes a reflective member which is disposed between the wavelength conversion member and the support member, and is different from the support member.

Abstract: A light source device includes: a semiconductor light-emitting device including a flat-shaped base having a first main surface on a first side and a second main surface and a semiconductor light-emitting element disposed on the first side; a first fixing component having a first through-hole and a first pressing surface that presses the first main surface; and a second fixing component having a second through-hole and a second pressing surface that presses the second main surface. The base is fixed between the first and second pressing surfaces by an engagement between a first inner surface surrounding the first through-hole of the first fixing component and a second outer surface of the second fixing component. A distance between the first and second pressing surfaces is smaller than or equal to a thickness of the base, and a void is formed lateral to the base between the first and second pressing surfaces.

Abstract: A light source device includes a semiconductor light-emitting device which emits coherent excitation light, and a wavelength conversion element which is spaced from the semiconductor light-emitting device, generates fluorescence by converting the wavelength of the excitation light emitted from semiconductor light-emitting device, and generates scattered light by scattering the excitation light. The wavelength conversion element includes a support member, and a wavelength converter disposed on the support member. The wavelength converter includes a first wavelength converter, and a second wavelength converter which is disposed around the first wavelength converter to surround the first wavelength converter in a top view of the surface of the support member on which the wavelength converter is disposed. The ratio of the intensity of fluorescence to that of scattered light is lower in the second wavelength converter than in the first wavelength converter.

Abstract: A light source device includes: a semiconductor light-emitting element; a converging optical system which converges the excitation light emitted from the semiconductor light-emitting element; and a wavelength conversion element to which the excitation light is emitted. The wavelength conversion element includes: a first wavelength conversion region where main light enters; and a second wavelength conversion region which is disposed in the surrounding region of the first wavelength conversion region and where the excitation light excluding the main light enters. The wavelength conversion efficiency in the second wavelength conversion region is lower than the wavelength conversion efficiency in the first wavelength conversion region.

Abstract: A light source device includes: a semiconductor light-emitting device including a flat-shaped base having a first main surface on a first side and a second main surface and a semiconductor light-emitting element disposed on the first side; a first fixing component having a first through-hole and a first pressing surface that presses the first main surface; and a second fixing component having a second through-hole and a second pressing surface that presses the second main surface. The base is fixed between the first and second pressing surfaces by an engagement between a first inner surface surrounding the first through-hole of the first fixing component and a second outer surface of the second fixing component. A distance between the first and second pressing surfaces is smaller than or equal to a thickness of the base, and a void is formed lateral to the base between the first and second pressing surfaces.

Abstract: A light emitting device includes a wavelength conversion element, and an excitation light source which radiates excitation light to the wavelength conversion element. The wavelength conversion element includes a support member having a supporting surface, and a wavelength conversion member disposed on the supporting surface so as to be contained within the support member when the support member is viewed from the supporting surface side. An outer peripheral region on the support member, which is an outer peripheral portion of an arrangement region including the wavelength conversion member and is exposed from the wavelength conversion member, includes a light absorbing portion which can absorb first light having same wavelength as the excitation light or a light scattering portion which can scatter the first light. The arrangement region includes a reflective member which is disposed between the wavelength conversion member and the support member, and is different from the support member.

Abstract: A wavelength conversion element includes a support member having a supporting surface, and a wavelength converter disposed above the supporting surface. The wavelength converter contains first fluorescent particles which absorb excitation light and generate fluorescence (second radiation light), and a transparent binder which bonds the first fluorescent particles, and has a joint surface facing supporting surface, and an incident surface disposed opposite to the joint surface, the excitation light entering the incident surface. The excitation light and fluorescence are emitted from the incident surface. The wavelength converter includes projections. At least part of the projections is disposed on the incident surface. The first fluorescent particles are partially exposed from vertices of the projections.

Abstract: In a light source in which a semiconductor luminescence element and a phosphor are combined, red light having high color purity is efficiently radiated. The light source includes: a semiconductor luminescence element; a fixed or rotatable first wavelength converting unit; and a rotatable second wavelength converting unit. The second wavelength converting unit includes: a second wavelength converting region that absorbs output light emitted from the semiconductor luminescence element and radiates light having a second wavelength different from that of the output light; and a transmission region that transmits the output light. The first wavelength converting unit absorbs the output light to radiate light having a first wavelength longer than the second wavelength of the light, and the light having the first wavelength is transmitted through the transmission region.

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 light-emitting device includes: a semiconductor light-emitting element which emits light of a first wavelength; and a first wavelength conversion unit which includes a first phosphor and emits light of a second wavelength by being excited by the light of the first wavelength. The first phosphor contains europium as an activator. The light of the first wavelength is emitted to the first wavelength conversion unit at 1 kW/cm2 or greater. 1??12/?11?1.17 is satisfied where ?1 is light output ratio of the light of the first wavelength to the light of the second wavelength, ?11 is light output ratio obtained when the light of the first wavelength is emitted to the first wavelength conversion unit at 5 kW/cm2, and ?12 is light output ratio obtained when the light of the first wavelength is emitted to the first wavelength conversion unit at 2.5 kW/cm2.

Abstract: In a light source in which a semiconductor luminescence element and a phosphor are combined, red light having high color purity is efficiently radiated. The light source includes: a semiconductor luminescence element; a fixed or rotatable first wavelength converting unit; and a rotatable second wavelength converting unit. The second wavelength converting unit includes: a second wavelength converting region that absorbs output light emitted from the semiconductor luminescence element and radiates light having a second wavelength different from that of the output light; and a transmission region that transmits the output light. The first wavelength converting unit absorbs the output light to radiate light having a first wavelength longer than the second wavelength of the light, and the light having the first wavelength is transmitted through the transmission region.

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 having an optical waveguide includes, in the following order, at least: a first cladding layer; an active layer; and a second cladding layer, wherein the second cladding layer includes (i) a transparent conductive layer comprising a transparent conductor and (ii) a nitride semiconductor layer comprising a nitride semiconductor, the nitride semiconductor layer being formed closer to the active layer than the transparent conductive layer.

Abstract: A light-emitting device includes: a semiconductor light-emitting element which emits light of a first wavelength; and a first wavelength conversion unit which includes a first phosphor and emits light of a second wavelength by being excited by the light of the first wavelength. The first phosphor contains europium as an activator. The light of the first wavelength is emitted to the first wavelength conversion unit at 1 kW/cm2 or greater. 1??12/?11?1.17 is satisfied where ?1 is light output ratio of the light of the first wavelength to the light of the second wavelength, ?11 is light output ratio obtained when the light of the first wavelength is emitted to the first wavelength conversion unit at 5 kW/cm2, and ?12 is light output ratio obtained when the light of the first wavelength is emitted to the first wavelength conversion unit at 2.5 kW/cm2.

Abstract: A nitride semiconductor light-emitting device having an optical waveguide includes, in the following order, at least: a first cladding layer; an active layer; and a second cladding layer, wherein the second cladding layer includes (i) a transparent conductive layer comprising a transparent conductor and (ii) a nitride semiconductor layer comprising a nitride semiconductor, the nitride semiconductor layer being formed closer to the active layer than the transparent conductive layer.

Abstract: A semiconductor laser device includes a semiconductor multilayer structure selectively grown on a substrate other than on a predetermined region of the substrate. The semiconductor multilayer structure includes an active layer, and has a stripe-shaped optical waveguide extending in a direction intersecting a front facet through which light is emitted. The active layer has an abnormal growth portion formed at a peripheral edge of the predetermined region, and a larger forbidden band width portion formed around the abnormal growth portion and having a larger width of a forbidden band than that of a portion other than the abnormal growth portion of the active layer. The optical waveguide is spaced apart from the abnormal growth portion and includes the larger forbidden band width portion at the front facet.

Abstract: A nitride semiconductor device includes a first nitride semiconductor layer formed on a substrate, a defect induced layer formed on the first nitride semiconductor layer, and a second nitride semiconductor layer formed on the defect induced layer, contacting the defect induced layer, and having an opening through which the defect induced layer is exposed. The defect induced layer has a higher crystal defect density than those of the first and second nitride semiconductor layers.

Abstract: A semiconductor light-emitting device includes an n-type cladding layer formed on a substrate, an active layer formed on the n-type cladding layer and including a well layer and a barrier layer, and a p-type cladding layer formed on the active layer. The well layer is made of an indium-containing nitride semiconductor, and has a hydrogen concentration greater than that of the n-type cladding layer and less than that of the p-type cladding layer.