Abstract: A light-emitting device comprises a layered structure between a first layer and a second layer. The first layer has a refractive index n1 for first light having a wavelength ?a in air. The second layer has a refractive index n2 for the first light. The layered structure comprises: a photoluminescent layer having a first surface facing the first layer and a second surface facing the second layer; and a surface structure disposed on at least one selected from the group consisting of the first surface and the second surface of the photoluminescent layer. The refractive index n1 and the refractive index n2 are lower than a refractive index nwav-a of the photoluminescent layer for the first light. The layered structure has an effective thickness to more strongly emit TE polarized light than TM polarized light.

Abstract: An optical scanning system comprises an optical scanning device and a photoreceiver device. The optical scanning device includes a first waveguide array including a plurality of first waveguides through which light beams propagate and from which the light beams are emitted as emission light in an emission direction crossing a propagation direction of the light beams. The photoreceiver device includes a second waveguide array including a plurality of second waveguides disposed in areas on which, when the emission light from the plurality of first waveguides is reflected as reflected light from a target object, the reflected light is incident, the plurality of second waveguides configured to receive the reflected light to propagate the received reflected light as propagating light beams. An array pitch of the plurality of first waveguides in the optical scanning device differs from an array pitch of the plurality of second waveguides in the photoreceiver device.

Abstract: An optical device comprises: a light reflection film which includes a metal layer and a dielectric layer on the metal layer; and a phosphor layer which is located on the dielectric layer and which emits light by being excited by light from a light source. The dielectric layer is located between the metal layer and the phosphor layer. A first wavelength, at which a reflectivity of light vertically incident on the light reflection film from the phosphor layer is highest, is longer than a centroid wavelength of an emission spectrum of the phosphor layer. The dielectric layer has a layered structure comprising a plurality of layers composed of at least two but no more than six layers. Refractive indexes of any two adjacent layers of the plurality of layers are different from each other.

Abstract: An optical scanning device comprises a waveguide array, a first adjusting element, a plurality of phase shifters, a second adjusting element, and a control circuit. When light emitted from the waveguide array forms a light spot on a virtual plane that is spaced apart from the waveguide array, the control circuit causes the light spot to move in first and second directions such that the distance of movement of the light spot from start to finish of scanning of a target region is greater in first one of the first and second directions than in second one of the first and second directions.

Abstract: An imaging system includes a light-emitting device, an image sensor, and a control circuit. The light-emitting device includes a light source, a first waveguide that propagates light from the light source by means of total reflection, a second waveguide, and a first adjustment element. The control circuit causes the light source to repeatedly emit light pulses. Further, the control circuit causes at least some of the plurality of photo-detection cells to accumulate the signal charge in synchronization with the emission of the light pulses and thereby causes the image sensor to generate every first period of time a frame based on the signal charge thus accumulated. Furthermore, the control circuit causes the first adjustment element to change the direction of the emitted light from the second waveguide every second period of time that is shorter than or equal to half the first period of time.

Abstract: A display apparatus includes an excitation light source that outputs excitation light; a light-emitting device including a photoluminescent layer that receives the excitation light and emits light including first light having a wavelength ?a in air, and a light-transmissive layer located on or near the photoluminescent layer; and an optical shutter on an optical path of the light emitted from the photoluminescent layer. A surface structure is defined on at least one of the photoluminescent layer and the light-transmissive layer, and the surface structure has projections or recesses or both and limits a directional angle of the first light having the wavelength ?a in air.

Abstract: A light-emitting device includes a photoluminescent layer and a light-transmissive layer located on the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a submicron structure having at least projections or recesses arranged perpendicular to the thickness direction of the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a light emitting surface. The first light has a wavelength ?a in air. A distance Dint between adjacent projections or recesses and a refractive index nwav-a of the photoluminescent layer for the first light satisfy ?a/nwav-a<Dint<?a. A thickness of the photoluminescent layer, the refractive index nwav-a, and the distance Dint are set to limit a directional angle of the first light emitted from the light emitting surface.

Abstract: A light-emitting apparatus comprising a photoluminescent layer that emits light in response to excitation light and has a light-emitting surface, the light from the photoluminescent layer being emitted through the light-emitting surface. The light-emitting surface includes a first region and a second region. The light from the photoluminescent layer includes first light having a wavelength ?a in air. The first light emitted through the first region has a smaller directional angle than the first light emitted through the second region.

Abstract: A light-emitting apparatus includes a light-emitting device and an excitation light source. The light-emitting device includes a photoluminescent layer, a light-transmissive layer. At least one of the photoluminescent layer and the light-transmissive layer has a submicron structure having at least projections or recesses. Light emitted from the photoluminescent layer includes first light having a wavelength ?a in air. The distance Dint between adjacent projections or recesses and the refractive index nwav-a of the photoluminescent layer for the first light satisfy ?a/nwav-a<Dint<?a. A thickness of the photoluminescent layer, the refractive index nwav-a, and the distance Dint are set to limit a directional angle of the first light emitted from the light emitting surface. The excitation light source emits excitation light. The light-emitting device is integrally provided with the excitation light source.

Abstract: A light-emitting device includes: a photoluminescent layer that emits light; and a light-transmissive layer on which the emitted light is to be incident. At least one of the photoluminescent layer and the light-transmissive layer defines a surface structure. The surface structure has projections and/or recesses to limit a directional angle of the emitted light. The photoluminescent layer and the light-transmissive layer are curved.

Abstract: A light-emitting device includes a photoluminescent layer, a light-transmissive layer located on the photoluminescent layer, and a multilayer mirror layered together with the photoluminescent layer and the light-transmissive layer. At least one of the photoluminescent layer and the light-transmissive layer has a submicron structure. The submicron structure has at least projections or recesses arranged perpendicular to the thickness direction of the photoluminescent layer. The photoluminescent layer emits light including first light having a wavelength ?a in air. The distance Dint between adjacent projections or recesses and the refractive index nwav-a of the photoluminescent layer for the first light satisfy ?a/nwav-a<Dint<?a. A thickness of the photoluminescent layer, the refractive index nwav-a, and the distance Dint are set to limit a directional angle of the first light emitted from the light emitting surface.

Abstract: A light-emitting device comprises a layered structure between a first layer and a second layer. The first first layer has a refractive index n1 for first light having a wavelength ?a in air. The second layer has a refractive index n2 for the first light. The layered structure comprises: a photoluminescent layer having a first surface facing the first layer and a second surface facing the second layer; and a surface structure disposed on at least one selected from the group consisting of the first surface and the second surface of the photoluminescent layer. The refractive index n1 and the refractive index n2 are lower than a refractive index nwav-a of the photoluminescent layer for the first light. The layered structure has an effective thickness to more strongly emit TE polarized light than TM polarized light.

Abstract: A light-emitting device includes a photoluminescent layer that emits light containing first light, a light-transmissive layer located on or near the photoluminescent layer, a low-refractive-index layer and a high-refractive-index layer. A submicron structure is defined on the photoluminescent layer and/or the light-transmissive layer. The low-refractive-index layer is located on or near the photoluminescent layer so that the photoluminescent layer is located between the low-refractive-index layer and light-transmissive layer. The high-refractive-index layer is located on or near the low-refractive-index layer so that the low-refractive-index layer is located between the high-refractive-index layer and the photoluminescent layer.

Abstract: A light-emitting device includes: a light-transmissive layer having a first surface; and a photoluminescent layer located on the first surface. The photoluminescent layer has a second surface facing the light-transmissive layer and a third surface opposite the second surface, and emits light containing first light having a wavelength X, in air from the third surface. The photoluminescent layer has a first surface structure located on the third surface, the first surface structure having an array of projections. The light-transmissive layer has a second surface structure located on the first surface, the second surface structure having projections corresponding to the projections of the first surface structure. The first surface structure and the second surface structure limit a directional angle of the first light emitted from the third surface. The projections of the first surface structure include a first projection, and the first projection has a base width greater than a top width.

Abstract: A light-emitting device includes; a photoluminescent layer that emits light; and a light-transmissive layer on which the emitted light is to be incident. At least one of the photoluminescent layer and the light-transmissive layer defines a surface structure. The surface structure has projections and/or recesses to limit a directional angle of the emitted light. The photoluminescent layer and the light-transmissive layer are curved.

Abstract: A light-emitting apparatus includes an excitation light source that emits first light; a light-emitting device on an optical path of the first light, the light-emitting device emitting second light having a wavelength in air; and a first converging lens on an optical path of the second light. The light-emitting device comprises: a photoluminescent layer that emits the second light by being excited by the first light; and a light-transmissive layer on the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a surface structure comprising projections or recesses arranged perpendicular to a thickness direction of the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a light emitting surface perpendicular to the thickness direction, the second light emitted from the light emitting surface. The surface structure limits the directional angle of the second light emittied from the light emitting surface.

Abstract: A light-emitting device includes a photoluminescent layer that emits light containing first light, a light-transmissive layer located on or near the photoluminescent layer, and one or more reflectors. A submicron structure is defined on at least one of the photoluminescent layer and the light-transmissive layer. The one or more reflector are located outside the submicron structure. The submicron structure includes at least projections or recesses and satisfies the following relationship: ?a/nwav-a<Dint<?a where Dint is a center-to-center distance between adjacent projections or recesses, ?a is the wavelength of the first light in air, and nwav-a is the refractive index of the photoluminescent layer for the first light.

Abstract: A light-emitting device comprises a photoluminescent layer that emits light including first light in an infrared region; and a light-transmissive layer located on the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a periodic structure having projections or recesses or both arranged perpendicular to the thickness direction of the photoluminescent layer. At least one of the photoluminescent layer and the light-transmissive layer has a light emitting surface perpendicular to the thickness direction of the photoluminescent layer, the first light being emitted from the light emitting surface. A refractive index nwav-a of the photoluminescent layer for the first light and a period pa of the periodic structure satisfy ?a/nwav-a<pa<?a. A thickness of the photoluminescent layer, the refractive index nwav-a and the period pa are set to limit a directional angle of the first light emitted from the light emitting surface.

Abstract: A light-emitting apparatus comprising a photoluminescent layer that emits light in response to excitation light and has a light-emitting surface, the light from the photoluminescent layer being emitted through the light-emitting surface. The light-emitting surface includes a first region and a second region. The light from the photoluminescent layer includes first light having a wavelength ?a in air. The first light emitted through the first region has a smaller directional angle than the first light emitted through the second region.

Abstract: A light-emitting device includes a photoluminescent layer that emits light containing first light, and a light-transmissive layer located on or near the photoluminescent layer. A submicron structure is defined on at least one of the photoluminescent layer and the light-transmissive layer. The submicron structure includes at least projections or recesses. The submicron structure has spatial frequency components distributed at least from more than 0 to 2/Dint(min) as determined by two-dimensional Fourier transform of a pattern of the projections or recesses and satisfies the following relationship: 0.8Dint(min)<?a/nwav-a where Dint(min) is the minimum center-to-center distance between adjacent projections or recesses, ?a is the wavelength of the first light in air, and nwav-a is the refractive index of the photoluminescent layer for the first light.