A wavelength converter includes a base having a first surface, a wavelength conversion part that has a second surface facing the first surface and converts first light that belongs to a second wavelength band into fluorescence that belongs to a second wavelength band different from the first wavelength band, junctions that join the wavelength conversion part and the base to each other, and an air layer located in a region that the first light enters and surrounded by the wavelength conversion part, the base, and the junctions. The first surface of the base has a first region curved in a direction, and the second surface of the wavelength conversion part has a second region facing the first region and curved in the same direction.

A light-source device, an image projection apparatus, and a display device. The light-source device includes a light source to emit light, an optical element having a lens array on one side or both sides of which a plurality of lenses are arrayed with distance from each other, the distance between a pair of vertices of an adjacent pair of the plurality of lenses of the optical element being equal to or less than one-quarter of width of light flux of the light incident on the optical element, and a wavelength conversion element to convert a wavelength of the light emitted from the light source and passed through the optical element. An image projection apparatus includes the light-source device, a light mixing element to mix the light emitted from the light-source device to uniformize the light, and an illumination optical system to emit the light uniformized by the light mixing element.

The invention provides a lighting device (1) comprising: —one or more light sources (10) configured to provide light source light (11); —a luminescent element (5) comprising an elongated luminescent body (100) having a radiation input face (111) for receipt of the light source light (11), the luminescent element (5) comprising a first luminescent material (120) for conversion of at least part of the light source light (11) into luminescent material light (8); —a light guide element (850), configured downstream of the first luminescent material (120), and configured to light guide at least part of the first luminescent material light (8); —a second luminescent material (1120), configured downstream of the first 10 luminescent material (120), at a first distance (d1) of at least 0.5 mm thereof, configured to convert one or more of (i) at least part of the light source light (11) and (ii) at least part of the first luminescent material light (8) into second luminescent material light (1128) having a spectral power distribution differing from a spectral power distribution of the first luminescent material light (8); 15—a light transmissive optical element (24) configured downstream of the light guide element (850), configured to receive at least part of the first luminescent material light (8) of the light guide element (850) and to receive at least part of the second luminescent material light (1128), and configured to transmit the received luminescent material light (8) and the received second luminescent material light (1128), and configured to beam shape at least part of the received luminescent material light (8), and to provide lighting device light (101) comprising one or more of the light source light (11), the first luminescent material light (8) and the second luminescent material light (1128).

A wavelength conversion device includes a substrate, a reflective layer, a phosphor layer and a thermal conductive layer. The substrate has a surface. The reflective layer is disposed on the surface of the substrate. The phosphor layer is disposed on the reflective layer and has a conversion region configured to perform a wavelength conversion. The thermal conductive layer is disposed on the surface of the substrate and thermally directly connected to the conversion region for conducting a heat generated at the conversion region during the wavelength conversion. The thermal resistance of the reflective layer is high and causes heat in the conversion region to accumulate. By disposing the thermal conductive layer adjacent to a side of the phosphor layer, the thermal conductive layer is thermally directly connected to the conversion region, so that the heat generated at the conversion region during the wavelength conversion is efficiently dissipated.

A wavelength conversion element includes a substrate, an adhesion layer and a wavelength conversion material. The substrate has a bearing surface having an adhesion zone. The adhesion zone has a central portion and two edge portions respectively on two sides of the central portion. The adhesion layer is disposed on the adhesion zone and includes a first adhesive and a second adhesive. The first adhesive is disposed at the edge portions. The second adhesive is disposed at the central portion. Operating temperature of the first adhesive is lower than operating temperature of the second adhesive. Viscosity of the first adhesive is larger than viscosity of the second adhesive. The wavelength conversion material is fixed on the bearing surface by the first adhesive and the second adhesive. A projection apparatus having the wavelength conversion element is provided, and the durability of the wavelength conversion element and the projection apparatus is improved.

A wavelength conversion element includes a substrate, a wavelength conversion layer and a fixed ring. The fixed ring has a first surface, a second surface, and a plurality of flow guiding structures. The second surface has a first region and a second region. The plurality of flow guiding structures is located on the first surface, and each of the plurality of flow guiding structures is formed with a first flow guiding hole. The first flow guiding hole extends from the first surface to the second region of the second surface. The plurality of flow guiding structures respectively have a spoiler surface, the spoiler surface stands on the first surface and has a second flow guiding hole, in which the second flow guiding hole and the first flow guiding hole of each of the plurality of flow guiding structures face different directions. A projection device of the invention is further provided.

A wavelength conversion element includes a wavelength conversion plate, a fixing ring and an adhesive layer. The wavelength conversion plate has a supporting surface. The fixing ring is disposed on the supporting surface. The adhesive layer is configured to adhere the fixing ring to the wavelength conversion plate. The adhesive layer includes a first adhesive portion and a second adhesive portion, and a density of the first adhesive portion is greater than a density of the second adhesive portion. A projection device including the aforementioned wavelength conversion element is also provided. The wavelength conversion element and the projection device provided by the invention have the advantages of short manufacturing process time and low cost.

A light source apparatus includes an enclosure, a phosphor wheel including a phosphor and disposed in the enclosure, a wheel-side heat dissipater that includes a plurality of fins provided at the phosphor wheel and generates an airflow flowing from the side facing the center of the phosphor wheel toward the periphery thereof with the aid of rotation of the phosphor wheel, a driver that rotates the phosphor wheel, a heat receiving member that includes a placement section where the driver is placed and faces the wheel-side heat dissipater, a heat sink coupled to a side of the heat receiving member, the side opposite to the phosphor wheel, and disposed outside the enclosure, and a plurality of columnar protrusions that are provided around the placement section and protrude into the enclosure toward the plurality of fins.

A light source apparatus (1) according to the present disclosure includes a wavelength conversion device (10) that includes two or more wavelength conversion units (11-13) serially coupled in a first direction. The wavelength conversion device (10) has a configuration in which the two or more wavelength conversion units (11-13) generate respective converted lights having wavelengths different from each other to generate two or more converted lights. The two or more wavelength conversion units (11-13) each include a first end surface and a second end surface that are formed in a direction parallel to the first direction, and a light entering surface (43) that is formed in a second direction different from the first direction and which an excitation light for generating the converted light enters. The first end surface (41) of one wavelength conversion unit (13) positioned at one end of the wavelength conversion device (10) of the two or more wavelength conversion units (11-13) is configured to be a light extraction surface from which the two or more converted lights are extracted out of the excitation light and the two or more converted lights.

A light source apparatus includes a plurality of light emitting apparatuses. Each of the light emitting apparatuses includes a plurality of light emitting devices each of which has a light emitting area and a non-light emitting area on an emission surface thereof that emits light. At least two light emitting apparatuses of the light emitting apparatuses constitute a light emitting apparatus group disposed such that the emission surfaces of the respective light emitting apparatuses are parallel to each other with a predetermined distance, and that a distance between light emitting areas of the respective light emitting apparatuses when viewed along a direction perpendicular to the emission surfaces of the at least two of the light emitting apparatuses is shorter than a distance between the light emitting areas of the respective light emitting apparatuses when the emission surfaces of the respective light emitting apparatuses are on the same plane.