A light source device according to the present disclosure includes a first light source section for emitting a first light flux, a second light source section for emitting a second light flux, a third light source section for emitting a third light flux, a first reflecting member, a second reflecting member for reflecting the second light flux, and a polarization combining element. With respect to the polarization combining element, the first light flux and the second light flux are light polarized in a first polarization direction, and the third light flux is light polarized in a second polarization direction, and the first and second reflecting members are disposed so that a distance between the first light flux and second light flux becomes smaller after incidence than before the incidence. The polarization combining element combines the first light flux, the second light flux, and the third light flux with each other.

A light source device according to an embodiment of the present disclosure includes: a first light source section that emits light in a first wavelength region; a wavelength conversion section that is disposed on an optical path of the light in the first wavelength region, and is excited by the light in the first wavelength region emitted from the first light source section to emit light in a second wavelength region different from the first wavelength region; a polarization separation element that is disposed between the first light source section and the wavelength conversion section, and separates incident light on the basis of polarization; and a color separation element that is disposed between the first light source section and the polarization separation element, and separates incident light on the basis of a wavelength region.

A wavelength conversion element according to the present disclosure includes a wavelength conversion layer having a first surface having a recessed part, and a plurality of air holes, and configured to be excited by light in a first wavelength band to thereby generate light in a second wavelength band different from the first wavelength band, a particle disposed in the recessed part, a light transmissive member disposed so as to cover the recessed part and the particle, a reflecting layer disposed so as to be opposed to the first surface of the wavelength conversion layer, and a base member disposed so as to be opposed to the reflecting layer.

A projection apparatus includes a light source for emitting light with an initial spectral distribution, an optical element, and a projection surface. The optical element is arranged in a beam path of light emitted from the light source between the light source and the projection surface. The optical element includes a number of pixels. The pixels of the optical element are each configured to convert light with the initial spectral distribution into light with a predetermined final spectral distribution different from the initial spectral distribution.

Provided is a wavelength conversion member including a ceramic layer as a reflective layer and having excellent luminescence intensity and a light emitting device using the same. A wavelength conversion member 10 including: a first porous ceramic layer 1 having a porosity of 20% by volume or more; and a phosphor layer 2 formed on a principal surface 1a of the first porous ceramic layer 1.

The disclosure provides a display unit and a projection device. The display unit includes a first display panel having first light emitting elements configured to provide a first color light, a wavelength conversion element located on a transmission path of the first color light and having a conversion region and a non-conversion region, a second display panel having second light emitting elements configured to provide a second color light, and a light combining element. A quantum dot conversion material is disposed on the conversion region. Part of the first color light is converted into a third color light after passing through the conversion region, and another part of the first color light passes through the non-conversion region. The light combining element is located on transmission paths of the first color light, the second color light and the third color light and is configured to form an image beam.

The laser projection apparatus includes a laser source, an optical engine and a projection lens. The laser source includes a base plate, a plurality of light-emitting components and a reflecting portion. The plurality of light-emitting components include a first light-emitting component and a second light-emitting component. The polarization direction of the laser beam emitted by one of the first light-emitting component and the second light-emitting component is parallel to the base plate, and the polarization direction of the laser beam emitted by another of the first light-emitting component and the second light-emitting component is perpendicular to the base plate. The reflecting prism is configured to change a polarization polarity of one of the laser beam with the polarization direction perpendicular to the base plate or the laser beam with the polarization direction parallel to the base plate.

An image display system includes semiconductor light sources that output optical signals including modulated signal portions at timings different from each other, optical fiber cables that respectively transmit the optical signals, a light synthesizer that synthesizes the optical signals to output a synthesized optical signal, a light amount detector that detects an output light amount of the synthesized optical signal, a modulated signal detector that detects the modulated signal portions from the detected output light amount, an image modulator that modulates the synthesized optical signal according to an input image signal to output a modulated image light, and a light source controller that outputs drive control signals for respectively outputting the optical signals respectively including the modulated signal portions according to the image signal, and detects a failure of the optical fiber cables based on whether a modulated signal portion among the plurality of modulated signal portions is detected.

A light source apparatus includes a first light source configured to emit first color light, a second light source configured to emit second color light having a different wavelength from that of the first color light, a wavelength conversion element configured to convert the first color light into third color light having a wavelength different from that of the first color light and to emit the third color light, and to emit the second color light as it is, and an optical system including a light guide surface configured to guide the first color light from the first light source and the second color light from the second light source to the wavelength conversion element, and the optical system being configured to emit combined light of the second color light and the third color light from the wavelength conversion element.

A light source device includes a light source module, a plurality of heat receiving plates coupled to the light source module, and a cooling plate coupled to the plurality of heat receiving plates, cooling liquid flowing on the inside of the cooling plate. The cooling plate includes an upstream-side flowing section, a downstream-side flowing section, and a plurality of heat transfer sections provided in at least one of the upstream-side flowing section and the downstream-side flowing section and aligned in a second direction. The plurality of heat transfer sections include a plurality of fins extending in the second direction and a plurality of channels provided among the plurality of fins. The plurality of heat receiving plates are disposed along the second direction. The plurality of heat transfer sections are separated from one another in positions among the plurality of heat receiving plates in the second direction.