Abstract: A present disclosure relates to a projector including a light source, an excitation light source, a wavelength converter, a collimator system that parallelizes fluorescence outputted from the wavelength converter, a light separator that separates the fluorescence into second light and third light, a correction lens provided in an optical path of the second or third light, a superimposing lens, a light modulator having a plurality of pixels each including first, second, and third sub-pixels, a microlens array including a plurality of microlenses corresponding to the plurality of pixels, and a projection optical apparatus. First light is incident on a first position on the superimposing lens, the second light is incident on a second position on the superimposing lens, and the third light is incident on a third position on the superimposing lens.

Abstract: An illuminator includes a first laser light source section that outputs a first light flux that belongs to a first wavelength band, a second laser light source section that outputs a second light flux that belongs to a second wavelength band, a third laser light source section that outputs a third light flux that belongs to a third wavelength band and has a polarization direction different from those of the first and second light fluxes, a light combiner that combines the first, second, and third light fluxes to produce combined light, and a predetermined band retardation film on the downstream of the light combiner that changes the phase of a light flux that forms the combined light and belongs to the third wavelength band, and the polarization directions of the light fluxes contained in the combined light are aligned on the downstream of the predetermined band retardation film.

Abstract: An optical semiconductor device includes a semiconductor substrate, a first semiconductor layer provided on the semiconductor substrate, and a mesa waveguide provided on the principal surface of the first semiconductor layer. The semiconductor device also includes a buried layer covering the upper surface of the first semiconductor layer. Part of the upper surface of the first semiconductor layer is exposed. A mesa structure provided at the boundary between a part of the first semiconductor layer is covered with the buried layer and a part of the first semiconductor layer is exposed. One side of the mesa structure is covered with the buried layer, and the other side is exposed. The optical semiconductor device can reduce the generation of stress in the buried layer, for example, to suppress the occurrence of cracks in the buried layer and enhance the reliability.

Abstract: It is an object of the present invention to provide a technique for making it possible to reduce the size of a Mach-Zehnder type optical modulator. In a clad layer, provided are a plurality of first and second via holes along an optical waveguide. The Mach-Zehnder type optical modulator includes a first travelling wave electrode connected to a first semiconductor region through the plurality of first via holes, extending along the optical waveguide in a plan view to have a width which is wider and a length and a second travelling wave electrode connected to a second semiconductor region through the plurality of second via holes, extending along the optical waveguide in a plan view to have a width which is wider and a length.

Abstract: An illumination optical apparatus includes a light source apparatus that outputs light in a first direction along an illumination optical axis and a homogenizer. The light source apparatus includes first to fourth light exiting sections via which first to fourth color light fluxes exit. The homogenizer includes a first array set, a second array set, a third array set, a fourth array set, and a superimposing lens. The array sets each include a pair of lens arrays, and at least one of the array sets inclines with respect to an imaginary plane perpendicular to the illumination optical axis in such a way that a first area is shifted in the first direction from a second area the distance from which to the illumination optical axis is longer than the distance from the first area to the illumination optical axis.

Abstract: A light source device configured to emit a light beam in a first direction includes a first exit position from which a first colored light beam is emitted, a second exit position from which a second colored light beam is emitted, a third exit position from which a third colored light beam is emitted, and a fourth exit position from which a fourth colored light beam is emitted, at least one of the first through fourth colored light beams is a target colored light beam which has a peak wavelength out of a reference wavelength range, and a beam diameter of which is to be adjusted, an adjusting element disposed on a light path of the target colored light beam.

Abstract: A light source apparatus according to an aspect of the present disclosure includes a light emitter that outputs light, a multi-lens array having a first surface on which the light outputted from the light emitter is incident and a second surface via which the light incident via the first surface exits, a light transmissive member having a third surface on which the light that exits via the second surface is incident and a fourth surface via which the light incident via the third surface exits, and a seal member that seals the space between the second surface and the third surface, and the multi-lens array forms a focal point which is located on the light exiting side with respect to the first surface and where the light that enters the multi-lens array is focused.

Abstract: A light source apparatus according to the present disclosure includes a light source section, a first polarization separator that transmits in a first polarization component of the first light and reflects a second polarization component of the first light, a second polarization separator that reflects the first polarization component, a diffuser that diffuses the second polarization component and causes the diffused second polarization component, a first wavelength converter that converts the wavelength of the first polarization component into second light, and a second wavelength converter that is disposed in a position shifted in a fifth direction from a placement plane where the first polarization separator and the second polarization separator are placed, converts the wavelength of the excitation light into third light, and the second polarization separator transmits the first polarization component of the second light and reflects the second polarization component of the second light.

Abstract: A light source apparatus according to an aspect of the present disclosure includes a light source section, a first polarization separator that transmits a first polarization component of first light and reflects a second polarization component of the first light, a second polarization separator that reflects the first polarization component, transmits a third polarization component of second light, and reflects a fourth polarization component of the second light, a diffuser that diffuses the second polarization component and causes the diffused second polarization component, a wavelength converter that converts the wavelength of the first polarization component and causes the second light, and a first phase retarder that is provided in the optical path of the first light between the first polarization separator and the second polarization separator and converts the first polarization component of the first light into the second polarization component.

Abstract: A light source apparatus according to an aspect of the present disclosure includes a light source section, a first polarization separator that transmits a first polarization component of first light and reflects a second polarization component of the first light, a second polarization separator that reflects the first polarization component, transmits a third polarization component of second light, and reflects a fourth polarization component of the second light, a diffuser that diffuses the second polarization component and causes the diffused second polarization component, and a wavelength converter that converts the wavelength of the first polarization component and causes the second light. The first polarization separator includes a first polarization separation layer and first bases. The second polarization separator includes a second polarization separation layer and second bases. At least one of the first bases and the second bases is made of quartz.

Abstract: A projector includes a first light source, a first light modulator on which first light is incident, a first polarization separator disposed on a first optical path along which the first light emitted from the first light source and entering the first light modulator travels, a first retardation film disposed on the first optical path, a first reflector disposed on the first optical path, and a second light modulator on which second light different from the first light is incident. The first optical path passes through the first polarization separator and the first retardation film, is then deflected back by the first reflector, and reaches the first light modulator via the first retardation film and the first polarization separator. A second optical path along which the second light travels is independent of the first optical path and does not intersect the first optical path.

Abstract: A light source device according to the present disclosure includes a light source section for emitting a first pencil and a second pencil which have a first wavelength band, a first optical element for altering a proceeding direction of a principal ray of the first pencil, a second optical element for altering a proceeding direction of a principal ray of the second pencil, and a wavelength conversion layer having a plane of incidence which the first pencil and the second pencil enter, and for performing wavelength conversion of the first pencil and the second pencil into fluorescence having a second wavelength band. The first optical element and the second optical element alter the proceeding directions of the principal ray of the first pencil and the principal ray of the second pencil so that the first pencil and the second pencil fail to overlap each other on the plane of incidence.

Abstract: A light source device according to the present disclosure includes a light source section for emitting a first pencil and a second pencil, a first optical element for altering a proceeding direction of a principal ray of the first pencil, a second optical element for altering a proceeding direction of a principal ray of the second pencil, a wavelength conversion layer having a plane of incidence, a reflecting surface, a first side surface, and a second side surface, a first reflecting element having a first reflecting surface, and a second reflecting element having a second reflecting surface.

Abstract: A projector includes a first light source device configured to emit first light having a first wavelength band, a second light source device configured to emit second light having a second wavelength band, a first light modulator configured to modulate the first light, and a second light modulator configured to modulate the second light. The first light source device includes a first light emitting element configured to emit excitation light and a wavelength converter configured to convert the excitation light into the first light. The second light source device includes a second light emitting element configured to emit the second light, a diffuser configured to diffuse the second light, and an optical element having an aspherical surface. The optical element is disposed on an optical path of the second light between the diffuser and the second light modulator and is configured to increase field curvature on the second light modulator.

Abstract: A light source device configured to emit a light beam in a first direction emits a first colored light beam from a first exit position, a second colored light beam longer in wavelength than the first colored light beam, a third colored light beam shorter in wavelength than the first colored light beam, and a fourth colored light beam, a mixed light beam including the first colored light beam and the second colored light beam enters an outgoing light switching device disposed in a light path of the fourth colored light beam.

Abstract: An optical waveguide interferometer that includes a first optical section, a second optical section, and a set of optical waveguides configured to connect the first and second optical sections, such that light propagating between the first optical section and the second optical section passes through each optical waveguide in the set, wherein the set of optical waveguides includes a first optical waveguide having a first length and a first width and a second optical waveguide having a second length and a second width, wherein the second length is greater than the first length, and the second width is greater than the first width.

Abstract: The object is to provide a technology capable of efficiently injecting a current into a core layer of a buried waveguide. On one end side of the substrate, a buried waveguide including a core layer, a cladding layer, and a current blocking layer is disposed, both sides of the core layer in a layer-stacking direction are sandwiched by the cladding layer, and both sides of the core layer in a width direction that is perpendicular to the layer-stacking direction are sandwiched by the current blocking layer. On another end side of the substrate, a ridge waveguide including the core layer and the cladding layer is disposed, and both sides of the core layer in the layer-stacking direction are sandwiched by the cladding layer.

Abstract: A multi-mode interference multiplexer/demultiplexer can suppress reflected return light while guiding light to a single-mode waveguide. The multi-mode interference multiplexer/demultiplexer includes a multi-mode waveguide, a first single-mode waveguide connected to a first end, a second single-mode waveguide opposing the first single-mode waveguide, a third single-mode waveguide connected to a second end, a reflecting surface opposing the third single-mode waveguide, and a fourth single-mode waveguide connected to a side end. Light entering from the second or third single-mode waveguide is reflected off the reflecting surface and forms an image at a first connection on a side end of the fourth single-mode waveguide.

Abstract: The light source device of the invention includes an excitation light source that outputs an excitation light, a collecting system that collects the excitation light source, a first light-transmissive member that transmits the excitation light output from the collecting system, and a wavelength conversion layer having a first light incident surface crossing a traveling direction of the excitation light, a light exiting surface opposed to the first light incident surface, and a second light incident surface coupling an end portion of the first light incident surface and an end portion of the light exiting surface, wherein a focal point of the collecting system is formed inside of the wavelength conversion layer, and the wavelength conversion layer wavelength-converts the excitation light entering from the first light incident surface and the second light incident surface and generates a fluorescent light.

Abstract: The invention provides a light source device that may suppress decrease of wavelength conversion efficiency by reducing optical density of excitation light in a light incident surface of a wavelength conversion layer, and provides a projector including the light source device.