Abstract: An optical scanning device includes: a first waveguide that propagates light by total reflection; and a second waveguide. The second waveguide includes: a first multilayer reflective film; a second multilayer reflective film that faces the first multilayer reflective film; and a first optical waveguide layer directly connected to the first waveguide and located between the first and second multilayer reflective films. The first optical waveguide layer has a variable thickness and/or a variable refractive index and propagates the light transmitted through the first waveguide. The first multilayer reflective film has a higher light transmittance than the second multilayer reflective film and allows part of the light propagating through the first optical waveguide layer to be emitted to the outside. By changing the thickness of the first optical waveguide layer and/or its refractive index, the direction of the part of the light emitted from the second waveguide is changed.

Abstract: An optical device includes a first waveguide that propagates light in a first direction; and a second waveguide including a first mirror, a second mirror, and an optical waveguide layer. The first mirror extends in the first direction and has a first reflecting surface, and the second mirror extends in the first direction and has a second reflecting surface. The optical waveguide layer is located between the first and second mirrors and propagates the light in the first direction. A forward end portion of the first waveguide is disposed inside the optical waveguide layer. In a region in which the first and second waveguides overlap each other when viewed in a direction perpendicular to the first reflecting surface, at least part of the first waveguide and/or at least part of the second waveguide includes at least one grating whose refractive index varies periodically in the first direction.

Abstract: An optical device includes a first mirror having a first reflecting surface and extending along a first direction, a second mirror having a second reflecting surface that faces the first reflecting surface and extending along the first direction, and an optical waveguide layer, located between the first mirror and the second mirror, that causes light to propagate along the first direction. A transmittance of the first mirror is higher than a transmittance of the second mirror. A reflection spectrum of at least either the first mirror or the second mirror with respect to light arriving from a direction normal to the reflecting surface includes, in a wavelength region in which a reflectance is higher than or equal to 90%, a local maximum point and first and second points of inflection located closer to a long-wavelength side than the local maximum point.

Abstract: An optical device includes a first substrate having a first surface, a second substrate having a second surface, at least one optical waveguide, and a plurality of spacers, disposed on at least either the first surface or the second surface, that include a first portion and a second portion. The first portion of the plurality of elastic spacers is at least one elastic spacer located in a region between the first substrate and the second substrate in which the first substrate and the second substrate overlap each other as seen from an angle parallel with a direction perpendicular to the first surface. The second portion of the plurality of elastic spacers is at least one elastic spacer located in a region in which the first substrate and the second substrate do not overlap each other as seen from an angle parallel with the direction perpendicular to the first surface.

Abstract: An optical device includes a first waveguide extending in a first direction and a second waveguide connected to the first waveguide. The second waveguide includes a first mirror, a second mirror, and an optical waveguide layer. At least either the first waveguide or the second waveguide has one or more gratings in a part of a connection region in which the first mirror, the second mirror, and the first waveguide overlap one another when seen from an angle parallel with a direction perpendicular to a first reflecting surface of the first mirror. The one or more gratings is at a distance that is longer than at least either a thickness of the first mirror or a thickness of the second mirror in the first direction from an end of the first mirror or the second mirror that is in the connection region.

Abstract: An optical device includes a nanostructure body which induces surface plasmon resonance when irradiated with light, an alloy layer which is in contact with the nanostructure body and which has a lower work function than the nanostructure body, and an n-type semiconductor which is in Schottky contact with the alloy layer. The nanostructure body is composed of one selected from the group consisting of elemental metals, alloys, metal nitrides, and conductive oxides. The alloy layer is composed of at least two metals.

Abstract: An optical device includes a nanostructure body which induces surface plasmon resonance when irradiated with light, an oxide layer which is in contact with the nanostructure body, an alloy layer which is in contact with the oxide layer and which is made of an alloy containing a first metal and a second metal that are different in work function from each other, and an n-type semiconductor which is in Schottky contact with the alloy layer.

Abstract: An optical filter array is used in a photodetection device that generates image data separately for each of N (where N is an integer greater than or equal to 4) wavelength bands. The optical filter array includes a plurality of optical filters. The plurality of optical filters include plural types of optical filters differing in transmittance from each other in each of the N wavelength bands. Assuming that pi is an average of transmittances of the plurality of optical filters for light in an ith wavelength band (where i is an integer greater than or equal to 1 and less than or equal to N) of the N wavelength bands, a standard deviation of the average ?i of the transmittances for the N wavelength bands is less than or equal to 0.13.

Abstract: An optical device includes: a first mirror having translucency and including a first reflecting surface extending along a first direction and a second direction intersecting the first direction; a second mirror including a second reflecting surface facing the first reflecting surface; an optical waveguide layer located between the first mirror and the second mirror, the optical waveguide layer including a plurality of non-waveguide areas laid side-by-side along the second direction and one or more optical waveguide areas located between the plurality of non-waveguide areas, the optical waveguide areas containing a liquid crystal material, having a higher average refractive index than do the plurality of non-waveguide areas, and propagating light along the first direction; and two electrode layers facing each other across the optical waveguide layer, at least one of the two electrode layers including a plurality of electrodes laid side-by-side along the second direction.

Abstract: A photodetection device includes: a filter array including a plurality of filters arranged in a two-dimensional array, the plurality of filters including a first filter and a second filter, the first filter and the second filter each including a first reflective layer, a second reflective layer, and an intermediate layer between the first reflective layer and the second reflective layer and having a resonant structure having a plurality of resonant modes differing in order from each other, at least one selected from the group consisting of a refractive index and a thickness of the intermediate layer of the first filter being different from the at least one selected from the group consisting of a refractive index and a thickness of the intermediate layer of the second filter; and an image sensor disposed at a position where the image senor receives light having passed through the filter array.

Abstract: A fiber light source includes a solid-state light source, a wavelength convertor, and an optical fiber. The solid-state light source is configured to emit first light, the first light including blue light with a peak wavelength in a range of 430 to 470 nm, inclusive, and green light with a peak wavelength in a range of 480 to 550 nm, inclusive. The wavelength convertor is disposed on the light output side or the light incident side of the optical fiber and contains a red phosphor. The red phosphor includes Ce as a luminescent center, and is excited by at least part of the green light to emit second light. The second light has a spectrum with a peak wavelength in a range of 600 to 700 nm, inclusive. The red phosphor contains a nitride or an oxynitride as a host material.

Abstract: An optical filter includes a filter array including filters two-dimensionally arrayed and a band-pass filter. The filters includes first and second filters. A transmission spectrum of each of the first and second filters has local maximum values of transmittance at three or more wavelengths included in a first wavelength region. The band-pass filter passes light in a second wavelength region including two or more wavelengths of the three or more wavelengths and not including one or more wavelengths of the three or more wavelengths. The filter array and the band-pass filter are disposed so that (a) the band-pass filter is located on an optical path of light that passes through the first and second filters or (b) the first and second filters are located on an optical path of light that passes through the band-pass filter.

Abstract: A light detecting device includes: a filter array including filters two-dimensionally arrayed and an image sensor including light detection elements. Each of first and second filters included in the filters includes a first reflective layer, a second reflective layer, and an intermediate layer therebetween and has a resonance structure having resonant modes whose orders are different from each other. A refractive index and/or a thickness of the intermediate layer in the first and second filters is different depending on the filter. A transmission spectrum of each of the first and second filters has local maximum value of transmittance at each of wavelengths included in a wavelength region, and the wavelengths correspond to the resonant modes, respectively. The image sensor is disposed at a position where the image senor receives passing light that passes through the filter array, to detect components in the wavelengths included in the passing light.

Abstract: An optical device includes: a waveguide array including a plurality of waveguides; and a pulse generator. The waveguides are arranged in a first direction and extend in a second direction intersecting the first direction. The pulse generator inputs, as an input light beam, a light pulse of light to each of the waveguides. The light has a frequency spectrum in air with a maximum peak at a frequency corresponding to a wavelength ?, and the full width at half maximum of the maximum peak is ??. The waveguides propagate the input light beams in the second direction and emit part of the input light beams as emission light. The pulse generator adjusts the difference in phase between input light beams to be inputted to two adjacent waveguides of the plurality of waveguides to thereby change a first direction component of an emission direction of the emission light.

Abstract: A projector includes a light source unit, a spatial light modulator configured to control light from the light source unit for each pixel to form an optical image, and a projection optical system configured to project the optical image formed by the spatial light modulator onto a target. The light source unit includes a solid-state light source and a wavelength convertor. The solid-state light source is configured to emit first light, the first light including blue light with a peak wavelength in a range of 430 to 470 nm, inclusive, and green light with a peak wavelength in a range of 480 to 550 nm, inclusive. The wavelength convertor contains a red phosphor including Ce as a luminescent center that is configured to emit second light upon receiving the green light. The second light has a spectrum with a peak wavelength of 600 to 700 nm, inclusive. The red phosphor contains a nitride or an oxynitride as a host material.

Abstract: A range-information acquiring apparatus includes a light source, an image sensor, a control circuit, and a signal processing circuit. The control circuit causes the light source to emit first light toward a scene and subsequently emit second light toward the scene, the first light having a first spatial distribution, the second light having a second spatial distribution. The control circuit causes at least a portion of plural photodetector elements of the photodetector device to detect first reflected light and second reflected light in the same exposure period, the first reflected light being caused by reflection of the first light from the scene, the second reflected light being caused by reflection of the second light from the scene. The signal processing circuit generates range data based on photodetection data output from the photodetector elements of the photodetector device.

Abstract: An optical device includes a first mirror, a second mirror facing the first mirror, an optical waveguide layer, located between the first mirror and the second mirror, that contains a material whose refractive index changes when a voltage is applied, first and second electrodes directly or indirectly holding the optical waveguide layer therebetween, the first electrode including a plurality of electrode sections arranged in a first direction, and a control circuit. The light is emitted via the first mirror from the optical waveguide layer, or the light is taken into the optical waveguide layer via the first mirror.

Abstract: An optical device includes a first substrate, a second substrate, a plurality of separation walls, one or more optical waveguides, and one or more spacers. The first substrate has a surface which extends in a first direction and a second direction intersecting the first direction. The second substrate faces the first substrate. The plurality of separation walls are positioned between the first substrate and the second substrate and extend in the first direction. The one or more optical waveguides are positioned between the first substrate and the second substrate and include one or more dielectric members which are positioned between the plurality of separation walls and which extend in the first direction. The one or more spacers are directly or indirectly sandwiched between the first substrate and the second substrate and positioned around the one or more optical waveguides.

Abstract: An optical scan device includes an optical waveguide array, including a plurality of optical waveguides each of which propagates light along a first direction, that emits a light beam, the plurality of optical waveguides being arranged in a second direction that intersects the first direction, a phase shifter array including a plurality of phase shifters connected separately to each of the plurality of optical waveguides, a control circuit that controls a phase shift amount of each of the plurality of phase shifters and/or inputting of light to each of the plurality of phase shifters and thereby controls a direction and shape of the light beam that is emitted from the optical waveguide array, a photodetector that detects the light beam reflected by a physical object, and a signal processing circuit that generates distance distribution data on the basis of output from the photodetector.

Abstract: The phosphor according to an aspect of the present disclosure contains a crystal phase having a chemical composition CexYyLa3-x-ySi6N11, where x and y satisfy 0<x?0.6, and (1.5?x)?y?(3?x). The phosphor has an emission spectral peak within a wavelength range of 600 nm or more and 660 nm or less and a first excitation spectral peak within a wavelength range of 480 nm or more and 550 nm or less.