Abstract: A surface-emitting laser includes an active layer; multiple reflectors sandwiching the active layer; and an electrode pair connected to a power supply, through which a current is injected into the active layer. The surface-emitting laser emits at least one laser beam during a current injection period when the current injected into the active layer through the electrode pair during the current injection period is a first current and emits at least one laser beam during a current decrease period when the current injected into the active layer through the electrode pair during the current injection period is a second current exceeding the first current. The current decrease period is after the current injection period. The current injected into the active layer during the current decrease period is lower than the current injected into the active layer during the current injection period.

Abstract: Signal measurement units each measure a signal output from a sound source, as a measured signal. Reference signal acquisition units each acquire a reference signal. A weighting processing unit creates weighted reference signals by weighting the reference signals. A time synchronization correction calculation unit calculates a time synchronization correction value based on the weighted reference signals. The time synchronization correction value is a correction value for synchronizing the two measured signals. An arrival time difference calculation unit calculates an arrival time difference based on the time synchronization correction value. The arrival time difference is a difference between elapsed times for the two measured signals acquired by respective ones of the pair of signal measurement units to arrive at the respective ones of the pair of signal measurement units. A sound source position calculation unit calculates a position of the sound source based on the arrival time difference.

Abstract: Signal measurement units each measure a signal output from a sound source, as a measured signal. Reference signal acquisition units each acquire a reference signal. A weighting processing unit creates weighted reference signals by weighting the reference signals. A time synchronization correction calculation unit calculates a time synchronization correction value based on the weighted reference signals. The time synchronization correction value is a correction value for synchronizing the two measured signals. An arrival time difference calculation unit calculates an arrival time difference based on the time synchronization correction value. The arrival time difference is a difference between elapsed times for the two measured signals acquired by respective ones of the pair of signal measurement units to arrive at the respective ones of the pair of signal measurement units. A sound source position calculation unit calculates a position of the sound source based on the arrival time difference.

Abstract: A first light source that emits first light of a first wavelength band; an optical path separator that separates the first light into fourth light and fifth light having different optical paths from each other; and a first optical path combiner that combines the fourth light and the fifth light are included, where the fourth light includes light of a fourth wavelength band being a predetermined band in the first wavelength band and light having a polarization component in a first direction being a predetermined polarization direction in a fifth wavelength band being a band other than the fourth wavelength band in the first wavelength band, and the fifth light is light having a polarization component in a second direction orthogonal to the first direction in the fifth wavelength band.

Abstract: Green and red light from first green and red light sources light a first element. Green and red light from second green and red light sources light a second element. Blue light from a blue light source light a third element. A control unit causes an image of a first video signal to be displayed on the first element during lighting of first red source, and causes an image of a second video signal to be displayed on the first element during lighting of the first green source. The unit causes an image of the first signal to be displayed on the second element during lighting of the second red source, and causes an image of the second signal to be displayed on the second element during lighting of the second green source. The unit causes an image of a third video signal to be displayed on the third element.

Abstract: A first light source that emits first light of a first wavelength band; an optical path separator that separates the first light into third light and second light whose polarization directions are orthogonal to each other; an optical path separator and combiner that separates the second light into fourth light and fifth light having different wavelength bands from each other; a reflector that reflects the fifth light to a direction of the optical path separator and combiner; and an optical path combiner that combines the third light and the second light are included.

Abstract: [Problem] To collect emitted light while sufficiently improving light extraction efficiency of a light emitting element, and to make it easy for the emitted light to enter the optical system of a latter stage. [Solution] A light emitting element and a taper rod having the area of its emission plane larger than that of its incidence plane are provided, and a transparent resin is filled between the light emitting element and the taper rod. At least part of the taper rod has a refractive index higher than that of the transparent resin.

Abstract: An optical element that can reduce the etendue of emitted light emitted from the optical element without having depend on the etendue of light-emitting elements is provided with a plasmon-excitation layer that is interposed between two layers having dielectric properties wherein, taking the plasmon-excitation layer as a border, the effective dielectric constant of the emission-side portion that is the emission layer side is higher than the effective dielectric constant of the incident-side portion that is the side of a carrier-generating layer, and the dielectric constant between the plasmon-excitation layer and the carrier-generating layer is higher than the dielectric constant between the carrier-generating layer and the light-incident surface.

Abstract: Provided is an optical element that highly efficiently radiates light with high directivity at low etendue. The optical element includes a light emission layer (103) generating an exciton to emit light, a plasmon excitation layer (105) having a higher plasma frequency than a light emission frequency of the light emission layer (103), an output layer (107) converting light or a surface plasmon generated on an upper surface of the plasmon excitation layer (105) into light with a predetermined output angle to output the light, and a dielectric layer (102).

Abstract: A first light source that emits first light of a first wavelength band; an optical path separator that separates the first light into fourth light and fifth light having different optical paths from each other; and a first optical path combiner that combines the fourth light and the fifth light are included, where the fourth light includes light of a fourth wavelength band being a predetermined band in the first wavelength band and light having a polarization component in a first direction being a predetermined polarization direction in a fifth wavelength band being a band other than the fourth wavelength band in the first wavelength band, and the fifth light is light having a polarization component in a second direction orthogonal to the first direction in the fifth wavelength band.

Abstract: A light source unit includes a light emission unit, a wavelength conversion unit and a first wavelength selection, unit. The light emission unit has a light emission surface which emits light of a first wavelength band and reflects incident light. The wavelength conversion unit has an incidence/emission surface which, when light of the first, wavelength band is incident on it, emits light of a second wavelength band toward the same side as that of the incidence of the light, of the first wavelength band and reflects light of the second wavelength band re-incident on it. The first wavelength selection unit has a first reflection surface which reflects light, of the first wavelength band and transmits light of the second wavelength band. Light from the light emission surface, light, reflected by the first reflection surface, and light reflected by the light emission surface become incident on the incidence/emission surface.

Abstract: A first light source that emits first light of a first wavelength band; an optical path separator that separates the first light into third light and second light whose polarization directions are orthogonal to each other; an optical path separator and combiner that separates the second light into fourth light and fifth light having different wavelength bands from each other; a reflector that reflects the fifth light to a direction of the optical path separator and combiner; and an optical path combiner that combines the third light and the second light are included.

Abstract: Disclosed are an optical device, an optical element, and an image display device that can achieve an improved absorption efficiency of excitation light. The optical device includes: a light-emitting element; a carrier generation layer on which light from the light-emitting element is incident and in which carriers are generated; a plasmon excitation layer that excites a plasmon, stacked on the upper side of the carrier generation layer and has a plasma frequency higher than a frequency of light generated when the carrier generation layer is excited by the light from the light-emitting element; and an exit layer that converts light or a surface plasmon generated on a surface of the plasmon excitation layer into light having a predetermined exit angle and from which the light having the predetermined exit angle exits. The optical device further includes a polarization conversion layer on the lower side of the carrier generation layer.

Abstract: Provided are an optical element, a lighting device, and an image display device, with which the absorption efficiency and the luminance of the excitation light can be improved. This optical element (40) is equipped with: a light-emitting layer (103) that generates excitation light; a plasmon excitation layer (105) stacked on the light-emitting layer (103) and having a higher plasma frequency than the light-emitting frequency of the light-emitting layer (103); an emission layer (207) that emits light by converting the surface plasmons or the light generated at the upper surface of the plasmon excitation layer (105) to light having a predetermined emission angle; and a metal layer (102) stacked on the underside of the light-emitting layer (103).

Abstract: A light emitting device of the present invention comprises a light source and an optical filter and is characterized by that it further comprises a first light guiding member of a taper shape whose cross-sectional area is gradually increased and a second light guiding member whose flare angle is smaller than that of the taper shape of the first light guiding member, wherein the length of the second light guiding member is smaller than the first light guiding member.

Abstract: Provided is a polarizer that includes wire grid structure (11) having a plurality of thin metal wires arranged to extend in one direction. Thin metal wire (13) is formed by stacking aluminum layer (5) and silver layer (6). Silver layer 6 is disposed on a side wherein incoming light enters wire grid structure (11).

Abstract: Disclosed are an optical device, an optical element, and an image display device that can achieve an improved absorption efficiency of excitation light. The optical device includes: a light-emitting element; a carrier generation layer on which light from the light-emitting element is incident and in which carriers are generated; a plasmon excitation layer that excites a plasmon, stacked on the upper side of the carrier generation layer and has a plasma frequency higher than a frequency of light generated when the carrier generation layer is excited by the light from the light-emitting element; and an exit layer that converts light or a surface plasmon generated on a surface of the plasmon excitation layer into light having a predetermined exit angle and from which the light having the predetermined exit angle exits. The optical device further includes a polarization conversion layer on the lower side of the carrier generation layer.

Abstract: An optical element is provided with a plasmon excitation layer that facilitates both the control of plasmon resonant conditions and the improvement of conversion efficiency. The plasmon excitation layer that is provided in the optical element generates surface plasmons, and the plasmon excitation layer is made up of metal and a dielectric.

Abstract: An optical element that can reduce the etendue of emitted light emitted from the optical element without having depend on the etendue of light-emitting elements is provided with a plasmon-excitation layer that is interposed between two layers having dielectric properties wherein, taking the plasmon-excitation layer as a border, the effective dielectric constant of the emission-side portion that is the emission layer side is higher than the effective dielectric constant of the incident-side portion that is the side of a carrier-generating layer, and the dielectric constant between the plasmon-excitation layer and the carrier-generating layer is higher than the dielectric constant between the carrier-generating layer and the light-incident surface.

Abstract: Green light from solid-state light source 1G and red light from solid-state light source 1R are irradiated upon display element 5 by way of the same light path, green light from solid-state light source 2G and red light from solid-state light source 2R are irradiated upon display element 6 by way of the same light path, and blue light from solid-state light source 1B is irradiated upon display element 7. Control unit 10 lights solid-state light sources 1G and 1R in time division, causes an image based on first video signal S1 to be displayed on display element 5 during lighting of solid-state light source 1R, and causes an image based on second video signal S2 to be displayed on display element 5 during lighting of solid-state light source 1G.