Abstract: A colloidal crystal structure includes a colloidal crystal layer including a plurality of colloidal particles and a binder disposed between the plurality of colloidal particles to fix the colloidal particles, and a refractive index control material that is provided on one surface of the colloidal structural layer, is transparent, and has a refractive index difference of less than 10% with respect to the binder. A light-emitting device includes an optical filter including the colloidal crystal structure, and a light source, and a part of primary light emitted by the light source passes through the optical filter. A lighting system includes the light-emitting device.

Abstract: A colloidal crystal structure includes a colloidal crystal layer including a plurality of colloidal particles and a binder disposed between the plurality of colloidal particles to fix the colloidal particles, and a refractive index control material that is provided on one surface of the colloidal structural layer, is transparent, and has a refractive index difference of less than 10% with respect to the binder. A light-emitting device includes an optical filter including the colloidal crystal structure, and a light source, and a part of primary light emitted by the light source passes through the optical filter. A lighting system includes the light-emitting device.

Abstract: A lighting device which outputs output light includes: a light source; and an optical member which includes at least one of reflection wavelength selectivity or transmission wavelength selectivity depending on an incidence angle ? of incident light from the light source, wherein the incident light is incident on the optical member at a plurality of different incidence angles ?, the incident light is converted into outgoing light through the optical member, the outgoing light includes reflected light reflected by the optical member and transmitted light transmitted through the optical member, the output light is light based on the outgoing light, and chromaticity of the output light continuously changes on a surface irradiated by the output light.

Abstract: An illumination apparatus that is to be disposed in a recess formed in a part of a building includes: a light-emitting module that includes a board and a plurality of light-emitting elements disposed on the board; a light diffuser that has translucency and covers the light-emitting module; and a specular reflector that is disposed between the light-emitting module and the light diffuser. The light-emitting module emits light toward the light diffuser, and the specular reflector reflects light from the light diffuser.

Abstract: A rotation speed calculation device of a brushless motor includes: a current acquisition unit that acquires magnitude of current flowing through a coil of the brushless motor; a supply voltage acquisition unit that acquires supply voltage supplied to the brushless motor; and a calculation unit that calculates rotation speed of the brushless motor based on the magnitude of the current acquired by the current acquisition unit, the supply voltage acquired by the supply voltage acquisition unit, and a voltage equation calculating the rotation speed based on the magnitude of the current and the supply voltage. The voltage equation is an equation in which a member expressing a voltage drop due to inductance of a winding of the coil of the brushless motor is expressed by a product of a factor proportional to the current and a factor proportional to the rotation speed of the brushless motor.

Abstract: An illumination system includes: a first luminaire that emits first illumination light having a color simulating a sky; a second luminaire that is disposed in a same space as the first luminaire, the second luminaire projecting, on an object, second illumination light simulating sunlight to create a sunny portion on the object; and a controller that causes the first luminaire to emit the first illumination light according to an environment reproduction condition.

Abstract: An illumination apparatus that is to be disposed in a recess formed in a part of a building includes: a light-emitting module that includes a board and a plurality of light-emitting elements disposed on the board; a light diffuser that has translucency and covers the light-emitting module; and a light reflector that includes a wall having light-reflecting properties and surrounding the plurality of light-emitting elements. Among the plurality of light-emitting elements, every two adjacent light-emitting elements are disposed on the board at a first interval. Among the plurality of light-emitting elements, a light-emitting element closest to the wall is disposed on the board with a second interval to the wall, the second interval being larger than ¼ of the first interval and smaller than the first interval.

Abstract: An illumination apparatus includes: a case having an opening portion; a first light source disposed in the case and including a plurality of light-emitting elements; a light diffuser which is disposed in the opening portion, diffuses and transmits light emitted from the first light source, and from which the diffused light and the transmitted light exit; a light emission component disposed outside a light exit region of the light diffuser on a light exit surface side of the light diffuser; and a second light source that emits light to the light emission component to cause the light emission component to radiate light.

Abstract: An illumination apparatus includes: a case having an opening portion; a light source disposed in the case and including a plurality of light-emitting elements; a light diffuser which is disposed in the opening portion, and diffuses and transmits light emitted from the plurality of light-emitting elements; and a controller that controls light emission from the light source. The controller: controls light emission from the plurality of light-emitting elements to project an image on the light diffuser, the image changing with time; and when changing the light emission from the plurality of light-emitting elements changing the image, controls the light emission from the light source to keep a change in at least one of (i) a light amount, (ii) a color temperature, and (iii) a spectral distribution of light emitted from the illumination apparatus within a predetermined range.

Abstract: A lighting apparatus includes: a light source; a light-transmissive diffuser panel disposed to receive light emitted from the light source; a frame having an opening through which light passes; and a light blocker that blocks the light emitted from the light source. The diffuser panel is fixed to the frame to cover the opening. The light blocker blocks a portion of the light passing through the opening.

Abstract: A rotation speed calculation device of a brushless motor includes: a current acquisition unit that acquires magnitude of current flowing through a coil of the brushless motor; a supply voltage acquisition unit that acquires supply voltage supplied to the brushless motor; and a calculation unit that calculates rotation speed of the brushless motor based on the magnitude of the current acquired by the current acquisition unit, the supply voltage acquired by the supply voltage acquisition unit, and a voltage equation calculating the rotation speed based on the magnitude of the current and the supply voltage. The voltage equation is an equation in which a member expressing a voltage drop due to inductance of a winding of the coil of the brushless motor is expressed by a product of a factor proportional to the current and a factor proportional to the rotation speed of the brushless motor.

Abstract: A lighting apparatus includes: a light source; a light-transmissive diffuser panel disposed to receive light emitted from the light source; a frame having an opening through which light passes; and a light blocker that blocks the light emitted from the light source. The diffuser panel is fixed to the frame to cover the opening. The light blocker blocks a portion of the light passing through the opening.

Abstract: An illumination apparatus includes: a case having an opening portion; a first light source disposed in the case and including a plurality of light-emitting elements; a light diffuser which is disposed in the opening portion, diffuses and transmits light emitted from the first light source, and from which the diffused light and the transmitted light exit; a light emission component disposed outside a light exit region of the light diffuser on a light exit surface side of the light diffuser; and a second light source that emits light to the light emission component to cause the light emission component to radiate light.

Abstract: An illumination apparatus that is to be disposed in a recess formed in a part of a building includes: a light-emitting module that includes a board and a plurality of light-emitting elements disposed on the board; a light diffuser that has translucency and covers the light-emitting module; and a light reflector that includes a wall having light-reflecting properties and surrounding the plurality of light-emitting elements. Among the plurality of light-emitting elements, every two adjacent light-emitting elements are disposed on the board at a first interval. Among the plurality of light-emitting elements, a light-emitting element closest to the wall is disposed on the board with a second interval to the wall, the second interval being larger than ¼ of the first interval and smaller than the first interval.

Abstract: An illumination system includes: a first luminaire that emits first illumination light having a color simulating a sky; a second luminaire that is disposed in a same space as the first luminaire, the second luminaire projecting, on an object, second illumination light simulating sunlight to create a sunny portion on the object; and a controller that causes the first luminaire to emit the first illumination light according to an environment reproduction condition.

Abstract: An illumination system includes: a first luminaire that is of an internal lighting type and includes a light emitter that emits first illumination light having a color simulating a sky; and a second luminaire that is of a projection type and includes a projector that projects, on an object, second illumination light having a color simulating sunlight. The first luminaire and the second luminaire are disposed in a same space, and the first luminaire is disposed higher with respect to a floor than a projection area created on the object by the second illumination light.

Abstract: An illumination apparatus includes: a case having an opening portion; a light source disposed in the case and including a plurality of light-emitting elements; a light diffuser which is disposed in the opening portion, and diffuses and transmits light emitted from the plurality of light-emitting elements; and a controller that controls light emission from the light source. The controller: controls light emission from the plurality of light-emitting elements to project an image on the light diffuser, the image changing with time; and when changing the light emission from the plurality of light-emitting elements changing the image, controls the light emission from the light source to keep a change in at least one of (i) a light amount, (ii) a color temperature, and (iii) a spectral distribution of light emitted from the illumination apparatus within a predetermined range.

Abstract: An illumination apparatus that is to be disposed in a recess formed in a part of a building includes: a light-emitting module that includes a board and a plurality of light-emitting elements disposed on the board; a light diffuser that has translucency and covers the light-emitting module; and a specular reflector that is disposed between the light-emitting module and the light diffuser. The light-emitting module emits light toward the light diffuser, and the specular reflector reflects light from the light diffuser.

Abstract: The rotation period of a motor is subdivided by edge interval times and a rate of change between a currently calculated edge interval time and an edge interval time calculated one rotation of the motor previously is calculated at the detection of each edge. Then the rotation period of the motor is calculated by multiplying a set reference period by the calculated rate of change.

Abstract: The rotation period of a motor is subdivided by edge interval times and a rate of change between a currently calculated edge interval time and an edge interval time calculated one rotation of the motor previously is calculated at the detection of each edge. Then the rotation period of the motor is calculated by multiplying a set reference period by the calculated rate of change.