Abstract: A lighting system includes a lighting fixture, a demand controller and a control board. The demand controller obtains power usage of a plurality of devices including the lighting fixture and, outputs a demand signal depending on the power usage obtained. The control board includes a switch provided on a power line and a switch controller that interrupts supply of power over the power line for a predetermined period of time by controlling the switch based on the output demand signal. The lighting fixture includes a light emitter, a detector, and a controller that causes the light emitter to emit light in a second dimming state darker than a first dimming state in which the light emitter emitted light immediately before the detection, if the detector detects that the supply of power has been interrupted for the predetermined period of time.

Abstract: A lighting device includes a first light source composed of first LEDs each configured to emit light with a first color temperature, a second light source composed of second LEDs each configured to emit light with a second color temperature lower than the first color temperature, a lighting circuit, and a control circuit. The number of second LEDs is less than that of the first LEDs. The lighting circuit is configured to cause the first and second light sources to light on by supplying first and second drive currents to the first and second light sources, respectively. The control circuit is configured to control lighting conditions of the first and second light sources so that: total light intensity of the first light source varies in response to a dimming signal; and total light intensity of the second light source is kept constant independently of the dimming signal.

Abstract: A lighting system includes a lighting fixture, a demand controller and a control board. The demand controller obtains power usage of a plurality of devices including the lighting fixture and, outputs a demand signal depending on the power usage obtained. The control board includes a switch provided on a power line and a switch controller that interrupts supply of power over the power line for a predetermined period of time by controlling the switch based on the output demand signal. The lighting fixture includes a light emitter, a detector, and a controller that causes the light emitter to emit light in a second dimming state darker than a first dimming state in which the light emitter emitted light immediately before the detection, if the detector detects that the supply of power has been interrupted for the predetermined period of time.

Abstract: A lighting device includes a first light source composed of first LEDs each configured to emit light with a first color temperature, a second light source composed of second LEDs each configured to emit light with a second color temperature lower than the first color temperature, a lighting circuit, and a control circuit. The number of second LEDs is less than that of the first LEDs. The lighting circuit is configured to cause the first and second light sources to light on by supplying first and second drive currents to the first and second light sources, respectively. The control circuit is configured to control lighting conditions of the first and second light sources so that: total light intensity of the first light source varies in response to a dimming signal; and total light intensity of the second light source is kept constant independently of the dimming signal.

Abstract: An illumination device is provided for controlling a color temperature of light irradiated from a light source having a plurality of light-emitting elements of different light colors. A control setting module provides a control signal associated with a desired color temperature for the irradiated light. A light quantity determination circuit determines light quantities for each of the light-emitting elements based on a relationship between the control signal from the control setting module and an inverse color temperature. A plurality of driver circuits provide driver signals to the light-emitting elements corresponding to the determined light quantities. In this manner the color temperature for light irradiated from the light source coincides with the desired color temperature.

Abstract: An illumination device is provided for controlling a color temperature of light irradiated from a light source having a plurality of light-emitting elements of different light colors. A control setting module provides a control signal associated with a desired color temperature for the irradiated light. A light quantity determination circuit determines light quantities for each of the light-emitting elements based on a relationship between the control signal from the control setting module and an inverse color temperature. A plurality of driver circuits provide driver signals to the light-emitting elements corresponding to the determined light quantities. In this manner the color temperature for light irradiated from the light source coincides with the desired color temperature.