A lighting system with color temperature adjustment function is provided, which includes a lighting device and a mobile temperature signal transmitting device. The lighting device includes a color temperature control module, a wireless signal receiving module and a plurality of light sources having different color temperatures. The mobile temperature signal transmitting device includes a wireless signal transmitting module and a temperature detecting module. The temperature detecting module detects an environmental temperature and transmits a temperature signal to the wireless signal receiving module via the wireless signal transmitting module for the color temperature control module to control the light sources. Thus, the color temperature of the lighting device can be related to the environmental temperature.

A lighting system with color temperature adjustment function is provided, which includes a lighting device and a mobile temperature signal transmitting device. The lighting device includes a color temperature control module, a wireless signal receiving module and a plurality of light sources having different color temperatures. The mobile temperature signal transmitting device includes a wireless signal transmitting module and a temperature detecting module. The temperature detecting module detects an environmental temperature and transmits a temperature signal to the wireless signal receiving module via the wireless signal transmitting module for the color temperature control module to control the light sources. Thus, the color temperature of the lighting device can be related to the environmental temperature.

A Light Emitting Diode, LED, based lighting device arranged for emitting a particular color of light, wherein said LED based lighting device comprises a power supply unit arranged for providing a Direct Current, DC, bus voltage for powering LEDs, a plurality of parallel cascaded LED channels, wherein each of said LED channels is connected to said bus voltage and comprises at least one colored LED and a switch for activating said corresponding LED channel, a controller arranged for providing control signals to each of said switches in said LED channels for periodically activating said LED channels, wherein each of said control signals has a duty cycle, and wherein said controller is arranged for determining said duty cycles of said control signals based on a received color set point, wherein said controller is further arranged for determining an amount of deficiency in light output of each of said LED channels caused by parasitic effects in said LED based lighting device, by determining instantaneous currents of each channel and comparing said instantaneous currents with expected currents resulting from the determined duty cycles, and for increasing said duty cycles based on said determined amount of deficiency.

A Light Emitting Diode, LED, based lighting device arranged for emitting a particular color of light, wherein said LED based lighting device comprises a power supply unit arranged for providing a Direct Current, DC, bus voltage for powering LEDs, a plurality of parallel cascaded LED channels, wherein each of said LED channels is connected to said bus voltage and comprises at least one colored LED and a switch for activating said corresponding LED channel, a controller arranged for providing control signals to each of said switches in said LED channels for periodically activating said LED channels, wherein each of said control signals has a duty cycle, and wherein said controller is arranged for determining said duty cycles of said control signals based on a received color set point, wherein said controller is further arranged for determining an amount of deficiency in light output of each of said LED channels caused by parasitic effects in said LED based lighting device, by determining instantaneous currents of each channel and comparing said instantaneous currents with expected currents resulting from the determined duty cycles, and for increasing said duty cycles based on said determined amount of deficiency.

A multi-color temperature and multi-channel EMC bracket structure comprises a metal substrate with more than three pads arranged on a periphery thereof as multi-block electrodes. A cup-shaped insulating resin dam is located on the metal substrate. Part of the pad is located inside the insulating resin dam and another part of the pad is located outside the insulating resin dam. At least one white resin partition is arranged inside the insulating resin dam to divide the metal substrate into multiple areas for arranging different LED chip circuits respectively. The LED chip circuit comprising a plurality of LED chips. The spaces inside the cup-shaped insulating resin dam with respective to different LED chip circuits are encapsulated by fluorescent layers respectively, and the fluorescent layer is located on the LED chip. The present invention can be controlled in regions to achieve the effect of different color temperature.

A multi-color temperature and multi-channel EMC bracket structure comprises a metal substrate with more than three pads arranged on a periphery thereof as multi-block electrodes. A cup-shaped insulating resin dam is located on the metal substrate. Part of the pad is located inside the insulating resin dam and another part of the pad is located outside the insulating resin dam. At least one white resin partition is arranged inside the insulating resin dam to divide the metal substrate into multiple areas for arranging different LED chip circuits respectively. The LED chip circuit comprising a plurality of LED chips. The spaces inside the cup-shaped insulating resin dam with respective to different LED chip circuits are encapsulated by fluorescent layers respectively, and the fluorescent layer is located on the LED chip. The present invention can be controlled in regions to achieve the effect of different color temperature.

Systems for apparatuses formed of light emitting devices. Solutions for controlling the off-state appearance of lighting system designs is disclosed. Thermochromic materials are selected in accordance with a desired off-state of an LED device. The thermochromic materials are applied to a structure that is in a light path of light emitted by the LED device. In the off-state the LED device produces a desired off-state colored appearance. When the LED device is in the on-state, the thermochromic materials heat up and become more and more transparent. The light emitted from the device in its on-state does not suffer from color shifting due to the presence of the thermochromic materials. Furthermore, light emitted from the LED device in its on-state does not suffer from attenuation due to the presence of the thermochromic materials. Techniques to select and position thermochromic materials in or around LED apparatuses are presented.

Systems for apparatuses formed of light emitting devices. Solutions for controlling the off-state appearance of lighting system designs is disclosed. Thermochromic materials are selected in accordance with a desired off-state of an LED device. The thermochromic materials are applied to a structure that is in a light path of light emitted by the LED device. In the off-state the LED device produces a desired off-state colored appearance. When the LED device is in the on-state, the thermochromic materials heat up and become more and more transparent. The light emitted from the device in its on-state does not suffer from color shifting due to the presence of the thermochromic materials. Furthermore, light emitted from the LED device in its on-state does not suffer from attenuation due to the presence of the thermochromic materials. Techniques to select and position thermochromic materials in or around LED apparatuses are presented.

The invention relates to a method for controlling a current to a light-emitting diode in order for it to emit a desired light flux, wherein the current is determined depending on a time period during which the light-emitting diode is supplied with current, in order to generate the desired light flux for said light-emitting diode.

The invention relates to a method for controlling a current to a light-emitting diode in order for it to emit a desired light flux, wherein the current is determined depending on a time period during which the light-emitting diode is supplied with current, in order to generate the desired light flux for said light-emitting diode.