Abstract:
The configuration of polychromatic sources of white light, which are composed of at least two groups of colored emitters, such as light-emitting diodes (LEDs), is disclosed. Based on a novel approach of the assessment of quality of white light using, for example, 1269 test color samples from the enhanced Munsell palette, the spectral compositions of light, such as white light, composed of two to five (or more) narrow-band emissions with the highest number of colors relevant to human vision rendered almost indistinguishably from a reference source, such as a blackbody radiator, are introduced. An embodiment of the current invention can be used, in particular, for configuring polychromatic sources of white light with the ultimate quality capable of rendering of all colors of the real world.
Abstract:
A method for mixing light of LEDs includes following steps: Firstly, a substrate with a red light LED, a green light LED and a blue light LED arranged thereon is provided. Secondly, a power source for supplying power to the red light LED, the green light LED and the blue light LED is provided. Thirdly, a temperature variation ΔT1 of the red light LED caused by the power source, a temperature variation ΔT2 of the green light LED caused by the power source, a temperature variation ΔT3 of the blue light LED caused by the power source are calculated. And finally, input currents applied to the red light LED, the green light LED and the blue light LED are adjusted according to the temperature variations ΔT1, ΔT2 and ΔT3. A lighting device using the method is also provided.
Abstract:
A system and method for the automatic color/brightness adjustment of a video display screen, panel, module or other display component comprising light emitting diodes (“LEDs”). The system and method incorporate a reference LED and a light sensor on each module and use decay information sensed from each reference LED to determine the amount of decay experienced by the display LEDs in the modules. Each module will be adjusted to have one uniform color/brightness level based on the decay information sensed from each reference LED.
Abstract:
Representative embodiments of the disclosure provide a system and apparatus for controlling an intensity and spectrum of light emitted from a solid state lighting system. The solid state lighting system has a first emitted spectrum at full intensity and at a selected temperature, with a first electrical biasing for the solid state lighting system producing a first wavelength shift, and a second electrical biasing for the solid state lighting system producing a second, opposing wavelength shift. Representative embodiments provide for receiving information designating a selected intensity level and a selected temperature and providing a combined first electrical biasing and second electrical biasing to the solid state lighting system to generate emitted light having the selected intensity level and having a second emitted spectrum within a predetermined variance of the first emitted spectrum over a predetermined range of temperatures.
Abstract:
In various embodiments, a method for calibrating a lighting device is provided. The lighting device may include at least one semiconductor light source. The method may include: determining a thermal power loss of the at least one semiconductor light source; determining an electrical power of the at least one semiconductor light source; and determining a light power of the at least one semiconductor light source from the electrical power and the thermal power loss.
Abstract:
An improved control circuit arrangement and control method is described for supplying power to, and for controlling, light-emitting diodes used for illuminating. The control circuit arrangement includes a driver circuit capable of operating in multiple modes for providing an operating current for operating at least one light-emitting diode, wherein the operating current has different positive intensities. In particular, the present control circuit arrangement and control method now deliberately exploit the fact that the color spectrum of a light emitting diode is dependent on the intensity or current with which it is operated, and improves the color rendering index by deliberately operating the light emitting diodes with different intensities over time.
Abstract:
A multi-die LED package comprises a diode that works as a light-emitting diode for emitting light and as a sensing diode for detecting at least one physical quantity. The multi-die LED package is able to provide desired luminance and color independent of aging, temperature or other effects.
Abstract:
A dimmable driver is disclosed with multiple channels, universal dimming over multiple input voltage ranges and a web-based user interface for dimming settings.
Abstract:
An LED driver capable of controlling color/color temperature with a power carrier connects a power switch with a dimmer for linking an input end of an LED color/color temperature output controller. An LED array disposed on an output end of the controller allows a power cord to transmit a controlling signal. A synchronous and dimmer action detection differentiates an action of the dimmer or pressing times from an ON/OFF count, so that the LED array presents different color temperatures/colors accordingly. An LED condition memory saves the color temperature/color according to an output signal. In adjusting illumination, the dimmer changes an output current for altering the power of the LED array accordingly, which presents a stable light but avoids deviating the color temperature/color and flickering.
Abstract:
Provided are a method, apparatus and system for controlling a light source. The method comprises: acquiring an adjustment signal and determining a dimming item according to the adjustment signal; the dimming item being composed of the value and/or value range of at least one characteristics parameter of a pulse drive signal; converting the adjustment signal into the pulse drive signal indicated by the dimming item; controlling an adjustment switch by means of the pulse drive signal, so as to output a voltage including a chopped wave voltage corresponding to the dimming item, thereby transmitting adjustment information about the colour and/or brightness of the light source by means of the voltage including the chopped wave voltage. The method, apparatus and system can achieve the function of adjusting the colour and/or brightness of the light source.