A resonant DC-DC converter may include an input for inputting a DC supply voltage, an output for providing a DC voltage to a load, an output rectifier to convert the converter voltage into a DC voltage, a resonant half-bridge inverter comprising two switches in series with a first serial resonant circuit to adjust the output current of the converter, and a second serial resonant circuit to block DC current in the converter and provide current continuity within the converter. The resonance of the first serial resonant circuit is measured after every start of the converter and each measurement defines the switching frequency of the half-bridge inverter. The switches of the half-bridge inverter wherein the driving of the half-bridge inverter includes a key gap during operation thereof. The resonance frequency of the second serial resonant circuit is at least slightly above the switching frequency of the half-bridge inverter.

A light emitting element driving device includes a receiver that receives a predetermined communication signal transmitted across a communication line, a generator that generates a reference signal based on the start time point of a start bit in the predetermined communication signal, and a determiner that determines, based on the reference signal, the timing of switching a light emitting element from extinction to lighting. The predetermined communication signal is a signal in which the start bit with a first logic level is transmitted at a prescribed period from a transmitter and in which the data bits succeeding each start bit do not have a second logic level a predetermined number of times or more consecutively.

A light emitting element driving device includes a receiver that receives a predetermined communication signal transmitted across a communication line, a generator that generates a reference signal based on the start time point of a start bit in the predetermined communication signal, and a determiner that determines, based on the reference signal, the timing of switching a light emitting element from extinction to lighting. The predetermined communication signal is a signal in which the start bit with a first logic level is transmitted at a prescribed period from a transmitter and in which the data bits succeeding each start bit do not have a second logic level a predetermined number of times or more consecutively.

Inventive methods and apparatus for interactive control of a lighting environment. In some embodiments an interactive system for controlling redirectable lighting in a lighting environment may be provided. In some embodiments systems and methods may be provided that enable the display of adjustable lighting parameters in a virtual environment.

Inventive methods and apparatus for interactive control of a lighting environment. In some embodiments an interactive system for controlling redirectable lighting in a lighting environment may be provided. In some embodiments systems and methods may be provided that enable the display of adjustable lighting parameters in a virtual environment.

System and method for controlling one or more light emitting diodes. For example, the system for controlling one or more light emitting diodes includes a current regulation circuit coupled to a cathode of one or more light emitting diodes. The one or more light emitting diodes include the cathode and an anode configured to receive a rectified voltage. Additionally, the system includes a control circuit coupled to the cathode of the one or more light emitting diodes. The control circuit is configured to receive a first voltage from the cathode of the one or more light emitting diodes, compare a second voltage and a threshold voltage, and generate a control signal based at least in part on the second voltage and the threshold voltage. The second voltage indicates a magnitude of the first voltage.

System and method for controlling one or more light emitting diodes. For example, the system for controlling one or more light emitting diodes includes a current regulation circuit coupled to a cathode of one or more light emitting diodes. The one or more light emitting diodes include the cathode and an anode configured to receive a rectified voltage. Additionally, the system includes a control circuit coupled to the cathode of the one or more light emitting diodes. The control circuit is configured to receive a first voltage from the cathode of the one or more light emitting diodes, compare a second voltage and a threshold voltage, and generate a control signal based at least in part on the second voltage and the threshold voltage. The second voltage indicates a magnitude of the first voltage.

optoelectronic circuit intended to receive a variable voltage containing an alternation of rising and falling phases. The optoelectronic circuit includes light-emitting diodes and a switching device capable of allowing or of interrupting the flowing of a current through each light-emitting diode. Each light-emitting diode is covered with a photoluminescent layer. The photoluminescent layer covering at least one of the light-emitting diodes includes at least one first luminophore having a first decay constant and at least one second luminophore having a second decay constant different from the first decay constant.

optoelectronic circuit intended to receive a variable voltage containing an alternation of rising and falling phases. The optoelectronic circuit includes light-emitting diodes and a switching device capable of allowing or of interrupting the flowing of a current through each light-emitting diode. Each light-emitting diode is covered with a photoluminescent layer. The photoluminescent layer covering at least one of the light-emitting diodes includes at least one first luminophore having a first decay constant and at least one second luminophore having a second decay constant different from the first decay constant.

Provided is a method and apparatus for controlling light attributes of a lighting device, and a lighting system and includes an indicator that receives an input, and sends to a control unit, a signal for switching light attribute of the lighting device; and the control unit determines whether a first switching signal or a second switching signal from the indicator is received during a light emission period after the lighting device is powered on, and if it is determined that the first switching signal is received, switching a current light attribute to another light attribute, or if it is determined that the second switching signal is received, switching the current light attribute to a light attribute indicated by the second switching signal such that when a specific light attribute is indicated by the second switching signal, the light attribute can still be adjusted with the first switching signal.