Abstract: A good way to avoid extreme current levels when supplying large amounts of power is to increase the voltage. The easiest way to do this is connecting the radiation elements (e.g. laser diode pixels) in series (La1 to La-n). In such a pixelated driver, the amount of components and complexity per pixel are reduced by connecting as many radiation elements as possible in series, supplying the string by one current controlled driver (Is), shortening pixels which should be in off state by a switch in parallel (40-1 to 40-n) to the radiation element, storing binary on/off information (30-1 to 30-n) for each pixel locally, creating a floating supply (20-1 to 20-n) for the switches, and managing information transfer to the floating storage and switches.

Abstract: The invention relates to a circuit arrangement (1) for controlling at least one load (D1, D2, D3). In order to provide means for extracting an auxiliary power supply from a current source in order to control shunt switching, the inventive circuit arrangement (1) comprises an input terminal (11) for connection to a power supply (30), an output terminal (12) for connection to at least one load element (20, 21, 22, 23), a control circuit (10), comprising a control device (13), which is adapted to control at least one load element (20, 21, 22, 23), and an energy storage device (C), which is adapted to supply power to the control device (13). A controllable bypass switch (M4) is further provided, wherein said bypass switch (M4) and said control circuit (10) are connected in parallel and are connected between said input terminal (11) and said output terminal (12). The circuit arrangement (1) is adapted to operate the bypass switch (M4) to control the power provided to the control circuit.

Abstract: The invention relates to solid state light source, a use of a driver circuit for driving a light emitting element (150) of a solid state light source, a method for driving a light emitting element (150) of a solid state light source and a corresponding computer program. The invention provides that for a large amount of an AC period the light emitting element (150) is directly supplied with the AC input directly forwarded by the driver circuit, wherein nevertheless it is prevented that power exceeding a desired level reaches the light emitting element (150). The invention is aimed at a realization with simplified components and/or reduced costs in comparison to known techniques.

Abstract: Driver circuits (1) for driving load circuits (2, 3) receive source signals from sources and provide feeding signals to the load circuits (2,3) and charging signals to capacitor circuits (21). These capacitor circuits (21) provide supporting signals to the load circuits (2, 3) in addition to the feeding signals. By providing the driver circuits (1) with control circuits (22) for controlling the supporting signals, the capacitor circuits (21) can become less bulky/costly and/or will limit the lifetime of the driver circuits (1) to a smaller extent. Further, these driver circuits (1) may get improved efficiencies. Said controlling may comprise controlling moments in time at which the supporting signals are offered to the load circuits (2, 3) or not, and/or may comprise controlling sizes of the supporting signals, and/or may be done in response to detection results from detectors (23) for detecting parameters of one or more signals. Said controlling may comprise switching via switches (24).

Abstract: Driver circuits (1) for driving load circuits (2) comprising first and second light circuits (21-22, 71-72) are in first/second modes for input voltages having first/second voltage amplitudes, the second voltage amplitudes being larger than the first voltage amplitudes. The first light circuits (21, 71) are on in the first and second modes. The second light circuits (22, 72) are off in the first modes and are on in the second modes. A control circuit (21, 71) in dependence of the modes to extend control. These currents may get smaller current amplitudes in higher modes. Light outputs of the first light circuit (21, 71) may get smaller in higher modes. A total light output of all light circuits (21-22, 71-72) may remain substantially constant during all modes.

Abstract: An LED lamp is disclosed herein. In one embodiment, the LED lamp comprises one LED unit arranged in a housing, a first and a second lamp cap being arranged spaced from each other on opposing ends of the housing, said lamp caps each comprising at least one contact element for connecting said LED unit with a lamp fixture. In one embodiment, said first lamp cap comprises contact breaking means, configured to electrically disconnect said contact elements of said first and second lamp caps from each other when said LED lamp is removed from said lamp fixture.

Abstract: The invention relates to a power supply circuit (10) and methods for supplying electrical power to at least one load output. The circuit comprises a main power supply unit (12) with a voltage input (14), a main switching element (26) and a reactive element (28). The switching element (26) is controllable to deliver an output voltage or current (I out). Output units (20a, 20b, 20c) with load outputs are connected to a main power supply unit (12). In order to drive loads connected to the load outputs, e.g. LEDs, OLEDs or laser diodes, with exact pulses, each output unit (20a, 20b, 20c) has a load switching element (38) to connect or disconnect the main power supply unit (12) to or from the load output. There are further provided switched capacitor units (34), each with a capacitor (C) and a capacitor switching element (40). The capacitor units may be operated such that the capacitors remain essentially charged at different voltage levels.

Abstract: Bleeder circuits (1) for combinations of phase cutting dimmers (2) and light emitting diode circuits (3) comprise active circuitry (4) to increase a number of options. The active circuitry (4) may comprise a current limiting circuit (5) for limiting a current flowing through the bleeder circuit (1). The active circuitry (4) may comprise a voltage detecting circuit (6) for activating or deactivating, in response to a detection result, the current limiting circuit (5) and may comprise control circuitry such as a micro processor circuit (7) for controlling the current limiting circuit (5) and may comprise a control circuit (9) for using information derived from a current flowing through the light emitting diode circuit (3) for controlling the current limiting circuit (5) and for controlling at least a part of the light emitting diode circuit (3) that comprises anti-parallel light emitting diodes (31-32) or serial and/or parallel light emitting diodes (33-36).

Abstract: The present invention relates to a bidirectional semiconductor switch (M1, M2) with extremely low control power consumption and a bootstrap circuit which allows reliable start of operation of the switch and the hosting device after unlimited duration of mains interruptions. Intelligent control options are provided by operating from a small energy storage and no extra means are required to recover from a depleted energy storage condition. The absence of audible noise and mechanical wear also enables more frequent recharging cycles and allows smaller and thus cheaper energy storage components.

Abstract: In light emitting diode circuits (1) comprising serially coupled first and second circuits (11, 12) with first and second light emitting diodes, third circuits (13) are coupled in parallel with the second circuits (12) for controlling the first light emitting diodes in the first circuits (11) and/or third light emitting diodes in fourth circuits (14). This allows more options, more optimizations, more flexibility and/or more efficiency. The light emitting diode circuit (1) receives a supply voltage from a source (2, 3) for feeding the light emitting diode circuit (1). The third circuit (13) receives a feeding voltage from the second circuit (12) for feeding the third circuit (13). The feeding voltage may be a voltage present across the second circuit (12). The third circuit (13) may further control the second light emitting diodes in the second circuit (12).

Abstract: A method for driving a high-pressure gas discharge lamp of a projector system, which is suitable to produce and to supply to a light valve device during a projection interval (4) a light beam of a basic color which is selected from several basic colors (G, R, B). The lamp is driven by a lamp current. During said projection interval light valves of the light valve device are controlled in a pulse width modulation manner to have each valve provide a respective wanted light integral over said projection interval. During at least one of a number of successive projection intervals associated with one basic color a magnitude of the lamp current is temporarily reduced for at least a time that all light valves can be controlled for said one basic color.

Abstract: The present invention relates to a driver device (40; 50; 60) and a corresponding driving method for driving a load (12), in particular an LED unit (12) including one or more LEDs, said driver device comprising a power input unit (14) for receiving an input voltage (V10) from an external power supply (18) and for providing a rectified supply voltage (V12), a controllable resistor (48) for providing a load current (I L) to power the load (12), a frequency filter (42) connected to the power input unit (14) for providing a voltage (V18) to the load (12), wherein the frequency filter (42) is partially coupled in parallel to the load (12) and connected to the controllable resistor (48) to provide a substantially constant electrical power to the load (12).

Abstract: The present invention relates to an LED lamp (1) adapted for operation with an alternating current. The LED retrofit lamp (1) comprises a LED unit (7, 7?, 7?, 7??) and a compensation circuit with a controllable switching device (9, 9?), connected parallel to said LED unit (7, 7?, 7?, 7??) to provide an alternate current path. A control unit (10, 10?, 10?) is adapted to control said switching device (9, 9?) in a compensation mode in which said switching device (9, 9?) is set to the conducting state for the duration of a shunt period in each half cycle of the alternating current to allow adapting the power/current of the inventive LED lamp (1), so that a versatile and optimized operation of the lamp (1) is possible.

Abstract: The invention relates to a method and a device for driving an LED string of a first LED segment (11) and at least one further LED segment (12, 13, 14) connected in series. Each LED segment has at least one light emitting diode, LED. The LED string is powered by a rectified AC mains voltage. The first LED segment (11) is powered when the rectified AC mains voltage is above a first voltage level, and the first LED segment and the further LED segment are powered when the rectified AC mains voltage is above a second voltage level higher than the first voltage level. The first LED segment emits light having a first color temperature, and the further LED segment emits light having a second color temperature higher than the first color temperature. The light emitted by the first LED segment and the light emitted by the further LED segment are superimposed. The color temperature change of the light emitted by the LED string, when dimmed, resembles the color temperature change of an incandescent lamp.

Abstract: Disclosed is a lighting device including a circuit including at least two parallel-connected light-emitting diodes of opposite pole in a first parallel branch and comprising at least two parallel-connected light-emitting diodes of opposite pole in a second parallel branch, and also including a capacitor and a coil. At least one of the diodes emits red light, blue light, and/or white light.

Abstract: An LED lamp (1) is provided, having at least one LED unit (4) arranged in a housing (2), a first (5, 5?, 5?, 5??) and a second (6) lamp cap being arranged spaced from each other on opposing ends of the housing (2), said lamp caps (5, 5?, 5?, 5??, 6) each comprising at least one contact element for connecting said LED unit (4) with a lamp fixture. To enhance the safety of the LED lamp (1) during removal of the lamp (1) from the fixture, said first lamp cap (5, 5?, 5?, 5??) comprises contact breaking means (40, 40?, 40?), configured to electrically disconnect said contact elements of said first (5, 5?, 5?, 5?) and second (6) lamp caps from each other when said LED lamp (1) is removed from said lamp fixture.

Abstract: Driver circuits (1) for driving load circuits (2) comprising first and second light circuits (21-22, 71-72) are in first/second modes for input voltages having first/second voltage amplitudes, the second voltage amplitudes being larger than the first voltage amplitudes. The first light circuits (21, 71) are on in the first and second modes. The second light circuits (22, 72) are off in the first modes and are on in the second modes. A control circuit (21, 71) in dependence of the modes to extend control. These currents may get smaller current amplitudes in higher modes. Light outputs of the first light circuit (21, 71) may get smaller in higher modes. A total light output of all light circuits (21-22, 71-72) may remain substantially constant during all modes.

Abstract: Driver circuits (1) for driving load circuits (2, 3) receive source signals from sources and provide feeding signals to the load circuits (2,3) and charging signals to capacitor circuits (21). These capacitor circuits (21) provide supporting signals to the load circuits (2, 3) in addition to the feeding signals. By providing the driver circuits (1) with control circuits (22) for controlling the supporting signals, the capacitor circuits (21) can become less bulky/costly and/or will limit the lifetime of the driver circuits (1) to a smaller extent. Further, these driver circuits (1) may get improved efficiencies. Said controlling may comprise controlling moments in time at which the supporting signals are offered to the load circuits (2, 3) or not, and/or may comprise controlling sizes of the supporting signals, and/or may be done in response to detection results from detectors (23) for detecting parameters of one or more signals. Said controlling may comprise switching via switches (24).

Abstract: Disclosed is a method for adjusting light output of a projector that includes compiling a switching sequence having long and short segments for the controllable elements of a display unit, a long segment being of a duration greater than or equal to a threshold and a short segment being of a duration less than the threshold; obtaining a light output adjustment measure by which the light output is to be adjusted; generating a light pulse sequence such that the duration of a light pulse corresponds to the light output adjustment measure; and arranging the light pulse relative to the switching sequence such that the activation of the light pulse does not occur during a short segment, wherein the predefined threshold is a time duration of the light pulse at a lowest dimming level such that the light pulse has settled by the time the long segment ends.

Abstract: An image projection method comprises the steps of a) obtaining an image pixel array for the image to be projected; b) obtaining a plurality of pixel allocation arrays for the image pixel array, whereby each pixel allocation array comprises occupied elements and vacant elements; c) generating a trigger pulse train for a laser light source according to a pixel allocation array, whereby a trigger pulse is generated for each occupied element; d) generating a modulation signal for the laser light source; e) switching the laser light source with the trigger pulse train and modulating the laser light source with the modulation signal to generate a laser light pulse sequence for a sub-frame image; f) and scanning the laser light pulse sequence to traverse the display; thereby, the steps c) to f) are carried out for each pixel allocation array so that the image appears on the display.