Abstract: The invention provides a switched mode power converter adapted for zero-voltage transition operation, wherein the converter comprises a half-bridge, having a first power switch (206) and a second power switch, a generator (201) adapted for generating a switching signal S1 after a first period of time, wherein the first period of time starts at the switching off of the second power switch, a controller (202) for converting the switching signal S1 into a control signal S2, wherein the first power switch (206) is switched on in case of the control signal S2, wherein the controller (202) comprises a detector (205), wherein the detector (205) is adapted to generate a first signal S3 in case the voltage over the first power switch (206) is decreasing, a processor (203), wherein the processor (203) is adapted to generate a trigger signal S4 in case of a switching signal S1 and while the first signal S3 is not present, a storage element (204), wherein the storage element (204) is adapted to generate the control signa

Abstract: Disclosed is a light module package including a mounting substrate for mounting and electrically contacting at least one light emitting diode and a ceramic layer disposed in a path of light emitted by the light emitting diode. The ceramic layer includes a wavelength converting material and the light emitting diode is disposed between the ceramic layer and the mounting substrate. The light module package also includes a light sensor disposed at the mounting substrate for detecting a luminous output of the light emitting diode in order to control the brightness and/or the color of the light leaving the light module. The ceramic layer is only partly translucent to shield the light sensor against ambient light.

Abstract: The invention relates to a transformer (12) with a planar primary winding and a planar secondary winding. In order to support the heat dissipation during operation, each winding is integrated on a substrate in at least one dedicated PCB (30, 40). The PCBs (30, 40) are separated from each other by a non-ferromagnetic and electrically insulating material (50). The material: (50) transfers heat better than the substrates. The invention relates equally to an apparatus comprising such a transformer (12).

Abstract: The invention provides a device for a computer tomography gantry (91) for transferring contactlessly electrical energy from a stationary part of the gantry (92) to a rotary part of the gantry (93), wherein the device comprises a first power transformer, a second power transformer, wherein the first and the second power transformers are adapted for transferring the electrical energy, wherein the first power transformer comprises a first winding (506, 507, 542, 602, 601, 1202, 1301, 1401) out of the group consisting of a first set of primary windings and a first set of secondary windings of the first power transformer, wherein the second power transformer comprises a second winding (508, 509, 543, 603, 604, 1204, 1302, 1402) out of the group consisting of a second set of primary windings and a second set of secondary windings of the second power transformer, wherein the first set of primary windings and the second set of primary windings being adapted to be mounted on the stationary part of the gantry, wherein

Abstract: The present invention relates to a device and method for controlling the color point of an LED light source (50). Color point control is a most interesting product feature both for white and colored LED light sources. In known methods for the color control of RGB LED light sources use is made of flux and color sensors. However, there are difficulties with respect to sensing quickly changing ambient light, deeply dimmed colors, coordinating the measurements with the switching of the LEDs, and controlling the color in LED light units comprising a number of independent LED lamps, e.g. segmented wall washers and LCD backlights. It is proposed according to the present invention to control the color of the LED light source (50), using a model-based feed forward approach. Factors relating the parameters controlling the LED currents to the brightness for the different colors (and segments) are stored and used for open loop control. A slow-running procedure continuously measures and updates these factors.

Abstract: The invention relates to a light sensor, particularly for LED-based lamps. The light sensor comprises at least one photosensor (1) and a temperature sensor (2). The photosensor (1) and the temperature sensor (2) are integrated on a common substrate in a common housing.

Abstract: The invention relates to a driver circuit arrangement (1?) for driving a plurality of individually switchable electrical subsystems (A?, B?, C?), such as (arrangements of) LEDs (9-A, 9-B, 9-C). Each subsystem has at least one energy storage device (10-A, 10-B, 10-C), such that when the subsystem is disconnected from the main source (7) of electrical energy, the energy storage device can supply energy to the device(s) of the subsystem. By furthermore providing at least one subswitch (13-A, 13-B, 13-C) in the subsystem, between the energy storage device and an electrical device of the subsystem, control over the device is still possible when the subsystem is disconnected form the main source of electrical energy.

Abstract: This invention relates to a color controlled light source comprising a plurality of colored light elements; a detector for detecting the light output of the light source and generating a detection signal; and a color control unit for generating driving signals to said light elements on the basis of said detection signal and a predetermined target color point of the light output of the light source. In order to enable detection of contributions from individual light elements to the light output of the light source, the light source further comprises a modulator for individual signature modulation of the driving signal to each one of said light elements; and a corresponding demodulator for demodulation of said detection signal and generation of actual, i.e. measured, values of the output of the individual light elements. The color control unit determines nominal values of the light output of each light element for obtaining said target color point, and compares the actual values with the nominal values.

Abstract: The invention relates to alighting device which comprises an at least partly reflective electroactive polymer actuator (1) and a lighting element (2) illuminating the electroactive polymer actuator. A voltage control arrangement (4) for driving the electroactive polymer actuator (1) with a spatially varying voltage distribution is provided.

Abstract: The present invention describes a winding for a transformer comprising first (60) and second (70) planar sections which are arranged parallel to each other. First (1, e.g., from 602 to 603)) and second (2, e.g., from 703 to 704)) current paths are arranged on the first and second planar sections. The first and second current paths are connected to each other by means of an interconnection (603/703). The first and second current (603/703) paths are respectively angled with respect to a direction along which the first and second planar sections are extending.

Abstract: Adjusting a driving signal for a lighting device by obtaining a temperature of the lighting device, and adjusting at least one parameter of a conversion procedure depending on the obtained temperature. Further a set-point of a desired colour and/or brightness is converted into a set-point of colour sensor coordinates with the conversion procedure. The actual colour values of the lighting device are obtained, and the driving signal is adjusted based on a difference between the colour sensor coordinates set-point and the obtained colour values.

Abstract: In a safety device for a tank system with a tank pipe 1 which has a pliable region and a rigid region, a reinforcing element 7 is allocated to the rigid region of the tank pipe 1. The reinforcing element 7 is hollow and is in contact with the entire circumference of the tank pipe 1 with its interior contour.

Abstract: Disclosed are light emitting diode circuits employing first sub-circuits including first light emitting diodes and connected in parallel with second sub-circuits including second light emitting diodes and switches for, in conducting states, switching on the second light emitting diodes and switching off the first light emitting diodes and for, in non-conducting states, switching off the second light emitting diodes and switching on the first light emitting diodes. The first sub-circuits and the second sub-circuits have different signal characteristics such as different minimum threshold voltages to be realized by using different kinds of light emitting diodes, by using different total numbers of serial light emitting diodes, or by adding threshold voltage elements to the first sub-circuits.

Abstract: The invention relates to a mounting substrate (10) for mounting and electrically contacting at least one light emitting diode (20), a ceramic layer (40) disposed in a path of light emitted by the light emitting diode (20), wherein the ceramic layer (40) comprises a wavelength converting material, the light emitting diode (20) disposed between the ceramic layer (40) and the mounting substrate (10), a light sensor (30) disposed at the mounting substrate (10) detecting a luminous output of the light emitting diode (20) in order to control the brightness and/or the color of the light leaving the light module (1), wherein the ceramic layer (40) is only partly translucent to shield the light sensor (30) against ambient light.

Abstract: In a method and a driver circuit for operating one or more light emitting diodes, LEDs, an alternating supply current is generated and transformed to an alternating secondary winding voltage. Using rectifier means, such as diodes or synchronous switches, the alternating secondary winding voltage is converted to a substantially constant load current by using a buffer element, such as an output choke, i.e. a suitable inductor. The power transferred from the power source to the LEDs may be controlled by frequency control of the alternating supply current.

Abstract: A lighting device for generating colored and white light. According to the invention the lighting device comprises at least one light source (1, 4) emitting blue or ultraviolet light and a color conversion unit (2, 5) for converting said blue or ultraviolet light into visible light comprising at least two sections (2a, 2b, 2c, 6a, 6b, 6c, 6d), at least one section (2c, 6d) of which being a transparent or translucent color converting section, said color conversion unit (2, 5) being arranged for alternately illuminating said at least two sections (2a, 2b, 2c, 6a, 6b, 6c, 6d) with said blue or ultraviolet light, said at least one color converting section containing luminescent material, wherein said luminescent material is a luminescent organic dye in a polymer matrix or a crystalline inorganic luminescent material.

Abstract: The invention relates to a lighting device that may particularly be used as an LCD backlight and that comprises an array of light emitters (11.1, 11.2) which are optionally separated by optical barriers (13). The light emitters (11.1, 11.2) may particularly be realized by groups of LEDs (12.1, 12.2) of different colors, for example red, green and blue. Local control units (16), driving units (15.1, 15.2), and sensor units (14) are provided to control the individual light output of the light emitters, wherein at least one of these components is shared by two or more light emitters (11.1, 11.2).

Abstract: A lighting device (1) having at least two light sources (5), and in particular LED's, having a light distributing device (3) for distributing the light emitted by the light sources (5), the light sources (5) being arranged inside the light distributing device (3), having a diffuser surface (4) arranged on the light distributing device (3) and having at least one separating surface (10) arranged inside the light distributing device (3) to divide the light distributing device (3) into at least two sub-regions (31, 32) for light distribution.

Abstract: Operating a lighting device by acquiring a target brightness level of at least one solid-state lighting unit, and determining a reference driving current amplitude for obtaining the target brightness level. If the reference driving current amplitude is below an optimum driving current amplitude, the solid-state lighting unit is operated at the optimum driving current amplitude, which is pulse-width modulated to obtain the target brightness level.

Abstract: The present invention describes a winding for a transformer comprising first (60) and second (70) planar sections which are arranged parallel to each other First (1, e.g., from 602 to 603)) and second (2, e.g., from 703 to 704)) current paths are arranged on the first and second planar sections. The first and second current paths are connected to each other by means of an interconnection (603/703). The first and second current (603/703) paths are respectively angled with respect to a direction along which the first and second planar sections are extending.