Koninklijke Philips Corporation N.V.

U.S. Philips Corporation

Philips Lighting Holding B.v.

Peter Lürkens

Carsten Deppe

Holger Mönch

Dieter Gerling

Bernd Ackermann

Christian Hattrup

Thomas Scheel

Xaver Riederer

Albert Garcia Tormo

Matthias Wendt

Reinhold Elferich

Georg Sauerländer

Thomas Dürbaum

Tobias Georg Tolle

Gero Heusler

Winston Donald Couwenberg

Antonius Johannes Joseph Wismans

Andreas Tücks

Jorg Meyer

Johannis Antonie Toonen

Roy Hendrik Zundert

Wolfgang Efftinge

Ralf Kröger

The present invention relates to a converter circuit () for reducing a nominal capacitor voltage, the converter circuit () comprising: an input node (TI), which is configured to receive an input voltage (V); an output node (TO; TO), which is configured to supply an output voltage (V) to a load (R; R); and a capacitor (C; C), which is coupled to the load so that the input voltage is divided between the capacitor (C; C) and the load (R; R) and which is configured to be charged up to a voltage corresponding to a differential voltage between the input voltage (V) and the output voltage (V).

Converter circuit for reducing a nominal capacitor voltage

A high voltage transformer () includes a magnetic core (); a low voltage winding (); a high voltage winding (); at least one inner sleeve (); and a coil bobbin () for carrying the high voltage winding (). The coil bobbin () is configured to be arranged inside the at least one inner sleeve () and configured to be attached to the at least one inner sleeve () at an outer perimeter of the at least one inner sleeve (). The coil bobbin () includes at least one field-control electrode (), which is adapted to shape an electric field generated by the high voltage winding ().

High voltage transformer comprising a coil bobbin for carrying a high voltage winding

A lighting device for generating colored and white light. According to the invention the lighting device comprises at least one light source () emitting blue or ultraviolet light and a color conversion unit () for converting said blue or ultraviolet light into visible light comprising at least two sections (), at least one section () of which being a transparent or translucent color converting section, said color conversion unit () being arranged for alternately illuminating said at least two sections () 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.

Colored and white light generating lighting device

Current switching point determination devices use two comparators with fixed threshold values. A power inverter control device for switching point determination is provided which includes a filter circuit and a subsequent single comparator. By this arrangement, the time event is independent of the amplitude and for sufficiently small frequencies also of the frequency.

Power inverter control device for switching point determination

The invention relates to a resonant power LED control circuit for the independent, simultaneous brightness and color or color temperature control of two LEDs () or two groups of LEDs, comprising a single resonant converter which is essentially formed from a half or full bridge DC/AC converter () with a control unit (), a resonant capacitor, and a transformer ().

Resonant power LED control circuit with brightness and color control

The invention relates to a DC/DC converter for use in a decentralized power generation system. If a DC/DC converter is physically separated from a power receiving component and connected to such a power receiving component via a DC bus, a short-circuit on the DC bus may endanger the system and service personnel. In order to minimize such a risk, it is proposed that the DC/DC converter comprises a converting component for DC/DC converting a direct current supplied by a power generating unit and for supplying a resulting converted direct current to a DC bus, and that the DC/DC converter comprises in addition a control component arranged to monitor a voltage at the outputs of the DC/DC converter and to cause the converting component to enter a short-circuit protection mode if the monitored voltage lies below a predetermined voltage threshold. The invention relates equally to a corresponding system and to a corresponding method.

DC/DC converter and decentralized power generation system comprising a DC/DC converter

A method of determining a zero point of a current sensor in a circuit arrangement for operating a gas discharge lamp includes switching off the current through the sensor for a short period during a first half wave and determining a first test value. Then the current through the sensor is switched off for a short period during a second half wave having a different polarity and a second test value is determined. The average value of the two test values is formed and the zero point is determined using the average value. It is prevented thereby that the zero point drifts during lamp operation, and that amplitudes of the positive and negative half waves of the lamp current are formed differently.

Method of determining a zero point of a current sensor

A circuit and a method for operation of a gas discharge lamp includes a switching transformer having a switch, a converter, inductor and a controller in a control loop for measuring a lamp voltage and setting a desired power. The switching transformer further includes a second control loop used for adjusting the switching transformer to individual lamp conditions.

Circuit and method for dynamic adjustment of operation conditions of a gas discharge lamp

A projection system for image reproduction includes at least one lamp and sensor for generating a sensor signal for monitoring changes in the luminous flux generated by the lamp and for compensating these changes through a suitable control of the image reproduction. The projection system further includes a device for eliminating substantially periodic interference components from the sensor signal generated by the sensor. These interference components may be generated by an optical component such as a color modulator of the projection system. The projection system provides substantially interference-free compensation of fluctuations in the luminous flux generated by the lamp, for example, owing to an unstable arc discharge. Further, the positioning of the sensor in the projection system may not be critical.

Projection system

The invention relates to a method for operating a discharge lampincluding two electrodesThe method comprises applying to the electrodes an alternating current I. In order to improve the performance of the lamp and to increase the life time of the lamp, it is proposed that the alternating current has a direct current component DC for compensating a temperature difference between the two electrodes. The direct current component is selected more specifically such that a first electrode, which is expected to have a lower temperature than the second electrode, functions as anode for the direct current component, while the second electrode functions as cathode for the direct current component. The invention relates equally to an electronic circuit and to a software program for operating a discharge lamp correspondingly, as well as to a lighting system comprising a discharge lamp and means for operating this discharge lamp correspondingly.

Electrode temperature differential operation of a discharge lamp

A circuit includes a converter for converting an a.c. voltage into a d.c. voltage. The converter has a diode half-bridge, a switch half-bridge, and two d.c. rails. Further, the converter has a second converter for converting the a.c. voltage into a second d.c. voltage.

Circuit having a second ac/dc converter

The invention relates to an electronic circuit for igniting a high-pressure lamp. A resonant circuitof the circuit is used to supply the ignition voltage for the high-pressure lamp. To enable an exact adjustment of the resonance frequency in the resonant circuit, it is proposed that the circuit also comprises converterfor generating an alternating voltage with which the resonant circuitis excited and an oscillatorfor driving the converter, the fundamental frequency of the output voltage of the oscillator being at least in proximity to an integral fraction of the resonance frequency of the resonant circuit. Finally, it is proposed that the circuit includes a feedbackfrom the resonant circuitto the oscillator, whereby the fundamental frequency of the output voltage of the oscillator is so tuned that the resulting frequency of the output voltage of the oscillator corresponds substantially exactly to the integral fraction of the resonance frequency. The invention also relates to a corresponding lighting installation and a corresponding method.

Circuit and method of igniting a high-pressure lamp

The invention describes a method of transmitting information between an information transmitter and an information receiver, the potential difference of which moves in cycles between a minimum value and a maximum value and is situated at the minimum value for regular intervals; having the steps: provision of information over the time interval or determining the time interval in which the potential difference between information transmitter and information receiver assumes its minimum value; closing of a switching means of the information transmitter in relation to an information memory assigned to the information receiver, only within the time interval; and transmission and storage of the information in the information memory.

Method of transmitting information between an information transmitter and an information receiver

The invention relates to an electronic circuit and a method of supplying energy to a high-pressure gas-discharge lamp H,. The electronic circuit comprises a line-supply input sectionto receive and convert an a.c. voltage from an a.c. line-supply system, an energy storage meansto store the energy put out by the line-supply input sectionand a lamp-current regulating unitthat is supplied with an input voltage Uby the line-supply input sectionvia the energy storage meansand that makes available a lamp current Ifor a high-pressure gas-discharge lamp II,. To make it possible for the energy storage meansto be particularly small, it is proposed that the lamp-current regulating unithave a power section L, D, C, S, A, A, K having a transconductive property. If there is a drop in the input voltage U, this property then automatically produces a reduction in the lamp current Imade available to a high-pressure gas-discharge lamp, H. This ensures a particularly fast adjustment to voltage fluctuations. The invention also relates to a corresponding method.

Electronic circuit and method of supplying energy to a high-pressure gas-discharge lamp

The invention relates to an image projector with a High-Intensity-Discharge HID lamp () and a method of operating it. Such lamps have the disadvantage that their voltaic arc jumps back and forth between different positions at unforeseeable times during operation. This so-called arc jumping has the effect of changing the brightness, i.e. the overall brightness and/or the brightness distribution of the light emitted by the HID lamp (). For the viewer of an image projected with such a projector, this effect appears as a jolt of this projected image. To avoid such effects for the viewer, it is first proposed according to the invention that changes in the brightness of the light in the image projector's beam path are detected. As soon as a change in brightness caused by an arc jump has been detected, this brightness is reset to a brightness detected at a moment t-before the arc jump, in order subsequently to convert it during a predetermined time interval T to the brightness resulting from the arc jump. This resetting must occur so soon after the arc jump, and the conversion so slowly, that the changes in the brightness of the light incident on a picture screen device () resulting from the arc jump, the reset, and the conversion are not perceptible to the human eye.

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Aachen, Germany

Peter Lürkens