摘要:
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).
摘要:
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.
摘要:
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.
摘要:
The invention relates to a circuit (2) comprising at least two parallel-connected light-emitting diodes (4, 5) opposite poled in a first parallel branch (12) and comprising at least two parallel-connected light-emitting diodes (6, 7) opposite poled in a second parallel branch (13), and also comprising a capacitor (8) and a coil (9). According to the invention, the first parallel branch (12) has a capacitor (8) and the second parallel branch (13) has the coil (9). On account of the capacitive parallel branch (10) and the inductive parallel branch (11), idle currents arise which are phase-shifted with respect to one another. The idle currents compensate one another and light changes of the oppositely-poled diode pairs take place at different points in time. A light current is then smoothed.
摘要:
The invention describes a method of shutting down a high pressure discharge lamp (1) in which a pair of electrodes (2) is disposed in an arc tube (3), which method comprises reducing, upon receipt of a shut-down request (SR), the lamp power (P) towards a reduced power level (PR) required to sustain a long-term arc discharge between the electrodes (2), and driving the lamp (1) towards the reduced power level (PR) for a reduced power duration before completely shutting down the lamp power (P), whereby, prior to reducing the lamp power (P) towards the reduced power level (PR), the lamp power (P) is reduced to an undershoot power level (Pu), which undershoot power level (Pu) is lower than the reduced power level (PR) required to sustain a long-term arc discharge between the electrodes (2), and the lamp is driven at this undershoot power level (Pu) for an undershoot power duration (tu) before increasing the lamp power (P) again to approach the reduced power level (PR). Moreover the invention describes an appropriate driving unit (4) for driving a high pressure discharge lamp (1) and an image rendering system (40), particularly a projector system, comprising such a driving unit (4).
摘要:
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.
摘要:
A method for operating a projection system (1) is described, wherein a brightness level (B1, B2, B3, B4, B5, B6) in an image (IM) is represented by the total length of a number of light switch-on phases within a particular image cycle (VT). A high pressure discharge lamp (2) of the projection system (1) is operated via a lamp driver with an essentially square-wave alternating current (IL) SO that an overshoot sequence (0), which occurs in the alternating current (IL) after a current zero crossing during operation of the high pressure discharge lamp (2), has a frequency so high that for each possible brightness level at least one full period (P) of the overshoot sequence (0) lies essentially within a light switch-on or switch-off phase (ts) following the zero crossing. A projection system (1) and a lamp driver (10) for a high pressure discharge lamp (2) in such a projection system (1) are also described.
摘要:
The invention describes a method of driving a discharge lamp (1), wherein a blackening value (N) is determined, which blackening value (N) represents a level of blackening of the interior of the lamp (1), and a recovery parameter (2, T) is calculate based on the blackening value (N). When the lamp power is increased above the saturation power level, the lamp (1) is driven according to the recovery parameter (2, T) for the duration of a specific recovery time. The invention further describes a driving arrangement (70, 70), and a projector system (10) comprising a high-pressure discharge lamp (1) and such a driving arrangement (70, 70).
摘要:
The present invention relates to a method of generating light with a predetermined chromaticity value of a color gamut by color mixing of the light emitted by a plurality of light sources, each of which emits light with a primary color, the light sources being capable of emitting light with at least three primary colors, wherein at least a first and a second light source are used to emit light of at least one primary color. The object to provide a simple method of generating light with a predetermined and constant chromaticity value of a color gamut by color mixing of the light emitted by a plurality of light sources, which can even be advantageously used in display applications sequentially displaying primary colors, is achieved in that said first and said second light source emit light with different peak and/or dominant wavelengths, the chromaticity of the primary color generated by color mixing of the light emitted from said first and said second light source being adjusted to a predetermined and constant chromaticity value by controlling the ratio of intensities of said first and said second light source, and said chromaticity value of said primary-color light generated by color mixing is used to generate light by color mixing with the light of other primary color light sources.
摘要:
The invention describes a method of driving a discharge lamp (1), wherein a value of pressure (Prlamp) in the lamp (1) is determined during operation of the lamp (1) at a dimmed power level, a correction factor (K, KR, KG, KB) is determined based on the dimmed power level pressure value (Prlamp), a required power value (Ptarget) for a requested light output level is calculated using the correction factor (K, KR, KG, KB), and the lamp (1) is driven according to the required power value (Ptarget). The invention further describes a method of driving a projector system (10, 10′). A driving unit (11, 11′) for driving a discharge lamp (1) in a projector system (10, 10′) is also described, as well as a projector system comprising a high-pressure discharge lamp (1) and a driving unit (11, 11′).