Abstract: The invention provides a luminaire comprising a luminaire housing accommodating a driver housing assembly, the driver housing assembly comprising a driver housing and a cable; the driver housing (10) comprising: a terminal block (11) for connecting a cable (30) to a driver; a compartment (12) for receiving the cable (30); a first housing wall (14) adjacent to a second housing wall (24), wherein the first housing wall (14) comprises a first entrance (15) arranged for receiving the cable (30) and the second housing wall (24) comprises a second entrance (25) arranged for receiving the cable (30), and wherein said first housing wall (14) and said second housing wall (24) enclose a part of the compartment (12); a lid (13) for closing the compartment (12) and for in closed position confining the cable (30) in the first entrance (15) or the second entrance (25); wherein the cable is connected to the terminal block, and wherein the cable is received by the driver housing via either the first entrance or the second en

Abstract: The invention provides a luminaire comprising a luminaire housing accommodating a driver housing assembly, the driver housing assembly comprising a driver housing and a cable; the driver housing (10) comprising: a terminal block (11) for connecting a cable (30) to a driver; a compartment (12) for receiving the cable (30); a first housing wall (14) adjacent to a second housing wall (24), wherein the first housing wall (14) comprises a first entrance (15) arranged for receiving the cable (30) and the second housing wall (24) comprises a second entrance (25) arranged for receiving the cable (30), and wherein said first housing wall (14) and said second housing wall (24) enclose a part of the compartment (12); a lid (13) for closing the compartment (12) and for in closed position confining the cable (30) in the first entrance (15) or the second entrance (25); wherein the cable is connected to the terminal block, and wherein the cable is received by the driver housing via either the first entrance or the second en

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: An ignition circuit for igniting a gas discharge lamp generates a high voltage gas breakdown pulse by building up a current through a primary winding of a transformer. After a predetermined period and thus when a predetermined current flows through the primary winding, a capacitance is switched in series with said primary winding, thereby generating said high voltage gas breakdown pulse in a secondary winding of said transformer. After generating the high voltage pulse, the capacitance is short-circuited in order to preserve energy in the primary winding. The preserved energy is employed to build up energy again for a next high voltage pulse in a short time. At a high repetition rate and high voltage of the generated pulses, the ignition circuit according to the present invention is also suitable for driving the gas discharge lamp during a take-over period following the gas breakdown of the lamp for heating the lamp electrodes.

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: 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 invention relates to local luminaire control in an area based lighting control system. A basic idea of this invention is to use a soft switch assigned to one or more luminaries of an area based lighting control system to locally control the luminaire/ies, wherein the soft switch is adapted for generating an appropriate signal for the area based lighting control system, that puts the luminaire/ies in the desired state.

Abstract: 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.

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: 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 (O), 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 (O) 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.

Abstract: A method and a circuit arrangement (1) for operating a high intensity discharge lamp (2), which is supplied by direct current (DC) supply lines (4, 6), comprising a transformer (40), of which a primary winding (42) is connected in series with an inductor (46) and a capacitor (48) to the DC supply lines (4, 6), a secondary winding (44) of the transformer is connected in series with the lamp, a switch (52) is connected in parallel to the capacitor (48), and a control circuit (56) is connected to the switch (52), whereby the control circuit (56) controls the switch to conduct upon detecting a zero crossing of a voltage (Vsw) at the switch, and the control circuit controls the switch to not conduct upon detecting a value of a current through the switch which is greater than a reference value.

Abstract: A driver for HID lamps includes four switches and generates a constant DC-current that is commutated at a low frequency. The driver includes a filter capacitor. The occurrence of peak currents due to the charging or discharging of the filter capacitor is prevented by driving one of the switches at a high frequency immediately after commutation.

Abstract: An ignition circuit for igniting a gas discharge lamp generates a high voltage gas breakdown pulse by building up a current through a primary winding of a transformer. After a predetermined period and thus when a predetermined current flows through the primary winding, a capacitance is switched in series with said primary winding, thereby generating said high voltage gas breakdown pulse in a secondary winding of said transformer. After generating the high voltage pulse, the capacitance is short-circuited in order to preserve energy in the primary winding. The preserved energy is employed to build up energy again for a next high voltage pulse in a short time. At a high repetition rate and high voltage of the generated pulses, the ignition circuit according to the present invention is also suitable for driving the gas discharge lamp during a take-over period following the gas breakdown of the lamp for heating the lamp electrodes.

Abstract: A fluorescent lamp preheating circuit heats electrodes prior to lamp ignition while utilizing a sense resistor to detect and correct short-circuit conditions caused by improper wiring. The circuit uses few components, each of which is independent of parameters such as switching frequency, duty-cycle, and filament resistance, and is therefore compact, cost-effective, and efficient. The preheating circuit can be switched off when the electrodes are warmed sufficiently in order to conserve energy and prevent thermal overload, or when short-circuit conditions are encountered.

Abstract: A fluorescent lamp preheating circuit heats electrodes prior to lamp ignition while utilizing a sense resistor to detect and correct short-circuit conditions caused by improper wiring. The circuit uses few components, each of which is independent of parameters such as switching frequency, duty-cycle, and filament resistance, and is therefore compact, cost-effective, and efficient. The preheating circuit can be switched off when the electrodes are warmed sufficiently in order to conserve energy and prevent thermal overload, or when short-circuit conditions are encountered.

Abstract: In an upconverter operating in the transient mode, an offset signal is added to the signal at the current sensing pin of the control IC. The upconverter generates a comparatively low THD even if the supply voltage and/or the power supplied by the upconverter are varied over a wide range.

Abstract: In an upconverter operating in the transient mode, an offset signal is added to the signal at the current sensing pin of the control IC. The upconverter generates a comparatively low THD even if the supply voltage and/or the power supplied by the upconverter are varied over a wide range.