Abstract: An LED dimmer can be connected between a basic LED driver and an LED arrangement. The dimmer is able at least to receive a constant current from a constant current LED driver, and it then uses a boost converter to provide voltage boosting dependent on a required dimming level.

Abstract: An LED dimmer can be connected between a basic LED driver and an LED arrangement. The dimmer is able at least to receive a constant current from a constant current LED driver, and it then uses a boost converter to provide voltage boosting dependent on a required dimming level.

Abstract: The invention provides an illumination arrangement (1) for illuminating horticultural growths (100) with for instance LEDs as a light source. These LEDs are placed in a lighting unit (10). The lighting unit may especially have the ability to direct substantially all light from the light source (here the LEDs) to the horticultural growths (in the greenhouse). Additionally, a horticultural growth-recognition system (50) can be implemented in the illumination arrangement, so that the system can adapt for instance its beam (11) to the location of the horticultural growth(s) (in the case of growth or moving of plants, etc).

Abstract: The invention provides an illumination device (100) comprising a translucent exit window (200), one or more transmissive windows (300), arranged upstream from LED(s) and downstream from the translucent exit window (200), and one or more luminescent material layers (400), which may particularly be coated to the downstream and upstream faces of the transmissive windows (300).

Abstract: The invention provides an illumination device (10) with a light emitting diode (20), a transmissive support (50) comprising a luminescent material (51), and a translucent exit window (60). The ratio of the diffuser cavity cross section (212) and LED cavity cross section (211) is larger than (1). With the proposed illumination device (10), the lamp may in particular look white when it is in the off-state and illuminated with white light. Other advantages are that an intrinsically efficient system may be provided and that a warm white option may be provided.

Abstract: The invention provides a lighting device comprising at least one lamp and at least one OLED which are arranged to generate light, wherein the at least one OLED is arranged to transmit at least part of the light generated by the at least one lamp. The lighting device of the invention may advantageously provide the option of providing two types of light, namely, “normal” of the lamp, which can be used for e.g. illumination purposes, and OLED light of the OLED, which can be used for lumination purposes.

Abstract: The invention provides an illumination arrangement (1) for illuminating horticultural growths (100) with for instance LEDs as a light source. These LEDs are placed in a lighting unit (10). The lighting unit may especially have the ability to direct substantially all light from the light source (here the LEDs) to the horticultural growths (in the greenhouse). Additionally, a horticultural growth-recognition system (50) can be implemented in the illumination arrangement, so that the system can adapt for instance its beam (11) to the location of the horticultural growth(s) (in the case of growth or moving of plants, etc).

Abstract: The invention provides an illumination device (10) with a light emitting diode (20), a transmissive support (50) comprising a luminescent material (51), and a translucent exit window (60). The ratio of the diffuser cavity cross section (212) and LED cavity cross section (211) is larger than (1). With the proposed illumination device (10), the lamp may in particular look white when it is in the off-state and illuminated with white light. Other advantages are that an intrinsically efficient system may be provided and that a warm white option may be provided.

Abstract: The invention provides an illumination device (100) comprising a translucent exit window (200), one or more transmissive windows (300), arranged upstream from LED(s) and downstream from the translucent exit window (200), and one or more luminescent material layers (400), which may particularly be coated to the downstream and upstream faces of the transmissive windows (300).

Abstract: The invention provides an illumination device (10) with a light emitting diode (20), a transmissive support (50) comprising a luminescent material (51), and a translucent exit window (60). The luminescent material (51) LED (20) distance dLL is larger than 0 mm, and the luminescent material (51) exit window (60) distance dLW is also larger than 0 mm. With the pro-posed illumination device (10) the lamp may especially look white when it is in the off-state and illuminated with white light. Other advantages are that an intrinsically efficient system may be provided and that a warm white option may be provided.

Abstract: An illumination system comprises a gas discharge lamp (1) and at least one light-emitting diode (2). The illumination system according to the invention comprises means for reducing ultraviolet light emitted by the gas discharge lamp reaching the light-emitting diode. Preferably, the means for reducing ultraviolet light comprises an ultraviolet-absorbing or ultraviolet-reflecting shielding means ( ) provided between the gas discharge lamp and the light-emitting diode. Preferably, the gas-discharge lamp is a fluorescent lamp, for instance, a low-pressure mercury-vapor discharge lamp. Preferably, the illumination system is employed in an emergency lighting device or in a display device, in particular a liquid-crystal display (LCD) device. The illumination system according to the invention has a relatively long life.

Abstract: Disclosed is an artificial window (1) comprising a light box (10) having a rear wall (11) and a planar diffuser arrangement (14) in front of the rear wall (11). The artificial window further comprises at least one first light source (13) extending between the rear wall (11) and the diffuser (14); a window frame (20) in front of the diffuser (14); and drivers (15, 28) arranged for operating the light source (13) and electrically connected to the light source (13). The artificial window also comprises at least one additional light source (25) electrically connected to one of said drivers (28), which additional light source (25) radiates light in substantially one direction and is arranged to radiate light onto a portion of the front side of the diffuser arrangement (14) during operation.

Abstract: The invention relates to an illumination system (10, 12), a collimator (30, 32) for use in the illumination system and a spotlight. The illumination system comprises a light emitting diode (20), a collimator and a luminescent layer (40). The light emitting diode emits light via the luminescent layer and the collimator in a direction away from the illumination system. The collimator comprises a light input window (34) for receiving light from the light 5 emitting diode. The collimator further comprises a light exit window (36) for emitting a collimated beam of light. The light substantially progresses through the collimator via total internal reflection. The luminescent layer comprises luminescent material which converts at least part of the light emitted by the light emitting diode into light of a predefined color. The luminescent layer is applied to the light input window of the collimator.

Abstract: A light emitting device (100) is provided that comprises a longitudinally elongated housing (101) comprising a top wall (102) and opposing diffusing surface (103), and two mutually opposing reflective longitudinally elongated sidewalls (104) connecting said top wall (102) with said diffusing surface (103). An array of mutually spaced apart light emitting diodes (105) arranged is in said housing along the longitudinal extension thereof, and at least one of said sidewalls (104) is provided with an array of mutually spaced apart light redirecting means (106). The light redirecting means reflect light away from the LED that emitted the light, leading to a good mixing of light from the LEDs in the array.

Abstract: The invention provides a lighting device comprising at least one lamp and at least one OLED which are arranged to generate light, wherein the at least one OLED is arranged to transmit at least part of the light generated by the at least one lamp. The lighting device of the invention may advantageously provide the option of providing two types of light, namely, “normal” of the lamp, which can be used for e.g. illumination purposes, and OLED light of the OLED, which can be used for lumination purposes.

Abstract: Disclosed is an artificial window (1) comprising a light box (10) having a rear wall (11) and a planar diffuser arrangement (14) in front of the rear wall (11). The artificial window further comprises at least one first light source (13) extending between the rear wall (11) and the diffuser (14); a window frame (20) in front of the diffuser (14); and drivers (15, 28) arranged for operating the light source (13) and electrically connected to the light source (13). The artificial window also comprises at least one additional light source (25) electrically connected to one of said drivers (28), which additional light source (25) radiates light in substantially one direction and is arranged to radiate light onto a portion of the front side of the diffuser arrangement (14) during operation.

Abstract: A low-pressure mercury vapor discharge lamp is operable in a first mode of operation (“normal mode”) and a second mode of operation (“emergency operation”). The discharge lamp comprises a discharge vessel (10) enclosing a discharge space (13) provided with a filling of mercury and an inert gas. The discharge vessel comprises electrodes (5;6) for maintaining a discharge in the discharge space while the discharge lamp operates in the first mode of operation. According to the invention, at least one of the electrodes is operated on a DC or AC power supply for drawing a discharge current (D1;D2) over the electrode while the discharge lamp operates in the second mode of operation. Preferably, both electrodes operate on a DC or AC power supply, preferably a battery, while the discharge lamp operates in the second mode of operation. The low-pressure mercury vapor discharge lamps operated according to the invention have a relatively long life.

Abstract: An area light source (1) comprising a first light source (2) emitting light (L2) in a first wavelength range, and a light-transparent carrier screen (4) coated with a phosphorous layer (5) is disclosed. The area light source is characterised in that it comprises at least one additional light source (3) projecting light L3 in a second wavelength range, differing from said first wavelength range onto the carrier screen (4), said projected light L3 being capable of exciting the phosphorous layer (5).

Abstract: The artificial window (1) for use in apartments which lack a window through which day light may enter, has a light box (10) in which three sets of color lamps as light sources (13R,13G,13B) are mounted behind a diffuser (14). A window frame (20) is present in front of the diffuser (14) and a transparent plate (21) in the window frame (20), remote from the diffuser (14). Drivers (15) are present to start, to operate and to dim the light sources (13) thereby allowing to imitate natural light at different seasonal and time conditions. A number of features are described that further enhance the appearance of a real window.

Abstract: The lamp life of a gas discharge lamp (6) depends inter alia on the deterioration of an electrode of the lamp during operation. The deterioration depends on an operating temperature of the electrode. A method according to the present invention for controlling the lamp life includes controlling the electrode temperature during operation by generating a temperature signal (12) representing the electrode temperature and providing said signal to a lamp driver circuit (4) operating said lamp. The lamp driver circuit controls an operating signal (10) supplied to the lamp (6) in order to control the electrode temperature to lie within a predetermined temperature range, thereby minimizing damage to the electrode during operation.