DE10216645B4 - Luminaire with variable light color - Google Patents

Abstract

Lighting arrangement, in particular luminaire, which has light sources which emit light with different spectral properties, and a device for mixing light with different spectral properties of different light sources, wherein at least one of the light sources is a light-emitting diode (12, 34) or a group of light-emitting diodes (12 , 34) which emit colored light, and at least one further light source is a lamp (11, 32), these light sources being individually controllable and light of the light emitting diode or of the light emitting diodes and this lamp (11, 32) being mixed by the mixing device , characterized in that a control device is provided which controls or controls the light sources according to a predetermined scheme, and thereby the light sources are controlled by the control device over a predetermined illumination period according to a predetermined program so that illuminance and light color above the Change the lighting period, whereby at the beginning and at the end of this period, the control is set to a value between 250 and 550 lx and within this period exactly one period of time ...

Description

The invention relates to a lighting arrangement, in particular a luminaire, which has light sources which emit light with different spectral properties, and comprises means for mixing light with different spectral characteristics of different light sources.

Out EP 0 545 474 A1 Such a luminaire is known, with the help of which natural daylight is to be simulated. In this lamp lamps with different spectral properties are arranged so that they radiate their light on a reflective screen, which reflects the light incident on him to a transparent screen. As a result, the light of the lamps is mixed, so that the spectral composition of the emerging from the lamp light can be changed by different control of the lamps. It is proposed in this document to control the lamps by a computerized unit so that for a given latitude and a certain season, the light conditions, ie intensity, color and direction of the light, are simulated. In this way, physiological disorders in people who are exposed to artificial light for a long time to be counteracted.

WO 01/88434 A1 discloses, also for medical purposes, a lighting device with lamps with different spectral properties, which are controlled by a computer. The intensity and spectral composition of the light emitted by the illuminator is detected by sensors whose signals are evaluated by the computer and used to drive the lamps. The computer controls lighting according to pre-entered illumination patterns corresponding to a particular date and location on the earth. The sensors can also be used to calibrate control signals for lamps to specific illumination levels.

DE 296 20 583 U1 discloses a lamp with an incandescent lamp and a rotationally symmetrical reflector, wherein at the bottom of this reflector light-emitting diodes are arranged which emit light in different colors. The reflector can be adjusted by an electric motor in the axial direction relative to the incandescent lamp and its holder. Furthermore, a switch is provided, with which the hue of the radiated light from the lamp can be adjusted.

In the prior art lamps with different spectral characteristics were used. This allowed the required illuminance levels to be achieved. However, the possibilities of designing the spectral distribution were limited.

It is the object of the invention to provide a lighting arrangement of the type mentioned above, which allows a design of the spectral properties to a greater extent.

According to the invention this object is achieved by a lighting arrangement according to claim 1, wherein it can be provided that at least one of the light sources is an LED or a group of LEDs that emit colored light and at least one further light source is provided which emits white light, said These light sources are individually controlled. The invention can provide, in particular, that the light-emitting diode or light-emitting diodes and the further light source can be switched on and off independently of one another and / or their light output can each be set independently of one another. In this way it is possible to generate light with different hue by switching on and off or individual setting of the colored light-emitting diodes.

The invention may provide that the lighting arrangement comprises a plurality of lamps which emit light with different spectral distribution. In this embodiment, by turning on or off the light emitting diodes, it is possible to adjust the spectral composition of the emitted light regardless of the spectral characteristics of the lamps. The lamps can be, for example, high-pressure lamps, compact fluorescent lamps, incandescent lamps, halogen incandescent lamps or high-pressure lamps.

The invention may provide that one or more of the light sources are dimmable.

The mixing device according to the invention can be located within a luminaire. In this way, light emerges with a uniform light color and color shadows are avoided.

The invention may provide that a plurality of light sources are provided, each of which emits colored light which can be mixed by means of the mixing device additively to white light. Optionally, the light source with white light can be omitted and replaced by a group of light sources, in particular lamps, which emit colored light and can produce white light by mixing their light together.

The invention is based on the finding that for changing the spectral properties even when specifying a comparatively high Illuminance no particularly strong light sources are required. Therefore, faint light sources, such as light emitting diodes, can be used to produce the necessary color blends. Light-emitting diodes are particularly easy to control and group in groups for additive color mixing.

The mixing device may be or comprise a light-reflecting or a refractive device, which superimposes the light from different light sources on each other. For example, the mixing device may consist of a diffusely reflecting reflector onto which the lamps emit light. The mixing device may also consist of or comprise a lens or a prism. In particular, a refractive beam splitter device or a semitransparent mirror can be used which, conversely, d. H. not in the sense of a beam splitting, but in the sense of beam merging, operated.

The invention can also provide that the mixing device comprises a cavity with at least partially reflecting walls, is irradiated in the light of different light sources and is reflected one or more times on the reflective walls, so that superimpose the different light components.

In particular, the invention may provide that the mixing device comprises a hollow light guide having a cavity with at least partially reflecting walls and at least one light exit surface.

At the light exit surface, a light-guiding structure, for example a prismatic structure, may be provided. However, it can also be provided a simple glass or a diffusely diffusing disc.

According to a second aspect of the invention, there is provided a lighting arrangement, in particular a luminaire, which has light sources which emit light with different spectral properties, and means for mixing light with different spectral characteristics from different light sources, characterized in that the mixing device comprises a photoconductive element, in particular a photoconductive plate, into which light is coupled by different lamps having different spectral characteristics and from which mixed light z. B. is decoupled by means of a prismatic structure at the light exit surface. The light-conducting element may in particular be a hollow or full-light conductor.

In particular, when the photoconductive element is a photoconductive plate, in this way a flat luminaire with the properties according to the invention can be realized.

According to a third aspect of the invention there is provided a lighting arrangement, in particular a luminaire, which comprises light sources which emit light with different spectral properties, and means for mixing light with different spectral characteristics from different light sources, characterized in that the mixing device comprises a hollow light guide having a cavity with at least partially reflecting walls and at least one light exit surface on which a refractive structure, in particular a prism structure is provided, which causes the majority of the luminous flux in a predetermined range of angles to the vertical Light exit surface is discharged, z. B. with angles smaller than 60 °, while no or a smaller part of the luminous flux is discharged into the remaining space areas.

In particular, the invention can provide that a shield is produced by the refractive structure.

According to the invention it can be provided that at the beginning and towards the end of this period, the control is at a value between 250 and 550 lx and within this period exactly one period is provided in which the illuminance is controlled to a maximum value by a factor of 1 , 2 to 8 is above the start or end value of the illuminance.

The invention may provide that changes the light color with the illuminance. It can also be provided that the light color is controlled independently of the illuminance according to a separate program.

It can be provided that the beginning and end of this period are fixed times of the daily routine. If the lighting device is put into operation after the beginning of this period, the activation is not made to the initial value, but to the value corresponding to the time of switching on within the lighting period.

The change in illuminance is carried out continuously and as slowly as possible according to an embodiment of the invention. According to another embodiment, however, it may be provided that at certain times, for. B. at lunchtime or in the evening or at break times, abrupt Changes in illuminance and / or light color take place.

For certain applications, luminance, rather than illuminance, can be used as a reference for control.

According to the invention, the light color can be in a range from 2000 K to 7000 K or adjusted to a value in this range, the color rendering index R _a preferably being in a range between 40 and 100, preferably between 60 and 1000 and particularly preferably between 80 and 100, lies. Preferably, the control is carried out at the beginning and towards the end of the lighting period to a warmer light color than at a period between the beginning and end of the lighting period, in particular as in the period of the maximum of the illuminance.

The invention can provide that the illuminance, luminance and / or light color are detected by one or more sensors and the output signal of these sensors is used to control the illuminance, luminance and / or light color. The sensors can be installed in a luminaire.

In a lighting arrangement according to the preamble of claim 1 can be inventively provided that different room zones are illuminated according to different programs.

In a lighting arrangement according to the preamble of claim 1 can be inventively provided that at least a portion of the light of the light sources is directed over a reflective surface.

According to the invention it can be provided that the illumination arrangement, in particular a luminaire according to the invention, emits substantially white light. It can be provided in particular that at least one lamp of the illumination arrangement emits white light and the light mixed by the illumination arrangement is also white, but has a different spectral distribution than the white light emitted by the lamp. In this case, the lighting arrangement, in particular a luminaire, be designed so that it basically emits only white light due to the dimensioning of the light sources and the proposed control and regulation options. In particular, it can be provided that the colored light emitted and admixed by the light-emitting diodes according to the invention has a proportion of not more than 40%, preferably not more than 20%, of the total light emitted.

In this way, white light with a spectrum for different color temperatures can be simulated or generated. In general, one will try to set the light components of the colored LEDs so that the proportion of one or more spectral components, which corresponds to the color of a light source, in particular a light emitting colored light, after mixing, ie including the color components of the Spectrum of the output of a lamp white light, the value of this spectral component of white light at a certain color temperature, which may be in a range of 2000 to 7000 K. According to the invention, it can also be provided that the ratio of the different color components to one another is adjusted in accordance with the spectral distribution of white light at a specific color temperature by appropriate adjustment of the light-emitting diodes. A precise simulation of the spectral distribution is not absolutely necessary. According to the invention it can be provided that the corresponding spectral component for a particular color or the ratio of spectral components deviates by not more than 30%, preferably not more than 10% from the corresponding value of the spectral distribution of white light at the given color temperature.

To produce mixed light with certain spectral properties, in particular of white light with the previously described spectral properties, it can be provided that the respective light output of the individual light sources for generating this spectral distribution is fixed, that it is manually adjustable or that they automatically according to a certain program is set.

According to a further aspect of the invention it can be provided that the various light sources are individually adjustable, but are collectively controlled by a control device, wherein at least the light output of one of the light sources is not an input parameter of the control device, but from a functional dependence on such an input parameter results.

In particular, the luminaire according to the invention can be a secondary luminaire in which light from a plurality of light sources is emitted via a reflector which mixes this light. Similarly, indirect lights can be used, which radiate the light of different light sources to the ceiling or on a wall at which the light is reflected and mixed with it. The indirect component may be 10% to 75% according to one embodiment of the invention.

A luminaire according to the invention can also be a trough luminaire or a luminaire with a grid.

Further features and advantages of the invention will become apparent from the following description of an embodiment of the invention with reference to the accompanying drawings.

1 schematically shows a first embodiment of the invention in a schematic sectional view.

2 shows a graph that shows the regulated illuminance during the day.

3 schematically shows a second embodiment of the invention in a schematic sectional view.

4 shows schematically a control scheme for the illuminance.

1 schematically shows an embodiment of a lamp according to the invention with a hollow light guide, which generally with 1 is designated. The light pipe 1 has a cavity 3 on, by reflecting walls, of which only the roof wall 5 is shown, and prism plates 7 and 9 is limited. On the open sides of the waveguide light from two lamps 11 with the light color 31-830 according to the nomenclature of the company Osram (equivalent to 3000 K) directly or by reflection at Einkoppelreflektoren 13 coupled. The light is possibly after one or more reflections on walls of the cavity 3 , about the prism plates 7 and 9 decoupled. The prism plates are as in the European patent application EP 1 111 298 A1 formed so that it is a shield in planes parallel and perpendicular to the axis of the lamps 11 produce. On the roof wall 5 are three light emitting diodes or groups of light emitting diodes 15 arranged, which emit red, blue and green light. The lamps 11 and the light emitting diodes 15 are each separately controllable. The light-emitting diodes 15 can, but do not have to represent a complete color system with which all light colors can be produced by additive color mixing. It can also be provided that the light-emitting diodes 15 or the group of LEDs only light with two different colors or only light of a color, eg. B. red or blue.

The lamps 11 and the light emitting diodes 12 are controlled by an automatic control device (not shown) according to a scheme for the illuminance, which in 2 is shown. The LEDs are controlled differently according to the time of day. In the early and late hours of the day, colored light enters the cavity through the LEDs 3 irradiated, which is in the cavity 3 encircling white light of the lamps 11 mixes, so that overall a warmer hue is created. Thus, a spectral distribution can be generated, the distribution at a lower color temperature, z. B. 2700 K, is approximated. At noon, the LEDs are moved back, so that essentially the light of the lamps 11 is emitted from the lamp. Optionally, by mixing in blue light of a light emitting diode and a colder hue can be generated or it can be generated by suitable control of the LEDs, a spectral distribution, the distribution at a higher color temperature, z. B. 4000 K, is approximated.

In the scheme of 2 can also be provided that one of the two lamps 11 at the beginning and towards the end of the lighting period is not in operation and is switched on only in times of high illuminance.

In a modification of the embodiment described above can also be provided that the two lamps 11 have different spectral properties. For example, one of the lamps could have the light color 41-827 (according to Osram, equivalent to 2700 K) and one of the lamps the light color 21-840 (according to Osram, equivalent to 4000 K). At the beginning of the lighting period, first the lamp 41-827 is operated and at noon, the lamp 21-840 is switched on, the lamp 21-840, depending on the desired illuminance and spectral distribution, continue to operate or can be turned off. The transition to the operation of the lamp 21-840 can by appropriate control of the LEDs 15 and suitable dimming of the two lamps 11 be evenly adjusted so that a viewer perceives substantially a continuous change in the lighting conditions.

A modification of this embodiment is in 3 shown. The same components are provided with the same reference numerals. Here are the LEDs 15 attached to the sides of the light pipe while the lamp 11 from above through a central opening in the cavity 3 is introduced. To improve the light mixture is the lamp 11 down through a reflector 20 covered, the light incident on him to the roof wall 5 reflected. If necessary, this reflector can also be omitted.

4 shows an embodiment of a lamp according to the invention with a full light guide in the form of a photoconductive plate 30 , in which from both sides light from fluorescent lamps 32 and light-emitting diodes 34 is coupled. The light enters a light emission surface provided with a prismatic structure 36 out. The lamps 32 and light-emitting diodes 34 are surrounded by a Einkoppelreflektor (not shown), which covers them simultaneously to the light exit side. Because the light in the plate 30 is reflected internally to a large extent before the exit, a light mixture takes place. The fluorescent lamps 32 and the light emitting diodes 34 can be operated as described above. Again, several fluorescent lamps with different spectral properties can be used.

Numerous modifications of the previously described embodiments are possible. For example, the lamp may be a circular lamp. A changing light color and illuminance can also be generated solely by mixing the light of colored light sources.

LIST OF REFERENCE NUMBERS

1

Light Pipes

3

cavity

5

roof wall

7, 9

prism plates

11

lamps

12

LEDs

13

Einkoppelreflektoren

15

LEDs

20

reflector

30

plate

32

fluorescent lamps

34

LEDs

36

Light-emitting surface

Claims (21)

Lighting arrangement, in particular luminaire, which has light sources which emit light with different spectral properties, and a device for mixing light with different spectral properties of different light sources, wherein at least one of the light sources is a light-emitting diode ( 12 . 34 ) or a group of light emitting diodes ( 12 . 34 ), which emit colored light, and at least one further light source emits a lamp ( 11 . 32 ), wherein these light sources are individually controllable and light of the light-emitting diode or the light-emitting diodes and this lamp ( 11 . 32 ) is mixed by the mixing device, characterized in that a control device is provided which controls or controls the light sources according to a predetermined scheme, and the light sources are controlled by the control device over a predetermined illumination period according to a predetermined program so that illuminance and Change color of light over the illumination period, at the beginning and towards the end of this period, the control is set to a value between 250 and 550 lx and within this period exactly one period is provided, in which the illuminance is driven to a maximum value by a factor of 1.1 to 30 above the starting and / or end value of the illuminance. Lighting arrangement according to claim 1, characterized in that the lamp ( 11 . 32 ) gives off white light. Lighting arrangement according to one of claims 1 or 2, characterized in that the lighting arrangement comprises a plurality of lamps ( 11 . 32 ), which emit light with different spectral distribution. Lighting arrangement according to one of claims 1 to 3, characterized in that one or more of the light sources are dimmable. Lighting arrangement according to one of claims 1 to 4, characterized in that a plurality of light sources are provided, each emit colored light, which can be mixed by means of the mixing device additively to white light. Lighting arrangement according to one of claims 1 to 5, characterized in that the mixing device comprises a light guide. Lighting arrangement according to claim 6, characterized in that the mixing device is a full light guide, in particular a photoconductive plate ( 30 ), in which light from different lamps ( 11 . 32 ) is coupled with different spectral characteristics and from which color mixed light is coupled via a light output device. Lighting arrangement according to claim 6, characterized in that the mixing device is a hollow light guide ( 1 ) comprising a cavity ( 3 ) with at least partially reflective walls and at least one light exit surface ( 36 ), on which a refractive structure, in particular a prismatic structure is provided, which causes the predominant part of the luminous flux in a predetermined range of angles to the perpendicular to the light exit surface (FIG. 36 ) is discharged while no or a smaller part of the luminous flux is discharged into the remaining space areas. Lighting arrangement according to claim 8, characterized in that the refractive structure at angles above a critical angle to a perpendicular to the light exit surface ( 36 ) creates a shield. Lighting arrangement according to one of claims 1 to 9, characterized by a control device which adjusts the light output of the light sources in response to input parameters, wherein the light output of at least one light source by a functional dependence on the value of at least one setting variable, which is different from the light output of this light source , is fixed. Lighting arrangement according to claim 10, characterized in that the control device is such that the light color and the illuminance can be set independently. Lighting arrangement according to claim 1, characterized in that the light color is controlled independently of the illuminance according to a separate program. Lighting arrangement according to one of claims 1 to 12, characterized in that the light color is adjusted or adjustable by the control device so that white light can be delivered with different color components. Lighting arrangement according to one of Claims 1 to 13, characterized in that the light color is adjusted or adjustable by the control device in such a way that white light is emitted, the proportion of at least one spectral range in the mixed light emitted by the illumination arrangement, which corresponds to the color of the a light emitting diode or a group of light emitting diodes corresponds to the proportion of this spectral range in a spectrum for a color temperature which is in the range of 2000 K to 7000 K. Lighting arrangement according to one of claims 1 to 14, characterized in that the illuminance, luminance and / or light color are detected by one or more sensors and the output signal of these sensors for controlling the illuminance, luminance and / or light color is used. Lighting arrangement according to one of claims 1 to 15, characterized in that different room zones are illuminated according to different programs. Lighting arrangement according to one of claims 1 to 16, characterized in that the light sources are arranged so that the mixed light from the lamp ( 11 . 32 ) and the light-emitting diode or the light-emitting diodes ( 12 . 34 ) is white light and has a spectral distribution different from the spectral distribution of the light emitted by the respective light sources ( 11 . 12 . 32 . 34 ) is delivered. Lighting arrangement according to claim 17, characterized in that the light components of the lamp ( 11 . 32 ) and the light emitting diode (s) ( 12 . 34 ) mixed light is white light, wherein the spectral component of a light color emitted by a light-emitting diode or a group of light-emitting diodes in the spectral distribution of the mixed light corresponds to a color temperature which is in a range from 2000 K to 7000 K. Method for operating a lighting arrangement according to one of Claims 1 to 18, characterized in that the light output of the light-emitting diode ( 12 . 34 ) or the light emitting diodes and the lamp ( 11 . 32 ) is set so that the mixed light of the light emitting diode or the light emitting diodes and the lamp is white light. A method according to claim 19, characterized in that the light output is adjusted so that a spectral component of the mixed light corresponding to the color of the light emitted from a light emitting diode corresponds to the proportion of that color in a spectral distribution for a color temperature falling within a range of 2000 K to 7000 K is. Method according to one of claims 19 or 20, characterized in that the light sources are operated so that the proportion of the light output of the light-emitting diodes is between 1% and 40% of the light output of the lamp.

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