EP2981759B1 - Led system, light equipped with such a system and method of influencing wavelenght spectrum of a lighting system - Google Patents

Description

The invention relates to an LED module, a luminaire with such an LED module and a method for influencing a light spectrum.

A light spectrum or color spectrum is a part of the electromagnetic spectrum that can be perceived by the human eye without any further technical aids. Such a light spectrum is composed of emitted or reflected spectral colors of a corresponding light source or of light sources. As a rule, such a light source emits light with a specific frequency spectrum or corresponding spectral distribution, the corresponding frequencies of the light determining its color. Corresponding artificial light sources differ in color, brightness, etc., with a visible portion of the light spectrum having a wavelength in the range of about 380 to 780 nm and frequencies in the range of about 3.8 x 10 ¹⁴ to 7.9 x 10 ¹⁴ Hz, respectively , Without optical aids corresponding color components of the light spectrum are indistinguishable, with many light sources usually deliver a light spectrum as a combination of different individual colors that lead in the eye of a viewer to a total color impression or a mixed color. Such a light color corresponds to a color impression of the light, which comes directly from a corresponding self-luminous light source. The light color depends on the spectral composition of this radiation.

With regard to the light color, even when the light is "white" in itself, different subdivisions result, such as warm white, neutral white, daylight white and the like. Each of these corresponding whites is assigned a different effect on humans. Other light colors also discuss psychological effects on the observer. In addition, it should be noted in connection with other species that they usually have different sensitivities for certain spectral ranges in comparison to humans.

In connection with the light color, another parameter has to be considered, which is called the color rendering index.

This index is a photometric quantity that describes the quality of the color reproduction of light sources of the same correlated color temperature. As a reference for judging the reproduction quality, for example, up to a color temperature of 5000 K, the light emitted from a black body of a corresponding color temperature serves. The color rendering index is "100" when a corresponding artificial light source perfectly reproduces the spectrum of a blackbody having the same color temperature in the range of visible wavelengths.

An example of recently used light sources are LED light sources that consume little energy while having a long life. Corresponding LEDs usually generate a substantially monochromatic radiation, wherein the hue of the corresponding LED light is dominated by the dominant wavelength of the corresponding radiation. There are LEDs in different colors, such as red, orange, yellow, green or even blue. Also known are white LEDs, which typically use a conversion layer to actually convert blue light generated by the LED into white light. Such conversion layers are also known from fluorescent lamps.

A corresponding emission spectrum of an LED is relatively narrow-band, wherein, see the preceding statements, a corresponding dominant wavelength and thus the color of the light is dependent on the materials used to produce a corresponding semiconductor crystal of the LED. In general, LED light does not contain UV or IR radiation.

LEDs are preferably manufactured as LED modules. These are very flat and have a plurality of LEDs on a support, wherein such a support can also be flexible. The carrier may be a printed circuit board equipped with appropriate wiring and / or with electronic components for actuating the LEDs.

In the DE 10 2010 033 141 describes a lamp in which the light generated is influenced in spectral sensitivities of different species. As the light source of such a lamp, for example, a previously described LED module or more of these is used. In order to influence the corresponding light, a filter device is used which at least partially filters out one or more specific spectral regions of the emitted light. This will be Filtered out or at least attenuated spectral regions in which certain species and in particular animals have a higher sensitivity and in which spectral regions these species may be adversely affected. It is of course also conceivable that the spectral range of the light to be emitted is selected so that it positively influences one or more species. The corresponding lamp can be used for example for street lighting or for lighting sidewalks or even in a lighting in parks or the like.

It is of course also possible to perform a corresponding filtering for light in rooms in which certain spectral ranges of the emitted light could trigger reactions or the like, see for example biological, chemical or physical applications.

In the DE 10 2010 033 141 a corresponding filter device in the luminaire housing or in the region of a light exit opening of the lamp housing is arranged. D. h., The influence of the corresponding light spectrum or color spectrum of the light source is effected by an additional device. Disadvantage of such a device is that a portion of the light is retained, and therefore the effectiveness of the entire lighting system is reduced. In other words, when filtering, the radiant power or radiant intensity decreases compared to a luminaire without filtering with the same power supply. US 2010/020536 A1 describes LED subgroups as part of a general LED arrangement. The corresponding overall system is used to illuminate plants to improve their growth. Each LED array has two or more types of LEDs. The number of LEDs of each LED subassembly may be changed or, overall, the current of a subarray is adjusted.

DE 10 2007 026867 A1 describes a lamp with different LED rows different colors ner. Each row of LEDs of the same color is controlled overall.

DE 10 2005 061204 A1 discloses sub-modules with LEDs of the same color. These are all controlled together and it is still possible, if necessary, to add a white LED.

DE 10 2004 006005 A1 describes an emergency lighting. A color rendering index should be adjusted if necessary by adding a white LED. LEDs of the same type are optimally controlled overall. US 2009/323334 A1 describes a linear LED arrangement. This serves to generate white light.

The invention is therefore based on the object to allow influencing the light or color spectrum in a simple manner, without major structural changes or additional installations are to be made in a corresponding lamp, with only a small number of lights is used.

The object is achieved by the features of claim 1. This applies analogously to the features of the method claim and a corresponding lamp with such an LED module.

According to the invention, the LED module is distinguished by the fact that, given a particular number and color of the LEDs, these emit a total light emission spectrum composed of individual light emission spectra of each LED, wherein the LEDs can be varied relative to one another in the intensities of their individual light emission spectra. That is, there will be certain numbers of red, green, blue, and / or yellow

LEDs are used on the LED module, each of these LEDs is adjustable in intensity, so that by varying the individual intensities of the corresponding light emission spectra and then superimposing these spectra results in the total light emission spectrum.

The corresponding luminaire has at least one LED module, and several such modules can be used. Furthermore, such a luminaire has at least one luminaire housing, a light exit opening formed in the luminaire housing, and a glare limitation device. By this, the exit of the light from the light exit opening of the lamp is limited to a certain range, for example, to reduce a glare of the lamp. Each LED is configured to emit substantially monochromatic light radiation. The corresponding individual light emission spectrum of each LED is known or at least detectable beforehand. LEDs with different monochromatic light radiation are then arranged together on the corresponding LED carrier and by superposition of the individual light emission spectra with the respective intensity to form a total light emission spectrum, the correspondingly desired light spectrum of the light source results. LEDs with the same monochromatic light radiation are each arranged on a submodule of the LED module. This means that LEDs with the same monochromatic light radiation are arranged together and, depending on the required number of corresponding LEDs, submodules are combined with such LEDs. The LEDs are arranged relatively close to each other, so that even at a small distance and optionally with the aid of appropriate reflection devices no punctiform light sources are more recognizable, but only the superposition of all individual light emission spectra to the total light emission spectrum for a viewer is recognizable. Each LED is individually controllable, d. H. in particular supplied with appropriate voltage or current. As a result, all the LEDs are reliably controlled and the corresponding emitted individual light emission spectrum is well reproducible with its corresponding intensity and in addition of all individual emission spectra, the total light emission light spectrum can be produced safely. It is also possible that all the same color LEDs are supplied with selected voltage or current accordingly.

According to the method, the corresponding light color of the light emitted by the light is influenced in such a way that a plurality of LEDs are arranged at least in a row and / or a column on a corresponding LED module. Each of the LEDs emits light according to a single light emission spectrum with appropriately adjusted intensity, the individual spectra of all the LEDs superimposing on a total light emission spectrum giving the light spectrum of the light source of the corresponding luminaire.

By using sub-modules, it is possible in a simple manner to combine LEDs with the corresponding light color as required and also to select them in terms of their number. For example, if more yellow LEDs are needed, more sub-modules will be added with those yellow LEDs. This applies analogously for differently colored LEDs.

However, there is also the possibility that LEDs with different monochromatic light radiation are arranged on a submodule of the LED module. That is, already on a sub-module, a desired light color is provided by combining differently colored LEDs of corresponding intensity on this sub-module. A number of such sub-modules can then be used together as an LED module and these give the desired total light emission spectrum.

When the LEDs are arranged, they are arranged along at least one row and / or one column on the corresponding LED carrier. As already stated in the introduction, such a carrier can be a corresponding printed circuit board for supplying the LEDs, for the corresponding wiring for required connections and also for arranging further electronic or electrical devices.

In the case of such a row and / or column arrangement, it is possible that, for example, only LEDs of the same color along a row or corresponding LEDs along a column are arranged. It is also conceivable that differently colored LEDs are provided in each row and / or column.

To optionally increase the color rendering index of the corresponding light source, the monochromatic LEDs may be associated with white LEDs. The number of white LEDs, for example, can be determined by the color rendering index to reach a value of 100 or at least close to 100.

In order to be able to easily change the overall light emission spectrum, it is conceivable that modules and / or sub-modules are arranged interchangeably in the luminaire. This can apply analogously to the corresponding LED carrier.

In order to possibly change the light color of the light source at short notice, it may also prove advantageous if the submodules can be controlled individually. This means that, for example, a submodule with only yellow LEDs is only switched on if the total light emission spectrum is to be changed accordingly by connecting these yellow LEDs. This applies analogously to differently colored LEDs, white LEDs and the like.

As already explained above, such an adaptation of the total light emission spectrum can be carried out in particular with regard to certain species which have a higher sensitivity in a spectral range. It is also conceivable that the adaptation of the total light emission spectrum with respect to more than one species takes place if they have the same sensitivity in a specific spectral range or at least in closely adjacent spectral ranges. It is also possible according to the invention to amplify a specific spectral range by connecting LEDs with respect to light output, if the zuzuschaltenden LEDs light up, for example, in this spectral range. Thereby, certain advantageous effects in the specific spectral range can be increased.

There is also the possibility that the light spectrum is changed not only by connecting corresponding LEDs, but also by deliberately switching off certain LEDs with a known individual light emission spectrum. Also by such switching off of LEDs and optionally varying the intensities of the remaining LED's results in a change in the total light emission spectrum, which may have the desired effect.

In the following, advantageous embodiments will be described with reference to the accompanying figures in the drawing.

Figur 1

eine perspektivische Ansicht von unten auf eine Leuchte mit LED-Modulen;

Figur 2

eine vergrößerte Darstellung eines Ausführungsbeispiels eines LED-Moduls;

Figur 3

eine vergrößerte Darstellung eines weiteren Ausführungsbeispiels eines LED-Moduls;

Figur 4

Einzellichtemissionsspektren unterschiedlicher Intensitäten für unterschied-lich farbige LEDs;

Figur 5

ein sich aus der in Figur 4 dargestellten Einzellichtemissionsspektren erge-bendes Gesamtlichtemissionsspektrum;

Figur 6

ein weiteres Beispiel analog zu Figur 4, und

Figur 7

ein Gesamtlichtemissionsspektrum aus Einzellichtemissionsspektren nach Figur 6.

Show it:

FIG. 1

a perspective view from below of a lamp with LED modules;

FIG. 2

an enlarged view of an embodiment of an LED module;

FIG. 3

an enlarged view of another embodiment of an LED module;

FIG. 4

Single light emission spectra of different intensities for differently colored LEDs;

FIG. 5

one out of the in FIG. 4 shown individual light emission spectra resulting total light emission spectrum;

FIG. 6

another example analogous to FIG. 4 , and

FIG. 7

a total light emission spectrum from single light emission spectra FIG. 6 ,

FIG. 1 shows a perspective view obliquely from below of a lamp 2 with an LED module according to the invention 1. In the illustrated embodiment, corresponding LED modules 1 are arranged as a light source 13 on both sides to a light exit opening 11 in a lamp housing 10. The LED modules 1 are both simultaneously controlled and supplied with voltage or current. The illustrated luminaire 2 is shown only by way of example and simplified, wherein it can be used, for example, to illuminate paths, roads or the like. In order to avoid or at least reduce an existing glare effect of the corresponding light means within the luminaire 2, the light exit opening 11 may be associated with a glare limiting device 12 which, for example, reduces the light exit opening 11 in the direction of the surface to be irradiated and possibly additionally emits light emitted by the light source limited to a specific area for lighting only.

There are different embodiments for a corresponding LED module 1 conceivable, wherein in the FIGS. 2 and 3 two embodiments are shown.

According to the embodiment FIG. 2 an arrangement of corresponding LEDs 4 along a row 8. The LEDs 8 are all arranged on an LED support 3, which is formed for example as a printed circuit board. The LED carrier 3 with LEDs 4 after FIG. 2 or after FIG. 3 forms a corresponding LED module 1. It should again be noted that, for example, the arrangement and number of LEDs 4 on the corresponding LED carrier 3 is shown only by way of example and with a small number of LEDs 4. It is also possible, more LED carrier 3 or LED modules 1 in the light 2 after FIG. 1 to use.

The various LEDs 4 on the carrier 3 are different colored LEDs and have, depending on the color, a different individual light emission spectrum, see also FIGS. 4 and 6 , LEDs are essentially monochromatic light sources, ie they emit light only in a narrow-band or limited spectral range. By selective selection of appropriate semiconductor materials and their doping, the properties of the light generated by LEDs can be varied. Today, there are LEDs of red, orange, yellow, green, blue and violet color. Also beyond this visible range of the light spectrum radiation can be produced by LEDs, see, for example, the near infrared range up to a wavelength of 1000 nm or even the ultraviolet range.

In order to produce white light with a light emitting diode, for example, a blue or UV LED is used, with additional photoluminescent material. Similar to fluorescent tubes, this material converts the short-wave and higher-energy light into longer-wave light.

A corresponding number of individual LEDs 4 of different colors are arranged on the LED module 1 or LED carrier 3, see, for example, green LEDs 14, yellow LEDs 15, orange LEDs 16, red LEDs 17, or white LEDs 18.

It should be noted once again that the arrangement and number of LEDs is only an example.

This applies analogously for FIG. 3 in which the corresponding LEDs 4 are arranged both in rows and columns, wherein in the illustrated embodiment five rows and ten columns of LEDs are provided on the corresponding LED carrier 3 and LED module 1, respectively.

Also with this module after FIG. 3 different colored LEDs can be arranged both along a row and a column.

There is also the possibility that a corresponding LED module 1 or LED carrier 3 is composed of sub-modules 7. These may, for example, each have a predetermined number of differently colored LEDs, or be equipped with only monochromatic LEDs. This applies analogously to the embodiment according to FIG. 3 ,

According to the invention, it has proven to be advantageous that the LEDs 4 are controlled differently on the corresponding carrier or by the corresponding module, ie. H. be individually supplied with voltage or power. In this way, the light output of each LED with respect to its individual light emission spectrum is predetermined and well known, so that the various individual light emission spectra can be superimposed on a total light emission spectrum, see the following explanations.

However, it is also conceivable that the sub-modules are controlled separately, and this is particularly advantageous if each sub-module is occupied for example by LEDs of only one color. That is, for example, all of the yellow LEDs could be turned off or on or changed in intensity arranged on a specific sub-module 7. As a result, a corresponding individual light emission spectrum for the light color "yellow" would be missing or at least changed in intensity in the total light emission spectrum. Furthermore, it is possible to provide a plurality of sub-modules, each with the same color LEDs, so that, for example, a sub-module with yellow LEDs, two such sub-modules or more on / off or can be varied in intensity. This applies analogously for differently colored LEDs.

The preceding embodiments are also valid if differently colored LEDs are provided on each submodule, so that, depending on the requirement for the corresponding illumination, fewer or more such submodules are arranged in a luminaire with one another or driven in a luminaire.

In FIG. 4 an embodiment for an LED module 1 with a number of individual light emission spectra 5 is shown. From left to right in FIG. 4 is first a single light emission spectrum for the color green, for the color yellow, for the color orange, and shown in red for the color. The intensities of the corresponding spectra are given as a function of the wavelength in nm, for example, the intensities for the green, red and orange LEDs are equal and substantially three times greater than for the yellow LEDs. If one is sufficiently far away from the corresponding light source 13, or the light 2, the individual light emission spectra overlap to form a total light emission spectrum 6, see FIG. 5 in which no LEDs 4, see Figures 2 or 3, as individual light sources are more recognizable. That is, Figure 5 shows a mixture of four different LED types with different light colors, which may also be provided in different numbers. A corresponding total light emission spectrum 6 can be assembled relatively well before the lamp is constructed by appropriate computer simulation or the like from the individual light emission spectra known per se. D. h., It can be specifically realized a corresponding total light emission spectrum for predetermined lighting purposes in a corresponding light.

In the FIGS. 6 and 7 is shown another embodiment, again from left to right in FIG. 6 corresponding individual light emission spectra 5 for green, yellow, orange, and red LEDs is shown. In this case, the corresponding LEDs are operated with certain percentages of their usual intensity, for example the intensity of the red LED 37, 5%, the green LED 25%, the orange LED 100% and the yellow LED 87.5% respectively of the original or normal operating intensity. In this embodiment, the relative proportion of "green" is reduced compared to FIG. 5 ,

That is, for a species that is sensitive, for example, in the green region, a light source with a total light emission spectrum 6 would be after FIG. 7 advantageous. Conversely, a light source with a total light emission spectrum 6 according to FIG. 5 could be used if value is placed on an increased proportion in the green range.

The remaining parts of the total light emission spectrum according to Figures 5 and 7 are almost unchanged.

By appropriate selection of the number, the color and in particular the variation of the intensities of the various LEDs of a sub-module 7 or the whole LED module 1 further total light emission spectra 6 can be realized as desired and required.

In connection with FIG. 2 was pointed to a white LED 18, which may be provided in addition to the colored LEDs, for example, to increase the color rendering index. Of course, in this context, it is possible to use several such white LEDs.

As explained above, the advantage of the present invention is that even with a relatively small number of LEDs, a controlled mixture of light is possible by using different intensities of the LEDs used in each case. For example, there is no need to change the overall light emission spectrum by turning on or off corresponding LEDs of a given color. That is, in the present invention, a corresponding spectral distribution with a small number of LEDs is possible. This is for example advantageous when small lamps are used, which can provide only a small space for the arrangement of LEDs.

However, there is also the possibility that in addition to the variation of the intensities of the individual LEDs or at least the same color LEDs also and in addition to the intensity variation, a corresponding variation of the number and / or color of the LEDs.

Claims (10)

1. LED module (1) for a luminaire (2) with at least one LED carrier (3) and a plurality of LEDs (4) (light emitting diodes), in particular of a predetermined number and colour, arranged on the LED carrier which are variable relative to one another with regard to the intensities of their individual light emission spectra to emit a total light emission spectrum (6) being composed of individual light emission spectra (5), wherein the total light emission spectrum of the luminaire is substantially free from spectral ranges in which at least one specific species, in particular animal species, has a greater sensitivity as compared to other species, wherein all LEDs can be triggered separately, wherein each LED (4) is configured to emit substantially monochromatic radiation and LEDs having the same monochromatic light radiation are each arranged on a sub-module (7) of the LED module (1), wherein all LEDs can be triggered separately.
2. LED module according to claim 1, characterised in that LEDs having different monochromatic light radiation are each arranged on a further sub-module (7) of the LED module (1).
3. LED module according to claim 1 or 2, characterised in that LEDs can be arranged on the LED carrier (3) along at least one row (8) and/or a column (9).
4. LED module according to any of the preceding claims, characterised in that white LEDs are assigned to the monochromatic LEDs in order to increase a colour rendering index.
5. LED module according to any of the preceding claims, characterised in that the LED modules and/or sub-modules can be arranged in the luminaire to be exchangeable.
6. LED module according to any of the preceding claims, characterised in that the sub-modules (7) can be triggered individually.
7. Luminaire (2) with a luminaire housing (10), at least one LED module (1) according to any of the preceding claims arranged in the luminaire housing (10) as a light source (13), a light emergence opening (11) formed in the luminaire housing (10), and a glare-limiting device (12) assigned in particular to the light emergence opening (11).
8. Luminaire according to claim 7, wherein the luminaire (2) can be applied as a path luminaire, a road luminaire or the like.
9. Method for influencing a light spectrum of a light source (13), which light source is formed of a plurality of individual LEDs arranged on an LED module (1) particularly in rows (8) and/or columns (9), wherein individual emission spectra of the individual LEDs, in particular if the number and the colour of the individual LEDs are predetermined, are superimposed with a variable intensity to a total light emission spectrum as the light spectrum of the light source, wherein the total light emission spectrum of the luminaire is substantially free from spectral ranges in which at least one specific species, in particular animal species, has a greater sensitivity as compared to other species, with simultaneously and separately triggering all individual LEDs by individually triggering the individual LEDs on a sub-module (7) for selecting the number of individual LEDs of a specific colour, wherein each LED (4) is configured to emit substantially monochromatic radiation, and LEDs having the same monochromatic light radiation are each arranged on a sub-module (7) of the LED module (1).
10. Method according to claim 9, characterised by triggering a number of white LEDs in addition to the triggered coloured LEDs.

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