Lighting system with metamerism control

Abstract

Method for operating a lighting device (6), in particular cabin lighting, especially in an aircraft, wherein - a target color point (OS) is specified for the light (8) emitted by the lighting device (6), characterized in that - at least two different values ​​(W1,2) of at least one metamerism parameter (M) are provided for selection, - for each value (W1,2) of the metamerism parameter (M) a corresponding spectral distribution (V1,2) of the light (8) emitted by the lighting device (6) is determined such that - that the color point (O) of the light (8) emitted by the lighting device (6) corresponds to the target color point (OS) for each value (W1,2), and - that for a target surface (FZ) which is irradiated with the light (8) emitted by the lighting device (6), the light (8) reflected from the target surface (FZ) exhibits a metamerism effect (E) for the different spectral distributions (V1,2), - for each value (W1,2) of the metamerism parameter (M) the corresponding spectral distribution (V1,2) is determined in such a way, - that for a reference surface (FR) which is irradiated with the light (8) emitted by the lighting device (6), the light (8) reflected from the irradiated reference surface (FR) has the same color coordinate (O3) for the different spectral distributions (V1,2), and - that the light (8) reflected from the reference surface (FR) exhibits no metamerism effect (E) for all values ​​(W1,2) of the metamerism parameter (M). - one of the values ​​(W1,2) of the metamerism parameter (M) is selected, - the lighting device (6) emits light (8) of the associated spectral distribution (V1,2).

Description

[0001] The invention relates to a lighting device, in particular as cabin lighting in a vehicle, in particular in an aircraft, for example, interior lighting for an aircraft cabin. In the lighting device, a target color location for the light emitted by the lighting device can be specified.

[0002] Particularly in the area of ​​cabin lighting in vehicles, and particularly aircraft, it is known that the color of the cabin lighting can be varied. This is achieved, for example, using RGB controls, selection from a color wheel, gamut, or similar. There is also a requirement to highlight certain sections of the cabin. For example, when entering an aircraft cabin, the overhead compartments and / or their handles should be highlighted. During the flight phase, however, such highlighted lighting of overhead compartments is not desired. To achieve this goal, it would be conceivable to provide separate lights to illuminate specific parts of the cabin and to switch these on and off as needed. Providing additional lights requires effort. Additional lights increase the weight of a cabin, which is particularly undesirable in aircraft cabins.

[0003] From DE 10 2011 103 639 A1 a luminaire with at least three illuminants is known, in which the resulting overall emission spectrum can be changed, wherein the luminous intensity of the illuminants can be changed in such a way that a color location of a light color generated by the illuminants is essentially maintained.

[0004] A lighting arrangement is known from DE 10 2010 039 308 A1. This arrangement comprises a luminaire with multiple light sources, each emitting light in a different color, and a control unit for operating the light sources. The control unit is configured to change the spectral composition of the emitted light while maintaining a substantially unchanged color location or color temperature after a user has specified a desired color location or color temperature for the light emission.

[0005] US 2004 / 0 239 243 A1 discloses a light-emitting arrangement comprising a first light source and a second light source. The first and second light sources are aligned such that, when the first and second light sources emit light, the light emitted by the first and second light sources overlaps and is capable of generating effective white light. The light emitted by the first light source has color coordinates that differ from the light emitted by the second light source. One of the light sources can be a photoluminescent source, such as a fluorescent dye or phosphor.

[0006] The object of the invention is to improve lighting.

[0007] The object is achieved by a method according to patent claim 1, a lighting system according to patent claim 10 and a computer program according to patent claim 11.

[0008] A method according to claim 1 serves for operating a lighting device, wherein the lighting device is, in particular, an interior or cabin light, in particular in an aircraft, in particular in its passenger cabin. A target color locus is specified for the light emitted by the lighting device. According to the invention, at least one metamerism parameter further exists. For each of the metamerism parameters, at least two different values ​​are specified for selection. For each value of the metamerism parameter, an associated spectral distribution of the light emitted by the lighting device is determined. The spectral distribution is determined in such a way that, for each value that one of the metamerism parameters can assume, the color locus of the light emitted by the lighting device corresponds to the target color locus.Furthermore, the spectral distribution is determined such that, for a target surface irradiated with the light emitted by the illumination device, the light reflected from the target surface has the following property: Reflected light according to a first spectral distribution of a first value of the metamerism parameter and reflected light according to a second spectral distribution according to a second value of the metamerism parameter exhibit a metamerism effect with respect to one another. One of the values ​​of the metamerism parameter is then selected in the method. The illumination device then emits light with the spectral distribution corresponding to the selected value of the metamerism parameter.

[0009] In the context of the present invention, all statements regarding “colors,” “color location,” “color perception,” etc., refer to those colors as they are subjectively visually perceived by humans.

[0010] In this context, the "metamerism effect" means that the same target surface, when irradiated by two different types of light, each with a different spectral distribution according to the values ​​of the metamerism parameter, leaves a different optical impression on the human observer, i.e., a different visual perception. "Same colors" or "the color coordinate corresponds to the target color coordinate" means, in this context, that a person subjectively perceives no or only a barely noticeable color difference, i.e., the same or almost the same valences are produced in the human eye. This means that in a color space, the color coordinates of the respective color exhibit only a maximum tolerable deviation from one another.For example, the color coordinates in a CIELUV-1976 color space are less than five, four, or three SDCM (standard deviation of color matching) apart. However, any sharper or fuzzier measure is also conceivable.

[0011] The corresponding spectral distribution for each value of a metamerism parameter is determined empirically, by calculation, or by determination based on experiments, etc. Examples of metamerism parameters include the "warmth impression" of a color. The metamerism parameter can be specified as a qualitative descriptor and / or as a numerical value. Possible values ​​here include "warm" or "cool." Another example of a metamerism parameter is the "naturalness" of the perceived color. Possible values ​​here include "neutral," "artificial," or "natural."

[0012] The invention is based on the following considerations. In luminaires or lighting devices that mix light from at least three primary colors or more, the same color location can be adjusted with different spectral distributions, i.e., spectra. This means that on a white surface, the color location for reflected light is the same, even for different spectra. Colored surfaces, or those that exhibit a so-called metamerism effect, on the other hand, reflect "different light," for example, of a different color or a different human visual perception. Until now, lighting devices or luminaires were always adjusted to only one color location, without the spectrum, i.e., the underlying spectral distribution of the light, being particularly adapted.The color location was selected, for example, using RGB (red, green, blue) controls or a color wheel. This was done, for example, using conventional control devices or control software for the lighting system. The selection was also made within a gamut or similar. In this case, it was difficult or even impossible to select different light spectra for the same color location.

[0013] The invention is based on the peculiarities of the human eye's perception of colors and optical impressions and the spectral distribution of the primary light colors. According to the invention, in addition to selecting the color location, a value for an additional parameter, namely the metamerism parameter, is also selected in order to achieve a targeted adjustment of the spectrum of the generated light. The corresponding selection is made, for example, via a suitable user interface in software. For example, an algorithm operating according to the method according to the invention then adapts the light spectrum, for example the sum spectrum of individual luminaires, based on the metamerism parameter to the desired effect, which is described by the value of the metamerism parameter.

[0014] The adjustment is achieved by controlling the individual light sources of a lighting system (e.g., the R, G, B, and W LEDs of a combination luminaire) with different weightings. The individual luminaires then operate at different individual intensities, resulting in the desired spectrum as a combined spectrum.

[0015] The invention provides the advantage that a desired lighting ambience can be created in an environment that is irradiated with light by the lighting device, for example on interior surfaces in the passenger cabin of an aircraft. For example, it is thus possible to use white light emitted by the lighting device throughout the entire room, with white light of the same color location with an increased proportion of long-wave light waves being used in the area of ​​wooden surfaces as target surfaces. The metamerism effect occurs so that the surface of the wood is visually perceived by the observer as "more lively" due to the metamerism effect. According to the invention, a desired color rendering or a desired metamerism effect can be set in an environment illuminated by the lighting device using a simple tool, namely the selection of a value of a metamerism parameter.

[0016] In a preferred embodiment of the method, the light reflected from the target surface exhibits colors of different color loci as a metamerism effect, with the respective color locus depending on the metamerism parameter. In other words, depending on the value of the metamerism parameter—that is, depending on the type of incident light—the target surface reflects light of different colors, which are perceived by a human observer with distinguishable color valence. The value of the metamerism parameter is then, for example, the size of the color difference in a color space.

[0017] In a preferred embodiment of the method, the spectral distributions of the light emitted by the illumination device are determined as follows: The spectral intensities are changed in the overall spectrum within a specific wavelength or frequency range. In the spectrum, the range of all wavelengths or frequencies belonging to the light visible to humans forms an overall range. The range in which the spectrum is changed is a true subrange—i.e., smaller than the overall range—of the overall range. The change occurs depending on the value of the metamerism parameter. In other words, for example, in a blue or red range of the visible light spectrum, the intensity of the spectral distribution is increased or decreased depending on the value of the metamerism parameter in order to achieve the desired metamerism effect.If necessary, other parts of the spectrum may also need to be adjusted in terms of intensity to achieve the desired color coordinate of the light according to the target color coordinate. In this case, the metamerism parameter is, for example, an intensity, and its values ​​are intensity values ​​or intensity distributions, i.e., spectral distributions.

[0018] In a variant of the aforementioned embodiment, a wood or wood-effect surface is selected as the target surface, and the intensity in a red sub-range of the spectral distribution is changed depending on the metamerism parameter in the spectral distribution. The metamerism parameter is then the red intensity, whose values ​​indicate an intensity value or an intensity distribution in the corresponding frequency or wavelength range.

[0019] Alternatively, but as above, a stone or stone-like surface is selected as the target surface. Depending on the metamerism parameter, the intensity is changed to a blue sub-range of the spectral distribution. The metamerism parameter is then the blue intensity, whose values ​​indicate an intensity value or an intensity distribution in the corresponding frequency or wavelength range.

[0020] According to the method, for each value of the metamerism parameter, the corresponding spectral distribution of the light emitted by the illumination device is determined such that, for a reference surface irradiated with the light emitted by the illumination device, the light reflected from the irradiated reference surface has the same color location for the various spectral distributions. This ensures that when the value of the metamerism parameter changes in an environment illuminated by the illumination device, the visual perception of objects with a target surface changes, while the visual color perception of objects with a reference surface remains the same.In this way, it can be achieved that the target objects are visually accentuated or their optical appearance is changed for a viewer, but the reference surfaces are visually perceived in a consistent manner and thus leave a constant visual impression.

[0021] The light reflected from the reference surface not only exhibits the same color location for all values ​​of the metamerism parameter, but also exhibits no metamerism effect at all. Objects then not only appear the same color but are also visually perceived as consistent in other respects.

[0022] In a preferred embodiment of the method, a white color location is specified as the target color location for the light emitted by the lighting device. The desired effect can thus be achieved even with "neutral" light, i.e., light emitted by the lighting device in a white color. "White" is understood here to mean any light color that is not explicitly perceived as colorful, i.e., that may exhibit a subjectively barely perceptible color shimmer. The corresponding color location lies, for example, within a radius of 2, 3, 5, 10, or 20 SDCM around the white point of a color space.

[0023] In a further preferred embodiment of the method, a u'v' value of a CIE 1976 LUV color space is used as the color location. This color space is frequently used, thus making the results of the method comparable and reproducible.

[0024] In a preferred embodiment, a light source arrangement comprising at least three individual light sources is used as the illumination device, with the individual light sources each having different light spectra in pairs. The color location is then selected within the gamut spanned by the individual light sources in a color space. In particular, the light source arrangement is a light-emitting diode arrangement, and the individual light sources are individual light-emitting diodes. Different spectral distributions of the emitted light are then generated by differently weighted control of the individual light sources.

[0025] The spectral distribution for a given metamerism parameter value is determined by combining the spectra of the individual light sources with different weightings to create composite spectra. This takes into account that light of a color according to a specific target color location can be generated by different light mixtures from the individual light sources. This possibility for different mixing provides the necessary degree of freedom to change the light spectra for different values ​​of the metamerism parameter while maintaining the same color location.

[0026] In a preferred embodiment, an RGBW (red-green-blue-white) LED array is used as the lighting device. Such LED arrays are commercially available, so a corresponding lighting device can be easily implemented.

[0027] The object is further achieved by a lighting system according to claim 10 with the above-described lighting device. The lighting system also has a computing device. This has a first input for a desired color location for light emitted by the lighting device. Furthermore, the computing device has an output for controlling the lighting device. According to the invention, the computing device has a second input for inputting a value of the metamerism parameter and is designed to carry out the method according to the invention.

[0028] The object is also achieved by a computer program according to claim 11 with program code means for carrying out all steps of the method according to the invention when the program is executed on a computer and / or on the lighting system according to the invention.

[0029] The lighting system and computer program have already been explained in connection with the above-mentioned method, together with their advantageous designs and advantages.

[0030] Since the lighting system and the computer program generate light as explained above or contribute to its generation, the advantageous embodiments and advantages mentioned above in connection with the method according to the invention also apply to the lighting system and the computer program. With regard to the reference and target surfaces, these are not part of the lighting system or computer program, respectively, but are then coordinated with the corresponding surfaces in order to interact with them in accordance with the invention.

[0031] Further features, effects, and advantages of the invention will become apparent from the following description of a preferred embodiment of the invention and the accompanying figures. These show: Fig. 1 a lighting system according to the invention, Fig. 2 spectral distributions of light of the same color, Fig. 3 light colors of generated and reflected light in a color space, Fig. 4 a lighting device with individual light sources, Fig. 5 a user interface of a computer program, Fig. 6 a block diagram of the method according to the invention.

[0032] Fig. Figure 1 schematically shows a passenger cabin 2 of an aircraft in the form of an airplane 4. A lighting device 6 is arranged there to illuminate the interior of the passenger cabin 2. The lighting device 6 emits light 8. A person 10, here, for example, a passenger of the airplane 4, perceives the light 8 emitted or generated directly by the lighting device 6 as having a specific color F.

[0033] The aircraft 4 further includes a computing device 12 with an output 14 for controlling the lighting device 6 via a control device 13. Furthermore, the computing device 12 has a first input 16a and a second input 16b. A target color location OS is fed into the computing device 12 via the first input 16a. The target color location OS specifies that the light 8 emitted by the lighting device 6 should, if possible, have the color location O corresponding to the target color location OS in order to thus determine the desired color F of the light 8. A metamerism parameter M, which can assume at least two values ​​W1,2, is fed into the computing device 12 via the input 16b. Fig. 1 this is symbolically represented by a double arrow in the form of a slider. Symbolically, Fig. 1 only two different values ​​W1 and W2 are shown. The computing device 12 now determines a first spectral distribution V1 for the emitted light 8 for the first value W1, which has a color location O equal to the target color location OS. In Fig. 1 is symbolically the spectral distribution V plotted as intensity I over the wavelength λ. For the value W2, the computing device 12 determines a second spectral distribution V2 for the light 8, which produces at least approximately the same color valence of the color F in the human 10. This means that the light 8 according to the spectral distribution V2 also has the target color location OS as the color location O.

[0034] In the simplest case, the spectral distributions V1, V2 are determined by taking them from a memory—e.g., a database—or a look-up table based on the value W1, W2. The spectral distributions V1, V2 for generating light 8 according to a desired metamerism effect E based on the value W1, W2 were determined, for example, through experiments before being stored or stored in the look-up table.

[0035] Depending on the currently selected value W1 or W2 of the metamerism parameter M, the illumination device 6 is controlled to generate light of the corresponding spectrum V1 or V2. To operate the illumination device 6, the computing device 12 then generates a control signal at output 14, which controls the illumination device 6 to generate light 8 of the spectral distribution V1 or V2 according to the currently entered value W1 or W2. The actual control of the illumination device 6 is performed by the control unit 13, which generates appropriate control signals. If the lighting device 6 is, for example, an RGBW LED (red-green-blue-white), corresponding R, G, B, and W signals are generated so that the LEDs generate the spectral distribution V1 or V2 as a sum spectrum. In the example, this is symbolically represented by control values ​​for individual light sources 26 a - d in the form of an "RGBW" value quadruple.

[0036] The computing device 12 can be located inside or outside the aircraft 4. It is crucial that corresponding control signals for the lighting device 6 are generated or prepared for later use. For example, the control signals for the lighting device 6 for generating different types of light of the spectra V1 and V2 are generated in advance and, if necessary, outside the aircraft 4. The signals are then stored in a memory 15 of the control device 13 and retrieved as needed and transmitted to the lighting device 6.

[0037] The two spectral distributions V1, V2 are different and selected such that light 8, which the person 10 perceives not as emanating directly from the lighting device 6 but as light reflected from a target surface FZ, evokes a different visual perception in the person 10 depending on the selected spectral distribution V1 or V2. A metamerism effect E thus arises between the two light variants reflected from the target surface FZ, which originate from incoming light 8 of the spectral distributions V1 and V2. In the example, the target surface FZ, as a wooden surface, appears "natural" or "deep" in one case, and "neutral" or "flat" in the other case.In an alternative embodiment, the metamerism effect E consists in that the light 8 of the spectral distribution V1 generated by the illumination device 6 has the color location O1 after reflection at the target surface FZ - now a plastic surface - and corresponding light of the spectral distribution V2 has the color location O2 after reflection.

[0038] In an alternative embodiment, the spectral distributions V1, V2 are further selected such that light which is reflected from a reference surface FR - different from the target surface FZ - does not show any metamerism effect for both spectral distributions V1, V2, which in Fig. 1 is symbolized by the letter "K". The absence of a metamerism effect means, for example, that the reflected light corresponding to incident light of the different spectral distributions V1, V2 has the same color location O3 and does not otherwise cause any different visual perception in humans 10.

[0039] Fig. 2 shows the two spectral distributions V1 and V2 from Fig. 1, which are determined according to the values ​​W1,2 of the metamerism parameter M and the target color location OS, in a common diagram. In Fig. 2 shows how, in order to achieve the metamerism effect E, the intensity I of the spectral distribution V is changed as a function of the value W1, W2 of the metamerism parameter M in a sub-range 18 of the entire wavelength range. The sub-range 18 is a true sub-range of the total range 20. The total range 20 describes the entire range of visible light 8 perceivable by humans 10. In the remaining total range 20, the spectral distribution V1,2 is adjusted accordingly in order to achieve the same color location OS for both spectral distributions in the generated light 8.

[0040] In the example, sub-area 18 is the range of short-wave light, i.e., the blue range. The target surface FZ is then a stone or stone-like surface. A change in the blue light component in the spectral distribution V results in a metamerism effect E between the spectral distributions V1 and V2, which causes the surface to be subjectively visually perceived by a person 10 as particularly "natural" or "deep," and in the other case, rather as "neutral" or "flat."

[0041] Fig. Figure 3 shows a color space 22, here the CIE 1976 Lu'v' color space. An arbitrary color location O is determined by the coordinates u'v', as shown for the nominal color location OS. Fig. 3 shows that it is permissible for the actually generated color location O of the light 8 emitted by the lighting device 6 not to lie exactly at the color location OS, but may also lie in its immediate vicinity - in a range 24. Humans 10 perceive all color locations O in range 24 as having the same or at least approximately the same color value. The size of range 10 is set such that the color deviations are perceived as tolerable, e.g. 2, 3, 4, 5, 10 or 20 SDCM. Range 24 therefore defines an error measure for a permissible deviation of the actual color location O from the target color location OS. The size of range 24 describes how much color deviation is acceptable when generating light 8 of different spectral distributions V1, V2. Fig. 3 also shows the color coordinates O1 and O2 of the light reflected from the target surface FZ as well as the color coordinate O3 of the light reflected from the reference surface FR Fig. 1. The distance between the color coordinates O1, O2 describes the metamerism effect E. The parameter M or value W for this is the distance between the two color coordinates in the u'v' coordinate system.

[0042] Fig. 3 also shows the white color location OW and a tolerance range 24 surrounding it. If light 8 is selected according to a target color location OS within this white range 24, the direct, i.e. non-reflected light, is perceived by the observer as white light.

[0043] Fig. Figure 4 shows a lighting device 6 in the form of a light source arrangement 26, which is composed of three individual light sources 26a-c, here individual light-emitting diodes of the colors R, G, B (red, green, blue). Each of the individual light sources 26a-c has its own spectral distribution V of the light 8 emitted by it. Optionally, a further individual light source 26d is present, in the example a single light-emitting diode of the color W (white). Fig. Figure 4 schematically illustrates how the computing device 12 determines the spectral distributions V1, V2 such that they are generated as a sum spectrum of the differently weighted individual spectra V of the individual light sources 26a-d, i.e., by changing the corresponding individual intensities (solid for W1, dashed for W2). The colors F, which can be generated by any desired mixture of the individual light sources 26a-c, all lie within the gamut 23 of the light source arrangement 26.

[0044] Here too, in the simplest case, the spectral distributions V1, V2 are determined in such a way that the spectral distributions of the individual light sources 26a-d for each value W1, W2 are stored in a memory or a look-up table and are read out when required.

[0045] Fig. 5 shows an example of a section of a user interface of a software for implementing the method according to the invention in the computing device 12. Fig. 5a, basic or pre-settings for the lighting device 6 can first be made. For example, the target color location OS is defined in a known manner. Various pre-settings are then available for the metamerism parameters M, e.g., in the form of the parameter sets "CRI" (color rendering index), "wood," or "marble." Specific values ​​W of the existing metamerism parameters M are located behind the respective parameter sets. The pre-setting "CRI" means "CRI-optimized" and causes the metamerism indices or the generated light spectra to be set to a standard value. The pre-setting "Wood" causes wooden surfaces in an otherwise neutral environment to be particularly emphasized by the lighting, while the pre-setting "Marble" means that marble surfaces are subjectively optically emphasized.

[0046] Fig. Figure 5b shows a two-dimensional controller of the software for individually and simultaneously controlling two metamerism parameters. The image symbolizes a three-dimensional sphere that can be rotated in all directions—here using a computer mouse. Instead of the aforementioned presets, the values ​​W of two metamerism parameters M can be individually adjusted. In the horizontal direction, a first metamerism parameter M is selected, which can vary between the values ​​"warm" and "cool." In the vertical direction, a second metamerism parameter M is varied between the values ​​"neutral" and "natural."

[0047] In a section of the user interface (not shown), a pattern with multiple colors is displayed. It also shows how the color coordinate O of the emitted light 8 can be slightly altered compared to the target color coordinate OS, for example, if a more metameric effect E is desired.

[0048] Fig.6 shows a block diagram for the method according to the invention. First, a target color location OS is specified by specifying coordinates u'v' of the color space 22. Furthermore, a brightness L is specified. This uniquely characterizes the generated light 8 with regard to color F and brightness for human perception. A first algorithm 28 is used to calculate the RGBW color components in the individual light sources 26a-d, i.e., the weighting or intensities or brightness values ​​with which they are to be controlled in order to generate such light with a standard light spectrum. The standard corresponds, for example, to the aforementioned "CRI" setting. In other words, the desired color F is converted - in a known manner - into the color components of the respective individual light sources 26a-d. This was determined, for example, once through testing or is specified by the manufacturer as a standard color mixture. According to the invention, the metamerism parameter M is now also specified.

[0049] A second algorithm 30 according to the invention then adapts the RGBW color components of the individual light sources 26a-d determined by the first known algorithm 28 in order to additionally achieve a specific light spectrum for generating the metamerism effect E according to the selected value of the metamerism parameter M. In other words, the color components of the individual light sources 26a-d are—as a rule—changed throughout the light to obtain the desired spectrum while maintaining the color location. The reference spectra of the individual light sources 26a-d are incorporated into this algorithm as system parameters 32. As a result, the method delivers adapted RGBW color components for the individual light sources 26a-d corresponding to the brightness L at the color location u'v', which are suitable for generating the desired metamerism effect E on the target surface, depending on the value W of the metamerism parameter M. List of reference symbols 2 passenger cabins 4 aircraft 6 Lighting equipment 8 light 10 people 12 computing device 13 Control device 14 Exit 15 storage 16a first entrance 16b second entrance 18 sub-area 20 total area 22 color space 23 Gamut 24 area 26 Light source arrangement 26a-d Single light source 28 first algorithm 30 second algorithm 32 system parameters E Metamerism effect F Color FR Reference Surface FZ target surface I Intensity K no metamerism effect L Brightness λ wavelength M metamerism parameter O color location 01,2,3 color location OS target color location OW white color location V spectral distribution V1,2 spectral distribution W value W1.2 value RGBW Red Green Blue White

Claims

[1] Method for operating a lighting device (6), in particular a cabin lighting, in particular in an aircraft, in which - a target color location (OS) is specified for the light (8) emitted by the lighting device (6), characterized by , that - at least two different values (W1,2) of at least one metamerism parameter (M) are specified for selection, - for each value (W1,2) of the metamerism parameter (M), an associated spectral distribution (V1,2) of the light (8) emitted by the illumination device (6) is determined in such a way, - that the color location (O) of the light (8) emitted by the lighting device (6) corresponds to the desired color location (OS) for each value (W1,2), and - that for a target surface (FZ) which is irradiated with the light (8) emitted by the illumination device (6), the light (8) reflected from the target surface (FZ) has a metamerism effect (E) for the different spectral distributions (V1,2), - for each value (W1,2) of the metamerism parameter (M) the corresponding spectral distribution (V1,2) is determined in such a way, - that for a reference surface (FR) which is irradiated with the light (8) emitted by the illumination device (6), the light (8) reflected by the irradiated reference surface (FR) has the same color location (O3) for the different spectral distributions (V1,2), and - that the light (8) reflected from the reference surface (FR) does not exhibit a metamerism effect (E) for all values (W1,2) of the metamerism parameter (M) - one of the values (W1,2) of the metamerism parameter (M) is selected, - the lighting device (6) emits light (8) of the corresponding spectral distribution (V1,2). [2] Method according to claim 1, characterized by that the reflected light (8) has, as a metamerism effect (E), colors (F) of different color locations (O1, 2), wherein the respective color location (O1, 2) depends on the metamerism parameter (M). [3] Method according to one of the preceding claims, characterized by that the spectral distributions (V1,2) are determined in such a way that, depending on the value (W1,2) of the metamerism parameter (M), the intensity (I) in the spectrum is changed within a real sub-range (18) of the total range (20) belonging to the visible light. [4] Method according to claim 3, characterized by that a wood or wood-imitation surface is selected as the target surface (FZ), and the intensity (I) is changed in a red sub-range of the spectral distribution (V1,2). [5] Method according to claim 3 or 4, characterized by that a stone or stone replica surface is selected as the target surface (FZ), and the intensity (I) is changed in a blue sub-range of the spectral distribution (V1,2). [6] Method according to one of the preceding claims, characterized by that a white color location (OW) is specified as the target color location (OS) for the light (8) emitted by the lighting device (6). [7] Method according to one of the preceding claims, characterized by that a u'v' value of a CIE 1976 Lu'v' color space (22) is used as the color location (O). [8] Method according to one of the preceding claims, characterized bythat a light source arrangement (26) with at least three individual light sources (26a-d) with different light spectra (V) is used as the illumination device (6), and the color location (O) is selected within the gamut (23) spanned by the individual light sources (26a-d) in a color space (22), and different spectral distributions (V1, 2) of the emitted light (8) are generated by differently weighted control of the individual light sources (26a-d). [9] Method according to claim 8, characterized by that an RGBW light-emitting diode arrangement is used as the lighting device (6). [10] Lighting system, with a lighting device (6), in particular a cabin lighting, in particular in an aircraft, - with a computing device (12) with a first input (16a) for a desired color location (OS) for light (8) emitted by the lighting device (6), and an output (14) for controlling the lighting device (6), characterized by that the computing device (12) - a second input (16b) for inputting a value (W1,2) of a metamerism parameter (M), and - is designed to carry out a method according to one of claims 1 to 9. [11] A computer program comprising program code means for performing all steps of the method according to any one of claims 1 to 9 when the program is executed on a computer and / or on the lighting system of claim 10.

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