INTERIOR AIRCRAFT LIGHTING DEVICE, AIRCRAFT COMPRISING AN INTERIOR AIRCRAFT LIGHTING DEVICE AND METHOD OF STARTING AN INTERIOR AIRCRAFT LIGHTING DEVICE

Abstract

An interior aircraft lighting device includes at least two discharge light modules, including at least one first discharge light module and at least one second discharge light module, wherein each discharge light module contains at least one excitable gas, which emits electromagnetic radiation pursuant to electric excitation The device also includes multiple electrodes, wherein at least one pair of electrodes is assigned to each discharge light module for applying an electric field to the at least one excitable gas within the respective discharge light module. The two electrodes of each pair of electrodes are spaced apart from each other along a longitudinal direction (A) of the respective discharge light module. The pairs of electrodes include at least one first pair of electrodes assigned to the at least one first discharge light module, and at least one second pair of electrodes assigned to the at least one second discharge light module.

Claims

1. An interior aircraft lighting device, comprising: at least two discharge light modules, including at least one first discharge light module and at least one second discharge light module, wherein each discharge light module contains at least one excitable gas, which emits electromagnetic radiation pursuant to electric excitation; and multiple electrodes, wherein at least one pair of electrodes is assigned to each discharge light module for applying an electric field to the at least one excitable gas within the respective discharge light module; wherein the two electrodes of each pair of electrodes are spaced apart from each other along a longitudinal direction (A) of the respective discharge light module; wherein the pairs of electrodes include at least one first pair of electrodes, which is assigned to the at least one first discharge light module, and at least one second pair of electrodes, which is assigned to the at least one second discharge light module; and wherein a distance (a.sub.1, a.sub.11, a.sub.12) between the two electrodes of the at least one first pair of electrodes is smaller than a distance (a.sub.2) between the two electrodes (6a, 6b) of the at least one second pair of electrodes.

2. The interior aircraft lighting device according to claim 1, comprising: at least two first pairs of electrodes and at least two first discharge light modules, wherein at least one of the at least two first pairs of electrodes is assigned to each of the at least two first discharge light modules, respectively; and at least two second pairs of electrodes and least two second discharge light modules, wherein at least one of the at least two second pairs of electrodes is assigned to each of the at least two second discharge light modules, respectively; wherein the distance (a.sub.1, a.sub.11, a.sub.12) between the two electrodes of each of the at least two first pairs of electrodes is smaller than the distance (a.sub.2) between the two electrodes of each of the at least two second pairs of electrodes.

3. The interior aircraft lighting device according to claim 1, wherein the distance (a.sub.1, a.sub.11, a.sub.12) between the two electrodes of the at least one first pair of electrodes is between 2 mm and 7 mm.

4. The interior aircraft lighting device according to claim 1, wherein the at least two discharge light modules are arranged next to each other in a side-by-side arrangement such that electromagnetic radiation, which is emitted by one of the at least two discharge light modules, excites the at least one excitable gas in at least one other discharge light module; wherein the at least two discharge light modules are in particular arranged in a parallel configuration, so that the longitudinal directions of the discharge light modules are oriented basically parallel to each other.

5. The interior aircraft lighting device according to claim 1, wherein the at least two discharge light modules are supported by a common support, in particular by a common support plate, or wherein the interior aircraft lighting device comprises two, three, four, five, six, seven, eight, nine or ten discharge light modules.

6. Interior aircraft lighting device according to claim 1, wherein at least two pairs of electrodes are assigned to a particular first discharge light module, or wherein at least two pairs of electrodes are assigned to a particular second discharge light module.

7. The interior aircraft lighting device according to claim 1, wherein the electromagnetic radiation, emitted by the at least one excitable gas, includes electromagnetic radiation in the range of ultraviolet light in the range from 210 nm to 230 nm.

8. The interior aircraft lighting device according to claim 1, including an electric power supply for supplying electric power to each pair of electrodes, wherein the electric power is in particular supplied with a voltage (U) between 1000 V and 5000 V.

9. A passenger aircraft comprising: at least one interior aircraft lighting device according to claim 1.

10. The passenger aircraft according to claim 9, further comprising: a lavatory and/or a galley, wherein at least one interior aircraft lighting device is installed within the lavatory and/or within the galley of the aircraft.

11. The passenger aircraft according to claim 9, further comprising: at least one passenger seat and at least one passenger service unit arranged above the at least one passenger seat; wherein at least one interior aircraft lighting device is arranged for irradiating at least a portion of the at least one passenger seat and/or the at least one passenger service unit with electromagnetic radiation, which is emitted by the at least two discharge light modules of the at least one interior aircraft lighting device.

12. A method of starting an interior aircraft lighting device according claim 1 comprising: applying an electric voltage (U) to each pair of electrodes of the at least two discharge light modules, wherein the electric voltage (U) is an electric voltage (U) between 1000 V and 5000 V.

13. A method of disinfecting at least one component or surface within an aircraft, in particular within a passenger aircraft, wherein the method includes: starting an interior aircraft lighting device according claim 1 for emitting electromagnetic radiation by applying an electric voltage (U) to each pair of electrodes of the at least two discharge light modules, wherein the electric voltage (U) is an electric voltage (U) between 1000 V and 5000 V; and irradiating the at least one component or surface with electromagnetic radiation emitted by the at least two discharge light modules of the interior aircraft lighting device.

14. The method according to claim 13, wherein the at least one component or surface includes a portion of a passenger seat and/or a passenger service unit, and/or or wherein the at least one component or surface is located within at least one of a lavatory and a galley of the aircraft.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0054] Further exemplary embodiments of the invention are described below with respect to the accompanying drawings, wherein:

[0055] FIG. 1 depicts an aircraft, in particular an air plane, in accordance with an exemplary embodiment of the invention in a schematic side view.

[0056] FIG. 2 depicts a schematic view of an overhead passenger service unit (PSU).

[0057] FIG. 3 depicts a schematic cut-open view of an aircraft in accordance with an exemplary embodiment of the invention, showing a passenger cabin of the aircraft.

[0058] FIG. 4 depicts a schematic view of an interior aircraft lighting device according to an exemplary embodiment of the invention.

[0059] FIG. 5 depicts a schematic view of an interior aircraft lighting device according to a further exemplary embodiment of the invention.

DETAILED DESCRIPTION

[0060] FIG. 1 depicts an aircraft 100, in particular an air plane, in accordance with an exemplary embodiment of the invention in a schematic side view. In the exemplary embodiment shown in FIG. 1, the aircraft 100 is a large passenger air plane, comprising a cockpit 103 and a passenger cabin 104 housing a plurality of passenger seats 106. The aircraft 100 may be a commercial passenger air plane, a private air plane, or a military aircraft. It is also possible that the interior aircraft lighting device and the method according to exemplary embodiments of the invention are implemented in a rotorcraft, such as a helicopter.

[0061] Passenger service units (PSU) 102 are arranged above the passenger seats 106.

[0062] In an exemplary configuration, in which the aircraft 100 comprises six passenger seats 106 per row (cf. FIG. 3, which will be discusses in more detail further below), each row of passenger seats 106 may have two passenger service units 102 associated therewith, one passenger service unit 102 assigned to the passenger seats 106 on the left side of a center aisle 114 and one passenger service unit 102 assigned to the passenger seats 106 on the right side of the center aisle 114.

[0063] FIG. 2 depicts a schematic view of an overhead passenger service unit (PSU) 102, which is arranged above the passengers of a single passenger row, as it is seen from the side of a passenger sitting on a passenger seat 106 below the overhead passenger service unit 102.

[0064] On the side, which is shown to the left in FIG. 2, the overhead passenger service unit 102 comprises a row of three adjustable reading lights 26a-26c, which are arranged next to each other.

[0065] Six electrical switches 27a-27c, 28a-28c are provided to the right side of the reading lights 26a-26c, a respective pair of two switches 27a-27c, 28a-28c next to each of the reading lights 26a-26c. One of the switches 27a-27c of each pair is configured for switching the adjacent reading light 26a-26c, and the second switch 28a-28c of each pair is configured for triggering a signal for calling cabin service personnel.

[0066] A row of three adjacent gaspers 29a-29c is provided next to the switches 27a-27c, 28a-28c.

[0067] Adjacent to the gaspers 29a-29c is a removable cover 40, which covers a cavity housing at least three oxygen masks (not shown). In the event of a pressure loss within the cabin, the removable cover 40 will open, the oxygen masks will drop out of the cavity, and each of the passengers, sitting below the overhead passenger service unit 102, may grasp one of the oxygen masks. The oxygen masks will be supplied with oxygen allowing the passengers to continue to breathe normally.

[0068] On the side opposite to the gaspers 29a-29c, a grid 42 is formed within the overhead passenger service unit 102. A loudspeaker (not shown), which may be used for delivering acoustic announcements to the passengers, is arranged behind said grid 42.

[0069] Next to the grid 42, there is a display panel 44, which may be configured for selectively showing a plurality of visual signs (not shown), such as “non smoking” or “fasten you seat belt”. The display panel 44 may be illuminated from behind, in order to deliver visual information to the passengers sitting below the overhead passenger service unit 102.

[0070] FIG. 3 depicts a schematic cut-open view of an aircraft 100 in accordance with an exemplary embodiment of the invention, depicting a passenger cabin 104 of the aircraft 100, also referred to as aircraft passenger cabin 104 herein.

[0071] The aircraft passenger cabin 104 is equipped with a plurality of passenger seats 106. The passenger seats 106 are arranged next to each other forming a plurality of passenger seat rows. Each passenger seat row comprises two groups of passenger seats 106, respectively including three passenger seats 106. The two groups of passenger seats 106 are separated from each other by a center aisle 114, extending along a longitudinal axis A of the aircraft 1.

[0072] The aircraft passenger cabin 104 is further equipped with four lavatories 108a-108d. In the exemplary configuration depicted in FIG. 3, lavatories 108a-108d are provided at four locations within the aircraft passenger cabin 104. A first lavatory 108a is located at the front portside end of the aircraft passenger cabin 104, a second lavatory 108b is located at the front starboard end of the aircraft passenger cabin 104, a third lavatory 108c is located at the rear portside end of the aircraft passenger cabin 104, and a fourth lavatory 108d is located at the rear starboard end of the aircraft passenger cabin 104. Additionally or alternatively, lavatories 108a-108d may be provided at other locations of the aircraft passenger cabin 104 as well.

[0073] The aircraft passenger cabin 104 is further equipped with a galley 110, in order to allow for preparing meals and drinks for the passengers.

[0074] At least one of the lavatories 108a-108d and the galley 110 is provided with an interior aircraft lighting device 2 according to an exemplary embodiment of the invention.

[0075] In the exemplary embodiment depicted in FIG. 3, each lavatory 108a-108d and the galley 110 are provided with an interior aircraft lighting device 2 for generating UV radiation, respectively. However, exemplary embodiments of the invention also include aircraft 100 in which only one or any subset of the lavatories 108a-108d and the galley 110 are provided with an interior aircraft lighting device 2 generating UV radiation.

[0076] Although not explicitly depicted in FIG. 3, interior aircraft lighting devices 2 for generating UV radiation according to exemplary embodiments of the invention may also be provided next to the passenger service units 102 (cf. FIGS. 1 and 2) for disinfecting said passenger service units 102 by irradiating the passenger service units 102 with UV light.

[0077] Interior aircraft lighting devices 2 according to exemplary embodiments of the invention may also be provided within the passenger cabin 104 for irradiating and disinfecting the passenger seats 106 located under the passenger service units 102. The interior aircraft lighting devices 2 may, for example, be integrated into the passenger service units 102 or arranged next to the passenger service units 102.

[0078] Interior aircraft lighting devices 2 according to exemplary embodiments of the invention may also be provided within the cockpit 103 of the aircraft 100 for disinfecting surfaces touched by the pilots.

[0079] As UV light may be harmful to humans, in particular to the human eye, the interior aircraft lighting devices 2 according to exemplary embodiments of the invention, provided within the passenger cabin 104 and/or within the cockpit 103 of the aircraft 100, may be activated only after the passengers and crew have disembarked after the flight, so that no humans are present within the aircraft 100.

[0080] Interior aircraft lighting devices 2 according to exemplary embodiments of the invention, located in the lavatories 108a-108d, however, may also be activated during flight, when the lavatories 108a-108d are not occupied and the doors of the lavatories 108a-108d are closed, so that no or only very small amounts of UV light can exit the lavatories 108a-108d. Interior aircraft lighting devices 2 located within the lavatories 108a-108d may, for example, be activated in regular time intervals or after a predefined number of passengers have used the respective lavatory 108a-108d, in order to ensure hygienic conditions within the lavatories during the flight.

[0081] FIG. 4 depicts a schematic view of an interior aircraft lighting device 2 according to an exemplary embodiment of the invention.

[0082] The interior aircraft lighting device 2 comprises at least two discharge light modules 3, 4, in particular four discharge light modules 3, 4, which are arranged in a side-by-side arrangement next to each other. The number of discharge light modules 3, 4 depicted in FIG. 4 is only exemplary. The skilled person understands that an interior aircraft lighting device 2 according to an exemplary embodiment of the invention may comprise only two discharge light modules 3, 4 or any number of discharge light modules 3, 4, which is larger than two.

[0083] In the embodiment depicted in FIG. 4, each of the four discharge light modules 3, 4 has a tubular shape. Each of the four discharge light modules 3, 4 has a length L in a longitudinal direction A of between 20 mm and 100 mm, in particular a length L of between 40 mm and 80 mm, more particularly a length L of between 50 mm and 70 mm. Each of the four discharge light modules 3, 4 has a diameter D of between 2 mm and 8 mm, in particular a diameter D of between 3 mm and 7 mm, more particularly a diameter D of between 4 mm and 6 mm.

[0084] The distances d between the discharge light modules 3, 4 in a lateral direction B, which is oriented orthogonally to the longitudinal direction A, are between 4 mm and 10 mm, in particular between 5 mm and 9 mm, more particularly between 6 mm and 8 mm.

[0085] The discharge light modules 3, 4 are made of glass or a similar material which is light transmissive and gas tight. Each discharge light module 3, 4 contains at least one excitable gas, in particular a mixture of at least two gases, which emits electromagnetic radiation 14 when an electric field having a sufficient strength is applied to the respective discharge light module 3, 4, so that the electric field passes through the at least one excitable gas.

[0086] In order to allow for applying such an electric field to the at least one excitable gas within the discharge light modules 3, 4, the interior aircraft lighting device 2 comprises a plurality of electrodes 5a, 5b, 6a, 6b. A pair of electrodes 5a, 5b, 6a, 6b is assigned to and arranged next to each discharge light module 3, 4, respectively. The electrodes 5a, 5b, 6a, 6b are located outside the respective discharge light modules 3, 4.

[0087] The discharge light modules 3, 4 and the electrodes 5a, 5b, 6a, 6b may be arranged on a common support 7, in particular a common support plate 7, such as a printed circuit board 7.

[0088] In alternative configurations, the discharge light modules 3, 4 and the electrodes 5a, 5b, 6a, 6b may be supported by different supports 7, in particular by multiple support plates or circuit boards 7. Such a configuration may allow for a more flexible arrangement of the discharge light modules 3, 4.

[0089] For supplying electric power to the electrodes 5a, 5b, 6a, 6b, the electrodes 5a, 5b, 6a, 6b are electrically coupled to an electric power supply 10 via electrical lines 8. Electric conducting paths 9a, 9b may be formed on and/or within the support 7 for electrically coupling the electrodes 5a, 5b, 6a, 6b to the electric power supply 10.

[0090] Each pair of electrodes 5a, 5b, 6a, 6b comprises a first electrode 5a, 6a and a second electrode 5b, 6b, respectively. The first electrodes 5a, 6a of all pairs of electrodes 5a, 5b, 6a, 6b are coupled to a first pole 11a of the electric power supply 10, and the second electrodes 5b, 6b of each pair of electrodes 5a, 5b, 6a, 6b are coupled to a second pole 11 b of the electric power supply 10. In other words, the pairs of electrodes 5a, 5b, 6a, 6b are coupled in parallel to the electric power supply 10. In consequence, the electric power supply 10 applies the same voltage U to all pairs of electrodes 5a, 5b, 6a, 6b.

[0091] The electric power supply 10 is a high voltage power supply 10, which is capable of and configured for applying an electrical voltage of between 1000 V and 5000 V to the electrodes. The electric power supply 10 may be a variable electric power supply 10, which allows for varying the electric voltage U applied to the electrodes 5a, 5b, 6a, 6b.

[0092] In the embodiment depicted in FIG. 4, each electrode 5a, 5b, 6a, 6b has a longitudinal extension b, i.e. an extension in the longitudinal direction A, of between 2 mm and 5 mm, in particular a longitudinal extension b of between 3 mm and 4 mm.

[0093] The discharge light modules 3, 4 include a first discharge light module 3, and a plurality, in particular three, second discharge light modules 4. A first pair of electrodes 5a, 5b is assigned to the first discharge light modules 3. A second pair of electrodes 6a, 6b is assigned to each of the second discharge light modules 4, respectively.

[0094] The two electrodes 5a, 5b, 6a, 6b of each pair of electrodes 5a, 5b, 6a, 6b are arranged in a distance a1, a2 from each other along the longitudinal direction A. The distances a1, a2 between the two electrodes 5a, 5b, 6a, 6b of each pair are measured between the centers C of the electrodes 5a, 5b, 6a, 6b along the longitudinal direction.

[0095] A first distance al between the electrodes 5a, 5b of the first pair of electrodes 5a, 5b, which are assigned to the first discharge light module 3, is smaller than a second distance a2 between the electrodes 6a, 6b of the second pairs of electrodes 6a, 6b, which are assigned to the second discharge light modules 4.

[0096] The first distance al between the electrodes 5a, 5b of the first pair of electrodes 5a, 5b may be between 3 mm and 7 mm, in particular between 4 mm and 6 mm, more particularly between 4.5 mm and 5.5 mm. The second distance a2 between the electrodes 6a, 6b of the second pairs of electrodes 6a, 6b may be between 6 mm and 14 mm, in particular between 8 mm and 12 mm, more particularly between 9.5 mm and 10 mm.

[0097] An electric voltage U, which exceeds a minimum ignition voltage Uign, may be applied to the two electrodes 5a, 5b, 6a, 6b of a pair of electrodes 5a, 5b, 6a, 6b for starting a gas discharge reaction, generating a light bow 12 within the at least one gas contained in the associated discharge light module 3, 4. The ignition voltage Uign is defined by the properties of the at least one gas within the discharge light modules 3, 4, and by the distance a1, a2 between the two electrodes 5a, 5b, 6a, 6b.

[0098] In a lighting device 2 according to an exemplary embodiment of the invention, as it is schematically depicted in FIG. 4, the distance al between the electrodes 5a, 5b of the first pair of electrodes 5a, 5b is smaller than the distances a2 between the electrodes 6a, 6b of the second pairs of electrodes 6a, 6b. In consequence, a first minimum ignition voltage Uign1, which is necessary for starting a gas discharge reaction generating a light bow 12 emitting electromagnetic radiation 14, in particular electromagnetic radiation 14 in the range of UV light, between the first electrodes 5a, 5b, which are assigned to the first discharge light module 3, is lower than a second minimum ignition voltage Uign2, which is necessary for starting a gas discharge reaction between the second electrodes 6a, 6b, which are assigned to the second discharge light modules 4.

[0099] In other words, a gas discharge reaction, generating a light bow 12 emitting electromagnetic radiation 14, can be started within the first discharge light module 3 by applying a first voltage U1≥Uign1 to the first pair of electrodes 5a, 5a, wherein the first minimum ignition voltage Uign1 is lower than the second minimum ignition voltage Uign2, which would be necessary for starting a gas discharge reaction between each of the second pairs of electrodes 6a, 6b, which are assigned to the second discharge light modules 4. Thus, when a first voltage Uign1≤U1≤Uign2 is applied to all electrodes 5a, 5b, 6a, 6b of the interior aircraft lighting device 2, a gas discharge reaction is started only between the first electrodes 5a, 5b assigned to the first discharge light module 3, as the first voltage U1 is not sufficient for starting a gas discharge reaction between the second electrodes 6a, 6b assigned to the second discharge light module 6.

[0100] However, when the at least one gas within a discharge light module 3, 4 is irradiated with electromagnetic radiation 14, in particular with electromagnetic radiation 14 including UV light, the gas molecules of the at least one gas are excited. As a result, the minimum ignition voltage Uign, which needs to be applied to the electrodes 5a, 5b, 6a, 6b for starting a gas discharge reaction, generating a light bow 12 within the at least one gas, is reduced.

[0101] After a gas discharge reaction in the first discharge light module 3 has been started, as it has been described before, a portion of the electromagnetic radiation 14, which is emitted by the light bow 12, generated by said gas discharge reaction, irradiates and excites molecules of the at least one gas within at least one of the second discharge light modules 4. The electromagnetic radiation 14 in particular irradiates and excites the gas molecules of the at least one gas with the second discharge light module 4, which is arranged next to the first discharge light module 3. This excitation of the gas molecules reduces the voltage Uign, which is necessary for starting a gas discharge reaction within said second discharge light module 4. In consequence, a gas discharge reaction within at least one second discharge light module 4, in particular within the second discharge light module 4, which is arranged next to the first discharge light module 3, may be started by applying the first voltage U1 to the second part of electrodes 6a, 6b, which are assigned to said second discharge light module 4, as well.

[0102] The electromagnetic radiation 14, emitted by the light bow 12 generated by the gas discharge reaction within said at least one second discharge light module 4, will excite the gas molecules in at least one further second discharge light modules 4. This excitation may allow for starting an additional gas discharge reaction within at least one further second discharge light modules 4, without increasing the voltage U applied to the electrodes 5a, 5b, 6a, 6b beyond the first voltage U1, which was applied to the first pair of electrodes 5a, 5b.

[0103] Thus, after a first gas discharge reaction has been started in the first discharge light module 3 by applying the first voltage U1 to the first pair of electrodes 5a, 5b, further gas discharge reactions in additional second discharge light modules 4 may be started by applying the same, relatively low, first voltage U1 to the electrodes 6a, 6b, assigned to said second discharge light modules 4, in a cascade or chain reaction, in which the gas molecules within at least one additional discharge light module 4 are excited by the electromagnetic radiation 14 emitted by the previously started discharge light modules 3, 4.

[0104] This cascade or chain reaction may allow for starting gas discharge reactions in all discharge light modules 4 by applying the first voltage U1 to all pairs of electrodes 5a, 5b, 6a, 6b. The first voltage U1 is lower than the second ignition voltage Uign2, which would be necessary for starting gas discharge reactions in the second discharge light modules 4 having electrodes 6a, 6b, which are spaced apart at the larger distance a2 from each other, if the gas molecules within the second discharge light modules 4 would not be excited by electromagnetic radiation 14.

[0105] As a result, the gas discharge reactions within all discharge light modules 3, 4 may be ignited by applying the lower first voltage U1 to the electrodes 5a, 5b, 6a, 6b. Thus, there is no need for applying a higher second voltage U2≥Uign2 to any of the pairs electrodes 5a, 5b, 6a, 6b for starting the gas discharge reactions. In consequence, an interior aircraft lighting device 2 according to an exemplary embodiment of the invention, as it is depicted in FIG. 4, may be ignited completely by applying the first voltage U1 which is lower than the second ignition voltage Uign2.

[0106] After all discharge light modules 3, 4 have been ignited, the power supply 10 may lower its output voltage to a voltage level sufficient for maintaining the emission of electromagnetic radiation from the discharge light modules 3, 4. In other words, the power supply 10 may lower its output voltage from a trigger voltage level, as described above, to a steady state operation voltage level. The voltage level for steady state operation may be below Uign1.

[0107] FIG. 5 depicts a schematic view of an interior aircraft lighting device 2 according to another exemplary embodiment of the invention.

[0108] The components of the interior aircraft lighting device 2 depicted in FIG. 5, which are analogous to the components of the interior aircraft lighting device 2 depicted in FIG. 4, are denoted with the same reference signs, and the analogous features will not be discussed in detail again. Reference is made to their description above.

[0109] The interior aircraft lighting device 2, schematically depicted in FIG. 5, differs from the interior aircraft lighting device 2, which is schematically depicted in FIG. 4, in that in the embodiment shown in FIG. 5, two pairs of electrodes 51a, 51b, 52a, 52b, in particular two first pairs of electrodes 51a, 51b, 52a, 52b, are assigned to the first discharge light module 3. In each of the two first pairs of electrodes 51a, 51b, 52a, 52b, the electrodes 51a, 51b, 52a, 52b are spaced apart from each other in a distance a11, a12, respectively, which is smaller then the second distance a2 between the two electrodes 6a, 6b, assigned to the second discharge light modules 4.

[0110] Each of the two first pairs of electrodes 51a, 51b, 52a, 52b comprises a first electrode 51a, 52a, which is electrically coupled to the first pole 11a of the electric power supply 10, and a second electrode 51b, 52b, which is electrically coupled to the second pole 11b of the electric power supply 10.

[0111] In consequence, gas discharge reactions, generating a light bow 12 between the two electrodes 51a, 51b, 52a, 52b of each first pair of electrodes 51a, 51b, 52a, 52b, may be started by applying a first voltage U1≥Uign1 to the electrodes 51a, 51b, 52a, 52b of the first pairs of electrodes 51a, 51b, 52a, 52b, respectively.

[0112] By starting two gas discharge reactions within the first discharge light module 3, two light bows 12 are generated. The generation of an additional light bow 12 results in the emission of additional electromagnetic radiation 14 from the first discharge light module 3. As a result, the amount of electromagnetic radiation 14, in particular electromagnetic radiation 14 including UV light, emitted from the first discharge light module 3 and, in consequence, also the amount of electromagnetic radiation 14 emitted from the interior aircraft lighting device 2, are increased. This results in an enhanced efficiency of the interior aircraft lighting device 2.

[0113] Similar to the embodiment depicted in FIG. 4, the electromagnetic radiation 14, emitted by the light bows 12 generated in the first discharge light module 3, excites gas molecules of the at least one gas within at least one of the second discharge light modules 4. This starts a cascade or chain reaction, which results in sequentially starting gas discharge reactions in all discharge light modules 3, 4, as it has been described before with respect to the embodiment depicted in FIG. 4.

[0114] In the exemplary embodiment depicted in FIG. 5, the distances a11, a12 between the two electrodes 51a, 51b, 52a, 52b of the two first pairs of electrodes 51a, 51b, 52a, 52b are identical. This, however, is only an exemplary configuration.

[0115] In an alternative configuration, which is not explicitly depicted in the figures, but which may also form an embodiment of the present invention, the first discharge light module 3 may be equipped with two pairs of electrodes 51a, 51b, 52a, 52b, wherein the distances a11, a12 between the electrodes 51a, 51b, 52a, 52b are different in each pair of electrodes 51a, 51b, 52a, 52b (a11≠a12).

[0116] In particular, the distance all of only one of the two pairs of electrodes 51a, 51b, 52a, 52b may be small enough for allowing a gas discharge reaction to be started by applying the relatively low voltage Uign1 to the electrodes 51a, 51b of said pair of electrodes 51a, 51b. The electromagnetic radiation 14, which is emitted by the light bow 12 generated by said gas discharge reaction, will support the starting of a further gas discharge reaction between the electrodes 52a, 52b of the other pair of electrodes 52a, 52b, which are provided at the first discharge light module 3, even if the distance a12 between the electrodes 52a, 52b of said other pair of electrodes 52a, 52b is larger and would require a higher voltage U≥Uign1 to be applied to the electrodes 52a, 52b for starting a gas discharge reaction in the absence of electromagnetic radiation 14.

[0117] Increasing the distance a12 between the electrodes 51a, 51b, 52a, 52b of a pair of electrodes 51a, 51b, 52a, 52b increases the length of the light bow 12, which is generated by the gas discharge reaction. In consequence, increasing the distance a12 between the electrodes 51a, 51b, 52a, 52b increases the amount of electromagnetic radiation 14 emitted by the first discharge light module 3.

[0118] It therefore might be beneficial to arrange only the electrodes 51a, 51b of a single first pair of electrodes 51a, 51b in a first (lower) distance from each other, in order to allow for starting a gas discharge reaction between these electrodes 51a, 51b by applying a first (lower) voltage U1≥Uign1 to these electrodes 51a, 51b, and to arrange the electrodes 52a, 52b, 6a, 6b of all other pairs of electrodes 52a, 52b, 6a, 6b in a larger distance a2>a1 from each other, in order to increase the total amount of electromagnetic radiation 14, which is emitted by the interior aircraft lighting device 2.

[0119] In the exemplary embodiments depicted in FIGS. 4 and 5, the electrodes 6a, 6b of all second pairs of electrodes 6a, 6b are arranged in the same distance a2 from each other. Although it is not explicitly shown in the figures, it is also possible that the distances a2 between the electrodes 6a, 6b of the second pairs of electrodes 6a, 6b are not the same in all second pairs of electrodes 6a, 6b. Instead, there may be at least one second pair of electrodes 6a, 6b, in which the distance a2 between the electrodes 6a, 6b is different.

[0120] In such a configuration, it is possible that the distances a2 between the electrodes 6a, 6b of the second pairs of electrodes 6a, 6b vary between the different discharge light modules 4. Alternatively or additionally, it is possible that two or more second pairs of electrodes 6a, 6b are assigned to at least some of the second discharge light modules 4. In such a configuration, the distances a2 between the electrodes 6a, 6b of said second pairs of electrodes 6a, 6b, which are assigned to the same second discharge light module 4, may be identical or different.

[0121] While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.