ILLUMINATION APPARATUS

Abstract

Non-emergency illumination apparatus (10) arranged in use to mark a location of an article, fixture or fitting in an aircraft cabin, the apparatus including: an emitting layer (2) including a photoluminescent material, the photoluminescent material emitting visible light in a first region of the electromagnetic spectrum in response to excitation by light from a second region of the electromagnetic spectrum, different to the first region; and a protective layer (6) overlying the emitting layer, the protective layer transmitting light from the first and second regions of the electromagnetic spectrum, wherein the non-emergency illumination apparatus is constructed and arranged to be placed in proximity to an article, fixture or fitting, such that the apparatus marks the location of the article, fixture or fitting when excited by light from the second region of the electromagnetic spectrum. The illumination apparatus can comprise a carrier matrix. The illumination apparatus aids location of items such as headphone sockets and power sockets in low lighting conditions so calming passengers.

Claims

1-33. (canceled)

34. A non-emergency illumination apparatus configured to mark a location of an article, fixture, or fitting in an aircraft cabin, the apparatus comprising: an emitting layer including a photoluminescent material, the photoluminescent material configured to emit visible light in a first region of the electromagnetic spectrum in response to excitation by light from a second region of the electromagnetic spectrum that differs from the first region; and a protective layer overlying the emitting layer, the protective layer transmitting light from the first and second regions of the electromagnetic spectrum; wherein the apparatus is configured to be placed in proximity to an article, fixture, or fitting, such that the apparatus marks the location of the article, fixture, or fitting when excited by light from the second region of the electromagnetic spectrum.

35. The apparatus of claim 34, wherein the light from the second region of the excitation spectrum is selected from the group consisting of: visible light; light from the violet or blue region of the visible spectrum; and light having a wavelength between 400 nm and 500 nm.

36. The apparatus of claim 34, wherein the photoluminescent material emits one of: visible light comprising green light; a range of wavelengths encompassing wavelengths which are close to wavelengths of maximum sensitivity of scotopic vision; or visible light including a range of wavelengths, with a maximum intensity at approximately 520 nm.

37. The apparatus of claim 34, wherein the emitting layer includes a matrix of a synthetic resin or polymeric structure, with the photoluminescent material distributed through the matrix.

38. The apparatus of claim 34, wherein the photoluminescent material comprises strontium aluminate and at least one material selected from the group consisting of SrAl.sub.2O.sub.4:Eu,Dy; SrAl.sub.4O.sub.7:Eu,Dy; SrAl.sub.12O.sub.19:Eu,Dy; Sr2Al.sub.6O.sub.11:Eu,Dy; Sr.sub.4Al.sub.2O.sub.7:Eu,Dy; Sr.sub.4Al.sub.14O.sub.25:Eu,Dy; and Sr.sub.7Al.sub.12O.sub.25Eu,Dy.

39. The apparatus of claim 38, wherein the photoluminescent material is selected to provide a performance of at least >50 mcd/m.sup.2 after 10 mins according to DIN67510.

40. The apparatus of claim 34, further including a second color layer, provided between the emitting layer and the protective layer, wherein, in first light conditions, the apparatus appears a first color from the emitting layer, and in second, different light conditions, the apparatus appears a second color, different from the first.

41. The apparatus of claim 40, wherein the second light conditions include light emitted from a third region of the electromagnetic spectrum, wherein the third region: includes and extends beyond at least the second region of the electromagnetic spectrum; or includes the UV portion of the electromagnetic spectrum.

42. The apparatus of claim 40, wherein the second lighting conditions are daylight or white light.

43. The apparatus of claim 34, further comprising indicia or markings formed by selective placement of the photoluminescent material or by patterning regions of the protective layer to be at least partially opaque to light in the first region of the electromagnetic spectrum.

44. The apparatus of claim 43, wherein printed or patterned areas of the indicia or markings block from 40% to 100% of light emitted by the photoluminescent material.

45. The apparatus of claim 34, further comprising a color modifier, wherein the color modifier is in the form of a film.

46. The apparatus of claim 34, further comprising a substrate, the emitting layer being mounted on the substrate.

47. The apparatus of claim 34, wherein the apparatus is configured to be provided on a face of an article, fixture, or fitting.

48. The apparatus of claim 34, wherein edges of the apparatus include a bezel shape.

49. The apparatus of claim 34, configured to be provided in a channel formed between an article, fixture, or fitting and an edge of a depression or aperture that is configured to receive the article.

50. The apparatus of claim 34, wherein the article, fixture, or fitting comprises at least one of: power socket or power socket surrounds; USB socket or USB socket surrounds; headphone sockets or headphone socket surrounds; seat numbers; seat edges; remote control identifiers; overhead bin trims; overhead bin handle locators; informational signage; light switches and call switches (for flight attendants); passenger Service Unit (PSU) informational signs; or PSU call buttons/light switches.

51. A method comprising using the non-emergency illumination apparatus of claim 34 to mark a location of an article, fixture, or fitting in an aircraft cabin.

52. The method of claim 51, wherein the illumination apparatus further comprises color film or a color modifier configured such that the illumination apparatus has a first appearance in a first light condition and is further configured to modify an appearance of the illumination apparatus in a second light condition different from the first light condition.

53. The method of claim 51, wherein the illumination apparatus further comprises a protective layer selected such that the performance of the apparatus is not reduced below 5 mcd/m.sup.2 after 10 mins.

54. The method of claim 51, further comprising retrofitting an aircraft with the non-emergency illumination apparatus.

55. A socket for use in an aircraft cabin, the socket comprising: a connector for connecting a piece of user equipment to a central system of the aircraft; and a non-emergency illumination apparatus according to claim 34 that is configured to illuminate the connector.

56. The socket of claim 55, wherein the connector is selected from the group consisting of a power outlet, a USB outlet, and a headphone socket.

57. The socket of claim 56, wherein the socket is located on a seating unit.

Description

[0081] Embodiments of the invention will now be described by way of example only, with reference to the drawings, in which:

[0082] FIG. 1 schematically illustrates a sectional view through a socket illumination apparatus;

[0083] FIG. 2 illustrates excitation curves and transmission curves for an example pigment and protective layer;

[0084] FIG. 3A illustrates an example of a power socket including a first embodiment of the socket illumination apparatus;

[0085] FIG. 3B illustrates an example of a USB socket including the first embodiment of the socket illumination apparatus;

[0086] FIG. 4A illustrates an example of a power socket including a second embodiment of the socket illumination apparatus;

[0087] FIG. 4B illustrates an example of a USB socket including the second embodiment of the socket illumination apparatus;

[0088] FIGS. 5A, 5B and 5C show application of the invention to a headphone socket, a remote control unit and a seat number; and

[0089] FIG. 6 shows application of the invention to a passenger service unit.

[0090] FIG. 1 illustrates a cross-section taken through the structure of a socket illumination apparatus 10. The apparatus 10 is a layered structure, including an emitting layer 2, which contains a photoluminescent material, a colour layer or film 4, and a protective top layer 6. The layers are joined by adhesive layers 3, 5. Any layers may comprise a single layer or multiple layers.

[0091] The photoluminescent material emits visible light in response to excitation (charging) by a different wavelength of light. The emitting layer 2 is a matrix formed by a synthetic resin or polymeric structure (for example a vinyl), with photoluminescent pigment distributed within the matrix.

[0092] The photoluminescent material may be excited by a single wavelength or a range of wavelengths from the electromagnetic spectrum. Similarly, it may emit a single wavelength or a range of wavelengths. The layers 3, 4, 5, 6 above the emitting layer 2 are configured to transmit the light required to excite the photoluminescent material, and to the light emitted. For example, the or each layer may be transparent or substantially transparent. The layers 3, 4, 5, 6 above the emitting layer may transmit all wavelengths required to excite the photoluminescent material, or only a sub-section of the wavelengths. Similarly, the layers 3, 4, 5, 6 above the emitting layer 2 may transmit all wavelengths emitted, or only a sub-section of the wave-lengths. If this is the case, the layers may act as a filter, altering the perceived colour of the apparatus 10.

[0093] The top layer of the layered structure is the protective layer 6 or protective topcoat. The protective layer provides a defence to stop the photoluminescent material being damaged in use. The protective layer 6 is also scratch resistant.

[0094] The protective layer 6 can be formed of any polymeric material with the required light transmission and scratch proof characteristics. For example, the protective layer may be a polycarbonate, polyester, polymethacrylate or polyurethane. The protective layer 6 can also be finished (e.g. polished) to provide a matt finish or gloss finish.

[0095] The intermediate colour film layer 4 is provided between the protective layer 6 and the emitting layer 2. The colour film layer 4 alters the colour the apparatus in different light conditions.

[0096] In normal lighting conditions, where the cabin is lit to approximate daylight (white light), the colour film provides a different colour appearance, from the ambient light reflecting from the colour film. The emission from the photoluminescent material may still be excited, but may be of low intensity compared to the light reflected by the colour film, such that the emission is negligible. As a result; the appearance of the film is determined by the reflective properties. Similarly, in low lighting conditions, the reflection from the film may be present, but low intensity compared to the emission, and so considered negligible and the appearance of the film is determined by the emitted light characteristics.

[0097] The emitting layer 2, colour film layer 4 and protective layer 6 all contribute to the appearance of the marker 10, and so may be considered functional layers. Adhesive layers 3, 5 are provided between the functional layers 2, 4, 6, to fix the structure together.

[0098] A further adhesive layer 1 is provided on the base of the structure, for attaching the layered structure to a substrate (not shown). The adhesive is not necessarily transparent, but may be. The adhesive layer may be opaque or partially opaque.

[0099] The apparatus can be used to illuminate a socket in low lighting conditions, for example, when an aircraft cabin is in night mode. The photoluminescent material is chosen to be excited by wavelengths of light that are still available in such an environment, and to emit light that is easily discernible to passengers. The layers 3, 4, 5, 6 above the photoluminescent material are chosen to transmit these wavelengths, so that the light necessary for charging, and the light emitted can pass through.

[0100] An example photoluminescent pigment that may be used is Strontium Aluminate (SrAl.sub.2O.sub.4) doped with Europium and Dysprosium. This emits green light with a peak emission at approximately 520 nm.

[0101] The dashed line in FIG. 2 shows the excitation curve 12 for this pigment (left hand y-axis). The excitation curve shows the spectrum of light that can be used to charge the pigment. The solid line in FIG. 2 shows the transmission curve 14 for the protective layer 6 (right hand y-axis). This shows the wavelengths of light that the protective layer 6 allows to pass through the protective layer. The adhesive layers 3, 5 and colour film layer 4 have similar transmission characteristics.

[0102] As can be seen from FIG. 2, the excitation curve 12 and transmission curve 14 overlap between approximately 400 nm and 500 nm. This means the pigment can be charged by light in this range. The transmission curve also allows the light emitted by the example pigment to pass at 520 nm. In other examples the overlap may be different. It is envisaged that in some embodiments the photoluminescent material may be charged by UV light.

[0103] The above pigment is just one example of a pigment that can be used. Any suitable pigment can be used, and the emission does not necessarily have to be green. In some examples, different strontium aluminates may be used. By varying the composition of the strontium aluminate (the ratio of strontium to aluminium to oxygen), different emission colour can be obtained. Other pigments that can be used as single pigments or as mixtures with each other or with (SrAl.sub.2O.sub.4) doped with Europium and Dysprosium include SrAl.sub.2O.sub.4:Eu,Dy; SrAl.sub.4O.sub.7:Eu,Dy; SrAl.sub.12O.sub.19:Eu,Dy; Sr.sub.2Al.sub.6O.sub.11:Eu,Dy; Sr.sub.4Al.sub.2O.sub.7:Eu,Dy; Sr.sub.4Al.sub.14O.sub.25:Eu,Dy; Sr.sub.7Al.sub.12O.sub.25Eu, Dy.

[0104] In general, it is preferable to keep the excitation between 400 nm and 500 nm, as these wavelengths are present in low lighting conditions, but other excitation wavelengths can be used. UV excitation wavelength may be used in some circumstances.

[0105] The colour film may be any suitable colour, and may be chosen to match or complement airline logos or liveries. The colour film may be plain or may be patterned.

[0106] The appearance of the apparatus 10 from above can be controlled, so that it shows markings or indicia, for example, logos, symbols or guidance about the orientation of sockets.

[0107] In one example, the markings or indicia can be applied by only providing the photoluminescent material in a chosen pattern. In other examples, the emitting layer 2 or protective layer 6 may be printed to be opaque to the excitation and/or emission wavelengths. This means that from above, the emission is only seen in a chosen pattern.

[0108] In some informational signs the information may be printed on the emitting layer or on the protective layer. Printed areas typically block some or all of the emitted light enabling the eye to differentiate between the printed and non-printed areas and to read the information provided or to identify the signage. Typically printed areas will block from 40 to 100% of the emitted light. In one embodiment the printed area will block around 90% of the emitted light.

[0109] The structure of the apparatus given above is by way of example only, and any suitable structure may be used.

[0110] The coloured film layer 4 is optional, and may be omitted. In this case, only a single adhesive layer 3, 5 is necessary.

[0111] The application of markings or indicia is also optional, and may be omitted.

[0112] The apparatus is made by forming the layered structure, in any suitable manner, and then cutting to the desired shape and size. The cutting may be by a die cutting tool. In some examples, this can give a bezeled shape at the edge, and forms a hard edge down the side of the layered structure, making it hard to access and tamper with or damage the apparatus 10, accidently or purposefully.

[0113] The apparatus 10 can be used to mark any suitable socket 20. For example, the socket 20 may be a power socket or a USB port that can be used for charging a passengers electronic devices. The power socket may be a universal socket, or a particular type of socket (three pin or two pin). In another example, the socket 20 may be a headphone socket for an in-flight entertainment system.

[0114] FIGS. 3A and 3B show examples of a power socket 20a and a USB socket 20b, with a socket illumination apparatus 10 provided around the edge of the socket 20. In general, the sockets are formed in seating units (not shown). The seating units include a depression or aperture to receive the socket 20, and a channel is formed between the socket 20 and the edge of the depression or aperture. The socket illumination apparatus 10 can be sized and shaped to fit into this channel.

[0115] In this case, the substrate may be the base of the channel. Alternatively, a separate substrate may be provided, and the apparatus 10 may be fixed in the channel by any suitable means. For example, the apparatus 10 may be fixed by a snap fit, or by mechanical fixing or by adhesive.

[0116] FIGS. 4A and 4B show alternative examples of a power socket 20a and a USB socket 20b. In this case, the apparatus 10 is provided on the face of the socket 20. Here, the bezel may be used to provide an aesthetically pleasing appearance. The bezel also forms a hard edge down the side of the layered structure, making it hard to access and tamper with or damage the apparatus 10, accidently or purposefully.

[0117] In this case, the face of the socket 20 may form the substrate, or the apparatus may have a separate substrate may be provided, and the apparatus 10 may be fixed in the channel by any suitable means. For example, the apparatus 10 may be fixed by a snap fit to the edge of the socket, or by mechanical fixing or by adhesive.

[0118] It will be appreciated that the use of the apparatus with sockets is by way of example only. The non-emergency illumination apparatus may be used with any article, fixture or fitting of an aircraft. FIG. 5A shows use of the illumination apparatus to mark the location of a headphone socket 30. FIG. 5B shows use of the illumination apparatus to mark the location of a remote control unit 40. FIG. 5C shows use of the illumination apparatus to mark the location of a seat number 50. Other applications and uses of the illumination apparatus will be apparent to those skilled in the art. For example, the illumination apparatus may be used to mark the location of no smoking signs on the PSU.

[0119] It will be appreciated that the illumination apparatus may be used instead of providing a lamp or other electrical light source behind the PSU buttons so saving on costs and weight in the aircraft. A combination of electrical and photoluminescent material may be utilised.

[0120] FIG. 6 shows an alternative use of the illumination apparatus on a PSU control panel. The illumination apparatus is used to mark the location of a light control switch 60. The illumination apparatus in this case comprises a decal fixed to the PSU over a switch for the reading light. The decal is has a colour film or filter to complement the colour of the PSU in the area generally indicated at 62 under daylight conditions and has a marking 64 indicating the function of the switch. In alternative embodiments the suitable pattern may be provided in a surface of the emitting layer. The decal emits light in low light conditions such that the location of the switch is clearly identified. The markings 64 may be arranged to be visible in low light conditions as well as in daylight.

[0121] The illumination apparatus 66 indicates a location of a cabin staff call button. The illumination apparatus comprises a decal with an area 68 arranged to have a colour under second lighting conditions (daylight or fully lit) that contrasts with the PSU and clearly identifies the location of the call button. Markings 70 identify the function of the call button. The markings 70 are additionally visible in the first lighting conditions (low light or dark). The decal for the call button may be arranged to emit a different colour light in the first lighting conditions compared to the light emitted by the decals for the reading lights.