Illuminated vehicle panel and method for manufacturing an illuminated vehicle panel

A method for manufacturing a panel includes forming a path segment on a surface of a substrate from a photoluminescent material. The method further includes overlaying the path segment with an overlay material. The overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

FIELD

This application generally relates to interior decorations of vehicles. In particular, this application describes an illuminated vehicle panel and a method for manufacturing an illuminated vehicle panel.

BACKGROUND

Airline operators may go to various lengths to improve brand recognition and customer experience. For example, in an effort to improve brand recognition, an operator may order aircraft from a manufacturer and specify in the order that the exterior of all aircraft ordered depict a logo or that all aircraft be painted a particular color. Specifying logos and colors may be especially true where the logo and/or colors have come to be associated with the operator.

In an effort to improve customer experience, the operator may specify that the interior of the aircraft be decorated in a pleasing manner and/or that the interior of the aircraft includes certain amenities desired by the operator's passengers. For example, the operator may specify the arrangement of the seats, the fabrics used throughout the cabin, and various colors and designs to depict within the aircraft.

SUMMARY

An example of a method for manufacturing a panel includes forming a path segment on a surface of a substrate from a photoluminescent material. The method further includes overlaying the path segment with an overlay material. The overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

An example of a panel for an interior cabin of an aircraft includes a substrate. A path segment is arranged on a surface of the substrate. The path segment is formed from a photoluminescent material. An overlay material is arranged on the path segment. The overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

An example of an aircraft includes a plurality of panels configured for attachment to an interior of a fuselage. At least one panel of the plurality of panels includes a substrate, a path segment, and an overlay material. The path segment is arranged on the surface of the substrate. The overlay material is arranged on the path segment. The overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

DETAILED DESCRIPTION

Various examples of systems, devices, and/or methods are described herein. Words such as “example” and “exemplary” that may be used herein are understood to mean “serving as an example, instance, or illustration.” Any implementation, and/or feature described herein as being an “example” or “exemplary” is not necessarily to be construed as preferred or advantageous over any other embodiment, implementation, and/or feature unless stated as such. Thus, other embodiments, implementations, and/or features may be utilized, and other changes may be made without departing from the scope of the subject matter presented herein.

Moreover, terms such as “substantially,” or “about” that may be used herein, are meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including, for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of ordinary skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

Introduction

As noted above, in an effort to improve customer experience, aircraft operators may specify that the interior of the aircraft be decorated in a particularly pleasing manner and/or that the interior of the aircraft include certain amenities. The examples disclosed herein describe a panel for the interior of an aircraft that includes photoluminescent graphics and a method for manufacturing the panels. While the examples herein are described in connection with aircraft, the examples can be applied to other types of vehicles such (e.g., cars, ships, trains). Additionally, the examples can be applied to non-vehicular structures such as signage, billboards, walls, etc. In some examples, the graphics correspond to asterisms and/or constellations. As used herein, the term asterism refers to a popularly known pattern or group of stars that can be seen in the night sky. The term constellation refers to a group of stars that forms an imaginary outline or pattern on the celestial sphere such as an animal, mythological person or creature, a god, or an inanimate object. In some other examples, the graphics can correspond to any shape or figure that passengers may find pleasing.

A combination of photoluminescent path segments arranged on the panel and illuminating openings formed therein can be utilized to depict the respective frames and stars of the asterisms and constellations. During the flight, the pilot or cabin attendant of the aircraft may dim the ambient lighting in the cabin and activate the illumination devices so that the asterisms and/or constellations become visible to the passengers. For example, the cabin attendant may press a button at a cabin attendant panel (CAP) of the aircraft, which may trigger an automated process of setting the cabin ambient lighting to the particular phase of flight at hand, for example, a sleep phase. A cabin services system (CSS) in communication with the CAP may communicate signals to the cabin lighting system of the aircraft to create a particular dynamic scene. As the cabin lights dim, the CSS may control the illumination devices to brighten, and the asterisms and/or constellations may subsequently become visible to the passengers.

The sudden appearance of the asterisms and/or constellations may give passengers a sense of wonder and improve the passenger experience. Additionally, rendering the asterisms and/or constellations visible during certain periods of the flight can be utilized to indicate the status of the flight. For example, the asterisms and/or constellations can be made visible when the aircraft is within one hour of landing. Passengers that frequently utilize the operator's aircraft may come to associate the rendering of the asterisms and/or constellations with the aircraft being close to its final destination.

FIG. 1Aillustrates an aircraft100.FIG. 1Billustrates an interior section of the aircraft, in accordance with an example. The aircraft100includes a plurality of panels105configured for attachment to an interior of a fuselage of the aircraft100. An example of the aircraft100can correspond to a large commercial passenger jet. The panels105can be arranged in a passenger section of the aircraft100. The panels105can be arranged on the ceiling and/or overhead compartments of the passenger section of the aircraft100. It should be noted that while the panels105are described herein in connection with a commercial passenger jet, examples of the panel can be adapted for use in other types of vehicles. For example, the panels can be utilized in buses, trains, and ships. The panels105can be used in other environments.

FIG. 2Aillustrates a more detailed rendering of a panel105that can correspond to one or more panels of the cabin of the aircraft100.FIG. 2Billustrates a side view of a portion of the panel105. Referring to the figures, the panel105includes a substrate205, a path segment210, and an overlay material215. The path segment210is arranged on a surface206of the substrate205. The path segment210is formed from a photoluminescent material. The overlay material215is arranged on the path segment210. The overlay material215is configured to render the path segment210substantially invisible under an ambient photopic condition (i.e., luminance levels of 10 to 108cd/m2) and render the path segment210visible under an ambient mesopic (i.e., luminance levels of 0.001 to 3 cd/m2) or scotopic condition (i.e., luminance levels of 10−3to 10−6cd/m2). The luminance levels above can correspond to the luminance levels measured in proximity to passenger seating, which can be measured by an optical power and wavelength meter manufactured by, for example, GL Optic. A different example of the overlay material215can be configured to render the path segment210substantially invisible under luminance levels different from those associated with the ambient photopic condition levels, and visible under luminance levels different from those associated with the ambient mesopic and/or scotopic conditions levels.

An example of the substrate205can correspond to a ridged material. For example, the substrate205can include a honeycomb core such as a Nomex® honeycomb core. The honeycomb core can be faced with, for example, one or two skin plies of glass/phenolic prepreg. In some implementations, the substrate205can be formed via a “Crush core” process. Such a process facilitates forming substrates having curved shapes and consistent thicknesses, which ensures a good fit and finish during installation. In this regard, an example of the substrate205can be formed to have a thickness, T, of about 0.5-inch thick, with a 0.12-inch cell size. An example of the substrate205can be formed to have dimensions of about be about 4 ft by 8 ft. An example of the substrate205can have a curved shaped configured to follow the contour of the interior of the cabin of the aircraft100. Other examples of the substrate205can be formed to have different thickness, dimensions and/or shapes.

As illustrated inFIG. 2C, in some examples, the substrate205can include a decorative film layer207, and the film layer207can be disposed over the face material of the substrate205. An example of the film layer207can include one or more layers of printed and/or textured films and a protective layer. Another example of the film layer207can correspond to a polyvinyl fluoride (PVF) film such as Tedlar®. The film layer207can be fixed to the substrate205with an adhesive such as an epoxy adhesive, a phenolic adhesive, or a polyurethane adhesive.

As noted above, the path segment210is arranged on the surface206of the substrate205. The path segment210is formed from a photoluminescent material. One example of the photoluminescent material can correspond to a phosphorescent material. Phosphorescent materials do not immediately discharge all the radiation they absorb. Rather, phosphorescent materials discharge radiation at a lower intensity for up to several hours after initial excitation. In this regard, one example of the path segment210can, for example, discharge radiation at a luminosity level of at least 0.041 cd/m2for at least 1 hour. These discharges can occur in different dominant emission wavelengths such as in the violet region (380-450 nm), the green blue region (490-560 nm), the blue region (450-450 nm), and the red region (635-700 nm) of the electromagnetic spectrum. In some examples, the discharges can occur in different emission wavelengths regions.

One example of the photoluminescent material can correspond to a mixture that includes strontium aluminate (SrAl2O4) and an adhesive such as a water based acrylic medium. One example of a water based acrylic medium includes a mixture of a gloss medium by Liquitex®, a varnish, and an alkyd. One example of the alkyd is a polyester resin such as Liquin® manufactured by Winsor & Newton®. In this regard, the photoluminescent material can discharge light in the 490-520 nm range. The wavelength can be measured using an optical power and wavelength meter manufactured by, for example, GL Optic. In some examples of the photoluminescent material, the chemistry can be altered so that the photoluminescent material discharges light in the violet range (<490 nm). For example, the chemistry can be altered by utilizing different phosphorescent materials in different combinations such as strontium, magnesium, calcium, barium, silicon, or titanium. In some cases, alkaline earth metals can be added with fluorescent pigments. Table 1 lists other example phosphor/dopant combinations from which the photoluminescent material can be derived along with the color of light discharged by each combination.

An example of the photoluminescent material can be configured to produce a particular luminosity level. In this regard, the photoluminescent material can correspond to a mixture that includes strontium aluminate, an adhesive, and a dopant. An example of the dopant can correspond to europium (Eu). The addition of the dopant facilitates trapping the photons in an excited state.

In some cases, the particle size of the photoluminescent material is selected to produce a particular luminosity. For example, a photoluminescent material having a large average particle size (e.g., >160 microns) can discharge light at a luminosity of about 0.25 cd/m2for at least 20 minutes. The particle size can be determined using, for example, a particle size analyzer (PSA) which can be configured to determine the particle size of a substance via high definition image processing, analysis of Brownian motion, gravitational settling of the particle and/or light scattering (Rayleigh and Mie scattering) of the particles. A photoluminescent material having small average particle size (e.g., 25 microns) can discharge light at a luminosity of about 0.10 cd/m2for at least 20 minutes.

In some instances, the thickness, T2, of the photoluminescent material can be selected to produce a particular luminosity level. For example, a nominal thickness, T2, of 300-400 microns can result in a photoluminescent material having a luminosity of greater than 0.4 cd/m2. A thicker layer of photoluminescent material can have a greater luminosity. Thus, the thicker the photoluminescent material, the easier it can be for a passenger to see a pattern formed from the photoluminescent material under a particular lighting condition in the aircraft cabin.

One issue with forming the path segment210from a material that includes SrAl2O4is that the path segment210can tend to have a pale yellow color in daylight. In this case, any shape defined by the path segment210can be slightly visible to the naked eye under ambient daylight conditions. The overlay material215discussed above can be arranged on the path segment210to mask and/or alleviate this issue.

The overlay material215is configured to facilitate the observation of light discharged from the path segment210under darkened conditions and to mask the pale yellow color of the path segment210under daylight conditions. More specifically, the overlay material215is configured to render the path segment210substantially invisible under an ambient photopic condition (i.e., luminance levels of 10 to 108cd/m2) and to render the path segment210visible under an ambient mesopic (i.e., luminance levels of 0.001 to 3 cd/m2) or scotopic condition (i.e., luminance levels of 10−3to 10−6cd/m2). In this regard, the overlay material215is further configured to allow blue wavelengths to pass through the overlay material215to facilitate charging the photoluminescent material, and to facilitate the discharge of, for example, blue or green emissions under ambient mesopic or scotopic conditions. One example of an overlay material215with these characteristics is a bandpass filter film such as a Delta continuously variable bandpass filter film.

As noted above, the overlay material215can be arranged on the path segment210. In some cases, an adhesive can be utilized to fix the overlay material215to the path segment210. An example of the overlay material215can have the same dimensions as the path segment210. For example, the overlay material215can have the same length and width as a particular path segment210covered by the overlay material215. In cases, where the sides of the path segment210can otherwise be exposed to ambient light, the overlay material215can be dimensioned to cover the entire surface of the path segment210and the sides of the path segment210so that no portion of the path segment210is directly exposed to ambient light.

An example of the panel105can include one or more openings220formed in the substrate205. The path segment210can linearly extend between a pair of openings220. An example of the opening220can extend through the entire substrate205. The opening220can have a circular shape, a square shape, or a different shape. In the case of a circular shape, in some example, the opening220can have a diameter, D, of about 1 mm (e.g., when a fiber optic cable is arranged in the opening). In a different example, the opening220can have a diameter, D, of 3-4 mm (e.g., when an LED is arranged in the opening).

FIG. 3Aillustrates an example of a panel105with an illumination device305arranged in an opening220of the substrate205of the panel105. The illumination devices305can help accentuate the intersections between path segments210, which in turn can allow a passenger to more easily identify a particular shape defined by the path segments210. The illumination device305is configured to emit light that then passes through the opening220. Examples of illumination devices305include light-emitting diodes (LEDs) and incandescent bulbs. While the illumination device305is illustrated as being within the opening220, in other examples of the panel105, the illumination device305can be arranged proximate to the opening220. For example, the illumination device305can be arranged below the substrate205or can protrude through the opening220to an extent.

The illumination device305can be electrically connected to a controller (not shown) configured to generate a voltage to power the illumination device305. An example of the controller can correspond to the above-referenced cabin services system (CSS). The controller can be configured to adjust the brightness of the illumination device305responsive to a command from the pilot of the aircraft100.

FIG. 3Billustrates an example of a panel105that utilizes a group of fiber optic cables315to optically distribute light emitted from an illumination device305to a group of openings220in the substrate205. For example, twenty fiber optic cables315can distribute light emitted from a single illumination device305to twenty different openings220. A different numbers of fiber optic cables315can distribute light emitted from one or more illumination devices305to a different number of openings220. The illumination device305can be arranged on or below a side of the substrate205opposite the path segment210. First ends312of the fiber optic cables315can be arranged in proximity to the illumination device305and second ends313of the fiber optic cables315can be arranged within or proximate to different openings220formed in the substrate205. In some examples of the panel, the illumination device305and the fiber optic cables315can be fixed to the bottom surface of the substrate205with, for example, an adhesive.

FIG. 3Cillustrates an example of a panel105that utilizes a light pipe310to optically distribute light emitted from an illumination device305to a group of openings220in the substrate205. For example, the light pipe310can define twenty different pathways. The pathways can distribute light emitted from a single illumination device305to twenty different openings220. The illumination device305can be arranged on or below a side of the substrate205opposite the path segment210. The light pipe310can have a first end317arranged in proximity to the illumination device305and one or more pipe terminals320arranged within or proximate to different openings220formed in the substrate205. In some examples of the panel, the illumination device305and the light pipe310can be fixed to the bottom surface of the substrate205with, for example, an adhesive.

In an example of the panel105, rather than forming openings in the substrate205, a circuit (not shown) that includes one or more illumination devices305(e.g., LEDs) can be printed on the top of the substrate205. Printing the circuit can be more cost effective than forming the openings. The illumination devices305can be arranged at locations corresponding to endpoints of the path segments210. The circuit can then be overlaid by the film layer207(e.g., Tedlar®), and light emitted from the illumination devices305can be seen through the film layer207. As noted above, illumination devices305can help accentuate the intersections between path segments210, which in turn can allow a passenger to more easily identify a particular shape defined by the path segments210.

Referring back toFIG. 2A, an example of the panel105can have a group of path segments210and openings220arranged in a recognizable shape. For example, the shape can correspond to an asterism (250and255) (i.e., a popularly known pattern or group of stars that can be seen in the night sky). Under darkened conditions, the openings220can be illuminated by the illumination device305to represent the stars of the asterism, and light emitted from photoluminescent material of the path segments210, arranged between the openings, can be visible. The combined illuminated openings220and visible path segments210depict the asterism (250and255). Within examples, the asterism250represents The Big Dipper and the asterism255represents The Little Dipper as illustrated inFIG. 2A. Other asterisms can be represented by various combinations of illuminated openings220and path segments210. A non-exhaustive list of internationally recognized asterisms that can be represented by particular arrangements of openings220and path segments210includes the Summer Triangle, the Great Square of Pegasus, the Sickle of Leo, the Diamond Ring, the Coathanger.

FIG. 4illustrates an example of a panel400depicting the shape of a constellation405. The constellation405corresponds to Ursa Major, as seen by the naked eye. Under darkened conditions, the openings220can be illuminated by the illumination device305to represent the stars of the constellation405and the light emitted from the photoluminescent material of the path segments210arranged between the openings can be visible. The combined illuminated openings220and visible path segments210depict the constellation405. Anon-exhaustive list of internationally recognized constellations405that can be represented by particular arrangements of openings220and path segments210includes Aquarius, Aquila, Aries, Canis Major, Cassiopeia, Cygnus, Gemini, Leo, Lyra, Ursa minor, Wheat of Virgo, and Orion.

In some cases, less well known but regionally significant constellations can be represented by particular arrangements of openings220and path segments210. For example, a non-exhaustive list of constellations405known to inhabitants of the islands of the Pacific that can be represented by particular arrangements of openings220and path segments210includes Ke Ka o Makali'i (“The Canoe-Bailer of Makali'i”), Iwikuamo'o (“Backbone”), Manaiakalani (“The Chief s Fishline”), and Ka Lupe o Kawelo (“The Kite of Kawelo”). Other constellations405known to inhabitants of other regions of the world can be represented. For example, constellations known to the inhabitants of Asia, Europe, and Africa can be represented.

In yet other examples, the substrate can include a plethora of openings220and the illumination devices305utilized to illuminate the openings220can be dynamically activated to show various combinations of patterns via the openings220. A computer can control the illumination devices305to activate according to, for example, a location of the aircraft, and predefined patterns.

As noted above, illuminated openings220and photoluminescent path segments210can be arranged in a myriad of patterns or any other image or shape to depict any shape or pattern. For example, the shape can correspond to a cartoon character. The shape can correspond to a company logo. The shape can correspond to a word or phrase. The shape can correspond to other images or shapes.

FIG. 5illustrates an example of a method for manufacturing the panel105ofFIG. 1B. Block500involves forming a path segment210on a surface206of a substrate205from a photoluminescent material, as illustrated inFIG. 6A.

The substrate205can correspond to a conformed rigid material such as a Nomex® honeycomb core. The honeycomb core can be faced with, for example, one or two skin plies of glass/phenolic prepreg. The substrate205can have a thickness, T, of about 0.5-inch thick, with a 0.12-inch cell size, and can have a surface area of about be about 4 ft by 8 ft. One or more layers of printed, textured, and/or protective film layers such as printed, textured, and/or protective film layers formed from a material such as Tedlar® can be attached to the substrate205with, for example, an adhesive.

An example of the photoluminescent material corresponds to a mixture that comprises strontium aluminate and an adhesive. A different example of the photoluminescent material can correspond to a mixture that comprises strontium aluminate, an adhesive, and a dopant. The photoluminescent material can, for example, discharge radiation at a luminosity level of at least 0.2 cd/m2for at least 30 minutes. The thickness, T2of the photoluminescent material can be selected to produce a desired luminosity level. For example, a thickness, T2, of 300-400 microns can result in a photoluminescent material having a luminosity of greater than 0.4 cd/m2. A thicker layer of photoluminescent material can have a greater luminosity.

An example of forming the path segment210involves a masking process. For example, a mask can be arranged on the surface206of the substrate205. The mask can define one or more cut-outs having particular shapes at locations associated with particular path segments210. For example, the shape of the cut-out (i.e., length and width) can match the length and width of a particular path segment210. An example of the mask can have a thickness that matches the desired thickness of the path segment210. For example, the thickness of the mask can correspond to the desired thickness, T2, of the path segment210.

After arranging the mask on the surface206of the substrate205, the photoluminescent material can be applied over the mask. In this regard, the photoluminescent can be in an uncured state. For example, the photoluminescent material can be in a liquid or gel state. The photoluminescent material can be spread evenly over the mask by a wiping operation.

After applying the photoluminescent material, the mask can be removed, and the photoluminescent material can be allowed to cure. Some examples of the photoluminescent material can cure in the presence of air or via a chemical reaction. The curing time of an example of the photoluminescent material can be reduced by heating the photoluminescent material. In some instances, the operations above can be repeated to build up successive layers of photoluminescent material to facilitate increasing the thickness of the photoluminescent material.

Another example for forming the path segment210involves depositing the photoluminescent material onto the surface206of the substrate205. For example, the photoluminescent material can be provided in a liquid state. The liquid photoluminescent material can be sprayed/printed onto the substrate205via a nozzle. The nozzle can be movable relative to the substrate205according to two degrees of freedom. In this regard, a computer can control the relative movement of the nozzle and the opening and closing of the nozzle to deposit the photoluminescent material. For example, the substrate205can be arranged on an X-Y table. The computer can control the X-Y table to move the substrate205under the nozzle and can control the nozzle to open and close in particular regions to form the path segments210on the substrate205.

Another example for forming the path segment210involves utilizing a printing process, such as a silkscreen printing process, for example, to apply the photoluminescent material to the substrate205. In silkscreen printing, an emulsion is spread over a screen and selectively cured with a negative of the desired pattern of the path segment210. The uncured parts of the emulsion are washed off the screen leaving openings in the mesh of the screen in locations corresponding to the path segment210. The photoluminescent material can then be spread on to the screen to fill the openings in the mesh of the screen associated with the path segment210. The screen can then be pressed onto the substrate205. Capillary pressure draws the photoluminescent material from the openings of the mesh to the surface206of the substrate205. The screen can then be removed, leaving behind photoluminescent material having a pattern of the path segment210. The photoluminescent material can then be cured (e.g., air dried, chemically cured, UV cured, etc.).

In some instances, the operations above can be repeated to build up successive layers of photoluminescent material to facilitate increasing the thickness of the photoluminescent material.

In the case of a panel105having a film layer207on the substrate205(SeeFIG. 2C), an example for forming the path segment210can involve utilizing any of the above techniques to form the path segment210on the film layer207of the substrate205before applying the film layer207to the substrate205. One example of this method involves providing the film layer207as a roll of film and utilizing a printer to deposit the photoluminescent material on to the roll of film. Afterward, the photoluminescent material can be cured as described above. The film roll can then be cut to a desired size and shape and applied to the substrate205, as described above.

Block505involves overlaying the path segment210with an overlay material215, as illustrated inFIG. 6B. As noted above, one issue with forming the path segment210from a photoluminescent material such as SrAl2O4is that the path segment210can tend to have a pale yellow color under an ambient photopic condition (i.e., luminance levels of 10 to 108cd/m2). The overlay material215is configured to render the path segment210substantially invisible under an ambient photopic condition and render the path segment210visible under an ambient mesopic or scotopic condition (i.e., luminance levels of 10−3to 10−6cd/m2).

One example of the overlay material215can correspond to the light enhancement film described above. In this case, the overlay material215can be configured to allow sufficient blue wavelengths to pass through the overlay material215to facilitate charging the photoluminescent material, and to facilitate viewing the discharge of blue or green emission from the photoluminescent material under in the mesopic or scotopic condition conditions.

The overlay material215can be cut into the shape of the path segment210so that the overlay material215has the same general dimensions as the path segment210. To prevent exposure of the edges of the path segment210to ambient light, the overlay material215can be dimensioned to cover the entire exposed surface of the path segment210so that no portion of the path segment210is directly exposed to ambient light.

After cutting the overlay material215into the desired shape, the shaped overlay material215can be fixed to the top of the path segment210. For example, the shaped overlay material215can be adhered to the top of the path segment210with an adhesive such as the water based acrylic medium described above.

Another example of the overlay material215can correspond to a thin layer of a translucent material having a color that matches the background of the panel105. For example, in the case of a panel105having a white background, the overlay material215can correspond to a white translucent material or a different color that, when combined with the pale yellow color of the photoluminescent material, renders the path segment210invisible to the naked eye under daylight conditions. The overlay material215can have a thickness smaller than 500 μm, smaller than 250 μm, and even smaller than 100 μm. The overlay material215can be applied to the path segment210by utilizing any of the depositing techniques described above. For example, the overlay material215can be applied over the path segment210via a masking process, deposition process, or a silkscreen process.

Block510involves forming openings220in the substrate205, as illustrated inFIG. 6C. Some examples for forming the openings220in the substrate205can involve drilling the openings220into the panel105with a drill bit or laser or forming the substrate205in a mold that defines the openings220in the substrate205. The openings220can extend through the entire substrate205. The openings220can have a circular shape, a square shape, or a different shape. In the case of a circular shape, in some example, the opening220can have a diameter, D, of about 1 mm (e.g., when a fiber optic cable is arranged in the opening). In a different example, the opening220can have a diameter, D, of 3-4 mm (e.g., when an LED is arranged in the opening).

Block515involves arranging an illumination device305within the openings220formed in the substrate205, as illustratedFIGS. 3A-3C. As noted above, the illumination device305can correspond to a light-emitting diode (LED) or an incandescent bulb. The illumination device305can be arranged within the opening220or proximate to the opening (e.g., just below the opening220, or protruding from the opening220). The illumination device305can be arranged on or below a side of the substrate205opposite the path segment210, and a light pipe310or fiber optic cable315can be utilized to optically distribute light emitted from the illumination device305to groups of openings220.

FIG. 7illustrates another example of a method for manufacturing a panel105. Block700involves forming a path segment210on a surface206of a substrate205from a photoluminescent material.

Block705involves overlaying the path segment210with an overlay material215, wherein the overlay material215is configured to render the path segment210substantially invisible under an ambient photopic condition and render the path segment210visible under an ambient mesopic or scotopic condition.

Some examples of the method can involve forming two or more openings220in the substrate205, wherein the path segment210linearly extends between a pair of the two or more openings220of the plurality of openings220; and arranging one or more illumination devices305in proximity to the two or more openings220to illuminate endpoints of the path segment210.

In some examples, arranging one or more illumination devices305can involve arranging a fiber optic cable315in proximity to the two or more openings220.

In some examples, arranging one or more illumination devices305can involve arranging a light-emitting diode (LED) in proximity to the two or more openings220.

Some examples of the method can involve arranging the two or more openings220in a shape of an asterism (250and255) or constellation405; and forming a plurality of path segments210between different pairs of openings220to thereby define a frame of the asterism (250and255) or constellation405.

In some examples of the method, forming the path segment210involves forming the path segment210on the surface206of the substrate205from a mixture that comprises strontium aluminate and an adhesive.

In some examples of the method, forming the path segment210involves forming the path segment210on the surface206of the substrate205from a mixture that comprises strontium aluminate, an adhesive, and a dopant.

In some examples of the method, overlaying the path segment210involves facilitating the charging of the photoluminescent material under the ambient photopic condition.

In some examples of the method, forming the path segment210on the surface206of the substrate205involves forming the path segment210on a face of a substrate205that includes a honeycomb core.

In some examples of the method, forming the path segment210on the surface206of the substrate205involves forming the path segment210on a surface of a polyvinyl fluoride (PVF) film.

In some examples of the method, forming the path segment210on the surface206of the substrate205involves depositing the photoluminescent material on the surface206of the substrate205

FIG. 8illustrates a method for illuminating an interior of a cabin of an aircraft100. Block800involves charging a photoluminescent material in a path segment210arranged on a surface of a panel105of the cabin during a first phase of a flight where an ambient light of the interior of the cabin corresponds to a photopic condition.

Block805involves changing the ambient light of the interior of the cabin to a mesopic or scotopic condition during a second phase of the flight, wherein during the second phase of the flight, emissions from the photoluminescent material of the path segment210are visible.

An example of the method can involve maintaining the ambient light of the interior of the cabin at the photopic condition so that the path segment210is rendered substantially invisible during the first phase of the flight.

An example of the method can involve rendering a frame of an asterism (250and255) or constellation405on the panel105visible during the second phase of the flight, wherein the frame of the asterism (250and255) is defined by a plurality of path segments210that include the photoluminescent material, and that extend between different pairs of a plurality of openings220on the panel105.

In some examples of the method, rendering the frame of the asterism (250and255) or the constellation405can involve illuminating an illumination device305arranged proximate to the plurality of openings220.

FIGS. 9A-11Fillustrate various views of example panels having illuminated path segments210arranged to depict various shapes. The shape depicted on the example panel ofFIGS. 9A-9Fcorresponds to the constellation Ursa Major. The shape depicted on the example panel ofFIGS. 10A-10Fcorresponds to the asterism Little Dipper. The shape depicted on the example panel ofFIGS. 11A-11Fcorresponds to the Big Dipper.

The path segments can be arranged on the panels differently. For example, the various shapes can be scaled, rotated, and/or offset to cover different areas of the respective panels. The shapes can be repeated on the respective panels. A combination of the shapes depicted on the various panels can be depicted on the same panel.

Moreover, the path segments can be arranged to show an entirely different shape. For example, path segments can be arranged to depict a combination of one or more of the internationally recognized constellations Aquarius, Aquila, Aries, Canis Major, Cassiopeia, Cygnus, Gemini, Leo, Lyra, Ursa minor, Wheat of Virgo, and Orion. Other internationally recognized constellations can be depicted. The path segments can be arranged to depict a combination of one or more of the regionally recognized constellations Ke Ka o Makali'i (“The Canoe-Bailer of Makali'i”), Iwikuamo'o (“Backbone”), Manaiakalani (“The Chief s Fishline”), and Ka Lupe o Kawelo (“The Kite of Kawelo”). Other constellations regionally recognized in different parts of the world can be depicted.

Further, the disclosure comprises embodiments according to the following clauses:

Clause 1. A method for manufacturing a panel, the method comprising: forming a path segment on a surface of a substrate from a photoluminescent material; and overlaying the path segment with an overlay material, wherein the overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

Clause 2. The method according to clause 1, further comprising: forming two or more openings in the substrate, wherein the path segment linearly extends between a pair of the two or more openings; and arranging one or more illumination devices in proximity to the two or more openings to illuminate endpoints of the path segment.

Clause 3. The method according to any of the proceeding clauses, wherein arranging one or more illumination devices comprises arranging a fiber optic cable in proximity to the two or more openings.

Clause 4. The method according to any of the proceeding clauses, wherein arranging one or more illumination devices comprises arranging a light-emitting diode (LED) in proximity to the two or more openings.

Clause 5. The method according to any of the proceeding clauses, further comprising: arranging the two or more openings in a shape of an asterism or constellation; and forming a plurality of path segments between different pairs of openings to thereby define a frame of the asterism or constellation.

Clause 6. The method according to any of the proceeding clauses, wherein forming the path segment comprises forming the path segment on the surface of the substrate from a mixture that comprises strontium aluminate and an adhesive.

Clause 7. The method according to any of the proceeding clauses, wherein forming the path segment comprises forming the path segment on the surface of the substrate from a mixture that comprises strontium aluminate, an adhesive, and a dopant.

Clause 8. The method according to any of the proceeding clauses, wherein overlaying the path segment comprises facilitating charging of the photoluminescent material under the ambient photopic condition.

Clause 9. The method according to any of the proceeding clauses, wherein forming the path segment on the surface of the substrate comprises forming the path segment on a face of a substrate that includes a honeycomb core.

Clause 10. The method according to any of the proceeding clauses, wherein forming the path segment on the surface of the substrate comprises forming the path segment on a surface of a polyvinyl fluoride (PVF) film.

Clause 11. The method according to any of the proceeding clauses, wherein forming the path segment comprises: depositing the photoluminescent material on the surface of the substrate.

Clause 12. A panel for an interior cabin of an aircraft, the panel comprising: a substrate; a path segment arranged on a surface of the substrate, the path segment formed from a photoluminescent material; and an overlay material arranged on the path segment, wherein the overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

Clause 13. The panel according to clause 12, further comprising: two or more openings formed in the substrate, wherein the path segment corresponds to a linearly that extends between a pair of the two or more openings; and one or more illumination devices arranged in proximity to the two or more openings to illuminate endpoints of the path segment.

Clause 14. The panel according to any of the preceding clauses starting from clause 12, wherein at least some of the one or more illumination devices correspond to a fiber optic cable.

Clause 15. The panel according to any of the preceding clauses starting from clause 12, wherein at least some of the one or more illumination devices correspond to a light-emitting diode (LED).

Clause 16. The panel according to any of the preceding clauses starting from clause 12, wherein the two or more openings are arranged to define a shape of an asterism or a constellation, wherein the panel further comprises a plurality of path segments, formed from the photoluminescent material, between different pairs of openings to thereby form a frame of the asterism or the constellation.

Clause 17. The panel according to any of the preceding clauses starting from clause 12, wherein the photoluminescent material comprises a mixture of strontium aluminate and an adhesive.

Clause 18. A vehicle that corresponds to an aircraft comprising: a plurality of panels configured for attachment to an interior of a fuselage, wherein at least one panel of the plurality of panels comprises: a substrate having a surface; a path segment arranged on the surface of the substrate, the path segment formed from a photoluminescent material; and an overlay material arranged on the path segment, wherein the overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

Clause 19. A vehicle that corresponds to a bus comprising: a plurality of panels configured for attachment to an interior of the bus, wherein at least one panel of the plurality of panels comprises: a substrate having a surface; a path segment arranged on the surface of the substrate, the path segment formed from a photoluminescent material; and an overlay material arranged on the path segment, wherein the overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

Clause 20. A vehicle that corresponds to a train comprising: a plurality of panels configured for attachment to an interior of the train, wherein at least one panel of the plurality of panels comprises: a substrate having a surface; a path segment arranged on the surface of the substrate, the path segment formed from a photoluminescent material; and an overlay material arranged on the path segment, wherein the overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

Clause 21. A vehicle that corresponds to an automobile comprising: a plurality of panels configured for attachment to an interior of the automobile, wherein at least one panel of the plurality of panels comprises: a substrate having a surface; a path segment arranged on the surface of the substrate, the path segment formed from a photoluminescent material; and an overlay material arranged on the path segment, wherein the overlay material is configured to render the path segment substantially invisible under an ambient photopic condition and render the path segment visible under an ambient mesopic or scotopic condition.

Clause 24. The vehicle according to the any of preceding clauses from clause 18, further comprising: two or more openings formed in the substrate, wherein the path segment corresponds to a linearly that extends between a pair of the two or more openings; and one or more illumination devices arranged in proximity to the two or more openings to illuminate endpoints of the path segment.

Clause 25. The vehicle according to the any of preceding clauses from clause 18, wherein at least some of the one or more illumination devices correspond to a fiber optic cable.

Clause 26. The vehicle according to the any of preceding clauses from clause 18, wherein at least some of the one or more illumination devices correspond to a light-emitting diode (LED).

Clause 27. The vehicle according to the any of preceding clauses from clause 18, wherein the two or more openings are arranged to define a shape of an asterism or a constellation, wherein the panel further comprises a plurality of path segments, formed from the photoluminescent material, between different pairs of openings to thereby form a frame of the asterism or the constellation.

Clause 28. The vehicle according to the any of preceding clauses from clause 18, wherein the photoluminescent material comprises a mixture of strontium aluminate and an adhesive.

While the systems and methods of operation have been described with reference to certain examples, it will be understood by those skilled in the art that various changes can be made and equivalents can be substituted without departing from the scope of the claims. Therefore, it is intended that the present methods and systems not be limited to the particular example disclosed, but that the disclosed methods and systems include all embodiments falling within the scope of the appended claims.