Multilayer structure with embedded light source and light guiding features and method of making the same

Abstract

The present disclosure relates to multilayer structures having embedded light sources and light-guiding features and methods for making the same. An integrated multilayer structure includes: a substrate film having a first side and an opposing second side; an electronic device including at least one light source disposed on the first side of the substrate film, the at least one light source being configured to emit light at one or more selected frequencies or wavelengths; an optically transmissive element comprising a thermoplastic material that is optically transmissive with respect to the selected frequencies or wavelengths; and an optical cladding comprising a material having a refractive index lower than the first refractive index and disposed adjacent to the optically transmissive element on the first side of the substrate film, wherein the at least one light source, the optically transmissive element, and the optical cladding are configured relative to each other to transmit light emitted by the light source within the optically transmissive material of the optically transmissive element, with at least a portion of the transmitted light undergoing total internal reflection when incident on the optical cladding.

Description

[0001] This application is a divisional application of the Chinese national phase application of the PCT application with an application date of December 5, 2019, an international application number of PCT / FI2019 / 050872, and an invention name of “Multi-layer structure with embedded light source and light-guiding features and its manufacturing method”. The application number of the Chinese national phase application is 201980074617.9, and the national phase entry date is May 12, 2021. The entire content is incorporated herein by reference. Technical Field

[0002] The present invention generally relates to multi-layer structures related to electronic devices, associated housings and structures, and methods of manufacture. In particular, but not exclusively, the present invention relates to providing an integrated lighting solution within a multi-layer structure. Background Art

[0003] In the context of electronic devices and electronic products, such as various electronic devices, for example, there are generally a variety of different stacked assemblies and structures.

[0004] The motivations behind stacking electronic devices and other components in a common structure can be as diverse as the associated use contexts. When the resulting optimized solution ultimately exhibits multi-layer properties, it is relatively common to seek size savings, weight savings, cost savings, usability benefits, or simply efficient integration of components, for example, in terms of manufacturing processes or logistics. Related use scenarios can then involve product packaging or food boxes, the visual design of device housings, wearable electronic devices, personal electronic devices, displays, detectors or sensors, vehicle interiors, antennas, signs, vehicles, and especially automotive electronics, etc.

[0005] Electronic devices such as electronic components, ICs (integrated circuits) and conductors can generally be placed on substrate elements by a variety of different techniques. For example, off-the-shelf electronic devices such as various surface mount devices (SMDs) can be mounted on the surface of a substrate that ultimately forms the inner or outer interface layer of a multilayer structure. In addition, technologies that fall under the term "printed electronics" can be applied to actually produce electronic devices directly and additively onto an associated substrate. The term "printing" in this context refers to various printing technologies that can produce electronic devices / electrical components from printed matter by essentially additive printing processes, including but not limited to screen printing, flexographic printing and inkjet printing. The substrate used can be an organic flexible printing material, however this is not always the case.

[0006] Substrates such as plastic substrate films can be subjected to processing such as (thermo) forming or molding. In practice, a plastic layer can be provided on the film using, for example, injection molding or casting, and then potentially embedded with many elements such as electronic components present on the film. The plastic layer can have different mechanical, optical, electrical, thermal and other properties. The obtained multilayer structure or stacked structure can be configured for various purposes according to the features included in, for example, the electronic device, as well as the expected use scenario and the relevant use environment. For example, the obtained multilayer structure or stacked structure can include connection features for coupling with compatible features of the container or the overall container structure, or vice versa.

[0007] However, the concept of injection molded structural electronic devices (IMSE) actually involves building functional devices and their parts in the form of multilayer structures, and the multilayer structures typically encapsulate electronic functions as seamlessly as possible. The characteristic of IMSE is that the electronic device is usually (not always) manufactured into a real 3D (non-planar) form according to the 3D model of the entire target product, partial design or overall design. In order to realize the desired 3D layout of the electronic device on a 3D substrate and in the associated final product, the electronic device can still be arranged on an initially flat substrate such as a film using a two-dimensional (2D) electronic device assembly method. Therefore, the substrate that has accommodated the electronic device can be formed into a desired three-dimensional, i.e., 3D shape and, for example, overmolded by a suitable plastic material, the suitable plastic material covers and is embedded with underlying components such as electronic devices, thereby protecting and potentially hiding the components from environmental influences. Additionally or alternatively, a 3D assembly of electronic devices can be used.

[0008] Sometimes, different components, surfaces, or devices, such as those composed of or including IMSE structures, should be equipped with lighting capabilities that can carry decorative / aesthetic or functional purposes, such as guidance or instructional purposes. For example, the environment of a component or device should be floodlit to increase visibility in dim or dark conditions at night. This, in turn, can enable various human activities that typically require a relatively high level of lighting comfort, such as walking or reading, to be carried out smoothly. Alternatively, lighting can be used to warn or inform different parties about the status of, for example, a housing component or a connected remote device, through different warning or indicator lights. However, lighting can give a housing component a desired appearance and visually emphasize certain features of the component by, for example, setting a desired color on brighter areas of the component. Therefore, lighting can also be used to guide the user of the device regarding the location of different functional features on the device surface, such as buttons, switches, touch-sensitive areas, or the actual functions underlying the illuminated features.

[0009] Therefore, there are a variety of use cases for lighting in conjunction with different IMSE structures and devices. However, since lighting may not always be the highest priority or most important key feature or the only feature in the associated product, and lighting is at least sometimes considered only a supplementary, optional feature, the design and implementation of lighting features that provide the desired lighting effects should be appropriately performed. Weight and size requirements, increased power consumption, additional design considerations, new process steps, and increased overall complexity of the manufacturing phase and the resulting product are examples of many disadvantages that can easily manifest as side effects of employing suboptimal lighting features in the target solution. However, the appearance and, for example, perceptibility of the lighting effect of the lighting element is another issue. In some applications, the light source should remain hidden or minimally exposed, or the lighting effect should avoid easily identifiable hot spots.

[0010] Optically, many solutions that generally achieve their goals in terms of light transmission or lighting performance in the context of IMSE still include problems including light leakage, crosstalk, and transmission losses (attenuation), which may be due to incoherent scattering and absorption, among other reasons. Summary of the Invention

[0011] It is an object of the present invention to at least alleviate one or more of the above-mentioned disadvantages associated with existing solutions in the context of various electronic devices or other housing elements provided with lighting features.

[0012] Said objects are achieved by embodiments of the multilayer structure and related manufacturing methods according to the present invention.According to one aspect and preferred embodiment of the present invention, an integrated multilayer structure comprises a substrate film having a first side and an opposing second side;

[0013] an electronic device comprising at least one light source, optionally an LED, disposed on said first side of said substrate film and advantageously comprising a number of electrical conductors at least electrically coupled to said at least one light source, said at least one light source being configured to emit light at a selected frequency or frequencies / bands or corresponding wavelength or wavelengths (the skilled person will naturally recognize a certain direct inverse relationship between the two, frequency x wavelength = light rate), optionally including or in some embodiments limited to all or selected wavelengths of visible light;

[0014] an optically transmissive element comprising a thermoplastic material that is optically transmissive with respect to said selected frequency or wavelength(s), said optically transmissive thermoplastic material having a first refractive index and preferably produced by moulding from said optically transmissive thermoplastic material onto at least said first side of said substrate film so as to at least partially embed said at least one light source therein; and

[0015] an optical cladding comprising a material having a refractive index lower than the first refractive index and disposed on the first side of the substrate film adjacent the optically transmissive element;

[0016] wherein the at least one light source, the optically transmissive element and the optical cladding have been configured with respect to one another to transmit light emitted by the light source within the optically transmissive material of the optically transmissive element, at least a portion of the transmitted light undergoing substantially total internal reflection upon being incident on the optical cladding.

[0017] For example, the cladding may be positioned adjacent the optically transmissive element such that the cladding contacts and borders the optically transmissive element at least in places (locally, if not in most or substantially every place) at its periphery.

[0018] In a preferred embodiment, the at least one light source, the transmissive element, and the cladding are aligned with one another so that at least about 30% or 50%, more preferably at least about 75%, even more preferably at least about 90%, and most preferably substantially all, of the light emitted by the source (e.g., at least at a frequency / wavelength of interest, such as visible light) and entering the transmissive element advantageously reaches the interface between the transmissive element and the cladding at least the first time at an angle (i.e., the angle defined by arcsin (refractive index of the cladding / refractive index of the transmissive element)) that exceeds the critical angle between the transmissive element and the cladding. Thus, the portion of the light that reaches the interface at angles greater than the critical angle of interest is substantially completely reflected. In this context, the critical angle of incidence is measured relative to the surface normal.

[0019] However, in some embodiments, several membranes or in particular substrate membranes may be arranged in the structure; for example, there may be at least one membrane on each side of the cladding.

[0020] In various supplementary or alternative embodiments, in addition to or instead of at least one mounted light source such as a surface mount component type light source (e.g., an LED), the at least one light source includes one or more light sources such as OLEDs (organic LEDs) that have been additionally produced such as printed directly on a substrate film so as to exhibit a desired shape in terms of physical appearance such as size and / or its light emission pattern.

[0021] Thus, a plurality of elements arranged in the multilayer structure are typically produced at least partially additively by printed electronics technology, for example with reference to the at least one light source, the one or more electrical conductors and / or the cladding.

[0022] In various additional or alternative embodiments, the cladding has been configured, in terms of the relevant material, to be substantially optically transparent with respect to a selected frequency or wavelength.

[0023] In at least some additional or alternative embodiments, the optical cladding is formed from several physically separate or connected (integral) layers and / or elements, typically preferably with at least a portion of the optically transmissive element therebetween, wherein two or more layers of the cladding optionally extend at least partially substantially parallel to the surface of the substrate film. Additionally or alternatively, the cladding may extend at least partially laterally relative to the substrate film, for example, when the cladding contacts and / or conforms to one or more component shapes or one or more shapes of the transmissive element. A layer, piece, or entire cladding may be substantially planar, or the cladding may be three-dimensional and conform to, for example, the shape of the substrate, the transmissive element, and / or other adjacent layers and / or the shape of the component.

[0024] In various embodiments, the cladding can thus establish at least one adjacent and preferably also physically contacting layer with respect to the transmissive element in any direction relative to the transmissive element. As also repeated elsewhere herein, the actual orientation of the multilayer structure in use may vary depending on the usage scenario, but if the multilayer structure is considered to be a structure in which the substrate film is positioned below the transmissive element, the cladding can be provided below the transmissive element, i.e., between the substrate film and the transmissive element. Additionally or alternatively, at least a portion of the cladding can be provided on one side of the transmissive element (next to the transmissive element) and / or on top of the transmissive element. The cladding can include portions such as being at least partially parallel to or conforming to, for example, a layer of the substrate film. However, the cladding can include portions such as being at least partially perpendicular to the substrate film and / or parallel to or conforming to, for example, one or more sides of the transmissive element. Thus, the cladding can be considered to form at least a portion of one or more reflective walls of a plurality of optical channels having the transmissive element as the internal optically transmissive core within the multilayer structure.

[0025] In various still additional or alternative embodiments, the optical cladding comprises

[0026] at least one layer between the substrate film and the transmissive element, the at least one layer preferably being in contact with either the film or the transmissive element; and

[0027] At least one further layer on the opposite side of the transmissive element relative to the substrate film, the at least one further layer preferably being in contact with the transmissive element and / or being located between the transmissive element and an optional light blocking element. Features of potential light blocking elements are discussed in more detail below.

[0028] However, the optical cladding may comprise a plurality of lateral portions, such as side walls, which may optionally connect the at least one layer and at least one other layer, whereby the cladding covers the transmissive element at least in places potentially from substantially all directions.

[0029] In various supplementary or alternative embodiments, the substrate film at least partially includes at least one element selected from the group consisting of: optically transparent material, transmissive material, translucent material, opaque volume, transparent volume, translucent volume, transmissive volume, opaque material, opaque coating, translucent coating, optically absorbing material, optically absorbing coating, absorbing area, light scattering material, scattering area, light scattering coating, reflective material, reflective coating, color film, color coating, color pigment, color dye, luminescent material, printed layer, ink, colored ink, graphic pattern and graphic design.

[0030] In various supplementary or alternative embodiments, the structure further comprises an optionally substantially opaque light absorbing or scattering element, the optionally substantially opaque light absorbing or scattering element optionally being located substantially between the substrate film and the optically transmissive element. The light absorbing or scattering element may exhibit at least one selected color, the at least one selected color optionally being provided by a color pigment, color dye, color coating, or color film included in the element. The light absorbing or scattering element may have been printed or otherwise produced onto the substrate film or positioned on the substrate film, for example, as an off-the-shelf element.

[0031] In various supplementary or alternative embodiments, the structure further comprises at least one additional film on the optically transmissive element, the at least one additional film being on an opposite side of the optically transmissive element relative to the side facing the substrate film. The additional film may optionally house or be at least adjacent to at least a portion of the optical cladding. When housing one or more other elements such as cladding, other optical features, or electronic devices, the additional film may be considered an additional substrate film in terms of its functionality.

[0032] The additional film at least partially includes at one or more places at least one element selected from the group consisting of: optically transparent material, transmissive material, translucent material, opaque volume, transparent volume, translucent volume, transmissive volume, opaque material, opaque coating, translucent coating, optically absorbing material, optically absorbing coating, absorbing region, light scattering material, scattering region, light scattering coating, reflective material, reflective coating, colored film, colored coating, colored pigment, colored dye, luminescent material, printed layer, ink, colored ink, graphic pattern, graphic design, electrical element (e.g., conductive traces, electrodes, contact pads) and electronic components.

[0033] In various complementary or alternative embodiments, at least one light exit element may already be arranged in the structure, preferably adjacent to the optical transmission element, for outcoupling light transmitted within the transmission element and incident on the exit element. Thus, in addition to outcoupling light from the transmission element, one or more light exit elements may also enable or at least participate in outcoupling light from the overall multilayer structure, for example, into the structure's surroundings. For example, one or more exit elements may be additively produced, subtractively produced, and / or implemented by omitting at least a portion of one or more selected features, such as cladding material, from a target surface, for example, from a surface of a substrate film, a transmission element, or another film.

[0034] The light exit element may include at least one element selected from the group consisting of: a through hole defined in the optical cladding and defined by the material of the optical cladding for allowing the transmitted light incident on the optical cladding to pass therethrough; a surface relief structure; a grating structure; a prismatic structure; a cladding-free region or volume between the substrate film and the optically transmissive element onto which the transmitted light is incident; an optically mask-free region or volume between the transmissive element and the surface of the structure; a refractive outcoupling element; a diffractive outcoupling element; an outcoupling element comprising an optically transmissive material that is substantially optically transmissive with respect to a frequency or frequency band, optionally translucent or substantially transparent, optionally exhibiting one or more selected colors; and an outcoupling element comprising an optically transmissive material having a refractive index similar to or higher than the first refractive index.

[0035] The components listed above can be flexibly and selectively combined, as will be understood by those skilled in the art, to provide the desired light-emitting element for each embodiment of the multilayer structure. For example, the formed through-hole can be provided with a selected filling material / outcoupling element having a refractive index higher than the second refractive index, preferably even higher than the first refractive index.

[0036] In various supplementary or alternative embodiments, a substantially opaque, optionally reflective, absorptive, or scattering optical blocking element has been positioned substantially adjacent to the optically transmissive element and / or the optical cladding in the multilayer structure. The blocking element may define, for example, at least a portion of a light transmission, leakage, and / or crosstalk limiting masking structure such as an optical channel partition or support structure within the overall structure. The blocking element may be configured to substantially cover or interface with the transmissive element and / or the optical cladding, at least selectively, in a surface and / or lateral direction of the substrate film.

[0037] The skilled person will further recognize that the individual elements discussed herein, each having associated therewith certain functions, such as light scattering or light emission, can also be cleverly combined into a common element or structure. For example, a film, for example, which is color-coated or more thoroughly tinted, can be provided with through-holes or substantially transparent windows filled with another material. Thus, a common element can produce several effects in a spatially separate manner. Alternatively, for example, a scattering material can be applied in the holes, since it still allows light to pass through to a sufficient degree, thereby achieving a combined scattering and emission element. Thus, even substantially the same area or volume of an element can implement multiple desired functions. However, a blocking element or blocking function can be implemented in a common element or structure, and thus specifically even in exactly the same part or position of the common element or structure, together with or in fact by the absorbing and / or scattering element or function.

[0038] As will be appreciated by the skilled person, many of the various elements of the multilayer structure, such as the substrate film, the optional additional films, the cladding, the blocking elements, the transmitting elements, the absorbing or scattering elements and / or the light exit elements, and potentially the entire multilayer structure, may at least partially exhibit a non-planar three-dimensional shape, with reference to, for example, locally curved or angled shapes. Alternatively, one or more substantially flat films, one or more selected other layers and / or the overall structure may be preferred and thus configured.

[0039] For the sake of completeness and in any case for clarity, it should be noted that in some embodiments, the multilayer structure may contain a number of additional elements that may be identical, similar, or more significantly different from the elements discussed herein in terms of structure, function, and / or other aspects such as positioning or relative configuration. For example, the multilayer structure or, in particular, the substrate film therein may be provided with one or more additional light sources, which, however, are not embedded in the material of the transmissive element or optically connected to the transmissive element in a manner consistent with the at least one light source discussed in detail herein.

[0040] According to another aspect and preferred embodiment of the present invention, there may be provided a method of establishing an integrated multi-layer structure, the method comprising:

[0041] obtaining a substrate film configured to house an electronic device on at least a first side thereof, the substrate film having the first side and a second side;

[0042] providing an electronic device comprising at least one light source, such as an LED, which is optionally printable or mountable, on said first side of said substrate film and a number of electrical conductors connected to said at least one light source, preferably by printed electronics technology; and

[0043] An optically transmissive element is preferably established onto the first side of the substrate film by molding or casting and thereby at least partially embedding the at least one light source, the transmissive element being established from an optically at least translucent, preferably transparent, thermoplastic material having a first refractive index, wherein an optical cladding such as one or more cladding layers is optionally established by printing, dipping, spraying the substrate film and / or at least partially together with the substrate film to be located adjacent to the optically transmissive element on the first side of the substrate film, the optical cladding comprising a material having a refractive index lower than the first refractive index.

[0044] In some embodiments, at least a portion of an element, such as at least a portion of a transmissive element, can be disposed on the second side of the substrate film, optionally by further manufacturing steps such as a molding step and / or by utilizing openings such as cutouts or through-holes in the substrate film, which openings enable molten and / or flowing plastic material used to form the transmissive element to flow between the sides of the substrate film and to build up the desired structure on both sides. Thus, electronic devices such as one or more light sources, other components, optical elements and / or conductors can be disposed on the second side and optionally at least selectively embedded in the overmolded or generally over-applied plastic of the transmissive element.

[0045] In various embodiments, the optical cladding can be, for example, selectively disposed on one or more areas on the first side of the substrate film, optionally with the substrate film potentially omitting the positions of one or more elements already disposed or to be disposed on the substrate film before the one or more selected elements are disposed on the substrate film, such as the position of at least one element selected from the group consisting of: the at least one light source, the electrical conductor, and the light absorbing or scattering area or element.

[0046] On the other hand, the optical cladding can be provided essentially non-selectively on the first side of the substrate film, which optionally already houses at least one element selected from the group consisting of: the at least one light source, an electrical conductor, a light exit element, and a light absorbing or scattering region or element. Optionally, a temporary masking element can be initially provided on or next to the at least one element or other location on the substrate film and removed after providing the optical cladding. The cladding can still be provided both selectively and non-selectively. For example, some layers or portions of the cladding can be provided non-selectively, while the remaining layers can be provided selectively.

[0047] In various embodiments, the adjacent optical cladding may be provided in several steps and / or layers, preferably, at least one layer of the optical cladding being provided before at least a portion of the transmission element such that the transmission element at least partially covers at least one underlying layer on the substrate film; and / or at least one other layer of the cladding being provided after providing the at least a portion of the transmission element and thereby being located next to (on the side of) and / or on top of the at least a portion of the transmission element.

[0048] In some embodiments, the method may include providing a light blocking element made of a substantially opaque material to at least the first side of the substrate film, preferably by molding substantially adjacent to the transmitting element and / or the optical cladding, optionally next to and / or on top of the transmitting element and / or the optical cladding. The blocking element can be configured to substantially cover the transmitting element and / or the optical cladding from one or more selected directions, such as the sides or the top. The blocking element can thus contact the cladding, but preferably, the cladding remains between the transmitting element and the blocking element, at least in the area where the transmitting element should retain light emitted by the one or more light sources. The blocking element can have properties that satisfy a masking function, an insulating function, a structural rigidity, or other structural property enhancement function in the multilayer structure.

[0049] However, in various supplementary or alternative embodiments, the method may incorporate at least one action selected from the group consisting of:

[0050] - providing at least one further film on the substrate film or more particularly on the transmissive element, wherein the at least one further film optionally houses a number of patterns, electrical conductors, electrodes and / or electronic or other components (e.g. one or more further light sources such as LEDs and / or associated control circuitry);

[0051] - providing said substrate film, said further film or other layer of said multilayer structure with at least one optical element, optionally a substantially opaque optical scattering or absorbing element, optionally incorporating removal of said masking element therefrom after providing a cladding material also ending up on a temporary masking element;

[0052] - providing the optical cladding in several steps and layers, optionally before providing at least a portion of the transmissive element on the substrate film and / or after providing said at least a portion of the transmissive element;

[0053] - providing a light exit element optionally adjacent to (e.g. in contact with) or at least optically connected to the optically transmissive element, e.g. at or at least partially defined by the substrate film and / or the further film; and

[0054] - forming the substrate film and / or the further film, optionally hot-forming or cold-forming, to assume a target three-dimensional shape, preferably after providing at least one element, such as an electrical conductor or an electronic component, such as the light source, on the substrate film and / or the further film.

[0055] In various embodiments of the method, the at least one further film may comprise a film provided on a side of the transmissive element opposite to the side facing the substrate film.The further film may optionally house or be at least adjacent to at least a portion of the optical cladding.

[0056] A device, such as an electronic device, may be provided that includes an embodiment of the multilayer structure. The device may be a portable, handheld, wearable, desktop, or other type of device. For example, the device may be a standalone device, or the device may be part of a larger integrated body with respect to a dashboard panel, door panel, roof panel, other panel, seat, or other feature of a vehicle. The device may be a lighting device or may primarily perform some other function of, optionally, a vehicle or some other target device. However, embodiments of the method according to the present invention may include one or more stages involving mounting or directly producing a multilayer structure according to an embodiment of the present invention onto a containing device or containing structure.

[0057] As the skilled person understands, the different considerations presented herein with respect to the embodiments of the multilayer structure may be flexibly applied mutatis mutandis to the embodiments of the method, and vice versa.

[0058] The utility of the present invention, according to embodiments, arises from a number of problems.

[0059] For example, and again naturally depending on the specific embodiment of the multilayer structure or method being considered, various compact, lightweight, highly integrated, and optically efficient lighting devices, as well as many other devices, components, or structures that still incorporate electronics and lighting-related optical features, can be achieved by utilizing the proposed multilayer construction and associated manufacturing methods. Because the resulting structures can exhibit a relatively simple and compact design, these properties translate into durability and other additional beneficial assets in many usage scenarios. The relative simplicity of the associated manufacturing process itself yields its own benefits, with reference to, for example, fairly tolerable equipment and material costs, space, processing time, logistics and storage requirements, and high overall production yields.

[0060] In various embodiments, the propagation of light, at least at selected frequencies / wavelengths, is achieved or enhanced by utilizing embodiments of the proposed optical cladding within the discussed multilayer structure, e.g., at the periphery of a light-guiding function, having a transmissive element. The transmissive element can, in turn, be positioned between at least one, typically embedded, light source and a destination (target) element, zone, or region in the structure, such as a specific exit element or other portion of the structure that defines an exit region / surface toward, e.g., the environment and one or more potential users of the structure residing therein. The cladding material is selected to have a sufficiently low refractive index to ensure a sufficiently small critical angle between the transmissive element and the cladding, which generally translates into an increased amount of totally internally reflected light in the transmissive element->cladding direction at the interface of interest.

[0061] However, since the cladding can be conveniently positioned between various additional elements and a transmissive layer made of, for example, molded plastic to more effectively retain light within the transmissive layer, the use of various additional elements, such as blocking elements or color-rendering elements (e.g., colored films / coatings), in the structure is facilitated, which would otherwise easily cause light losses, such as in the form of undesirable light scattering, absorption, or leakage. Otherwise, i.e., without the cladding between the additional elements and the transmissive layer, more light may escape first from the transmissive light-guiding element to the additional elements and from there to, for example, the environment. For example, the critical angle at the interface of interest (if any) (the additional elements may even have a higher refractive index than the primary transmissive element) can be smaller than the critical angle at a direct interface between the transmissive element and the environment (e.g., air). However, leakage phenomena can also be exploited by selectively omitting, for example, the cladding from locations where it is desired that light outcoupling from the transmissive element occur, such as through a colored element or some other element. The cladding can also be omitted where the transmission element is in direct contact with, for example, the air present in the environment, since air has a very low refractive index of 1 and therefore generally functions quite well as a dynamic "cladding".

[0062] In various embodiments, the cladding may be substantially optically transparent with respect to, for example, visible light or other selected frequencies / wavelengths or alternatively exhibit at least one selected color.Thus, for example, the cladding may have at least limited optical masking functionality associated therewith.

[0063] Nevertheless, also in connection with the introduction of similarly described claddings and the increased applicability of blocking / masking elements or, in particular, colored elements in combination with, for example, multilayer structures based on IMSEs, flexible positioning of light sources is facilitated in the structure, which further makes designing such structures generally more convenient by increasing the associated design freedom. Thus, in various embodiments, the positioning of light sources such as LEDs and embedded electronic devices in general is relaxed, taking into account the actual housing of the multilayer structure and / or its environment. The desired light path, optical efficiency, and other preferred optical (if not strictly lighting-related) properties can be obtained not only by positioning and aligning the light source and the transmissive material, but can also be obtained jointly by configuring the cladding and potential other optical functional elements such as light exit elements, absorption or scattering elements, optical microstructures, etc. as desired in the multilayer structure. Preferred lighting properties can include, for example, enhanced controllability of light uniformity at desired locations such as selected light exit surfaces of the structure. For example, with respect to such surfaces, illumination uniformity can be improved. However, for example, different highly conformable light transmitting channels established by one or more transmissive elements and associated claddings may be provided in a variety of 3D shapes, thereby well following and adapting to the shape of the overall multilayer structure when desired.

[0064] In general, by determining various characteristics of the structure, such as the cladding material, the size and positioning of the cladding, desired optical properties in terms of, for example, transmittance, reflectivity, absorbance or absorptivity, scattering properties, etc., can be achieved and even locally controlled spatially flexibly but accurately in the structure. Thus, the optical efficiency of the structure can be improved or otherwise optimized, either globally or locally.

[0065] In various embodiments, a number of lighting features, such as light sources and associated optics, guiding layers or, in particular, light-transmitting transmissive layers and, preferably, low optical loss-inducing layers, cladding layers, lenses, diffusers, collimators, prisms, diffractive elements, reflectors, opaque / masking elements, etc., can be cleverly integrated into a common assembly, which in turn can create at least a portion of a containment device or containment element. Even within a common embodiment, different types of light sources can be provided, for example, in terms of output characteristics (wavelength / frequency, point-sampled versus area-sourced), power consumption, size, or manufacturing techniques (e.g., printing and mounting). For example, one or more lighting effects can be created with aesthetic / decorative, instructive, instructional, and / or warning components. By appropriately configuring the light source, intermediate elements such as transmissive elements, blocking / colored elements, and, for example, associated exit regions or elements, the outcoupled light can appear very uniform, while still being able to utilize various masking or blocking functions to conceal underlying electronics, such as light sources, conductors, control circuitry, or other embedded features from external viewers, such as users of the structure.

[0066] Finally, in addition to lighting aspects, the resulting structure can also present a selected appearance or, for example, tactile sensation to a viewer, such as a human operator, through a selected configuration of surface graphics, embedded graphics, surface materials with different surface profiles (look and feel), overall shape, etc. The materials used can be optimized for various purposes, including, for example, protection, optics, vision, adhesion, durability, and electrical aspects. For example, the material of the transmissive element, as well as other used materials such as film materials or other layered materials, can be optionally selected to protect embedded components, such as electronic devices, from various environmental conditions, such as moisture, heat, cold, dust, vibration, etc.

[0067] The expression "a number" herein may refer to any positive integer starting from one (1).

[0068] The expression "plurality" may accordingly refer to any positive integer starting from two (2).

[0069] Unless explicitly stated otherwise, ordinal numbers such as “first” and “second” are used herein to distinguish one element from other elements and do not specifically prioritize or rank the elements.

[0070] Different embodiments of the invention are disclosed in the appended dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Next, the present invention will be described in more detail with reference to the accompanying drawings, in which:

[0072] Figure 1 An embodiment of the multilayer structure according to the invention is illustrated by means of a relative side view or a cross-sectional side view.

[0073] Figure 2 Shown Figure 1 A variation of the embodiment of FIG.

[0074] Figure 3 Additional variations are shown.

[0075] Figure 4 Still further variations are shown.

[0076] Figure 5 is a flow chart disclosing an embodiment of a method according to the invention.

[0077] Figure 6 The use scenario of the multilayer structure according to the embodiment of the present invention is presented, and the multilayer structure can flexibly and selectively adopt, for example, Figures 1 to 4 any one of the characteristics of .

[0078] Figure 7 An embodiment of a multi-layer structure incorporating multiple light channels according to the present invention is depicted through a pseudo-planar view. DETAILED DESCRIPTION

[0079] As will be appreciated by those skilled in the art, and again depending on each specific embodiment, the various material layers of the present invention, and generally elements such as the transmissive element, the cladding, one or more films, the absorbing or scattering element (e.g., a colored film), the light-blocking element, and / or the light-exiting element, can extend in multiple dimensions within and / or on the multilayer structure, i.e., the element can have a significant width, length, and height, wherein the height or "thickness" can be measured, for example, in a transverse direction relative to a plane defined, at least in part, by the surface of the substrate film. However, the width, length, and height can be considered to be perpendicular to one another, so that the individual positions of the element can be conveniently defined in three-dimensional Euclidean space, for example, by Cartesian coordinates. For example, the substrate film or the transmissive element often locally or generally defines a substantially planar or only slightly curved and / or elongated shape, and thus, due to the negligible height compared to the remaining dimensions, the element of interest can generally be considered to be substantially two-dimensional, but other more radically substantially three-dimensional overall shapes are also possible in the context of the present invention.

[0080] The materials of the various elements described herein, such as those discussed above, can have different properties, as the elements can be, for example, flexible, elastic, hard, or rigid, and therefore the resulting elements and multilayer structures as a whole can also exhibit such properties at least partially (if not generally).

[0081] In various embodiments of the present invention, one or more materials that can optionally be used as one or more films as substrates for various electronic devices such as light sources, control and / or sensing (e.g., touch or environmental sensing) circuit systems and / or for other elements such as the various optical elements discussed may include at least one material selected from the group consisting of: polymers, thermoplastic materials, organic materials, elastomeric materials, electrically insulating materials, PMMA (polymethyl methacrylate), polycarbonate (PC), polyimide, copolymers of methyl methacrylate and styrene (MS resin), glass, organic materials, fibrous materials, polyethylene terephthalate (PET), metal, wood, solid wood, veneer, plywood, bark, treebark, birch bark, cork, natural leather, natural textiles or fabric materials, textile materials, cotton, wool, linen, silk, formable materials, thermoformable materials, and cold-formable materials.

[0082] In various embodiments, one or more materials of the optical transmitting element, the optical cladding, the optical exit element and / or the optical blocking element contained in the structure may further include, for example, at least one material selected from the group consisting of: polymers, thermoplastic materials, elastic materials, electrically insulating materials, PC, PMMA, ABS, PET, nylon (PA, polyamide), polypropylene (PP), polystyrene (GPPS) and MS resin.

[0083] In various embodiments, in addition to, for example, a number of light sources and associated electrical conductors such as additionally printed traces and / or contact pads, the multilayer structure can be provided with at least one further electrical or electronic component comprising at least one element selected from the group consisting of: an integrated circuit, a processing unit, a memory, a communication unit, a transceiver, a transmitter, a receiver, a signal processor, a microcontroller, a battery, a light sensing device, a photodiode, a connector, an electrical connector, an optical connector, a power connector, a diode, a printed electronic component, a sensor, a force sensor, a touch sensor, a proximity sensor, an antenna, an inertial sensor, an accelerometer, a gyroscope, a capacitive switch or sensor, an inductive sensor, a user interface element, a vibration element, an electrode, a sensor electrode, a printed sensor electrode, a wireless tag, an electronic subassembly, and a photovoltaic cell. For example, the component can be initially provided on one or more films of the structure.

[0084] Generally, in various embodiments, the power supply for any component housed by the multilayer structure, such as one or more light sources or control / processing devices, can be provided at least in part by an included battery or other locally located power source. However, in order to distribute appropriate power from the power source to the numerous electrical components, or specifically electronic components, contained in the multilayer structure, specialized power circuitry, including, for example, one or more converters, can be utilized. A number of electrical conductors can be used for power delivery and communication between the various components.

[0085] Alternatively or additionally, the power connection and / or the communication connection can be arranged to the multilayer structure via at least one connection element such as an electrical (contact-based) connector, which is arranged via a compatible external connector of, for example, an external device or an external system such as a housing device of the multilayer structure and / or via a wireless or contactless connection such as one or more inductive or capacitive connection elements provided in the form of, for example, conductive loops or, in particular, coils, which are preferably located at the surface of the structure or at least functionally accessible via the surface of the structure.

[0086] Please refer to the attached drawings for details. Figure 1 At 100 one embodiment of a multilayer structure or assembly according to the present invention is shown.

[0087] For the sake of clarity, the depicted, still merely exemplary, structure 100 is shown as exhibiting a relatively flat overall shape. However, as contemplated above, one skilled in the art will appreciate the fact that the optimal shape can be determined on a case-by-case basis based on, for example, optical, structural, dimensional, and aesthetic design objectives. Thus, in addition to or in lieu of substantially planar surfaces, the resulting overall shape and / or the constituent shapes of the included elements can also be more thoroughly three-dimensional, thereby at least partially incorporating, for example, curved or angled portions. However, the finer-scale surface texture of structure 100 can be constant or vary spatially. The texture can contain, for example, flat and / or granular portions due to, for example, the material used or the type of surface microstructure, such as an optical microstructure provided to the surface layer.

[0088] The structure 100 is provided with at least one substrate 102, preferably of the film or "foil" type, and therefore generally having a considerable width and / or length compared to its thickness (vertical direction in the figure). The substrate film 102 may contain, for example, a plastic material, optionally a thermoplastic material. The substrate film 102 may be at least substantially insulating where it is present (if not completely electrically insulating). The substrate film 102 may be flexible, for example bendable, so that it may conform to and assume different target shapes, such as curved shapes, at least in regions (if not in its entirety), without breaking in the final structure 100. However, the film 102 may be elastic.

[0089] In some embodiments, structure 100 may establish itself as a complete functional integration, while in other embodiments, structure 100 may be physically and / or operationally connected (e.g., in terms of potential wireless communication and / or power delivery) to another structure, such as a container.

[0090] The substrate film 102 houses electronic devices on at least one side thereof (referred to as "first" in the figure) and on a corresponding surface thereof, the electronic devices including at least one light source 110 such as an LED, as discussed above. However, the substrate film 102 can be configured to house a number of additional electrical components or, in particular, electronic components and / or components of a different nature, such as optical components, on the same or opposite ("second") side.

[0091] In some embodiments, the opposite second side of the film 102 can define at least a portion of the exterior of the structure, but it can also be covered by many additional elements or layers. However, in some embodiments, the multilayer structure 100 can be attached to a containing structure via the film 102. For example, the second side of the film 102 can be utilized as a contact side or specifically as a contact surface for accommodating or receiving many specific connecting elements such as rivets, screws, adhesives, pins, nails, bosses, boss bases or their counterparts. Alternatively or in addition, in the depicted example, substantially any one of the side walls of the structure 100 (shown as vertical) or, for example, the top surface of the optically transmissive element 104 on the opposite side relative to the film 102 can be similarly used to secure the structure.

[0092] As discussed above, a number of electrical conductors 112 or "lines" may already be provided to supply power from an internal or external power source to electronic devices such as one or more light sources 110. However, there may be conductors 112 used to transmit signals (e.g., control signals and / or (other) data) between different elements of the onboard electronics, i.e., the electronics contained in the structure 100, and / or between the electronics contained in the structure 100 and external devices or structures. The same conductors 112 may even be used for both power and data communication.

[0093] The optical cladding 106 may have been arranged on the substrate film 102 to cooperate with the optically transmissive element 104, wherein the transmissive element 104 preferably comprises a thermoplastic material such as contemplated elsewhere herein.

[0094] The transmissive element 104 is configured to transmit the light emitted by the at least one light source 110 and therefore has suitable transmission characteristics, such as transmittance, for such purpose at wavelengths / frequencies of interest, optionally including or limited to visible light and / or other selected wavelengths emitted by the light source 110. Thus, the element 104 can be considered to functionally establish the transmissive core of a light guide or light guide structure, which can further be referred to as a light channel. The shape of the element 104 can be selected specifically based on the use case, for example from the perspective of the manufacturing technology used, such as injection molding. In some embodiments, the transmissive element 104 can refer to a multi-part element, which optionally includes several physically unconnected (but still potentially, for example, optically connected) transmissive (sub-) elements. On the other hand, sub-elements or, for example, protrusions or other parts of a substantially unitary or monolithic transmissive element 104 can be configured to establish multiple light channels within a multi-layer structure.

[0095] In various embodiments, the cladding 106 can include one or more interconnected and / or unconnected cladding elements or portions, such as layers that are optionally spatially distributed substantially in a plane and / or in three dimensions at selected locations within the structure 100. Thus, the cladding 106 can be arranged so as to create several component layers that preferably have at least partially at least a portion of the optically transmissive element 104 therebetween. Two or more of such layers can optionally extend at least partially substantially parallel to the surface and / or lateral direction of the substrate film 102.

[0096] Therefore, instead of or in addition to the cladding 106 being located on the substrate film 102, a portion of the cladding 106 may be provided elsewhere, such as on the opposite side of the transmissive element 104 relative to the substrate film 102 or the light source 110. Figure 1 106 on top of the structure shown. As discussed in more detail elsewhere herein, the opposite side of the transmissive element 104 may also optionally contain a film that may be configured to initially receive or at least later abut at least a portion, such as a layer, of the cladding 106. However, such an additional film is not required to provide the cladding 106 on the opposite side of the element 104, as the cladding 106 may be suitably printed, sprayed, or, for example, transfer laminated to the element 104.

[0097] In some embodiments, the cladding material 106 can be disposed on a substrate film 102 that already houses electronic devices such as a light source 110. Thus, the light source 110 can be at least partially covered from the side and / or top by the cladding material, as shown at optical cladding 106a. In such a scenario, at least the light-emitting surface of the light source 110 (e.g., the light source can be side-emitting or top-emitting) protected by temporary masking during the application of the cladding 106 can be subsequently removed, for example, mechanically or chemically. Alternatively, the material and overall configuration of the cladding 106 covering the light source 110 can be appropriately selected so that even after the application of the cladding 106, light output by the source 110 still reaches the transmissive element 102 to a desired degree. For example, the material and geometry at the light source 110-cladding 106 interface can be selected so that light passing from the light source 110 into the transmissive element 104 is not reflected back to the light source 110 nor is it significantly attenuated in the cladding 106. For example, the refractive index of the optical device of the light source 110 can be selected to be lower than the refractive index of the cladding 106, or the optical device can be adjusted so that the emitted light is incident on the surface of the cladding 106 at one or more incident angles less than the critical angle of interest, such as an incident angle close to zero (relative to the surface normal).

[0098] In general, the desired total transmittance at the wavelengths of interest may naturally vary depending on the specific embodiment being implemented, but typically, the plastic material used to construct, for example, the transmissive element 104 comprises a material that is substantially optically transparent or translucent with respect to the selected frequencies or wavelengths, thereby enabling the frequencies / wavelengths to pass through the material with sufficiently low losses. Thus, a sufficient total transmittance of the transmissive element 104 at the relevant wavelengths may vary depending on the embodiment, but may be, for example, about 50%, 60%, 70%, 75%, 85%, 90%, or 95% or more.

[0099] Structure 100 is preferably configured to at least partially enable propagation of light emitted by the at least one light source 110 within transmissive element 104 based on internal reflection, preferably substantially total internal reflection. Therefore, element 104 preferably comprises one or more materials having a higher refractive index than the adjacent cladding 106. Potentially, by finer tuning of associated material properties, such as the concentrations of constituent species, light propagation, including the reflection-to-outcoupling ratio, can be spatially selectively controlled within the structure, and even within a single element, in terms of, for example, refractive index. Large differences in the interfacing materials of transmissive element 104 and cladding 106 at an inspected location can translate into increased amounts of reflected light at that location due to a smaller critical angle, and vice versa. Thus, both global and local tuning of light reflection and transmission properties at a transmissive element-to-cladding interface can be achieved, for example, by varying the material of the transmissive element, the material of the cladding, and / or by omitting the cladding.

[0100] Preferably, the refractive index of at least the main material of the cladding 106 is about 1.4 or less. If the transmissive element 104 essentially comprises, for example, PMMA or PC, the refractive index of the element 104 is therefore about 1.48 or 1.55, respectively.

[0101] Preferably, the thickness of the cladding 106 is selected, at least in certain locations, to be sufficient to allow or enhance TIR-based propagation of light within the adjacent transmissive element 104. As a generally applicable rule of thumb, the thickness may be approximately at least about twice the wavelength of the TIR-propagating light in the element 104. When considering visible light, such a minimum thickness may be about 1.5 μm. This is to avoid, for example, evanescent wave coupling (frustrated TIR) that may occur through the cladding 106.

[0102] In view of the foregoing, the relative positions, sizes, and shapes or geometries of the transmissive element 104, the one or more light sources 110, such as top- or side-emitting LEDs, and the cladding 106 can be configured such that light emitted by the one or more light sources 110, after propagating within the transmissive element 104, reaches (at least to a degree deemed sufficient) a selected material interface, such as the 104-106 interface, at an angle greater than the associated critical angle to ensure that light incident at the interface within the transmissive element 104 is internally reflected and thus continues to propagate rather than entering adjacent materials, thereby naturally eliminating one or more potential special locations where alternative phenomena, such as light outcoupling, transmission, absorption, and / or scattering, are desired and designed to occur and are therefore desired to occur at least to a limited extent. It may still be preferred, for example, that even a small portion of the light that reaches such a special location continues to propagate within the transmissive element 104 due to partial reflection until, for example, the next special location is encountered.

[0103] In some embodiments, the transmissive element 104 and at least one additional element, such as the substrate film 102, are configured to have substantially similar optical properties, such as, for example, refractive index, at least partially. The interface between the transmissive element and the at least one additional element can then be considered transparent or substantially non-existent with respect to incident light and, for example, total internal reflection-based propagation of the incident light in a light-guiding combination of the type of functional polymerization of the element of interest. In addition to or in lieu of the substrate film 102, the at least one additional element can include one or more other elements, such as additional films, that can also be included in the structure.

[0104] The multilayer structure 100 may generally indeed comprise a number of individual further elements, such as (colored) films and / or (substrate) films, (colored) printed layers or other layers of material, for example adjacent to the cladding, which may be understood to mean beside the cladding 106 in a common plane therewith, and which are also in contact with the transmitting element 104 or, for example, shielded by / behind the intermediate cladding 106 from the perspective of the transmitting element 104. As mentioned above, such further elements may have properties, such as a refractive index, which may result in more light leaving the transmitting element 104 if they are arranged in direct contact with the element 104 rather than with the cladding 106.

[0105] For example, item 108 refers to a light extraction element, which is preferably positioned adjacent to the transmission element 104, and optionally in contact with the transmission element to promote outcoupling of light from the transmission element. The light extraction element 108 can be configured to pass incident light through for outcoupling purposes and / or reflect the light in a manner, such as at one or more selected angles, so that the light will more easily exit the transmission element the next time it reaches the periphery of the transmission element 104, such as the element 104->cladding 106 interface. However, the light extraction element 108 can be configured to promote partial outcoupling and partial continuous transmission (within the element 104) of the incident light.

[0106] The light exit element 108 may therefore include, for example, at least one element selected from the group consisting of: a through hole defined in the optical cladding and defined by the material of the optical cladding for enabling the transmitted light incident on the optical cladding to pass therethrough; a surface relief structure; a grating structure; a prismatic structure; an unclad region or volume between the substrate film and the optically transmissive element into which the transmitted light is incident; a refractive outcoupling element; a diffractive outcoupling element; an outcoupling element comprising an optically transmissive material that is optically substantially transmissive with respect to a frequency or frequency band, optionally translucent or substantially transparent, optionally exhibiting one or more selected colors; a reflective element; and an outcoupling element comprising an optically transmissive material having a refractive index equal to or higher than a first refractive index.

[0107] As indicated in the figure, a number of light exit elements 108 may be provided at desired locations of the common multilayer structure 100 , for example on either or both sides of the transmissive element 104 .

[0108] In some embodiments, the spatial distribution and / or other characteristics of the light exit element 108 and / or other optically functional / meaningful elements (e.g., elements 106, 114, 116) may be configured based on a reference object such as the light source 110 or specifically a distance to the reference object.

[0109] For example, if illumination uniformity of the outcoupled light on the exit surface is desired, the efficiency and / or frequency of the light exit elements can be increased (i.e., the mutual distance between adjacent exit elements, the so-called pitch, can be reduced) and the distance to the light source 110 can be increased to compensate for the losses and the generally reduced light reaching areas farther from the light source 110. The uniformity can be simulated first in the design phase using applicable common or proprietary optical simulation tools and later measured on the target area during the prototyping phase.

[0110] One way to determine uniformity is to determine the ratio between the minimum brightness and the maximum brightness over the target area. Naturally, still depending on the materials used, the dimensions, the light sources 110, etc., by positioning the light sources 110 sufficiently densely and potentially adaptively as proposed herein and applying the cladding 106, relatively high uniformity values ​​can be achieved very conveniently, optionally supplemented by clever use of further features such as the light exit element 108, as envisaged above. On the other hand, by adopting the cladding 106, various requirements relating to other aspects of the light sources 110, such as spacing, etc., can be relaxed, which can be particularly beneficial in use scenarios where, for example, the space and / or power consumption of the electronic device containing the light source 110 is to be minimized.

[0111] Item 114 refers to a light absorbing or scattering element (naturally, the same element can be both absorbing and scattering). For example, element 114 can optionally be translucent or substantially opaque with respect to selected wavelengths / frequencies, such as those of visible light and / or those emitted by one or more light sources 110 (if different from visible light). Thus, element 114 can exhibit at least one selected color, optionally provided by a color pigment, color dye, color coating, or color film included in the element.

[0112] In various embodiments, a number of structurally and / or functionally different elements, such as any of elements 106, 108, and 114, can be flexibly positioned so as to be selectively alternated, for example, according to a desired positioning scheme, for example, parallel to and / or lateral to the average or overall propagation direction (substantially horizontal in the illustrated scenario) of light transmitted within the transmissive element 104. This can be done to control the light distribution within the structure 100 and, in particular, within the transmissive element 104 and / or to control the associated light outcoupling, masking, and / or attenuation characteristics.

[0113] As will be readily understood by those skilled in the art, Figure 1 The various general principles that have been explained above, such as the components, their functions, materials, other properties, and their mutual configuration in the structure, without explicit reference to any of the accompanying drawings, may be selectively adopted and are essentially applicable in any embodiment of the present invention. For this reason, the following description in conjunction with the remaining drawings will not unnecessarily repeat the general principles. Similarly, unless explicitly stated to the contrary, additional features disclosed for the first time in conjunction with the description of any of the remaining drawings below may be flexibly adopted in other embodiments that are shown or described only in text.

[0114] Figure 2 Shown in 200 Figure 1A variation of the embodiment of the present invention is provided in which an additional film 103 is provided on the other side of the transmissive element 104 opposite to the substrate film 102. Regarding, for example, the properties, materials, functions, dimensions, and components accommodated of the film 103, what has already been stated regarding the film 102 generally also applies to the film 103. For example, the films 102 and 103 may be substantially identical, generally similar, or substantially different from each other in terms of the materials used, dimensions, functions, and / or components accommodated.

[0115] In certain embodiments, film 103 can have the substrate of many other elements that characterize function and / or can serve as desired function.Can be by special connecting member 112b such as pin, rod, printed material, (filling) hole, circuit etc. film 103 or the element such as conductive trace, optical element or electronic assembly such as light source 110 that are arranged thereto be connected to film 102 or the element thereon.Member 112b can comprise for example conductive material or the optical conductive material that are respectively used to provide electrical connection or optical connection.In certain embodiments, even can set up film 102,103 by the common film that has been bent substantially 180 degree at the edge of structure 200.Thus the edge that limits the center portion of common film can be used for connecting film 102,103 that is limited by the opposite end of common film.

[0116] In various embodiments, the film 103 can cover or contain at least a portion of the cladding 106, which is explicitly shown in the figures. However, as further illustrated, there can be many intermediate elements such as layers, optionally including, for example, an absorbing or scattering layer 103a and / or other absorbing or scattering elements 104.

[0117] Additionally or alternatively, at least one absorbing and / or scattering element 102a , 114 , such as the layer 102a , may be provided to or at least closer to the substrate film 102 , for example as a coating.

[0118] As further visualized in the accompanying drawings, this particular and other embodiments of the multilayer structures generally contemplated herein preferably include one or more light output or exit surfaces. Figure 1-2 In the example of FIG, it is explicitly shown that light exits the structure through both the top and bottom surfaces, but there may even be one or more additional or alternative light exit surfaces or areas, for example at either side of the multilayer structure (in this example, the substantially vertical walls). The exit surfaces may be located on the same side of the structure 200 as the corresponding light source 110 (i.e., the film 102 side) and / or on the opposite side (i.e., potentially the film 103 side) relative to the transmissive element 102. In order to promote and enhance light outcoupling via the selected light exit surfaces, many of the light exit elements 108 described herein may have been positioned adjacent to the transmissive element 104, for example in contact with the transmissive element.

[0119] Figure 3 A further variation of the embodiment of the previous figures is shown at 300. In this example, at least one preferably substantially opaque barrier element 116 has been provided, optionally established by molding a suitable plastic material directly onto the substrate film 102, for example between the film 102 and a potential further film 103. The barrier element(s) 116 may have been configured to define a number of optically substantially non-transmissive support structures, such as at least a portion of the inner and / or outer walls for one or more light channels, with the transmissive element 104 typically establishing the core of the one or more light channels and being separated at least in places from the barrier element(s) 116 by, for example, the cladding 106 being disposed therebetween.

[0120] Figure 4 Still another variation of the embodiment of the previous figures is shown at 400. Here, for example, a preferably substantially optically opaque barrier material of one or more barrier elements 116 has been provided to additionally cover the transmissive element 104 and the cladding 106 from above ("above" in the sense of the orientation of the figures; the skilled person will appreciate that this and other discussed embodiments of the invention can be applied in various fixed or dynamic orientations that may or may not follow the orientation of the multilayer structure indicated in the figures) and from the sides (vertical portions / layers) by molding. Thus, the one or more barrier elements 116 can be configured to substantially embed the transmissive element 104 therein onto the substrate 102. However, the cladding 106 has been substantially disposed between the transmissive element 104 and the one or more barrier elements 116 to prevent, for example, unwanted light from within the transmissive element 104 from leaking into the barrier elements 116.

[0121] Including but not limited to Figure 4 In various embodiments of the multilayer structure shown in , the cladding 106 may establish at least one adjacent, and preferably also physically contacting, potentially conformable layer for the transmissive element 104 in any direction relative to the transmissive element.

[0122] For example, at least a portion of the cladding 106 may be disposed below the 106d element 104, thereby being closer to and potentially conforming to the shape of the substrate film 102, which may further serve as a substrate for the cladding 106 during fabrication.

[0123] Additionally or alternatively, at least a portion of the cladding 106 may be arranged on a side 106e of the element 104 such that it is beside the element 104 and potentially substantially perpendicular to the film 102 and / or parallel to a side surface of the element 104 .

[0124] Additionally or alternatively, at least a portion of the cladding 106 may be disposed on the top 106 f of the element 104 .

[0125] In the scenario shown, the light exit element 108 has been arranged at an opposite distal corner of the transmission element 104 with respect to the light source 110, optionally by only locally omitting cladding material and / or by actually adding specific light exit elements, but the skilled person will appreciate the fact that additional or alternative light exit elements 108 and associated exit surfaces can also be easily arranged elsewhere in the structure 400, with reference to, for example, the dashed-line depicted area 108 b on the same side of the transmission element 104 as the light source 110 and the substrate film 102; in such a scenario, the cladding 106 and / or the barrier element 116 can establish a substantially continuous protective cover or shell structure over the transmission element 104 and the embedded light source 110. A "patched" area in the uppermost layer of the cladding 106 has been shown with dashed lines at 106 b, which indicates the fact that no openings need to be present in the top cladding 106 or the barrier element 116, especially in the latter scenario described above.

[0126] Based on the foregoing it will be clear to the skilled person that by means of different embodiments of the present invention optically very efficient, more or less selectively masked light guiding structures can be integrated with IMSE electronics and similar multilayer constructions.

[0127] In various embodiments, one or more light emitting elements 108 and / or additional elements such as any of the films 102, 103 can be configured to define, in general or locally, a selected graphic pattern, a touch-sensitive area (when, for example, the embedded electronic device 110, 112 includes touch sensing circuitry such as inductive or capacitive touch sensing circuitry), a visual status indicator area (e.g., to selectively illuminate a circular, rectangular, or more complex area, such as by selectively controlling one or more light sources 110, to reflect a selected state of, for example, the overall multi-layer structure, selected components thereof, or, for example, a housing structure / device), a picture, a number, a letter, a text, an alphanumeric code, etc., such that the shape can be illuminated by light emitted by the one or more light sources 110 and coupled out of the structure 100. As will be appreciated by those skilled in the art, the shape can be jointly defined by, for example, appropriate relative positioning of light blocking material and transmissive material.

[0128] Regarding the lighting characteristics of the various embodiments of the multilayer structures contemplated herein, one of the previously mentioned general goals can be to avoid excessive hot spots by providing uniform illumination or a uniform "brightness" distribution toward one or more selected exit surfaces of the environment. The directionality of the light (e.g., whether the light is more collimated or diffuse) can also be determined on a case-by-case basis. For example, diffuse or collimating lenses, microprisms, or microgratings, such as those implemented through surface and / or embedded (cavity) optics such as reliefs, can be provided on the light exit element and / or other remaining features such as the transmissive element or cladding, through which light previously transmitted within the transmissive element 104 reaches or at least approaches the environment.

[0129] In addition to the light projected or emitted therefrom by the multilayer structure, the perceived uniformity of surface illumination can also depend on the uniformity of reflected external light. Thus, in some embodiments, the outer (external) layer of the multilayer structure can be configured, at least partially, such as at selected light exit locations, as a diffuse surface, to reflect incident external light equally in all directions. This diffuse property can be achieved, for example, by increasing the surface roughness.

[0130] Figure 6 The use scenario of the multilayer structure 600 according to an embodiment of the present invention is shown. The multilayer structure can flexibly and selectively incorporate, for example, Figure 1-4 Various features of any one of the solutions.

[0131] In this roughly isometric partial sketch of the structure 600, which is outlined by means of dotted lines, the light exit element 108 defines an elongated, externally perceptible light strip within the overall structure. In other embodiments, the light exit element 108 can naturally define some other shape. The shape defined by the element 108 can have, for example, an indicative, decorative, and / or lighting function. In the event that the element 108 does not extend to the actual surface of the overall structure 600, a surface layer such as the additional film 103 should be provided at least partially with a transmissive material that allows light to pass through it with sufficient transmittance.

[0132] In the particular example of the figure, cladding 106 has been provided on various surfaces of the transmissive element 104, i.e., the core of the light channel. Cladding is present between the transmissive element and the substrate film and on the opposite side of the transmissive element 104, i.e., closer to the depicted exit element 108. Alternatively or additionally, as illustrated using dashed lines, cladding may be present on any of the sidewalls (vertical in the figure) of the transmissive element 104, simply to emphasize the many different options that the present invention offers product designers with respect to achieving more or less selective confinement of light from one or more light sources 110 within the transmissive medium of the element 104 as it travels to selected exit areas on the surface of the element 104 and the multilayer structure in general.

[0133] If the structure 600 is not continuously illuminated by the plurality of light sources 110 when the structure 600 is powered, the emission element 108 can be illuminated at least intermittently, for example, in a pulsed manner. The sources 110 can be controlled or serviced by an applicable control and / or power circuit system 110b, which can be at least partially located within and / or external to the structure 600. For clarity, the circuit system 110b is shown as being external in the figure, but the circuit system can indeed be at least partially internal and located, for example, on the substrate film 102 or the additional film 103.

[0134] The light source 110 may have been positioned, but not necessarily directly below the light exit element 108 to reduce zero path emissions to the environment and thereby help reduce hot spots, but may be positioned, for example, next to 108 on the substrate film 102 and / or potentially on a further film 103, which is the scenario explicitly shown in the figure.

[0135] Item 118 indicates possible connection elements such as electrical lines, one or more connectors, cables, pins, contact pads, one or more wireless connection elements, etc., naturally depending on the specific embodiment and use case of the invention, said connection elements being, for example, in the direction from an external device to the structure 600, but potentially also in the opposite direction for supplying power and / or control or other data signals between the structure 600 and an external structure or device when, for example, control input, confirmation data, sensor data or other data is obtained through the multi-layer structure and deemed worthy of being passed to the external device.

[0136] As depicted, a plurality of light sources 110 may be arranged on a suitable carrier or carriers such as either of films 102 and 103 in a selected configuration such as a row or matrix configuration (row-column arrangement).

[0137] In some embodiments, the very same unitary multilayer structure 600 may naturally contain multiple light channels having, for example, substantially the properties shown, with their cores established, for example, by the transmissive element 104 and separated by the cladding 106 and optionally one or more intermediate barrier elements 116.

[0138] Figure 7 At 700 an embodiment of a multilayer structure according to the present invention is depicted that incorporates a plurality of light channels 702, 704. As will be readily appreciated by the skilled person, the depicted diagram can be applied directly or with some modifications to, for example, the previously discussed Figure 1-4 scenes. The views may be considered to represent, for example, top or bottom views, relative cross-sectional views taken at a selected slice depth starting from a selected surface, such as the top or bottom surface of the structure, or selective perspective views, i.e., in a realistic embodiment, the depicted elements may be located at different heights and span different lengths in a direction extending substantially perpendicularly towards / away from the plane of the drawing, which direction may, for example, correspond to the thickness direction of the implemented structure. However, both the absolute and mutual positioning of the elements shown and the shapes and sizes applied relative to the depicted plane are merely exemplary, but nevertheless represent a viable option. In order to facilitate understanding of the previous figures and Figure 7 The potential relationship and alignment between the representations of Figure 7 Further demonstrated in Figure 3 An "A" symbol is provided on each side and connected by a dotted line.

[0139] As contemplated above, one or more films or substrate films 102, 103 may be included in the structure 700. Either of the films 102, 103 may have a number of light sources 110 disposed thereon.

[0140] exist Figure 7 In the example, the light channels 702, 704, both of which have a generally elongated shape but still partially different from each other, are configured to be essentially parallel and to a certain extent closely positioned, but in other embodiments the number of light channels, their shape, size, absolute or mutual positioning and / or alignment may naturally be different.

[0141] Considering, for example, light channel 702, either light channel 702 or 704 can have a shape with a substantially regular cross-section, with only the distal / outcoupling end being slightly tapered or "rounded." Alternatively, the shape can be more irregular, at least in places, such as varying more or less continuously in cross-section. For example, the shape can be reminiscent of a funnel, with the volume immediately surrounding or adjacent to light source 110 being smaller and then widening toward light exit region / element 108. This spatially continuous or gradually expanding channel shape is generally adopted in the depicted channel 704, and specifically in the upper half of the channel; the initially narrow shape evolves into a wider, more spacious, and larger outcoupling end. However, substantially inverted (i.e., the volume of the light channel generally decreases with increasing distance from the light source of interest), combined (one or more narrower sections between wider or larger sections), or other shapes are also possible.

[0142] As contemplated herein, light channels 702, 704 may generally be defined by a number of elements.

[0143] The transmissive element 104 of the multilayer structure 700 may be a unitary or substantially monolithic piece of optically transmissive material, or a Figure 7 As shown, the element 104 can include multiple transmissive (sub)elements that are at least physically (if not optically) separated from each other, as discussed above. On the other hand, in various embodiments, even a single piece of transmissive material defining the transmissive element 104 can establish multiple light channels 702, 704, thereby retaining at least one connecting portion between the multiple light channels, as indicated at 703 in the figure, as an alternative to utilizing completely separate transmissive (sub)elements. Thus, the transmissive element 104 can contain, for example, a common body portion 703 to which a plurality of optionally, but not necessarily, parallel protrusions defining the light channels are integrally connected. Depending on, for example, the size and relative configuration, such as position and alignment, of the one or more light sources 110 and the element 104, two or more light channels 702, 704 can also be optically connected via the body with respect to light emitted by the one or more light sources 110.

[0144] However, any of the light channels 702, 704 can be associated with multiple light sources 110 rather than just one, but the latter option is shown in the figure for clarity. The sources 110 can be aligned with each other as desired. Two or more sources 110 can be arranged opposite each other or generally positioned on opposing carrier surfaces such as films 102, 103, and / or positioned about a channel or generally in a row, matrix, ring, or other selected configuration.

[0145] Furthermore, in the illustrated scenario, each channel 702, 704 essentially has a dedicated (exclusive) light source 110, but in other scenarios, the light emitted by a single light source 110 may be diffused into several light channels 702, 704, optionally with the aid of embedded diffusion optics such as a number of lenses, reflectors and / or suitable optical microstructures.

[0146] In a preferred embodiment, the transmissive element 104 defines a transmissive core of at least one light channel 702, 704 wherein light generally propagates in an at least selectively defined manner between the light source 110 and a potential exit area / element 108 or other intended destination.

[0147] The cladding 106 can be arranged to abut, surround and cover the transmissive material of the transmissive element 104, for example at its periphery to define a shell and / or wall structure at least in certain locations, i.e., selectively or substantially everywhere, thereby still potentially excluding many selected exit areas or elements 108.

[0148] The cladding material may generally have been provided in one or more layers and orientations. The cladding 106 may be configured to at least partially cover the transmissive material of the transmissive element 104 in only one or a few directions, or the cladding may at least partially cover the element 104 from substantially every direction. Thus, the cladding 106 may include a number of substantially planar or straight portions (e.g., a coating on a planar or shaped film, on a transmissive element, or on a component) and / or rounded (e.g., annular or tubular) or even angular (e.g., rectangular or cubic) portions, which may also generally adapt to the shape of the transmissive element 104 and channels 702, 704.

[0149] Thus, the cladding 106 may establish at least one adjacent and preferably also physically contacting layer to the transmissive element 104 in any direction relative to the transmissive element, such as below the element 104 (e.g., close to or in contact with the substrate film 102), on one side thereof (beside the element 104, e.g., perpendicular to the film 102 and / or parallel to the side surface of the element 104), and / or on top of the element 104. This is previously reviewed Figure 4 Further demonstration was given in .

[0150] The light exit element 108 is or at least defines a light exit region that is preferably free of, for example, the optical cladding 106 or masking that would prevent or reduce light from being outcoupled therethrough. As contemplated elsewhere herein, the exit element 108 may contain a variety of outcoupling enhancement and / or control features, such as optical microstructures, lenses, and the like. Features may be embedded and / or positioned on the surface of the element 108 and, optionally, on the surface of the entire multilayer structure 700.

[0151] The one or more masking features used to optically isolate, for example, at least a portion of the light channels 702, 704 from the environment and / or from each other may include or consist of various elements included in the structure 700. In the illustrated scenario, areas such as the portion of the transmissive element 104 proximate the light source 110 are masked from the environment of the structure 700, while selected exit (outcoupling) areas or elements 108 at the distal end are preferably unmasked so that a sufficiently undamaged optical path is preserved between the transmissive element 104 and a surface of the structure that directly interfaces with the environment, such as the air / atmosphere or an external device to which the structure 700 may be optically connected.

[0152] Many desired masking features may be implemented by the film(s) while at least partially containing a suitable masking material and / or by many other features 114 potentially still housed by or at least connected to the film(s) 102, 103.

[0153] Furthermore, further reference is made to e.g. Figure 4 Shielding can be achieved by a number of blocking elements 116, wherein the blocking elements 116 cover the transmissive element 104 and the cladding 106 from different directions, thereby still advantageously leaving a number of selected areas 108, 108b unoccupied to enable controlled outcoupling of light therethrough. Thus, the one or more blocking elements 116 can generally serve as, for example, an optically insulating filler or wall material between the channels 702, 704, while the one or more blocking elements 116 can also be configured to isolate desired portions, such as the channels 702, 704, from the environment of the structure 700. The one or more blocking elements 116 can be of a selected color or colors. The one or more blocking elements 116 can further provide structural rigidity and / or various additional insulating properties (hermetic sealing, etc.) to the structure 700.

[0154] The material used for masking can be substantially opaque (i.e., non-transmissive) or at least translucent. Thus, for example, with reference to items 102a, 103a discussed previously, the masking material can comprise a colored material or, in particular, a (colored) coating or other layer having optical masking capabilities. Typically, the masking material can be optically reflective, absorbing, and / or scattering.

[0155] In addition to or instead of similar or even joined elements, the masking of the different light channels 702, 704 may rely on mutually different masking elements.

[0156] In the example shown, the light outcoupled at 704 is more collimated than the more diffuse or non-directional light outcoupled at 702 .

[0157] The overall characteristics of the outcoupled light that leaves the structure 700 and is perceived in the environment may be due to a variety of factors that affect the associated optical path starting from the one or more light sources 110 and ending at the surface properties of the structure 700 or at the actual medium or material of the environment itself. For example, the light extraction element 108 discussed herein may play a major role in adjusting the characteristics and, for example, include a number of collimating structures (e.g., microstructures such as collimating gratings or lenses) and / or diffusing structures (e.g., diffusing surface irregularities or lenses).

[0158] Figure 5 A flow chart 500 is included which discloses an embodiment of a method according to the present invention.

[0159] At the beginning of the method for manufacturing a multilayer structure, a startup phase 502 may be performed. During startup 502, necessary tasks such as material, component and tool selection, acquisition, calibration and other configuration activities may be performed. Special attention must be paid to the selection of individual components and materials that function together and are protected from damage during the selected manufacturing and installation process, which is naturally preferably checked in advance based on the manufacturing process specifications and component data sheets or, for example, by investigating and testing the produced prototypes. Thus, the equipment used, such as molding, casting, laminating, (thermo) forming, cutting, drilling and / or printing equipment, may be brought into operation at this stage. One or more molds may be prepared to have the necessary surface forms, etc.

[0160] At 504, at least one optionally flexible and / or elastic substrate film or potentially other substrate element for accommodating an electronic device is obtained. A readily available substrate material element, such as a roll or sheet of plastic film, can be obtained. In some embodiments, the substrate film itself can first be produced internally from one or more desired source materials by molding, extrusion, or other methods. In some embodiments, the substrate film can be manufactured at least partially from a selected source or raw material, optionally plastic, and at least partially co-manufactured with at least one other element, such as a coating, as will be discussed in more detail below. Optionally, the substrate film is treated. As desired, the substrate film can, for example, be coated, cut, and / or provided with openings, notches, depressions, cuts, etc. The initial and / or resulting treated film can have, for example, a rectangular, square, or annular shape. The substrate film can be generally or at least selectively opaque, translucent, or substantially transparent in certain locations with respect to a selected frequency / wavelength of light, such as the emission frequency / wavelength of the light source to be disposed thereon. The substrate film can comprise a thermoplastic material, but as discussed elsewhere herein, a variety of quite different materials are suitable for use in the substrate films and other films contemplated herein.

[0161] At 506, with reference to related additive technologies, a plurality of conductive traces defining, for example, a desired circuit pattern or circuit design and / or contact pads (or other contact areas) for electrically coupling electronic components such as light sources, power (power supply) circuit systems, and / or control circuit systems are preferably provided on the substrate film by one or more printed electronic device technologies. For example, screen printing, inkjet printing, flexographic printing, gravure printing, or offset lithography can be utilized. However, more traditional etching-based methods are also contemplated, provided that, for example, the substrate material used is compatible therewith. Additional actions of cultivating the substrate film can also be performed here, involving, for example, printing or otherwise providing a color layer, graphics, visual indicators, coatings, etc.

[0162] Likewise, in case there are several substrate films or generally films to be included in the target multilayer structure, each film can be processed and provided with the desired processing as well as a number of further elements such as components or conductors.

[0163] At 508, an electronic device comprising at least many light sources, optionally LEDs, is provided on one or more substrate films, the one or more substrate films potentially having one or more other electronic components, such as power circuitry, sensing circuitry and / or control circuitry (e.g., a microcontroller, a processor, a signal processor, a programmable / programmable logic chip, etc.). In practice, for example, many off-the-shelf components such as various SMDs (surface mount devices) can be attached to the selected contact areas, for example, by solder and / or adhesives. Alternatively or additionally, printed electronics technology can be applied to actually directly manufacture at least a portion of a component, such as an OLED, on one or more substrate films. Each included light source can optionally be individually selected, manufactured, or otherwise configured to emit, for example, white light or only selected wavelengths / frequencies (colors), without forgetting potential invisible wavelengths.

[0164] Additionally, at this stage and / or subsequent stages, a number of thermal management elements, such as cooling elements comprising thermally conductive materials, may be provided on one or more membranes and / or elsewhere in the structure, such as embedded and / or on the surface. For example, heat sinks, fins, or heat recovery wells may be provided.

[0165] How electronic devices, such as light sources, are sized, aligned, or positioned relative to one another or to other features of the constructed multilayer structure has been previously discussed. In short, the relative positioning of the various elements should be selected so that desired overall performance goals, such as uniformity and / or optical efficiency of light outcoupled via selected surfaces, are met. However, there may be aesthetic goals, such as those that influence the positioning of the electronic devices and / or masking or blocking elements, such that the electronic devices are not visible from the exterior of the completed multilayer structure.

[0166] In some embodiments, the one or more substrate films and / or one or more other films to be included in the multilayer structure may be formed 520, preferably by thermoforming, such as vacuum or pressure forming, to assume the desired 3D shape (at least partially a substantially non-planar shape). Cold forming may also be applicable. With regard to forming techniques, for example, the aforementioned pressure forming may be applied in order to provide precise, clear details for the substrate; pressure forming is generally preferred when the substrate does not have (through) holes that could enable undesirable flows and the pressure drops generated by the holes. Forming 520 may be performed after the electronic device 508 is provided to avoid associated 3D assemblies. However, alternatively or additionally, 3D forming may have already been performed before stage 508.

[0167] In some embodiments, a number of subassemblies / subsubstrates of an electronic device (e.g., a PCB printed circuit board already supplied with one or more electronic components) can thus be provided at 509 to any one of the substrates and secured, for example, by adhesive and / or solder.

[0168] At 510, at least one thermoplastic layer, preferably but not necessarily, is provided for creating a light-transmitting transmissive element for light emitted by the light source. Specifically, the at least one thermoplastic layer is advantageously produced directly from the material or materials of interest, for example, by molding or casting, onto the substrate film and at least a portion of the electronic devices thereon, such as traces and a number of electronic components. Thus, at least a portion of the electronic devices, such as the light source and / or other elements, provided to the substrate are preferably at least partially embedded within the provided material or materials. Consequently, the optical coupling between the light source and the transmissive element can be made efficient and associated coupling losses reduced.

[0169] In practice, one or both (substrate) films can be used as one or more inserts, for example, in an injection molding process. If desired, selected areas of one or more films, such as edges, can be free of molded plastic. In some embodiments, even both sides of the film can be provided with one or more molded layers. The substrate film can include through-holes or, for example, weakened portions, such as blind holes or cutouts, through which the molded plastic is designed to flow from one side to the other during molding, for example in a molten state.

[0170] The material of the transmissive element used is preferably at least translucent (if not opaque) with respect to the light emitted by the light source. Said material nevertheless exhibits at least one color. The material is associated with a first refractive index.

[0171] At 518, an optical cladding 106, such as one or more layers of one or more selected cladding materials, is established on the substrate film 102, optionally by printing, molding, dipping, and / or spraying adjacent (below, on top, to the side, in between, etc.) the optically transmissive element. As discussed more thoroughly above, the optical cladding can include a material having a lower refractive index than the first refractive index.

[0172] In some embodiments, at least a portion, such as a layer, of cladding 106 can be co-produced with at least one other element, such as substrate film 102, from associated source material(s), rather than providing the cladding on, for example, a fully or predominantly existing substrate film 102. Thus, the source material (e.g., plastic material) can be provided such that it more or less simultaneously creates at least a portion, such as a layer, of cladding 106 and, for example, substrate film 102 as an aggregate, unitary structure, or element. Thus, instead of a more sequential approach, several of the illustrated method items, such as items 504 and 518, can be performed at least partially simultaneously.

[0173] However, item 518 has been purposely shown as an extended entity, potentially connected to the rest of the process in multiple stages. In practice, the cladding may comprise several parts, such as layers, optionally provided in multiple steps, with, for example, one or more other steps, such as providing a transmitting element 518 or a blocking element 512 therebetween.

[0174] For example, as considered above, at least one layer of cladding material may be provided on the substrate before (option "a") or after (option "b") providing, for example, electrical lines / conductors 506 and / or electronic components 508 such as light sources and / or other components on the substrate.

[0175] According to option a, for example, at least one cladding layer can be applied to the substrate such that selected component, conductor and / or other element locations remain free of cladding, possibly due to the use of selective application techniques (e.g. printing by printed electronics technology) or masking, wherein a temporary mask can be pre-set at such locations and removed after the cladding has been provided more or less non-selectively.

[0176] According to option b, for example, at least one cladding layer can be provided on a substrate and a number of components are already positioned on the substrate (circuits, electronic devices and / or one or more other components such as absorbing, scattering, light-exiting or other optical elements) so as to substantially cover these components.

[0177] Options a and b can also be combined flexibly. For example, already mounted components or other elements can be provided with a temporary mask covering which is removed after the substantially non-selective provision of the cladding.

[0178] It should still be remembered that not all embodiments of the present invention require any cladding to be provided exactly between the light source carrying substrate and the transmitting element, since the cladding may be present separately at other locations of the structure, for example on opposite sides and surfaces of the transmitting element, where further films ("further films" 103) may also be present.

[0179] Thus, item 510 may be performed after a certain layer has been provided, quite commonly but not mandatory, for example according to options "a" and / or "b" which have preceded item 510.

[0180] Optional item 512, which involves providing one or more light blocking elements as discussed above, can be performed in association with or subsequent to item 510, for example, by molding. Preferably, items 510 and 512 are performed substantially concurrently using a two-component molding process and / or multiple (at least two) molding fixtures.

[0181] Following item 510 , one or more portions of the cladding structure, such as one or more layers, may be provided 518 , which may be performed before and / or after optional item 512 depending on the spatial configuration and dimensions of the one or more barrier elements produced at 512 .

[0182] For example, Figure 4 As depicted in , if at least one barrier element is to substantially cover at least a portion, if not the entirety, of the transmissive element, any cladding to be provided between said at least a portion and the barrier element is preferably applied over the portion of interest of the transmissive element prior to providing the covering barrier element. Figure 4 While the orientation of the multilayer structure is shown as a directional reference, the cladding layer may thus be arranged to at least partially cover and contact the transmissive element from one or more sides and / or from above.

[0183] However, if we consider, for example, Figure 3 In the case of the scenario of 6, i.e., there will be no barrier element to cover the transmission element in a certain area where a cladding is still required, it is also convenient to provide at least the portion of the cladding after providing the barrier element 512 in another area or areas. The cladding can be provided directly on the transmission element, for example by spraying or printing, or it can be provided first on a film (further film 103) (if any), which is then attached to the remaining structure by lamination.

[0184] However, in the case where two films (the so-called substrate film and the further film) are to be comprised in a multilayer structure and both are to at least selectively receive or be in contact with a cladding structure such that a transmission element and an optional barrier element should be arranged between the two films, both films can first be provided with the intended portion of the cladding and then used as inserts in a molding process during which the transmission element and the optional barrier element are arranged between the two films, in addition to various other elements such as electronic devices and / or optical elements. The option in question can be applied, for example, to Figure 2 and 3 This is particularly beneficial in scenarios where both films contain elements, such as electronic components and / or optical elements, that are to be embedded in the intermediate material of the transmissive (and / or blocking) element, which embedding may be easier during molding (i.e., when the material is generally in a molten / flowing state).

[0185] Typically, when molding is applied, the plastic of interest can be injected through one or more locations, for example, from one or more sides of one or more insert films. Thus, for example, edge injection and / or hole injection (plastic injection between films through one or more holes in one or more films) can be applied. Alternatively, further films, for example, used to create what are referred to herein as "additional films," can then be attached to the aggregate of substrate film and transmissive element, which aggregate optionally also includes a barrier element, by suitable lamination techniques involving, for example, adhesives, pressure, and / or heat-based bonding.

[0186] As contemplated above, the manufactured multilayer structure may further contain a number of other elements, such as light exit elements and / or absorbing or scattering elements. Such elements may be provided to the multilayer structure, and for example, selected receiving elements such as films, blocking elements, or transmissive elements may be provided to the multilayer structure additively (e.g., if not already provided as ready-made elements, then printed, sprayed, or otherwise constructed from source material), subtractively (e.g., the light exit element may be defined by locally removing cladding material from the surface of the transmissive element), or by selectively omitting certain materials from target locations (e.g., cladding material may be selectively introduced initially to define apertures extending therethrough, thereby enabling efficient light outcoupling or generally transmission therethrough). Thus, a skilled person will readily appreciate the fact that such elements may be provided to the multilayer structure being constructed at various stages, for example, in conjunction with items 518, 506, 508, or 514, depending on the nature of the element, its positioning within the structure, and the overall design objectives of the structure.

[0187] When structures are typically constructed in a layered manner, it is often beneficial to arrange the features in the developing multilayer stack by following the same order in which they are to remain in the final structure, but as mentioned above, it is also possible to remove material that has already been arranged to facilitate the inclusion or definition of new features, so following this general rule of thumb is not the only option, nor is it to be followed blindly at all times, and also considers, for example, such molding solutions: in which the material of the transmitting element and optional blocking element can be connected to an existing but initially remote element (positioned as an insert in, for example, a mold half), the remote element such as a film that potentially already accommodates various other elements such as a cladding, other optical features (light exit elements, scattering / absorbing features) and / or electronic devices.

[0188] Item 514 refers to possible post-processing tasks, such as providing further layers and / or other elements in the structure (e.g. optionally provided surface coatings or elements having a protective, fastening, (electrical) connection, tactile and / or aesthetic or indicative function in terms of, for example, a visual pattern, graphic or color) and / or attaching the structure to a containing device. For example, when the structure is in use, one or more outer layers of the structure may face the environment and be subjected to, for example, visual perception by a user. Thus, the surface appearance and, for example, the tactile feel may play a role in the overall suitability of the structure for its intended use, and therefore, the outer layer may be provided with a film or coating which, in addition to potentially having advantageous other properties (e.g. protective or connection functions), is also visually adapted to the context of use in terms of color, graphic, reflectivity or other optical properties and provides a desired surface topology in terms of, for example, roughness.

[0189] At 516 , method execution ends.

[0190] The resulting total thickness of the stacked structure obtained depends largely on the materials used and the associated minimum material thickness to provide the necessary strength, both with regard to manufacturing and subsequent use. These aspects must be considered on a case-by-case basis. For example, the total thickness of the structure may be approximately 1 mm, although significantly thicker or thinner embodiments are also feasible.

[0191] The scope of the invention is determined by the appended claims along with their equivalents. Those skilled in the art will appreciate the fact that the disclosed embodiments are constructed for illustrative purposes only and that other arrangements applying many of the above principles can be easily prepared to best suit each potential usage scenario.

Claims

1. An integrated multi-layer structure comprising a substrate film having a first side and an opposing second side, the substrate film being thermoformed to assume a non-planar three-dimensional shape; an electronic device comprising at least one light source disposed on the first side of the substrate film and a plurality of electrical conductors printed by printed electronics technology at least electrically coupled to the at least one light source, the at least one light source being configured to emit light at least at a selected one or more frequencies or wavelengths, including visible light; an optically transmissive element comprising a thermoplastic material that is optically transmissive with respect to the selected frequency or wavelengths, the optically transmissive thermoplastic material having a first refractive index and being produced by molding from the optically transmissive thermoplastic material onto the first side of the substrate film so as to at least partially embed the at least one light source therein; an optical cladding comprising a material having a refractive index lower than the first refractive index and adjacent to the optically transmissive element disposed on the first side of the substrate film; as well as at least one further film on the optically transmissive element, the at least one further film being on an opposite side of the optically transmissive element relative to the side facing the substrate film, wherein the further film accommodates or covers at least a portion of the optical cladding, wherein the at least one light source, the optically transmissive element and the optical cladding have been configured with respect to one another to transmit light emitted by the light source within the optically transmissive thermoplastic material of the optically transmissive element, at least a portion of the transmitted light undergoing total internal reflection upon being incident on the optical cladding, The integrated multilayer structure includes a plurality of light channels, the optically transmissive cores of the plurality of light channels being established by the optically transmissive element, and the plurality of light channels being separated by one or more walls therebetween, the one or more walls being defined by the optical cladding and the optically non-transmissive blocking element.

2. The structure of claim 1, wherein the material of the optical cladding is optically transparent with respect to a selected frequency or wavelength.

3. The structure of claim 1, wherein the optical cladding further exhibits, at least partially, a non-planar three-dimensional shape.

4. The structure of claim 1 wherein the optical cladding exhibits at least one selected color.

5. A structure according to any preceding claim, wherein the light source is at least partially covered by a cladding material.

6. The structure of claim 1, wherein the optical cladding comprises one or more cladding elements or parts, such as layers, that are not connected to each other.

7. The structure of claim 1 wherein the optical cladding comprises lateral walls relative to a surface of the substrate film.

8. The structure of claim 1 , wherein the optical cladding ( 106 , 106 a , 106 b ) comprises several layers with at least a portion of the optically transmissive element ( 104 ) between the optical cladding layers, wherein two or more layers extend optically parallel to the surface and / or lateral direction of the substrate film, and / or wherein the optical cladding comprises: a layer between the substrate film and the optically transmissive element, the layer being in contact with any one of the substrate film and the optically transmissive element, and a further layer on the opposite side of the optically transmitting element with respect to the substrate film, the further layer being in contact with the optically transmitting element and / or being located between the optically transmitting element and a light blocking element, wherein there is a further cladding layer between the layer and the further layer, the further cladding layer being in contact with the optically transmitting element and connecting the layer and the further layer and / or being oriented transversely to the layer and the further layer.

9. The structure of claim 1 , wherein the substrate film at least partially comprises at least one element selected from the group consisting of: a transmissive material, an opaque material, an optically absorbing material, a light scattering material, a reflective material, a colored film, a colored pigment, a luminescent material, a printed layer, an ink, a graphic pattern.

10. The structure of claim 1 , further comprising an opaque light absorbing or scattering element positioned between the substrate film and the optically transmissive element, wherein the element further exhibits at least one selected color provided by a color pigment, color coating, or color film included in the element.

11. The structure of claim 1 , wherein the additional film at least partially comprises at least one element selected from the group consisting of: a transmissive material, an opaque material, an optically absorbing material, a light scattering material, a reflective material, a colored film, a colored pigment, a luminescent material, a printed layer, an ink, a graphic pattern, an electrical element.

12. The structure according to claim 1, comprising a light exit element arranged adjacent to the optically transmissive element to couple light transmitted within the optically transmissive element and incident on the light exit element out of the optically transmissive element and from the overall structure into an environment of the structure.

13. The structure of claim 12, wherein the light exit element comprises at least one element selected from the group consisting of: a through hole defined in the optical cladding and defined by the material of the optical cladding for enabling the transmitted light incident on the optical cladding to pass therethrough; a grating structure; a prism structure; a cladding-free region or volume between the substrate film and the optically transmissive element into which the transmitted light is incident; an optical mask-free region or volume between the optically transmissive element and the surface of the structure; and a refractive outcoupling element. Diffractive outcoupling element; An outcoupling element comprising an optically transmissive material exhibiting a selected color or colors with respect to a frequency or frequency band; a reflective element; and an outcoupling element comprising an optically transmissive material having a refractive index equal to or higher than the first refractive index.

14. The structure of claim 1 , comprising an opaque optical blocking element adjacent to the optically transmissive element and / or the optical cladding, the optical blocking element defining within the overall structure at least a portion of a light propagation, leakage or crosstalk limiting or masking structure such as an optical structure partition such as an optical channel partition wall and / or a support structure.

15. The structure of claim 14, wherein the barrier element covers or interfaces with the optically transmissive element and / or the optical cladding in any one of the surface and lateral directions of the substrate film.

16. The structure of claim 1, wherein the one or more materials of the substrate film include at least one element selected from the group consisting of: fibrous material, metal, wood, veneer, plywood, bark, natural leather, textile material, formable material.

17. The structure of claim 1, wherein one or more materials of the optically transmissive element, the optical cladding, the optical exit element, or the optical blocking element contained in the structure comprise at least one element selected from the group consisting of: a polymer, an elastic material, an electrically insulating material.

18. The structure according to claim 1 comprises at least one additional electrical or electronic component located on the substrate film, wherein the at least one additional electrical or electronic component comprises at least one element selected from the group consisting of: an integrated circuit, a processing unit, a memory, a communication unit, a microcontroller, a battery, a connector, a diode, a sensor, a capacitive switch, a user interface element, a vibration element, an electrode wireless tag, and an electronic subassembly.

19. A method for producing an integrated multilayer structure, the method comprising: obtaining a substrate film configured to house an electronic device on at least a first side of the substrate film, the substrate film having the first side and a second side; providing an electronic device comprising at least one printable or mountable light source on said first side of said substrate film and a plurality of electrical conductors connected to said at least one light source by printed electronics technology; forming the substrate film into a non-planar target three-dimensional shape; as well as building an optically transmissive element onto the first side of the substrate film by molding or casting and thereby at least partially embedding the at least one light source, the optically transmissive element being built from an optically at least translucent or transparent thermoplastic material having a first refractive index, wherein in the method, an optical cladding is also established adjacent to the optically transmissive element on the first side of the substrate film, the optical cladding comprising a material having a refractive index lower than the first refractive index, wherein the method further comprises providing at least one further film on the optically transmissive element, the at least one further film being on an opposite side of the optically transmissive element relative to the side facing the substrate film, wherein the further film receives or covers at least a portion of the optical cladding, The integrated multilayer structure includes a plurality of light channels, the optically transmissive cores of the plurality of light channels being established by the optically transmissive element, and the plurality of light channels being separated by one or more walls therebetween, the one or more walls being defined by the optical cladding and the optically non-transmissive blocking element.

20. The method of claim 19, wherein the optical cladding is established by molding, dipping and / or spraying.

21. The method of claim 19, wherein at least a portion of the optical cladding is provided using at least one providing technique selected from the group consisting of: selectively disposing on one or more areas on the first side of the substrate film the locations of the one or more selected elements omitted prior to disposing the one or more selected elements on the substrate film, such as the location of at least one element selected from the group consisting of: the at least one light source, an electrical conductor, and a light absorbing or scattering region or element; and Non-selectively arranged on the first side of the substrate film, at least one element further selected from the group consisting of: at least one light source, an electrical conductor, a light emitting element and a light absorbing or scattering element is already accommodated, wherein further, a masking element is first arranged on or next to the at least one element or other selected position on the substrate film, and the masking element is removed after providing the optical cladding.

22. The method according to claim 19, wherein the optical cladding is provided in several layers, at least one layer of said optical cladding is provided in front of at least a portion of said optically transmissive element such that said optically transmissive element at least partially covers said at least one layer; and The at least one further layer of the optical cladding is provided after providing the at least part of the optically transmissive element and is located beside and / or on top of the at least part of the optically transmissive element.

23. The method of claim 19, further building a light blocking element made of an opaque material onto the first side of the substrate film beside and / or on top of at least a portion of the optical cladding by molding adjacent to at least a portion of the optical cladding, the light blocking element being in direct contact with the at least a portion of the optical cladding.

24. The method of claim 19, comprising at least one action selected from the group consisting of: providing the substrate film, the further film or other layer of the multilayer structure with an optical element, the optical element comprising an optically opaque scattering or absorbing element, incorporating removal of the masking element therefrom after providing a cladding material also ending up on a temporary masking element; providing the optical cladding in several steps and layers before providing at least a portion of the optically transmissive element on the substrate film and / or after providing the at least a portion of the optically transmissive element; A light exit element is provided adjacent to or at least optically connected to the optically transmissive element.

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