Optically functional multilayer structures suitable for large area illumination and related methods of manufacture

Abstract

An integrated optically functional multilayer structure (100, 200, 300, 400, 500, 600, 700, 800, 900, 1100, 1300, 1400, 1500) suitable for large area dynamic lighting is suitable for large area dynamic lighting, comprising a flexible, optionally 3D formable and thermoplastic substrate film (102, 102a) arranged with a circuit design (106) comprising at least a number of electrical conductors, the plurality of electric conductors are preferably printed on the substrate film in an additive manner; and a plurality of top-emitting (104a), bottom-mounted light sources (104) disposed on a first side of the substrate film to internally illuminate (104a) at least a portion of the structure for external perception via associated outcoupling regions (112, 112a, 112b, 112c), where for each light source of the plurality, there is provided, optionally at least partially common, an optically transmissive plastic layer (108), which is disposed on a second side of the substrate film, to illuminate (104a) at least a portion of the structure for external perception via associated outcoupling regions (112, 112a, 112b, 112c). A plastic layer, optionally made of a thermoplastic material, disposed on the first side of the substrate film, the plastic layer at least laterally surrounding or adjacent to, optionally also at least partially covering the light source, the substrate film optionally comprising the same material or material layer as the plastic layer, or at least having a similar or lower refractive index; and a reflective sheet design comprising at least one material layer (110) disposed at least between (110b; 110c) on the light source and configured to reflect light emitted by the light source and incident on the reflective layer toward the plastic layer, optionally mainly in a specular reflection manner. Related manufacturing methods are presented.

Description

Technical Field

[0001] The present invention generally relates to functionally integrated structures incorporating various functional features such as electronic, mechanical or optical elements. In particular, but not exclusively, the present invention contemplates providing such structures comprising at least one or more optoelectronic light sources. Prior art

[0002] In the case of different functional sets, for example in the field of electronic components and electronic products, there are various different stacked assemblies and multilayer structures. The motivations behind the integration of functionalities involving, for example, electronic components, mechanical or optical features can be as diverse as the relevant use cases. When the resulting solution ultimately exhibits multilayer properties, it is relatively more common to seek size reduction, weight reduction, cost savings or simply efficient integration of components. In turn, the associated use scenarios can be about product packaging or packaging, visual design of device housings, wearable electronics, personal electronic devices, displays, detectors or sensors, automotive interiors, antennas, tags, automotive electronic components, etc.

[0003] Electronic components such as electronic components, integrated circuits (ICs) and conductors can generally be arranged on substrate elements via a variety of different techniques. For example, off-the-shelf electronic components such as various surface mount devices (SMDs) can be mounted on a substrate surface, which ultimately forms an internal or external interface layer of a multilayer structure. The technology that falls under the term "printed electronics" can be applied to directly produce electronic components and attach them to the relevant substrate. In this context, the term "printing" refers to printing techniques that can produce electronic components / electrical components from printed materials throughout a substantially additive printing process, including but not limited to screen printing, flexographic printing and inkjet printing. The substrate used can be flexible, stretchable and the printed material organic, but this is not always the case.

[0004] Furthermore, the concept of injection molded structural electronics (IMSE) involves building functional devices and their corresponding parts in the form of multilayer structures, thereby encapsulating electronic functionality as seamlessly as possible. The characteristic of IMSE is also that the electronic components are usually manufactured in a real 3D (non-planar) form according to the entire target product, component or usually a designed 3D model. In order to achieve the desired 3D layout of electronic components on a 3D substrate and in the associated final product, the two-dimensional (2D) method of electronic component assembly can still be used to arrange the electronic components on an initial planar substrate such as a film, so that the substrate that has accommodated the electronic components can be formed into the desired three-dimensional (i.e., 3D) shape and, for example, overmolded by a suitable plastic material that covers and embeds the underlying components such as electronic components, thereby protecting and potentially hiding these components from environmental influences. Other layers and components can be naturally added to the construction.

[0005] The optical features and functionality to be provided in the aforementioned integrated structure may include several light sources intended to illuminate, for example, a selected interior of the structure or the surroundings of the structure. The lighting itself may have different motives, such as decorative / aesthetic or functional, such as guiding or instructive motives.

[0006] For example, in some usage scenarios, the environment should be illuminated to increase visibility in shaded or dark conditions, which in turn can enable trouble-free performance of various human activities that usually require relatively high lighting comfort, such as walking, reading or operating a device. Alternatively, lighting can be used to warn or inform different parties, for example, about the status of the structure or an associated host device or a connected remote device, via different warning or indicator lights and, for example, associated graphics. However, lighting can give the structure or its body a desired appearance and visually emphasize specific areas or features thereof via desired colors or brightness. Therefore, lighting can also be used to indicate the user of the structure or its host device, for example, about the location of different functional features, such as buttons, switches, touch-sensitive areas or other user interface (UI) features on the surface of the device, or about the potential actual function of the illuminated features.

[0007] However, in the described and other lighting applications and usage scenarios, various challenges may generally arise.

[0008] For example, from the perspective of the desired optical path and the original illumination target, undesired light bleed or leakage from the structure or between its different internal volumes and regions can easily cause functional and aesthetic problems and transmission losses, as will be readily understood by the skilled person. However, the perceptibility of the light source itself is a potential further problem. In some applications, the light source should preferably remain hidden, or only be exposed faintly or occasionally.

[0009] Additionally, for highly integrated structures, achieving adequate resolution and in many cases also dynamic or adaptive control of the internally transmitted and ultimately outcoupled light, e.g. in terms of illuminated surface area shape, size or location, may at least occasionally become difficult. Among various solutions, controlling or, specifically, improving, for example, the uniformity of light across its entire outcoupling surface (which sometimes also spans a considerable area relative to the overall size of the structure or a selected surface thereof) has previously been found to be cumbersome. The same also applies to more general spatial control of illumination and light outcoupling. For example, this can be a significant issue when a surface contains, for example, icons or symbols that are to be uniformly illuminated to indicate to a viewer outside the structure that the functionality or status of a device associated with the icon or symbol is in effect. Simply utilizing several light sources to more efficiently illuminate a joint target area or feature, such as an icon, can still result in illumination hot spots and additional leakage, while also requiring more power and space, which are often precious. Obtaining the proper mix of brightness or color can also be challenging and require a relatively long distance between the light source and the area or feature to be illuminated by it, particularly in large area lighting applications, which can increase the size of the structure required, or reduce the area that can be illuminated with the proper mixing efficacy.

[0010] Furthermore, some (generally advantageous in many respects) light sources such as high-power LEDs may consume somewhat significant power (easily on the order of about 1 Watt or more) and eventually get so hot that they degrade or break. They may also damage adjacent heat-sensitive components such as plastic substrates.

[0011] Adding multiple potentially complex light directing, input coupling, output coupling, limiting or general processing elements to the structure has its own disadvantages, such as increased space consumption, weight and other design constraints. Maintaining high optical efficiency of the structure with reference to goals such as low leakage, loss and the like can easily further restrict the shape of the structure or included elements to shapes that are otherwise suboptimal for its intended use.

[0012] However, if optical features such as lighting features are to be combined with other features in a structure, the other features may negatively impact the luminous efficacy due to, for example, their shadowing or shading effects, and occasionally the optical features may also hinder or complicate the implementation of other features due to, for example, the space constraints faced.

[0013] In terms of the manufacturing process, in addition to the overall process complexity, the use of various optical features in the structure can also increase the degree of complexity faced due to (in)compatibility of the added features with each other or with the remaining materials and features and related process stages (considering, for example, overmolding), resulting in increased failure rates / reduced yields. For example, if a material associated with a lower melting temperature (e.g., polymethyl methacrylate, PMMA) is used with a higher melting temperature molding material (e.g., polycarbonate, PC), the features printed or otherwise created on the lower melting temperature material may degrade or wash off during molding. Summary of the invention

[0014] It is an object of the present invention to at least alleviate one or more of the disadvantages associated with known solutions in the context of optically functional integrated structures and related manufacturing methods.

[0015] The object is achieved through various embodiments of an integrated functional multilayer structure and related manufacturing methods for providing the multilayer structure.

[0016] According to one embodiment, an integrated optically functional multilayer structure suitable for large-area dynamic lighting comprises:

[0017] a preferably flexible, optionally 3D formable and thermoplastic substrate film, the substrate film being provided with a circuit design comprising at least a number of electrical conductors, preferably additively printed on the substrate film; and

[0018] a plurality of preferably top emitting and bottom mounted light sources disposed on the first side of the substrate film to illuminate at least a portion of the structure from within for external perception via associated outcoupling regions,

[0019] Wherein for each of the plurality of light sources, there is provided, optionally at least partially shared:

[0020] an optically transmissive plastic layer, optionally of thermoplastic material, such as polycarbonate, disposed, such as laminated or produced, on a first side of the substrate film, the plastic layer laterally surrounding or at least adjacent to the light source, optionally also at least partially covering the light source, the substrate film optionally comprising a material or material layer that is the same as the material or material layer of the plastic layer, or at least has a similar or lower refractive index than the material or material layer of the plastic layer; and

[0021] The reflective sheet is designed to include at least one material layer, which is preferably disposed at least on the light source and is configured to reflect the light emitted by the light source and incident on the reflective layer preferably toward the plastic layer, optionally mainly through specular reflection.

[0022] In another embodiment, a method for manufacturing an integrated optically functional multilayer structure comprises:

[0023] obtaining a preferably flexible, optionally 3D formable and thermoplastic substrate film, optionally a multilayer film, provided with a circuit design comprising at least several electrical conductors, such as traces and / or contact pads, preferably additively produced, optionally printed on the substrate film;

[0024] a plurality of preferably top emitting and bottom mounted light source arrangements disposed on a first side of the substrate film; and

[0025] an optically transmissive plastic layer is provided on the first side of the substrate film for each of the light sources which are optionally at least partially shared, the optically transmissive plastic layer at least laterally surrounding or at least adjacent to the light source, optionally also at least partially covering the light source, optionally via lamination or production, such as molding or 3D printing; wherein

[0026] A reflective sheeting design is provided, optionally including printing, coating, lamination or molding, comprising at least one material layer, optionally comprising a stack of material layers and / or conductive and / or metallic material layers, and is configured to reflect light emitted by these light sources and incident on the reflective sheeting design preferably toward the plastic layer, optionally mainly through specular reflection.

[0027] The present solution naturally yields different advantages over a variety of previously applied solutions, depending on its various embodiments.

[0028] For example, the input coupling, transmission and (output) coupling of light can be effectively controlled and the related optical efficiency and various other interesting properties, such as the achieved illumination uniformity, are optimized in the considered optical structure through a clever joint configuration of the included materials and elements (such light sources) with respect to, for example, their mutual positioning, orientation, size and other properties. This solution is also particularly suitable for large area lighting applications and helps to reduce the number of required light sources or keep it low, which has its obvious advantages in terms of saving space, power consumption, structural and manufacturing complexity, weight, etc.

[0029] Reflectors, such as embedded mirror type, can be arranged opposite or adjacent to a light source using, for example, conductive, typically metallic materials or a plurality of layers of different refractive indices to enable efficient transmission and control of light within the structure. However, interfaces capable of total internal reflection (TIR) ​​can additionally be configured to supplement specular reflectors and, for example, be stacked with specular reflectors for even more precise and flexible control of light transmission.

[0030] A "hide until illuminated" effect may also be produced. For example, graphical symbols provided in structures, various components or, for example, conductive traces may be obscured from external visual perception until a light source intended and targeted to illuminate it is activated.

[0031] In terms of manufacturing, in addition to using off-the-shelf components such as films, components or modules, printing and other cost-effective, flexible and universally controllable methods, such as various molding and coating techniques, can also be cleverly applied to manufacture the desired features.

[0032] By appropriate configuration of the light source and, for example, the proposed reflector design, it is also possible to enhance the mixing properties of the light along the outcoupling surface of the transmissive plastic layer and typically the outer surface of the structure and thus reduce the so-called mixing distance required to achieve the desired mixing efficiency.

[0033] Optical elements such as output coupling elements can advantageously be integrally and monolithically formed in other elements such as material layers by locally deforming the associated materials, which provides a very efficient optical solution and saves space, material and weight, in addition to other benefits such as simplifying the structure and potentially also simplifying the manufacturing process. For example, the mirror effect provided by the reflective sheeting design can be locally destroyed to create a light output coupling element from the deformed portion, or, for example, the material at the TIR enabling interface can be similarly treated to locally change the properties of the interface for enhancing scattering and / or interfering TIR.

[0034] For example, from the perspective of light propagation in the transmissive plastic layer, a circuit design including electrical conductors for powering the light source can be cleverly positioned behind the reflective sheet design so that the circuit design does not interfere with light propagation or at least reduces interference, such as diffusion or absorption.

[0035] By utilizing multiple layers or multilayer elements, adhesion between materials can be improved and, for example, wash-off problems can be reduced, such that materials adjacent to a typical molded transmissive layer are selected to better withstand molding and other processes and also firmly attach to each other or the transmissive layer. For example, optionally coextruded multilayer films, such as PC / PMMA films, can be used in a stacked structure above and / or below the transmissive layer, the stacked structure comprising, for example, a PC resin that is then injection molded or otherwise produced on a PC layer of a multilayer film or between two PC layers of a multilayer film. However, similarly, for example, a printed output coupling element can be disposed on a PC surface in a standard and many ways that facilitate PC surface inks. In addition, the use of coextruded multilayer films reduces adhesion problems between different material layers, since the adhesion obtained from the film coextrusion process is excellent. Different coextruded material combinations with even better refractive index differences can be utilized.

[0036] The proposed multilayers may be modular and use a plurality of mutually different and / or similar modules assembled together to provide different features to the aggregated structure. For example, IMSE sheets or unit-type modules, which are preferably shaped (e.g., hexagonal / honeycomb cells), may be utilized so that they can be directly fixed to each other like pieces of a puzzle. Some modules may contain more features or functionalities, more complex functionalities, more difficult to implement functionalities, or several types of functionalities, such as general electronic components and / or optoelectronic components, such as light sources, while some other modules may be simpler and mainly include, for example, passive optical features (transmissive materials, reflective sheets, masks, etc.) or other features that facilitate manufacturing and can be used to scale the size of the structure. For example, the modules may support snap-fit ​​joints or press-fit fixation to easily fix to each other. In addition to modular single structures, several multilayer structures may be joined together, optionally stacked together, to form even larger collections. Thus, modularity may be cleverly arranged at different levels and resolutions.

[0037] Different embodiments of the present invention can be utilized in many aspects and included in different applications, for example, included in electronic components or electrical appliances containing electronic components, including but not limited to computers, tablets, smartphones, other communication devices, wearable devices, AV equipment, optical devices, home appliances, automotive, displays, panels, medical devices, smart fabrics, furniture, works of art, etc.

[0038] Various additional utilities provided by different embodiments of the present invention will become clear to those of ordinary skill based on the following more detailed description.

[0039] The expression "a number" herein may refer to any positive integer starting from one (1).

[0040] Correspondingly, the expression "plurality" may refer to any positive integer starting from two (2).

[0041] The terms “first” and “second” are used herein to distinguish one element from another and do not particularly prioritize or rank them if not explicitly stated otherwise.

[0042] The exemplary embodiments of the invention presented herein are not to be interpreted as limiting the applicability of the scope of the appended claims. The verb "comprise" is used herein as an open-ended limitation, which also does not exclude the presence of unrecited features. Unless explicitly stated otherwise, the features described in the various embodiments and, for example, in the dependent claims, can be freely combined with each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Selected embodiments of the invention are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings.

[0044] Figure 1Various features and aspects of the present invention are described via embodiments of the multi-layer structure according to the present invention.

[0045] Figure 2 Another applicable configuration of the retroreflective sheeting design in different embodiments of the present invention is described.

[0046] Figure 3 Another applicable configuration of the retroreflective sheeting design in different embodiments of the present invention is described.

[0047] Figure 4 Depicts possible placement of holes in the reflector design and potential configurations of other layers in the optical path for light outcoupling from the structure.

[0048] Figure 5 An embodiment is described in which the output coupling element is already arranged on the plastic layer.

[0049] Figure 6 Embodiments of embedded circuit boards for carrying at least one light source and potentially another electronic component and a reflector design including a parabolic reflector surface are described and provided.

[0050] Figure 7 Another potential embodiment is described that includes a parabolic reflector surface and shape.

[0051] Figure 8 Embodiments of lighting systems that include multiple multi-layer structures discussed herein are described.

[0052] Fig. 9 Embodiments are described in which a lighting module is included in the structure, the lighting module comprising at least one light source located on a circuit board, the circuit board potentially further carrying additional electronic or optical components.

[0053] Fig.10 is a flow chart of an embodiment of a method according to the present invention.

[0054] Fig.11 Embodiments of structures including multiple light sources and associated control circuitry are described.

[0055] Fig.12 An embodiment is described that includes bends in the plastic layer.

[0056] Fig.13 An alternative arrangement of material layers of a multi-layer structure is described, wherein the retroreflective sheeting design, such as its material layer, may be at least partially adjacent to the plastic layer.

[0057] Fig.14 Describes the different options and configurations for light output coupling.

[0058] Fig.15Further embodiments of multi-layer structures with additional functionality such as touch or gesture sensing are described. DETAILED DESCRIPTION

[0059] Figure 1 An embodiment of a multilayer structure according to the present invention is generally illustrated at 100 via a cross-sectional sketch.

[0060] The multilayer structure comprises at least one substrate film 102, which preferably has a flexible and 3D formable (3D shaped) material, such as a thermoformable (plastic) material. As is understood by a person skilled in the art, instead of a single, optionally monolithic film 102, there may be a film 102a of a multilayer and / or multi-segment construction type, for example with mutually different layers at least in some places, also including a carrier layer for electronic components. Such a multilayer film 102a can be manufactured via coextrusion (for example as part of an embodiment of the method considered below).

[0061] Item 108 refers to at least one, preferably also thermoplastic and at least optically transmissive layer, which is preferably provided via molding on the substrate film 102. Optionally, the layer 108 may be produced essentially between the substrate film 102 and a possible further element or generally a material layer, such as at least one other layer or film different from or similar to the film 102. Alternatively, the item 108 may refer to a plurality of stacked, preferably still thermoplastic and / or integrated layers, which may optionally be produced via multiple injection molding. The layer 108 should be able to transmit light at least taking into account selected wavelengths, such as substantially all or selected wavelengths of visible light or generally at least part of the wavelengths emitted by the included light source, which generally but not necessarily include visible light wavelengths.

[0062] Layer 108 includes a first side and associated first surface 108a, which, depending on the application, may be oriented toward the use environment of the structure and, for example, a user 113 of the structure located in such an environment. However, by way of example, layer 108 includes an opposite second side and associated second surface 108b, which substantially faces at least one instance of film 102 and potentially a host device or structure. However, in alternative embodiments, surface 108b may be the surface that substantially faces the use environment and, for example, a user therein, instead of or in addition to surface 108a.

[0063] Since layer 108 should actually transmit or guide light, it should include a material that is optically at least translucent, optionally substantially transparent, wherein the optical transmittance of the overall thermoplastic layer may preferably be at least 50% in some use scenarios, but the required transmittance may actually vary substantially between all possible use scenarios. In some embodiments, at least about 80% or 90% transmittance may be preferred for maximizing light output from the structure and low losses, while in some other scenarios, lower values ​​may be entirely sufficient (if not disadvantageous) if, for example, problems related to light leakage are to be minimized. Taking into account the wavelengths of interest, which typically include visible light wavelengths as described above, the transmittance can be defined or measured in a selected direction (e.g., the main direction of light propagation) and / or in a direction lateral to the surface of the substrate film 102 (i.e., the thickness direction).

[0064] For example, in some embodiments, suitable translucency or light attenuation of layer 108 can be achieved by employing scattering elements, such as particles in the material used. As the number of scattering elements increases, scattering / diffusion and half-power angle as a possible measurable indicator also increase, while light transmission through the layer will generally decrease. Correspondingly, increasing layer thickness generally increases scattering / diffusion properties, such as half-power angle, and decreases transmission.

[0065] In terms of applicable materials, layer 108 may generally include, for example, at least one material selected from the group consisting of: polymers, organic materials, biomaterials, composite materials, thermoplastic materials, thermosetting materials, elastic resins, PC, PMMA, ABS, PET, copolyesters, copolyester resins, nylon (PA, polyamide), polypropylene (PP), thermoplastic polyurethane (TPU), polystyrene (PS or GPPS, general-purpose polystyrene), thermoplastic silicone vulcanizate (TPSiV) and MS resin.

[0066] The substrate film 102 may optionally include the same material or material layer as the material or material layer of the layer 108, or at least have a similar or lower refractive index than the material or material layer of the layer 108. Therefore, the resulting interfaces 102, 108 can be made optically transparent, or achieve a total internal reflection (TIR) ​​type function respectively, for light to reach the interface from within the layer 108.

[0067] In some embodiments, a tinted or more intensely tinted resin as a material for layer 108 may provide a viable option to limit unwanted light leakage inside and outside the structure 100, thereby enclosing elements or general distances, and hiding internal components such as light sources 104 or other circuit systems from external perception. Thus, an initially optically substantially clear substrate material (such as PC or other plastic resin) may thus be doped with a tinted masterbatch. In many use scenarios, where the total thickness of the structure 100 should be only, for example, a few millimeters or a centimeter, and therefore the thermoplastic layer 108 should be even thinner, using a plastic resin layer of about 2 mm to 4 mm (such as 3 mm) thick may provide very satisfactory results, providing the selected masterbatch (e.g., white or desired selective wavelength resin, optionally also an IR resin, such as can be used for example for infrared (IR) remote control applications) in the desired concentration (e.g., a dilution ratio of about 1%) for building up the layer 108. Typically, in many embodiments in the context of the present invention, the feasible dilution (dosing or doping) ratio is actually about 5%, 4%, 3%, 2%, 1% or less. Suitable industrial grade masterbatches for this purpose are available, for example, from Lifocolor TM For light source 104 or other features included in structure 100 , a so-called “hidden until lit” effect may be achieved, for example, by incorporating a translucent (eg, in a selected color) masterbatch into the injection molded base resin that makes up layer 108 .

[0068] Item 124 refers to an outer coating that at least partially covers the light emitting portion of the light source, the outer coating comprising an optically transmissive material that optionally has a higher refractive index than the plastic layer.

[0069] The outer coating 124 may include an optionally selected encapsulant, globe top or other conformal coating such as Illumabond for, for example, light shaping or other processing, protection and / or securing purposes. TM or Triggerbond TM . The substance used may be dispensed on top of selected circuitry such as light source 104 or other electronic components included in the structure. For example, the substance may be substantially clear (transparent). Alternatively, it may be colored and / or translucent. In some embodiments, specific optical functions or features such as lenses may be provided by the package. For example, the lens may be diffuse, Fresnel, or, for example, collimating. Additionally or alternatively, prefabricated lenses or general optical components may also be included in the structure, either on the surface or embedded.

[0070] The substrate film 102 and / or another film or general material layer included in the multilayer structure may include at least one material selected from the group consisting of: polymers, thermoplastic materials, electrically insulating materials, polymethyl methacrylate (PMMA), polycarbonate (PC), flame retardant (FR) PC films, FR700 type PC, copolyesters, copolyester resins, polyimides, copolymers of methyl methacrylate and styrene (MS resins), glass, polyethylene terephthalate (PET), carbon fibers, organic materials, biomaterials, leather, wood, textiles, fabrics, metals, organic natural materials, solid wood, thin boards, plywood, stem bark, bark, birch bark, cork, natural leather, natural textile or fabric materials, naturally grown materials, cotton, wool, linen, silk, and any combination of the above.

[0071] Depending on the embodiment in question, the substrate film 102 and / or another film or layer that may be included in the structure may include or have a material that is optically substantially transparent or at least translucent, taking into account a wavelength of interest, such as visible light, with a relevant optical transmittance of, for example, about 80%, 90%, 95% or more. This may be the case in particular when the substrate film 102 is configured in the structure 100 to effectively transmit or transfer light emitted by the light source 104. However, in some embodiments, the substrate film 102 used may be substantially opaque, black and / or otherwise dark in color to block incident light from passing through it (masking function).

[0072] The thickness of film 102 and optionally another film or layer included in structure 100 may vary depending on the embodiment; for example, it may be only tens or hundreds of millimeters, or substantially thick, such as on the order of one or a few millimeters.

[0073] The thickness of layer 108 may also be selected on a case-by-case basis, but a thickness of several millimeters, such as about 3 to 5 millimeters, may be applied. In some embodiments, a thickness of only about two millimeters or less (potentially only, for example, tenths of a millimeter) may be sufficient, if not optimal, while in some other embodiments, the thickness may also be quite large, such as about 1 cm or more, at least in some places. The thickness may actually vary locally. For example, in addition to accommodating various components such as electronic or optical components, layer 108 may optionally include recesses or internal cavities for guiding light, processing and / or thermal management purposes.

[0074] The film 102, layer 108 and other layers (such as films, coatings, etc.) of the structure can be substantially planar (width and length are greater than thickness, for example, different in magnitude from thickness). This generally also applies to the overall structure illustrated in the figures, although other non-planar shapes are also entirely feasible.

[0075] Item 104 refers to a light source, preferably of the optoelectronic type. Light source 104 may be or include a semiconductor, packaged semiconductor, chip-on-board package semiconductor, bare chip, electroluminescent and / or printed light source, preferably a light emitting diode (LED) or an organic LED (OLED). Light source 104 may be top-emitting and bottom-mounted, or side-emitting. However, depending on the characteristics of each specific use case, multiple side emitters or bottom emitters may be utilized.

[0076] Still in terms of packaging, the light source 104 may optionally be of flip chip type. In some embodiments, the light source may contain multiple (two, three, four or more) light emitting units such as LEDs packaged or at least grouped together. For example, a multi-color or specifically RGB LED of several LED emitters may be provided in a single package.

[0077] The light source 104 is arranged, such as produced (optionally with reference to, for example, OLED printing), or in the case of at least partially off-the-shelf components, mounted on the substrate film 102, preferably mounted on the first side 102f and its associated surface, which faces the transmissive layer 108, rather than the surface opposite the second side 102s and the film 102. However, additional body layers, such as films, may be included in the structure for accommodating other components such as light sources or other electronic components. For mounting, for example, an adhesive (conductive or non-conductive) may generally be applied.

[0078] During overmolding or otherwise preparing the layer 108 thereon, the light source 104 may be at least partially embedded in the material of the layer 108 .

[0079] The layer 108 may include one or more light outcoupling regions 112 on either side of the layer 108, such as the first side 108a or the second side 108b, via which light originally emitted by the light source 104, input coupled into the layer 108, and propagating within the layer, will be outcoupled to surrounding layers and / or the environment. The light source 104 may be positioned as desired with regard to the corresponding outcoupling regions 112. The source 104 may be positioned close to the region 112, such that an associated direct optical path may be obtained even without reflection from the emitting surface of the source 104. Alternatively, and perhaps more commonly, source 104 is located beside and further away from an associated outcoupling region (e.g., outside of LOS, line of sight to the region or an external environment adjacent to the region) for a variety of reasons, which may include, for example, better hiding or shielding source 104 from external perception, or facilitating improved mixing by causing light emitted by source 104 to propagate (primarily or also via reflection) a longer distance and time within layer 108 and at adjacent layer or material interfaces to enhance illumination uniformity (e.g., brightness and / or color) across region 112. For clarity, Figure 1 Only a single light source 104 is shown, and in many embodiments one light source 104 may be sufficient, if not advantageous, but as will be readily appreciated by one of ordinary skill, there are countless embodiments that may benefit from including several light sources 114 on the same or different substrates (and utilizing shared or separate transmissive layers 108 and / or reflective sheeting designs 110) in the structure, or having at least partially joined or separate output coupling regions 112 associated therewith, affecting the positioning and orientation of the light sources 104, for example in the field of large area illumination.

[0080] Item 106 refers to a circuit design in the form of one or more electrically, optionally additively produced (such as screen printed or otherwise printed) conductors (such as traces, electrodes and / or contact pads), which conductors may optionally further act as thermal conductors. The conductors may be used, for example, between elements of the structure 100 and / or with external elements for power and data transfer purposes. Among other uses, the circuit design 106 may also provide control signals and / or power to the light source 104 from the controller and the power supply circuit, respectively. The circuit design 106 may be connected to an external device via, for example, an outer surface or edge of the structure 100 containing wiring or connectors. Additionally or alternatively, wireless connections may be applied based on, for example, electromagnetic or particularly inductive coupling, as well as other options. The circuit design 106 may be arranged on or in the substrate film 102 and / or other main (load-bearing) elements (such as material layers of the overall multilayer structure). In the structure, for example, on different layers or bodies thereof, there may be several local or partial circuit designs 106 that may be selectively connected together, at least operatively (if not physically), and establish a larger circuit design that spans several elements (such as the layers of the structure). Some elements, such as conductors (e.g., traces), may be physically located according to distribution or shared between two or more layers of the structure (e.g., a first portion resides on / in one layer and a second portion resides on / in another layer). Thus, such elements may be considered as several local circuit designs (e.g., located on different layers) or as part of a larger circuit design.

[0081] The light source 104 may be emissive, as shown by the dashed lines 104a (top exit), 104b (side exit) extending from the source 104 into the transmissive layer 108 .

[0082] Item 110 and sub-items 110a, 110b, 110c (see Figure 2 ) refers to a retroreflective sheeting design, which may also be a single-component or multi-component (multi-part) construction. Two or more components of a multi-component construction solution need not be physically directly connected, as they may, for example, reside on opposite sides 108a, 108b of layer 108, or otherwise be separated by a distance. However, any of the components or parts may include one or more material layers, such as stacked, as its constituent elements.

[0083] Thus, the retroreflective sheeting design 110 includes at least one material layer. The retroreflective sheeting design 110 is configured to reflect, preferably primarily specularly reflect, light that is initially emitted by the at least one light source 104 and that is incident on the retroreflective sheeting design 110 .

[0084] One or more portions of the reflector design 110 or the entire design 100 may be located on a side of the plastic layer that is identical to (see reflector / reflector portion 110a for illustration), opposite to (see reflector / reflector portion 110b for illustration) and / or transverse to (particularly see reflector / reflector portion 110c for illustration) the first side 102f of the substrate film 102 that faces the light source 104.

[0085] In some embodiments, as depicted at 150, the context ( Figure 1 ), at least a portion of the conductors 106a that establish the circuit design 106 may be configured to be located outside the light-transmissive plastic layer 108, the reflective sheeting design 110, and potentially another intermediate layer (such as layer 114), and thus, for example, on a side of the reflective sheeting design 110 that faces away from the light-transmissive (optically transmissive) plastic layer 108, and optionally on a surface, rather than on a side that faces the light-transmissive plastic layer 108. In general, at least a portion of the conductors may thus be kept away from the volume spanning the layer 108 and possible intermediate spaces to the reflective sheeting design 110, even if the conductors 106a are configured to transmit, for example, data or energy to / from an electronic component, such as a light source 104, that optionally resides at least substantially or partially within the volume.

[0086] Likewise, at least a portion of the substrate film 102 itself may be positioned on a side of at least a portion of the retroreflective sheeting design 110e that is opposite the side that actually faces and potentially is directly attached to and in contact with the optically transmissive layer 108. The stacking sequence of the retroreflective sheeting design 110e and the substrate film 102 may thus be at least partially aligned with, for example, Figure 1 104. The stacking order is reversed from the main illustration provided in FIG. 106. For example, one or more conductors of design 106 may be disposed on substrate film 102, parallel to its surface (e.g., adjacent to or below an electronic component such as light source 104), which is also depicted in the sketch. Instead of directly producing layer 108 via molding on substrate film 102 (and potentially on one or more conductors of circuit design 106 and / or light source 104 already disposed on film 102), for example, layer 108 may be pre-fabricated before being attached to substrate film 102, optionally with features 103, such as holes for accommodating at least a portion of light source and / or reflector design 110e, which is indicated by two arrow symbols in the figure. Suitable lamination techniques based on, for example, adhesives, heat and / or pressure may be used for this purpose.

[0087] Thus, the optical efficiency of the arrangement and indirectly also the electrical efficiency can be improved, since the conductor, at least partially (if not mostly or substantially completely) positioned at a distance from the transmissive layer 108, will not interfere, or at least interfere less, with the optical path of light emitted by the light source 104, propagating in the transmissive layer 108 and at least occasionally reaching and reflecting from the reflective sheeting design 110. Otherwise, the conductor may cause excessive undesirable phenomena to the incident light, including, for example, diffusion and absorption. However, in certain embodiments, the influence of the conductor on the incident light may additionally or alternatively be used for useful purposes, such as optical effects (diffusion, attenuation or shadowing, etc.).

[0088] In preferred embodiments, the sheeting design 110, or at least a portion thereof, is generally configured to reflect incident light that would have previously propagated within the (transmissive) layer 108, at least generally toward or away from the layer 108, to prevent, for example, undesired light outcoupling or light leakage from the structure 100. In some embodiments, the sheeting design 110 may include at least a portion that is in turn configured to direct incident light to an alternative direction, such as outside of the layer 108 or the entire structure 100.

[0089] Additionally, the sheeting design 110 can be configured on or in the layer 108 to reflect and direct light emitted by the light source 104 and incident on the sheeting design 110 toward the outcoupling regions 112, 112a, 112b, 112c. In some embodiments, which will also be discussed below, the sheeting design 110 can be configured to direct the incident light more toward the surface normal of the layer 108 for outcoupling the light from at least the layer 108 or the entire structure.

[0090] In fact, referring to e.g. Figure 2 and Figure 3 As shown in the sketch in FIG. 1 , for example, the reflector design 110 can be configured in conjunction with at least light input coupled from the light source 104.

[0091] The retroreflective sheeting design 110 or at least a portion thereof may be located 110a, 110b, 110c in a direct light path from the light source 104. In addition, the retroreflective sheeting design 110 may be located or include a portion 110b located on and / or opposite the light source 104 (e.g., on an opposite side 108a of the layer 108 relative to the light source 104), beside and / or below the light source 104, such that the design 110 receives and reflects at least a portion of the light emitted by the light source 104.

[0092] As shown in the figure, only as an example, Figure 3At 300 in FIG. 1 , the reflector design or a portion 110 b thereof can be configured to reflect light input coupled into layer 108 from light source 104 and incident on the reflector design 110 to be more aligned with a side of layer 108 that is substantially transverse to the surface normal of layer 108 .

[0093] Typically, a portion of the retroreflective sheeting design 110, 110a, 110b, 110c may be at least partially embedded in the layer 108 and / or on its surface 108a, 108b.

[0094] At the same time, as shown by the example, Figure 2 At 200 in FIG. 1 , the light source 104 can be located between at least a portion of the reflector design 110c, which is preferably aligned substantially perpendicular to the light outcoupling region, and the light outcoupling region 112. The light source 104 can then be aligned according to its primary emission direction to be at least partially directed toward the reflector design 110c. For example, a light source, such as a side-emitting LED or other light source, can be aligned to point, for example, about 180 degrees (shortest path) away from the outcoupling region 112, 112a, 112b, 112c.

[0095] Thus, the distance between a light source 104, or a light source 104 in a typical scenario where several light sources are used, and the associated outcoupling regions 112, 112a, 112b, 112c can be kept short and reduced relative to more conventional solutions, while the corresponding optical path defined by the path actually taken by the light emitted by the light source 104 before being outcoupled 112 can be increased by approximately twice the distance D shown in the figure (i.e., the distance between the reflector design 110c and each of the considered light sources 104). This results in a smaller applicable multilayer structure and / or larger outcoupling regions 112, 112a, 112b, 112c with suitable light mixing characteristics, depending on the preference setting for the application as understood by the skilled person.

[0096] At selected, optionally substantially all visible light wavelengths, such as at least a portion of the wavelengths emitted by source 104, sheeting design 110 preferably has a reflectance of at least locally about 75%, preferably at least about 90%, and most preferably at least about 95%.

[0097] To achieve, for example, sufficient reflectivity, the reflective sheeting design 110 or some other optical functional elements included in the structure preferably at least partially include at least one element selected from the group consisting of:

[0098] - conductive materials such as aluminum, silver, gold, zinc, copper or beryllium;

[0099] - a metal, optionally metal particles, further optionally disposed on or in the substrate film or another film or another film or layer comprised in the structure;

[0100] - a plurality of stacked, superimposed material layers of at least two mutually different refractive indices, optionally defining a Bragg mirror; - a thin film coating, optionally a physical vapor deposition (PVD) protrusion; and

[0101] - (Reflective) Preferably printable ink or coating.

[0102] Thus, by using conductive materials such as metals in one or more layers of the retroreflective sheeting design 110, the so-called skin depth of the retroreflective sheeting design 110 and the entire underlying structure can be kept small and thus reflective efficiency high. The conductive materials and metals can be provided, for example, in a film, coating, ink or extrusion (e.g., metal particles in a host material such as plastic) process. In principle, any practical metallization process can be applied to provide the metal.

[0103] Alternatively or additionally, multiple stacked layers (potentially even tens or hundreds of layers) may be applied to establish a common effective, preferably integral reflective structure, such as a Bragg mirror. In such structures, layers of different refractive indices may alternate in sequence. For example, two materials of different refractive indices may be configured to alternate in a multilayer reflective sheeting stack that constitutes at least a portion of the reflective sheeting design 110. At each interface between two material layers, Fresnel reflections are advantageously produced. When the optical path length difference between successive layers is half of a wavelength (i.e., each layer is a quarter of a wavelength thick), the reflections constructively interfere (zero / 360 degree phase shift between reflections). For example, plastic polymer materials may be used in multilayer reflective sheeting stacks, such as PMMA and PC or PS. In some embodiments, the stacked integral multilayer element may also include a substrate film 102 and / or other films or conventional layers or features, such as items 114, 116, which will be discussed in more detail below.

[0104] The stack included in the retroreflective sheeting design 110 can be up to an optional ready-made multilayer film. Alternatively, several optional stacked material layers of the retroreflective sheeting design 110 can be produced on a substrate such as substrate film 102 via a selected coating technique (e.g., PVD (physical vapor deposition) or electroplating on plastic). Alternatively or additionally, for example, a (multiple) coextrusion process can be applied.

[0105] Item 114 simply refers to at least one further, optionally additively produced, e.g., material layer via printing, optionally stacked and further optionally in contact with retroreflective sheeting design 110. At least one further material layer 114 preferably has a lower refractive index than layer 108. For example, when layer 108 has PC, layer 114 may comprise PMMA.

[0106] The at least one additional material layer 114 and layer 108 can be optically connected, and optionally also physically adjacent, to redirect at least a portion of the light emitted by the light source, propagating within the plastic layer 108 and incident on the at least one additional material layer 114 back to the plastic layer via total internal reflection (TIR) ​​at their interface. Typically, and for example in the case where the retroreflective sheeting design 110 is stacked with and located, for example, behind the interface of the layers 108, 114 on the optical path, the retroreflective sheeting design 110 can effectively write with the interface and reflect the remaining light that, for example, passes through the interface at an angle below the relevant critical angle and is therefore incident on the retroreflective sheeting design 110 behind.

[0107] At least one layer or other portion of the retroreflective sheeting design 110 , the layer of the at least one additional material layer 114 , and the layer 108 may therefore at least partially overlap in terms of their material such that the material of the layer of the at least one additional material layer 114 is stacked between the material of the retroreflective sheeting design 110 and the layer 108 .

[0108] Typically, at least a portion of the retroreflective sheeting design 110, 110a, 110b, 110c and the at least one additional material layer 114 may reside on the same, opposite, or both / several sides 108a, 108b of the layer 108 relative to each other.

[0109] The at least one additional material layer 114 may optionally include or consist of, for example, an optically clear adhesive (OCA) or a primer.

[0110] In general, light propagation in the structure can be effectively controlled technically and cost-effectively using patterned selective low (lower) index materials, such as in layer 114 or elsewhere. For example, selectively generating guided light and guided light enhancement, such as reflective (boundary) structures, via a large structure with one or more light sources 104 can prove advantageous. Guided light structures such as items 108, 110, 114, 116 can be configured to have different optical properties, such as in sections, and, for example, length or generally size.

[0111] In some embodiments, an integrated multi-layer construction, such as multi-layer film 102a, may be included in structure 100 as a pre-fabricated or in-situ manufactured element.

[0112] The multilayer film 102a may include multiple (e.g., two) stacked and attached, optionally co-extruded layers, one of which may be or establish a substrate film 102 or similar layer for carrying the light source 104 and the circuit design 106 and potentially additional electronic components or other components, and at least one other layer may be, for example, at least one layer of the item 114 and / or the reflective sheeting design 110, 110a (which itself may be a multilayer material stack as discussed above), as well as other options.

[0113] In some embodiments, an intermediate layer 116 may be disposed on the first side 108a of the layer 108, such as between the layer 108 and the at least one additional material layer 114 (if present), and / or between the layer 108 and the retroreflective sheeting design 110, 110b.

[0114] The intermediate layer 116, embodied as a film, for example, may also serve as a substrate (surface) for various components such as electronic components including light sources. The intermediate layer 116 may include an optically transmissive material that is optionally the same as the material of the layer 108, or at least has a similar refractive index thereto. The previous considerations provided herein regarding the substrate film 102 may also be generally applicable to the intermediate layer 116, as understood by a person of ordinary skill.

[0115] The intermediate layer 116 and the at least one additional material layer 114 and / or at least one layer of the retroreflective sheeting design 110, 110b may further be components of a multilayer construction such as a multilayer film 116a, further optionally a coextruded multilayer film.

[0116] Items 120, 122 refer to one or more elements such as a material layer of either of the outer surfaces of the structure, optionally located at or at least close to (preferably within one or two material layers) on either or both sides 108a, 108b of layer 108. They 120, 122 may comprise films, coatings, prints, plastic materials, natural materials (leather, etc., as listed above in connection with suitable substrate films / film materials, for example). Depending on the embodiment, items 120, 122 may possess other features (e.g. electronic components) or layers, and thus also be considered substrates. Preferably, items 120, 122 are at least translucent in places, including (through) holes, optionally filled (with at least translucent material), or cover only limited areas, to enable light to be outcoupled from the structure. For example, any of items 120, 122 may be provided using different lamination, printing, coating, molding or extrusion methods.

[0117] Item 118 refers to one or more output coupling elements that the structure may, for example, be initially separate from or integrally (if not monolithically) comprised of any of the remaining elements such as the sheeting design 110 or various (other) material layers.

[0118] For example, the sheeting design 110, such as a layer or other portion thereof, or another element or specifically a layer of a structure having light emitted by the source 104 incident thereon, may carry, be or define a locally treated, preferably mechanically, chemically or electrically treated, optionally deformed, such as stretched, portion, such as a material stack portion (locally two or more layers, optionally all layers of the stack deformed) or a material layer portion, to change the reflective properties for light redirection and output coupling (e.g., change means reduced reflection), respectively, optionally through the layer 108 or more directly not (no longer) through the layer 108. As a practical operating example, such an output coupling element 118 may be provided to the sheeting design 110 (provided to one or more associated material layers) on one side (e.g. side 108b) of the layer 108, such that at least a portion of the light incident on the element 118 is output coupled via the surface 108a of the layer 108 or via the bottom (as oriented in the figure) surface of the structure after having passed through the layer 108, potentially no longer entering the layer 108.

[0119] As hinted above, in lieu of or in addition to the reflector design 110, other elements of the structure, such as layer 108, may locally carry or define, for example, surface features or a surface pattern that constitute at least a portion of an output coupling element 118, optionally including roughened or otherwise deformed regions, for output coupling light incident thereon internally.

[0120] For example, any of the elements 118 may be scattering / diffusing or collimating.

[0121] exist Figure 5 In the cross-sectional sketch of , at 500, a plurality of outcoupling elements 118 are illustrated, comprising several, preferably printed, optionally scattering elements, having spatially varying incident densities and / or sizes, preferably at least thickness, on the layer 108 with respect to one another.

[0122] Thus, in the described and other use scenarios and embodiments, the incident density, thickness and / or one or more other dimensions of the output coupling elements 118 can be configured to increase with distance from the light source 104 to respectively enhance the output coupling efficiency with distance (e.g., at least relatively compared to the output coupling efficiency of closer elements 118), one or more of which optionally include fluorescent, phosphorescent, thermochromic, or photochromic materials.

[0123] For completeness and to facilitate understanding of the different configurations that embodiments of the present invention may employ in each application, Fig.13An alternative arrangement of material layers included in the structure is illustrated at 1300. In particular, at least a portion of the retroreflective sheeting design 110, such as one or more layers thereof (if not as a unitary design), may be at least partially adjacent to layer 108 and / or stacked between layer 108 and, for example, film 102, while, for example, Figure 1 1, the retroreflective sheeting design 110 is shown behind the film 102 from the perspective of the layer 108, ie, closer to or at the exterior or outer surface of the structure.

[0124] However, in some embodiments, at least a portion of the reflective sheeting design 110 may be positioned adjacent to the substrate film 102 so that light can be input coupled from the light source 104 into the substrate film 102 and then propagate within the substrate film 102 via reflection (mirrors, TIR, etc.), depending on the adjacent element or, in particular, layer, until incident on the output coupling region 112 or element 118, which then allows the light to travel to the exterior of the substrate film 102 and optionally pass through the plastic layer 108 into another layer and / or the environment. For example, in such a scenario, the output coupling region 112 or element 118 under consideration may also include or consist of a deformed substrate or generally a material portion, a coating or a printed portion.

[0125] Figure 4 An embodiment is illustrated at 400 via a cross-sectional sketch in which a number of holes 410 have been configured in the reflector design 110 to enable or facilitate light to be output coupled through the reflector design 110 and optionally exit from the overall structure, again naturally depending on the optical transmission characteristics of subsequent upper (in the figure) layers and elements in the optical path. Thus, the figure also depicts a potential configuration of several other layers in the optical path for light to be output coupled from the structure, wherein one or more of the other layers or elements 412, 414, 416 may also be provided with holes at least in certain places, which in turn may be configured to be stacked or laterally aligned with holes in other layers (such as holes 410 in the reflector design 110). As shown, for illustrative purposes, on the left, holes 410 pass through all layers in the layer 108, while on the right, holes 410 only appear in items 110, 412.

[0126] One or more holes 410 in any of the items 110, 412, 414, 416 may be free of material (and thus may contain, for example, air during the manufacturing process of the multilayer structure) or filled with a suitable material, such as a material that is at least optically translucent if not transparent, optionally such as glass or a plastic, such as a thermoplastic material. For example, the filling material may be optically diffusive.

[0127] The configuration of the holes 410 in the reflector design 110, and optionally other layers 412, 414, 416, can be made regular or irregular according to selected characteristics such as incident density, shape or size (e.g., diameter). For example, where the losses induced by the distance from the source are to be compensated in the outcoupled light to facilitate more uniform illumination, the incident density and / or the size of the holes preferably increase with the distance from the light source 104. At 420, a top view / plan view of the reflector design 110 and potentially another layer thereon is depicted to visualize how the configuration of the associated holes 410 can be modified spatially, for example, in response to the distance from the source 104.

[0128] Any of the holes 410 may have been produced in any of the items 110, 412, 414, 416 via perforation or otherwise in a subtractive manner including removal of material from the item to facilitate the produced hole 410. Furthermore, for example, with reference to molding and printing techniques, additive processes may be applied to produce a layer with holes. These holes may have a diameter of, for example, 50um to 200um and / or a circular shape, although other sizes and shapes are technically feasible.

[0129] Hole 410 may be a through hole, but one or more non-through holes may also be used if, for example, the remaining material at the hole location implements a semi-transparent transmissive layer, which may in any case require local bonding to a slightly lower material thickness, as is readily understood by a skilled person.

[0130] In many usage scenarios, one or more holes 410 may also be generally considered as an embodiment or at least a portion of an embodiment of the output coupling element 118, for example in combination with Fig.14 Therefore, instead of or in addition to holes, other features that cause the target element (such as a target layer) to break / deform or otherwise locally change the target element may also be used, still optionally following the principles set forth above with respect to holes, with necessary modifications.

[0131] Item 412 refers to a preferably opaque masking element or layer that may be, for example, printed (e.g., a white print), co-prepared (such as co-extruded), coated, otherwise prepared, or laminated (e.g., a film optionally laminated using pressure, adhesive, etc.) onto other elements or layers such as the reflective sheeting design 110.

[0132] Item 414 refers to a diffuser element or diffuser layer, which may be, for example, printed, co-prepared (such as co-extruded), coated, otherwise prepared, or laminated (e.g., a film optionally laminated using pressure, adhesive, etc.) onto other elements or layers such as reflective sheeting design 110.

[0133] Item 416 refers to at least one at least partially translucent (if not transparent) element or layer that may be, for example, printed, co-prepared (such as co-extruded), coated, otherwise prepared, or laminated (e.g., a film that may optionally be laminated using pressure, adhesive, etc.) to other elements or layers such as retroreflective sheeting design 110.

[0134] In addition to an aesthetic or look and feel type function, item 416 may have a protective function and / or an indicative function (it may include a graphical indicator, such as a symbol, optionally produced via printing).

[0135] As will be appreciated by one of ordinary skill, any of the previously discussed items 412, 414, 416 may be provided in the structure as an existing element, prepared in situ on the structure, or installed with the addition of one or more other items 412, 414, 416. Items 412, 414, and / or 416 may further establish at least a portion of the previously discussed items 120 or 122.

[0136] Figure 6 An embodiment is illustrated at 600 with an embedded circuit board 602 for carrying the light source 104 and potentially other electronic components and the reflector design 110 including a parabolic reflector surface 610. In some embodiments, the circuit board 602 may be omitted and the light source 104 is disposed on the substrate film 102 directly or via some other intermediate entity such as a material layer.

[0137] By disposing at least the light source 104 on the circuit board 602, a lighting module including at least the two light sources can be conveniently disposed on the substrate film 102, attached using, for example, conductive and / or non-conductive adhesives, and preferably electrically connected to the circuit design 106 thereon using, for example, conductive ink or adhesives. The circuit system on the board 602 may include a logic circuit design or sub-design, which has, for example, conductive traces or pads for connecting components (such as the light source 104) with other components or elements (such as control or communication circuits) in a desired manner at least partially on the board 602.

[0138] By utilizing the board 602, thermal management of the remaining structure can be facilitated, and for example, the wattage of one or more light sources 104 and / or some other high-power components included can be, for example, about 1 W or more, or even significantly more. Optionally, there can be multiple light sources on the board 602 with similar or different characteristics (wavelength / color, power, emission direction, beam width, technology, etc.) to each other.

[0139] The circuit board 602 may include at least one element selected from the group consisting of: a flexible film or sheet, a rigid sheet, a rectangular sheet or film, a circular or substantially circular sheet or film, an FR4-based circuit board, a metal core circuit board, a plastic substrate, a molded such as an injection molded plastic substrate, a metal substrate such as a thin sheet metal substrate, optionally having an electrically insulating layer at least selectively provided thereon, and a ceramic circuit board.

[0140] In various embodiments, the circuit board 602 or, for example, the substrate film 102 or some other substrate layer in the structure may carry various electrical components and / or other elements, such as series resistors, thermistors, white solder resist, traces, antennas, sensors, electrodes such as capacitive sensing electrodes, contact pads, integrated circuits, controllers, processors, memories, transceivers, driver circuits, optionally optically clear dope tops or other conformal coatings, and through-holes such as electrical vias, fluid vias, and / or thermal vias.

[0141] Typically, the circuit board 602 may be planar, and if its general shape is not substantially circular or oval, it is preferably circular. The size, shape, and thickness of the circuit may vary depending on the use case. Thus, for example, a rectangular shape is also possible. For example, the thickness may be a fraction or part of a millimeter (e.g., between about 0.2 mm and about 0.6 mm), a millimeter, several millimeters, or more. However, the diameter may be several millimeters, about a centimeter, or several centimeters, as well as other options. Castellations may be provided at the edges to facilitate edge connections.

[0142] For example, in the case where the circuit board 602 itself is not made of a translucent or transparent material, the circuit board 602 may be provided with at least a number of holes 603, so that the light emitted by the source 104 and reflected from the parabolic reflector 610 can easily pass through to the environment and, for example, potential users 113 therein, without undesirable problems, such as shadows in the obtained light distribution. Naturally, in embodiments that do not include a parabolic reflector 610, the concept of using a circuit board preferably provided with holes to accommodate the light source 104 and / or other electronic components or elements is also feasible. The holes 603 can be filled with an optically transmissive, at least translucent (if not transparent) material, for example filled with the material of the layer 108 when producing it by, for example, molding, which can optionally further fix the board 602. In the illustrated scenario, naturally, the substrate film 102 and potential layers or other elements thereon should also preferably be at least translucent at least in some places, so that light can be transmitted therethrough.

[0143] In any case, the retroreflector design 110 may preferably at least partially define a collimating retroreflector surface 610, optionally a substantially parabolic retroreflector, on the side 108a of the layer 108, which is opposite to the side 108b of the first side of the substrate film 102 that faces the light source 104. The surface 610 or retroreflector design 110 may be generally obtained, for example, via a selected coating method applied on a major surface, as discussed elsewhere herein. The parabolic major protrusion or "convex" surface shape on the surface 108a in the layer 108 may in turn be obtained during the molding and / or printing of the layer 108 via the use of a suitable mold shape or thereafter via, for example, a selected subtractive or additive treatment. The opposing surface 108b may remain smooth, which is beneficial in applications where a flat film 102 surface or, for example, an entire outer surface facing the (use) environment of the structure is desired. The associated motivations may vary, but include, for example, surface treatments that benefit from or require a substantially flat target, functionality (e.g., touch sensing), or aesthetics.

[0144] Figure 7 Another potential embodiment including a parabolic reflector surface and shape is illustrated at 700. The light source 104 has now been offset from the reflector shape to the center of the optical axis or axis of symmetry, and is therefore located beside the associated light aperture, and again, for example, undesirable shadows on illuminated surfaces on the film 102 may be avoided or at least reduced. Optionally, the circuit board 602 may also be used in such a scenario (not illustrated).

[0145] Figure 8An embodiment of an illumination assembly is illustrated at 800 that includes a plurality of mutually distinct multi-layer structures as generally discussed herein. Two or more such structures 801a, 801b may be prepared, stacked, and preferably attached (where adhesives, mechanical fixing elements, or other bonding methods may be used) together to create another functional assembly. Alternatively, the assembly 800 may be constructed in other ways, for example, layer by layer. The assembly 800 may be configured to output coupled light from each of the structures 801a, 801b via its individual, optionally at least partially non-overlapping, out-coupling regions 112a, 112b on one or more surfaces of the assembly and / or illuminated out-coupling elements 812a, 812b within and / or on the surfaces of the assembly. The outcoupling regions 112a, 112b may be associated with characteristic visual data, such as a printed or mask-based graphic provided on either of the illuminated surface layers 120, and thus independently controlled from the structures 801a, 801b and, in the case where one or more of the structures 801a, 801b include a number of independently controllable light sources 104, optionally further light output from the included light sources 104 may be used to selectively illuminate the visual data and generally make them visible to external perception. Thus, functionally complex illuminated / illuminating structures may be constructed from simpler, combinable constituent assemblies that differ or are similar to each other in structure, size, and / or included features or related functionality.

[0146] Fig. 9 An embodiment is illustrated at 900 (cross-sectional view, see AA cut line) and 901 (top / plan extraction view) in which a light emitting or illumination module is included in the structure, including at least one light source 104 (six in the illustrated example) located on a circuit board 602 (on a substrate film 102), which circuit board further potentially carries additional electronic components or optical components.

[0147] The circuit board 602 may optionally further carry an optical element, such as an optical waveguide 908, which includes an optically transmissive (transparent or at least translucent) material, such as a thermoplastic material discussed elsewhere herein, covering one or more light sources 104. However, the wall structure 902 is preferably advantageously arranged at the periphery of the circuit board 602, at least where it includes an optically transmissive and optionally transparent material. In addition, there may preferably be an air gap or filler 909 (again, preferably including a transparent or at least transparent material) between the wall structure 902 and the optical waveguide 908. The circuit board 602 may further include a number of optionally filled (translucent / transparent filled) holes 603 for enabling light to be transmitted therethrough as discussed above.

[0148] Fig.11An embodiment is illustrated at 1100 having multiple light sources 104 and other circuitry 105 such as associated control circuitry included in the structure.

[0149] The control circuitry 105 (such as a driver circuitry, a controller chip, such as a microcontroller, a microprocessor, an (other) integrated circuit, etc.) may optionally include elements that are at least partially integral with any of the light sources 104, instead of being separate from the light source 104 while still being electrically connected thereto, e.g. via the circuit design 106, or in addition to such a case. Preferably, the circuitry 105 is configured to dynamically and / or independently adjust, for example, the intensity and / or other characteristics (e.g., color distribution when applicable) of the light emission of each of at least two of the light sources 104. However, additionally or alternatively, joint control may also be enabled for two or more light sources 104. However, the circuitry 105 may be at least functionally connected to an external circuitry via wiring and connections (e.g., power data and / or power transmission).

[0150] For a light source 104 such as an LED, for example pulse width modulation (PWM) or current control may be utilized for this purpose. In the case where only a single light source 104 is present, a control circuit 105 system may also be included in the structure.

[0151] Fig.12 An embodiment including a bend in layer 108 is illustrated (at 1200 , via a cross-sectional top view, at 1202 a sketch in the AA direction, at 1204 a cross-sectional view along BB).

[0152] At least layer 108 does define a bend, optionally having a bend angle of about 10 degrees or more, and even potentially about 30 or 45 degrees or more, and at least a portion of retroreflective sheeting design 110 is substantially located on layer 108 at its outer periphery and / or inner periphery. Thus, reflective portions 110a, 110b, 110c, 110d have been illustrated accordingly in the figures.

[0153] By utilizing the reflector design 110, bends and other similar, more complex shapes can be implemented in the layer 108 and the general structure without substantially losing optical efficiency. In addition to the reflector design 110, TIR-type interfaces and related enabling elements or layers (e.g., layer 114) can be included in the structure to maximize the optical waveguide efficiency, which will be discussed more thoroughly elsewhere herein.

[0154] Fig.14 Different options and configurations for light output coupling are further described at 1400 in conjunction with various embodiments of the present invention, some of which have also been considered in conjunction with the description of other figures attached hereto.

[0155] Thus, several output coupling elements 118, such as layers of specific shapes and / or materials for controlling or enhancing output coupling, may be arranged, for example, in the optical path from the light source 104 towards the outside of the structure, and, for example as embedded, at the surface of the layer 108, or behind it (in the direction of the optical path).

[0156] Item 1412 refers to an output coupling element 118 that includes, for example, a layer of material and / or other output coupling features that is part of the sheeting design 110 or in a structure adjacent thereto, but includes features for enhancing light output coupling.

[0157] Thus, output coupling element 118 (including 1412) may include:

[0158] A localized recessed or raised surface, such as the surface of layer 108, optionally defining one or more, for example, prismatic recessed or raised shapes 1418;

[0159] element, or in particular, a layer 1412a of at least optically translucent (if not transparent) material having a refractive index lower than that of an optically subsequent, adjacent material (such as air), and / or a layer of opaque material that is perforated, porous or otherwise locally thinned or cut through;

[0160] An element, or specifically, a layer 1412b having holes (unfilled, or semi-transparent / transparent filled) in a carrier material (which may be opaque);

[0161] elements, or more specifically, alternating layers 1412c of higher refractive index material 1414 and lower refractive index material 1416; and

[0162] The adhesive or adhesion-promoting primer is preferably substantially optically transparent or at least translucent (capable of serving as a covering material).

[0163] Fig.15 An embodiment of a multi-layer structure (or system of structures) incorporating supplemental functionality in addition to illumination, such as touch or gesture sensing (optionally touchless), is illustrated at 1500. The supplemental functionality may be provided via additional layers and other elements disposed on the multi-layer structure including the light source 104 and other optical features, for example, as an integral construction or layer by layer.

[0164] For example, a diffusion element 414, such as a film or coating, may be provided.

[0165] Preferably, at least translucent or substantially transparent, substantially planar electrodes 418 may be provided, optionally printed, on diffuser 414 or other adjacent element or layer (e.g., 416b). Electrode 418 may be electrically or electromagnetically connected to other circuitry 105, such as drive or sense circuitry also located in the structure and / or external thereto. Electrical wiring or wireless connections may be applied for this purpose.

[0166] As described above, item 416 refers to at least one at least partially translucent (if not transparent) element or layer, which may be, for example, printed, co-prepared (such as co-extruded), coated, otherwise prepared or laminated (e.g., a film laminated optionally using pressure, adhesive, etc.) on other elements or layers such as reflective sheeting design 110. For example, item 416 may thus include, for example, printed graphics 416a, optionally laterally adjacent electrodes 418 and / or optionally protective outer surface elements 416b of translucent, opaque type, which still preferably achieve externally perceptible backlighting (i.e., not completely opaque). Item 416 may include (perforated, thinned (thinned) or otherwise treated, configured or selected to achieve at least partially translucent / transparent) plastic, metal or wood, leather or other biological material, ink, fabric, etc.

[0167] Fig.10 A flow chart of an embodiment of a method for manufacturing an integrated optically functional multilayer structure according to the present invention is shown at 1000. Since applicable manufacturing processes and related features of possible constituent elements and materials of various embodiments of the structure have also been discussed above, these discussions need not be repeated here in order to facilitate the entire already lengthy method description to be clear. However, a person of ordinary skill will understand such facts, that is, he can return to the previous paragraphs to find valuable details also about applicable manufacturing methods and considerations, and this also applies to the opposite direction in terms of structural or functional details potentially included in the multilayer structure.

[0168] At the beginning of the method for manufacturing a multilayer structure, a startup phase 1002 may be performed. During startup, necessary preparation tasks such as material, component and tool selection, acquisition, calibration and other configuration tasks may be performed. Special attention must be paid to the fact that the individual components and material selections work together and are subjected to the selected manufacturing and installation processes, which are naturally preferably pre-checked based on the manufacturing process specifications and component data sheets or through, for example, investigations and testing of the resulting prototypes. Equipment such as molding, in-mold decoration (IMD), lamination, bonding, (thermo) forming, electronic assembly, cutting, drilling, perforation, printing and / or measurement, such as the provision of required optical measurement equipment and others can thus be quickly ramped up to an operational state at this stage.

[0169] At 1004, at least one, preferably flexible, substrate film of plastic or other material for housing, for example, a light source and potentially other electronic components is obtained. The substrate film may initially be substantially flat or, for example, curved. The substrate film may be at least primarily a substantially electrically insulating material. Off-the-shelf components may be obtained, for example, rolls or sheets of plastic film for use as the substrate material. In some embodiments, the substrate film itself may first be homemade by molding from a selected starting material using a mold or molding device or other method. Optionally, the substrate film may be further processed at this stage. For example, it may be provided with holes, notches, recesses, cutouts, etc.

[0170] Item 1014 generally refers to the provision of a retroreflective sheeting design. As will be appreciated by the skilled person based on the foregoing considerations herein, the retroreflective sheeting design or portions thereof may be provided to the structure at different stages of the process, either via installation or in-situ manufacturing, depending not only on the configuration of the retroreflective sheeting design itself, but also on other elements in the structure and their configuration. However, since the retroreflective sheeting design or portions thereof may also be provided ready-made for integration with other elements such as films or generally material layers, in some embodiments, item 1014 may be integrated with other items. For example, a composite element, e.g. of a multilayer type, for implementing a substrate for electronic components and a reflective structure or layer may already be available at 1004. In some embodiments, at least a portion of the retroreflective sheeting design may be manufactured or at least attached to an optically transmissive plastic layer (or an assembly containing a transmissive layer and potentially another layer), which itself may optionally be of a pre-fabricated or separately manufactured type, rather than, for example, being molded in-situ directly on a substrate film. When a pre-fabricated plastic layer is provided on a substrate film, the plastic layer may already include at least a portion of the retroreflective sheeting design configured thereon (e.g., see for illustration Figure 1 Item 110e) at 150.

[0171] Thus, by way of non-exhaustive example, the curved arrows indicate that the order of the method items pointed to may be reversed and / or the items may be combined or further split, depending on the specific embodiment being discussed.

[0172] For example, the reflector design and related material layers may typically be provided via printing, coating, lamination or molding. However, the process may include forming various features (such as holes) in the reflector material and potentially filling them with other materials, or providing output coupling elements as discussed in more detail above. For example, the reflector design may include one or more material layers, optionally including a stack of material layers and / or conductive and / or metallic material layers. However, the reflector design (such as its layers) may include or be arranged with other elements, such as openings (holes). The reflector design is configured to reflect, optionally primarily by specular reflection, light emitted by at least one light source included in the structure to be manufactured and optionally incident on the reflector design and, in the most common use case, toward the plastic layer 108 provided at item 1012.

[0173] Prior to providing the plastic layer, at least a portion of the retroreflective sheeting design, such as one or more layers, may be provided on the substrate film, see item 1014A. Alternatively or additionally, at least a portion of the retroreflective sheeting design may be provided after or while the plastic layer is disposed on the substrate film or between the substrate film and another film (potentially another substrate film) to reside on the other side of the established intermediate plastic layer 108, see item 1014B.

[0174] However, the two unidirectional dashed arrows shown further indicate options for providing additional or alternative process aspects of reflective design 1014 substantially between items 1008 and 1010, and / or between items 1010 and 1012, or in combination with any of the three items.

[0175] At 1006, preferably via one or more additive techniques such as printed electronics or 3D printing, a number of electrically conductive and optionally thermally conductive elements defining, for example, various wires (traces), sensing elements (such as electrodes) and / or contact areas (such as pads) to construct a circuit design are provided on one or more of the substrate films. Thus, the circuit design may include several circuits or circuit sub-designs on different layers of the entire structure, optionally connected via conductive wiring (e.g., via or around the edge of the structure). For example, screen, inkjet, elastic relief printing, gravure printing or offset printing may be applied via one or more printing devices suitable for producing at least a portion of the circuit design. In some cases, subtractive or semi-additive processes may also be used. Further actions of growing the substrate film involve, for example, printing or generally providing graphics, visual indicators, optical elements (such as masks or output coupling elements), holes / fillers, etc. on or at it, if not already performed, then may be performed here, for example at 1004.

[0176] In various embodiments, the electrically conductive and optionally thermally conductive elements (traces, pads, connecting elements, electrodes, etc.) may include at least one material selected from the group consisting of: conductive ink, conductive nanoparticle ink, copper, steel, iron, tin, aluminum, silver, gold, platinum, conductive adhesive, carbon fiber, graphene, alloys, silver alloys, zinc, brass, titanium, solder, and any components thereof. For example, the conductive material used may be optically opaque, translucent, and / or transparent at at least a portion of a desired wavelength, such as visible light, so as to shield radiation, such as visible light, or have the radiation reflected from it, absorbed therein, or pass through it. This approach has also been discussed elsewhere herein. Dupont TM ME602 or ME603 conductive inks are used as practical examples of viable conductive materials.

[0177] At 1008, additional circuitry, such as one or more commonly available components including electronic components such as various SMDs, is attached to the contact areas on the film, for example, via solder and / or adhesive. For example, depending on the embodiment, a light source (e.g., LED) of the selected technology and packaging contemplated above and different elements for controlling and / or driving electronic components, connectivity, sensing, connection (e.g., connectors), carrying (circuit board, carrier, etc.) and / or power supply (e.g., battery) may be provided herein.

[0178] For example, suitable pick-and-place or other mounting devices may be used for this purpose. Alternatively or in addition, printed electronics techniques may be applied to actually fabricate at least a portion of a component, such as an organic LED (OLED), directly in situ onto a film. Thus, as will be appreciated by one of ordinary skill, the execution of items 1006, 1008 to provide a multilayer structure with the desired circuitry may overlap in time. However, the components prepared or mounted herein may also include various optical elements, such as lenses, reflectors, diffusers, masks, filters, and the like.

[0179] Non-conductive and / or conductive adhesives can be used to fasten components. In some embodiments, mechanical fastening is implemented or at least enhanced via non-conductive adhesive materials, while solder or other highly conductive (but to a lesser extent, adhesive type) materials are used for electrical connections.

[0180] Selected components may be subjected to further processing, such as encapsulation (see, eg, the review related to overcoating provided earlier herein).

[0181] Item 1009 specifically refers to the preparation and attachment of one or more at least partially pre-prepared modules (such as the above-mentioned light-emitting modules or other "sub-assemblies" having at least one light source 104 and, for example, a circuit board 602), which modules may have an initially separate secondary substrate, such as a circuit board, having a local circuit design and electronic components, such as a number of light sources, ICs and / or various other elements or components, such as optical or structural components (e.g., wall structures, diffusers, lenses, carrier elements, etc.), as also considered in more detail earlier in this document.

[0182] At least part of the electronic components and / or other elements of the final multilayer structure can thus be conveniently provided to the substrate film via a fully or partially prefabricated module or subassembly / assemblies. Optionally, the module or subassembly under consideration can be at least partially overmolded or generally covered by a protective material (such as a plastic layer) before being attached to the main substrate.

[0183] For example, adhesives, pressure, and / or heat may be used for mechanical bonding of the module or subassembly to the primary (master) substrate. Solder, wiring, and conductive inks are examples of suitable options for providing electrical and / or thermal connections between components of the module or subassembly and remaining electrical and / or thermal components on the master substrate. Item 1205 may also be performed, for example, on items 1204 or 1208. The locations shown are therefore primarily illustrative only.

[0184] Furthermore, the circuit system included in the multilayer structure (for example, on the substrate film) may include at least one component or element selected from the group consisting of: electronic component, electromechanical component, electro-optical component, radiation emitting component, light emitting component, light emitting diode (LED), organic LED (OLED), side-emitting LED or other light source, top-emitting LED or other light source, bottom-emitting LED or other light source, radiation detecting component, light detecting or photosensitive component, photodiode, optoelectronic crystal, photovoltaic device, sensor, micromechanical component, switch, touch switch, touch panel, proximity switch, touch sensor, atmosphere sensor, temperature sensor, pressure sensor, humidity sensor, gas sensor, proximity sensor, capacitive switch, capacitive sensing devices, projected capacitive sensors or switches, single-electrode capacitive switches or sensors, capacitive buttons, multi-electrode capacitive switches or sensors, self-capacitive sensors, mutual capacitive sensors, inductive sensors, sensor electrodes, micromechanical components, UI elements, user input elements, vibration elements, sound generating elements, communication elements, transmitters, receivers, transceivers, antennas, infrared (IR: infrared) receivers or transmitters, wireless communication elements, wireless tags, radio tags, tag readers, data processing elements, microprocessors, microcontrollers, digital signal processors, signal processors, programmable logic chips, application-specific integrated circuits (ASIC: application-specific integrated circuits), data storage elements and electronic component subassemblies.

[0185] In some embodiments, prior to or upon item 1012, a substrate film, optionally already containing electronic components (such as a circuit design and / or at least a portion of a light source or other circuitry), may be optionally formed 1010 using, for example, thermoforming or cold forming to exhibit a desired shape, such as an at least partially three-dimensional (substantially non-planar) shape. An applicable former device, such as a thermoformer, may be used for the purpose. Additionally or alternatively, at least some forming may be performed after molding where a multi-layer stack has been built to be subjected to such processing.

[0186] At 1012, at least one optically transmissive plastic layer or generally layer 108 is disposed or created directly on at least a first side of the substrate film and preferably on the light source thereon, the plastic layer at least laterally surrounding or adjacent to (see e.g. Fig. 9 ), optionally also at least partially covering (e.g. Figure 1) light source. In some embodiments, in addition to or instead of in-situ production of layer 108 from raw material on the first side of the substrate, an at least partially pre-fabricated (e.g. pre-molded) layer 108 may be used, wherein layer 108 may optionally then be (pre)configured with a number of features 103, such as holes (blind holes and / or through holes), for conveniently accommodating at least parts of light sources and / or other elements (e.g. (other) electronic components). Features (such as grooves or holes) may be configured in layer 108 via subtractive techniques such as cutting (engraving, milling, drilling or other machining processes). Alternatively or additionally, these features may be directly or inherently prepared in layer 108 during (in-situ) manufacturing (such as molding thereof), for example potentially eliminating the need to utilize subtractive techniques to remove layer 108 material that is later used to provide these features. However, as already mentioned above, a pre-fabricated embodiment of layer 108 can also provide at least a portion of the retroreflective sheeting design, for example by lamination, printing or coating, before layer 108 is joined to the rest of the resulting multilayer structure, such as substrate film 102 (see also Figure 1 Item 110e at 150, as an example).

[0187] Preferably, the provided plastic layer or layers (preferably comprising a thermoplastic or, in some embodiments, optionally a thermosetting layer) are thus laminated or manufactured in situ on the substrate via molding (such as injection molding). Considering, for example, the covering part of a light emitting module or other module intended to carry replaceable or generally accessible (e.g., detectable or reprogrammable) components, the required parts can be kept clear of the material or subsequently cleaned with a mechanical or chemical treatment. This module may then also include a (re)movable covering part for providing access to its internal components.

[0188] For example, the molding material may be provided using several molding steps or injection or via a single step, wherein the molding material may even flow through the substrate film from one side thereof to the opposite side, optionally via holes made therein or via penetration of the substrate material itself (e.g., via thinning / thinner portions). The molding material may be at least predominantly electrically insulating, and in many embodiments preferably is at least predominantly electrically insulating. Adhesion promoting materials may be used on the film adjacent to the molded plastic.

[0189] In practice, at least one substrate film already provided with several features (such as circuit systems including light sources, modules, other optical features, etc.) can be used as an insert in an injection molding process using at least one molding machine. In the case of using two films, the two films can be inserted into their own half-mold so that the plastic layer is at least injected between them. Alternatively, the second film can then be attached to the assembly of the first film and the plastic layer through a suitable lamination technique, for example with an adhesive in between.

[0190] For example, some of the optical elements considered above, such as lens structures, optical output coupling elements or diffusers, may be at least partially created during molding from any of the used (thermoplastic) materials and / or film inserts via appropriate mold shapes.

[0191] Instead of or in addition to moulding, the plastic layer may be produced using (3D) printing, for example.

[0192] With regard to the resulting total thickness of the obtained stacked multilayer structure, this thickness depends, for example, on the materials used and the associated minimum material thickness that provides the necessary strength in view of manufacturing and subsequent use. Such approaches are to be considered on a case-by-case basis. For example, the total thickness of the structure may be of the order of a few millimeters, as discussed elsewhere herein, but considerably thicker or thinner embodiments are also feasible.

[0193] In some embodiments, materials other than plastic may be used in layer 108, such as glass.

[0194] Item 1016 refers to several potential additional tasks, such as post-processing and installation tasks. Other layers, single or multiple films or generally additional features may be added to the multilayer structure via molding, printing, lamination, etc., for example, via heat, adhesive or pressure or suitable coating (e.g., deposition) processes and other possible positioning or fixing techniques and subtractive techniques (such as lasers). Instead of or in addition to plastics, these layers may have protective, indicative and / or aesthetic value (graphics, colors, patterns, text, digital data, etc.) and contain, for example, textile, leather or rubber materials.

[0195] Depending on the embodiment, additional elements such as electronic components, modules, module internals or parts and / or optics may be mounted and fixed, for example, at the outer surface of the structure, such as the outer surface of the included film or molded layer. For example, optical features such as lens structures or diffusers may be constructed or completed here by processing the thermoplastic layer or any other layer or element thereon by adding material thereto or removing material therefrom (laser processing is one option).

[0196] Features potentially present in the multilayer structure include, in fact, the various previously discussed features, such as diffusers, output coupling elements, masks, holes, graphics, protective and / or aesthetic (and / or tactilely preferred) films or layers, etc. Such features may be provided at this stage or during any of the previous method items, depending on their location and generally configuration in the resulting structure and other features to be included, as will be understood by those of ordinary skill.

[0197] The target material, such as a substrate film, another film (e.g., 114, 116, 120, or 122), and / or the material of the reflective sheeting design, may be modified via deformation (optionally involving material stretching) to provide features such as the output coupling elements discussed above that are integrally or monolithically formed in the target material. For example, mechanical compression introduced via a press may be used for the purpose. Deformations such as material stretching, breaking, and / or undulations caused by mechanical pressure occurring inside the structure or on a predetermined back side of the structure (e.g., not visible during use) need not have any effect on the externally perceptible vision of the structure.

[0198] In addition, the feature to be potentially provided in the structure via the method, optionally as a coextruded film layer, or via coating, printing or molding discussed above, is or includes at least one further material layer having a lower refractive index than the plastic layer, so that the at least one further material layer is optically connected to the plastic layer, optionally physically adjacent. Thus, at least a portion of the light emitted by at least one light source, propagating within the plastic layer and incident on the at least one further material layer is reflected (returned) into the plastic layer, or if the relevant critical angle is exceeded, it is substantially maintained there via total internal reflection. The at least one further material layer may optionally include a thermoplastic material or an optically transparent adhesive material or, for example, a primer.

[0199] Furthermore, the method may include at least one production or installation action selected from the group consisting of:

[0200] - laminating two or more layers comprised in the multilayer structure together via a pressure sensitive adhesive, an optically clear adhesive, a solvent, an ink, heat, pressure or a hot melt adhesive;

[0201] - additively producing, such as printing or 3D printing, at least one layer, such as a plastic layer, at least one reflective layer, another material layer, an optical waveguide, an optical output coupling element, a diffuser and / or other optical functional elements; and - providing a top-emitting light source (optionally an LED) on the side of the substrate film, so that its contact pad faces the lateral direction of the substrate film surface, and the contact pad is electrically connected to the circuit design via a conductive adhesive contact also provided (for example, allocated) on the substrate film, and the conductive adhesive is at least partially surrounded by the substrate film via a structural adhesive provided on the substrate film (this is a feasible way to operably transform the top light source into a side light source).

[0202] Even further, the method may comprise interconnecting a plurality of modules together to construct a structure, wherein any or each module advantageously comprises

[0203] At least one of the following

[0204] - one or more light sources;

[0205] - at least a portion of a substrate film; and

[0206] - Circuit design, optionally including light source driver circuit and / or capacitive sensing electrodes;

[0207] or

[0208] At least a portion of the reflective sheeting design layer and / or at least a portion of the plastic layer.

[0209] For example, an electronic component and / or lighting module (comprising, for example, a light source, a circuit design and optionally another circuit system, such as a control circuit) as well as several simpler modules that do not have, for example, electronic components but include, for example, optically transmissive and / or reflective materials or structures can be produced and then joined together.

[0210] Any of the modules may span several layers of the multilayer structure.In addition to being able to construct a multilayer structure at least in part from modules of different characteristics, several optionally mutually different or similar multilayer structures may be connected to create an even larger, more functionally diverse collection.

[0211] If capacitive sensing such as touch on the structure or touchless gestures is optionally implemented, the sensing electrodes of the circuit system can be configured (sized, positioned, etc.) with other elements and layers, see Fig.15 and related text so that its sensing area or volume defined by, for example, associated electric or electromagnetic fields is positioned as desired and thereby covers, for example, areas on the top surface of the structure, and / or other areas that should be sensitive to touch (and / or in some embodiments, touchless gestures) or other sensing targets. This type of configuration can be achieved or performed, for example, through the use of simulations or measurement activities. For example, the necessary features can be built onto an existing structure in a layer-by-layer manner, or installed as an at least partially ready-made stack.

[0212] If provided, the connectors of the multilayer structure or system can be connected to a desired external connection element, such as an external connector of an external device, system or structure (e.g., a host device). For example, these two connectors can together form a plug and socket type connection and interface. The multilayer structure or system can also be generally positioned and attached to a larger system herein, such as an electronic host device, optionally a personal communication device, a computer, a household appliance, an industrial device, or a vehicle, for example, in embodiments where the multilayer structure establishes a portion of the exterior or interior of a vehicle (such as a dashboard or panel).

[0213] At 1018, method execution ends.

[0214] The scope of the present invention is determined by the appended claims together with their equivalents. Those of ordinary skill will appreciate the fact that the disclosed embodiments are constructed for illustrative purposes only and that other configurations applying many of the above principles can be easily prepared to best suit each potential usage scenario.

Claims

1. An integrated optically functional multilayer structure (100, 200, 300, 400, 500, 600, 700, 800, 900, 1100, 1300, 1400, 1500) suitable for large-area dynamic lighting, comprising: A flexible, optionally 3D formable and thermoplastic substrate film (102, 102a) arranged with a circuit design (106) comprising at least a number of electrical conductors; and a plurality of top-emitting (104a), bottom-mounted light sources (104) disposed on a first side of the substrate film to internally illuminate (104a) at least a portion of the structure for external perception via associated outcoupling regions (112, 112a, 112b, 112c), For each of the plurality of light sources, there is provided, optionally at least partially, a common an optically transmissive plastic layer (108), which is optionally made of a thermoplastic material and is disposed on the first side of the substrate film, the plastic layer at least laterally surrounding or adjacent to the light source, and optionally also at least partially covering the light source, the substrate film optionally comprising the same material or material layer as the plastic layer, or at least having a similar or lower refractive index as the plastic layer; and A reflective sheet design (110) comprises at least one material layer, which is disposed at least on (110b; 110c) the light source and is configured to reflect light emitted by the light source and incident on the reflective layer toward the plastic layer, optionally mainly through specular reflection.

2. The structure of claim 1 wherein the retroreflective sheeting is designed to have a reflectance of at least locally about 75%, preferably at least about 90%, and most preferably at least about 95% at selected, optionally substantially all visible light wavelengths.

3. A structure according to any of the above claims, wherein (300, 900) the reflector design (110, 110a, 110b) is configured in a preferably direct light emission path from at least one of the plurality of light sources, so that light input coupled into the plastic layer from the light source and incident on the reflector design is reflected to be preferably more aligned with a side plane of the plastic layer that is substantially transverse to the surface normal of the plastic layer.

4. A structure according to any of the preceding claims, wherein the reflector design is arranged on or in the plastic layer to reflect and direct light emitted by at least one of the plurality of light sources and incident on the reflector design, so that it propagates toward an output coupling region (112, 112a, 112b, 112c), and optionally further toward a related surface normal of the plastic layer, so that the light is at least output coupled from the plastic layer or the overall structure.

5. A structure according to any of the preceding claims, wherein the reflector design (110, 110a, 110b, 110c) at least partially comprises a material stack of a plurality of superimposed material layers having at least two mutually different refractive indices, optionally defining a Bragg mirror.

6. A structure according to any of the preceding claims, wherein the retroreflective sheeting design comprises at least one element selected from the group consisting of: Conductive materials; Metal, optionally metal particles, which are further optionally disposed on or within the substrate film or another film or layer comprised in the structure; Thin film coatings, optionally PVD (Physical Vapour Deposition) coatings; and ·Ink or paint.

7. A structure according to any of the above claims, wherein one or more portions of the reflective sheeting design (110) are located on a side of the plastic layer, the side being identical (110a), opposite (110b) and / or transverse (110c) to a side facing the first side of the substrate film carrying at least one of the plurality of light sources (104).

8. A structure according to any of the preceding claims, comprising at least one further, optionally printed, material layer (114), optionally stacked on and preferably in contact with the reflective sheeting design (110, 110a, 110b, 110c), the at least one further material layer having a lower refractive index than the plastic layer, the at least one further material layer being optically connected to the plastic layer, optionally physically adjacent to the plastic layer, so that at least a portion of the light emitted by at least one of a plurality of light sources, propagating within the plastic layer and incident on the at least one further material layer is deflected back into the plastic layer via total internal reflection, the at least one further material layer optionally comprising or consisting of an optically clear adhesive or primer.

9. A structure according to claim 8, wherein the layer of the at least one additional material layer (114) is a multilayer, optionally co-extruded type layer of the substrate film (102a), which also comprises a carrier layer (102) for the light source (104).

10. A structure according to claim 8 or 9, comprising an intermediate layer (116) between the plastic layer (108) and the layer of the at least one additional material layer (114), the intermediate layer comprising an optically transmissive material, the optically transmissive material preferably comprising the same material as the plastic layer or having a refractive index at least similar thereto, the intermediate layer and the at least one additional material layer optionally being parts of a multilayer film (116a), further optionally being a preferably co-extruded multilayer film and / or a substrate-type multilayer film, carrying a number of elements such as optical elements, circuit designs or one or more electronic components, laminated on the plastic layer.

11. A structure according to any one of claims 8 to 10, wherein at least a portion of the reflective sheeting design (110, 110a, 110b) and the at least one additional material layer (114) are located on the same side, opposite side or both sides of the plastic layer (108).

12. A structure according to any one of claims 8 to 11, wherein the layer of the reflective sheeting design (110), the layer of the at least one additional material layer (114) and the plastic layer (108) are at least partially superimposed in terms of their materials, so that the material of the layer of the at least one additional material layer is stacked between the layer of the reflective sheeting design and the material of the plastic layer.

13. A structure according to any of the above claims, wherein (1200) the plastic layer defines a bend, the bend optionally having a bend angle of about 10 degrees or greater, and at least a portion of the reflective sheeting design is substantially located on the plastic layer at its outer periphery and / or inner periphery.

14. A structure according to any of the above claims, wherein (400, 420, 1400, 1412, 1412b) at least a portion of the reflector design includes a plurality of holes (410), such as perforations, and the plurality of holes are optionally provided with an optically transmissive and optionally further optically scattering filler to enable incident light to propagate through for output coupling, wherein the incident density and / or the size of the holes preferably increases with the distance from at least one of the multiple light sources.

15. The structure according to any of the preceding claims, comprising (1500) at least one element, preferably along a light path from one or more of the plurality of light sources towards the exterior of the structure, the at least one element being selected from the group consisting of: Diffuser (414); a preferably at least translucent or substantially transparent, substantially planar electrode (418), optionally printed on the diffuser; a printed pattern (416, 416a), which optionally laterally adjoins the electrodes; and • Protective outer surface element (416, 416b), optionally of translucent, non-transparent type.

16. A structure according to any of the preceding claims, wherein (600, 700) the reflector design at least partially defines at least one collimating reflector surface (610), optionally substantially a parabolic reflector, preferably on a side of the plastic layer opposite to a side of the substrate film facing the first side carrying at least one of the plurality of light sources, At least one of the plurality of light sources (104) is preferably centered (600) or off-center (700) relative to an axis of symmetry of the surface of the collimating reflector.

17. A structure according to any of the preceding claims, wherein the reflective sheeting is designed to contain a locally treated, preferably mechanically, chemically or electrically treated, optionally deformed such as an elongated portion, such as a material stack portion or a material layer portion, which has altered reflective properties for light redirection and optionally output coupling (118) through the plastic layer.

18. A structure according to any preceding claim, wherein the plastic layer locally defines surface features or surface patterns, optionally comprising roughened or deformed areas, for out-coupling (118) light internally incident thereon.

19. The structure according to any of the preceding claims, comprising (500) on the plastic layer a number of preferably printed, optionally dispersed output coupling elements (118), said output coupling elements having spatially varying incidence densities and / or sizes, preferably including at least thickness, The incident density, thickness and / or one or more other dimensions of the output coupling element preferably increase with distance from at least one of the plurality of light sources to individually enhance output coupling with distance, and one or more of the plurality of output coupling elements optionally include fluorescent, phosphorescent, thermochromic or photochromic materials.

20. The structure of any preceding claim, comprising an outer coating (124) at least partially covering a light emitting portion of at least one of the plurality of light sources, the outer coating comprising an optically transmissive material optionally having a higher refractive index than the plastic layer.

21. A structure according to any of the preceding claims, comprising (200) a light outcoupling region (112, 112a, 112b, 112c) on the plastic layer, wherein at least one of the plurality of light sources (104) is located between at least a portion of the reflector design (110c) which is preferably aligned substantially perpendicularly to the light outcoupling region and the light outcoupling region, and the at least one of the plurality of light sources is aligned towards the at least a portion (110c) of the reflector design according to its main emission direction.

22. A structure according to any of the above claims, comprising a circuit board (600, 900) carrying at least one of the multiple light sources and arranged on the substrate film, wherein the circuit board optionally further carries an optical waveguide (908) made of an optically transmissive material covering the at least one light source, a wall structure (902) made of an optically transmissive and optionally transparent material arranged at the periphery of the circuit board and / or an air gap or filler (909) preferably between the wall structure and the optical waveguide, and / or the circuit board further optionally comprises a plurality of holes (603) for enabling light to be transmitted therethrough.

23. A structure according to any of the preceding claims, comprising, in the light path from at least one of the plurality of light sources towards the exterior of the structure and at or behind the surface of the plastic layer, at least one element selected from the group consisting of: an optical print layer; a coating or film comprising an opaque or translucent material (416, 416a, 416b) with respect to light emitted by at least one of the plurality of light sources; a light shield (412); a recessed surface, such as a surface of the plastic layer, optionally defining one or more prismatic recessed shapes (118; 1418); a layer of at least translucent material having a lower refractive index than an optically subsequent, adjacent material such as air, if not optically transparent; alternating layers (1412, 1412c) of higher (1414) and lower (1416) refractive index material; a perforated, porous or otherwise locally thinned or cut through layer of an opaque material; and an adhesion promoter primer.

24. A structure according to any of the above claims, wherein at least one of the plurality of light sources comprises a semiconductor, a packaged semiconductor, a chip-on-board package semiconductor, a bare chip, an electroluminescent or printed light source, preferably an LED, optionally a multi-color such as an RGB (red, green, and blue) LED.

25. A structure according to any of the preceding claims, comprising a control circuit (105), optionally at least partially integrally formed with any one of the plurality of light sources (104), for dynamically and independently adjusting the luminous intensity of at least two of the plurality of light sources.

26. A structure according to any of the above claims, wherein the optically transmissive plastic layer (108) defines a hole (103) therein for accommodating at least a portion of at least one of the plurality of light sources, optionally a plurality of holes, each of which is configured to accommodate one or more light sources.

27. A structure according to any of the above claims, wherein at least one of the several electrical conductors (106a) of the circuit design (106) is partially or substantially positioned on a side of the reflective sheeting design facing away from the optically transmissive plastic layer (108), and is preferably at least electrically and optionally physically connected to the light source (104).

28. A structure according to any of the preceding claims, wherein (150) at least a portion (110e) of the reflective sheeting design (110) is located between the optically transmissive plastic layer (108) and the substrate film (102), optionally fabricated or laminated to the optically transmissive plastic layer (108).

29. A multi-source, multi-target illumination system (800), comprising two or more structures (801a, 801b) as described in any of the above claims stacked, preferably attached together, the system being configured to output couple light from each of the two or more structures via their respective, at least partially non-overlapping output coupling regions (112a, 112b) onto one or more surfaces of the system and / or onto illuminated output coupling elements (118; 812a, 812b) in or on the system.

30. A method (1000) for manufacturing an integrated optically functional multilayer structure, comprising: Obtaining (1004) a flexible, optionally 3D formable and thermoplastic substrate film (102), which is optionally a multilayer film, provided (1006) with a circuit design, the circuit design comprising at least a number of electrical conductors, preferably additively produced, optionally printed on the substrate film; Arranging (1008, 1009) a plurality of top-emitting (104a) and bottom-mounted light sources (104) disposed on a first side of the substrate film; For each of the plurality of light sources, on the first side of the substrate film, optionally via molding, lamination or 3D printing, an optically transmissive plastic layer is provided (1012), optionally at least partially shared, the plastic layer at least laterally surrounding or adjacent to, optionally also at least partially covering, the light source; wherein A reflective sheet design is provided (1014, 1014A, 1014B), which includes at least one material layer, wherein the material layer optionally includes a stack of material layers and / or a layer of conductive and / or metallic material, optionally including printing, coating, lamination or molding, and the reflective sheet design is configured to reflect light emitted by the multiple light sources and incident on the reflective sheet design preferably toward the plastic layer, optionally mainly through specular reflection.

31. The method of claim 30, comprising providing at least one additional material layer, optionally as a coextruded film layer or via coating, printing or molding, the at least one additional material layer having a lower refractive index than the plastic layer, such that the at least one additional material layer is optically connected to the plastic layer, optionally physically adjacent, so that at least a portion of the light emitted by at least one of the plurality of light sources, propagating within the plastic layer and incident on the at least one additional material layer is diverted back into the plastic layer via total internal reflection, the at least one additional material layer optionally comprising a thermoplastic material or an optically transparent adhesive material or primer.

32. The method according to claim 30 or 31, comprising at least one step selected from the group consisting of: Laminating two or more layers included in the multilayer structure together via a pressure sensitive adhesive, an optically clear adhesive, a solvent, an ink, heat, pressure, or hot melt; Additive manufacturing such as printing or 3D printing of at least one layer such as the plastic layer, at least one reflective layer, further material layers, light guides, light outcoupling elements, diffusers and / or other optically functional elements; and A top-emitting light source, optionally an LED, among the plurality of light sources is disposed on one side of the substrate film such that its contact pad faces a direction transverse to the surface of the substrate film and is electrically bonded to the circuit design by contact with a conductive adhesive disposed on the substrate film, the conductive adhesive at least partially surrounding the substrate film via a structural adhesive disposed on the substrate film.

33. A method according to any one of claims 27 to 29, comprising interconnecting a plurality of modules, wherein each module comprises At least one of the following: o one or more light sources from the plurality of light sources; o at least a portion of the substrate film; and o the circuit design, which optionally includes a light source driver circuit and / or a capacitive sensing electrode; or At least a portion of the layer of the reflective sheeting design and / or at least a portion of the plastic layer.

34. A method according to any one of claims 30 to 33, wherein the optically transmissive plastic layer is configured to have at least one hole for accommodating at least one of the plurality of light sources, optionally a plurality of holes, each of which is configured to accommodate one or more of the plurality of light sources.

35. A method according to any one of claims 30 to 34, wherein the optically transmissive plastic layer is at least partially arranged as a prefabricated element, which is initially separated from the first side of the substrate film and is preferably provided with at least a part of the reflective sheeting design before attaching the optically transmissive plastic layer to the substrate film directly or via one or more intermediate layers.

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