Optical functional multilayer structure and related manufacturing method

Abstract

An integrated optical functional multilayer structure (100, 200, 300, 400, 500, 600, 700, 800, 900, 1100, 1300, 1400, 1500) comprising a flexible, optionally 3D-formable and thermoplastic substrate film (102, 102a) arranged together with a circuit design part (106) having at least some electrically conductive conductors preferably additionally printed on the substrate film, a light source (104) provided on a first side of the substrate film for internally illuminating at least a part of the structure for external perception (113), a light-transmissive plastic layer (108) of optionally thermoplastic material provided on the first side of the substrate film, the plastic layer surrounding the light source (104) at least laterally or adjacent to the light source (104) and optionally at least partially covering the light source (104), the substrate film optionally comprising the same material or material layer as that of the plastic layer or having at least a refractive index similar to or lower than that thereof, a reflector design part (110) comprising at least one material layer, the reflector design part being configured to reflect the light emitted by the light source and incident on the reflector design part, optionally towards the plastic layer, optionally mainly specularly. A related manufacturing method is presented.

Description

Technical Field

[0001] The present invention generally relates to a functionally integrated structure incorporating various functional features (e.g., electronic, mechanical, or optical elements). Specifically, but not exclusively, the present invention relates to the provision of such a structure comprising at least one or more optoelectronic light sources.

Background Art

[0002] In the context of various functional aggregates, for example, in the field of electronic devices and electronic products, there are various different stacked assemblies and multi-layer structures. For example, the motivation behind integrating functionality, including electronic devices, mechanical features, or optical features, can be as diverse as the associated usage scenarios. When the resulting solution ultimately exhibits multi-layeredness, component size reduction, weight reduction, cost reduction, or simply efficient integration is often required in relatively many cases. The associated usage scenarios can then relate to product packages or casings, the visual design of device housings, wearable electronics, personal electronic devices, displays, detectors or sensors, vehicle interiors, antennas, labels, vehicle electronics, etc.

[0003] Electronic devices (e.g., electronic components, integrated circuits (ICs), and conductors) can generally be provided on a substrate element by means of a plurality of different technologies. For example, off-the-shelf electronic devices (e.g., various surface mount devices (SMDs)) can be mounted on a substrate surface that ultimately forms an interface layer inside or outside a multi-layer structure. In addition, applying techniques corresponding to the term "printed electronics", electronic devices can be directly and additionally actually generated on the relevant substrate. The term "printed" in this context refers to printing techniques capable of generating electronic devices / electrical elements from printed matter, including but not limited to screen printing, flexographic printing, and inkjet printing, through a substantially additional printing process. The substrate used can be a flexible and stretchable, organic printed material, but not necessarily so.

[0004] Furthermore, the concept of injection molded structural electronics (IMSE) involves building functional devices and their components in the form of a multi-layer structure, which is about containing electronic functionality as seamlessly as possible. The characteristics of IMSE also mean that the electronic devices are generally manufactured in a true 3D (non-planar) form according to the 3D model of the product, component, or generally the entire design in question. To achieve the desired 3D layout of the electronic devices on the 3D substrate and within the associated end product, the electronic devices can still initially be provided on a planar substrate (e.g., a film) using the two-dimensional (2D) method of electronic device assembly, whereby the substrate that will already house the electronic devices is formed and overmolded into the desired three-dimensional, i.e., 3D, shape by a suitable plastic material that covers and embeds, for example, the underlying elements (e.g., electronic devices), thus protecting the elements from the environment and potentially hiding them. Of course, additional layers and elements can be added to the construction.

[0005] The optical features and functionality provided in the aforementioned integrated structure can include, for example, several light sources intended to illuminate a selected interior of the structure or the environment of the structure. The illumination can itself have different motivations (e.g., decorative / aesthetic or functional (e.g., inductive or indicative) motivations).

[0006] For example, in some usage scenarios, it is necessary to illuminate the environment to improve visibility in dim or dark conditions, which may enable various human activities (such as walking, reading, or operating a device) that typically require high lighting comfort to be carried out without problems. Alternatively, the lighting can be applied to warn or notify different stakeholders about the state of a structure or related receiving device, or a connected remote device, via different warning lights or indicator lights, and for example, related graphics. Nevertheless, the lighting can give the structure or its host a desired appearance and visually emphasize its specific area or feature by a desired color or brightness. Therefore, the lighting can also be applied to indicate to the user of the structure or its receiving device, for example, the location of different functional features (such as keys, switches, touch detection areas, or other UI (user interface) features on the device surface), or the actual function underlying the illuminated feature.

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

[0008] For example, as will be readily understood by those skilled in the art, both functional and aesthetic problems can easily occur due to unwanted light outflow or light leakage from a structure or between its different internal volumes and regions, and the transmission loss from the perspective of the desired light path and the original lighting target should not be forgotten. However, the perceptibility of the light source itself is one of the potential further problems. In some applications, the light source should preferably remain hidden or be only modestly or intermittently exposed.

[0009] In addition, for example, in terms of the shape, size, or location of the illuminated surface area, achieving sufficient resolution, often dynamic or adaptive control, of the light transmitted internally and ultimately output can be at least sometimes difficult in a highly integrated structure. In various solutions, controlling or specifically improving the uniformity of that light, for example, on the light output coupling surface, which can sometimes span a rather large area in relation to the overall dimensions of the structure or its selected surface, has been found to be burdensome in the past. More generally, the same applies to the spatial control of illumination and light output coupling. This can be an important issue, for example, when the surface includes an icon or symbol that should be evenly illuminated to indicate to an external observer of the structure that the device functionality or status associated with the icon or symbol is active. Merely using multiple light sources to more effectively illuminate a common target area or feature (e.g., an icon) can still result in illumination hot spots and additional leakage, and at the same time, requires more, often precious, power and space. Obtaining an appropriate mixture of brightness or color can also be difficult, especially in lighting applications for large areas, which requires a relatively long distance between the light source(s) and the area or feature being illuminated thereby, which either increases the size of the required structure or decreases the area that can be illuminated with appropriate mixing performance.

[0010] Furthermore, several light sources (e.g., high-power LEDs), which are generally preferred in many respects, consume a rather significant amount of power (simply on the order of more than about 1 watt in magnitude), and can ultimately become hot and deteriorate or break. They can also damage nearby heat-sensitive elements (e.g., plastic substrates).

[0011] Adding a plurality of potentially complex light guiding, input coupling, output coupling, limiting, or generally processing elements to a structure in turn has its own drawbacks (e.g., increased space consumption, weight, and other design constraints). For example, maintaining high optical performance of a structure with respect to low leakage, loss, and similar objectives may easily further limit the shape of the structure or the elements contained therein to something that is not optimal for their intended use cases.

[0012] However, when optical features (e.g., illumination features) are combined with other features within a structure, the other features may, for example, due to their shadowing or masking effects, have an adverse impact on the lighting performance, and also, occasionally, the optical features may, for example, due to the spatial constraints faced, prevent or complicate the implementation manner of other features.

[0013] From the perspective of the manufacturing process, the adoption of various optical features in a structure, in addition to the complexity of the overall process, increases the amount of problems faced due to the (non)-compatibility of the added features with each other or with the remaining materials and features, and the associated process steps. For example, considering overmolding, it leads to an increase in failure rate / a decrease in yield. For example, when a material associated with a lower melting temperature (e.g., polymethyl methacrylate, PMMA) is utilized together with a molding material with a higher melting temperature (e.g., polycarbonate, PC), features printed or established on the lower melting temperature material may deteriorate or be washed away during molding. SUMMARY OF THE INVENTION

[0014] An object of the present invention is to at least mitigate one or more of the drawbacks associated with known solutions in the context of an optically integrated structure and related manufacturing methods.

[0015] This object is achieved by various embodiments of an integrated functional multi-layer structure and related manufacturing methods for providing a multi-layer structure.

[0016] According to one aspect, an integrated optical functional multilayer structure preferably a flexible, optionally 3D formable, and thermoplastic, optionally single-layer or multilayer film, a substrate film, disposed together with a circuit design portion comprising at least some electrical conductors (e.g., traces and / or contact pads) preferably additionally printed on the substrate film, a light source provided on a first side of the substrate film to internally illuminate at least a portion of the structure for external perception, on the first side of the substrate film, preferably provided (e.g., laminated or produced) to the light source, preferably shaped, among many possible options, an optically transparent plastic layer of a thermoplastic material (e.g., polycarbonate), the plastic layer surrounding or adjacent to the light source laterally and also optionally at least partially covering, the substrate film optionally comprising the same material or material layer as that of the plastic layer or having at least a similar or lower refractive index than that, a plastic layer, a reflector design portion comprising at least one material layer optionally containing an electrically conductive material, the reflector design portion being configured to reflect light emitted by the light source and incident on the reflector design portion, preferably towards the plastic layer.

[0017] In a further aspect, a method for manufacturing an integrated optical functional multilayer structure is to obtain a substrate film preferably flexible, optionally 3D formable, and thermoplastic, optionally a multilayer film, the substrate film preferably provided with a circuit design portion comprising at least some electrical conductors (e.g., traces and / or contact pads) preferably additionally produced (e.g., printed) on the substrate film, to obtain the substrate film, to dispose at least one light source on a first side of the substrate film, Optionally, through lamination or generation (e.g., molding or 3D printing), providing a light-transmissive plastic layer on a first side of the substrate film, preferably to the at least one light source, the plastic layer surrounding or at least adjacent to the light source at least laterally and optionally at least partially covering it, such that the plastic layer potentially at least partially embeds the light source. Optionally, a reflector design part is provided with at least one material layer, which includes a stack of material layers and / or preferably a layer of an electrically conductive material and / or a metallic material, which optionally includes printing, coating, lamination, or molding, and the reflector design part is configured to reflect light emitted by the at least one light source and incident on the reflector design part, preferably towards the plastic layer, optionally mainly specularly.

[0018] This solution provides different advantages over a variety of previously applied solutions, of course depending on each of their embodiments.

[0019] For example, the input coupling, transmission, and (output) coupling of light are effectively controlled by a clever connection configuration of the materials and elements (e.g., light sources) involved, for example, with respect to their relative positioning, orientation, dimensions, and other characteristics, and there can be associated optical efficiencies and various other characteristics of interest optimized in the associated optical structures (e.g., the achieved lighting uniformity). This solution is also particularly suitable for lighting applications in large areas and facilitates reducing or keeping low the number of light sources required, which has obvious advantages in terms of space savings, power consumption, structural and manufacturing complexity, weight, etc.

[0020] For example, an embedded mirror-type reflector may be arranged opposite or adjacent to a light source, using, for example, a typical conductive metallic material or a number of layers with varying refractive indices, to enable efficient transmission and control of light within a structure. However, a total internal reflection (TIR)-capable interface may complement the mirror reflector for more sophisticated and flexible control of light transmission and may be additionally configured, for example, to be stacked with the mirror reflector.

[0021] A "hide until lit" effect may also be produced. For example, a structure, various components, or a graphical symbol provided, for example, within a conductive trace, can be made invisible to external visual perception until the light source intended to illuminate and targeted at them is activated.

[0022] From a manufacturing perspective, desired features can be fabricated by skillfully applying printing and other cost-effective, flexible, and generally controllable methods (e.g., various molding and coating techniques), in addition to the use of off-the-shelf elements (e.g., films, components, or modules).

[0023] By appropriately configuring the light source(s) and, for example, the proposed reflector design, the mixing of the light characteristics on the output coupling surface along the transmissive plastic layer and on the outer surface of the structure can also generally be enhanced, thus reducing the so-called mixing distance required to achieve the desired mixing performance.

[0024] An optical element (e.g., an output coupling element) can be integrally and monolithically formed with other elements (e.g., a material layer) by locally deforming the associated material, which not only provides a very efficient optical solution but also simplifies the structure and potentially simplifies the manufacturing process among other advantages, resulting in savings in space, material, and weight. For example, the mirror effect provided by a reflector design can be locally disrupted to establish an optical output coupling element from the deformed portion, or the material(s) at a TIR enabling interface can be similarly treated to locally change the characteristics of the interface, e.g., for enhanced scattering and / or interfering TIR.

[0025] A circuit design comprising an electrical conductor for powering a light source can be cleverly positioned behind a reflector design from the perspective of light propagating within a transmissive plastic layer so as not to cause, or at least cause reduced interference (e.g., diffusion or absorption), to the propagation of light.

[0026] The adhesion between materials can be improved. For example, by using multiple layers or multi-layer elements such that materials adjacent to a typically formed transmissive layer are selected to better withstand molding and other processes and to be securely attached to each other or to the transmissive layer, the problem of washout can be reduced. For example, optionally co-extruded multi-layer films (e.g., PC / PMMA films) can be used in a stack structure above and / or below a transmissive layer containing a PC resin, and then an injection molding or other method is used on top of the PC layer of the multi-layer film or between the PC layers of two multi-layer films. However, also, for example, a printed output coupling element can be provided on a PC surface with advantageous PC surface ink in a standard and many ways. In addition, using co-extruded multi-layer films reduces the adhesion problem between different material layers because of the excellent adhesion obtained from the film co-extrusion process. Combinations of different co-extruded materials with better refractive index differences can be utilized.

[0027] The proposed multi - layer can be modular and can be assembled using a plurality of different and / or similar modules that provide different features to the aggregated structure. For example, preferably, IMSE pieces or cell - type modules shaped (e.g., hexagonal / honeycomb cells) to be simply fixed to each other like puzzle pieces can be utilized. Some module(s) may include more features or functionality, more complex functionality, more difficult - to - implement functionality, or some types of functionality (e.g., general electronic devices and / or optoelectronic devices (e.g., light sources)), while some other module(s) may be simpler and mainly include, for example, passive optics (transparent materials, reflectors, masks, etc.) or other features that can be conveniently manufactured and used, for example, to scale the size of the structure. The modules can support snap - fit connections or crimp fixes, for example, to facilitate mutual fixation. In addition to the modular single structure, several multi - layer structures can be connected together and optionally stacked to form a larger aggregate. Thus, modularity can be subtly provided at different levels and resolutions.

[0028] The different embodiments of the present invention can be generally utilized and can be included in different applications, for example, in electronic devices or devices including electronic devices such as computers, tablets, smartphones, other communication devices, wearables, AV devices, optical devices, household appliances, vehicles, displays, panels, medical devices, smart clothing, furniture, artworks, etc., but not limited thereto.

[0029] Various other benefits provided by the different embodiments of the present invention will become apparent to those skilled in the art based on the following detailed description.

[0030] As used herein, the expression "some" can refer to any positive integer starting from one (1).

[0031] As used herein, the expression "a plurality of" can each refer to any positive integer starting from two (2).

[0032] The terms "first" and "second" are used in this specification to distinguish one element from other element(s), and are not used to particularly prioritize or order them, unless otherwise specified.

[0033] The exemplary embodiments of the invention presented in this specification should not be construed as limiting the applicability of the appended claims. The verb "comprising" is used in this specification as an open limitation that does not exclude the presence of features not recited. The various embodiments, and the features recited, for example, in the dependent claims, can be freely combined with each other, unless otherwise specified.

[0034] Selected embodiments of the invention are illustrated by way of example, and not limitation, in the figures of the accompanying drawings.

Brief Description of the Drawings

[0035]

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DETAILED DESCRIPTION OF THE INVENTION

[0036] In FIG. 1, generally, an embodiment of a multilayer structure according to the present invention is illustrated at 100 via a cross-sectional sketch.

[0037] The multilayer structure includes at least one substrate film 102, which is preferably of a flexible and 3D formable (3D moldable) material (e.g., a thermoformable (plastic) material). As will be understood by those skilled in the art, instead of a single, optional monolithic film 102, there can be a multilayer and / or multi-section construction type film 102a having at least layers that are mutually different in place, for example, also including a hosting layer for electronics. Such a multilayer film 102a can be manufactured, for example, by coextrusion as part of an embodiment of the method contemplated later herein.

[0038] Item 108 preferably refers to at least one, preferably thermoplastic, at least light-transmissive layer provided by molding on a substrate film 102. Optionally, layer 108 can be produced between the substrate film 102 and any possible further element(s), or generally between material layer(s) (e.g., at least one further layer or film different from or similar to film 102). Alternatively, item 108 can refer to a plurality of stacked, preferably still thermoplastic and / or integrated layers, optionally produced by multi-shot molding. Layer 108 should be capable of transmitting light considering at least in part the wavelengths emitted by a selected light source(s) (e.g., substantially all or visible light of a selected wavelength), or generally wavelengths typically including but not necessarily limited to visible wavelengths.

[0039] Depending on the application, layer 108 comprises a first side and an associated first surface 108a that can be directed towards the use environment of the structure and, for example, a user 113 of the structure located in such an environment. Further, layer 108 comprises an opposite second side and an associated second surface 108b that essentially faces at least one instance of film 102 and potentially a receiving device or structure. However, in an alternative embodiment, surface 108b can essentially face the user of this use environment instead of or in addition to surface 108a.

[0040] Thus, since layer 108 is precisely configured to transmit or guide light, it will comprise a material that is optically at least translucent and optionally substantially transparent, and the light transmittance of the entire thermoplastic layer can, in some use scenarios, preferably be at least 50%, although the desired transmittance can, in fact, vary radically between all possible use scenarios. In some embodiments, a transmittance of at least about 80% or 90% may be preferred to maximize the light output from the structure, although in some other scenarios, for example, when problems associated with light leakage should be minimized, lower values can be quite sufficient, even if not advantageous. The transmittance is typically defined or measured in the selected direction, for example, in the main direction of light propagation and / or in the transverse direction (i.e., the thickness direction) with respect to the surface of the substrate film 102, taking into account the wavelengths of interest, which typically include visible wavelengths as discussed heretofore.

[0041] In some embodiments, the appropriate translucency or optical attenuation of layer 108 can be achieved, for example, by using scattering elements (e.g., particles) in the material used. When the amount of scattering elements increases, the scattering / diffusion and half-value angle also increase as one possible measurable metric, but the light transmittance through the layer decreases substantially. Correspondingly, when the layer thickness increases substantially, the scattering / diffusion characteristics (e.g., half-value angle) increase and the transmittance decreases.

[0042] In terms of applicable materials, layer 108 can generally comprise at least one material selected from the group consisting of, for example, polymers, organic materials, biocompatible materials, composite materials, thermoplastic materials, thermosetting materials, elastomeric resins, PC, PMMA, ABS, PET, copolyesters, copolyester resins, nylon (PA, polyamide), PP (polypropylene), TPU (thermoplastic polyurethane), polystyrene (PS or GPPS, general-purpose polystyrene), TPSiV (thermoplastic silicone vulcanizate), and MS resins.

[0043] The substrate film 102 may optionally comprise a material or material layer having the same, or a similar or lower refractive index than that of layer 108. Thus, the resulting interfaces 102, 108 may each be optically transparent or enable a total internal reflection (TIR) type function for light to reach the interface from layer 108.

[0044] In some embodiments, a colored or more strongly colored resin as the material of layer 108 provides a viable option for restricting unwanted light leakage inside and outside the structure 100 to nearby elements or to a general distance, and can hide the interior (e.g., light source 104, or other circuit configurations) from external perception. An originally optically substantially clear base material (e.g., PC or other plastic resin) can be doped with a colored masterbatch. In many usage scenarios, the structure 100 should be, for example, only a few millimeters or centimeters thick in total, whereby the thermoplastic layer 108 must be even thinner, and a selected masterbatch (e.g., white or a desired selected wavelength resin, optionally also an IR (infrared) resin that may be used, for example, for IR remote control applications) is provided at a desired concentration (e.g., a let-down ratio of about 1%) to establish layer 108 in a plastic resin layer about 2 - 4 mm thick (e.g., 3 mm). Very satisfactory results can be obtained by using this. Generally, in many embodiments within the context of the present invention, the achievable let-down (administration or doping) ratio is actually about 5%, 4%, 3%, 2%, 1%, or less. For example, an industrial grade masterbatch suitable for the purpose is provided by Lifocolor (trademark). The so-called "hidden until illuminated" effect can be achieved for the light source 104 or other features included in the structure 100 by adding, for example, a translucent, e.g., a masterbatch exhibiting a selected color, to the injection molding base resin constituting layer 108.

[0045] Article 124 refers to an overcoat that at least partially covers the light-emitting portion of a light source, and the overcoat layer optionally comprises a light-transmissive material having a refractive index higher than that of the plastic layer.

[0046] Overcoat 124 refers to, for example, an optional encapsulant, glove top, or other conformal coating (such as Illumabond™ or Triggerbond™) for optical shaping or other processing, protection and / or fixation purposes. The material used can be dispensed onto the selected circuit configuration (such as light source 104 or other electronics included in the structure). The material can be, for example, substantially clear (transparent). Alternatively, it can be colored and / or translucent. In some embodiments, certain optical functions or features (such as lenses) may be provided by the encapsulant. The lens can be, for example, a diffusive lens, a Fresnel lens, or, for example, a collimating lens. Additionally or alternatively, off-the-shelf lenses or generally optical components can also be included in the structure, either on the surface or embedded.

[0047] The substrate film 102 and / or further film(s) or generally material layer(s) included in the multilayer structure can include at least one material selected from the group consisting of polymers, thermoplastics, electrical insulating materials, PMMA (polymethyl methacrylate), polycarbonate (PC), flame retardant (FR) PC film, FR700 type PC, copolyesters, copolyester resins, polyimides, copolymers of methyl methacrylate and styrene (MS resin), glass, polyethylene terephthalate (PET), carbon fiber, organic materials, biomaterials, leather, wood, fabrics, cloth, metals, organic natural materials, solid woods, veneers, plywood, barks, tree barks, birch bark, cork, natural leather, natural fibers or cloth materials, naturally cultivated materials, cotton, wool, linen, silk, and any combination thereof.

[0048] Depending on the embodiment of the problem, the substrate film 102 and / or any additional film(s) or layer(s) potentially included in the structure may comprise or be made of an optically substantially transparent or at least translucent material(s), considering wavelengths of interest (e.g., visible light) having a relevant light transmittance of, for example, about 80%, 90%, 95%, or more. This can apply particularly when the substrate film 102 is configured within the structure 100 to effectively transmit or pass the light emitted by the light source 104. However, in some embodiments, the substrate film 102 used can be substantially opaque, black, and / or otherwise dark-colored in order to block (mask function) the incident light from passing through it.

[0049] The thickness of the film 102 and optionally any additional film(s) or layer(s) included in the structure 100 can vary depending on the embodiment. For example, it can be on the order of just a few 10s or 100s of millimeters, or quite thick, on the order of 1 or several millimeters.

[0050] The thickness of the layer 108 can also be selected as appropriate, and a thickness on the order of several millimeters (e.g., about 3 - 5 millimeters) can be applied. In some embodiments, a thickness of just about 2 millimeters or less, potentially on the order of just a few 10s of millimeters, may be sufficient if not optimal, while in some other embodiments, the thickness can likewise be quite thick, for example, at least about 1 cm or more in some places. The thickness can actually vary locally. In addition to accommodating various elements (e.g., electronic or optical elements), the layer 108 may optionally include recesses or internal cavities, for example, for purposes of light guiding, processing, and / or thermal management.

[0051] The film 102, layer 108, and further layers of the structure (e.g., film, coating) can be essentially planar (the width and length are greater than the thickness, e.g., orders of magnitude different). The same generally applies to the entire structure as illustrated in the figures, although other non-planar shapes are also fully feasible.

[0052] Item 104 preferably refers to a light source of optoelectronic type. The light source 104 can be or include a semiconductor, a packaged semiconductor, a chip-on-board semiconductor, a bare chip, an electroluminescent and / or printed type light source, preferably an LED (light emitting diode) or an OLED (organic LED). The light source 104 can be of the upper shoot and lower attachment, or side shoot type. Still, a multi-side shooter or a lower shooter can be utilized according to the characteristics of each specific use case.

[0053] Furthermore, from the perspective of packaging, the light source 104 can optionally be of the flip-chip type. In some embodiments, the light source can include a plurality (two, three, four, or more) of light emitting units (e.g., LEDs) that are packaged or at least grouped together. For example, a multi-color or specifically an RGB LED composed of multiple LED emitters can be provided within a single package.

[0054] The light source 104 is provided (e.g., processed) or, in the case of at least partially off-the-shelf components, optionally (e.g., printed with reference to an OLED), mounted on the substrate film 102, preferably on the first side 102f and its associated surface, which is provided to face the transmissive layer 108 instead of the opposite second side 102s and the surface of the film 102. Further, additional host layer(s) (e.g., film) can be included in the structure to accommodate further elements (e.g., light source or other electronic devices). For mounting, an adhesive (conductive or non-conductive), for example, can generally be applied.

[0055] The light source 104 can be at least partially embedded in the material of layer 108 during overmolding or in preparing the layer 108 thereon by other means.

[0056] The layer 108 can include one or more light output coupling regions 112 on any side of the layer 108 (e.g., the first 108a side or the second 108b side). The light that is first emitted by the light source 104, input-coupled into the layer 108, and propagated within the layer 108 is output-coupled to the surrounding layer(s) and / or the environment. The light source 104 can be positioned as desired in consideration of each output coupling region(s) 112. The source 104 can be positioned close to the region 112 such that the relevant direct optical path is available from the emission surface(s) of the source 104 without reflection. Alternatively, and perhaps more generally, the source 104 is located farther away from the relevant output coupling region(s) (e.g., out of line-of-sight, away from, or near the region to an outer environment) for various reasons, which can include, for example, better hiding or masking the source 104 from external perception by propagating the light emitted by the source 104 within the layer 108 and at adjacent layer or material interfaces over a longer distance and period, or enhancing the uniformity of illumination (e.g., brightness and / or color(s)) on the region(s) 112. FIG. 1 shows only a single light source 104 for clarity. In many embodiments, one source 104 may be sufficient, although not advantageous in some cases. As will be readily understood by those skilled in the art, in the field of illumination of large areas where it may be possible to benefit, for example, from including several sources 114 on the same or different substrates (and using shared or separate transmissive layer(s) 108 and / or reflector design(s) 110), there are numerous embodiments having at least partially connected or separate output coupling region(s) 112 associated with and affecting the positioning and orientation of the light source 104.

[0057] Item 106 refers to a circuit design part in the form of one or more at least electrical conductors or electrical conductor portions (e.g., traces, electrodes, and / or contact pads), which can optionally further act as a heat conductor and can be optionally additionally generated (e.g., screen-printed or printed by other methods). The conductor can be used, for example, for power and data transfer purposes between elements of the structure 100 and / or with external elements. Among other uses, the circuit design part 106 can provide a control signal and / or power from a controller and a power circuit (s) to the light source 104 respectively. The circuit design part 106 can be connected to an external device, for example, via an outer surface or an edge including the wiring or connector of the structure 100. Additionally or alternatively, wireless connectivity can be applied, among other options, for example, based on electromagnetic coupling or particularly inductive coupling. The circuit design part (s) 106 can be disposed on or inside the base film 102 and / or other host (ing) elements (e.g., material layers of the entire multilayer structure). Inside the structure, there can be, for example, several local or partial circuit design parts 106 on different layers or on its host, which can be selectively connected together at least operably even if not physically, and can establish a larger circuit design part spanning several elements (e.g., layers of the structure). Some elements (e.g., conductors (e.g., traces)) can be physically positioned so as to be distributed or shared between two or more layers of the structure (e.g., a first part existing on / inside one layer and a second part on / inside another layer). Thus, such an element can be regarded as part of several local circuit design parts or a larger circuit design part (e.g., on different layers).

[0058] The light source 104 can be emissive as shown by the dotted lines 104a (top shooting), 104b (side shooting) extending from the source 104 to the transmissive layer 108.

[0059] Item 110 and sub-items 110a, 110b, 110c (see Figure 2) refer to the reflector design portion, which can also be of a single-component or multi-component (multi-part) structure. Two or more parts of the multi-component structure solution do not need to be physically directly connected as they can be present, for example, on opposite sides 108a, 108b of layer 108 or be separated by distance in other ways. However, any of the components or parts can include one or more material layers, for example, as stacked components thereof.

[0060] Accordingly, the reflector design portion 110 includes at least one material layer. The reflector design portion 110 is configured to optionally reflect mainly specularly the light initially emitted by at least one light source 104 and incident on the reflector design portion 110.

[0061] One or more parts of the reflector design portion 110, or the entire design portion 100, can be located on the side facing the first side 102f of the substrate film 102 that receives the light source 104 (see the reflector / reflector part 110a for illustration), opposite (see the reflector / reflector part 110b for illustration), and / or across it (see especially the reflector / reflector part 110c for illustration), on the side of the plastic layer.

[0062] In some embodiments, at least a portion of conductor 106a that establishes circuit design section 106, as illustrated by the scenario depicted in 150 (sub-sketch of FIG. 1), may be configured to be located external to plastic layer 108 that transmits light, reflector design section 110, and any possible additional intermediate layer(s) (e.g., layer 114), such that, for example, instead of facing the side of plastic layer 108 that transmits light, the side of reflector design section 110 that faces away from light-transmitting (light-permeable) plastic layer 108 and optionally the surface are positioned. Generally, at least a portion of the conductor, even when conductor 106a is configured to transfer data or energy, for example, optionally at least essentially or partially, between electronic devices (e.g., light source 104) that are present within the volume, may be located away from layer 108 and the volume spanning the intermediate space to reflector design section 110.

[0063] Similarly, at least a portion of substrate film 102 itself may be positioned to be located on the side opposite the side that actually faces and potentially directly attaches to and contacts light-permeable layer 108 of at least a portion of reflector design section 110e. Thus, the stack order of reflector design section 110e and substrate film 102 may be at least locally reversed, for example, from the stack order of the main drawing provided in FIG. 1. For example, one or more conductors of design section 106 may be provided on substrate film 102, parallel to its surface (e.g., near or under an electronic component (e.g., light source 104)), which is also depicted in the sketch. For example, instead of directly generating layer 108 on substrate film 102 (and potentially on one or more conductors of circuit design section 106 and / or light source 104 already provided on film 102) by molding, layer 108 may be pre-manufactured, optionally with features 103 (e.g., holes for accommodating light sources and / or at least a portion of reflector design section 110e) before attachment to substrate film 102 as indicated by the two arrow symbols in the figure. For that purpose, suitable lamination techniques based on, for example, adhesives, heat, and / or pressure may be utilized.

[0064] Thus, when the conductor is not mostly at a distance from the transmissive layer 108, it is at least partially or essentially fully positioned and does not interfere with, or at least minimally interferes with, the optical path of the light emitted by the light source 104, such that the light propagates within the transmissive layer 108 and reaches the reflector design portion 110 at least occasionally and reflects therefrom, so that the optical efficiency of the arrangement and indirectly also the electrical efficiency can be enhanced. Otherwise, the conductor may cause excessive undesirable phenomena to the incident light, including, for example, diffusion and absorption. However, in certain embodiments, the effect of the conductor on the incident light can be utilized for useful purposes, such as, additionally or alternatively, optical effects (such as diffusion, attenuation, or shadowing).

[0065] In a preferred embodiment, the reflector design portion 110 or at least a part thereof is typically configured to at least roughly reflect the previously propagated incident light towards the layer 108, or back to that layer, typically inside the (transmissive) layer 108, in order to prevent undesirable optical output coupling or light leakage from the structure 100. In some embodiments, the reflector design portion 110 may comprise at least a part that is configured to direct the incident light in an alternative direction (e.g., outside the layer 108 or the entire structure 100).

[0066] Furthermore, the reflector design portion 110 can be configured on or within the layer 108 to reflect and direct the light emitted by the light source 104 and incident on the reflector design portion 110 to propagate towards the output coupling regions 112, 112a, 112b, 112c. In some embodiments, which will also be described below, the reflector design portion 110 can be configured to direct the incident light towards the surface normal of the layer 108 in order to output-couple light from at least the layer 108 or the entire structure.

[0067] Indeed, referring, for example, to the sketches of FIGS. 2 and 3, the reflector design portion 110 can be configured at least in relation to the light input-coupled from the light source 104.

[0068] The reflector design portion 110 or at least a part thereof may be located (110a), 110b, 110c on the direct optical emission path from the light source 104. Further, the reflector design portion 110 may be located beside and / or below the light source 104, or may include a portion 110b on and / or opposite the light source 104 (e.g., on the opposite side 108a of the layer 108 with respect to the light source 104) such that the design portion 110 receives and reflects at least a part of the light emitted by the light source 104.

[0069] As illustrated, by way of example only, in 300 of FIG. 3, the reflector design portion or a part thereof 110b may be configured to be input-coupled from the light source 104 into the layer 108 and to reflect the light incident on the reflector design portion 110 to further align with the side surface of the layer 108 that substantially traverses the surface normal of the layer 108.

[0070] Generally, a part of the reflector design portions 110, 110a, 110b, 110c may be at least partially embedded in the layer 108 and may be located on the surfaces 108a, 108b thereof.

[0071] And, as well illustrated, by way of example, in 200 of FIG. 2, the light source 104 may be located between at least a part of the reflector design portion 110c that is preferably aligned substantially perpendicular to the light output coupling region and the light output coupling region 112. Then, the light source 104 may be aligned to face at least partially towards the reflector design portion 110c with respect to its primary emission direction. For example, a light source, e.g., a side-emitting LED or other source, may be aligned to point, e.g., about 180 degrees away from the direction of the output coupling regions 112, 112a, 112b, 112c (shortest path).

[0072] Thus, in a typical scenario of some light sources being utilized, the distance between the light source 104, or multiple light sources 104, and the associated output coupling regions 112, 112a, 112b, 112c is kept short and can be reduced from more conventional solutions because each optical distance defined by the path that the light emitted by the light source(s) 104 actually takes before the output coupling 112 is approximately doubled the distance D illustrated in the figure, i.e., the distance between the reflector design part 110c and each associated light source 104. As will be understood by those skilled in the art, this translates to a smaller applicable multilayer structure and / or a larger output coupling region 112, 112a, 112b, 112c that can be obtained with suitable light mixing characteristics, depending on the set of preferences for the application.

[0073] The reflectivity of the reflector design part 110 is selected to be at least a portion of the wavelengths emitted by the light source(s) 104 and, optionally, in light of essentially all visible wavelengths, preferably at least locally about 75%, more preferably at least about 90%, and most preferably at least about 95%.

[0074] For example, to achieve sufficient reflectivity, the reflector design part 110 or some other optical functional elements included in the structure preferably include at least locally at least one element selected from the group consisting of: - Electrically conductive materials (e.g., aluminum, silver, gold, zinc, copper, or beryllium), - Metals, optionally metal particles, and further optionally provided on top of or within a substrate film or a further film or layer included in the structure, metals, - A plurality of stacked and superimposed material layers of at least two mutually different refractive indices that optionally define a Bragg mirror, - Thin film coatings, optionally PVD (physical vapor deposition) coatings, and -(Reflective) preferably printable inks or paints.

[0075] Thus, by utilizing a conductive material (e.g., metal) within one or more layers of the reflector design section 110, the so-called skin depth of the reflector design section 110 and the underlying structure as a whole are kept small, thereby increasing the reflection efficiency. The conductive material and metal can be provided, for example, in the form of a film, paint, ink, or an extrusion (e.g., metal particles in a host material (e.g., plastic)) process. In principle, any practical metallization procedure can be applied to provide the metal(s).

[0076] Alternatively or additionally, a plurality of stacked layers (potentially dozens or hundreds of layers) can be applied to establish a connected and effective, preferably integral, reflective structure such as a Bragg mirror. In such a structure, layers of different refractive indices can be alternated in sequence. For example, two materials of different refractive indices can be configured to alternate within a multilayer reflector stack that constitutes at least a portion of the reflector design section 110. At each interface between two material layers, a Fresnel reflection is advantageously created. When the optical path length difference between subsequent layers is half a wavelength (i.e., each layer is a quarter-wavelength thick), the reflections interfere constructively (zero / 360-degree phase shift between the reflections). For example, plastic polymer materials can be utilized in the multilayer reflector stack, such as, for example, PMMA and PC or PS. The stacked integral multilayer elements can also, in some embodiments, include a substrate film 102 and / or other film(s), or generally layer(s) or feature(s) (e.g., item 114, 116), which will be described in more detail below.

[0077] The stack included in the reflector design section 110 can optionally be realized as an off-the-shelf multilayer film. Alternatively, some, optionally stacked, material layers of the reflector design section 110 can be generated by a selected coating technique (e.g., PVD or electroplating on plastic) on a substrate (e.g., substrate film 102). Alternatively or additionally, for example, a (multiple) coextrusion process can be applied.

[0078] Item 114 refers briefly to at least one further one which is optionally stacked and further optionally in contact with the reflector design part 110 and which is optionally additionally produced, for example, by printing a material layer. The at least one further material layer 114 preferably has a lower refractive index than layer 108. For example, when layer 108 is of PC, layer 114 can comprise PMMA.

[0079] The at least one further material layer 114 and layer 108 are optionally connected and optionally also physically close and redirect at least a part of the light emitted by the light source, propagated in the plastic layer 108 and incident on the at least one further material layer 114, by total internal reflection (TIR) at their interface, towards and back into this plastic layer. Generally and for example, when the reflector design part 110 is stacked and arranged, for example, behind the interface of layers 108, 114 on the optical path, the reflector design part 110 cooperates effectively with the interface and reflects, for example, the remaining light passing through the interface, at an angle lower than the relevant critical angle, and can thus be incident behind the reflector design part 110.

[0080] Thus, at least one layer or other part of the reflector design part 110, the layer of the at least one further material layer 114, and layer 108 can be at least locally superposed such that the material of the layer of the at least one further material layer 114 is stacked between the material of the reflector design part 110 and layer 108 with respect to those materials.

[0081] Generally, at least parts of the reflector design parts 110, 110a, 110b, 110c and the at least one further material layer 114 can be mutually present on the same side, the opposite side, or both / plural sides 108a, 108b of the layer 108.

[0082] At least one additional material layer 114 may optionally comprise, or consist of, for example, an optically clear adhesive (OCA) or a primer.

[0083] In general, for example, within layer 114 or elsewhere, for example, using patterned selectively (more) low refractive index materials, light propagation within the structure can be effectively controlled both from a technical and cost perspective. For example, in a large structure having one or more light sources 104, it can be advantageous to selectively create light guiding and light guiding enhancement (e.g., reflection (boundary)) structures. Light guiding structures such as items 108, 110, 114, 116 can be constructed, for example, for each sector having different optical properties and, for example, lengths or generally dimensions.

[0084] In some embodiments, an integrated multilayer structure such as multilayer film 102a can be included in structure 100 as a prefabricated or in-situ fabricated element.

[0085] Multilayer film 102a can include, for example, a plurality of, for example, two stacked, attached, optionally coextruded layers, one of which can be, among other options, a substrate film 102 or similar layer for receiving, for example, light source 104, as well as circuit design section 106, and potential additional electronics or other elements, or can establish it, but at least one other layer can be at least one layer of item 114 and / or reflector design sections 110, 110a (which can itself be a multilayer material stack as discussed earlier herein).

[0086] In some embodiments, intermediate layer 116 can be provided within the structure, for example, between layer 108 and (if present) a layer of at least one additional material layer 114, and / or between layer 108 and reflector design sections 110, 110b on the first side 108a of layer 108 and layer 108.

[0087] For example, the intermediate layer 116 embodied as a film can also act as a substrate (surface) for various elements (such as electronic components including a light source, for example, light). The intermediate layer 116 can optionally include the same light-transmissive material as layer 108 or can have at least a similar refractive index thereto. The previous considerations provided herein with respect to the substrate film 102 can generally be applied to the intermediate layer 116, as will be understood by those skilled in the art.

[0088] The intermediate layer 116 and at least one of the at least one further material layer 114 and / or at least one layer of the reflector design portions 110, 110b can further be a constituent of a multilayer structure (such as a multilayer film 116a), optionally a coextruded multilayer film.

[0089] Articles 120, 122 optionally refer to one or more elements (such as material layers) that are either on the outer surface of the structure on one or both sides 108a, 108b of layer 108 (preferably within one or two material layers) or at least near thereto (preferably within one or two material layers). They 120, 122 can include films, coatings, prints, plastic materials, natural materials (such as leather as listed in connection with the previous applicable substrate films / film materials herein). Articles 120, 122 can receive other features (such as electronic components) or layers and can thus also be regarded as substrates (plural if applicable) depending on the embodiment. Preferably, articles 120, 122 are at least somewhat translucent and optionally include (through) holes filled (with at least a translucent material) or cover only limited areas (plural if applicable) to enable light output coupling from the structure. For example, different lamination, printing, coating, molding, or extrusion methods can be utilized to provide either of articles 120, 122.

[0090] Article 118 refers to one or more output coupling elements that the structure can include, for example, originally separate or not monolithic but integral with the remaining elements (such as the reflector design portion 110 or various (other) material layers).

[0091] For example, the reflector design section 110 (e.g., a layer or other part of the reflector design section), or further elements or specifically layers of the structure on which the light emitted by the source 104 is incident, may receive, or be, or define, a locally processed, preferably mechanically, chemically or electrically processed, optionally deformed (e.g., stretched) part (e.g., a material stack part or a material layer part where locally two or more, optionally all layers of the stack are deformed), and the respective reflection characteristics for light redirection and output coupling are changed (e.g., changed implies that the reflection is reduced), either via the layer 108 or more directly without passing through the layer 108 (any further). As a practical example, such an output coupling element 118 can be provided on one side of the layer 108, e.g., side 108b, to the reflector design section 110 (one or more associated material layers), such that at least a portion of the light incident on the element 118 is output coupled either via the surface 108a of the layer 108 after passing through the layer 108 or potentially via the bottom surface of the structure (as shown in the figure) without entering the layer 108 any further.

[0092] As previously mentioned herein, instead of, or in addition to, the reflector design section 110, other elements of the structure (e.g., the layer 108) may locally receive or define surface features or surface patterns that form at least a portion of the output coupling element 118, and optionally include roughened or otherwise deformed regions for output coupling the light incident therein.

[0093] Any of the elements 118 may, for example, be scattered / diffused or collimated.

[0094] In the cross-sectional sketch of FIG. 5, a plurality of output coupling elements 118 are illustrated at 500, preferably comprising some preferably printed, optionally scattering elements on the layer 108 with spatially varying incident densities and / or preferably dimensions including at least thickness.

[0095] Thus, in the illustrated and other usage scenarios and embodiments, the incident density, thickness, and / or one or more other dimensions of the output coupling element 118 are configured to increase with the distance from the light source(s) 104 to respectively enhance the output coupling performance with distance (e.g., at least relatively, as contrasted with the output coupling performance of closer elements 118), and one or more of such output coupling elements may optionally include a fluorescent, phosphorescent, thermochromic, or photochromic material.

[0096] For completeness and to facilitate understanding of the different configurations that embodiments of the present invention may adopt in each application, FIG. 13 illustrates an alternative arrangement of the material layers included in the structure at 1300. Specifically, at least a portion of the reflector design portion 110 (e.g., one or more layers of that reflector design portion), if not as an entire design portion, may be at least locally adjacent to layer 108 and / or stacked between layer 108 and, for example, film 102. However, in the sketch of FIG. 1, for example, the reflector design portion 110 is illustrated behind film 102 from the perspective of layer 108, i.e., near the outer or outer surface of the structure.

[0097] However, in some embodiments, at least a portion of the reflector design portion 110 is positioned near the substrate film 102 such that light input couples from the light source 104 into the substrate film 102 and subsequently propagates within the substrate film 102 by reflection (mirror, TIR, etc. depending on adjacent elements or specifically layers) and impinges on the output coupling region 112 or element 118, enabling the light to proceed outside the substrate film 102 and optionally through the plastic layer 108 into either a further layer(s) and / or the environment. The associated output coupling region 112 or element 118 may also, in this scenario, comprise or consist of, for example, a deformed substrate or generally a material portion, coating, or printed portion.

[0098] FIG. 4 illustrates, via a cross-sectional sketch, an embodiment 400 in which, still of course, depending on the light transmission characteristics of subsequent upper layer(s) and element(s) in the optical path, through the reflector design portion 110, optionally, several holes 410 are configured within the reflector design portion 110 to enable or facilitate light output coupling out of the entire structure. Thus, the figure also depicts potential configurations of several additional layers within the optical path for light output coupling from the structure, and at least some holes may also be provided in one or more of the additional layers or elements 412, 414, 416, and these holes may be configured to stack with the holes of other layers (e.g., holes 410 within the reflector design portion 110) or be laterally aligned. As shown in the figure for illustrative purposes, on the left side, the holes 410 penetrate all the layers above layer 108, while the holes 410 on the right side are present only in items 110, 412.

[0099] One or more holes 410 in any of items 110, 412, 414, 416 may be left unfilled (thus, for example, may accommodate air during the manufacturing process of a multilayer structure) or may be filled with a suitable material (e.g., an optically at least translucent material if not transparent, optionally, for example, a glass or plastic (e.g., thermoplastic) material). The filling material may, for example, be optically diffusive.

[0100] The configuration of the holes 410 within the reflector design portion 110 and optionally additional layers 412, 414, 416 may be performed regularly or irregularly with respect to selected characteristics (e.g., incident density, shape, or size (e.g., diameter)). The incident density and / or the size of the holes preferably increase with the distance from the light source 104, for example, when the distance from the source-induced loss is to be compensated with the light output-coupled for more uniform illumination. At 420, a top / plan view of the reflector design portion 110 and its potential additional layer(s) of the reflector design portion is depicted to visualize how the configuration of the associated holes 410 may be adapted spatially, for example, in response to the distance from the source(s) 104.

[0101] Any of the apertures 410 can be created in any of the articles 110, 412, 414, 416, either through a perforation or, in the case of apertures created in other ways, by subtractive removal of material from the article. Additionally, for example, referring to molding and printing techniques, additional processes can be applied to generate a layer having several apertures. The apertures can have, for example, a diameter of 50 to 200 μm and / or a round shape, although other sizes and shapes are also technically feasible.

[0102] The aperture 410 can be a through-hole, but in any case, as will be readily understood by those skilled in the art, the remaining material at the location of the aperture, which may need to adhere to a somewhat lower material thickness locally, for example, when implementing a translucent transmissive layer, the use of one or more non-through-holes is also feasible.

[0103] The aperture or apertures 410 can also be generally considered in many usage scenarios, for example, in connection with the description of FIG. 14 and other parts of this specification, as an embodiment of the output coupling element 118, or at least a part of an embodiment. Thus, instead of adding an aperture, other features that break / deform a target element (e.g., a target layer) or otherwise locally modify it can still optionally be utilized with the necessary modifications made in accordance with the principles described above for apertures.

[0104] Article 412 preferably refers to an opaque masking element or layer, which can be printed (e.g., a white print), prepared jointly (e.g., co-extruded), coated, or otherwise prepared or laminated (e.g., a film is laminated optionally using pressure, an adhesive, etc.) on, for example, other elements or layers (e.g., the reflector design 110).

[0105] Item 414 refers to a diffuser element or layer, which can be printed, for example, on another element or layer (such as the reflector design 110), prepared jointly (such as co-extruded), coated, or prepared or laminated in other ways (for example, a film can be laminated optionally using pressure, adhesives, etc.).

[0106] Item 416 refers to at least one element or layer that is not transparent and is at least locally translucent, which can be printed, for example, on another element or layer (such as the reflector design 110), prepared jointly (such as co-extruded), coated, or prepared or laminated in other ways (for example, a film can be laminated optionally using pressure, adhesives, etc.).

[0107] In addition to its aesthetic or look-and-feel type role, item 416 can have a protective function and / or an indicative function (which can include graphical indicators (such as symbols) optionally generated by printing).

[0108] As will be understood by those skilled in the art, any of the aforementioned items 412, 414, 416 can be provided in the structure as a ready-made element, prepared on-site thereon, or installed together with one or more of the other added items 412, 414, 416. Items 412, 414, and / or 416 can further establish at least a portion of the item 120 or 122 discussed earlier.

[0109] FIG. 6 illustrates at 600 an embodiment incorporating an embedded circuit board 602 for receiving a light source 104 and potentially further electronics, and a reflector design 110 including a parabolic reflector surface 610. In some embodiments, the circuit board 602 can be omitted and the light source 104 is provided on the substrate film 102 directly or via some other intermediate entity such as a material layer.

[0110] By providing at least the light source 104 on the circuit board 602, a lighting module including at least these two is conveniently provided on the base film 102 and attached, for example, using a conductive and / or non-conductive adhesive(s), and preferably electrically connected to the circuit design part 106 thereon, for example, using a conductive ink or adhesive. The circuit configuration on the board 602 includes at least locally a local circuit design part or sub-design part on the board 602 in a desired pattern, for example, a conductive trace or pad for connecting components (e.g., the light source(s) 104) to other components or elements (e.g., control or communication circuits).

[0111] By utilizing the circuit board 602, the thermal management of the remaining structure can be facilitated, and 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, and even much larger. Optionally, multiple light sources with similar or different characteristics (wavelength / color, power, emission direction, beam width, technology, etc.) from each other can be on the board 602.

[0112] The circuit board 602 can 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 rounded or essentially circular sheet or film, an FR4-based circuit board, a metal core circuit board, a plastic substrate, a molded product such as an injection-molded plastic substrate, a metal substrate such as a sheet metal substrate optionally provided with at least a selectively provided electrical insulation layer, and a ceramic circuit board.

[0113] In various embodiments, circuit board 602 or, for example, substrate film 102 or some other substrate layer within a structure may receive various electrical and / or other elements (e.g., series resistors, thermistors, white solder masks, traces, antennas, sensors, electrodes (e.g., capacitive sensing electrodes), contact pads, integrated circuits, controllers, processors, memories, transceivers, driver circuits, optionally optically clear glove tops, or other conformal coatings, as well as vias (e.g., electrical vias, fluid vias, and / or thermal vias)).

[0114] Generally, circuit board 602 may be planar and may preferably be round, though not essentially circular or elliptical by its general shape. The dimensions, shape, and thickness of the circuit may vary depending on the use case. Thus, for example, a rectangular shape is also possible. The thickness may be, for example, a fraction or portion of a millimeter (e.g., about 0.2 to about 0.6 mm), a millimeter, several millimeters, or more. However, the diameter may be, among other options, several millimeters, about 1 centimeter, or several centimeters. Castellations may be provided at the edges for convenient edge connections.

[0115] For example, if the circuit board 602 itself is not made of a translucent or transparent material, at least some holes 603 may be provided in the circuit board 602 to allow the light emitted by the light source(s) 104 and reflected from the parabolic reflector 610 to pass conveniently towards the environment and, for example, potential user(s) 113 in that environment without unwanted problems (such as shadows in the resulting light distribution). Of course, the concept of using a circuit board that preferably has holes provided to accommodate the light source 104 and / or other electronic device(s) or element(s) is also achievable in embodiments without a parabolic reflector 610. The holes 603 can be filled with a light-transmissive, non-transparent, at least translucent material, for example, by the material of that layer when forming layer 108 by molding. For example, this material can optionally further secure the substrate 602. In the scenario shown, of course, the base film 102 and potential layer(s) or other element(s) thereon are preferably at least somewhat at least translucent so as to allow light transmission.

[0116] In either case, the reflector design portion 110 preferably defines, at least locally, a collimating reflector surface 610, optionally an essentially parabolic reflector, on the side 108a of the layer 108 that faces the side 108b of the substrate film 102 that receives the light source(s) 104. The surface 610 or the reflector design portion 110 can generally be obtained by a selected coating method applied to the receiving surface, as discussed elsewhere in this specification, for example. The parabolic receiving protrusions or "bump" surface shape on the surface 108a within the layer 108 can be obtained during the molding and / or printing of the layer 108 by utilizing a suitable mold shape or later, for example, by a selected subtractive or additive process. The opposing surface 108b can be kept smooth, which can be beneficial in applications that require, for example, a flat film 102 surface or, for example, an overall outer surface facing the (use) environment of the structure. The associated motivations can vary, but can include, for example, obtaining or requiring surface treatment, functionality (e.g., touch sensing), or aesthetics that benefit from or require a substantially flat target.

[0117] FIG. 7 illustrates at 700 another potential embodiment with a parabolic reflector surface and shape. The light source(s) 104 is (are) then offset from the optical axis or axis of symmetry of the reflector shape and thus is (are) located laterally of the associated light aperture, and again, for example, unwanted shadowing can be avoided or at least reduced on the illuminated surface on the film 102. Optionally, the circuit board(s) 602 can also be utilized in this scenario (not illustrated).

[0118] FIG. 8 illustrates, at 800, an embodiment of an illumination assembly including a plurality of mutually different multilayer structures generally discussed herein. Two or more of such structures 801a, 801b may also be prepared, stacked, and preferably attached together (adhesives, mechanical fixing elements, or other bonding methods may be used herein) to establish a functional assembly. Alternatively, the assembly 800 may otherwise be constructed, for example, layer by layer. The assembly 800 may be configured to output couple light from each of the structures 801a, 801b to one or more surfaces of the assembly and / or onto illuminated output coupling elements 812a, 812b within and / or on the surface of the assembly via output coupling regions 112a, 112b that are optionally at least partially non-overlapping. The output coupling regions 112a, 112b may be associated with characterizing a visual (e.g., printed or mask-based graphic) provided in any of the illuminated surface layer(s) 120, whereby, when one or more of the structures 801a, 801b includes a number of independently controllable sources 104, independently controlling the light output from the structures 801a, 801b and optionally also from the further included light sources 104 may be utilized to selectively illuminate the visual and generally make them visible for external perception. Thus, functionally complex illuminated / lighting structures may be constructed from combinable structural assemblies that are mutually different or similar but simpler in terms of structure, dimensions, and / or included features or associated functionality.

[0119] FIG. 9 illustrates, at 900 (cross-sectional view, see cutting line A-A) and 901 (top / planar extraction view), embodiments in which a writing or lighting module is included in a structure and includes at least one light source 104 (six in the example shown) on a circuit board 602 (on a substrate film 102) and is further potentially receptive of additional electronics or optics.

[0120] The circuit board 602 may further receive one or more optical elements (e.g., light guides 908) that optionally cover the one or more light sources 104 and include a light transmissive (transparent or at least translucent) material (e.g., a thermoplastic material(s)) discussed elsewhere herein. However, preferably, the wall structure 902 that is optically transmissive and optionally includes a clear material at least in places is advantageously disposed around the circuit board 602. Further, there may preferably be an air gap or filler 909 (again, preferably including a transparent or at least translucent material) between the wall structure 902 and the light guide 908. The circuit board 602 may further include some optionally filled (semi-transparent / transparent filler) holes 603 to allow light transmission through the holes, as detailed earlier herein.

[0121] FIG. 11 illustrates, at 1100, an embodiment in which the structure includes a plurality of light sources 104 and other circuitry 105 (e.g., associated control circuit configurations).

[0122] The control circuit configuration 105 (e.g., a driver circuit, a controller chip (e.g., a microcontroller), a microprocessor, (other) integrated circuits, etc.) may optionally be at least partially integrated with any of the light sources 104 while still being electrically connected thereto, for example, via a circuit design portion 106, instead of being separated or in addition thereto. Preferably, the circuit configuration 105 is configured to dynamically and / or independently adjust, for example, the intensity of emission and / or other characteristics (e.g., color distribution when applicable) of each of at least two of the light sources 104. However, also, linkage control may be enabled, additionally or alternatively, for two or more of the light sources 104. However, the circuit configuration 105 may at least be functionally connected to an external circuit configuration via wiring and connectors(s), e.g., via power data and / or power transmission.

[0123] In the case of a light source 104 such as an LED, for example, PWM (pulse width modulation) or current control can be utilized for that purpose. The control circuit configuration 105 can be included in the structure even when only a single light source 104 is present.

[0124] FIG. 12 illustrates an embodiment including a bent portion in layer 108 (at 1200 via a cross-sectional top view, at 1202 a skeletal view in the A-A direction, and at 1204 a cross-sectional view along B-B).

[0125] At least layer 108 actually defines a bent portion having a bending angle of optionally at least about 10 degrees, potentially at least about 30 degrees or 45 degrees, and at least a portion of the reflector design portion 110 is essentially located on layer 108 at its outer periphery and / or inner periphery. Accordingly, the reflective portions 110a, 110b, 110c, 110d are illustrated in the figure accordingly.

[0126] By utilizing the reflector design portion 110, bent portions and other similar, more complex shapes can be implemented in layer 108 and the general structure essentially without loss of optical efficiency. In addition to the reflector design portion 110, a TIR-type interface and associated activating element or layer (e.g., layer 114) can be included in the structure to maximize light guiding efficiency as will be discussed more thoroughly elsewhere in this specification.

[0127] FIG. 14 further illustrates at 1400 different options and configurations for light output coupling in connection with various embodiments of the present invention, some of which are also contemplated in connection with the descriptions of the other figures attached hereto.

[0128] Accordingly, some output coupling elements 118 such as specific shapes and / or material layers for controlling or enhancing output coupling can be provided, for example, on the surface of layer 108 as if embedded, or subsequent to layer 108 (from the perspective of the optical path), in the optical path from the light source 104 out of the structure.

[0129] Item 1412 refers to a type of output coupling element 118 that includes features for enhancing optical output coupling, for example, being part of the reflector design section 110 or comprising material layers and / or other output coupling features adjacent thereto within the structure.

[0130] Thus, the output coupling element 118 including 1412 comprises optionally, a locally concave or convex surface (e.g., the surface of layer 108) that defines one or more, for example, prism-shaped recesses or protrusion shapes 1418, and an element, or specifically, a layer 1412a of a transparent or optically at least translucent material that has a refractive index lower than that of the optically subsequent adjacent material, such as air, and / or a perforated, apertured, or otherwise locally thinned or through-cut layer of an opaque material, and an element, or specifically, a layer 1412b having holes (without filler or with a translucent / transparent filler) in a carrier material (which may be opaque), and an element, or specifically, an alternating layer 1412c of a higher refractive index material 1414 and a lower refractive index material 1416, and an adhesive or adhesion promoting primer, preferably of a type that is substantially optically transparent or at least translucent (which can act as a cladding material).

[0131] FIG. 15 illustrates, in addition to lighting, an embodiment 1500 of a multilayer structure (or an assembly of structures) that further incorporates complementary functionality (e.g., touch or gesture sensing (optionally non-contact)). The complementary functionality can be provided, for example, by an additional layer and other elements disposed on the multilayer structure that includes the light source(s) 104 and further optical features, either as an integral structure or layer by layer.

[0132] For example, a diffuser element 414 (e.g., a film or coating) can be provided.

[0133] Preferably, at least a translucent or substantially transparent, substantially planar electrode 418 may be provided, and optionally, may be printed on the diffuser 414 or other adjacent element or layer, such as 416b. The electrode 418 may be electrically or electromagnetically connected to other circuit components 105, such as drive or sensing circuit configurations, positioned within and / or external to the structure. For that purpose, electrical wiring or wireless connectivity may be applied.

[0134] As previously mentioned herein, item 416 refers to at least one element or layer that is non-transparent, or at least locally translucent, which may be printed on, prepared jointly (e.g., co-extruded), coated, or otherwise prepared or laminated on other elements or layers (e.g., a reflector design 110). For example, item 416 may thereby include, for example, a printed graphic 416a that is optionally laterally adjacent to the electrode 418, and / or an optionally translucent, non-transparent type of protective outer surface element 416b, which still preferably allows for an externally perceivable backlight (i.e., not completely opaque). Item 416 may include plastics, metals or woods, leather, or other biomaterials, inks, fabrics, etc. (perforated, thinned, or otherwise processed, configured, or selected to allow for at least local translucency / transparency).

[0135] FIG. 10 shows at 1000 a flow diagram of an embodiment of a method for manufacturing an integrated optical functional multi-layer structure according to the present invention. Applicable manufacturing processes and related characteristics regarding the possible components and materials of various embodiments of the structure have already been discussed earlier herein, and these discussions will not be unnecessarily repeated herein to clarify the overall, already long-winded description of the method. However, one skilled in the art can return to the previous paragraph to find valuable details regarding applicable manufacturing methods and considerations, but will understand the fact that the same also applies in the reverse direction regarding the structural or functional details potentially included in the multi-layer structure.

[0136] At the start of a method for manufacturing a multi-layer structure, a startup stage 1002 can be executed. During startup, necessary preparatory tasks (e.g., selection, acquisition, calibration, and other configuration tasks of materials, components, and tools) can occur. Special attention must be paid to the individual elements and material selection working together to withstand the selected manufacturing and installation processes, which, of course, are preferably pre-checked based on, for example, the specifications of the manufacturing process and the data sheets of the components, or by examining and testing in detail the manufactured prototypes. Thus, in particular, the equipment used (e.g., equipment providing molding, IMD (in-mold decoration), lamination, connection, (thermal) forming, electronic device assembly, cutting, perforation, printing, and / or measurement (e.g., desired optical measurement)) can be brought up to an operating state at this stage.

[0137] In 1004, for example, obtain at least one, preferably flexible, substrate film of plastic or other material for housing a light source(s) and potentially other electronic devices. The substrate film can initially be substantially planar or can be curved, for example. The substrate film can be at least mainly of an electrically substantially insulating material(s). Off-the-shelf elements (e.g., rolls or sheets of plastic film) can be obtained for use as the substrate material. In some embodiments, the substrate film itself can initially be produced in-house by shaping from a selected starting material(s) using a mold or shaping device or other method. Optionally, the substrate film can be further processed at this stage. For example, holes, notches, indentations, cutouts, etc. can be provided.

[0138] Article 1014 generally refers to the provision of a reflector design part. As will be understood by those skilled in the art based on the prior intentions of this specification, the reflector design part or a part(s) thereof can be provided in different method steps of the structure or by on-site manufacture, depending not only on the constitution of the reflector design part itself but also on other elements within the structure and their constitutions. However, since the reflector design part or a part thereof can be provided to be immediately integrated with further elements (e.g., a film or generally a material layer), in some embodiments, Article 1014 can be integrated with other articles. For example, a multi-layer type of combined element for mounting a substrate and a reflector structure(s) or layer(s) for an electronic device can already be obtained in 1004. In some embodiments, at least a part of the reflector design part can be manufactured or at least attached to a light-transmissive plastic layer (or an assembly including a transmissive layer and potentially further layer(s)), which itself can be of a pre-fabricated or separately fabricated type, for example, instead of being formed directly on-site on a substrate film. When providing a pre-fabricated plastic layer on the substrate film, the plastic layer can already include at least a part of the reflector design part configured thereon (e.g., refer to Article 110e at 150 in FIG. 1 for illustration).

[0139] Thus, the curved arrows, as non-exhaustive examples, indicate that, depending on the particular embodiment of the problem, the order of the indicated method items may be reversed, and / or the items may be integrated or further divided.

[0140] The reflector design and associated material layer(s) can generally be provided, for example, by printing, coating, laminating, or molding. Further, the process can include the formation of various features (e.g., holes in the reflector material) and potentially filling them with other materials, or providing output coupling elements as discussed in more detail earlier herein. The reflector design can include, for example, optionally, one or more material layers comprising a stack of material layers and / or layers of electrically conductive material and / or metallic material. Further, the reflector design (e.g., its layer(s)) can include or be provided with additional elements (e.g., openings (holes)). The reflector design is optionally and in the most common use cases configured to reflect light emitted by at least one light source included in the structure being manufactured and incident on the reflector design, optionally mainly specularly, towards the plastic layer 108 provided at item 1012.

[0141] At least a portion of the reflector design (e.g., one or more layers) can be provided on a substrate film(s) prior to the provision of the plastic layer. See item 1014A. Alternatively or additionally, at least a portion of the reflector design can be provided after or when a plastic layer is disposed on or between a substrate film and another film, potentially a further substrate film existing on the other side of the established intermediate plastic layer 108. See item 1014B.

[0142] However, the two one-way dotted arrows shown further indicate options for each additional or alternative process for providing the reflector design 1014, essentially between items 1008 and 1010, and / or between items 1010 and 1012, or in relation to any of the three aforementioned items.

[0143] In 1006, for example, several electrically conductive and / or optionally thermally conductive elements that define various conductor lines (traces), sensing elements (e.g., electrodes), and / or contact areas (e.g., pads) to construct a circuit design section are provided on one or more of the substrate film(s), preferably by one or more additional techniques such as printed electronics technology or 3D printing. Thus, the circuit design section can include several circuits or circuit sub-design sections on different layers of the overall structure and is optionally connected, for example, via the edges of the structure or via conductive wiring around the edges. For example, screen, inkjet, flexographic, gravure, or offset lithographic printing can be applied by a suitable printing device or a device for generating at least a portion of the circuit design section. In some cases, subtractive or semi-additive processes can be utilized. For example, further actions to modify the substrate film(s) that involve printing or generally providing graphics, visual indicators, optical elements (e.g., masks or output coupling elements), holes / fills, etc. can occur here, for example, if not performed at 1004.

[0144] In various embodiments, the electrically conductive and optionally thermally conductive elements (traces, pads, connection elements, electrodes, etc.) can 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, alloy, silver alloy, zinc, brass, titanium, solder, and any of their components. The conductive material used can be optically opaque, translucent, and / or transparent at a desired wavelength (e.g., at least a portion of visible light) to, for example, mask, reflect from, absorb into, or pass through radiation (e.g., visible light). This aspect is also discussed elsewhere in this specification. As an actual example of a realizable conductive material, for example, Dupont™ ME602 or ME603 conductive ink can be utilized.

[0145] At 1008, additional circuit components (e.g., one or more typically off-the-shelf components including electronic components (e.g., various SMDs)) are attached to the contact areas on the film(s), e.g., by solder and / or an adhesive. For example, as previously contemplated herein, selected technology and packaged light source(s) (e.g., LED) may be provided here, and, e.g., depending on the embodiment, different elements of control and / or drive electronics, communication, sensing, connection (e.g., connector), reception (circuit board(s), carrier(s), etc.), and / or power supply (e.g., battery) may be provided.

[0146] For example, a suitable pick-and-place or other mounting device may be utilized for this purpose. Alternatively or additionally, printed electronics technology may be applied to actually manufacture at least a portion of the components (e.g., OLED (organic LED)) directly on the film(s) in situ. Thus, as will be understood by those skilled in the art, the execution of items 1006, 1008 to provide the desired circuit configuration in the multi-layer structure may overlap in time. However, the components prepared or installed herein may also include various optical elements such as lenses, reflectors, diffusers, masks, filters, etc.

[0147] Non-conductive and / or conductive adhesives may be utilized to fix the components onto the carrier. In some embodiments, mechanical fixation is effected or at least enhanced by a non-conductive adhesive material, while solder or other electrically highly conductive (although less so, adhesive-type) materials are used for electrical connection.

[0148] The selected elements may be subjected to further processing such as encapsulation (see, e.g., the comments related to the overcoat provided previously herein).

[0149] Item 1009 refers, in particular, to the provision and attachment of one or more at least partially pre - prepared modules (e.g., the aforementioned lighting module incorporating at least one light source 104 and, for example, a circuit board 602) or other “sub - assemblies”. A “sub - assembly” can incorporate what was initially provided on a separate secondary substrate (e.g., a circuit board) with the following: a circuit design and electronics, e.g., several light sources (plural), ICs (plural), and / or various other elements or components, e.g., optical or structural ones (e.g., wall structures, diffusers, lenses, carrier elements, etc.). This has also been detailed previously in this specification.

[0150] Accordingly, at least some of the electronics and / or other elements of the final multilayer structure may be conveniently provided to the substrate film(s) via fully or partially pre - manufactured module(s) or sub - assemblies. Optionally, the relevant module or sub - assembly may be at least partially overmolded or generally covered with a protective material, such as a plastic layer, before attachment to the main substrate.

[0151] For example, adhesives, pressure, and / or heat can be used for the mechanical bonding of the module or sub - assembly to the primary (receiving) substrate. Solder, wiring, and conductive ink are examples of applicable options for providing electrical and / or thermal connections between elements of the module or sub - assembly and the remaining electrical and / or thermal elements on the main substrate. Item 1205 can also be performed, for example, on item 1204 or 1208. Accordingly, the illustrated positions are only mainly typical.

[0152] Furthermore, the circuit configuration generally included in the multilayer structure, for example, on a substrate film, may include at least one component or element selected from the group consisting of an electronic component, an electromechanical component, an electro-optical component, a radiation-emitting component, a light-emitting component, an LED (light-emitting diode), an OLED (organic LED), a side-shooting LED or other light source, a top-shooting LED or other light source, a bottom-shooting LED or other light source, a radiation-detecting component, a light-detecting or photosensitive component, a photodiode, a phototransistor, a photovoltaic device, a sensor, a micro-mechanical component, a switch, a touch switch, a touch panel, a proximity switch, a touch sensor, an atmospheric sensor, a temperature sensor, a pressure sensor, a moisture sensor, a gas sensor, a proximity sensor, a capacitive switch, a capacitance sensor, a projected capacitance sensor or switch, a single-electrode capacitive switch or sensor, a capacitive button, a multi-electrode capacitive switch or sensor, a self-capacitance sensor, a mutual-capacitance sensor, an inductive sensor, a sensor electrode, a micro-mechanical component, a UI element, a user input element, a vibration element, an acoustic generation element, a communication element, a transmitter, a receiver, a transceiver, an antenna, an infrared (IR) receiver or transmitter, a wireless communication element, a wireless tag, a radio tag, a tag reader, a data processing element, a microprocessor, a microcontroller, a digital signal processor, a signal processor, a programmable logic chip, an ASIC (application-specific integrated circuit), a data storage device element, and an electronic subassembly.

[0153] In some embodiments, prior to item 1012, or if item 1012 is present, a substrate film(s) that optionally already contains an electronic device (e.g., at least a part of a circuit design section and / or a light source or other circuit configuration) may optionally be formed (1010) using, for example, thermoforming or cold forming to exhibit a desired shape (e.g., at least locally a three-dimensional (essentially non-planar) shape). An applicable forming device (e.g., a thermoforming machine) may be utilized for this purpose. Additionally or alternatively, if an already established multilayer stack is designed to withstand such processing, at least some of the forming may occur after shaping.

[0154] In 1012, at least one light transmissive plastic layer, or generally layer 108, is provided on or preferably over a light source on a first side of the substrate film or is directly generated, and the plastic layer at least laterally surrounds or is adjacent to (see, e.g., FIG. 9) the light source(s) and optionally at least partially covers it (see, e.g., FIG. 1). In some embodiments, at least a partially prefabricated (e.g., preformed) layer 108 can be utilized in addition to or instead of the in-situ generation of layer 108 from raw material(s) on the first side of the substrate, and layer 108 can optionally (pre-)be configured with some features 103 (e.g., holes (blind and / or through holes)) for conveniently accommodating at least a part of the light source(s) and / or other elements (e.g., (other) electronic components). The features (e.g., indentations or holes) can be configured in layer 108 by subtractive techniques (e.g., cutting (curving, milling, drilling, or other processing processes)). Alternatively or additionally, the features can be prepared directly or essentially within layer 108 during its (in-situ) manufacture, e.g., its shaping, without the need to utilize subtractive techniques (e.g., those for later removing layer 108 material to provide the features). However, as previously mentioned herein, the prehub embodiments of layer 108 can be provided by, e.g., lamination, printing, or coating, at least a part of the reflector design (see also item 110e of 150 in FIG. 1 for example) before connecting layer 108 with the remainder of the overall multilayer structure, such as substrate film 102.

[0155] Preferably, the plurality of layers provided, which preferably include a plastic layer or, in some embodiments, preferably a thermoplastic or optionally a thermosetting layer(s) in some embodiments, are thus laminated onto the substrate(s) or manufactured in-situ through molding such as injection molding. The desired portions may be left clear, for example, considering a cover portion of a writing module or other module intended to receive a replaceable or generally accessible (e.g., inspectable or reprogrammable) component, or the material may be cleared later by mechanical or chemical treatment. And such a module may also include a (removable) movable cover portion for providing access to its interior.

[0156] The molding material(s) can be provided using multiple molding steps or shots or via a single step. The molding material can optionally flow, for example, through a substrate film, from one side to the opposite side thereof, through holes provided therein, or through the substrate material itself (e.g., a thinned portion / thinner portion). The molding material(s) may be at least mainly electrically insulating, and in many embodiments, is preferably at least mainly electrically insulating. An adhesion promoting material can be utilized on a film near the molded plastic.

[0157] In practice, at least one substrate film on which some features (e.g., a circuit configuration including light source(s), module(s), further optical features, etc.) are already provided can be used as an insert in an injection molding process applying at least one molding machine. When two films are used, both of them can be inserted within their own molding die halves such that a plastic layer is injected at least between them. Alternatively, the second film can be attached later to the assembly of the first film and the plastic layer, for example, by a suitable lamination technique utilizing an adhesive between them.

[0158] Some of the optical elements (e.g., lens structures, optical output coupling elements or diffusers) contemplated hereinbefore can be established at least partially during molding from either the (thermoplastic) material used and / or the film insert with a suitable mold.

[0159] Instead of or in addition to molding, for example (3D) printing can be utilized for the generation of plastic layers.

[0160] Regarding the overall thickness resulting from the obtained and stacked multi-layer structure, the thickness depends on the material used and the associated minimum material thickness that provides the required strength, for example, taking into account manufacturing and subsequent use. These aspects should be considered on a case-by-case basis. For example, the overall thickness of the structure can be on the order of a few millimeters as discussed elsewhere in this specification, but considerably thicker or thinner embodiments are also feasible.

[0161] In some embodiments, materials other than plastic(s) can be utilized within layer 108, for example, with reference to glass.

[0162] Item 1016 refers to some potential additional tasks (e.g., post-processing and installation work). Further layers, single-layer or multi-layer films, or generally additional features can be added to the multi-layer structure by, for example, heat, adhesives, or pressure, or suitable coating (e.g., deposition) procedures, without forgetting molding, printing, laminating, other possible positioning or fixing techniques, and subtractive techniques (e.g., laser processing). The layers can also be of protective, indicative, and / or aesthetic value (graphics, colors, figures, texts, numerical data, etc.) and can include, instead of or in addition to plastic, for example, fabrics, leathers, or rubber materials.

[0163] Additional elements (e.g., electronic devices, modules, components inside or parts of modules, and / or optical components) can be installed and fixed, for example, on the outer surface(s) of an existing structure (e.g., the outer surface of a film or a formed layer included according to an embodiment). For example, an optical feature (e.g., a lens structure or a diffuser) can be constructed or completed here by treating a thermoplastic layer or any additional layer or element thereon by adding material thereto or removing material therefrom (laser processing is one option).

[0164] Features potentially present in a multilayer structure can actually include various features discussed previously (e.g., diffusers, output coupling elements, optical masks, holes, graphics, protective and / or aesthetic (and / or tactilely preferred) films or layers). Such features can be provided at this stage or among items of any subsequent method, depending on their position and the general configuration in the resulting structure as well as other features included, as understood by those skilled in the art.

[0165] As discussed previously herein, some features, such as output coupling elements integrally or monolithically formed within a target material, can be provided by modifying the target material (e.g., the material of a substrate film, an additional film (e.g., 114, 116, 120, or 122), and / or a reflector design) through deformation optionally involving material stretching. For example, mechanical pressure introduced by pressing can be used for that purpose. Mechanical pressure-induced deformations (e.g., stretching, breaking, and / or undulating of the material) occurring inside the structure or on a previously defined back side of the structure (e.g., not visible during use) need not have any visually perceptible effect from outside the structure.

[0166] Furthermore, as discussed previously herein, features potentially provided to the structure by the method, either optionally as a coextruded film layer or through coating, printing, or molding, are or include at least one additional material layer having a refractive index lower than that of the plastic layer, and the at least one additional material layer and the plastic layer are optionally physically adjacent and optically connected. Thus, at least a portion of the light emitted by at least one light source, propagated within the plastic layer, and incident on the at least one additional material layer is reflected (returned) within the plastic layer or is essentially retained therein by total internal reflection, provided that the associated critical angle is exceeded. The at least one additional material layer may optionally include a thermoplastic material or an optically clear adhesive material or, for example, a primer.

[0167] Still further, the method - laminating together two or more layers included in the multilayer structure by means of a pressure-sensitive adhesive, an optically clear adhesive, a solvent, an ink, heat, pressure, or a hot melt; - additionally generating (e.g., printing or 3D printing) at least one layer (e.g., a plastic layer, a layer of at least one reflective layer, an additional material layer, an optical waveguide, an optical output coupling element, a diffuser, and / or other optical functional elements); - optionally providing a top-emitting light source, which is an LED, on the top-emitting light source arrangement side on the substrate film such that its contact pads face in a direction transverse to the surface of the substrate film and are in contact with a conductive adhesive also provided (e.g., dispensed) on the substrate film, the conductive adhesive being at least partially surrounded on the substrate film by a structural adhesive provided on the substrate film (this is a realizable way to operably change the top-emitting source to a side-emitting one), the contact pads being electrically connected to a circuit design portion;

[0168] Furthermore, the method may include interconnecting a plurality of modules together to construct a structure, where any or each module advantageously - one or more light sources, and - at least a portion of a substrate film, and - optionally, at least one of a circuit design portion including a light source drive circuit and / or capacitive sensing electrodes, or comprises at least a portion of a layer of a reflector design portion and / or at least a portion of a plastic layer.

[0169] For example, an electronic device and / or a lighting module (e.g., including a light source, a circuit design portion, and optionally additional circuits such as a control circuit) may be manufactured, and for example, although there is no electronic device, some simpler modules including, for example, a light transmissive and / or reflective material or structure may be produced and then connected together.

[0170] Any of the modules may span several layers of the multilayer structure. In addition to being able to construct a multilayer structure at least partially from modules of different characteristics, as previously contemplated elsewhere in this specification, some optionally mutually different or similar multilayer structures may be connected to establish a larger, more functionally versatile assembly.

[0171] Optionally, when complementary functionality for the structure (e.g., the aforementioned capacitive sensing of touch or touchless gestures) is implemented, the sensing electrodes of the circuit configuration can be configured (sized, positioned, etc.) with additional elements and layers, e.g., with their sensing regions or volumes defined by the relevant electric or electromagnetic fields positioned as needed, thereby covering, e.g., regions on the upper surface of the structure, and / or other regions 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 implemented, for example, by utilizing simulation or measurement activities. The required features can be built, for example, layer by layer into the existing structure, or installed at least partially as a prefabricated stack.

[0172] When connectors are provided, the connectors of the multilayer structure or assembly can be connected to the desired external connection elements (e.g., external devices, systems, or structures, such as the external connectors of a receiving device). For example, these two connectors can together form a plug and socket type of connection and interface. As used herein, the multilayer structure can also generally be positioned and attached to a larger assembly (e.g., an electronic receiving device, optionally a personal communication device, a computer, a household device, an industrial device, or in embodiments where the multilayer structure establishes part of the exterior or interior of a vehicle, such as a dashboard or panel, a vehicle).

[0173] In 1018, the execution of the method ends.

[0174] The scope of the present invention is determined by the appended claims and their equivalents. Those skilled in the art will understand that the disclosed embodiments are constructed for illustrative purposes only and that other configurations applying many of the above principles can be readily prepared to best suit each potential use scenario.

Claims

**Claim 1** An integrated optical functional multilayer structure (100, 200, 300, 400, 500, 600, 700, 800, 900, 1100, 1300, 1400, 1500), comprising: A flexible, optionally 3D formable and thermoplastic substrate film (102, 102a) arranged together with a circuit design part (106) comprising at least some electrical conductors; A light source (104) provided on a first side of the substrate film for internally illuminating (104a, 104b) at least a part of the structure for external perception (113); An optionally thermoplastic light-transmissive plastic layer (108) provided on the first side of the substrate film, the plastic layer at least laterally surrounding or adjacent to the light source (104) and optionally at least partially covering it, and the substrate film optionally comprising the same material or material layer as that of the plastic layer, or having at least a refractive index similar to or lower than that of the plastic layer, a light-transmissive plastic layer (108); A reflector design part (110) comprising at least one material layer, the reflector design part being configured to reflect light emitted by the light source and incident on the reflector design part, optionally towards the plastic layer, and optionally mainly specularly, a structure comprising the reflector design part (110). **Claim 2** The structure according to claim 1, wherein the reflectivity of the reflector design part is at least locally about 75%, more preferably at least about 90%, and most preferably at least about 95% at selected, optionally essentially all visible wavelengths of light. **Claim 3** (300, 900) The structure according to claim 1 or claim 2, wherein the reflector design part (110, 110a, 110b, 110c) is preferably configured on a preferably direct optical emission path from the light source so as to be aligned with a side surface of the plastic layer substantially transverse to the surface normal of the plastic layer and reflect light input-coupled from the light source and incident on the reflector design part into the plastic layer. **Claim 4** The reflector design part is configured on or within the plastic layer so as to reflect and guide the light emitted by the light source and incident on the reflector design part, and to output-couple the light from at least the plastic layer or the entire structure towards an output coupling region (112, 112a, 112b, 112c), and optionally towards the relevant surface normal of the plastic layer, and to propagate it, according to any one of claims 1 to 3.

5. The reflector design part is an electrically conductive material, a metal, optionally metal particles, and further optionally a metal provided on or within the base film or a further film, or a further film or layer comprised by the structure, a plurality of stacked and superposed material layers with at least two mutually different refractive indices, optionally defining a Bragg mirror, a thin film coating, optionally a PVD (physical vapor deposition) coating, and a structure according to any one of claims 1 to 4, locally comprising at least one element selected from the group consisting of ink or paint.

6. One or more parts of the reflector design part (110) are located on the side of the plastic layer that is equal to (110a), opposite to (110b), and / or crosses (110c) the side of the base film facing the first side that receives the light source (104), according to any one of claims 1 to 5.

7. Comprising at least one further, optionally printed material layer (114), optionally stacked and preferably in contact, on the reflector design part (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 and the plastic layer being optically connected, and optionally physically adjacent, so as to redirect at least part of the light emitted by the light source, propagated within the plastic layer, and incident on the at least one further material layer, back into the plastic layer by total internal reflection, the at least one further material layer optionally comprising or consisting of an optically clear adhesive or primer, a structure according to any one of claims 1 to 6.

8. The layer of said at least one further material layer (114) also comprises a receiving layer (102) for said light source (104), said layer of said optionally co-extruded multilayer type of said substrate film (102a), the structure according to claim 7.

9. Comprising an intermediate layer (116) between said plastic layer (108) and the layer of said at least one further material layer (114), said intermediate layer preferably comprising the same light-transmissive material as the light-transmissive material of said plastic layer or having at least a refractive index similar to that of said plastic layer, said layer of said intermediate layer and said at least one further material layer being optionally a constituent of a multilayer film (116a), and further optionally preferably a co-extruded multilayer film and / or a substrate-type multilayer film, receiving some elements such as an optical element, a circuit design part, or one or more electronic components, laminated on said plastic layer, the structure according to claim 7 or 8.

10. At least a part of said reflector design part (110, 110a, 110b) and said at least one further material layer (114) are on the same side, opposite sides, or both sides of said plastic layer (108) with respect to each other, the structure according to any one of claims 7 to 9.

11. The layer of said reflector design part (110), the layer of said at least one further material layer (114), and said plastic layer (108) are at least locally overlapped such that the material of said layer of said at least one further material layer is stacked between the material of said layer of said reflector design part and said plastic layer with respect to those materials, the structure according to any one of claims 7 to 10.

12. (1200) Said plastic layer defines a bent portion having an optionally bent angle of about 10 degrees or more, and at least a part of said reflector design part is essentially located on said plastic layer at its outer periphery and / or inner periphery, the structure according to any one of claims 1 to 11.

13. (400, 420, 1400, 1412, 1412b) At least a portion of the reflector design part is light transmissive and further optionally includes a diffusely filled material, in order to allow the incident light to propagate through for output coupling, and includes several holes (410) such as perforations, and the incident density and / or size of the holes preferably increase with the distance from the light source. The structure according to any one of claims 1 to 12.

14. Preferably along the optical path from the light source towards the outside of the structure, a diffuser (414), an essentially planar electrode (418), preferably at least semi-transparent or substantially transparent, optionally printed on the diffuser, optionally printed graphics (416, 416a) laterally adjacent to the electrode, The structure according to any one of claims 1 to 13, comprising at least one element selected from the group consisting of optionally semi-transparent, non-transparent type protective outer surface elements (416, 416b) (1500).

15. (600, 700) The reflector design part preferably has a collimating reflector surface (610) on the side of the plastic layer facing the side facing the first side of the base film that receives the light source, and optionally at least locally defines an essentially parabolic reflector. The structure according to any one of claims 1 to 14.

16. The light source (104) is centered (600) or off-centered (700) with respect to the axis of symmetry of the collimating reflector surface. The structure according to claim 15.

17. At least a portion of the reflector design part is positioned adjacent to the base film so as to be able to propagate the light input-coupled from the light source into the base film by reflection until it enters an output coupling region or output coupling volume that preferably allows the light to exit the base film through the plastic layer. The output coupling region or volume optionally comprises a deformed base portion, a coating, or a printed portion. The structure according to any one of claims 1 to 16.

18. The structure according to any one of claims 1 to 17, wherein the reflector design part is locally processed, preferably mechanically, chemically or electrically processed, and has modified reflection characteristics for redirecting and output-coupling light (118), optionally through the plastic layer, and includes an optionally deformed (e.g., stretched) part, such as a material stack part or a material layer part.

19. The structure according to any one of claims 1 to 18, wherein the plastic layer locally defines a surface feature or surface pattern that optionally includes a roughened or deformed region for output-coupling (118) light incident therein.

20. On the plastic layer, there are provided (500) several preferably printed, optionally scattering output-coupling elements (118) with spatially varying incident densities and / or dimensions preferably including at least thickness. The incident density, thickness, and / or one or more other dimensions of the output-coupling elements preferably increase with the distance from the light source so as to enhance output-coupling with the distance, and one or more of the several output-coupling elements optionally include a fluorescent, phosphorescent, thermochromic, or photochromic material. The structure according to any one of claims 1 to 19.

21. The structure according to any one of claims 1 to 20, comprising an overcoat (124) that at least partially covers the light-emitting part of the light source, and the overcoat layer optionally includes a light-transmissive material having a refractive index higher than that of the plastic layer.

22. The structure according to any one of claims 1 to 21, comprising a light output-coupling region (112, 112a, 112b, 112c) on the plastic layer, wherein the light source (104) is preferably located between at least a part of the reflector design part (110c) aligned substantially perpendicular to the light output-coupling region and the light output-coupling region, and the light source is aligned towards the at least part (110c) of the reflector design part with respect to its primary emission direction.

23. Comprising a circuit board (602) provided on the substrate film for receiving the light source (600, 900), the circuit board optionally further receiving a light guide (908) of a light-transmissive material covering the light source, a wall structure (902) of a light-transmissive and optionally clear material disposed around the periphery of the circuit board, and / or preferably an air gap or filling (909) between the wall structure and the light guide, and / or the circuit board optionally further comprising several holes (603) for enabling light transmission therethrough, the structure according to any one of claims 1 to 22.

24. In the optical path from the light source to the outside of the structure and on the surface of the plastic layer or a subsequent surface, an optical print layer, a coating or film containing a material (416, 416a, 416b) that is opaque or translucent with respect to the light emitted by the light source, an optical mask (412), optionally a recessed surface such as the surface of the plastic layer defining one or more prism recessed shapes (118; 1418), a layer (1412, 1412a) of an optically at least translucent material if not a transparent material having a refractive index lower than that of an optically subsequent adjacent material such as air, a layer (1412, 1412c) in which a high refractive index material (1414) and a low refractive index material (1416) alternate, a layer of an opaque material that is perforated, has holes, or is locally thinned or through-cut in some other way, and an adhesion promoting primer, the structure according to any one of claims 1 to 23.

25. The light source (104) is a semiconductor, a packaged semiconductor, a chip-on-board semiconductor, a bare chip, an electroluminescent or printed type light source, preferably an LED, optionally including a multicolor LED such as RGB (red - green - blue), the structure according to any one of claims 1 to 24.

26. The light-transmissive plastic layer (108) defines internal holes (103) for accommodating at least a portion of the at least one light source, the structure according to any one of claims 1 to 25.

27. At least one of the several electrical conductors (106a) of the circuit design unit (106) faces away from the light-transmissive plastic layer (108), and preferably is at least electrically, optionally physically, connected to the light source (104) and is partially or essentially positioned on the side of the reflector design unit. The structure according to any one of claims 1 to 26.

28. (150) At least a part (110e) of the reflector design unit (110) is located between the light-transmissive plastic layer (108) and the base film (102), and optionally is formed or laminated on the light-transmissive plastic layer (108). The structure according to any one of claims 1 to 27.

29. A multi-source multi-target illumination assembly (800), comprising two or more structures (801a, 801b) according to any one of the preceding claims, which are preferably stacked together and attached, and the light from each of the two or more structures is output-coupled through their respective at least partially non-overlapping output coupling regions (112a, 112b) to one or more surfaces of the assembly and / or onto an illuminated output coupling element (118; 812a, 812b) in or on the assembly. The multi-source multi-target illumination assembly (800).

30. A method (1000) for manufacturing an integrated optical function multi-layer structure, obtaining a base film (102) that is flexible, optionally 3D formable, and thermoplastic, and optionally a multi-layer film, wherein the base film is preferably provided with a circuit design unit having at least some electrical conductors additionally formed (e.g., printed) on the base film (1006), obtaining the base film (102) (1004), arranging at least one light source on a first side of the base film (1008, 1009), providing a light-transmissive plastic layer on the first side of the base film, optionally through molding, lamination, or 3D printing (1012), wherein the plastic layer surrounds or is adjacent to the light source at least laterally, and optionally at least partially covers it. Optionally, a reflector design (1014, 1014A, 1014B) is provided that comprises a stack of material layers and / or at least one material layer including an electrically conductive and / or metallic material layer, which optionally includes printing, coating, laminating, or molding, and the reflector design is configured to reflect light emitted by the at least one light source and incident on the reflector design, optionally towards the plastic layer, and optionally mainly specularly. **Claim 31** Optionally including providing at least one additional material layer as a coextruded film layer or through 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 and the plastic layer are optically connected, optionally physically adjacent, to redirect at least a portion of the light emitted by the at least one light source, propagated within the plastic layer, and incident on the at least one additional material layer back into the plastic layer by total internal reflection, and the at least one additional material layer optionally includes a thermoplastic material or an optically clear adhesive material or primer, according to the method of claim 30. **Claim 32** Laminating together two or more layers included in the multilayer structure by a pressure-sensitive adhesive, an optically clear adhesive, a solvent, ink, heat, pressure, or hot melt. Optionally additionally generating (e.g., printing or 3D printing) at least one layer (e.g., the plastic layer, a layer of at least one reflective layer, an additional material layer, a light guide, a light output coupling element, a diffuser, and / or other optical functional elements), and Providing on the top-emitting light source side of the substrate film a top-emitting light source, optionally an LED, the contact pads of which face in a direction transverse to the surface of the substrate film and contact a conductive adhesive provided on the substrate film, and electrically connecting the contact pads to the circuit design, including at least one step selected from the group consisting of, wherein the conductive adhesive is at least partially surrounded on the substrate film by a structural adhesive provided on the substrate film, according to the method of claim 30 or 31. **Claim 33** comprising interconnecting a plurality of modules together, each module being one or more of said at least one light source, at least a portion of said substrate film, optionally, at least one of a light source driving circuit and / or said circuit design part including a capacitive sensing electrode, or The method according to any one of claims 30 to 32, comprising at least a portion of a layer of said reflector design part and / or at least a portion of said plastic layer. **Claim 34** The method according to any one of claims 30 to 33, wherein said plastic layer is configured to have at least one hole that houses at least a portion of said at least one light source. **Claim 35** A light transmissive layer is provided at least in part as a pre-manufactured element that is initially separated from said first side of said substrate film, and preferably is arranged together with at least a portion of said reflector design part prior to attaching said light transmissive layer and said substrate film together, either directly or via one or more intermediate layers. The method according to any one of claims 30 to 34.

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