Illuminated composite pane having a bar-type coupling element

Abstract

The invention relates to an illuminated composite pane (10) at least comprising, in the following order: • - an outer pane (1) having an outer surface (I) and an inner surface (II); • - an intermediate layer (3) made of a plastics material; • - an inner pane (2) having an outer surface (III) and an inner surface (IV), the inner pane (2) having a refractive index (n_1) which is greater than a refractive index (n_2) of the intermediate layer (3); • - a bar-type coupling element (5), the bar-type coupling element (5) comprising two planar end faces (5.1, 5.2), which are opposite in a longitudinal direction of the bar-type coupling element (5), and a light exit face (5.3) therebetween, which extends in parallel with the longitudinal direction and faces the inner surface (IV) of the inner pane (2), wherein a first end face (5.1) is tilted toward the light exit face (5.3) and a second end face (5.2) is preferably orthogonal to the light exit face (5.3); and • - a light source (6) having a light emission surface (6.1) for emitting light (6.2, 6.3) which can be coupled into the inner pane (2),

Description

[0001]SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT Illuminated Laminated Glass with Rod-Shaped Coupling Element The invention relates to an illuminated laminated glass with a rod-shaped coupling element, a method for manufacturing the illuminated laminated glass, and a use of the laminated glass. Illuminated laminated glass is used in various technical fields, for example, in vehicles or buildings. These laminated glass typically comprise two glass panes spaced parallel to each other with respect to their main surfaces, with several intermediate layers, namely at least a bonding layer and a light-diffusing structure. To illuminate the laminated glass, a light source, typically a light-emitting diode (LED), can be arranged on a side edge surface or in a recess of one of the glass panes, so that light is coupled into the glass pane via the side edge surface or the edge surface of the recess and is diffused there as a result ofTotal internal reflection propagates. Often, the light is coupled back out of the glass pane by light-diffusing structures, thus creating the illumination. The shape of the light-diffusing structures is freely selectable, so that illuminated surfaces of any shape, for example as patterns, can be created. In the automotive sector, such illuminated laminated glass panes are particularly interesting as roof panes, through which the interior can be illuminated. But such illuminated laminated glass panes can also be used for other vehicle windows, as well as for windows in the building and architectural sector or in furnishings. Instead of illuminating an interior, the illuminated surfaces formed by the light-diffusing structures can also be used to display information, for example, directional arrows, status indicators, warnings, price lists, or similar. In practice, the light coupling at theThe side edge surface or in the recess achieves a satisfactory result, especially with homogeneous illumination of the pane across the entire surface, as the light can be efficiently coupled in across the entire edge surface. However, in certain applications, the light cannot be coupled into the pane at the edge surface, e.g., in panes bonded into a pane frame, such as roof windows of motor vehicles. Such panes usually also have a circularly ground edge surface ("C-grind"), which prevents efficient light coupling, since light coupling at an edge surface generally requires a smooth or flat pane edge. SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT Another way to couple light into a laminated pane is to arrange the light source on one of the main surfaces of the glass panes, i.e., a light introduction perpendicular to this surface. On the other side, the light sourceOn the opposite main surface of each glass pane, a light-deflecting element is arranged that deflects the light emitted from the light source back into the pane, so that the light is guided within the pane by total internal reflection. The light-deflecting element is, for example, a microprismatic film applied to the pane. Additionally, the edges of the pane can be provided with a reflective coating to prevent light loss across the edges. Examples of such laminated glass panes are known from WO 2024 / 017968 A1, WO 2024 / 104856 A1, CN 118167966 A, and US 2017 / 045666 A1. For light transmission via the side edge or perpendicular to one of the main surfaces, specific modifications to the laminated glass pane are required, which can complicate its manufacture. Therefore, there is a need for improved illuminated laminated glass panes that overcome the aforementioned disadvantages.The present invention is therefore based on the objective of providing a laminated glass pane in which lighting can be arranged or retrofitted without interfering with its manufacturing process. This objective is achieved according to the invention by an illuminated laminated glass pane as defined in claim 1. Preferred embodiments are described in the dependent claims. The illuminated laminated glass pane according to the invention comprises, in the following order, at least: - an outer pane with an outer surface and an inner surface; - an intermediate layer made of a plastic material; - an inner pane, preferably made of a first glass material, with an outer surface and an inner surface, wherein the inner pane has a refractive index greater than that of the intermediate layer; - a rod-shaped coupling element, preferably made of a second glass material, wherein the rod-shaped coupling element has two sections extending longitudinally in the direction of the rod.The coupling element comprises two opposing planar end faces and, between them, a light-emitting surface extending parallel to the longitudinal direction and facing the inner surface of the inner disk, wherein a first end face is tilted towards the light-emitting surface and a second end face is preferably orthogonal to the light-emitting surface; and SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT- a light source with a light-emitting surface for emitting light that can be coupled into the inner disk, wherein the light-emitting surface of the light source is arranged opposite the first end face or opposite the second end face. In simplified terms, the rod-shaped coupling element has a specific design, namely, it has two opposing planar end faces along its longitudinal direction, between which its light-emitting surface extends parallel to the longitudinal direction. The term "rod-shaped" refers to an elongated three-dimensional body.The coupling element is understood to be a rod-shaped element whose longitudinal extent is greater than its extent in a plane orthogonal to it; preferably, the longitudinal length between the opposing end faces (in the region of the light-emitting surface) is at least ten times greater than the diameter of a circumcircle determined in an orthogonal section through the rod-shaped coupling element. The light source is arranged on this rod-shaped coupling element, namely on one of the two end faces, such that its light-emitting surface faces the nearest adjacent end face, i.e., they are facing each other. Preferably, the light-emitting surface is connected to the respective end face, namely the first end face or the second end face, via an optically transparent, cured adhesive. Preferably, the optically transparent, cured adhesive has a refractive index that is at most 10% greater than the refractive index of the rod-shaped coupling element.The refractive index of the optically transparent adhesive (in the cured state) and the rod-shaped coupling element is particularly preferably identical, with light having a wavelength of 550 nm being the basis for comparison. Alternatively, an air gap can be provided between the light-emitting surface of the light source and the first or second end face, but this is not preferred. The light source preferably comprises at least one light-emitting diode (LED). The light source can be a single LED, but preferably it is an arrangement of several LEDs. The said arrangement is preferably installed in a common housing, for example as a linear arrangement in which the LEDs are arranged along a line. The electroluminescent material of the LED can be, for example, an inorganic semiconductor or an organic semiconductor.In the latter case, it is also referred to as an organic light-emitting diode (OLED). Preferably, the rod-shaped coupling element is configured to couple (for the human eye) visible light, i.e., light with wavelengths from 380 nm to 780 nm, into the inner disk SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT. Preferably, the light source is configured to emit visible light in the aforementioned wavelength ranges, i.e., electromagnetic radiation with emission maxima over the entire wavelength range visible to the human eye. Alternatively, preferably, the light source can also be configured to selectively generate visible light with a specific wavelength, e.g., a single wavelength, or electromagnetic radiation over a limited wavelength range (i.e., the emission maxima of the emitted radiation cover only a sub-range of the wavelengths visible to the human eye). This rangeThe wavelength can be, for example, at most 100 nm (the wavelength is then, for example, in the range of 500 nm to 600 nm), preferably at most 50 nm, 40 nm, 30 nm or 20 nm (with possible lower limits, independent of this, of at least 1 nm, 2 nm, 3 nm, 5 nm or 10 nm). The outer pane and the inner pane of the illuminated laminated glass each have an outer and an inner surface and a circumferential side edge running between them. For the purposes of the invention, the outer surface is defined as the main surface which, in the installed position, is intended to face the external environment. For the purposes of the invention, the inner surface is defined as the main surface which, in the installed position, is intended to face the interior. The inner surface of the outer pane and the outer surface of the inner pane face each other and are connected in the illuminated laminated glass according to the invention byThe interlayer of the plastic material is bonded together. Thus, the outer surface of the outer pane faces away from the interlayer, and the inner surface of the outer pane faces the interlayer. The outer surface of the inner pane faces the interlayer, and the inner surface of the inner pane faces away from the interlayer. The outer surface of the outer pane is designated as Side I. The inner surface of the outer pane is designated as Side II. The outer surface of the inner pane is designated as Side III. The inner surface of the inner pane is designated as Side IV. The inner and outer surfaces of the inner pane form interfaces with the adjacent medium, either the surrounding atmosphere or the interlayer. Preferably, the adjacent medium has a lower refractive index than theInner pane. A critical angle of total internal reflection, which describes a minimum angle of incidence at which light from an optically denser medium (higher refractive index) strikes an interface with an optically less dense medium (lower refractive index), SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT, is completely reflected back into the denser medium instead of passing into the less dense medium, can be determined with the following equation: ^^ = arcsin( ^ ^ ^ ^), where n1 is the refractive index of the inner disk and n2 is the refractive index of the adjacent (optically less dense) medium. The first end face of the rod-shaped coupling element is inclined or tilted (towards the light-emitting surface) such that at least a portion of the light emitted by the light source (or its light-emitting surface) enters the inner disk at an angle of coupling such that it strikes the outer surface (i.e., side III) of the inner disk at an angle (angle of incidence) greater than the critical angle for total internal reflection. The light ray is totally reflected at the outer surface of the inner disk with an angle of reflection equal to the angle of incidence. The light strikes the inner surface (i.e., side IV) of the inner disk at precisely this angle of incidence, where it is again totally reflected.The second end face has a tilt (considered as a magnitude) relative to a surface normal of the light-emitting surface in the range of 0° to 5°, preferably 1° to 3°. Particularly preferably, however, this tilt is perpendicular or orthogonal to the light-emitting surface of the rod-shaped coupling element. In simplified terms, the second end face is tilted by a second angle relative to the surface normal of the light-emitting surface. Preferably, however, the second end face is orthogonal to the light-emitting surface of the rod-shaped coupling element. In general, providing the coupling element with two opposing and planar end faces, at least one of which is tilted towards the light-emitting surface of the rod-shaped coupling element, has the advantage that the light source (depending on the desired embodiment of the invention) can be arranged on either of the two end faces.In other words, one and the same coupling element can be used for different applications, which can be advantageous, for example, with regard to the manufacturing and provision costs of the coupling element. Specifically, the light source can be positioned opposite the first (i.e., the tilted) end face; by tilting this face, light can then be easily coupled into the inner pane of the composite pane. The tilting of the first end face of the rod-shaped coupling element towards its light-emitting surface causes light rays running parallel to the inner surface of the inner pane to be refracted at the first end face of the SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT rod-shaped coupling element towards the inner pane and consequently coupled into the inner pane.The light source, with its light-emitting surface perpendicular to the inner surface of the inner pane, can be easily positioned opposite the first end face, for example, by connecting it to the inner surface of the inner pane. This arrangement has the advantage, for instance, that the light source itself can be easily connected to the inner surface of the inner pane, e.g., by bonding, resulting in a more compact design overall (especially compared to a light source positioned at an angle to the inner surface of the inner pane). This can be advantageous, for example, with regard to package dimensions (i.e., the required installation space) and simplify integration into existing vehicles or their window systems, e.g., in the preferred case of using the laminated pane as a vehicle roof window.Alternatively, the light source can also be positioned opposite the second end face, in which case a light-reflecting coating is provided on the first end face (see below for details). Positioning the light source opposite the second end face can be advantageous, for example, if the light source is to be located outside the edge area of ​​the vehicle windscreen, such as in the case of a retrofit lighting kit located outside an adhesive section or joining area of ​​the windscreen. In particular, if the second end face is positioned orthogonally to the light-emitting surface, the tilting of the first end face creates a rod-shaped coupling element, which facilitates the simple retrofitting of a laminated windscreen with a lighting unit.As explained above, the tilting of the first end face can be advantageous in itself; however, the embodiment just described, with a tilted first end face and a second end face orthogonal (to the light-emitting surface), can also be advantageous. The inventors have also recognized that the specific design of the two end faces can be advantageous in combination with a so-called "flooded housing"; that is, an arrangement of the light source and the rod-shaped coupling element in a kind of tray containing a medium (e.g., immersion oil or glycerin). The light does not escape into the surroundings and, as a result of repeated total internal reflection, propagates essentially without loss within the inner disk, reflecting back and forth between the two surfaces of the inner disk.As is customary in ray optics, the angle of incidence is defined as the angle that the light ray incident on the surface (SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT) makes with respect to the surface normal at the point of impact. The angle of reflection is also determined analogously with respect to the surface normal, as is the critical angle for total internal reflection. The medium adjacent to the inner surface (i.e., side IV) of the inner disk differs from the medium adjacent to the outer surface (i.e., side III) of the inner disk. The inner surface of the inner disk (side IV) borders the surrounding atmosphere, and the outer surface of the inner disk (side III) borders the interlayer of the composite disk.The medium adjacent to the outer surface (side III) is optically denser than the air adjacent to the inner surface (side IV); the intermediate image therefore has a higher refractive index than the surrounding atmosphere (air). Consequently, different critical angles of total internal reflection occur at the two surfaces, with the critical angle at the outer surface (side III) being larger than the critical angle at the inner surface (side IV). In this case, the first end face of the rod-shaped coupling element is designed such that at least some of the light is coupled into the inner disk at an angle of incidence such that it strikes the outer surface of the inner disk (side III) at an angle greater than the (larger of the two) critical angles of total internal reflection, namely the critical angle at the outer surface (side III).In simplified terms, the first end face of the rod-shaped coupling element is tilted towards the light-emitting surface in such a way that the light entering the inner disk strikes the interfaces of the inner disk at an angle of incidence that is greater than the larger of the two critical angles of the inner disk (here, the critical angle at the outer surface of the inner disk, i.e., the critical angle at side III of the inner disk). The light components entering the inner disk then propagate within the inner disk due to repeated total internal reflection at the interfaces, namely the inner surface and the outer surface of the inner disk.The light propagates within the inner pane until it either strikes the side edge surface of the inner pane and is extracted there, or strikes a light extraction means on the inner or outer surface of the inner pane, or on the surface of the intermediate layer immediately adjacent to the inner pane, or within the inner pane itself. This interruption of total internal reflection is achieved through light scattering, thereby extracting the light from the inner pane. The outer pane and the inner pane are preferably made of a first glass material, in particular soda-lime glass, and each have a thickness of, for example, 0.5 mm to 10 mm, preferably 1 mm to 5 mm. The inner pane is preferably made of clear glass or plastic to ensure efficient light transmission. The outer pane and the intermediate layer can also be tinted or colored.Preferably, the outer pane and / or the intermediate layer are tinted such that the light transmittance TL according to ISO 9050:2003 (determined using light type A and / or light type D65) for visible light, namely light with wavelengths from 380 nm to 780 nm, is a maximum of 7%, particularly preferably a maximum of 5%. The tinted outer pane and / or the tinted intermediate layer can be advantageous with regard to reduced light and energy transmission into the interior. Furthermore, the tinting can improve the visibility of the illuminated inner pane. Alternatively, preferably, the outer pane and / or the intermediate layer are tinted such that the light transmittance TL according to ISO 9050:2003 for visible light (see above) is a maximum of 30%, particularly preferably a maximum of 25%, 20%, 15%, or 12% (with lower limits, regardless of the above, of at least 8%, particularly preferably at least 9%, 10%, or 11%).The tinted outer pane and / or the tinted intermediate layer can be advantageous with regard to reduced light and energy transmission into the interior, while the illuminated inner pane remains sufficiently visible through this tint (e.g., to the human eye). The rod-shaped coupling element is made of a second glass material, which is preferably also a soda-lime glass. The use of soda-lime glass for the inner pane and the rod-shaped coupling element contributes to the coupling of the light beam without significant impairment. Preferably, the soda-lime glass of the outer pane, the inner pane, and / or the rod-shaped coupling element has the following glass composition, based on 100 wt.% of the total glass composition: - SiO₂: 67 to 75 wt.%, - Na₂O: 10 to 20 wt.%, - CaO: 5 to 15 wt.%, - MgO: 0 to 7 wt.%, - Al₂O₃: 0 to 5 wt.%, and - K₂O: 0 to 5 wt.%.-%SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT In addition to the aforementioned components and iron, the glass of the glass pane according to the invention may contain further components in small proportions. For example, the glass may contain SO3 as a refining agent in a proportion of 0.01 to 1.0 wt.%, chloride in a proportion of 0.01 to 0.03 wt.%, and TiO2 in a proportion of 0.001 to 0.03 wt.%. The intermediate layer is preferably formed from a thermoplastic film, for example based on polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or polyurethane (PU), and has a thickness of, for example, 0.3 mm to 1.0 mm. If the illuminated laminated pane has more than one intermediate layer, in embodiments at least one of them may have a thickness of only 25 µm to 100 µm, for example, 50 µm or 75 µm.Instead of glass panes, polymer panes made of a clear, transparent plastic can also be used as the outer and / or inner pane. Using an inner pane made of a clear, transparent plastic offers the advantage that a structured surface can be more easily embossed into the transparent plastic than into a glass pane. If a polymer film or layer is formed based on a material, this means, in the context of the invention, that the film or layer consists predominantly of that material, i.e., the proportion of the material is more than 50% by weight, preferably more than 60% by weight. Furthermore, the film or layer can contain other components, such as plasticizers, stabilizers, or UV or IR blockers. The illuminated laminated pane can be flat or, preferably, curved in one or more directions.In summary, the composite disc illuminated according to the invention can first be manufactured as a stack of layers consisting of an outer disc, an intermediate layer, and an inner disc. In a subsequent manufacturing step, this stack of layers can then be provided with the rod-shaped coupling element and the light source. The rod-shaped coupling element is specifically selected for its availability from a variety of suppliers and is therefore relatively inexpensive. Nevertheless, the desired tilting of the first end face, as required by the invention, can be achieved through the specific design of the end faces of the rod-shaped coupling element, for example, by a cutting and / or grinding process performed prior to its assembly. This ensures efficient coupling of the light emitted from the light-emitting surface of the light source.Furthermore, this tilting also allows light entering through the second end face and striking an inner surface of the first SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT end face to be reflected towards the light emission surface and consequently coupled into the inner pane. In simplified terms, different arrangements of the light emission surface of the light source can be achieved with just one rod-shaped coupling element, which can increase the versatility of use. The rod-shaped coupling element with the light source attached to it is particularly suitable for retrofitting existing laminated panes with lighting, since some laminated panes already have an intermediate layer and its lower refractive index compared to the inner pane can promote light transmission; the rod-shaped coupling element can therefore be attached to this intermediate layer, thus creating the illuminated laminated pane according to the invention.According to a preferred embodiment, the rod-shaped coupling element, when viewed in a section perpendicular to its longitudinal direction, has a triangular, square, rectangular, or semicircular cross-section. In the section viewed perpendicular to its longitudinal direction, the rod-shaped coupling element is therefore triangular, quadrilateral, square, rectangular, or, preferably, semicircular; in the preferred case, the rod-shaped coupling element is thus a semicircular rod with two semicircular end faces, a rectangular light-emitting surface, and an outer circumferential surface that is at least half cylindrical. However, the rod-shaped coupling element can also be a triangular or square rod (spatially speaking). The rod-shaped coupling element is therefore a conventional glass rod, which is available from a variety of suppliers and is thus relatively inexpensive. Preferably, the outer circumferential surface can also be provided with a reflective coating.According to a preferred embodiment, the first end face is tilted at a first tilt angle of at least 2°, preferably at least 5°, 10°, 20°, or 30° relative to a surface normal of the light-emitting surface, with possible upper limits (independent of this) of 60°, 50°, or 45°. In simplified terms, the longitudinal length of the rod-shaped coupling element is greater at its light-emitting surface than at its outer edge opposite the light-emitting surface; thus, the rod-shaped coupling element, as its largest spatial dimension, extends in the longitudinal direction in the region of the light-emitting surface. In other words, the first end face, with its inner surface facing the rod-shaped coupling element, faces the light-emitting surface and is therefore inclined towards it.By tilting the first end face, light entering the rod-shaped coupling element can be refracted towards the light-emitting surface (and thus towards the inner pane) SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT, thus achieving efficient coupling of the light emitted from the light-emitting surface of the light source. Furthermore, this tilt also allows light entering through the second end face and striking an inner surface of the first end face to be reflected towards the light-emitting surface and consequently coupled into the inner pane. The preferred longitudinal length of the rod-shaped coupling element is a maximum of 300 mm, 250 mm, 200 mm, 150 mm, or 100 mm (with possible lower limits, regardless of these, of at least 10 mm, 20 mm, 30 mm, 50 mm, 70 mm, or 90 mm).The width of the rod-shaped coupling element, measured orthogonally to its length, is preferably at most 50 mm, 45 mm, 40 mm, or 30 mm (with possible lower limits, independent of these, of at least 5 mm, 10 mm, 15 mm, 20 mm, or 25 mm). According to a preferred embodiment, the refractive index of the rod-shaped coupling element deviates from the refractive index of the inner disc by at most 10%, preferably at most 5%, 3%, 2%, or 1% (based on a wavelength of 550 nm); particularly preferably, they are identical. According to a preferred embodiment, the rod-shaped coupling element is bonded to the inside of the inner disc by means of an optically transparent adhesive, which preferably comprises a cured adhesive. The optically transparent adhesive is particularly preferably a cured adhesive. Thus, the rod-shaped coupling element is positioned on the inside of the inner disc by means of the optically transparent adhesive.If the adhesive contains a curable adhesive, it is cured, for example, by heat, exposure to electromagnetic radiation, and / or chemical processes. Curing preferably occurs through the application of heat or an increase in temperature and / or UV radiation. A material is curable if it can be irreversibly brought into a cured state. Typically, a curable material is a plastic that is brought into a polymer-crosslinked state through curing. This distinguishes a curable plastic significantly from a thermoplastic, which, although also optically transparent, can be reversibly softened by the application of heat. In contrast, a curable plastic cannot be returned to a flowable state once it has cured.An optically transparent, curable adhesive is therefore not a non-curable thermoplastic. SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT. The curable, optically transparent adhesive is based, for example, on silicone. Curable, optically transparent adhesives are particularly well-known under the acronym LOCA (liquid optically clear adhesive). After application, the LOCA is often cured by UV radiation. The curable, optically transparent adhesive can contain or consist of, for example, polyurethane (PU), polyacrylate, polyacetate resin, casting resin, epoxy resin, Acralyt, or a copolymer or mixture thereof. Advantageously, the curable, optically transparent adhesive consists of a casting resin, especially one based on polyurethane or silicone. A UV-curing polyacrylate is particularly preferred as a curable, optically transparent adhesive.The optically transparent adhesive preferably has a light transmittance TL according to ISO 9050:2003 (determined using light type A and / or light type D65) of at least 70% relative to the light source, particularly preferably at least 80%, and most preferably at least 90%. The use of an adhesive comprising a curable adhesive has the advantage that the rod-shaped coupling element can be permanently bonded to the inner surface of the inner pane, but this bond can also be subsequently applied (for example, in workshops or at an end customer's site) using commercially available UV and / or heat lamps. According to a preferred embodiment, the adhesive is an adhesive tape, and the coupling element is bonded to the inner pane via the adhesive tape. The adhesive tape preferably comprises an optically transparent, cured adhesive.In simplified terms, the rod-shaped coupling element is mounted to the inner surface of the inner pane using the adhesive tape, specifically the optically transparent type. This allows the rod-shaped coupling element to be retrofitted to existing laminated panes, enabling conventional laminated panes (especially those with an intermediate layer of plastic material) to be retrofitted with the rod-shaped coupling element and illuminated across their entire surface by the light source. According to a preferred embodiment, the refractive index of the adhesive differs from that of the inner pane by at most 10%, preferably at most 5%, 3%, 2%, or 1% (based on a wavelength of 550 nm); preferably, they are identical.Preferably, the refractive index of the adhesive deviates by no more than 10%, preferably by no more than 5%, 3%, 2%, or 1% (based on a wavelength of 550 nm) from the refractive index of the rod-shaped coupling element. This has the advantage that the light beam can exit the rod-shaped coupling element and enter the inner disk through the adhesive without significant impairment, preferably in a straight line. If the adhesive comprises several elements, the deviation of the refractive index of the adhesive from the refractive index of the inner disk, as defined above, refers to the average over all elements of the adhesive, preferably for each element of the adhesive individually. According to a preferred embodiment, the light-emitting surface of the light source is arranged orthogonally to the inner surface of the inner disk.In this context, "orthogonal" means that the light-emitting surface is perpendicular to the inner surface of the inner disk, averaged over a certain area, e.g., over at least 5 cm² or 10 cm² of the respective surfaces (with possible upper limits, independent of this, of no more than 50 cm² or 25 cm²). Furthermore, preferably, the first or second end face opposite the light-emitting surface of the light source is ground. The light-emitting surface emits its light in a plane orthogonal to the inner surface of the disk; preferably, this light enters the rod-shaped coupling element parallel to the inner surface of the disk at the first or second end face. If, which is also preferably the case, the end face of the rod-shaped coupling element opposite the light-emitting surface, i.e., the first or second end face, is ground, the efficiency of the light coupling at the respective end face can be increased.Preferably, the first or second end face opposite the light emission surface (i.e., the nearest adjacent one) has a regular surface structure, the polishing grade of the nearest adjacent end face is a value P2 or higher according to ISO 10110-8:2019, i.e., the ground end face has fewer than 80 micro-defects per 10 mm sample length, with the surface roughness R. qThe value is determined using the root mean square method of the standard. According to a preferred embodiment, an optical collimator is formed on the light-emitting surface; that is, a collimator is arranged between the light-emitting surface and the opposite first or second end face of the rod-shaped coupling element, so that the light is directed into the inner disk via the collimator. The collimator generates a light beam with a preferably substantially parallel path, or at least a less divergent, i.e., more concentrated, path, from the typically divergent light beam of the light source.This has the advantage that the entire light beam is directed at the first or second end face with the same angle of incidence, particularly with an angle of incidence which, in conjunction with the tilting of the first end face, ensures that the largest possible proportion of the light is coupled into the inner lens in such a way that total internal reflection occurs at the outer and inner surfaces, thereby optimizing the light output. SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT In its simplest form, the collimator is a type of converging lens with the light source positioned at its focal point. The collimator can be made of glass or a transparent plastic, particularly polycarbonate (PC) or polymethyl methacrylate (PMMA). If the light source consists of an array of several LEDs, a separate collimator can be provided for each LED.Preferably, a common collimator is used for the entire LED array. In the case of a linear LED array, for example, a rod-shaped collimator can be used, the length of which is at least equal to the length of the LED array. The collimator is, for example, glued to the light-emitting surface of the light source, or arranged with a certain light gap between the light-emitting surface and the end face directly opposite it (nearest adjacent). According to a preferred embodiment, the light-emitting surface is arranged opposite the second end face, and the first end face has a light-reflecting coating to reflect light emitted from the light-emitting surface into the rod-shaped coupling element towards the light-exiting surface.The light-emitting surface of the light source is thus arranged directly opposite the second end face, and the light emitted from the light-emitting surface enters the rod-shaped coupling element through it. A light-reflecting coating is applied to the outer surface of the first end face, facing away from the rod-shaped coupling element. This coating reflects most of the light emitted into the rod-shaped coupling element back towards the light-exiting surface; due to the tilt of the first end face, this reflection occurs at a certain angle. The light-reflecting coating is suitable for reflecting light, particularly light in a wavelength range of 380 nm to 780 nm. Preferably, the light-reflecting coating is suitable for reflecting at least 70%, more preferably at least 80%, 90%, or at least 98% of the light incident on the coating, thereby improving coupling into the inner disk.In this embodiment, a tilting of the first end face towards the light-emitting surface with a first tilting angle of at least 2° and an orthogonal arrangement of the second end face to the light-emitting surface, i.e., a second tilting angle of 0°, of the rod-shaped coupling element is preferred. In this preferred embodiment, the following results, depending on the larger of the two critical angles: ^. ^,^^^ between the inner disk and the intermediate layer (i.e., on side III) or the inner disk and the surrounding atmosphere (i.e., on side IV) the first tilt angle ^ ^ The first end face is as follows: SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT^^,^^^ = 90° − 2 ∗ ^1. Alternatively, the second end face can also be tilted relative to the light-emitting surface. In this case, the following relationship between the larger of the two critical angles results. ^,^^^ on side III or side IV, the first tilting angle ^ ^ , the second tilt angle ^^ and the refractive index of the inner pane ^ ^ : ^^,^^^ = 90° According to a preferred embodiment, a telescopic lens system is arranged in the emitted light between the light-emitting surface of the light source and the second end face to focus the light emitted by the light-emitting surface of the light source before it enters the rod-shaped coupling element, thereby improving coupling into the inner disk. Alternatively, the lens system can also be used to collimate the light emitted by the light source before it enters the rod-shaped coupling element, i.e., to generate a substantially parallel beam of light. This improves the homogeneity of the light coupled into the composite disk. Furthermore, the invention also includes a method for manufacturing an illuminated composite disk, in particular an illuminated composite disk according to one of the aforementioned embodiments, wherein at least: a) a layer stack is provided,which comprises in the following order: - an outer pane with an outer surface and an inner surface; - an intermediate layer made of a plastic material; - an inner pane made of a first glass material with an outer surface and an inner surface, wherein the inner pane has a refractive index greater than the refractive index of the intermediate layer; b) the layer stack is joined by lamination; c) a rod-shaped coupling element made of a second glass material is provided, wherein the rod-shaped coupling element comprises two planar end faces opposite each other in a longitudinal direction of the rod-shaped coupling element and between them a light-emitting surface extending parallel to the longitudinal direction, which faces the inner surface of the inner pane, wherein a first end face is tilted towards the light-emitting surface and a second end face is preferably orthogonal to the light-emitting surface.SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCTd) a light source with a light-emitting surface for emitting light that can be coupled into the inner pane is arranged opposite the first end face or opposite the second end face on the rod-shaped coupling element, ande) the rod-shaped coupling element with the light source arranged thereon is bonded to the inner surface of the inner pane by means of an optically transparent, cured adhesive. The invention also includes the use of an illuminated composite pane according to the invention as a window pane of a vehicle. A particularly preferred use is as a vehicle roof window, which is used to illuminate the vehicle interior. The vehicle can in principle be any land vehicle, watercraft, or aircraft, but is preferably a passenger car.Truck or rail vehicle. The composite pane according to the invention can also be used in buildings, for example as a window pane, glass facade, or glass door in exterior or interior areas, in particular as a window pane of a building or an interior space. The glazing element can also be used as a component of furniture, electrical appliances, furnishings, or as a furnishing. To simplify the presentation of the invention, aspects of the device, method, and use have each been explained separately, with explanations and preferred embodiments relating equally to the device, method, and use. If preferred features are described in connection with the device, it follows thatthat the method or use is also preferably designed and suitable accordingly. Conversely, if preferred features are described in connection with, for example, the method and / or the use, it follows that the device is also preferably designed accordingly. The various embodiments of the invention can be realized individually or in any combination. In particular, the features mentioned above and to be explained below can be used not only in the combinations specified, but also in other combinations or on their own.without departing from the scope of the present invention. Generally, "a" and "an" within this disclosure are to be read as indefinite articles and thus, unless expressly stated otherwise, always also as "at least one" or "at least one". SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCTI The invention is explained in more detail below with reference to figures. The figures are schematic representations and not to scale. The figures do not limit the invention in any way. They show: Fig. 1 a top view of an illuminated composite disc 10, Fig. 2 a cross-section along X–X' through the illuminated composite disc 10 from Fig. 1, Figs. 3-5 further embodiments of an illuminated composite disc 10 according to the invention in a cross-sectional view along X–X' or Y–Y', respectively.Fig. 6 shows an embodiment of a method according to the invention with reference to a flowchart. Figure 1 shows a top view of an illuminated composite pane 10 according to an embodiment of the invention. In the example shown, the illuminated composite pane 10 is a vehicle roof window. Viewed from above onto a vehicle (not shown), the illuminated composite pane 10 has an opaque masking area M, which is arranged around the perimeter of the illuminated composite pane 10 and surrounds a central transparent viewing area D in a frame-like manner. Figure 2 shows a cross-section along a line X–X' through the illuminated composite pane 10 from Figure 1. As shown in Figure 2, the composite pane 10 comprises, in the following sequence, an outer pane 1 with an outer surface I and an inner surface II, wherein the outer pane 1 is a glass pane, an intermediate layer 3 made of a plastic material,An inner pane 2 with an outer surface III and an inner surface IV, wherein the inner pane 2 is a glass pane, a rod-shaped coupling element 5, and a light source 6. The outer pane 1 has the opaque masking area M (see also Figure 1). In the masking area M, a black cover print 9 is also applied to the inner surface II of the outer pane 1. Figure 2 shows the arrangement of the rod-shaped coupling element 5 according to the invention on the inner surface IV of the inner pane 2, namely, it is bonded to the inner surface IV of the inner pane 2 by means of an adhesive 7, for example, an optically transparent, cured adhesive. Figure 2 also shows that the rod-shaped coupling element 5 has two end faces 5.1,5.2 and a light-emitting surface 5.3 arranged between them. The light-emitting surface 5.3 of the rod-shaped coupling element 5SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT faces the inner surface IV of the inner disk 2. The first end face 5.1 is opposite to the second end face 5.2; these face each other. The first end face 5.1 is tilted towards the light-emitting surface 5.3, thus exhibiting a first tilt angle α1 relative to a surface normal of the light-emitting surface 5.3. In the example shown, this is approximately (+)10°, so that light emitted by the light source 6 can be reliably coupled into the inner disk 2. A second tilt angle α2 is approximately (+)1° in the example shown.so that the light incident on the second end face 5.2 is refracted somewhat towards the light-emitting surface 5.3 of the rod-shaped coupling element 5 upon entering it. Figure 3a shows an enlarged view of the illuminated composite disc 10 according to a second embodiment.The section shown in Figure 3a is a significant magnification compared to Figure 2; only an edge region of the illuminated composite disc 10 is shown as an example. In the example shown, a light-emitting surface 6.1 of the light source 6 is arranged opposite the first end face 5.1 of the rod-shaped coupling element 5. In the example shown, the rod-shaped coupling element 5 has a length of 70 mm measured between the first end face 5.1 and the second end face 5.2 (in the region of the light-exiting surface 5.3). Light 6.2 emitted from the light-emitting surface 6.1 strikes the tilted first end face 5.1 of the rod-shaped coupling element 5 and is refracted by it in such a way thatthat at least a large part of the emitted light rays 6.2 passes through the light-exiting surface 5.3 of the rod-shaped coupling element 5 and from there through the optically transparent adhesive 7 (for example, a cured adhesive) into the inner disk 2. The angle of incidence α is greater than a critical angle α. T In the example shown, the inner pane 2 has a refractive index of n1 = 1.51, and the PVB intermediate layer lying on the outer surface III of the inner pane 2 has a refractive index of n 2(PVB) = 1.48. The critical angle αT,III at a transition of the inner disk 2 to the intermediate layer 3, namely at the outer surface III of the inner disk 2, is given as follows:^^,^^^ = arcsin ( On the inner surface IV of the inner disk 2, opposite the outer surface III, the critical angle αT,IV is given as follows:^ = arcsin ^ SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT, where ambient air with a refractive index of n2(air) = 1.0 is present on the inner surface IV of the inner pane 2. Due to the larger angle of incidence αE compared to the critical angles at a contact surface between the inner pane 2 and the intermediate layer 3 αT,III, as well as at a contact surface between the inner pane 2 and the ambient air αT,IV, total internal reflection occurs. Figure 3b shows a top view of the first end face 5.1 of the rod-shaped coupling element 5, namely a section along a line Y–Y' (see Figure 1). In the top view (i.e., a view perpendicular to the longitudinal direction of the rod-shaped coupling element 5), its semicircular cross-section can be seen; in three dimensions, this is a semicircular rod, i.e., a round rod bisected along its longitudinal direction. In the example shown, the semi-circular rod has a maximum height of 5.0 mm (measured orthogonally to the light emission surface 5.3), i.e.Its outer circumferential surface has a radius of 2.5 mm. Therefore, efficient light coupling into the inner pane can be achieved using a rod-shaped coupling element, such as a half-round rod, which is available from various sources. Figure 4 shows another embodiment of the composite pane 10, namely an arrangement of the light-emitting surface 6.1 of the light source 6 opposite the second end face 5.2. As can be seen in Figure 4, the light 6.2 emitted by the light-emitting surface 6.1 enters the rod-shaped coupling element 5 at the second end face 5.2 and is reflected at the first end face 5.1, opposite the second end face 5.2, by a light-reflecting coating 5.4 arranged on its outer surface. Consequently, this light exits the rod-shaped coupling element 5 through the light-exiting surface 5.3 and the adhesive 7 and is coupled from there into the inner pane 2. Light emission area 6.In the example shown, 1 is designed as a collimator so that the entire light beam 6.2 is directed into the second end face 5.2 at the same angle of incidence, in particular at an angle of incidence which, in conjunction with the tilting of the first end face 5.1, ensures that the largest possible proportion of the light 6.2 is coupled into the inner pane 2 such that total internal reflection occurs at the outer surface III and the inner surface IV of the inner pane 2, thereby optimizing the light output. As already explained with reference to Figure 3a, total internal reflection occurs within the inner pane 2 at the outer surface III and the inner surface IV of the inner pane 2, so that the coupled light beam 6.2 propagates within the inner pane 2. SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT Figure 5 shows another embodiment of the illuminated composite pane 10, which is essentially the embodiment described in Figure 4. corresponds.However, in the embodiment shown in Figure 5, a telescopic lens system 8 is arranged between the light emission surface 6.1 and the second end face 5.2, which focuses the emitted light 6.2 before it enters the rod-shaped coupling element 5; thus, a focused beam of light 6.3 enters this element, thereby improving coupling into the inner disk 2.Figure 6 shows an embodiment of a method for manufacturing an illuminated composite pane 10, in particular one according to one of the aforementioned embodiments, wherein at least: P1 a layer stack is provided comprising in the following sequence: - an outer pane 1 with an outer surface I and an inner surface II; - an intermediate layer 3 made of a plastic material; - an inner pane 2 made of a first glass material with an outer surface III and an inner surface IV, wherein the inner pane 2 has a refractive index n1 that is greater than a refractive index n2 of the intermediate layer 3; P2 the layer stack is joined by lamination; P3 a rod-shaped coupling element 5 made of a second glass material is provided, wherein the rod-shaped coupling element 5 has two planar end faces 5.1, 5.2 opposite each other in a longitudinal direction X of the rod-shaped coupling element 5.2 and between them a light emission surface 5.3 extending parallel to the longitudinal direction X, which faces the inner surface IV of the inner disk 2, wherein a first end face 5.1 is tilted towards the light emission surface 5.3 and a second end face 5.2 is preferably orthogonal to the light emission surface 5.3, P4 a light source 6 with a light emission surface 6.1 for emitting light 6.2, 6.3 that can be coupled into the inner disk 2 is arranged opposite the first end face 5.1 or opposite the second end face 5.2 on the rod-shaped coupling element 5, and P5 the rod-shaped coupling element 5 with the light source 6 arranged thereon is bonded to the inner surface IV of the inner disk 2 by means of an optically transparent, cured adhesive 7.Using the aforementioned method, the composite pane 10 can be easily retrofitted with the rod-shaped coupling element 5, thereby obtaining the composite pane 10 illuminated according to the invention. SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT Reference numeral list 1 Outer pane 2 Inner pane 3 Intermediate layer 5 Rod-shaped coupling element 5.1 First end face (of the coupling element 5) 5.2 Second end face (of the coupling element 5) 5.3 Light emission surface 5.4 Light-reflecting coating 6 Light source 6.1 Light emission surface 6.2 Couplable light 6.3 bundled light 7 adhesive 8 telescopic lens system 9 masking pressure 10 illuminated composite pane I outer surface (of outer pane 1) II inner surface (of outer pane 1) III outer surface (of inner pane 2) IV inner surface (of inner pane 2) D viewing area of ​​outer pane 1 M masking area of ​​outer pane 1 n1 refractive index of inner pane 2 n2 refractive index of optically thinner medium (intermediate layer 3 or air) α1 first tilt angle of the first end face 5.1 α2 second tilt angle of the second end face 5.2 α. E Entry angle α T Limit angle SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCTX–X' 1st section line Y–Y' 2nd section line

Claims

1. SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCT Patent Claims 1. Illuminated composite pane (10) comprising at least in the following order: - an outer pane (1) with an outer surface (I) and an inner surface (II); - an intermediate layer (3) made of a plastic material; - an inner pane (2) with an outer surface (III) and an inner surface (IV), wherein the inner pane (2) has a refractive index (n1) greater than a refractive index (n2) of the intermediate layer (3); - a rod-shaped coupling element (5), wherein the rod-shaped coupling element (5) comprises two planar end faces (5.1, 5.2) opposite each other in a longitudinal direction of the rod-shaped coupling element (5) and between them a light-emitting surface (5.3) extending parallel to the longitudinal direction and facing the inner surface (IV) of the inner pane (2), wherein a first end face (5.1) is tilted towards the light-emitting surface (5.3) and a second end face (5.2) preferably orthogonal to the light emission surface (5.3); and a light source (6) with a light emission surface (6.1) for emitting light (6.2, 6.3) that can be coupled into the inner pane (2), wherein the light emission surface (6.1) of the light source (6) is arranged opposite the first end face (5.1) or opposite the second end face (5.2).

2. Illuminated composite pane (10) according to claim 1, wherein the rod-shaped coupling element (5) has a triangular, square, rectangular or semicircular cross-section in a section orthogonal to its longitudinal direction.

3. Illuminated composite disc (10) according to claim 1 or 2, wherein the first end face (5.1) is tilted by a first tilting angle (α1) of at least 2° relative to a surface normal of the light emission surface (5.3) towards the light emission surface (5.3).4.Illuminated composite pane (10) according to any one of claims 1 to 3, wherein the refractive index of the rod-shaped coupling element (5) differs by at most 10% from the refractive index (n1) of the inner pane (2).

5. Illuminated composite pane (10) according to any one of claims 1 to 4, wherein the rod-shaped coupling element (5) is bonded to the inner surface (IV) of the inner pane (2) by means of an optically transparent adhesive (7) comprising a cured adhesive.

6. Illuminated composite pane (10) according to claim 5, wherein the optically transparent adhesive (7) is an adhesive tape comprising an optically transparent cured adhesive.

7. Illuminated composite pane (10) according to claim 5 or 6, wherein the refractive index of the cured adhesive (7) differs by at most 10% from the refractive index (n1) of the inner pane (2).

8. Illuminated composite pane according to any one of claims 1 to 7, wherein the light-emitting surface (6.1) the light source (6) is arranged orthogonally to the inner surface (IV) of the inner disk (2).

9. Illuminated composite disk (10) according to any one of claims 1 to 8, wherein the first end face (5.1) or second end face (5.2) opposite the light emission surface (6.1) of the light source (6) is ground.

10. Illuminated composite disk (10) according to any one of claims 1 to 9, wherein an optical collimator is formed on the light emission surface (6.1).

11. Illuminated composite disc (10) according to claim 10, wherein the light emission surface (6.1) is arranged opposite the second end face (5.2), and wherein the first end face (5.1) has a light-reflecting coating (5.4) to reflect light (6.2) emitted from the light emission surface (6.1) into the rod-shaped coupling element (5) in the direction of the light exit surface (5.3).

12. Illuminated composite disc (10) according to claim 11, wherein between the light emission surface (6.1) a telescope lens system (8) is arranged between the light source (6) and the second end face (5.2) in order to focus the light (6.2) emitted from the light emission surface (6.1) of the light source (6) before it enters the rod-shaped coupling element (5).13.Method for manufacturing an illuminated laminated glass pane (10), in particular one according to any one of claims 1 to 12, wherein at least SAINT-GOBAIN SEKURIT FRANCE 2024244-WO-PCTa) a layer stack is provided comprising in the following sequence: - an outer pane (1) with an outer surface (I) and an inner surface (II); - an intermediate layer (3) made of a plastic material; - an inner pane (2) made of a first glass material with an outer surface (III) and an inner surface (IV), wherein the inner pane (2) has a refractive index (n1) that is greater than a refractive index (n2) of the intermediate layer (3); b) the layer stack is joined by lamination; c) a rod-shaped coupling element (5) made of a second glass material is provided, wherein the rod-shaped coupling element (5) has two planar end faces (5.1, 5.2) opposite each other in a longitudinal direction of the rod-shaped coupling element (5).2) and between them a light emission surface (5.3) extending parallel to the longitudinal direction and facing the inner surface (IV) of the inner disk (2), wherein a first end face (5.1) is tilted towards the light emission surface (5.3) and a second end face (5.2) is preferably orthogonal to the light emission surface (5.3), d) a light source (6) with a light emission surface (6.1) for emitting light (6.2, 6.3) that can be coupled into the inner disk (2) is arranged opposite the first end face (5.1) or opposite the second end face (5.2) on the rod-shaped coupling element (5), and e) the rod-shaped coupling element (5) with the light source (6) arranged thereon is bonded to the inner surface (IV) of the inner disk (2) by means of an optically transparent, cured adhesive (7).

14. Method according to claim 13, wherein in step d) the light emission surface (6.1) is opposite the second end face (5.2) is arranged, and wherein in step c) or d) the first end face (5.1) is provided with a light-reflecting coating (5.4) to reflect light (6.2) emitted from the light-emitting surface (6.1) into the rod-shaped coupling element (5) in the direction of the light-exiting surface (5.3).

15. Use of an illuminated laminated glass pane (10) according to any one of claims 1 to 12 as a window pane of a vehicle, a building or an interior, as a component of furniture or electrical appliances, as a component of furnishings or as a furnishing, preferably as a vehicle roof pane.

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