Vehicle glazing with printed light scatter

Abstract

This invention relates to a vehicle glass (3) having a light-guiding glass plate (8) with a printed material (11) and having a light-coupled input and a light-coupled output. Light from a light-emitting device (4) is coupled into the glass plate (8) through an edge region (5) of the glass plate (8), and the coupled light is coupled out from the glass plate (8) by means of the printed material (11) of the glass plate (8), wherein the printed material (11) is formed as a light-scattering structure composed of individual ink droplets (13), and the ink droplets (13) are formed by ink printed on the glass plate (8), and wherein a polymer coating layer (10) covers the cured ink droplets (13). According to the invention, the refractive index n of the glass plate (8) is set to... G The refractive index n of the printed material (11) P and the refractive index n of the capping layer (10) D Satisfying relation n G >n D And n P >n D Especially n P ≥n G >n D .

Description

Technical Field

[0001] This invention relates to a vehicle glass having a light guide glass plate with a printed material. The vehicle glass has a light guide glass plate with a printed material and has light coupling input and light coupling output. Light from a light-emitting device is coupled into the glass plate through an edge region of the glass plate, and the coupled light is coupled out from the glass plate by means of the printed material. The printed material is formed as a light-scattering structure composed of individual ink droplets, and the ink droplets are formed by ink printed on the glass plate. A polymer coating layer covers the cured ink droplets. Background Technology

[0002] A similar type of vehicle glass having a light guide glass plate with printed material is known from EP3702217A1. The printing is achieved by individual ink droplets spaced apart from each other, allowing visibility through the printed glass plate. However, this printing may cause optical distortion for an observer viewing a scene through the printed glass plate.

[0003] The objective of this invention is to provide a vehicle glass of the type described at the beginning, which has improvements in its optical properties. Summary of the Invention

[0004] In vehicle glass of the type described at the beginning, this task is solved according to the present invention by the following method: the refractive index n of the glass plate G The refractive index n of the printed material P and the refractive index n of the coating layer D Satisfying relation n G >n D And n P >n D .

[0005] Advantageous configurations of the invention are given in the dependent claims.

[0006] A vehicle glass with ambient lighting thus includes a glass plate as a light guide layer. The light guide glass plate is preferably made of mineral glass or plastic such as polycarbonate or similar materials. In one embodiment, the refractive index n in the visible light range (e.g., at 589.33 nm) is... G The value ranges from 1.50 to 1.58. The refractive index n of the coating layer... D Accordingly, in one embodiment within the visible light range (e.g., under light at 589.33 nm), the refractive index n of the printed material is 1.48 to 1.49. P In one corresponding embodiment, it is 1.50 to 1.90. The refractive index n of the glass plate in the visible light range (e.g., under light at 589.33 nm) is... GPreferably, it is ≥ 1.50, especially ≥ 1.52, for example, 1.58 for polycarbonate, or ≥ 1.50 for glass materials. An exemplary glass material for a glass plate has a refractive index n in the visible light range (e.g., at 589.33 nm). G Preferably, the light source is 1.505. The light from the light-emitting device is coupled into the glass plate through the edge region of the glass plate. The light-emitting device includes, for example, at least one LED or RGB-LED as a light source. Preferably, one light-emitting device is arranged on each of the two opposite side edges of the glass plate or vehicle glass.

[0007] The glass panel comprises a lower outer surface or lower main surface oriented toward the vehicle's interior space, and an upper outer surface or upper outer main surface oriented toward the external environment of the vehicle glass. Accordingly, the vehicle glass is constructed as a composite glass panel, thus having a second glass panel or outer panel laminated together with a first light-guiding glass panel via an interlayer (also called a cover layer and particularly a hot-melt adhesive film). The transparent cover layer is therefore preferably a layer made of polymeric materials such as PVB (polyvinyl butyral) or EVA (ethylene vinyl acetate). The cover layer has a refractive index n of, in particular, of 1.48. D .

[0008] Destination-appropriate settings: Refractive index n of the glass plate G The refractive index n of the printed material P and the refractive index n of the coating layer D Satisfying relation n P ≥n G >n D , preferably n P =n G To increase the scattering effect of printed materials, n is determined based on the size, shape, and proportion of the coupled output particles (also known as scattering particles) arranged in the printed material. P >n G That is in line with the purpose.

[0009] The capping layer has a refractive index n D The critical angle α for total internal reflection in the glass plate is determined. D The critical angle for total internal reflection (measured relative to the interface) at the interface between the glass plate and the printed structure is: α D =90°-arcsin(n D / n G Angle greater than α D Light enters the area covered by the printed light-scattering structure within the glass plate. The portion of light transmitted through the glass plate is therefore 1-(α). P / α D ). In a given n D and nG In this case, the intensity of the scattered light is determined by the refractive index of the printed light-scattering structure.

[0010] For example, for n D =1.48 and n G =1.52, critical angle α D =13.2°. Therefore, at the interface between the glass plate and the capping layer, only those rays that are incident on the interface at an angle less than the critical angle and thus very shallowly (flach) oriented relative to the interface are completely reflected. The glass plate acts as a light conductor for these very shallowly extended rays.

[0011] A glass plate has a printed image on its main surface. The printed image is formed as a light-scattering structure composed of individual ink droplets. The ink droplets are printed onto the glass plate using, in particular, transparent ink, especially by means of digital printing (inkjet printing). The ink preferably contains scattering particles. A coating layer covers the printed image or ink droplets (which is cured, for example, by means of UV light).

[0012] At the interface between the glass plate and the cover layer, ink droplets with a light-scattering structure exist. Light guided in the glass plate is scattered at the ink droplets and diffusely coupled out from the glass plate toward the vehicle interior space through the lower main surface, thus producing ambient lighting.

[0013] The refractive index n of printed matter or ink droplets P Refractive index n of the glass plate G Together, we determined which parts of the light guided in the glass plate could penetrate the ink droplet, and which parts were totally reflected at the interface.

[0014] The refractive index n of the ink droplet P It is a mixture of the refractive indices of the ink matrix and the scattering particles. The refractive index n of the ink droplet can be adjusted by varying the materials of the ink and the scattering particles and by mixing them. P .

[0015] In order to couple light into a light-scattering structure or ink droplet, the refractive index n of the ink droplet is... P It must be greater than the refractive index n of the coating layer. D (n) P >n D The greater the proportion of light coupled into the light-scattering structure or ink droplet, the brighter the ink droplet of the light-scattering structure will emit light.

[0016] For ambient lighting, it is preferable to couple as much light as possible into the glass plate and couple it out from the glass plate toward the vehicle interior space via light scattering. The ratio of light coupled into the ink droplets to light reflected at the interface and not coupled into the ink droplets is determined by the refractive index n. P and n D Decision. When nP ≥n G When n..., maximum optical coupling input and light scattering are achieved. P Approaching n D At that time, minimum optical coupling input and light scattering through the printed material are achieved, up to n p <n D At this point, there is virtually no perceptible light coupling input and light scattering through the printed material. For high-intensity ambient lighting, this aligns with the destination's target refractive index n of the printed material or ink droplets. P Adjusted to a refractive index n significantly greater than that of the capping layer D .

[0017] The thickness of the ink droplets is, for example, 0.001 mm to 0.2 mm. The thickness of the ink droplets is understood as the layer height formed by the ink droplets, i.e., the thickness or height of the printed surface (preferably the main surface) perpendicular to the glass plate. In the digital printing process of ink droplets, the light-scattering structure is printed with viscous ink and then cured with UV light. Here, the surface of the ink droplets exhibits a curved orientation at least at the edges, or the ink droplets as a whole exhibit an approximately plano-convex shape. This shape of the ink droplets is related to different refractive indices n. P and n D Together, they contribute to the effect of the optical lens.

[0018] If we assume the radius of the curved surface of the ink droplet is R, then the refractive power of the optical lens can be expressed as D = (n P -n D ) / n D / R estimation. This means that the effect of the ink droplet as an optical lens varies with the refractive index n. D The refractive index n increases linearly with the increase of the printed material. When viewing a high-contrast scene through a glass plate with this printing material, the refractive index n increases linearly with the printing material. P Undesirable distortions may occur due to the increase in [something].

[0019] The desired characteristics, namely high luminous intensity and low distortion achieved through light scattering, can therefore be determined by the structure of the light scattering or the refractive index n of the ink droplet. P To adjust, however, these characteristics change inversely. The highest intensity is at n. P ≥n G It reaches its peak at that time. However, this is accompanied by the highest distortion.

[0020] Reducing distortion by 50% already resulted in a significant decrease in luminous intensity to 25%. This was achieved simply by adjusting the refractive index n. P Trying to reduce distortion is ineffective.

[0021] When multiple individual ink droplets spaced apart from each other are printed, these droplets preferably have a size or diameter of about 0.04 mm to about 0.08 mm, more preferably about 0.05 mm to about 0.07 mm, and particularly about 0.07 mm, and the spacing between them is, for example, 0.1 mm or less, individual ink droplets can no longer be perceived by the eye as individual droplets. Instead, the area with such small ink droplets is perceived as a closed printed surface.

[0022] Therefore, if ink droplets are printed at such a small size that they are no longer discernible to the naked eye, no distortion will be observed. Here, each ink droplet acts like a microlens, scattering light over a wide range, thus producing a high degree of haze or turbidity. The portion of light that does not reach the ink droplets is transmitted undisturbed. The image presented in perspective is therefore a superposition of an undisturbed image and a blurred image.

[0023] Therefore, the desired distortion avoidance can be achieved through a printed material with a light-scattering structure composed of individual ink droplets, wherein the refractive index n of the glass plate is... G The refractive index n of the printed material P and the refractive index n of the coating layer D Satisfying relation n G >n D And n P >n D Preferably, n P ≥n G Especially n P >n G and / or n P ≥n G >n D .

[0024] In such a glass panel or vehicle window, a portion of the light from the external scene observed through the glass panel or vehicle window passes unobstructed through the gaps between spaced-apart ink droplets. Another portion of the light strikes the ink droplets and is more or less strongly diffracted or deflected due to the strong curvature of the droplet surfaces. The observer or vehicle occupant thus sees an unobstructed image (in transmission), which is superimposed with a hazy or diffused image. Therefore, preferably, since there are no large ink droplets, there is no distortion caused by the deflection of the light beam on large ink droplets. A large ink droplet is defined as one that can be perceived by the human eye, i.e., one that can significantly affect the visual image. Typically, this is assumed for the human eye to have an optical resolution of 2 arcminutes, particularly 1 arcminute. For example, at a standard distance of 25 cm, structures with a spacing of 0.3 mm are distinguishable.

[0025] To suit the intended purpose, each individual ink droplet is approximately constructed as a semi-ellipsoid. The ink has a viscosity such that, when applied to a glass plate, especially during digital printing, it forms droplets of this shape on the glass plate. The shape of the semi-ellipsoid is also determined by the velocity at which the ink impacts the glass plate and the rate at which the ink or droplet hardens during the drying process. These parameters are defined to give the ink droplet the desired shape after drying and curing. The semi-ellipsoid has a diameter and height at its base, in a ratio, for example, from 0.5 to 1.5. The lateral angle of the ink droplet is defined as the angle between a perpendicular line to the glass plate and a tangent drawn from the glass plate at the edge of the droplet on the circumference of the semi-ellipsoid, preferably about 5° to 10° at the base of the semi-ellipsoid or droplet, and preferably about 15° to 30° at half the height of the semi-ellipsoid or droplet.

[0026] For ease of description, the shape of the semi-ellipsoid is an approximation of the actual shape of the ink droplet. Therefore, minute deviations of the ink droplet from this shape can be ignored when describing the ink droplet.

[0027] A relatively narrow and tall ink droplet (i.e., its cross-sectional area at the interface is smaller than its height) results in less reflection of light incident from the glass plate at the interface between the droplet and the coating layer, and less emission through its lower main surface toward the vehicle's interior space, compared to a wider and shorter ink droplet (i.e., with less height). Therefore, the shape of the ink droplet can be used to adjust the optical coupling output and the light diffraction or deflection of the droplet as an optical lens.

[0028] The following refractive indexes should be set for the destination: - The refractive index n of the ink droplet P In the range of 1.51 to 1.54, especially 1.53 - The refractive index n of the light guide glass plate G It is 1.505, with -Refractive index n of the capping layer D In the range of 1.48 to 1.49, especially 1.485.

[0029] Particularly preferred is that the individual ink droplets, preferably printed by digital printing, have a size or diameter in the range of 0.04 mm to 0.08 mm, preferably about 0.05 mm to about 0.07 mm, and especially about 0.07 mm.

[0030] According to a preferred embodiment, the distance between the majority of ink droplets or all ink droplets is less than 0.1 mm. The distance between two adjacent ink droplets is therefore less than 0.1 mm, and preferably in the range of 0.02 mm to 0.08 mm.

[0031] According to another preferred embodiment, some of the ink droplets are in contact with each other. Through this contact, there are contact surfaces between the contacting ink droplets. Furthermore, gaps exist between the spaced-apart ink droplets. A capping layer covers the entire printed material, thereby covering the ink droplets themselves and the contact surfaces between them, and also filling the gaps. The contact with the capping layer reduces or completely eliminates optical interference caused by the ink droplets, such as interference caused by interfering reflection and / or interfering diffraction and / or interfering refraction and / or interfering scattering on the ink droplets. Such optical interference, for example, is reflection or refraction, which leads to distortion, turbidity, and / or opacity perceptible to the human eye. This results in a very transparent printed material with good values ​​in terms of light transmission and optical coupling output. This characteristic is also achieved by the following: light oriented perpendicularly to the printed and coated glass plate is less reflected, diffracted, or scattered at the contact surface or interface (especially >70° relative to the contact surface or interface) that is oriented substantially perpendicularly to the printed light guide glass plate, while light oriented shallowly (especially <20° relative to the contact surface or interface) to the printed and coated glass plate is similarly less reflected, diffracted, or scattered. Therefore, a preferred embodiment is designed such that the ink droplets have large lateral angles (rising from the boundary layer between the ink droplet and the glass plate to its height), forming a printed surface that extends as parallel as possible to the interface between the respective lateral sides.

[0032] According to a preferred embodiment, the printed material has at least two regions in which ink droplets are arranged at different intervals and / or have different sizes or diameters or different thicknesses. This creates regions that present optically different appearances for displaying patterns or logos, etc., and these regions are visible, in particular, through the scattering and coupling of light from ambient illumination.

[0033] According to a preferred embodiment, the vehicle glass has a second glass panel or outer panel that is laminated to the glass panel via a cover layer on the side of the glass panel having a printed image. The vehicle glass may also include another functional layer, such as a switchable layer with variable transparency or translucency.

[0034] According to a preferred embodiment, the vehicle glass is constructed as a transparent composite glass panel. In one embodiment, the vehicle glass can be formed as a partially transparent composite glass panel, for example, with a transmittance of less than 20%, preferably less than 10%.

[0035] The light-emitting device for introducing light, or at least one light source of such a light-emitting device, is preferably arranged on one of two lateral and opposite edges or edge regions of a glass plate or a composite glass plate having a glass plate, wherein the lateral edges relate to the left and right edges of a substantially rectangular glass plate or composite glass plate arranged on the roof of a vehicle. Optical coupling input of light can be achieved through the lateral edges, or through the side surfaces at the lateral edges, or through edge strips on the inner or lower main surface of the glass plate, for example by means of optical prisms (as disclosed in WO 2023 / 031460 A1) or other optical light guides or optical coupling input devices arranged on the edge strips.

[0036] Furthermore, a substantially perpendicular light coupling input can be provided from below, passing through the inner or lower main surface of the glass plate. In this case, for example, an optical device, such as a scattering layer or scattering element, is arranged opposite the light coupling input or light source, for example, on the inner main surface of the second glass plate. This optical device scatters or deflects the light coupled in, such that the light coupled in is deflected primarily at an angle corresponding to the total internal reflection angle of the second glass plate. Attached Figure Description

[0037] The invention will now be explained in more detail with reference to the accompanying drawings and embodiments of vehicle glass according to the invention. The drawings show: Figure 1 A perspective view showing a vehicle with a roof featuring vehicle windows; Figure 2 A schematic cross-sectional view shows the edge region of the light guide glass plate of the vehicle glass, with light reflected from the printing on the glass plate; Figure 3 A schematic cross-sectional view shows a light guide glass plate with light transmission and light scattering on a printout on the glass plate; Figure 4 A schematic cross-sectional view shows the area of ​​the glass plate with printed ink droplets. Figure 5 A schematic cross-sectional view of a glass plate is shown, illustrating ink droplets from a print, and the passage of scattered and unscattered light. Figure 6 A schematic cross-sectional view shows a glass plate with ink droplets of printed material and light reflected at the ink droplets; Figure 7 A schematic top view shows a glass plate with ink droplets applied by means of digital printing; Figure 8 A schematic top view is shown according to Figure 7 Ink droplets applied to a glass plate during the curing process; Figure 9 A schematic top view is shown according to Figure 8Ink droplets applied to and cured on a glass plate are covered by a coating layer; and Figure 10 A schematic cross-sectional view shows a vehicle glass according to another embodiment. Detailed Implementation

[0038] Vehicles, such as passenger cars, including the roof 1 ( Figure 1 The vehicle has a top opening 2 in which a vehicle glass 3 is arranged. The vehicle glass 3 is either fixedly arranged in the top opening 2 or constructed as a cover plate that is movably supported in the top opening 2 by means of a support device and can be adjusted between a closed position and a ventilated position or an open position in a manner known per se. The vehicle glass 3 can also be a fixed part or section of a roof module or panoramic roof. Light-emitting devices 4 are arranged on each of two laterally opposite edge regions 5 of the vehicle glass 3 and preferably extend along the corresponding side edge 7 of the vehicle glass 3 on the inner side 6 of the glass panel.

[0039] The vehicle glass 3 particularly comprises a composite glass panel having a glass panel 8 as an inner glass panel, an outer panel 9, and a polymer cover layer 10 as a connecting layer that connects the glass panel 8 to the outer panel 9, and comprising, for example, a laminate, a laminated film, or a hot-melt adhesive film, particularly made of PVB or EVA. The outer panel 9 is, for example, a colored glass panel, which can be either transparent or opaque. The inner glass panel 8 is particularly a transparent and light-guiding glass panel or a clear glass panel, preferably made of low-iron glass, which forms a light-guiding layer for coupling input light. The cover layer 10 covers a printout 11 disposed on the inner main surface 12 of the glass panel 8. The printout 11 is made using ink, which is preferably sprayed or printed onto the glass panel 8 by digital printing. Individual ink droplets 13 formed by the ink create a light-scattering structure for the printout 11.

[0040] Light-emitting device 4 (in) Figure 2 and 3 The light source (illustrated schematically) comprises, for example, multiple LEDs or RGB-LEDs arranged along the side edge 7 of the glass plate 8, and their light is coupled into the glass plate 8, for example, through the edge side surface 14. The coupled light rays 15 are reflected in the glass plate 8 at the inner interface 16 and the outer interface 17. The inner interface 16 corresponds to the inner main surface 12 covered by the cover layer 10. The outer interface 17 corresponds to the outer or lower main surface 18 of the glass plate 8 facing the vehicle interior space.

[0041] Glass plate 8 has a refractive index n of 1.505, in particular. G The printed matter 11 or ink droplet 13 has a refractive index n of, in particular, 1.52 or 1.53. P The capping layer 10 has a refractive index n of, in particular, of 1.485. D.

[0042] A ray 15 incident on interfaces 16 and 17 at an angle α less than the critical angle for total internal reflection is totally internally reflected in glass plate 8 and exits glass plate 8 without passing through the lower principal surface 18. The critical angle for total internal reflection (measured between the ray and the interface) is calculated according to the following formula: α D =90°-arcsin(n D / n G For n D =1.485 and n G =1.505, critical angle α D =9.35°. Therefore, at this critical angle, only very shallowly oriented rays 15 relative to interface 16 are totally internally reflected at the interface 16 of the glass plate 8 facing the cover layer 10. Thus, the glass plate 8 acts as a light guide for these shallowly oriented rays.

[0043] Light rays 15, which illuminate the ink droplets 13 of the printed material 11 at the internal interface 16, enter the ink droplets 13 at a corresponding angle and refractive index. They are reflected at the interface between the ink droplets 13 and the covering layer 10 covering the ink droplets 13, and are then coupled out as scattered light through the lower main surface 18 toward the interior space of the vehicle. This produces ambient lighting.

[0044] The light guided in the light guide glass plate 8 is limited by the critical angle of total internal reflection α. ​​The incident light beam L1 ( Figure 3 When it extends shallowly below the critical angle of total internal reflection α, it is totally reflected and continues to be propagated in the glass plate 8 as beam L2, while when it is incident more steeply, it penetrates into the covering layer 10 as beam L3.

[0045] The refractive index n of the scattering structure or ink droplet 13 P The refractive index n of glass plate 8 G Together, we determine which parts of the continuing propagated light L2 can penetrate the scattering structure or ink droplet 13 as beam L4, and which parts are totally reflected at interface 16 as beam L5.

[0046] The incident angle of the guided light L2 is limited by α. D =90°-arcsin(n D / n G At the same time, only those with at least α P =90°-arcsin(n P / n G Only light with an incident angle of 13 can enter the ink droplet.

[0047] In order to couple light into ink droplet 13, the refractive index n of ink droplet 13 is... P Therefore, it must be greater than the refractive index n of the covering layer.D (n) P >n D ).

[0048] Furthermore, through the refractive index n D It can be adjusted at α D and α max Within which angular range does beam L4 enter ink droplet 13? Between 0° and α... D Within the shallow incident angle range, it is totally reflected as beam L5. Therefore, beam L5 will not be coupled out from glass plate 8.

[0049] Each ink droplet 13 has, for example, in Figures 3 to 6 The shape is exemplarily shown in the figure. The surface of the cured ink droplet 13 has a curved orientation at least at the edge of the ink droplet 13, or the ink droplet 13 as a whole presents, for example, an approximately plano-convex shape, a hemispherical shape, or a semi-ellipsoidal shape. This shape of the ink droplet 13 is related to different refractive indices n. P and n D Together, they contribute to the optical lensing effect of ink droplet 13.

[0050] The distortion of the printed structure or ink droplet 13 (which can be described, for example, as a plano-convex lens) can be estimated using the lens grinding formula: D=(n P -n D ) / n D / R, Where R is the radius of the printed structure or ink droplet 13 (see...) Figure 4 Therefore, the lensing effect of ink droplet 13 increases with the refractive index n. P It increases linearly with the increase of .

[0051] When observing the vehicle environment through the glass plate 8 of the vehicle window, optical distortion may occur due to the lensing effect. To avoid this distortion, when printing multiple individual ink droplets 13 spaced apart from each other, these ink droplets 13 preferably have a size or diameter of about 0.04 mm to about 0.08 mm, preferably about 0.05 mm to about 0.07 mm, and particularly about 0.07 mm, and the spacing between them is, for example, 0.1 mm or less, each ink droplet 13 can no longer be perceived by the eye as an individual ink droplet 13. Instead, the area with such small ink droplets 13 is perceived as a closed or closed printed surface. Here, each ink droplet 13 acts like a microlens, scattering light over a wide range when light shines on the strongly curved surface of the ink droplet 13. This produces haze or turbidity. Figure 5 (Schematic illustration). The portion of light passing through the gaps between the ink droplets 13 and not illuminating the ink droplets 13 is transmitted undisturbed. For the observer, the image presented when looking through the glass plate 8 or vehicle glass is therefore a superposition of an undisturbed image and an image blurred due to light scattering, but with essentially no optical distortion.

[0052] Therefore, the desired distortion avoidance can be achieved by a printout 11 having a light-scattering structure composed of individual ink droplets 13, wherein, according to the invention, the refractive index n of the glass plate 8 is... G The refractive index n of printed material 7 or ink droplet 13 P and the refractive index n of the capping layer 10 D Satisfying relation n G >n D And n P >n D .

[0053] To meet the destination, each individual ink droplet is approximately constructed as a semi-ellipsoidal shape. Figure 6 The ink has such viscosity that, when applied to the glass plate 8, especially during digital printing, it prints ink droplets 13 thus shaped onto the glass plate 8. The shape of the semi-ellipsoid is also determined by the velocity at which the ink impacts the glass plate 8 and the hardening rate of the ink or ink droplets 13 during the drying process. These parameters are defined to give the ink droplets 13 the desired shape after drying and curing. The semi-ellipsoid has a diameter and height of its base, in a ratio, for example, 0.5 to 1.5. The lateral angle of the ink droplet 13 (defined as the angle between a perpendicular line to the glass plate 8 and a tangent at the edge of the ink droplet 13, extending from the glass plate 8 on the circumference of the semi-ellipsoid) is preferably about 5° to 10° at the base of the semi-ellipsoid or ink droplet 13, and preferably about 15° to 30° at half the height of the semi-ellipsoid or ink droplet 13.

[0054] According to another implementation method, ( Figures 7 to 9 Some of the ink droplets 13 are in contact with each other, and the gaps between the contact surfaces of the contacting ink droplets 13 and the spaced-apart ink droplets 13 are covered and filled by the coating layer 10. Contact with the coating layer 10 reduces or eliminates optical interference. The proportion of contacting ink droplets is, for example, about 20% of the entire printed material. The contacting ink droplets can be distributed regularly or irregularly. Alternatively, all ink droplets may be in contact with adjacent ink droplets, at least in one area of ​​the printed material.

[0055] Ink is sprayed onto glass plate 8, such that in one area of ​​the printed material, for example in a grid arrangement, ink droplets 13 with small spacing between each other are formed on glass plate 8. Figure 7 Depending on the properties of the ink (e.g., its viscosity), ink droplets 13 can change their original shape and move closer to each other during curing. Figure 8 After ink droplet 13 solidifies ( Figure 9 They come into contact with each other and form common contact surfaces. For example, the cover layer 10 applied during lamination ( Figure 9The coating layer 10 covers not only the ink droplets 13, but also the contact surface and any gaps between the ink droplets 13, filling the gaps and ensuring close contact with the ink droplets 13. Through the coating layer 10, the free interface of the ink droplets 13, which may cause undesirable optical interference due to total internal reflection, is also covered, thereby achieving more uniform light conduction and optical coupling output.

[0056] According to another implementation method ( Figure 10 The vehicle glass includes a modified structure in which the glass panel 8 preferably has a low-emissivity layer or Low-E layer 19 on its outer or lower main surface 18. The Low-E layer 19 reduces solar energy incident on the vehicle and heat radiation emitted from the vehicle's interior space, thereby reducing the feeling of cold for vehicle occupants. Furthermore, the outer panel 9 has an IR reflective coating 21 on its inner main surface 20 and black printing 22 in the area of ​​the side edge 7. The intermediate layer between the outer panel 9 and the inner glass panel 8 includes a laminated layer 23 in addition to the cover layer 10, which is connected to the outer panel 9 and is formed, for example, from dark PVB. Furthermore, a switchable film 24 (e.g., PDLC (polymer dispersed liquid crystal)) is embedded between the cover layer 10 and the laminated layer 23, which is powered via a contact portion 25. The contact portion 25 is connected to an energy supply device (not shown) via a contact area (not shown). A frame 27, made of, for example, PVB or TPU, surrounds the film 24 to compensate for thickness differences at the edges of the switchable film 24. The frame 27 has approximately the same thickness as the switchable membrane 24. Preferably, the frame 27 is slightly thinner than the switchable membrane 24, and for example has 98% to 85% of the thickness of the switchable membrane 24.

[0057] Optical coupling input originates from a light source (such as at least one LED or RGB-LED of the light-emitting device 4) and proceeds through an optical prism 26, which is bonded to a region on the lower or outer main surface 18 of the glass plate 8 that is vacated by a Low-E layer. Optical coupling input is performed, for example, according to optical coupling input known in WO2023031460A1.

[0058] Instead of or attached to the prism 26 shown herein, other types of light coupling input can be selected into the light guide glass plate 8, such as the light from a light source (e.g., a Top-LED) directed into the light guide glass plate and combined with the light source when using a scattering unit. The radiated light can thus be reflected and / or refracted into the glass plate to guide the light within the light guide glass plate by means of total internal reflection. The Top-LED is characterized by radiating light substantially perpendicular to the LED's mounting device (e.g., a circuit board), i.e., primarily with a radiation cone of less than 125°, particularly less than 90°, and preferably less than 60°.

[0059] The edge region 5 through which the light is coupled into the glass plate 8 thus includes the outer edge 7 and the edge strip 28 in the region of the lower main surface 18 of the glass plate 8 (in Figure 5 (Example shown and labeled). The edge strip 28 suitably has a width ranging from, for example, 0.5 cm to 10 cm. The width depends on, for example, the design of the glass sheet or composite glass sheet in its side edge or edge area.

[0060] Therefore, this embodiment does not provide transparent vehicle glass. In principle, the printed light guide glass plate 8 is intended for use in both transparent and opaque vehicle glass with ambient lighting.

[0061] List of reference numerals 1. Roof 2. Top opening 3. Vehicle glass 4. Light-emitting device 5. Edge Area 6. Inner side of the glass plate 7 Side edges 8 Glass Plates 9 outer panel 10 Covering layer 11 Printed materials 12 Main interior surface 13 Ink Drops 14. Side view 15. Light 16 Internal Interface 17 External Interface 18 Main side 19 Low-E layers 20 main side 21 Coating 22 Black Printing 23-layer laminate 24 Switchable membrane 25 Contact Department 26 Prisms 27 Framework 28 Edge stripes

Claims

1. A vehicle glass (3) having a light guide glass plate (8) with a printed material (11) and having a light-coupled input and a light-coupled output, wherein light from a light-emitting device (4) is coupled into the glass plate (8) through an edge region (5) of the glass plate (8), and the coupled light is coupled out from the glass plate (8) by means of the printed material (11) of the glass plate (8). in, The printed material (11) is formed as a light-scattering structure composed of individual ink droplets (13), and the ink droplets (13) are formed from ink printed on a glass plate (8). The polymer coating layer (10) covers the cured ink droplets (13). Its features are, The refractive index n of the glass plate (8) G The refractive index n of the printed material (11) P and the refractive index n of the capping layer (10) D Satisfying relation n G >n D And n P >n D Especially n P ≥n G >n D .

2. The vehicle glass (3) according to claim 1, characterized in that, The refractive index is: n P =1.50 to 1.90, n G =1.50 to 1.58, n D =1.48 to 1.

49.

3. The vehicle glass (3) according to claim 1 or 2, characterized in that, Each ink droplet (13) has a diameter in the range of 0.04 mm to 0.08 mm, preferably in the range of about 0.05 mm to about 0.07 mm, and particularly about 0.07 mm.

4. The vehicle glass (3) according to any one of claims 1 to 3, characterized in that, The majority of ink droplets (13) or all ink droplets (13) are spaced less than 0.1 mm apart, particularly in the range of 0.02 mm to 0.08 mm.

5. The vehicle glass (3) according to any one of claims 1 to 4, characterized in that, Each individual ink droplet (13) is arranged in a semi-ellipsoidal shape on the glass plate (8), and the ratio of the diameter of the base of the semi-ellipsoid to the height of the semi-ellipsoid is in the range of 0.5 to 1.

5.

6. The vehicle glass (3) according to any one of claims 1 to 5, characterized in that, Some of the ink droplets (13) are in contact with each other, and the contact surfaces of the contacting ink droplets (13) and the gaps between the ink droplets spaced apart from each other are covered or filled by the covering layer (10), and the contact with the covering layer (10) at least reduces or eliminates interference reflections.

7. The vehicle glass (3) according to any one of claims 1 to 6, characterized in that, The printed material (11) has at least two regions in which the ink droplets (13) are arranged with different spacings between each other and / or have different sizes or diameters.

8. The vehicle glass (3) according to any one of claims 1 to 7, characterized in that, The vehicle glass has a second glass panel or outer panel (9) which is laminated to the glass panel (8) on the side having the print (11) by means of the cover layer (10).

9. The vehicle glass (3) according to any one of claims 1 to 8, characterized in that, The vehicle's glass is constructed of a transparent composite glass panel.

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