Plate, device and method for the thermal stabilisation of a hologram element

Abstract

The invention relates to a plate (100) with thermal stabilisation of at least one hologram element (2), comprising at least one glass plate (1, 6) with an outer-side surface (I, III) and an inner-side surface (II, IV), at least one hologram element (2), arranged on the outer-side surface (I, III) or the inner-side surface (II, IV) of the at least one glass plate (1, 6), wherein the at least one hologram element (2) comprises a photopolymer, and at least two temperature stabilisation elements (3, 8, 11), wherein the at least two temperature stabilisation elements (3, 8, 11) are designed for stabilising the temperature of the at least one hologram element (2) to a target temperature.

Description

[0001] Disc, device and method for the thermal stabilization of a hologram element

[0002] The invention relates to a pane with thermal stabilization of at least one hologram element, a device comprising the pane, a method for thermal stabilization of at least one hologram element and the use of the pane.

[0003] It is common practice in the automotive and architectural sectors to incorporate additional features into glazing products to enhance the product's properties. A relevant example is the use of hologram elements applied to a pane and / or embedded in a laminated pane to provide visual information to the viewer in a pleasing manner.

[0004] Holograms can be used, for example, for head-up displays, where hologram elements are laminated between the panes of a composite pane. The hologram can contain recorded information. The hologram can be activated by light emitted by a projector, and thus the information recorded in the hologram can be displayed to the viewer. Head-up displays based on the principle of holography are disclosed, for example, in the publications WO 2012 / 156124 A1, US 2019 / 0056596 A1, US 10,394,032 B2, US 10,061,069 B2, US 2015 / 205138 A1, and WO 2022 / 101194 A1.

[0005] There are different types of holograms. These include, for example, reflection holograms and holograms based on the principle of guiding light waves within the hologram, so-called waveguide holograms.

[0006] A photopolymer can be used as the holographic material of a hologram element, in which various optical functions can be implemented, e.g. wavelength-selective mirrors that become active for defined viewing angles.

[0007] The use of a hologram element comprising a photopolymer for a head-up display is known, for example, from WO 2021 / 180471 A1. WO 2022 / 271905 A1 discloses a windshield comprising a reflective layer, wherein the reflective layer may comprise a holographic optical element.

[0008] One of the challenges in implementing such photopolymer hologram elements in glazing products, however, is the fact that the photopolymer is very sensitive to temperature changes. As soon as the temperature of the photopolymer deviates significantly from a predefined target temperature at which it is intended to be used, thermally induced physical dimensional changes cause a shift in the wavelength of the maximum reflected intensity. This deteriorates the optical function of the hologram element or, depending on the temperature change, is even lost completely. Good optical performance is only guaranteed within a range of ± 5°C around the predefined target temperature for the photopolymers currently in use. Therefore, even a naturally occurring temperature fluctuation, caused, for example, by a change in the environment, can be critical for such a hologram element.This can make it difficult or impossible to use a hologram element comprising a photopolymer in a glazing product exposed to environmental conditions.

[0009] DE112020006068T5 discloses a window pane system comprising a window pane to be mounted on a mobile body, a device arranged on the window pane and comprising an organic element made of an organic material, a temperature sensor configured to detect a glass temperature of the window pane, a temperature and humidity sensor configured to detect a temperature and humidity in an interior of the mobile body, and a control device comprising a circuit that determines, based on the glass temperature detected by the temperature sensor and the temperature and humidity in the interior detected by the temperature and humidity sensor, whether the glass temperature exceeds a dew point temperature when it is determined that the glass temperature is lower than or equal to the dew point temperature.an electric heating wire or film attached to the window pane or a defroster is switched on, and when the glass temperature detected by the temperature sensor exceeds a predetermined temperature, the electric heating wire or film is switched off, or the defroster is switched off. WO2022 / 214369A1 discloses a composite pane comprising at least: an outer pane, an inner pane, and a thermoplastic intermediate layer arranged between the outer and inner panes, an electrically conductive coating, and a reflective layer suitable for reflecting light, wherein the reflective layer may be a holographic optical element.

[0010] The present invention is therefore based on the object of providing a disc, a device and a method which enable a particularly precise thermal stabilization of a hologram element comprising a photopolymer.

[0011] The object of the present invention is achieved by a screen according to claim 1, a device according to claim 11, and a method according to claim 13. Preferred embodiments are set out in the subclaims. The invention also relates to the use of the screen as a projection surface for a head-up display.

[0012] The invention relates to a pane with thermal stabilization of at least one hologram element, comprising at least one glass pane with an outside surface and an inside surface, at least one hologram element arranged on the outside surface or the inside surface of the at least one glass pane, wherein the at least one hologram element comprises a photopolymer, and at least two temperature stabilization elements, wherein the at least two temperature stabilization elements are configured to temperature stabilize the at least one hologram element to a target temperature.

[0013] The pane is intended to separate the interior of a window opening from the exterior environment. The pane according to the invention comprises at least one glass pane, at least one hologram element, and at least two temperature stabilization elements. The glass pane has two surfaces (main surfaces), namely an exterior surface and an interior surface, and a circumferential edge surface between the two main surfaces. The exterior surface refers to the main surface that faces the exterior environment in the installed position. The interior surface refers to the main surface that faces the interior in the installed position. The at least one hologram element is arranged on said exterior surface or the interior surface of the glass pane.Preferably, the at least one hologram element is arranged on the interior surface of the glass pane, since the at least one hologram element is thus particularly protected from impairment by mechanical and / or chemical influences from the environment.

[0014] In one embodiment of the invention, the pane is designed as a composite pane, wherein one glass pane is connected to another glass pane via a thermoplastic intermediate layer. In the case of a composite pane, the one glass pane that must at least be present in the pane according to the invention is referred to below as “the glass pane,” while the glass pane that is additionally present in the composite pane is called “another glass pane” or “other glass pane.” In particular, a composite pane comprises an outer pane and an inner pane that are connected to one another via the thermoplastic intermediate layer. For the purposes of the invention, the “inner pane” refers to the glass pane of the composite pane that faces the interior. The “outer pane” refers to the glass pane that faces the outside environment.The glass pane can represent the inner pane or the outer pane of the laminated pane, and the other glass pane can represent the other one. The at least one hologram element can be located on the outer surface or the inner surface of the glass pane that is used as the inner pane or as the outer pane. If the glass pane is used as the outer pane of the laminated pane, the at least one hologram element is preferably located on the inner surface of the glass pane, as the at least one hologram element is thus protected from impairment by mechanical and / or chemical influences from the environment. If the glass pane represents the inner pane of a laminated pane, the at least one hologram element is protected from these environmental influences on both the outer surface and the inner surface of the glass pane.In one embodiment of the invention, the at least one hologram element is located on the outer surface of the glass pane used as the inner pane of the laminated pane, thereby enabling particularly advantageous temperature stabilization and regulation by a temperature stabilization element located between the inner pane and the outer pane. According to a further embodiment, the at least one hologram element is arranged on the interior surface of the glass pane when the glass pane is used as the inner pane of the laminated pane, since this makes it particularly easy to achieve temperature stabilization and regulation by a temperature stabilization element arranged outside (externally) the glass pane and aligned with the at least one hologram element. Such laminated panes are preferably used in the automotive sector as so-called laminated safety glass (VSG).The vehicle window can be, for example, a windshield, side window, rear window or roof window.

[0015] In an alternative embodiment of the invention, the pane according to the invention is a monolithic pane designed as a single glass pane. Apart from the glass pane with the at least one hologram element, no further glass pane is present. In the case of a single glass pane, the at least one hologram element is preferably arranged on the interior-side surface of the glass pane, as the at least one hologram element is thus protected from impairment by mechanical and / or chemical influences from the environment. The pane can be used in particular as so-called toughened safety glass (ESG), wherein the glass pane is thermally tempered. The monolithic vehicle pane can be, for example, a side window, rear window, or roof window.

[0016] According to an advantageous embodiment, the glass pane contains or consists of flat glass, preferably soda-lime glass, borosilicate glass or quartz glass. The glass can be made of clear glass or of tinted or colored glass. Clear glass is understood to be a glass pane which has an integrated light transmission according to ISO 9050 of at least 90%. Tinted or colored glass panes have a lower integrated light transmission. The same statements also apply to the additional glass pane (i.e. inner pane or outer pane) if the pane is a laminated pane. The thickness of the glass pane can be freely selected according to the requirements of the application. The thickness of the glass pane or the additional glass pane is usually between 0.5 mm and 5 mm.

[0017] The thermoplastic intermediate layer is preferably formed from at least one thermoplastic film, preferably a PVB film, EVA film, or PU film. Typical thicknesses for such a film range from 0.2 mm to 2 mm, in particular from 0.3 mm to 1 mm.

[0018] For the purposes of the invention, a hologram is a reflection hologram or a waveguide hologram arranged within a hologram element. The hologram element refers to the holographic medium in which the hologram is contained. The hologram element comprises a photopolymer. A hologram can be recorded in this photopolymer by exposure to a suitable light source. In the finished pane, the material of the hologram element is no longer light-sensitive because the photopolymer is altered during the process to such an extent that further recording of a hologram is no longer possible. The term hologram element refers both to the unexposed hologram element made of light-sensitive material and to the final hologram element with a recorded hologram. According to the invention, the final hologram element comprises at least one hologram, but preferably several individual holograms.

[0019] According to the invention, the at least one hologram element comprises a photopolymer. According to one embodiment, the at least one hologram element comprises, in addition to the photopolymer, a cover layer and / or a substrate layer. The photopolymer is preferably arranged between the cover layer and the substrate layer.

[0020] The thickness of the at least one hologram element is preferably from 10 pm to 500 pm, particularly preferably from 10 pm to 100 pm.

[0021] The photopolymer is not particularly limited. Preferably, the photopolymer comprises cross-linked polyurethane (PU) or polyacrylate.

[0022] The substrate layer of the at least one hologram element can be formed, for example, from polyamide (PA) film, polycarbonate (PC) film, or cellulose triacetate (TAC) film. The layer thickness of the substrate layer is preferably between 35 pm and 60 pm.

[0023] The cover layer of the at least one hologram element can be formed, for example, from polyamide (PA) film, polycarbonate (PC) film, cellulose triacetate (TAC) film, polymethyl methacrylate (PMMA) film, or polyethylene terephthalate (PET) film. The layer thickness of the cover layer is preferably between 35 pm and 60 pm.

[0024] In one embodiment, the photopolymer is formed as a photopolymer layer. The layer thickness of the photopolymer or photopolymer layer is preferably between 8 pm and 18 pm.

[0025] The at least one hologram element can be attached in or to the pane using conventional connecting means. Preferably, the at least one hologram element is laminated between two polyvinyl butyral (PVB) films, two ethylene-vinyl acetate (EVA) films, or two thermoplastic polyurethane (TPU) films. Alternatively, the at least one hologram element can be attached in or to the pane using an optically clear adhesive (OCA). Suitable optically clear adhesives are known to those skilled in the art. This allows for easy bonding of the at least one hologram element to other components of the pane.

[0026] According to the invention, the pane is provided with thermal stabilization for the at least one hologram element. In particular, the thermal stabilization is achieved with at least two temperature stabilization elements, which are configured to stabilize the temperature of the at least one hologram element at a target temperature.

[0027] For the purposes of the invention, the "target temperature" is a predefined temperature at which the photopolymer of the at least one hologram element is intended to fulfill its function as a holographic material. The target temperature is not particularly restricted. For example, a room temperature of 25°C can be defined as the target temperature. Alternatively, the target temperature can also be a higher temperature. Preferably, the target temperature is less than 90°C. More preferably, the target temperature is in a range of 15°C to 50°C, since this range is energetically advantageous.

[0028] According to the invention, "temperature stabilization" or "thermal stabilization" of the at least one hologram element means that the at least one hologram element is thermally stabilized using the temperature stabilization elements such that its temperature deviates as little as possible from the target temperature during its use to display the hologram. Preferably, the at least one hologram element is thermally stabilized such that its temperature lies within a range from (target temperature -10°C) to (target temperature +10°C), more preferably from (target temperature -5°C) to (target temperature +5°C).

[0029] The at least two temperature stabilizing elements according to the invention are not particularly limited as long as they are designed to stabilize the temperature of the at least one hologram element to the target temperature.

[0030] According to a preferred embodiment, the at least two temperature stabilizing elements are independently selected from the group consisting of a heatable coating, a thermally insulating coating and an (external) nozzle.

[0031] In one embodiment of the invention, at least one of the at least two temperature stabilizing elements is a heatable coating. With the aid of the heatable coating, the at least one hologram element can be heated efficiently, since a heatable coating itself can be heated quickly. According to one embodiment, the heatable coating comprises one or more, for example two, three or four, functional layers. According to a preferred embodiment, the functional layer comprises at least one metal, for example silver, gold, copper, nickel and / or chromium, or a metal alloy. The functional layer particularly preferably comprises at least 90 wt.% of the metal, in particular at least 99.9 wt.% of the metal. The functional layer can consist of the metal or the metal alloy. The functional layer particularly preferably comprises silver or a silver-containing alloy.Such a functional layer exhibits particularly advantageous heatability combined with high transmission in the visible spectral range. The thickness of the functional layer is preferably from 5 nm to 50 nm, particularly preferably from 8 nm to 25 nm. In this range of functional layer thicknesses, advantageously high transmission in the visible spectral range and particularly advantageous heatability are achieved.

[0032] Preferably, at least one dielectric layer is arranged between each two adjacent functional layers of the heatable coating. A further dielectric layer is preferably arranged below the first and / or above the last functional layer. A dielectric layer contains at least one individual layer made of a dielectric material, for example, containing a nitride such as silicon nitride or an oxide such as aluminum oxide. However, dielectric layers can also comprise several individual layers, for example, individual layers of a dielectric material, smoothing layers, adaptation layers, blocking layers, and / or anti-reflection layers. The thickness of a dielectric layer is, for example, from 10 nm to 200 nm.

[0033] This layer structure is generally obtained by a sequence of deposition processes carried out by a vacuum process, such as magnetic field-assisted sputtering.

[0034] According to a further embodiment, the functional layer of the heatable

[0035] Coating: indium tin oxide (ITO), fluorine-doped tin oxide (SnO2:F), or aluminum-doped zinc oxide (ZnO:Al). Such a functional layer preferably has a layer thickness of 8 nm to 25 nm, particularly preferably 13 nm to 19 nm. This is particularly advantageous with regard to the transparency, color neutrality, and sheet resistance of the heatable coating.

[0036] In a preferred embodiment, the heatable coating is provided with current collecting bars that are connected to the poles of a voltage source. Preferably, at least two outer current collecting bars intended for connection to a voltage source are connected to the heatable coating in such a way that a current path for a heating current is formed between the current collecting bars. The material for the current collecting bars is not particularly limited as long as it allows the formation of the current path. In a preferred embodiment, the current collecting bars comprise a transparent and electrically conductive enamel. Due to the transparency of such an enamel, it is not necessary to arrange the current collecting bars in the edge region of the pane, which is less visible to the observer. Instead, the current collecting bars can also be arranged in central regions of the pane. This is, for example,It is advantageous if the heatable coating is not applied over the entire surface. According to the invention, "full-surface" means that at least 95% of the surface is covered with the coating. In a further embodiment of the invention, the busbars are covered by at least one masking strip.

[0037] For the purposes of the present invention, "transparent enamel" means that the enamel preferably has a transmittance for visible light of more than 80%, more preferably more than 90%, even more preferably more than 95%.

[0038] According to the invention, the “edge area of ​​the pane” is the area of ​​the pane that is located near the installation position of the pane in the window opening.

[0039] The at least one masking strip comprises a colored, preferably black, material that can preferably be burned into a glass pane. The at least one masking strip is preferably opaque, in particular to serve as visual and UV protection, for example, for an adhesive bead.

[0040] "Opaque" means a light transmission of less than 30%, in particular less than 25%, for example less than 5%, in particular 0%. The at least one masking strip is a coating made up of one or more layers and serves to mask structures that would otherwise be visible through the pane when installed. In particular in the case of a windshield, the masking strip serves to mask an adhesive bead for bonding the windshield to a vehicle body, i.e. it prevents the generally irregularly applied adhesive bead from being visible to the outside, thus creating a harmonious overall impression of the windshield. On the other hand, the masking strip serves as UV protection for the adhesive material used. Continuous exposure to UV light damages the adhesive material and would loosen the bond between the pane and the vehicle body over time.The at least one masking strip can also be used, for example, to cover busbars, a temperature sensor and / or connection elements.

[0041] Preferably, a first masking strip is arranged in the edge region of the pane between the interior-side surface of the glass pane and the busbars such that it covers the busbars when the pane is viewed from the outside. Preferably, a second masking strip is further arranged in the edge region of the pane such that it covers the busbars when the pane is viewed from the interior. If the pane is designed as a composite pane, a first masking strip is preferably arranged between the interior-side surface of the outer pane and the busbars and a second masking strip is preferably arranged between the exterior surface of the inner pane and the busbars such that these masking strips cover the busbars from both sides of the pane.

[0042] In an advantageous embodiment, the heatable coating is a layer or a layer structure of several individual layers with a total thickness of less than or equal to 2 pm, particularly preferably less than or equal to 1 pm.

[0043] The total layer thickness of the heatable coating is preferably from 40 nm to 300 nm, particularly preferably from 45 nm to 250 nm. In this range for the total thickness of the heatable coating, at distances h between two busbars typical for vehicle windows, in particular windshields, and an operating voltage U in the range from 12 V to 15 V or 42 V to 48 V, a sufficiently high specific heating output P and, at the same time, a sufficiently high transmission are advantageously achieved. In addition, the heatable coating in this range for the total thickness also has particularly good reflective properties for the infrared range. If the total layer thickness of the heatable coating is too low, the sheet resistance Rouadrat is too high and thus the specific heating output P is too low, as well as reduced reflective properties for the infrared range.If the total thickness of the heatable coating is too great, the transmission through the window will be reduced too much, so that the requirements for the transmission of vehicle windows are not met.

[0044] In one embodiment of the invention, the heatable coating is in the form of thin metal wires, which preferably, when the pane is designed as a composite pane, run from one edge region of the inner or outer pane to the opposite edge region of the inner or outer pane. The wires can also overlap. The diameter of the metal wires is preferably less than 0.5 mm. The metal wires preferably contain at least one metal, for example silver, gold, copper, nickel and / or chromium, or a metal alloy. The metal wires particularly preferably contain at least 90 wt.% of the metal, in particular at least 99.9 wt.% of the metal.

[0045] The material of the heatable coating is preferably selected so that, depending on the wavelength of the light source used to create the hologram, the ghost image is as minimal as possible.

[0046] The heatable coating of the pane according to the invention preferably has a sheet resistance of less than or equal to 1 ohm / square, particularly preferably from 0.4 ohm / square to 0.9 ohm / square, most preferably from 0.5 ohm / square to 0.85 ohm / square, for example, approximately 0.7 ohm / square. In this sheet resistance range, high specific heating powers P are advantageously achieved. Furthermore, the heatable coating has particularly good reflective properties for the infrared range in this sheet resistance range.

[0047] In a preferred embodiment of the invention, the heatable coating is connected in an edge region of the pane to two busbars provided for connection to a voltage source such that a current path for a heating current is formed between the busbars. According to one embodiment, the heatable coating extends over 90% or more of the outside surface or the inside surface of the at least one glass pane. This arrangement allows the majority of the pane to be heated efficiently. In an alternative embodiment, the heatable coating is arranged only in a partial region of the outside surface or the inside surface of the at least one glass pane.According to this embodiment, the heatable coating can, for example, be arranged in the areas of the surface in which the at least one hologram element is also arranged, thus enabling targeted heating of the at least one hologram element, which is cost-effective and energy-efficient. Preferably, the at least one hologram element and the heatable coating are not arranged over the entire surface, and the outer dimensions of the heatable coating correspond to the outer dimensions of the at least one hologram element. This allows for energy-efficient temperature stabilization of the at least one hologram element, since only the corresponding areas where the at least one hologram element is arranged need to be thermally stabilized, not the entire pane.

[0048] If the pane is designed as a single pane of glass, the heatable coating is preferably arranged on the interior surface of the glass pane and is located between this surface of the glass pane and the at least one hologram element. According to this embodiment, the at least one hologram element is shielded as well as possible from external ambient conditions and can be additionally heated by the heatable coating. Furthermore, the perceptibility of the at least one hologram element is not impaired by the presence of the heatable coating, since the heatable coating is arranged behind the at least one hologram element for the viewer in the interior.

[0049] If, however, the pane is designed as a composite pane, the heatable coating and the at least one hologram element are preferably located between the outer pane and the inner pane of the composite pane, since this protects the heatable coating and the at least one hologram element from the influences of the external environment. The heatable coating is preferably arranged behind the at least one hologram element for the viewer in the interior, thereby preventing a reduction in the perceptibility of the at least one hologram element. This can be achieved, for example, by the heatable coating being arranged on the interior-side surface of the glass pane, which is used as the outer pane, and being located between this surface and the at least one hologram element. According to one embodiment, a further layer, e.g.the thermoplastic intermediate layer of the composite pane. In an alternative embodiment, the at least one hologram element is arranged on the outer surface of the glass pane used as the inner pane, and the heatable coating is arranged on the at least one hologram element, so that the at least one hologram element is arranged between the heatable coating and this surface. According to one embodiment, a further layer, e.g., the thermoplastic intermediate layer of the composite pane, can be arranged between the heatable coating and the at least one hologram element.

[0050] Preferably, the heatable coating and the at least one hologram element are arranged in direct contact with each other. This arrangement allows for targeted and precise heating of the at least one hologram element directly through the heatable coating.

[0051] According to one embodiment of the invention, the heatable coating is structured, for example, by laser ablation, in order to direct the electrical flow and heat generation in such a way that highly homogeneous heating is enabled.

[0052] In one embodiment of the invention, at least one of the at least two temperature stabilization elements is a thermally insulating coating. According to the invention, the "thermally insulating coating" is to be understood as a coating that provides the best possible thermal shielding for the at least one hologram element. The thermal shielding of the at least one hologram element is particularly important when a rapid change in ambient temperature occurs, caused, for example, by rain or snow, or, if the pane is to be used as a vehicle window, when entering or exiting a tunnel while the vehicle is moving.

[0053] According to an advantageous embodiment, the thermally insulating coating and the at least one hologram element are arranged in direct contact with each other. This arrangement allows for targeted thermal shielding of the at least one hologram element by the thermally insulating coating.

[0054] If the pane is designed as a single pane of glass, the thermally insulating coating is preferably arranged between the interior-facing surface of the one pane of glass and the at least one hologram element. This allows the at least one hologram element to be shielded as effectively as possible from the outside temperature.

[0055] If the pane is designed as a composite pane, the thermally insulating coating is arranged, according to one embodiment, between the interior-facing surface of the at least one glass pane used as the inner pane and the at least one hologram element. This arrangement places the at least one hologram element as far away as possible from the outside of the pane, which reduces the influence of the outside temperature on the at least one hologram element. Furthermore, in this arrangement, the at least one hologram element is further thermally shielded by the thermally insulating coating.

[0056] If the pane is designed as a composite pane, the thermally insulating coating is arranged between the inner pane and the outer pane according to a further embodiment. In particular, the thermally insulating coating can correspond to the thermoplastic intermediate layer of the composite pane. In this embodiment, the thickness of the thermoplastic intermediate layer is preferably in the range of 0.4 mm to 4 mm, particularly preferably 0.6 mm to 2 mm, whereby an increased thermally insulating effect can be achieved through the thermoplastic intermediate layer.In this embodiment, the at least one hologram element is preferably arranged on the outer surface of the glass pane used as the inner pane, so that the thermoplastic intermediate layer is located between the at least one hologram element and the outer side of the pane, thereby achieving good thermal shielding of the at least one hologram element. Alternatively, the at least one hologram element can be laminated between a first thermally insulating coating and a second thermally insulating coating, whereby a pane comprises the following structure, starting from the outer side of the pane: outer pane, first thermally insulating coating, the at least one hologram element, second thermally insulating coating, inner pane.In this embodiment, the first thermally insulating coating and the second thermally insulating coating preferably each correspond to the above-defined thermoplastic intermediate layer of the composite pane.

[0057] The material of the thermally insulating coating is not particularly limited as long as it is suitable for thermally shielding the at least one hologram element. Preferably, the material of the thermally insulating coating is a material with very low thermal conductivity. For example, the thermally insulating coating is selected from at least one plastic from the group consisting of polyvinyl butyral (PVB), an ethylene-vinyl acetate copolymer (EVA), and polyurethane (PU) film. In one embodiment, the thermally insulating coating is configured as a transparent aerogel. According to a further embodiment, the at least one masking strip can be used as a thermally insulating coating. The thermally insulating coating can be formed over the entire surface or cover only part of a surface.Preferably, the at least one hologram element and the thermally insulating coating are not arranged over the entire surface, and the external dimensions of the thermally insulating coating correspond to the external dimensions of the at least one hologram element. Such an arrangement is sufficient for the thermally insulating effect of the thermally insulating coating on the at least one hologram element. The thickness of the thermally insulating coating is preferably in the range from 0.2 mm to 2 mm, in particular from 0.3 mm to 1 mm. A sufficient thermally insulating effect can be achieved through the appropriate thickness.

[0058] In one embodiment of the invention, at least one of the at least two temperature stabilization elements is an external nozzle with a nozzle opening, wherein the nozzle opening is directed toward the at least one hologram element. In connection with the pane according to the invention, the nozzle is referred to as an "external nozzle" because this nozzle is not part of the pane itself, but is arranged externally.

[0059] The external nozzle is preferably directed toward the at least one hologram element such that it is completely encompassed by the air flow exiting the external nozzle. The center of the nozzle opening is preferably directed as precisely as possible toward the center of the at least one hologram element. This orientation allows for particularly efficient heating or cooling of the at least one hologram element by the external nozzle.

[0060] According to one embodiment, the external nozzle is included in a heating, ventilation, and air conditioning (HVAC) system. This allows the external nozzle to heat or cool the at least one hologram element as needed. In one embodiment, the external nozzle is a nozzle of the HVAC system that is fixedly aligned with the at least one hologram element and can be operated independently of other nozzles of the HVAC system. According to this embodiment, efficient temperature regulation and stabilization of the at least one hologram element can be achieved using the external nozzle, regardless of other settings of the HVAC system.

[0061] If the pane is designed as a single glass pane and at least one of the at least two temperature stabilizing elements is an external nozzle, the at least one hologram element is preferably arranged on the interior-side surface of the glass pane. However, if the pane is designed as a composite pane and at least one of the at least two temperature stabilizing elements is an external nozzle, the at least one hologram element is preferably arranged on the interior-side surface of the glass pane used as the inner pane. According to these arrangements, the at least one hologram element can be easily heated or cooled using the air jet from the external nozzle.

[0062] According to the invention, the pane comprises at least one hologram element, for example one hologram element, and at least two temperature stabilization elements, for example two temperature stabilization elements, wherein the at least two temperature stabilization elements are configured to stabilize the temperature of the at least one hologram element at the target temperature. By using at least two temperature stabilization elements, the most precise temperature stabilization possible can be achieved. In one embodiment of the invention, the pane comprises at least two hologram elements and at least two temperature stabilization elements, wherein in each case one temperature stabilization element can be configured to stabilize the temperature of a hologram element at the target temperature.The at least two temperature stabilization elements are preferably selected independently from the group consisting of a heatable coating, a thermally insulating coating, and an external nozzle. This means that the specific temperature stabilization elements can be combined as desired. In a preferred embodiment, the at least two temperature stabilization elements correspond to the heatable coating and the external nozzle. This combination of specific temperature stabilization elements allows for the most precise temperature stabilization possible with the lowest possible electrical energy consumption.

[0063] In one embodiment of the invention, the pane further comprises a temperature sensor configured to measure the temperature of the at least one hologram element. The temperature of the at least one hologram element can be measured directly or indirectly using the temperature sensor. A "direct" measurement, within the meaning of the invention, means that the temperature of the at least one hologram element itself is measured. An "indirect" measurement, on the other hand, means that the temperature of another component of the pane that is in contact with or in the immediate vicinity of the at least one hologram element is measured.

[0064] The temperature sensor is not particularly limited, as long as it is suitable for measuring the temperature of the at least one hologram element. The temperature sensor can be, for example, a thermocouple or an IR thermometer.

[0065] In one embodiment, the temperature sensor is in contact with the at least one hologram element. This allows for a direct temperature measurement of the at least one hologram element to be easily performed. In this embodiment, the temperature sensor is preferably a thermocouple. The thermocouple is preferably arranged in the edge region of the pane and covered by at least one masking strip, so that the thermocouple is not visible from the outside and inside of the pane. The at least one masking strip corresponds to the at least one masking strip defined above.

[0066] If the pane is designed as a single pane of glass, a first masking strip is preferably arranged in the edge region of the pane between the interior-side surface of the glass pane and the thermocouple such that it covers the thermocouple when the pane is viewed from the outside. Preferably, a second masking strip is further arranged in the edge region of the pane such that it covers the thermocouple when the pane is viewed from the interior. If the pane is designed as a composite pane, a first masking strip is preferably arranged between the interior-side surface of the outer pane and the thermocouple and a second masking strip is preferably arranged between the exterior surface of the inner pane and the thermocouple such that these masking strips cover the thermocouple from the outside and inside of the pane.

[0067] In a further embodiment, the temperature sensor is spaced apart from the at least one hologram element. This means that there is no direct contact between the at least one hologram element and the temperature sensor. If the temperature sensor is an IR thermometer, this can be arranged, for example, in the dashboard and aligned with its measuring range towards the at least one hologram element (“direct” measurement). In this case, the at least one hologram element is preferably arranged on the interior-side surface of the glass pane when the pane is designed as a single pane of glass, and preferably on the interior-side surface of the inner pane when the pane is designed as a composite pane, so that the measuring range of the IR thermometer is aligned directly towards the at least one hologram element and its temperature can thus be measured directly.If, however, the temperature sensor is a thermocouple, it can, for example, be in contact with the glass pane on which the at least one hologram element is arranged, so that an indirect temperature measurement can be carried out.

[0068] According to one embodiment, the pane can further comprise adhesive layers to bond the individual components of the pane together. The adhesive layers are preferably formed from an optically clear adhesive (OCA), as already mentioned above. Suitable optically clear adhesives are known to those skilled in the art.

[0069] The invention further relates to a device with thermal stabilization of at least one hologram element, comprising the pane according to the invention, a dashboard, and an HVAC system. The HVAC system comprises at least one nozzle arranged in the dashboard with a nozzle opening, the nozzle opening being aligned with the at least one hologram element, and the nozzle with the nozzle opening being a temperature stabilization element. This means that the nozzle can represent one of the at least two temperature stabilization elements of the pane or an additional temperature stabilization element of the device.

[0070] The nozzle with the nozzle opening of the device corresponds to the external nozzle defined above for the pane, whereby the nozzle is arranged in the device itself and not externally. The HVAC system of the device corresponds to the HVAC system defined above for the pane. According to the invention, at least the nozzle with the nozzle opening is used as a temperature stabilization element in the device. In addition to the nozzle with the nozzle opening, the device can further comprise the heatable coating defined above and / or the thermally insulating coating defined above as a temperature stabilization element. In one embodiment, the device further comprises a temperature sensor. The temperature sensor of the device corresponds to the temperature sensor of the pane according to the invention.According to a preferred embodiment, the temperature sensor in the device comprises an IR thermometer arranged in the dashboard and aligned with the at least one hologram element.

[0071] The invention further relates to a method for thermal stabilization of at least one hologram element, wherein the at least one hologram element is arranged in the pane according to the invention or in the device according to the invention, at least comprising the steps:

[0072] (a) providing the disc or device according to the invention, and

[0073] (b) stabilizing the temperature of the at least one hologram element to the target temperature with the at least two temperature stabilizing elements.

[0074] The embodiments described above in connection with the disc and device according to the invention also apply in the same way to the method according to the invention.

[0075] The hologram element can be provided in step (a) as an unexposed hologram element made of light-sensitive material or as the final hologram element with a recorded hologram. It is understood that when the unexposed hologram element is provided in step (a), the method according to the invention comprises, as an additional step, the recording of at least one hologram in the hologram element.

[0076] The provision of the pane according to the invention or the device according to the invention in step (a) is not particularly limited. Process steps for providing the individual elements of the pane or device are known to those skilled in the art.

[0077] According to the invention, the method is designed for the thermal stabilization of at least one hologram element. In particular, the thermal stabilization is achieved by step (b) of the method, wherein the temperature of the at least one hologram element is stabilized to the target temperature using the at least two temperature stabilization elements. Since in step (b) the temperature of the at least one hologram element is only regulated if the measured temperature deviates from the target temperature, the consumption of electrical energy for temperature regulation can be minimized, so that the method is energy-efficient and environmentally friendly. Furthermore, step (b) is preferably only carried out when the at least one hologram element is irradiated by a light source to generate a hologram, i.e., is active.If, however, the at least one hologram element is not irradiated by a light source to generate a hologram, i.e., it is inactive, step (b) is preferably not performed. Therefore, since temperature stabilization preferably only occurs when the at least one hologram element is active, electrical energy consumption can be reduced.

[0078] Preferably, step (b) comprises at least the following steps in order:

[0079] (i) measuring the temperature of the at least one hologram element with the temperature sensor,

[0080] (ii) comparing the measured temperature with the target temperature, and

[0081] (iii) optionally heating or cooling the at least one hologram element with the at least two temperature stabilizing elements if the measured temperature deviates from the target temperature.

[0082] In one embodiment of the invention, the temperature measured in step (i) is transmitted to a data acquisition device, whereupon this data acquisition device compares the measured temperature with the target temperature in step (ii). The target temperature is preferably set before step (b). If it is determined that the measured temperature deviates from the target temperature, the at least one hologram element is heated or cooled with the at least two temperature stabilization elements in step (iii). In one embodiment, a deviation of the measured temperature from the target temperature only occurs if the measured temperature lies outside a range of (target temperature - 10°C) to (target temperature + 10°C), more preferably from (target temperature - 5°C) to (target temperature + 5°C). This means that if the measured temperature lies within this range, the at least one hologram element is not heated or cooled.However, if the measured temperature lies outside this range, the at least one hologram element is heated or cooled. The data acquisition device itself can send a signal to the at least two temperature stabilization elements, whereupon the at least two temperature stabilization elements heat or cool the at least one hologram element. In a further embodiment, however, the data acquisition device can also be connected to a device for controlling the at least two temperature stabilization elements, to which it sends the result of the adjustment from step (ii), whereupon the control device sends a signal to the at least two temperature stabilization elements, whereupon the at least two temperature stabilization elements heat or cool the at least one hologram element.

[0083] In one embodiment of the invention, step (b) of the method is carried out multiple times so that the temperature of the at least one hologram element can be stabilized over the entire period of use. Preferably, the execution of step (b) is dynamically controlled. This ensures rapid regulation, for example, in the event of significant changes in ambient conditions, for example due to the occurrence of intense solar radiation, or when starting the vehicle. In one embodiment, step (b) of the method is carried out at least every 10 minutes, preferably at least every 8 minutes, more preferably at least every 5 minutes. This is advantageous under stable ambient conditions and at a constant vehicle speed.

[0084] If at least one of the at least two temperature stabilization elements according to an embodiment of the invention is a heatable coating, this can heat the at least one hologram element in step (b). In this embodiment, the target temperature is preferably higher than room temperature of 25°C.

[0085] If at least one of the at least two temperature stabilization elements according to an embodiment is an (external) nozzle, this can heat or cool the at least one hologram element in step (b). Since the (external) nozzle is suitable for heating and cooling the at least one hologram element, the target temperature can be selected arbitrarily, as mentioned above. In this embodiment, the target temperature preferably corresponds to room temperature of 25°C. The cooling function of the (external) nozzle can also contribute to reducing the influence of thermally induced aging on the at least one hologram element.

[0086] The invention further relates to the use of the pane according to the invention as a projection surface for a head-up display. During use, the pane is suitably mounted in a vehicle or in a structure. When used as a projection surface for a head-up display, the pane is preferably configured as a composite pane. Head-up displays are known to those skilled in the art and generally comprise an imaging unit and a projection surface. The imaging unit generates the image and may further comprise an optical module, e.g., a mirror optic, which redirects the image onto the projection surface.

[0087] The imaging unit comprises an illumination device, which may, for example, be one or more illumination elements selected from incandescent lamps, gas discharge lamps, light-emitting diodes, and / or laser light sources. Accordingly, visible light or laser light can be used for exposure.

[0088] The visual information is viewed from the space facing the inner pane of the laminated glass. This is usually an interior space where the viewer is located, e.g., a vehicle interior.

[0089] The invention is explained in more detail with reference to drawings and exemplary embodiments. The drawings are schematic representations and not to scale. The drawings do not limit the invention in any way. They show:

[0090] Fig. 1 is a plan view of an embodiment of a disc 100 according to the invention,

[0091] Fig. 2 shows a cross section through the embodiment of a pane 100 according to the invention shown in Fig. 1, wherein only one of the at least two temperature stabilizing elements is shown,

[0092] Fig. 3 shows a cross section through a further embodiment of a pane 100 according to the invention, wherein only one of the at least two temperature stabilizing elements is shown,

[0093] Fig. 4 shows a cross section through a further embodiment of a pane 100 according to the invention, wherein only one of the at least two temperature stabilizing elements is shown,

[0094] Fig. 5 shows a cross section through a further embodiment of a pane 100 according to the invention, wherein only one of the at least two temperature stabilizing elements is shown,

[0095] Fig. 6 shows a cross section through a further embodiment of a pane 100 according to the invention, wherein only one of the at least two temperature stabilizing elements is shown, Fig. 7 shows a cross section through an embodiment of a device 200 according to the invention, wherein only one of the at least two temperature stabilizing elements is shown,

[0096] Fig. 8 shows an embodiment of a method according to the invention using a flow chart.

[0097] Fig. 1 shows a plan view of an embodiment of a pane 100 according to the invention. In the embodiment shown in Fig. 1, the pane 100 has an upper edge O, a lower edge U and two side edges S.

[0098] Fig. 2 shows a cross-section through the embodiment of a pane 100 according to the invention shown in Fig. 1 along the section line XX'. The pane 100 comprises a glass pane 1 with an outside surface I and an inside surface II, a hologram element 2 arranged on the inside surface II of the glass pane 1, and a temperature stabilization element 3 arranged between the inside surface II of the glass pane 1 and the hologram element 2. According to the invention, the pane 100 comprises at least one further temperature stabilization element, which is not shown in Fig. 2, however. This at least one further temperature stabilization element can be selected from the group consisting of a heatable coating, a thermally insulating coating and an external nozzle.In the embodiment shown in Figure 2, the hologram element 2 and the temperature stabilization element 3 are present over the entire surface. In particular, one of the at least two temperature stabilization elements in this embodiment is a heatable coating 3. It is understood that further layers may be present in the pane 100. Preferably, the hologram element 2 is laminated between two polyvinyl butyral (PVB) films, two ethylene vinyl acetate (EVA) films, or two films made of thermoplastic polyurethane (TPU) (not shown). In addition, the pane 100 may comprise further adhesive layers (not shown) to bond the individual components of the pane 100 to one another. The adhesive layers are preferably formed from an optically clear adhesive.

[0099] For example, glass pane 1 is made of soda-lime glass and is 2.1 mm thick.

[0100] In the embodiment shown in Fig. 2, the hologram element 2 comprises a photopolymer, wherein the hologram element 2 is formed as a coating on the heatable coating 3 and has a thickness of, for example, 100 μm. Optionally, the hologram element 2 can also comprise a substrate layer in addition to the photopolymer, wherein the substrate layer is arranged directly adjacent to the heatable coating 3.

[0101] Fig. 3 shows a cross-section of a further embodiment of a pane 100 according to the invention. The pane 100 shown in cross-section in Fig. 3 differs from that shown in Fig. 2 in that the hologram element 2 and the heatable coating 3 are not designed to cover the entire surface, and the outer dimensions of the heatable coating 3 correspond to the outer dimensions of the hologram element 2.

[0102] Fig. 4 shows a cross-section of a further embodiment of a pane 100 according to the invention. The pane 100 shown in cross-section in Fig. 4 differs from the one shown in Fig. 3 in that the pane 100 further comprises a temperature sensor 4. The temperature sensor 4 is in direct contact with the hologram element 2 and can measure its temperature. If the measured temperature is lower than the target temperature, the hologram element 2 can be heated by the heatable coating 3. Preferably, the temperature sensor 4 has no contact with the heatable coating 3. This can be ensured, for example, by the pane 100 having a thermally insulating coating 5, which is located between the interior-side surface II of the glass pane 1 and the temperature sensor 4 and spaced the heatable coating 3 and the temperature sensor 4 from one another. In the embodiment shown in Fig.4, the outer dimensions of the thermally insulating coating 5 correspond to the outer dimensions of the temperature sensor 4. In the embodiment shown, the temperature sensor 4 is arranged in the edge region of the pane 100. Preferably, in the edge region of the pane 100, a first masking strip (not shown) is arranged between the interior-side surface II of the glass pane 1 and the temperature sensor 4 such that it covers the temperature sensor 4 from the outside of the pane 100. Preferably, a second masking strip (not shown) is further arranged in the edge region of the pane 100 such that it covers the temperature sensor 4 from the inside of the pane 100. Preferably, the temperature sensor 4 is fastened in the pane 100 with an adhesive layer (not shown), such as a layer of an optically clear adhesive.

[0103] Fig. 5 shows a cross-section of a further embodiment of a pane 100 according to the invention. The pane 100 shown in cross-section in Fig. 5 differs from that shown in Fig. 4 in that the pane 100 is designed as a composite pane, with the glass panes 1 and 6 being connected via a thermoplastic intermediate layer 7. The glass pane 1 is an outer pane and the glass pane 6 is an inner pane. In the composite pane, the glass pane can be present as the outer pane 1 and the further glass pane as the inner pane 6, or the glass pane can be present as the inner pane 6 and the further glass pane as the outer pane 1.In the embodiment shown, the heatable coating 3 is arranged on the interior-side surface II of the outer pane 1, and the hologram element 2 and the temperature sensor 4 are arranged on the exterior surface III of the inner pane 6, while the thermoplastic intermediate layer 7 is located between the heatable coating 3 and the hologram element 2. Alternatively to the embodiment shown, the heatable coating 3 can also be arranged in direct contact with the hologram element 2. In the embodiment shown, the temperature sensor 4 is arranged in the edge region of the pane 100. Preferably, a first masking strip (not shown) is arranged in the edge region of the pane 100 between the interior-side surface II of the glass pane 1 and the temperature sensor 4 such that it covers the temperature sensor 4 from the outside of the pane 100.Preferably, a second masking strip (not shown) is further arranged between the outer surface III of the inner pane 6 and the temperature sensor 4 such that it covers the temperature sensor 4 from the inside of the pane 100.

[0104] It is understood that further layers may be present in the pane 100. Preferably, the hologram element 2 is laminated between two polyvinyl butyral (PVB) films, two ethylene vinyl acetate (EVA) films, or two thermoplastic polyurethane (TPU) films (not shown). Furthermore, the pane 100 may further comprise adhesive layers (not shown) to bond the individual components of the pane 100 together. The adhesive layers are preferably formed from an optically clear adhesive.

[0105] For example, glass pane 1 is made of soda-lime glass and is 2.1 mm thick. Glass pane 6 is made of soda-lime glass and is 1.6 mm thick.

[0106] The thermoplastic intermediate layer 7 consists, for example, of polyvinyl butyral (PVB) and is 0.76 mm thick.

[0107] Fig. 6 shows a cross-section of a further embodiment of a pane 100 according to the invention. In the embodiment shown, the pane 100 is designed as a composite pane, as described above for Fig. 5. The hologram element 2 is arranged on the interior-side surface IV of the inner pane 6. A thermally insulating coating 8 is located between the hologram element 2 and the interior-side surface IV of the inner pane 6. By arranging it on the interior-side surface IV of the inner pane 6, the hologram element 2 can be protected as well as possible from external weather conditions. The thermally insulating coating 8 additionally enables thermal shielding of the hologram element 2 and thus its thermal stabilization. In the embodiment shown in Fig.In the pane 100 shown in Fig. 6, the hologram element 2 and the thermally insulating coating 8 are not designed to cover the entire surface, and the external dimensions of the thermally insulating coating 8 correspond to the external dimensions of the hologram element 2. According to the invention, the pane 100 comprises at least one further temperature stabilization element, which, however, is not shown in Fig. 6. This at least one further temperature stabilization element can be selected from the group consisting of a heatable coating, a thermally insulating coating, and an external nozzle.

[0108] It is understood that further layers may be present in the pane 100. Preferably, the hologram element 2 is laminated between two polyvinyl butyral (PVB) films, two ethylene vinyl acetate (EVA) films, or two thermoplastic polyurethane (TPU) films (not shown). Furthermore, the pane 100 may further comprise adhesive layers (not shown) to bond the individual components of the pane 100 together. The adhesive layers are preferably formed from an optically clear adhesive.

[0109] Fig. 7 shows a cross-section of an embodiment of a device 200 according to the invention. In this embodiment, the device 200 comprises a pane 100 according to the invention. The pane 100 is designed as a composite pane, as described above for Fig. 5. The hologram element 2 is arranged on the outer surface III of the inner pane 6. Alternatively, the hologram element 2 can also be arranged on the interior surface II of the outer pane 1 or the interior surface IV of the inner pane 6. The device 200 according to this embodiment further comprises a dashboard 9, an HVAC system 10, wherein the HVAC system 10 comprises a nozzle 11 arranged in the dashboard 9 with a nozzle opening 12, wherein the nozzle opening 12 is aligned with the at least one hologram element 2 and the nozzle 11 with the nozzle opening 12 is a temperature stabilization element, and a temperature sensor, which is an IR thermometer 13.Using the IR thermometer 13, the temperature of the hologram element 2 itself or, depending on the arrangement position of the hologram element 2, the ambient temperature of the hologram element 2 can be measured. This is illustrated in Fig. 7 with the dashed arrow. Depending on the measurement result, the temperature of the hologram element 2 can be regulated using the nozzle 11. If the measured temperature is lower than the target temperature, the hologram element 2 can be heated by the air stream exiting the nozzle opening 12 (indicated by the dashed lines in Fig. 7). Alternatively, if the measured temperature is higher than the target temperature, the hologram element 2 can be cooled by the air stream exiting the nozzle opening 12. According to the invention, the pane 100 comprises at least one further temperature stabilization element, which, however, is not shown in Fig. 7.This at least one further temperature stabilizing element can be selected from the group consisting of a heatable coating, a thermally insulating coating and an external nozzle.

[0110] Fig. 8 shows an embodiment of the method according to the invention for thermally stabilizing at least one hologram element 2 using a flow chart, wherein the at least one hologram element 2 is arranged in the pane 100 according to the invention or in the device 200 according to the invention, at least comprising the steps:

[0111] P1 Providing the disc 100 or the device 200, and

[0112] P2 Stabilizing the temperature of the at least one hologram element 2 to the target temperature with the at least two temperature stabilizing elements 3, 8, 11.

[0113] List of reference symbols:

[0114] 1 glass pane / outer pane

[0115] 2 hologram element

[0116] 3 Heatable coating

[0117] 4 Temperature sensor

[0118] 5 Thermally insulating coating

[0119] 6 Glass pane / inner pane

[0120] 7 Thermoplastic intermediate layer

[0121] 8 Thermally insulating coating

[0122] 9 Dashboard

[0123] 10 H VAC system

[0124] 11 Nozzle

[0125] 12 nozzle opening

[0126] 13 IR thermometers

[0127] 100 slices

[0128] 200 device

[0129] I Outside surface of the glass pane / outer pane 1

[0130] II Interior surface of the glass pane / outer pane 1

[0131] III Outer surface of the glass pane / inner pane 6

[0132] IV Interior surface of the glass pane / inner pane 6

[0133] O top edge

[0134] U bottom edge

[0135] S side edge

[0136] XX' cutting line

Claims

Patent claims 1. Pane (100) with thermal stabilization of at least one hologram element (2), comprising at least one glass pane (1, 6) with an outside surface (I, III) and an inside surface (II, IV), at least one hologram element (2) arranged on the outside surface (I, III) or the inside surface (II, IV) of the at least one glass pane (1, 6), wherein the at least one hologram element (2) comprises a photopolymer, and at least two temperature stabilization elements (3, 8, 11), wherein the at least two temperature stabilization elements (3, 8, 11) are for Temperature stabilization of the at least one hologram element (2) to a target temperature.

2. Pane (100) according to claim 1, wherein at least one of the at least two temperature stabilizing elements (3, 8, 11) is a heatable coating (3).

3. Pane (100) according to claim 1 or 2, wherein at least one of the at least two temperature stabilizing elements (3, 8, 11) is a thermally insulating coating (8) arranged between the interior-side surface (II, IV) of the at least one glass pane (1, 6) and the at least one hologram element (2).

4. Pane (100) according to claim 2, wherein the at least one hologram element (2) and the heatable coating (3) are not arranged over the entire surface and the outer dimensions of the heatable coating (3) correspond to the outer dimensions of the at least one hologram element (2).

5. Pane (100) according to claim 3, wherein the at least one hologram element (2) and the thermally insulating coating (8) are not arranged over the entire surface and the outer dimensions of the thermally insulating coating (8) correspond to the outer dimensions of the at least one hologram element (2).

6. Disc (100) according to one of claims 1 to 5, wherein at least one of the at least two temperature stabilizing elements (3, 8, 11) is an external nozzle (11) with a nozzle opening (12), wherein the nozzle opening (12) is aligned with the at least one hologram element (2).

7. A pane (100) according to any one of claims 1 to 6, further comprising a temperature sensor (4, 13) configured to measure the temperature of the at least one hologram element (2).

8. Disc (100) according to claim 7, wherein the temperature sensor (4) is in contact with the at least one hologram element (2).

9. A pane (100) according to any one of claims 2 to 8, wherein the heatable coating (3) is provided with current collecting bars connected to the poles of a voltage source, and the current collecting bars comprise a transparent and electrically conductive enamel.

10. Pane (100) according to one of claims 1 to 9, which is designed as a composite pane, wherein the glass panes (1, 6) are connected via a thermoplastic intermediate layer (7).

11. Device (200) with thermal stabilization of at least one hologram element (2), comprising the pane (100) according to one of claims 1 to 10, a dashboard (9), and an HVAC system (10), wherein the HVAC system (10) comprises at least one nozzle (11) arranged in the dashboard (9) with a nozzle opening (12), wherein the nozzle opening (12) is aligned with the at least one hologram element (2) and the nozzle (11) with the nozzle opening (12) is a temperature stabilization element.

12. Device (200) according to claim 11, wherein the pane (100) comprises an IR thermometer (13) as a temperature sensor, which is arranged in the dashboard (9) and is aligned with the at least one hologram element (2).

13. Method for thermal stabilization of at least one hologram element (2), wherein the at least one hologram element (2) is arranged in the pane (100) according to a of claims 1 to 10 or in the device (200) according to claim 11 or 12, at least comprising the steps: (a) providing the disc (100) or the device (200), and (b) Stabilizing the temperature of the at least one hologram element (2) to the target temperature with the at least two temperature stabilizing elements (3, 8, 11).

14. The method according to claim 13, wherein step (b) comprises at least the following steps in the order: (i) measuring the temperature of the at least one hologram element (2) with the Temperature sensor (4, 13), (ii) comparing the measured temperature with the target temperature, and (iii) optionally heating or cooling the at least one hologram element (2) with the at least two temperature stabilizing elements (3, 11) if the measured temperature deviates from the target temperature.

15. Use of the pane (100) according to one of claims 1 to 10 as a projection surface for a head-up display.

Images