WO2023179985A1

WO2023179985A1 - Operating element having a holographic functional display for visualising the switching function associated with the operating element and/or the switching state thereof, associated assembly, and associated joining method

Info

Publication number: WO2023179985A1
Application number: PCT/EP2023/054048
Authority: WO
Inventors: Björn Morber; Kilian Memmel
Original assignee: Preh Gmbh
Priority date: 2022-03-23
Filing date: 2023-02-17
Publication date: 2023-09-28
Also published as: DE102022106819A1

Abstract

The invention relates to an assembly (10) composed of a light guide (4) and a two-dimensional holographic image carrier (8) which contains a hologram and is positioned with a first main surface (H') of its two main surfaces (H, H') adjacent to the light guide (4), wherein the holographic image carrier (8) has a layer structure which has at least one photopolymer layer (8a) and an outer protective layer (8c) that forms the second main surface (H) of the holographic image carrier (8) and faces away from the light guide (4); wherein the operating element (1) also has an edge seal (9) which extends along the end faces of the holographic image carrier (8), encloses at least the photopolymer layer (8a), and is bonded integrally and/or in one piece to the outer protective layer (8c) and the light guide (4). The invention also relates to: an operating element (1) that contains the assembly (10); and an associated joining method.

Description

Control element with holographic function display for visualizing the switching function assigned to the control element and/or its respective switching status, associated arrangement and associated joining process

The invention relates to a control element with a holographic function display. Function displays are required, for example, for a multifunctional control element to visualize the switching functionalities and/or switching states associated with the control element. Electronic pixel matrix displays are regularly used for this purpose. However, these are comparatively expensive and limit the design and placement due to their mostly rectangular shape. In addition, electronic pixel matrix displays often tend to "burn in" when displaying static display content, i.e. the display content remains permanently and undesirably visible even when the display is switched off due to visually perceptible damage to the imaging layers of the display. In addition, the power consumption of such electronic pixel matrix displays is comparatively high. In certain applications, the use of conventional electronic pixel matrix displays is also prohibited due to the risk of injury, for example in the event of a head impact. Holographic image carriers are therefore an alternative to pixel matrix displays, as they allow image information to be stored in a highly integrative form in an image carrier, which can be a film or a film layer structure can, record and selectively make the image information contained therein visible to the viewer by appropriate lighting. The German patent application DE 10 2016 117 969 A1 describes devices in which luminous signatures, in particular so-called volume holograms, are generated using holographic image carriers. This describes the use of holographic image carriers containing both reflection holograms and transmission holograms. In transmission holograms, the illumination of the hologram occurs from one half-space of the hologram (i.e., from one side of the hologram), and viewing occurs from the other half-space (the other side of the hologram). With reflection holograms, however, the illumination occurs from the same side as the viewing area. When producing such control elements, the task is to fix the holographic image carrier on the surface of a light guide, which is usually made of a transparent thermoplastic, so that light from the interior of the light guide is coupled into the holographic image carrier. As mentioned above, the image information of the holographic image carrier is contained in one or more layers of photopolymers. The photopolymer layer is laminated in for mechanical stabilization. Lamination usually requires two layers of thermoplastic polymers, such as polyvinyl butyral, between which the photopolymer layer is arranged. These thermoplastic polymers often contain plasticizers or other compounds that can diffuse into the photopolymer layer, but moisture penetration can also be a problem. This can lead to swelling or shrinking of the photopolymer layer, which has adverse effects on the holographic image information. This effect is particularly strong if the holographic image information is already contained in the photopolymer layer before lamination. This means that after lamination the hologram is no longer visible under the same conditions (the same laser) as intended when generating the holographic image information. A further layer can be arranged between the photopolymer layer and the thermoplastic intermediate layers, which serves to protect the photopolymer layer. The adhesion between these two layers is often not particularly good. This can lead to delamination, i.e. detachment of the layers of the layer structure, which makes the holographic image carrier unusable.

Against this background, the object of the present invention is to provide a control element with an arrangement of a light guide and a holographic image carrier realized in a layered structure, the durability of which is increased, and at the same time its technical advantages, such as a small construction volume with a comparatively high image information density for a control element to make it permanently usable for visualizing the switching function assigned to the control element and/or its respective switching state, with the visualization not being affected by dirt or haptic elements on the surface. This task is achieved by a control element of claim 1, the arrangement and the joining method of each secondary claims solved. Advantageous refinements are the subject of the respective dependent claims. It should be noted that the features listed individually in the patent claims can be combined with one another in any technologically sensible manner and show further refinements of the invention. The description, particularly in connection with the figures, additionally characterizes and specifies the invention.

The invention relates to an operating element with an input part that forms an input surface that is at least partially transparent or at least partially translucent. It also has a carrier for fixing the control element to an external structure, in particular a motor vehicle component, such as a dashboard, a center console, a steering wheel or the like. According to the invention, a detection device is provided which is designed to detect an actuation and/or a touch of the input surface by an operator. An actuation is understood to mean a displacement of the input surface that goes beyond touching the input surface and follows an actuating force acting on the input surface during the actuation. Accordingly, in the case of a touch, for example, the degree of approach to the input surface will be decisive for the positive detection of a touch, while in the case of an actuation, the measured displacement or the measured actuation force, for example, are the decisive variables for the positive detection of an actuation.

According to the invention, from the operator's perspective, a transparent light guide is provided which is arranged below the input surface and is fixed to the carrier and has an upper boundary surface facing the input surface and a lower boundary surface facing away from the input surface. The light guide is, for example, made of a transparent thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile butadiene styrene (ABS) or polymethyl methacrylate (PMMA). For example, the light guide is produced in a thermal shaping process, for example as an injection molding or by thermal extrusion, for example as a film. Preferably, the upper boundary surface and the lower boundary surface are at least partially or completely aligned parallel to one another. According to the invention, at least one light source is provided, which is aligned such that an optical reproduction wave field is coupled into the light guide via a light entry surface.

According to the invention, a holographic image carrier containing a hologram is provided, which is arranged adjacent to one of the interfaces made up of the upper and lower interfaces. The holographic image carrier is preferably arranged adjacent to the interface of the light guide facing the input surface. The playback wave field coupled into the light guide and generated by the light source passes from the light entry surface due to light propagation caused by internal reflections, preferably total reflections, in the light guide into the holographic image carrier, and is there preferably through phase and / or amplitude interference from the playback wave field into the hologram transformed as an image wave field containing image information, which is coupled out of the holographic image carrier in order to reach the operator, if necessary via the light guide. The light path of the image wave field depends not only on the arrangement of the holographic image carrier but also on its design, whether it contains a transmission hologram or a reflection hologram. If the image wave field reaches the viewer, it can make a virtual or real image visible to the viewer. The hologram visually symbolizes a switching functionality assigned to the control element and/or an acute switching state. The holographic image carrier has a layer structure that has at least one photopolymer layer containing the hologram. For example, it is a layer that interferes with the playback wave field and is capable of impressing the image information contained in the layer on the reflected image wave field by means of phase modulation and/or amplitude modulation through locally selective diffraction interference of the playback wave field. For example, the thickness of the photopolymer layer is in the range from 1 pm to 70 pm. The holographic image information is introduced into it, for example, by embossing.

The term optical reproduction wave field is intended to express that the light to be used must be adjusted to the respective holographic image carrier in a suitable manner for the reproduction of the hologram, for example in terms of spectral composition and angle of incidence, since it is a prerequisite inherent in the holographic image carrier for the visualization of the hologram it contains and its optical quality. It is therefore the responsibility of the specialist to take the necessary measures. By implementing the optical display according to the invention by means of an arrangement containing a light guide and a holographic image carrier, a control element with an associated function display can be implemented in a space-saving manner, which selectively displays at least one symbol by activating a light source. The “optical separation” of the light guide and the input surface also ensures that the optical system for generating the virtual image is not impaired by dirt and/or haptic elements on the input surface. The complete image information can be integrated into the first holographic image carrier and remains The transparent input surface makes it reliably invisible to the operator, even when exposed to external light, so that incorrect information can be largely avoided.

In order to avoid damage to the comparatively sensitive photopolymer layer due to the indiffusion of foreign substances and moisture, the one or more photopolymer layers are encapsulated according to the invention: While the holographic image carrier is arranged with a first of its two main surfaces adjacent to the light guide, it is further provided that in that the holographic image carrier formed by the layer structure has, in addition to the one or more photopolymer layers containing the hologram, an outer protective layer which forms the second of the two main surfaces of the holographic image carrier, facing away from the light guide, in order to cover the at least one photopolymer layer. According to the invention, an edge seal extending along the end faces of the holographic image carrier and enclosing at least one photopolymer layer is also provided, which is cohesively and/or integrally connected to the protective layer and the light guide. The main surfaces are those surfaces with the largest surface area of the holographic image carrier, while the end faces of the flat, holographic image carrier are the narrow sides connecting the two main surfaces. A protective layer is understood, for example, to be a layer for protecting the photopolymer layer from mechanical damage. The Edge sealing due to the cohesive connection and/or integrality with the outer protective layer and with the light guide prevents the edge detachment of the layers of the layer structure mentioned at the beginning.

The holographic image carrier and the light guide are preferably connected in a materially bonded manner. For example, the cohesive connection is achieved in that the holographic image carrier has an adhesive layer, preferably a transparently hardening adhesive layer, which is arranged so that it forms the second main surface of the holographic image carrier facing the light guide.

The edge seal is preferably formed by the outer protective layer.

The outer protective layer is preferably a transparent plastic film, such as a thermoplastic plastic film. Such films can be manufactured precisely and only have minimal contamination, so that visual impairments can be avoided.

The outer protective layer preferably has at least predominantly polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC). More preferably, the outer protective layer is made of polyethylene terephthalate (PET). Such layers serve as a vapor barrier.

Preferably, the at least one photopolymer layer is arranged between a protective layer forming the second main surface and an inner protective layer closer to the first main surface, the inner protective layer being predominantly polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC). More preferably, the inner protective layer is made of polyethylene terephthalate (PET). Such layers serve as a vapor barrier.

Between the light guide and the photopolymer layer closest to it, there is preferably at least one inner separating layer made predominantly of polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), Polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC), more preferably polycarbonate (PC), which acts as a diffusion barrier, for example for plasticizers of the light guide.

Preferably, there is at least one outer separating layer made predominantly of polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) between the outer protective layer forming the second main surface and the photopolymer layer closest to it ) or cellulose triacetate (TAC), preferably polycarbonate (PC), which acts as an additional diffusion barrier.

In one embodiment, the outer protective layer is a scratch-resistant coating of a polysiloxane, which results in a so-called hard coating.

In another embodiment, the edge seal is formed by an adhesive or varnish, for example a transparent-curing adhesive or UV-curing varnish. For example, the edge seal is formed by the adhesive of that adhesive layer of the holographic image carrier which is intended for the material bonding of the holographic image carrier. For example, the edge seal is formed by excess adhesive escaping from under the layer structure on the end faces before it hardens. For example, it is an optically transparent liquid adhesive that hardens.

It is preferably provided that the edge seal covers the second main surface formed by the outer protective layer exclusively in an edge region; it is preferably provided that the edge seal does not cover the second main surface and, for example, only touches the outer protective layer in the area of the end face of the outer protective layer. More preferably, it is provided that the coverage of the second main surface by the edge seal is selected so that the visualization of the hologram is unimpaired, because, for example, the edge seal does not cover the hologram contained in the photopolymer layer from the viewer's perspective. Most preferably it is provided that the second main surface has a maximum 1 mm starting from its outermost edge is covered.

In another embodiment, the edge seal and the outer protective layer are formed by an adhesive or a varnish, so that the edge seal and the outer protective layer are made in one piece.

The light guide preferably has a depression in which the holographic image carrier is arranged. This ensures that the edge seal is reliably formed during paint or adhesive application.

According to a preferred embodiment, an air gap is provided between the first holographic image carrier and the input part. According to a preferred embodiment, the input part is designed to be elastically deformable in the direction of the light guide under the action of an actuating force on the input surface or is mounted in an elastically restoring manner relative to the carrier in the direction of the light guide in order to enable detectable actuation of the input surface, and at least in the area below the Input surface preferably the aforementioned air gap is provided between the holographic image carrier and the input part. The protective layer of the holographic image carrier has the advantage that mechanical damage to the photopolymer layer containing the hologram can be ruled out. For example, the input part is made of an elastically yielding material, such as a thermoplastic or an elastomer, at least in the area surrounding the input surface. In one embodiment, a restoring displacement results from a spring-loaded translational mounting of the input part on the carrier.

Preferably, the input part can be deformed and/or displaced independently of the light guide, for example by only fastening or mounting the input part on the carrier. This means that the optical system is not affected when actuated.

An actuation sensor, for example a force sensor or a mechanical switch, is preferably located between the input part and the carrier. This is preferably arranged so that the flow of force exerted during an actuation of the input surface to the force sensor does not go over the light guide.

In a preferred embodiment of the control element, an optical element, such as a mirror or a lens, is provided for generating a collimated reproduction wave field; for example, the light entry surface is designed as an optical element. More preferably, one or more optical elements are arranged between the light entry surface of the light guide and the light source in order to improve the display quality of the hologram.

The light guide is preferably designed to be essentially flat, with the upper boundary surface and the lower boundary surface each forming a main surface and an end face connecting the main surfaces forming the light entry surface of the light guide. Here too, the largest areas of the light guide are understood to be the main areas. The main surfaces of the light guide are preferably flat and aligned parallel to one another.

Preferably, a main direction of propagation of the light source is aligned inclined to the upper boundary surface.

Preferably, the light entry surface, viewed from the operator, is arranged laterally and/or rearwardly offset with respect to the holographic image carrier.

To improve the transmission of the playback wave field, the light guide has a cross-sectional expansion along its course; in particular, cross-sectional expansion is provided where a change in direction in the light propagation is required.

According to a preferred embodiment, the light guide has a first light guide section having the light entry surface and a second light guide section having the upper interface and lower interface, which merge into one another in a transition section, and wherein the first light guide section, the second light guide section and the transition section are designed in this way that the light entry surface is arranged offset backwards from the lower boundary surface from the viewer's perspective. For example, a cross section which is orthogonal to the upper boundary surface and orthogonal to the light entry surface Light guide is essentially L-shaped, with the first light guide section and the second light guide section each forming a leg of the “L”. Preferably, the transition section forms the aforementioned cross-sectional expansion.

Preferably, the transition section has at least one reflection surface inclined to the upper boundary surface in order to reflect the optical reproduction wave field from the first light guide section into the second light guide section by internal reflection on the reflection surface.

The input part is preferably connected to the carrier and/or the light guide in a materially bonded manner, for example by ultrasonic welding. By welding using ultrasound, a clear dimension between the input part and the light guide, for example an air gap, can be produced with a small dimension and precise alignment. The clear dimension between the light guide and the input part is preferably smaller than 1mm, preferably smaller than 0.5mm.

Due to the very stable and permanent fastening in this embodiment, it is possible for the light guide to be mechanically displaced along with the input part when actuated. In this case, the light source is preferably also attached to the input part, which in turn is mounted on the carrier.

The control element preferably has a transparent electrode or a transparent electrode array, which are each fixed to the input part in the area of the input surface. The control element also has an evaluation unit that is electrically conductively connected to the electrode or electrodes of the electrode array for capacitive, preferably spatially resolved, touch detection. For actuation detection, an electromechanical switching element or a force sensor, such as a capacitive force sensor, can be provided, which are arranged, for example, between the carrier and the input part.

The invention further relates to an arrangement consisting of a light guide and a flat, holographic image carrier containing a hologram, which is arranged with a first of its two main surfaces adjacent to the light guide. The holographic image carrier has a layer structure that has at least one photopolymer layer containing a hologram. It is preferred about a transfer hologram.

In order to avoid damage to the comparatively sensitive photopolymer layer due to the indiffusion of foreign substances and moisture, the one or more photopolymer layers are encapsulated according to the invention: while the holographic image carrier is arranged with a first of its two main surfaces adjacent to the light guide, it is also provided in that the holographic image carrier formed by the layer structure has, in addition to the one or more photopolymer layers containing the hologram, an outer protective layer which forms the second of the two main surfaces of the holographic image carrier, facing away from the light guide, in order to cover the at least one photopolymer layer. According to the invention, an edge seal extending along the end faces of the holographic image carrier and enclosing at least one photopolymer layer is also provided, which is cohesively and/or integrally connected to the protective layer and the light guide. The main surfaces are those surfaces with the largest surface area of the holographic image carrier, while the end faces of the flat, holographic image carrier are the narrow sides connecting the two main surfaces. A protective layer is understood, for example, to be a layer for protecting the photopolymer layer from mechanical damage. The edge sealing due to the cohesive connection and/or integrality with the outer protective layer and with the light guide prevents the edge detachment of the layers of the layer structure mentioned at the beginning.

The edge seal is preferably formed by the outer protective layer.

The outer protective layer is preferably a transparent plastic film, such as a thermoplastic plastic film. Such films can be manufactured precisely and have at most minor impurities so that visual impairments can be avoided.

The at least one photopolymer layer is preferably arranged between an outer protective layer forming the second main surface and an inner protective layer closer to the first main surface, the inner protective layer being predominantly polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), Polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC). More preferably, the inner protective layer is made of polyethylene terephthalate (PET). Such layers serve as a vapor barrier.

Preferably there is at least one inner separating layer made predominantly of polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC) between the light guide and the photopolymer layer next to it. , preferably polycarbonate (PC), which acts as a diffusion barrier, for example for plasticizers of the light guide.

Preferably, between the outer protective layer and the next adjacent photopolymer layer is at least one outer separating layer made predominantly of polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC). ), preferably polycarbonate (PC), which acts as an additional diffusion barrier.

In one embodiment, the outer protective layer is a scratch-resistant coating of a polysiloxane, which results in a so-called hard coating. In another embodiment, at least the edge seal is formed by an adhesive or varnish, for example a transparent-curing adhesive or UV-curing varnish. For example, the edge seal is formed by the adhesive of that adhesive layer of the holographic image carrier which is intended for the material bonding of the holographic image carrier. For example, the edge seal is formed by excess adhesive escaping from under the layer structure on the end faces before it hardens. For example, it is an optically transparent liquid adhesive that hardens.

It is preferably provided that the edge seal covers the second main surface formed by the outer protective layer exclusively in an edge region; it is preferably provided that the edge seal does not cover the second main surface and, for example, only touches the outer protective layer in the area of the end face of the outer protective layer. More preferably, it is provided that the coverage of the second main surface by the edge seal is selected so that the visualization of the hologram is unimpaired, because, for example, the edge seal does not cover the hologram contained in the photopolymer layer from the viewer's perspective. Most preferably it is provided that the second main surface is covered by a maximum of 1 mm from its outermost edge.

The invention further relates to a method for joining a holographic image carrier and a light guide. In a provision step, a light guide is provided. This is made, for example, in an upstream thermal shaping process step from one made of transparent thermoplastic.

In a subsequent step, a flat, holographic image carrier containing a hologram is fastened over the entire surface to a surface of the light guide, with the holographic image carrier being arranged with a first of its two main surfaces adjacent to the light guide. The cohesive connection is preferably carried out using a transparent adhesive, which is applied as a liquid adhesive to the light guide and/or the holographic image carrier in order to form an adhesive layer of the holographic image carrier after its crosslinking or hardening. The holographic image carrier has a layer structure which has at least one photopolymer layer containing the hologram and an outer protective layer which forms the second main surface of the holographic image carrier facing away from the light guide. In one embodiment, the protective layer is applied to the photopolymer layer before the joining layer; alternatively, the outer protective layer can be applied following the joining step.

Preferably, the at least one photopolymer layer is arranged between an outer protective layer forming the second main surface and an inner protective layer closer to the first main surface, the inner protective layer being predominantly polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC). , polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC). This is more preferred Another protective layer made of polyethylene terephthalate (PET). Such layers serve as a vapor barrier.

Preferably, between the outer protective layer and the next adjacent photopolymer layer is at least one outer separating layer made predominantly of polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC). ), preferably polycarbonate (PC), which acts as a further diffusion barrier.

The method according to the invention comprises a step of producing an edge seal which extends along the end faces of the holographic image carrier and encloses at least the photopolymer layer, which is cohesively and/or integrally connected to the outer protective layer and the light guide.

The edge seal is preferably formed by the adhesive of that adhesive layer of the holographic image carrier which is formed when the light guide and the holographic image carrier are joined, for example by excess liquid adhesive emerging from the end faces forming the edge seal after curing or crosslinking. It is preferably provided that the edge seal covers the second main surface formed by the outer protective layer exclusively in an edge region; it is preferably provided that the edge seal does not cover the second main surface and, for example, only touches the outer protective layer in the area of the end face of the outer protective layer. More preferably, it is provided that the coverage of the second main surface by the edge seal is selected so that the visualization of the hologram is unimpaired because For example, from the viewer's perspective, the edge seal does not cover the hologram contained in the photopolymer layer. Most preferably it is provided that the second main surface is covered by a maximum of 1 mm from its outermost edge.

According to an alternative embodiment, the edge seal is created during the application of the outer protective layer applied using the dipping process and/or spin coating process, for example by flowable material that flows over forming the edge seal following its gravity and/or capillary or adhesion forces before it hardens or crosslinks.

According to a further embodiment, the edge seal is applied by applying an associated material from a dosing head, preferably during motor-driven relative adjustment between the light guide and the dosing head. It is preferably provided that the edge seal covers the second main surface formed by the outer protective layer exclusively in an edge region; it is preferably provided that the edge seal does not cover the second main surface and, for example, only touches the outer protective layer in the area of the end face of the outer protective layer. More preferably, it is provided that the coverage of the second main surface by the edge seal is selected so that the visualization of the hologram is unimpaired, because, for example, the edge seal does not cover the hologram contained in the photopolymer layer from the viewer's perspective. Most preferably it is provided that the second main surface is covered by a maximum of 1 mm from its outermost edge.

According to a further embodiment of the method, the edge seal is produced by ultrasonic welding of the outer protective layer, preferably produced from a thermoplastic, to the light guide, more preferably produced from the ultrasonic welding of the outer protective layer and inner protective layer and light guide.

The invention and the technical environment are explained in more detail below using the figures. It should be noted that the figures are special show preferred embodiment variant of the invention, but this is not limited to it. It shows schematically:

Figure 1 is a schematic sectional view of an embodiment of the control element 1 according to the invention;

Figure 2 shows a schematic sectional view of a first embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and to explain a first embodiment of the joining method according to the invention;

Figure 3 shows a schematic sectional view of a second embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and to explain a second embodiment of the joining method according to the invention;

Figure 4 shows a schematic sectional view of a third embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and to explain a third embodiment of the joining method according to the invention;

Figure 5 shows a schematic sectional view of a fourth embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and to explain a fourth embodiment of the joining method according to the invention;

Figure 6 shows a schematic sectional view to explain a fifth embodiment of the joining method according to the invention;

Figure 7 is a schematic sectional view to explain a sixth embodiment of the joining method according to the invention.

Figure 1 shows an embodiment of the control element 1. The control element 1 has an input part 2 made of a thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile-butadiene Styrene (ABS) or polymethyl methacrylate (PMMA). The control element 1 has a transparent input surface 3 formed by a control part 2, which is at the same time a display surface for the symbol visible underneath, which, as described below, is activated when one of the control elements 1 is activated assigned light source 5 becomes visible to operator B. The input surface 3 has elevations 14 arranged in the input surface 3 and/or surrounding the respective input surface 3 as haptic orientation aids. It also has a respective carrier 12 for fixing the control element 1 to an external structure, not shown, in particular a motor vehicle component, such as a dashboard, a center console, a steering wheel or the like. In the embodiment shown, the input part 2 is mounted on the carrier 12 in a translationally displaceable manner in a direction Actuating force causes a displacement of the input surface 3 following the actuating force against a restoring force in the direction of the light guide 4, for example caused by an electromechanical switching element or a return spring.

The control element 1 has a detection device 13, which is designed here to detect a touch of the input surface 3 by the operator B. For this purpose, the detection device 13 used in the fourth embodiment of the control element 1 has a transparent electrode array which is fixed on the side of the input part 2 facing away from the operator B under the input surface 3 on the input part 2 in order to achieve spatially resolved, capacitive proximity detection by means of an evaluation unit (not shown). to carry out in order to capacitively detect the location and the extent of an approach to the input surface 3 and then positively detect a touch of the corresponding input surface 3 when a predetermined approach dimension is exceeded and a corresponding touch location is detected.

As can be seen from Figure 1, a transparent light guide 4 is provided in the control element 1, which is arranged below the input surface 3 from the perspective of the operator B and is fixed to the carrier 12 and has an upper boundary surface G and facing the input surface 3 or the operator B has a lower boundary surface G' facing away from the input surface 3 or the operator B. An air gap 15 is provided between the upper boundary surface and the area of the input part 2 provided with the input surface 3, which also extends over the flat holographic image carrier 8 extends.

The light guide 4 is, for example, made of a transparent thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile butadiene styrene (ABS) or polymethyl methacrylate (PMMA). . For example, the light guide 4 is manufactured in one piece or in several parts in a thermal shaping process, for example as an injection molding.

The control element 1 has a light source 5, here in the form of a light-emitting diode designed in SMD construction, which is soldered to a circuit board 11 fixed to the carrier 12. The light source 5 is directed with its main radiation direction H towards the light entry surface S in such a way that the main radiation direction H is perpendicular to the upper boundary surface G and an optical reproduction wave field L is coupled into the light guide 4 via the light entry surface S. To generate a playback wave field L containing collimated light, an optical element 7 is provided between the light entry surface S of the light guide 4 and the light source 5. The optical element 7 is, for example, formed in one piece with the light guide 4. For example, it is part of the interface of the light guide 4 that forms the light entry surface S.

The control element 1 has a holographic image carrier 8 containing a transmission hologram, which is arranged adjacent to the upper boundary surface G of the light guide 4.

The light guide 4 has a first light guide section 4′ having the light entry surface S, a second light guide section 4″ having the upper interface G and lower interface G′, and a transition section 4″ connecting the first and second light guide sections. The first light guide section 4', the second light guide section 4" and the transition section 4"' are designed in such a way that the light entry surface S, from the perspective of the observer B, is offset backwards and laterally to the upper boundary surface G and thus to the one adjacent to the upper boundary surface G , holographic image carrier 8 is arranged. As shown, a cross section of the light guide 4 is essentially orthogonal to the upper boundary surface G and orthogonal to the light entry surface S L-shaped, with the first light guide section 4 'and the second light guide section 4" each forming one leg of the "L". The transition section 4''' forms a cross-sectional expansion of the light guide 4 along its course through a wedge-shaped extension piece in order to enable the change of direction in the light propagation from the first light guide section 4' to the second light guide section 4'' with the lowest possible losses.

In order to effect the change of direction, the transition section 4"' forms a reflection surface R inclined to the upper boundary surface G in order to reflect the optical reproduction wave field L from the first light guide section 4' into the second light guide section 4" by internal reflection on the reflection surface R.

The reproduction wave field L coupled into the light guide 4 and generated by the light source 5 reaches the first holographic image carrier 8 from the light entry surface S due to light propagation caused by total reflections in the light guide 4, among other things at the reflection surface R, and is preferred there through phase and/or amplitude interference from the playback wave field L into an image wave field L 'containing the first transmission hologram as image information. The image wave field L 'is coupled out of the holographic image carrier 8 in the direction of the operator B in order to display the transmission hologram stored in the holographic image carrier 8 to the operator B as a virtual image, for example a symbol. The first transmission hologram visually symbolizes a switching functionality assigned to the respective control element 1 and/or an acute switching state.

The holographic image carrier 8 is designed as a transparent layer structure and has at least one photopolymer layer 8a containing the transmission hologram, an adhesive layer 8b and a protective layer 8c, which is, for example, a PET layer, a scratch-resistant coating of a polysiloxane, an adhesive layer or a lacquer layer. The transparent protective layer 8c is an outer layer of the holographic image carrier 8 formed in the layer structure and forms a second, here upper main surface H of the holographic image carrier 8, facing away from the light guide 4. For example, the thickness of the photopolymer layer is in the range from 1 pm to 70 pm. The holographic one Image information is incorporated into it, for example, by embossing. The holographic image carrier 8 and the light guide 4 are cohesively connected via the transparent adhesive layer 8b of the holographic image carrier 8, which forms the first main surface H with which the holographic image carrier 8 adjoins the light guide 4. In addition, an edge seal 9 extending along the end faces of the holographic image carrier 8 and enclosing a photopolymer layer 8a is also provided, which is cohesively or integrally connected to the protective layer 8c and to the light guide 4. The main surfaces H, H' are those surfaces with the largest surface area of the holographic image carrier 8, while the end faces of the flat, holographic image carrier 8 are the narrow sides connecting the two main surfaces H, H'. The protective layer 8c is understood, for example, to be a layer for protecting the photopolymer layer 8a from mechanical damage. The edge seal 9 due to the cohesive connection and/or integrality with the protective layer 8c and with the light guide 4 prevents the initially mentioned edge detachment of the layers of the layer structure of the holographic image carrier 8.

Figure 2 shows a first embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and also serves to explain a first embodiment of the joining method according to the invention. The light guide 4 is, for example, made of a transparent thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile butadiene styrene (ABS) or polymethyl methacrylate (PMMA). . For example, the light guide 4 is manufactured in one piece or in several parts in a thermal shaping process, for example as an injection molding.

The arrangement 10 has a holographic image carrier 8 containing a transmission hologram, which is arranged with its first main surface H 'adjacent to an interface of the light guide 4, while its second main surface H faces away from the light guide.

The light guide 4 serves to guide light from a light entry surface S of the light guide to that applied to an interface of the light guide 4 holographic image carrier 8 through internal reflections, in particular total reflections, at the interfaces of the light guide 4.

The light guide 4 has a first light guide section 4' which has the light entry surface S, a second light guide section 4" which carries the holographic image carrier 8, and a transition section 4"' which connects the first and second light guide sections. The first light guide section 4', the second light guide section 4" and the transition section 4'" are designed such that the light entry surface S is arranged away from the holographic image carrier 8. As shown, a cross section of the light guide 4 which is orthogonal to the first main surface H' of the holographic image carrier 8 and to the light entry surface S is essentially L-shaped, with the first light guide section 4' and the second light guide section 4" each forming one leg of the "L". The transition section 4"' forms a cross-sectional expansion of the light guide 4 along its course through a wedge-shaped extension piece, in order to enable the change of direction in the light propagation from the first light guide section 4' to the second light guide section 4" with the lowest possible losses.

In order to effect the change of direction, the transition section 4'" forms an inner reflection surface R inclined to the first main surface H' in order to reflect the optical reproduction wave field from the first light guide section 4' into the second light guide section 4" by internal reflection on the reflection surface .

The playback wave field coupled into the light guide 4 passes from the light entry surface S due to light propagation caused by total reflections in the light guide 4, including at the reflection surface R, into the first holographic image carrier 8, and is there preferably through phase and / or amplitude interference from the playback wave field into the first Transmission hologram transformed as an image wave field containing image information. The image wave field is coupled out of the holographic image carrier 8, for example in the direction of an operator, in order to display the transmission hologram stored in the holographic image carrier 8 as a virtual image, for example a symbol. The holographic image carrier 8 is designed as a transparent layer structure and has a photopolymer layer 8a containing the transmission hologram, an adhesive layer 8b and a protective layer 8c, which here is a UV-curing transparent lacquer layer. The transparent protective layer 8c is an outer layer of the holographic image carrier 8 formed in the layer structure and forms a second, here upper main surface H of the holographic image carrier 8, facing away from the light guide 4. For example, the thickness of the photopolymer layer is in the range of 1 pm to 70 pm, such as 20 pm. The holographic image information is incorporated into it, for example, by embossing. The holographic image carrier 8 and the light guide 4 are materially connected via the transparent adhesive layer 8b of the holographic image carrier 8, which, for example, has a thickness of 50 to 100 pm, which forms the first main surface H ', with which the holographic image carrier 8 is attached to the light guide 4 adjacent.

Between the light guide 4 and the photopolymer layer 8a, an inner separating layer 8d' made essentially of polycarbonate (PC) is provided, which acts as a diffusion barrier, for example for plasticizers of the light guide, and has a thickness of approximately 150 mm. Furthermore, between the protective layer 8c and the photopolymer layer 8a there is an outer separating layer 8d, also made essentially of polycarbonate (PC), which acts as an additional diffusion barrier, for example for the plasticizers from the outer protective layer 8c.

In addition, an edge seal 9 extending along the end faces of the holographic image carrier 8 and enclosing a photopolymer layer 8a is also provided, which is cohesively connected to the outer protective layer 8c and to the light guide 4 and is formed by a hardening or crosslinked liquid adhesive, which was applied by a movable dosing head 30. The main surfaces H, H' are those surfaces with the largest surface area of the holographic image carrier 8, while the end faces of the flat, holographic image carrier 8 are the narrow sides connecting the two main surfaces H, H'. The edge seal 9 prevents the initially mentioned edge detachment of the layers of the layer structure of the holographic image carrier 8 due to the cohesive connection with the protective layer 8c and with the light guide 4. Figure 3 shows a second embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and also serves to explain a second embodiment of the joining method according to the invention. The light guide 4 is, for example, made of a transparent thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile butadiene styrene (ABS) or polymethyl methacrylate (PMMA). . For example, the light guide 4 is manufactured in one piece or in several parts in a thermal shaping process, for example as an injection molding.

The arrangement 10 has a holographic image carrier 8 containing a transmission hologram, which is arranged with its first main surface H 'adjacent to an interface of the light guide 4, while its second main surface H faces away from the light guide 4.

The light guide 4 serves to guide light from a light entry surface S of the light guide to the holographic image carrier 8 applied to an interface of the light guide 4 through internal reflections, in particular total reflections, at the interfaces of the light guide 4.

In order to effect the change of direction, the transition section 4'" forms a the first main surface H' inclined, inner reflection surface R in order to reflect the optical reproduction wave field from the first light guide section 4' into the second light guide section 4" by internal reflection on the reflection surface.

The playback wave field coupled into the light guide 4 passes from the light entry surface S due to light propagation caused by total reflections in the light guide 4, among other things at the reflection surface R, into the first holographic image carrier 8, and is there preferably through phase and / or amplitude interference from the playback wave field into the first Transmission hologram transformed as an image wave field containing image information. The image wave field is coupled out of the holographic image carrier 8, for example in the direction of an operator, in order to display the transmission hologram stored in the holographic image carrier 8 as a virtual image, for example a symbol.

The holographic image carrier 8 is designed as a transparent layer structure and has a photopolymer layer 8a containing the transmission hologram, an adhesive layer 8b and an outer protective layer 8c, which here is a layer made essentially of polyethylene terephthalate (PET). The transparent protective layer 8c is an outer layer of the holographic image carrier 8 formed in the layer structure and forms a second, here upper main surface H of the holographic image carrier 8, facing away from the light guide 4. For example, the thickness of the photopolymer layer 8a is in the range of 1 pm to 70 pm, such as 20 pm. The holographic image information is incorporated into it, for example, by embossing. The holographic image carrier 8 and the light guide 4 are materially connected via the transparent adhesive layer 8b of the holographic image carrier 8, which, for example, has a thickness of 50 to 100 pm, which forms the first main surface H ', with which the holographic image carrier 8 is attached to the light guide 4 adjacent.

Between the light guide 4 and the photopolymer layer 8a there is an inner separating layer 8d' made essentially of polycarbonate (PC), which acts as a diffusion barrier, for example against plasticizers of the light guide 4, and has a thickness of approximately 150 mm. Furthermore, between the outer Protective layer 8c and the photopolymer layer 8a have an outer separating layer 8d made essentially of polycarbonate (PC), which acts as an additional diffusion barrier, for example against plasticizers from the outer protective layer 8c.

Between the inner separating layer 8d 'and the adhesive layer 8b is an inner protective layer 8c' made essentially of polyethylene terephthalate (PET), which seals and shields the photopolymer layer 8a in the direction of the light guide 4.

In addition, an edge seal 9 extending along the end faces of the holographic image carrier 8 and enclosing a photopolymer layer 8a is also provided, which is cohesively connected to the outer protective layer 8c and to the light guide 4 and is formed by a hardening or crosslinked liquid adhesive, which was applied by a movable dosing head 30. The main surfaces H, H' are those surfaces with the largest surface area of the holographic image carrier 8, while the end faces of the flat, holographic image carrier 8 are the narrow sides connecting the two main surfaces H, H'. The edge seal 9 due to the cohesive connection with the outer protective layer 8c and with the light guide 4 prevents the edge detachment of the layers of the layer structure of the holographic image carrier 8 mentioned at the beginning.

Figure 4 shows a third embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and also serves to explain a third embodiment of the joining method according to the invention. The light guide 4 is, for example, made of a transparent thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile butadiene styrene (ABS) or polymethyl methacrylate (PMMA). . For example, the light guide 4 is manufactured in one piece or in several parts in a thermal shaping process, for example as an injection molding.

The arrangement 10 has a holographic image carrier 8 containing a transmission hologram, which is adjacent with its first main surface H ' is arranged on an interface of the light guide 4, while its second main surface H faces away from the light guide.

In order to effect the change of direction, the transition section 4"' forms an inner reflection surface R inclined to the first main surface H' in order to supply the optical reproduction wave field from the first light guide section 4' into the second light guide section 4" by internal reflection on the reflection surface R reflect.

The playback wave field coupled into the light guide 4 passes from the light entry surface S due to light propagation caused by total reflections in the light guide 4, including at the reflection surface R, into the first holographic image carrier 8, and is there preferably through phase and / or amplitude interference from the playback wave field into the first Transmission hologram as an image wave field containing image information transformed. The image wave field is coupled out of the holographic image carrier 8, for example in the direction of an operator, in order to display the transmission hologram stored in the holographic image carrier 8 as a virtual image, for example a symbol.

The holographic image carrier 8 is designed as a transparent layer structure and has a photopolymer layer 8a containing the transmission hologram, an adhesive layer 8b and a protective layer 8c, which here is a scratch-resistant coating of a polysiloxane or a layer made essentially of polyethylene terephthalate (PET). The transparent protective layer 8c is an outer layer of the holographic image carrier 8 formed in the layer structure and forms a second, here upper main surface H of the holographic image carrier 8, facing away from the light guide 4. For example, the thickness of the photopolymer layer is in the range of 1 pm to 70 pm, such as 20 pm. The holographic image information is incorporated into it, for example, by embossing. The holographic image carrier 8 and the light guide 4 are materially connected via the transparent adhesive layer 8b of the holographic image carrier 8, which, for example, has a thickness of 50 to 100 μm. For this purpose, the light guide 4 has a depression 16 in its interface, in which the holographic image carrier 8 is arranged so that its first main surface H adjoins the light guide 4.

Between the light guide 4 and the photopolymer layer 8a there is an inner separating layer 8d' made essentially of polycarbonate (PC), which acts as a diffusion barrier, for example against plasticizers of the light guide 4, and has a thickness of approximately 150 mm. Furthermore, an outer separating layer 8d made essentially of polycarbonate (PC) is provided between the outer protective layer 8c and the photopolymer layer 8a, which acts as a diffusion barrier against plasticizers of the outer protective layer 8c.

In addition, an edge seal 9 is also provided which extends along the end faces of the holographic image carrier 8 and encloses a photopolymer layer 8a, which is materially connected to the protective layer 8c and to the light guide 4 and is formed by the adhesive of that adhesive layer 8b of the holographic image carrier 8, for the cohesive fixation of the holographic image carrier 8 on the light guide 4 is provided. The edge seal 9 is thus formed by excess adhesive escaping from under the layer structure on the end faces before it hardens. This is an optically transparent liquid adhesive that hardens.

Figure 5 shows a fourth embodiment of the arrangement 10 according to the invention consisting of a light guide 4 and a holographic image carrier 8 and also serves to explain a fourth embodiment of the joining method according to the invention. The light guide 4 is, for example, made of a transparent thermoplastic, such as polyethylene (PE), polycarbonate (PC), polystyrene (PS), polyvinyl chloride (PVC), polyamides (PA), acrylonitrile butadiene styrene (ABS) or polymethyl methacrylate (PMMA). . For example, the light guide 4 is manufactured in one piece or in several parts in a thermal shaping process, for example as an injection molding.

The light guide 4 has a first light guide section 4' which has the light entry surface S, a second light guide section 4" which carries the holographic image carrier 8, and a transition section 4"' which connects the first and second light guide sections. The first light guide section 4', the second light guide section 4" and the transition section 4"' are designed such that the light entry surface S is arranged away from the holographic image carrier 8. As shown, a cross section of the light guide 4 which is orthogonal to the first main surface H' of the holographic image carrier 8 and to the light entry surface S is essentially L-shaped, with the first light guide section 4' and the second light guide section 4" each forming one leg of the "L". Included The transition section 4"' forms a cross-sectional expansion of the light guide 4 along its course through a wedge-shaped extension piece, in order to enable the change of direction in the light propagation from the first light guide section 4' to the second light guide section 4" with the lowest possible losses.

In order to effect the change of direction, the transition section 4'" forms an inner reflection surface R inclined to the first main surface H' in order to supply the optical reproduction wave field from the first light guide section 4' into the second light guide section 4" by internal reflection on the reflection surface R reflect.

The holographic image carrier 8 is designed as a transparent layer structure and has a photopolymer layer 8a containing the transmission hologram, an adhesive layer 8b and an outer protective layer 8c, which here is a layer made essentially of polyethylene terephthalate (PET). The transparent protective layer 8c is an outer layer of the holographic image carrier 8 formed in the layer structure and forms a second, here upper main surface H of the holographic image carrier 8, facing away from the light guide 4. For example, the thickness of the photopolymer layer is in the range of 1 pm to 70 pm, such as 20 pm. The holographic image information is incorporated into it, for example, by embossing. The holographic image carrier 8 and the light guide 4 are cohesively connected via the transparent adhesive layer 8b of the holographic image carrier 8, which, for example, has a thickness of 50 to 100 pm, with its first main surface H adjoining the light guide 4. Between the light guide 4 and the photopolymer layer 8a there is an inner separating layer 8d' made essentially of polycarbonate (PC), which acts as a diffusion barrier, for example against plasticizers of the light guide 4, and has a thickness of approximately 150 mm. Furthermore, an outer separating layer 8d made essentially of polycarbonate (PC) is provided between the outer protective layer 8c and the photopolymer layer 8a, which acts as a diffusion barrier against plasticizers of the outer protective layer 8c. Furthermore, an inner protective layer 8c' is provided between the inner separating layer 8d' and the adhesive layer 8b, the inner protective layer 8c' essentially comprising polyethylene terephthalate (PET).

In addition, an edge seal 9 extending along the end faces of the holographic image carrier 8 and enclosing a photopolymer layer 8a is also provided, which is integrally or integrally connected to the outer protective layer 8c and to the inner protective layer 8c 'and is formed by ultrasonic welding with an ultrasonic knife 31 .

Based on Figures 6 and 7, methods for applying or forming the outer protective layer 8c provided in the embodiment shown in Figure 2 are outlined. 6 shows a variant of the joining method according to the invention, in which after the light guide 4 and holographic image carrier 8 have been joined, an immersion bath coating step is carried out, during which the arrangement of light guide 4 and the holographic image carrier 8 attached to it is placed in a bath 32 made of transparent curing Liquid adhesive for wetting and coating the holographic image carrier 8 is dipped. Figure 7 shows a variant of the joining method according to the invention, in which, after joining the light guide 4 and the holographic image carrier 8, an amount of the transparent curing or cross-linking adhesive or varnish intended for the formation of the protective layer 8c is applied to the outer layer of the layer structure forming the holographic image carrier 8 and is distributed while rotating the arrangement in order to form the outer protective layer 8c and optionally the edge seal 9 shown in Figure 2 after hardening.

Claims

Expectations:

1. Control element (1), comprising: an input part forming an input surface (3) that is at least partially translucent or at least partially transparent

(2); a carrier (12) for fixing the operating element to an external structure, in particular a motor vehicle component; a detection device (13, 18, 19), which is designed to actuate and/or touch the input surface

(3) to be detected by an operator (B); a transparent light guide (4), which is arranged below the input surface (3) from the operator's perspective (B) and is fixed to the carrier (12), which has an upper boundary surface (G) facing the input surface (3) and one of the input surface (3) has a lower interface (G') facing away from it; at least one light source (5) which is arranged to couple an optical reproduction wave field (L) into the light guide (4) via a light entry surface (S); a flat, holographic image carrier (8) containing a hologram, which has a first main surface (H') of its two main surfaces (H, H') adjacent to one of the two interfaces consisting of the top interface (G) or the bottom interface (G'). of the light guide (4), the reproduction wave field (L) coupled into the light guide (4) coming from the light entry surface (S) due to internal reflection in the light guide

(4) caused light propagation reaches the holographic image carrier (8), the playback wave field (L) being transformed from the holographic image carrier (8) into an image wave field (L') and the image wave field (L') emerging from the holographic image carrier (8) exits and, if necessary via the light guide (4), reaches the operator (B) in order to display the hologram stored in the holographic image carrier (8) to the operator (B) as an image, which has a switching functionality assigned to the control element (1) and / or a acute switching state is visually symbolized, the holographic image carrier (8) having a layer structure which has one or more photopolymer layers (8a) containing the hologram and an outer, second main surface (H) of the holographic image carrier (8) facing away from the light guide (4). forming protective layer (8c); wherein the control element (1) also extends along the end faces of the holographic image carrier (8). extending edge seal (9) enclosing at least the photopolymer layer (8a), which is cohesively and/or integrally connected to the outer protective layer (8c) and the light guide (4). Control element (1) according to the preceding claim, wherein the edge seal (9) is formed by the outer protective layer (8c). Control element (1) according to one of the preceding claims, wherein the outer protective layer (8c) is a plastic film, such as a thermoplastic plastic film. Control element (1) according to one of the preceding claims, wherein the outer protective layer (8c) is at least predominantly polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC), particularly preferably has polyethylene terephthalate (PET) or is a scratch-resistant coating of a polysiloxane. Control element (1) according to one of the preceding claims, wherein the edge seal (9), preferably the edge seal (9) and the outer protective layer (8c) are formed by an adhesive or varnish. Control element (1) according to one of the preceding claims, wherein the edge seal (9) covers the second main surface (H) exclusively in an edge region, preferably does not cover the second main surface (H). Control element (1) according to one of the preceding claims, wherein the light guide (4) has a depression (16) in which the holographic image carrier (8) is arranged. Control element (1) according to one of the preceding claims, wherein the holographic image carrier (8) is arranged adjacent to the upper boundary surface (G) of the light guide (4). Control element (1) according to one of the preceding claims, wherein the holographic image carrier (8) has a transparent adhesive layer (8b), via which the holographic image carrier (8) is firmly secured to the light guide (4). Control element (1) according to one of the preceding claims, wherein the hologram stored in the holographic image carrier (8) is a transfer hologram. Control element (1) according to one of the preceding claims, wherein An air gap (15) is provided between the holographic image carrier (8) and the input part (2) at least in the area below the input surface (3). Control element (1) according to one of the preceding claims, wherein the input part (2) is designed to be elastically deformable in the direction of the holographic image carrier (8) under the action of an actuating force on the input surface (3) or relative to the carrier (12) in the direction of the light guide ( 4) is mounted so that it can be moved in an elastically restoring manner in order to enable detectable actuation of the input surface (3). Control element (1) according to one of the preceding claims, wherein an optical element (7) is provided for generating a collimated reproduction wave field, which is preferably arranged between the light entry surface (S) of the light guide (4) and the light source (5). Control element (1) according to one of the preceding claims, wherein a main direction of propagation (H) of the light source (5) is aligned inclined to the upper boundary surface (G). Control element (1) according to one of the preceding claims, wherein the light guide (4) is designed such that the light entry surface (S) is arranged laterally and/or rearwardly offset relative to the first holographic image carrier (8) as seen from the operator (B). Control element (1) according to one of the preceding claims, wherein the light guide (4) has a cross-sectional expansion along its course. Control element (1) according to one of the preceding claims, wherein the light guide (4) has a first light guide section (4 ') which has the light entry surface (S) and a second light guide section (4 ') which forms the upper boundary surface (G) and lower boundary surface (G'). 4"), which merge into one another in a transition section (4"'), the first light guide section (4'), the second light guide section (4") and the transition section (4"') being designed such that the light entry surface (S ) from the viewer's perspective (B) is arranged backwards and laterally offset from the lower boundary surface (G '). Control element (1) according to the preceding claim, wherein the transition section (4"') has at least one reflection surface (R) inclined to the upper boundary surface (G) in order to reproduce the playback wave field (L). from the first light guide section (4') by internal reflection on the reflection surface (R) into the second light guide section (4"). Arrangement (10) consisting of a light guide (4) and a flat, holographic image carrier (8) containing a hologram ), which is arranged with a first main surface (H ') of its two main surfaces (H, H') adjacent to the light guide (4), the holographic image carrier (8) having a layer structure which has at least one photopolymer layer (8a) and one outer protective layer (8c), which forms the second main surface (H) of the holographic image carrier (8) facing away from the light guide (4); the control element (1) further has a protective layer (8c) which extends along the end faces of the holographic image carrier (8), at least the Edge seal (9) enclosing a photopolymer layer (8a), which is cohesively and / or integrally connected to the outer protective layer (8c) and the light guide (4). Arrangement (10) according to the preceding claim, wherein the edge seal (9) through the outer protective layer (8c) is formed. Arrangement (10) according to one of the two preceding claims, wherein the outer protective layer (8c) is a plastic film, such as a thermoplastic plastic film. Arrangement (10) according to one of the preceding claims 19 to 21, wherein the outer protective layer (8c) is at least predominantly polyethylene terephthalate (PET), polyethylene (PE), polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), polyvinyl chloride (PVC) or cellulose triacetate (TAC), particularly preferably has polyethylene terephthalate (PET) or is a scratch-resistant coating of a polysiloxane. Arrangement (10) according to one of the preceding claims 19 to 22, wherein the edge seal (9), preferably the edge seal (9) and the outer protective layer (8c) are formed by an adhesive. Arrangement (10) according to one of the preceding claims 19 to 23, wherein the edge seal (9) covers the second main surface (H) exclusively in an edge region, preferably does not cover the second main surface (H). Arrangement (10) according to one of the preceding claims 19 to 24, wherein the light guide (4) has a depression (16) in which the holographic Image carrier (8) is arranged. Arrangement (10) according to one of the preceding claims 19 to 25, wherein the holographic image carrier (8) has a transparent adhesive layer (8b) via which the holographic image carrier (8) is fixed to the light guide (4). Arrangement (10) according to one of the preceding claims 19 to 26, wherein the hologram stored in the holographic image carrier (8) is a transfer hologram. Method for joining a holographic image carrier (8) and a light guide (4);

Providing a light guide (4); cohesive, full-surface fastening of a flat, holographic image carrier (8) containing a hologram on a surface of the light guide (4), the holographic image carrier (8) having a first main surface (H') adjacent to its two main surfaces (H, H'). is arranged on the light guide (4); wherein the holographic image carrier (8) has a layer structure which has at least one photopolymer layer (8a) containing the hologram and an outer protective layer (8c) which forms the second main surface (H) of the holographic image carrier (8) facing away from the light guide (4). ;

Producing an edge seal (9) which extends along the end faces of the holographic image carrier (8) and encloses at least the photopolymer layer (8a), which is cohesively and/or integrally connected to the outer protective layer (8c) and the light guide (4). Method according to the preceding claim; wherein the edge seal (9) is created by an adhesive of an adhesive layer (8b) of the holographic image carrier (8) when joining the light guide (4) and the holographic image carrier (8). Method according to claim 28; wherein the edge seal (9) is produced during the application of the outer protective layer (8c) applied using the dipping process and/or spin coating process. Method according to claim 28; wherein the edge seal (9) is applied by applying an associated material is applied from a dosing head (30), preferably during motor-driven relative adjustment between the light guide (4) and the dosing head (30). experienced according to claim 28; wherein the edge seal (9) is produced by ultrasonic welding of the outer protective layer (8c) to the light guide (4).