Control unit for a motor vehicle with a translucent and operator-visible support body

Abstract

Control unit (1) for a motor vehicle, with a transilluminable carrier body (10), a switching arrangement (20) which is arranged on a visible surface (13) of the carrier body (10) facing an operator, and an optical transmitter (31) and an optical sensor (32) which are arranged on a rear side (R) of the carrier body (10) facing away from the operator, wherein the switching arrangement (20) has at least one switching element (21, 22) which is movable between an actuated position, in which the switching element (21, 22) rests against a contact region (11, 12) of the visible surface (13) associated with the respective switching element (21, 22), and an unactuated position, in which the respective switching element (21, 22) is spaced from the visible surface (13), so that optical reflection properties at the respective contact region (11, 12) of the visible surface (13) of the carrier body (10) can be changed depending on the position of the respective switching element (21, 22), wherein the optical transmitter (31) is designed to emit light through the carrier body (10) to the contact region (11, 12), and the optical sensor (32) is designed to detect light coupled out of the carrier body (10) and to determine therefrom the position of the at least one switching element (21, 22) and to generate a switching signal corresponding to the position.

Description

The invention relates to an operating unit for a motor vehicle having support bodies which can be illuminated and are visible to an operator.A wide variety of operating units for motor vehicles are known from the prior art, which serve to trigger or control a function of the vehicle.Starting from different requirement profiles for such operator control units, these must be adapted to their respective use or compatible for different uses.With regard to safety, it may be necessary, for example, for there to be a hermetic and / or galvanic separation between an operating element that can be actuated by the operator and the switching state detection, so that the operator cannot come into contact with current-carrying components or the switching state detection and further components cannot be damaged by penetrating liquids or particles.Furthermore, in modern motor vehicles, there are often a wide variety of equipment variants for which, however, as many identical parts as possible are to be used for cost reduction. Accordingly, it is desirable that operating units or their operating elements can be easily mounted or even retrofitted without having to store different carrier bodies for this purpose.In addition, for high-quality optics in motor vehicles, increasingly transparent components are used, in or under which, however, no electronic components are to be visible.An operating unit which fulfills at least part of these requirements is known, for example, from the document DE 20 2024 105 266 U1. In this case, a capacitive operating unit is proposed, in which a switching arrangement is arranged on the visual side of a carrier body and a capacitive sensor element is arranged on the rear side of the carrier body for detecting the switching states. Since only capacitive coupling and thus galvanic isolation exists through the carrier body, a high level of safety is provided, wherein a vehicle can be realized without the switching arrangement and thus in various variants while maintaining a plurality of identical parts.However, control units as are known from DE 20 2024 105 266 U1 have the disadvantage, on the one hand, that they are subject to restrictions with regard to the transparency or the translucence of the carrier body, and, on the other hand, that the sensor element must be arranged directly opposite the switching arrangement and in the immediate vicinity thereof in order to ensure a required capacitive coupling.The object of the invention is therefore to overcome the aforementioned disadvantages, to meet the given requirements and to provide an alternative for operator control units for motor vehicles.This object is achieved by the combination of features according to claim 1.According to the invention, an operating unit for a motor vehicle is therefore proposed. This has a translucent, at least translucent and preferably transparent carrier body, a switching arrangement and an optical transmitter and an optical sensor. The switching arrangement is arranged on a visible-side surface of the carrier body facing an operator, wherein said surface is preferably arranged directly or via an adhesive layer, which is also mentioned below, on the surface of the carrier body. The visible-side surface of the carrier body is thus facing an operator and visible for the latter. The optical transmitter and the optical receiver are arranged on a rear side of the carrier body facing away from the operator, wherein these can be provided with one another as an electronic module and, for example, on a common printed circuit board. Alternatively, however, the optical transmitter and the optical receiver can also be arranged separately from one another on the rear side of the carrier body facing away from the operator. The aforementioned switching arrangement has at least one switching element, which preferably has a refractive index that differs from a refractive index of the carrier body, is formed from an elastomer in particular at least in the region that bears against the contact surface or surface of the carrier body, and is movable by the operator between an actuated position, in which the switching element bears against a contact region of the vision-side surface assigned to the respective switching element, and an unactuated position, in which the respective switching element is spaced apart from the vision-side surface, such that optical reflection properties or else absorption properties at the respective contact region of the vision-side surface of the carrier body can be changed depending on the position of the respective switching element. Furthermore, the optical transmitter is configured to emit light through the carrier body to the contact region. In addition to this, the optical sensor is designed to detect a light decoupled from the carrier body, for example reflected at the contact region, and to determine the position of the at least one switching element from the decoupled or reflected light and to generate a switching signal corresponding to the position directly, for example by an integrated evaluation unit, or indirectly, for example by an external evaluation unit, which forms an electronics module with the optical sensor and / or the optical transmitter and can be provided with the latter on a common printed circuit board.In a clearly illustrated embodiment, the switching arrangement has at least two switching elements, each of which is movable by the operator between a respective actuated position, in which the respective switching element abuts a respective contact region of the vision-side surface, and a respective unactuated position, in which the respective switching element is spaced apart from the vision-side surface. Correspondingly, the optical transmitter is designed to emit light through the carrier body to the contact areas or to one of the contact areas, wherein in the latter variant an optical transmitter is provided for each switching element and is assigned to the respective contact area. For the optical sensor, it is preferably designed to detect the light decoupled from the carrier body, for example reflected at the contact regions, and to determine the positions of the at least two switching elements from the decoupled or reflected light and to generate a respective switching signal corresponding to the respective position. Alternatively, however, a plurality of optical sensors can also be provided, wherein in each case one optical sensor is assigned exactly to one switching element for determining its position.The optical sensor or optionally the optical sensors can also provide only sensor values which can be evaluated in the already mentioned separate evaluation unit, so that the respective switching signals can be generated therefrom by the evaluation unit. Accordingly, such an evaluation unit can be understood as being integrated into the at least one optical sensor or as being separated from the latter, but connected by signal technology.As already mentioned, the carrier body is preferably transparent. Additionally or alternatively, a likewise advantageous refinement provides that the carrier body is made of glass.The optical transmitter is in particular a lighting means, in particular an LED. Alternatively or additionally, the optical transmitter can be designed to emit light with a wavelength of preferably exclusively more than 780 nm or generally light in the infrared range or exclusively light in the infrared range. An IR LED is therefore particularly preferred as the optical transmitter. In principle, however, alternatively any desired light means can be used which is designed to emit any desired light in the range not visible to the human eye and preferably exclusively this light.For optimized coupling of the light into the carrier body and optionally also for decoupling the light from the carrier body, the latter preferably has a coupling surface on its rear side, on which the optical transmitter and optionally also the optical sensor are arranged.According to a first variant, a particularly advantageous development provides that the coupling surface is arranged tilted with respect to the surface or the coupling surface and the surface have a predetermined angle with respect to one another and the optical transmitter is arranged on the carrier body in such a way that the light coupled into the carrier body by the optical transmitter is reflected away from the optical sensor at the contact region of the switching element with the switching element in the unactuated position and is reflected away from the optical sensor at the contact region of the switching element with the switching element in the actuated position. If the light with the switching element in the unactuated position is reflected away from the optical sensor, the light is not detected by the latter, so that the optical sensor generates a switching signal according to which the respective switching element is in the unactuated position. If the light is reflected towards the optical sensor with the switching element in the actuated position, the light is detected by the latter, so that the optical sensor generates a switching signal according to which the respective switching element is in the actuated position.A likewise advantageous second variant provides, in a principle reversal, that the coupling surface is tilted with respect to the surface and the optical transmitter is arranged on the carrier body in such a way that the light coupled into the carrier body by the optical transmitter is reflected towards the optical sensor at the contact region of the switching element with the switching element in the unactuated position and is reflected away from the optical sensor at the contact region of the switching element with the switching element in the actuated position. If the light is reflected towards the optical sensor with the switching element in the unactuated position, the light is detected by the latter, so that the optical sensor generates a switching signal according to which the respective switching element is in the unactuated position. Analogously, the light with the switching element in the actuated position is reflected away from the optical sensor, so that the light is not detected by the latter, and the optical sensor generates a switching signal according to which the respective switching element is in the actuated position.For both variants, the optical sensor is designed to detect the light reflected at the contact region to the optical sensor and to determine the position of the at least one switching element from the reflected light.A third variant, but not based on direct reflection, additionally provides that the coupling-in surface is tilted with respect to the surface and the optical transmitter is arranged on the carrier body in such a way that the light coupled into the carrier body by the optical transmitter is reflected substantially or predominantly back into the carrier body at the contact region of the switching element with the switching element in the unactuated position and generates a predetermined first light intensity in the carrier body and is coupled substantially or predominantly out of the carrier body into the switching element at the contact region of the switching element with the switching element in the actuated position and generates a predetermined second light intensity in the carrier body. Proceeding from this, the optical sensor is designed to detect the light or its light intensity generated by the light coupled into the carrier body and to determine the position of the at least one switching element from the light intensity.If a plurality of switching elements are present, it is advantageous in the case of the third variant mentioned if each switching element is assigned an optical transmitter and preferably also in each case an optical receiver.Regardless of how the switching state or the position of the switching element is determined, it is advantageous if the coupling surface is tilted with respect to the surface of the carrier body and the optical transmitter is arranged on the coupling surface in such a way that the light coupled into the carrier body by the optical transmitter is reflected substantially completely back into the carrier body at the contact region of the switching element with the switching element in the unactuated position, so that the conditions for total internal reflection (TIR) are thus generated.In particular, a development is advantageous in which the switching arrangement has at least two switching elements with a respective contact region and the operating unit has exactly one optical sensor which is designed to detect a light decoupled from the carrier body in a manner specifically attributable to each contact region and to determine the position of the respective switching element from the decoupled light which can be specifically attributable to each contact region and to generate a switching signal corresponding to the position of the respective switching element.However, an operating unit can also have a plurality of switching arrangements which are arranged spaced apart from one another on the surface of the carrier body. In this case, each switching arrangement can be assigned at least one optical transmitter and at least one, but preferably exactly one, optical receiver. Alternatively, however, for example, each switching arrangement can be assigned at least one optical transmitter and a plurality of switching arrangements can be assigned one or exactly one optical receiver.Fundamentally, the optical sensor can be a simple brightness sensor, wherein one such optical sensor is then preferably assigned to each switching element. Preferably, however, optical sensors are used which allow matrix evaluation and thus both determine the light intensity and the distribution of the light intensity on their sensor surface, so that the position of a plurality of switching elements can be determined with such an optical sensor.Instead of an optical sensor which only determines the light intensity and measured values comparable to grey levels or a black-and-white evaluation, a simple camera could also be provided as the optical sensor.In order to minimize unwanted scattering of the light reflected at the switching arrangement or else at the contact surfaces, the carrier body can furthermore have at least one trapping surface which is designed to couple out and / or absorb a light coupled into the carrier body by the optical transmitter and reflected in the carrier body in order to reduce scattered light from the carrier body. For this purpose, the trapping surface can be arranged, for example, in the beam path of the light reflected by the switching arrangement or the contact surfaces and not reflected to the optical sensor, wherein the trapping surface can have, on the one hand, an angle optimized for decoupling as a function of the beam path and / or be configured in a matted manner.In addition or as an alternative to such a trap surface, an attachment part arranged directly on the carrier body can be provided, which is preferably designed to absorb light in general and IR light in particular.In order to enable the optical sensor to ascertain reference values or measurement values serving as a base value, it can additionally be provided that the optical transmitter is designed to emit the light in a predetermined pulsed manner, i.e. with predetermined pauses between two light pulses each, through the carrier body to the contact region, and the optical sensor is designed to ascertain a reference value by the pulsing.Furthermore, the switching arrangement can have at least one base body which is fixed on the surface, preferably fixed or bonded by adhesive bonding and is formed integrally as an operating element which acts on the at least one switching element or is connected to an operating element which acts on the at least one switching element. The control element can be, for example, a rocker button assigned to two switching elements in each case, which can actuate the switching elements individually by tilting them or jointly by pressing them, so that four positions of the control element are therefore made possible, which result in distinguishable combinations of the positions of the two switching elements. Alternatively, however, one button can also be provided for each switching element, which button is held on the base body.Based thereon, it can be provided that at least one contact layer of the base body abutting the surface and / or an adhesive layer arranged between the base body and the surface are differently colored with respect to the switching element, so that different optical reflection properties and / or different optical absorption properties result. For example, the base body and / or the adhesive layer can be colored black and the switching element or the switching elements can be colored white, which results in an advantageous contrast. Accordingly, the different reflection and absorption properties of the two colors or of the components lead to an increase in the sensor contrast, so that a better distinction of the two system components is made possible.In order to indicate to the operator an actuation, i.e. an attainment of the actuated position, it can additionally be provided that the operator control unit further comprises at least one haptic element for generating a haptic feedback, wherein at least one switching element is assigned a haptic element or is formed integrally therewith. The haptic element is designed to generate a haptic feedback for the operator when the switching element is moved from its unactuated position into its actuated position. A silicone dome, a switching mat or a snap-in disc can serve as the haptic element, for example.The features disclosed above can be combined as desired, provided that this is technically possible and they do not conflict with one another.Other advantageous developments of the invention are characterized in the dependent claims or are illustrated in more detail below together with the description of the preferred embodiment of the invention on the basis of the figures. The following are shown: FIG. 1 shows an operating unit in an unactuated position; FIG. 2 shows the operating unit in the unactuated position with the beam path; FIG. 3 shows the operating unit in a first actuated position; FIG. 4 shows the operating unit in a second actuated position; FIG. 5 shows the operating unit in a third actuated position; FIG. 6 shows a variant of the operating unit.The figures are schematic by way of example. Like reference numerals in the figures indicate like functional and / or structural features.FIGS. 1 to 5 show an identical operating unit 1 with different positions of the operating element 24 or of the switching elements 21, 22, on which the operating element 24 acts. FIG. 6 shows a variant of the operating unit 1 shown in FIGS. 1 to 5, wherein the details given in relation to FIGS. 1 to 5 also apply directly to the operating unit 1 according to FIG. 6.Basically, an operating unit 1 is to be provided which works with a completely closed surface on a body which is transparent for design reasons.FIG. 1 shows such an operating unit 1 according to one possible embodiment. This has a support body 10 that can be illuminated and in the present case is glass or is formed from glass, a switching arrangement 20 and an electronics module 30, wherein the support body 10 can also be formed from another transparent material.The operating unit 1 has a visible side S visible to the operator and facing it and a rear side R facing away from the operator. On the visible side S, the carrier body 10 is defined by a surface 13 on the corresponding visible side, on which the switching arrangement 20 is arranged.Regardless of a specific design of the switching arrangement 20, it is essential that it has at least one and in the present case exactly two switching elements 21, 22, which can be brought to rest on the surface 13 in a respective contact region 11, 12, which corresponds to their respective actuated position. A switching element 21, 22 spaced from the surface 13 is accordingly in its unactuated position.Provided on the rear side of the carrier body 10 is the electronic module 30, which has an optical transmitter 31 and an optical sensor 32, which are arranged on a common printed circuit board 33.Fundamentally, the optical transmitter 31 is intended to couple infrared light (IR light) into the carrier body 10 and in the direction of the switching arrangement 20, wherein the IR light is reflected at the switching arrangement 20 depending on the positions of the switching elements 21, 22. Depending on the reflection of the IR light, the optical sensor 32 acquires various measurement data from which it determines the position of the switching elements 21, 22 and generates a corresponding switching signal based thereon.For optimized coupling of the IR light from the optical transmitter 31 into the carrier body 10, but also for optimized coupling of the IR light from the carrier body 10 into the optical sensor 32, a coupling surface 14 designed for this purpose is provided. The coupling surface 14 and the surface 13 are tilted relative to one another in such a way that the conditions for total internal reflection are fulfilled for the IR light coupled in by the optical transmitter 31 with the switching elements 21, 22 in their unactuated position, so that the light is substantially completely reflected in the contact regions 11, 12 as long as the switching elements 21, 22 do not abut the contact regions 11, 12, i.e. are unactuated.The optical sensor 32 is not only a brightness sensor, but a sensor which can determine both the light intensity and its two-dimensional distribution on its sensor surface, so that the light reflected by each of the contact regions 11, 12 or by each of the switching elements 21, 22 can be detected by a single sensor 32 and the positions of the switching elements 21, 22 can be determined from this.According to the present embodiment, the switching arrangement 20 is realized as a rocker button. This has a base body 23 fixed to the surface 13 by an adhesive layer 25, on which the switching elements 21 formed by silicone domes and thus integrally providing haptic feedback are arranged. Furthermore, an operating element 24 is mounted on the base body 23 in a tiltable manner and movable in the direction of the surface 13, so that the operating element 24 can assume four different positions and four different positions of the switching elements 21 can be realized.FIG. 2 shows an unactuated position of the operating element 24, in which no external force acts on the operating element 24.FIG. 3 shows a first actuated position of the operating element 24, in which the operating element 24 is tilted in a first direction by an external force K 1 applied by the operator on the base body 23, and the second switching element 22 is displaced from its unactuated position into its actuated position by the base body 23, such that the second switching element 22 bears against the surface 13 in the associated contact region 12, but the first switching element 21 is spaced apart from the surface 13 and accordingly remains in its unactuated position.FIG. 4 shows a second actuated position of the operating element 24, in which the operating element 24 is tilted in a second direction opposite to the first direction by an external force K 2 applied by the operator on the base body 23, and the first switching element 21 is displaced from its unactuated position into its actuated position by the base body 23, such that the first switching element 21 bears against the surface 13 in the associated contact region 11, but the second switching element 22 is spaced apart from the surface 13 and accordingly remains in its unactuated position.FIG. 5 shows a third actuated position of the operating element 24, in which the operating element 24 is pressed against the base body 23 by an external force K 3 applied by the operator in the direction of the surface 13, and the base body 23 displaces both switching elements 21, 22 from their unactuated positions into their actuated positions, so that both switching elements 21, 22 bear against the surface 13 in the associated contact regions 11, 12.By way of example, a respective portion of a sensor image 34 captured by the optical sensor 31 is shown, in which the base body 23, more precisely its layer bearing against the surface 13 or the adhesive layer 24, and depending on the position no switching element 21, 22, one of the switching elements 21, 22 or both switching elements 21, 22 bearing against the respective associated contact region 11, 12 on the surface 13, are captured.To clarify the functional principle, FIGS. 2 to 5 also each show the relevant beam paths S 1, S 2 of the IR light coupled into the carrier body 10 by the optical transmitter 31 and incident on the contact regions 11, 12.According to FIG. 2, none of the switching elements 21, 22 is actuated, so that the light is reflected along the beam paths S 1, S 2 at the contact regions 11, 12 back into the carrier body 10 and away from the optical sensor 32. This evaluation electronics or an evaluation electronics possibly connected to the optical sensor 32 thus do not generate a switching signal.According to FIG. 3, only the second switching element 22 is actuated, so that the light is reflected along the associated beam path S 2 at the contact region 12 back into the carrier body 10 and to the optical sensor 32. This evaluation electronics or the evaluation electronics possibly connected to the optical sensor 32 thus generate a switching signal which indicates that the second switching element 22 is actuated. The details given for FIG. 2 apply to the beam path S 1 or the first switching element 21.According to FIG. 4, only the first switching element 21 is actuated, so that the light is reflected along the associated beam path S 1 at the contact region 11 back into the carrier body 10 and to the optical sensor 32. This evaluation electronics or the evaluation electronics possibly connected to the optical sensor 32 thus generate a switching signal which indicates that the first switching element 21 is actuated. The details given for FIG. 2 apply to the beam path S 2 or the second switching element 22.According to FIG. 5, both switching elements 21, 22 are actuated, so that the light is reflected along the associated beam paths S 1, S 2 at the contact region 12 back into the carrier body 10 and to the optical sensor 32. This evaluation electronics or the evaluation electronics possibly connected to the optical sensor 32 thus generate a switching signal which indicates that both switching elements 21, 22 are actuated.FIG. 6 additionally shows that the operating unit 1 can comprise a decorative panel 41 or be combined with such a panel. Such a decorative screen 41 covers edge sections of the carrier body 10, so that on the one hand the edge sections and on the other hand an electronic system arranged in this region are not visible to the operator.Furthermore, the carrier body 10 can have a trapping surface 15 which can be combined with an attachment part 42 for absorbing light. By means of a, for example, matt-finished trapping surface 15 and the attachment part 42 configured to absorb light, the scattered light component can be greatly reduced by the light coupled into the carrier body 10 by the optical transmitter 31 and the sensor accuracy of the optical sensor 32 can be improved.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 20 2024 105 266 U1 [0007, 0008]

Claims

Operator control unit (1) for a motor vehicle, having a fluoroscopic carrier body (10), a switching arrangement (20) which is arranged on a vision-side surface (13) of the carrier body (10) facing an operator, and an optical transmitter (31) and an optical sensor (32) which are arranged on a rear side (R) of the carrier body (10) facing away from the operator, wherein the switching arrangement (20) has at least one switching element (21, 22) which is movable between an actuated position in which the switching element (21, 22) bears against a contact region (11, 12) of the vision-side surface (13) associated with the respective switching element (21, 22), and an unactuated position in which the respective switching element (21, 22) is spaced apart from the vision-side surface (13), such that optical reflection properties at the respective contact region (11, The method according to the invention can be used to modify the surface (13) of the carrier body (10) on the viewing side as a function of the position of the respective switching element (21, 22), wherein the optical transmitter (31) is designed to emit light through the carrier body (10) to the contact region (11, 12), and the optical sensor (32) is designed to detect a light coupled out of the carrier body (10) and to determine from this the position of the at least one switching element (21, 22) and to generate a switching signal corresponding to the position.Operating unit according to Claim 1, wherein the carrier body (10) is transparent and / or made of glass.Operating unit according to Claim 1 or 2, wherein the optical transmitter (31) is a lighting means and / or is designed to emit light having a wavelength of more than 780 nm.Operating unit according to one of the preceding claims, wherein the carrier body (10) has, on the rear side (R), a coupling surface (14), on which the optical transmitter (31) is arranged.Operating unit according to the preceding claim, wherein the coupling surface (14) is tilted with respect to the surface (13) and the optical transmitter (31) is arranged on the carrier body (10) in such a way that the light coupled into the carrier body (10) by the optical transmitter (31) is reflected away from the optical sensor (32) at the contact region (11, 12) of the switching element (21, 22) with the switching element (21, 22) in its unactuated position and is reflected towards the optical sensor (32) at the contact region (11, 12) of the switching element (21, 22) with the switching element (21, 22) in its actuated position, or that the light coupled into the carrier body (10) by the optical transmitter (31) is reflected towards the optical sensor (32) at the contact region (11, 12) of the switching element (21, 22) with the switching element (21, 22) in its unactuated position and is reflected towards the optical sensor (32) at the contact region (11, 12) of the switching element (21, 12), The optical sensor (32) is configured to detect the light reflected at the contact region (11, 12) to the optical sensor (32) and to determine the position of the at least one switching element (21, 22) from the reflected light with the switching element (21, 22) in its actuated position being reflected away from the optical sensor (32).Operating unit according to Claim 4, wherein the coupling-in surface (14) is tilted with respect to the surface (14) and the optical transmitter (31) is arranged on the carrier body (10) in such a way that the light coupled into the carrier body (10) by the optical transmitter (31) is reflected back into the carrier body (10) at the contact region (11, 12) of the switching element (21, 22) with the switching element (21, 22) in its unactuated position and generates a predetermined first light intensity in the carrier body (10) and is coupled out from the carrier body (10) into the switching element (21, 22) at the contact region (11, 12) of the switching element (21, 22) with the switching element (21, 22) in its actuated position and generates a predetermined second light intensity in the carrier body (10), wherein the optical sensor (32) is configured, detecting the light intensity generated by the light coupled into the carrier body (10) and determining the position of the at least one switching element (21, 22) from the light intensity.Operating unit according to one of Claims 4 to 6, wherein the coupling-in surface (14) is tilted with respect to the surface (13) and the optical transmitter (31) is arranged on the coupling-in surface (14) in such a way that the light coupled into the carrier body (10) by the optical transmitter (31) is reflected substantially completely back into the carrier body (10) at the contact region (11, 12) of the switching element (21, 22) with the switching element (21, 22) in its unactuated position.Operating unit according to one of the preceding claims, wherein the switching arrangement (20) has at least two switching elements (21, 22) with a respectively assigned contact region (11, 12) and the operating unit (1) has exactly one optical sensor (32) which is designed to detect a light coupled out of the carrier body (10) in a manner specifically attributable to each contact region (11, 12) and to determine the position of the respective switching element (21, 22) from the decoupled light specifically attributable to each contact region (11, 12) and to generate a switching signal corresponding to the position of the respective switching element (21, 22).Operating unit according to one of the preceding claims, wherein the carrier body (10) has at least one trapping surface (15) which is designed to couple out and / or absorb a light which is coupled into the carrier body (10) by the optical transmitter (31) and reflected in the carrier body (10), in order to reduce scattered light from the carrier body (10).Operating unit according to one of the preceding claims, wherein the optical transmitter (31) is designed to emit the light in a predetermined pulsed manner through the carrier body (10) to the contact region (11, 12), and the optical sensor (32) is designed to determine a reference value for the unactuated position of the at least one switching element (21, 22) by means of the pulsing.Operating unit according to one of the preceding claims, wherein the switching arrangement (20) has at least one base body (23) fixed on the surface, which is formed integrally as an operating element (24) acting on the at least one switching element (21, 22) or is connected to an operating element (24) acting on the at least one switching element (21, 22), wherein at least one contact layer of the base body (23) lying against the surface (13) and / or an adhesive layer (25) arranged between the base body (23) and the surface (13) are differently coloured with respect to the switching element (21, 22), so that different optical reflection properties and / or different optical absorption properties result.Operating unit according to one of the preceding claims, further comprising at least one haptic element, wherein at least one switching element (21, 22) is assigned to a haptic element or is formed integrally therewith, wherein the haptic element is formed to generate a haptic feedback for the operator when the switching element (21, 22) is moved from its unactuated position into its actuated position.

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