Heating a lens module of a camera for a motor vehicle

Abstract

A camera (2) for a motor vehicle (1) comprises a lens housing (4), a lens holder body (5), which is mechanically connected to the lens housing (4), and an electrical heater element (8) for heating the lens module. The heater element (8) is arranged at the top of the lens module and the heater element (8) is electrically connected to the circuit board (17) via the lens holder body (5) and lens housing (4).

Description

[0001] 2023PF03217

[0002] Description

[0003] Heating a lens module of a camera for a motor vehicle

[0004] The present invention is directed to a camera for a motor vehicle, the camera comprising a lens module, a lens holder body, which is mechanically connected to the lens module, and an electrical heater element for heating the lens module. The invention is further directed to an electronic vehicle guidance system or advanced driver assistance system comprising such a camera and to a method for heating a lens module of a camera for a motor vehicle.

[0005] Cameras arranged on motor vehicles are known in various configurations. In this context, it is known that cameras are formed and arranged for capturing the environment of the motor vehicle. However, cameras may also be employed for the capturing an interior of the vehicle and may be arranged correspondingly. Thus, the cameras may be exposed to significant temperature fluctuations and / or other environmental conditions. Moreover, the cameras are also exposed to mechanical stress due to the vibrations while the vehicle is moving. Cameras for motor vehicles should therefore be designed to still operate as desired under said conditions and to achieve sufficiently good image quality. The images may then be provided to driver assistance systems or other electronic vehicle guidance system, which may use them as an input for driver assistance or at least partly automatically guiding the vehicle.

[0006] One circumstance that may lead to degraded image quality, especially with cameras mounted externally on the vehicle, is when ice or fogging builds up on the lens of the camera due to low environmental temperatures.

[0007] Document KR20240037127A describes a vehicle camera module with a heater element. It consists of a barrel containing multiple lenses, a space for lens insertion, and a lens assembly with a heater element to generate heat for the lens surface. Additionally, it includes a sensor circuit board, a power circuit board for supplying power, and a rear body. This design allows for rapid removal of frost, condensation, and freezing on the lens surface caused by external temperature variations, ensuring clear visibility and image quality for the camera. 2023PF03217

[0008] Document DE 102015 116 962 Al describes a camera for a vehicle with a heating unit for heating a lens of the camera. The heating unit is designed as an elongated wire element, which is guided through an axial channel from the lens to a circuit board, which is arranged axially distant from the lens.

[0009] In such known cameras, heater elements require wirings to connect the heater elements to an energy source. The wiring is a potential weak spot where the camera can be damaged by external influences or during installation. Therefore, an efficient way to connect the heater element to an energy source is needed.

[0010] It is an objective of the present invention to provide a more reliable electrical contacting of the heater element for heating a lens module of a camera for a vehicle.

[0011] This objective is achieved by the respective subject matter of the independent claims. Further implementations and preferred embodiments are the subject matter of the dependent claims.

[0012] The invention is based on the idea to place the heater close to the lens glass which serves as a protective cover in a parallel way to the lens module and provide the electrical connection to the heater through an extension from the heater. Since the heater element will be close to the protective cover and needs to be powered from the circuit board (printed circuit board) of the camera, an electrical connection is needed between the circuit board and the lens heater. Electrical power to the heater is supplied from the circuit board through lens holder body, which has at least one electrical contacting element on it. Lens holder body is mechanically connected to the lens housing which has an at least one spring on it. The lens holder body also maintains an electrical connection with the lens housing. The heater is powered from the circuit board through the lens holder body, lens housing and spring with the extension of the heater.

[0013] The objective is achieved by a camera for a motor vehicle and the camera comprises at least one circuit board, a lens housing, a lens holder body which is mechanically connected 2023PF03217 to the lens housing, a heater element for heating a lens module inside the lens housing. The camera further comprises at least one electrical contacting element, which is arranged at a surface of the lens holder body and electrically connected to the circuit board. The at least one electrical contacting element is fitted at an inner surface of the lens holder body and the at least one spring is fitted around the lens housing such that the electrical contacting element is electrically connected to the spring when the lens holder body is mechanically connected to the lens housing.

[0014] According to an aspect of the invention, a camera for a motor vehicle is provided. The camera comprises a lens housing, a lens holder body, which is mechanically connected to the lens housing, and a heater element for heating the lens module. The heater element is placed parallel to the lens module on the upper surface of the internal barrel just under the protective cover. Once the heater element is powered it heats the lens module particularly the protective cover and easily removes the fog or ice on the protective cover or lens module.

[0015] In an alternative embodiment the heater element is placed parallel to the lens module on the upper surface of the internal barrel without a protective cover.

[0016] The lens housing may be understood to comprise a lens module and at least one lens arranged within the lens module. Therein, the lens housing may, for example, enclose the at least one lens circumferentially. The lens housing has a front opening and a rear opening, wherein front and rear may be understood with respect to an axial direction of the lens housing, the lens module and the camera, respectively. In particular, a longitudinal axis of the camera, which is identical to a longitudinal axis of the lens housing and the lens module, is identical or parallel to an optical axis of the at least one lens. The front opening of the lens housing is located at an axial end of the lens housing, which faces away from an imager chip of the camera and the rear opening of the lens housing is located at an opposite axial end of the lens housing, which faces the imager chip.

[0017] The lens module and particularly the protective cover on the top of the lens module is heated via the heater element. The heater element is close to the protective cover and 2023PF03217 placed in between the lens module and the protective cover so thermal loss is prevented and maximum heat is supplied to the lens module and the protective cover. Therefore, built up ice or fog on the lens module and / or the lens housing and / or the protective cover may be removed by the heating.

[0018] The lens holder body is located at the rear end and at the rear opening of the lens housing. The lens holder body may, in particular, be used for connecting the lens housing to the vehicle. Apart from the lens housing and the lens holder body, the camera may comprise one or more further components, in particular mounting components or housing components, for mounting the camera and the lens module to the vehicle. For example, the camera may comprise a rear housing body, which is connectable to the vehicle and connected to the lens holder body such that the lens holder body is arranged between the rear housing body and the lens housing respectively. The lens holder body being mechanically connected to the lens housing may be understood such that the lens holder body is mechanically connected, for example screwed or clamped, to the lens housing.

[0019] The heater element being arranged at the surface facing away parallel to the lens module and protective cover may be understood such that the heater element is attached to or fixed to or fastened to the lens module surface. For example, the heater element may be glued by an adhesive material, for example a pressure sensitive adhesive, to the surface. However, also other types of adhesives may be used. Alternatively, the heater element may be pressed onto the surface by means of a further component or housing component of the camera. In other words, it is possible that the heater element is fastened to the surface by a material bond, but this is not necessarily the case in every embodiment.

[0020] The heater element is designed as an electrical heater element and may produce the heat itself when electric current is supplied to the heater element. For example, the heater element may be implemented as a flexible / flex heater element. A flexible heater is a chemically etched, screen printed, or wire wound heater which can be flexed or bent to conform to the contours of the surface which requires heating. 2023PF03217

[0021] The heat, which is originally generated in or at the heater element, is directly heating the lens module and the protective cover without interfering with any intermediate components.

[0022] When designing an actual implementation of the camera, the thermal connection may be tuned by choosing the respective materials of the lens holder body and the lens housing as well as the connection technology to connect the lens housing to the lens holder body. According to the concrete requirements, different choices may be possible. Preferably, the lens holder body and / or the lens housing may contain a metal material, such as aluminum, or consist or predominantly consist of the metal material. Furthermore, for a given thermal conductivity, the size and heating power of the heater element may be further tuned in order to achieve the requirements. In some other embodiments camera, lens housing and lens holder body can also predominantly consist of plastic or plastic like materials.

[0023] According to the invention, the effort for electrically connecting the heater element is optimized since the heater element is placed close to the lens module and a protective cover on the upper surface of the internal barrel.

[0024] Further electronic components, such as the imager chip or driving components or evaluation components, may be placed on a circuit board of the camera, which is located on a side of the lens holder body opposite to the lens housing. Thus, the distance between these further electronic components and the heater element may be particularly long in a camera according to the invention. Therefore, by providing extension from the heater element and connecting pads, electrical connection is established for the heater.

[0025] The power supply for the heater element may be located on the circuit board as well or may be located externally to the camera and connected to the heater element via the circuit board. Thus, an electrical connection is necessary between the circuit board and the heater element and can therefore needs to be particularly short and simple. In particular, the heater element may be located close to the lens module and the protective cover on the upper surface of the internal barrel. Furthermore, while the lens module may be in principle movable with respect to the circuit board or other housing components of the camera, the 2023PF03217 heater element and the lens holder body needs a connection to the circuit board. Therefore, the electrical connection between the heater element and the circuit board may require additional connection and contacting points.

[0026] According to several implementations of the camera according to the invention, the camera comprises the circuit board and the circuit board is arranged at a side of the lens holder body facing away from the lens module. The circuit board comprises supply circuitry for supplying electrical current to the heater element to heat the heater element. The heater element is electrically connected to the supply circuitry.

[0027] The supply circuitry may comprise a power source, in particular a current source or a voltage source, to supply the electrical current to the heater element. However, in other implementations, the supply circuitry may be connected to an external power source, which is arranged external to the circuit board and / or external to the camera. The power source may then supply the electrical current indirectly to the heater element via the supply circuitry. In the simplest case, the supply circuitry consists of electrical connections to connect the heater element and the external power supply to each other.

[0028] According to several implementations, the heater element is arranged on the lens housing on the top surface of the internal barrel facing to a protective cover.

[0029] In particular, lens housing comprises internal and external barrels. Lens internal elements are to be assembled inside the internal barrel component. The heater element has an extension to supply the power from the circuit board and the extension is placed on a slot formed on the outer surface of the internal barrel. Therefore, the extension of the heater element is placed and secured between the internal barrel and the external barrel.

[0030] The internal barrel and the external barrel are to be assembled by threading both components together. To ensure a secure and permanent connection, thread lock is applied during the assembly process. Assembly proceeds until both components reach designated stopper features, halting the threading process. Furthermore, thread lock must be consistently applied to the barrel thread to maintain the integrity of the assembly. Additionally, to fully 2023PF03217 seal the assembly and fill any gaps between the heater and the external barrel, the use of epoxy glue (potting) may be necessary. This method offers a comprehensive approach to securely joining the internal and the external barrels while also ensuring proper sealing for optimal device functionality.

[0031] According to several implementations, the lens holder body comprises at least one preferably two springs surrounding the lens holder body in an annular way. The at least one connecting pad of the heater extension is in direct contact with the springs. On the other side of the spring, there is at least one protrusion to serve as electrical connecting elements. When the lens holder body and the lens housing are mechanically connected, those protrusions are mechanically and electrically connects the electrical contacting elements which are placed on the contacting surface of the lens holder body. Then lens holder body comprises at least one busbar, which is electrically connected to the circuit board. The busbar mentioned here can be a circuitry printed on plastic or a conductive metal

[0032] In the assembly process, an O-Ring is positioned on the flange of the external barrel, serving as a seal. A protective cover (glass) component is then placed on top of an o-ring, with the seal in a compressed position ensuring the protective cover rests atop the heater element which faces towards the protective cover. Subsequently, a cap is threaded onto the external barrel, with thread lock applied during assembly. The threading process halts until the protective cover reaches the hard stop flange of the internal barrel, where the heater element is adhesively assembled. At this point, the o-ring seal is compressed to the desired height, completing the assembly of the components.

[0033] The heater element has an extension, which ensures a connection between the heater element and the springs. The extension of the heater element has at least one connecting pads to be contacted with the springs. Those connecting pads serve as positive (+) and negative (-) terminals. The positive terminal is where the positive voltage from the power source is connected. It is the entry point for the electrical current. The negative terminal is where the electrical current exits the heater and returns to the power source, completing the circuit. 2023PF03217

[0034] The positive and negative terminals can be formed as a separated connecting pads as well as a single connecting pad. A single connecting pad on the heater surface is divided into two electrically isolated sections: one for the positive terminal and one for the negative terminal.

[0035] In the assembly process, at least one preferably two springs are affixed to the internal barrel. This overmold assembly is secured to the internal barrel either through latches / clips or by using epoxy glue. Once the springs are firmly fixed to the internal barrel, particular attention is paid to ensuring that the two springs facing the connecting pads are always mated or in contact position. This arrangement is crucial for powering the heater element. Additionally, on the opposite external side of the springs are formed as a protrusion to serve as provision electrical connecting element for the connection to the lens holder body. A plastic insulator and the springs are sub-assembly by overmolding.

[0036] On the lens holder body, there is at least one electrical contacting element, which provide direct connections with the lens housing to supply electric energy. On the lens holder body, there are also at least one busbar, which is in contact with circuit board that supplies electric to the heater element. The electrical contacting elements and busbar are to be overmolded with a plastic insulator. This plastic insulator prevents short circuits when the busbar connections are assembled to the aluminum or any metal lens holder body. The lens holder body is impact extruded and includes a slot for the overmolded busbar and plastic insulator assembly. Once inserted into the lens holder body slot, the overmolded busbar and plastic insulator will be secured with latches, clips, press fit, or epoxy glue / potting assembly.

[0037] In one embodiment the external barrel is threaded to the internal barrel with applied thread lock on the thread profile to secure the both barrels in the lens housing assembly.

[0038] The spring comprise an electrical connecting element forming as a protrusion and they are the main connection points to the electrical contacting elements which are placed on the lens holder body. 2023PF03217

[0039] The protective cover is securely fastened by threading the lens cap onto the external barrel. Applying thread lock to the thread ensures that the cap remains tightly secured, preventing any loosening or disassembly from the external barrel over the vehicle's lifetime.

[0040] O-ring is applied in between the protective cover and the external barrel to ensure the assembly is watertight and well sealed.

[0041] In one embodiment the heater element is always in direct contact with the surface of the protective cover, located against the internal barrel flange. In this way, the heating system of the heater element is sufficiently applied directly to the protective cover. This will reduce the time to clear off the ice or frost from the surface of the protective cover.

[0042] According to several implementations, the circuit board comprises a supply contact and lens holder body is connected to the circuit board through the busbar. The electrical current supplied by the circuit board may then flow from the supply contact via the busbar to the lens holder body and from lens holder body to the lens housing through at least one electrical contacting element on the lens holder body and the protrusion on the spring. The heater element is in direct contact with the at least one spring through the extension of the heater element and connecting pads on the extension. Therefore, the electrical current flows from circuit board to the lens holder body via the busbar and then from the electrical contacting elements to the protrusion on the spring, from spring to the connecting pads and from connecting pads to the heater through the extension.

[0043] According to several implementations, the heater element is designed as a flexible heater element. For example, the heater element may comprise a flexible sheet heater. For example, the heater element may comprise a heating wire or another conductive structure, for example an etched foil or an etched conducting path on a lens, et cetera. The heating wire or other conductive structure may be embedded in an electrically nonconductive material forming a sheet, for example a flexible sheet, such as a silicone rubber material, a polyimide, et cetera. The heater element may also comprise a flexible circuit board covered with an electrically insulating material. 2023PF03217

[0044] Flexible heaters are commonly found in the form of single-layer flexible circuits, employing materials like copper or resistive alloys such as Inconel and Cupro-nickel to create conductive paths. When an electrical current passes through these materials with higher resistance, it produces heat. The dimensions of the conductor, including width and thickness, are chosen to achieve the desired resistance level corresponding to the supplied voltage. Dielectric materials are chosen according to the operational temperature range and power density required for the heater.

[0045] Such heater elements have the advantage that they require particularly little space between the lens module and the protective cover. They also may be attached to the lens module in a particularly simply way, for example by pressing it against the surface or by gluing it on the surface with an adhesive. On the other hand, such heater elements are available in various geometrical shapes and with sufficient heating power to fulfill said requirements in the camera.

[0046] According to several implementations, the camera comprises a rear housing body, which is connected to the lens holder body. The rear housing body and the lens holder body together define an assembly space and the circuit board is arranged completely inside the assembly space.

[0047] In particular, the rear housing body is arranged on the side of the lens holder body facing away from the lens module. The assembly space is separated from the environment of the camera by the rear housing body and / or the lens holder body. The circuit board may also be arranged inside of the assembly space, in particular completely inside the assembly space. The rear housing body may comprise an opening for a connector cable to connect the circuit board to the motor vehicle, in particular to an electronic control unit, ECU, of the motor vehicle.

[0048] In such implementations, the circuit board may be protected effectively from external or environmental influences such as pollution, soiling, humidity, et cetera. 2023PF03217

[0049] According to several implementations, the lens holder body comprises a metal material or consists of the metal material, wherein the metal material comprises or forms the surface at which the electrical contacting elements are arranged. The lens holder body may also comprise a plastic or non-conductive material.

[0050] According to several implementations, the lens housing comprises an external thread and the lens holder body comprises an internal thread. The lens holder body is fastened to the lens housing via the internal thread and the external thread.

[0051] In alternative implementations, the lens housing comprises the internal thread and the lens holder body comprises the external thread.

[0052] By fastening the lens holder body to the lens housing via the internal and the external thread, a direct contact between the electrical contacting elements and the protrusions is achieved.

[0053] According to several implementations, the lens housing comprises the rear opening, which faces the lens holder body, wherein the optical axis of the at least one lens passes through the rear opening. The lens holder body comprises a through hole, which is aligned with the rear opening.

[0054] The through hole being aligned with the rear opening means, in particular, that the optical axis passes through the rear opening and through the through hole. In particular, a center of the through hole may match a center of the rear opening and the optical axis may pass through the centers of the rear opening and the through hole.

[0055] In particular, an imager chip, which is for example arranged on a surface of the circuit board facing the lens holder body and the lens module, may also be aligned with the optical axis of the at least one lens. 2023PF03217

[0056] The camera may also comprise processing or pre-processing circuitry for processing or pre-processing imager signals generated by the imager chip upon the light hitting the active surface of the imager chip.

[0057] According to a further aspect of the invention, an electronic vehicle guidance system or advanced driver assisting system comprising a camera according to the invention is provided.

[0058] An electronic vehicle guidance system may be understood as an electronic system, configured to guide a vehicle in a fully automated or a fully autonomous manner and, in particular, without a manual intervention or control by a driver or user of the vehicle being necessary. The vehicle carries out all required functions, such as steering maneuvers, deceleration maneuvers and / or acceleration maneuvers as well as monitoring and recording the road traffic and corresponding reactions automatically. In particular, the electronic vehicle guidance system may implement a fully automatic or fully autonomous driving mode according to level 5 of the SAE J3016 classification. An electronic vehicle guidance system may also be implemented as an advanced driver assistance system, ADAS, assisting a driver for partially automatic or partially autonomous driving. In particular, the electronic vehicle guidance system may implement a partly automatic or partly autonomous driving mode according to levels 1 to 4 of the SAE J3016 classification. Here and in the following, SAE J3016 refers to the respective standard dated June 2018.

[0059] Guiding the vehicle at least in part automatically may therefore comprise guiding the vehicle according to a fully automatic or fully autonomous driving mode according to level 5 of the SAE J3016 classification. Guiding the vehicle at least in part automatically may also comprise guiding the vehicle according to a partly automatic or partly autonomous driving mode according to levels 1 to 4 of the SAE J3016 classification.

[0060] The electronic vehicle guidance system may, for example, comprise a control unit, which is configured to generate one or more control signals depending on image data generated by the camera, in particular by the imager chip and / or the processing or pre-processing circuitry. The control signals may be supplied by the control unit to one or more actuators of the motor vehicle to guide the motor vehicle at least in part automatically. 2023PF03217

[0061] Alternatively or in addition, the electronic vehicle guidance system may comprise a display device, which is configured to display an image depending on the image data generated by the camera to a user of the motor vehicle.

[0062] According to a further aspect of the invention, also a motor vehicle comprising an electronic vehicle guidance system according to the invention and / or a camera according to the invention is provided.

[0063] According to a further aspect of the invention, also a method for heating a lens module of a camera for a motor vehicle is provided. According to the method, a heater element is arranged at the surface of a lens module in direct contact with the protective cover on the upper surface of the internal barrel.

[0064] Further implementations of the method according to the invention follow directly from the various implementations of the camera according to the invention, the electronic vehicle guidance system and the motor vehicle according to the invention, and vice-versa. In particular, a camera according to the invention may carry out or may be used to carry out a method according to the invention or carries out such a method.

[0065] Further features of the invention are apparent from the claims, the figures and the figure description. The features and combinations of features mentioned above in the description as well as the features and combinations of features mentioned below in the description of figures and / or shown in the figures may be comprised by the invention not only in the respective combination stated, but also in other combinations. In particular, embodiments and combinations of features, which do not have all the features of an originally formulated claim, are also comprised by the invention. Moreover, embodiments and combinations of features which go beyond or deviate from the combinations of features set forth in the recitations of the claims are comprised by the invention.

[0066] Fig. 1 shows schematically a motor vehicle with an exemplary implementation of a camera according to the invention; 2023PF03217

[0067] Fig. 2 shows schematically exploded perspective view of a further exemplary implementation of a camera according to the invention;

[0068] Fig. 3 shows schematically an exploded perspective view of a part of a further exemplary implementation of a camera according to the invention;

[0069] Fig. 4 shows schematically an exploded perspective view of a part of a further exemplary implementation of a camera according to the invention;

[0070] Fig. 5 shows schematically a perspective view of a part of a further exemplary implementation of a camera according to the invention: and

[0071] In the figures, identical or functionally identical elements are provided with the same reference signs.

[0072] In Fig. 1, a motor vehicle 1 comprising at least one camera 2, for example a front camera, side cameras and / or a rear camera, which is implemented according to an exemplary embodiment of the present invention is shown in a top view. Here, the motor vehicle 1 is formed as a passenger car. The motor vehicle 1 comprises an electronic vehicle guidance system according to the invention, wherein the camera 2 may be considered as a part of the electronic vehicle guidance system. The electronic vehicle guidance system comprises a control unit 3, which may for example be formed by an electronic control unit, ECU, of the motor vehicle 1.

[0073] In the shown example, the motor vehicle 1 comprises four cameras 2, which are arranged distributed at the motor vehicle 1. One of the cameras 2 is arranged in a rear area, one of the cameras 2 is arranged in a front area of the motor vehicle 1 and the remaining two cameras 2 are arranged in respective lateral areas, in particular in vicinities of the wing mirrors. 2023PF03217

[0074] The number and arrangement of the cameras 2 may, however, be different in other examples. Alternatively, in addition one or more cameras according to the invention may be arranged for capturing an interior space or a passenger compartment of the motor vehicle 1.

[0075] The camera 2 is, in particular, installed such that it is assembled to a respective individual motor vehicle component. A motor vehicle component may for example be a bumper or an exterior mirror or a side trim. The motor vehicle component may also be a headliner or an interior trim or a cover of a steering wheel center or an interior mirror. The mentioned motor vehicle components are to be considered only as non-limiting examples.

[0076] In an embodiment, an environmental region of the motor vehicle 1 may be captured by the camera 2. In case of four cameras 2, the four cameras 2 may preferably be formed identical in construction. In particular, an image sequence or video data can be provided by the camera 2, which describes the environmental region. The video data may be transmitted from the camera 2 to the control unit 3. By means of the control unit 3, a display device (not shown) of the motor vehicle 1 may be controlled such that the video data of the camera 2 can be displayed to a user of the motor vehicle 1. Thus, the electronic vehicle guidance system may operate as a driver assistance system for assisting a driver of the motor vehicle 1 in driving the motor vehicle 1. Alternatively or in addition, the control unit 3 may process the video data and generate at least one control signal for one or more respective actuators (not shown) of the motor vehicle 1, which may control the motor vehicle 1 automatically or in part automatically based on the control signals.

[0077] Fig. 2 shows a perspective view of an exemplary implementation of a camera 2 according to the invention, as it may be used in a motor vehicle 1 or the corresponding electronic vehicle guidance system described with respect to Fig. 1, for example.

[0078] The camera 2 comprises a housing, which includes a rear housing body 16 connected to a lens holder body 5 such that an assembly space is formed within a region enclosed by the rear housing body 16 in combination with the lens holder body 5. 2023PF03217

[0079] The camera 2 further comprises a lens module with a lens housing 4, which is attached to the lens holder body 5 on a side opposite to the rear housing body 16 and the assembly space. In particular, the lens housing 4 may comprise an external thread (not shown) and the lens holder body 5 may comprise an internal thread (not shown) and the lens holder body 5 may be fastened to the lens housing 4 by means of the internal thread and the external thread. In alternative implementations, the lens holder body 5 may comprise an external thread and the lens housing 4 may comprise an internal thread to connect the external thread of the lens holder body 5.

[0080] For example, the lens housing 4 may comprise a hollow shaft, which has, for example, an approximately cylindrical inner shape and encloses one or more optical lenses of the lens module and the camera 2, respectively. The optical axis of the lenses is, in particular, parallel or identical to a longitudinal axis of the hollow shaft. The longitudinal axis of the hollow shaft may therefore be considered as the longitudinal axis of the lens module and the longitudinal axis of the camera 2, respectively. It will be denoted as longitudinal axis in the following, if not denoted otherwise. For example, the external thread may be arranged on an outer side of the hollow shaft.

[0081] The lens holder body 5 may comprise a through hole aligned with the hollow shaft of the lens housing 4 to allow for light entering the camera 2 via the lenses and the lens housing 4 through the hollow shaft and the through hole into the assembly space. Within the assembly space, a circuit board 17 of the camera 2 may be arranged, which carries an imager chip (not shown) of the camera 2, which is also aligned with the hollow shaft, the through hole and the optical axis as well as the longitudinal axis, respectively. Therefore, light entering the camera and entering, through the hollow shaft and the trough hole, the assembly space may hit an active optical surface of the imager chip. The imager chip generates respective imager signals, which may be transmitted to the control unit 3 via an opening in the rear housing body 16 and the corresponding cable connection (not shown). Alternatively, the circuit board 17 may comprise pre-processing circuitry, such as a digital signal processor (DSP), a microcontroller, a graphics processing unit (GPU), et cetera, to pre-process the imager signals and to provide the pre-processed imager signals to the control unit 2023PF03217

[0082] 3. The control unit 3 may then generate the video data depending on the imager signals or the pre-processed imager signals, respectively.

[0083] The lens holder body 5 has a surface, which faces away from the lens housing 4 and faces the rear housing body 16, the circuit board 17 and the assembly space, respectively. According to the through hole of the lens holder body 5, the surface has an opening, for example a circular opening. The camera 2 comprises an electric heater element 8, in particular a flexible heater element 8.

[0084] The heater element 8 may for example be implemented as a flexible heater foil, which is arranged on the surface of the lens module close to the protective cover 15. The heater element 8 may for example be attached to the surface by mechanical pressure or by means of an adhesive. For example, a pres sure- sensitive adhesive may be used, which allows for a simple assembly of the camera during production since no specific hardening steps, such as UV-hardening or thermal hardening, must be carried out. However, also other types of adhesives may be used.

[0085] Lens housing 4 comprises an internal barrel 10 and an external barrel 11 and within the internal barrel 10 a lens module is placed containing lenses. The heater element 8 is placed on the surface of the lens module close to the protective cover 15 on the upper surface of the internal barrel 10 and the extension 12 of the heater element 8 is placed on the slot (not shown) of the internal barrel 10. At the edge of the extension 12, there are at least one connecting pad 13. Those connecting pads 13 serve to electrically supply the heater element 8.

[0086] The lens holder body 5 features a nearly cylindrical hollow cavity in its center, designed to accommodate the lens housing 4. The lens housing 4 is mechanically connected to the inner surface of the lens holder body 5. This inner surface corresponds to the cavity within the lens holder body 5, ensuring secure placement and functionality of the lens housing 4. 2023PF03217

[0087] The inner surface of the lens holder body 5 also accommodates the at least one preferably two electrical contacting elements 7. Contacting surfaces of the electrical contacting elements 7 to the lens holder body 5 are insulated with an insulation material and the electrical contacting elements 7 are conductive to supply electric energy to the heater 8.

[0088] At least one spring 18 is overmolded to the internal barrel 10. The spring 18 provide a contact with connecting pads 13 of the heater element 8. On the opposite side of the spring 18, at least one preferably two protrusions 6 are placed. The protrusion 6 is on the spring 18 and in direct contact with electrical contacting element 7 which are placed on the lens holder body 5. On the lens holder body 5 at least one busbar 9 which is extruded from the inner surface of the lens holder body 5 serve as a contact with the circuit board 17.

[0089] The inner surface of the spring 18 is insulated with an insulation material and the spring 18 is conductive to supply electric energy to the heater 8. The spring 18 on the lens housing 4 covers the lens housing 4 in a ring shaped form or more preferably 360 degree form. The ring-shaped form may be either a closed loop or an open ring that is not connected from one end to the other.

[0090] The electrical contacting elements 7 are overmolded at the contacting surface of the lens holder body 5 with an insulating material.

[0091] Said insulating materials may be chosen from plastic, rubber, silicone, epoxy resin, polyurethane, thermoplastic elastomer (TPE), polyvinyl chloride (PVC), polycarbonate, fluoropolymer or any other insulating material.

[0092] The electrical contacting element 7 is a ring shaped form preferably forming a 360 degree contact surface within the lens holder body 5 to ensure the spring 18 is always in contact position with the electrical contacting elements 7. The ring-shaped form may be either a closed loop or an open ring that is not connected from one end to the other.

[0093] The circuit board 17 comprises supply circuitry for supplying the electrical current to the heater element 8. To this end, the circuit board 17 may carry a corresponding power source 2023PF03217 or circuitry, in particular conductive paths or wires, for connecting the heater element 8 to an external power source. The external power source may, for example, be located in the control unit 3 or may be connected to the camera 2 via the control unit 3.

[0094] As shown in figure 4 the heater element 8 is placed on the upper surface of the internal barrel 10. Internal barrel 10 also contains the lens module. Lens module is covered with a protective cover 15 which is placed over external barrel 11. An O-ring 19 is placed on the external barrel 11, with the protective cover 15 positioned on top of it. When the O-ring 19 seal is compressed, the protective cover 15 component rests on the heater, with the heater element 8 facing the protective cover 15. A cap 14 is threaded onto the external barrel 11, and thread lock is applied during the assembly process. The threading continues until the protective cover 15 reaches the hard stop flange of the internal barrel 10, where the heater element 8 is adhesively assembled. At this point, the O-ring 19 seal is compressed to the desired height.

[0095] Reference numbers:

[0096] 1 Motor vehicle

[0097] 2 Camera

[0098] 3 Control Unit

[0099] 4 Lens housing

[0100] 5 Lens holder body

[0101] 6 Protrusion

[0102] 7 Electrical contacting element

[0103] 8 Heater element

[0104] 9 Busbar

[0105] 10 Internal barrel

[0106] 11 External barrel

[0107] 12 Extension

[0108] 13 Connecting Pad

[0109] 14 Cap

[0110] 15 Protective cover

[0111] 16 Rear housing body

[0112] 17 Circuit board.

[0113] 18 Spring

[0114] 19 O-ring

Claims

2023PF03217Claims1. Camera for a motor vehicle, the camera comprising at least one circuit board (17), a lens housing (4), a lens holder body (5) which is mechanically connected to the lens housing (4), a heater element (8) for heating a lens module inside the lens housing (4), at least one electrical contacting element (7) which is arranged at a surface of the lens holder body (5) and electrically connected to the circuit board characterized in that the at least one electrical contacting element (7) is fitted at an inner surface of the lens holder body (5) and an at least one spring (18) is fitted around the lens housing (4) such that the electrical contacting element (7) is electrically connected to the spring (18) when the lens holder body (5) is mechanically connected to the lens housing (4).

2. The camera according to claim 1, characterized in that the contacting surface to the lens holder body (5) of the at least one electrical contacting element (7) is electrically insulated.

3. The camera according to claim 1, characterized in that the contacting surface of the at least one spring (18) to the lens housing (4) is insulated.

4. The camera according to claim 3, characterized in that the at least one spring (18) on the lens housing (4) covers the lens housing (4) in a ring shaped form.

5. The camera according to claim 3, characterized in that the at least one spring (18) comprises at least one electrical connecting element in form of a protrusion (6).

6. The camera according to claim 2, characterized in that the at least one electrical contacting element (7) is overmolded at the contacting surface of the lens holder body (5) with an insulating material.

7. The camera according to claim 2, characterized in that the at least one electrical contacting element (7) is in a ring shaped form within the lens holder body (5).2023PF032178. The camera according to claim 1, characterized in that the lens housing (4) comprises an internal barrel (10) and an external barrel (11) wherein the heater element (8) is placed on the top surface of the internal barrel (10).

9. The camera according to claim 8, characterized in that the heater element (8) has an extension (12) to supply power to the heater (8) wherein the extension (12) is placed between the internal barrel (10) and the external barrel (11).

10. The camera according to claim 8 or 9, characterized in that the internal barrel (10) comprises at least one cavity slot to allow the heater extension (12) to be placed inside the slot.

11. The camera according to claim 10, characterized in that the extension (12) has at least one connecting pad (13) to electrically connect the extension (12) to the at least one spring (18).

12. The camera according to claim 1, characterized in that the heater element (8) is a flexible heater.

13. The camera according to claim 1, characterized in that the lens holder body (5) comprises a busbar (9) extruded from the at least one electrical contacting element (7).

14. Electronic vehicle guidance or advanced driving assisiting system comprising at least one camera (2) according to one of the preceding claims.

15. Method for heating a lens module of a camera (2) for a motor vehicle (1), characterized in that the camera comprising at least one circuit board (17), a lens housing (4), a lens holder body (5) which is mechanically connected to the lens housing (4), a heater element (8) for heating a lens module inside the lens housing (4), at least one electrical contacting element (7) which is arranged at a surface of the lens holder body (5) and electrically connected to the circuit board wherein the at least one electrical contacting element (7) is fitted at an inner2023PF03217 surface of the lens holder body (5) and an at least one spring (18) is fitted around the lens housing (4) such that the electrical contacting element (7) is electrically connected to the spring (18) when the lens holder body (5) is mechanically connected to the lens housing (4).

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