Method of manufacturing a camera module and method of using a contact member

Abstract

The present invention relates to a method for manufacturing a camera module (1) having a lens (2) incorporating a heating device, and a housing (3) including a circuit board (4) and an imaging element (5), the method comprising the steps of: - inserting said lens (2) into said housing (3); - aligning the lens (2) with respect to the imaging element (5); - fixing said lens (2) by establishing an adhesive connection (6) with said housing (3); - by releasing and / or by actuating, in particular by thermal or electrical actuation, a clamping device (8) to electrically contact a heating device integrated in said lens (2) by means of a biased and / or actuable, in particular thermally or electrically actuable, contact member (7) in electrically conducting contact with a contact surface (9) arranged on the outer periphery of said lens (2); The present invention relates to a method comprising the steps of: The present invention also relates to a method of using the contact member.

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a camera module having a lens with an integrated heating device and a housing with a circuit board and an image sensor. The camera module can be used in particular in motor vehicles, for example for monitoring the environment of the motor vehicle.

[0002] Also described is the use of a contact member to make electrical contact with a heating device incorporated within the lens of a camera module. [Background technology]

[0003] Camera modules used for environmental monitoring are subject to environmental influences and can cause condensation and / or ice to form on the optical lenses of the lens. In such cases, there is a risk that the image sensor of the camera module cannot receive a signal or that the quality of the received signal is reduced. This must be avoided, for example, by means of a heating device integrated into the lens.

[0004] The heating device integrated in the lens needs to be electrically contacted. For this, contact elements can be used, which establish a connection between the heating device and a circuit board of the camera module accommodated in the housing. Since the accessibility of the contact elements and the circuit board is not guaranteed after bonding of the camera module, especially after the lens is inserted in the housing, the electrical contact of the heating device is usually made before or during insertion. The use of flexible contact elements, for example foil conductors or cables, makes it possible to compensate for tolerances, for example for aligning the lens with respect to the image sensor. The use of flexible contact elements also has the advantage that the adhesive connection remains at least approximately force-free during the subsequent bonding of the lens to the housing. However, it has been found that the use of flexible or bendable foil conductors or cables has the disadvantage that the achievable bonding speed is limited. Summary of the Invention [Problem to be solved by the invention]

[0005] The object of the present invention is therefore to make the electrical contact of a heating device integrated in a lens more reliable and at the same time easier. This object is achieved by a method for producing a camera module as claimed in claim 1 and by a method for use as claimed in claim 6. [Means for solving the problem]

[0006] The proposed method is for manufacturing a camera module having a lens with an integrated heating device and a housing with a circuit board and an image sensor. - inserting the lens into the housing; - aligning the lens with respect to the imaging element; - fixing the lens by establishing an adhesive connection with the housing; - by releasing and / or by actuating, in particular by thermal or electrical actuation, the clamping device, bringing into electrical contact with a heating device integrated in the lens by means of a biased and / or actuable, in particular thermally or electrically actuable, contact member in electrically conducting contact with a contact surface arranged on the outer periphery of the lens; Includes.

[0007] As a result, the heating device integrated into the lens makes electrical contact only after the lens has been inserted, aligned and fixed relative to the housing, i.e. when the adhesive connection used to fix the lens has hardened enough to absorb forces, so that the adhesive connection and the position of the lens relative to the imager remain unaffected by the electrical contact of the heating device, which has yet to be made.

[0008] Electrical contact of the heating device after the lens has been inserted, aligned and fixed in the housing is made possible by the proposed use of biased and / or actuatable contact members, in particular thermally or electrically actuatable, since the contact members can abut against a contact surface provided on the lens by releasing and / or actuating the clamping device, in particular by thermally or electrically actuating, i.e. the abutment is made without contact, so that lack of accessibility of the contact members is not an issue.

[0009] Preferably, for carrying out the proposed method, contact elements are used which are configured as spring arms, with which the distance between the heating device and the circuit board can be bridged in a simple manner, and contact elements which are configured as spring arms can also be biased in a simple manner by means of a clamping device.

[0010] Also preferably, diametrically opposed contact elements are used on the lens, which can in this case be radially biased by means of a clamping device, and upon release of the clamping device, the contact elements automatically come into contact with contact surfaces provided on the lens, which for this purpose are preferably arranged on the lens in a suitable manner, i.e. so as to be diametrically opposed.

[0011] It is further proposed that the contact element is electrically conductively connected, preferably welded or soldered, at its other end, i.e. the end opposite the contact surface of the lens, to the circuit board. The contact element and the circuit board may thus constitute a pre-assembled unit. This allows pre-assembly to take place before the lens is inserted into the housing, facilitating visual inspection of the conductive connection of the contact element to the circuit board.

[0012] According to a first preferred embodiment of the invention, a contact member is used which is biased by means of a clamping device, by releasing the clamping device the contact member abuts against the contact surface of the lens.

[0013] For this purpose, the clamping device may be configured in a hook-like or ring-like manner at least in some areas, by means of which the biased contact member can be held until the lens has been inserted into the housing, aligned with respect to the imaging element and fixed by means of an adhesive connection.

[0014] If the clamping device is configured in a hook-like manner in at least some areas, the clamping device may be in locking engagement with at least one contact member. The clamping device can be released by unlocking. The clamping device preferably includes a plurality of hook members, more preferably the number of hook members corresponds to the number of contact members to be actuated.

[0015] If the clamping device is configured annularly in at least some areas, it may be arranged to hold the contact member at a distance relative to a contact surface provided on the lens. Preferably, the clamping device comprises at least one ring that is axially displaceable relative to the contact member. The ring is then axially displaced to release the clamping device.

[0016] Alternatively or additionally, it is proposed to use a clamping device that is manufactured, at least in some areas, from a bimetal, a shape-memory material, for example a shape-memory alloy or a shape-memory polymer, or from a contracting material. The clamping device can thus be activated or released from the outside, i.e. without contact. For example, by activating a first part of the clamping device, in particular by thermal or electrical activation, a deformation of this part can be caused, which then induces a movement of a further part of the clamping device, for example an axially displaceable ring.

[0017] Thus, the clamping device used to bias the contact members is preferably released by displacement and / or actuation, in particular by thermal or electrical actuation.

[0018] According to a further preferred embodiment of the invention, an actuatable contact element is used, in particular actuatable by heat or electricity, which is manufactured at least in some areas from a bimetal, a shape memory material, for example a shape memory alloy or a shape memory polymer, or a contracting material. In this case, no separate clamping device is required for biasing the contact element, since the contact element itself is actuatable, in particular actuatable by heat or electricity, to create an electrical contact. The actuation of the contact element causes a deformation, which brings the contact element into contact with the contact surface of the lens. This deformation is preferably achieved in only one direction, so that the electrical contact of the heating device thus created is permanent. That is to say, preferably, a material is used which retains its shape after deformation and does not return to its original shape.

[0019] For example, a fusible wire may be used as the thermally or electrically actuable contact member, which after thermal or electrical actuation establishes an electrically conductive contact with the contact surface of the lens.

[0020] Furthermore, for electrical contact with a heating device integrated in the lens of the camera module, the use of a contact element is proposed, at least in a part of its area made of a bimetal, a shape-memory material, for example a shape-memory alloy or a shape-memory polymer, or a shrinking material, and one end of which is electrically conductively connected, preferably welded or soldered, to a circuit board, which allows for a more reliable electrical contact of the heating device in a simple manner. [Brief description of the drawings]

[0021] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. [Figure 1] 1 is a schematic longitudinal section of a camera module which can be produced by a first method according to the invention; [Diagram 2] FIG. 2 is a partially enlarged view of FIG. [Diagram 3]4 is a schematic longitudinal sectional view of a camera module that can be manufactured by a second method according to the present invention; FIG. [Figure 4] 4 is a schematic longitudinal section of a camera module which can be produced by a third method according to the invention. [Diagram 5] FIG. 11 is a schematic longitudinal sectional view of a camera module that can be manufactured by a fourth method according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] FIG. 1 shows a camera module 1 having a lens 2 with an integrated heating device (not shown). For electrical contact of the heating device, two contact surfaces 9 are provided on the outer periphery of the lens 2, which are diametrically opposed on the lens 2. The lens 2 is inserted into the housing 3 such that the contact surfaces 9 are located inside the housing 3. Furthermore, the lens 2 is glued to the housing 3 via a glued connection 6. The glued connection 6 can only be established after the lens 2 has been aligned with respect to the imaging element 5 accommodated in the housing 3. Now the lens 2 is moved or pivoted in different directions x, y, z. To allow these movements, the heating device integrated in the lens 2 is only electrically contacted after the lens 2 has been aligned and the glued connection 6 has been established.

[0023] In FIG. 1, the electrical contact is established via two diametrically opposed contact elements 7 on the lens 2, which are electrically connected at their other ends to the circuit board 4 housing the image sensor 5. As can be seen in particular from FIG. 2, the contact elements 7 are configured as spring arms that can be biased by means of a clamping device 8 so that a distance from a contact surface 9 provided on the lens 2 is maintained. For this purpose, the clamping device 8 has two spring-arm-like elements that are arranged radially outwardly with respect to the contact elements 7 and have hook elements 10 at their free ends. These can be engaged with the contact elements 7 (see dashed lines for the contact elements 7') so as to hold the contact elements 7, preferably until the adhesive connection 6 between the lens 2 and the housing 3 has hardened. When the clamping device 8 is then released, the biased contact elements 7 come into contact with the contact surfaces 9 of the lens 2 and the electrical contact of the heating device is established.

[0024] 3 shows a further camera module 1, which includes a lens 2 with an integrated heating device (not shown). Here again, only the contact surfaces 9 on the outer periphery of the lens 2 are shown for electrically contacting the heating device. Likewise, the housing 3 of the camera module 1, which is constructed similarly to the housing 3 of the camera module 1 of FIG. 1 and is connected to the lens 2 via a glued connection 6, is not shown.

[0025] 3 shows a contact member 7 configured as a spring arm, which can be brought into contact with a contact surface 9 provided on the lens 2 by releasing a clamping device 8. For this, the clamping device 8 has an axially displaceable ring 11 (see arrow), which is held by a bracket 12 in a position in which it holds the contact member 7 at a distance from the contact surface 9. The bracket 12 is made of a material which can be deformed by being actuated by heat or electricity. The deformation of the bracket 12 leads to an axial displacement of the ring 11, which releases the clamping device 8 and brings the contact member 7 into contact with the contact surface 9 (see dotted line).

[0026] Figure 4 shows a modification of the clamping device 8 shown in Figure 3. Instead of the bracket 12, an actuatable thin wire-like member 13 causes the displacement of the ring 11. The wire-like member 13 is tensioned between the ring 11 and a fixed base 15. When actuated, the length of the wire-like member 13 shortens, causing the displacement of the ring 11. A locking member 14 prevents unintentional displacement of the ring 11 before the wire-like member 13 is actuated.

[0027] The further camera module 1 shown in Fig. 5 can be produced particularly simply by the method according to the invention. The illustration in Fig. 5 is limited to the main components for carrying out the method, namely the lens 2 with its peripheral contact surface 9 and the contact element 7 connected to the circuit board 4. The contact element 7 is produced from a material which can be activated in particular by heat or electricity, for example a shape-memory material. As a result of the activation of the material, the contact element 7 is deformed and comes into contact with the contact surface 9 after the deformation.

Claims

1. A method for manufacturing a camera module (1) having a lens (2) incorporating a heating device, and a housing (3) including a circuit board (4) and an imaging element (5), comprising the steps of: - inserting said lens (2) into said housing (3); - aligning said lens (2) with respect to said imager (5); - fixing said lens (2) by establishing an adhesive connection (6) with said housing (3); - by releasing and / or activating a clamping device (8), bringing into electrical contact with a heating device integrated in said lens (2) by means of a biased and / or actuatable contact member (7) in electrically conducting contact with a contact surface (9) arranged on the outer periphery of said lens (2); A method comprising:

2. 2. A method according to claim 1, characterized in that the clamping device (8) is released and / or activated by heat or electricity.

3. 3. The method according to claim 1 or 2, characterized in that contact elements (7) configured as spring arms and / or diametrically opposed on the lens (2) are used, said contact elements (7) being in an electrically conductive connection with the circuit board (4).

4. 4. The method according to claim 3, wherein the contact members (7) and the circuit board (4) are electrically conductively connected by welding or soldering.

5. A contact member (7) is used that is biased by the clamping device (8), and the clamping device (8) is configured to: - configured in the form of a hook or ring, and / or characterised in that it is made from a bimetal, a shape memory material or a shrinking material, The method according to any one of claims 1 to 4.

6. The method of claim 5, wherein the shape memory material is a shape memory alloy or a shape memory polymer.

7. Method according to any one of the preceding claims, characterised in that the clamping device (8) is released by displacement and / or actuation.

8. 8. The method according to claim 7, characterized in that the clamping device (8) is displaced and / or actuated thermally or electrically.

9. 5. The method according to claim 1, characterized in that an actuatable contact member (7) is used, said contact member (7) being made, at least in some areas, from a bimetal, a shape memory material or a shrinking material.

10. 10. The method according to claim 9, characterized in that the contact member (7) is thermally or electrically actuatable.

11. 11. The method according to claim 9 or 10, characterized in that the shape memory material is a shape memory alloy.

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