WO2020200814A1

WO2020200814A1 - Method for arranging an optical device and camera device

Info

Publication number: WO2020200814A1
Application number: PCT/EP2020/057625
Authority: WO
Inventors: Andreas Kugler; Martin Winkler; Alexander Fischer; Istvan Denes; Ulrich Seger
Original assignee: Robert Bosch Gmbh
Priority date: 2019-04-03
Filing date: 2020-03-19
Publication date: 2020-10-08
Also published as: DE102019204761A1

Abstract

The invention relates to a method for arranging an optical device (22) relative to an image-capturing device (14), cooperating with the optical device (22), on a circuit carrier (10), wherein the optical device (22) is positioned relative to the image-capturing device (14) in a target position (SP) and then the two devices (14, 22) are fixed relative to one another in the target position (SP), wherein the optical device (22) has first manufacturing-related tolerances (T₂₂) and the image-capturing device (14) has second manufacturing-related tolerances (T₁₄), which are taken into account in the positioning of the two devices (14, 22) in the target position (SP).

Description

description

Method for the arrangement of an optical device and camera device

Technical area

The invention relates to a method for arranging an optical device to form an image-recording device that interacts with the optical device, as can be used in particular as a component of a driver assistance system in a vehicle. The invention also relates to a method for producing a printed circuit board with a plurality of circuit carriers and a camera device with an optical device and an image-recording device.

State of the art

DE 10 2014 220 519 A1 by the applicant discloses a method for arranging an optical device with the optical device

cooperating, image-recording device with the features of the preamble of claim 1 known. The optical device is a lens system and the image recording device is an imager, which together form a component of a camera, for example a camera in a driver assistance system in a vehicle.

When assembling the image-generating parts of the camera, it is essential that the optical device is in a defined position for the image-taking

Position facility. The defined position is important because the recorded images should have a certain quality so that their image data can be processed, for example, in the context of a driver assistance system. For this purpose, it is necessary to move the lens system in relation to the light-sensitive surface of the imager both in the three spatial axes and in relation to three tilt axes which are spatially perpendicular to one another to position. This is done with the one known in the cited document

Method already using a modified, a shorter set-up time

required method, the method providing for the quality of the image generated by the lean to be compared with a test image or image data of a test image. The optical device is positioned or fixed in relation to the image-receiving device, in particular, by means of a UV-curing adhesive, for example, although not yet

Once the adhesive has cured, the lens system can be moved to the required target position. In the known method, it is essential that the two devices are positioned and fixed to one another by an active positioning process of the lens system with simultaneous evaluation of image data from the imager. This makes it necessary for the imager to be preassembled and electrically connected to an evaluation device at least to the extent that its captured image data can be evaluated. The active positioning process of the optical

The device for the image-recording device is required because of the different tolerances or properties of the imager and the lens system, which are largely production-related.

A further method with the features of the preamble of claim 1 is also known from DE 10 2016 221 664 A1. Although it is mentioned there that production-related tolerances of the components are taken into account, these production-related tolerances only cause a

Pre-positioning of a component is adapted to its existing tolerances. In the case of camera systems in particular, however, it is mentioned that an active setting process of the devices (with evaluation of image data) to one another is also provided.

Disclosure of the invention

The method according to the invention for arranging an optical device to form an image-recording device interacting with the optical device and having the features of claim 1 has the advantage that it can be used without the active alignment process provided in the production line when the optical device is assembled with the image-recording device which requires an active evaluation of data from the imager. As a result, the positioning and fixing method according to the invention takes place particularly quickly and therefore inexpensively.

The invention is based on the idea of reducing production-related tolerances of both the optical device and the image-recording device

to precisely record upstream processes and to determine a target position of the devices to each other using an algorithm on the basis of the recorded production-related tolerances, in which it is ensured with sufficient certainty that images with the desired quality through the

image-receiving device can be generated. The method according to the invention also makes it possible in principle to be able to make pairings between the individual devices with knowledge of the production-related tolerances of both the optical device and the image-recording device, for example in such a way that the production-related tolerances of the respective device are at least partially equalized. This has the advantage that the target positions of the optical device in relation to the image-recording device change only relatively little during the ongoing production. In particular, this also has the advantage that, for example, the amount of auxiliary materials, in particular adhesives, which on the one hand serves to fix the two devices to one another in the cured state and on the other hand enables the desired tolerance compensation to achieve the target position, can be reduced.

Against the background of the above considerations, the teaching of the invention according to claim 1 therefore proposes that the target position of the two devices is determined using an algorithm taking into account the first and second manufacturing tolerances of the two devices, and that an actual position of the Optical device for the image-recording device is detected by means of a measuring system in order to set the target position by means of a handling device. The measuring system thus serves to control or ensure the desired position of the optical device in relation to the image-recording device determined by means of the algorithm on the basis of the recorded actual position. Advantageous developments of the method according to the invention are listed in the subclaims.

In order to achieve the best possible quality of the images generated by the image-taking device or to be able to optimally compensate for the manufacturing-related tolerances of the devices, it is provided that the target position is a position defined by three perpendicular spatial axes and three perpendicular tilting axes .

An auxiliary material, in particular a heat-conducting adhesive or a solder, is preferably used to fix the optical device to the image-recording device in the desired position, the auxiliary material not yet being used

cured state allows a positioning of the two devices to each other within certain tolerances. This makes it possible, in particular, to use one and the same amount of auxiliary material to enable different positioning of the optical device in relation to the image-recording device in order to compensate for the manufacturing-related tolerances. There are also no, for example, a certain thickness or the like due to the auxiliary. having spacer elements or the like. required. There is also no mechanical connection process in the sense of a screw connection or the like. required between facilities. In particular, if a thermally conductive adhesive is used as an auxiliary material or a solder, an improved heat transfer of the elements of the devices for

Allows circuit carrier, which on the one hand reduces thermal stresses, and on the other hand also counteracts expansion of the components through temperature compensation, which could possibly deteriorate the quality of recorded images due to the changed geometry.

In a further development of the last proposal made when using an auxiliary substance, it is provided that the amount of auxiliary substance is below

Consideration of the target position of the devices is dosed. In this way, only that amount of auxiliary material is used which, on the one hand, enables the components or devices to be aligned with one another in the not yet hardened state of the auxiliary substance, and which, on the other hand, ensures the required firm connection. It can also be provided in a further development of the fixation, in addition to the auxiliary substance, solid particles or elements or the like. to be used to set the target position. This is particularly advantageous if the auxiliary would otherwise have to be applied in a relatively large layer thickness or in order to optimize other specific properties, for example heat transfer.

The method according to the invention, which has basically been described so far, assumes that the algorithm uses the tolerances of the two devices to determine an optimal target position. However, other circumstances can possibly also influence the quality of the images of the image-recording device, for example the accuracy with which the desired position can be maintained by appropriate devices. For example, results in a

Wear on the manufacturing device for positioning or setting the target position of the optical device relative to the image recording device results in a deviation of the actual position from the target position, which can lead to poor quality recordings or images. In order to avoid such influences or to optimize the actual position relative to the target position

allow, a further preferred method provides that the optical device and the image recording device after their positioning and fixing to a camera unit or the like. be completed that preferably randomly the quality of the images generated by the image recording unit is assessed, and that based on the assessed quality of the images generated and taking into account the first and second tolerances of the two devices and the actual position of the two devices to each other of the camera unit examined or similar the algorithm for determining the target position is adapted in the case of devices that are not yet arranged in relation to one another.

Furthermore, the invention also comprises a method for producing a printed circuit board panel with a plurality of circuit carriers, each circuit carrier having at least one optical device and one

having image-recording device, which are positioned relative to one another on the printed circuit board using a method according to the invention as described so far. Such a circuit board benefit has the advantage that under a production-engineering perspective, without having to evaluate the data from the image-recording devices, they may not even be in this state are connected to corresponding components, the positioning of the optical device to the image receiving device is made possible.

In a further development of the method described last, it is provided that before the positioning and fixing of the optical device, the

image-receiving device is connected to the circuit carrier, preferably using a further adhesive or solder layer, that the image-receiving device is then connected to an electrically conductive structure of the circuit carrier, and that the optical device is then positioned and fixed to the image-receiving device.

The invention further comprises a camera device comprising an optical device and an image-recording device, the two devices being positioned and fixed to one another according to a method according to the invention.

In particular, the optical device comprises a lens system with at least one lens, which is connected to a circuit carrier by means of a lens holder connected to the at least one lens with the interposition of an auxiliary material, as well as with an image-recording device designed as an imager, which is also connected to the

Circuit carrier is connected.

Further advantages, features and details of the invention emerge from the following description of preferred exemplary embodiments and with reference to the drawings.

Brief description of the drawings

1 shows a partial area of a circuit carrier with an image-recording device and optical device arranged thereon in a simplified longitudinal section. FIG. 2 shows a flowchart to explain the essential method steps for positioning and fixing the optical device for the image-recording device on the circuit carrier according to FIG. 1,

3 shows a schematic representation of a plurality of

Circuit carriers having printed circuit board panels and

FIG. 4 shows a further flow chart to explain the essential steps in the production of the printed circuit board panel according to FIG. 3.

Embodiments of the invention

The same elements or elements with the same function are provided with the same reference numbers in the figures.

In Fig. 1, a circuit carrier 10 is a detail in the form of a

Substrate or a circuit board shown in detail. On the upper side of the circuit carrier 10, the latter has an imager 12 as an image-recording device 14 and an electrically conductive structure 16, for example in the form of conductor tracks or the like. The electrically conductive structure 16 is preferably also provided on the underside and, if necessary, in intermediate layers of the circuit carrier 10, the individual structures 16 using vias or the like in a known manner. can be connected. The imager 12 is connected to the circuit carrier 10 in the area of the electrically conductive structure 16 with an auxiliary material 18 interposed, in particular in the form of an adhesive or solder layer. Furthermore, the imager 12 is exemplarily above

Wire bond connections 20 are connected to other regions of the electrically conductive structure 16.

The imager 12 is in operative connection with an electronic circuit or the like via the electrically conductive structure 16. connected, which the electrical pulses generated by the imager 12 due to the incidence of light in images or

Image data transformed (not shown). As this process is known per se and is not essential to the invention, will not be discussed further in this regard.

Above the imager 12 is an optical one in operative connection therewith

Device 22 arranged. The optical device 22 comprises, for example, a one-part or multi-part lens holder 24 which is designed to attach at least one lens 25, in the illustrated embodiment three lenses 25, of a lens system 26. The at least one lens 25 or the lens system 26 can, for example, have been connected to the lens holder 24 by overmolding when the lens holder 24 is designed as a plastic injection-molded part.

The exemplary cup-shaped lens holder 24 has on the side facing the circuit carrier 10 a contact surface 30 that runs radially around a longitudinal axis 28 and is connected to the top of the circuit carrier 10 with an auxiliary material 32 with a thickness d in between. The auxiliary material 32, which is preferably designed as a UV-curing adhesive or as a solder layer, enables positioning or relative movement of the optical device 22 or the lens system 26 to the surface of the imager 12 in a not yet cured or solid state, and on the other hand serves in the cured state of the auxiliary material 32 of the fixation of the optical

Device 22 or of the lens system 26 in a nominal position SP to the imager 12. The nominal position SP of the optical device 22 to the imager 12 or to the image recording device 14 is characterized by nominal positions in three perpendicular spatial axes x, y and z and about three tilting axes k _x , k _y and k _z arranged perpendicular to one another. In particular, the target position SP of the optical device 22 relative to the imager 12 results from the fact that the imager 12 or the image-recording device 14

Image data are to be generated which, for example, map the images of the surroundings projected by the lens system 26 onto the imager 12 as truthfully as possible or must have a certain minimum quality. This against the background that the elements described so far are preferably part of a camera 35, which can be used, for example, in a driver assistance system of a vehicle to record the environment. Both the imager 12 and the lens system 26 or the optical

Device 22 have manufacturing-related tolerances Ti ₂ or T22, which occur during the manufacture of optical device 22 or imager 12

corresponding test facilities can be detected. In the simplest case, these tolerances T12 and T22 can be geometric deviations from the ideal dimensions of the components, or, for example, functional tolerances, e.g. with regard to the focal position of the lens system 26.

For positioning the optical device 22 for image recording

Device 14 or for imager 12 has a manufacturing device in addition to a handling device 34, shown only schematically, which is used for this purpose

is designed to position the optical device 22 or the lens holder 24 in the desired position SP to the imager 12 and a measuring system 36, for example an optical one on laser beams or the like. based measuring system 36, in order to control compliance with the desired position SP of the optical device 22 to the image-recording device 14 or to the imager 12. To this end, it is necessary to also know or detect the actual position of the image recording device 22, which is either done by means of the measuring system 36 or in some other way. Further, the manufacturing apparatus comprises a control device 38, or the measurement system 36 is disposed in operative connection with the handling device 34 to the target position SP of the optical device 22 to the image receiving means 14 on the basis of which _is the present position detected by the measuring system 36 P the optical device 22 to set.

The control device 38 includes an algorithm 40 which, in particular, knowing the tolerances T12 and T22 of the image recording device 12 or the optical device 22, which are fed to the control device 38 or the algorithm 40 as input variable, the required target position SP of the optical Device 22 for image-recording device 14 is calculated in order to ensure the desired quality of the image data or images that are generated by imager 12. The control device 38 thus calculates the target position SP and controls the handling device 34 in accordance with the detected actual position P _ist in order to control the optical device 22 or the

Position the lens system 26 in the desired position SP in relation to the image-recording device 14. Furthermore, the control device 38 controls a Dosing device 42 for dosing a certain amount of auxiliary material 32. As long as the auxiliary material 32, for example adhesive or solder, is not yet hardened or solid, the handling device 34 can use the optical

Position device 22 in target position SP. Compliance with the target position SP must be guaranteed until the auxiliary material 32 has hardened.

Should it emerge from cameras 50 that have already been manufactured that the target position for these cameras 50 is not optimal with regard to the optimal quality of image data or images from the imager 12, then the algorithm 40 can also modify this via a correction value KW that not only the tolerances Ti ₂ and T22 of current optical devices 22 or image recording devices 12 are taken into account when calculating the target position SP, but also other influences that lead to a deviation in the quality of the image data generated in cameras 50 that have already been manufactured have led.

In FIG. 2, the essential method steps for positioning the optical device 22 in relation to the image-recording device 14 are explained as follows: In a first step 101, the tolerances T12 and T _{22 of} the

image-recording device 14 and the optical device 22 determined. In a second step 102, the tolerances Ti ₂ and T _{22 are} fed to the algorithm 40 as an input variable. In the third step 103, the algorithm 40, possibly taking into account a correction value KW, calculates the target position SP of a special optical device 22 for a special image-recording device 14 on the basis of the tolerances Ti ₂ and T ₂₂ and possibly the

Correction value KW. In a fourth step 104, both the

Metering device 42 is controlled in order to meter a certain amount of auxiliary material 32, as well as the handling device 34 for positioning the optical device 22 in the desired position SP. At the same time, knowing the actual position of the image recording device 14 on the circuit carrier 10, the measuring device 36 is switched into operative connection with the handling device 34 such that the target position SP between the devices 14, 22 can be maintained with the desired tolerances. 3 shows a printed circuit board 50 which comprises a plurality of circuit carriers 10 as described above, which are arranged next to one another without gaps within the printed circuit board 50, and which, after their manufacture, are separated or isolated from one another, in particular by cutting or sawing will. Furthermore, an image-recording device 14 or an imager 12 as well as an optical device 22 can already be seen in the area of each circuit carrier 10. With a view to the production of such a printed circuit board 50, the flowchart according to FIG. 4 is discussed below. It can be seen there that, in a first step 201, the image-recording device 14 or the imager 12 is interposed with the auxiliary material 18 or solder with the respective

Circuit carrier 10 are connected. Then, in a second step 202, the connections between the respective imager 12 or the respective image-recording device 14 and the respective

Circuit carrier 10 produced. In a third step 203, the respective individual positioning and fixing of the optical device 22 in its respective desired position SP relative to the respective image-recording device then follows

Device 14 on the basis of the respective tolerances Ti ₂ , T22, as is the case on the basis of a single circuit carrier 10 or a single image-recording device

Device 14 and an optical device 22 was explained above.

Subsequently, in a fourth step 204, the individual circuit carriers 10 are separated from the printed circuit board 50. Finally, in a fifth step 205, further equipping or assembly of the takes place

Circuit carrier 10 to a camera 50.

The methods described so far or the circuit carrier 10 and the image-recording device 14 and the optical device 22 can be modified or modified in many ways without deviating from the inventive concept.

Claims

Expectations

1. A method for arranging an optical device (22) to form an image-receiving device which cooperates with the optical device (22)

Device (14) on a circuit carrier (10), in which the optical device (22) is positioned in relation to the image-recording device (14) in a desired position (SP) and then the two devices (14,

22) are fixed to each other in the target position (SP), the optical device (22) having first production-related tolerances (T22) and the image-recording device (14) having second production-related tolerances (T14) which, when the two devices are positioned ( 14, 22) are taken into account in the target position (SP), characterized in that the target position (SP) of the two devices (14, 22) using an algorithm (40) including the first and second

Manufacturing tolerances (T14, T22) is determined, and that an actual position (P, _st ) of the optical device (22) to the image-recording device (14) is detected by means of a measuring system (36) to determine the target position (SP) by means of a handling device (34).

2. The method according to claim 1,

characterized,

that the target position (SP) one through three perpendicular to each other

arranged spatial axes (x, y, z) and three mutually perpendicular tilting axes (k _x , k _y , k _z ) is a defined position.

3. The method according to claim 1 or 2,

characterized,

that an auxiliary material (32), in particular a heat-conducting adhesive or solder, is used to fix the two devices (14, 22) in the desired position (SP), and that the auxiliary material (32) is not yet hardened or fixed state enables the two devices (14, 22) to be positioned relative to one another in the desired position (SP).

4. The method according to claim 3,

characterized,

that the amount of auxiliary substance (32) is dosed taking into account the target position (SP).

5. The method according to claim 3 or 4,

characterized,

that in addition to the auxiliary (32) solid particles, elements or the like. to

Setting the target position (SP) can be used.

6. The method according to any one of claims 1 to 5,

characterized,

that the optical device (22) and the image-recording device (14) after their positioning and fixing to a camera (35) or the like.

be completed that the quality of the images generated by the image recording device (14) is assessed, preferably randomly, and that based on the assessed quality of the images generated and taking into account the first and second tolerances (T i ₄ , T22) of the two devices (14, 22) and the actual position (P _ist ) of the two devices (14, 22) to one another of the examined camera (35) or the like. the algorithm (40) for determining the target position (SP) is adapted by means of a correction value (KW) when devices (14, 22) are still to be arranged in relation to one another.

7. A method for producing a printed circuit board panel (50), with a plurality of circuit carriers (10), wherein each circuit carrier (10) has at least one optical device (22) and an image-receiving device (14) which, according to a method according to one of the claims 1 to 6 are positioned relative to one another on the printed circuit board panel (50).

8. The method according to claim 7,

characterized, that prior to the positioning and fixing of the optical device (22), the image-receiving device (14) is connected to the circuit carrier (10), preferably using an adhesive or solder layer as auxiliary material (18), that the image-receiving device (14) is then connected to an electrically conductive structure (16) of the circuit carrier (10) is connected, and that the positioning and fixing of the optical device (22) to the image-recording device (14) in the target position (SP) then takes place.

9. A camera (35) comprising an optical device (22) and a

Image-recording device (14) which are positioned and fixed with respect to one another according to a method according to one of Claims 1 to 6.

10. Camera according to claim 9,

characterized,

that the optical device (22) comprises a lens system (26) with at least one lens (25) which is connected to a circuit carrier (10) by means of a lens holder (24) connected to the at least one lens (25) with an auxiliary material (32) in between and to an image-recording device (14) designed as an imager (12) which is connected to the circuit carrier (10) using a further auxiliary material (18).