JP2018013623A - On-vehicle imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle imaging device capable of accurately adjusting an optical axis of an imaging unit with respect to a housing while suppressing precise processing to the housing as much as possible.SOLUTION: A stereo camera 20 mounted on a vehicle 100 includes: camera modules 1A and 1B having a lens 6B and an imaging element 7A; and a stay 3 for holding the camera modules 1A and 1B. The stay 3 and camera modules 1A and 1B are fixed by an adhesion layer 13 without engagement. The fixation is kept in the state in which the optical axis between the camera module 1A and camera module 1B and the optical axis between the camera modules 1A and 1B and the stay 3 are adjusted accurately.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an in-vehicle imaging device that acquires a captured image from an imaging element.

  For the purpose of improving the productivity of the camera unit and improving the durability of the camera unit by reducing the number of components of the camera unit, Patent Document 1 discloses a camera body portion, a camera body, and the like. In a camera assembly structure having an optical system built in the unit, a circuit board mounted on the camera body unit and mounted with a sensor that converts optical information through the optical system into electrical information; A camera assembly structure having a first state in which the circuit board is fixed to the camera body and a second state in which the mounting position of the circuit board in the camera body can be displaced is described. Has been.

JP 2001-242521 A

  In recent years, a stereo camera using a pair of imaging units has attracted attention as a technique for measuring the three-dimensional position of a subject.

  In a stereo camera, a horizontal shift (parallax) related to an object projected on two captured images taken from a pair of imaging units is specified, and the object is detected using the principle of triangulation based on the specified parallax. The distance to the object is calculated.

  Such a stereo camera is applied to an in-vehicle system that supports safe driving of a car, a monitoring system that detects intrusion or abnormality of a suspicious person, and the like.

  In the field of automobiles, cameras, radars, etc. are installed to detect information on vehicles and obstacles ahead, and the detected information determines the risk of collision with vehicles ahead, etc. Development of technology related to ASV (Advanced Safety Vehicle) such as automatically decelerating by braking or automatically increasing / decreasing traveling speed so as to keep the distance between the vehicle and the preceding vehicle safe. It is being actively promoted.

  As a vehicle collision prevention system, a system that issues an inter-vehicle distance warning, a drowsy driving warning, a pedestrian protection, and a rear obstacle warning is considered. In addition, a system for preventing lane departure, maintaining the distance between vehicles, and automatically avoiding accidents is also considered. In such a system, a stereo-type camera is used as one of the distance measuring devices mounted to measure the distance to an object.

  This is expected to assist the driver's vision and help prevent collision accidents, and an inexpensive and highly reliable on-board stereo camera is desired.

  In an in-vehicle imaging device in which such a stereo camera or a monocular camera is mounted on a car, it is necessary to adjust the optical axis of the imaging unit with respect to the housing of the in-vehicle imaging device with high accuracy in order to attach the vehicle to the vehicle with high accuracy. .

  In a stereo camera, the optical axes of a plurality of imaging units must be parallel with high accuracy.

  As a technique for adjusting the optical axis with high accuracy, there is Patent Document 1 described above. In Patent Document 1, a circuit board on which an image pickup unit is mounted is directly fixed to a housing with screws, and a screw diameter and a hole diameter are provided so that the position of the circuit board can be adjusted, so that high-precision adjustment is achieved. Is possible.

  However, when the imaging unit is directly fixed to the casing with a screw or the like when fixing the imaging unit to the casing, there is a problem that a highly accurate positioning structure is required for the imaging unit and the casing.

  On the other hand, when the casing is manufactured by aluminum die casting or the like, high-precision processing is required to request the accuracy of the positioning structure. For this reason, there is a problem that production takes time and costs are increased.

  In view of the above problems, an object of the present invention is to provide an in-vehicle image pickup apparatus that can adjust an optical axis of an image pickup unit with respect to a housing with high accuracy while suppressing precise processing on the housing as much as possible.

In order to solve the above problems, for example, the configuration described in the claims is adopted.
The present invention includes a plurality of means for solving the above problems. To give an example, the present invention includes an imaging device having a lens and an imaging device, and a housing that holds the imaging device. And the imaging device are fixed by an adhesive layer without engaging with each other.

  According to the present invention, it is possible to reduce the cost by minimizing precise processing on the casing, and to perform highly accurate optical axis adjustment of the imaging unit with respect to the casing. Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

It is a figure which shows the vehicle carrying the stereo camera which concerns on this invention. It is the figure which showed the conceptual diagram of the stereo camera which is an example of the vehicle-mounted imaging device which concerns on this invention. It is the figure which showed an example of the camera module of the stereo camera which concerns on this invention. It is the figure which showed an example of the camera module of the stereo camera which concerns on this invention. It is the figure which showed an example of the cross section of the adhesion part of the camera module of the stereo camera which concerns on this invention, and a stay. It is the figure which showed an example of the stay of the stereo camera which concerns on this invention. It is a figure explaining the positioning structure of the stereo camera which concerns on this invention.

  Hereinafter, an embodiment of an in-vehicle imaging device of the present invention will be described in detail with reference to FIGS. 1 to 7 by taking a stereo camera as an example.

  First, an in-vehicle stereo camera, which is an application example of a stereo camera, will be described with reference to FIG.

  For example, as shown in FIG. 1, a vehicle-mounted stereo camera 20 is mounted on a vehicle 100 such as an automobile, an object within a predetermined range in front of the vehicle 100 is imaged, and an object outside the vehicle is recognized and monitored from the captured image. .

  The stereo camera 20 is disposed at a position that does not block the driver's field of view, such as near the rear mirror of the vehicle 100. The image captured by the stereo camera 20 is processed to calculate three-dimensional distance distribution information, and the road shape and the three-dimensional positions of a plurality of three-dimensional objects are detected at high speed from the calculated distance distribution information. Based on the detection result, a preceding vehicle and an obstacle are identified and a collision warning determination process is performed. If it is determined that the recognized object is an obstacle to the vehicle 100, a warning is given to the driver by displaying it on the display device 30 installed in front of the driver, and actuators (not shown) are controlled. The automatic collision avoidance control of the vehicle body is realized by connecting an external device.

  The stereo image processing used in these systems is to obtain a distance by applying a triangulation technique to a pair of captured images that are imaged at a positional interval. Generally, a pair of imaging units and a stereo image processing LSI (Large-Scale Integrated circuit) that performs triangulation processing on a pair of captured images output by these imaging units are provided.

  At this time, the stereo image processing LSI obtains the pixel position of the feature point common to each other image from the pixel information included in the pair of images and the number of pixels in which the feature point is shifted in the pair of images. Triangulation processing is realized by performing processing.

  Therefore, it is ideal that there is no deviation other than parallax between the pair of images, and it is necessary to adjust each imaging unit so that there is no deviation in optical characteristics and signal characteristics. Especially in the in-vehicle environment, for example, there is an application request to detect a vehicle ahead, a person, an obstacle, etc., and deal with it safely in advance, so it is necessary to reliably measure and recognize a distance object. .

  The importance of the relative positional relationship between the left and right imaging optical systems in a stereo camera is very high, and generally, the farther the object is, the more it is required that there is no deviation other than the above-described parallax.

  Next, an example of the form of the stereo camera of the present invention will be described with reference to FIGS. FIG. 2 shows an example of the structure of the stereo camera according to the present invention, FIGS. 3 and 4 show an example of the camera module of the stereo camera, FIG. 5 shows an example of a cross section of the bonding portion between the camera module and the stay, Shows an example of a stereo camera stay.

  As shown in FIG. 2, the stereo camera 20 according to the present embodiment includes a camera module 1A, a camera module 1B, a stay 3 that holds the camera modules 1A and 1B, a camera module 1A and 1B, and an FPC (Flexible Printed Circuits). ) A main board 4 which is a processing board mounted with an image processing LSI which is connected via 2A and 2B, is imaged by the camera modules 1A and 1B and performs stereo processing using the captured image, and the main board 4 And a cover 5 that covers the stay 3 together.

  In the stereo camera 20 of the present embodiment, the stay 3 and the camera modules 1A and 1B are fixed by the adhesive layer 13 without being engaged.

  More specifically, the stay 3 and the camera modules 1A and 1B are not fixed by a fixing jig such as a screw, but are bonded from three adhesive injection holes 3B provided in the stay 3. The optical axes of the camera module 1A and the camera module 1B are adjusted with high accuracy by the adhesive layer 13 in which the agent is cured, and the optical axes of the camera module 1A and the camera module 1B with respect to the stay 3 are highly accurate. It is fixed in an adjusted state.

  As shown in FIGS. 3 and 4, the camera modules 1 </ b> A and 1 </ b> B include a CMOS substrate 7 on which an image pickup device 7 </ b> A (see FIG. 5) such as a CMOS (Complementary Metal Oxide Semiconductor) for acquiring an image is installed, and visual information on the outside A lens holder 6 including a lens 6B that forms an image on the image sensor 7A, a lens barrel 6A for maintaining the positional relationship between the lens 6B and the image sensor 7A, and an image captured by the image sensor 7A via the FPCs 2A and 2B. And a connector 7B for outputting to the main board 4.

  As shown in FIG. 4, the lens holder 6 of the camera module 1A has two positioning pins 9A1 and 9A2, and the lens holder 6 of the camera module 1B has two positioning pins 9B1 and 9B2. The positioning pins 9A1 and 9A2 are integrally formed with the lens holder 6 of the camera module 1A, and the positioning pins 9B1 and 9B2 are integrally formed with the lens holder 6 of the camera module 1B. These positioning pins 9A1, 9A2, 9B1, and 9B2 are protrusions for adjusting the optical axes of the camera modules 1A and 1B with respect to the stay 3 by determining the relative positional relationship between the camera modules 1A and 1B with respect to the stay 3. Further, the optical axes of the camera module 1A and the camera module 1B are adjusted by determining the relative positions of the camera module 1A and the camera module 1B.

  The image sensor 7A on the CMOS substrate 7 has an optical axis, a focus, and an inclination (six axes; turn (θx · θy), height (Z), plane position (X · Y · θz) with respect to the lens 6B of the lens holder 6. )) Is adhered and fixed to the lens holder 6 in a state adjusted with high accuracy.

  The stay 3 includes stay positioning pins 8A and 8B, an insertion hole 3A into which the lens barrel 6A of the camera modules 1A and 1B is inserted, and an adhesive layer for fixing the stay 3 and the camera modules 1A and 1B without engaging them. 13 for forming the adhesive 13, the screw engagement hole 3C for fixing the cover 5 and the stay 3 with the screw 5A, and the screw for fixing the main board 4 and the stay 3 with the screw 4A. A screw engagement hole 3D and a screw engagement hole 3E for fixing the cover 5 and the main board 4 to the stay 3 with screws 5B are provided.

  The stay positioning pins 8A and 8B are protrusions formed integrally with the stay 3 provided at the side end portions of the stay 3 to determine the position of the stay 3 with respect to the camera modules 1A and 1B. The optical axes of the camera module 1A and the camera module 1B are adjusted. The stay positioning pins 8A and 8B are also protrusions that serve as a reference for mounting the stereo camera 20.

  Adhesive injection holes 3B are provided at three locations for one camera module 1A, 1B, a total of six locations, around the insertion holes 3A of the stay 3, and an adhesive layer is formed in each adhesive injection hole 3B. 13 is formed. As shown in FIG. 5, the adhesive layer 13 engages the stay 3 and the camera modules 1 </ b> A and 1 </ b> B by fixing the surface of the lens holder 6 whose plane is finished with high accuracy and the adhesive injection hole 3 </ b> B. It is fixed without depending on. The adhesive layer 13 is made of an ultraviolet curable resin.

  Next, a method for positioning the camera modules 1A and 1B and the stay 3 will be described with reference to FIG. FIG. 7 is a diagram for explaining the positioning structure of the stereo camera.

  As described above, the stay positioning pins 8 </ b> A and 8 </ b> B, which are protrusions for positioning the stay 3, are provided at the side ends of the stay 3 that is the housing. The camera module 1A has two positioning pins 9A1 and 9A2 which are positioning members integrally formed with the lens holder 6, and the camera module 1B has two positioning pins 9B1 which are positioning members integrally formed with the lens holder 6. , 9B2 are provided.

  The positioning jig 11 is used to position the stay 3 and the camera modules 1A and 1B (adjusting the optical axis) and to position the camera module 1A and the camera module 1B (adjusting the optical axis).

  As shown in FIG. 7, the positioning jig 11 is provided in positioning receiving grooves 12A and 12B provided at positions corresponding to the stay positioning pins 8A and 8B of the stay 3, respectively, and positioning pins 9A1 and 9A2 of the camera module 1A. Positioning holes 10A1 and 10A2 provided at corresponding positions and positioning holes 10B1 and 10B2 provided at positions corresponding to the positioning pins 9B1 and 9B2 of the camera module 1B, respectively. The positional relationship between the positioning holes 10A1 and 10A2 and the positioning holes 10B1 and 10B2 is adjusted with high accuracy, and the positional relationship between the positioning holes 10A1 and 10A2 and the positioning holes 10B1 and 10B2 and the positioning receiving grooves 12A and 12B is also high. Adjustments have been made.

  In positioning, first, the positioning pin 9A1 and positioning hole 10A1 of the camera module 1A are aligned, and the camera module 1A is installed on the positioning jig 11 with the positioning pin 9A2 and positioning hole 10A2 aligned. Similarly, the camera module 1B is installed on the positioning jig 11 with the positioning pins 9B1 and the positioning holes 10B1 of the camera module 1B aligned and the positioning pins 9B2 and the positioning holes 10B2 aligned. Thereafter, the stay positioning pin 8A and the positioning receiving groove 12A of the stay 3 are aligned, and the stay 3 is installed on the positioning jig 11 in a state where the stay positioning pin 8B and the positioning receiving groove 12B are aligned.

  In this state, the adhesive layer 13 is formed by injecting an ultraviolet curable adhesive into the six adhesive injection holes 3B and solidifying by applying ultraviolet irradiation.

  At this time, as described above, the positional relationship between the positioning holes 10A1, 10A2 and the positioning holes 10B1, 10B2 is adjusted with high accuracy, and the positioning holes 10A1, 10A2, the positioning holes 10B1, 10B2, and the positioning receiving groove 12A are adjusted. , 12B is also highly adjusted. For this reason, when the adhesive layer 13 is formed, the camera modules 1A and 1B are adjusted in a state where the optical axes of the camera modules 1A and 1B and the optical axes of the camera modules 1A and 1B with respect to the stay 3 are adjusted with high accuracy. It is fixed to the stay 3.

  Thereafter, the integrated camera module 1A, camera module 1B and stay 3 are removed from the positioning jig 11, FPCs 2A and 2B are attached to the camera modules 1A and 1B, and the FPCs 2A and 2B and the main board 4 are attached.

  Next, the main board 4 and the stay 3 are fixed with screws 4A, and then the cover 5 and the stay 3 are fixed with screws 5A and 5B.

  Next, the effect of this embodiment will be described.

  The above-described stereo camera 20 of the present invention includes the camera modules 1A and 1B having the lens 6B and the image sensor 7A, and the stay 3 that holds the camera modules 1A and 1B. The stay 3 and the camera modules 1A and 1B include It is fixed by the adhesive layer 13 without engaging.

  Since it is fixed by the adhesive layer 13 without having an engaging portion in this way, a positioning structure is not provided between the stay 3 and the camera modules 1A and 1B. Positioning processing can be reduced as compared with the prior art, and the low-cost stereo camera 20 can be obtained. Further, the optical axis accuracy of the camera modules 1A and 1B can be ensured.

  The camera modules 1A and 1B adjust the optical axes of the camera modules 1A and 1B with respect to the stay 3, and positioning pins 9A1, 9A2, 9B1, and 9B2 for adjusting the optical axes of the camera modules 1A and 1B. Have The stay 3 has stay positioning pins 8A and 8B. The stay positioning pins 8A and 8B and the positioning pins 9A1, 9A2, 9B1 and 9B2 adjust the optical axes of the camera module 1A and the camera module 1B with respect to the stay 3. Is. For this reason, since the optical axes of the stay 3 and the camera modules 1A and 1B are adjusted using the positioning jig 11, the stay positioning pins 8A and 8B, and the positioning pins 9A1 and 9A2, the positioning processing accuracy of the stay 3 is required. There are few places to go. Therefore, the highly accurate positioning process of the stay 3 can be reduced as compared with the prior art, and the manufacturing cost of the stereo camera 20 can be reduced.

  Furthermore, the camera modules 1A and 1B have two positioning pins 9A1, 9A2, 9B1, and 9B2, so that the optical axis is adjusted with high accuracy with a simple configuration, and the low-cost stereo camera 20 and can do.

  In addition, since the positioning members of the camera modules 1A and 1B are the positioning pins 9A1 and 9A2 and the positioning pins 9B1 and 9B2, the optical axis can be adjusted with high accuracy while being simple, and the stereo camera 20 can be manufactured at a lower cost. It can be.

  Furthermore, since the adhesive layer 13 is made of an ultraviolet curable resin, the adhesive layer 13 can be formed in a short time, so that the stereo camera 20 can be made at a lower cost.

  The stay positioning pins 8A and 8B and the positioning pins 9A1, 9A2, 9B1 and 9B2 are integrally formed, so that the stay positioning pins 8A and 8B of the stay 3 and the positioning pins 9A1 and 1B of the camera modules 1A and 1B are formed. Processing for increasing the accuracy of 9A2, 9B1, and 9B2 is unnecessary, and the stereo camera 20 can be manufactured at a lower cost.

<Others>
In addition, this invention is not restricted to said embodiment, A various deformation | transformation and application are possible. The above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to the one having all the configurations described.

  For example, the positioning pins 9A1 and 9A2 and the positioning pins 9B1 and 9B2 can be holes instead of the pins. In this case as well, the low-cost stereo camera 20 can be obtained while ensuring the optical axis accuracy of the camera modules 1A and 1B with respect to the stay 3.

  Further, the number of positioning pins 9A1, 9A2, 9B1, and 9B2 does not need to be two for one camera module 1A and 1B, and at least one is sufficient, but two or more are desirable. Further, when two or more positioning pins 9A1, 9A2, 9B1, and 9B2 are provided, the position provided does not need to be the center in the vertical direction of the camera modules 1A and 1B, and can be installed at an arbitrary position.

  Similarly, the stay positioning pins 8A and 8B need not be provided at the two ends or provided at the side end portions, and can be arbitrarily provided.

  Also, the camera modules 1A and 1B do not have to be two, and can be appropriately provided in the in-vehicle imaging device according to the application.

1A ... Camera module (imaging device, first imaging unit)
1B ... Camera module (imaging device, second imaging unit)
2A, 2B ... FPC
3 ... Stay (housing)
3A ... Insertion hole 3B ... Adhesive injection hole 3C, 3D, 3E ... Screw engagement hole 4 ... Main substrate 5 ... Cover 6 ... Lens holder 6A ... Lens barrel 6B ... Lens 7 ... Substrate 7A ... Imaging element 7B ... Connector 8A, 8B ... Stay positioning pin (casing side positioning part)
9A1, 9A2 ... Positioning pins (first positioning member, imaging device side positioning member)
9B1, 9B2 ... positioning pins (second positioning member, imaging device side positioning member)
10A1, 10A2, 10B1, 10B2 ... positioning hole 11 ... positioning jigs 12A and 12B ... positioning receiving groove 13 ... adhesive layer 20 ... stereo camera (vehicle-mounted imaging device)
30 ... Display device 100 ... Vehicle

Claims (8)

An imaging apparatus having a lens and an imaging element;
A housing for holding the imaging device,
The vehicle-mounted imaging device, wherein the housing and the imaging device are fixed by an adhesive layer without being engaged. The in-vehicle imaging device according to claim 1,
The image pickup apparatus includes a positioning member for adjusting an optical axis of the image pickup apparatus with respect to the casing. The in-vehicle imaging device according to claim 1,
The imaging apparatus includes a first imaging unit having a first positioning member and a second imaging unit having a second positioning member,
The on-vehicle imaging device, wherein the first positioning member and the second positioning member adjust optical axes of the first imaging unit and the second imaging unit. The in-vehicle imaging device according to claim 3,
The housing has a positioning member,
The positioning unit, the first positioning member, and the second positioning member adjust optical axes of the first imaging unit and the second imaging unit with respect to the casing. The in-vehicle imaging device according to claim 2,
The image pickup apparatus includes at least two positioning members. The in-vehicle imaging device according to claim 3,
The on-vehicle imaging device, wherein the first positioning member and the second positioning member are pins or holes. The in-vehicle imaging device according to claim 1,
The in-vehicle imaging device, wherein the adhesive layer is an ultraviolet curable resin. The in-vehicle imaging device according to any one of claims 2 to 6,
The vehicle-mounted imaging device, wherein the positioning member, the first positioning member, or the second positioning member are integrally formed.

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