DE112022001866T5 - IMAGING DEVICE - Google Patents

Abstract

Provided is an imaging device suitable for miniaturization, which can reduce vibrations of a circuit substrate in the imaging device and vibrations on a sensor such as an imaging element even in a structure in which fixing points and a vibration-proof member are reduced. An imaging device includes: an imaging element; a substrate that processes an image; and a housing in which the substrate is fixed by a plurality of substrate fixing parts, the substrate comprising a plurality of cantilever parts which are areas outside a polygonal area having the substrate fixing part at each vertex, and a natural frequency of the cantilever parts for each of the Boom parts are different.

Description

Technical area

The present invention relates to an imaging device that is mounted on a vehicle such as an automatic four-wheeler or a motorcycle and captures an image of the front of a host vehicle.

General state of the art

In order to realize a safe and comfortable automobile society, a driver assistance system has been increasingly installed on vehicles such as an automatic four-wheeler and a motorcycle in recent years. Among these, systems have been developed that strive for safety, convenience and comfort of a driver and a passenger, such as: B. a collision damage reduction braking device that automatically slows the speed of the vehicle before a collision with an obstacle, an automatic distance between vehicle control device that automatically follows a lane while maintaining a distance between vehicles with respect to a vehicle in front a speed at a substantially constant distance, a device for preventing lane departures and sign recognition. In such a system, an external detection device is used that detects a vehicle, a pedestrian or the like and measures a distance to an object.

In an imaging device, which is a type of external recognition device, it is important to ensure a clear field of view in order to accurately recognize the outside world. There is a possibility that driving-related vibrations of a vehicle are transmitted to an imaging device, an imaging element receives an influence from the vibrations of the vehicle and an image oscillates, resulting in unclear external detection, and a circuit substrate may receive an influence from the vibrations of the vehicle Vehicle receives, whereby repeated stress is applied to the circuit element mounted on the circuit substrate or separation occurs in the soldered portion.

PTL 1 is herein known as a conventional technique for suppressing separation due to repetitive stress applied to a circuit element of a circuit substrate in an environment of receiving driving vibrations of a vehicle. For example, the abstract of this patent describes “In an electronic device that includes an electronic substrate on which is mounted an electronic component having a plurality of terminals and a support tool that supports the electronic substrate, a separation is formed in the electronic component without installing a vibration-proof member." as a problem and discloses an electronic device "The electronic substrate 3 and the terminal block 2 are attached so that a vibration mode of the electronic substrate 3 at the time of resonance is a vibration mode capable of a “To prevent separation from occurring in the electronic component 3b.” as a solution to the problem.

List of citations

Patent literature

PTL 1: JP 2020-161547 A

Brief description of the invention

Technical problem

Specifically, as described in paragraph 0018 and the like of PTL 1, the electronic device of PTL 1 is a power conversion device that is mounted on a vehicle such as a hybrid vehicle or an electric vehicle and supplies power to a traction motor. In this power conversion device, as in 1 and 3 As illustrated in the same document, the screw 4 is often used to fix the electronic substrate 3 to the terminal block 2, and the fixing point P of the electronic substrate 3 is reinforced so that the electronic substrate 3 is in a vibration mode that can be suppressed. For this reason, the power conversion device made of PTL 1 has a structure that is unsuitable for miniaturization because the area of the mounting portion in the area of the electronic substrate increases, resulting in an increase in the size of the electronic substrate. However, in a case of an in-vehicle power conversion device where the need for miniaturization is not so strong, such an increase in the substrate area is not considered a problem.

On the other hand, it is urgent to downsize the imaging device, which is often attached to the upper portion of the inner surface of the windshield, so as not to block the driver's field of vision as much as possible, and is a direct application of the vibration mode suppression structure of PTL 1 undesirable as this leads to an increase in the size of the electronic substrate and, as a result, leads to an increase in the size of the imaging device.

Further, as a structure for suppressing the vibration of the electronic substrate without using the vibration mode suppression structure of PTL 1, there is also known a structure in which a vibration-proof element is provided on the electronic substrate, but adding the vibration-proof element to one Increase in the size of the imaging device, an increase in the number of components and a complication of the manufacturing process.

The present invention has been conceived in view of the above-mentioned problems, and it is an object of the present invention to provide an imaging device that can detect both vibrations of a circuit substrate in the imaging device and vibrations transmitted to a sensor such as an imaging element, even in one Structure in which attachment points and a vibration-proof element are reduced.

Solution to problem

The present application includes several means for solving the above-mentioned problems, one example of which is achieved by including an imaging member, a substrate for processing an image, and a housing in which the substrate is fixed by a plurality of substrate fixing parts, the substrate having a plurality of cantilever parts which is an area outside a polygonal area having the substrate fixing part at each corner point, and each of the cantilever parts has a different natural frequency.

Advantageous effects of the invention

According to the imaging device of the present invention, even with the structure in which the fixing points and the vibration-proof member are reduced, it is possible to reduce both the vibration of the circuit substrate in the imaging device and the vibration transmitted to the sensor such as the imaging member.

Accordingly, since it is possible to reduce the vibration of the optical axis of the imaging device due to the vibration of the vehicle, it is possible to provide an imaging device with high external detection accuracy and high reliability. In addition, it is possible to provide an imaging device that has a low probability of circuit element separation. Since the fixing portions and the vibration proof member can be reduced, the effective area of the circuit substrate can be increased, and as a result, it is possible to provide an imaging device that achieves miniaturization and weight reduction.

Brief description of the drawings

• [ 1 ] 1 is an external perspective view of an imaging device of a first embodiment.
• [ 2 ] 2 is a perspective view of the imaging device of the first embodiment.
• [ 3 ] 3 is a perspective view of an imaging device of a comparative example.
• [ 4 ] 4 is a vibration mode simulation diagram of a circuit substrate of the imaging device of the comparative example.
• [ 5 ] 5 is an illustrative diagram of a substrate fixing part of the imaging device of the first embodiment.
• [ 6 ] 6 is an illustrative diagram of a vibration reducing effect of the imaging device of the first embodiment.
• [ 7 ] 7 is an illustrative diagram of a substrate mounting part of an imaging device of a second embodiment.
• [ 8th ] 8th is an illustrative diagram of a substrate fixing part of an imaging device of a third embodiment.
• [ 9 ] 9 is an illustrative diagram of a substrate fixing part of an imaging device of a fourth embodiment.
• [ 10 ] 10 is an illustrative diagram of a substrate fixing part of an imaging device of a fifth embodiment.
• [ 11 ] 11 is an illustrative diagram of a substrate fixing part of an imaging device of a sixth embodiment.
• [ 12 ] 12 is a perspective view of an imaging device of a seventh embodiment.
• [ 13 ] 13 is an illustrative view of a substrate fixing part of the imaging device of the comparative example.
• [ 14 ] 14 is an illustrative view of the substrate fixing part of the imaging device of the comparative example.
• [ 15 ] 15 is an illustrative diagram of a substrate fixing part of the imaging device of the seventh embodiment.
• [ 16 ] 16 is an illustrative diagram of a substrate fixing part of an imaging device of an eighth embodiment.
• [ 17 ] 17 is an illustrative diagram of a substrate fixing part of an imaging device of a ninth embodiment.

Description of embodiments

Hereinafter, an imaging device of the present invention will be described with reference to the drawings. Note that since the configurations denoted by the same reference numerals have the same functions, redundant description will be omitted unless otherwise specified.

First embodiment

First, an imaging device 101 according to a first embodiment of the present invention will be described with reference to 1 until 6 described.

1 is an external perspective view of an imaging device 101 of the present embodiment mounted on a vehicle such as an automatic four-wheeler or a motorcycle, and 2 is a perspective view of the imaging device 101. Note that, in order to clearly describe the arrangement of the configurations in each drawing, in the present embodiment, an orthogonal coordinate system is set, which includes an x-axis, which indicates an optical axis direction (forward direction ) of the imaging device 101 as a positive direction, a y-axis having an upward direction of the imaging device 101 as a positive direction, and a z-axis having a rightward direction of the imaging device 101 as a positive direction.

The imaging device 101 is a device mounted on a vehicle in a state in which a positive direction of an x-axis coincides with a traveling direction of the vehicle and a negative direction of a y-axis coincides with a downward direction of the vehicle, and the one Detects position, a speed, and the like of an object (other vehicles, pedestrians, etc.) present in the vehicle's traveling direction based on a change in an image over time by continuously imaging the vehicle's traveling direction.

The imaging device 101, which in 1 and 2 is a monocular imaging device in which an imaging substrate 3 on which an imaging element 2 is mounted and a circuit substrate 11a on which a plurality of circuit elements 6 (61 to 65) are mounted are housed in a housing 1 made of metal (for example). For example, by die-casting aluminum), a lower surface and a rear surface are opened and fins for heat dissipation are provided on an upper surface, and a lens 4 protrudes forward from an upper portion of the housing 1. Note that it is assumed that the imaging element 2, the imaging substrate 3 and the lens 4 are integrated as an imaging module 5 using a holder (not shown). In addition, the circuit substrate 11a is provided with a plurality of substrate fixing parts 12 (12a to 12c) for fixing the circuit substrate 11a to the case 1. In the substrate fixing part 12, the circuit substrate 11a may be fixed to the case 1 using a screw, for example, or the circuit substrate 11a may be fixed to the case 1 using an adhesive. Further, case fixing parts 7 (7a to 7c) used for fixing the case 1 to the vehicle are provided on the front surface and the rear portions of the left and right surfaces of the case 1.

Here, for example, the circuit element 6 mounted on the circuit substrate 11a is as follows. The first circuit element 61 is a field programmable gate array (FPGA) that processes an image signal output from the imaging element 2, and is a circuit element that requires heat conduction to the package 1 and generates a large amount of heat.

The second circuit element 62 is a circuit element such as a memory used for temporarily storing data. The third circuit element 63 is a circuit element that performs various types of signal processing such as: B. a microprocessor unit (MPU). The fourth circuit element 64 is a large circuit element such as a capacitor. The fifth circuit element 65 is a relatively small one Circuit element, such as a power supply circuit. Note that the plurality of circuit elements 6 are not limited to these examples, and a part thereof may be omitted or another type of circuit element may be added.

After the imaging module 5 and the circuit substrate 11a are installed, the open portions on the bottom surface and the rear surface of the case 1 are closed by a cover (not shown) such as an aluminum plate with a wiring hole. Consequently, the circuit substrate 11a of the imaging device 101 and the ECU (Electronic Control Unit) of the vehicle can be electrically connected via the wiring hole of the cover, and the output of the circuit substrate 11a can be reflected in vehicle control by the ECU.

In recent years, it has become necessary to further downsize an imaging device, and in order to downsize the imaging device, it is important to downsize a built-in circuit substrate. As a measure for downsizing the circuit substrate, there is a method of reducing the number of substrate attaching parts 12 to increase a substrate area (hereinafter referred to as an effective substrate area) on which the circuit element 6 can be mounted. When the substrate fixing parts 12 are reduced, the circuit substrate 11a can be reduced in size and the effective substrate area of the circuit substrate 11a can be maintained at the same time, so that the case 1 covering the circuit substrate 11a can be reduced in size and the imaging device 101 as a whole can be reduced in size. Particularly, in the case of a monocular imaging device in which the area of the circuit substrate 11a is small, such as the imaging device 101 of the present embodiment, since the area ratio of the substrate fixing part 12 in the circuit substrate 11a is large, the reduction in downsizing of the substrate fixing part 12 is very large effectively.

A problem in a case where the number of the substrate fixing parts 12 of the circuit substrate 11a is reduced is that vibrations in a bending mode or the like are likely to occur in the cantilever part 13 of the circuit substrate 11a. In the case of the circuit substrate 11a 2 For example, since the substantially triangular cantilever parts 13R and 13L are formed outside the triangular area having the substrate fixing parts 12a to 12c as corner points, there is a possibility that the cantilever parts 13R and 13L vibrate due to vibration of the vehicle due to traveling. When the boom parts 13R and 13L vibrate, the vibration is transmitted to the imaging member 2, and a disturbance corresponding to the vibration is recorded in the continuously captured image. As a result, the measurement accuracy of the distance or speed of the object, which is the output of the imaging device 101, decreases. In recent years, with an increase in the performance of the imaging device 101, such as an increase in viewing angle, high accuracy and high-speed compatibility, the allowable amount of vibration of the imaging element 2 has been reduced, and therefore it is more necessary to reduce vibration of the imaging device 101.

Furthermore, when a load is repeatedly applied to the circuit element 6 mounted on the circuit substrate 11a due to vibrations of the cantilever parts 13R and 13L, separation may occur in the soldered portion or the like. Therefore, from the viewpoint of preventing separation, it is necessary to reduce vibrations in the cantilever parts 13R and 13L of the circuit substrate 11a.

<Circuit substrate 11X of imaging device 100X of comparative example>

At this point, the principle of generating vibration of the cantilever parts 13R and 13L in the circuit substrate 11X; which is installed in the imaging device 100X of the comparative example using the perspective view of 3 and the vibration mode simulation diagram 4 described. It should be noted that a redundant description of points that 1 and 2 are common will be omitted from the following description.

In a conventional imaging device (not shown), there are many structures in which a circuit substrate is fixed to a housing through substrate fixing members 12 provided at four corners of the circuit substrate. In contrast, in the circuit substrate 11X of the in 3 In the illustrated comparative example, the circuit substrate 11X is fixed to the case 1 using three substrate fixing parts 12a to 12c.

As described above, in the circuit substrate 11X of the comparative example, since the effective substrate area can be increased by reducing the substrate fixing parts 12 by one space compared to the conventional package, the circuit area can be increased by increasing Increase in the effective substrate area can be reduced.

Since products such as an imaging device are often designed to be bilaterally symmetrical, in this comparative example, which follows a conventional design concept, the circuit substrate 11X has an isosceles triangular region, each of which has the front substrate fixing part 12b in the middle, the rear substrate fixing part 12b at the right end and the rear substrate fixing part 12c at the left end are arranged to be bilaterally symmetrical to form an isosceles triangular region on the circuit substrate 11X. When such a circuit substrate 11X is used, as shown in the vibration mode simulation diagram 4 , the cantilever parts 13R and 13L having the same shape outside the isosceles triangular region may overlap and resonate in the vibration mode at the same frequency, and the respective vibration amplitudes may increase. Subsequently, when strong vibrations of the boom parts 13R and 13L are transmitted to the imaging member 2 and a change in imaging position corresponding to the vibrations is reflected in each image continuously captured by the imaging member 2, an error occurs in position, distance and speed of the object, which are calculated based on the continuously captured images, and thus the measurement accuracy of the imaging device deteriorates.

Furthermore, the boom parts 13R and 13L resonate, as shown in 4 shown, repeatedly exerts a heavy load on the circuit element mounted on the circuit substrate 11X, and separation may occur in the soldered portion or the like.

To solve these problems, it is generally effective to provide a vibration-proof element for preventing vibration of the circuit substrate 11X, but in this case, adding the vibration-proof element causes an increase in the size of the imaging device, an increase in the number of components, and a complication of the manufacturing process. Furthermore, in a case where the vibration-proof member is provided in the imaging device, since the front surface side is imaged and the position, speed and the like of the object are recognized from the difference in the image depending on time, Difference in the image 0.1 degrees or less with respect to the angle when the distance is detected particularly at the time of high-speed movement, and the position deviation occurs in the image in the vibration mode of the vibration-proof member, and in the calculation of the speed and the An error occurs in the position of the object. Therefore, the structure in which the vibration-proof member is provided is not desirable from this point of view either. In addition, from the viewpoint of maintaining measurement accuracy, it is very important to maintain the installation positions of the vehicle body and the sensor, and since the vehicle body and the sensor are normally fixed stably, the vibrations of the vehicle body are directly transmitted to the imaging device. Therefore, a resonance mode of a circuit substrate or the like, which is a component of the imaging device, is transmitted to the sensor through a housing or the like, and there is a possibility that a positional deviation occurs in the image and an error in speed or position occurs comes.

<Circuit substrate 11a of imaging device 101 of the present embodiment>

In order to solve the problem caused by the configuration of the comparative example as described above, in the circuit substrate 11a of the present embodiment, the substrate fixing part 12a included in FIG 4 Comparative example shown is arranged in the middle on the front side, moved slightly to the right from the middle, as in 5 shown. As a result, since the boom part 13R and the boom part 13R can be designed asymmetrically, the frequency (natural frequency f _R ) of the vibration mode of the boom part 13R and the frequency (natural frequency f _L ) of the vibration mode of the boom part 13L can be designed differently. In 5 The substrate fixing part 12a is arranged to the right, but can also be arranged to the left.

If the natural frequencies f _R and f _L of the cantilever parts 13R and 13L are designed differently from one another, as in 6 As shown, in the circuit substrate 11X of the comparative example, the heavy root state occurs in which the two vibration modes coincide, whereas in the circuit substrate 11a of the present embodiment, the heavy root state is eliminated and the vibration amplitude of the vibration mode decreases in both of the cantilever parts 13R and 13L. As a result, vibration conduction from the cantilever parts 13R and 13L to the imaging member 2 is reduced. Furthermore, in the circuit substrate 11a of the present embodiment, by providing the two substrates fixing parts 12b and 12c on the imaging member 2 side, the distance from the imaging member 2 to the cantilever parts 13R and 13L increases, and this structure also reduces the vibration conduction from the cantilever parts 13R and 13L to the imaging member 2. As described above, in of the imaging device 101 of the present embodiment, the vibration conduction from the boom parts 13R and 13L to the imaging member 2 is reduced, so that the position and speed of the object can be measured with high accuracy from the images continuously captured by the imaging member 2.

Furthermore, by suppressing vibration of the cantilever parts 13R and 13L, a repetitive stress applied to the circuit element 6 mounted on the circuit substrate 11a and separation of a soldered portion or the like around the circuit element 6 is also reduced be prevented.

Besides, since the effective substrate area of the circuit substrate 11a can be increased by reducing the substrate attaching parts 12, when the circuit elements 6 to be attached are the same, the circuit substrate 11a and the housing 1 can be reduced in size, and as a result, downsizing and weight reduction of the imaging device 101 can be realized become.

[Formel 2] $$\left|\frac{f_R-f_L}{f_{av}}\right|\ge 15\text{\%}$$

At this time, in consideration of vibration damping and the like, in order to prevent the overlap of the vibration modes of the cantilever parts 13R and 13L, the difference between the natural frequencies f _R and f _L can generally be set to about 20 to 30 Hz, but in particular the Substrate fixing part 12a can be arranged at a position in which the natural frequencies f _R and f _L satisfy the relationships from Formulas 1 and 2. Note that the position of the substrate fixing part 12a, which satisfies the relationships of Formulas 1 and 2, is influenced by the rigidity of the circuit substrate 11a, the arrangement of the circuit elements 6 on the circuit substrate 11a and the like, and therefore cannot be adjusted unconditionally. but, for example, a position offset by about 10 to 20% with respect to the width from the center of the circuit substrate 11a in the width direction, or a position offset by about 5 to 10 mm in the width direction from the center of the circuit substrate 11a is offset in the width direction.

[Formula 1] $$f_{av}=\frac{f_R+{\mathrm{<figure-callout\; id="2"\; label="f\; L"\; filenames="DE112022001866T5\_0003.png,DE112022001866T5\_0005.png"\; state="\{\{state\}\}">f</figure-callout>}}_L}{2}$$

[Formula 2] $$\left|\frac{f_R-f_L}{f_{av}}\right|\ge 15\text{\%}$$

Since the position of the center of gravity of the vehicle body is a neutral position with respect to the disturbances (vibrations) emanating from the vehicle body, when the imaging device 101 is installed at the position of the center of gravity of the vehicle body, it is important to note that the external force acting on the imaging device 101 is exercised, can be reduced and a highly reliable recognition result can be output.

Accordingly, in order to mount the imaging device 101 so that it is close to the position of the center of gravity of the vehicle body while ensuring the field of view of the imaging device 101, it is desirable to extend the imaging device 101 horizontally forward from the center of gravity of the vehicle body position. This is located near the front grille on a regular automatic four-wheeler and between the headlight and the front wheel on a regular motorcycle.

As described above, according to the imaging device of the present embodiment, even with the structure in which the fixing points and the vibration-proof member are reduced, it is possible to control both the vibration of the circuit substrate in the imaging device and that on the sensor such as the imaging member to reduce transmitted vibrations. Accordingly, since it is possible to reduce the vibration of the optical axis of the imaging device due to the vibration of the vehicle, it is possible to provide an imaging device with high external detection accuracy and high reliability. In addition, it is possible to provide an imaging device that has a low probability of circuit element separation. Further, since the fixing portions and the vibration proof member can be reduced, the effective area of the circuit substrate can be increased, and as a result, it is possible to provide an imaging device that achieves miniaturization and weight reduction.

Second embodiment

Next, an imaging device 102 according to a second embodiment of the present will be described with reference to 7 described. Note that description of points common to the first embodiment is omitted.

7 is an illustrative diagram of the substrate mounting part 12 of the imaging device 102 according to the present embodiment. In the circuit substrate 11a of the first embodiment, the position of the substrate fixing part 12a is shifted to the right (or left) by a predetermined amount to obtain the desired natural frequencies f _R and f _L satisfying formulas 1 and 2, but in the circuit substrate 11b In the present embodiment, the surfaces of the cantilever parts 13R and 13L are designed differently to obtain the desired natural frequencies f _R and f _L.

The natural frequencies f _R and f _L of the cantilever parts 13R and 13L of the circuit substrate 11b of the present embodiment are obtained by the rigidity and weight. Therefore, in the case of the circuit substrate 11b having a uniform plate thickness, as shown in 7 shown, by providing the substrate fixing parts 12a to 12c so that the areas S _R and S _L of the cantilever parts 13R and 13L are different, the natural frequencies f _R and f _L are adjusted to a desired size relationship. Specifically, the substrate fixing part 12a may be at a right position similar to that shown in FIG 5 be arranged, or, although not shown, the substrate attachment part 12a can be as in 3 may be disposed front and center, and the substrate fixing part 12b or the substrate fixing part 12c may be moved forward or toward the middle to make the surfaces S _R and S _L different.

Even with such a configuration of the present embodiment, the same effects as the first embodiment can be obtained.

Third embodiment

Next, an imaging device 103 according to a third embodiment of the present invention will be described with reference to 8th described. Note that description of points common to the first embodiment is omitted.

8th is an illustrative diagram of the substrate fixing part 12 of the imaging device 103 according to the present embodiment. In the circuit substrate 11c of the present embodiment, the moments of the cantilever parts 13R and 13L are made different to obtain desired natural frequencies f _R and f _L satisfying Formulas 1 and 2.

As in 8th As shown, when the weights of the cantilever parts 13R and 13L are m _R and m _L, respectively, and the distances to the straight lines connecting the substrate fixing parts 12 to the centers of gravity of the cantilever parts 13R and 13L are L _R and L _L , respectively, that Moment M _R of the boom part 13R is calculated by m _R × L _R , and the moment M _L of the boom part 13L is calculated by m _L × L _L. When the magnitude relationship between these moments is changed, the magnitude relationship between the natural frequencies f _R and f _L also changes, so that the natural frequencies f _R and f _L are changed by adjusting the positions of the substrate fixing parts 12 or adjusting the weights m _R and m _L of the cantilever parts 13R and 13L can be adjusted to a desired size ratio. In order to adjust the weights m _R and m _L of the boom parts 13R and 13L, a method of providing either a weight or a reinforcing plate in the boom part 13 may be adopted.

Even with such a configuration of the present embodiment, the same effects as the first embodiment can be obtained.

Fourth embodiment

Next, an imaging device 104 according to a fourth embodiment of the present invention will be described with reference to 9 described. Note that description of points common to the first embodiment is omitted.

9 is an illustrative diagram of the substrate mounting part 12 of the imaging device 104 according to the present embodiment. In the circuit substrate 11a of the first embodiment, the arrangement of the circuit elements 6 was not mentioned, but in the circuit substrate 11d of the present embodiment, with focus on the size and the like of each circuit element 6, as in 9 As shown, relatively large circuit elements 6 are arranged on the side connecting the substrate fixing parts 12a to 12c, and a relatively small circuit element 6 is arranged on the cantilever part 13.

If the large circuit elements 6 are arranged on the side that fastens the substrate connecting parts 12a to 12c of the circuit substrate 11d, the circuit substrate has high rigidity on the side connecting the substrate fixing parts 12a to 12c. Therefore, the vibration amplitude of the electrical component is reduced, and the vibration regarding the imaging element 2 can be reduced. In particular, a large fourth circuit element 64 such as a capacitor is effective in reducing vibration because a torque is likely to occur and increase the vibration amplitude of the circuit substrate 11d.

Further, if the heat conduction member connected to the housing 1 for heat dissipation of the fifth circuit element 65 (a relatively small circuit element such as a power supply circuit) in the cantilever portion 13R has a gel mold or a rubber mold and also has a heat dissipation and damping function, the vibration amplitude of the circuit substrate 11d can be reduced, and the temperature rise of the circuit element and the imaging element 2 can also be reduced. As the temperature of the circuit element 6 or the imaging element 2 increases, a noise component of the signal increases and the measurement accuracy decreases. Therefore, it is necessary to reduce the temperature of the circuit element or the imaging element 2.

Specifically, the number of pixels of the imaging element 2 increases along with an increase in the viewing angle, high accuracy and high-speed compatibility of the imaging device 104, and the amount of heat generation (power consumption) of the imaging element 2 and the circuit element 6 increases significantly, and the temperature rise of the imaging element 2 and the circuit element 6 becomes a problem.

Even with such a configuration of the present embodiment, the same effects as the first embodiment can be obtained.

Fifth embodiment

Next, an imaging device 105 according to a fifth embodiment of the present invention will be described with reference to 10 described. Note that description of points common to the first embodiment is omitted.

10 is an illustrative diagram of the substrate fixing part 12 of the imaging device 105 according to the present embodiment. A feature of the present embodiment as in 10 1, is that vibration suppression is taken into account in a case where the housing fixing parts 7a to 7c of the imaging device 105 are provided in the vicinity of the substrate fixing parts 12a to 12c.

Since the vibration mode of the housing 1 is a vibration mode in which the housing fixing parts 7a to 7c are nodes, in the present embodiment, when the housing fixing parts 7a to 7c of the imaging device 105 and the substrate fixing parts 12a to 12c are brought close to each other, the polygonal overlaps Area having the case fixing parts 7a to 7c at respective corner points, and the polygonal area having the substrate fixing parts 12a to 12c at respective corner points. By arranging the case fixing parts 7 and the substrate fixing parts 12 in this manner, the influence of the vibration mode of the housing 1 on the vibration mode of the circuit substrate 11e is suppressed, and the transmission of the vibration caused by the housing 1 to the imaging element 2 is reduced.

According to the present embodiment, in addition to the effect of the first embodiment, an effect of suppressing the influence of the vibration mode of the housing 1 can also be achieved.

Sixth embodiment

Next, an imaging device 106 according to a sixth embodiment of the present invention will be described with reference to 11 described. Note that description of points common to the first embodiment is omitted.

11 is an illustrative diagram of the substrate mounting part 12 of the imaging device 106 according to the present embodiment. In the first embodiment, the substrate fixing parts 12 are provided at three locations on the circuit substrate 11a. However, in the present embodiment, the substrate fixing parts 12a and 12b of the circuit substrate 11f are provided at two locations to further increase the effective substrate area of the circuit substrate 11f. In the case where this configuration is adopted, the substrate fixing parts 12a and 12b are provided so that the natural frequency f _R of the cantilever part 13R on the imaging element 2 side is higher than the natural frequency f _L of the other cantilever part 13L. In other words, the substrate fasteners supply parts 12a and 12b satisfying the relationship S _L > S _R are arranged so that the areas S _R and S _L of the cantilever parts 13R and 13L reduce the area S _R of the cantilever part 13R on the imaging element 2 side.

In the case 1 of the present embodiment, a projection 8 is provided for abutment on the left end of the circuit substrate 11f. The projection 8 functions as a positioning pin of the circuit substrate 11f, and not only improves the mounting accuracy of the circuit substrate 11f, but also contributes to reducing the vibration amplitude of the cantilever parts 13R and 13L, so that by the configuration of the present embodiment, the same. Effect as in the first embodiment can be achieved.

Seventh embodiment

Next, an imaging device 107 according to a seventh embodiment of the present invention will be described with reference to 12 until 15 described. Note that description of points common to the first embodiment is omitted.

12 is a perspective view of the imaging device 107 according to the present embodiment. 13 is an illustrative diagram of a substrate fixing part 12 of an imaging device 100Y of the comparative example. 14 is an illustrative diagram of a substrate fixing part 12 of an imaging device 100Z of the comparative example. 15 is an illustrative diagram of a substrate fixing part 12 of the imaging device 107 according to the present embodiment.

As in 12 As shown, the imaging device 107 of the present embodiment includes a right imaging substrate 3R on which a right imaging element 2R is mounted, a left imaging substrate 3L on which a left imaging element 2L is mounted, a circuit substrate 11g on which a plurality of circuit elements 6 are mounted, and a case 1A accommodating the right imaging substrate 3R, the left imaging substrate 3L and the circuit substrate 11g therein. A plurality of circuit elements 6 are mounted on the circuit substrate 11g.

The right imaging element 2R is mounted on the housing with a right imaging module 5R, which includes the right imaging element holder (not shown), the right imaging substrate 3R, and a right imaging element 2R to which a right lens 4R is attached, as a set 1A attached. Likewise, the left imaging element 2L is attached to the housing 1A with a right imaging module 5L including the left imaging element holder, the left imaging substrate 3L and a second imaging element 2L to which a left lens 4L is attached as a set. The imaging device 107 is enclosed by the housing 1A and the cover by attaching the cover to the housing 1A. By enclosing the case 1A with a metal such as an aluminum die casting and the cover with a metal such as an aluminum plate, dustproofness is ensured, and anti-electromagnetic field measures and heat dissipation are also improved. Electrical connection between the vehicle and the imaging device 107 is performed by connecting wiring via an opening (not shown) on the rear surface of the housing 1A to an internal electrical terminal.

Here, in the imaging device 107 (stereo camera) of the present embodiment, the front side is imaged by the right imaging module 5R and the left imaging module 5L, from the pair of image details, a feature point common to the respective images is extracted by an integrated circuit processing to obtain the number of pixels (parallax) at which the positions of the feature points between the pair of images are shifted is performed, and the distance is calculated. Accordingly, if there is a deviation other than the original parallax between the pair of images, an error occurs in the distance measurement result. In addition, with improvement of the imaging device 107 in performance such as increase in viewing angle, high accuracy and high-speed compatibility, the allowable amount of deviation is reduced, and it is necessary to reduce the deviation of the optical axis. As a factor of deviation, there is a deviation of the optical axis due to thermal deformation caused by a difference in the expansion amount of each component at the time of a temperature rise due to sunlight, heat generation inside the device, or the like.

In many conventional imaging devices, such as in 13 shown, the imaging module 5 is attached directly to the housing 1A. A circuit substrate 11Y is also attached to the case 1A with a screw or the like, and the case 1A and the circuit substrate 11Y are normally made of materials having different linear properties Have expansion coefficients. Therefore, assuming that the package 1A has a larger coefficient of linear expansion than the circuit substrate 11Y, as the temperature of the imaging device 100Y increases, the circuit substrate 11Y expands less in the left-right direction (z-axis) than that Case 1A, and the substrate fixing parts 12a to 12d such as screws are acted upon by a force from the circuit substrate 11Y toward the center with respect to the case 1A, so that the case 1A is deformed. Therefore, the optical axis of each imaging module mounted on the housing 1A is tilted. The inclination or the like of the imaging module is called an optical axis deviation, and when the optical axis deviation occurs, the measurement accuracy regarding the distance or direction of the object deteriorates. To solve such a problem, the substrate fixing parts 12a to 12d of the circuit substrate 11Y may be elastically fixed to the case 1A via rubber or the like. However, the manufacturing process becomes more complicated, such as an increase in the number of components, and the cost increases.

On the other hand, as in the in 14 Comparative example shown, when the positions of the substrate fixing parts 12a to 12d of a circuit substrate 112 are fixed to the housing 1A at positions closer to the center between the right imaging element 2R and the left imaging element 2L in a bilaterally symmetrical configuration (j in 14 is reduced), the force acting from the circuit substrate 11Z toward the center is reduced, and the deviation of the optical axis can be reduced.

However, when configuring the comparative example 14 , the cantilever parts 13R and 13L are generated outside the polygonal area having the substrate fixing parts 12a to 12d at the corner points, and the vibrations such as the bending mode are easily absorbed in the cantilever parts 13R and 13L against the disturbance such as the vibration the imaging device 100Z, and the cantilever parts 13R and 13L are caused to overlap and resemble the vibration mode on the lower side 14 to resonate. In a case where the vibration of the circuit substrate 11Z is applied to the right imaging element 2R and the left imaging element 2L, a vibration difference occurs in the image, resulting in a difference in distance and speed, leading to deterioration in measurement accuracy . In addition, by improving the imaging device 100Z in performance such as increase in viewing angle, high accuracy and high-speed compatibility, an allowable amount of deviation due to vibration becomes small, and it is necessary to reduce the vibration of the imaging device 100Z.

Further, vibration of the cantilever parts 13R and 13L may cause a repetitive stress to be applied to the circuit element mounted on the circuit substrate 11Z, resulting in separation of a soldered portion or the like. Therefore, it is necessary to reduce the vibration of the circuit substrate 11Z. Providing a vibration-proof element to prevent general vibrations leads. to an increase in the size of the device, an increase in the number of components and a complication of the manufacturing process. Furthermore, when the anti-vibration member is provided in the device, since the position and speed of the object are recognized from a difference in the images depending on time when the front surface side is imaged, the difference in the images is 0 .1 degree or less with respect to an angle when a distance is detected particularly at the time of high-speed movement, and in the vibration mode of the vibration-proof member, a positional deviation occurs in the image and an error in speed and position occurs. Therefore, it is not desirable to provide the vibration-proof member in the imaging device. From the viewpoint of measurement accuracy, it is very important to maintain the vehicle body mounting positions of the sensor, and usually the vehicle body and the sensor are stably fixed and the vibrations of the vehicle body are transmitted to the imaging device. Therefore, a resonance mode of a circuit substrate or the like, which is a component in the device, is transmitted to the sensor via a housing 1A or the like, and there is a possibility that a positional deviation occurs in the image and an error in speed or the like occurs Position comes.

In view of such a problem, in the circuit substrate 11g of the present embodiment, as shown in 15 shown, the cantilever parts 13R and 13L are provided outside the polygonal area having the substrate fixing parts 12a to 12d at the corner points, and the natural frequencies of the cantilever parts 13R and 13L are designed different from each other. Alternatively, the length d _R of the boom part 13R can be made longer than the length d _L of the boom partly 13L. Alternatively, the width w _R of the boom part 13R can be made longer than the width w _L of the boom part 13L. Alternatively, the area of the boom part 13R may be made larger than the area of the boom part 13L. Alternatively, the moments MM _R and MM _L , including the weight mm _R of the cantilever part 13R and the distances L _R and L _L to the side connecting the plurality of substrate fixing parts 12a to 12d close to each other with the centers of gravity of the cantilever parts 13R and 13L, are for each boom part 13 is designed differently.

By having the natural frequencies as in the oscillation mode on the lower side of 15 for each cantilever part 13 of the circuit substrate 11g can be designed differently by any method, as in 6 As shown in the first embodiment, the severe root state in which the two vibration modes coincide is eliminated, so that the vibration amplitude of the vibration mode is reduced and the vibrations can be reduced to the right imaging element 2R and the left imaging element 2L. Since the vibration amplitude can be reduced, the detection of the position, speed and the like of the object can be measured with high accuracy, and the imaging device 107 is extremely reliable without separation of the soldered portion or the like due to the reduction of the repetitive stress of the circuit element on which the circuit substrate 11g is attached. In addition, an additional component such as rubber for fixing the circuit substrate 11g is not required, and the imaging device 107 becomes inexpensive and highly reliable with high measurement accuracy without optical axis deviation.

Eighth embodiment

Next, an imaging device 108 according to an eighth embodiment of the present invention will be described with reference to 16 described. Note that description of points common to the seventh embodiment is omitted.

16 is an illustrative diagram of the substrate mounting part 12 of the imaging device 108 according to the present embodiment. In a circuit substrate 11h of the present embodiment, in order to make the natural frequencies of the cantilever parts 13 different from each other, the substrate fixing parts 12a and 12d at the positions of the front end and the rear end are spaced to the right from the center of the circuit substrate 11h by a distance La in the left-right direction, and the substrate fixing parts 12c and 12d are spaced at the positions of the front end and the rear end to the left of the center of the circuit substrate 11h by the distance La in the left-right direction. In 16 , the substrate fixing parts 12a and 12b on the right side are arranged side by side in the front-rear direction, and the substrate fixing parts 12c and 12d on the left side are also arranged side by side in the front-rear direction. However, the distance to the center of each substrate fixing part 12 may be designed differently, and the substrate fixing parts 12 may be arranged in a trapezoidal shape so that the distances on the left and right sides are different overall.

The configuration of the present embodiment can also provide the same effects as those of the seventh embodiment described above.

Ninth embodiment

Next, an imaging device 109 according to a ninth embodiment of the present invention will be described with reference to 17 described. Note that, in the present embodiment, a description of points common to the seventh embodiment is omitted.

17 is an illustrative diagram of the substrate fixing parts 12a to 12d of the imaging device 109 according to the present embodiment. Also in a circuit substrate 11i of the present embodiment, the substrate fixing parts 12a to 12d are arranged so that the natural frequencies of the cantilever parts 13R and 13L are different. Specifically, the substrate fixing part 12a at a front end position is spaced to the right by the distance La in the left-right direction from the center of the circuit substrate 11i, and the substrate fixing part 12c is at the front end position to the left by the distance Lb spaced from center. In addition, the substrate fixing part 12b is spaced at a rear end position to the right by the distance Lc in the left-right direction from the center of the circuit substrate 11i, and the substrate fixing part 12d is at a rear end position to the left by the distance Lc spaced from the center.

As a result, the natural frequencies of the cantilever parts 13R and 13L of the circuit substrate 11i are different from each other, so that the heavy root state in which the two vibration modes coincide, is eliminated, the oscillation amplitude of the oscillation mode is reduced and the oscillations can be reduced to the right imaging element 2R and the left imaging element 2L.

In the circuit substrate 11i of the present embodiment, a female terminal 66 for signal input/output, power supply and the like is provided on the left side of the substrate fixing part 12b on the right rear side. As a result, since the substrate fixing part 12a on the right front side and the female terminal 66 are arranged in the insertion/extraction direction of the connector (not shown), deformation of the circuit substrate 11i and the soldered portion at the time of connector insertion/extraction can be reduced. Stresses and strains can be reduced and damage such as cracks can be prevented.

It should be noted that the present invention is not limited to the above-mentioned embodiments and includes various modifications and combinations without departing from the spirit of the present invention. Furthermore, the present invention is not limited to one including all of the configurations described in the above embodiments, and includes one in which a part of the configurations is removed.

Reference symbol list

100X to 100Z

Imaging device of comparative example

101 to 109

Imaging device of the present invention

1, 1A

Housing

2

Illustration element

2R

right image element

2L

left image element

3

Imaging substrate

3R

right imaging substrate

3L

left imaging substrate

4

lens

4R

right lens

4L

left lens

5

Mapping module

5R

right imaging module

5L

left mapping module

6

Circuit element

61

first circuit element (FPGA)

62

second circuit element (memory)

63

third circuit element (MPU)

64

fourth circuit element-(capacitor)

65

fifth circuit element (power supply circuit)

66

Socket connection

7

Housing mounting part

8th

head Start

11

Circuit substrate

12

Substrate fixing part

13

Boom part

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2020161547 A [0005]

Claims (11)

Imaging device comprising: an imaging element; a substrate that processes an image; and a housing in which the substrate is fixed by a plurality of substrate fastening parts, wherein the substrate includes a plurality of cantilever portions that are regions outside of a polygonal region having each of the substrate attachment portions at each vertex, and wherein each of the cantilever portions has a different natural frequency. Imaging device according to Claim 1 , wherein, in the substrate, each of the cantilever portions has a different moment, the moment comprising a weight of the cantilever portion and a distance to a side connecting the plurality of adjacent substrate mounting portions to a center of gravity of the cantilever portion. Imaging device according to Claim 1 , wherein, in the substrate, each of the cantilever parts has a different surface. Imaging device according to Claim 1 , wherein, in the substrate, each of the cantilever parts has a different width. Imaging device according to Claim 1 , wherein, in the substrate, each of the cantilever parts has a different length. Imaging device according to Claim 1 , wherein the substrate has three substrate attachment parts and the two of the substrate attachment parts are arranged on an imaging element side. Imaging device according to Claim 1 , wherein, in the substrate, an area of the cantilever part on the imaging element side is smaller than an area of another cantilever part. Imaging device according to Claim 1 , where, in the substrate, a circuit element on a. Side is arranged that connects the plurality of substrate attachment parts. Imaging device according to Claim 1 , wherein, in the substrate, a circuit element comprising a heat conduction element is arranged in the cantilever part. Imaging device according to Claim 1 , wherein the housing includes housing fixing parts for fixing the housing to a vehicle body, and a polygonal area having each of the substrate fixing parts at each corner point and a polygonal area having each of the housing fixing parts at each corner point overlap each other. Imaging device according to Claim 1 , wherein the substrate includes a terminal on a rear side, and the terminal is disposed at a position between left and right substrate attaching parts on the rear side of the substrate, the position being close to one of the substrate attaching parts and in a front-back direction is aligned with the substrate attachment part on the front side of the substrate.

Images