JP2002079880A - Vehicle periphery visually confirming device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To easily recognize the image content of a captured image when water droplets such as raindrops adhere to an imaging device. SOLUTION: Water-repellent thin films 23L, 23R made of a water-repellent polymer material are formed on outer surfaces of light-transmitting plates 22L, 22R of transmission windows 2L, 2R of an imaging device 11A. Water droplets are accumulated in a granular form on the surfaces of the water-repellent thin films 23L and 23R, and are scattered and removed from the surfaces of the light transmitting plates 22L and 22R due to vibrations caused by running of the vehicle, wind pressure of a head wind, and the weight of the water droplets themselves. In particular, when it is desired to scatter water droplets, the light transmitting plates 22L and 22R are forcibly vibrated by the vibrator 29.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for visually recognizing a periphery of a vehicle for photographing an external view of a blind spot of a driver and displaying the captured image to a driver in a situation where visibility is poor.

[0002]

2. Description of the Related Art In order to facilitate driving at intersections where visibility is poor, a vehicle periphery visual recognition device is attached to the front end of a vehicle or the like, and the vehicle periphery visual recognition device is used to grasp the outside situation that is a blind spot of a driver. There is technology. FIG. 6 shows a configuration diagram of a conventional vehicle periphery recognition device. The apparatus 1 for visually recognizing the periphery of a vehicle is provided outside the vehicle, and captures an image of a landscape around the vehicle in two opposite directions, and a mirror image for inverting an image signal supplied from the image capture device 11. The image processing apparatus includes an inversion processing unit 12 and a display unit 15 disposed in the vehicle interior and displaying an image signal obtained from the mirror image inversion processing unit 12.

The imaging device 11 has a light-shielding case 3 provided with a pair of left and right transmission windows 2L and 2R made of transparent glass or the like on both sides thereof. The prism 4 is housed in a posture in which the apex portion 5 faces the front portion of the case 3 (the upper portion of the case 3 in FIG. 6), and the prism side surfaces 8L and 8R face the left and right transmission windows 2L and 2R, respectively. And the prism side 8
L, 8R, light rays 18 which are guided on the imaging surface via a predetermined imaging lens 9 after changing the optical path in the prism 4
An image sensor 10 for converting L and 18R into image signals is housed and arranged on the rear side of the prism 4. At this time, the optical axis 25 of the imaging lens 9 coincides with the bisecting line of the vertex angle portion 5 of the isosceles triangular section of the prism 4 behind the prism 4 (downward in FIG. 6). It is arranged to be.

The imaging device 11 is, for example, an imaging device 1
1 is attached to a front bumper or a front grill so that the front part (the front part of the case 3) faces forward of the vehicle and the transmission windows 2R and 2L face right and left, respectively.

In this state, the light rays 18 corresponding to the left scene
As shown in FIG. 6, L transmits through the transmission window 2L and the prism side surface 8L, then travels inside the prism 4, and reaches the prism side surface 8R. After being internally reflected by the prism side surface 8R, the light exits from the prism rear surface 8B, is imaged by the imaging lens 9, and is guided to the left half surface 10L of the imaging surface of the imaging device 10.

Considering this symmetrically, the light ray 18R corresponding to the right side scene is similarly guided to the right half surface 10R of the imaging surface of the imaging device 10. Then, both are converted into image signals by the image sensor 10.

[0007] The left and right scenes are imaged in this way, and the image signals thus imaged are subjected to mirror image inversion processing in the mirror image inversion processing unit 12 and supplied to the display unit 15 as a monitoring visual field image as shown in FIG. . In the display unit 15, the left view taken in from the transparent window 2L is displayed on the left half screen 15L as the left view image 19L, and the right view taken in from the transparent window 2R is displayed in the right half screen 15R as the right view image 19R. Will be displayed. Therefore, when an approaching object such as a vehicle approaches in a position with poor visibility, the driver can recognize the approaching object by visually recognizing the screen of the display unit 15.

[0008]

However, in the conventional vehicle periphery recognition device, the transmission window 2L,
If water droplets such as raindrops adhere to the 2R, the refraction or scattering of the light rays may disturb the monitoring visual field image and make it difficult to visually recognize the image content.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus for visually recognizing an area around a vehicle, which makes it easy to visually recognize the image content when water droplets such as raindrops adhere.

[0010]

Means for Solving the Problems In order to solve the above problems,
The invention according to claim 1 captures an image around the vehicle by guiding light incident from a transmission window portion of a case body installed at a predetermined position outside the vehicle to an imaging element housed in the case body. And a vehicle periphery visual recognition device that displays the image on a predetermined display unit, wherein the transmission window includes a water-repellent thin film made of a water-repellent polymer material formed on an outer surface of a light-transmitting plate. It is.

According to a second aspect of the present invention, there is provided the apparatus for visually confirming the vicinity of a vehicle according to the first aspect, further comprising a vibrator for vibrating the light transmitting plate.

According to a third aspect of the present invention, there is provided the vehicle surrounding visual recognition device according to the second aspect, wherein the control unit performs on / off control of the vibrator based on a predetermined signal given from the vehicle. It has more.

According to a fourth aspect of the present invention, there is provided the vehicle periphery visual recognition device according to the third aspect, wherein the predetermined signal includes a vehicle speed signal and / or a brake signal, and the control unit includes:
The vibration is limited only when it is determined based on the vehicle speed signal that the traveling speed of the vehicle is lower than a predetermined reference speed and / or when it is determined that the brake is activated based on the brake signal. This is for controlling the vessel to be turned on.

According to a fifth aspect of the present invention, there is provided the apparatus for visually recognizing the vicinity of a vehicle according to the fourth aspect, wherein the control unit determines that the running speed of the vehicle is constant based on the vehicle speed signal. ON control of the operation of the display unit is performed only when it is determined that the following condition is satisfied, and the constant reference speed is set to be greater than the constant threshold speed.

According to a sixth aspect of the present invention, in the vehicle periphery visual recognition apparatus according to the third aspect, the predetermined signal includes an on / off signal of a predetermined switch installed near a driver's seat. .

According to a seventh aspect of the present invention, there is provided the apparatus for visually confirming the vicinity of a vehicle according to any one of the first to sixth aspects, wherein the case body is installed at a front portion of the vehicle, and The transmission windows for capturing left and right images are formed on both sides.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic configuration diagram of a vehicle periphery visual recognition device 1A according to an embodiment of the present invention, and FIG. 2 is an example of a state in which an imaging device 11A of the vehicle periphery visual recognition device 1A is disposed in a vehicle. FIG. Elements having functions similar to those of the conventional example shown in FIG. 6 are denoted by the same reference numerals.

A device 1A for visually confirming the vicinity of a vehicle according to this embodiment.
As shown in FIGS. 1 and 2, an image pickup device 11A installed below the front bumper 17 in the vehicle 16 and an instrument in the vehicle interior for displaying images around the vehicle taken by the image pickup device 11A. LCD or CR provided at a position where the driver can easily see
A display unit 15 made of T or the like, and a mirror image inversion processing unit 12 that performs mirror image inversion processing on an image signal captured by the imaging device 11A and supplies the image signal to the display unit 15.

The imaging device 11A comprises a light-shielding case 3,
A pair of left and right transmissive windows 2L, 2R, which are made of a translucent resin such as PMMA and are respectively mounted on openings formed on both sides of the case 3 and disposed in the case 3, for example, a CCD disposed in the case 3 An imaging device 10 such as a camera, an imaging lens 9, and light rays 18L entering from the respective transmission windows 2L and 2R.
18R is converted into an optical path, and the left half surface 10L or the right half surface 10R of the imaging surface of the imaging device 10 is converted via the imaging lens 9.
And a prism 4 that guides the prism.

Transparent plates 22L and 22R made of transparent glass or the like are used as the transmissive windows 2L and 2R. The outer surfaces of the translucent plates 22L and 22R are coated with transparent silicon resin or fluorine resin. A water-repellent (hydrophobic) polymer material is coated as a water-repellent thin film 23L, 23R having a thickness of several μm or less. It is desirable that these transmission windows 2L and 2R be set so that their outer surfaces are arranged along a vertical plane.

The prism 4 is made of, for example, a glass material BK7 (refractive index n: 1.517) and is formed into a prism having a cross section of an isosceles triangle. The vertex angle 5 of this prism 4 is
For example, it is disposed toward the front of the case (in FIG. 1, above the case 3), and is fixed and held by, for example, a prism fixing member 3 </ b> A with the prism side surfaces 8 </ b> L and 8 </ b> R facing the transmission windows 2 </ b> L and 2 </ b> R of the case 3. It is arranged in the case 3. The prism fixing member 3A fixes the prism 4 by, for example, sandwiching the left and right corners of the rear portion (lower portion in the figure) of the prism 4 from the left and right sides, and also forms the rear regions of the prism side surfaces 8R and 8L (the prisms in FIG. 1). Side 8
R, 8L) also serves to block unnecessary light rays that do not constitute the left and right views incident on the lower region (R, 8L).

Further, behind the prism 4 (downward in FIG. 1), the optical axis 25 of the imaging lens 9 is set at the vertex angle 5 of the isosceles triangular section of the prism 4.
It is fixed by the lens holder 26 so as to coincide with the dividing line. Then, in the imaging device 10, behind the imaging lens 9, the imaging surfaces 10L and 10R are parallel to the rear surface 8B of the prism, and the left half surface 1 of the imaging surface.
The center 30 of the boundary between 0L and the right half surface 10R is fixed so as to be located on the optical axis 25.

The operation of the vehicle periphery recognition device having such a configuration will be described. For example, as shown in FIG. 1, the light ray 18L corresponding to the left scene is transmitted through the transmission window 2L and the prism side surface 8L.
Then, the light travels through the inside of the prism 4 and reaches the prism side surface 8R. After being internally reflected by the prism side surface 8R, the light exits from the prism rear surface 8B and is imaged by the imaging lens 9 to form the left half surface 10L of the imaging surface of the imaging device 10.
Will be guided to.

Considering this symmetrically, the light ray 18R corresponding to the right side scene is similarly guided to the right half surface 10R of the imaging surface of the imaging device 10. Then, both of them are converted into image signals by the image pickup device 10, and the monitoring visual field image is displayed on the display unit 15.

Here, as shown in FIG. 3, when the weather is raining or the like, water droplets 24 such as raindrops are applied to the light transmitting plate 2 of the transmitting windows 2L and 2R.
The water droplets 24 that adhere to the outer surfaces of the 2L and 22R or that splash from a vehicle traveling ahead due to car washing or while the vehicle is traveling may adhere to the light transmitting plates 22L and 22R. . These water droplets 24 form light transmitting plates 22L, 2L.
If the light-transmitting plates 22L, 22L remain attached to the 2R,
The light incident through R may be refracted or scattered by the water droplets 24, disturbing the monitoring visual field image displayed on the display unit 15, and making it difficult to visually recognize the image content.

However, in this embodiment, the water-repellent thin films 23L, 23L are provided on the surfaces of the light transmitting plates 22L, 22R.
23R, the water-repellent thin films 23L, 2L
The water droplets 24 are accumulated in a granular form by the 3R, and scattered (reference numeral 28) from the surfaces of the light transmitting plates 22L and 22R due to vibration caused by the vehicle traveling in the traveling direction 26, the wind pressure of the head wind 27 and the weight of the water droplets 24 themselves. Removed. Therefore, it is possible to reduce the disturbance generated in the monitoring visual field image displayed on the display unit 15.

As shown in FIG. 4, the light transmitting plates 22L and 22R are reliably vibrated to reliably remove the water droplets 24 adhered to the water repellent thin films 23L and 23R.
The vibrator 29 may be installed at the end of the L or 22R.

The vibrator 29 uses a piezoelectric vibrating element, and is attached to, for example, the inside of the rear end of the light transmitting plates 22L and 22R which is outside the field of view. An AC electric signal of, for example, about several KHz to several tens KHz is applied to the vibrator 29, and the piezoelectric vibration element is mechanically vibrated by the AC electric signal at a frequency at which a sound wave is generated. By transmitting the mechanical vibration to the light transmitting plates 22L and 22R, the light transmitting plate 2
Water droplets adhering to the surfaces of the 2L and 22R can be forcibly scattered by vibration.

Here, the mechanical vibration of the vibrator 29 may be driven at all times, but it is often particularly effective when the vehicle is stopped or running at a low speed. Only when the brake pedal is depressed, or when the driver presses a predetermined switch provided near the driver's seat such as an instrument panel, the vibrator 29 is operated to transmit the light transmitting plate 22L. , 22
R may be vibrated.

For example, if the display unit 15 is activated only when the traveling speed of the vehicle 16 decreases below a certain reference speed, the display unit 15 vibrates at a slightly earlier timing than when the display unit 15 is activated. By operating the detector 29, disturbance of the monitoring visual field image captured by the imaging device 11A and displayed on the display unit 15 can be reduced.

More specifically, as shown in FIG.
A, on / off control of the operations of the mirror image inversion processing unit 12, the display unit 15, and the vibrator 29 is performed by a predetermined control unit 31, and the control unit 31 receives a vehicle speed signal, a brake signal, and a driver's seat. A signal from a predetermined switch is input. Then, in the control unit 31, for example, when the traveling vehicle speed of the vehicle 16 is reduced to 20 Km / h or less based on the vehicle speed signal and the brake signal is ON (that is, when the brake is operating) And vibrator 2
9. The operation of the imaging device 11A and the mirror image inversion processing unit 12 is started.

In this case, the control unit 31 also performs on / off control of the display unit 15. In the on / off control of the display unit 15, the running of the vehicle 16 is performed based on the vehicle speed signal. When the vehicle speed is reduced to 10 km / h or less (threshold speed) and the brake signal is ON (that is, when the brake is operated), the display unit 15
The operation of may be started. Then, the traveling speed of the vehicle 16 is gradually reduced by the operation of the brake, and is reduced to 20 km / km.
When the vehicle speed reaches h, the operation of the vibrator 29, the imaging device 11A, and the mirror image inversion processing unit 12 is started, and thereafter, the traveling speed of the vehicle 16 is reduced to 10 Km / h (threshold speed), and the display unit 15 At the time when the light-transmitting plate 22L,
The water droplets that have adhered to 22R have already been scattered and removed by the operation of vibrator 29. Therefore, the monitoring field-of-view image without disturbance can be displayed on the display unit 15. Thereafter, the display of the monitoring visual field image on the display unit 15 may be continued until the traveling vehicle speed of the vehicle 16 exceeds 10 km / h.

In the above embodiment, the imaging device 11A
Was installed below the front bumper 17 of the vehicle 16 to image the landscape in front of the vehicle 16 in the left and right direction. It may be possible to take an image of a landscape such as a rear left-right direction. Alternatively, the left and right scenes are imaged simultaneously in the above embodiment, but the left and right scenes may be imaged independently.

In the above embodiment, the on / off control of the vibrator 29 is performed based on both the vehicle speed signal and the brake signal. However, the on / off control of the vibrator 29 is performed only by either the vehicle speed signal or the brake signal. / Off control may be performed, or the on / off control of the vibrator 29 may be performed based only on the switch at hand of the driver's seat, or the on / off control of the vibrator 29 may be performed by a combination of these. Is also good.

Alternatively, in the above embodiment, the control unit 3
1 determines the logical product of the fact that the traveling vehicle speed of the vehicle 16 has fallen below a certain reference speed based on the vehicle speed signal and that the brake has been activated based on the brake signal, and activates the vibrator 29. However, the vibrator 29 may be operated by determining the logical sum of these.

[0036]

According to the first aspect of the present invention, for example, the transmission windows for capturing the left and right images are formed on both sides of the front case body of the vehicle. In addition, since the transmission window is formed by forming a water-repellent thin film made of a water-repellent polymer material on the outer surface of the light-transmitting plate, even if water droplets such as raindrops adhere to the light-transmitting plate. , Water droplets accumulate in the form of particles on the surface of the water-repellent thin film, and due to the vibration caused by the running of the vehicle, the wind pressure of the head wind and the weight of the water droplet itself,
It is scattered and removed from the surface of the light transmitting plate. Therefore, it is possible to reduce the disturbance generated in the monitoring visual field image displayed on the display unit.

According to the second aspect of the present invention, since the vibrator for vibrating the light-transmitting plate is provided, water droplets attached to the surface of the light-transmitting plate are scattered and removed by the vibration of the vibrator. can do.

According to the third aspect of the present invention, the control device for controlling on / off of the vibrator based on a predetermined signal given from the vehicle is further provided, so that the driver can display on the display unit. Limited to the case where the user wants to carefully view the displayed image, for example, when the traveling speed of the vehicle is lower than a certain reference speed based on the vehicle speed signal, or when the brake is activated based on the brake signal, as in claim 4. Thus, the ON control of the vibrator can be performed. Alternatively, the on / off control of the vibrator can be performed in response to the driver arbitrarily turning on / off the switch near the driver's seat, for example.

According to the fifth aspect of the present invention, the display unit is provided only when the control unit determines that the running speed of the vehicle has become equal to or lower than the predetermined threshold speed based on the vehicle speed signal. The vehicle's running speed gradually decreases due to the operation of the brake and decelerates to a constant reference speed because the reference speed is set higher than a certain threshold speed. At this point, the operation of the vibrator is started, and thereafter, the traveling speed of the vehicle is reduced to a certain threshold speed, and the display unit starts operating. Then, at the time when the display unit is operated, since the water droplets attached to the light transmitting plate are already scattered and removed by the operation of the vibrator, the monitoring view image without disturbance is displayed at the beginning of the operation of the display unit. Can be displayed from

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a vehicle periphery recognition device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a state in which an imaging device constituting the device for visually recognizing around a vehicle is provided in the vehicle.

FIG. 3 is a diagram illustrating a state in which water droplets attached to a light transmitting plate are scattered.

FIG. 4 is a schematic diagram of a configuration of a vehicle periphery recognition device according to a modification.

FIG. 5 is a block diagram showing a vehicle periphery recognition device according to a modification.

FIG. 6 is a schematic configuration diagram of a conventional vehicle periphery recognition device.

FIG. 7 is a diagram showing a screen of a display unit in a conventional vehicle periphery recognition device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1A Vehicle periphery visual recognition device 2L, 2R Transmission window 3 Case 3A Prism fixing member 4 Prism 9 Imaging lens 10 Imaging element 11A Imaging device 12 Mirror image inversion processing unit 15 Display unit 16 Vehicle 17 Front bumper 22L, 22R Light transmission plate 23L, 23R Water-repellent thin film 29 Vibrator 31 Control unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B60R 21/00 626 B60R 21/00 626G G08G 1/16 G08G 1/16 D H04N 5/225 H04N 5/225 CE 7/18 7/18 J (72) Inventor Takayuki Tomita 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi F-term in Harness Research Institute, Inc. (reference) 5C022 AA04 AC51 AC63 AC74 AC78 AC78 5C054 AA01 CD01 CE02 CF05 HA30 5H180 AA01 CC04 CC07 CC09 EE13 LL01 LL02 LL08 LL15

Claims (7)

[Claims] 1. An image of the periphery of a vehicle is captured by guiding light incident from a transmission window of a case body installed at a predetermined position outside the vehicle to an image pickup device housed in the case body. A vehicle-periphery visual recognition device that displays a water-repellent thin film made of a water-repellent polymer material on an outer surface of a light-transmitting plate. 2. The vehicle periphery visual recognition device according to claim 1, further comprising a vibrator for vibrating the light transmitting plate. 3. The vehicle periphery visual recognition device according to claim 2, further comprising a control unit that performs on / off control of the vibrator based on a predetermined signal given from the vehicle. 4. The vehicle surrounding visual recognition device according to claim 3, wherein the predetermined signal includes a vehicle speed signal and / or a brake signal, and the control unit drives the vehicle based on the vehicle speed signal. A vehicle-peripheral visual recognition device that performs ON control of the vibrator only when it is determined that the vehicle speed has fallen below a certain reference speed and / or when it is determined that a brake has been actuated based on the brake signal. . 5. The vehicle periphery visual recognition device according to claim 4, wherein the control unit determines, based on the vehicle speed signal, that the traveling speed of the vehicle has become equal to or lower than a predetermined threshold speed. ON control of the operation of the display unit is performed only when the predetermined speed is set, and the fixed reference speed is set to be larger than the fixed threshold speed. 6. The vehicle periphery visual recognition device according to claim 3, wherein the predetermined signal includes an on / off signal of a predetermined switch installed near a driver's seat. 7. The device for visually recognizing a periphery of a vehicle according to claim 1, wherein the case body is installed at a front part of the vehicle, and left and right images are taken into both side parts of the case body. Around the vehicle, wherein the transparent windows are formed respectively.