JP2023094239A - Image display device, imaging device, and image processing device - Google Patents

Abstract

To provide an image display device capable of preventing a pickup image displayed on a display from making a passenger feel uncomfortable.SOLUTION: An electronic mirror system 10 including a wiper unit 18, and an auto light unit 24 detects from the pickup image of the camera 32 whether or not there is an environmental condition in which water droplets adhering to the rear glass affects the brightness of the photographed image of the camera 32. When determining that the environmental condition has occurred when water droplets adhering to the rear glass affect the brightness of the image captured by the camera 32, a brightness adjustment unit 40 performs a series of dimming processing to suppress brightness on the pickup image displayed on the inner mirror 28. This prevents the displayed image on the inner mirror 28 from giving a driver discomfort such as glare and flickering.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image display device, an imaging device, and an image processing device.

The imaging system of Patent Document 1 is provided with an adjustment mechanism that reduces changes in brightness of a captured image output from an imaging element of a camera device. Further, in the imaging system, the camera device is provided with a zoom function, and in the imaging system, when the zoom position is on the optical side of the threshold value, the adjustment mechanism is stopped while the wiper is in operation, so that the camera device It is possible to prevent the image picked up by the image from being uncomfortable.

The image display device of Patent Literature 2 displays an image of the rear of the vehicle captured by a camera on a display. In this image display device, the illuminance in front of the vehicle and the illuminance in the rear of the vehicle are detected, and when the illuminance in front is less than a set value and the illuminance in the rear is greater than or equal to the set value, the luminance of the display is set to the first luminance, and the illuminance in the front is is greater than or equal to the set value and the backlight luminance is less than the set value, the luminance of the display is set to a second luminance lower than the first luminance.

Patent No. 5404250 Patent No. 6763324

By the way, raindrops and water films adhering to the windshield cause scattering of light. For this reason, when an image shot through the window glass is displayed on the display, if the window glass is illuminated by the light from the headlights of other vehicles, the raindrops and water film will become brighter and the occupants will not be able to see the display. cause glare. Some cameras and the like are provided with an automatic dimming function, and glare can be suppressed by adjusting luminance with the automatic dimming function.

However, for example, when the wiper device is in operation, repeated crossing of the wiper (wiper blade) across the photographing area causes repetition of changes in brightness such as flickering in the displayed image on the display. Such a change in brightness (blinking) of the display causes discomfort such as restlessness to the passengers who view the display.

In addition, the brightness adjustment by the automatic dimming function generally requires a certain amount of response time, and cannot respond to sudden flickering such as when the wiper passes through the photographing area. Patent Document 1 has been devised in view of such a problem, but blinking due to the operation of the wiper device is caused not only by the wiper itself blocking the imaging area, but also by the windshield. There is an effect of light scattering due to raindrops and water films adhering to the surface. In particular, the water film spreads over a wide area of the glass surface due to the effect of wiping the glass surface with the wiper, which greatly affects the scattering of light. be. For this reason, scattering of light occurs only after passing through the wiper, and is quickly eliminated, thereby further promoting flickering.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned facts, and provides an image display device, an image pickup device, and an image processing device capable of obtaining a photographed image that does not cause discomfort to passengers when displayed on a display. With the goal.

An image display device according to claim 1 for achieving the above object comprises display means for displaying a display image corresponding to a photographed image of one side outside a vehicle taken through a window glass by an image pickup means, and water droplets on the window glass. an environment detection means for detecting an environmental condition capable of estimating whether or not water droplets adhere to the windshield and an environmental condition capable of estimating whether or not water droplets adhering to the windshield affect the brightness of the image captured by the imaging means; when it is estimated that the environmental state detected by the environment detection means is that water droplets adhere to the windshield, and that the water droplets adhered to the windshield affect the brightness of the displayed image; Compared to the case where it is not estimated that water droplets adhere to the windshield in the environmental state detected by the environment detection means or that the water droplets adhered to the windshield affect the brightness of the displayed image. adjusting means for adjusting the display image so as to suppress the brightness of the display image.

In the image display device of claim 1, a display image is displayed on the display means according to a photographed image obtained by photographing one side of the outside of the vehicle through the window glass by the image pickup means. The environment detection means detects an environmental state from which it can be estimated whether or not water droplets adhere to the windshield, and an environmental state from which it can be estimated whether or not the water droplets adhered to the windshield affect the brightness of the image captured by the imaging device. To detect. Further, the adjustment means adjusts the brightness of the display image when displayed on the display means.

Here, when the environmental condition is estimated to be water droplets on the windshield and the water droplets on the windshield are estimated to affect the brightness of the displayed image, the adjustment means adjusts the environmental condition to the windshield. The brightness of the display image is suppressed as compared with the case where it is not estimated that water droplets adhere to the windshield or the water droplets adhering to the windshield are not estimated to affect the brightness of the display image.

As a result, even if the windshield on which raindrops are attached is illuminated with the light from the headlights of other vehicles in a dark environment, the brightness of the display image displayed on the display means can be suppressed. The display image of the display means is too bright and the glare is not felt.

The image display device according to claim 2 is the image display device according to claim 1, wherein the environment detection means includes light/darkness detection means for detecting brightness outside the vehicle, and is operated to wipe off water droplets adhering to the windshield. A wiper device is included, and the adjustment means suppresses the brightness of the display image when the brightness outside the vehicle is below a predetermined brightness and the wiper device is operated.

In the image display apparatus of claim 2, the environment detection means includes light/darkness detection means for detecting the brightness outside the vehicle, and a wiper device that is activated when it rains to wipe off water droplets adhering to the windshield.

The adjustment means suppresses the brightness of the display image when the brightness outside the vehicle detected by the light/darkness detection means is equal to or less than a predetermined brightness and the wiper device is being operated.

As a result, it can be estimated that water droplets adhere to the windshield, and that the water droplets adhered to the windshield affect the brightness of the image captured by the imaging means. Also, the display image on the display means is too bright and the user does not feel glare.

3. The image display apparatus according to claim 1 or 2, wherein the adjustment means suppresses the brightness of the display image when displaying the display image on the display means. restrain

In the image display device according to claim 3, when the display image is displayed on the display means, the adjustment means suppresses the brightness of the display image by suppressing the luminance of the display image. To suppress luminance, for example, color correction (tone correction), gamma correction, or the like can be applied. As a result, even if the photographed image is too bright, the displayed image on the display means does not feel dazzling.

According to a fourth aspect of the present invention, there is provided an image display apparatus according to any one of the first to third aspects, wherein the adjustment means suppresses the brightness of the display image by suppressing the brightness of the display means.

In the image display apparatus according to claim 4, the brightness of the displayed image is suppressed by the adjusting means suppressing the brightness of the display means. For the suppression of the brightness of the display means, for example, suppression of the brightness of the backlight for an LCD or the like can be applied. As a result, even if the photographed image becomes too bright, the displayed image on the display means does not feel dazzling.

According to a fifth aspect of the present invention, there is provided an image display apparatus according to the first or second aspect, wherein the adjustment means suppresses the brightness of the displayed image by reducing the brightness of the image displayed on the display means.

In the image display apparatus according to claim 5, the brightness of the displayed image is suppressed by reducing the brightness of the image displayed on the display means by the adjusting means. As a result, the brightness of the display image on the display means is suppressed (becomes dark), so that even if the photographed image is too bright, the display image on the display means does not feel dazzling.

The imaging device according to claim 6 comprises imaging means for imaging one side outside the vehicle through the windshield, an environmental condition capable of estimating whether or not water droplets adhere to the windshield, and water droplets adhering to the windshield. environment detecting means for detecting an environmental condition capable of estimating whether or not it affects the brightness of an image captured by the imaging means; and when it is estimated that the water droplets adhering to the windshield affect the brightness of the image captured by the imaging means, the environmental state detected by the environment detection means is determined to be water droplets adhering to the windshield. adjusting means for adjusting the brightness of the photographed image so as to suppress the brightness of the photographed image compared to the case where it is not estimated that the water droplets attached to the windshield affect the brightness of the photographed image; including.

In the imaging device according to claim 6, when it is estimated that the environmental condition is water droplets adhering to the windshield and it is estimated that the water droplets adhering to the windshield affect the brightness of the captured image, the environmental condition is the windshield. The brightness of the photographed image is suppressed as compared with the case where it is not estimated that the water droplets adhere to the glass or the water droplets adhered to the window glass do not affect the brightness of the photographed image.

As a result, when shooting through a windshield with raindrops in a dark environment, even if the light from the vehicle's headlights illuminates the image, it is possible to prevent the image from becoming too bright. Even when an image is displayed on the display means, glare is not felt.

The image processing apparatus according to claim 7 determines an environmental condition that can be used to estimate whether or not water droplets adhere to the windshield, and whether or not the water droplets adhere to the windshield affect the brightness of the image captured by the imaging means. environment detection means for detecting an estimated environmental condition; and an image pickup means for capturing an image of one side outside the vehicle through the window glass. When it is estimated that the water droplets are attached to the windshield and that the water droplets attached to the windshield affect the brightness of the photographed image, the environmental state detected by the environment detection means is that the water droplets are attached to the windshield. an adjustment means for adjusting the brightness of the photographed image to suppress the brightness of the photographed image compared to the case where it is not estimated that the water droplets attached to the windshield affect the brightness of the photographed image; ,including.

In the image processing apparatus according to claim 7, even if the headlights of a vehicle are projected onto the windshield on which it is estimated that water droplets are attached and the attached water droplets affect the brightness of the photographed image, the windshield Since it is possible to suppress the dazzling of the photographed image picked up through the lens, even if the photographed image is displayed on the display means, the user does not feel the dazzle.

As described above, according to the present invention, since the image displayed on the display means does not cause glare, it is possible to obtain the effect that the image displayed on the display means does not cause discomfort. be done.

1 is a schematic configuration diagram of an electronic mirror system according to a first embodiment; FIG. 1 is a plan view showing a schematic configuration of a vehicle according to a first embodiment; FIG. It is a front view which shows an example of an inner mirror. It is a flowchart which shows the outline of the dimming process setting which concerns on 1st Embodiment. (A) to (C) are respectively front views of the inner mirror displaying a nighttime image, (A) showing a state in which an image subjected to light reduction processing is displayed during rain, and (B) showing a non-light-reducing image. A state in which an image is displayed when it is raining is shown, and (C) shows a state in which an image which is not subjected to light reduction processing is displayed when it is raining. FIG. 4 is a diagram showing an outline of conversion characteristics of luminance values of an output image with respect to luminance values of an input image applied to luminance adjustment in the first embodiment; FIG. 7 is a diagram showing an example of color tone characteristics applied to luminance adjustment in place of FIG. 6; (A) is a schematic configuration diagram of an electronic mirror system according to a second embodiment, and (B) is a diagram showing an example of gamma characteristics for a display according to the second embodiment. FIG. 11 is a schematic configuration diagram of an electronic mirror system according to a third embodiment; FIG. 12 is a flow chart showing an outline of main parts of dimming processing setting according to the third embodiment; FIG. It is a schematic block diagram of the electronic mirror system which concerns on 4th Embodiment. It is a flow chart showing an outline of dimming processing setting concerning a 4th embodiment. It is a schematic block diagram of the electronic mirror system which concerns on 5th Embodiment. FIG. 16 is a flow chart showing an outline of dimming processing setting according to the fifth embodiment; FIG. FIG. 11 is a schematic configuration diagram of an electronic mirror system according to a sixth embodiment; FIG. 11 is a schematic configuration diagram of an imaging device according to a seventh embodiment; FIG. 11 is a plan view showing a schematic configuration of a vehicle according to a seventh embodiment; FIG. 22 is a flow chart showing an outline of dimming processing setting according to the seventh embodiment; FIG. FIG. 11 is a schematic configuration diagram of an imaging device according to an eighth embodiment; FIG. 22 is a flow chart showing an outline of dimming processing setting according to the eighth embodiment; FIG. FIG. 4 is a diagram showing an outline of changes in brightness of a photographed image when the wiper device is not in operation and when it is in operation;

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 shows a schematic configuration diagram of an electronic mirror system 10 according to the first embodiment, and FIG. 2 shows a plan view of a schematic configuration of a vehicle 12 according to the first embodiment. In the drawings, the front side of the vehicle is indicated by an arrow FR, the right side in the vehicle width direction is indicated by an arrow HR, and the upward direction is indicated by an arrow UP.

As shown in FIG. 2, the vehicle 12 is provided with a front windshield (front glass) 16F on the vehicle front side of the vehicle compartment 14, and a rear windshield glass (rear glass) 16F as a windshield on the vehicle rear side of the vehicle compartment 14. ) 16R is installed. In addition, in the passenger compartment 14, there are a driver's seat 14D, a passenger's seat 14P on the left side of the driver's seat 14D in the vehicle width direction, and a row of rear seats 14R behind the driver's seat 14D and the passenger's seat 14P. are placed. As such a vehicle 12, a station wagon, a minivan, an SUV (Sport Utility Vehicle), or a 1-box car or a 2-box car can be applied. Also, the vehicle 12 is not limited to this, and various types of automobiles such as a 3-box car (so-called sedan type) can be applied.

The vehicle 12 includes a wiper device 18 as a wiper device and a rear wiper device 20 . The wiper device 18 is installed on the windshield 16F, and when a wiper switch (not shown) is turned on, the wiper 18A (wiper blade) is operated to wipe the outer surface (vehicle front surface) of the windshield 16F. As a result, raindrops and the like adhering to the windshield 16F are removed.

The rear wiper device 20 is installed to the rear glass 16R, and when a rear wiper switch (not shown) is turned on, the wiper 20A (wiper blade) is operated to wipe the outer surface (vehicle front surface) of the rear glass 16R. to remove raindrops, etc.

The vehicle 12 may include an automatic light device 24 that turns on/off the headlights 22 . The automatic light device 24 detects the brightness (darkness) around the vehicle 12 using an illuminance sensor (not shown) or the like, and adjusts the brightness (darkness) around the vehicle 12 to a predetermined brightness (darkness that is set when the headlights 22 are turned on). ), the headlights 22 and the like (car width lights, taillights, etc., not shown) are turned on.

As shown in FIGS. 1 and 2, the electronic mirror system 10 includes an imaging device 26, an inner mirror 28 as display means, and a display controller (display controller) for displaying an image captured by the imaging device 26 on the inner mirror 28. ECU) 30. In the first embodiment, the inner mirror 28 and the display controller 30 function as an image display device, and the display controller 30 functions as an image processing device.

The imaging device 26 includes a camera (camera device) 32 as imaging means, and the camera 32 uses an imaging element (image sensor) such as a CCD image sensor or a CMOS image sensor. The camera 32 is installed in the vehicle interior 14 on the rear side of the vehicle (on the vehicle interior 14 side of the rear glass 16R) and on the upper portion (ceiling surface side) of the central portion in the vehicle width direction. The vehicle rear as a side is imaged.

As shown in FIG. 2, the inner mirror 28 is installed in the vehicle interior 14 on the front side of the vehicle (inside the vehicle interior 14 of the windshield 16F) and in the upper part of the center in the vehicle width direction. The face faces the rear of the vehicle. As a result, the inner mirror 28 allows the driver to visually recognize the display image without obstructing the driver's field of vision in front of the vehicle when seated in the driver's seat 14D. FIG. 3 shows a schematic front view of the inner mirror 28 as seen from the rear of the vehicle.

As shown in FIG. 3, the inner mirror 28 is provided with a display (monitor) 34 that constitutes display means. (not shown). An image (video) corresponding to the image data is displayed on the inner mirror 28 by inputting an electric signal corresponding to the image data to the display 34 . The inner mirror 28 is provided with a semi-transparent half mirror that can function as a mirror on the surface side (rear side of the vehicle) of the display 34. non-display state or backlight off state), and the half mirror functions as an optical mirror.

As shown in FIG. 1, the display controller 30 is formed with an image processing section 36 and an environment detection section 38, and the image processing section 36 is formed with a brightness adjustment section 40 as adjustment means. An imaging device 26 and an inner mirror 28 (display 34) are connected to the display controller 30, and the display controller 30 performs image processing on an image (image data) captured by the imaging device 26 (camera 32). Predetermined image processing is performed in the unit 36, and the image is output to the inner mirror 28 (display 34).

Such a display controller 30 includes a microcomputer in which a CPU, a ROM, a RAM, a storage as a nonvolatile memory, an input/output interface, etc. are mutually connected via a bus so as to enable data communication. are connected (not shown). In the display controller 30, the CPU reads a program for image processing and environment detection stored in the ROM and storage, and executes the program while developing it in the RAM. Each of the 40 functions is implemented.

The image processing unit 36 performs required image processing on the image data (video data) of the captured image captured by the camera 32 to display an image corresponding to the captured image on the inner mirror 28 (display 34). . Required image processing in the image processing unit 36 includes viewpoint conversion for matching the photographed image with the viewpoint of the driver, processing for horizontally reversing the photographed image, and the like.

The luminance adjustment unit 40 adjusts the luminance of the captured image so that the brightness (luminance) of the image displayed on the display 34 falls within a predetermined range. In the brightness adjustment section 40, the brightness adjustment processing can be switched between normal processing and dimming processing in which the brightness (brightness) is suppressed (dimmed) compared to the normal processing. In the electronic mirror system 10, normal processing is performed in the brightness adjustment unit 40, so that when an image captured by the camera 32 is displayed on the inner mirror 28 (display 34), the brightness when the rear of the vehicle is too bright is suppressed. , the darkness is suppressed (brightened) when the area behind the vehicle is too dark.

In addition, the brightness adjustment unit 40 switches between normal processing and dimming processing according to the detection result (determination result) of the environment detection unit 38 .

Environment detection means is connected to the environment detection unit 38, and the environment detection means detects whether or not water droplets adhere to the rear glass 16R, and whether or not the water droplets adhered to the rear glass 16R correspond to the brightness of the image captured by the camera 32. Detect environmental conditions to infer whether they affect or not. The environment detection means includes light/darkness detection means for estimating the brightness (light/darkness or day/night) around the vehicle 12, and weather detection means (rainfall detection means) for estimating rainfall as the weather condition around the vehicle 12. ) applies.

The environment detection unit 38 determines (estimates) whether or not the brightness around the vehicle 12 has become equal to or less than a preset brightness based on the detection result of the light/darkness detection means. As the brightness detection means, an illuminance sensor (a sunshine sensor may be used) for detecting the brightness outside the vehicle can be used. is connected to the environment detector 38 .

In addition, the brightness of the captured image of the rear of the vehicle captured by the camera 32 of the imaging device 26 changes according to the brightness of the surroundings, and the captured image becomes darker as the surroundings become darker. From here, in the first embodiment, in addition to the auto light device 24 , the imaging device 26 (captured image) is used as the brightness detection means, and the imaging device 26 is connected to the environment detection section 38 .

Since the brightness (brightness) around the vehicle 12 can be obtained from calendar information indicating the sunrise and sunset at the travel location, etc., the brightness detection means includes location information of the vehicle 12 and calendar information corresponding to the location information. can be applied.

The weather detection means detects whether the surrounding weather is rainy (may include snow and fog). A raindrop sensor can be applied as the weather detection means, and in the first embodiment, the wiper device 18 that is operated by the driver in rainy weather can be applied as the weather detection means. In the first embodiment, the wiper device 18 and the rear wiper device 20 are connected to the environment detector 38 . Incidentally, when the rear wiper device 20 is not provided, only the wiper device 18 may be provided.

The environment detection unit 38 is connected to a brightness adjustment unit 40, and the brightness adjustment unit 40 performs normal processing when the environment detection unit 38 determines that the brightness around the vehicle 12 is below a predetermined level and that rain has been detected. to dimming process. In the first embodiment, the environment detection unit 38 sets normal processing or dimming processing based on the detection result of the environment detecting means, and the brightness adjustment unit 40 performs normal processing or dimming processing based on this setting. do.

Next, operation of the first embodiment will be described.
The electronic mirror system 10 is activated and starts operating when an ignition switch (not shown) of the vehicle 12 is turned on, and stops operating when the ignition switch is turned off. When the electronic mirror system 10 is operated, the imaging device 26 images the rear of the vehicle through the rear glass 16R with the camera 32, and an image corresponding to the captured image is displayed on the inner mirror 28 arranged on the front side of the vehicle in the driver's seat 14D. . As a result, the electronic mirror system 10 enables the driver to visually recognize the rear of the vehicle.

On the other hand, if the rear glass 16R is coated with raindrops or a water film formed by wiping the raindrops, the water film or the like adhered to the rear glass 16R is reflected (displayed) in the inner mirror 28 . In addition, the water film or the like adhering to the rear glass 16R tends to diffusely reflect the irradiated light. Therefore, for example, when the surroundings are dark and it is raining at night, the image displayed on the inner mirror 28 becomes too bright because the rear glass 16R receives light from the headlights of the vehicle behind. As a result, the driver who views the inner mirror 28 feels dazzled, and the driver's visibility of the rear of the vehicle is reduced (causes dazzle).

From here, in the electronic mirror system 10, luminance adjustment processing for anti-dazzle (dazzle suppression) is executed. FIG. 4 is a flowchart showing an outline of luminance adjustment (setting for luminance adjustment) processing for preventing glare.

The flowchart of FIG. 4 is executed at predetermined time intervals in the display controller 30 when the electronic mirror system 10 is activated, and ends when the electronic mirror system 10 is stopped. When the electronic mirror system 10 is activated, the display controller 30 is set so that the luminance adjustment section 40 performs normal processing (normal luminance processing).

As shown in FIG. 4, the display controller 30 performs brightness detection using the image captured by the camera 32 in the first step 200, and determines in step 202 whether the brightness of the captured image is equal to or less than a predetermined threshold value. confirm. In step 204, the display controller 30 performs brightness detection using the operation of the automatic light device 24, and in step 206, confirms whether the automatic light device 24 is operating.

The display controller 30 is set with a threshold value for determining the brightness (luminance value) detected from the image captured by the camera 32 . detect the brightness of As the brightness (luminance value) of the captured image for determining the brightness around the vehicle 12, the brightness (average value of brightness) of the periphery of the captured image can be applied. Also, as the threshold value for the captured image, a brightness (luminance value) that may cause the headlights of vehicles running in the vicinity to turn on can be applied.

The display controller 30 makes a negative determination in step 202 because the brightness (luminance value) detected from the image captured by the camera 32 exceeds the threshold value, and furthermore, because the automatic light device 24 is not operating. If a negative determination is made in step 206 , the process proceeds to step 208 . That is, when the display controller 30 determines that the brightness around the vehicle 12 exceeds the threshold value in both the captured image of the camera 32 and the auto light device 24, the process proceeds to step 208. FIG.

In step 208, the display controller 30 sets so that normal processing is performed as processing for brightness adjustment of the captured image. As a result, the photographed image of the rear of the vehicle photographed by the camera 32 is displayed on the inner mirror 28 after normal brightness processing.

When the display controller 30 detects in at least one of the captured image of the camera 32 and the auto light device 24 that the brightness around the vehicle 12 is below a predetermined level, the display controller 30 makes an affirmative determination in step 202 or step 206, and step 210. transition to

At step 210 , the display controller 30 performs rain detection using the wiper device 18 . The display controller 30 acquires the operation of the wiper device 18 at step 210 and checks to see if the wiper device 18 is operating at step 212 . At this time, if the wiper device 18 is turned off (not operated), the display controller 30 makes a negative determination in step 212 and proceeds to step 208 . As a result, even if the display controller 30 determines that the surroundings of the vehicle 12 are dark, if rain is not detected, brightness adjustment is performed by normal processing.

On the other hand, when the driver operates the wiper switch (not shown) to operate the wiper device 18 in order to remove the raindrops adhering to the windshield 16F when it is determined that the surroundings are dark, the display The controller 30 makes an affirmative determination in step 212 and proceeds to step 214 .

In step 214, the display controller 30 sets so that light reduction processing is performed as processing for brightness adjustment of the captured image. That is, the display controller 30 determines (estimates) that the ambient brightness is below the threshold value, or that the ambient is dark due to the operation of the automatic light device 24, and that it is raining. , set to perform dimming processing as luminance adjustment. As a result, an image corresponding to the image of the rear of the vehicle captured by the camera 32 is dimmed and displayed on the inner mirror 28 .

When the display controller 30 is set to perform light reduction processing for brightness adjustment, in step 216 light and shade detection is performed using the image captured by the camera 32, and in step 218 whether or not the brightness of the captured image exceeds a threshold value is determined. confirm. In step 220, the display controller 30 performs brightness detection using the auto light device 24, and in step 222, checks whether the surroundings are bright (whether the operation of the auto light device 24 has been stopped). Further, the display controller 30 performs rain detection using the wiper device 18 at step 224, and confirms whether the rain has stopped (whether the wiper device 18 has been stopped at step 226).

As a result, in the display controller 30, when the brightness (luminance value) of the captured image is equal to or less than the threshold value (negative determination in step 218), when the auto light device 24 is in operation (negative determination in step 222), Alternatively, if the wiper device 18 is operating (negative determination in step 226), the dimming process is continued.

Therefore, even if the headlights of the vehicle behind are turned on, the image displayed on the inner mirror 28 does not make the occupant feel dazzled. In addition, while the surroundings are dark and the wiper device 18 is operating, the brightness of the display image on the inner mirror 28 is kept suppressed, so that the occupant does not feel the flickering of the display image. .

Further, if the brightness (luminance value) of the photographed image exceeds the threshold value, the operation of the auto light device 24 is stopped, and the wiper device 18 is stopped, the display controller 30 executes steps 218, 222, and 222. 226 each makes an affirmative decision and proceeds to step 208 . As a result, the luminance adjustment in the luminance adjustment unit 40 is returned from the dimming process to the normal process.

6(A) to 6(C) are schematic front views of the inner mirror 28 displaying an image corresponding to the image captured by the camera 32 at night, and FIG. An outline of the conversion characteristics to be used is shown in diagrams, and FIG. The inner mirror 28 is shown displaying an image during rainfall (an image whose brightness is normally processed), and FIG. It is In FIG. 6, the horizontal axis represents the brightness (luminance value) of the input image, and the vertical axis represents the output (luminance level of the output). , the solid line indicates the conversion characteristic applied to the suppression process.

As shown in FIG. 6, the conversion characteristic applied to the dimming process is shifted so that the luminance value is lower than the conversion characteristic applied to the normal process. As a result, the image displayed on the inner mirror 28 when the dimming process is applied (see FIG. 5A) is compared to when the normal process is applied (see FIG. 5B). Overall brightness is suppressed.

On the other hand, when it is raining, raindrops adhere to the rear glass 16R, and the rear wiper device 20 is operated to form a water film or the like. As shown in FIG. 5C, when the headlights of the vehicle behind the rear glass 16R are irradiated with water droplets or a water film at night, the water droplets or the like diffusely reflect the light from the headlights. In particular, when the rear wiper device 20 is operated and a water film is formed on the rear glass 16R, the water film becomes bright and not only makes the driver feel dazzled, but also reduces the visibility of the displayed image. visibility behind the vehicle) is also reduced.

Here, the electronic mirror system 10 is set to perform dimming processing when the surroundings of the vehicle 12 are dark and it can be determined that it is raining, and luminance is adjusted so that the luminance value of the displayed image is lowered. I do. Therefore, as shown in FIG. 5A, the brightness of the image displayed on the inner mirror 28 is suppressed. As a result, the driver is not dazzled and the visibility behind the vehicle is not lowered.

As described above, the electronic mirror system 10 uses the photographed image of the camera 32 and the auto light device 24 to detect light and darkness, and the wiper device 18 to detect rainfall. This makes it possible to reliably estimate whether there is a possibility that the image displayed on the inner mirror 28 will be dazzling. Moreover, since the function of the vehicle 12 is used to determine (estimate) whether or not the image displayed on the inner mirror 28 is likely to be dazzling, it is possible to prevent the image displayed on the inner mirror 28 from being dazzling. There is no need to add functional components for

In the electronic mirror system 10, the brightness (luminance value) of the photographed image is applied when the brightness is detected using the photographed image of the camera 32. However, the contrast of the photographed image may be applied. good.

When the brightness (luminance value) of the photographed image exceeds the threshold, the operation of the automatic light device 24 is stopped, and the wiper device 18 is stopped (steps 218, 222, 226), the dimming process was switched to the normal process. However, the switching from the dimming process to the normal process may be performed when the light from the headlights of the vehicle behind does not make the driver feel dazzled. For example, regardless of the brightness of the surroundings, the operation of the wiper device 18 is stopped for a predetermined time from a state in which it can be determined that the rain has stopped (a time in which it can be determined that the influence of water droplets on the rear glass 16R has disappeared. For example, , a preset time of about several minutes to ten and several minutes), the normal processing may be switched to. Also, when the surroundings become bright enough to turn off the headlights, regardless of whether it is raining or not (regardless of whether the wiper device 18 is in operation or not), the process may be switched to normal processing.

Also, in the brightness adjustment unit 40, The conversion characteristics shown in FIG. 6 were used for luminance adjustment. However, for luminance adjustment, tone characteristics may be applied, or gamma characteristics (gamma coefficients) may be applied in place of the tone characteristics. Brightness adjustment may be performed for luminance adjustment. FIG. 7 schematically shows an example of a tone characteristic (tone curve) applied to luminance adjustment. In FIG. 7, the horizontal axis represents the brightness (luminance value) of the input image, and the vertical axis represents the output brightness (output luminance level).

As shown in FIG. 7, when the color tone characteristic is applied to the luminance adjustment, the color tone characteristic (indicated by the solid line in FIG. 7) applied to the light reduction process is normally It is set to be darker than the tone characteristics (indicated by the dashed line in FIG. 7) applied to the process. Also, when gamma (gamma correction) is applied to luminance adjustment, the gamma coefficient γ is set smaller in light reduction processing than in normal processing. Furthermore, when the brightness adjustment is applied, the captured image is adjusted so that the brightness in the dimming process is lower than the brightness in the normal process.

Therefore, by performing the dimming process, black is emphasized in the image behind the vehicle displayed on the inner mirror 28, and the overall brightness is suppressed (substantially dimmed). As a result, even if the light from the headlights of the vehicle behind the vehicle is irradiated onto the water droplets or water film attached to the rear glass 16R, it is possible to prevent the water droplets or the water film from becoming too bright. Even if it is visually recognized, it does not make you feel dazzling.

[Second embodiment]
Next, a second embodiment of the invention will be described. In the second embodiment, functional parts similar to those in the first embodiment are denoted by the same reference numerals as in the first embodiment, and detailed description thereof is omitted.

FIG. 8A shows an electronic mirror system 50 according to the second embodiment in a schematic configuration diagram. Further, in the second embodiment, the brightness is adjusted by varying the gamma correction for the image displayed on the display 34. FIG. An example of is shown in the diagram. In FIG. 8B, the horizontal axis represents the brightness level of the input image, and the vertical axis represents the brightness level of the output image. In FIG. 8B, the dashed line indicates the gamma characteristic applied to normal processing, and the solid line indicates the gamma characteristic applied to dimming processing.

As shown in FIG. 8A, in the electronic mirror system 50, a display controller 52 is formed with a brightness adjustment section 54 as adjustment means. Each of the electronic mirror system 50, the display controller 52, and the image processing section 56 of the second embodiment differs from the electronic mirror system 10 of the first embodiment in that the brightness adjustment section 54 is formed instead of the brightness adjustment section 40. It differs from the display controller 30 and the image processing unit 36 .

The image processing unit 56 executes required image processing for displaying the captured image on the inner mirror 28 (display 34) on the image data of the captured image captured by the camera 32 . The processing executed by the image processing unit 56 includes viewpoint conversion for matching the captured image with the driver's viewpoint, and processing such as left-right reversal of the captured image.

The brightness adjustment unit 54 uses a gamma characteristic preset for the display 34 to perform gamma correction as brightness adjustment (brightness adjustment) for an image (image data) output from the image processing unit 56 to the display 34. , the brightness of the image displayed on the display 34 is adjusted.

As shown in FIG. 8B, in the brightness adjustment section 54, gamma characteristics (gamma coefficients) differ between normal processing and dimming processing. In the dimming process, the gamma coefficient is set so that the output brightness is lower than the input brightness compared to the normal process. is reduced compared to the gamma factor that applies to . As a result, the luminance adjustment unit 54 applies different gamma coefficients between normal processing and dimming processing.

As shown in FIG. 8A, the brightness adjustment unit 54 receives the detection result of the environment detection unit 38 (setting of brightness processing according to the determination result). The brightness adjustment unit 54 switches between normal processing and dimming processing based on the detection result (setting of brightness processing) input from the environment detection unit 38 .

In the display controller 52 of the electronic mirror system 50 configured in this manner, normal processing is set based on the detection result of the environment detection unit 38, so that the brightness adjustment unit 54 performs normal processing based on the gamma characteristics set for normal processing. , adjusts the brightness of the image output from the image processing unit 56 to the display 34 . Further, the display controller 52 confirms that the ambient brightness of the vehicle 12 is below a predetermined level based on the photographed image of the camera 32 and the operating state of the automatic light device 24, and that it is raining based on the operating state of the wiper device 18. is detected, the dimming process is set (see FIG. 4 of the first embodiment).

When the dimming process is set, the brightness adjustment unit 54 adjusts the brightness of the image (image data) output from the image processing unit 56 to the display 34 based on the gamma characteristics set for the dimming process. . Therefore, the luminance of the image behind the vehicle displayed on the inner mirror 28 is suppressed and the brightness is suppressed. As a result, even if the headlights of the rear vehicle are turned on with water droplets or a film of water adhering to the rear glass 16R at night or the like, it is possible to prevent the water droplets or the film of water from becoming too bright.

Therefore, in the electronic mirror system 50, similarly to the electronic mirror system 10, the rearward image displayed on the inner mirror 28 during rain at night or the like does not make the driver feel dazzled, and visibility to the rear of the vehicle is reduced. I won't let you.

On the other hand, in the electronic mirror system 50 , the brightness of the image displayed on the inner mirror 28 is adjusted by performing different specific gamma correction in the brightness adjustment section 54 . Adjustment of the brightness of the image displayed on the inner mirror 28 is not limited to this, and the brightness (luminance) of a backlight (not shown) provided on the display 34 may be adjusted. In this case, in the dimming process, the brightness of the backlight may be suppressed (the amount of light is reduced) compared to the normal process. As a result, even if the light from the headlights of the vehicle behind irradiates the water droplets or water film adhered to the rear glass 16R, it is possible to prevent the water droplets or water film from becoming too bright.

[Third embodiment]
Next, a third embodiment of the invention will be described. In the third embodiment, functional components similar to those in either the first or second embodiment are given the same reference numerals as the corresponding functional components in the first or second embodiment, and detailed descriptions thereof are given. Description is omitted.

FIG. 9 shows a schematic configuration diagram of an electronic mirror system 60 according to the third embodiment.
As shown in FIG. 9 , the electronic mirror system 60 includes an imaging device 26 , an inner mirror 28 and a display controller 62 . The display controller 62 includes an image processing section 66 in which a brightness adjustment section 64 is formed, an adjustment switching section 68 as switching means, and an environment detection section 70 . In the electronic mirror system 60 according to the third embodiment, the environment detection section 70 of the display controller 62 has the same function as the environment detection section 38 of the first embodiment. The brightness adjustment unit 64 formed in the image processing unit 66 of the display controller 62 performs normal processing and dimming processing. It is different from the brightness adjustment section 40 of the first embodiment in that the Further, the display controller 62 is formed with an adjustment switching section 68. In the display controller 62, a luminance adjustment section 64 is formed instead of the luminance adjustment section 40, and the adjustment switching section 68 is formed. is different from the display controller 30 of the first embodiment.

The luminance adjustment section 64 performs luminance adjustment in the same manner as the luminance adjustment section 40 of the first embodiment. In addition, the luminance adjustment unit 64 performs normal processing in the luminance adjustment processing, first dimming processing for suppressing (dimming) the luminance (brightness) more than the normal processing, and luminance (brightness) higher than the first dimming processing. A second dimming process for further suppressing (dimming) the brightness is set. The luminance adjustment unit 64 switches between normal processing, first dimming processing, and second dimming processing according to the detection result of the environment detection unit 70 .

A rear wiper device 20 for wiping raindrops off the rear glass 16R is connected to the adjustment switching unit 68 . The rear wiper device 20 applied to the third embodiment can select a continuous mode in which the wiper 20A is operated continuously and an intermittent mode in which the wiper 20A is intermittently operated at predetermined time intervals. Continuous mode and intermittent mode are selected by operating a rear wiper switch (not shown).

When it is detected that the surroundings of the vehicle 12 are at or below a predetermined level of brightness and it is estimated that it is raining, the environment detection unit 70 performs normal processing and dimming processing. When the environment detection unit 70 is set to perform dimming processing, the adjustment switching unit 68 sets to perform dimming processing according to the operation of the rear wiper device 20 .

The average wiping speed (moving speed) of the wiper 20A (moving time per unit time) differs between the continuous mode and the intermittent mode in the rear wiper device 20, and the average wiping speed is faster in the continuous mode than in the intermittent mode. . Water droplets or the like adhering to the rear glass 16R are wiped off by the wiper 20A and spread over the rear glass 16R to form a water film or the like, but the formed water film gradually narrows. In this case, the continuous mode is often selected when the amount of rainfall is large, and even if the wiper 20A wipes frequently, the water film tends to remain, and the remaining water film causes glare in the display image of the inner mirror 28. - 特許庁

From here, the adjustment switching unit 68 sets the brightness adjustment unit 64 to perform the second dimming process when the rear wiper device 20 is operated in the continuous mode, and when the rear wiper device 20 is operated in the intermittent mode, The brightness adjustment unit 64 is set to perform the first dimming process.

Next, dimming processing executed by the display controller 62 as an operation of the third embodiment will be described.
In the electronic mirror system 60, the flowchart of FIG. 4 is executed similarly to the display controller 30 of the first embodiment. As a result, the display controller 62 switches from normal processing to dimming processing when it is determined that the surrounding brightness of the vehicle 12 is below the predetermined brightness and that rainfall is detected. When rainfall is no longer detected, the dimming process is switched to the normal process.

Here, when the display controller 62 is set to the dimming process, the dimming process is executed according to the operation of the rear wiper device 20 and the strength of the dimming process is switched. FIG. 10 is a flow chart showing an outline of the dimming process setting process executed when the display controller 62 in the electronic mirror system 60 proceeds to step 214 in FIG.

The flowchart of FIG. 10 is executed at predetermined time intervals when the display controller 62 sets the environment detection unit 70 to perform dimming processing (moving to step 214 in FIG. 4). Motion is detected and in step 232 it is determined whether the rear wiper device 20 has been activated. At this time, if the rear wiper device 20 is not operated, a negative determination is made in step 232, and the process proceeds to step 216 in FIG. As a result, the luminance adjustment unit 64 performs normal processing on the captured image. When the flowchart of FIG. 4 is applied to the third embodiment, if a negative determination is made in any of steps 218, 222, and 226, the process returns to step 214.

On the other hand, when the rear wiper device 20 is operated, the display controller 62 makes an affirmative determination in step 232 and proceeds to step 234 to confirm whether the rear wiper device 20 is operating in the intermittent mode. At this time, if the rear wiper device 20 is operated in the intermittent mode, the display controller 62 makes an affirmative determination in step 234, proceeds to step 236, and sets the first dimming process as the dimming process. As a result, the brightness adjustment unit 64 performs the first dimming process on the captured image, and an image with reduced brightness compared to the normal process is displayed on the inner mirror 28 .

If the rear wiper device 20 is operated in the continuous mode, the display controller 62 makes a negative determination in step 234, proceeds to step 238, and sets the second dimming process as the dimming process. As a result, the brightness adjustment unit 64 performs the second dimming process, in which the brightness is suppressed more than in the first dimming process, on the captured image, and the image whose brightness is further suppressed compared to the normal process is displayed as the inner image. displayed on the mirror 28.

Further, the display controller 62 confirms whether or not the rear wiper device 20 has been stopped at step 240 . Thereby, the first dimming process or the second dimming process is continued.

On the other hand, when the rear wiper device 20 is stopped, the display controller 62 makes an affirmative determination in step 240 and proceeds to step 242 . In step 242, the display controller 62 sets normal processing and terminates the light reduction processing setting processing. note that. In the display controller 62, when the normal processing is set in step 242, a predetermined period of time (for example, a period of several tens of seconds to several minutes, during which the change in the display image of the inner mirror 28 does not bother the driver) is set. Set to normal processing after the time has elapsed. As a result, in the electronic mirror system 60, even if the rear wiper device 20 is repeatedly operated/stopped or the operating time is short, the brightness of the image displayed on the inner mirror 28 is prevented from flickering. This prevents the driver from feeling uncomfortable.

In addition, in 3rd Embodiment, the dimming process was set to two steps. However, the dimming process may be set in three stages. In this case, a third dimming process is provided between the normal process and the first dimming process to dim the light more weakly than the first dimming process. is negative), the third dimming process may be set.

Further, in the third embodiment, the degree of dimming of the photographed image (the image displayed on the inner mirror 28) is varied depending on whether the rear wiper device 20 is in the intermittent mode or the continuous mode. However, the wiping speed (average wiping speed, wiping frequency) of the wiper 20A may be detected from the image captured by the camera 32, and the higher the wiping speed, the stronger the dimming may be performed according to the detected wiping speed.

At this time, the wiper (wiper blade) 20A can be detected from the captured image by extracting the shadow of the wiper 20A appearing in the captured image. The wiping speed of the wiper 20A is obtained by extracting the position of the wiper 20A from each frame of the captured image or from frames at predetermined time intervals, and calculating the average value of the amount of movement per unit time from the extracted position change of the wiper 20A. can be calculated.

In the light reduction process, a light reduction ratio is set as an index indicating the strength of light reduction with respect to the wiping speed of the wiper 20A so that the higher the wiping speed is, the higher the light reduction ratio is. The dimming process may be performed at a lower level.

[Fourth embodiment]
Next, a fourth embodiment of the invention will be described. In the fourth embodiment, functional components similar to those in any one of the first to third embodiments are given the same reference numerals as the corresponding functional components in any one of the first to third embodiments. Detailed description is omitted.

FIG. 11 shows a schematic configuration diagram of an electronic mirror system 80 according to the fourth embodiment.
As shown in FIG. 11 , the electronic mirror system 80 includes an imaging device 26 , an inner mirror 28 and a display controller 82 . The display controller 82 includes an image processing section 66 , an adjustment switching section 84 as switching means, and an environment detection section 38 . In the electronic mirror system 80 according to the fourth embodiment, an adjustment switching section 84 and an environment detection section 38 are formed in the display controller 82 instead of the adjustment switching section 68 and the environment detection section 70 of the display controller 62 of the third embodiment. is different from the electronic mirror system 60 of the third embodiment.

An image captured by the imaging device 26 is input to the adjustment switching unit 84 . The adjustment switching unit 84 detects brightness from the captured image, and sets whether or not to perform light reduction processing according to the detected brightness, and the intensity of light reduction processing when performing light reduction processing. The brightness adjustment unit 64 switches between the normal processing and the dimming processing based on the setting of the adjustment switching unit 84, and switches the strength of the dimming processing when performing the dimming processing.

Next, dimming processing executed by the display controller 82 will be described as a fourth embodiment.
FIG. 12 is a flow chart showing an outline of luminance adjustment processing executed by the display controller 82 at predetermined time intervals when the electronic mirror system 80 is activated.

As shown in FIG. 12, the display controller 82 determines that the brightness of the surroundings of the vehicle 12 is below a predetermined brightness in one of the captured image of the camera 32 and the auto light device 24, and the wiper device 18 is activated. When the rain condition is detected at step 250 , the process proceeds to step 250 .

The display controller 82 acquires the photographed image of the camera 32 in step 250, and confirms in the next step 252 whether or not the brightness of the acquired photographed image is equal to or higher than the preset brightness. As the preset brightness, it is possible to apply the brightness of the photographed image in the state where the headlights of the rear vehicle are turned on in a state where it is not raining at night or the like (the state where raindrops are not attached to the rear glass 16R). Further, as the preset brightness, brightness that makes the driver who sees the display image of the inner mirror 28 feel dazzling even when it is raining at night may be applied.

If the brightness of the photographed image does not exceed the brightness set in advance, it can be determined that the driver does not feel dazzled when viewing the image displayed on the inner mirror 28. Therefore, the display controller 82 makes a negative determination in step 252. Then go to step 208 .

Here, if the headlights of the vehicle behind are turned on in a rainy state such as at night, water droplets or the like adhering to the rear glass 16R brighten the photographed image. Accordingly, when the brightness of the captured image exceeds the preset brightness, the display controller 82 makes an affirmative determination in step 252, proceeds to step 214, and sets the dimming process.

After that, the display controller 82 detects the brightness of the captured image in step 250 . Accordingly, when the brightness of the photographed image becomes equal to or less than the preset brightness, the display controller 82 makes an affirmative determination in step 252, proceeds to step 208, and sets the brightness processing to normal processing.

In this manner, the electronic mirror system 80 (display controller 82) performs dimming processing when the brightness of the image captured by the camera 32 becomes bright enough to make the driver feel dazzled even during rain at night or the like. . As a result, for example, when there is no vehicle behind with its headlights on, which causes glare, the dimming process is not performed, and the image displayed on the inner mirror 28 feels dark due to the dimming process. You can prevent this from happening.

Further, the electronic mirror system 80 (display controller 82) prevents the driver from feeling dazzled by the display image of the inner mirror 28 due to the illumination behind the vehicle 12, not just the vehicle behind the vehicle. Therefore, it is possible to improve the driver's visibility to the rear of the vehicle.
The intensity of the dimming process set in step 242 may be set according to the brightness detected from the captured image so that the brighter the detected brightness, the stronger the dimming process.

[Fifth embodiment]
Next, a fifth embodiment of the present invention will be described. In the fifth embodiment, functional components similar to those in any one of the first to fourth embodiments are given the same reference numerals as the corresponding functional components in any one of the first to fourth embodiments. detailed description is omitted.

In the fourth embodiment, when the brightness detected from the image captured by the camera 32 becomes equal to or higher than the preset brightness, the normal processing is switched to the dimming processing. On the other hand, in the fifth embodiment, the vehicle behind is detected, and when the vehicle behind is detected, the photographed image (the image displayed on the inner mirror 28) is subjected to light reduction processing.

FIG. 13 shows a schematic configuration diagram of an electronic mirror system 90 according to the fifth embodiment.
As shown in FIG. 13 , an electronic mirror system 90 according to the fifth embodiment includes an imaging device 26 , an inner mirror 28 and a display controller 92 . The display controller 92 includes an image processing section 66, an adjustment switching section 94 as switching means, and an environment detection section 38. FIG. The electronic mirror system 90 according to the fifth embodiment differs from the electronic mirror system 80 according to the fourth embodiment in that an adjustment switching section 94 is formed in the display controller 92 instead of the adjustment switching section 84 of the fourth embodiment. do.

A vehicle detection device 96 for detecting a rear vehicle is connected to the adjustment switching section 94, and the adjustment switching section 94 switches the luminance adjustment processing of the luminance adjustment section 64 depending on whether or not a rear vehicle is detected.

Various configurations can be applied to the vehicle detection means applied to the vehicle detection device 96 as long as they can detect the vehicle behind. For example, as the vehicle detection means, a millimeter wave radar system that uses radio waves with a frequency of 30 GHz to 300 GHz called millimeter waves and can measure the position and distance of an object can be applied. In addition, the vehicle detection means includes a LiDAR (Light Detection Ranging) method that uses light such as infrared light (laser light) to measure the irradiation direction of the light and the time until the light reflected by the object is received. can be applied.

In addition, since the rear vehicle is reflected in the photographed image of the camera 32, the camera 32 (the photographed image of the camera 32) can be applied to the vehicle detection means. It is possible to perform image recognition processing such as

Furthermore, when the surroundings are dark at night and the headlights of the vehicles behind the vehicle 12 are turned on, the brightness differs between the front and the rear of the vehicle 12. Therefore, the vehicle detection means is equipped with a camera 32 and an image in front of the vehicle 12. It is also possible to use imaging means (front imaging means) for the purpose. In this case, the brightness of the captured image of the camera 32 and the captured image of the front imaging means (average brightness, brightness between preset areas such as the central portion of the captured image, etc.) is compared, and the rearward Whether or not there is a difference in brightness that can be estimated to indicate the presence of a vehicle can be applied.

The adjustment switching unit 94 detects a vehicle behind by the vehicle detection device 96, and sets (switches) the brightness adjustment unit 64 to perform dimming processing when the vehicle behind is detected. At this time, the adjustment switching unit 94 may change the strength of the dimming process in accordance with the presence or absence of a vehicle behind in a rainy state in which the surroundings are dark.

Next, a dimming process executed by the display controller 92 as an action of the fifth embodiment will be described. FIG. 14 is a flow chart showing an outline of the dimming process setting process executed by the display controller 92 at predetermined time intervals when the electronic mirror system 90 is activated.

As shown in FIG. 14, the display controller 92 determines that the brightness of the surroundings of the vehicle 12 is below a predetermined brightness in both the captured image of the camera 32 and the automatic light device 24, and the wiper device 18 is activated. If it is determined that it is raining (affirmative determination at step 212 ), the process proceeds to step 260 .

At step 260, the display controller 92 checks to see if the vehicle detection device 96 has detected a rear vehicle. At this time, if the vehicle detection device 96 has not detected a rear vehicle, the display controller 92 makes a negative determination in step 262 and proceeds to step 208 .

On the other hand, when the vehicle detection device 96 detects a rear vehicle, the display controller 92 makes an affirmative determination in step 262 and proceeds to step 264 . In step 264, the display controller 92 sets the processing in the luminance adjustment section 64 to dimming processing. As a result, even if the rear glass 16R is illuminated by the headlights of the vehicle behind, the driver can view the rear of the vehicle without feeling that the image displayed on the inner mirror 28 is dazzling to the driver.

Further, when the vehicle detection device 96 no longer detects the rear vehicle while the luminance adjustment is set to the dimming process, the display controller 92 makes a negative determination in step 262 and proceeds to step 208 . As a result, brightness adjustment is set to normal processing. Note that even if the vehicle detection device 96 detects a vehicle behind (a state in which an affirmative determination is made in step 252), the display controller 92 makes an affirmative determination in each of steps 218, 222, and 226 so that step 208 (Return to normal processing).

In this manner, the electronic mirror system 90 (display controller 92) performs normal processing if no rear vehicle is detected even during rain at night or the like. As a result, for example, when there is no vehicle behind with its headlights on, which causes glare, the dimming process is not performed, and the image displayed on the inner mirror 28 feels dark due to the dimming process. You can prevent this from happening.

[Sixth embodiment]
Next, a sixth embodiment of the present invention will be described. In the sixth embodiment, functional components similar to those in any one of the first to fifth embodiments will be given the same reference numerals as the corresponding functional components in any one of the first to fifth embodiments, and will be described in detail. omitted.

FIG. 15 shows a schematic configuration diagram of an electronic mirror system 100 according to the fourth embodiment.
As shown in FIG. 15, the electronic mirror system 100 includes an inner mirror 28, a display controller 102 for displaying an image on the inner mirror 28, and an imaging device 104 for imaging the rear of the vehicle through the rear glass 16R. The imaging device 104 in the sixth embodiment functions as the imaging device of the present invention. In the electronic mirror system 100 of the sixth embodiment, the imaging device 104 is provided with a function of adjusting the brightness of the image displayed on the inner mirror 28 (display 34). It differs from the mirror systems 10,50,60,80,90.

An image processing unit 106 is formed in the display controller 102 of the electronic mirror system 100, and the image processing unit 106 converts the captured image (image data) input from the imaging device 104 into the inner mirror 28 ( It performs the required image processing for display on the display 34).

The imaging device 104 includes a camera 32 and an imaging controller (imaging ECU) 108 as an image processing device for controlling imaging using the camera 32 and outputting a captured image. The imaging controller 108 is formed with a brightness adjustment section 40 as environment detection means and adjustment means.

The imaging controller 108 includes a microcomputer in which a CPU, a ROM, a RAM, a storage as a non-volatile memory, an input/output interface, etc. are connected to each other via a bus so as to enable data communication, and functional circuits required for the input/output interface. are connected (not shown). In the imaging controller 108, the CPU reads a required program stored in the ROM and storage and executes it while developing it in the RAM, thereby performing functions for imaging using the camera 32, functions for adjusting brightness, and functions for photographing. A function for outputting an image is realized. Thus, the imaging controller 108 is formed with an environment detection section 38 and a luminance adjustment section 40 .

In the electronic mirror system 100 configured as described above, the imaging controller 108 executes the same processing as the display controller 30 of the first embodiment for dimming processing. When the wiper device 18 is operated in a state where the brightness (luminance value) detected from the captured image by the camera 32 is equal to or less than a threshold value and the automatic light device 24 is operating, the imaging controller 108 starts shooting. Performs dimming on the image.

When the brightness detected from the image captured by the camera 32 exceeds the threshold, the operation of the automatic light device 24 is stopped (the headlights 22 are turned off), and the wiper device 18 is stopped. , the brightness adjustment for the photographed image is set to normal processing.

As a result, it is possible to prevent the headlights of the rear vehicle from dazzling the display image of the inner mirror 28 at night when it is raining. Rear visibility can be improved.

In addition, in the imaging device 104, when the environmental state is estimated to be nighttime when the imaging controller 108 is raining, the image captured by the camera 32 is subjected to light reduction processing. As a result, the imaging device 104 can output a captured image that does not make the driver feel dazzled even when displayed on the inner mirror 28 .

Such an imaging device 104 can be used not only in the electronic mirror system 100 but also in a drive recorder or the like that records a captured image in a recording medium such as a non-volatile storage. To obtain a high-quality photographed image without causing halation or the like even when the image is reproduced at night when it is raining.

Note that in the sixth embodiment, the imaging device 104 is provided with the adjustment function of the display controller 30 . However, the imaging device does not have the adjustment function of the display controller 52 according to the second embodiment, the adjustment function of the display controller 62 according to the third embodiment, the adjustment function of the display controller 82 according to the fourth embodiment, or the fifth embodiment. A display controller 92 according to the form may be provided.

Also, with the camera 32 or the like, the brightness of the captured image can be changed by adjusting the aperture (adjusting the light receiving time of the imaging element). Therefore, in the imaging apparatus, the aperture is used for light reduction processing, and when light reduction processing is performed, the aperture is adjusted so that the brightness of the captured image is lower than in the case of normal processing. good too.

[Seventh embodiment]
A seventh embodiment of the present invention will now be described. In the seventh embodiment, functional components similar to those in any one of the first to sixth embodiments are given the same reference numerals as the corresponding functional components in any one of the first to sixth embodiments, and a detailed description thereof will be given. omitted.

FIG. 16 shows a schematic configuration diagram of an imaging device 110 according to the seventh embodiment, and FIG. 17 shows a plan view of a schematic configuration of a vehicle 12A according to the seventh embodiment.

As shown in FIG. 16, the imaging device 110 includes a camera 32 as imaging means and an imaging controller 112 that controls imaging using the camera 32 and outputs a captured image. As shown in FIG. 17, in the seventh embodiment, a vehicle 12A is applied instead of the vehicle 12 according to the first embodiment, and the basic configuration of the vehicle 12A is the same as that of the vehicle 12. As shown in FIG.

In the vehicle 12A, a camera 32 is arranged in the vehicle interior 14 on the front side of the vehicle (inside the vehicle interior 14 of the windshield 16F) and at the upper part of the central portion in the vehicle width direction. The camera 32 is directed forward of the vehicle, and the camera 32 captures an image of the front of the vehicle through the windshield 16F.

Such an imaging device 110 can be used, for example, as a recording device such as a drive recorder that records a captured image in front of a vehicle, or as a display image to be displayed on a monitor (display) provided on an instrument panel. .

The imaging controller 112 is formed with a brightness adjustment section 114 as brightness adjustment means, an environment detection section 38, and an adjustment switching section . The imaging controller 112 includes a microcomputer in which a CPU, a ROM, a RAM, a storage as a non-volatile memory, an input/output interface, etc., are connected to each other via a bus so as to enable data communication. are connected (not shown). In the imaging controller 112, the CPU reads a required program stored in the ROM and the storage and executes it while developing it in the RAM. , the environment detection unit 38, the luminance adjustment unit 114, and the adjustment switching unit 116 are realized. At this time, the imaging controller 112 implements, as a function of the brightness adjustment unit 114, a function similar to that of the brightness adjustment unit 64 that switches the dimming process in a plurality of stages, for example.

The environment detection unit 38 estimates whether or not the environmental condition can be regarded as nighttime based on the image captured by the camera 32 and the operation of the automatic light device 24, and whether or not the environmental condition can be regarded as raining based on the operation of the wiper device 18. to estimate Further, the environment detection unit 38 sets brightness adjustment to normal processing or dimming processing according to the estimated environmental state.

The wiper device 18 can select an intermittent mode or a continuous mode by operating a wiper switch (not shown). It is possible.

The wiper device 18 is connected to the adjustment switching unit 116, and the adjustment switching unit 116 applies the wiping speed as the operating state of the wiper device 18, and switches the strength of the dimming process according to the wiping speed.

The switching adjustment unit 116 is set with a light reduction ratio for performing light reduction processing according to the wiping speed of the wiper device 18 (reciprocating cycle of the wiper 18A). A light reduction ratio is set as the intensity of the light treatment. The wiping speed is calculated according to the amount of movement of the wiper 18A per predetermined time (unit time). The higher the wiping ratio, the higher the strength of the light reduction process, and the higher the light reduction ratio, the stronger the strength of the light reduction process compared to the small light reduction ratio. (brightness is greatly reduced). In addition, in the switching adjustment unit 116, the strength of the dimming process is set when the wiper device 18 is stopped (the wiping speed is zero), and the dimming process at this time is set to the weakest (normally processing).

Next, the dimming process in the imaging device 110 will be described with reference to FIG. 18 . It should be noted that FIG. 18 shows an overview of the dimming process setting executed in the imaging controller 112 in the form of a flow chart.

As shown in FIG. 18, the imaging controller 112 executes steps 200 to 206 and steps 210 and 212 so that both the image captured by the camera 32 and the auto light device 24 have a predetermined brightness around the vehicle 12. and the wiper device 18 is operated and it is determined that it is raining (affirmative determination in step 212), the process proceeds to step 270.

At step 270, the imaging controller 112 obtains the speed of the wiper device 18 being operated. That is, it acquires whether the wiper device 18 is operated in the intermittent mode or the continuous mode, the intermittent time in the intermittent mode, and the wiping speed in the continuous mode (high speed or low speed, etc.), and decreases based on the acquired wiping speed. Set the light ratio. Next, in step 272, the imaging controller 112 sets the dimming process so that the process is performed with the intensity set according to the dimming ratio.

After setting the dimming process and the intensity of the dimming process in the luminance adjustment in this way, the imaging controller 112 executes steps 216 to 226, and when each of steps 218, 222, and 226 makes an affirmative determination, , go to step 208 (return to normal processing). If the wiper device 18 is stopped while the determination in step 218 or step 222 is negative, the imaging controller 112 sets the wiping speed to the lowest value (for example, 0) and continues the dimming process.

Here, when the wiper device 18 operates, if the period of the wiper 18A is short, the interval between changes in brightness caused by the scattering of light and the shadow of the wiper 18A becomes short. For this reason, when the wiping speed of the wiper device 18 is high (high), compared to when the wiping speed is low (low), flickering in the photographed image tends to increase, and the change in brightness tends to increase. can be annoying when viewed.

In this manner, the imaging apparatus 110 performs light reduction processing on the captured image when it is estimated that the environmental state makes the captured image visually dazzling. As a result, even if the headlights of an oncoming vehicle are turned on, the driver does not feel glare when viewing the photographed image.

Further, in the imaging device 110 , light reduction processing is performed with strength based on the wiping speed of the wiper device 18 . At this time, when the wiping speed is high, the strength of the dimming process is made stronger than when the wiping speed is low. As a result, it is possible to reduce the change in brightness that occurs in the captured image, and the user does not feel annoyed when viewing the captured image.

[Eighth embodiment]
Next, an eighth embodiment of the invention will be described. In the eighth embodiment, functional components that are the same as those in any one of the first to seventh embodiments will be given the same reference numerals as the corresponding functional components in any one of the first to seventh embodiments, and will be described in detail. omitted.

FIG. 18 shows a schematic configuration diagram of an imaging device 120 according to the eighth embodiment.
As shown in FIG. 18 , the imaging device 120 is provided with an imaging controller 122 , and the imaging controller 122 is formed with an adjustment switching section 124 . The imaging apparatus 120 according to the eighth embodiment has an adjustment switching unit 124 in the imaging controller 122 instead of the adjustment switching unit 116 of the imaging controller 112 according to the seventh embodiment. It differs from device 110 .

An image captured by the camera 32 is input to the adjustment switching unit 124 of the imaging controller 122 . Further, in the imaging device 120 , the wiper device 18 is connected to the adjustment switching section 124 . Furthermore, the imaging device 120 may be connected to a defogger device 126 that operates as an anti-fogging device for the windshield 16F.

The adjustment switching unit 124 acquires (monitors) an image captured by the camera 32 that captures an image of the front of the vehicle through the windshield 16F, and averages the brightness (luminance) of the captured image at predetermined time intervals while the wiper device 18 is not operating. Calculate the value (non-operating average value). Further, when the wiper device 18 is operated, the adjustment switching unit 124 calculates the average value of the brightness of the photographed image at predetermined time intervals during the operation of the wiper device 18 (operating average value). At this time, the predetermined time interval is set to be shorter than one cycle of the wiping operation of the wiper 18A in the wiper device 18. As shown in FIG.

When setting the light reduction processing for the captured image, the adjustment switching unit 124 compares the non-operating average value and the operating average value of the captured image (contrast the brightness), and determines the peak (maximum value) of the difference obtained by the comparison. When the value exceeds a preset threshold value and the interval between peaks is synchronized with the wiping period of the wiper device 18, the dimming process is set to be performed.

Next, the dimming process in the imaging device 120 will be described with reference to FIGS. 20 and 21. FIG. Note that FIG. 20 shows a flow chart showing an outline of the dimming process setting executed in the imaging controller 122, and FIG. A schematic representation of the resulting brightness variation is shown in the diagram. In FIG. 21, the horizontal axis represents time, and the vertical axis represents the brightness (average luminance value) of the captured image.

As shown in FIG. 20, the imaging controller 122 executes steps 200 to 206 and steps 210 and 212 so that both the captured image of the camera 32 and the auto light device 24 have a predetermined brightness around the vehicle 12. and the wiper device 18 is operated and it is determined that it is raining (affirmative determination in step 212), the process proceeds to step 280.

In step 280, the imaging controller 122 calculates an operating average value of the brightness when the wiper device 18 is operating from the image captured by the camera 32, and the calculated operating average value and the brightness calculated before the wiper device 18 is operated. and non-operating average values set aside. In step 282, the imaging controller 122 acquires a cycle (anti-glare cycle) at which the difference between the non-operating average value and the operating average value is equal to or greater than a preset threshold value. At this time, the threshold value can be set based on the average brightness value (lower limit value) of the photographed image that causes glare with respect to the non-operating average value.

After acquiring the anti-glare cycle, the imaging controller 122 determines in step 284 whether or not the anti-glare cycle and the wiping cycle of the wiper 18A are synchronized. At this time, if the anti-glare period and the wiping period are not synchronized, the imaging controller 122 makes a negative determination in step 284 and proceeds to step 208 .

On the other hand, if the anti-glare period and the wiping period are synchronized, the image pickup controller 122 makes an affirmative determination in step 284 and proceeds to step 286 to perform the dimming process (dimming process). processing).

After that, the image pickup controller 122 proceeds to step 208 when a positive determination is made in each of steps 218 and 222 or a negative determination is made in step 284 because the wiper device 18 is stopped.

As shown in FIG. 21, when raindrops or the like are attached to the windshield 16F at night and the wiper device 18 operates, the average value of brightness (average value during operation) is synchronized with the wiping operation of the wiper 18A. and the difference from the non-operating average exceeds the threshold. At this time, the wiping residue of the wiper 18A forms a water film or the like, which increases the average value during operation. In addition, since the wiper 18A is reflected in the photographed image, the wiper 18A forms a shadow and the average value during operation is lowered.

Therefore, it can be determined whether the change in the brightness of the captured image is caused by the operation of the wiper device 18 from the change in the average value of the brightness of the captured image. Also, if the change in the average brightness of the captured image affects the operation of the wiper device 18, the cycle (anti-glare cycle) approximates the wiping cycle of the wiper 18A.

From this, the imaging controller 122 performs light reduction processing on the captured image when it can be determined that the anti-glare cycle and the wiping cycle are synchronized. As a result, even if the wiper device 18 operates, it is possible to prevent glare from occurring when the photographed image is displayed.

As described above, in the imaging device 120, even if the wiper device 18 is operated in a case where it is estimated that the environmental condition is such that the captured image is perceived as being dazzling, the captured image is perceived as dazzling. You can prevent it from happening.

On the other hand, the vehicle 12A is provided with a defogger device 126, and by operating the defogger device 126, the defogging of the windshield 16F can be promoted. From here, the imaging device 120 operates the defogger device 126 when performing the dimming process. As a result, it is possible to effectively suppress glare from occurring in the captured image.

Note that the rear glass 16R is often provided with a rear defogger. From this, when capturing an image behind the vehicle through the rear glass 16R, by activating the rear defogger in accordance with the dimming process, glare in the captured image can be effectively suppressed.

In the above-described first to eighth embodiments, automobiles such as the vehicles 12 and 12A are used as examples of vehicles. However, the vehicle may be any vehicle provided with a wiper device on the windshield, and may be a train such as an electric locomotive.

Further, in the first to eighth embodiments described above, the programs executed by the display controllers 30, 52, 62, 82, 92, and 102 and the imaging controllers 108, 112, and 122 are installed in ROM or storage in advance. may have been In addition, these programs are provided in the form recorded on recording media such as CD-ROM (Compact Disk Read Only Memory), DVD-ROM (Digital Versatile Disk Read Only Memory), and USB (Universal Serial Bus) memory. Alternatively, it may be downloaded from an external device via a network.

In addition, it is not limited to the above-described first to eighth embodiments, and various modifications can be made without departing from the scope of the invention. For example, even if all or part of the components of the display controllers 30, 52, 62, 82, 92, 102 and the imaging controllers 108, 112, 122 are integrated with the inner mirror 28 or the camera 32, the gist of the present invention is not lost.

10, 50, 60, 80, 90, 100, electronic mirror system 16F windshield (wind glass)
16R rear glass (window glass)
18 wiper device (environment detection means)
20 rear wiper device 24 auto light device (environment detection means)
26 imaging device 28 inner mirror (display means, image display device)
30, 52, 62, 82, 92, 102 Display controller (image display device, image processing device)
32 camera (imaging means, environment detection means)
38, 70 environment detection unit (environment detection means)
40, 54, 64, 114 luminance adjustment unit (adjustment means)
68, 84, 116, 124 adjustment switching units 104, 110, 120 imaging devices 108, 112, 122 imaging controller (image processing device)

Claims (7)

display means for displaying a display image corresponding to a photographed image of one side outside the vehicle taken through the window glass by the imaging means;
Detecting an environmental condition from which it can be estimated whether or not water droplets adhere to the window glass, and an environmental condition from which it can be estimated whether or not the water droplets adhering to the window glass affect the brightness of the image captured by the imaging means. environmental detection means for
When the environmental state detected by the environment detection means is estimated to be water droplets adhering to the windshield and the water droplets adhering to the windshield are presumed to affect the brightness of the display image, Compared to the case where it is not estimated that water droplets adhere to the window glass in the environmental state detected by the environment detection means or that the water droplets adhered to the window glass affect the brightness of the display image. adjusting means for adjusting the brightness of the displayed image;
An image display device including The environment detection means includes a brightness detection means for detecting the brightness outside the vehicle, and a wiper device that wipes off water droplets adhering to the windshield when operated,
2. The image display device according to claim 1, wherein said adjusting means suppresses the brightness of said display image when the brightness outside the vehicle is below a predetermined brightness and said wiper device is operated. 3. The image display device according to claim 1, wherein, when the display image is displayed on the display means, the adjustment means suppresses the brightness of the display image by suppressing the luminance of the display image. 4. The image display device according to any one of claims 1 to 3, wherein the adjustment means suppresses the brightness of the display image by suppressing the brightness of the display means. 3. The image display device according to claim 1, wherein the adjustment means suppresses the brightness of the displayed image by reducing the brightness of the image displayed on the display means. an imaging means for imaging one side outside the vehicle through the window glass;
Detecting an environmental condition from which it can be estimated whether or not water droplets adhere to the window glass, and an environmental condition from which it can be estimated whether or not the water droplets adhering to the window glass affect the brightness of the image captured by the imaging means. environmental detection means for
When the environmental state detected by the environment detection means is estimated to be water droplets adhering to the windshield, and the water droplets adhering to the windshield are presumed to affect the brightness of the image captured by the imaging device. (b) when it is not estimated that water droplets adhere to the windshield in the environmental state detected by the environment detection means, or water droplets adhered to the windshield do not affect the brightness of the photographed image; adjusting means for adjusting so as to suppress the brightness of the captured image;
An imaging device comprising: Environment detection for detecting an environmental condition that enables estimation of whether or not water droplets adhere to the windshield, and an environmental condition that permits estimation of whether or not the water droplets adhered to the windshield affect the brightness of the image captured by the imaging means. means and
For a photographed image in which one side outside the vehicle is photographed through the window glass by the imaging means,
When the environmental state detected by the environment detection means is estimated to be water droplets adhering to the windshield and the water droplets adhering to the windshield are presumed to affect the brightness of the photographed image, Compared to the case where it is not estimated that water droplets adhere to the windshield in the environmental state detected by the environment detection means, or that the water droplets adhered to the windshield do not affect the brightness of the photographed image. an adjusting means for performing adjustment so as to suppress the brightness of the captured image;
image processing device including

Images