JPH09214827A - On-vehicle camera equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To pick up clearly an object even under an unpreferable image pickup condition such as back light by masking excess light made incident from an object with high luminance in existing in a visual field. SOLUTION: Excess light made incident from an object with high luminance existing in a visual field is masked. In this equipment, a controller 5 includes a division means, a high luminance area detection means, an area arithmetic means and a luminance averaging means. A luminance signal obtained from a CCD 3 is given also to the dividing means and the luminance signal is classified into 6×6 groups corresponding to segments 31. The segment information denoting the luminance to be a prescribed luminance or over detected by the high luminance area detection means is given to the area arithmetic means. The arithmetic result by the area arithmetic means is given to the luminance averaging means. The luminance averaging means generates a control signal voltage and gives it to segments of a prescribed area of a liquid crystal display panel 4 so as to reduce the transmittivity of light of the area thereby averaging the luminance of the entire image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera mounted on an automobile.

[0002]

2. Description of the Related Art In recent years, a CCD camera (camera using a solid-state image pickup device) is mounted on an automobile and attempts have been made to safely drive the automobile such as recognizing a white line on a traveling road and detecting an obstacle. Further, in such a camera device,
Simplification of a diaphragm device for adjusting the light quantity and an actuator for driving the diaphragm device is being studied. An example of such a camera device is, for example, Japanese Patent Laid-Open No. 63-5487.
Japanese Patent Publication No. 7-No. The device of this publication uses liquid crystal as a diaphragm device. In this device, the disc-shaped liquid crystal is divided into a plurality of concentric circles, and the light transmittance of the portion divided by the concentric circles is changed according to the amount of light. As a result, the brightness of the entire image is adjusted without using a complicated diaphragm device.

[0003]

By the way, this type of camera device is fixedly attached to the vehicle body so as not to cause shake due to running of the vehicle. Therefore, it is impossible to avoid this by changing the direction of the camera even in situations such as backlit conditions or when the sun is within the angle of view. This is often encountered in the morning and evening, and in such cases halation and smear may occur, making it difficult to recognize the front. For example, an image may be extremely bright in the sun part and extremely dark in the other part when the sky is extremely bright against the sun or in a scene where the sun is incident. Also, when the vehicle is approaching the exit of the tunnel, the image may be completely white. Therefore, it may be difficult for the camera device to detect a preceding vehicle, a white line, or the like. In such a case, in the conventional camera device, the light amount is reduced by the diaphragm device. However, the conventional camera device controls the brightness of the entire image by changing the aperture diameter of the diaphragm device according to the brightness of the entire image (average photometry) or a specific portion (partial photometry) near the center of the image. Therefore, although it is possible to control the brightness of the entire image, it is not possible to deal with the difference in brightness within the angle of view such as a region where the brightness is extremely high as described above, and it is not a sufficient backlight countermeasure. There wasn't.

The present invention has been made in order to solve such a problem, and not only in a normal backlit state, but also in an undesired photographing condition in which an object of high brightness such as the sun exists within the angle of view. The objective is to obtain a camera device that can clearly capture an object.

It is another object of the present invention to improve the reliability of the camera device.

Another object is to simplify the camera device of the present invention.

It is another object of the present invention to reduce the number of parts of the camera device.

[0008]

A vehicle-mounted camera device according to the present invention comprises a light-collecting means for collecting incident light, a light-receiving means for generating a brightness signal according to the intensity of the light, and a light-receiving means for receiving light from the light-receiving means. A signal processing unit that calculates a video signal based on a luminance signal, an image display unit that displays an image based on the video signal from the signal processing unit, and a control signal that has a plurality of regions and is arranged in the optical path of light. A light amount adjusting unit that changes the light transmittance of a predetermined region of the plurality of regions according to
A dividing means for dividing the light receiving means into a plurality of areas, a high brightness area detecting means for detecting a high brightness area of the plurality of areas of the light receiving means, and a high brightness area for receiving a detection output of the high brightness area detecting means. Area calculating means for calculating the area of the light quantity adjusting means, and a control signal is supplied to the light quantity adjusting means on the basis of the calculation result of the area calculating means to adjust the light transmittance of a predetermined area, thereby adjusting the entire area of the image. And a brightness leveling means for leveling the brightness.

Further, the vehicle-mounted camera device according to the present invention is
The dividing means divides the light receiving means into a plurality of grid-like regions.

Further, the vehicle-mounted camera device according to the present invention is
The dividing means divides the light receiving means into a plurality of regions horizontal to the image.

Further, the vehicle-mounted camera device according to the present invention is
The brightness leveling means controls the light quantity adjusting means so that the light transmittance gradually decreases as the area approaches the high brightness area.

Further, the vehicle-mounted camera device according to the present invention is
Light collecting means for collecting incident light, light receiving means for generating a luminance signal according to the intensity of light, signal processing means for calculating a video signal based on the luminance signal from the light receiving means, and this signal processing means Image display means for displaying an image based on a video signal from the device, and having a plurality of regions and arranged in the optical path of light to change the light transmittance of a predetermined region among the plurality of regions according to a control signal. A light quantity adjusting means, a high brightness area detecting means for detecting a high brightness area based on a brightness signal of the light receiving means, and a light quantity adjusting means area corresponding to the high brightness area by receiving a detection output of the high brightness area detecting means. The area calculation means and the brightness leveling means for leveling the brightness of the entire image by supplying a control signal to the light amount adjusting means based on the calculation result of the area calculation means to adjust the light transmittance of a predetermined area. Prepared Than it is.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

 Embodiment 1 FIG.

FIG. 1 is a configuration diagram showing a schematic configuration of the first embodiment. In FIG. 1, 1 is a camera body, 2 is a lens as a condensing means for condensing incident light, 3 is a CCD (charge coupled device) as a light receiving means arranged at the focal point of the lens 2, and The formed image is photoelectrically converted according to the intensity of the light to generate a luminance signal. CCD
The luminance detection of No. 3 is divided into a plurality of grid-like regions as shown in the figure. In the example shown in the figure, the CCD 3
The light receiving surface of is divided into six equal parts both in the horizontal and vertical directions. In the figure, what is indicated by 31 is this divided segment. In this case, the number of divisions may be arbitrary, and may be different between horizontal and vertical. It should be noted that this CCD is not special and is not actually physically divided. This is exactly the same as the conventional CCD, and only detects the brightness for each segment. 4 is
A liquid crystal plate as a light quantity adjusting unit arranged in front of the lens 2 with a distance L, and is arranged in the optical path of light incident on the camera device. In the illustrated example, the liquid crystal plate 4 is CC
It is divided into the same number of areas as D3, and its shape is CCD
Similar or identical to 3. 41 indicates the segment. The segment 41 and the CCD segment 31 are arranged in point symmetry with the lens 2 as the origin. Further, to the segment 41 of the liquid crystal plate 4, a voltage as a control signal is independently applied to each segment, and the transmittance of each segment can be freely adjusted independently.

Reference numeral 5 denotes a controller, which applies a control signal to the liquid crystal plate 4 in accordance with the brightness of the CCD 3 to drive the liquid crystal plate 4 to change its transmittance. The controller 5 also includes signal processing means (not shown) for processing the luminance signal from the CCD 3 to obtain a video output as a video signal. The video signal calculated by this signal processing means is sent to the display 6 as an image display means. The display 6 receives this video output and displays an image on the screen.

The controller 5 also includes a dividing means, a high brightness area detecting means, an area calculating means and a brightness leveling means, which are not shown. The luminance signal obtained from the CCD 3 is also given to the dividing means. The dividing means classifies the luminance signals into groups of 6 × 6 corresponding to the segments 31. This is because, when the CCD 3 is scanned, the luminance signal of the pixel is sorted according to the information of which region of the lattice-shaped region the pixel currently scanned is.
The luminance signal sorted by the dividing means is given to the high luminance area detecting means. With this high-brightness area detection means, 6
Based on the brightness information of the × 6 segments, a segment having a predetermined brightness or higher is detected. This predetermined brightness is set to an arbitrary brightness that makes it difficult to recognize the image of the object when it exists within the angle of view as described in the above problem. The information of the segment with a predetermined brightness or higher detected by the high brightness area detection means is
It is given to the area calculation means. The area calculation means calculates the segment of the liquid crystal plate 4 corresponding to the segment having the predetermined brightness or higher, in this case, the segment of the liquid crystal plate 4 located at a point symmetry centered on the lens 2. The calculated segment of the liquid crystal plate 4 constitutes a predetermined area. In addition,
This calculation may be performed by a storage unit that stores the segment of the CCD and the segment of the liquid crystal plate, which are located in point symmetry with respect to the lens 2, in association with each other. The calculation result of the area calculation means is given to the luminance leveling means. The brightness leveling means generates a control signal by voltage and supplies the control signal to a segment of a predetermined area of the liquid crystal plate 4 to reduce the light transmittance of the area, thereby leveling the brightness of the entire image.

Next, the operation will be specifically described. FIG.
5 to FIG. 5 are explanatory diagrams of the operation of this camera in a typical scene of a scene, in which (a) is the scene of the scene and (b) is the brightness state of the segment 31 of the CCD 3 in common with each drawing. ,
(C) shows the state of the transmittance of each segment 41 of the liquid crystal plate 4,
(D) shows an image displayed on the display 6. Further, 7 indicates a preceding vehicle to be photographed, and 8 indicates a white line drawn on the road surface. For convenience of explanation, each segment 31 of the CCD 3 has an X column in the horizontal direction with the lower right corner as a reference.
From right to left, 1, 2, 3, ..., Vertical direction is Y row, and from bottom to top, 1, 2, 3 ,. . Similarly, the names of the segments 41 of the liquid crystal plate 4 are based on the upper left corner, the horizontal direction is P columns, the direction from left to right is 1, 2, 3, ..., And the vertical direction is Q rows. , And from top to bottom are called 1, 2, 3, ....
The arrangement of the segments 31 of the CCD 3 in (b) and the arrangement of the segments 41 in the liquid crystal plate 4 in (c) are as viewed from the direction of the arrow in FIG. In addition, CCD3
And the numbering on the liquid crystal plate 4 is reversed is CCD
This is because the image formation on 3 is inverted due to the action of the lens 2.

FIG. 2 is a diagram for explaining the operation at the time of normal light or oblique light. In this case, the sky part is slightly brighter than the other parts, and there is no extreme difference in brightness. That is,
The brightness of each of the segments 31 of the CCD 3 shown in (b) is somewhat higher than the brightness of the Y1 row (hatched portion in the drawing) corresponding to the empty part, and is not higher than the predetermined brightness. In this way, when there is no large difference in brightness in the image,
All the segments 41 of the liquid crystal plate 4 shown in (c) have the same transmittance, and the brightness of the entire screen is uniformly controlled. This control is performed according to the brightness of the entire image, that is, it functions as an auto iris like the diaphragm device of the conventional device. Therefore, as shown in (d), the screen displayed on the display 31 has the same brightness distribution as the field shown in (a). In this case, the predetermined area of the liquid crystal plate 4 is
It is all the segments of the liquid crystal plate 4.

FIG. 3 shows the case of backlighting, and it is a case where it is difficult to image the preceding vehicle 7 and the white line 8 satisfactorily because the sky is very bright even if the sun is not incident within the angle of view. . In this case, the segment 31 of the CCD 3 shown in (b) is Y1.
The brightness of the row, that is, the segment of X1Y1 to X6Y1 is very high and exceeds the predetermined brightness. Therefore, the segment from X1Y1 to X6Y1 of the CCD 3 is detected as the high brightness region by the high brightness region detecting means. This information is given to the area calculation means, and the areas of the liquid crystal plate 4 corresponding to these high-brightness areas, that is, the areas of the liquid crystal plate 4 which are in point symmetry with the high-brightness areas of the CCD 3 are calculated. In this case, as shown in (c), Q1 of the liquid crystal plate 4 is
This corresponds to a row, that is, a segment of P1Q1 to P6Q1. The brightness leveling means receives this information, and the liquid crystal plate 4 corresponding to the segment of the CCD 3 determined to be the high brightness region.
A control signal is output so as to reduce the light transmittance of the segment of P1Q1 to P6Q1 to a predetermined transmittance, and the segment is driven. As a result, X1Y1 to X of CCD3
The amount of light incident on the 6Y1 segment is reduced, and (d)
As shown in FIG. 7, the image of the display 6 has a reduced brightness in the sky, and the difference between light and dark in the image is reduced, so that the preceding vehicle 7 and the white line 8 can be clearly photographed.

In this example, when the brightness of the CCD 3 segments is higher than a predetermined brightness, the light transmittance of the segments of the liquid crystal plate corresponding to these segments is uniformly reduced. However, the present invention is not limited to this, and the light transmittance of the segments P1Q1 to P6Q1 of the liquid crystal plate 4 is adjusted according to the brightness of the corresponding segments X1Y1 to X6Y1 of the CCD 3 to further reduce the difference between light and dark in the image. You may do it.

Next, a state in which the images of the preceding vehicle 7 and the white line 8 become black images will be described. FIG. 4 shows a case where the sun 9 is directly in the angle of view, such as in the morning and evening when it is fine. Since the brightness of the sun 9 is extremely high, the difference in brightness between the sun 9 and its surroundings becomes extremely large. That is, the image of the sun 9 and its surroundings becomes an extremely bright image, and conversely, the other preceding vehicles 7 and the white lines 8 become a completely black image. In addition, ghost and flare of the lens, smear of CCD, blooming, and the like are generated, which is a condition in which shooting is impossible. In this case, as shown in (b), the sun 9 is imaged on the segment X2Y1 of the CCD 3, and the brightness of this segment is extremely high. Also, the adjacent segments X1Y1, X3Y1, X
The brightness levels of the 1Y2, X2Y2, and X3Y2 segments are also very high. In this case, as shown in (c), the light transmittance of the segment P2Q1 of the liquid crystal plate 4 corresponding to the segment X2Y1 of the CCD 3 is minimized, and its adjacent segments P1Q1, P3Q1, P1Q2, P2.
The transmittance of each segment of Q2 and P3Q3 is also lowered according to the brightness of each segment of the corresponding CCD3. As a result, as shown in (d), the brightness of the sun 9 and its vicinity is reduced, ghosts, smears, etc. do not occur, and the preceding vehicle 7 which has been black and has been difficult to identify up to now. The white line 8 can be clearly photographed.

Contrary to the case of FIG. 4, the case where the images of the preceding vehicle 7 and the white line 8 are pure white will be described below. Figure 5 shows the case when approaching the exit of the tunnel,
This is a case where it is difficult to recognize because the central area where the preceding vehicle and the white line exist is completely white, because the surrounding dark area is large. In this case, as shown in (b), the luminance of the CCD 3 has the segments X3Y3, X4Y3, X3Y4 and X4Y4.
4 are very high and other segments are low. Therefore, as shown in (c), the corresponding liquid crystal plate 4
Segments P3Q3, P4Q3, P3Q4 and P4Q
The transmittance of the light of No. 4 is lowered, and the brightness leveling means drives so as to maximize the transmittance of other segments. as a result,
As shown in (d), the preceding vehicle 7 and the white line 8 can be clearly recognized.

In the above-described first embodiment, the high brightness area is detected by the absolute brightness indicating whether the brightness of each segment 31 of the CCD 3 is the predetermined brightness or more. However, the difference from the brightness of the adjacent segment is the predetermined brightness or more. The high brightness area may be detected by the relative brightness of whether or not. Further, the high luminance area may be detected based on the luminance ratio instead of the luminance difference.

Further, in the first embodiment, the segment of the liquid crystal plate 4 corresponding to the segment of the high brightness region of the CCD 3 is set as the predetermined region, and the light transmittance of this predetermined region is reduced. However, conversely, the light transmittance of all the segments of the liquid crystal plate 4 is set low, and C
The segment other than the segment of the liquid crystal plate 4 corresponding to the segment of the high brightness region of the CD 3 may be set as the predetermined region, and the light transmittance of this predetermined region may be increased.

Further, in the first embodiment, it has been described that the light transmittance of the segment of the liquid crystal plate 4 corresponding to the segment of the high brightness area of the CCD 3 is uniformly reduced or is controlled according to the brightness of the segment of the CCD 3. However,
Without being limited to this, the light transmittance of the segment corresponding to the high-brightness region is controlled to be low, and the light transmittance of the liquid crystal plate is gradually increased from the segment corresponding to the high-brightness region to the segment other than the high-brightness region. It may be different. The gradual difference is that the light transmittance of the liquid crystal plate may be continuously changed by continuously changing the voltage, or the light transmission may be changed stepwise between the adjacent segments. The rate may be changed stepwise.
By doing so, it is possible to further reduce the difference in brightness and darkness in the image.

Therefore, according to the first embodiment, even in various states, excess light incident from a high-brightness object existing within the angle of view is masked to mitigate the difference in brightness and darkness in the image. And objects such as white lines can be clearly recognized.

Further, according to the first embodiment, since the CCD 3 is finely divided into a lattice shape, the masking of light by the liquid crystal plate 4 can be precisely performed.

Further, according to the first embodiment, the segment 4
Since the liquid crystal plate 4 having 1 is arranged in front of the lens 2, the liquid crystal plate 4 has a function as a front protective glass of the lens 2 when the camera device is housed in the case.

Further, although the liquid crystal plate 4 is arranged in front of the lens 2 in the first embodiment, the liquid crystal plate 4 and the CCD 3 are arranged.
And may be arranged between them. This state is shown in the principal part configuration diagram of FIG. In this case, the protective glass is not effective, but there is an advantage that the entire device can be downsized. Since the liquid crystal plate 4 is between the lens 2 and the CCD 3, the size of the liquid crystal plate 4 is C
Can be smaller than CD3.

Further, the liquid crystal plate 4 may be brought into close contact with the cover glass 10 of the CCD 3. This situation is shown in the component diagram of FIG. In this case, the size of the liquid crystal plate 4 is the same as that of the CCD 3, but there is an advantage that the number of parts is reduced and the structure is simplified.

Further proceeding, the cover glass 1 of the CCD 3
0 may be directly charged with the liquid crystal plate 4 to integrate them. In this case, the number of parts can be further reduced.

Further, in the first embodiment, the example using the liquid crystal plate has been described, but the present invention is not limited to this. For example, an electrochromic plate or the like may be used to transmit light by giving a control signal such as a voltage. Any rate can be used.

Embodiment 2 FIG. The second embodiment is a simplification of the first embodiment. Specifically, in the first embodiment, the CCD 3 and the liquid crystal plate 4 are divided into a plurality of grid-like regions, but in the second embodiment, the number of divisions is reduced to simplify the configuration and processing. There is. That is,
In general, when monitoring the front of a vehicle with an on-vehicle camera device, the brightness of the upper part of the screen and the lower part of the screen are extremely large in most cases when the backlight is difficult to photograph. This is because the camera is attached downward at an angle of depression of a few degrees so that you can shoot from the closest distance to your vehicle. This is shown in FIG. FIG. 8 shows an example of an image in a backlit state, in which the luminance of a strip-shaped portion horizontal to the image shown by the diagonal lines in the upper part of the image is high. Therefore, even if the CCD 3 is not finely divided into a grid like in the first embodiment, the CCD
It is almost sufficient if 3 is divided into a plurality of areas horizontal to the image.

FIG. 9 is a configuration diagram showing the configuration of the second embodiment. In the figure, 11 is a lens and 12 is a diaphragm device. In the second embodiment as well, the liquid crystal plate can be made to have the function of the diaphragm device by changing the light transmittance of the entire liquid crystal plate similarly to the first embodiment, and the diaphragm device can be omitted. Now, an example that can be easily applied to a conventional device having a diaphragm device will be described. A CCD 13 is similar to the CCD 3 of the first embodiment. However, CCD1
3 is different from the CCD 3 in the shape of a plurality of regions divided by a dividing means (not shown). The CCD 13 is divided into a plurality of areas horizontal to the image, the segment 131 is an area corresponding to the lower half of the image, and the segments 132 to 134 are the areas corresponding to the upper half of the image in the horizontal direction. It is divided into equal parts. Reference numeral 14 denotes a liquid crystal plate, which is different from the liquid crystal plate 4 of the first embodiment in the shape of a plurality of regions. The segment 141 is a region corresponding to the lower half of the image, and the segments 142 to 144 are obtained by dividing the region corresponding to the upper half of the image into three equal parts. CC
Segment 131 of D13 and segment 1 of liquid crystal plate 14
41, similarly, the segments 132 to 134 respectively correspond to the segments 142 to 142, and their shapes are similar or the same. Reference numeral 15 is a controller having the same function as the controller 5 of the first embodiment,
A control signal based on a voltage is applied to the liquid crystal plate 14 according to the brightness of the CCD 13 to drive the liquid crystal plate 14 to change its transmittance. Also,
The controller 15 includes signal processing means (not shown) for processing the luminance signal from the CCD 13 to obtain a video output as a video signal. The video signal calculated by this signal processing means is sent to the display 6 as an image display means. The display 6 receives this video output and displays an image on the screen.

The controller 15 classifies the luminance signals obtained from the CCD 13 into four groups by associating them with the segments by a dividing means (not shown). This is a CCD
When scanning 13, the luminance signal of the pixel is sorted according to the information of which region of the band-shaped region the pixel currently scanned is. The luminance signal sorted by the dividing means is given to the high luminance area detecting means.
This high-brightness region detecting means detects a segment that is a high-brightness region based on the information on the brightness of the four segments. The segment 131 is an area in which an image taken on the road is formed, and it is unlikely that there is a high-brightness target object that adversely affects the shooting in this area. Therefore, the high-brightness detecting means calculates the ratio of the brightness of the segment 131 to the other segments 132 to 134 with the brightness of the segment 131 as a reference, and when the ratio is equal to or higher than a predetermined ratio, the high-brightness region is determined. recognize. Here, the predetermined ratio is set to an arbitrary ratio that makes it difficult to recognize the image of the object when it is present within the angle of view as described in the above problem. The information on the high-luminance segment detected by the high-luminance region detecting means is given to the region calculating means. In the area calculation means, the liquid crystal plate 14 corresponding to the high brightness segment
Calculate the segment of. The calculated segment of the liquid crystal plate 14 constitutes a predetermined area. The calculation result of the area calculation means is given to the luminance leveling means. The brightness leveling means generates a control signal by voltage and supplies the control signal to a segment of a predetermined area of the liquid crystal plate 14 to reduce the light transmittance of the area, thereby leveling the brightness of the entire image and Alleviates the difference between light and dark.

Therefore, according to the second embodiment, the liquid crystal plate 14
Since the number of the plurality of regions can be reduced, the structure of the liquid crystal plate 14 can be simpler than that of the liquid crystal plate 4.

Further, according to the second embodiment, since the number of plural areas of the CCD 13 can be reduced, the calculation performed by the controller 15 can be simplified, and the load of software can be reduced or the processing speed can be increased.

Further, in the second embodiment, when the high brightness area is detected, the ratio of the brightness with respect to the reference segment 131 is used. However, the present invention is not limited to this, and the difference in brightness between the segments or the first embodiment is used. You may use absolute brightness like this.

In the second embodiment, the light transmittance of the segment of the liquid crystal plate corresponding to the high brightness area is reduced. On the contrary, the light transmittance of the entire liquid crystal plate is set low. Alternatively, the light transmittance of the segment corresponding to a region other than the high brightness region may be increased.

When controlling the segment of the liquid crystal plate corresponding to the high brightness area, hysteresis may be added to the relationship between the brightness of the CCD and the voltage applied to the liquid crystal plate to prevent hunting.

Embodiment 3 The third embodiment is an example in which the second embodiment is further simplified. CCD in the third embodiment
Also, the liquid crystal plate is divided into two parts, the upper part and the lower part of the image. It is a block diagram which shows the structure of Embodiment 3 in FIG.
In the figure, 16 is a CCD, which has two areas as a plurality of areas. The segment 161 is a region corresponding to the upper portion of the image, and the segment 162 is a region corresponding to the lower portion of the image. A liquid crystal plate 17 has two regions as a plurality of regions. The segment 171 is an area corresponding to the upper part of the image, and the segment 172 is an area corresponding to the lower part of the image. The segment 161 of the CCD 16 corresponds to the segment 171 of the liquid crystal plate 17, and the segment 162 of the CCD 16 corresponds to the segment 172 of the liquid crystal plate 17. Reference numeral 18 denotes a controller, which is similar to the controller 15 of the second embodiment.

Since the operation of the third embodiment is substantially the same as the operation of the second embodiment, it will not be described in detail.

Therefore, according to the third embodiment, further simplification of the apparatus, reduction of the load on the software, and higher processing speed can be expected.

Further, the segment 171 and the segment 17
The light transmittance of the liquid crystal plate 17 is gradually changed from the central part of the image to the upper part of the image in accordance with the ratio of the brightness to the value of 2.
The light transmittance may be reduced toward the upper part of the image. Alternatively, segment 171 and segment 17
The light transmittance of the liquid crystal plate 17 is gradually changed from the lower end portion of the image to the upper end portion of the image in accordance with the ratio of the luminance to 2 and the light transmittance is reduced toward the upper portion of the image. Is also good. For example, a method of continuously changing the light transmittance of the liquid crystal plate or changing the light transmittance of the liquid crystal plate in steps can be used. As a result, the difference in brightness between adjacent segments is reduced, and the brightness of the entire image can be more leveled. The above method of lowering the light transmittance at higher luminance and gradually increasing the light transmittance as the luminance lowers is not limited to the third embodiment, and other embodiments are possible. Also, it can be easily applied if necessary.

Embodiment 4 In each of the above embodiments, the CCD is divided into a plurality of areas, but in the fourth embodiment, an example in which the CCD is not divided into a plurality of areas will be described. FIG. 11 is a configuration diagram showing the configuration of the fourth embodiment.
In the figure, 19 is a CCD, 20 is a liquid crystal plate having a plurality of regions finer than those of the above-mentioned embodiment, and 21 is a controller having the same function as that of the above-mentioned embodiment.

The operation of the fourth embodiment is the same as that of the above-described embodiment, but the detection of the high brightness area of the CCD 19 and the driving of the liquid crystal plate 20 are slightly different. 12A and 12B are operation explanatory diagrams of the fourth embodiment, in which FIG. 12A shows the CCD 19 and FIG. 12B shows the liquid crystal plate 20. In (a), 22 indicates a high-luminance region having a predetermined luminance or higher. In (b), 23 is a region of the liquid crystal plate 20 corresponding to the high-luminance region 22, and 24 is a plurality of segments including the region 23. The brightness signal from the CCD 19 is given to the high brightness area detecting means in the controller 21. In this high brightness area detecting means, the brightness signal and the brightness signal are stored in the CCD.
The position of the pixel on 19 is used to detect which pixel has a predetermined brightness or higher, and the high-brightness region 22 shown in FIG.
Is detected. The predetermined brightness is set to an arbitrary brightness that makes it difficult to recognize the image of the object when it exists within the angle of view as described above. Information on pixels having a predetermined brightness or higher, which is detected by the high-brightness region detecting means, is provided to the region calculating means. The area calculation means calculates the segment 24 of the liquid crystal plate 20 corresponding to the pixel having the predetermined brightness or higher. The calculated segment of the liquid crystal plate 20 constitutes a predetermined area. The calculation result of the area calculation means is given to the luminance leveling means. The brightness leveling means generates a control signal by voltage and supplies the control signal to a segment of a predetermined area of the liquid crystal plate 20 to reduce the light transmittance of the area, thereby leveling the brightness of the entire image. In addition,
The reason why the number of the plurality of regions of the liquid crystal plate 20 is large in the fourth embodiment is to finely correspond to the shape of the region 22 of high brightness on the CCD 19. Therefore, if it is not necessary to finely correspond to the shape of the high-brightness region 22, the first embodiment
May be the same number as.

Therefore, according to the fourth embodiment, the CCD 19
It is not necessary to have a dividing means for dividing the area into a plurality of areas.

Also in the fourth embodiment, either absolute brightness or relative brightness may be used when detecting the high brightness region. When using the relative luminance, either the difference in luminance or the ratio of luminance may be used.

Further, the light transmittance of the segment of the liquid crystal plate corresponding to the high brightness region may be reduced, or conversely, the light transmittance of the entire liquid crystal plate may be reduced to correspond to the high brightness region. The light transmittance of the segment other than the selected segment may be increased.

The present invention is not limited to the above embodiments, but the above embodiments may be combined in any manner. Further, various modifications may be made within the scope of the spirit of the present invention.

[0051]

As described above, according to the vehicle-mounted camera device of the present invention, since the excessive light incident from the high-brightness object existing within the angle of view is masked, the difference in brightness and darkness in the image is reduced. Even under unfavorable shooting conditions that are relaxed, the shooting target can be clearly shot.

Further, according to the vehicle-mounted camera device of the present invention, since the light receiving means is divided into a plurality of grid-like regions,
It is possible to precisely mask light incident from a high-brightness object within the angle of view.

Further, according to the vehicle-mounted camera device of the present invention, since the light receiving means is divided into a plurality of areas which are horizontal to the image, it is possible to mask the light incident from a high-brightness object within the angle of view. In addition to the above, the apparatus can be simplified.

Further, according to the vehicle-mounted camera device of the present invention, the light quantity adjusting means is controlled so that the light transmittance gradually decreases as it approaches the portion corresponding to the high brightness area. Can be more relaxed.

Further, according to the vehicle-mounted camera device of the present invention, the excessive light incident from the high-luminance target existing within the angle of view is detected by detecting the high-luminance region without dividing the light receiving means into a plurality of regions. Since the masking is performed, it is possible to clearly photograph the object to be photographed and to simplify the apparatus even under unfavorable photographing conditions.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of a first embodiment.

FIG. 2 is an operation explanatory diagram at the time of normal light or oblique light.

FIG. 3 is an explanatory diagram of an operation during backlighting.

FIG. 4 is an operation explanatory diagram when the sun is directly illuminating within the angle of view.

FIG. 5 is an operation explanatory diagram when a vehicle approaches an exit of a tunnel.

FIG. 6 is a main part configuration diagram showing a modified example of the first embodiment.

FIG. 7 is a component diagram showing a modified example of the first embodiment.

FIG. 8 is an example of an image in a backlit state.

FIG. 9 is a configuration diagram showing a configuration of a second embodiment.

FIG. 10 is a configuration diagram showing a configuration of a third embodiment.

FIG. 11 is a configuration diagram showing a configuration of a fourth embodiment.

FIG. 12 is an operation explanatory diagram of the fourth embodiment.

[Explanation of symbols]

1 camera body, 2 lens, 3 CCD, 4 liquid crystal plate, 5 controller, 6 display, 7 preceding vehicle, 8 white line, 9 sun, 10 cover glass, 11
Lens, 12 diaphragm device, 13 CCD, 14 liquid crystal plate, 15 controller, 16 CCD, 17 liquid crystal plate, 18 controller, 19 CCD, 20 liquid crystal plate, 21 controller, 22 high brightness area, 23
LCD panel area corresponding to high brightness area, 24 LCD panel segments

Claims (5)

[Claims] 1. A light collecting means for collecting incident light, a light receiving means for generating a luminance signal according to the intensity of the light, and a signal processing for calculating a video signal based on the luminance signal from the light receiving means. Means, an image display means for displaying an image on the basis of the video signal from the signal processing means, and a plurality of areas, which are arranged in the optical path of the light and which are arranged in the optical path of the light. A light amount adjusting means for changing the light transmittance of a predetermined area, a dividing means for dividing the light receiving means into a plurality of areas, and a high brightness area detection for detecting a high brightness area of the plurality of areas of the light receiving means. Means, area calculating means for calculating the area of the light quantity adjusting means corresponding to the high brightness area by receiving the detection output of the high brightness area detecting means, and the light quantity adjusting means for the light quantity adjusting means based on the calculation result of the area calculating means. control An in-vehicle camera device, comprising: a brightness leveling unit that levels a brightness of the entire image by supplying a signal and adjusting a light transmittance of the predetermined region. 2. The vehicle-mounted camera device according to claim 1, wherein the dividing unit divides the light receiving unit into a plurality of grid-shaped regions. 3. The vehicle-mounted camera device according to claim 1, wherein the dividing unit divides the light receiving unit into a plurality of regions horizontal to the image. 4. The on-vehicle camera device according to claim 1, wherein the brightness leveling means controls the light quantity adjusting means such that the light transmittance gradually decreases as the portion corresponding to the high brightness area is approached. . 5. A light collecting means for collecting incident light, a light receiving means for generating a luminance signal according to the intensity of the light, and a signal processing for calculating a video signal based on the luminance signal from the light receiving means. Means, an image display means for displaying an image on the basis of the video signal from the signal processing means, and a plurality of areas, which are arranged in the optical path of the light and which are arranged in the optical path of the light. A light amount adjusting means for changing the light transmittance of a predetermined area, a high brightness area detecting means for detecting a high brightness area based on a brightness signal of the light receiving means, and a high brightness for receiving a detection output of the high brightness area detecting means. Area calculating means for calculating the area of the light quantity adjusting means corresponding to the area, and adjusting the light transmittance of the predetermined area by supplying the control signal to the light quantity adjusting means based on the calculation result of the area calculating means. To An in-vehicle camera device further comprising a brightness leveling means for leveling the brightness of the entire image.