JP2002296490A - Range-finding device and camera using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide small-sized and low-cost range-finding device capable of realizing quick focusing. SOLUTION: A distance to a subject OB is obtained by triangular range- finding using the image data of a 1st subject image outputted from a main imaging device 2 and the image data of a 2nd subject image outputted from a sub imaging device 4, to a subject image OB and a focus lens 11 is driven in accordance with the obtained distance. Furthermore, focusing is performed by correcting the position of the lens 11 is accordance with the decided result on the focused state of the main imaging device 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distance measuring apparatus for measuring the distance to a subject by the principle of triangulation to adjust the focus of a main image pickup apparatus, a digital camera using the same, a vehicle-mounted confirmation camera, and The present invention relates to a film camera.

[0002]

2. Description of the Related Art Some conventional digital cameras detect the contrast of a subject image picked up by an image pickup device and use the result to focus on the subject. When focusing is performed by detecting the contrast, it takes a long time to focus, and the subject to be photographed cannot be photographed at a desired timing.

For this purpose, two optical systems and two light receiving sections are provided separately from the image pickup device, and light from the subject is received by the two light receiving sections, and the distance to the subject is measured by triangulation. A digital camera that performs focusing according to a measurement result has been developed. In this case, focusing can be performed in a short time to some extent, and a subject to be photographed can be photographed at a desired timing to some extent.

[0004]

However, in the above-mentioned digital camera, it is necessary to provide two optical systems and two light-receiving parts separately from the image pickup device, which hinders downsizing of the digital camera and increases its cost. Was expensive.

In order to solve the above-mentioned problem, Japanese Patent Application Laid-Open No. H11-122517 discloses a main image pickup device for photographing a subject image which is also used as a part of a distance measuring unit and is provided separately from the main image pickup device. There is disclosed an imaging apparatus that measures a distance to a subject by triangulation using one obtained sub-imaging element, and performs focusing in accordance with a measurement result.

However, even with the above-described triangulation using the main image sensor and the sub image sensor, it is not possible to accurately measure the distance to the subject, so that it takes a certain amount of time for focusing.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a distance measuring device capable of achieving quick focusing, miniaturization and cost reduction, a digital camera using the same, a vehicle confirmation camera, and a film camera. It is to provide.

[0008]

According to a first aspect of the present invention, there is provided a distance measuring apparatus which is separated from a main image pickup device including a main optical system for photographing a subject and an area image pickup device by a predetermined base line length from the area image pickup device. And a sub-imaging device including a sub-optical system and a sub-imaging element arranged at different positions, and using the outputs of the main imaging device and the sub-imaging device to adjust the focus of the main imaging device based on the principle of triangulation. In a distance measuring device that performs, a driving unit that drives the main optical system according to a result of the triangulation,
It is characterized in that it comprises a judging means for judging a focus state by the area image pickup device, and a correcting means for correcting the main optical system according to the judgment result of the judging means.

According to the above configuration, the main optical system is driven in accordance with the result of the triangulation, and the main optical system is corrected in accordance with the result of focus state determination. , The focus can be quickly adjusted, and the size and cost can be reduced.

According to a second aspect of the present invention, in the configuration of the first aspect of the present invention, the determination unit determines the image using an image output during driving of the main optical system by the driving unit. It is characterized by. According to the above configuration, the focus state is determined using the image output during the driving of the main optical system, so that the focus can be adjusted more quickly.

According to a third aspect of the present invention, there is provided a distance measuring apparatus which is disposed at a position apart from the main image pickup device including a main optical system for photographing a subject and an area image pickup device by a predetermined base line length from the area image pickup device. A distance measuring device having a sub-optical system and a sub-imaging device including a sub-imaging device, and performing a focus adjustment of the main imaging device based on a principle of triangulation using an output of the main imaging device and the sub-imaging device; The main optical system includes a focus lens set at a predetermined position when performing the triangulation.

According to the above arrangement, the focus lens is set at a predetermined position when performing triangulation.
Focusing can be quickly performed by detecting the distance to the subject with high accuracy, and downsizing and cost reduction can be achieved.

According to a fourth aspect of the present invention, in the distance measuring apparatus according to the third aspect, the predetermined position is an infinite position. With the above configuration, the focus lens is set to the infinite position when performing triangulation, so that the subject image can be taken in a good condition, and the distance to the subject can be detected with higher accuracy and focus can be achieved. Matching can be performed more quickly.

According to a fifth aspect of the present invention, in the distance measuring apparatus according to the third aspect, the predetermined position is a substantially intermediate position between an infinite position and a closest position. is there. According to the above configuration, the focus lens is set at a substantially intermediate position between the infinite position and the closest position when performing the triangulation, so that the subject image can be photographed in a good state, and The distance can be detected with higher accuracy, and focusing can be performed more quickly.

According to a sixth aspect of the present invention, there is provided a distance measuring apparatus which is disposed at a position apart from the main image pickup device including a main optical system for photographing a subject and an area image pickup device by a predetermined base line length from the area image pickup device. A distance measuring device having a sub-optical system and a sub-imaging device including a sub-imaging device, and performing a focus adjustment of the main imaging device based on a principle of triangulation using an output of the main imaging device and the sub-imaging device; For a subject at a position separated by a predetermined distance, a storage unit that stores in advance information on a positional relationship where the main imaging device and the sub-imaging device capture images is provided. It is characterized in that triangulation is performed according to it.

According to the above arrangement, information on the positional relationship where the main imaging device and the sub-imaging device capture images of a subject at a position separated by a predetermined distance is stored in advance, and according to the stored positional relationship information. Since the triangulation is used to measure the distance to the subject, it is possible to detect the distance to the subject with high accuracy, to quickly perform focusing, and to reduce the size and cost.

According to a seventh aspect of the present invention, in the distance measuring apparatus according to the sixth aspect, the main optical system further includes a zooming mechanism, and the storage means includes a zooming mechanism using the zooming mechanism. A plurality of pieces of information on the positional relationship at the time is stored, and triangulation is performed in accordance with the information on the positional relationship at the time of zooming. According to the above configuration, information on a plurality of positional relationships during zooming by the zooming mechanism is stored,
Since the triangulation is performed according to the stored positional relationship information, the distance to the subject can be detected with high accuracy and the focusing can be performed quickly even during zooming.

According to another aspect of the present invention, the distance measuring apparatus is disposed at a position separated by a predetermined base line length from the main image pickup device including a main optical system for photographing a subject and an area image pickup device. A distance measuring device having a sub-optical system and a sub-imaging device including a sub-imaging device, and performing a focus adjustment of the main imaging device based on a principle of triangulation using an output of the main imaging device and the sub-imaging device; The image processing apparatus further includes a correction unit configured to correct an output difference between an output of the area image sensor and an output of the sub image sensor.

According to the above arrangement, the output difference between the output of the area image sensor and the output of the sub-image sensor is corrected.
Focusing can be quickly performed by detecting the distance to the subject with high accuracy, and downsizing and cost reduction can be achieved.

According to a ninth aspect of the present invention, in the configuration of the distance measuring apparatus according to the eighth aspect, the main optical system further includes a zooming mechanism, and the correcting means includes a zooming mechanism of the zooming mechanism. It is characterized in that the output difference is corrected according to the magnification. According to the above configuration, since the output difference is corrected according to the magnification, the distance to the subject can be detected with high accuracy and the focusing can be performed quickly even during magnification.

According to a tenth aspect of the present invention, the distance measuring apparatus is disposed at a position apart from the main image pickup device including a main optical system and an area image pickup device for photographing a subject by a predetermined base line length from the area image pickup device. A distance measuring device having a sub-optical system and a sub-imaging device including a sub-imaging device, and performing a focus adjustment of the main imaging device based on a principle of triangulation using an output of the main imaging device and the sub-imaging device; The area image sensor includes at least three filters having different spectral sensitivities required for color photographing on each pixel, and the sub-image sensor has a spectral transmittance equal to the spectral transmittance characteristic of the three filters on each pixel. It is characterized by including a filter provided to have characteristics.

According to the above configuration, the spectral transmission characteristics of the area image pickup device and the sub image pickup device are equivalent, so that the distance to the subject can be detected with high accuracy and the focus can be quickly adjusted. Cost and cost can be reduced.

According to another aspect of the present invention, a distance measuring apparatus is provided at a position separated from the area image pickup element by a predetermined base line length from a main image pickup apparatus including a main optical system for photographing a subject and an area image pickup element. A distance measuring device having a light projecting device, and receiving the reflected light of the light emitted from the light projecting device from the subject by the main image sensing device and adjusting the focus of the main image sensing device based on the principle of triangulation A driving unit that drives the main optical system according to the result of the triangulation, a determining unit that determines a focus state by the area image sensor, and the main optical system according to a determination result of the determining unit. And a correcting means for correcting.

According to the above configuration, the main optical system is driven in accordance with the result of the triangulation, and the main optical system is corrected in accordance with the result of the focus state determination. , The focus can be quickly adjusted, and the size and cost can be reduced.

According to a twelfth aspect of the present invention, there is provided a distance measuring apparatus according to the eleventh aspect.
In the configuration of the distance measuring apparatus described above, the determination unit makes the determination using an image output during driving of the main optical system by the driving unit. According to the above configuration,
Since the focus state is determined using the image output during the driving of the main optical system, the focus can be adjusted more quickly.

According to a thirteenth aspect of the present invention, the distance measuring apparatus is disposed at a position apart from the main image pickup device including a main optical system for photographing a subject and an area image pickup device by a predetermined base line length from the area image pickup device. A distance measuring device having a light projecting device, and receiving the reflected light of the light emitted from the light projecting device from the subject by the main image sensing device and adjusting the focus of the main image sensing device based on the principle of triangulation , Wherein the main optical system includes a focus lens which is set at a predetermined position when performing the triangulation.

According to the above arrangement, the focus lens is set at a predetermined position when performing triangulation.
Focusing can be quickly performed by detecting the distance to the subject with high accuracy, and downsizing and cost reduction can be achieved.

According to a fourteenth aspect of the present invention, there is provided a distance measuring apparatus according to the thirteenth aspect.
In the configuration of the distance measuring device described above, the predetermined position is an infinite position. With the above configuration, the focus lens is set to the infinite position when performing triangulation, so that the subject image can be taken in a good condition, and the distance to the subject can be detected with higher accuracy and focus can be achieved. Matching can be performed more quickly.

According to a fifteenth aspect of the present invention, in the thirteenth aspect,
In the configuration of the distance measuring device described above, the predetermined position is a substantially intermediate position between an infinite position and a close position. According to the above configuration, the focus lens is set at a substantially intermediate position between the infinite position and the closest position when performing the triangulation, so that the subject image can be photographed in a good state, and The distance can be detected with higher accuracy, and focusing can be performed more quickly.

A distance measuring apparatus according to a sixteenth aspect of the present invention is arranged at a position separated from the main image pickup device including a main optical system and an area image pickup device for photographing a subject by a predetermined base line length from the area image pickup device. A distance measuring device having a light projecting device, and receiving the reflected light of the light emitted from the light projecting device from the subject by the main image sensing device and adjusting the focus of the main image sensing device based on the principle of triangulation A storage means for storing in advance information on a positional relationship in which the main imaging device receives reflected light of the light projected by the light projection device from the subject at a position separated by a predetermined distance. And triangulation is performed in accordance with the positional relationship information stored in the storage means.

According to the above arrangement, the information on the positional relationship at which the main image pickup device receives the reflected light of the light projected by the light projecting device from the subject at a position separated by a predetermined distance is previously stored. Since the distance is triangulated in accordance with the stored and stored positional relationship information, the distance to the subject can be detected with high accuracy, and the focusing can be quickly performed, and the size and cost can be reduced. Can be.

[0032] The distance measuring device according to the seventeenth aspect is the sixteenth aspect.
In the configuration of the distance measuring device described, the main optical system further includes a zoom mechanism, and the storage unit stores information on a plurality of the positional relationships at the time of zooming by the zoom mechanism,
It is characterized in that triangulation is performed in accordance with information on the positional relationship at the time of zooming. According to the above configuration, information on a plurality of positional relationships at the time of zooming by the zooming mechanism is stored, and triangulation is performed according to the stored information on the positional relationship. The distance can be detected with high accuracy, and focusing can be performed quickly.

[0033] The distance measuring apparatus according to the eighteenth aspect of the present invention is the seventeenth aspect.
The configuration of the distance measuring device according to claim 1, further comprising a correction unit configured to correct a received light image of the main imaging device in accordance with a magnification ratio of the magnification mechanism, and information on a positional relationship stored in the storage unit and the correction unit. Is characterized in that triangulation is performed in accordance with the correction result of According to the above configuration, the received light image of the main imaging device is corrected according to the magnification, and the triangulation is performed according to the positional relationship information and the correction result. The distance can be detected with high accuracy, and focusing can be performed quickly.

A distance measuring apparatus according to a nineteenth aspect of the present invention is arranged at a position separated from the main image pickup device including a main optical system for photographing a subject and an area image pickup device by a predetermined base line length from the area image pickup device. A distance measuring device having a light projecting device, and receiving the reflected light of the light emitted from the light projecting device from the subject by the main image sensing device and adjusting the focus of the main image sensing device based on the principle of triangulation In, storing the output distribution of the area imaging element before the light is projected by the light emitting device,
A light projection image is formed by subtracting a stored output distribution from an output distribution of the area imaging element at the time of light projection by the light projection device.

According to the above arrangement, the output distribution of the area image sensor before light projection is stored, and the stored output distribution is subtracted from the output distribution of the area image sensor at the time of light projection, thereby projecting the projected image. Is formed, the distance to the subject can be detected with high accuracy, focusing can be quickly performed, and downsizing and cost reduction can be achieved.

According to a twentieth aspect of the present invention, there is provided a distance measuring apparatus according to the eleventh aspect.
20. The configuration of the distance measuring device according to any one of claims 19 to 19, wherein the light projecting device is arranged at an oblique position with respect to the main imaging device. According to the above configuration, since the light projecting device is arranged at an oblique position with respect to the main imaging device, the degree of freedom in layout is improved, and the device can be further downsized.

A digital camera according to a twenty-first aspect is provided with the distance measuring device according to any one of the first to twentieth aspects. According to the above configuration, claims 1 to 20
A digital camera having the effect of the distance measuring device according to any one of the above.

According to a twenty-second aspect of the present invention, there is provided a vehicle-mounted confirmation camera, wherein the distance measuring device according to any one of the first to twentieth aspects is provided on a vehicle body. According to the above configuration, it is possible to realize an in-vehicle confirmation camera having the effect of the distance measuring device according to any one of claims 1 to 20.

According to a twenty-third aspect of the present invention, a film type camera is provided with the distance measuring device according to any one of the first to twentieth aspects, and a monitor for displaying a photographed image of the main image pickup device. According to the above configuration, it is possible to realize a film camera having an effect of the distance measuring device according to any one of claims 1 to 20.

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A digital camera will be described below as an example of a camera using a distance measuring apparatus according to an embodiment of the present invention with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a main part of a digital camera according to a first embodiment of the present invention.

The digital camera shown in FIG. 1 has an image pickup optical system 1, a main image pickup element 2, a sub image pickup optical system 3, a sub image pickup element 4, a lens driving section 5, a main image pickup element control section 6, and a sub image pickup element control section 7. , CPU (Central Processing Unit) 8, RAM (Random Access Memory) 9, and EEPROM (Electrically E
rasable Programmable Read-Only Memory) 10.

A main image pickup device is constituted by the image pickup optical system 1 and the main image pickup device 2, and the main image pickup device is arranged at a substantially central portion of the camera body. A sub-imaging device is constituted by the sub-imaging optical system 3 and the sub-imaging element 4, and is arranged at a position separated from the main imaging element 2 by a predetermined base line length.

The imaging optical system 1 includes a focus lens 11 and a boom lens 12. The focus lens 11
A focusing operation is performed by moving in the direction of the optical axis, and focusing on the object OB is performed. Boom lens 12
Performs a zooming operation by moving in the optical axis direction, and performs a zooming operation for enlarging or reducing the subject image of the subject OB.

The main image pickup device 2 is composed of an area image pickup device such as an area type CCD (charge coupled device), and a first object image of the object OB transmitted through the image pickup optical system 1 is formed on the main image pickup device 2. The first subject image is photoelectrically converted to generate an image signal from the accumulated signal charges, and the image signal is output to the main image sensor control unit 6.

FIG. 2 is a diagram schematically showing an example of the configuration of the light receiving section of the main image pickup device 2 shown in FIG. 1. FIG. 3 shows the arrangement of the pixel data created by the light receiving section shown in FIG. FIG.

As shown in FIG. 2, a plurality of light receiving sections (pixels) are arranged in a matrix (i.times.j) in the main image sensor 2, and each of the light receiving sections has different spectral components of R, G, and B. A sensitive filter is formed.

For example, a primary color filter G for transmitting the G component is formed in the light receiving portion G11, and a primary color filter B for transmitting the B component is formed in the light receiving portion B21.
2, a primary color filter R that transmits the R component is formed.
A primary color filter G that transmits the G component is formed in the light receiving unit G22.

Here, the four light receiving portions G in the thick line frame
One pixel data is composed of 11, B21, R12, and G22. This pixel data is defined as s11, and the light receiving unit G1
The data of 1, B21, R12 and G22 are converted to G11 and B2.
1, R12, G22, s11 = G11 + B21 +
R12 + G22. Next, shift only one light receiving part,
Pixel data s21 (= B21 + G31 + G22 + R32) by four light receiving units B21, G31, G22, and R32.
Is created, and thereafter, each pixel data sij (= xij + x (i + 1) j + xi (j
+1) + x (i + 1) (j + 1)), and the arrangement of each pixel data after the creation is as shown in FIG.

Referring again to FIG. 1, the sub-imaging optical system 3
Is formed of a light receiving lens and the like, and forms a second object image of the object OB on the sub-image sensor 4. Sub image sensor 4
Is composed of a line image sensor such as a two-line CCD, photoelectrically converts the second subject image to create an image signal from the accumulated signal charges, and sends the image signal to the sub-image sensor controller 7. Output.

FIG. 4 is a diagram schematically showing an example of the configuration of the light receiving section of the sub-image pickup device 4 shown in FIG. 1. FIG. 5 shows the arrangement of pixel data created by the light receiving section shown in FIG. FIG.

As shown in FIG. 4, a plurality of light receiving sections are arranged in two rows in the sub-image pickup element 4, and each light-receiving section has R, G, , B having different spectral sensitivities.

The four light receiving sections G11, B21, R1
2, G22, one pixel data is formed, and this pixel data is defined as F11, and the light receiving units G11, B21, R1
2 and G22 are converted to G11, B21, R12 and G22.
Then, F11 = G11 + B21 + R12 + G22. Next, four light receiving units B2 are shifted by one light receiving unit.
1, G31, G22, and R32 to generate pixel data F21.
(= B21 + G31 + G22 + R32), and thereafter, each pixel data is similarly shifted by one light receiving unit, and the arrangement of each pixel data after the creation is as shown in FIG.

As described above, since the RGB filters of the sub-image sensor 4 are arranged in the same arrangement as the RGB filters of the main image sensor 2, the spectral transmission characteristics of the main image sensor 2 and the sub-image sensor 4 are the same. Can be The arrangement of the filters of the sub-imaging element 4 may be other arrangements as long as the spectral transmission characteristics of the main imaging element 2 and the sub-imaging element 4 become equal. The same applies to the case where complementary color filters Ye, Mg, G, and Cy are used.

When the main image sensor 2 and the sub image sensor 4 configured as described above are used to image the subject OB at a position separated by a predetermined distance, the main image sensor 2 and the sub image sensor 4 As the positional relationship, for example, when the pixel data s11 shown in FIG. 3 and the pixel data F11 shown in FIG. 5 correspond to each other, the pixel data s11 to S61,. Using the pixel data F11 to F61,... Of the image sensor 4, a distance measurement calculation described later is performed.

Referring again to FIG. 1, the lens driving unit 5
Drives the focus lens 11 and the boom lens 12 under the control of the CPU 8. The main image sensor control unit 6 has a C
Under the control of the PU 8, the CPU 8 controls the operation of the main image sensor 2, performs predetermined processing on the image signal output from the main image sensor 2, and outputs the image signal to the CPU 8. The sub-image sensor control unit 7 controls the operation of the sub-image sensor 4 under the control of the CPU 8, performs predetermined processing on an image signal output from the sub-image sensor 4, and outputs the image signal to the CPU 8.

The CPU 8 reads out and executes a predetermined program stored in the EEPROM 10 to control the operation of each unit and execute a focusing process described later. The RAM 9 is used as a work area for temporarily storing data and the like when the CPU 8 executes a focusing process and the like. The EEPROM 10 stores in advance a program for executing a focusing process and the like, which will be described later, and information on the positional relationship between the main image sensor 2 and the sub image sensor 4 during normal operation and during zooming.

In the present embodiment, the imaging optical system 1 corresponds to the main optical system, the main imaging element 2 corresponds to the area imaging device,
The sub-imaging optical system 3 corresponds to a sub-optical system, the sub-imaging device 4 corresponds to a sub-imaging device, the lens driving section 5 and the CPU 8 correspond to driving means and correcting means, and the main imaging element control section 6 and C
PU8 corresponds to the determination means. In addition, the EEPROM 10
Corresponds to a storage unit, and the zoom lens 12 corresponds to a zoom mechanism. Further, the CPU 8 corresponds to a correction unit.

Next, the focusing process of the digital camera configured as described above will be described. FIG. 6 is a flowchart for explaining the focusing process of the digital camera shown in FIG.

As shown in FIG. 6, first, in step S1, the CPU 8 drives the focus lens 11 by the lens driving section 5, and sets the focus lens 11 to a predetermined position, for example, an infinite position. In this case, the subject image can be photographed in a favorable state. Note that the predetermined position is not particularly limited to this example, and the focus lens 11 may be set at a substantially intermediate position between the infinite position and the closest position.

Next, in step S2, the main image pickup device 2 photoelectrically converts the first object image of the object OB transmitted through the image pickup optical system 1 to accumulate signal charges during a predetermined exposure period, and accumulates signal charges. The imaging device 4 includes the sub-imaging optical system 3
The second subject image of the subject OB that has passed through is photoelectrically converted to accumulate signal charges.

Next, in step S3, the main image sensor 2 sequentially reads the accumulated signal charges vertically and horizontally, and the main image sensor controller 6 converts the read image signal of the first subject image into a digital signal. The image data of the first subject image is output to the CPU 8. The sub-image sensor 4 sequentially reads out the stored signal charges for each pixel, and the sub-image sensor controller 6 converts the read image signal of the second object image into a digital signal, and outputs the second object image. The image data of the image is output to the CPU 8.

Next, in step S4, the CPU 8
Corrects the output difference between the input image data of the first subject image and the image data of the second subject image.

For example, at normal times, the output difference is corrected as follows. FIG. 7 shows the first and second uncorrected states in the normal state.
FIG. 8 is a diagram showing waveforms of the image data of the first and second subject images after the difference conversion at the normal time, and FIG. 9 is a diagram showing the waveforms of the image data of the first and second subject images after the normal conversion. FIG. 8 is a diagram showing a waveform based on image data of a second subject image after correction of the second embodiment. Note that each image data is a discrete digital value. In FIGS. 7 to 9, for ease of explanation, the vertical axis indicates the value of the image data, and the horizontal axis indicates the position on each image sensor. This figure shows a waveform in which discrete values are smoothly connected, and the same applies to other waveform diagrams.

The waveform shown in FIG. 7A is output from the main image sensor 2 as image data of the first object image, and the waveform shown in FIG. 7B is used as image data of the second object image. When output from the image sensor 4, the CPU 8 performs a difference conversion on each waveform, and the image data of the first subject image after the difference conversion has a waveform shown in FIG. The image data of the subject image has a waveform shown in FIG. At this time, as shown in FIG. 8, the offset component of each waveform is canceled.

Next, the CPU 8 adjusts the waveform Lr of the waveform shown in FIG. 8A to the amplitude Ls of the waveform shown in FIG. / Ls times. As a result, the image data of the second subject image after the correction has the waveform shown in FIG. 9, and the amplitude of the waveform of the image data of the second subject image after the correction is the first waveform shown in FIG. Of the image data of the subject image. In this way, the output difference between the image signal of the first subject image output from the main image sensor 2 and the image signal of the second subject image output from the sub image sensor 4 is corrected.

At the time of zooming using the zoom lens 12, the output difference is corrected as follows. FIG.
FIG. 11 is a diagram showing waveforms based on image data of the first and second subject images before correction at the time of zooming, and FIG. 11 is a diagram showing a waveform obtained by compressing the image data of the first subject image shown in FIG. FIG. 12 is a diagram showing a waveform obtained by interpolating the image data of the second subject image shown in FIG. 10 to 1
In FIG. 2, white circles indicate pixel data, and black circles in FIG. 12 indicate interpolation data.

At the time of zooming, for example, when the telephoto magnification is twice the wide angle, the image data of the second subject image shown in FIG. 10B is the first image data shown in FIG. And the resolution of the sub-image sensor 4 becomes half the resolution of the main image sensor 2.

For this reason, the image data of the first subject image is compressed based on the center of the area according to the magnification, and in this case, the image data of the first subject image is compressed as shown in FIG. The compression is performed by half with respect to the center M. Therefore, as shown in FIGS. 11 and 10B, the pitch of the image data of the first subject image matches the pitch of the image data of the second subject image. After that, the difference conversion and the output difference correction are performed as in the normal case.

As another method, the image data of the second subject image is interpolated according to the magnification ratio, and in the above case, the interpolation is performed between the pixel data of the second subject image as shown in FIG. Create data. Also in this case, as shown in FIGS. 10A and 12, the pitch of the image data of the first subject image and the pitch of the image data of the second subject image match. After that, the difference conversion and the output difference correction are performed as in the normal case.

As described above, even at the time of zooming, the output of the image signal of the first subject image output from the main image sensor 2 and the image signal of the second subject image output from the sub image sensor 4 are performed. The difference is corrected.

Next, in step S5, the CPU 8
Calculates a distance to the object OB by performing a correlation operation between the corrected image data of the first object image and the image data of the second object image. FIG. 13 is a diagram showing waveforms of image data of the first and second subject images for explaining the correlation calculation processing by the CPU 8 shown in FIG.

The CPU 8 most correlates with the waveform of the image data of the first subject image shown in FIG. 13A from the waveform of the image data of the second subject image shown in FIG. A portion having a high degree, that is, a waveform in the rectangle shown in FIG. 13B is extracted, and the position of the image data of the extracted waveform on the sub-image sensor 4 is specified.

Here, the EEPROM 10 stores in advance information on the positional relationship between the main image sensor 2 and the sub image sensor 4 when the object OB located at a position separated by a predetermined distance is imaged. FIG. 14 is a schematic diagram illustrating an example of a positional relationship between the main image sensor 2 and the sub image sensor 4 in a normal state.

An object O located at a position separated by a predetermined distance
Sub image sensor 4 with respect to main image sensor 2 when B is imaged
14 has, for example, the positional relationship shown in FIG. 14, and the position S of the sub-image sensor 4 is 6.5 on the main image sensor 2 in the x direction.
And the position moved by 7.5 in the y direction,
These values are stored in advance in M10.

Therefore, based on this positional relationship, the positional deviation of the image data on the sub-image sensor 4 obtained by the above-described correlation operation is obtained, and the object O is obtained by using the well-known principle of triangulation.
The distance to B can be calculated.

At the time of zooming using the zoom lens 12, the positional relationship is stored in the EEPROM 10 in advance as follows. FIG. 15 is a schematic diagram illustrating an example of a positional relationship between the main image sensor 2 and the sub image sensor 4 during zooming.

For example, the position of the sub image sensor 4 with respect to the main image sensor 2 when a subject OB located at a position separated by a predetermined distance at a magnification of 2 times is changed by changing the magnification.
Are doubled, resulting in the positional relationship shown in FIG. That is, the position S of the sub image sensor 4 is
These values are stored in the EEPROM 10 in advance corresponding to the positions moved 3.5 in the x direction and 7 in the y direction.

Further, as described above, the relative sensitivity of the sub-image pickup device 4 is doubled by the magnification change, and a portion not used is formed. For this reason, the use area of the sub-image sensor 4 is limited to the positions S to E, and the position E of the sub-image sensor 4 is a position on the main image sensor 2 which is 17.5 in the x direction and 7 positions in the y direction. , These values are also stored in the EEPROM 10 in advance.

Therefore, even at the time of zooming, the positional deviation of the image data on the sub-image pickup device 4 obtained by the above-described correlation operation based on the above-mentioned positional relationship is obtained, and the subject is subject to the known triangulation principle. The distance to the OB can be calculated.

Next, at step S6, the CPU 8
Calculates the drive amount of the focus lens 11 that matches the distance to the object OB determined in step S5, and sets the focus lens 1 by the lens drive unit 5 according to the calculated drive amount.
1 is driven.

Next, in step S7, the CPU 8
Detects a contrast by a known hill-climbing method using an image signal of a subject imaged by the main image sensor 2 after the focus lens 11 is driven in step S6, and detects a defocus amount of the main image sensor 2. Thereby, the focus state is detected.

Next, in step S8, the CPU 8
Determines whether the defocus amount detected in step S7 is larger than a predetermined value. If the defocus amount is larger than the predetermined value, step S6 is performed to re-focus.
The subsequent processing is repeated, and if the amount of defocus is not larger than the predetermined value, the focus is sufficiently focused, and the processing ends.

As described above, in the present embodiment, the focus lens 11 is driven in accordance with the result of triangulation using the main image sensor 2 and the sub image sensor 4 and the like, and the focus state determination result is obtained. , The position of the focus lens 11 is corrected, so that the focus lens 11 can be adjusted with high accuracy with respect to the subject OB, and the focusing can be performed quickly, and the size and cost can be reduced. be able to.

In the processing of steps S6 to S8, the focus state is detected after the focus lens 11 is moved by a drive amount suitable for the distance to the object OB. However, the present invention is not limited to this example. The object may be imaged by the main image sensor 2 at a predetermined period while the lens 11 is moving, and the focus state may be detected at a predetermined period using the image signal of the imaged object. In this case, focusing can be performed more quickly.

Next, a digital camera according to a second embodiment of the present invention will be described. FIG. 16 is a block diagram showing a configuration of a main part of a digital camera according to the second embodiment of the present invention.

The difference between the digital camera shown in FIG. 16 and the digital camera shown in FIG. 1 is that the sub-imaging optical system 3, the sub-imaging element 4, and the sub-imaging element control section 7 for performing a passive type distance measuring operation. , The CPU 8 and the EEPROM 10 perform an active type distance measuring operation, a light projecting optical system 21, a light projecting element 22, a light projecting element control unit 23, a CPU 8a and an EEPROM.
The difference is that the ROM 10a has been changed.
Are the same as those of the digital camera shown in FIG. 1, the same reference numerals are given to the same parts, and only different points will be described in detail below. Note that, in the present embodiment, the main image sensor is not referred to as the image sensor 2 and the main image sensor control unit is referred to as the image sensor control unit 6 because the sub image sensor and the like are not provided.

A light projecting device is constituted by the light projecting optical system 21 and the light projecting element 22, and is arranged at a position separated from the image pickup device 2 by a predetermined base line length. The light projecting device is disposed at an oblique position (a position not in the same plane and not in the same vertical plane) with respect to the main imaging device. Thus, by arranging the light projecting device obliquely with respect to the main image pickup device, the degree of freedom of the layout of the light projecting device can be improved, and the lens barrel in which the image pickup optical system 1 is arranged has a cylindrical shape. With such a configuration, the size of the digital camera body can be reduced.

The light projecting element 22 is composed of a light emitting diode or the like, and emits predetermined light. The light projecting optical system 21 includes a light projecting lens and the like, and projects light emitted from the light projecting element 22 to the subject OB. The imaging device 2 includes an imaging optical system 1
An image signal is created from the signal charge accumulated by photoelectrically converting the reflected light image from the subject OB of the light projected on the subject OB by the light projecting element 22 and the accumulated signal charges, and the image signal Output to the image sensor control unit 6. The light emitting element controller 23 controls the light emitting element 2 under the control of the CPU 8a.
2 is controlled.

The CPU 8a reads out and executes a predetermined program stored in the EEPROM 10a to control the operation of each unit and execute a focusing process described later. The EEPROM 10a stores in advance a program for executing a focusing process and the like, which will be described later, and information on the positional relationship of the reflected light on the image sensor 2 during normal and variable magnification.

In the present embodiment, the light projecting optical system 21 and the light projecting element 22 correspond to a light projecting device,
The PU 8a corresponds to a driving unit and a correcting unit, and the image sensor control unit 6 and the CPU 8a correspond to a determining unit.
M10a corresponds to storage means, CPU 8a corresponds to correction means, and the other points are the same as in the first embodiment.

Next, the focusing processing of the digital camera configured as described above will be described. FIG.
17 is a flowchart for explaining focus processing of the digital camera shown in FIG. 16.

As shown in FIG. 17, first, in step S1
In 1, the CPU 8a drives the focus lens 11 by the lens driving unit 5, and sets the focus lens 11 to a predetermined position, for example, an infinite position. In this case, the subject image can be photographed in a favorable state. Further, the predetermined position is not particularly limited to this example, and the focus lens 11
May be set to a substantially intermediate position between the infinite position and the closest position.

Next, in step S12, the image pickup device 2 photoelectrically converts the subject image of the subject OB transmitted through the image pickup optical system 1 during a predetermined exposure period without projecting light by the light projecting device 22, and outputs a signal. Accumulate charge.

Next, in step S13, the image sensor 2 sequentially reads the accumulated signal charges vertically and horizontally, and the image sensor controller 6 converts the read image signal of the subject image into a digital signal. The image data of the subject image is output to the CPU 8a. At this time, the CPU 8a causes the RAM 9 to store the read image data of the subject image.

Next, in step S14, the imaging device 2 photoelectrically converts the subject image and the reflected light image of the subject OB transmitted through the imaging optical system 1 during a predetermined exposure period in a state where the light is projected by the light projecting device 22. To accumulate signal charges.

Next, in step S15, the image sensor 2 sequentially reads the accumulated signal charges vertically and horizontally, and the image sensor controller 6 converts the read image signals of the subject image and the reflected light image into digital signals. And outputs the image data of the subject image and the reflected light image to the CPU 8a. At this time, the CPU 8a causes the RAM 9 to store the read image data of the subject image and the reflected light image.

Next, in step S16, the CPU 8
a reads out the image data of the subject image and the image data of the subject image and the reflected light image from the RAM 9 and subtracts the image data of the subject image from the image data of the subject image and the reflected light image to obtain the image data of the reflected light image create.

For example, normally, image data of a reflected light image is created as follows. FIG. 18 is a diagram showing a waveform based on image data of a subject image in a normal state where light is not projected. FIG. 19 is a diagram illustrating image data of a subject image and a reflected light image in a normal state where light is projected. FIG. 20 is a diagram showing a waveform based on image data of a reflected light image in a normal state.

When the light is not projected, the waveform shown in FIG. 18 is output from the image sensor 2 as image data of the subject image. In the light projection state, the waveform shown in FIG. 19 is taken as the image data of the subject image and the reflected light image. When the signal is output from the element 2, the CPU 8a calculates the waveform shown in FIG.
Is subtracted. As a result, the image data is shown in FIG.
The waveform becomes 0, and image data of only the reflected light image is created.

At the time of zooming using the zoom lens 12, image data of only the reflected light image is corrected as follows. FIG. 21 is a diagram illustrating a waveform based on image data of only the reflected light image before and after zooming, and FIG. 22 is a diagram illustrating a waveform based on the image data of only the reflected light image after correction.

At the time of zooming, for example, when the telephoto magnification is twice the wide-angle, the pixel width of the image data of only the reflected light image is doubled as shown in FIG. For this reason, the image data of only the reflected light image after scaling is compressed based on the center of the area in accordance with the magnification, and in this case, as shown in FIG. The image data is corrected by compressing it to a half with respect to the center M. In this way, the image data of only the reflected light image at the time of zooming is corrected, and the corrected image data is used in subsequent processing.

Next, at step S17, the CPU 8
In a, the distance to the subject OB is calculated by calculating the amount of deviation from the reference position of the image data of only the reflected light image created as described above. More specifically, the CPU 8a
The center of gravity g of the image data of only the reflected light image shown in FIG.
The amount of shift of the center of gravity g from the reference position is determined. Next, the CPU 8a obtains a distance corresponding to the shift amount by known triangulation, and calculates this distance as a distance to the subject OB.

Here, in the EEPROM 10a, the center of gravity of the reflected light on the image sensor 2 when the image of the object OB located at a position separated by a predetermined distance is stored in advance as a reference position. FIG. 23 is a schematic diagram illustrating an example of a reference position on the image sensor 2 in a normal state. FIG. 24 is a diagram illustrating a state where the subject OB moves in a normal state and the reflected light image of the projected light moves on the image sensor 2. It is a schematic diagram which shows an example in the case of having done.

As shown in FIG. 23, when an image of an object OB located at a position separated by a predetermined distance is picked up, a reflected light image RP due to the projected light is formed on the image sensor 2. In this case, the position of the reflected light image RP on the image sensor 2 is
The above positions are 10.5 in the x direction and 7.5 in the y direction, and these values are stored in the EEPROM 10 in advance as reference positions. Also, the reference position at the time of zooming using the zoom lens 12 is E
It is stored in the EPROM 10 in advance.

On the other hand, when the object OB moves, FIG.
As shown in (1), a reflected light image MP due to the projected light is formed on the image sensor 2. In this case, the position of the reflected light image MP on the image sensor 2 is 14.5 and y in the x direction on the image sensor 2.
This is the position moved 7.5 times in the direction. Therefore, based on the principle of triangulation, a corresponding distance is obtained from the difference between the reflected light image RP and the reflected light image MP, that is, the shift amount of the reflected light image with respect to the reference position. O
It is the distance to B.

In the case of the above-mentioned active triangulation method, z = B · f ·
(1 / D) holds. Here, B is a base line length between the imaging element 2 and the light projecting element 22, D is a distance to the object OB, and f is a lens focal length.

At this time, z has an offset c due to a mechanical error or the like, and z = B · f · (1 / D) + c. This offset c can be determined by a fixed point adjustment. That is, assuming that the adjustment distance is d and the position on the image sensor 2 at that time is a, a = B · f · (1 / d) +
c, and c = a−B · f · (1 / d).

When the position of the reflected light from the object OB on the image sensor 2 is b, b = BＢf ・ (1 / D) + c
And 1 / D = (b−c) / (B · f), and the distance D at that time can be obtained. In this way,
In the present embodiment, the distance measuring operation is performed in consideration of a mechanical error or the like.

Also, at the time of zooming using the zoom lens 12, the amount of movement from the reference position is also enlarged in accordance with the magnification. For example, when the magnification is twice, the amount of movement from the reference position is about 2 times.
Double. Therefore, at the time of zooming, the reciprocal of the magnification is multiplied by the deviation amount. For example, when the magnification is twice, the deviation amount is approximately 0.5.
Is multiplied to correct the deviation amount. By calculating the distance to the object OB from the corrected amount of deviation,
Even during zooming, the distance to the object OB can be measured with high accuracy.

Next, in step S18, the CPU 8
In step a17, the drive amount of the focus lens 11 that matches the distance to the object OB calculated in step S17 is calculated, and the focus lens 11 is driven by the lens driving unit 5 according to the calculated drive amount.

Next, at step S19, the CPU 8
a is to detect a contrast by a well-known hill-climbing method using an image signal of a subject imaged by the image sensor 2 after the focus lens 11 is driven in step S18, and to detect a defocus amount of the image sensor 2 To detect the focus state.

Next, in step S20, the CPU 8
a determines whether the defocus amount detected in step S19 is larger than a predetermined value, and if the defocus amount is larger than the predetermined value, repeats the processing in step S18 and thereafter to perform focusing again; If the shift amount is not larger than the predetermined value, the focus is sufficiently focused, and the process ends.

As described above, also in the present embodiment, the focus lens 11 is driven in accordance with the result of triangulation using the image pickup device 2, the light projecting device 22, and the like. Since the position of the focus lens 11 is corrected accordingly, the focus lens 11 can be adjusted with high accuracy with respect to the object OB, and the focusing can be performed quickly, and the size and cost can be reduced. Can be.

In the processing in steps S18 to S20, the focus state is detected after the focus lens 11 is moved by a drive amount suitable for the distance to the object OB. However, the present invention is not limited to this example. Lens 1
The object may be imaged by the image sensor 2 at a predetermined cycle during the movement of 1, and the focus state may be detected at a predetermined cycle using the image signal of the imaged object. In this case, focusing can be performed more quickly.

In each of the above embodiments, the case where the present invention is applied to a digital camera has been described. However, the present invention is not particularly limited to this example. The present invention can be similarly applied to a vehicle-mounted confirmation camera having a distance measuring device, a film-type camera that displays a captured image of a main imaging device on a monitor such as a liquid crystal display device, and the same effect can be obtained. .

[0116]

According to the distance measuring apparatus of the present invention, the main optical system is driven according to the result of the triangulation, and the main optical system is corrected according to the result of the focus state determination. Therefore, the main optical system can be adjusted with high accuracy, focusing can be performed quickly, and downsizing and cost reduction can be achieved. According to the distance measuring device of the second and twelfth aspects, the focus state is determined using the image output during the driving of the main optical system, so that the focusing can be performed more quickly.

According to the distance measuring apparatus of the third and thirteenth aspects, the focus lens is set at a predetermined position when performing the triangulation, so that the distance to the subject is detected with high accuracy and the focusing is performed. Can be performed quickly, and downsizing and cost reduction can be achieved. According to the distance measuring device according to claims 4 and 14, the focus lens is set at an infinite position when performing triangulation.
The subject image can be photographed in a good state, and the distance to the subject can be detected with higher accuracy, and focusing can be performed more quickly. According to the fifth and fifteenth aspect of the invention, the focus lens is set at a substantially intermediate position between the infinite position and the closest position when performing the triangulation, so that the subject image is photographed in a good state. Thus, the distance to the subject can be detected with higher accuracy, and focusing can be performed more quickly.

According to the distance measuring apparatus of the present invention, information on the positional relationship where the main imaging device and the sub-imaging device image the subject at a position separated by a predetermined distance is stored in advance, and the stored position is stored. Since the triangulation is performed according to the information on the relationship, the distance to the subject can be detected with high accuracy, focusing can be performed quickly, and downsizing and cost reduction can be achieved. According to the distance measuring apparatus of the seventh aspect, information on a plurality of positional relationships at the time of zooming by the zooming mechanism is stored, and triangulation is performed according to the stored information on the positional relationship. In this case, the distance to the subject can be detected with high accuracy, and the focusing can be quickly performed.

According to the distance measuring apparatus of the present invention, since the output difference between the output of the area image sensor and the output of the sub-image sensor is corrected, the distance to the subject is detected with high accuracy. Can be performed quickly, and downsizing and cost reduction can be achieved. According to the distance measuring device of the ninth aspect, since the output difference is corrected in accordance with the magnification, the distance to the subject can be detected with high accuracy and the focusing can be performed quickly even during magnification. Can be.

According to the distance measuring apparatus of the tenth aspect, since the spectral transmission characteristics of the area image pickup device and the sub image pickup device become equal, the distance to the subject can be detected with high accuracy and the focus can be quickly adjusted. And a reduction in size and cost can be achieved.

According to the distance measuring apparatus of the sixteenth aspect, the position at which the main imaging device receives the reflected light of the light projected by the light projecting device from the subject at a position separated by a predetermined distance. Since the relationship information is stored in advance and the triangulation is performed in accordance with the stored positional relationship information, the distance to the subject can be detected with high accuracy, and the focusing can be quickly performed. Cost can be reduced. According to the distance measuring apparatus of claim 17, information on a plurality of positional relationships at the time of zooming by the zooming mechanism is stored, and triangulation is performed according to the stored information on the positional relationship. In this case, the distance to the subject can be detected with high accuracy, and the focusing can be quickly performed. According to the distance measuring apparatus of the present invention, the received light image of the main image pickup device is corrected according to the magnification, and the triangular distance is measured according to the positional relationship information and the correction result. In this case, the distance to the subject can be detected with high accuracy, and the focusing can be quickly performed.

According to the nineteenth aspect of the invention, the output distribution of the area image sensor before light projection is stored, and the stored output distribution is subtracted from the output distribution of the area image sensor during light projection. As a result, the projected image is formed, so that the distance to the subject can be detected with high accuracy, focusing can be performed quickly, and downsizing and cost reduction can be achieved. According to the distance measuring apparatus of claim 20,
Since the light projecting device is arranged at an oblique position with respect to the main image pickup device, the degree of freedom in layout is improved, and the device can be further miniaturized.

According to the digital camera according to the twenty-first aspect, the in-vehicle confirmation camera in the twenty-second aspect, and the film-type camera in the twenty-third aspect, the digital camera, the in-vehicle confirmation camera, and the film-type camera having the above-described effects are provided. Each can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a main part of a digital camera according to a first embodiment of the present invention.

FIG. 2 is a diagram schematically illustrating an example of a configuration of a light receiving unit of the main image sensor illustrated in FIG.

FIG. 3 is a diagram showing an arrangement of pixel data created by a light receiving unit shown in FIG. 2;

FIG. 4 is a diagram schematically illustrating an example of a configuration of a light receiving unit of the sub-image pickup device illustrated in FIG.

FIG. 5 is a diagram showing an arrangement of pixel data created by the light receiving unit shown in FIG.

FIG. 6 is a flowchart illustrating a focusing process of the digital camera shown in FIG. 1;

FIG. 7 is a diagram illustrating waveforms based on image data of first and second subject images before correction in a normal state.

FIG. 8 is a diagram showing waveforms based on image data of first and second subject images after differential conversion in a normal state.

FIG. 9 is a diagram illustrating a waveform based on image data of a second subject image after correction in a normal state.

FIG. 10 is a diagram showing waveforms based on image data of first and second subject images before correction at the time of zooming.

11 is a diagram showing a waveform obtained by compressing image data of the first subject image shown in FIG.

12 is a diagram showing a waveform obtained by interpolating the image data of the second subject image shown in FIG.

13 is a diagram showing waveforms of image data of first and second subject images for explaining a correlation calculation process by the CPU shown in FIG. 1;

FIG. 14 is a schematic diagram illustrating an example of a positional relationship between a main imaging element and a sub imaging element in a normal state.

FIG. 15 is a schematic diagram illustrating an example of a positional relationship between a main image sensor and a sub image sensor during zooming.

FIG. 16 is a block diagram illustrating a configuration of a main part of a digital camera according to a second embodiment of the present invention.

FIG. 17 is a flowchart illustrating a focusing process of the digital camera shown in FIG. 16;

FIG. 18 is a diagram illustrating a waveform based on image data of a subject image in a state where light is not normally projected.

FIG. 19 is a diagram illustrating waveforms based on image data of a subject image and a reflected light image in a state where light is normally projected.

FIG. 20 is a diagram showing a waveform based on image data of a reflected light image in a normal state.

FIG. 21 is a diagram illustrating a waveform based on image data of only a reflected light image before and after zooming.

FIG. 22 is a diagram illustrating a waveform based on image data of only the reflected light image after correction.

FIG. 23 is a schematic diagram illustrating an example of a reference position on the main imaging element in a normal state.

FIG. 24 is a schematic diagram illustrating an example of a case where a subject moves in a normal state and a reflected light image of projected light moves on a main image sensor.

[Explanation of symbols]

 Reference Signs List 1 imaging optical system 2 main imaging element (imaging element) 3 sub-imaging optical system 4 sub-imaging element 5 lens driving section 6 main imaging element control section (imaging element control section) 7 sub-imaging element control section 8, 8a CPU 9 RAM 10 , 10a EEPROM 21 Projection optical system 22 Projection element 23 Projection element control section

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 7/30 G03B 19/02 2H054 7/32 H04N 5/232 H 3D020 7/36 J 5C022 G03B 13/36 G02B 7/11 N 15/00 A 19/02 B H04N 5/232 D G03B 3/00 A F-term (reference) 2F065 AA02 AA06 DD00 DD02 DD06 FF04 FF09 FF10 FF26 GG07 GG09 JJ02 JJ03 JJ05 JJ25 JJ14 LL06 Q22Q QQ24 QQ25 UU05 UU07 2F112 AA07 AA09 BA10 CA02 DA19 DA26 DA28 FA03 FA05 FA07 FA41 2H011 AA02 BA05 BA06 BA14 BA33 BB02 BB03 2H044 DA01 DA02 DA04 DC02 DE06 2H051 BA15 BA53 BA76 BB07 BB08 BB20 BB20 CB20 CB20 BB20 CB20 CB20 3D020 BA04 BC01 BD03 BE03 5C022 AA13 AB24 AB27 AB28 AC42 AC69

Claims (23)

[Claims] 1. A main imaging apparatus including a main optical system and an area image sensor for photographing a subject, and a sub optical system and a sub image sensor arranged at a position separated from the area image sensor by a predetermined base line length. A sub-imaging device that includes a sub-imaging device and adjusts the focus of the main imaging device based on the principle of triangulation using the outputs of the main imaging device and the sub-imaging device. A driving unit that drives the main optical system, a determining unit that determines a focus state by the area imaging device, and a correcting unit that corrects the main optical system according to a determination result of the determining unit. Characteristic ranging device. 2. The distance measuring apparatus according to claim 1, wherein said determining means makes a determination using an image output during driving of the main optical system by said driving means. 3. A main image pickup apparatus including a main optical system and an area image pickup element for photographing a subject, and a sub optical system and a sub image pickup element arranged at a position separated from the area image pickup element by a predetermined base line length. A sub-imaging device that includes a sub-imaging device, and adjusts the focus of the main imaging device according to the principle of triangulation using the outputs of the main imaging device and the sub-imaging device. A distance measuring device including a focus lens set at a predetermined position when performing distance measurement. 4. The distance measuring apparatus according to claim 3, wherein the predetermined position is an infinite position. 5. The distance measuring apparatus according to claim 3, wherein the predetermined position is a substantially intermediate position between an infinite position and a close position. 6. A main image pickup apparatus including a main optical system and an area image pickup element for photographing a subject, and a sub optical system and a sub image pickup element arranged at a position separated from the area image pickup element by a predetermined base line length. A sub-imaging device that includes a main imaging device and a sub-imaging device, and adjusts the focus of the main imaging device based on the principle of triangulation using the outputs of the main imaging device and the sub-imaging device. A storage unit for storing in advance information on a positional relationship between the subject and the main imaging device and the sub-imaging device, wherein triangulation is performed in accordance with the positional relationship information stored in the storage device. Characteristic ranging device. 7. The main optical system further includes a magnification changing mechanism, wherein the storage unit stores a plurality of pieces of information on the positional relationship at the time of zooming by the zooming mechanism, and the positional relationship at the time of zooming. 7. The distance measuring apparatus according to claim 6, wherein triangulation is performed according to the information of the distance. 8. A main imaging apparatus including a main optical system and an area image sensor for photographing a subject, and a sub optical system and a sub image sensor arranged at a position separated from the area image sensor by a predetermined base line length. A distance-measuring device having a sub-imaging device that includes a main imaging device and an output of the sub-imaging device. A distance measuring device comprising a correction unit for correcting an output difference from an output of a sub image sensor. 9. The apparatus according to claim 8, wherein the main optical system further includes a zoom mechanism, and wherein the correction unit corrects the output difference according to a zoom magnification of the zoom mechanism. Distance measuring device. 10. A main imaging apparatus including a main optical system and an area image sensor for photographing a subject, and a sub optical system and a sub image sensor arranged at a position separated from the area image sensor by a predetermined base line length. A sub-imaging device that includes a sub-imaging device, and adjusts the focus of the main imaging device based on the principle of triangulation using the outputs of the main imaging device and the sub-imaging device. And at least three filters having different spectral sensitivities required for color photographing, and the sub-imaging device is provided on each pixel so as to have a spectral transmission characteristic equivalent to the spectral transmission characteristic of the three filters. A distance measuring device comprising a filter. 11. A main image pickup device including a main optical system and an area image pickup device for photographing a subject, and a light projecting device arranged at a position separated from the area image pickup device by a predetermined base line length, In the distance measuring device for receiving the reflected light from the subject of the light projected by the light projecting device by the main imaging device and adjusting the focus of the main imaging device based on the principle of triangulation, the result of the triangulation is A driving unit that drives the main optical system according to the following: a determination unit that determines a focus state by the area imaging device; and a correction unit that corrects the main optical system according to a determination result of the determination unit. A distance measuring device characterized by the above-mentioned. 12. The distance measuring apparatus according to claim 11, wherein said determining means makes a determination using an image output during driving of the main optical system by said driving means. 13. A main image pickup device including a main optical system and an area image pickup device for photographing a subject, and a light projecting device arranged at a position separated from the area image pickup device by a predetermined base line length, In a distance measuring device that receives reflected light from a subject of light emitted by the light emitting device by the main imaging device and adjusts a focus of the main imaging device based on a principle of triangulation, the main optical system includes: A focus lens set at a predetermined position when performing the triangulation. 14. The distance measuring apparatus according to claim 13, wherein the predetermined position is an infinite position. 15. The distance measuring apparatus according to claim 13, wherein the predetermined position is a substantially intermediate position between an infinite position and a close position. 16. A main imaging device including a main optical system and an area image sensor for photographing a subject, and a light projecting device arranged at a position separated from the area image sensor by a predetermined base line length, In a distance measuring device that receives reflected light from a subject of light emitted by the light projecting device by the main imaging device and adjusts the focus of the main imaging device based on the principle of triangulation, a distance separated by a predetermined distance For a subject at a position, storage means is provided for storing in advance information on a positional relationship in which the main imaging device receives reflected light from the subject of light emitted by the light projection device, and is stored in the storage means. A distance measuring device for performing triangular distance measurement in accordance with positional relationship information. 17. The main optical system further includes a zoom mechanism, wherein the storage unit stores a plurality of pieces of information on the positional relationship at the time of zooming by the zoom mechanism, and the positional relationship at the time of zooming. 17. The distance measuring apparatus according to claim 16, wherein triangular distance measurement is performed in accordance with the information of: 18. The image forming apparatus according to claim 18, further comprising: a correction unit configured to correct a received light image of the main imaging device in accordance with a magnification ratio of the magnification mechanism. 18. The distance measuring apparatus according to claim 17, wherein a triangular distance is measured according to: 19. A main image pickup device including a main optical system and an area image pickup device for photographing a subject, and a light projecting device arranged at a position separated from the area image pickup device by a predetermined base line length, A distance measuring device that receives reflected light of a light emitted from the light projecting device from a subject by the main imaging device and adjusts the focus of the main imaging device based on the principle of triangulation. Storing an output distribution of the area image sensor before light, and forming a projected image by subtracting the stored output distribution from the output distribution of the area image sensor at the time of projecting light by the light projecting device. Distance measuring device characterized by the above-mentioned. 20. The light emitting device according to claim 11, wherein the light projecting device is disposed at an oblique position with respect to the main image pickup device.
20. The distance measuring apparatus according to any one of claims 19 to 19. 21. A digital camera comprising the distance measuring device according to claim 1. 22. An in-vehicle confirmation camera comprising the distance measuring device according to claim 1 on a vehicle body. 23. A film type camera comprising: the distance measuring device according to claim 1; and a monitor for displaying a captured image of the main image pickup device.