JPH0666966B2 - Stereoscopic focusing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to stereoscopic television imaging, and more particularly to a stereoscopic imaging focusing method in stereoscopic television imaging.

[Background of the Invention]

A conventional stereoscopic imaging camera is disclosed in Japanese Patent Laid-Open No. 56-106490.
As described in Japanese Patent Publication No. JP-A-2003-187, regarding the operation of the angle between the two cameras and the length of the base line, the zoom ratio is also taken into consideration, and the effect of stereoscopic vision is produced for the time being. However, the automatic focusing considering the convenience of the operator is not sufficiently considered, and the focusing characteristics are such that the lens optical axes of the two cameras intersect on the vertical bisector of the two cameras. It ’s only mediocre movements,
The full utilization of the stereoscopic imaging camera has not been considered.

That is, in the two-dimensional focusing operation, unlike the one-dimensional simple focusing of the lens, it is necessary to relate the inward movement of the two cameras, so-called converging movement, and the focusing of the lens. , It must be considered in close relation to the distance measuring method of the focusing device.

Further, focusing on the vertical bisector of the two cameras, that is, fixing the focus point, means that the user always looks only in the front direction in stereoscopic vision, which narrows the range of expression. There was a drawback.

[Object of the Invention]

An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and when performing stereoscopic imaging using two cameras, a stereoscopic imaging focusing method capable of obtaining focusing in accordance with the characteristics of a stereoscopic image to be captured. To provide.

[Outline of Invention]

In order to achieve this object, the present invention uses an infrared spot light to indicate the intersection of the two lens optical axes when stereoscopically capturing an object with two cameras, and the optical axis of the lens is set at the reflection point of the light. The feature is that the convergence movement is always performed by automatic tracking, and the distance is calculated based on the base line length between the two cameras and the two angles formed by them to focus (focus) the lens. There is.

This automatic tracking may be performed by the image pickup signals of two cameras.
It is also possible to perform focusing by moving the angle between the focus ring and the base line of the two cameras to a position where the correlation between the two image outputs is the highest under certain conditions.

With the above configuration, in the former case, no matter how the spot optical axis is moved, the vergence movement can be automatically performed. Also in the latter case, the same operation as the former can be performed only by determining the direction of the intersection of the focused optical axes instead of the spot optical axis. That is, by designating the direction of the locus of the intersection point of the lens optical axes, bringing the intersection point of the lens optical axis on that axis, and focusing on the intersection point, the higher correlation is obtained. Focusing is performed automatically by panning the two cameras in or out.

Example of Invention

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of a stereoscopic imaging focusing method according to the present invention, in which 1 is a spot light source, 2 and 3 are tracking devices for spot reflection points, 41 and 42 are angle detectors, Four
3 is a focus control device, 44 and 45 are lens driving devices, and 5
1, 52 are cameras, 53, 54 are lenses, 100 is a subject, (a) is the optical axis of light emitted from the spot light source 1,
(B) and (c) are optical axes indicating the center of tracking of the tracking devices 3 and 2, θ
₁ , θ ₂ and θ ₃ are angles formed by the baseline between the two cameras,
Although l is the base line length and the position of the spot light source is not limited, in this case, it is supposed to be the midpoint between the tracking device 2 and 3.

FIG. 2 is a schematic diagram for explaining the operation of FIG. 1, and the same reference numerals as those in FIG. 1 indicate the same parts, and the specific structures of the spot light source 1 and the tracking device 3 are also schematically shown. 11 is a condenser lens, 12 is a light emitting diode, 31 is a light receiving lens, and 32 and 33 are light receiving diodes.

Prior to explaining the operation of FIG. 1, the tracking device will be described first with reference to FIG.

In FIG. 2, optical axes (a) and (b) indicate the end of tracking, and the light-receiving diodes 32 and 33 are evenly illuminated.

Now, assuming that the tracking device 3 is initially oriented in the direction of (b '), light comes from the direction of (b), so the light receiving diode 3
More light is shining on 3. This is detected by a control circuit (not shown), the direction of the tracking device 3 is changed in the direction in which the angle θ increases, and the light receiving diodes 32 and 33 are stopped in a direction in which an equal amount of light strikes, whereby the automatic tracking is completed.

The above operations are performed by the automatic tracking devices 2 and 3 of FIG. 1, respectively, so that they face each other with respect to the spot light reflection point (a ′) of the subject 100.

On the other hand, an angle detector 41 composed of a potentiometer or the like,
Based on the detection signals θ ₁ and θ ₂ from 42 and the base line length l, the focus control device 43 calculates the distance L to the subject by the following equation (1), and the lens 53 is passed through the focus position lens drive devices 44 and 45. , 54 is moved to complete the focusing operation.

With the above operation, the spot light source 1 and the cameras 51, 52
It is possible to carry out automatic focusing of stereoscopic imaging with a pan head or the like on which is placed, and by shifting the angle θ ₃ from 90 °, the effect of shifting the line of sight can also be obtained, and more complete It is possible to obtain various stereoscopic images.

The above control operation will be slightly supplemented with reference to the flow chart shown in FIG. Now, when the tracking devices 2 and 3 start tracking, the angle output from the angle detectors 41 and 42 is changed to the focus control device 43.
Takes in. As a method of taking in this, for example, the angle detectors 41 and 42 are configured by potentiometers,
If those outputs are A / D-converted and input to the focus control device 43 composed of, for example, a microcomputer, the focus control device 43 can immediately detect the value. This is the step of incorporating θ ₁ and θ ₂ shown in the flowchart of FIG. L is calculated from the above-mentioned formula (1) from the taken-in θ ₁ and θ ₂ and l previously divided, and the lens position is input to the lens driving devices 44 and 45. The lens driving devices 44 and 45 include, for example, a lens position detection encoder, a drive motor, and a control circuit, and the control circuit controls the lens position detection encoder output and the lens position output from the focus control device 43 so that they match each other. It suffices to control the drive motor. Here, since it is not directly related to the essence of the present invention, its details are omitted.

As is apparent from the above, in the present embodiment, the cameras 51 and 52 track separately and only the focusing operation is performed by their movements. Therefore, the angle θ _{3 of the} spot light is Even if they are oriented at an angle, it is possible to automatically perform the convergence movement and the focusing movement.

FIG. 3 is a block diagram showing a second embodiment of the stereoscopic imaging focusing method according to the present invention, in which 41 and 42 are angle detectors and 46.
Is a control circuit, 31 is a camera driving device, ₁₂ is a base line length of the spot light source 1 and the tracking device 3, and the same reference numerals are given to the portions corresponding to FIG.

In the embodiment shown in FIG. 1, each of the two cameras individually tracks, but in this embodiment, only one tracking device 3 tracks the spot reflection point. At the same time as this operation, the control circuit 46 calculates the distance L to the subject and the angle θ _{1 of the} camera 51 based on the angles θ ₂ , θ ₃ and the base line length l ₂ , and according to the result, the lens drive circuit 44 is calculated. , 45 to automatically adjust the focus, and the camera driving device 31 to automatically adjust the angle of convergence. At this time, as described below, even during tracking, the focus and the angle θ change according to the changes in the angles θ ₂ and θ _{3.
Since 1} is continuously changed, a smooth focusing characteristic can be obtained.

The focusing operation of this embodiment will be described with reference to the flow chart shown in FIG.

Now, it is assumed that the tracking device 3 in FIG. 3 starts the automatic tracking and the angle detectors 41 and 42 detect the angles θ ₃ and θ ₂ .
This is the step of incorporating θ ₂ and θ ₃ shown in FIG. Similar to the focus control circuit 43 of the embodiment shown in FIG. 1, a control circuit 46 composed of an A / D converter, a microcomputer, etc., A / D-converts the values of θ ₂ and θ ₃ and fetches them. The distance L to the subject is calculated by the following equation (2) based on this and the previously divided distance l ₂ .

The lens position is taken out from this distance L and the lens driving device 4
4 and 45, and the focus of the cameras 51 and 52 is adjusted to the distance L by this value.

At the same time, using the previously divided distance l ₁ and the calculation result L, the angle θ ₁ is calculated by the following equation (3).

This angle θ ₁ is transmitted to the camera driving device 31, and the camera 5
By changing the direction of 3, a focusing operation is performed in which the distance L and the convergence angles θ ₁ and θ ₂ are combined, that is, the intersection of the optical axes (a) and (b) is adjusted to the focus and the camera angle. Can be made.

Calculation of L that the above operation is shown in FIG. 12, control the focus by the lens position output, the calculation of the theta _1, the angle theta ₁
This is a step of angle control of the camera 51 by output, and by circulating this step, it is possible to perform a smooth autofocus of the stereoscopic imaging device in accordance with the movement of the automatic tracking device 3.

Here, the focus position of the camera is the common distance L of the two cameras.
However, this is usually within the depth of field because the distance to the subject is long with respect to the base line length and there is not much difference between the distances from the cameras 51 and 52 to the subject. Because. However, in the case of a short-distance subject whose base line length is relatively short, the focus positions of the respective cameras must be adjusted separately. If the distances from the cameras 51 and 52 to the focal point at this time are L ₅₁ and L ₅₂ , respectively, in the first embodiment shown in FIG. Focus each camera to the distance.

On the other hand, in the second embodiment shown in FIG. The cameras 51 and 52 are respectively focused on the distances of.

In the above case, the focus control signals are separately output and input to the lens driving device, but they are not shown newly.

Instead of the distance L as described above, the distance L ₅₁ , L
_Although focus control may be performed using ₅₂ , it may take time to calculate, so it is detected that the distance L is not within the depth of field, and if it is within the depth, the distance L is calculated. If it is outside the depth, the distances L ₅₁ and L ₅₂ may be calculated to perform the focusing operation. However, since the distance L is usually sufficiently larger than the base line length l, the distance L alone is often sufficient. Needless to say, the above can be applied to the following embodiments.

Of course, the spot light may be emitted through the lens optical axis. This is shown in FIG. 4 as a third embodiment. In FIG. 1A, reference numeral 82 is a light receiving portion, and 83 is a camera driving device. A specific example of the light receiving unit 82 is shown in FIG. The direction of the camera 52 is adjusted so that the two light-receiving diodes 32 and 33 of the light-receiving section 82 are equally exposed to the light.
Change according to 3. This is exactly the same in principle of operation as the automatic tracking devices 2 and 3 described in the embodiment of FIG. By doing this, the angle θ ₂ is automatically tracked to the subject, and the optical axis
(D) The subject can be captured on top.

At the same time, due to the outputs of the detectors at the angles θ ₃ and θ ₂ ,
A control circuit (not shown) calculates the distance L and the angle θ ₁ of the other camera, and controls the focus and convergence angles in accordance with these values to perform autofocus during stereoscopic imaging.

FIG. 4 (c) is a block diagram showing a specific example of the lens 81 with a spot light source, in which 84 is a lens, 85 is a half mirror, and 86 is a light emitting element.

In the figure, the light from the light emitting element 86 is the half mirror 8.
5 to the lens 84. With such a configuration, the automatic focusing of the present invention can be easily realized.

In the embodiment described above, light emission and light reception are performed at approximately the midpoints of the two cameras, which is a more natural focusing method with less distinction between left and right. However, light emission and light reception are performed at other parts. May be taken.

FIG. 5 is a block diagram showing a fourth embodiment of the stereoscopic imaging focusing method according to the present invention, in which 2'is a tracking device, and the same reference numerals as those in FIG. 1 denote the same parts.

In this figure, in this embodiment, a tracking device 2'automatically performs tracking, and a control (not shown) is performed so that the intersection point and the focus of the two lenses are aligned on the line designated by the angle θ ₃ in the figure from the center of the base line. It is controlled by a circuit.

This operation will be described below with reference to the flow chart shown in FIG.

First, the angle theta ₃ inputted from the angle theta ₃ input device (not shown)
Is taken in by the control circuit by an A / D converter or the like. This step is illustrated by the incorporation of θ _{3 in} FIG. The angles θ ₁ and θ ₂ move while the angle of convergence is regulated by the relationship of the following expression (8) by the base line lengths l ₁ and l ₂ that have previously taken in this value.

To operate while defining this angle, first, the camera 5
The angle θ ₁ of ₁ is taken in by a detector (not shown), and the above equation is obtained by dividing l ₁ and l ₂ and the angle θ ₃ in advance.
Calculating a theta ₂ from (8), the angle of the driving device 83 the angle theta ₂
To match. At the same time, as already explained, for example the expression
The lenses 53, 81 of the cameras 51, 52 are brought into focus by the lens driving device (not shown) to the distance L calculated in (2). By doing so, the angle of focus and the angle of convergence are aligned with the intersection of the straight lines specified by the angles θ ₂ and θ ₃ . The above may of course define the angle θ ₁ by the angle θ ₃ and the angle θ ₂ , but it is essential that the angles θ ₁ and θ ₂ are regulated by the angle θ ₃ and therefore, in particular, there is no problem. Absent.

Now, now, the tracking device 2 'detector is, if it is detected that the object is a reflection point of the current distant from the focus position, i.e. Supotsuto light in a direction to increase as having a theta _1, the tracking device 2' Moves farther away. If the angle at this time is θ ₁ + Δθ ₁ ,
From equation (2), the distance is L + ΔL, and from equation (8), the angle θ
₂ is changed to θ ₂ + Δθ ₂ . By doing so, the tracking device 2'causes the camera 51 to reflect the spot light emitted from the lens 81 of the camera 52 on the object.
The autofocus operation for stereoscopic imaging can be performed.

FIG. 6 is a block diagram showing a fifth embodiment of the stereoscopic imaging focusing method according to the present invention, and the same reference numerals as those in FIGS. 1 and 5 denote the same parts.

In the figure, the spot light source 1 attached to the camera 52
The reflection point of is traced by the tracking device 2'attached to the other camera 51, and the operation is substantially the same as that of FIG. 5, so detailed description will be omitted.

FIG. 7 is a block diagram showing a sixth embodiment of the stereoscopic image pickup focusing method according to the present invention. In contrast to the fifth embodiment up to the fifth embodiment, the spot is focused on the reflection point. In the embodiment, the image signals of the two cameras are used, and the angle of convergence of the two cameras having the highest correlation between them is the focus position.

In the figure, 31 and 32 are camera driving devices, 33 is a correlation circuit, and 34 is a control circuit. Here, for the sake of simplicity, focusing is performed only on the vertical bisector of the base line length l. That is, it is assumed that θ ₁ = θ ₂ = θ. Also, 1
Reference numeral 01 denotes a subject, and the same reference numerals as those in FIG. 1 denote the same parts.

The operation of FIG. 7 will be described with reference to FIGS. 8 and 9.

8 and 9 are operation waveform diagrams of FIG. 7.
When θ decreases from 90 °, that is, when the camera is panned from a distant position to a close position, the subject 101
The image output for (1), (b), and (c) is made by the camera 51, and (a '), (b'), and (c ') are made by the camera 52. However, (c) and (c ') are waveforms at the time of focusing. 1H indicates one horizontal scanning period.

To explain one method of correlation, the output of the camera 51 is delayed by the delay amount ΔDL, and the product sum A with the output of the camera 52 is given.
The result is as shown in FIG. That is, (a),
In the case of (a ′), if (a) is delayed by + ΔDL, the waveforms overlap, and the sum of products A becomes large. When ΔDL indicating the peak point is +, the camera can be directed to the in-focus point by changing the distance to the closest point and when the ΔDL is −, changing to the direction of ∞ (infinity).

The above operation will be described with reference to the flowchart shown in FIG.

First, the operation start angle is θ. Next, the control circuit 34
After capturing the output of the correlation circuit 33,
That is, it is determined whether the output is + or very close, that is, whether the output is −. This is the step shown as the output in FIG. If the output is + due to the detection output,
When the angle θ is θ−Δθ, −, it is determined as θ + Δθ and output. This output is transmitted to the camera drive devices 31 and 32,
The angle θ is adjusted to the output value of the control circuit 34. On the other hand, the distance L to the subject from the angle θ is calculated by the following equation (9) and transmitted to the focus control devices 44 and 45 to perform focusing in parallel.

By changing the angles θ ₁ and θ ₂ of the camera and the focus position L of the lens, ΔDL of the correlation circuit 33 is almost 0.
If the focusing operation is stopped when the circuit output becomes 0, the autofocus operation for stereoscopic imaging is completed.
Of course, the strength of the correlation is low, that is, ΔD in this embodiment.
When the absolute value of L is large, if the change of the angle etc. is accelerated,
It goes without saying that the focusing operation is performed more smoothly.

In addition, in this embodiment, the configuration is for the case of θ ₁ = θ ₂ , but the present invention is not limited to this case. This will be described with reference to FIGS. 10 and 15.

FIG. 10 is a block diagram showing a seventh embodiment of the stereoscopic imaging focusing method according to the present invention, in which 63 is a θ ₃ input circuit, 61 is a control circuit, and the same reference numerals as those in FIG. 9 denote the same parts. Show.

FIG. 15 is a flow chart for explaining the embodiment of FIG.

In FIG. 10, first, the angle θ ₃ input circuit 63 is used to input the in-focus trajectory of stereoscopic imaging. In the figure, the line indicated by the distance L corresponds to the locus of the line. It is assumed that the angle θ ₁ is initially set.

At this time, θ ₂ is calculated and output from the equation (8) from the angles θ ₁ and θ ₃ and the base lines l ₁ and l ₂ . Camera drive 32
Controls the movement of the camera 52 to the angle θ ₂ by the same output.
Similarly, the distance L is calculated by, for example, the formula (2), and the cameras 51 and 52 are brought into focus. This is the default setting. Therefore, if the output of the correlation circuit 33 is now +, it is necessary to focus the camera in the close-up direction as described with reference to FIG. 9, and θ _{1 is set} to θ ₁ −Δθ ₁ and θ ₂ ( 8) and θ ₁ -Δθ ₁ is changed to a value θ ₂ -Δθ ₂ calculated using, L-[Delta] L is calculated by simultaneously distance L (2) below
Change to. By performing this operation until the output of the correlation circuit 33 becomes 0, the autofocus operation for stereoscopic imaging is completed. If there is a change in θ ₃ during this operation, the designated angle of the focus locus has changed.
It is necessary to detect this and return to the initial setting, for example. This is shown in the flow chart of FIG.

Here, the reason why there are more branches in the detection of θ ₃ than in the above flow chart is that when the output of the correlation circuit 33 becomes 0,
This is because the control method is such that the output of the correlation circuit 33 is continuously monitored until the change from 0 appears. Needless to say, the branching at the change in θ ₃ is unnecessary except this.

In the above embodiments, the case where the zoom ratio, that is, the focal length of the lens is not changed has been described. However, the essence of the present invention does not change even when the focal length changes.

By the way, as shown in the conventional example, in stereoscopic imaging, it has been proposed to change the baseline length by changing the zoom ratio. However, in the conventional example, the value is not limited, and it is sufficient if the focal length is low. However, when a lens with a high zoom and a high focal length is often used in recent years, the stereoscopic image shown in the conventional proposal is shown. Imaging is difficult to achieve. That is, when the zoom becomes a little high, the base line length becomes too wide to be practically used.

FIG. 16 is a constitutional view showing an eighth embodiment of the stereoscopic imaging focusing method according to the present invention, showing an embodiment of an autofocus system (focusing system) which actually corresponds to a change in zoom ratio,
Reference numerals 161 and 162 denote camera moving devices, 163 and 164 denote focal length control devices, and the other parts have the same reference numerals as those shown in FIG. Also, l ₁ , l
Reference numerals ₂ and 1 respectively represent the distance between the camera 51 and the spot light source 1, the spot light source 1 and the camera 52, and the distance between the camera 51 and the camera 52.

Regardless of the zoom ratio, if the value of the length l is input to the focus control circuit (not shown) by the detection means (not shown),
It is clear from the description of the operation of the first embodiment shown in FIG. 1 that the autofocus of stereoscopic imaging can be performed, and the description thereof will be omitted.

Now, it is assumed that the focal length f is changed by the focal length control devices 163 and 164 according to an input (not shown). It is the essence of this embodiment to control the change of the focal length and the distance l between the cameras 51 and 52 on a constant curve, and an example thereof is shown in FIG. FIG. 17 is a diagram for explaining the operation of FIG. 16, in which the horizontal axis represents the focal length f and the lenses 53,
54 also changes similarly. The vertical axis represents the distance 1 between the cameras 51 and 52, and the curve (h) shows the operation of the embodiment shown in FIG. When the focal length f is small, it is set so as to be almost proportional to the distance l, and the movement is controlled by the camera moving devices 161 and 162 so that the distance l reaches a peak as the focal length f becomes larger. By controlling so as not to increase at all, a practical stereoscopic imaging device can be configured.

The above is the same when l ₁ and l ₂ are different, and this is shown in FIG. 18. FIG. 18 is another operation explanatory view of FIG. 16, and when l ₁ and l ₂ are different, it is necessary to control so that l ₁ + l ₂ has a value of (h). The curves (ri) and (nu) in Figure 2 indicate this.

In this way, if the distances l ₁ and l ₂ are set, it is possible to provide a practical change in the base line length corresponding to the focal length f in the autofocus of stereoscopic imaging described above. This is simply the distance _l 1, _{l 2} is changed to correspond to the focal length f, to the distance _l 1, _{l 2} control circuit, for example, uptake by means of A / D conversion and the like, the angle theta _1,
Only θ ₂ and the distance L are calculated and controlled, and the operation thereof is clear, and thus the details will not be described.

In the above embodiments, the lenses are separately attached to the camera for explanation, but it goes without saying that a single lens can also be used. FIG. 19 shows an embodiment of this case.

FIG. 19 is a diagram showing a ninth embodiment of the stereoscopic imaging focusing method according to the present invention, which is 185, 186, 187, 188.
Is a mirror, 181, 182, 183, 184 are mirror angle changing devices, and 191, 192 are mirrors 185, 184.
Is a zoom lens, 193 is a focus control device, 194 is a focal length changing device, 195 and 196 are sensors, 197 and 198 are camera circuits, and 199 is a correlation circuit.

In the operation of this embodiment, the front focus and rear focus of the subject are detected by the output of the correlation circuit 199, and the focus control device 193 focuses in the direction of the distance L to the subject while the mirrors 185, 186, 187, 188 are used. By changing the angle of convergence, the autofocus of stereoscopic imaging is performed. Since this autofocus operation is exactly the same as the method of taking the correlation between the two images described above, the description thereof will be omitted.

Here, the main point of this embodiment is that, in the lens having such a structure, it is more difficult than the embodiment of FIG. 16 to make a large distance between the mirrors 185 and 187, and as shown in FIG. In addition, it is necessary to provide the fl characteristic, which is almost flat from the middle focal length.

In such a case, the range of the focal length where the fl characteristic is proportional is related to the stereoscopic imaging system and cannot be determined unconditionally. That is, the proper viewing angle when looking at the monitor depends on the number of scanning lines and the aspect ratio of the system. Further, depending on the light-receiving surface of the image pickup unit, for example, 1 inch and 1/2 inch have completely different view angles even with the same focal length.

However, the essence of the present invention is to determine the baseline so as to have a characteristic of having a straight line in the vicinity of the f-l value such that the appropriate viewing angle and the viewing angle of the image pickup section are substantially the same.

〔The invention's effect〕

As described above, according to the present invention, by tracking the intersection of the lens optical axes of the two cameras and focusing by the base line length between the two cameras and the angle formed by the two, the above-mentioned prior art is realized. It is possible to provide a stereoscopic imaging focusing method having an excellent function without the drawbacks.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of a stereoscopic imaging focusing method according to the present invention, FIG. 2 is a schematic diagram for explaining the operation of FIG. 1, and FIG. 3 is a stereoscopic imaging focusing according to the present invention. The block diagram which shows the 2nd Example of the focusing method, FIG. 4 (a), (b), (c) is a schematic diagram for demonstrating the 3rd Example of the stereoscopic imaging focusing method by this invention, 5, 6, and 7 are configuration diagrams showing fourth, fifth, and sixth embodiments of the stereoscopic imaging focusing method according to the present invention, respectively, and FIGS. 8 and 9 are diagrams of FIG. 10 is an operation waveform diagram for explaining the operation of the embodiment, FIG. 10 is a block diagram showing a seventh embodiment of the stereoscopic imaging focusing method according to the present invention, and FIGS. 11 to 15 are drawings for explaining each embodiment of the present invention. FIG. 16 is a configuration diagram showing an eighth embodiment of the stereoscopic imaging focusing method according to the present invention, FIGS. 17 and 18 are operation explanatory diagrams of the embodiment of FIG. 16, and FIG. 19 is a book. To invention Diagram showing a ninth embodiment of a stereoscopic imaging focusing how, FIG. 20 is a diagram for describing operation of the embodiment of Figure 19. 1 ... Spot light source, 2, 3 ... Spot reflection point tracking device, 41, 42 ... Angle detector, 43 ... Focus control device, 44, 45 ... Lens driving device, 51, 52 ...
Camera, 53, 54 ... Lens, 100 ... Subject.

Claims (3)

[Claims] 1. A focusing method for stereoscopic imaging using two cameras, wherein the position of the cameras is fixed, and a straight line connecting the cameras is used as a base line to perform stereoscopic imaging from a specific position on the base line. Set a desired direction, and perform the tracking operation to match the direction of each camera to the direction of the object located in the set direction, and use the information indicating the direction of the camera to determine the distance from the camera to the object. Is set, the position of the lens of each of the cameras is set according to the calculated value of the distance, and the subject of each of the cameras is verified as a stereoscopic imaging focusing method. 2. The means for setting the direction of the subject according to claim (1), wherein the means for setting the direction of the subject changes from a spot light source arranged at any position of the camera and the baseline to the subject. The means for irradiating light and performing the tracking operation is a light receiving means arranged at a position different from the spot light source on the camera and the base line to receive reflected light from the subject and To detect the light receiving direction, and match the optical axis direction of each of the cameras with the direction of the subject based on the light receiving direction of the reflected light detected by the light receiving means, to focus the camera on the subject. The means detects the tilt angle of the optical axis of the camera with respect to the base line set by the means for performing the tracking operation, calculates the distance to the subject using the tilt angle, and calculates the distance. Depending on the value of the distance, the camera sets the position of each of the lenses, stereoscopic imaging focusing process, characterized in that the camera respectively and so focuses on the subject. 3. The means for performing the tracking operation according to claim (1), wherein the output signal of one of the cameras is delayed by a variable delay amount, and the output signal of the other camera is delayed. A stereoscopic imaging focusing method characterized by changing the direction of the camera so that the delay amount is zero and the output signals are matched with each other as compared with the output signal.