JP3072996B2 - Camera zooming control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera zooming control device in which a camera sets zooming by setting a focal length of a taking lens.

B. Conventional technology Conventionally, there is known an electric zoom camera capable of so-called constant magnification photographing by operating a constant magnification setting button or the like to always photograph a subject at a constant size regardless of the subject distance. I have.

In this type of camera, a plurality of magnification tables in which the subject distance and the focal length are associated in advance are stored in the CPU in order to change the focal length of the photographing lens according to the subject distance and enable constant magnification photographing. I have. By operating the constant magnification setting button to set the constant magnification photographing mode and then half-pressing the release button, one of the magnification tables is selected in the camera, and the table of the table is selected. From inside
For example, a focal length corresponding to the subject distance obtained by the distance measuring circuit is selected and set, and the photographing lens is automatically driven to the focal length (electric zooming is performed). afterwards,
Shooting is performed by fully pressing the release button. In such a magnification table, the ratio between the subject distance and the focal length,
That is, the photographing magnification is always constant, for example, the upper body of the person or the whole person is always photographed in the same size, and the photographer can select the photographing magnification by operating the operation buttons and the like. I have.

Also, a camera in which a desired focal length is previously input to the camera by manual operation, and then a half-press operation of a release button is performed, whereby a photographing lens is driven at a stroke to the input focal length is also known. I have.

C. Problems to be Solved by the Invention However, in the camera capable of the constant magnification photographing, since the subject distance is required to select the focal length of the photographing lens from the magnification table as described above, the electric zooming is performed. The object distance (focus detection signal) is obtained by performing distance measurement before. After zooming, focusing of the photographing lens is performed based on the subject distance, and shutter release is performed in accordance with a full-press operation. That is, there is a time lag from the detection of the subject distance to the shutter release for the zooming. If the subject moves during the zooming, the shutter release as it is may result in a blurred photograph. Therefore, in order to prevent the out-of-focus state, it is necessary to release the half-press operation once and then perform the distance measurement and the zooming by half-pressing again.

Also, in a camera in which a desired focal length is previously input to the camera side by a manual operation and the photographing lens is driven at a stroke to the previously input desired focal length in response to a half-press operation of the release button, the zooming is also performed. If the distance measurement is performed before the above, there is the same problem as described above.

On the other hand, since the two types of cameras do not stop zooming until a predetermined focal length is reached when zooming is started, the two cameras change their mind before zooming ends and want to shoot at a different focal length. Zooming cannot be interrupted, and the only way to shoot at this different focal length is to release the constant magnification shooting mode and then operate the zoom button manually.

That is, the two types of cameras described above are not easy to use depending on the conditions.

An object of the present invention is to provide an easy-to-use camera zooming control device.

D. Means for Solving the Problems To be described with reference to FIG. 1 (a) which is a diagram corresponding to the claims, the invention of claim 1 is a focus detection which outputs a focus detection signal for focusing a photographic lens on a subject. Signal output means
101, focusing means 102 for driving the taking lens to the in-focus position based on the focus detection signal, and a half-pressing operation of the release operation member 103, so that the focal length previously set on the camera side is Zoom signal output means 104 for outputting a first zoom signal for guiding the photographic lens; and zooming means 105 for electrically driving the photographic lens to perform zooming in response to the first zoom signal. And the release operation member 103
This is applied to a zooming control device for a camera including a release means 106 for performing a shutter release in accordance with a full-press operation of the camera.

After the zooming by the zooming means 105 is completed, focusing is performed to drive the photographing lens to the in-focus position based on the focus detection signal between the time when the release operation member 103 is fully pressed and the time when the shutter is released. A control means 107 for operating the means 102 is provided to solve the above problem.

Also, referring to FIG. 1 (b) which is a claim correspondence diagram, the invention according to claim 2 is for guiding a photographing lens to a focal length according to a preset condition on a camera side in response to a predetermined command. A first zoom signal output means for outputting a first zoom signal; and a second zoom signal for arbitrarily changing the focal length of the taking lens by manual operation irrespective of the predetermined command. A second zoom signal output unit 202 for outputting a zoom signal, a zooming unit 203 for electrically driving the photographing lens in response to the first or second zoom signal to perform zooming, and a release unit 106 described above. Is applied to the zooming control device.

Then, when the second zoom signal is output while zooming is being performed in response to the first zoom signal, the first zoom signal is output.
While stopping the zooming according to the zoom signal of, the zooming is started according to the second zoom signal,
Thereafter, a control means 204 for inhibiting the operation of the first zoom signal output means 201 even when the predetermined command is output is provided, thereby solving the above-mentioned problem.

E. Operation (1) The invention according to claim 1 The control means 107 detects the focus after the zooming by the zooming means 105 is completed and before the shutter release is performed after the release operation member 103 is fully pressed. The photographing lens is driven to the in-focus position based on the signal.

(2) Invention of Claim 2 When the second zoom signal is output while zooming is being performed in response to the first zoom signal, the control means 204 stops the zooming, and outputs the second zoom signal. Zooming is started according to the zoom signal. That is, for example, a case in which constant-magnification shooting is performed in response to a half-press operation (predetermined command) will be described. Zooming is started in response to a half-press operation. When a button is operated, zooming is performed according to the operation. Then, even when the photographing lens is driven to a desired focal length by zooming with the zooming button and then half-pressed again, the operation of the first zoom signal output unit 201 is performed.
That is, since the zooming by the first zooming signal is prohibited, the photographing can be performed at a desired photographing magnification by performing the full-press operation subsequently.

F. Embodiment -First Embodiment- A first embodiment of the present invention will be described with reference to FIGS.

In FIG. 2 showing the overall configuration, a photometric circuit 2 and a distance measuring circuit 3 are connected to a CPU 1. The photometric circuit 2 is connected to a light receiving element 4 for receiving light from a subject.
Based on the detection signal of the light receiving element 4, luminance information (subject luminance) relating to the luminance of the subject is calculated and input to the CPU 1. The distance measuring circuit 3 is connected with a light projector 6 for emitting light toward the subject via a light projecting lens 5 and a light receiving element 8 for receiving reflected light from the subject via a light receiving lens 7.
Distance information (corresponding to a focus detection signal, hereinafter referred to as a subject distance) corresponding to the distance to the subject is calculated based on the detection signal of the light receiving element 8 and input to the CPU 1.

The CPU 1 also includes a motor drive circuit 11 for the focusing motor 9, the zooming motor 21 and the film winding / rewinding motor 10, an exposure control circuit 12 for driving and controlling the exposure control device 13, and a release button (not shown). ) Are connected to switches SW1 and SW2 which are turned on in conjunction with the pressing operation. The switch SW1 is turned on by half-pressing the release button, and the switch SW2 is turned on by full-pressing.

The CPU 1 turns on the switch SW1 to turn on the photometric circuit 2 described above.
And activates the distance measuring circuit 3 to calculate a lens driving amount for guiding a photographic lens (not shown) to a focusing position based on the object distance output from the distance measuring circuit 3, An exposure value is calculated based on the luminance. After that, when the switch SW2 is turned on, the motor drive circuit 1
The motor 9 is driven via 1 to move the photographing lens by the calculated lens moving amount to perform focusing. Thereafter, the exposure control member 13 is driven via the exposure control circuit 12 to perform photographing (shutter release), and the motor 10 winds up one frame of the film.

Further, switches SW3 to SW5 are connected to the CPU1.

The switch SW3 is a switch that is turned on in conjunction with the operation of a zoom-up button (not shown). The on-state of the switch SW3 is maintained while the zoom-up button is operated. While the switch SW3 is on, the CPU 1 outputs a second zoom signal, drives a zoom optical system (not shown) by the zoom motor 21 via the above-described motor drive circuit 11, and outputs the focal length of the photographing lens. To the telephoto side. That is, so-called zoom-up is performed.

The switch SW4 is a switch linked to a zoom-down button (not shown), and the on-state of the switch SW4 is maintained while the zoom-down button is operated. While the switch SW4 is on, the CPU 1 outputs a second zoom signal, drives the zoom optical system by the motor 21 via the motor drive circuit 11, and shifts the focal length of the taking lens to the wide-angle side. Change it. That is, so-called zoom-down is performed.

The switch SW5 is a momentary type switch that is turned on in conjunction with operation of a constant magnification shooting button (not shown).
U1 sets the constant magnification photographing mode by turning on the switch SW5. When the constant magnification photographing mode is set, so-called constant magnification photographing is performed in which the main subject is always photographed in a fixed size regardless of the distance to the subject.

That is, in the CPU 1, a plurality of focal lengths of the photographing lens corresponding to the subject distance are stored as magnification tables,
In these tables, the ratio of subject distance to focal length,
That is, the photographing magnification is fixed. The CPU 1 selects and sets one of the magnification tables according to the number of times the constant magnification photographing button is operated, that is, the number of times the switch SW5 is turned on.

In the camera according to the present embodiment, a magnification table A for photographing the subject from the neck upward at a constant magnification, a magnification table B for photographing the upper body of the subject at a constant magnification, and a photographing object And a magnification table C for photographing the whole body at a constant magnification. When the switch SW5 is turned on once in a state where the constant magnification photographing mode is not set, the above constant magnification photographing mode is set, and the magnification table A is selectively set.
When it is turned on once more, the magnification table B is selected and when it is turned on once more, the magnification table C is selected and set. When the switch SW1 is turned on by half-pressing operation after setting the magnification table, the CPU 1 automatically sets the focal length according to the subject distance obtained by the distance measuring circuit 3 from the selected magnification table, The first zoom signal is output to the motor drive circuit 11 for driving the photographing lens at this focal length. In addition,
When the switch SW5 is turned on while the magnification table C is selected, the constant magnification photographing mode is canceled.

When the switch SW3 or SW4 is turned on by operating the zoom-up button or the zoom-down button (collectively, the zooming button) after the setting of the constant magnification shooting mode, the CPU 1 cancels the constant magnification shooting mode. Then, a second zoom signal is output to the motor drive circuit 11 so that the motor 21 performs zoom-up and zoom-down. Even if the switch SW1 is turned on in this state, the automatic setting and driving of the focal length are not performed because the constant magnification shooting mode has been released. Thereafter, when the full-press switch SW2 is turned on and the above-described photographing operation is performed, the CPU 1 resets the constant-magnification photographing mode and resets the previously selected magnification table.

Next, the CP based on the flowcharts of FIGS.
The procedure of control by U1 will be described.

FIG. 3 shows a procedure for selecting a magnification table. When the switch SW5 is turned on, this program is started by interruption. First, in step S1, it is determined whether or not the magnification table A is currently set. If an affirmative determination is made, the magnification table B is set and the flag FLGB is set in step S6. If a negative determination is made, it is determined in step S2 whether the magnification table B is selected. When step S2 is affirmed, the magnification table C is set in step S7,
The flag FLGC is set, and if step S2 is denied, it is determined in step S3 whether the magnification table C is set. If step S3 is affirmed, the constant magnification photographing mode and the flag FLGC are released in step S8, and if negative, the constant magnification photographing mode is set in step S4, and then step
In step S5, the magnification table A is selected, and the flag FLGA is set. Thereafter, the flow returns to the normal processing. In the above processing, when any one of the flags FLGA, FLGB, FLGC is set, the other two are released.

Thereafter, when the switch SW3 or SW4 is turned on, the program shown in FIG. 4 is started by interruption, and first, in step S11, it is determined whether or not the constant magnification photographing mode is set. If a negative determination is made, the process proceeds to step S13. If an affirmative determination is made, the constant magnification shooting mode is canceled in step S12, and then the process proceeds to step S13. However, here, the flag FLG
A to C are not released. In step S13, it is determined whether the zoom-up switch SW3 is on. If the determination is affirmative, the motor 21 is transmitted via the motor drive circuit 11 in step S14.
As a result, the zoom-up process is performed, and the process returns to step S13.
If step S13 is denied, the process proceeds to step S15,
It is determined whether the zoom down switch SW4 is on. If step S15 is affirmed, the motor drive circuit is started at step S16.
The zoom-down process is performed by the motor 21 via the motor 11, and if step S15 is denied, the process returns to the normal process.

Fig. 5 shows the switch SW1 by half-pressing the release button.
2 shows a processing procedure when is turned on.

When the half-press switch SW1 is turned on, this program is started by interruption. First, in step S21, the distance measuring circuit 3 is turned on.
The object distance obtained by the above and the object luminance obtained by the photometric circuit 2 are read. Next, in step S22, a lens drive amount for guiding the taking lens to the in-focus position is calculated based on the subject distance, and an exposure value is calculated based on the subject brightness, and the process proceeds to step S23.

In step S23, it is determined whether or not the constant magnification photographing mode is set. If a negative determination is made, the process proceeds to step S24. If an affirmative determination is made, in step S41, a focal length corresponding to the subject distance read in step S21 is read with reference to the set magnification table, and a first zoom signal corresponding to the focal length is output. Then, the photographic lens is guided to the focal length selected by the motor 21 via the motor drive circuit 11.

Next, in step S21A, the distance measuring circuit 3 and the photometric circuit 2 are operated again, and the subject distance and the subject brightness at that time are read. In step S22A, a lens drive amount for guiding the taking lens to the in-focus position is calculated based on the subject distance obtained in step S21A, and an exposure value is calculated based on the subject brightness in step S24.
Proceed to.

In step S24, it is determined whether or not the full-press switch SW2 is on. If a negative determination is made, it is determined in step S25 whether or not the half-press switch SW1 is on. When step S25 is denied, the process returns to the normal process, and when affirmed, the process returns to step S24.

Here, when the switch SW3 or SW4 is turned on after the step S25 is denied and the process returns to the normal process, the above-described program of FIG. 4 is started by interruption, the constant magnification photographing mode is canceled, and the zoom-in or zoom-out operation is performed. Down processing is performed.

If step S24 is affirmed, the process proceeds to step S26, where step S22 (when the constant magnification photographing mode is not set) or step S22.
A focusing command signal corresponding to the lens driving amount calculated at 22A (when the constant magnification photographing mode is set) is output, and the photographing lens is driven to the in-focus position by the motor 9 via the motor driving circuit 11. Next, in Step S27, Step S
22 or an exposure control device 13 such as a shutter or an aperture through the exposure control circuit 12 based on the exposure value calculated in step S22A.
Is driven to perform shooting. Thereafter, in step S28, the film is wound one frame by the motor 10 via the motor drive circuit 11, and the process proceeds to step S29.

In step S29, it is determined whether or not the constant magnification photographing mode has been released. If a negative determination is made, the process returns to the normal process, and if a positive determination is made, the process proceeds to step S30. Step S30
Then, it is determined whether any of the flags FLGA, FLGB, and FLGC is set. If step S30 is denied, the process returns to the normal process. If affirmed, the constant magnification photographing mode is set again in step S31, and the process proceeds to step S32. In step S32, it is determined which of the flags FLGA, FLGB, and FLGC is set. If the flag FLGA is determined, the magnification table A is set in step S33. If the flag FLGB is determined, the magnification table A is determined in step S34. The table B is set, and if it is determined that the flag is FLGC, the magnification table C is set in step S35, and the process returns to the normal processing.

According to the procedure of FIG. 5 described above, when the half-press operation of the release button is performed while the constant magnification photographing mode is set,
A predetermined focal length is automatically set, and the photographing lens is driven to this focal length.
When the zoom up / down button is operated, the constant magnification photographing mode is released, and zoom up or zoom down processing is performed. Then, even if the half-press operation is performed again,
The automatic setting of the focal length and the driving of the taking lens are not performed. Therefore, if you do not like the composition based on the focal length set by the camera when you operate the constant magnification shooting button and then half-press, release the half-press and then operate the zoom up / down button to focus. Fine-tune the distance,
Thereafter, by performing a release operation, an image can be taken at a desired focal length.

Also, the constant magnification shooting mode released by operating the zoom up / down buttons is reset in conjunction with the end of shooting, and the previously set magnification table is reset similarly. It is not necessary to manually set the constant magnification photographing mode released by the manual operation of the zoom-up or zoom-down switch every time photographing is completed, so that the operability is improved.

Further, immediately after the zooming (step S41) is completed, the distance measurement is performed again, and a lens driving amount for guiding the photographing lens to the in-focus position is calculated based on the obtained subject distance, and the switch SW2 is turned on. Accordingly, focusing is performed based on the lens driving amount. As a result, the time lag from the distance measurement to the shutter release is shorter than in the case where focusing is performed based on the subject distance detected before zooming, so that the photograph is in focus even when the subject moves during zooming. Is more likely to be obtained.

In the above description, since photometry and exposure calculation are also performed after zooming, shooting can be performed with an appropriate exposure even if the subject brightness changes during zooming.

In the configuration of the above embodiment, the distance measuring circuit 3 is the focus detection signal output means 101, the motor drive circuit 11 and the focusing motor 9 are the focusing means 102, and the motor drive circuit 11 and the zooming motor 21 are the zooming means 10.
Exposure control circuit 12 constitutes release means 106, and CPU 1 constitutes zoom signal output means 104 and control means 107.

In the above description, the steps S21A and S22A are executed immediately after the completion of the zooming in the step S41. However, as shown in FIG. 6, for example, the steps S21A and S22A are executed in conjunction with turning on the switch SW2. You may. According to this, the time lag from the distance measurement to the shutter release is further reduced, and a focused photograph can be obtained with certainty.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIG. Note that the overall configuration is the same as that of FIG. 2 described in the first embodiment, and only the processing of the CPU 1 is different.

FIG. 7 is a modification of the zooming process in step S41 of FIG. That is, if step S23 in FIG. 5 is affirmed, the process proceeds to step S41A to start zooming to the focal length selected from the predetermined magnification table. Next, in step S41B, it is determined whether or not the zooming has been completed, that is, whether or not the photographing lens has been driven to the selected focal length. If the result is affirmative, the zooming is stopped in step S41E, and step S24 in FIG. Proceed to.

On the other hand, if step S41B is denied, the process proceeds to step S41C to determine whether one of the zooming switches SW3 and SW4 has been turned on. If step S41C is denied, the process proceeds to step S41F to determine whether or not the full-press switch SW2 is on. If it is off, the process returns to step S41B. If it is on, the zooming is stopped in step S41G and the process proceeds to step S26 in FIG.

If step S41C is affirmed, step S4
Stop zooming in 1D and step in Fig. 4 above
Proceed to S11.

According to the above procedure, when the release button is half-pressed (switch SW1 is turned on) when the constant magnification mode is set, zooming is started toward a predetermined focal length in the same manner as described above, and during this zooming, When the switch SW3 or SW4 is turned on by operating the zooming button, the above-mentioned zooming is stopped, and then the processing in FIG. 4 is performed. That is, the constant magnification shooting mode is canceled, and zooming is performed according to the operation of the switch SW3 or SW4. Therefore, after starting the zooming in step S41A, if you change your mind and want to shoot at another focal length before the set focal length is reached, you can operate the zooming button to set any focal length. The taking lens can be driven.
Then, the constant-magnification photographing mode is released by operating the zooming button, so that even if the camera is half-pressed after obtaining a desired focal length, zooming at the time of constant-magnification photographing is not performed, and photographing is performed at the desired focal length. be able to.

If the release button is fully pressed (switch SW2 is turned on) during zooming with the switch SW1 turned on, zooming is immediately stopped and step S26 (5th step) is performed.
(Figure) The following photographing process is performed. Therefore, step
If the desired focal length is obtained before the set focal length is reached after the zooming is started in S41A, the photographing can be performed at the focal length by fully pressing the release button.

In the configuration of the above embodiment, the CPU 1 controls the first zoom signal output means 201 and the control means 204, the switches SW3 and SW4 control the second zoom signal output means 202, and the motor drive circuit 11 and the zoom motor 21 control the zoom means. 203 respectively.

In the above description, a camera of a type that obtains a subject distance from reflected light of light projected on a subject and obtains a lens driving amount for guiding a shooting lens to a focus position based on the subject distance has been described. The present invention is not limited to this. For example, the present invention can be applied to a camera such as a single-lens reflex camera that obtains the above-mentioned lens drive amount from a shift amount and a shift direction between an imaging plane formed by a photographing lens and a predetermined imaging plane. In this case,
The subject distance may be obtained from the lens position after the caching.

In the above description, the case where the constant magnification is set has been described. However, the present invention is not limited to this. For example, a desired focal length is input to the camera in advance by manual operation, and the input focus is input by half-pressing the release button. The present invention can be similarly applied to a camera in which a taking lens is driven at a distance.

G. Effects of the Invention According to the invention of claim 1, after the completion of zooming, focus detection is performed between the time when the release operation member is fully pressed and the time when the shutter release is performed, and the focus detection signal is provided. , The time lag from focus detection to shutter release is almost constant and minimized, making it even more likely that a moving subject will be in focus. Become.

According to the second aspect of the present invention, zooming is performed in response to a predetermined command in accordance with a preset condition on the camera side, and is independent of the predetermined command during zooming according to the command. When the zooming operation is performed,
Since the zooming according to the above conditions is stopped and the zooming according to the zooming operation is started, and then the predetermined command is output, the zooming according to the command is prohibited. If you change your mind and want to shoot at a different focal length before reaching the focal length, operate the zooming button to drive the shooting lens to an arbitrary focal length and shoot at this focal length be able to.

In other words, according to the first and second aspects of the present invention, it is possible to provide a zooming camera that is more convenient than before.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims. 2 to 5 show a first embodiment of the present invention, FIG. 2 is a block diagram of a zooming control device for a camera according to the present invention, and FIGS. 3 to 5 show processing procedures. flowchart,
FIG. 6 is a flowchart showing a modification of the processing procedure. FIG. 7 is a flowchart of a processing procedure showing a second embodiment of the present invention. 1: CPU, 3: Distance measuring circuit 9: Focusing motor 11: Motor driving circuit 21: Zooming motor 101: Release operation member 102: First zoom signal output means 103: Second zoom signal output means 104 : Drive means, 105: Mode command means 106, 206, 306: Control means SW1 to SW5: Switch LE: Shooting lens

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Claims (2)

(57) [Claims] 1. A focus detection signal output means for outputting a focus detection signal for focusing a photographic lens on a subject; a focusing means for driving the photographic lens to a focus position based on the focus detection signal; A zoom signal output unit that outputs a first zoom signal for guiding the photographing lens to a preset focal length on the camera side in conjunction with a half-press operation of the operation member; and in response to the first zoom signal. A zooming control device for a camera, comprising: a zooming unit that electrically drives a photographing lens to perform zooming; and a release unit that performs shutter release in response to a full-press operation of the release operation member, after the zooming by the zooming unit is completed. Between the time when the release operation member is fully pressed and the time when the shutter release is performed, Camera zooming control device, characterized in that it comprises a control means for said taking lens on the basis of the point detection signal allowed to operate the focusing means to drive the focus position. 2. A first zoom signal output means for outputting a first zoom signal for guiding a photographing lens to a focal length according to a preset condition on a camera side in response to a predetermined command; A second zoom signal output means for outputting a second zoom signal for arbitrarily changing the focal length of the photographing lens by a manual operation irrespective of a predetermined command; and outputting the second zoom signal to the first or second zoom signal. A zooming control device for a camera, comprising: zooming means for electrically driving the photographing lens in response to perform zooming; and release means for performing shutter release in response to operation of a release operation member. Accordingly, when the second zoom signal is output while the zooming is being performed, the zooming according to the first zoom signal is stopped, and the zooming is stopped. A zooming control unit for starting zooming in response to the second zoom signal, and thereafter prohibiting the operation of the first zoom signal output unit even if the predetermined command is output. apparatus.