JPH08171048A - Camera - Google Patents

Abstract

PURPOSE: To provide a camera excellent in operability by rapidly switching the automatic and manual driving of a photographing lens. CONSTITUTION: This camera is provided with a controller 111 controlling an automatic focusing mode in which the photographing lenses L1 and L2 are moved in an optical axis direction by electric driving device based on the detected result by a focus detector 127 and a manual focusing mode in which the photographing lenses L1 and L2 are moved in the optical axis direction in accordance with operation by an external operating member 19, and it is provided with a detecting device 29 detecting the operation of the operating member 19 and an inhibition device 111 inhibiting the driving of the electric driving device in order to execute the manual focusing mode even in the automatic focusing mode in accordance with the detection by the detecting device 29.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to cameras, and more particularly to
The present invention relates to a camera suitable when a photographing lens that can be electrically driven and manually driven is used.

[0002]

2. Description of the Related Art As a photographing lens capable of moving an optical system by electric drive and manual drive, automatic focusing and manual focusing are possible by switching means as disclosed in Japanese Patent Laid-Open No. 55-73025. It is known to be configured to be selectively switched.

[0003]

In the camera using the conventional lens described above, some kind of switching operation is required to perform the manual focusing operation during the automatic focusing operation, so that the quick switching cannot be performed. The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a camera that can quickly switch between automatic and manual driving of a photographing optical system and has good operability.

[0004]

In order to solve the above problems, the camera according to claim 1 will be described with reference to FIG. 2 showing an embodiment.
Based on the focus detection device (127) that detects the in-focus state of the subject that has passed through 2) and the detection result of the focus detection device (127), the imaging lens (L1, L2) is driven by the electric drive device (113). And a control device for controlling an autofocus mode for moving the lens in the optical axis direction and a manual focus mode for moving the taking lenses (L1, L2) in the optical axis direction according to the operation of the external operation member (19). 11
A camera equipped with 1), comprising a detection device (29) for detecting an operation of an external operation member (19), and a detection device (29).
In response to the detection of the, the prohibiting device (11) for prohibiting the driving of the electric driving device (113) in order to execute the manual focus mode even in the autofocus mode.
1) and are provided.

According to a second aspect of the present invention, there is provided a detection device (2
9) detects that the external operating member (19) has been operated when the electric signal generated by operating the external operating member (19) has detected a predetermined number of times or more within a predetermined time. In the camera according to claim 3, the detection device (29) detects the operation of the external operation member (19) by detecting the electric signal generated by the photo interrupter (53).

According to a fourth aspect of the present invention, there is provided a photographing lens (L
1, L2) and a focus detection device (127) that detects the focus state of the subject, and based on the detection results of the focus detection device (127), an electric drive device (113) causes the taking lens (L1, A control device for controlling an autofocus mode for moving L2) in the optical axis direction and a manual focus mode for moving the taking lenses (L1, L2) in the optical axis direction according to an operation of an external operation member (19). (111) and a first detection device (29) for detecting an operation of the external operation member (19), and in the autofocus mode in response to the detection of the first detection device (29). In order to execute the manual focus mode, a prohibiting device (111) for prohibiting driving of the electric driving device (113) and a second detecting end of operation of the external operating member (19) In response to the detection of the output device (29) and the second detection device (29), the permission device (111) that permits the drive of the electric drive device (113) in order to return from the manual focus mode to the auto focus mode. ) And.

[0007]

When the operation of the external operating member (19) is detected, the prohibiting device (111) prohibits the driving of the electric drive device (113). Therefore, in the cameras according to the first to third aspects, the manual focus mode can be promptly executed even in the auto focus mode.

In the camera according to claim 4, when the operation of the external operating member (19) is detected, the prohibiting device (111) prohibits the driving of the electric drive device (113), and the external operating member (19). ) Is detected, the permission device (111) permits the drive of the electric drive device (113). Therefore, in the camera according to the fourth aspect, the autofocus mode can be promptly executed after the interruption operation of the manual focus mode is completed.

[0009]

1 to 3 show an embodiment of the present invention, and an embodiment applied to a lens barrel for automatic focusing capable of automatic focusing and manual focusing will be described below with reference to the drawings. . The lens barrel of FIG. 1 can be attached to the camera B having the automatic focus detection device shown in FIG. 2, and during the automatic focusing shooting, the driving force of the automatic focusing motor 113 on the camera side causes the shooting optical system L1. L
2 is configured to be driven.

In FIG. 1, a fixed barrel 11 having a bayonet claw 11a for mounting on the camera body is an inner barrel portion 11.
A straight advancing cylinder 15 for holding the photographing optical systems L1 and L2 is fitted to the inner circumference of the inner cylinder 11d. Further, a cam cylinder 13 having an external gear 13a which constitutes a part of a differential gear mechanism, which will be described in detail later, is rotatably fitted to the outer periphery of the inner cylinder portion 11d.

A cam groove 13b provided in the cam barrel 13
In the fixed cylinder 1, a sliding pin 47 planted in the straight-moving cylinder 15 is attached.
The linear guide groove 11c, which is long in the optical axis direction and is provided in the inner cylindrical portion 11d of No. 1, penetrates and is engaged. As a result, the cam barrel 1
By the rotation of 3, the rectilinear barrel 15 moves along the optical axis together with the optical systems L1 and L2. A distance scale cylinder 60 is fixedly provided on the front end of the cam barrel 13, and the distance scale printed on the outer peripheral surface 60a of the cam barrel 13 can be read through a distance display window provided on the front fixed barrel 21. Has been done. In the conventional photographing lens, the set distance scale is generally provided on the manual operation member, but in the case of the embodiment, there is no correlation between the position of the manual operation member 19a and the positions of the optical systems L1 and L2. Therefore, the manual operation member 19a cannot be provided with a distance scale. Therefore, in the embodiment, the distance scale 60 is fixedly provided at the tip of the cam barrel 13 that rotates in correlation with the movements of the optical systems L1 and L2, and the distance scale is printed on the outer circumference 60a of the cam barrel 13 and provided on the front fixed barrel 21. The distance is read from the scale window 21a.

The tip of the outer cylinder portion 11e of the fixed cylinder 11 (see FIG. 1)
A manual rotary cylinder 19 is fitted and supported at the middle left end).
The manual operation ring 19 includes an operation unit 19a that is externally operated, and a rotary barrel 19b that is interlocked with another barrel inside the barrel. Since the pin 27 that engages with the circumferential groove 11b formed in the outer tubular portion 11e of the fixed barrel 11 is planted in the rotary barrel 19b, the manual rotary barrel 19 is guided by the circumferential groove 11b and the pin 27. , Is fitted and supported by the outer cylindrical portion 11e so as to be rotatable only. An anti-slip rubber ring 25 is attached to the outer periphery of the operating portion 19a, and the rotary cylinder 19b is attached.
A planetary gear 41, which constitutes a part of a differential gear mechanism to be described later, is supported by a shaft 43 at the rear end.

A first internal gear 17a meshing with the planetary gear 41 and a coupling shaft 37 which is rotated by a motor driving force (driving force of the motor 113 in FIG. 2) are provided on the inner circumference of the outer cylindrical portion 11e of the fixed cylinder 11. Pinion gear 37 formed at one end
An internal gear cylinder 17 integrally provided with a second internal gear 17b meshing with b is rotatably supported. The wave washer spring 49 for friction braking is sandwiched between the manual rotary cylinder 19 and the front fixed cylinder 21 fixed to the fixed cylinder 11, and a predetermined torque is applied to the manual rotary cylinder 19 by its frictional force. There is.

The front fixed cylinder 21 is fixed with a photo interrupter 53 and a flexible printed circuit board 55 (hereinafter referred to as an encoder 55) long in the circumferential direction in which an encoder pattern is formed. The photo interrupter 53 has a cylindrical code plate 51 (a light transmitting portion provided in a circumferential direction at a constant interval) fixed between the light emitting portion and the light receiving portion at the tip of the rotary cylinder 19b of the manual rotary cylinder 19. The pulse signal corresponding to the rotation of the manual rotary cylinder 19 is transmitted to the in-lens CPU 29 by moving the manual rotation cylinder 19 along with the rotation of the manual rotary cylinder 19.

Further, in the encoder 55, a code corresponding to the position of the sliding brush 57, that is, the angular position of the cam cylinder 13 is generated by the sliding brush 57 fixed to the tip of the cam cylinder 13 sliding on the surface thereof. A conductor pattern is formed so as to be output. That is, a signal indicating whether the optical systems L1 and L2 are located at the infinite position, the closest position, or another position is transmitted to the in-lens CPU 29.

The in-lens CPU 29 is connected to the lens mount contact pin 31 via a leaf spring 33, and the contact pin 31 and the leaf spring 33 are held in the mount inner diameter portion by a contact housing 35. The clamp screw 45 screwed into the fixed barrel 11 is configured to press the outer periphery of the internal gear barrel 17 and prevent the rotation of the internal gear barrel 17 by being screwed.

FIG. 2 is a schematic diagram schematically showing the system configuration in which the lens barrel A of this embodiment is attached to the camera body B. The same parts as those in FIG. 1 are designated by the same reference numerals. In FIG. 2, when the taking lens A is mounted on the lens mount 141 on the camera body B side via the bayonet claws 11 a provided on the fixed barrel 11, the lens side coupling shaft 37 becomes the camera body side coupling shaft 1.
Combine with 25. The coupling shaft 125 is rotationally driven by a motor 113 controlled by a drive signal from a CPU (arithmetic processing unit) 111 in the body via a friction clutch 115 and reduction gear trains 121 and 123.

The light from the subject that has passed through the photographing optical systems L1 and L2 is partially reflected by the movable mirror 129 and is reflected by the focusing screen 1.
A subject image is formed on 33. The subject image is observed through the condenser lens 134, the pentaprism 135, and the viewfinder eyepiece lens 136. Part of the light transmitted through the semi-transparent mirror portion provided in the central portion of the movable mirror 129 is reflected by the sub mirror 131, and a pair of light receiving devices (pupil division type automatic focus detection device) 12 including an imaging lens are provided.
An image is formed on the light receiving surface of 7. The signal photoelectrically converted by the light receiving device 127 is sent to the in-body CPU 111, and the defocus amount (image plane deviation amount and direction from the planned focal plane) is obtained according to the image formation state.

The CPU 111 in the body is connected to the lens contact 3
In-lens CP via 3, 31 and body side contact 139
It is electrically connected to the U 29 and various information regarding the lens can be read from the ROM inside the CPU 29 in the lens. Therefore, the information indicating the image plane movement amount per coupling unit rotation amount is read out, and the motor drive amount necessary for focusing is obtained from the defocus amount described above. When the motor drive is started, a pulse signal corresponding to the motor shaft rotation amount is generated by the code plate 119 and the photointerrupter 117 provided on the motor shaft, so a pulse corresponding to the required motor rotation amount is generated. At this point, the motor drive is stopped and the subject is focused.

When the lens-side drive shaft 37 is rotated by the drive of the motor 113 which is controlled according to the image forming state of the photographing optical systems L1 and L2, the pinion gear 3 integrated with the drive shaft 37 is formed.
7b rotates. The rotation of the pinion gear 37b is transmitted to the internal gear cylinder 17 via the second internal gear 17b of the internal gear cylinder 17, and the first internal gear 17a rotates about the optical axis.
The rotation of the first internal gear 17a causes the planetary gear 41 to rotate. In the case of only the automatic focusing, the rotation of the shaft 43 supporting the planetary gear 41 and the manual rotary cylinder 19 is suppressed by the frictional force of the friction braking spring 49. Therefore, the rotation of the planetary gear 41 causes the external gear meshed with the external gear. The cam cylinder 13 having 13a rotates.

Therefore, the rotational torque T1 of the manual rotary cylinder 19
And the rotational torque T2 of the cam barrel 13 must be set to satisfy the relationship of T1> T2. FIG. 3 is a sectional view taken along the line III-III in FIG. 1, which is a main part of the differential gear mechanism. First, the operation of the differential gear mechanism during the automatic focusing operation will be described. In the case of automatic focusing from a long distance to a short distance, the cam cylinder 13 rotates clockwise with the external gear 13a by the counterclockwise rotation of the internal gear cylinder 17 in FIG. The rotation of the cam barrel 13 causes the sliding pin 47 to be engaged with the cam groove 13b to be moved leftward in FIG. 1 by being guided by the rectilinear guide groove 11c, and to move the rectilinear barrel 15 and the photographing optical systems L1 and L2 to the left. Displace toward. As a result, focus adjustment is automatically performed from infinity to a close range. On the contrary, in the case of automatic focusing from a close distance to a long distance, the internal gear 17a rotates clockwise in FIG. 3 by the reverse rotation of the pinion gear 37b, and the external gear 13a
At the same time, the cam barrel 13 rotates counterclockwise. As a result, the rectilinear barrel 15 and the photographing optical systems L1 and L2 move to the right, and automatic focusing on a long distance is performed.

Next, the operation of the differential gear mechanism when the manual focusing operation is performed during the automatic focusing operation will be described. When a manual focusing operation is performed in the middle of the automatic focusing operation by the motor drive, the rotation of the internal gear cylinder 17 and the rotation of the planetary gear 41 by the motor drive, and the planetary gear 41 by the manual focusing operation.
And the revolution are combined to rotate the cam cylinder 13 (that is, the drive amount combining means). The drive amount synthesizing means is configured as a cam cylinder 1 driven by a motor.
There are a case where the driving of No. 3 and the driving of the cam cylinder 13 by the manual operation are simultaneously operated and combined, and a case where only one of them is selectively operated.

In the manual focusing operation, when the manual rotary cylinder 19 rotates, the planetary gear 41 also revolves around the optical axis 43 while revolving around the optical axis, and the amount corresponding to the operation amount of the manual rotary cylinder 19. Only the cam barrel 13 is rotated to take the photographing optical system L.
Move 1 and L2. The operation of this embodiment will be described in detail below. First, during the automatic focusing operation, the taking lens L
Consider the case where 1 and L2 reach the limit end at infinity or the closest position. In the case of an automatic focusing lens barrel that does not have a general differential gear mechanism, when the photographing optical system reaches the limit end at infinity or the close-up position, it is limited by the limit end, so the drive shaft of the motor stops. The output pulse of the photo interrupter 117 in FIG. 2 is not generated, and it can be detected that the photographing optical system has reached the limit end. But,
In the case of the lens barrel having the differential mechanism as in the embodiment, when the limit of infinity or the near limit is reached and the rotation of the cam barrel 13 is restricted by the limiting end, the internal gear barrel 1 by the driving force of the motor 113 is generated.
The rotation of 7 revolves the planetary gear 41 and the manual rotary cylinder 19 rotates accordingly, so that the drive shaft of the motor 113 does not stop and it is not possible to detect that the limit end of the optical system has been reached.

Therefore, in the embodiment, an encoder 55 for detecting the rotational angle position of the cam barrel 13 is provided, and the encoder 55
In this way, the limit end of the photographing optical system at the infinity or the near position is electrically detected. That is, when the limit is reached, a code signal indicating that the limit is reached is sent from the encoder 55 to the in-lens CPU 29. Then, a signal indicating that the photographing lens has reached the limit end is sent from the in-lens CPU 29 to the in-body CPU 111, and the control circuit of the in-body CPU 111 performs control for reversing or stopping the operation of the drive motor 113. .

Next, consider a case where a manual focusing operation is performed during automatic focusing drive of the photographing optical system. A case will be described in which the drive amount synthesizing unit described above selects one of the drive by the automatic focusing operation and the drive by the manual focusing operation. For example, when the contrast of the subject becomes low during the automatic focusing operation, or when the subject suddenly moves and the defocus amount increases, the defocus amount may not be obtained even if focus detection is performed. . In such a case, it is necessary to manually perform the focusing operation. Therefore, the manual focusing operation is performed during the automatic focusing drive in the state where the defocus amount is not obtained. During the manual operation, the drive motor 113 is irrelevant to the intention of the photographer (for example, the automatic focusing operation is performed). If it responds, it will not be possible to perform manual operation as expected, which is inconvenient.

If a manual focusing operation is performed during the automatic focusing drive in the state where the defocus amount is obtained, the photographing optical system L
Since the actual movement amount of L1 and L2 is a combined amount of the motor drive amount and the manual operation drive amount, the pulse number of the photo interrupter 117 and the movement amount of the taking lenses L1 and L2, that is, the image plane movement amount are described. The relationship with (the amount of movement on the focus surface) is lost, and accurate focusing becomes impossible. So, in the example,
The photo interrupter 53 detects that the manual rotary cylinder 19 has been operated, and when it is operated, the automatic focusing drive of the photographing lens is stopped.

That is, when the manual rotary cylinder 19 is operated,
A pulse signal is transmitted from the photo interrupter 53 to the CPU 29 in the lens according to the rotation. CP in this lens
In U29, the photo interrupter 53 is within a fixed time Δt,
When a pulse of a constant number Δn or more is generated, it is determined that the manual focusing operation is being performed, and a signal for stopping the motor drive (hereinafter, referred to as a servo prohibition flag) is transmitted to the in-body CPU 111. This time Δt and the number of pulses Δn
If the value is extremely small, the motor 113 will stop even with a slight movement of the manual rotation barrel 19, so it is absolutely necessary to avoid touching the manual operation ring 19 with the hand when holding the lens barrel. Therefore, the holding property of the lens barrel is deteriorated. Further, if the value is extremely large, accurate focusing cannot be performed as described above, so that the value needs to be an appropriate size.

As described above, when the manual focus operation is performed during the automatic focus drive, the servo prohibit flag is continuously output while the manual operation ring 19 is rotating, that is, while the manual operation ring 19 is being manually operated. The drive of the drive motor 113 is stopped. When the manual focusing operation is completed and the rotation of the manual operating ring 19 is stopped, the servo prohibit flag is switched so as not to be output, and the automatic focusing operation by the motor drive is restarted. However, the motor drive is started at the same time when the rotation of the manual operation ring 19 is stopped.
Then, the movement of the manual operation ring 19 cannot be stopped even for a moment during the manual operation. Therefore, the timing of stopping the output of the servo prohibition flag is Δt ′ after the rotation of the manual operation ring 19 is stopped. You need to set it later. The value of Δt ′ may be fixed to a fixed value, but the optimum value of Δt ′ is taken according to the type of lens, size, and photographing conditions. Therefore, the value of Δt ′ may be arbitrarily changed by the photographer using the changeover switch. Further, the body side CPU 111 may be configured to restart the motor drive after a fixed time Δt ′ from the time when the servo prohibit flag from the lens is not present.

When the automatic focusing lens barrel of the embodiment is attached to a camera body which is not for automatic focusing or when it is attached to a camera body for automatic focusing shown in FIG.
When 5 is retracted (manual focusing mode is selected), the lens side coupling shaft 37 is free.
When the manual operation ring 19 is rotated for the manual focusing operation in this state, the internal gear cylinder 17 is rotated more than the rotation torque of the cam cylinder 13.
Since the rotational torque of the optical system L1, the internal gear cylinder 17 only rotates, the cam cylinder 13 does not rotate.
L2 does not move and manual focus operation is not possible.

Therefore, in the embodiment, at the time of the manual focusing operation, the clamp screw 45 is screwed in to limit the rotation of the gear cylinder 17, thereby enabling the manual operation. It is also possible to provide a switch interlocking with the screwing of the clamp screw 45 and, when clamped, send a signal from the lens to the body to indicate that manual operation is in progress. Above, FIGS.
Although the embodiment has been described based on the above, the present invention is not limited to this embodiment. For example, the distance scale display is performed by providing the distance scale cylinder 60 interlocked with the cam cylinder 13, but by increasing the number of positions that can be detected by the encoder 55, the output code of the encoder 55 causes
The rotational position of the cam barrel 13, that is, the shooting distance can be known. Therefore, it is possible to display the value on the lens side or the body side using a liquid crystal display element or the like.

In the above-described embodiment, the detection of the limiting ends of the photographing optical systems L1 and L2 during the automatic focusing drive is performed by the brush 57 and the encoder 55 provided on the cam barrel 13, but it is not always necessary to do so. For example, when it is possible to allow the manual operation ring 19 to rotate a minute amount when the photographing optical systems L1 and L2 reach the limit end during the automatic focusing drive, the limit end is detected by using the output pulse of the photo interrupter 53. But it is possible.

That is, when the cam cylinder 13 comes into contact with a mechanical limit and its rotation is restricted, the manual operation ring 19 starts to rotate when the drive motor 113 continues to rotate. If the rotation is detected, it is possible to stop driving the motor 113, knowing that the limit end has been reached. In the above embodiment, the problem in the case where the drive amount synthesizing means synthesizes the drive by the automatic focusing operation and the drive by the manual focusing operation is described, and an alternative example (manual operation ring 19) The drive of the motor 113 is stopped when is operated. However, it is not always necessary to stop the motor drive even if the respective drives are combined. For example,
When the manual operation ring 19 is manually operated, the operation amount and direction are electrically detected, and the number of output pulses of the photo interrupter 53 in the body is corrected based on the operation amount, so that the photographing optical system L1, If the correlation between the amount of movement of L2 and the output pulse of the photo interrupter 53 in the body can be maintained, accurate automatic focusing drive can be achieved without stopping the motor drive during manual operation.

In the embodiment of the present invention, the example of the interchangeable automatic focusing lens barrel which can be mounted on the camera body for automatic focusing has been described, but the present invention is not limited to this, and for example, a lens mirror. The present invention is also applied to a mechanism such as a lens barrel for automatic focusing having a driving motor for a photographing optical system in a cylinder, a power focus (a focusing device driven by a motor), a power zoom (a zooming device driven by a motor), and the like. Is applicable.

[0034]

As described above, according to the present invention, since the motor drive is stopped when the external operating member is operated by the photographer, the moving optical system moves only by manual operation.
Therefore, the feel of manual operation is good (for example, the relationship between the amount of manual operation and the amount of movement of the image plane is constant), and switching between manual operation and motor drive is possible without any special switching operation. Can be greatly improved.

Further, according to the embodiment, when the automatic focusing is impossible or the automatic focusing is uncertain, the manual operation ring is simply operated even during the automatic focusing drive (that is, as in the conventional camera system). , It can be quickly operated near the in-focus point by the manual focusing operation (without operating the switch for switching between the automatic focusing mode and the manual focusing mode), and the automatic focusing is automatically performed if the operation of the manual operation ring is stopped. Since it is possible to return to the drive and automatically drive to the in-focus point, it is possible to similarly perform a quick focusing operation.

[Brief description of drawings]

FIG. 1 is a drawing showing a sectional view of a lens barrel capable of automatic focusing and manual focusing with a differential gear mechanism according to an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic diagram of a system configuration when the lens barrel is attached to a camera body for automatic focusing.

FIG. 3 is a drawing showing a cross-sectional view taken along the line III-III of FIG.

[Explanation of symbols]

 13, 41, 17 ... Differential gear mechanism 55, 57 ... Moving end detecting means 19 ... Manual operation ring 51 ... Code plate (manual operation detecting means) 53 ... Photo interrupter (manual operation detecting means) 45 ... … Clamp screw 49 …… Wave washer spring for friction braking

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G03B 13/34 G03B 3/10

Claims (4)

[Claims] 1. A focus detection device for detecting a focus state of an object that has passed through a photographing lens, and an electric drive device for moving the photographing lens in an optical axis direction based on a detection result of the focus detection device. A camera provided with an autofocus mode and a control device for controlling a manual focus mode for moving the taking lens in the optical axis direction according to an operation of an external operation member, detects an operation of the external operation member. A detection device; and a prohibition device that prohibits driving of the electric drive device in order to execute the manual focus mode even in the autofocus mode in response to detection by the detection device. Camera 2. The camera according to claim 1, wherein the detection device operates the external operation member when an electric signal generated by operating the external operation member is detected a predetermined number of times or more within a predetermined time. A photographic lens characterized by detecting. 3. The camera according to claim 2, wherein the detection device detects an operation of the external operation member by detecting an electric signal generated by a photo interrupter. 4. A focus detection device for detecting a focus state of a subject that has passed through the photographing lens, and an electric drive device for moving the photographing lens in the optical axis direction based on a detection result of the focus detection device. A camera provided with an autofocus mode and a control device for controlling a manual focus mode for moving the taking lens in the optical axis direction according to an operation of an external operation member, detects an operation of the external operation member. A first detection device; a prohibition device that prohibits driving of the electric drive device to execute the manual focus mode even in the autofocus mode in response to detection by the first detection device; A second detection device for detecting the end of the operation of the operation member, and whether the manual focus mode is set in accordance with the detection by the second detection device. Wherein in order to return to the auto focus mode, the camera, characterized in that and a permission unit for permitting the driving of the electric drive.