JP6256501B2 - Vibration correction camera, correction lens and camera system - Google Patents

Description

  The present invention relates to a shake correction camera having a shake correction function for preventing shake, or a shake correction camera by combining a shake correction lens barrel having a shake correction function and a camera body mounted on the shake correction lens barrel. It is about the system.

  Conventionally, in this kind of shake correction camera and shake correction camera system, in order to prevent shake of the image on the imaging surface, film surface, or viewfinder, the angular velocity due to camera shake generated in the camera or lens barrel is reduced. In a video movie or the like, an image shake amount is detected from an image, and a part of a photographing lens as a shake correction optical system (hereinafter referred to as a correction lens) is detected according to the detected shake amount. Shifting in two directions (one of which is the yawing direction and the other is the pitching direction) perpendicular to the photographing optical axis and perpendicular to each other, in the imaging surface, film surface, or viewfinder One that corrects image blur is known. The following methods are known as the shift mechanism configuration of the correction lens. According to Japanese Patent Laid-Open No. 9-80520, the correction lens has four elastically bendable support rods arranged in parallel to the optical axis and attached to the fixing member of the lens barrel. It is configured to be shiftable in a plane parallel to the optical axis.

  Next, as a moving means of the correction lens, according to Japanese Patent Application Laid-Open No. 9-80520 filed by the present applicant, a moving coil type actuator having the following configuration is used. The correction lens member is provided with respective coils for the yawing direction and the pitching direction. On the other hand, a magnet is attached to the member on the lens barrel body side corresponding to this coil, and a kind of electromagnetic actuator is provided. Configure. Electromagnetic force is generated by passing a current through the coils for the yawing direction and the pitching direction, and the correction lens is moved in each direction.

  Note that, as described above, if the correction lens is not driven and controlled by supplying current to the coil, the correction lens falls in the direction of gravity and lies down due to its own weight. In order to avoid this, Japanese Patent Laid-Open No. 9-80561 of the present applicant proposes an electromagnetic lock mechanism that electromagnetically locks the correction lens to its approximate optical center using a latch solenoid.

  In still cameras, particularly single-lens reflex cameras, shake correction operates while the release button of the camera is half-pressed. Specifically, the above-described electromagnetic correction is performed by half-pressing the release button of the camera. The lock mechanism releases the electromagnetic lock of the correction lens and starts shake correction. The correction lens controls the drive coil by energizing it, shifts it according to the detected amount of camera shake, and corrects the shake of the imaging surface, film surface, or viewfinder image. On the other hand, when the half-press of the release button is released, the shake correction that is being performed is terminated, and the correction lens is locked to the approximate optical center by the electromagnetic lock mechanism.

Japanese Patent Laid-Open No. 9-80520

However, such conventional shake correction camera and shake correction camera system have the following problems.
(First problem: Finder appearance and related problems)
The first problem is the appearance of the finder image when the half-press of the release button is released, and a problem related thereto.

  An example is given for a single-lens reflex camera. When the release button is half-pressed, shake correction is performed, and while the half-press is released, the correction lens must be in a mechanically fixed state such as an electromagnetic lock. Or, every time the half-press is released, the electromagnetic noise of the correction lens is released, or the operation sound of the latch solenoid when electromagnetically locking is given, and the user is bothered.

  FIG. 2 schematically shows an electromagnetic lock mechanism of a correction lens disclosed in Japanese Patent Application Laid-Open No. 9-80561 filed by the present applicant. The latch solenoid is composed of a magnetized lock pin 31, a coil 33, and a suction plate 32, and the lock pin 31 moves when a current is supplied to the coil 33 in a predetermined direction or in the opposite direction. On the other hand, a lock plate 30 is attached to the correction lens 4, and a lock hole 30 a slightly larger than the lock pin 31 is formed in the lock plate 30. In a state where the correction lens 4 is electromagnetically locked, the lock pin 31 is inserted into the lock hole 30a of the lock plate 30, and the correction lens 4 is substantially fixed at the optical center position. When releasing the electromagnetic lock of the correction lens 4, the coil 33 is energized in a predetermined direction, the lock pin 31 is extracted from the lock hole 30 a of the lock plate 30, and is attracted to the suction plate 32. On the other hand, when the correction lens 4 is electromagnetically locked, the coil 33 is energized in a predetermined direction while holding the correction lens at the approximate center position so that the lock pin 31 can be inserted into the lock hole 30a, and the lock pin 31 is locked into the lock hole 30a. Insert in and lock the electromagnetic. In this case, the problem is that the lock hole 30a is larger than the diameter of the lock pin 31 in consideration of the control error when the correction lens 4 is held at the approximate center position for electromagnetic locking. Must be. In such a case, after the electromagnetic lock is completed and the driving of the correction lens is completed due to the allowance, the difference between the diameter of the lock hole 30a and the diameter of the lock pin 31 (referred to as lock play) is about the correction lens. 4 falls in the direction of gravity. This amount is an amount that can be confirmed by the finder, and there is a problem that the viewfinder image is exposed at the time of electromagnetic lock release / electromagnetic lock operation performed each time the half-press button is turned on / off.

In order to solve this problem, according to Japanese Patent Publication No. 283068 (JP-A-4-21831), when shake correction is ended by a switch for switching start and end of shake correction, the gain of shake correction is set for a predetermined time. By gradually decreasing the time over time, the appearance of the viewfinder is improved by gradually reducing the effect of shake correction, but it is still not sufficient. Also, there are individual differences in how to reduce the shake correction gain and the individual feeling, and the time when the gain drop feels comfortable varies from person to person. Some people feel it. In addition, when this patent publication No. 283068 is applied, even if the user turns off the camera power switch in order to turn off the power of the camera, the shake correction is performed for a while, and the user feels uncomfortable. The same applies when there is an operation member that switches whether or not to perform shake correction. If the state changes from “shake correction on” to “shake correction off”, the shake correction is also performed for a while, and Gives a sense of incongruity.
(Second problem: Problem when electromagnetic lock is not applied)
As a second problem, there is a case where the correction lens is dropped to the movable mechanical end of the movable range without being electromagnetically locked. For example, when the shake correction operation is terminated as described above and the correction lens is electromagnetically locked, the electromagnetic lens is electromagnetically locked by energizing the latch solenoid for the electromagnetic lock while holding the correction lens substantially at the center of its movable range. If it is configured, it is used in places where extreme vibrations occur compared to camera shake, for example, when using the camera shake lens barrel or shake correction camera while swinging, or in an automobile or the like. In rare cases, it is assumed that the correction lens cannot be held at the approximate center and electromagnetic locking fails.
Alternatively, in the case of a system such as a single-lens reflex camera, when considering the case where the lens barrel is attached / detached during the shake correction operation, the lens barrel generally has a power supply from the body. When the lens barrel is attached to or detached from the body, the correction lens is not electromagnetically locked when the lens barrel is attached to or detached from the movable mechanical end. It will fall to the state. Compared with the state in which the correction lens is electromagnetically locked approximately at the center of its movable range, the optical performance is degraded when the correction lens is dropped. Further, when the lens barrel is transported in this state, the correction lens may collide with the movable mechanical end due to vibration or impact, and may be damaged.
(Third problem: Problems related to shake correction during exposure)
Next, the third problem is a problem related to shake correction during exposure.

  Conventionally, the maximum shiftable range (movable range) of the correction lens for correcting the shake is finite, and if it is wide, the shake correction can be performed for a larger shake, but if it is wide, the correction lens is incorporated as much. The lens barrel becomes large. It is desirable that the movable range of the correction lens is a range in which the maximum shake amount that can occur in normal photographing is corrected at the longest time, assuming that the longest time is taken. However, there is no guarantee that the correction lens will be located near the center of the movable range at the timing when the user presses the release button fully due to shake correction started by half-pressing the release button, and when the user takes a picture. The correction lens is located at a position greatly deviated from the center of the movable range. When the shutter is opened and exposure is performed in this state, depending on the amount of shake, the correction lens reaches the limit of its movable range during exposure, and it becomes impossible to correct shake further, and the resulting photo, or The imaging result is likely to have no effect of shake correction. However, if the movable range of the shake correction lens is made sufficiently wide, this problem will be solved, but the lens barrel itself into which the correction lens is inserted becomes large, and the cost increases. Therefore, according to Japanese Patent Publication No. 2820254 (Japanese Patent Laid-Open No. Sho 63-129624), in order to effectively use the movable range of shake correction, the shake correction is performed after the correction lens is centered at the center of the movable range immediately before exposure. It has been proposed to start. However, the following problems arise.

  According to Japanese Patent No. 2820254 (Japanese Patent Laid-Open No. 63-129624), since the exposure is performed after the centering of the correction lens performed before the exposure is completed, the position of the correction lens immediately before the centering of the correction lens is Specifically, due to shake correction started by half-pressing the release button, it is uncertain where the correction lens is located within the movable range at the timing when the user fully presses the release button, and the position where it is centered Is larger, the time required for centering becomes longer. Therefore, the time lag from when the user fully presses until the shutter opens and exposure is changed. In particular, users who use high-end cameras are more strict with this change in time lag. When shake correction is applied, it is not allowed that the time lag becomes longer or the time variation becomes larger.

  In the case of a single-lens reflex camera, according to the prior art, a DC motor is often used for the main mirror up performed immediately before exposure and the mirror down performed after exposure. At the start of this, a very large inrush current flows through this DC motor. Further, when the movement of the mirror up / down mechanism mechanism is rapidly stopped at the end of mirror up and mirror down, the DC motor may be energized in the reverse direction (called reverse energization). In this case as well, a large current flows through the DC motor. Similarly, a DC motor is also used for film winding that starts after exposure, and a large current flows through the DC motor at the same time when winding starts and ends. In such a camera, the circuit for shake correction, the actuator, and the DC motor power for mirror up, down, and winding are mainly supplied from a common battery. The large current flows from the battery by overlapping the timings of large down and winding currents and the centering operation before exposure, the shake correction operation, or the electromagnetic lock or electromagnetic lock release operation described above. Since the battery voltage is suddenly decreased, the electric circuit of the camera does not operate normally. That is, not only does the shake correction operation not operate normally, but also the operation of the camera, for example, the exposure operation, winding up. May cause an abnormality in the operation of the machine.

As described above, the problems of the present invention are to solve the first problem, the appearance of the finder, the second problem, the problem when the electromagnetic lock is not achieved, and the third problem, the problem related to shake correction at the time of exposure. Can do.
The first to third problems are independent problems, and by solving each of them, the reliability of the camera system including the shake correction lens and the shake correction lens can be improved.

The present invention includes a shake correction optical system that constitutes at least a part of a photographing lens and is movable within a movable range in order to correct a shake generated in a camera, and a drive unit that drives the shake correction optical system A lock unit that locks the shake correction optical system within the movable range, a first operation member that terminates driving of the driving unit being driven, and a second unit that switches the power supply of the camera from on to off. And the first operating member for a first time after the first operating member is operated, the driving unit continues to drive, and the power is turned off by the second operating member before the first time elapses. When the operation for switching to is started, the drive unit starts to attenuate the drive, and the drive by the drive unit is attenuated for a second time, and the shake correction optical system is moved by the lock unit after the second time has elapsed. Lock within the movable range And control means, to shake correcting camera having.

1 is a block diagram of a shake correction camera according to the present embodiment. It is an image figure of the electromagnetic lock mechanism concerning this embodiment. It is a timing chart figure when releasing half-press of the release button concerning this embodiment. It is a timing chart figure when the main switch concerning this embodiment is turned off. It is a timing chart figure when the main switch concerning this embodiment is turned off. It is a timing chart figure when the main switch concerning this embodiment is turned ON. It is a timing chart figure when the release button concerning this embodiment is fully pressed. FIG. 6 is a timing chart when the shake correction mode selector according to the present embodiment is turned off.

  Hereinafter, embodiments of the present invention will be described using specific examples. Note that the means for moving the correction lens in two directions orthogonal to the optical axis, the position detection mechanism of the correction lens, etc. are based on the prior art, and other differences from the prior art will be explained. Although there are two mechanisms required in the yawing direction and the pitching direction in the mechanism and circuit for detecting the position and driving of the correction lens, etc., the configuration is the same in each direction.

  FIG. 1 is a block diagram showing an embodiment of a shake correction camera in which the present invention is applied to a single-lens reflex camera, and includes a camera body 1 and a lens barrel 2 having a shake correction function that can be attached to and detached from the camera body 1.

  In the camera body 1, there is a body MCU 20, which is a one-chip microcomputer, and controls all operations on the camera side. The body MCU 20 includes a half-press switch 23 that is turned on by half-pressing a release button (not shown), a full-press switch 24 that is turned on by fully pressing the release button, and almost all operations including shake correction related operations. The main switch 22, the film feed circuit 25, the mirror-up drive circuit 26, and the inter-lens communication circuit 21 are connected to prohibit the operation on the camera body side and prohibit almost all the camera side operations in the off state. Has been.

  The body MCU 20 can recognize the states of the main switch 22, the half-press switch 23, and the full-press switch 24, and communicates with the lens barrel with the lens barrel 2 attached through the inter-lens communication circuit 21. be able to. Further, the body MCU 20 controls the film feeding motor 27 through the film feeding circuit 25, and performs control such as winding and rewinding of the photographic film. In addition, the body MCU 20 can control the mirror drive motor 28 through the mirror up drive circuit 26 to raise or lower the mirror (not shown).

  In addition, the camera body 1 has a shutter mechanism (not shown) for exposing the photographic film, and is controlled by the body MCU 20 using a driving circuit according to a known technique. Further, a power supply for operating each circuit and supplying to the lens barrel 2 and other electrical circuits are necessary, but they are omitted because they are not related to the gist of the present invention.

  On the other hand, the lens barrel 2 includes the following.

  Reference numerals 3, 4, and 5 are photographing lenses, and 4 of them is a correction lens, and within a movable range in a plane orthogonal to the optical axis 6 in order to perform shake correction operation by the shake correction optical system driving means 34. It is configured to be shiftable with. A correction lens position detection circuit 13 detects the position of the correction lens 4.

  Reference numeral 14 denotes a correction lens driving circuit for driving the correction lens 4 during a shake correction operation and when the correction lens 4 is locked near the approximate center of its movable range. Feedback control is performed so as to keep the correction lens 4 at the correction lens target position based on a correction lens target position signal from the lens MCU 10 described later and a correction lens position signal from the correction lens position detection circuit 13.

  As the lock means for locking the correction lens 4 to the approximate center of its movable range, the lock mechanism shown in FIG. 2 according to the above-described prior art is used, 15 is an electromagnetic lock drive circuit, and the latch shown in FIG. The energization of the coil 33 constituting the solenoid is controlled.

  Reference numeral 12 denotes a shake detection circuit that detects a shake generated in the lens barrel 2. For example, the angular velocity due to the shake generated in the lens barrel 2 is detected and output as a shake signal.

  Reference numeral 16 denotes an EEPROM as rewritable nonvolatile storage means, which stores adjustment values related to shake correction or predetermined parameters related to the present invention.

The lens barrel 2 is provided with a shake correction mode selector as shown in FIG. The shake correction mode selector has a state in which a user operates a shake correction state (shake correction on) and a state in which no shake correction is performed (shake correction off). This is linked to the shake correction mode switch a and the 18 shake correction mode switch b. As shown in FIG. 8, when the shake correction mode selector is set to “shake correction on”, the shake correction mode switch a17 is “on”, the shake correction mode switch b18 is “off”, and “shake correction is off”. Then, the shake correction mode switch a17 is in the “off state”, and the shake correction mode switch SWb16 is in the “on state”.
The shake correction mode selector is suitable for changing from “shake correction on” to “shake correction off” and vice versa by a known technique. The structure is such that it does not stop at the intermediate position due to a click feeling, and when it is in the intermediate position, both the shake correction mode switch a17 and the shake correction mode switch b18 are in the “off state”, and “shake correction” It is configured to recognize a change from “on” to “shake correction off” and vice versa.

  Reference numeral 10 denotes a lens MCU constituted by a one-chip microcomputer, which recognizes the states of the shake correction mode switch a17 and the shake correction mode switch b18 and controls all the circuits in the lens. Communication with the camera body 1 is performed through the inter-body communication circuit 11 while the lens barrel 2 is attached to the camera body 1. In addition, the power of the circuit in the lens barrel is supplied from the camera body 1 by a known technique.

  Next, a specific method for solving the first problem, that is, the appearance of the finder and related problems will be described with reference to FIGS. 3, 4, and 5. 3, 4, and 5 show the state of the main switch 22, the half-press switch 23, and the full-press switch 24 of the camera body 1, an instruction from the camera body 1 to the lens barrel 2, and a lens mirror corresponding to the instruction. 3 is a timing chart showing the operation of a cylinder 2.

  This is illustrated in FIG. First, the operation on the camera body 1 side will be described. All the operations of the camera body 1 are performed by the body MCU 20, and the operations of the body MCU 20 will be described below. The body MCU 20 recognizes the states of the main switch 22, the half-push switch 23, and the full-push switch 24. In this example, the main switch 22 is already turned on, and the half-push switch 23 is turned on at timing t10. Recognize that When the body MCU 20 recognizes that the half-press switch 23 is turned on at timing t10, the body MCU 20 issues a “shake correction start instruction” to the lens barrel 2 through the inter-lens communication circuit 21. In addition, the body MCU 20 issues a “shake correction end instruction” to the lens barrel 2 through the inter-lens communication circuit 21 at the timing t14 when the half-press switch 23 is turned off.

On the other hand, the lens barrel 2 operates as follows in response to the above instruction from the body MCU 20. All the operations of the lens barrel 2 are performed by the lens MCU 10. At the timing when the operation of FIG. 3 starts, the correction lens 4 is already locked to the approximate center of its movable range by the electromagnetic lock driving circuit 15 and the electromagnetic lock mechanism shown in FIG. Assume that it is locked. When the lens MCU 10 receives the “shake correction start instruction” from the body MCU 20 through the inter-body communication circuit 11 at the timing t11, the lens MCU 10 can easily release the electromagnetic lock to the correction lens driving circuit 14 at the timing t12. An instruction is given to hold the position at a position slightly lifted from the current correction lens position. More specifically, the lens MCU 10 recognizes the position of the correction lens 4 at the timing t11 from the signal from the correction lens position detection circuit 13, and uses the position slightly lifted as a correction lens target position as a correction lens drive circuit. 14 is instructed. Accordingly, the correction lens driving circuit 14 performs feedback control so that the correction lens 4 is positioned at the instructed correction lens target position. Next, the lens MCU10 is in a direction in which the electromagnetic lock is released to the coil 33 of the electromagnetic lock latch solenoid through the electromagnetic lock driving circuit 15 from the timing t12 until the timing t13 after a predetermined time T4 (t12 to t13) has elapsed (in FIG. 3). In the example, energization is performed in the + direction).
As a result, the electromagnetic lock pin 31 is removed from the electromagnetic lock hole 30a by the electromagnetic lock mechanism shown in FIG. 2, and the correction lens 4 becomes freely movable within the predetermined movable range. The “correction lens movable range upper limit” and the “correction lens movable range lower limit” shown in FIG. 3 are those of the correction lens corresponding to the backlash amount of the lock hole 30a in the “electromagnetic locked state” shown in FIG. This diagram schematically shows that the movable range of the correction lens 4 in the “state in which the electromagnetic lock is released” is expanded from the movable range. Next, when the electromagnetic unlocking operation from the timing t11 to the timing t13 is completed, the lens MCU 10 determines the image plane, the image plane, and the image plane according to the shake amount signal generated in the lens barrel 2 detected by the shake detection circuit 12 from the timing t13. Alternatively, the correction lens target position is instructed to the correction lens driving circuit 14 to drive the correction lens 4 so as to correct the shake on the imaging surface. The correction lens drive circuit 14 drives the correction lens 4 based on the instructed correction lens target position and the correction lens position signal from the correction lens position detection circuit 13, and shake due to camera shake of the image surface or the imaging surface. It is corrected.

  Next, when the lens MCU 10 receives a “shake correction end instruction” from the body MCU 20 through the inter-body communication circuit 11 at the timing t14, the lens MCU 10 receives a predetermined time T1 (t16 to t17) from the EEPROM 16 at t15, and The T2 (t17 to t18) is read, and the shake correction operation started from the timing t13 is continuously performed from the timing t16 when the reading of the EEPROM is finished to the timing t17 when the read T1 time elapses. The correction lens target position is calculated by Equation 1 from the timing t17 when the time T1 has elapsed.

(Equation 1)
Correction lens target position = W × LC + (W−1) × LC0
Here, W is the correction lens target position weighting ratio calculated by Equation 2, and is a function that decreases in proportion to the elapsed time t from the timing t17. W = 1 at the timing t17 and W at the timing t18. = 0.

(Equation 2)
W = (T2-t) / T2
LC is a shake correction amount, which is calculated from the output of the shake detection circuit 12, and when this amount is instructed to the correction lens drive circuit 14 as a correction lens target position, the shake performed from timing t13 to timing t17. Similar to the correction operation, the image plane or the image pickup surface is shaken appropriately. LC0 is an electromagnetic lock center position that is a target position when the correction lens 4 is electromagnetically locked by the electromagnetic lock mechanism shown in FIG. 2, and is the center position of the backlash of the lock hole 30a in FIG. . T2 is a value read from the EEPROM 16 from timing t15 to timing t16. As a result, during the period from timing t17 to timing t18, the correction lens target position gradually decreases in shake correction gain according to the elapsed time from timing t17, and gradually approaches the electromagnetic lock center position LC0. The electromagnetic lock center position LC0 is reached at timing t18, and the correction lens drive circuit 14 controls the correction lens 4 to the correction lens target position.

  Next, from timing t18, the correction lens target position is maintained at the electromagnetic lock center position LC0, and the correction lens position detected by the correction lens position detection circuit 13 is within a predetermined range, specifically, the electromagnetic lock center position LC0 is set. It is determined whether or not it has been continuously positioned for a predetermined time T3 (t18 to t19) within a range of ± predetermined value ΔLlock1 as a reference, and since it has been satisfied at timing t19, an electromagnetic lock latch solenoid through the electromagnetic lock drive circuit 15 The coil 33 is energized for a predetermined time T5 (t19 to t20) in the direction in which the coil 33 is electromagnetically locked (in the example of FIG. 3, the current is applied in the negative direction). Thus, the lock pin 31 is inserted into the lock hole 30a by the electromagnetic lock mechanism shown in FIG. 2, and the correction lens 4 is electromagnetically locked at the approximate center of the movable range.

  The predetermined value ΔLlock1 is set to a value that is at least smaller than the amount of play on one side of the lock hole 39a shown in FIG. 2, and the position of the correction lens 4 is continuously located in this range for a predetermined time T3. Thus, it is determined that the lock pin 31 is securely inserted into the lock hole 30a by energizing the coil 33 of the electromagnetic lock latch solenoid from timing t19.

  As described above with reference to FIG. 3, the shake correction operation is started by turning on the half-press switch 23 which is turned on by half-pressing the release button, and when the half-press switch is released and the half-press switch 23 is turned off. The shake correction is continued for a predetermined time T1, and thereafter, for a predetermined time T2, the shake correction gain decreases with time, and the correction lens 4 is centered at the electromagnetic lock center position in the approximate center of the movable range. Thus, the correction lens 4 is electromagnetically locked at the approximate center of its movable range. In the prior art, at the end of shake correction, the shake correction gain is simply decreased with time. However, the shake correction is continued for a predetermined time T1, and then the shake correction gain is increased over the predetermined time T2. Since it is made to reduce, it does not give a sense of incongruity to the user who observes with a finder image rather than the thing by a prior art. Further, since the predetermined times T1 and T2 are values read by the EEPROM 16, which is a rewritable nonvolatile storage means, the user can bring the lens barrel according to the present embodiment into a service center, for example. For example, the predetermined values T1 and T2 written in the EEPROM 16 can be rewritten by a known technique, and can be optimized according to the feeling of each user. Compared to the technique, it is possible to improve the feel of the finder image at the end of shake correction after the half-press is turned off.

Next, an operation when the main switch 22 of the camera body 1 is turned off during the shake correction operation will be described with reference to FIG.
The operation from the timing t30 to the timing t36 in FIG. 4 is the same as the operation from the timing t10 to the timing t16 in FIG. 3, and the operation from the timing t37 will be described without description. First, the operation on the camera body 1 side will be described. All the operations of the camera body 1 are performed by the body MCU 20, and the operations of the body MCU 20 will be described below. The body MCU 20 recognizes that the main switch 22 is turned off at timing t37, and gives an “electromagnetic lock instruction” to the lens barrel 2 through the inter-lens communication circuit 21.

  On the other hand, the lens barrel 2 operates as follows in response to the above instruction from the body MCU 20. All the operations of the lens barrel 2 are performed by the lens MCU 10. At time t37, as in FIG. 3, the shake correction performed during the predetermined time T1 is performed according to the “shake correction end instruction” from the camera body 1, and the predetermined time T1 has not yet elapsed. is there.

  When an “electromagnetic lock instruction” is issued from the camera body 1 at timing t37, the lens MCU10 calculates a corrected lens target position from Equation 3 from timing t38.

(Equation 3)
Correction lens target position = W ′ × LC + (W′−1) × LC0
Here, W ′ is a correction lens target position weighting ratio calculated by Equation 4, and is a function that decreases in proportion to the elapsed time t from timing t38, and at timing t38, W ′ = 1 and at timing t39. W ′ = 0.

(Equation 4)
W ′ = (T2′−t) / T2 ′
LC is a shake correction amount, which is calculated from the output of the shake detection circuit 12. If this amount is instructed as the correction lens target position to the correction lens drive circuit 14, it is performed from timing t33 to timing t38. Similar to the shake correction operation, shake due to camera shake of the image plane or the imaging surface is appropriately performed. LC0 is an electromagnetic lock center position that is a target position when the correction lens 4 is electromagnetically locked by the electromagnetic lock mechanism shown in FIG. 2, and is the center position of the backlash of the lock hole 30a in FIG. . T2 ′ is a value shorter than the predetermined value T2 used in the example shown in FIG. As a result, from timing t38 to timing t39, the correction lens target position gradually decreases in shake correction gain according to the elapsed time from timing t38, and gradually approaches the electromagnetic lock center position LC0. At timing t39, the electromagnetic lock center position LC0 is reached, and the correction lens driving circuit 14 controls the correction lens 4 to the correction lens target position.

  Next, the electromagnetic locking operation of the correction lens from timing t39 to timing t41 is the same as that in FIG.

Next, another embodiment in which the main switch 22 of the camera body 1 is turned off during the shake correction operation will be described with reference to FIG.
The operation of the camera body 1 in FIG. 5 and the operation of the lens barrel 2 from timing t50 to timing t57 are the same as the operations shown in FIG. 4, and only the differences will be described below.

  At the timing t57, the lens MCU 10 performs the shake correction performed during the predetermined time T1 in accordance with the “shake correction end instruction” from the camera body 1 at the timing t57, and the predetermined time T1 has elapsed. It is not in a state.

  When an “electromagnetic lock instruction” is issued from the camera body 1 at timing t57, the lens MCU 10 calculates a corrected lens target position from Formula 5 from timing t58.

(Equation 5)
Correction lens target position = LR0 + (LC0−LR0) × t / T2 ″
Here, t is an elapsed time from timing t58, and LC0 is an electromagnetic lock center position that is a target position when the correction lens 4 is electromagnetically locked by the electromagnetic lock mechanism shown in FIG. The center position LR0 of the backlash of the lock hole 30a is the correction lens position output by the correction lens position detection circuit 13 at timing t58. T2 ″ is a value shorter than the predetermined value T2 used in the example shown in FIG.

  Thus, from timing t58 to timing t59, the correction lens target position gradually approaches the electromagnetic lock center position LC0 according to the elapsed time from timing t58, and becomes the electromagnetic lock center position LC0 at timing t59. The correction lens drive circuit 14 controls the correction lens 4 at the correction lens target position.

  Next, the electromagnetic locking operation of the correction lens from timing t59 to timing t61 is the same as that in FIG.

  As described above with reference to FIGS. 4 and 5, the release button half-pressing operation is released in the same manner as described with reference to FIG. The shake correction operation is performed, and then the shake correction operation is gradually ended over a predetermined time T2. When the main switch 22 of the camera body 1 is turned off, at least the shake correction operation shown in FIG. Compared with the end of the operation, the shake correction operation is completed earlier, and the correction lens 4 is electromagnetically locked to the approximate center position of the movable range. This solves the problem that even if the user turns off the camera power switch to turn off the camera, shake correction is performed for a while and the user feels uncomfortable.

  Next, an embodiment in which the shake correction mode selector of the lens barrel 2 changes from the “shake correction on” state to the “shake correction off” state during the shake correction operation will be described with reference to FIG.

  At the timing t120, the lens MCU 10 is in a state of performing a shake correction operation in accordance with the “shake correction start instruction” from the camera body 1 as in FIG.

  At the timing t120, the lens MCU 10 changes the state of the shake correction mode selector from “shake correction on state (shake correction mode switch a is on and shake correction mode switch b is off)” to “intermediate position state (shake correction). Since the mode switch a is changed to the state (the state in which the mode switch a is turned off and the shake correction mode switch b is turned off), the lens MCU 10 sets the correction lens target position from the timing t120 in the same manner as the timing t58 to the timing t59 in FIG. After the timing t121 when the correction lens target position reaches the electromagnetic lock center position, the correction lens target position is held at the electromagnetic lock center position. Here, t is an elapsed time from the timing t120, and LC0 is an electromagnetic lock center position that is a target position when the correction lens 4 is electromagnetically locked by the electromagnetic lock mechanism shown in FIG. The center position LR0 of the backlash of the lock hole 30a is the correction lens position output by the correction lens position detection circuit 13 at the timing t120. Further, T2 ″ is a value shorter than the predetermined value T2 used in the example shown in FIG. 8. In this case, the value is the same as that when the main switch 22 shown in FIG.

  Thus, from timing t120 to timing t121, the correction lens target position gradually approaches the electromagnetic lock center position LC0 according to the elapsed time from timing t120, and becomes the electromagnetic lock center position LC0 at timing t121. Thereafter, it is held in that position. Further, the correction lens drive circuit 14 controls the correction lens 4 to the correction lens target position.

  Next, at the timing t122, the lens MCU 10 changes the state of the shake correction mode selector from the “intermediate position state (state where the shake correction mode switch a is turned off and the shake correction mode switch b is turned off)”. Since the state has changed to “state (state in which the shake correction mode switch a is off and the shake correction mode switch b is on)”, the lens MCU10 performs an operation of electromagnetically locking the correction lens 4 from timing t122. The operation of electromagnetic locking of the correction lens 4 performed by the lens MCU 10 from the timing t122 to the timing t124 is similar to the operation from the timing t59 to the timing t61 in FIG.

As described above with reference to FIG. 8, when the shake correction mode selector changes from the “shake correction on” state to the “shake correction off” state while the shake correction operation is performed, as shown in FIG. 5. As in the case where the main switch 22 of the camera body 1 is turned off, the shake correction operation is completed earlier than at the end of the shake correction operation shown in FIG. 3, and the correction lens 4 is moved to the approximate center of its movable range. Electromagnetic lock to position. In addition, when the shake correction mode selector changes from the “shake correction on state” to the “intermediate position state” during the change from the “shake correction off state”, the correction lens 4 is already centered at the electromagnetic lock center position. Since it is held at that position, it is not necessary to center the correction lens when the shake correction mode selector changes to the “shake correction OFF state”, and the correction lens 4 can be electromagnetically locked more promptly.

  This solves the problem that even if the user tries to turn off the shake correction and the shake correction mode selector is turned off, the shake correction is performed for a while and the user feels uncomfortable.

  Next, a solution for the second problem, that is, the problem when the correction lens 4 is not electromagnetically locked for some reason will be described with reference to FIG.

  First, the operation on the camera body 1 side will be described. All the operations of the camera body 1 are performed by the body MCU 20, and the operations of the body MCU 20 will be described below. The body MCU 20 recognizes the states of the main switch 22, the half-press switch 23, and the full-press switch 24. In this example, it is assumed that the main switch 22 is first turned off. At timing t70, the main switch 22 is turned on. At this time, when the half-push switch 23 and the full-push switch 24 are off, the lens is passed through the inter-lens communication circuit 21 at a predetermined interval from timing t71. The “electromagnetic lock instruction” is repeatedly given to the lens barrel 2. Further, from the timing t78 when the main switch 22 is turned off to the timing t79, the “electromagnetic lock instruction” is not given to the lens barrel 2, and after the timing t79 when the main switch 22 is turned on again, timing t80 and timing t81. The “electromagnetic lock instruction” is repeatedly given to the lens barrel 2 through the inter-lens communication circuit 21 at the timing t82 and at a predetermined time interval, for example.

  On the other hand, the lens barrel 2 operates as follows in response to the above instruction from the body MCU 20. All the operations of the lens barrel 2 are performed by the lens MCU 10. At the timing when the operation of FIG. 6 is started, the correction lens 4 is in a state where the electromagnetic lock has been released for some reason, and the correction lens 4 has moved to the mechanical end of the movable range due to gravity (falling). A) state. When receiving an “electromagnetic lock instruction” from the body MCU 20 through the inter-body communication circuit 11 at the timing t71, the lens MCU 10 determines whether or not the correction lens 4 is electromagnetically locked. Thus, the position of the correction lens 4 is recognized, and it is determined whether or not the correction lens position is within the predetermined range ± ΔLlock2 with respect to the electromagnetic lock center position. In this case, the correction lens 4 is within the predetermined range ± ΔLlock2. If it is determined that the correction lens 4 is not electromagnetically locked, the correction lens target position is calculated by Equation 6.

(Equation 6)
Correction lens target position = LR0 + (LC0−LR0) × t / T7
Here, t is an elapsed time from the timing t71, and LC0 is an electromagnetic lock center position that is a target position when the correction lens 4 is electromagnetically locked by the electromagnetic lock mechanism shown in FIG. The center position LR0 of the backlash of the lock hole 30a is the correction lens position output by the correction lens position detection circuit 13 at the timing t71. T7 is set to an appropriate predetermined value.

  By instructing the correction lens drive circuit 14 of the calculated correction lens target position, the correction lens 4 substantially reaches the electromagnetic lock center position LC0 at the timing t72 when the predetermined time T7 has elapsed from the timing t71, and then the timing t72. From FIG. 3, the lock pin 31 is inserted into the lock hole 30a by the electromagnetic lock mechanism shown in FIG. 2 by the operation similar to the operation of the electromagnetic lock from the timing t18 to the timing t20 in FIG. The correction lens 4 is electromagnetically locked at the approximate center of its movable range.

  The predetermined range ± Llock2 for determining whether or not the correction lens 4 is electromagnetically locked is set to a value larger than the amount of play caused by the lock hole 30a shown in FIG. 2, and the position of the correction lens 4 is within this range. If it does not fit, the correction lens 4 has a value that can be regarded as not being electromagnetically locked.

  Similarly, the lens MCU 10 receives an “electromagnetic lock instruction” from the camera body 1 at timing t77, timing t80, timing t81, and timing t82. In this case, the position of the correction lens 4 is Since it is within the predetermined range ± ΔLlock2 with respect to the electromagnetic lock center position LC0, the correction lens 4 is not electromagnetically locked again, assuming that the electromagnetic lens is locked.

  As described above, when the camera body 1 and the lens barrel 2 shown in FIG. 6 are operated and the correction lens is not electromagnetically locked for some reason and is in a gravity drop state, the main switch 22 of the camera body 1 is turned on. Even in the above state or in the off state, the user returns by turning on the main switch 22, and the correction lens 4 is surely electromagnetically locked. In addition, there is no need to add a special circuit or the like for solving this problem, and the cost is not increased.

Next, an embodiment for solving the third problem, that is, the problem relating to shake correction during exposure will be described with reference to FIG.

  FIG. 7 is a timing chart showing an instruction to the lens barrel 2 of the camera body 1 during exposure and an operation of the lens barrel 2 in response to the instruction.

  First, the operation on the camera body 1 side will be described. All the operations of the camera body 1 are performed by the body MCU 20, and the operations of the body MCU 20 will be described below. The body MCU 20 recognizes the states of the half-push switch 23 and the full-push switch 24. In this example, the half-push switch 23 is already turned on and the full-push switch 24 is turned on at timing t100. Upon recognition, after instructing the “lens correction stop” to the lens barrel 2 through the inter-lens communication circuit 21, the mirror drive motor 28 is driven through the mirror drive circuit 26 for mirror up after a predetermined time T13 has elapsed. Start. Subsequently, at a timing t102 at which a predetermined time T14 has passed since at least the influence of the battery voltage due to the start of driving of the mirror driving motor 28 is substantially reduced, the exposure is performed on the lens barrel 2 through the inter-lens communication circuit 21. In addition to instructing “time shake correction start instruction”, the lens barrel 2 is instructed through the inter-lens communication circuit 21 for the time from the timing t102 to the exposure start, in the example of FIG.

  Next, the body MCU 20 reversely energizes the mirror drive motor 28 through the mirror drive circuit 26 at the timing when the mirror up is almost finished, and opens and closes the shutter at the timing t105 to expose the film. After that, when the opening / closing of the shutter is completed at timing t106, the “camera shake correction stop instruction” is instructed to the lens barrel 2 through the inter-lens communication circuit 21 at timing t107, and then at the timing t109 when a predetermined time T15 has elapsed. The drive of the mirror drive motor 28 is started through the mirror drive circuit 26 for the down, and the drive of the film feed motor 27 is started through the film feed circuit 25 for the film winding. Thereafter, when the body MCU 20 finishes the mirror-down and film winding operations at timing t110, it instructs the lens barrel 2 to “shake correction start instruction” through the inter-lens communication circuit 21 at timing t111. In the example of FIG. 7, reverse energization is applied to the mirror driving motor 28 and the film feeding motor 27 for a predetermined time at the end of the mirror-down operation after the end of exposure and at the end of film winding, respectively. I try to apply. As a result, the power supply voltage of the camera body 1 drops rapidly. Further, the start of shake correction is given to the lens barrel 2 at timing t111 after the energization of the mirror driving motor 28 and the film feeding motor 27 is finished at timing t110 so that this timing and the start of shake correction do not overlap. I'm trying to tell you. In addition, when either the mirror driving motor 28, the film feeding motor 27, or both are not braked using reverse energization at the end of the mirror down operation and the end of film winding, The lens barrel 2 is instructed to start shake correction at the timing of either the end of energization of the mirror drive motor 28 for down or the end of energization of the film feed motor 27 for film winding. It doesn't matter.

  On the other hand, the lens barrel 2 operates as follows in response to the above instruction from the body MCU 20. All the operations of the lens barrel 2 are performed by the lens MCU 10. It is assumed that the shake correction operation has already been performed in accordance with an instruction from the camera body 1 at the timing when the operation of FIG.

  When receiving the “shake correction stop instruction” from the body MCU 20 through the inter-body communication circuit 11 at the timing t100, the lens MCU 10 maintains the current correction lens position in the correction lens driving circuit 15 at the timing t101. Instruct. Specifically, the lens MCU 10 recognizes the position of the correction lens 4 at the timing t101 by a signal from the correction lens position detection circuit 13, and instructs the correction lens drive circuit 14 to use the position as the correction lens target position. Accordingly, the correction lens driving circuit 14 performs feedback control so that the correction lens 4 is positioned at the instructed correction lens target position.

  Next, at timing t102, the lens MCU10 receives an “exposure shake correction start instruction” and “time T10 until exposure start” from the body MCU20 through the inter-body communication circuit 11, and from timing t103, The correction lens 4 is held until the timing t104 when the predetermined time T11 necessary for stabilizing the shake correction operation at the time of exposure is at least stabilized with respect to the exposure time indicated by the time T10 (corresponding to the timing t105). Center to the center of the movable range. Specifically, the correction lens drive circuit 15 is instructed to the correction lens drive circuit 14 with the center position of the movable range of the correction lens 4 as the correction lens target position. Alternatively, as shown in FIG. 7, like the timing t <b> 71 to the timing t <b> 72 in FIG. 6, the correction lens target position is a straight line starting from the correction lens position at the timing t <b> 103 and the center position of the movable range of the correction lens 4 as the end point. The correction lens 4 may be centered by changing. As a result, the correction lens driving circuit 14 performs feedback control so that the correction lens 4 is positioned at the instructed correction lens target position, and if the time from the timing t103 to the timing t104 is sufficient, the correction lens 4 has its movable range. Even when a camera body with a short time lag is mounted, the correction lens 4 is centered at the approximate center of its movable range as much as possible.

  Next, the lens MCU 10 starts shake correction for exposure at a timing t104 that is a predetermined time T11 before the timing t105 of the exposure start timing instructed from the camera body 1, and specifically, is detected by the shake detection circuit 12. The correction lens target position is instructed to the correction lens drive circuit 14 to drive the correction lens 4 so as to correct the shake on the image plane or the imaging plane in accordance with the shake amount signal generated in the lens barrel 2 To do. The correction lens drive circuit 14 drives the correction lens 4 based on the instructed correction lens target position and the correction lens position signal from the correction lens position detection circuit 13, and shake due to camera shake of the image surface or the imaging surface. It is corrected.

  Next, when the lens MCU 10 receives a “shake correction stop instruction” from the body MCU 20 through the inter-body communication circuit 11 at the timing t107, the lens MCU 10 sends the current correction lens position to the correction lens driving circuit 14 at the timing t108. To maintain. Specifically, the lens MCU 10 recognizes the position of the correction lens 4 at the timing t108 by a signal from the correction lens position detection circuit 13, and instructs the correction lens drive circuit 14 to use the position as the correction lens target position. Accordingly, the correction lens driving circuit 14 performs feedback control so that the correction lens 4 is positioned at the instructed correction lens target position.

  Next, when the lens MCU 10 receives a “shake correction start instruction” from the body MCU 20 through the inter-body communication circuit 11 at the timing t111, the lens MCU 10 causes the shake detection circuit 12 to send the correction lens drive circuit 15 at the timing t112. In accordance with the detected shake amount signal generated in the lens barrel 2, the correction lens target position is set to the correction lens drive circuit 14 to drive the correction lens 4 so as to correct the shake on the image plane or the imaging plane. Instruct. The correction lens drive circuit 14 drives the correction lens 4 based on the instructed correction lens target position and the correction lens position signal from the correction lens position detection circuit 13, and shake due to camera shake of the image surface or the imaging surface. It is corrected.

  As described above, the operation of the camera body 1 shown in FIG. 7 and the lens barrel 2 attached to the camera body 1 causes the correction lens 4 to be centered immediately before exposure, and shake correction is started almost from the center of its movable range. The amount of shake that can be corrected is kept large. Further, the range of the correction lens capable of correcting the shake during exposure can be mechanically increased without increasing the cost. In addition, the time lag from the full pressing of the release switch to the exposure is not changed, and even if this time lag differs depending on the camera body, the correction lens 4 is set to the approximate center position of the movable range before the exposure in accordance with the time lag time. Centered. For example, when a camera body with a short time lag is attached, the correction lens 4 can be centered as much as possible at the approximate center position of the movable range while ensuring at least the time T11 until the shake correction is stabilized at the exposure time. If a camera body with a long time lag is mounted, of course, the correction lens 4 is centered at the approximate center position of the movable range.

  In addition, shake correction is performed at the timing when the load of the power source of the camera body 1 is large, specifically, at the driving start and driving stop timing of the mirror up driving motor 28 and the film feeding motor 27 for mirror up and down. Since the camera is stopped and the correction lens 4 is held in that position, the shake correction operation and the large current consumption timing of the camera body 1 do not overlap, and the battery voltage of the camera body 1 drops sharply. In other words, not only the shake correction operation does not operate normally, but also the camera body 1, such as the exposure operation, the winding operation, etc., is no longer abnormal.

DESCRIPTION OF SYMBOLS 1; Camera body, 2; Lens barrel, 3, 5; Shooting lens, 4; Shooting lens (correction lens), 6: Shooting optical axis, 10; Lens MCU (one-chip microcomputer), 11; , 12; shake detection circuit, 13; correction lens position detection circuit, 14; correction lens drive circuit, 15; electromagnetic lock drive circuit, 16; EEPROM (rewritable non-volatile storage means), 17; shake correction mode switch a, 18; shake correction mode switch b, 20; body MCU (one-chip microcomputer), 21; inter-lens communication circuit, 22; main switch, 23; half-press switch, 24; full-press switch, 25; film feeding circuit, 26; mirror drive circuit, 27; film feeding motor, 28; mirror drive motor.

Claims (2)

At least a portion configured and a movable in blur correction optical system in a variable dynamic range in order to correct the shake occurring in the camera taking lens,
A driving unit for driving the blur correction optical system,
A lock portion you locking within the movable range correction optical system the shake,
A first operating member to terminate the drive of the front asked moving parts in the drive,
A second operating member for switching off the power of the camera from on
In the first operation between when a member is operated in the first continues driving by the drive unit, turns off the power supply by the second operating member before lapse between when the first as the switching operation is performed starting attenuation of driving by the drive unit during the second time to attenuate the driving by the driving unit, the shake correcting optical system by the locking unit after lapse between when the second and that control means abolish joint within said movable range,
That having a vibration is corrected camera. Before SL control means starts attenuation of driving by the drive unit and the operation to switch to the first off the power by the second operating member before lapse between when the is performed, the second until during the time of 2 attenuates as time elapses driving by the driving unit, and, before moving the blur correction optical system position anchored me by the front Symbol locking portion
請 Motomeko 1, wherein the anti-shake camera.