JP6347658B2 - Lens barrel, optical device, and imaging apparatus - Google Patents

Description

  The present invention relates to a lens barrel, an optical apparatus, and an imaging apparatus.

  An imaging apparatus such as a digital camera that can capture an image in a memory has been proposed. The digital camera acquires a captured image using an image sensor such as a CCD or a CMOS. The digital camera performs a zoom operation to change the shooting angle of view by changing the interval between the plurality of shooting lens groups. In recent years, there has been a strong demand for a thinner camera with a higher zoom magnification, and it is desirable to have a configuration in which the moving stroke of the photographing lens group is increased and the size is reduced as much as possible. In addition, there has been proposed an imaging apparatus that corrects blurring of a captured image (image blurring) due to camera shake of a camera operator. The function for correcting image blur is called an image stabilization function. The imaging apparatus corrects the image blur by driving a shake correction lens (anti-vibration lens) inside the photographing lens barrel so as to cancel the shake applied to the apparatus.

  Techniques have been proposed for downsizing an imaging device having a vibration isolation function. Japanese Patent Application Laid-Open No. 2004-228561 discloses an imaging apparatus that can reduce the distance between the lenses in the image stabilizing lens when the apparatus is stored. Patent Document 2 discloses a lens barrel that retracts or intrudes lens holding means in the lens barrel from the optical axis.

JP 2011-141373 A JP 2004-233916 A

  In the photographing apparatus disclosed in Patent Document 1, the effect of downsizing the apparatus is the distance between the lenses, and the downsizing is insufficient. Here, in the lens barrel disclosed in Patent Document 2, the lens holding means is retracted with the corners of the barrier protruding, so that the space efficiency of the lens barrel is not good. In this lens barrel, a load is always applied to the lens holding means while the lens holding means is retracted, and the lens holding means cannot operate in a direction perpendicular to the optical axis. Therefore, the lens holding means cannot be used for posture detection.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lens barrel that can hold a lens holding means during operation and can be reduced in size.

A lens barrel according to an embodiment of the present invention has a base portion, a lens holding portion that holds the lens, and has a retracted state in which the base portion is retracted from the optical axis, and a use state that enters the optical axis. And a spring member that generates a biasing force between the base portion and the lens holding means and switches the biasing direction from a predetermined position, and applies a moving force to the lens holding means. A switching unit that switches the holding unit to the retracted state or the use state, an image sensor holding unit that is provided on the imaging element side from the base unit, and that is provided on the subject side from the base unit, and a lens mirror Barrier means for protecting the cylinder . The spring member biases and holds the lens holding means in the retracted state and the used state. The switching means applies the moving force only when the lens holding means is moved, and applies the moving force when the lens holding means is switched to the retracted state or the use state and is held by the spring member. Absent. The switching unit includes a first switching unit provided in the image sensor holding unit and a second switching unit provided in the barrier unit.

  According to the lens barrel of the present invention, the lens holding means can be held to be operable during retraction, and the size can be reduced.

It is a figure which shows an example of the external appearance of the imaging device of this embodiment. It is an example of the functional block diagram of the imaging device of this embodiment. It is an example of sectional drawing of a photographic lens barrel. It is a figure which shows the structural example of an anti-vibration lens unit. It is a figure which shows the structural example of an anti-vibration lens unit. It is a figure which shows the structural example of an anti-vibration lens unit. It is a perspective view which shows the structure of a barrier means. It is a figure explaining operation | movement of the retracting mechanism of a taking lens-barrel.

FIG. 1 is a diagram illustrating an example of the appearance of the imaging apparatus according to the present embodiment.
FIG. 1A shows a front perspective view of the digital camera 32. FIG. 1B shows a rear view of the digital camera 32. The digital camera 32 is the imaging device of this embodiment. The digital camera 32 has a zoom mechanism that can change the photographing magnification.

  In front of the digital camera 32, there are provided a finder 30 for determining the composition of the subject, auxiliary light 29 for assisting the light source when performing photometric distance measurement, a strobe 31, and a photographing lens barrel 25. The taking lens barrel 25 is the lens barrel of this embodiment.

  On the top surface of the digital camera 32, a release button 26, a zoom switch 27, and a power switch button 28 are arranged. On the back of the digital camera 32, operation buttons 35, 36, 37, 38, 39, 40, a display 34, and a viewfinder eyepiece 33 are arranged. Various functions can be switched by operating the operation buttons. The display 34 has, for example, an LCD. The display 34 displays the image data stored in the memory 48 (FIG. 2) and the image data read from the memory card on the screen. The viewfinder eyepiece 33 is used by the photographer to determine the composition with the eyes and to focus.

FIG. 2 is an example of a functional block diagram of the imaging apparatus according to the present embodiment.
The CPU 54, the ROM 53, and the RAM 55 constitute a control unit that controls the entire digital camera 32. Various components such as a release button 26, operation buttons 35 to 40, a display 34, a memory 48, and a memory card drive 50 are connected via a bus 52.

  Connected to the drive circuit 51 connected to the control unit via the bus 52 are a zoom mechanism 41, a focus drive mechanism 42, a shutter drive mechanism 43, an anti-vibration lens drive means 10, an image sensor 24 such as a CCD or CMOS, and a strobe 31. Has been. The drive circuit 51 controls the above-described mechanism and means connected to the drive circuit 51 by a signal from the control unit.

  The ROM 53 stores a control program for controlling each functional component of the digital camera 32. The RAM 55 stores data necessary for executing the control program.

  The analog signal processing unit 45 performs analog processing on the captured image data and outputs it to the A / D conversion unit 46. The A / D converter 46 converts the captured analog data into digital data. This digital data is output to the digital signal processing means 47. The digital signal processing unit 47 processes digital data. Finally, the digital data is stored in the memory 48.

  The compression / decompression unit 49 performs decompression processing on the image data stored in the memory 48 and the image data stored in the memory card drive 50. The control unit can display the image data after the decompression process on the display 34 via the bus 52. If the user who has seen the image data on the display 34 determines that the image data is unnecessary, the user can delete the image data by operating the operation button 36.

FIG. 3 is an example of a cross-sectional view of the photographic lens barrel.
With reference to FIG. 3, the structure of the taking lens barrel 25 provided in the digital camera 32 will be described. FIG. 3A shows a cross-sectional view of the taking lens barrel 25 in the housed state. FIG. 3B shows a cross-sectional view of the taking lens barrel 25 in the extended state.

  The first lens group 15 is held by first lens group holding means 17. A second lens group 16 is disposed behind the first lens group 15. A photographing lens base means 8 is disposed behind the second lens group 16. A focus lens 18 is disposed behind the imaging lens base unit 8 (on the image sensor side), and an image sensor 24 is provided on the back surface. The image sensor 24 is held by an image sensor holding means 24a.

  Barrier means for protecting the lens of the photographic lens barrel 25 when not in use is provided in front of the optical axis of the first lens group 15 (subject side). The configuration of the barrier means will be described later with reference to FIG. The first lens group holding means 17 is provided with a first moving cam ring 19 on the inner periphery thereof, and is coupled to the straight movement restricting means 20 in a bayonet shape so that it can be integrally rotated. The first lens group holding means 17 is provided with a moving ring 21 on its outer periphery, and is coupled to the first moving cam ring 19 in a bayonet shape so that it can be integrally rotated.

  The moving ring 21 has a second moving cam ring 22 disposed on the outer periphery thereof. A fixed cam ring 23 is further provided on the outer periphery of the moving ring 21. The first lens group holding means 17 can follow a cam groove provided on the outer periphery of the first movable cam ring 19. Further, the second lens group 16 and the photographic lens base means 8 can follow a cam groove provided on the inner periphery of the first movable cam ring 19.

  The moving ring 21 follows the cam groove on the inner periphery of the second moving cam ring 22. The second movable cam ring 22 follows the cam groove on the inner periphery of the fixed cam ring 23. The straight movement restricting means 20 is held straight by a fixed cam ring 23, and all the lens groups other than the focus lens 18 are held straight by the straight movement restricting means 20.

  When the second moving cam ring 22 is rotated by the power generated by the zoom mechanism 41, the second moving cam ring 22 follows the fixed cam ring 23 and further moves out. As the first moving cam ring 19 rotates in conjunction with the rotation of the second moving cam ring 22, the movement of each lens group in the optical axis direction is controlled. The photographic lens base unit 8 is one of the components constituting the image stabilizing lens unit included in the photographic lens barrel 25.

4 to 6 are diagrams illustrating a configuration example of the image stabilizing lens unit.
The anti-vibration lens 1 constituting the anti-vibration lens unit is held by an anti-vibration lens holding unit 2. The anti-vibration lens 1 is driven in a direction perpendicular to the optical axis, thereby correcting a blur (image blur) of a captured image caused by a shake of the imaging device.

  The anti-vibration lens holding means 2 can be coupled to the anti-vibration lens base means 5 which is a base portion. The anti-vibration lens holding means 2 is rotatably held by press-fitting and fixing the guide bar 3 to the anti-vibration lens base means 5.

  An anti-vibration magnet 5 a is integrally fixed to the anti-vibration lens base means 5. A plurality of anti-vibration ball means 12 (three in this example) are installed on the photographic lens base means 8, and the anti-vibration coil means 10 is held at a position facing the anti-vibration magnet. Anti-vibration position detection means 7 is held by the sensor holding means 6.

  As for the configuration on the photographing lens base means 8, the unitized anti-vibration lens base means 5 is installed on the anti-vibration ball means 12. An anti-vibration spring 11 is assembled between the taking lens base means 8 and the anti-vibration lens base means 5 so as to exert an attractive force, and is covered with a sensor holding means 6 so that it cannot be dropped off.

  A toggle spring 4 is installed between the anti-vibration lens holding unit 2 and the anti-vibration lens base unit 5. The toggle spring 4 generates a toggle holding force between the anti-vibration lens holding unit 2 and the anti-vibration lens base unit 5. Instead of the toggle spring 4, an arbitrary spring member that generates an urging force between the anti-vibration lens holding unit 2 and the anti-vibration lens base unit 5 and switches the urging direction from a predetermined position may be applied. Is possible. In the example shown in FIGS. 4A and 4B, the toggle spring 4 applies a clockwise rotational force to the anti-vibration lens holding means 2 and holds it in a shootable state (usage state) substantially coaxial with the optical axis. doing.

  In FIG. 5, the anti-vibration lens holding means 2 is given a counterclockwise rotational force by the toggle spring 4 and is held in a state retracted from the optical axis (retracted state). That is, the anti-vibration lens holding unit 2 has a retracted state of retracting from the optical axis and a use state of entering the optical axis with respect to the photographing lens base unit 8. In the prior art, the torsion spring is used to hold the photographable state, and at the time of retraction, it is retreated by physically contacting with another rotation holding means. By doing so, the anti-vibration lens means 2 always receives the urging force of the torsion spring at the time of retraction, and cannot be moved in the direction orthogonal to the optical axis. In recent years, there has been developed a method for detecting the posture by using the movement of the anti-vibration lens holding means 2 in the direction orthogonal to the optical axis even when the taking lens barrel is housed. Cannot move in a direction perpendicular to the optical axis, so that posture cannot be detected. In the present embodiment, the vibration-proof lens holding means 2 is urged by a toggle spring not only in the use state but also in the retracted state. As a result, the holding by another member is not required, the size can be reduced, and a space in which the vibration-proof lens holding means can move in the direction perpendicular to the optical axis can be secured even in the retracted state.

  Since the anti-vibration lens holding means 2 is urged by a toggle spring, by applying a moving force to the anti-vibration lens holding means 2 in the photographing lens barrel 25, the anti-vibration lens holding means 2 is brought into a retracted state or a use state. Switching means for switching is provided. When the anti-vibration lens 1 is retracted and the anti-vibration lens holding unit 2 is switched to the retracted state, the retraction switching unit 24c included in the image sensor holding unit 24a functions as the first switching unit. At this time, the retraction switching unit 24c applies a moving force in the retraction direction from the optical axis to the anti-vibration lens holding unit 2 until retraction. The anti-vibration lens holding means 2 is switched to the retracted state by this moving force. The toggle spring generates an urging force in a direction opposite to the moving force in the retracting direction from the optical axis until the anti-vibration lens holding means 2 is retracted, but from the predetermined position, the direction of the urging force is the direction of the moving force. Switch to direction. After switching to the retracted state, the connection between the retract switching unit 24c and the anti-vibration lens holding unit 2 is released. After the connection is released, the vibration-proof lens holding means 2 is stably held by the toggle holding force of the toggle spring 4. When the anti-vibration lens 1 is inserted into the optical axis and the anti-vibration lens holding unit is switched to the use state, the barrier anti-vibration switching unit 9a of the barrier driving unit 9 functions as a second switching unit.

FIG. 7 is a diagram showing a configuration example of the barrier means.
Barrier blade means 13 is installed on the upper surface of the barrier drive means 9, and a tension spring 14 is incorporated between the barrier drive means 9 and the barrier blade means 13. The barrier driving means 9 is integrally provided with a barrier switching means 9b, and is rotated by the rotation of the first moving cam ring 19. The barrier blade means 13 is opened or closed by the rotation of the barrier driving means 9.

  When the photographic lens barrel 25 changes from the housed state to the shootable state, the barrier driving means 9 rotates to open the barrier blade means 13. At this time, the anti-vibration lens holding unit 2 is switched from the retracted state to the used state by the rotational force of the barrier driving unit 9. Specifically, the anti-vibration lens holding unit 2 becomes in use as shown in FIG. 4 when the anti-vibration switching unit 9a rotates clockwise in FIG. The anti-vibration lens holding means 2 is stably held by the toggle force of the toggle spring 4 even when in use.

FIG. 8 is a diagram for explaining the movement operation of the image stabilizing lens holding means.
In this embodiment, the anti-vibration lens holding unit 2 changes from the use state to the retracted state as the photographic lens barrel 25 changes from the shootable state to the retracted state. FIG. 8A shows the photographic lens barrel in a shootable state. The anti-vibration lens holding means 2 is in use. The anti-vibration lens holding unit 2 is integrally provided with an anti-vibration lens switching unit 2a. The anti-vibration lens base unit 5 is provided with a holding unit 5a during use and a holding unit 5b during retraction. In the state shown in FIG. 8A, the anti-vibration lens switching means 2a is held in contact with the holding means 5a in use. At this time, the anti-vibration lens holding unit 2 does not contact the barrier driving unit 9. In this state, the anti-vibration lens holding unit 2 is held so as to be operable in a direction orthogonal to the optical axis, and even if the anti-vibration lens holding unit 2 is operated by a moving amount necessary for anti-vibration, the operation is not hindered.

  When the power is turned off, the camera performs a storing operation, and first enters a state shown in FIG. The anti-vibration lens base unit 5 performs the collapsing operation, and the retraction switching unit 24c provided in the image sensor holding unit 24a contacts the anti-vibration lens switching unit 2a. When the anti-vibration lens base unit 5 is further retracted, the retraction switching unit 24c applies a moving force to the anti-vibration lens switching unit 2a, resulting in the state shown in FIG. 8C. In this state, the anti-vibration lens switching unit 2a starts to switch to the retracted state by the retract switching unit 24c. The barrier means is also retracted. Further, when the collapse is advanced, the anti-vibration lens switching means 2 a is switched by the force of the toggle spring 4. As a result, as shown in FIG. 8D, the anti-vibration lens holding means 2 moves to the retracted position, and the anti-vibration lens switching means 2a is held in contact with and held by the retracting holding means 5b. At this time, the barrier switching means 9b provided in the barrier driving means 9 comes into contact with the barrier closing means 24b provided in the image sensor holding means 24a.

  When the camera is further retracted, as shown in FIG. 8E, the photographing lens barrel is retracted, and the vibration-proof lens holding means 2 is retracted and is held by the toggle spring 4. In this state, the barrier driving means 9 is rotated clockwise, for example, and the barrier blade means 13 is closed. In FIG. 8 (E), the barrier driving means 9 is moving in the right direction. The retraction switching unit 24c applies a moving force only in the initial movement of the anti-vibration lens holding unit 2 (FIGS. 8B and 8C), and the lens holding unit switches to the retraction state and is held by the toggle spring 4. When moving (FIG. 8E), no moving force is applied.

  When the power is turned on from the housed state, the barrier means and the anti-vibration lens base means 5 start to extend from the housed state of FIG. As a result, as shown in FIG. 8F, the barrier driving means 9 rotates in a direction to open the barrier blade means 13 (for example, counterclockwise). In FIG. 8F, the barrier driving means 9 has moved leftward. The barrier driving means 9 is provided with a barrier image stabilization switching means 9a. As the barrier driving means 9 moves in the opening direction, the barrier anti-vibration switching means 9a contacts the anti-vibration lens switching means 2a and switches the anti-vibration lens holding means 2 to the use position. Thus, the state transitions from the state shown in FIG. 8F to the state shown in FIG. Further, when the taking lens barrel is extended, the vibration-proof lens holding means 2 is in a use state shown in FIG. 8 (H) and is held by the toggle spring 4. The barrier anti-vibration switching unit 9a applies a moving force only at the initial movement of the anti-vibration lens holding unit 2 (FIG. 8F), and the anti-vibration lens holding unit 2 switches to the use state and is held by the toggle spring 4. When moving (FIG. 8H), no moving force is applied.

  The anti-vibration lens holding means 2 needs to move in a direction orthogonal to the optical axis within a range larger than the correction amount necessary for anti-vibration when in use. In the present embodiment, in the use state of FIGS. 8A and 8H, the anti-vibration lens holding unit 2 does not come into contact with other members even if it moves in the direction orthogonal to the optical axis. The anti-vibration lens holding means 2 is similarly held in a retracted state so as to be movable in a direction perpendicular to the optical axis. As a result, the anti-vibration lens can be operated even when the taking lens barrel 25 is stored. Therefore, for example, the anti-vibration lens can be used as a member having functions of posture detection and a level. In order to realize the posture detection and the function of the level, the movement amount of the anti-vibration lens holding unit 2 may be smaller than the movement amount in the use state.

  With the above configuration, the retractable lens (anti-vibration lens) can be held without applying an extra external force even during the retracting. Thereby, there is no load on the retreat switching means 24b, and deformation is prevented. Further, since the retractable lens can be moved in the direction orthogonal to the optical axis even during retraction, it can be used for posture detection.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to this embodiment, A various deformation | transformation and change are possible within the range of the summary. In the present embodiment, the operation of the image stabilizing lens holding unit 2 in the photographing lens barrel 25 provided in the digital camera 32 has been described as an example. However, the scope of application of the present invention is limited to an imaging apparatus such as the digital camera 32. Not. The present invention can be applied to any optical apparatus.

2 Anti-vibration lens holding means 4 Toggle spring 32 Digital camera

Claims (8)

A base part;
A lens holding means for holding the lens and having a retracted state of retracting from the optical axis with respect to the base portion and a use state of entering the optical axis;
A spring member that generates an urging force between the base portion and the lens holding means, and the urging direction is switched from a predetermined position;
Switching means for switching the lens holding means to the retracted state or the use state by applying a moving force to the lens holding means;
An image sensor holding means for holding the image sensor provided on the image sensor side from the base portion;
Barrier means provided on the subject side from the base portion and protecting the lens barrel ;
The spring member biases and holds the lens holding means in the retracted state and the use state,
The switching means applies the moving force only when the lens holding means is moved, and applies the moving force when the lens holding means is switched to the retracted state or the use state and is held by the spring member. Without
The lens barrel characterized in that the switching means includes a first switching means provided in the image sensor holding means and a second switching means provided in the barrier means. The first switching means applies a moving force for switching the lens holding means from the use state to the retracted state to the lens holding means. The second switching means removes the lens holding means from the retracted state. The lens barrel according to claim 1, wherein a moving force for switching to the use state is applied to the lens holding unit. The lens barrel according to claim 1, wherein the lens holding unit is held so as to be operable in a direction orthogonal to the optical axis in the retracted state and the used state. 4. The lens mirror according to claim 1, wherein the spring member is a toggle spring, and holds the lens holding unit with a toggle holding force in the retracted state and the used state. 5. Tube. The lens is an anti-vibration lens;
The lens barrel according to any one of claims 1 to 4, wherein the lens holding means is used for posture detection of the lens barrel. The state of the lens holding unit is changed from the use state to the retracted state as the lens barrel changes from the shootable state to the retracted state. The lens barrel described in 1.   An optical apparatus comprising the lens barrel according to any one of claims 1 to 6.   An imaging device comprising the lens barrel according to any one of claims 1 to 6.