Lens device and imaging device having the same

Abstract

To provide a lens device that can improve user operability. [Solution] The lens device includes a first optical system including a first lens that moves during focusing, a second optical system including a second lens that moves during focusing, and control means for moving the first and second lenses in a first mode and for moving one of the first and second lenses in a second mode, wherein the optical axes of the first and second optical systems do not coincide with each other, and the control means moves the one lens at a second timing using position information relating to the position of the one lens after it has been moved at a first timing in the second mode.

Description

Technical Field

[0001] The present invention relates to a lens device and an imaging device having the same.

Background Art

[0002] Conventionally, in a lens device that forms an image of an object on one imaging element by each of two optical systems, a configuration in which the relative positions of the two optical systems can be adjusted is known (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such a lens device, the relative positional relationship between the two optical systems may not be maintained due to an external impact or the like. In that case, it is necessary to adjust the relative positional relationship between the two optical systems, and the operability of the user may be impaired.

[0005] An object of the present invention is to provide a lens device capable of improving the operability of a user.

Means for Solving the Problems

[0006] A lens device as one aspect of the present invention comprises a first optical system including a first lens that moves during focusing, a second optical system including a second lens that moves during focusing, and a control means for moving the first and second lenses in a first mode and for moving one of the first and second lenses in a second mode, wherein the optical axes of the first and second optical systems do not coincide with each other, and the control means is characterized in that, in the second mode, it uses position information relating to the position of the one lens after it has been moved at a first timing to move the one lens at a second timing. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a lens device that can improve user operability. [Brief explanation of the drawing]

[0008] [Figure 1] This is a diagram illustrating the configuration of a lens-interchangeable camera according to an embodiment of the present invention. [Figure 2] This is a flowchart showing the method for storing location information in Example 1. [Figure 3] This flowchart shows the control of the focus lens during startup operation in Example 1. [Figure 4] This flowchart shows the control of the focus lens during startup operation in Example 2. [Figure 5] This is a flowchart showing the method for storing location information in Example 3. [Figure 6] This is a flowchart showing the location information update process in Example 3. [Figure 7] This is a flowchart showing the method for storing location information in Example 4. [Figure 8] This is a flowchart showing the memory area determination process in Example 4. [Figure 9] This is a flowchart showing the control of the focus lens during the recovery operation in Example 4. [Modes for carrying out the invention]

[0009] The embodiments of the present invention will be described in detail below with reference to the drawings. In each figure, the same reference numeral is used for identical components, and redundant explanations are omitted.

[0010] Figure 1 is a diagram showing the configuration of an interchangeable lens camera according to an embodiment of the present invention. The interchangeable lens camera consists of a lens device 100 and an imaging device 200 to which the lens device 100 can be attached or detached. The lens device 100 and the imaging device 200 are mechanically and electrically connected via a mount (not shown), and power is supplied and communication is performed via terminals provided on the mount.

[0011] The lens device 100 has a first optical system 101L and a second optical system 101R arranged in parallel with the first optical system 101L. That is, the optical axes of the first optical system 101L and the second optical system 101R do not coincide with each other. Note that the optical axes of the two optical systems may be parallel or non-parallel. The first optical system 101L and the second optical system 101R each form an optical image of the subject on the image sensor 201 of the imaging device 200. The first optical system 101L includes an aperture (not shown) and a focus lens (first lens) 104L that moves during focusing. The second optical system 101R includes an aperture (not shown) and a focus lens (second lens) 104R that moves during focusing. The aperture has aperture blades, and the amount of light is adjusted by moving the aperture blades with an actuator. Note that the focus lenses 104R and 104L may each be composed of one lens or multiple lenses.

[0012] The lens device 100 has a mode switching switch (not shown) and is configured to switch between a shooting mode (first mode) and an adjustment mode (second mode). In shooting mode, the focus adjustment for the subject by the imaging device 200 is performed by the focus lens 104L. The lens device 100 moves the focus lenses 104R and 104L together to capture a stereoscopic image. In adjustment mode, the lens control unit 106 moves only the focus lens 104R, thereby adjusting the relative position of the focus lens 104R to the focus lens 104L. This allows the position of the focus lens 104R to be adjusted to a position that does not affect the image capture.

[0013] The lens control unit 106 functions as a control means, reading and executing a program stored in the memory 112. The lens control unit 106 communicates with the camera control unit 207. The lens control unit 106 receives drive command values ​​for the aperture and focus lens 104L from the camera control unit 207 and generates drive commands for the aperture and focus lens 104L. The lens control unit 106 also transmits information about the lens device 100 requested by the camera control unit 207 and acquires information transmitted by the camera control unit 207.

[0014] The lens control unit 106 generates signals to drive the actuators 110R and 110L, and uses these signals to drive the actuators 110R and 110L via the focus drive unit 107, thereby moving the focus lenses 104R and 104L. In this embodiment, stepping motors are used as actuators.

[0015] In the shooting mode, the lens control unit 106 drives the actuator 110L to integrally move the focus lenses 104R and 104L. In the adjustment mode, the lens control unit 106 drives the actuator 110R to move only the focus lens 104R. That is, in the shooting mode, the two focus lenses move simultaneously, and in the adjustment mode, one focus lens moves so that the relative position with respect to the other focus lens changes. Also, in the present embodiment, the actuator 110R moves the focus lens 104R, and the actuator 110L integrally moves the focus lenses 104R and 104L, but the present invention is not limited thereto. The actuators 110R and 110L may be configured to move the focus lenses 104R and 104L, respectively. At this time, in the shooting mode, the actuators 110R and 110L may be driven so that the focus lenses 104R and 104L move simultaneously.

[0016] The focus lens 104L moves in the optical axis direction by the lens control unit 106 during the shooting mode to perform focus adjustment on the subject. The focus lens 104R moves in the optical axis direction by the lens control unit 106 during the adjustment mode. Thereby, the relative position of the focus lens 104R with respect to the focus lens 104L is adjusted.

[0017] The focus position origin detection unit 111R is composed of a photo interrupter and outputs a detection signal to the lens control unit 106. As the focus lens 104R moves, the light shielding plate moves and the output level of the detection signal changes. The lens control unit 106 determines the origin position serving as a reference for position control of the focus lens 104R using the change in the output level. The origin position may be determined, for example, at the time of startup of the imaging device 200 or the like. Specifically, the lens control unit 106 moves the focus lens 104R, detects the change in the signal of the focus position origin detection unit 111R, and determines the origin position using the change.

[0018] The focus position origin detection unit 111L has the same configuration as the focus position origin detection unit 111R. The lens control unit 106 determines the origin position serving as a reference for position control of the focus lens 104L using the same method as the method for determining the origin position of the focus lens 104R.

[0019] The memory 112 is a storage means composed of a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. Information stored in the memory 112 is, for example, information regarding the position of the focus lens 104L and the subject distance. Further, information necessary for the operation of the lens device 100 and information regarding the lens device 100 to be transmitted to the imaging device 200 are stored.

[0020] Also, the lens device 100 has a manual operation unit as an operation member that can manually operate the moving amounts of the focus lenses 104R and 104L.

[0021] The imaging device 200 includes an imaging element 201, a signal processing unit 202, a recording processing unit 203, an electronic viewfinder 204, a display unit 205, a defocus detection unit 206, a camera control unit 207, and a memory 208.

[0022] The imaging element 201 photoelectrically converts the light from the first optical system 101L and the second optical system 101R to generate an electrical signal and transmits it to the signal processing unit 202. The imaging element 201 includes, in addition to imaging pixels, focus detection pixels (not shown).

[0023] The signal processing unit 202 converts the electrical signal from the imaging element 201 into a digital signal. Further, the signal processing unit 202 performs various image processes such as noise removal and color correction on the digital signal and transmits the image data to the recording processing unit 203.

[0024] The recording processing unit 203 displays the input image data on the electronic viewfinder 204 and the display unit 205. The defocus detection unit 206 detects the phase difference between the signals of a pair of subject images obtained by light incident on the focus detection pixels of the image sensor 201 via a microlens that performs pupil division. The defocus detection unit 206 determines the amount of defocus based on the detected phase difference and outputs it to the camera control unit 207.

[0025] The camera control unit 207 is a computing unit equipped with a CPU and is electrically connected to the recording processing unit 203, the defocus detection unit 206, and the memory 208. The camera control unit 207 reads and executes programs recorded in the memory 208 and communicates information necessary for autofocus control with the lens control unit 106. The camera control unit 207 also controls the imaging device 200 in response to inputs from the camera operation unit, such as a shooting switch and various setting switches (not shown).

[0026] Memory 208 holds information necessary for operation.

[0027] The lens device 100 is connected to the imaging device 200 and performs startup operations in conjunction with the startup of the imaging device 200. During the startup operations, the origin position of the focus lens 104R is determined, and then the focus lens 104R is moved to the target position.

[0028] Here, the setting of the adjustment position of the focus lens 104R and its startup operation will be described. In adjustment mode, the focus lens 104R is moved by the manual operation unit, and the position information regarding the adjustment position after the focus lens 104R has moved is stored in the memory 112. As a startup operation, the lens control unit 106 issues a drive command based on the position information stored in the memory 112. After the origin position is determined, the focus lens 104R moves to the adjustment position, which is the target position. In this embodiment, the position information is stored in the memory 112, but it may also be stored in a storage means provided in other devices such as the imaging device 200 or a server. Furthermore, the position information may be information regarding the absolute position of the focus lens 104R with respect to the origin position, or it may be information that shows the relative relationship with the position of the focus lens 104L.

[0029] The following describes the control for moving the focus lens 104R to the adjustment position in each embodiment. [Examples]

[0030] Figure 2 is a flowchart showing the method for storing position information related to the adjustment position in this embodiment. This flow is initiated when the system is switched to adjustment mode using the mode switching switch.

[0031] In step S201, the lens control unit 106 acquires the operation amount for the manual operation unit.

[0032] In step S202, the lens control unit 106 calculates the amount of movement according to the operation amount acquired in step S202, and moves the focus lens 104R based on the calculated amount of movement.

[0033] In step S203, the lens control unit 106 determines whether the mode has been switched from adjustment mode to shooting mode using the mode switch. If the lens control unit 106 determines that the mode has been switched to shooting mode, it executes the process in step S204; otherwise, it executes the process in step S201.

[0034] In step S204, the lens control unit 106 stores the current position of the focus lens 104R as the adjustment position and stores position information related to the adjustment position in the memory 112.

[0035] Figure 3 is a flowchart showing the control of the focus lens 104R during startup in this embodiment. This flow begins when power is supplied to the lens device 100.

[0036] In step S301, the lens control unit 106 acquires position information regarding the adjustment position of the focus lens 104R stored in the memory 112.

[0037] In step S302, the lens control unit 106 moves the focus lens 104R in a direction that changes the output level of the detection signal from the focus position origin detection unit 111R.

[0038] In step S303, the lens control unit 106 determines whether it has detected the origin position based on the detection signal from the focus position origin detection unit 111R. If the lens control unit 106 determines that it has detected the origin position, it executes the process in step S304; otherwise, it continues the process in this step.

[0039] In step S304, the lens control unit 106 moves the focus lens 104R to the adjustment position, which is the target position, based on the position information acquired in step S301.

[0040] As described above, in this embodiment, the adjustment position of the focus lens 104R is stored in the memory 112, and the focus lens 104R is moved to the stored adjustment position during startup. This reduces the frequency of adjustments required by the user.

[0041] In this embodiment, the focus lens 104R is moved to the adjustment position during startup, but the present invention is not limited to this. For example, the focus lens 104R may be moved to the adjustment position at a timing desired by the user, such as during the recovery operation when the actuator loses step (the timing when a signal corresponding to the user's operation is received). [Examples]

[0042] In this embodiment, when position information relating to the adjustment positions of multiple different focus lenses 104R is stored in the memory 112, a method for moving the focus lens 104R to the adjustment position using one position information selected from the multiple position information will be described.

[0043] Memory 112 stores not only information about the adjustable position (second position information) described in Embodiment 1, but also initial information (first position information) about a fixed initial position, such as the factory-set adjustment position or the design position. The user can instruct not only normal movement, which moves the focus lens 104R based on the second position information, but also initial position movement, which moves the focus lens 104R to its initial position, using an operating member mounted on the lens device 100. In this case, it is determined whether to perform the initial position movement or normal movement by determining whether a signal instructing the initial position movement has been received.

[0044] Furthermore, the initial position may be used not only in response to user operations, but also, for example, when the adjustment position is outside the movement range of the focus lens 104R. In this case, it is sufficient to determine whether the position information is normal information, indicating that the adjustment position is normal. If the position information is normal information, the startup operation should be performed with the adjustment position as the target position. If the position information is not normal information, i.e., if the adjustment position is abnormal information, the startup operation should be performed with the initial position as the target position.

[0045] Furthermore, if the position information is abnormal, such as the adjustment position being outside the movement range of the focus lens 104R as described above, the memory 112 may be configured not to retain it.

[0046] Figure 4 is a flowchart showing the control of the focus lens 104R during startup operation in this embodiment.

[0047] In step S401, the lens control unit 106 determines whether it has received a signal instructing the initial position movement. If the lens control unit 106 determines that it has received a signal instructing the initial position movement, it executes the process in step S402; otherwise, it executes the process in step S403.

[0048] In step S402, the lens control unit 106 acquires second position information from the memory 112.

[0049] In step S403, the lens control unit 106 acquires first position information from the memory 112.

[0050] In step S404, the lens control unit 106 moves the focus lens 104R in a direction that changes the output level of the detection signal from the focus position origin detection unit 111R.

[0051] In step S405, the lens control unit 106 determines whether the origin position has been detected based on the detection signal from the focus position origin detection unit 111R. If the lens control unit 106 determines that the origin position has been detected, it executes the process in step S406; otherwise, it continues the process in this step.

[0052] In step S406, the lens control unit 106 moves the focus lens 104R to the adjustment position, which is the target position, based on the position information acquired in step S402 or step S403. [Examples]

[0053] This embodiment describes a method for determining whether to store newly acquired position information in memory 112 based on situational information regarding the circumstances under which position information is acquired in a pre-stored adjustment mode. Situational information includes, for example, information regarding the amount of defocus during adjustment mode and information regarding the depth of focus (information regarding the aperture value and the allowable circle of confusion diameter). In this embodiment, the case in which the aperture value used when acquiring position information is stored as situational information is described. The allowable circle of confusion diameter is the smallest size that the image sensor cannot recognize as blur.

[0054] Figure 5 is a flowchart showing the method for storing position information related to the adjustment position in this embodiment. This flow is started when the system switches to adjustment mode using the mode switching switch.

[0055] The processes in steps S501 to S503 are the same as those in steps S201 to S203, respectively, so their explanation will be omitted.

[0056] In step S504, the lens control unit 106 performs a position information update process.

[0057] Figure 6 is a flowchart showing the location information update process in this embodiment.

[0058] In step S601, the lens control unit 106 obtains the aperture value from the memory 112 as position information (third position information) relating to the adjustment position of the focus lens 104R, and as status information (first status information) relating to the circumstances when acquiring the position information.

[0059] In step S602, the lens control unit 106 acquires the current aperture value as position information (fourth position information) regarding the current position of the focus lens, and as status information (second status information) regarding the circumstances under which the current position information was acquired.

[0060] In step S603, the lens control unit 106 determines whether the aperture value obtained in step S601 is greater than the aperture value obtained in step S602. For the same allowable circle of confusion diameter, a smaller aperture value results in a shallower depth of field and higher accuracy of positional information. If the lens control unit 106 determines that the aperture value obtained in step S601 is greater than the aperture value obtained in step S602, it executes the process in step S604. If the lens control unit 106 determines that the aperture value obtained in step S601 is smaller than the aperture value obtained in step S602, it terminates this flow. Note that if the aperture value obtained in step S601 is equal to the aperture value obtained in step S602, it is possible to arbitrarily set which step to proceed to.

[0061] In step S604, the lens control unit 106 updates the position information and aperture value stored in the memory 112 to the current position information and aperture value.

[0062] Note that the situational information may not be limited to the aperture value. For example, it may be the allowable circle of confusion diameter or the defocus amount of the focus lens 104R obtained from the imaging device 200. Alternatively, it may be the defocus amounts of the focus lenses 104R and 104L obtained from the imaging device 200, or the difference between the two defocus amounts.

[0063] As explained above, by referring to situational information and determining when to update positional information in adjustment mode, the positional information can be updated to more reliable information. In other words, by referring to situational information, the position of the focus lens 104R can be adjusted to a position that has less impact on shooting. In addition, the relative positional difference between the focus lenses 104R and 104L can be reduced. [Examples]

[0064] When the EV value (exposure value) during shooting is small, the reliability of the defocus amount acquired by the imaging device 200 may be low. In this embodiment, a case is described in which a different position information is stored in addition to the position information used during normal shooting, depending on the EV value.

[0065] Figure 7 is a flowchart showing the method for storing position information related to the adjustment position in this embodiment. This flow is started when the system switches to adjustment mode using the mode switching switch.

[0066] The processes in steps S701 to S703 are the same as those in steps S201 to S203, respectively, so their explanation is omitted.

[0067] In step S704, the lens control unit 106 performs a memory area determination process to determine which memory area of ​​the memory 112 to store the adjustment position.

[0068] In step S705, the lens control unit 106 stores the position information in the memory 112 in the memory area determined in step S704.

[0069] Figure 8 is a flowchart showing the memory area determination process in this embodiment.

[0070] In step S801, the lens control unit 106 acquires information regarding the EV value from the imaging device 200.

[0071] In step S802, the lens control unit 106 determines whether the EV value obtained in step S801 is less than a threshold stored in memory 112. If the lens control unit 106 determines that the EV value is less than the threshold, it executes the process in step S803; if it determines that the EV value is greater than the threshold, it executes the process in step S804. Note that if the EV value is equal to the threshold, the process to proceed to can be arbitrarily set.

[0072] In step S803, the lens control unit 106 determines a separate storage area, different from the normal storage area, to be used as the storage area.

[0073] In step S804, the lens control unit 106 determines the normal storage area as the storage area.

[0074] Figure 9 is a flowchart showing the control of the focus lens 104 during the recovery operation of this embodiment. During the recovery operation, for example, during shooting mode, the step-out state of the actuator 110R is detected, and an operation equivalent to the startup operation is performed.

[0075] In step S900, the lens control unit 106 determines a storage area for position information related to the adjustment position that will be the target position for the recovery operation, based on the EV value information at the time of step loss.

[0076] Since the processing in steps S901 to S904 is the same as the processing in steps S301 to S304, the explanation will be omitted.

[0077] In this embodiment, the memory area was determined based on the EV value as state information regarding the state in adjustment mode, but the memory area may also be determined based on the reliability of the defocus amount. In this case, if the reliability is low, a different memory area from the normal memory area should be determined as the memory area, and if the reliability is high, the normal memory area should be determined as the memory area.

[0078] This embodiment includes the following configuration. (Composition 1) A first optical system including a first lens that moves during focusing, A second optical system including a second lens that moves during focusing, The system includes control means for moving the first and second lenses in a first mode, and for moving one of the first and second lenses in a second mode. The optical axes of the first and second optical systems do not coincide with each other. The lens device is characterized in that the control means moves the one lens at a second timing using position information relating to the position of the one lens after it has been moved at a first timing in the second mode. (Configuration 2) The lens device according to configuration 1, further comprising a storage means for storing the aforementioned position information. (Composition 3) The lens apparatus according to configuration 1 or 2, characterized in that the position information is information relating to the relative position of one lens to the other lens of the first and second lenses. (Composition 4) The lens device according to any one of configurations 1 to 3, characterized in that the control means moves one of the lenses based on position information selected from a plurality of mutually different position information. (Composition 5) The lens device according to configuration 4, characterized in that the plurality of positional information includes a first positional information which is fixed initial information and a second positional information which is set to be changeable. (Composition 6) The lens device according to configuration 5, characterized in that the second position information is stored when the system switches from the second mode to the first mode. (Composition 7) The lens device according to configuration 5 or 6, characterized in that when the control means determines that the second position information is abnormal information, it moves the one lens using the first position information. (Composition 8) The lens device according to any one of configurations 5 to 7, characterized in that the second position information is not stored if it is determined to be abnormal information. (Composition 9) A lens device according to any one of configurations 1 to 8, characterized in that the aforementioned location information and situational information relating to the circumstances under which the location information is acquired are stored. (Composition 10) The lens device according to configuration 9, characterized in that the aforementioned situation information includes the aperture value of the optical system including the one lens. (Composition 11) The lens device according to configuration 9 or 10, characterized in that the aforementioned situation information includes the amount of defocus of the one lens. (Composition 12) The lens device according to any one of the configurations 9 to 11, characterized in that the aforementioned situation information includes the defocus amount of the first and second lenses. (Composition 13) The lens device according to any one of the configurations 9 to 12, characterized in that the aforementioned situation information includes the difference in the amount of defocus of the first and second lenses. (Composition 14) The lens device according to any one of configurations 9 to 13, characterized in that the aforementioned situation information includes the allowable circle of confusion diameter. (Composition 15) The lens device according to any one of configurations 9 to 14, characterized in that, when the control means has stored a third position information as position information and a first situation information relating to the circumstances when acquiring the third position information, it acquires a fourth position information relating to the current position of one of the lenses and a second situation information relating to the circumstances when acquiring the fourth position information, and determines whether to update the third position information to the fourth position information based on the first and second situation information. (Composition 16) The lens device according to any one of configurations 1 to 15, characterized in that, when the fifth position information as position information is stored in the first storage area, the control means determines whether to store a sixth position information different from the fifth position information in a second storage area different from the first storage area, based on state information relating to the state in the second mode. (Composition 17) The lens device according to configuration 16, characterized in that the state information includes an exposure value. (Composition 18) The lens device according to configuration 16 or 17, characterized in that the state information includes the reliability of the defocus amount. (Composition 19) The lens device according to any one of configurations 1 to 18, characterized in that the control means moves the second lens using the position information when the lens device is activated. (Composition 20) The lens device according to any one of configurations 1 to 19, characterized in that the control means moves the second lens using the position information when it receives a signal corresponding to a user operation different from the switching signal to the second mode. (Composition 21) A lens device described in any one of configurations 1 to 20, An imaging device characterized by having an image sensor.

[0079] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its gist. [Explanation of Symbols]

[0080] 100 Lens device 101L First Optical System 101R Second Optical System 104L Focusing Lens (First Lens) 104R Focus Lens (Second Lens) 106 NS Control Unit (Control Means)

Claims

1. A first optical system including a first lens that moves during focusing, A second optical system including a second lens that moves during focusing, The system includes control means for moving the first and second lenses in a first mode, and for moving one of the first and second lenses in a second mode. The optical axes of the first and second optical systems do not coincide with each other. The lens device is characterized in that the control means moves the one lens at a second timing using position information relating to the position of the one lens after it has been moved at a first timing in the second mode.

2. The lens device according to claim 1, further comprising a storage means for storing the position information.

3. The lens apparatus according to claim 1 or 2, characterized in that the position information is information relating to the relative position of one of the first and second lenses with respect to the other lens.

4. The lens device according to claim 1 or 2, characterized in that the control means moves one of the lenses based on position information selected from a plurality of mutually different position information.

5. The lens device according to claim 4, characterized in that the plurality of positional information includes a first positional information which is fixed initial information and a second positional information which is set to be changeable.

6. The lens device according to claim 5, characterized in that the second position information is stored when the device is switched from the second mode to the first mode.

7. The lens device according to claim 5, characterized in that when the control means determines that the second position information is abnormal information, it moves one of the lenses using the first position information.

8. The lens device according to claim 5, characterized in that the second position information is not stored if it is determined to be abnormal information.

9. The lens device according to claim 1 or 2, characterized in that it stores the aforementioned location information and situational information relating to the circumstances under which the aforementioned location information is acquired.

10. The lens device according to claim 9, characterized in that the aforementioned situation information includes the aperture value of the optical system including the one lens.

11. The lens apparatus according to claim 9, characterized in that the aforementioned situation information includes the amount of defocus of the one lens.

12. The lens apparatus according to claim 9, characterized in that the aforementioned situational information includes the defocus amounts of the first and second lenses.

13. The lens apparatus according to claim 9, characterized in that the status information includes the difference in the amount of defocus of the first and second lenses.

14. The lens device according to claim 9, characterized in that the aforementioned situation information includes the allowable circle of confusion diameter.

15. The lens device according to claim 9, wherein the control means, when a third position information as position information and a first situation information relating to the circumstances when acquiring the third position information are stored, acquires a fourth position information relating to the current position of one of the lenses and a second situation information relating to the circumstances when acquiring the fourth position information, determines whether to update the third position information to the fourth position information based on the first and second situation information.

16. The lens device according to claim 1 or 2, characterized in that, when the fifth position information as position information is stored in the first storage area, the control means determines, based on state information relating to the state in the second mode, whether to store a sixth position information different from the fifth position information in a second storage area different from the first storage area.

17. The lens device according to claim 16, characterized in that the aforementioned state information includes an exposure value.

18. The lens device according to claim 16, characterized in that the aforementioned state information includes the reliability of the defocus amount.

19. The lens device according to claim 1 or 2, characterized in that the control means moves the second lens using the position information when the lens device is activated.

20. The lens device according to claim 1 or 2, characterized in that the control means moves the second lens using the position information when it receives a signal corresponding to a user operation different from the switching signal to the second mode.

21. A lens device according to claim 1 or 2, An imaging device characterized by having an image sensor.

Images