JP7497161B2 - CONTROL DEVICE, LENS DEVICE, AND IMAGING DEVICE - Google Patents

Description

The present invention relates to a control device capable of adjusting a focus by driving a focus lens.

Autofocus (AF) and manual focus (MF) are known methods for adjusting the focus by driving a focus lens. AF is a method for adjusting the focus by calculating the in-focus position of the focus lens based on an AF evaluation value generated by an AF sensor. MF is a method for adjusting the focus by the user manually operating the focus ring.

Zoom tracking control is also known, which maintains a focused state by driving a focus lens to correct image plane fluctuations that occur when a zoom lens is driven. Patent Document 1 discloses a method of switching area modes based on electronic cam (tracking curve) information that indicates the relationship between the zoom lens position and the focus lens position that maintains a focused state during zooming.

Japanese Patent No. 5843442

However, in the method disclosed in Patent Document 1, the area mode may be switched unintentionally by the user during zoom tracking control by the user's zoom operation. Here, the area mode includes an AF possible area where focus adjustment is possible with both AF and MF, and a mode related to an MF-only area where focus adjustment is possible only with MF. In the MF-only area, it is possible to drive the focus lens and obtain an image from the imaging sensor, but AF cannot be performed due to restrictions such as the incident angle of the light entering the AF sensor.

If driving from the AF-enabled area to the MF-only area by operations other than MF operations is restricted in order to avoid the area mode being switched and forcibly changed to the MF state by operations other than MF operations, the subject distance cannot be maintained. On the other hand, if the user intentionally sets the MF state, even if the AF-enabled area is switched to the MF-only area, the MF state will not change, so it is preferable to maintain the subject distance rather than maintaining the AF-enabled area.

Therefore, an object of the present invention is to provide a control device, a lens device, and an imaging device that can reflect the user's intentions, prevent switching from an AF-enabled area to an MF-only area due to reasons other than MF operation , and improve user operability.

A control device as one aspect of the present invention has a first control means for automatically adjusting a focus lens to a focused position, a second control means for adjusting the focus lens based on an amount of operation by a user, a third control means for driving the focus lens, and a setting means for switchably setting a first control by the first control means and a second control by the second control means, wherein the first control means and the second control means are effective in a first driving range of the focus lens, the first control means is ineffective in a second driving range of the focus lens, the second control means is effective in the second driving range, and when the second control is set by the setting means, when the focus lens is located in the first driving range and the second driving range changes so that the position of the focus lens is included in the second driving range when a subject distance is maintained, or when the focus lens is located in the second driving range and the second driving range changes so that the position of the focus lens is included in the first driving range when a subject distance is maintained, the third control means drives the focus lens to maintain the subject distance before and after the change in the second driving range .

Other objects and features of the present invention are described in the following examples.

According to the present invention, it is possible to provide a control device, a lens device, and an imaging device that can reflect the user's intentions, prevent switching from an AF-enabled area to an MF-only area other than by MF operation, and improve user operability .

FIG. 2 is a block diagram of an imaging device in each embodiment. FIG. 11 is a diagram showing electronic cam data for each subject distance in each embodiment. FIG. 4 is a diagram showing an AF possible area and an MF exclusive area in each embodiment. 5 is a diagram showing the relationship between the zoom lens position and the minimum shooting distance in the first embodiment. FIG. 4 is a flowchart of a control method in the first embodiment. FIG. 4 is an explanatory diagram of a control method in the first embodiment. FIG. 4 is an explanatory diagram of a control method in the first embodiment. FIG. 4 is an explanatory diagram of a control method in the first embodiment. FIG. 4 is an explanatory diagram of a control method in the first embodiment. FIG. 11 is a diagram showing the relationship between the aperture value and the minimum shooting distance in Example 2. 10 is a flowchart of a control method in the second embodiment. FIG. 11 is an explanatory diagram of a control method in the second embodiment. FIG. 11 is an explanatory diagram of a control method in the second embodiment. FIG. 11 is an explanatory diagram of a control method in the second embodiment. FIG. 11 is an explanatory diagram of a control method in the second embodiment.

The following describes in detail an embodiment of the present invention with reference to the drawings.

First, the configuration of the imaging device in each embodiment will be described. FIG. 1 is a block diagram of an imaging device 10. The imaging device 10 is configured with a camera body (imaging device body) 200 and an interchangeable lens (lens device) 100 that is detachable from the camera body 200. However, the imaging devices in each embodiment are not limited to this, and the camera body and lens device may be configured as an integrated unit.

The interchangeable lens 100 is mechanically and electrically connected to the camera body 200 via a mount (not shown). The interchangeable lens 100 receives power from the camera body 200 via a power supply terminal (not shown) provided on the mount described above. The interchangeable lens 100 uses the power received from the camera body 200 to control various actuators and a lens microcomputer 111 (described below). The camera body 200 communicates with the interchangeable lens 100 via a communication terminal (not shown) provided on the mount described above, and controls the interchangeable lens 100 by sending control commands to the interchangeable lens 100.

The camera body 200 has an image sensor 201 with a phase difference AF sensor function, a signal processing circuit 202, a recording processing unit 203, a display unit 204, an operation unit 205, and a camera microcomputer 206. The image sensor 201 has a CMOS sensor or a CCD sensor, and performs photoelectric conversion on a subject image (optical image) formed by the imaging optical system in the interchangeable lens 100 to output an electrical signal (analog signal). The analog signal output from the image sensor 201 is converted into a digital signal by an A/D conversion circuit (not shown).

The signal processing circuit 202 performs various image processing on the digital signal from the A/D conversion circuit to generate a video signal. The signal processing circuit 202 also generates from the video signal the contrast state of the subject image, i.e., focus information indicating the focus state of the imaging optical system and luminance information indicating the exposure state. The signal processing circuit 202 also outputs the video signal to the display unit 204, which displays the video signal as a live view image used to check the composition, focus state, etc. The signal processing circuit 202 also outputs the video signal to the recording processing unit 203. The recording processing unit 203 stores the video signal in an external memory or the like as still images or moving image data.

The camera microcomputer 206, which serves as a camera control unit, controls the camera body 200 in response to input from an image capture command switch and various setting switches included in the operation unit 205. The camera microcomputer 206 also transmits control commands to the lens microcomputer 111 via the camera communication unit, related to the light amount adjustment operation of the aperture unit 103 in response to brightness information and the focus adjustment operation of the focus lens 105 in response to focus information.

The interchangeable lens 100 has an imaging optical system, various control units that control the actuators that drive the imaging optical system, an operation ring 110 for operating the focus lens 105, a focus mode switch 112, and a lens microcomputer 111.

The lens microcomputer 111 is a lens control unit (control device) that controls the operation of each unit within the interchangeable lens 100. The lens microcomputer 111 receives control commands transmitted from the camera body 200 via the communication unit, and receives a request to transmit lens data. The lens microcomputer 111 also performs lens control corresponding to the control command, and transmits lens data corresponding to the transmission request to the camera body 200. The lens microcomputer 111 also transmits the focus mode selected by the user to the camera body 200 via the focus mode switch 112.

The lens microcomputer 111 also outputs commands to the aperture control unit 107 and focus lens control unit 109 in response to control commands related to light amount adjustment and focusing. The aperture control unit 107 and focus lens control unit 109 drive the aperture unit 103 and focus lens 105, respectively, in accordance with commands from the lens microcomputer 111. This enables light amount adjustment processing by the aperture unit 103 and focus lens 105, and autofocus processing that controls focus adjustment operation. The lens microcomputer 111 also outputs commands to the focus lens control unit 109 to drive the focus lens 105 and control focus adjustment operation according to the amount of operation of the operation ring 110, depending on the amount of operation of the operation ring 110.

In each embodiment, the lens microcomputer 111 has a first control means 111a, a second control means 111b, a third control means 111c, and a setting means 111d. The first control means 111a automatically adjusts the focus lens 105 to a focus position (i.e., the first control means 111a has a function of realizing AF control). The second control means 111b manually adjusts the focus lens 105 (based on the amount of operation by the user) (i.e., the second control means 111b has a function of realizing MF control). The third control means 111c drives the focus lens 105 (zoom tracking control, etc.). The setting means 111d acquires a signal from the focus mode switch 112 and sets the first control (AF control) by the first control means 111a and the second control (MF control) by the second control means 111b to be switchable.

As described below, the third control means 111c controls the focus lens 105 when the first driving area (AF possible area) of the focus lens 105 or the second driving area (MF only area) of the focus lens 105 changes. In other words, the third control means 111c has a function of driving or stopping the focus lens 105 so as to position the focus lens 105 at an appropriate position when the AF possible area or MF only area of the focus lens 105 changes.

In this embodiment, an example has been described in which the lens microcomputer 111 has a first control means 111a, a second control means 111b, and a third control means 111c. This can be considered equivalent to the lens microcomputer 111 having a function corresponding to the function of the first control means 111a, a function corresponding to the function of the second control means 111b, and a function corresponding to the function of the third control means 111c.

As described later, the first control means 111a and the second control means 111b are effective in the first driving region (AF possible region) of the focus lens 105, and the first control means 111a is ineffective in the second driving region (MF exclusive region) of the focus lens 105. When the second control is set by the setting means 111d, the third control means 111c performs control as follows. That is, when the focus lens is located in the first driving region and the second driving region changes so that the position of the focus lens is included in the second driving region when the subject distance is maintained, the third control means 111c drives the focus lens to maintain the subject distance. Also, when the focus lens is located in the second driving region and the second driving region changes so that the position of the focus lens is included in the first driving region when the subject distance is maintained, the third control means 111c drives the focus lens to maintain the subject distance. In each embodiment, the third control unit 111c drives the focus lens 105 based on the increase or decrease in the ratio of the second driving region to the entire driving region. The imaging optical system includes a field lens 101, a zoom lens 102 that performs magnification change, an aperture unit 103 that adjusts the amount of light, an image stabilization lens 104, and a focus lens 105 that performs focus adjustment. The zoom lens 102 can move in a direction along an optical axis OA indicated by a dashed line in the figure (optical axis direction), and is driven in the optical axis direction by a user operating a zoom operation unit connected to a zoom mechanism (not shown). As a result, the movement of the zoom lens 102 changes the magnification (zoom) of the imaging optical system, changing the focal length.

The zoom lens position detection unit 106 detects the zoom lens position using a position detection sensor such as a variable resistor, and outputs position data of the zoom lens 102 to the lens microcomputer 111. The position data output from the zoom lens position detection unit 106 is used by the lens microcomputer 111 for zoom tracking control, which will be described later.

The aperture unit 103 is configured with aperture blades and sensors such as Hall elements. The state of the aperture blades is detected by the aforementioned sensors and output to the lens microcomputer 111. The aperture control unit 107 outputs a drive signal according to commands from the lens microcomputer 111 to drive actuators such as a stepping motor and a voice coil motor. This allows the aperture unit 103 to adjust the amount of light.

The image stabilization lens 104 reduces image shake caused by camera shake and the like by moving in a direction perpendicular to the optical axis OA of the imaging optical system. The image stabilization lens control unit 108 outputs a drive signal to drive the anti-shake actuator according to a command from the lens microcomputer 111 in response to shake detected by a shake sensor (not shown) such as a vibration gyro. This allows anti-shake processing to be performed that controls the shift operation of the image stabilization lens 104.

The focus lens 105 is movable in the optical axis direction, and detects the position of the focus lens 105 using a position detection sensor such as a photointerrupter, and outputs the position data to the lens microcomputer 111. The focus lens control unit 109 outputs a drive signal according to a command from the lens microcomputer 111 to drive an actuator such as a stepping motor, and adjusts the focus by moving the focus lens 105.

The focus lens 105 also corrects image plane fluctuations that occur when the zoom lens 102 is used to change the magnification. In a rear-focus type variable magnification optical system, the image plane fluctuations that occur when the zoom lens 102 is moved to change the magnification are corrected by moving the focus lens 105, and zoom tracking control is performed to maintain the in-focus state.

Now, referring to FIG. 2, the zoom tracking control will be described. FIG. 2 is a diagram showing electronic cam data for each subject distance. In FIG. 2, the horizontal axis indicates the position of the zoom lens 102 (zoom lens position), and the vertical axis indicates the position of the focus lens 105 (focus lens position). To perform zoom tracking control, electronic cam data (tracking curve) information is stored in a memory (internal memory) (not shown) mounted on the lens microcomputer 111. As shown in FIG. 2, the electronic cam data is data indicating the relationship between the zoom lens position and the focus lens position set to maintain a focused state according to the subject distance. The lens microcomputer 111 outputs a control command to the focus lens control unit 109 based on the electronic cam data, and drives the focus lens 105 to perform tracking control.

In each embodiment, the electronic cam data is created based on the focus sensitivity, which is the amount of image plane movement per unit drive amount of the focus lens 105. However, as shown in FIG. 2, the electronic cam data actually stored in memory is data corresponding to a number of representative subject distances A to D, and is data indicating the focus lens position relative to a representative zoom lens position (representative point). The focus lens position can be calculated by calculating the ratio of the distance to a number of representative points close to the zoom lens position other than the representative point, and performing linear interpolation according to that ratio.

Next, the AF possible area and the MF dedicated area will be described with reference to FIG. 3. FIG. 3 is a diagram showing the AF possible area and the MF dedicated area. Here, the AF possible area is an area where focus adjustment is possible with both AF and MF, and the MF dedicated area is an area where focus adjustment is possible only with MF. In this embodiment, the AF possible area is the area between the AF/MF infinity end and the AF end, and the MF dedicated area is the area between the MF closest end and the AF closest end. Also, in this embodiment, the area combining the AF possible area and the MF dedicated area is the total driving area.

The imaging device 10 of each embodiment is capable of driving the focus lens 105 to perform focus adjustment in autofocus (AF) for automatic focus adjustment and manual focus (MF) for manual focus adjustment. The camera microcomputer 206 acquires the setting state of the focus mode selected by the user via the focus mode switch 112 via the camera communication unit, and determines whether the user has set the focus mode to AF mode or MF mode. When AF mode is selected, the camera microcomputer 206 transmits a control command related to focusing to the lens microcomputer 111. On the other hand, when MF mode is selected, the camera microcomputer 206 does not transmit a control command related to focusing, and prioritizes the operation of the operation ring 110.

In AF, the camera microcomputer 206 calculates the in-focus position of the focus lens 105 based on an AF evaluation value corresponding to the video signal generated by the image sensor 201, and transmits a control command related to focusing to the lens microcomputer 111 via the camera communication unit. In response to the control command transmitted from the camera microcomputer 206, the lens microcomputer 111 outputs a command to the focus lens control unit 109, and drives the focus lens 105 to control the focus adjustment operation. In MF, the lens microcomputer 111 outputs a command to the focus lens control unit 109 according to the amount of operation of the operation ring 110, and drives the focus lens 105 to control the focus adjustment operation.

The AF-enabled area shown in FIG. 3 is an area where focus adjustment is possible by both AF and MF. Therefore, subject B present in the AF-enabled area can be focused by both AF and MF. On the other hand, the MF-only area shown in FIG. 3 is an area where focus adjustment by AF is not possible and only focus adjustment by MF is possible because the AF evaluation value cannot be calculated accurately. Therefore, subject A present in the MF-only area can only be focused in MF. At this time, even if the user has selected AF mode with the focus mode switch 112, the area is one where focus adjustment by AF is not possible and MF mode is selected.

The control method for the imaging device 10 in each embodiment will be described in detail below.

First, a first embodiment of the present invention will be described. In this embodiment, the flow of focus lens control by zoom tracking processing will be described. FIG. 4 is a diagram showing the relationship between the zoom lens position and the minimum shooting distance. In FIG. 4, the vertical axis indicates the zoom lens position (position of the zoom lens 102), and the horizontal axis indicates the minimum shooting distance. As shown in FIG. 4, the minimum shooting distance changes depending on the position of the zoom lens 102, and a shooting distance position that is an AF possible area on the WIDE side becomes an MF-only area on the TELE side. In this way, in this embodiment, the AF possible area (AF/MF possible area) and the MF-only area switch depending on the zoom position.

Next, referring to FIG. 5, the flow of focus lens control (control method) when switching between the AF-enabled area (first driving area) and the MF-only area (second driving area) by the zoom tracking process in this embodiment will be described. FIG. 5 is a flowchart of the control method in this embodiment.

First, in step S500, the lens microcomputer 111 starts processing. Next, in step S501, the lens microcomputer 111 acquires position data (zoom lens position) of the zoom lens 102 using a signal detected by the position detection sensor of the zoom lens position detection unit 106. Next, in step S502, the lens microcomputer 111 compares the zoom lens position acquired previously with the zoom lens position detected in step S501, and determines whether or not a zoom operation has been performed. If a zoom operation has been performed in step S502, the process proceeds to step S503. On the other hand, if a zoom operation has not been performed, the process returns to step S501.

In step S503, the lens microcomputer 111 calculates a target focus lens position that maintains the subject distance at the current zoom lens position based on electronic cam data (tracking curve) that indicates the relationship between the zoom lens position and the focus lens position. The electronic cam data is stored, for example, in the memory of the lens microcomputer 111.

Now, referring to FIG. 6, we will explain the target focus lens position that maintains the subject distance. FIG. 6 is an explanatory diagram of the control method in this embodiment, and shows focus control that maintains the subject distance when the focus mode is MF mode during zoom tracking processing. In FIG. 6, the vertical axis indicates the focus lens position, and the horizontal axis indicates the zoom lens position. As shown in FIG. 6, it is assumed that the current focus lens position a1 is on the electronic cam at subject distance A. At this time, when a zoom operation is performed and the zoom lens position moves from focal length A to focal length B, the target focus lens position that maintains subject distance A becomes b1.

Next, in step S504 in FIG. 5, the lens microcomputer 111 determines whether or not AF mode has been selected by the focus mode switch 112. If MF mode has been selected in step S504, the process proceeds to step S507. In step S507, the lens microcomputer 111 outputs a control command to the focus lens control unit 109 to drive the focus lens 105 to the target focus position. As shown in FIG. 6, the lens microcomputer 111 drives the focus lens 105 so that the current focus lens position a1 moves to the target focus position b1, thereby maintaining the subject distance.

On the other hand, if AF mode is selected in step S504, the process proceeds to step S505. In step S505, the lens microcomputer 111 determines whether the target focus lens position calculated in step S503 is within the range of the MF-only area at the current zoom lens position. The memory of the lens microcomputer 111 stores the closest end data (AF closest end) of the AF-enabled area at each zoom lens position. Therefore, the lens microcomputer 111 can determine whether the target focus lens position is within the AF-enabled area or the MF-only area depending on whether the target focus lens position is closer to the AF closest end or on the infinity side.

Figure 7 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the AF possible area when the focus lens position before zoom tracking processing was in the AF possible area. In Figure 7, the vertical axis indicates the focus lens position, and the horizontal axis indicates the zoom lens position. As shown in Figure 7, the target focus lens position b2 is closer than the AF close end. Therefore, the target focus lens position b2 is determined to be in the MF-only area.

Next, in step S506, the lens microcomputer 111 determines whether the current focus lens position is within the AF possible area or the MF exclusive area depending on whether the current focus lens position is closer to the AF closest end or closer to infinity. If it is determined in step S506 that the current focus lens position is within the AF possible area, the process proceeds to step S508. In step S508, the lens microcomputer 111 (third control means 111c) outputs a control command to the focus lens control unit 109 to drive the focus lens 105 to the AF closest end. As shown in FIG. 7, the current focus lens position a2 is on the infinity side of the AF closest end. Therefore, the lens microcomputer 111 determines that the current focus lens position a2 is within the AF possible area, and drives the focus lens 105 to the AF closest end c2 to maintain the AF possible area. That is, when the focus lens is located in the AF-enabled area, if the MF-only area changes so that the position of the focus lens is included in the MF-only area when maintaining the subject distance, the third control means 111c drives the focus lens to be located in the AF-enabled area.

If it is determined in step S505 that the target focus lens position is within the AF possible area, the process proceeds to step S507. In step S507, the lens microcomputer 111 (third control means 111c) outputs a control command to the focus lens control unit 109 to drive the focus lens 105 to the target focus position. That is, when the focus lens is located in the AF possible area, if the MF dedicated area changes so that the position of the focus lens is included in the AF possible area when maintaining the subject distance, the third control means 111c drives the focus lens to maintain the subject distance. Also, when the focus lens is located in the MF dedicated area, if the MF dedicated area changes so that the position of the focus lens is included in the AF possible area when maintaining the subject distance, the third control means 111c drives the focus lens to maintain the subject distance.

Figure 8 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the subject distance when the focus lens position before zoom tracking processing was in the AF possible range. In Figure 8, the vertical axis indicates the focus lens position, and the horizontal axis indicates the zoom lens position. As shown in Figure 8, the target focus lens position b3 is on the infinity side of the AF close end. Therefore, the lens microcomputer 111 determines that the target focus lens position b3 is in the AF possible range, and drives the focus lens 105 to the target focus position b3 to maintain the subject distance.

If it is determined in step S506 that the current focus lens position is in the MF-only region, the process proceeds to step S507. In step S507, the lens microcomputer 111 outputs a control command to the focus lens control unit 109 to drive the focus lens 105 to the target focus lens position.

Figure 9 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the subject distance when the focus lens position before zoom tracking processing is in the MF-only region. In Figure 9, the vertical axis indicates the focus lens position, and the horizontal axis indicates the zoom lens position. As shown in Figure 9, the current focus lens position a4 is closer than the AF close end. Therefore, the lens microcomputer 111 determines that the current focus lens position a4 is within the MF-only region, and drives the focus lens 105 to the target focus position b4 to maintain the subject distance.

In this embodiment, the MF dedicated area changes depending on the position of the zoom lens. Also, in this embodiment, when the zoom lens is at the wide-angle end (WIDE), the MF dedicated area has a first width, and when the zoom lens is at the telephoto end (TELE), the MF dedicated area has a second width that is narrower than the first width. However, this embodiment is not limited to this, and the relationship between the zoom lens position (wide-angle end, telephoto end) and the width of the MF dedicated area (first width, second width) may be reversed.

As described above, in this embodiment, when MF mode is selected by the user, the focus lens 105 is driven to a target focus lens position that maintains the subject distance, regardless of the area of the focus lens position before and after the zoom tracking process is performed. This makes it possible to maintain the focus state (in-focus state) of the subject.

On the other hand, when the AF mode is selected by the user, the control of the focus lens 105 is switched depending on the area of the focus lens position before and after the zoom tracking process is performed. When the focus lens position before the zoom tracking process is an AF possible area and the target focus lens position where the subject distance is maintained by the zoom tracking process is an MF-only area, the control is performed as follows. That is, the focus lens 105 is prohibited from moving from the AF possible area to the MF-only area by an operation other than the MF operation by the user. This makes it possible to prevent the focus lens 105 from moving from the AF possible area to the MF-only area unintentionally by the user. In addition, when the focus lens position before the zoom tracking process is an MF-only area, the focus state of the subject can be maintained by driving the focus lens 105 to a target focus lens position where the subject distance is maintained. In this way, by switching the control of the focus lens 105 depending on the user's focus mode setting and the area of the focus lens position before and after the zoom tracking process is performed, the operability for the user can be improved.

Next, a second embodiment of the present invention will be described. In the interchangeable lens 100 of this embodiment, when the light flux reaching the phase difference AF sensor of the image sensor 201 becomes smaller due to the aperture unit 103 that limits the amount of light in the subject image, the accuracy of the AF evaluation value decreases, and there is an area where high-precision AF cannot be achieved (AF impossible area). In this embodiment, the area where high-precision AF cannot be achieved due to the influence of the aperture unit 103 is designated as an MF-only area.

Figure 10 is a diagram showing the relationship between aperture value (F-number) and minimum shooting distance. In Figure 10, the vertical axis indicates aperture value, and the horizontal axis indicates minimum shooting distance. As shown in Figure 10, the minimum shooting distance changes depending on the aperture value, and a shooting distance position that is in the AF possible area at the widest aperture becomes an MF-only area at the smallest aperture. In this way, in this embodiment, the AF possible area (AF/MF possible area) and the MF-only area switch depending on the aperture value.

Next, referring to FIG. 11, the flow of focus lens control (control method) when switching between the AF-enabled area and the MF-only area due to a change in aperture value in this embodiment will be described. FIG. 11 is a flowchart of the control method in this embodiment.

First, in step S1100, the lens microcomputer 111 starts processing. Next, in step S1101, the lens microcomputer 111 acquires the aperture value that was set in response to the control command sent from the camera body 200. Next, in step S1102, the lens microcomputer 111 compares the aperture value acquired in step S1101 with the aperture value acquired previously, and determines whether the aperture value has changed. If it is determined in step S1102 that the aperture value has changed, the process proceeds to step S1103. On the other hand, if it is determined that the aperture value has not changed, the process returns to step S1101, and the lens microcomputer 111 acquires the aperture value.

If it is determined in step S1102 that the aperture value has changed, in step S1103, the lens microcomputer 111 determines whether or not the AF mode has been selected by the focus mode switch 112. If the MF mode has been selected in step S1103, the lens microcomputer 111 does not drive the focus lens 105.

Figure 12 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the subject distance when the focus mode is MF mode when the aperture value is changed. In Figure 12, the vertical axis indicates the focus lens position, and the horizontal axis indicates the aperture value. As shown in Figure 12, the subject distance is maintained without driving the focus lens 105 before the aperture value is changed (aperture value A) and after the aperture value is changed (aperture value B).

In step S1104, the lens microcomputer 111 determines whether the focus lens position before the change in aperture value is within the AF possible area. The lens microcomputer 111 stores in memory the closest end data (AF closest end) of the AF possible area for each aperture value. The lens microcomputer 111 then determines whether the focus lens position before the change in aperture value is in the AF possible area or the MF-only area, depending on whether the focus lens position before the change in aperture value is closer to the AF closest end or on the infinity side.

Figure 13 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the subject distance when the focus lens position before the aperture value is changed is in the AF possible area. In Figure 13, the vertical axis indicates the focus lens position, and the horizontal axis indicates the aperture value. As shown in Figure 13, when the aperture value is changed from aperture value A to aperture value B, the focus lens position a6 before the aperture value change (aperture value A) is on the infinity side of the AF closest end. For this reason, the lens microcomputer 111 determines that the focus lens position a6 before the aperture value change is in the AF possible area.

If it is determined in step S1104 that the focus lens position before the aperture value change is in the AF possible range, the process proceeds to step S1105. In step S1105, the lens microcomputer 111 determines whether the focus lens position after the aperture value change is within the AF possible range. The lens microcomputer 111 determines whether the focus lens position after the aperture value change is in the AF possible range or the MF-only range, depending on whether the focus lens position after the aperture value change is closer or closer to the infinity side than the AF close end. As shown in FIG. 13, the focus lens position b6 after the aperture value change (aperture value B) is closer to the infinity side than the AF close end. Therefore, the lens microcomputer 111 determines that the focus lens position b6 after the aperture value change is in the AF possible range, and maintains the subject distance without driving the focus lens 105.

If it is determined in step S1104 that the focus lens position before the change in aperture value is in the MF-only area, the lens microcomputer 111 does not drive the focus lens 105.

Figure 14 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the subject distance when the focus lens position before the aperture value is changed is in the MF-only region. In Figure 14, the vertical axis indicates the focus lens position, and the horizontal axis indicates the aperture value. As shown in Figure 14, the focus lens position a7 before the aperture value is changed is closer than the AF close end. Therefore, the lens microcomputer 111 determines that the focus lens position a7 before the aperture value is changed is in the MF-only region, and maintains the subject distance without driving the focus lens 105.

If it is determined in step S1105 that the focus lens position after the aperture value change is in the MF-only region, the process proceeds to step S1106. In step S1106, the lens microcomputer 111 outputs a control command to the focus lens control unit 109 to drive the focus lens 105 to the AF closest end.

Figure 15 is an explanatory diagram of the control method in this embodiment, showing focus control that maintains the AF possible area when the focus lens position before the aperture value is changed becomes the AF possible area. In Figure 15, the vertical axis indicates the focus lens position, and the horizontal axis indicates the aperture value. As shown in Figure 15, the focus lens position b8 after the aperture value is changed is closer than the AF close end. Therefore, the lens microcomputer 111 determines that the focus lens position b8 after the aperture value is changed is in the MF-only area, and drives the focus lens 105 to the AF close end c8 to maintain the AF possible area.

As described above, in this embodiment, when the MF mode is selected by the user, the position of the focus lens 105 is maintained and the focus state of the subject is maintained regardless of the area of the focus lens position before and after the change in the aperture value. On the other hand, when the AF mode is selected by the user, the control of the focus lens 105 is switched depending on the area of the focus lens position before and after the change in the aperture value. When the focus lens position before the change in the aperture value is an AF possible area and is switched to an MF-only area by changing the aperture value, the focus lens 105 is driven to the range of the AF possible area so that the AF possible area is not switched to the MF-only area by anything other than the MF operation by the user. This makes it possible to prevent the user from unintentionally changing from the AF possible area to the MF-only area. On the other hand, when the focus lens position before the change in the aperture value is an MF-only area, the position of the focus lens 105 is maintained to maintain the focus state of the subject. In this way, by switching the control of the focus lens 105 depending on the user's focus mode setting and the area of the focus lens position before and after the change in the aperture value, the operability for the user can be improved.

Other Examples
The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

According to each embodiment, it is possible to provide a control device, lens device, imaging device, control method, and program that can reflect the user's intentions, prevent switching from an AF-enabled area to an MF-only area due to reasons other than MF operation, and improve user operability.

The above describes preferred embodiments of the present invention, but the present invention is not limited to these embodiments, and various modifications and variations are possible within the scope of the gist of the invention.

In each embodiment, the lens microcomputer 111 executes the functions of the first control means 111a, the second control means 111b, the third control means 111c, and the setting means 111d, but is not limited to this. For example, the camera microcomputer 206 as a control device may be configured to execute at least one function of the first control means, the second control means, the third control means, or the setting means.

111 Lens microcomputer (control device)
111a: first control means 111b: second control means 111c: third control means 111d: setting means

Claims (11)

a first control means for automatically adjusting the focus lens to a focus position;
A second control means for adjusting the focus lens based on an amount of operation by a user;
a third control means for driving the focus lens;
a setting means for setting a first control by the first control means and a second control by the second control means to be switchable;
the first control means and the second control means are effective in a first driving range of the focus lens,
the first control means is ineffective in a second driving region of the focus lens,
the second control means is effective in the second driving region,
When the second control is set by the setting means, the third control means
a control device that drives the focus lens to maintain the subject distance before and after the change in the second driving region when the focus lens is located in the first driving region and the second driving region changes so that the position of the focus lens is included in the second driving region when maintaining the subject distance, or when the focus lens is located in the second driving region and the second driving region changes so that the position of the focus lens is included in the first driving region when maintaining the subject distance. When the first control is set by the setting means, the third control means
The control device according to claim 1, characterized in that when the focus lens is located in the first driving region and the second driving region changes so that the position of the focus lens is included in the second driving region when maintaining a subject distance, the control device drives the focus lens so that the focus lens is located in the first driving region. The control device according to claim 1 or 2, characterized in that the third control means drives the focus lens to maintain the subject distance when the focus lens is located in the first driving region and the second driving region changes so that the position of the focus lens is included in the first driving region when maintaining the subject distance. When the first control is set by the setting means, the third control means
A control device as described in any one of claims 1 to 3, characterized in that when the focus lens is located in the second driving region and the second driving region changes so that the position of the focus lens is included in the first driving region when maintaining the subject distance, the control device drives the focus lens to maintain the subject distance. The control device according to any one of claims 1 to 4, characterized in that the second driving region changes depending on the position of the zoom lens. When the zoom lens is at a wide-angle end, the second driving region has a first width;
6. The control device according to claim 5, wherein when the zoom lens is at a telephoto end position, the second driving region has a second size narrower than the first size. The control device according to any one of claims 1 to 6, characterized in that the second driving region changes according to the aperture value. When the aperture value is a first aperture value, the second driving region has a third size;
8. The control device according to claim 7, wherein when the aperture value is a second aperture value smaller than the first aperture value, the second driving region has a fourth size smaller than the third size. The control device according to any one of claims 1 to 8, characterized in that the third control means drives the focus lens based on an increase or decrease in the ratio of the second driving region to the entire driving region. A focus lens;
A lens device comprising: a control device according to claim 1 . An imaging element;
An imaging device comprising: the control device according to claim 1 .