Accessory and control method thereof

Abstract

To effectively use limited power in an accessory.SOLUTION: The accessory 100 is used together with the image pickup apparatus 200. The accessory includes a first driving unit 110 configured to drive the first movable member 104, a second driving unit 112 configured to drive the second movable member 105, and a control unit 114 configured to control electric power for driving the first and second driving units. When the posture of the accessory is changed from the first posture to the second posture, the electric power used for driving one of the first and second driving means is increased, and the electric power used for driving the other is decreased. An upper limit value of power usable for driving the first and second driving means is changed according to the detected attitude.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to accessories such as lens devices used with imaging devices. [Background technology]

[0002] In lens devices, movable members such as the aperture, vibration-proof lens, focus lens, and zoom lens are driven electrically, and these movable members are often driven simultaneously. Lens devices receive power from the imaging device to which they are attached to drive these movable members, but there are limits to the amount of power that can be used.

[0003] Patent Document 1 discloses a lens device that drives a lens in a power-saving mode when the lens device is in a horizontal position and requires less drive power for a lens that can move in the optical axis direction, and drives the lens in a normal mode when the lens device is in a vertical position and requires more drive power.Patent Document 2 discloses an imaging device that, when the total amount of power that can be supplied to a plurality of drive units decreases, reduces the total amount of power while maintaining the ratio of the amount of power supplied to each of the plurality of drive units. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-189506 [Patent Document 2] Patent No. 6746014 Summary of the Invention [Problem to be solved by the invention]

[0005] In a lens apparatus in which a plurality of movable members are often driven simultaneously as described above, it is required to use the limited power effectively. [Means for solving the problem]

[0006] One aspect of the present invention is an accessory for use with an imaging device. The accessory has a first drive means for driving a first movable member, a second drive means for driving a second movable member, and a control means for controlling the power for driving the first and second drive means. When the accessory's attitude changes from the first attitude to the second attitude, the power used to drive one of the first and second drive means increases and the power used to drive the other decreases. The control means changes the upper limit of the power available for driving the first and second drive means in accordance with the detected attitude.

[0007] Another aspect of the present invention provides a control method applied to an accessory used with an imaging device. The accessory has a first drive means for driving a first movable member and a second drive means for driving a second movable member. The control method includes the steps of: acquiring the detected attitude of the accessory when a change in attitude of the accessory from the first attitude to a second attitude causes an increase in power used to drive one of the first and second drive means and a decrease in power used to drive the other of the first and second drive means; and changing an upper limit of power available for driving the first and second drive means in accordance with the attitude. [Effects of the Invention]

[0008] According to the present invention, an accessory that can make effective use of limited power can be provided. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing the configuration of an imaging system according to an embodiment. [Figure 2] 3A and 3B are diagrams showing the posture of the imaging system according to the embodiment. [Figure 3] FIG. 10 is a diagram showing a conventional power upper limit value. [Figure 4] FIG. 10 is a diagram showing upper power limits as a comparative example. [Figure 5] FIG. 10 is a diagram showing (another) upper power limit values ​​in the embodiment. [Figure 6] FIG. 10 is a diagram showing distribution of surplus power in an embodiment. [Figure 7] 10 is a flowchart showing a power upper limit setting process in the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] 1 shows the configuration of an imaging system having an interchangeable lens (lens device) 100 as an accessory of the embodiment, and a camera body 200 as an imaging device to which the interchangeable lens 100 is detachably attached. Attached to the interchangeable lens 100 is an adapter 300 as an accessory that performs zooming by rotating a zoom operation ring (not shown) provided on the interchangeable lens 100 from outside the interchangeable lens 100.

[0012] The interchangeable lens 100 has an imaging optical system that includes, in order from the subject side (the left side of the figure), a fixed front lens 101, a variable magnification lens 102, an aperture 103, an anti-vibration lens 104, and a focus lens 105. Each lens is made up of one or more lens elements.

[0013] The variable magnification lens 102 performs zooming by moving to the telephoto side and the wide-angle side in the optical axis direction (first direction), which is the direction along the optical axis OA. In this embodiment, the variable magnification lens 102 moves in the optical axis direction when the zoom operation ring is rotated by the user or when the zoom operation ring is rotated by the adapter 300.

[0014] The aperture 103 adjusts the amount of light by changing the aperture diameter using an aperture actuator 108 configured by a stepping motor, a DC motor, etc. An aperture drive circuit 109 supplies a drive voltage and a drive current to the aperture actuator 108.

[0015] The vibration-proof lens (first movable member) 104 is moved in a direction perpendicular to the optical axis direction (second direction) by an vibration-proof actuator (first driving means) 110 formed by a voice coil motor (VCM), thereby reducing (correcting) image blur caused by camera shake such as hand shake. An vibration-proof driving circuit 111 supplies a driving voltage and a driving current to the vibration-proof actuator 110. The VCM as the vibration-proof actuator 110 is formed by a driving coil and a magnet (not shown), and when a current flows through the driving coil in the magnetic field of the magnet, the vibration-proof lens 104 is shifted in a plane perpendicular to the optical axis direction or rotated about a point on the optical axis OA.

[0016] Focus lens (second movable member) 105 is driven in the optical axis direction by a focus actuator (second driving means) 112 configured with a VCM to perform focus adjustment (focusing). A focus driving circuit 113 supplies a driving voltage and a driving current to focus actuator 112. The VCM as focus actuator 112 is configured with a driving coil and a magnet (not shown), and drives focus lens 105 toward the infinity side and the close-up side in the optical axis direction by passing a current through the driving coil in the magnetic field of the magnet. Note that focus actuator 112 may also be configured with a stepping motor or a vibration motor.

[0017] The vibration reduction drive circuit 111 and the focus drive circuit 113 use the PWM method to drive the vibration reduction actuator 110 and the focus actuator 112. A lens CPU 114 serving as a control means transmits control signals to notify (instruct) the vibration reduction drive circuit 111 and the focus drive circuit 113 of the PWM duty ratio, and each drive circuit drives each actuator at the PWM duty ratio according to the received control signal.

[0018] The attitude detection section (attitude detection means) 123 includes an acceleration sensor, detects the attitude of the imaging system 10, and outputs a signal indicating the attitude to the lens CPU 114.

[0019] The interchangeable lens 100 is provided with electrical contacts 116a, 116b, and 116c, which are electrically connected to electrical contacts 209a, 209b, and 209c provided on the camera body 200, respectively. This enables communication of various types of information between the interchangeable lens 100 (lens CPU 114) and the camera CPU 206 provided in the camera body 200. This embodiment shows a case where the lens CPU 114 and the camera CPU 206 perform three-wire serial communication with the camera CPU 206 as the clock master. However, other communication methods may also be used.

[0020] When the adapter 300 is attached to the interchangeable lens 100, electrical contacts 118a, 118b, and 118c provided on the interchangeable lens 100 are electrically connected to electrical contacts 303a, 303b, and 303c provided on the adapter 300, respectively. This enables communication of various types of information between the lens CPU 114 and the adapter CPU 301 provided in the adapter 300. In this embodiment, the lens CPU 114 and the adapter CPU 301 perform three-wire serial communication with the lens CPU 114 as the clock master. However, other communication methods may also be used.

[0021] The interchangeable lens 100 holds, as its unique information, identification information, optical information (focal length, aperture value, focus sensitivity, focus correction amount, etc.), and characteristic information (maximum communication speed, maximum F-number, whether zoom is possible, whether autofocus is possible, power mode, etc.). The interchangeable lens 100 transmits this information to the camera body 200. Furthermore, when an adapter 300 is attached to the interchangeable lens 100, characteristic information of the adapter 300 (zoom drive speed, maximum communication speed, etc.) is transmitted to the camera body 200 via the interchangeable lens 100. Furthermore, the interchangeable lens 100 receives identification information, power consumption information, etc. from the attached adapter 300.

[0022] Power contacts 117a, 117b, 117c, and 117d provided on the interchangeable lens 100 are electrically connected to power contacts 210a, 210b, 210c, and 210d provided on the camera body 200, respectively. This allows power to be supplied to the interchangeable lens 100 from the camera body 200. Note that power may also be supplied to the interchangeable lens 100 from an external power source other than the camera body 200. Furthermore, power contacts 119a, 119b, 119c, and 119d provided on the interchangeable lens 100 are electrically connected to power contacts 304a, 304b, 304c, and 304d provided on the adapter 300, respectively. This allows power to be supplied to the adapter 300 from the interchangeable lens 100. In other words, power is supplied from the camera body 200 to the adapter 300 via the interchangeable lens 100.

[0023] Power contacts 117a, 210a, 119a, and 304a are system power terminals for supplying power to various sensors (not shown), the lens CPU 114, the adapter CPU 301, and the adapter operation unit 309. Power contacts 117b, 210b, 119b, and 304b are ground terminals for the system power terminals. Power contacts 117c, 210c, 119c, and 304c are power power terminals for supplying power to each drive circuit, and power contacts 117d, 210d, 119d, and 304d are ground terminals for the power power terminals. The camera body 200 is equipped with a secondary battery 208 such as a lithium-ion battery, and power converted to a predetermined voltage by a camera power supply circuit 207 such as a DC-DC converter is supplied from the secondary battery 208 to the interchangeable lens 100 and the adapter 300.

[0024] The lens power supply circuit 115 provided in the interchangeable lens 100 is a power conversion circuit such as a DC-DC converter, which converts the power supplied from the camera body 200 into power of a voltage suitable for the various sensors and drive circuits and distributes it to them. The adapter power supply circuit 302 provided in the adapter 300 is a power conversion circuit such as a DC-DC converter, which converts the power supplied from the camera body 200 via the power contacts of the interchangeable lens 100 into power of a voltage suitable for the various sensors and drive circuits and distributes it to them.

[0025] When the adapter 300 is attached to the interchangeable lens 100 while the interchangeable lens 100 is attached to the camera body 200, the lens CPU 114 controls the ON / OFF of the system power supply control switch 120 and the power power supply control switch 121 inside the interchangeable lens 100. This allows power to be supplied to the adapter 300 at the appropriate timing. At the same time, the adapter CPU 301 in the adapter 300 controls the ON / OFF of the power power supply control switch 305. This allows power to be supplied to the drive circuit 310 and zoom actuator 311 at the appropriate timing.

[0026] The camera body 200 has an image sensor 201 as a photoelectric conversion element such as a CMOS sensor. The image sensor 201 photoelectrically converts an optical image (subject image) formed on its imaging surface by an imaging optical system. The electric charges accumulated in the image sensor 201 by photoelectric conversion are output as an image signal (analog signal) at a predetermined timing, and the image signal is input to a video signal processing circuit 202.

[0027] The video signal processing circuit 202 converts the analog image signal from the image sensor 201 into a digital image signal and performs various signal processing such as amplification and gamma correction on the digital image signal to generate a video signal. The video signal is output to a camera CPU 206, a display unit 205 formed of a liquid crystal panel or the like, and a storage unit 204 formed of an optical disk, semiconductor memory or the like.

[0028] The video signal processing circuit 202 has an AF signal processing circuit 203. The AF signal processing circuit 203 extracts high-frequency components and luminance components obtained by a group of pixels in an AF area, which is a focus detection area, from the image signal (or video signal) output from the image sensor 201 to generate a focus evaluation signal. The focus evaluation signal indicates the contrast state of the video signal, that is, the sharpness, and changes as the focus lens 105 moves. The position of the focus lens 105 at which the value of the focus evaluation signal, that is, the focus evaluation value, reaches its maximum (peak) is the in-focus position.

[0029] The camera CPU 206 has a power information processing unit 213. Based on the power consumption information received from the lens CPU 114, the power information processing unit 213 performs efficient power management by changing the settings of the power supply to the interchangeable lens 100 and the adapter 300, the resolution and frame rate at which images can be captured, and the like.

[0030] The lens CPU 114 has a power upper limit setting unit 122. The power upper limit setting unit 122 determines the amount of power supply to the adapter 300 based on the power consumption information received from the adapter CPU 301, and determines the power upper limit value for the interchangeable lens 100 when the adapter 300 is connected according to the amount of power supply.

[0031] The upper power limits in this embodiment include the upper limit of power that can be used to drive the anti-vibration actuator 110, the upper limit of power that can be used to drive the focus actuator 112, and the sum of these. In the following description, the power that is actually used to drive the anti-vibration actuator 110 is referred to as the actual power use of the anti-vibration actuator 110, and the power that is actually used to drive the focus actuator 112 is referred to as the actual power use of the focus actuator 112. Note that the driving of the anti-vibration actuator 110 here also includes the operations of the lens CPU 114 and anti-vibration drive circuit 111 that control the driving of the anti-vibration actuator 110. Similarly, the driving of the focus actuator 112 includes the operations of the lens CPU 114 and focus drive circuit 113 that control the driving of the focus actuator 112.

[0032] The power upper limit value set by the power upper limit setting unit 122 is transmitted from the lens CPU 114 to the camera CPU 206. Even when the adapter 300 is not connected to the interchangeable lens 100, the lens CPU 114 transmits the power upper limit value of the interchangeable lens 100 to the camera body 200.

[0033] The adapter CPU 301 has a power consumption information communication unit 312 and a power supply determination unit 313. The power supply determination unit 313 determines whether an external power supply for the adapter is connected to a power connector (not shown) and whether power is being supplied. By supplying power directly from the external power supply for the adapter, there is no upper limit on the power supply, so that even if the required power changes due to changes in posture or temperature, there is no impact on operation. In other words, the power consumption information communication unit 312 determines whether power supplied from the camera body 200 via the interchangeable lens 100 is necessary, and based on this determination result, the power consumption information communication unit 312 transmits information about the power consumption of the adapter 300 to the lens CPU 114. The temperature sensor (temperature detection means) 314 notifies the adapter CPU 301 of the detected temperature. The adapter CPU 301 notifies the lens CPU 114 of the detected temperature.

[0034] An adapter operation unit 309 provided in the adapter 300 detects zoom operations by the user. The adapter CPU 301 outputs a control signal to a drive circuit 310 in response to the detected zoom operation, and the drive circuit 310 drives a zoom actuator 311 in response to the control signal. The zoom actuator 311 rotates a zoom operation ring of the interchangeable lens 100 via a gear train (not shown). This realizes power zooming of the interchangeable lens 100.

[0035] In this embodiment, the PWM duty ratio for driving the anti-vibration actuator 110 and the focus actuator 112 is changed according to the attitude of the interchangeable lens 100 (image capture system 10) detected by the attitude detection unit 123. Here, the value to be added to the PWM duty ratio according to the attitude is taken as a retention addition amount, with a large value of this retention addition amount being "1" and a small value being "0".

[0036] 2(a) to 2(c) show the attitude of the imaging system 10. When the attitude of the imaging system 10 is the horizontal attitude shown in Fig. 2(a), it is necessary to hold the vibration-proof lens 104 in a neutral position on the optical axis OA against gravity. At this time, in order to prevent the vibration-proof lens 104 from moving downward due to its own weight, the holding addition amount for the vibration-proof actuator 110 is set to "1".

[0037] 2(b) from the horizontal attitude, the holding addition amount for the anti-vibration actuator 110 is made smaller than in the horizontal attitude in order to prevent downward movement due to a portion of the weight of the anti-vibration lens 104. Then, when the imaging system 10 is in the vertical attitude (upward or downward attitude) as shown in FIG. 2(c), it is no longer necessary to prevent downward movement due to the weight of the anti-vibration lens 104, so the weight holding addition amount for the anti-vibration actuator 110 is set to "0".

[0038] On the other hand, when the orientation of the imaging system 10 is the horizontal orientation shown in FIG. 2A, there is no need to prevent downward movement of the focus lens 105 due to its own weight, so the holding addition amount for the focus actuator 112 is set to "0." When the imaging system 10 changes from the horizontal orientation to the diagonally upward orientation shown in FIG. 2B, the holding addition amount for the focus actuator 112 is increased compared to the horizontal orientation in order to prevent downward movement due to a portion of the weight. Then, when the imaging system 10 changes to the vertical orientation shown in FIG. 2C, the holding addition amount for the focus actuator 112 is set to "1" in order to prevent downward movement of the focus lens 105 due to its own weight.

[0039] By controlling the retained addition amount in this way, in response to a change in attitude from a horizontal attitude (first attitude) to a vertical attitude (second attitude), the actual power consumption (power consumption) of the anti-vibration actuator 110 decreases and the actual power consumption of the focus actuator 112 increases. Furthermore, in response to the change in attitude, the total value of the actual power consumption of the anti-vibration actuator 110 and the focus actuator 112 changes.

[0040] Next, the upper power limits of the conventional anti-vibration (IS) actuator 110 and focus actuator 112 will be explained using Figures 3(a) and (b). Figures 3(a) and (b) respectively show examples of the upper power limits and total values ​​of the anti-vibration actuator 110 and focus actuator 112 in the horizontal and vertical orientations. Figures 3(a) and (b) also show examples of the actual power usage of the anti-vibration actuator 110 and focus actuator 112 and their total value.

[0041] As described above, the actual power consumption of the anti-vibration actuator 110 and the focus actuator 112 changes depending on the attitude of the imaging system 10. Meanwhile, the amount of power that can be supplied from the camera body 200 to the interchangeable lens 100 and the adapter 300 is predetermined and limited. For this reason, the power upper limit setting unit 122 sets a power upper limit value for the power distributed to the multiple actuators in the interchangeable lens 100 and the adapter 300.

[0042] One method for distributing power so as not to exceed the upper power limit is to set the PWM duty ratio notified from the lens CPU 114 to each drive circuit at a predetermined value or less. When the PWM duty ratio is limited, the effective voltage when the actuator is driven decreases, thereby limiting power consumption. When changes in the orientation of the imaging system 10 are taken into consideration, the actual power consumption of the anti-vibration actuator 110 is at its maximum when the system is in the horizontal orientation shown in FIG. 3(a), and the actual power consumption of the focus actuator 112 is at its maximum when the system is in the vertical orientation (facing up) shown in FIG. 3(b).

[0043] Generally, a method is used in which a power upper limit is set for each actuator according to the maximum value of the actual power used, and the power supplied to multiple actuators is allocated accordingly. This method keeps the power upper limit constant without changing it depending on the position. For example, assume that the power that can be supplied from the camera body 200 to the interchangeable lens 100 is set to 1.5 W. If the power used by actuators other than the anti-vibration actuator 110 and focus actuator 112, the lens CPU 114, each drive circuit, etc. is not taken into consideration, the power upper limit for the anti-vibration actuator 110 is set to 0.5 W, and the power upper limit for the focus actuator 112 is set to 1 W.

[0044] For example, in the horizontal position, the actual power usage for such a power upper limit is 0.3 W for the anti-vibration actuator 110 and 0.1 W for the focus actuator 112, for a total of 0.4 W. The total of 0.4 W is 1.1 W lower than 1.5 W. In the vertical position, the anti-vibration actuator 110 is 0.1 W and the focus actuator 112 is 0.8 W, for a total of 0.9 W. Although the total of 0.9 W is higher than in the horizontal position, it is 0.6 W lower than the 1.5 W power supplied from the camera body 200.

[0045] However, the fixed upper power limit of 1.5 W set for the anti-vibration actuator 110 and the focus actuator 112 is the same as the 1.5 W of power supplied from the camera body 200. For this reason, even though the actual power usage has a margin above the upper power limit as described above, it is not possible to ensure surplus power that can be supplied to other components within the interchangeable lens 100 (and other operating means that operate these: actuators and circuits) or the adapter 300.

[0046] In this embodiment, focusing on the fact that the actual power usage of the anti-vibration actuator 110 and the focus actuator 112 changes depending on the attitude, the upper power limit is changed based on the actual power usage that changes depending on the attitude. Furthermore, surplus power, which is the difference between the power supplied from the camera body 200 to the interchangeable lens 100 and the sum of the upper power limits of the anti-vibration actuator 110 and the focus actuator 112, is distributed to other operating parts within the interchangeable lens 100 and the adapter 300. This allows for efficient use of power in the interchangeable lens 100 and the adapter 300 without increasing the amount of power supplied from the camera body 200 to the interchangeable lens 100. Specifically, when the output torque required of the actuators increases at low temperatures or when the required power increases to improve the actuator performance (for example, speed), the surplus power is allocated to these.

[0047] 4(a) and 4(b) show, as comparative examples, examples of setting the total upper power limit values ​​of the anti-vibration actuator 110 and the focus actuator 112 in the horizontal and vertical positions, respectively. The lower parts of FIGS. 4(a) and 4(b) show examples of the upper power limit values ​​and their total value for the anti-vibration actuator 110 and the focus actuator 112 in the horizontal and vertical positions shown in FIGS. 3(a) and 3(b). Furthermore, FIGS. 4(a) and 4(b) also show examples of the actual power usage of the anti-vibration actuator 110 and the focus actuator 112 and their total value, as in FIGS. 3(a) and 3(b). Here, too, the power supplied from the camera body 200 is set to 1.5 W.

[0048] In this embodiment, the total of the power upper limits in the horizontal and vertical positions is set to 1.0 W based on the total value of 0.9 W in the vertical position, where the total value of the actual power used by the anti-vibration actuator 110 and the focus actuator 112 is higher than in the horizontal position. In this case, in the horizontal position, for example, the power upper limit of the anti-vibration actuator 110 may be set to 0.5 W, and the power upper limit of the focus actuator 112 may be set to 0.5 W. On the other hand, in the vertical position, for example, the power upper limit of the anti-vibration actuator 110 may be set to 0.2 W, and the power upper limit of the focus actuator 112 may be set to 0.8 W.

[0049] By setting the power upper limit in this way, a surplus power of 0.5 W is ensured in both the horizontal and vertical positions, which is the difference between the 1.5 W of power supplied from camera body 200 and the 1.0 W total power upper limit. However, in the horizontal position, the total actual power usage is set to 0.4 W, but the 0.6 W difference is set large, meaning that only 0.5 W can be effectively used. In other words, although there is still a margin of 0.6 W, only 0.5 W can be ensured as surplus power. 5(a) and 5(b) show (another) setting examples of the total upper power limit values ​​for the anti-vibration actuator 110 and the focus actuator 112 in the horizontal and vertical positions in this embodiment, respectively. The lower parts of FIGS. 5(a) and 5(b) show examples of the upper power limit values ​​and their total value for the anti-vibration actuator 110 and the focus actuator 112 in the horizontal and vertical positions shown in FIGS. 3(a) and 3(b). Furthermore, FIGS. 5(a) and 5(b) also show examples of the actual power usage and their total value for the anti-vibration actuator 110 and the focus actuator 112, as in FIGS. 3(a) and 3(b). Here again, the power supplied from the camera body 200 is set to 1.5 W.

[0050] In the horizontal position shown in Figure 5(a), the total upper power limit is set to 0.5 W based on a total of 0.4 W of actual power consumption by the anti-vibration actuator 110 and the focus actuator 112. In the vertical position shown in Figure 5(b), the total upper power limit is set to 1.0 W based on a total of 0.9 W of actual power consumption by the anti-vibration actuator 110 and the focus actuator 112. In this case, in the horizontal position, for example, the upper power limit for the anti-vibration actuator 110 may be set to 0.3 W and the upper power limit for the focus actuator 112 may be set to 0.2 W. In the vertical position, for example, the upper power limit for the anti-vibration actuator 110 may be set to 0.2 W and the upper power limit for the focus actuator 112 may be set to 0.8 W.

[0051] By setting the upper power limit value in this way, in the horizontal position, a surplus power of 1.0 W is ensured, which is the difference between the 1.5 W power supply from camera body 200 and the 0.5 W total upper power limit value. In addition, in the vertical position, a surplus power of 0.5 W is ensured, which is the difference between the 1.5 W power supply from camera body 200 and the 1.0 W total upper power limit value. In other words, more efficient power distribution is possible compared to the upper power limit value settings shown in Figures 4(a) and 4(b).

[0052] Fig. 6(a) shows an example of the power upper limit values ​​and actual power usage of the vibration damping, focus and zoom actuators 110, 112, 311 when the surplus power secured by the power upper limit value setting of Fig. 4(b) or Fig. 5(b) in the vertical position is allocated to driving the zoom actuator 311 of the adapter 300. Fig. 6(b) shows an example of the power upper limit values ​​and actual power usage of the vibration damping, focus and zoom actuators 110, 112, 311 when the power upper limit value setting shown in Fig. 3(b) is performed. Here, the power supplied from the camera body 200 is set to 2.5 W.

[0053] In the vertical position (upward position), the zoom lens 102 is driven upward in the optical axis direction against gravity, so the output torque required of the zoom actuator 311 is greater, and a larger actual power consumption is required than in the horizontal position. As shown in Figure 6(a), the normal actual power consumption of the zoom actuator 311 in the vertical position is, for example, 1.0 W, and the power upper limit value is set to 1.0 W.

[0054] However, by adding the 0.5 W of surplus power secured by the interchangeable lens 100 to the upper power limit of the zoom actuator 311, the upper power limit can be increased to 1.5 W. As a result, even if the actual power usage increases to, for example, 1.4 W by driving the zoom actuator 311 at a higher speed than usual, the zoom actuator 311 can be driven satisfactorily. Furthermore, when the ambient temperature rises from room temperature to a high temperature, friction increases due to hardening of grease inside the interchangeable lens 100 and the adapter 300 and expansion of parts, and the like, which may result in the actual power usage increasing compared to room temperature. Even in this case, the zoom actuator 311 can be driven satisfactorily as long as the actual power usage does not exceed 1.5 W.

[0055] In this way, by distributing the surplus power secured by the interchangeable lens 100 to the adapter 300, the zoom drive performance of the adapter 300 can be maintained or improved without increasing the power supply from the camera body 200.

[0056] In FIG. 6(b), because the interchangeable lens 100 does not have sufficient surplus power, the upper power limit of the zoom actuator 311 is 1.0 W. This may prevent the zoom actuator 311 from being driven at a sufficiently high speed or from being driven satisfactorily at high temperatures.

[0057] The flowchart in FIG. 7 shows the power upper limit setting process (control method) that is executed by the lens CPU 114 (power upper limit setting unit 122) as a computer in accordance with a program.

[0058] In step S101, the lens CPU 114 detects (acquires) the attitude through the attitude detection unit 123.

[0059] Next, in step S102, the lens CPU 114 acquires, via communication, the temperature detected by the temperature sensor 314 in the adapter 300. The attitude detection unit and temperature sensor may be provided in any of the interchangeable lens 100, the camera body 200, or the adapter 300, as long as the lens CPU 114 can acquire the detected attitude and temperature.

[0060] Next, in step S103, the lens CPU 114 sets the total value of the power upper limit values ​​for the anti-vibration actuator 110 and the focus actuator 112 and the power upper limit value for each actuator based on the posture detection results and temperature detection results acquired in steps S101 and S102. At this time, if the adapter 300 is attached to the interchangeable lens 100, the lens CPU 114 may also set the power upper limit value for the zoom actuator 311. Specific power upper limit value setting is as described using FIGS. 5(a), 5(b), and 6(a). More specifically, table data indicating power upper limit values ​​corresponding to postures and temperatures is prepared in advance. Then, the power upper limit value corresponding to the acquired posture and temperature is read from the table data and set. It is desirable that the power upper limit values ​​corresponding to postures in the table data include not only values ​​corresponding to the horizontal posture and the vertical posture, but also values ​​corresponding to one or more intermediate postures between the horizontal posture and the vertical posture (such as a diagonally upward posture). Furthermore, the power upper limit value corresponding to an intermediate posture may be calculated by interpolation using the power upper limit values ​​corresponding to the horizontal posture and the vertical posture.

[0061] Furthermore, if there is surplus power as a difference between the total value of the set power upper limit values ​​and the power supplied from the camera body 200, the lens CPU 114 sets the distribution of the surplus power (for example, allocation to the adapter 300).

[0062] Next, in step S104, the lens CPU 114 determines whether or not there has been a change in the attitude acquired via the attitude detection unit 123. If there has been a change in the attitude, the process of step S106 is performed, and if there has been no change in the attitude, the determination of step S104 is repeated.

[0063] In step S105, the lens CPU 114 determines whether or not there has been a change in the temperature acquired from the adapter 300. If the temperature has changed, the lens CPU 114 performs the process of step S106, and if the temperature has not changed, the lens CPU 114 performs the process of step S107.

[0064] In step S106, the lens CPU 114 changes the upper power limit set in step S103 to a new upper power limit according to the changed attitude and temperature, and then performs the process of step S108.

[0065] On the other hand, in step S107, the lens CPU 114 changes the upper power limit set in step S103 to a power limit according to the changed attitude, and then performs the process of step S108.

[0066] In step S108, the lens CPU 114 sets the allocation of surplus power, which is the difference between the total value of the power upper limit values ​​changed in step S106 or step S107 and the power supplied from the camera body 200. Then, the determination in step S04 is performed again.

[0067] As described above, in the lens apparatus 100 of this embodiment, the upper power limits and the distribution of surplus power for the anti-vibration actuator 110 and the focus actuator 112 are appropriately set in accordance with the attitude and temperature. This allows the lens apparatus 100 and the adapter 300 to use the limited power supplied from the camera body 200 effectively.

[0068] Note that in this embodiment, the case where upper power limits are set for the anti-vibration actuator 110 and the focus actuator 112 has been described. However, as long as there are two actuators in which the actual power usage of one increases and the actual power usage of the other decreases in response to changes in posture, the setting of upper power limits and allocation of surplus power as described in this embodiment may be performed for any of the two actuators. Also, as described above, if power is supplied to the interchangeable lens 100 from an external power source other than the camera body 200, surplus power may be generated by setting a power limit for the total value of power supplied from the camera body 200 and the external power source, or for power supplied only from the external power source.

[0069] Furthermore, the surplus power secured in the interchangeable lens 100 may be distributed to the camera body 200, rather than to other operating parts other than the anti-vibration actuator 110 and the focus actuator 112 within the interchangeable lens 100 or to the adapter 300. Specifically, the lens CPU 114 may send information about the surplus power to the camera CPU 206, thereby enabling the camera CPU 206 to select high-resolution imaging that uses more power or to increase the frame rate. Furthermore, an imaging mode that requires more power may be added to the types of imaging modes that can be selected.

[0070] Furthermore, the power upper limit setting process described in the above embodiment may be performed in an adapter that receives power supply from at least one of the interchangeable lens and the external power supply to drive the first and second drive means.

[0071] The above embodiment includes the following configurations.

[0072] (Configuration 1) An accessory for use with an imaging device, comprising: a first driving means for driving the first movable member; second driving means for driving the second movable member; a control means for controlling the power used for driving by the first and second driving means; When the attitude of the accessory changes from the first attitude to the second attitude, the power used for driving one of the first and second driving means increases and the power used for driving the other of the first and second driving means decreases; The accessory is characterized in that the control means changes the upper limit of the power available for driving by the first and second driving means in accordance with the attitude. (Configuration 2) 2. The accessory according to configuration 1, wherein the total value of the electric power used to drive the first and second driving means changes in accordance with the change in the posture. (Configuration 3) the first driving means drives the first movable member in a first direction; The accessory described in configuration 1 or 2, characterized in that the second driving means drives the second movable member in a second direction perpendicular to the first direction. (Configuration 4) 4. The accessory according to any one of configurations 1 to 3, wherein the control means changes the upper limit of the electric power used for driving by the first and second driving means. (Configuration 5) An accessory described in any one of configurations 1 to 4, characterized in that the control means changes the upper limit value as a total value for the first and second drive means depending on the posture detection result. (Configuration 6) 6. The accessory according to any one of configurations 1 to 5, wherein the control means changes the upper limit value in accordance with the detected temperature. (Configuration 7) The accessory described in any one of configurations 1 to 6, characterized in that the control means allocates surplus power generated by lowering the upper limit value of the power supplied from at least one of the imaging device and an external power source as power usable by other components within the accessory that are different from the first and second driving means. (Configuration 8) When another accessory is attached to the accessory, The accessory described in any one of configurations 1 to 7, characterized in that the control means supplies surplus power generated by lowering the upper limit value for power supplied from at least one of the imaging device and an external power source to the other accessory. (Configuration 9) The accessory described in any one of configurations 1 to 8, characterized in that the accessory is at least one of a lens device that is detachably attached to the imaging device and an adapter that is detachably attached to the lens device.

[0073] (Other Examples) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the 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 realizes one or more functions.

[0074] The embodiments described above are merely representative examples, and various modifications and alterations are possible to each embodiment when implementing the present invention. [Explanation of symbols]

[0075] 100 Interchangeable lenses (lens devices) 300 adapter 114 Lens CPU 122 Power upper limit setting unit 123 Attitude detection unit

Claims

1. An accessory for use with an imaging device, comprising: a first driving means for driving the first movable member; second driving means for driving the second movable member; a control means for controlling the power used for driving by the first and second driving means; When the attitude of the accessory changes from the first attitude to the second attitude, the power used for driving by one of the first and second driving means increases and the power used for driving by the other of the first and second driving means decreases; The accessory is characterized in that the control means changes the upper limit of the electric power available for driving by the first and second driving means in accordance with the attitude.

2. 2. The accessory according to claim 1, wherein the total value of the electric power used to drive the first and second driving means changes in accordance with the change in the attitude.

3. the first driving means drives the first movable member in a first direction; 2. The accessory according to claim 1, wherein the second driving means drives the second movable member in a second direction perpendicular to the first direction.

4. 2. The accessory according to claim 1, wherein the control means changes upper limits of the electric power used for driving by the first and second driving means.

5. 2. The accessory according to claim 1, wherein the control means changes the upper limit value as a total value for the first and second driving means in accordance with the detected posture.

6. 2. The accessory according to claim 1, wherein the control means changes the upper limit value in response to a detected temperature.

7. The accessory described in claim 1, characterized in that the control means allocates surplus power generated by lowering the upper limit value of the power supplied from at least one of the imaging device and an external power source as power usable by other components within the accessory other than the first and second driving means.

8. When another accessory is attached to the accessory, The accessory according to claim 1 , wherein the control means supplies surplus power generated by lowering the upper limit of power supplied from at least one of the imaging device and an external power source to the other accessory.

9. 2. The accessory according to claim 1, wherein the accessory is at least one of a lens device detachably attached to the imaging device and an adapter detachably attached to the lens device.

10. A control method for an accessory used together with an imaging device, the accessory having a first driving means for driving a first movable member and a second driving means for driving a second movable member, the method comprising: When the attitude of the accessory changes from the first attitude to the second attitude, the power used for driving one of the first and second driving means increases and the power used for driving the other decreases, acquiring a posture of the accessory; and changing the upper limit of the electric power available for driving by the first and second driving means in accordance with the attitude.

11. A program causing a computer to execute a process according to the control method of claim 10.

Images