Control of multiple lens devices

Abstract

This system provides a shooting system that matches the operability of zoom, focus, and aperture based on the differences in optical characteristics between lens devices. [Solution] The control device for the imaging system is an imaging system comprising a plurality of lens devices having drive units for driving optical elements for changing optical characteristics, and an operating device for operating the drive unit of at least one of the plurality of lens devices, wherein the control device has a command value calculation unit that calculates a drive command value for the drive unit of the operated lens device operated by the operating device based on the amount of operation of the operating device, a first optical information processing unit that calculates a first amount of change in optical characteristics when the drive command value is input to the operated lens device, and a second optical information processing unit that calculates a second amount of change in optical characteristics when the drive command value is input to a reference lens device other than the operated lens device, and a command value changing unit that changes the drive command value so that at least a part of the first amount of change and the second amount of change are the same.

Description

Technical Field

[0001] The present invention relates to a control device for a photographing system that controls lens driving when photographing using a plurality of lens devices, a lens device, and an operation member.

Background Art

[0002] For example, when photographing in a studio, a live venue, a circuit venue, etc., it is common to install a plurality of cameras equipped with lens devices capable of driving drive units for changing optical characteristics such as zoom, focus, and aperture, and perform photographing. In camera operation when photographing using a plurality of cameras like this, when performing remote operation, one operator may operate a plurality of cameras. At that time, depending on the model of the lens device mounted on the camera, the zoom position, the focus position, the aperture position, etc., the zoom magnification variation, the focus sensitivity, the closed position of the aperture mechanism, etc. may change.

[0003] For example, when operating two lens devices with different zoom magnifications, if the operation device for zoom is operated by a only, the magnification of one lens device changes by A1, and the magnification of the other lens device changes by A2.

[0004] Similarly, when operating two lens devices with different focus sensitivities, if the operation device for focus is operated by b only, the focus object distance of one lens changes by B1, and the focus object distance of the other lens device changes by B2.

[0005] Also, when operating two lens devices with different aperture open and closed positions, for example, in order to drive from the closed state to a predetermined F value, one lens needs to operate the operation device by c1 only, and the other lens device needs to operate the operation member by c2 only.

[0006] In such a case, when one operator operates a plurality of lens devices, it is difficult to drive the zoom, focus, and aperture as intended by the operator.

[0007] Furthermore, increasing the number of lens devices makes the system even more complex and difficult to operate. Therefore, it is desirable to standardize the operability of multiple lens devices. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Patent No. 7028349 specification

[0009] Patent Document 1 describes a method for keeping the zoom magnification fluctuation constant across multiple cameras in response to the amount of operation of an operating device. However, Patent Document 1 does not mention that keeping the zoom magnification fluctuation constant prevents the zoom drive speed from reaching the maximum zoom drive speed inherent in the lens device, nor does it address the operability of focus or aperture. [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] As mentioned above, in conventional shooting systems, when one operator controls multiple lens devices, there is a problem in that zoom, focus, and aperture control is difficult due to differences in the optical characteristics between the lens devices.

[0011] The object of the present invention is to provide a shooting system in which a single operator can operate a drive unit that changes the optical characteristics of multiple lens devices, even if there are differences in the optical characteristics of the multiple lens devices, with a similar feel of operation. [Means for solving the problem]

[0012] To solve the above problems, the present invention provides a control device for a shooting system, comprising a plurality of lens devices having drive units for driving optical members for changing optical characteristics, and an operating device for operating the drive unit of at least one of the plurality of lens devices, wherein the control device for the shooting system comprises a command value calculation unit that calculates a drive command value for the drive unit of the operated lens device operated by the operating device based on the amount of operation of the operating device, a first optical information processing unit that calculates a first amount of variation of the optical characteristics when the drive command value is input to the operated lens device, and a second optical information processing unit that calculates a second amount of variation of the optical characteristics when the drive command value is input to a reference lens device other than the operated lens device, and a command value changing unit that changes the drive command value so that at least a part of the first amount of variation and the second amount of variation are the same. [Effects of the Invention]

[0013] According to the present invention, when a single operator controls a drive unit that changes the optical characteristics of multiple lens devices, it is possible to provide a shooting system that can be operated with a similar feel even if there are differences in the optical characteristics of the multiple lens devices. [Brief explanation of the drawing]

[0014] [Figure 1] This is a block diagram of the imaging system of Example 1 of the first embodiment. [Figure 2] This figure shows the zoom speed command and the fluctuation curve of the zoom magnification in the first embodiment. [Figure 3] This is a flowchart for changing the drive command value in Example 1 of the first embodiment. [Figure 4] This is a block diagram of the imaging system of Example 2 of the first embodiment. [Figure 5] This figure shows the focus demand operation position, focus lens position, and object distance in the first embodiment. [Figure 6] This is a flowchart for changing the drive command value in Example 2 of the first embodiment. [Figure 7]It is a block diagram showing the configuration of an imaging device including a camera and a camera accessory according to the second embodiment. [Figure 8] It is a diagram showing an example of lens information displayed on the camera screen according to the second embodiment. [Figure 9] It is a flowchart showing the flow of the camera according to the second embodiment receiving the amount of change in back focus from an adapter and correcting the lens display information displayed on the camera screen. [Figure 10] It is a diagram showing an example of correcting the lens display information displayed on the camera screen due to the change in back focus according to the second embodiment. [Figure 11] It is a flowchart showing the flow of the camera according to the second embodiment receiving the adjustment amount of back focus performed by a camera accessory or the camera and correcting the lens display information displayed on the camera screen. [Figure 12] It is a diagram showing an example of correcting the lens display information displaying the adjustment amount of back focus on the camera screen according to the second embodiment. [Figure 13] It is a flowchart showing the flow of the adapter according to the second embodiment correcting the lens display information based on the amount of change in back focus. [Figure 14] It is a configuration diagram of a lens-exchangeable camera according to the third embodiment. [Figure 15] It is a diagram showing the sensor structure for detecting the position of a variable zoom lens according to the third embodiment. [Figure 16] It is a block diagram related to determining the driving range of a focus lens according to the third embodiment. [Figure 17] It is a diagram showing an overview of the output signal of a zoom position detection unit according to the third embodiment. [Figure 18] It is a flowchart related to the position calculation of a zoom position detection unit according to the third embodiment. [Figure 19] It is a diagram showing the output signal after signal processing of a zoom position detection unit according to the third embodiment. [Figure 20] It is a diagram showing a vernier signal of a zoom position detection unit according to the third embodiment. [Figure 21]This figure shows the synchronous calculation process of the zoom position detection unit in the third embodiment. [Figure 22] This is a flowchart for determining the zoom range and focus drive range according to Example 1 of the third embodiment. [Figure 23] This figure shows the relationship between the zoom position and the focus position in the third embodiment. [Figure 24] This is a flowchart of the zoom position update and focus drive range update according to Example 2 of the third embodiment. [Figure 25] This is a flowchart of focus control based on focus position and drive range according to Example 2 of the third embodiment. [Figure 26] This is a flowchart of the zoom range update and focus drive range update according to Example 3 of the third embodiment. [Modes for carrying out the invention]

[0015] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Figure 1 is a block diagram relating to an embodiment of the present invention.

[0016] <First Embodiment> [Example 1]

[0017] The first embodiment of the first model will be described below with reference to Figures 1 to 3.

[0018] For the sake of simplicity in this embodiment, the lens device consists of two components, lens device a and lens device b, and the operator will selectively operate lens device a and lens device b.

[0019] Furthermore, this embodiment describes the process when lens device a is selected and lens device b is selected, that is, when the target lens device to be operated (hereinafter referred to as the operated lens device) changes from lens device a to lens device b.

[0020] Figure 1 shows an example of the configuration of the imaging system related to this matter.

[0021] In the figure, the imaging system 10 is configured to include lens devices 200a and 200b, a control device 300 that calculates drive command values ​​for driving the optical elements of the lens devices 200a and 200b, an operating device 100 which is an input unit for the lens operator, and a lens selection device 101.

[0022] Here, lens device 200b is a lens device that can zoom to a greater zoom magnification than lens device 200a.

[0023] In the following, when different lens devices are to be distinguished, they will be indicated with a suffix such as "200a" or "200b," and when they are not to be distinguished, they will be indicated without a suffix, such as "200."

[0024] In this embodiment, the movable optical element 203 constituting the lens device 200 is a zoom lens, and the motor 204 is a motor for driving the zoom lens. The drive control unit 205 may be a drive circuit including a CPU that controls the rotation of the motor 204.

[0025] Furthermore, the detection unit 202 detects the position of the zoom lens.

[0026] The optical information storage unit 201 is a storage unit that stores optical information dependent on the model of the lens device 200, and may, for example, be information regarding the magnification of the lens device 200 model, or table data representing the variation in zoom magnification with respect to the zoom lens position.

[0027] The operating device 100 is an operating device for giving speed commands to the zoom lens, and could be, for example, a zoom demand, which is a common zoom operating device for broadcast lenses.

[0028] The lens selection device 101 is an operating device for selecting whether the object to be operated by the operating device 100 (hereinafter referred to as the operated lens device) is lens device 200a or lens device 200b.

[0029] The control device 300 includes a command value calculation unit 301, an operated lens selection unit 302, a first optical information processing unit 303, a second optical information processing unit 304, and a command value modification unit 305.

[0030] The command value calculation unit 301 calculates a first drive command value for driving the movable optical element 203 (zoom lens in this embodiment) based on the amount of operation of the operating device 100. The first drive command value may be a speed command value for driving the zoom lens.

[0031] The operated lens selection unit 302 selects whether the operated lens device is lens device 200a or 200b based on the selection result of the lens selection device 101.

[0032] If the selected result is the lens device 200a, that is, the reference lens device described later, the first drive command value is output to the drive control unit 205a.

[0033] The drive control unit 205a drives the motor 204a and drives the optical member 203a based on the first drive command value and the detection result of the zoom lens position by the detection unit.

[0034] Furthermore, if the selected result is lens device 200b, the first drive command value is output to the first optical information processing unit 303, the second optical information processing unit 304, and the command value modification unit 305.

[0035] The first optical information processing unit calculates a first variation, which is the optical characteristic when the lens device 200a is driven by a first drive command value, based on the optical information stored in the optical information storage unit 201a and the detection result of the detection unit 202a.

[0036] The second optical information processing unit calculates a second variation, which is the optical characteristic when the lens device 200b is driven by the first drive command value, based on the optical information stored in the optical information storage unit 201b and the detection result from the detection unit 202b.

[0037] In this embodiment, the first and second fluctuation amounts are defined as the fluctuation speed of the zoom magnification of each lens device.

[0038] The command value changing unit 305 changes the first drive command value to the second drive command value based on the first and second fluctuation amounts and outputs it to the drive control unit 205b.

[0039] The drive control unit 205b drives the motor 204b and drives the optical member 203b based on the second drive command value and the detection result of the zoom lens position by the detection unit.

[0040] Figure 2 shows an example of a command value change performed in the command value change unit 305.

[0041] Figures (2-1) and (2-2) represent the zoom speed command values ​​corresponding to the operating amounts of the operating devices for lens device a and lens device b, respectively, while figures (2-3) and (2-4) represent the magnification fluctuation speed when the zoom lens is driven by the speed command values.

[0042] The speed command curve a shown in (2-1) is a curve that represents the zoom drive speed with respect to the manipulated amount when the zoom lens of lens device a is driven by the first drive command value.

[0043] The magnification fluctuation curve a shown in (2-2) is a curve that represents the magnification fluctuation speed with respect to the manipulated amount when the zoom lens of lens device a is driven by the first drive command value.

[0044] The dashed speed command curve b1 shown in (2-3) is a curve that represents the zoom speed command value in relation to the manipulated amount when the zoom lens of lens device b is driven by the first drive command value.

[0045] The solid speed command curve b2 represents the zoom drive speed in relation to the manipulated amount when the zoom lens of lens device b is driven by the second drive command value.

[0046] The dashed magnification fluctuation curve b1 shown in (2-4) represents the magnification fluctuation rate with respect to the manipulated amount when the zoom lens of lens device b is driven by the first drive command value.

[0047] The solid line magnification fluctuation curve b2 represents the magnification fluctuation rate with respect to the manipulated amount when the zoom lens of lens device b is driven by the second drive command value.

[0048] The zoom drive will be explained, focusing on (2-1) and (2-2) shown for lens device a.

[0049] Both the horizontal axis in (2-1) and (2-2) shows the amount of operation of the control device 100. When the control device is operated to its maximum value (Max), the zoom speed command value Vd becomes the maximum (Vdmax), and the magnification fluctuation speed Va also becomes the maximum Va3 for lens device a.

[0050] Furthermore, when a predetermined control input α is given, the zoom speed command value of lens device a becomes Vd2, and the magnification change speed becomes Va1.

[0051] We will now explain the zoom drive when focusing on (2-3) and (2-4) shown for lens device b.

[0052] First, let's explain zoom drive when driven by the speed command curve b1 and the magnification variation curve b1.

[0053] When the maximum amount of movement is applied, the zoom lens drive speed Vd becomes maximum (Vdmax), and the magnification change speed Va becomes the maximum Va4 for lens device b.

[0054] Furthermore, when a predetermined control amount α is input, the zoom drive speed of lens device b becomes Vd2, and when driven by the magnification variation curve b1, the magnification variation speed becomes Va2.

[0055] Thus, when the same operator uses lenses with different zoom magnifications, even if the same amount of input is used, the amount of change in magnification will differ, which can lead to errors or discomfort during operation.

[0056] In particular, when performing zoom operations in the low to medium speed range, such differences can strongly manifest as a sense of unnaturalness in operation.

[0057] Therefore, if the same operation input is given to lens device a and lens device b, and the magnification changes at the same rate of change, the aforementioned difference will be eliminated.

[0058] However, if lens device b, which has a large zoom ratio for all manipulated amounts, changes its magnification at the same rate as lens device a, which has a small zoom ratio, then, for example, when the manipulated amount Max is input, lens device b cannot be driven at the maximum magnification change rate of Va4.

[0059] Next, we will explain zoom drive when the speed command curve b1 and magnification variation curve b1 are changed to the speed command curve b2 and magnification variation curve b2.

[0060] In the command value changing section of lens device b, the zoom speed command value is changed to Vd1 so that the magnification fluctuation speed for manipulated amount α becomes Va1, which is the magnification fluctuation speed when manipulated amount α is input to lens device a.

[0061] If an input variable β less than or equal to the input variable α is input, the zoom speed command value is changed to match the magnification fluctuation speed when input variable β is input to lens device a, similar to when input variable α is input.

[0062] In other words, the magnification variation speed is the same for lens device a and lens device b when an input variable less than or equal to the input variable α is used.

[0063] Furthermore, if the control input is Max, the zoom speed command value for lens device b will be Vdmax.

[0064] The zoom speed command value between the manipulated variable α and Max can be obtained, for example, by linear interpolation based on the zoom speed command value of representative values ​​of the two or more manipulated variables.

[0065] As described above, by calculating the second drive command value according to the speed command curve b2, the magnification fluctuation speed of the operated lens device changes as shown in the magnification fluctuation curve b2.

[0066] As a result, the difference in magnification change speed relative to the amount of movement is clearly evident, eliminating the unnatural feeling of operation in the low to medium speed range, while enabling zoom operation without sacrificing speed performance in the medium to high speed range.

[0067] Figure 3 illustrates the process flow for changing the first drive command value of a zoom lens to the second drive command value.

[0068] In the figure, first, in step S101, it is determined whether there is an instruction from the operating device 100 to start the process of generating a command value. If such an instruction is given, the process proceeds to step S102; otherwise, the process in step S101 is repeated.

[0069] In step S102, a first drive command value is calculated from the operating amount of the operating device 100 to determine the drive amount of the optical member 203.

[0070] In step S103, a determination is made as to whether to match the zoom drive of the operated lens device to that of the reference lens device. If it is not to match the reference lens device, the process proceeds to step S108; if it is to match the reference lens device, the process proceeds to S103.

[0071] In step S104, it is determined whether the lens device to be operated is a reference lens device. If the lens device to be operated is a reference lens device, the process proceeds to step S108; otherwise, the process proceeds to step S105.

[0072] In step S105, the magnification change speed of the operated lens device is calculated from the first drive command value, the optical information of the operated lens device, and the zoom lens position, and the process proceeds to step S106.

[0073] In step S106, the magnification fluctuation speed of the reference lens device when the first drive command value is input to the reference lens device is calculated from the first drive command value, the optical information of the reference lens device, and the zoom lens position, and the process proceeds to step S107.

[0074] In step S107, the first drive command value is changed based on the magnification variation speed of the operated lens device and the reference lens device, and the process proceeds to step S108.

[0075] In step S108, the motor is driven based on the input drive command value.

[0076] Furthermore, in the shooting system of this embodiment, multiple lens devices to be operated are selected by the lens selection device 101 and operated by a single operating device 100. However, the present invention is effective for shooting systems in which a single operator selectively operates multiple lens devices, and is not limited to this operating configuration. For example, there may be a shooting system in which multiple operating devices are assigned to each of the multiple lens devices, and the operator selectively operates them.

[0077] Furthermore, in this embodiment, the reference lens device is set from the lens device configured in the imaging system, but it may also be a lens device not configured in this imaging system or a virtual lens device.

[0078] Furthermore, in this embodiment, the control device of the imaging system performs the calculation of the first drive command value and the modification of the first drive command value, i.e., the calculation of the second drive command value. However, some or all of these processes may be performed by the operating device or lens device.

[0079] Furthermore, although the optical element 203 is described as a zoom lens in this embodiment, it is not limited to a zoom lens. Since the amount of operation of the operating device 100 in this embodiment provides a speed command value, it may also be a focus lens or aperture mechanism driven by the speed command, or a depth of field adjustment unit. [Example 2]

[0080] The second embodiment of the first embodiment will be described below with reference to Figures 4 to 6.

[0081] Figure 4 shows an example of the configuration of the imaging system related to Example 2. Figure 4 will be explained by focusing only on the differences from Figure 1.

[0082] In this embodiment, as in Embodiment 1, we will explain the process when lens device a is selected and then lens device b is selected, that is, when the operated lens device changes from lens device a to lens device b.

[0083] First, in this embodiment, the optical element 203 is assumed to be a focusing lens.

[0084] Lens device a and lens device b are assumed to have a difference in the amount of image plane movement of the imaging optical system in relation to the amount of movement of the focusing lens (hereinafter referred to as focus sensitivity).

[0085] The operating device 100 is an operating device for giving a target position command to the focus lens, and may be, for example, a focus demand, which is a common focus operating device for broadcast lenses.

[0086] In this embodiment, the focus demand is such that there is no operating end in the rotation angle of the operating knob, and the operating knob can continue to rotate.

[0087] Furthermore, the optical information storage unit 201 has table data relating to the distance to the focused object based on the zoom lens position and focus lens position of each lens device.

[0088] The optical component 206 is a zoom lens, and the second detection unit 207 detects the position of the zoom lens.

[0089] Furthermore, the first drive command value calculated by the command value calculation unit 301 is a command value related to the target position, the optical element 203 (focus lens) is driven based on the position command value, and the first detection unit 202 detects the position of the focus lens. The second detection unit 207 detects the position of the optical element 206, which is a zoom lens.

[0090] Furthermore, the second drive command value calculated by the command value modification unit 305 is a command value related to the target position, similar to the first drive command value.

[0091] The first and second fluctuation amounts of optical characteristics calculated by the first optical information processing unit 303 and the second optical information processing unit 304 are information relating to the focus lens position relative to the operating position of the operating device, and are calculated based on the optical information storage unit 201, the first detection unit 202, and the second detection unit 207.

[0092] The first and second fluctuation amounts are stored in the first fluctuation amount storage unit 306 and the second fluctuation amount storage unit 307, respectively.

[0093] Furthermore, the selection result of the operated lens selection unit 302 is passed not only to the command value change unit, but also to the first optical information processing unit 303 and the second optical information processing unit 304. Based on the selection result, the first optical information processing unit and the second optical information processing unit decide whether to pass the first variation amount or the second variation amount to the first variation amount storage unit 306 or the second variation amount storage unit 307.

[0094] For example, the first or second variation amount is stored only when the selection result changes, that is, when the operated lens is switched.

[0095] The command value changing unit changes the first drive command value based on the first or second fluctuation amount.

[0096] Figure 5 illustrates an example of how the drive command value is changed in the command value changing unit 305.

[0097] (5-1) is a diagram showing an example of the change in the focus lens position with respect to the operating position of the focus demand of lens devices a and b when driven with the first drive command value, and (5-3) is a diagram showing an example of the change in the focus lens position with respect to the operating position of the focus demand of lens devices a and b when driven with the second drive command value.

[0098] The position command curves a and b1 in (5-1) represent the trajectories of the target position of the focusing lens relative to the operating positions of lens devices a and b, and lens devices a and b follow similar trajectories.

[0099] (5-2) is similar to (5-1) in that it shows the change in the object distance at focus when the focus demand is operated, with focus curve a representing the trajectory in lens device a and focus curve b1 representing the trajectory in lens device b.

[0100] Here, the slope of the focus curve represents the focus sensitivity.

[0101] From (5-1) and (5-2), it can be seen that even though the focusing lens moves along the same trajectory, there is a difference in the movement of the object distance, i.e., the sensitivity to focus, between lens devices a and b.

[0102] Such differences can occur, for example, depending on the lens model or the zoom lens position.

[0103] The relationship between the (operating position of the focus demand and the position of the focus lens) for each lens device is as follows: Lens device a is located at (X1, posi1), and lens device b is located at (X2, posi2).

[0104] When the focus position of each lens device is in this state, switching the operated lens device from lens device a to lens device b results in a large difference in focus sensitivity, making it particularly difficult to focus immediately after the switch.

[0105] Therefore, when switching the operated lens device from lens device a to lens device b, the position command curve b1 is changed to position command curve b2 and the focus curve b1 is changed to focus curve b2, for example, as in (5-3) and (5-4).

[0106] The focus curve b2 in (5-4) is calculated using the focus lens positions of lens devices a and b and focus curve a.

[0107] An example of a specific method for calculating the focus curve b2 is explained below.

[0108] First, the difference between the operating position X1 of lens device a and the operating position Xbase where the object distance to obj3 is determined by focus curve a is added to the operating position of focus curve a. In other words, focus curve a is shifted to the right by X1-Xbase. This allows the focus curves for obj2 to obj5 to be calculated.

[0109] Furthermore, obj1 to obj2 are determined by calculating the focus curve assuming that lens device a is driven to the focus lens position corresponding to obj1.

[0110] The focus curves of obj1 to obj2 can be calculated, for example, by determining an approximation formula using the focus curves of obj2 to obj5 and performing extrapolation interpolation, and in the case of X0(b), it can be obj1.

[0111] As described above, the focus curve b2 from obj1 to obf5 is calculated.

[0112] Then, the position command curve b2 is determined by calculating the focus lens position such that the object distance changes, as shown in focus curve b2, from the table data related to the focus object distance of lens device b.

[0113] The method for determining the above position command curve b2 is, for example, to select the focus lens position posi2, which is the closest object distance obj3 to the operation position X1, from the table data, and to determine it as the focus lens position for X1. A similar process is performed for multiple other operation positions, and the operation positions between the processed multiple positions can be calculated, for example, by performing linear interpolation of the determination results for each position.

[0114] By switching as described above, the focus sensitivity can be adjusted when the operated lens device is switched, allowing for smooth focusing even immediately after the switch.

[0115] Figure 6 illustrates the process flow for changing the first drive command value of a zoom lens to the second drive command value.

[0116] In the figure, first, in step S201, it is determined whether there is an instruction from the operating device 100 to start the process of generating a command value. If such an instruction is given, the process proceeds to step S102; otherwise, the process in step S201 is repeated.

[0117] In step S202, the first drive command value, which is the target position of the optical element 203, is calculated from the operating position of the operating device 100.

[0118] In step S203, a determination is made as to whether to match the focus drive of the operated lens device to that of the reference lens device. If it is not to match the reference lens device, the process proceeds to S208; if it is to match the reference lens device, the process proceeds to S203.

[0119] In step S204, it is determined whether the lens device to be operated is a reference lens device. If the lens device to be operated is a reference lens device, the process proceeds to step S208; otherwise, the process proceeds to step S205.

[0120] In step S205, it is determined whether to change the position command curve. For example, if the focus sensitivity changes discontinuously, such as immediately after the operated lens device is switched, the position command curve is changed and the process proceeds to step S206. If the position command curve is not changed, the process proceeds to step S207.

[0121] In step S206, the position command curve that determines the command value of the focus lens position relative to the operating position of the operated lens device is changed, and the process proceeds to step S207.

[0122] In step S207, the second drive command value is calculated based on the first drive command value and the position command curve, and the process proceeds to step S208.

[0123] In step S208, the motor is driven based on the input drive command value.

[0124] Furthermore, although the optical element 203 is described as a focusing lens in this embodiment, it is not limited to a focusing lens. Since the amount of operation of the operating device 100 in this embodiment provides a position command value, it may also be a zoom lens or an aperture mechanism that adjusts the amount of light driven by a position command.

[0125] For example, when applied to a light intensity variation section using an aperture mechanism, the difference in aperture open and closed positions between the reference lens device and the operated lens device can result in an unnatural feeling during operation. Therefore, this unnatural feeling can be eliminated by making the amount of operation from a predetermined F-number to the open or closed position consistent for each lens.

[0126] <Second Embodiment> A second embodiment of the present invention will be described below with reference to the drawings.

[0127] Figure 7 is a block diagram showing an example of a configuration for realizing an imaging device according to the second embodiment.

[0128] The imaging device consists of an interchangeable lens 100, a camera 200, and an adapter 300.

[0129] First, let's explain the specific configuration of the interchangeable lens 100, camera 200, and adapter 300.

[0130] The interchangeable lens 100, adapter 300, and camera 200 are mechanically and electrically connected via a mount (not shown). The interchangeable lens 100 and adapter 300 receive power from the camera 200 via a power terminal (not shown) provided on the aforementioned mount. Using the power received from the camera 200, they control various actuators, the lens microcomputer (hereinafter referred to as lens microcontroller) 111, and the adapter microcomputer (hereinafter referred to as adapter microcontroller) 302, which will be described later. The camera 200 also communicates with the interchangeable lens 100 and adapter 300 via a communication terminal (not shown) provided on the aforementioned mount, and controls the interchangeable lens 100 and adapter 300 by sending control commands.

[0131] Next, the configuration of the camera 200 will be described. The camera 200 includes an image sensor 201, a signal processing circuit 202, a recording processing unit 203, a display unit 204, an operation unit 205, a camera microcomputer (hereinafter referred to as camera microcontroller) 206, a back focus control unit 207, and a back focus adjustment unit 208.

[0132] The image sensor 201 converts the subject image formed by the imaging optical system in the interchangeable lens 100 into an electrical signal (analog signal) through photoelectric conversion. An A / D conversion circuit (not shown) converts the analog signal from the image sensor 201 into a digital signal.

[0133] The signal processing circuit 202 performs various image processing operations on the digital signal from the A / D conversion circuit to generate a video signal. The signal processing circuit 202 also generates focus information, which indicates the contrast state of the subject image, i.e., the focal state of the imaging optical system, and luminance information, which represents the exposure state, from the video signal.

[0134] The signal processing circuit 202 outputs the video signal to the display unit 204, which displays the video signal as a live view image used for checking composition, focus, etc. Furthermore, the signal processing circuit 202 outputs the video signal to the recording processing unit 203, which stores the video signal as still images or moving image data in external memory or the like.

[0135] The camera microcontroller 206, acting as the camera control unit, controls the camera 200 in response to inputs such as the imaging instruction switch and various setting switches included in the operation unit 205. The camera microcontroller 206 controls the back focus control unit 207 in response to the input, driving the image sensor 201 or the back focus adjustment unit 208 to adjust the back focus. The camera microcontroller 206 also transmits control commands to the lens microcontroller 111 via the camera communication unit regarding the adjustment of the aperture unit 103, focus lens 105, and back focus control unit 110 according to brightness information. Furthermore, the camera microcontroller 206 transmits control commands to the adapter microcontroller 302 via the camera communication unit regarding the adjustment of the back focus control unit 301.

[0136] The image sensor 201 and the back focus adjustment unit 208 are movable in the optical axis direction shown by the dashed line in the figure, and their positions are detected using a position detection sensor, and the position data is output to the camera microcontroller 206. The back focus control unit 207 adjusts the back focus by outputting a drive signal from the camera microcontroller 206 to drive an actuator such as a stepping motor, thereby moving the back focus adjustment unit 112. Alternatively, the image sensor 201 and the back focus adjustment unit 208 may be designed to be manually adjustable without using actuators.

[0137] Next, the configuration of the interchangeable lens 100 will be described. The interchangeable lens 100 includes an imaging optical system, various control units that control various actuators that drive the imaging optical system or the back focus adjustment unit 112, an operating ring 110, and a lens microcontroller 111.

[0138] The lens microcontroller 111 is a control unit that controls the operation of each part within the interchangeable lens 100. The lens microcontroller 111 receives control commands transmitted from the camera 200 via the communication unit and receives requests to transmit lens data. The lens microcontroller 111 also performs lens control corresponding to the control commands and transmits lens data corresponding to the transmission request to the camera 200.

[0139] The lens microcontroller 111 responds to control commands by driving the aperture unit 103, the focus lens 105, and the back focus adjustment unit 112. This enables autofocus processing that controls the light intensity adjustment and focus adjustment operations of the aperture unit 103, the focus lens 105, and the back focus adjustment unit 112, as well as back focus adjustment.

[0140] Furthermore, the lens microcontroller 111 controls the focus adjustment operation by issuing commands to the focus lens control unit 109 in accordance with the amount of operation of the lens operation ring 110, thereby driving the focus lens 105. Here, the lens operation ring 110 may be configured to operate multiple control members depending on the settings.

[0141] The imaging optical system includes a field lens 101, a zoom lens 102 for variable magnification, an aperture unit 103 for adjusting the amount of light, an image shake correction lens 104, and a focus lens 105 for adjusting the focus.

[0142] The zoom lens 102 is movable in the optical axis direction, as shown by the dashed line in the figure, and is driven in the optical axis direction by the user operating a zoom operation ring connected to a zoom mechanism (not shown). This allows for zoom variation, where the focal length of the imaging optical system is changed by the movement of the zoom lens 102. The zoom lens position detection unit 106 detects the zoom lens position using a position detection sensor such as a variable resistor and outputs the position data as -. The output position data is used by the lens microcontroller 111 for control, such as the zoom tracking operation described later.

[0143] The aperture unit 103 is comprised of sensors such as aperture blades and Hall elements. The state of the aperture blades is detected by the aforementioned sensors and output to the lens microcontroller 111. The aperture control unit 107 outputs a drive signal based on a command from the lens microcontroller 111 to drive actuators such as stepping motors and voice coil motors. This allows the aperture unit 103 to adjust the amount of light.

[0144] The image shake correction lens 104 reduces image shake caused by camera shake, etc., by moving in a direction perpendicular to the optical axis of the imaging optical system. The image shake correction lens control unit 108 outputs a drive signal to drive the vibration damping actuator based on a command from the lens microcontroller 111 in response to shake detected by a shake sensor (not shown), such as a vibration gyroscope. This performs vibration damping processing that controls the shift operation of the image shake correction lens 104.

[0145] The focus lens 105 is movable in the optical axis direction shown by the dashed line in the figure. A position detection sensor such as a photointerrupter is used to detect the position of the focus lens 105, and the position data is output to the lens microcontroller 111. The focus lens control unit 109, based on a command from the lens microcontroller 111, outputs a drive signal to drive an actuator such as a stepping motor, thereby adjusting the focus by moving the focus lens 105. The focus lens 105 also corrects image plane fluctuations caused by the magnification change of the zoom lens 102.

[0146] The back focus adjustment unit 112 is movable in the optical axis direction shown by the dashed line in the figure. A position detection sensor such as a photointerrupter is used to detect the position of the back focus adjustment unit 112, and the position data is output to the lens microcontroller 111. The back focus control unit 110, in response to a command from the lens microcontroller 111, outputs a drive signal to drive an actuator such as a stepping motor, thereby adjusting the back focus by moving the back focus adjustment unit 112. Alternatively, the back focus adjustment unit 112 may be designed to be manually adjustable without using an actuator.

[0147] Next, the configuration of the adapter 300 will be described. The adapter 300 includes a back focus adjustment unit 303, a back focus control unit 301 that controls an actuator that drives the back focus adjustment unit 303, and an adapter microcontroller 302.

[0148] The back focus adjustment unit 301 is movable in the optical axis direction shown by the dashed line in the figure. A position detection sensor such as a photointerrupter is used to detect the position of the back focus adjustment unit 301, and the position data is output to the adapter microcontroller 302. The back focus control unit 301 adjusts the back focus by outputting a drive signal from the adapter microcontroller 302 to drive an actuator such as a stepping motor, thereby moving the back focus adjustment unit 301. Alternatively, the back focus adjustment unit 301 may be designed to be manually adjustable without using an actuator.

[0149] Figure 7 shows an example camera system in which one adapter 300 is connected between the camera 200 and the interchangeable lens 100, but multiple adapters may be linked together and connected between the camera 200 and the interchangeable lens 100. Also, although the interchangeable lens 100, camera 200 and adapter 300 are shown with a back focus adjustment section and a back focus control section, flange back may be used instead of back focus. [Example 1]

[0150] Next, Example 1 of the second embodiment will be described.

[0151] In Example 1, the camera microcontroller 206 receives information on the amount of back focus change from the adapter microcontroller 302 and describes a method for correcting the information on the lens 100 displayed on the display unit 204.

[0152] Figure 8 shows an example where the camera microcontroller 206 receives subject distance information, magnification information, focal length information, and the position of the focus lens 105 from the lens microcontroller 111 and displays them on the display unit 204. As shown in Figure 8, by displaying the subject distance information, magnification information, focal length information, and the position of the focus lens 105 on a bar, the user can check at what distance the image will be in focus and how large the image will be. However, when an adapter or the like is attached and the back focus is changed, the subject distance at which the image is in focus and the magnification will change.

[0153] The following describes the process by which the camera microcontroller 206 acquires information from the lens 100 and adapter 300 and corrects the information of the lens 100 displayed on the display unit 204, referring to the flowchart in Figure 9.

[0154] The process begins from step S301, when power is turned on to the camera 200.

[0155] Next, in step S302, the camera 200 supplies power to the lens 100.

[0156] Next, in step S303, the camera microcontroller 206 and the lens microcontroller 111 perform ID communication.

[0157] Next, in step S304, the adapter microcontroller 302 transmits information about the amount of change in back focus to the camera microcontroller 206.

[0158] Next, in step S305, the lens microcontroller 111 transmits lens display information to the camera microcontroller 206 for display on the display unit 204.

[0159] Next, in step S306, the camera microcontroller 206 corrects the lens display information received in step S305 based on the information on the amount of change in back focus received in step S304.

[0160] Next, in step S307, the camera microcontroller 206 displays the lens display information corrected in step S306 on the display unit 204 and terminates the process.

[0161] Figure 10 shows an example of the display shown in Figure 8, corrected based on information about the change in back focus and displayed on the display unit 204. By correcting and displaying the subject distance information and magnification information in this way, the user can correctly confirm at what distance the image will be in focus and how much larger the image can be captured, even if the back focus changes.

[0162] In the flowchart in Figure 9, the correction of the lens display information was performed based on the change in back focus, but the correction may also be performed using the adapter's ID information. Alternatively, the correction of the lens display information may be performed based on the change in flange back instead of back focus.

[0163] In the example shown in Figure 10, the lens display information corrected by the camera microcontroller 206 was subject distance information and magnification information, but information such as focal length, exposure, and light intensity may also be corrected.

[0164] If multiple adapters are attached, the camera microcontroller 206 may sum up the changes in back focus of all attached adapters and correct the lens display information. [Example 2]

[0165] Next, Example 2 of the second embodiment will be described.

[0166] In Example 2, we will explain how to correct the lens display information when the camera 200, lens 100, and adapter 300 adjust the back focus.

[0167] Referring to the flowchart in Figure 11, the process for correcting the lens display information when the camera 200, lens 100, and adapter 300 adjust the back focus will be explained.

[0168] Since steps S300 to S307 are the same as in Figure 9, we will omit the explanation.

[0169] Next, in step S501, the adapter microcontroller 302 checks whether the back focus adjustment of the adapter 300 has been performed. If the back focus adjustment has been performed, the process proceeds to step S502; otherwise, the process proceeds to step S503.

[0170] Next, in step S502, the adapter microcontroller 302 transmits the back focus adjustment amount to the camera microcontroller 206.

[0171] Next, in step S503, the lens microcontroller 111 checks whether the back focus of the lens 100 has been adjusted. If the back focus has been adjusted, the process proceeds to step S504; otherwise, the process proceeds to step S505.

[0172] Next, in step S504, the lens microcontroller 111 transmits the back focus adjustment amount to the camera microcontroller 206.

[0173] Next, in step S505, the camera microcontroller 206 checks whether the back focus of the camera 200 has been adjusted. If the back focus has been adjusted, the process proceeds to step S506; otherwise, the process proceeds to step S306.

[0174] Next, in step S506, the camera microcontroller 206 acquires the amount of back focus adjustment.

[0175] Next, in step S306, the camera microcontroller 206 corrects the lens display information received in step S305 based on the information on the amount of change in back focus received in steps S502, S505, and S506.

[0176] In this way, the lens display information is continuously corrected by repeatedly acquiring the amount of change in back focus of the camera 200, lens 100, and adapter 300.

[0177] In this way, the display on the display unit 204 can be corrected each time the camera 200, lens 100, and adapter 300 adjust the back focus, making it possible to provide the user with accurate information.

[0178] In the flowchart of Figure 9, the camera 200, lens 100, and adapter 300 can all perform back focus adjustment, but there are no particular limitations on the number or types of models that can be adjusted. There are also no particular limitations on the method of back focus adjustment. Furthermore, if multiple adapters capable of back focus adjustment are attached, the amount of back focus change may be transmitted to the camera for each adapter. Alternatively, the amount of flange back change may be transmitted instead of back focus change.

[0179] Figure 12 also shows an example where the camera microcontroller 206 displays the change in back focus on the display unit 204. In this way, the camera microcontroller 206 may also display the change in back focus or the adjustment amount of back focus acquired for the camera 200, lens 100, and adapter 300. In the example in Figure 12, the change in back focus is displayed individually, but the change in back focus of all components may be added together and displayed. Alternatively, the change in flange back may be displayed instead of back focus. [Example 3]

[0180] Next, Example 3 of the second embodiment will be described.

[0181] Example 3 describes a method in which the adapter microcontroller 302 receives lens display information from the lens microcontroller 111, corrects the lens display information, and then transmits it to the camera microcontroller 206.

[0182] The following describes the process by which the adapter microcontroller 302 receives lens display information from the lens microcontroller 111, corrects the lens display information, and then transmits it to the camera microcontroller 206, referring to the flowchart in Figure 13.

[0183] Since steps S301 to S305 are the same as in Figure 9, their explanation will be omitted.

[0184] Next, in step S701, the adapter microcontroller 302 relays the lens display information transmitted by the lens microcontroller 111 to the camera microcontroller 206.

[0185] Next, in step S702, the adapter microcontroller 302 corrects the lens display information based on the change in the back focus of the adapter 300.

[0186] Next, in step S703, the adapter microcontroller 302 transmits lens display information to the camera microcontroller 206.

[0187] Since S307 is the same as in Figure 9, its explanation is omitted.

[0188] In this way, even if the camera microcontroller 206 does not support correction of lens display information, the adapter microcontroller 302 can correct the lens display information, thus displaying the correct lens information to the user.

[0189] In this embodiment, the adapter 300 corrected the lens display information based on the change in the back focus of the adapter 300, but the lens display information may also be corrected based on the ID information or the change in back focus of the lens 100. Furthermore, if multiple adapters are attached, the adapter 300 may correct the lens display information by summing the changes in back focus of all attached accessories.

[0190] In this embodiment, the lens display information was corrected based on the change in back focus, but the lens display information may also be corrected based on the change in flange back.

[0191] <Third Embodiment> [Example 1]

[0192] Figure 14 shows the configuration of the interchangeable lens camera in this embodiment.

[0193] An interchangeable-lens camera consists of a lens unit 100 and a camera body 200. The lens unit 100 and the camera body 200 are mechanically and electrically connected via a mount (not shown), and power supply and mutual communication between the lens and camera are performed via terminals provided on the mount.

[0194] The lens device 100 has an optical system 101 that forms an optical image of the subject on the image sensor 201 of the camera body 200. The optical system 101 consists of a variable magnification lens 102, an aperture 103, and a focus lens 104. The lens device 100 represents a zoom lens with a variable focal length. The variable magnification lens 102 can be driven in the optical axis direction by operating the zoom operation unit 105, thereby changing the focal length of the lens device 100. The zoom position detection unit 108 is a position sensor for detecting the position of the variable magnification lens 102. The zoom position detection unit 108 is a vernier type absolute encoder. These zoom position detection units detect the position of the variable magnification lens 102 and output a detection signal to the lens control unit 106. Details of the method for calculating the absolute position using these sensor signals will be described later. The aperture 103 consists of aperture blades (not shown), and the aperture drive unit 109 moves the blades via an actuator to adjust the amount of light.

[0195] The focus lens 104 is moved in the optical axis direction via an actuator by the focus drive unit 110 to adjust the focus state. The focus position detection unit 111 detects the position of the focus lens 104 and transmits its position to the lens control unit 106. The lens control unit 106 is a computer with a CPU (Central Processing Unit). The lens control unit 106 transmits drive command values ​​to the aperture drive unit 109 and the focus drive unit 110, respectively, and controls the driving of the aperture 103 and the focus lens 104. The memory 112 is a storage means composed of ROM (Read Only Memory) or RAM (Random Access Memory), etc. Typical information stored in the memory 112 includes design information and adjustment value information necessary for calculating the absolute position of the variable magnification lens 102. It also stores optical information and individual adjustment values ​​necessary for driving the aperture 103 and the focus lens 104. The zoom operation unit 105 represents a mechanism that moves the zoom lens manually, such as a zoom ring, or a mechanism that moves it electrically using an actuator.

[0196] The camera body 200 consists of an image sensor 201, a signal processing unit 202, a recording processing unit 203, a defocus detection unit 206, a camera control unit 207, a memory 208, an electronic viewfinder 204, and a display unit 205. The image sensor 201 receives light from the optical system 101, generates an electrical signal by photoelectric conversion, and transmits it to the signal processing unit 202. In addition to pixels for imaging, the image sensor 201 also has pixels for detecting the focus position (not shown). The signal processing unit 202 converts the electrical signal from the image sensor 201 into a digital signal. Furthermore, the signal processing unit 202 performs various image processing on the digital signal, such as noise reduction and color correction, and transmits the image data to the recording processing unit 203.

[0197] 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 amount of defocus is determined by the detected phase difference and the amount of defocus is output to the camera control unit 207. The camera control unit 207 is an arithmetic unit 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 camera body 200 in response to inputs from the camera operation unit, such as a shooting switch and various setting switches (not shown).

[0198] Figure 15 shows the internal structure of the zoom position detection unit 108.

[0199] Figure 15(a) is a cross-sectional view of the zoom position detection unit 108. The movable part 1081 is a movable part that moves in the Z-axis direction perpendicular to the plane of the paper. The Z-axis direction corresponds to the optical axis direction in Figure 14. The fixed part 1082 is a reference part for the movement of the movable part 1081 and serves as the reference for the absolute position of the movable part 1081. The light source 1083 is a light-emitting part, for example, an LED. The scale part 1084 has three track patterns 1085a, 1085b, and 1086c arranged at different pitches along the entire length of the stroke. The light-receiving parts 1086a, 1086b, and 1087c are light-receiving parts for receiving light from the light source 1083 reflected by the track patterns 1085a, 1085b, and 1086c, respectively, and are composed of, for example, a photodiode array. The signal processing circuit 1807 processes the signals received by the light receiving units 1086a, 1086b, and 1087c and outputs a signal to the lens control unit 106. Figure 15(b) shows the scale unit 1084 as viewed in the XZ plane. The track patterns 1085a, 1085b, and 1086c are arranged in the Z direction, which is the direction of movement, at equal intervals of P1, P2, and P3, respectively. In this embodiment, the movable unit 1081 is equipped with the scale unit 1084, and the fixed unit 1082 is equipped with the light source 1083 and light receiving units 1086a, 1086b, and 1087c. However, the configuration is not limited to this, and a configuration in which the fixed unit 1082 is equipped with the scale unit 1084 is also acceptable.

[0200] Next, Figure 16 will explain the configuration related to the detection of the position of the variable magnification lens 102 and the determination of the drive range of the focus lens 104.

[0201] Figure 16 shows the components consisting of a zoom position detection unit 108, an A / D conversion unit 301, and a control device 300. The control device 300 is part of the lens control unit 106.

[0202] The zoom position detection unit 108 is a vernier-type absolute encoder that detects the position of the variable magnification lens 102, as shown in Figure 15.

[0203] The A / D conversion unit 301 converts the analog signal output from the zoom position detection unit 108 into a digital signal.

[0204] The synchronization margin calculation unit 303 calculates a synchronization margin to determine the reliability of the calculation result of the absolute position calculation unit 302.

[0205] The absolute position calculation unit 302 calculates the absolute position of the variable magnification lens 102 from the converted digital signal. The absolute position calculation unit 302 has a synchronization margin calculation unit 303 that calculates a value for determining the reliability of the output signal from the zoom position detection unit 108 when calculating the absolute position. For example, if the synchronization margin for the position calculated by the absolute position calculation unit 302 is less than a certain threshold, it is determined that the reliability is high and the position of the variable magnification lens 102 is confirmed. On the other hand, if the synchronization margin is above a certain threshold, it is determined that the reliability of the position of the variable magnification lens 102 is low and the zoom range is determined. Details will be described later. The determined zoom value is notified to the focus drive range determination unit 305.

[0206] The cam information 304 stores in memory 112 information about the drive range of the focus lens 104 according to the zoom position of the variable magnification lens 102. The drive range is the range in which the focus can be adjusted for a subject by the lens device 100. There is an appropriate drive range for the focus lens 104 depending on the zoom position. The cam information 304 will be explained using Figure 23. The horizontal axis represents the focus position. The vertical axis represents the zoom position, ranging from wide-angle to telephoto. The closest focus position 1006 indicates the focus position where the distance to the subject that can be focused for each zoom position is closest. The infinity focus position 1005 indicates the focus position where the distance to the subject that can be focused for each zoom position is furthest. The appropriate drive range for the focus lens 104 is the range that includes the closest focus position 1006 and the infinity focus position 1005.

[0207] The focus drive range determination unit 305 refers to the cam information 304 and the value determined by the absolute position calculation unit 302 to determine the drive range of the focus lens 104 and notifies the focus control unit 306. Further details will be described later.

[0208] The focus control unit 306 controls shooting operations such as focusing the focus lens 104 within the drive range determined by the focus drive range determination unit 305.

[0209] This section will explain how, when the absolute position of the variable magnification lens 102 is calculated at startup and the synchronization margin is above a predetermined threshold, and the reliability of the calculation result for the variable magnification lens 102 is low, the zoom position range of the variable magnification lens 102 is determined, and the provisional drive range of the focus lens 104 is determined accordingly.

[0210] First, we will explain how to calculate the zoom position of the variable magnification lens 102. This will be explained using Figures 17 to 21.

[0211] Figure 17 shows the output signal of the zoom position detection unit 108. The zoom position detection unit 108 outputs a periodic signal that matches the interval of the track patterns 1085a, 1085b, and 1086c. The photodiode array of the light receiving units 1086a, 1086b, and 1087c has an array structure that outputs two signals, and two sinusoidal signals with a phase difference are output. These signals are taken into the lens control unit 106 via the A / D conversion unit 301, where the absolute position is calculated.

[0212] Figure 18 shows the flow of absolute position calculation by the absolute position calculation unit 302 and the synchronization margin calculation unit 303. Figure 18 will now be explained.

[0213] In step S501, the acquired sensor signal is corrected. After offset adjustment and amplitude adjustment, an arctangent calculation is performed to obtain a periodic sawtooth wave signal. Details of these calculation methods are disclosed in prior art and are therefore omitted here. Figure 19 is an image diagram of the output waveform after signal processing in step S501. The sensor signal from the zoom position detection unit 108 is represented as Atan signals 1 to 3. In this embodiment, they are represented as sawtooth waves with 161, 80, and 37 peaks, respectively, depending on the number of scale patterns. Since the output is obtained by arctangent calculation, it is assumed to take values ​​from 0 to 360°.

[0214] In step S502, vernier signals are generated from the zoom position detection unit 108 signals, which underwent signal processing in step S501, in order to calculate the absolute position. In the case of a vernier absolute encoder in this embodiment, three types of vernier signals are generated. The first vernier signal is generated by subtracting twice the number of Atan signal 2 from Atan signal 1. The second vernier signal is generated by subtracting twice the number of Atan signal 3 from Atan signal 2. The third vernier signal is generated by subtracting four times the number of Atan signal 3 from Atan signal 1. However, since each vernier signal is generated from the Atan signal and is treated as angle information, angle conversion is performed so that the number falls within the range of 0 to 360°. Figure 20 shows the calculation results of the various signals after signal processing 2 in step S502. The vernier signal becomes a signal with one peak for the detectable range of the zoom position detection unit B108. Similarly, vernier signals 2 and 3 become signals with 6 and 13 peaks, respectively.

[0215] In step S503, the absolute position is calculated using these three vernier signals, Atan signal 3, and Atan signal 1. The absolute position is calculated by performing a synchronization process on the five signals shown in Figure 20. Figure 21 shows an overview of the synchronization process. Figure 21(a) shows the synchronization process for vernier signal 1 and vernier signal 2. Vernier signal 1 is a signal with one peak across the entire detection range, and vernier signal 2 is a signal with six peaks. Vernier signal 1 is multiplied by 6, which is the ratio of the number of peaks. Here, for the sake of simplicity, assuming that the smallest unit of angle within the CPU is 1°, the signal obtained by multiplying vernier signal 1 by 6 will be a signal that changes from 0 to 2160° in increments of 6. By subtracting vernier signal 2 from this, step signal 1 can be obtained. Dividing this step signal by 360° gives the number of peaks of vernier signal 2. By multiplying this number of peaks by 360° and adding vernier signal 2, synchronization signal 1 can be obtained. On the graph, the signal obtained by multiplying Vernier signal 1 by 6 appears superimposed, but synchronization signal 1 is obtained by adding Vernier signal 2 to the number of peaks, so it changes from 0 to 1 increments, resulting in a signal of 2160°. Vernier signal 1 was a signal that divided the position detection range into 360 parts, but by performing synchronization processing with Vernier signal 2, the position detection range can be divided into 2160 parts, allowing for management of position information with a finer number of divisions.

[0216] Figure 21(b) shows the synchronization process of synchronization signal 1 and vernier signal 3. Similar to (a), the ratio of the number of peaks is 13:6, so by multiplying synchronization signal 1 by 13 / 6 and subtracting vernier signal 3, we can obtain step signal 2. Performing the calculation as in (a) yields synchronization signal 2. Synchronization signal 2 is a signal that changes from 0 to 4680° in increments of 1, consisting of 360° × 13 peaks. Similarly, by proceeding with the synchronization process in (c) and (d), we can ultimately obtain an absolute position signal that divides the position detection range into 57960 segments. In addition, the synchronization margin calculation unit 303 calculates the synchronization margin during the synchronization calculation. These synchronization calculations are described in Patent Document 2 and are therefore omitted here. The synchronization margin is calculated for each of the following relationships: vernier signal 1 and vernier signal 2, vernier signal 2 and vernier signal 3, vernier signal 3 and Atan signal 3, and Atan signal 3 and Atan signal 1.

[0217] In step S504, the calculated absolute position is converted. In this embodiment, assuming that position detection is to be performed with the finest possible detection resolution, the absolute position is divided into 57,960 parts.

[0218] Furthermore, the absolute position calculation unit 302 also determines whether the synchronization calculation is normal or not. By referring to each synchronization margin calculated by the synchronization margin calculation unit 303, if all values ​​are below the threshold, it is determined that the reliability is high; if any signal is above the threshold, it is determined that the reliability is low.

[0219] If the reliability of the synchronous calculation results is deemed high, the zoom position of the variable magnification lens 102 is determined, and the process is terminated.

[0220] On the other hand, the zoom range is determined by referring to the synchronization margin value as a result of the synchronization calculation and determining that the reliability is low. If the value of each calculated synchronization margin exceeds a certain threshold, the reliability of the calculated result is determined to be low. The detection error between signals where the synchronization margin relationship is above the threshold is used as the zoom range.

[0221] The detection error is calculated in the absolute position calculation unit 302. Between signals with low synchronization margin reliability, for example, in Figure 20, the signal with more peaks between signals may be misread by reading the signal with the peak next to the signal that should be there. Therefore, the detection error is calculated from the ratio of peaks between signals with low reliability.

[0222] Furthermore, it is possible to store a fixed value for the detection error between each of the above signals. For signals whose synchronization margin is greater than or equal to a threshold, the zoom position range may be set by referring to the fixed value stored in memory 112.

[0223] The zoom range will be explained using Figure 23. The dotted line 1002 shows the result of the absolute position calculated in step S503. The dotted line 1003 shows the wide-angle side of the focal length of the zoom position considering detection error. The dotted line 1004 shows the telephoto side of the focal length of the zoom position considering detection error. The range of the zoom position is as indicated by arrow 1001.

[0224] As described above, the zoom range is determined and the process is terminated.

[0225] Figure 22 will be used to explain the control process when a lens-interchangeable camera is started up.

[0226] Step S901 activates the zoom position detection unit 108, which is a means for detecting the position of the variable magnification lens 102. The absolute position calculation unit 302 and the synchronization margin calculation unit 303 perform calculations for the absolute position and synchronization margin, and calculate information for determining the reliability of the zoom position and its detection result.

[0227] In step S902, the absolute position calculation unit 302 refers to the result of the synchronization margin calculation performed by the synchronization margin calculation unit 303.

[0228] Step S903 determines whether the calculated zoom position is reliable information by checking whether the calculation result of the synchronization margin between each signal in the absolute position calculation unit 302 is above a certain threshold. If all of the calculated synchronization margins are below the threshold, it is determined to be highly reliable. If any of the calculated synchronization margins are above the threshold, it is determined to be unreliable.

[0229] Step S904 occurs when the absolute position calculation unit 302 determines that the calculation result of the zoom position detection unit 108 is highly reliable, and it confirms the absolute position calculation result as the position of the variable magnification lens 102.

[0230] In step S905, the drive range of the focus lens 104 corresponding to the zoom position is determined from the zoom position of the variable magnification lens 102 and the cam information 304, and this is set as the drive range in the focus control unit 306.

[0231] Step S906 occurs when the absolute position calculation unit 302 determines that the reliability is low. As already mentioned, the zoom range is determined by adding the detection error to the position result calculated by the absolute position calculation unit 302.

[0232] In step S907, the focus drive range determination unit 305 determines a provisional focus drive range from the cam information 304 and the zoom range determined in step S906, and sets it in the focus control unit 306.

[0233] The provisional drive range of the focus lens 104 will be explained using Figure 23. The cam information 304, which represents the relationship between the zoom position and the focus position, has already been described.

[0234] The position of the variable magnification lens 102 is highly reliable, and once the zoom position is determined, the appropriate drive range of the focus lens 104 is set accordingly.

[0235] This section describes how to determine the provisional drive range of the focus lens 104 when the reliability of the position of the variable magnification lens 102 is low and the zoom range has been determined. The setting of the zoom range of the variable magnification lens 102 has already been described.

[0236] The range of the focus lens 104's position, including the maximum and minimum focus positions within the aforementioned zoom range, is determined as the provisional drive range. Within the zoom range indicated by arrow 1001, the minimum focus position is the intersection of dotted line 1004 and the nearest focus position 1006. On the other hand, the maximum focus position is the intersection of dotted line 1003 and the infinity focus position 1005. The range of the focus lens's drive range indicated by arrow 1007 is determined as the provisional drive range of the focus lens 104.

[0237] The above explains the process shown in Figure 22.

[0238] Even when the reliability of the position of the variable magnification lens 102 is low, the zoom position range can be determined from the detection error, and the provisional drive range of the focus lens 104 can be determined according to that range, thereby suppressing the subject distance at which focusing becomes impossible without performing a recovery operation. This reduces situations where the user is unable to continue shooting or is unable to adjust focus on the subject.

[0239] Furthermore, it is possible to notify the user via the display unit 205 of the camera body 200 that the position of the variable magnification lens 102 is unreliable and the drive range of the focus lens 104 is different from normal.

[0240] By sending a user notification, it becomes possible to recognize that the reliability of the detection result of the variable magnification lens 102 is low and that the focus drive range is in a state where it is set to a provisional drive range. [Example 2]

[0241] In Example 1, when a lens-interchangeable camera is started up, the absolute position of the variable magnification lens 102 is unreliable, and an example is shown in which the zoom range is determined and the provisional drive range of the focus lens 104 is determined.

[0242] In this embodiment, we will explain the method for returning from a state where the provisional drive range of the focus lens 104 has been determined, to a state where the reliability of the absolute position of the variable magnification lens 102 is ensured by operating the zoom operation unit 105.

[0243] Figures 24 and 25 will be used to illustrate this point.

[0244] First, let's explain Figure 24.

[0245] Step S1101 detects whether the zoom control unit 105 is being operated by the user. The system determines whether the user is operating the unit based on the change in the absolute position calculated by the absolute position calculation unit 302. If there is a change, the system proceeds to step S1102. If there is no change, monitoring continues.

[0246] In step S1102, if the absolute position calculated by the absolute position calculation unit 302 is confirmed to have changed, the absolute position calculation unit 302 and the synchronization margin calculation unit 303 perform calculations for the absolute position and synchronization margin, and calculate information for determining the reliability of the zoom position and its detection result. The synchronization margin is calculated between signals in the same way as in Example 1.

[0247] Step S1103 refers to all synchronization margins calculated in step S1102, compares the calculated results against a certain threshold, and if all are below the threshold, it is determined that the calculation results are highly reliable, and the process proceeds to step S1104. If any of the calculation results show a synchronization margin greater than or equal to the threshold, it is determined that the reliability is low, and step S1102 is executed again.

[0248] In step S1104, the focus drive range determination unit 305 refers to the highly reliable zoom position of the variable magnification lens 102 and the cam information 304 determined by the absolute position calculation unit 302.

[0249] In step S1105, the focus drive range determination unit 305 determines the drive range of the focus lens 104 corresponding to the zoom position from the value referenced in step S1104, updates the drive range of the focus lens 104, and sets the drive range to the focus control unit 306.

[0250] Step S1106 controls the position of the focus lens 104, as shown in Figure 25, based on the drive range of the focus lens 104 updated in step S1105.

[0251] Let's explain using Figure 25.

[0252] Step S1201 compares the position of the focus lens 104 with the drive range of the focus lens 104 to determine whether the position of the focus lens 104 is within the drive range of the focus lens 104. If the position of the focus lens 104 is within the drive range of the focus lens 104, the process ends. If the position of the focus lens 104 is outside the drive range of the focus lens 104, the process proceeds to step S1202.

[0253] In step S1202, the focus control unit 306 issues a command to drive the focus lens 104 to move to the end of the drive range.

[0254] As described above, when the interchangeable lens camera is started up, the reliability of the position information of the variable magnification lens 102 is low, and the camera returns from operating in the temporary drive range state of the focus lens 104 to the normal drive range of the focus lens 104.

[0255] Furthermore, it is possible to notify the user via the display unit 205 of the camera body 200 or the like that the reliability of the position of the variable magnification lens 102 has been restored. [Example 3]

[0256] In Example 2, a method for returning to the original position by fixing the position of the variable magnification lens 102 through operation of the zoom operation unit 105 was described, starting from a state where the provisional drive range has been determined. However, even when no operation is performed by the zoom operation unit 105, a control method for reducing the zoom position range and thereby reducing the provisional drive range of the focus will be described by referring to the autofocus focus adjustment result.

[0257] We will explain using Figure 26.

[0258] Step S1301 involves referring to the autofocus result from the camera body 200. The camera control unit 207 adjusts the focus based on the amount of defocus detected by the defocus detection unit 206. After the camera control unit 207 adjusts the focus and reaches the in-focus position, the lens control unit 106 receives notification from the camera control unit 207 that the camera is in focus. The lens control unit 106 then notifies the focus control unit 306 of this information.

[0259] If the focus is achieved, proceed to step S1302. If the focus is not achieved, continue monitoring in step S1301.

[0260] In step S1302, the focus drive range determination unit 305 obtains the position of the focus lens 104 in focus from the focus control unit 306 and refers to the cam information 304. Within the set zoom range, the range that includes the position of the focus lens 104 in focus can be estimated as the zoom range estimated from the focus state.

[0261] In step S1303, if the focus drive range determination unit 305 was updated in step S1302, it updates the drive range of the focus lens 104 from the updated zoom range and cam information 304 and notifies the focus control unit 306.

[0262] As described above, by referring to the autofocus results from the camera body 200, the zoom range of the variable magnification lens 102 can be newly estimated from the cam information 304, and the provisional drive range of the focus lens 104 can be updated accordingly.

[0263] 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 essence. [Explanation of Symbols]

[0264] 100 Lens drive unit operating device 200a Reference Lens Device 200b Operated Lens Device 300 Control device 303 First optical information processing unit for calculating the optical information of the reference lens 304 Second optical information processing unit for calculating optical information of the lens being operated 305 Command value changing unit for changing drive command value

Claims

1. A shooting system comprising a plurality of lens devices having drive units for driving optical elements for changing optical properties, and an operating device for operating the drive unit of at least one of the plurality of lens devices, A command value calculation unit calculates a drive command value for the drive unit of the operated lens device operated by the operating device, based on the amount of operation of the operating device, A first optical information processing unit calculates a first variation in the optical characteristics when the drive command value is input to the operated lens device, The system includes a second optical information processing unit that calculates a second amount of variation in the optical characteristics when the drive command value is input to a reference lens device separate from the operated lens device, A control device for an imaging system, characterized by having a command value changing unit that changes the drive command value so that at least a portion of the first amount of variation and the second amount of variation are the same.

2. The control device according to claim 1, characterized in that the first optical information processing unit calculates at least one of the zoom magnification variation amount, focus object distance shift amount, light intensity variation amount, and depth of field variation amount based on at least one of the drive command value, reference lens device model information, zoom position, focus position, and aperture position.

3. The control device according to claim 1, characterized in that the second optical information processing unit calculates at least one of the zoom magnification variation amount, focus object distance shift amount, light intensity variation amount, and depth of field variation amount based on the drive command value, the model information of the operated lens device, zoom position, focus position, and aperture position.

4. The second optical information processing unit is: The control device according to claim 1, comprising at least one of a second magnification variation calculation unit for calculating a second zoom magnification variation when the drive command value is input to the reference lens device, a second object distance shift calculation unit for calculating a second focus object distance shift, a second light intensity variation calculation unit for calculating a second light intensity variation, or a second depth of field variation calculation unit for calculating a second depth of field variation.

5. The command value changing unit is, The control device according to claim 1, characterized in that when the operating device operates the zoom of the operated lens device, the amount of zoom magnification change of the operated lens device when the operating amount is less than or equal to a predetermined value becomes the same as the amount of zoom magnification change when the operating amount is input to the reference lens device, and when an operating amount that maximizes the zoom drive speed of the operated lens device is input, the drive command value is changed to drive the zoom at the maximum drive speed.

6. The command value changing unit is, The control device according to claim 1, characterized in that the drive command value is changed so that the amount of focus object distance movement with respect to the amount of operation when the operating device operates the focus of the operated lens device is the same as the amount of focus object distance movement when the amount of operation is input to the reference lens device.

7. The command value changing unit is, The control device according to claim 1, characterized in that the drive command value is changed so that the amount of change in light intensity or depth of field with respect to the amount of operation when the operating device operates the aperture of the operated lens device is the same as the amount of change in light intensity or depth of field when the amount of operation is input to the reference lens device.

8. The control device according to claim 1, characterized in that when the zoom, focus, and aperture drive units of the operated lens device drive outside the drive range of the reference lens device, the second optical information processing unit calculates the zoom magnification change amount, the focus object distance shift amount, the light intensity change amount, and the depth of field change amount as if the reference lens device were virtually driven in a drive range outside its drive range.

9. The aforementioned reference lens device is The control device according to claim 1, characterized in that it is one of the plurality of lens devices constituting the imaging system, or a lens device not configured in the imaging system, or a virtual lens device.

10. A lens device having a drive unit, wherein the drive unit is operated by an operating device that operates at least one of the drive units, which controls zoom, focus, and aperture, A command value calculation unit calculates a drive command value for the drive unit operated by the operating device based on the amount of operation of the operating device, A first optical information processing unit calculates a first variation in the optical characteristics when the drive command value is input to the lens device, The system includes a second optical information processing unit that calculates a second amount of variation in the optical characteristics when the drive command value is input to a reference lens device separate from the aforementioned lens device. A lens device characterized by having a command value changing unit that changes the drive command value so that at least a portion of the first amount of variation and the second amount of variation are the same.

11. In an operating device for operating at least one of the drive units of a lens device having a drive unit, such as zoom, focus, or aperture, A command value calculation unit calculates a drive command value for the drive unit operated by the operating device based on the amount of operation of the operating device, A first optical information processing unit calculates a first variation in the optical characteristics when the drive command value is input to the lens device, The system includes a second optical information processing unit that calculates a second amount of variation in the optical characteristics when the drive command value is input to a reference lens device separate from the aforementioned lens device. An operating device characterized by having a command value changing unit that changes the drive command value so that at least a portion of the first fluctuation amount and the second fluctuation amount are the same.

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