Lens device, imaging apparatus, method for controlling lens device, and program

Abstract

To provide a lens device that, in zooming, can reduce the difference in the quantity of light between two optical systems in a stereo zoom lens to prevent a change in the quantity of light.SOLUTION: A lens device (2) has: a first optical system (210) that has a first zoom lens (220) and a first aperture stop (230); a second optical system (310) that is arranged in parallel with the first optical system, and has a second zoom lens (320) and a second aperture stop (330); a position detection unit (400) that detects the position of the first zoom lens; and a control unit (500) that controls the aperture diameters of the first aperture stop and the second aperture stop. The control unit controls the aperture diameters of the first aperture stop and the second aperture stop on the basis of the position of the first zoom lens.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a lens apparatus, an imaging apparatus, a control method for a lens apparatus, and a program. [Background technology]

[0002] In recent years, with the spread of head-mounted displays and other devices, two-lens stereo lenses capable of 3D imaging have been attracting attention. In addition, the diversification of imaging possibilities has led to a demand for stereo lenses with zoom mechanisms. However, in stereo lenses with zoom mechanisms, when the focal length changes due to the movement of the zoom lens group, the aperture value changes even if the aperture diameter remains unchanged. Therefore, when the focal length changes, the aperture diameter must be corrected to match the focal length in order to maintain the same aperture value. In stereo zoom lenses, the aperture diameters of the left and right apertures must be changed during zooming, but the difference in static light intensity between the left and right lenses and the difference in dynamic light intensity change can lead to a sense of discomfort for the user. Therefore, it is necessary to correct the aperture diameter to avoid any discomfort for the user.

[0003] Patent Document 1 discloses a method for correcting the aperture diameter of an aperture in a twin-lens lens device. Patent Document 2 discloses a method for correcting the aperture diameter of an aperture in a single-lens lens device during zooming. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-91150 [Patent Document 2] Japanese Patent Application Publication No. 2019-207334 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 does not disclose a method for correcting the aperture diameter of the diaphragm when zooming in a twin-lens lens device. Patent Document 2 does not disclose an optimal correction method when applied to a twin-lens lens device. For this reason, the methods disclosed in Patent Documents 1 and 2 are unable to reduce the difference in light intensity between the two optical systems and suppress unnecessary changes in light intensity when zooming in a twin-lens lens device (stereo zoom lens).

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a lens device that can reduce the difference in light amount between two optical systems in a stereo zoom lens during zooming, thereby suppressing changes in the amount of light. [Means for solving the problem]

[0007] A lens device according to one aspect of the present invention includes a first optical system having a first zoom lens and a first aperture stop, a second optical system having a second zoom lens and a second aperture stop arranged in parallel with the first optical system, a position detection unit that detects the position of the first zoom lens, and a control unit that controls the aperture diameters of the first aperture stop and the second aperture stop, wherein the control unit controls the aperture diameters of the first aperture stop and the second aperture stop based on the position of the first zoom lens.

[0008] Other objects and features of the present invention will be described in the following embodiments. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a lens device that can reduce the difference in light amount between two optical systems in a stereo zoom lens and suppress changes in light amount during zooming. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram of an imaging apparatus according to an embodiment of the present invention. [Figure 2] 5 is a diagram showing the relationship between a control amount (corrected target control amount) and brightness (target brightness) in the present embodiment. FIG. [Figure 3] 6 is a diagram showing the relationship between a correction target control amount and a target brightness in the present embodiment. FIG. [Figure 4] FIG. 4 is a diagram showing the relationship between the zoom position of the first zoom lens group and the correction target control amount of the first aperture in this embodiment. [Figure 5] 10 is a diagram showing the relationship between the zoom position of the second zoom lens group and the correction target control amount of the second aperture in this embodiment. FIG. [Figure 6] 5A and 5B are diagrams showing the relationship between target brightness and aperture diameter at each zoom position in this embodiment. [Figure 7] 10A and 10B are diagrams showing the relationship between the target brightness and the aperture diameter when the start position is changed in this embodiment. [Figure 8] 10A and 10B are diagrams illustrating the relationship between the target brightness and the aperture diameter when the start position is different in this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0012] First, the basic configuration of an imaging device 1 in this embodiment will be described with reference to Fig. 1. Fig. 1 is a block diagram of the imaging device 1. The imaging device 1 has a camera body 110 and an interchangeable lens (lens device) 2. The interchangeable lens 2 is detachably attached to the camera body 110. The imaging device 1 is an interchangeable lens camera system in which the camera body 110 and the interchangeable lens 2 are detachable. However, this embodiment is not limited to this, and can also be applied to an imaging device in which the camera body and the lens device are configured as an integrated unit.

[0013] First, the configuration of the interchangeable lens 2 will be described. The interchangeable lens 2 has a first optical system 210, a second optical system 310, a first aperture drive unit 240, a second aperture drive unit 340, a position detection unit 400, a lens microcomputer (control unit) 500, and a storage unit 600. The first optical system 210 and the second optical system 310 are arranged parallel to each other and are optical systems of the same configuration with a predetermined focal length. In this embodiment, the first optical system 210 is a right-eye optical system and the second optical system 310 is a left-eye optical system, but these may be reversed.

[0014] The first optical system 210 has a first zoom lens group (first zoom lens) 220 and a first diaphragm (first aperture diaphragm) 230. The second optical system 310 has a second zoom lens group (second zoom lens) 320 and a second diaphragm (second aperture diaphragm) 330. The first zoom lens group 220 and the second zoom lens group 320 are moved in a direction along the optical axis OA (optical axis direction) by a user operating an operation unit (not shown), thereby changing the focal length of each optical system. The drive mechanisms of the first zoom lens group 220 and the second zoom lens group 320 may be mechanically coupled to the operation unit, or may each be provided with a motor and driven by an electrical signal from the operation unit. The first zoom lens group 220 and the second zoom lens group 320 may be mechanically coupled to each other, or may be configured to be independently drivable.

[0015] Generally, in a stereo zoom lens, it is desirable that the left and right zoom positions (zoom positions of the first optical system 210 and the second optical system 310) be equal to each other. This is because if the left and right zoom positions are different, the angles of view of the left and right images will be different, preventing a good 3D experience. For this reason, in this embodiment, the positions of the first zoom lens group 220 and the second zoom lens group 320 are mechanically or electrically controlled so that the zoom magnifications are equal to each other even if the drive mechanisms of the first zoom lens group 220 and the second zoom lens group 320 are independent of each other.

[0016] The first diaphragm 230 and the second diaphragm 330 each have, for example, a plurality of diaphragm blades (not shown) and an opening / closing mechanism (not shown) that opens and closes the plurality of diaphragm blades, and are diaphragms that adjust the amount of light in the first optical system 210 and the second optical system 310. Specifically, the first diaphragm 230 and the second diaphragm 330 are each so-called iris diaphragms (aperture diaphragms) in which a plurality of diaphragm blades arranged around the optical axis OA partially overlap each other to form an aperture on the optical axis OA.

[0017] The first aperture drive unit 240 is a drive means that drives an opening / closing mechanism provided in the first aperture 230. Similarly, the second aperture drive unit 340 is a drive means that drives an opening / closing mechanism provided in the second aperture 330. The aperture values ​​(F-numbers) of the first aperture 230 and the second aperture 330 vary depending on the positions of the multiple aperture blades. In the first aperture 230 and the second aperture 330, the amount of overlap between the multiple aperture blades varies depending on the positions of the multiple aperture blades. Therefore, the operating loads applied to the first aperture drive unit 240 and the second aperture drive unit 340 vary depending on the positions of the multiple aperture blades in the first aperture 230 and the second aperture 330.

[0018] Generally, as the aperture value of each of the first aperture 230 and the second aperture 330, i.e., the amount of overlap between the aperture blades, increases, the operating load applied to the first aperture drive unit 240 and the second aperture drive unit 340 increases. The first aperture drive unit 240 and the second aperture drive unit 340 are configured to include, for example, stepping motors.

[0019] The lens microcomputer 500 controls (changes) the aperture diameters of the first aperture 230 and the second aperture 330. That is, the lens microcomputer 500 controls the first aperture driver 240 and the second aperture driver 340 to drive the first aperture 230 and the second aperture 330, respectively. For example, the lens microcomputer 500 controls the drive directions of the first aperture driver 240 and the second aperture driver 340 by changing the polarity of the drive signals applied to the first aperture driver 240 and the second aperture driver 340. The lens microcomputer 500 also controls the drive positions of the first aperture driver 240 and the second aperture driver 340 by changing the number of pulses of the drive signals applied to the first aperture driver 240 and the second aperture driver 340. This allows the first aperture 230 and the second aperture 330 to change the opening and closing operation amounts (opening amount, opening diameter) of the multiple aperture blades.

[0020] Furthermore, the first aperture drive unit 240 and the second aperture drive unit 340 are each provided with an aperture position detection unit (not shown) that detects the positions of multiple aperture blades corresponding to the maximum aperture position (maximum F-number). In the interchangeable lens 2 of this embodiment, the aperture position detection unit is provided in consideration of cases where an impact has been received, but open control may be performed on the aperture position detection unit by counting pulses of a stepping motor.

[0021] Furthermore, the lens microcomputer 500 controls the aperture size (aperture diameter) of each of the first aperture 230 and the second aperture 330 via the camera microcomputer 140. The aperture diameters of each of the first aperture 230 and the second aperture 330 are controlled based on a signal (target aperture value signal) received from the camera body 110 and the position of the first zoom lens group 220 detected by the position detection unit 400. Furthermore, when controlling the first aperture drive unit 240 and the second aperture drive unit 340, the lens microcomputer 500 obtains a target control amount from a table stored in the storage unit 600.

[0022] The storage unit 600 stores a first drive instruction table (first data) 250, a second drive instruction table (second data) 350, and a first drive range table (third data) 260. The first drive instruction table 250 is a data table showing the relationship between the target brightness (first target light intensity) of the first optical system 210 and the target control amount (corrected target control amount, first drive instruction value) of the first aperture 230 when the first zoom lens group 220 is located at a predetermined position. Similarly, the second drive instruction table 350 is a data table showing the relationship between the target brightness (second target light intensity) of the second optical system 310 and the target control amount (corrected target control amount, second drive instruction value) of the second aperture 330 when the second zoom lens group 320 is located at a predetermined position. Note that in this embodiment, the predetermined position is, for example, the telephoto end position (TELE state), but is not limited to this and may be another position such as the wide-angle end position (WIDE state).

[0023] The first drive instruction table 250 is data created based on the light intensity (actual measurement value) of the first optical system 210 measured while changing the aperture diameter of the first aperture 230. Similarly, the second drive instruction table 350 is data created based on the light intensity (actual measurement value) of the second optical system 310 measured while changing the aperture diameter of the second aperture 330.

[0024] The first drive range table 260 is a data table that indicates the drive ranges of the first drive instruction table 250 and the second drive instruction table 350 for each position (zoom position) of the first zoom lens group 220. In other words, the first drive range table 260 indicates the relationship between the position of the first zoom lens group 220 and the shift amount from the first drive instruction value (start position 262). In this way, the first drive range table 260 is data that is created without using data related to the second zoom lens group 320.

[0025] The lens microcomputer 500 selects at least a portion of data from the data stored in the first drive instruction table 250 and the second drive instruction table 350, based on the position of the first zoom lens group 220 detected by the position detection unit 400. The lens microcomputer 500 then controls the aperture size of each of the first diaphragm 230 and the second diaphragm 330, using the data selected based on the position of the first zoom lens group 220. That is, instead of using data that changes depending on the position of the second zoom lens group 320, the lens microcomputer 500 controls the aperture size of each of the first diaphragm 230 and the second diaphragm 330 using data that changes depending on the position of the first zoom lens group 220 (third data).

[0026] In this way, the lens microcomputer 500 changes the aperture diameter of the first aperture 230 using the first drive instruction table 250 and the first drive range table 260, and changes the aperture diameter of the second aperture 330 using the second drive instruction table 350 and the first drive range table 260. More specifically, the lens microcomputer 500 shifts each of the first drive instruction value and the second drive instruction value by a shift amount (start position 262) according to the position of the first zoom lens group 220.

[0027] In this embodiment, the interchangeable lens 2 has a storage unit 600 that stores various data (first drive instruction table 250, second drive instruction table 350, first drive range table 260), but is not limited to these. At least a portion of the data stored in the storage unit 600 may be stored in a device separate from the interchangeable lens 2, such as a cloud computing system. In this case, the lens microcomputer 500 can receive the necessary data via wireless communication or the like and control the opening size of each of the first aperture 230 and the second aperture 330.

[0028] Next, the configuration of camera body 110 will be described. As shown in Fig. 1, camera body 110 includes an image sensor 120, a signal processing circuit 130, and a camera microcomputer 140. Image sensor 120 is a photoelectric conversion element such as a CMOS (Complementary Metal-Oxide-Semiconductor) sensor or a CCD (Charge Coupled Device) sensor. Image sensor 120 receives an optical image (subject image) formed via first optical system 210 and second optical system 310 and performs photoelectric conversion to acquire image data. Image sensor 120 then outputs the acquired image data to camera microcomputer 140 via signal processing circuit 130.

[0029] In this embodiment, camera body 110 has a single image sensor 120, with half of image sensor 120 receiving an optical image by first optical system 210 and the other half receiving an optical image by second optical system 310, but this is not limited to this. In other words, two image sensors corresponding to first optical system 210 and second optical system 310 may be disposed within camera body 110. Camera microcomputer 140 controls image sensor 120 and transmits target brightness to lens microcomputer 500.

[0030] Next, the first drive instruction table 250 and the second drive instruction table 350 in this embodiment will be described with reference to Fig. 2(a). Fig. 2(a) shows the relationship between the control amount for the first aperture 230 and the second aperture 330 and the brightness at the corresponding actual aperture positions when the first zoom lens group 220 and the second zoom lens group 320 are each at the telephoto end position (TELE state). In Fig. 2(a), the change in brightness at the actual aperture position of the first aperture 230 is shown by a solid line, and the change in brightness at the actual aperture position of the second aperture 330 is shown by a dashed line.

[0031] The horizontal axis in FIG. 2(a) corresponds to the control amount (aperture control amount, aperture diameter). As the control amount decreases, the aperture diameter of each of the first aperture 230 and the second aperture 330 increases. The vertical axis in FIG. 2(a) corresponds to brightness (aperture value, light intensity). As the brightness approaches AV0, the brightness at the actual aperture positions of the first aperture 230 and the second aperture 330 increases. In other words, by setting the control amount for each of the first aperture 230 and the second aperture 330 to 0, the brightness AV0 when the first aperture 230 and the second aperture 330 are both fully apertured is set. In other words, the brightness AV0 is the light intensity at the fully apertured diameter of each optical system. The brightness AV0 may be determined by a predetermined fixed aperture in the optical system, or may be determined by a jig or the like that can set a predetermined brightness using a predetermined aperture diameter.

[0032] It should be noted that AV0, AV1, AV2, and so on shown on the vertical axis in Figure 2(a) do not indicate actual AV values, but rather target brightnesses corresponding to target control amounts 0, 1, 2, and so on. Specifically, AV1, AV2, AV3, AV4, and AV5 are set so that the brightness is darker by a predetermined number of steps than the brightness AV0 at full aperture. In the interchangeable lens 2 according to this embodiment, the target control amounts 0 to 5 and target brightnesses AV0 to AV5 shown in Figure 2(a) are merely examples, and the respective numbers of target control amounts and target brightnesses are not limited to these.

[0033] Each of the first diaphragm 230 and the second diaphragm 330 has mechanical play, such as play at the connection with the first diaphragm drive unit 240 and the second diaphragm drive unit 340, and play in the cam mechanism that opens and closes the multiple diaphragm blades. Furthermore, each of the first diaphragm 230 and the second diaphragm 330 has manufacturing variations in its components. For this reason, even if the first diaphragm 230 and the second diaphragm 330 are controlled with the same control amount, the first diaphragm 230 and the second diaphragm 330 will be driven to positions with different opening diameters.

[0034] As described above, individual differences occur in the positions at which the aperture diameters of the first and second apertures 230 and 330 are driven, resulting in differences in brightness at the actual aperture positions. In the example shown in FIG. 2A, even when the first and second apertures 230 and 330 are controlled using target control amount 5, the brightness at the corresponding actual aperture positions between the first and second apertures 230 and 330 differs by A. This results in a difference in brightness between the two optical images formed via the first and second optical systems 210 and 310, respectively, at the image sensor 120, and thus between the two acquired image data. Therefore, in this embodiment, the control amounts of the first and second apertures 230 and 330 are corrected so that the brightness at the actual aperture positions corresponding to the first and second apertures 230 and 330 for each control amount is equal to each other.

[0035] Next, a specific method for correcting the control amount will be described in detail with reference to Figures 2(b) and (c). Figures 2(b) and (c) are diagrams showing how the control amounts of the first aperture 230 and the second aperture 330 are corrected. Note that the correction process described below may be performed by attaching the interchangeable lens 2 according to this embodiment to an external device, or may be performed in the camera body 110 to which the interchangeable lens 2 according to this embodiment is attached.

[0036] First, as shown in Fig. 2(b), target control amounts 0 to 5 (target aperture diameters) are set for the first aperture 230 so that target brightnesses AV0(1) to AV5(1) are set via the first aperture 230 in the first optical system 210. At this time, because the first aperture 230 has the aforementioned backlash and manufacturing variations, when a predetermined target control amount is set, the brightness at the actual aperture position deviates from the corresponding target brightness, as shown by the black circles in Fig. 2(b).

[0037] Therefore, in this embodiment, it is assumed that the brightness changes linearly with the change in the control amount between two adjacent target brightnesses among the target brightnesses AV0(1) to AV5(1) (target light amounts). Then, the target control amount corresponding to each of the target brightnesses AV0(1) to AV5(1) is determined. In this way, corrected target control amounts (corrected target control amounts) 0 to 5a corresponding to each of the target brightnesses AV0(1) and AV1(1) to AV5(1) are determined, as shown by the white circles in FIG. 2(b).

[0038] The first drive instruction table 250 is also used at other zoom positions according to the first drive range table 260, which will be described later. Therefore, the first drive instruction table 250 requires target brightnesses of AV0(1) to AV5(1) plus a zoom correction amount and corresponding target control amounts. Here, the zoom correction amount depends on the amount of change in aperture diameter due to zooming of the first optical system 210.

[0039] Next, the same correction process as described above is performed on the second aperture 330, but the target brightness of the second optical system 310 is set based on the target brightness of the first optical system 210. Specifically, as shown in FIG. 2(c), first, the difference is calculated between the target brightness AV0(2) (first light intensity) at a target control amount 0 (predetermined aperture diameter) of the open diameter of the second optical system 310 and the target brightness AV0(1) at a target control amount 0 of the first optical system 210. Next, the target brightness as the target light intensity of the second aperture 330 is corrected from AV1(2) to AV5(2) to AV1(1) to AV5(1), respectively, based on the calculated difference. Then, corrected target control amounts 1b to 5b are determined as the target aperture diameter of the aperture, which is the second light intensity adjustment device 302, corresponding to the target brightnesses AV1(1) to AV5(1) as the corrected target light intensity, respectively.

[0040] Tables 1 and 2 show the first drive instruction table 250 and the second drive instruction table 350, respectively, for the interchangeable lens 2 according to this embodiment. That is, Tables 1 and 2 are tables showing the target brightness plus zoom correction amount, the corresponding target control amount, and the corresponding correction target control amount for the first optical system 210 and the second optical system 310, respectively, in the TELE state.

[0041] [Table 1]

[0042] [Table 2]

[0043] FIG. 3 is a diagram showing the relationship between the correction control amount of the first aperture 230 and the second aperture 330 and the brightness at the corresponding actual aperture positions when the first zoom lens group 220 and the second zoom lens group 320 are at the telephoto end position (TELE state). In FIG. 3, the horizontal axis represents the correction target control amount, and the vertical axis represents the target brightness. As shown in FIG. 3, in the interchangeable lens 2 according to this embodiment, it is possible to set a predetermined brightness at the corresponding actual aperture positions of the first aperture 230 and the second aperture 330. In other words, by setting the target brightness of the second optical system 310 based on the target brightness of the first optical system 210, it is possible to reduce the difference in brightness between the first optical system 210 and the second optical system 310.

[0044] The first drive instruction table 250 and the second drive instruction table 350 determined as shown in Table 1 and Table 2 are stored as correction tables in the storage unit 600. When the interchangeable lens 2 is used, the camera microcomputer 140 reads out the correction tables from the storage unit 600.

[0045] Next, target brightnesses of the first optical system 210 and the second optical system 310 are set based on instructions from the camera microcomputer 140, and the lens microcomputer 500 determines the corresponding correction target control amount by referencing a correction table. The lens microcomputer 500 then controls the driving of the first aperture driver 240 and the second aperture driver 340 based on the determined correction target control amount. This allows the aperture diameters of the first aperture 230 and the second aperture 330 to be set with high precision.

[0046] As described above, by referring to the first drive instruction table 250 and the second drive instruction table 350, the difference in brightness between the first optical system 210 and the second optical system 310 in the TELE state can be reduced.

[0047] Next, a description will be given of reducing the difference in brightness between the first optical system 210 and the second optical system 310 at other zoom positions (ZP) using the first driving range table 260. Table 3 shows the first driving range table 260. The first driving range table 260 shows the relationship between the zoom position 261 of the first zoom lens group 220 detected by the position detection unit 400 and the read position that is the start of the driving range (driving range start position 262, drive start position).

[0048] [Table 3]

[0049] First, referring to Fig. 4, the driving of the first aperture 230 when the position (zoom position) of the first zoom lens group 220 changes will be described. Fig. 4 is a diagram showing the relationship between the zoom position of the first zoom lens group 220 and the correction target control amount of the first aperture 230. When the first zoom lens group 220 is in the TELE state, the target brightness and the corresponding correction target control amount are determined as the first drive instruction table 250 by the correction method described above.

[0050] Next, referring to ZP1 in the first drive range table 260 in Table 3, the drive range start position 262 is "+1." This means that, as shown in FIG. 4, at zoom position ZP1, by changing the drive start position by the control amount of "+1," it is possible to maintain the same aperture value even when the focal length changes. In other words, at zoom position ZP1, correction target control amount 1a corresponds to AV0(1), and correction target control amount 2a corresponds to AV1(1). Hereinafter, when the drive start positions are written as +1, +2, ..., the correction target control amounts corresponding to AV0(1) or AV0(2) are 1a, 2a, .... Similarly, when the state changes to the WIDE state (wide-angle end position), correction target control amount 5a corresponds to AV0(1), as shown in FIG. 4. In other words, when the first optical system 210 is in the WIDE state, the drive instruction table shown in Table 4 is used.

[0051] [Table 4]

[0052] Next, with reference to Fig. 5, the driving of the second diaphragm 330 when the position (zoom position) of the second zoom lens group 320 changes will be described. Fig. 5 is a diagram showing the relationship between the position of the second zoom lens group 320 and the correction target control amount. For reasons that will be described later, the second diaphragm 330 drives the diaphragm during zooming using the zoom position 261 of the first zoom lens group 220 and the first driving range table 260 used for the first diaphragm 230. In other words, the second diaphragm 330 drives the diaphragm during zooming without using the position of the second zoom lens group 320 and a driving range table dedicated to the second optical system 310.

[0053] When the second zoom lens group 320 is in the TELE state, the target brightness matched to the first optical system 210 and the corresponding correction control amount are determined as the second drive instruction table 350 by the correction method described above.

[0054] Next, referring to ZP1 in the first driving range table 260 of Table 3, the starting position 262 of the driving range is "+1." This means that, as shown in FIG. 5, by changing the aperture diameter by the control amount "+1" at the zoom position ZP1, it is possible to maintain the same aperture value even when the focal length changes. Similarly, when the state changes to the WIDE state, as shown in FIG. 5, the correction target control amount 5b corresponds to AV0(2). In other words, when the second optical system 310 is in the WIDE state, the driving instruction table shown in Table 5 is used. In this way, the second aperture 330 is driven based on the position of the first zoom lens group 220 detected by the position detection unit 400 and the first driving range table 260.

[0055] [Table 5]

[0056] Next, a method for creating the first driving range table 260 will be described with reference to FIGS. 6 and 7. FIG. 6 is a diagram in which the relationship between the target brightness and the aperture diameter at each zoom position ZP of the first optical system 210 is plotted using dashed lines, with the horizontal axis representing the target brightness and the vertical axis representing the correction target control amount (aperture diameter). As shown in FIG. 6, in order to maintain the same brightness when the first zoom lens group 220 moves, it is necessary to change the aperture diameter of the first diaphragm 230. Here, Φ1 to Φ5 differ from the actual aperture diameters and are aperture diameters corresponding to the correction target control amount. Φ1 is the largest, followed by Φ2 and Φ3, in that order.

[0057] Fig. 7 is a plot of the relationship between the target brightness and the corrected target control amount when the start positions of the first drive instruction table 250 are set to +1 and +2. In Fig. 7, the horizontal axis represents the target brightness, and the vertical axis represents the corrected target control amount (aperture diameter). As shown in Fig. 7, when comparing the target brightness at zoom position ZP1 with the target brightness when the start positions are set to +1 and +2, the error is smaller when the start position is set to +1 than when the start position is set to +2.

[0058] Specifically, the brightness corresponding to the corrected target control amount 1a is calculated when the starting position is set to +1. Because the aperture diameter corresponding to the corrected target control amount 1a is Φ1, the brightness is AV0(1)+1 based on the relationship between the target brightness and aperture diameter at ZP1. Similarly, when the starting position is set to +2, the brightness is AV0(1)+2.

[0059] 7, when the error with respect to the target brightness AV0(1) is considered, AV0(1)+2-AV0(1)>AV0(1)+1-AV0(1), the error is smaller when the start position is set to +1 than when the start position is set to +2. Similarly, for each ZP and WIDE, the start position of the first drive instruction table 250 is changed to calculate the value that results in the smallest error, and this is stored as the first drive range table 260.

[0060] As described above, in this embodiment, at a specific zoom position ZP (TELE in this embodiment), as shown in FIG. 3 , corrected target control amounts are set for the first aperture 230 and the second aperture 330 in the first optical system 210 and the second optical system 310, respectively. This makes it possible to set a predetermined brightness in each of the first optical system 210 and the second optical system 310, and to make the brightness change uniform between the first optical system 210 and the second optical system 310. Therefore, it is possible to reduce the difference in brightness between two images acquired via the first optical system 210 and the second optical system 310, respectively. In other words, according to this embodiment, by taking into account optical variations in each optical system, it is possible to provide a compound eye optical system that can be controlled with high-precision light intensity, and that can reduce the difference in light intensity between each image acquired by specifying the same brightness.

[0061] In addition, when the zoom position ZP changes, the first aperture 230 and the second aperture 330 change the start positions of the first drive instruction table 250 and the second drive instruction table 350, respectively, based on the common first drive range table 260 and information from the position detection unit 400. This makes it possible to reduce the data capacity compared to, for example, a method in which the first drive instruction table 250 and the second drive instruction table 350 are held for all zoom positions ZP.

[0062] Specifically, assuming that the zoom position ZP is divided into 20 parts, if the first drive instruction table 250 and the second drive instruction table 350 are to be held for all zoom positions ZP, 20×2=40 pieces of data are required. On the other hand, in this embodiment, processing is possible with only three pieces of data: the first drive instruction table 250, the second drive instruction table 350, and the first drive range table 260.

[0063] Furthermore, by using a common first driving range table 260, it is possible to respond to changes in the zoom position ZP while maintaining a small difference in brightness between the first optical system 210 and the second optical system 310 created at a specific zoom position ZP.

[0064] Next, it will be explained that when dedicated driving range tables are prepared for the first optical system 210 and the second optical system 310, the difference in brightness between the first optical system 210 and the second optical system 310 becomes larger than when the first driving range table 260 in this embodiment is shared. Table 6 shows the second driving range table (third data) 360 created for the second optical system 310 by the method described above.

[0065] [Table 6]

[0066] The second driving range table 360 ​​is obtained from the second driving instruction table 350 and the relationship between the target brightness and the aperture diameter for each zoom position ZP of the second zoom lens group 320. Here, since the first optical system 210 and the second optical system 310 have slightly different transmittances and focal lengths, the first driving range table 260 and the second driving range table 360 ​​do not match, but have slight differences.

[0067] FIG. 8 is a diagram showing the relationship between the target brightness and the correction target control amount for the first aperture 230 and the second aperture 330 at zoom position ZP2. In FIG. 8, the horizontal axis represents the correction target control amount and the target brightness, respectively. From Tables 3 and 6, at zoom position ZP2, the start position for the first aperture 230 is +1, and the start position for the second aperture 330 is +2. Therefore, as shown in FIG. 8, the start positions for the first aperture 230 and the second aperture 330 are different from each other, resulting in a large difference in brightness.

[0068] As described above, if drive range tables are prepared separately for the first optical system 210 and the second optical system 310, the start positions may differ due to optical and mechanical factors. As a result, the difference in brightness between the first optical system 210 and the second optical system 310 may become larger. In contrast, in this embodiment, a common first drive range table 260 is used, so the start positions do not differ, and the difference in brightness between the first optical system 210 and the second optical system 310 can be reduced. Additionally, when zoom position ZP1 is changed to zoom position ZP2, as shown in Tables 2 and 5, the first aperture 230 does not move because its start position does not change, but the second aperture 330 moves because its start position does change. In such a case, the brightness changes on only one side of the left and right optical systems, causing discomfort to the user.

[0069] Next, consider a case where the position detection unit 400 is provided in the second zoom lens group 320 instead of the first zoom lens group 220. Hereinafter, the position detection unit that detects the position of the first zoom lens group 220 will be referred to as the first position detection unit, and the position detection unit that detects the position of the second zoom lens group 320 will be referred to as the second position detection unit. In this embodiment, the first diaphragm 230 and the second diaphragm 330 are driven during zooming based on a first driving range table 260 created with the first optical system 210 as the reference and the position of the first zoom lens group 220 detected using the first position detection unit. However, this embodiment is not limited to this. In other words, the first diaphragm 230 and the second diaphragm 330 may be driven during zooming based on a second driving range table 360 ​​created with the second optical system 310 as the reference and the position of the second zoom lens group 320 detected using the second position detection unit. Even in this case, it is possible to obtain the same effect as when the first optical system 210 is used as the reference. That is, in this embodiment, the configurations and processes of the first optical system 210 and the second optical system 310 are interchangeable.

[0070] Next, consider a case where the position detection unit 400 (first position detection unit, second position detection unit) detects the position of the second zoom lens group 320 in addition to the position of the first zoom lens group 220 to control the driving of each of the first zoom lens group 220 and the second zoom lens group 320. In this case, the first diaphragm 230 is driven using the position of the first zoom lens group 220 detected by the first position detection unit and the first driving range table 260. Similarly, the second diaphragm 330 is driven using the position of the second zoom lens group 320 detected by the second position detection unit and the first driving range table 260. Even in this case, the difference in brightness between the first optical system 210 and the second optical system 310 becomes large, just as in the case where dedicated driving range tables are provided for each of the first optical system 210 and the second optical system 310.

[0071] The two position detection units may be, for example, optical sensors that reflect light emitted from the sensor off a scale and read the reflected light. When using such optical sensors, variations in the position of the sensor unit, variations in the attachment of the scale, or play in the zoom lens groups may result in different sensor outputs even when the first zoom lens group 220 and the second zoom lens group 320 receive the same drive command. If different zoom positions ZP are output from the two position detection units, the start positions of the first aperture 230 and the second aperture 330 may differ according to the first drive range table 260, resulting in a larger difference in brightness as described above.

[0072] As described above, even if a position detection unit is provided in each of the first optical system 210 and the second optical system 310, the difference in brightness can be reduced by driving the first aperture 230 and the second aperture 330 based on the zoom position information of one side.

[0073] (Other embodiments) 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. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0074] According to each embodiment, it is possible to provide a lens device, an imaging device, a control method for a lens device, and a program that can reduce the difference in light intensity between two optical systems in a stereo zoom lens and suppress changes in light intensity during zooming.

[0075] The disclosure of each embodiment includes the following configurations and methods. (Configuration 1) a first optical system having a first zoom lens and a first aperture stop; a second optical system arranged in parallel with the first optical system and having a second zoom lens and a second aperture stop; a position detection unit that detects the position of the first zoom lens; a control unit that controls the aperture diameters of the first aperture diaphragm and the second aperture diaphragm, The lens device, wherein the control unit controls the aperture diameters of the first aperture diaphragm and the second aperture diaphragm based on the position of the first zoom lens. (Configuration 2) The lens device described in configuration 1, characterized in that the control unit controls the aperture diameters of the first aperture diaphragm and the second aperture diaphragm without using data that changes depending on the position of the second zoom lens. (Configuration 3) The control unit changing the aperture diameter of the first aperture stop using the first data and the third data; changing the aperture diameter of the second aperture stop using the second data and the third data; the first data indicates a relationship between a first target light amount of the first optical system and a first drive instruction value of the first aperture stop when the first zoom lens is at a predetermined position, the second data indicates a relationship between a second target light amount of the second optical system and a second drive instruction value of the second aperture stop when the second zoom lens is at the predetermined position, 3. The lens device according to configuration 1 or 2, wherein the third data indicates a relationship between the position of the first zoom lens and a shift amount from the first drive instruction value. (Configuration 4) The lens device described in Configuration 3, wherein the control unit shifts each of the first drive instruction value and the second drive instruction value by the shift amount depending on the position of the first zoom lens. (Configuration 5) 5. The lens device according to configuration 3 or 4, further comprising a storage unit that stores the first data, the second data, and the third data. (Configuration 6) 6. The lens device according to any one of configurations 3 to 5, wherein the third data is data created without using data related to the second zoom lens. (Configuration 7) The lens device described in any one of configurations 3 to 6, wherein the first data is data created based on the amount of light of the first optical system measured while changing the aperture diameter of the first aperture stop. (Configuration 8) The lens device described in any one of configurations 3 to 7, wherein the second data is data created based on the amount of light of the second optical system measured while changing the aperture diameter of the second aperture stop. (Configuration 9) 9. The lens device according to any one of configurations 1 to 8, wherein the position detection section detects the position of the second zoom lens in addition to the position of the first zoom lens. (Configuration 10) An imaging device comprising the lens device according to any one of configurations 1 to 9 and an imaging element. (Method 1) A method for controlling a lens apparatus including a first optical system having a first zoom lens and a first aperture stop, and a second optical system having a second zoom lens and a second aperture stop, arranged in parallel with the first optical system, comprising: a detecting step of detecting a position of the first zoom lens; a control step of controlling the aperture diameters of the first aperture stop and the second aperture stop, a control step of controlling the aperture diameters of the first aperture diaphragm and the second aperture diaphragm based on the position of the first zoom lens detected in the detection step; (Configuration 11) A program that causes a computer to execute the lens device control method described in Method 1.

[0076] Although the 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 the gist of the present invention. [Explanation of symbols]

[0077] 2 Interchangeable lenses (lens devices) 210 1st optical system 220 First zoom lens group (first zoom lens) 230 1st aperture (1st aperture stop) 310 Second optical system 320 Second zoom lens group (Second zoom lens) 330 2nd aperture (2nd aperture stop) 400 Position detection unit 500 Lens microcomputer (control unit)

Claims

1. a first optical system having a first zoom lens and a first aperture stop; a second optical system arranged in parallel with the first optical system and having a second zoom lens and a second aperture stop; a position detection unit that detects the position of the first zoom lens; a control unit that controls the aperture diameters of the first aperture diaphragm and the second aperture diaphragm, The lens apparatus, wherein the control unit controls the aperture diameters of the first aperture stop and the second aperture stop based on the position of the first zoom lens.

2. 2. The lens device according to claim 1, wherein the control unit controls the aperture diameters of the first aperture diaphragm and the second aperture diaphragm without using data that changes depending on the position of the second zoom lens.

3. The control unit changing the aperture diameter of the first aperture stop using the first data and the third data; changing the aperture diameter of the second aperture stop using the second data and the third data; the first data indicates a relationship between a first target light amount of the first optical system and a first drive instruction value of the first aperture stop when the first zoom lens is at a predetermined position; the second data indicates a relationship between a second target light amount of the second optical system and a second drive instruction value of the second aperture stop when the second zoom lens is at the predetermined position, 2. The lens device according to claim 1, wherein the third data indicates a relationship between the position of the first zoom lens and a shift amount from the first drive instruction value.

4. 4. The lens device according to claim 3, wherein the control unit shifts each of the first drive instruction value and the second drive instruction value by the shift amount in accordance with the position of the first zoom lens.

5. 4. The lens device according to claim 3, further comprising a storage unit that stores the first data, the second data, and the third data.

6. 4. The lens device according to claim 3, wherein the third data is data created without using data relating to the second zoom lens.

7. 4. The lens device according to claim 3, wherein the first data is data created based on the amount of light of the first optical system measured while changing the aperture diameter of the first aperture stop.

8. 4. The lens apparatus according to claim 3, wherein the second data is data created based on the amount of light of the second optical system measured while changing the aperture diameter of the second aperture stop.

9. 2. The lens device according to claim 1, wherein the position detection unit detects the position of the second zoom lens in addition to the position of the first zoom lens.

10. An imaging device comprising: a lens device according to claim 1; and an imaging element.

11. A method for controlling a lens apparatus including a first optical system having a first zoom lens and a first aperture stop, and a second optical system having a second zoom lens and a second aperture stop, arranged in parallel with the first optical system, comprising: a detecting step of detecting a position of the first zoom lens; a control step of controlling the aperture diameters of the first aperture stop and the second aperture stop, a control step of controlling the aperture diameters of the first aperture stop and the second aperture stop based on the position of the first zoom lens detected in the detection step;

12. A program for causing a computer to execute the lens apparatus control method according to claim 11.

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