Control apparatus, lens apparatus, method for control, and program

Abstract

To provide a control apparatus capable of realizing smooth driving with reduced speed fluctuation of an optical member.SOLUTION: A driving apparatus is a control apparatus for controlling a driving unit for driving an optical member, and includes: a first acquisition unit configured to acquire the target speed of the optical member; a second acquisition unit configured to acquire the driving speed of the optical member during driving; and a control unit configured to perform first control by transmitting a first output value based on the target speed and the driving speed to the driving unit to control the driving unit so that the driving speed becomes the target speed, the control unit reducing the variation amount of the first output value in accordance with a decrease in the target speed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a control device for controlling a drive unit that drives an optical member. [Background technology]

[0002] Conventionally, configurations have been proposed for achieving smooth driving of optical elements. A smooth driving means, for example, smooth acceleration and deceleration when starting and stopping, and a constant driving speed (with little fluctuation) when driving at low speed. Patent Document 1 discloses a configuration for calculating a target speed based on the difference between a target position and a current position of an optical element, and changing a control gain based on the difference between the target speed and the current speed. Patent Document 2 also discloses a configuration for moving the zoom at a constant speed when the amount of change in operation of an operating unit for specifying the zoom movement speed is equal to or less than a predetermined value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6744770 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-232250 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration of Patent Document 1, when the optical member is driven at a constant slow speed, speed fluctuations of the optical member appear in the image output through the lens device. Also, in the configuration of Patent Document 2, it is not possible to suppress speed fluctuations when an operating member that indicates a target position, such as a focus demand, is operated at a constant speed.

[0005] An object of the present invention is to provide a control device that can achieve smooth driving of an optical member with little speed fluctuation. [Means for solving the problem]

[0006] A driving device according to one aspect of the present invention is a control device for controlling a driving unit that drives an optical element, and includes a first acquisition unit that acquires a target speed of the optical element, a second acquisition unit that acquires the driving speed of the optical element while it is being driven, and a control unit that performs first control to control the driving unit so that the driving speed becomes the target speed by transmitting a first output value based on the target speed and the driving speed to the driving unit, and is characterized in that the control unit reduces the amount of fluctuation in the first output value as the target speed decreases.

[0007] Another aspect of the present invention is a driving device, which is a control device for controlling a driving unit that drives an optical element, and includes a first acquisition unit that acquires a target speed of the optical element, a second acquisition unit that acquires the driving speed of the optical element while it is being driven, and a control unit that performs first control to control the driving unit so that the driving speed becomes the target speed by sending a first output value based on the target speed and the driving speed to the driving unit, and is characterized in that the control unit reduces the amount of fluctuation in the first output value as the driving speed decreases. [Effects of the Invention]

[0008] An object of the present invention is to provide a control device that can achieve smooth driving of an optical member with little speed fluctuation. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram of a system according to a first embodiment. [Figure 2] 5 is a flowchart showing setting of a target speed according to the first embodiment. [Figure 3] 10 is a flowchart showing a calculation process of an output value to a drive unit for each fixed drive cycle according to the first embodiment. [Figure 4] 5 is a flowchart showing an output value calculation process in the first control of the first embodiment. [Figure 5] FIG. 10 is a diagram illustrating an example of a preferable relationship between a coefficient and a target speed. [Figure 6]10 is a graph showing the time transition of the target speed during high-speed driving. [Figure 7] 10 is a graph showing the time transition of the current speed during high-speed driving. [Figure 8] 10 is a graph showing the time transition of the target speed during low-speed driving. [Figure 9] 10 is a graph showing the time transition of the current speed during low-speed driving. [Figure 10] 10 is a flowchart showing a process for calculating an output value to a drive unit for each fixed drive cycle according to a second embodiment. [Figure 11] 10 is a flowchart showing a first output value calculation process in a first control according to the second embodiment. [Figure 12] 10 is a flowchart showing a second output value calculation process in a second control of the second embodiment. [Figure 13] 10 is a flowchart showing a target speed calculation process according to the second embodiment. [Figure 14] 10 is a graph showing the time transition of the position of an optical member when the configuration of the second embodiment is not applied. [Figure 15] 10 is a graph showing the time transition of the position of an optical member when the configuration of the second embodiment is applied. [Figure 16] 10 is a flowchart showing a target speed calculation process according to a third embodiment. [Figure 17] 10 is a flowchart showing a second target speed calculation process according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same components, and redundant explanations will be omitted. [First embodiment] 1 is a block diagram of a system according to this embodiment, which includes a first input device 10, a lens device 20, and a camera device 30.

[0011] The first input device 10 is a controller or the like, and is connected to the lens device 20 to transmit target values ​​for driving the optical element 21. The lens device 20 includes the optical element 21, a drive unit 22, a detection unit 23, a calculation unit 24, a communication unit 25, and a storage unit 26. The lens device 20 constitutes an imaging device by being connected to a camera device 30 that includes an image sensor (not shown) that receives a subject image formed by the lens device 20 and a second input device 31 such as an operation button. The second input device 31 transmits target values ​​for driving the optical element 21.

[0012] In this embodiment, the optical member 21 is a zoom lens that adjusts the focal length. The optical member 21 is connected to a driving unit 22 and a detecting unit 23. The driving unit 22 is an actuator such as a motor, and is capable of driving the optical member 21. The detecting unit 23 is capable of detecting the driving speed (current speed) of the optical member 21 during driving.

[0013] In this embodiment, the target value transmitted by the first input device 10 or the second input device 31 is the target speed at which the optical member 21 is driven.

[0014] The calculation unit 24 is a CPU of the lens device 20. The calculation unit 24 includes a first acquisition unit 24a, a second acquisition unit 24b, and a control unit 24c, and controls the operation of each component of the lens device 20. The first acquisition unit 24a acquires a target speed of the optical member 21. The second acquisition unit 24b acquires a drive speed of the optical member 21 being driven from the detection unit 23. The control unit 24c performs first control, which controls the drive unit 22 so that the current speed becomes the target speed, by transmitting an output value (first output value) based on the target speed and the drive speed to the drive unit 22. Note that, although the calculation unit 24 is provided within the lens device 20 in this embodiment, it may be configured as a control device separate from the lens device 20. Furthermore, the camera device or the first input device 10 may be configured to have at least some of the functions of the first acquisition unit 24a, the second acquisition unit 24b, and the control unit 24c.

[0015] In this embodiment, the communication unit 25 is a communication means having electrical contacts. The storage unit 26 is a memory. The calculation unit 24 (first acquisition unit 24a) receives drive commands from the first input device 10 or the second input device 31 via the communication unit 25 and is able to derive a target speed of the optical element 21. The derived target speed is stored in the storage unit 26. The calculation unit 24 is also able to calculate an output value to the driver 22 based on the target speed stored in the storage unit 26 and the current speed of the optical element 21 transmitted from the detection unit 23, and transmit the output value to the driver 22. The output value calculation process is performed at regular drive cycles that allow the driver 22 to control the optical element 21 with good responsiveness. Furthermore, the calculation unit 24 stores the output value in the storage unit 26 at each drive cycle. The output value stored in the previous drive cycle is overwritten, and the latest output value remains in the storage unit 26.

[0016] The setting of the target speed performed by the calculation unit 24 will be described below. Fig. 2 is a flowchart showing the setting of the target speed performed by the calculation unit 24 in this embodiment. The setting of the target speed is started when the calculation unit 24 receives a drive command transmitted from the first input device 10 or the second input device 31. In this embodiment, the target value shown in Fig. 2 represents the target speed.

[0017] In step S201, the calculation unit 24 (first acquisition unit 24a) calculates (acquires) a target speed at which the optical member 21 is driven based on a drive command.

[0018] In step S202, the calculation unit 24 stores the target speed calculated in step S201 in the storage unit .

[0019] As described above, the calculation unit 24 can set a target speed for driving the optical member 21 when receiving a drive command from the first input device 10 or the second input device 31. The drive command may be, but is not limited to, a command that specifies the speed of the optical member 21 (for example, a zoom demand). Furthermore, the method for calculating the target speed in step S201 is not particularly limited.

[0020] The following describes the calculation process of the output value to the driver 22 for each fixed drive cycle, which is performed by the calculator 24. Fig. 3 is a flowchart showing the calculation process of the output value to the driver 22 for each fixed drive cycle, which is performed by the calculator 24 of this embodiment.

[0021] In step S301, the calculation unit 24 (control unit 24c) performs an output value calculation process in the first control, which will be described later.

[0022] In step S302, the calculation unit 24 stores the output value calculated in step S301 in the storage unit .

[0023] In step S303 (control step), the calculation unit 24 transmits the output value calculated in step S301 to the driving unit 22. The driving unit 22 drives based on the transmitted output value. That is, the calculation unit 24 can control the driving unit 22 using the output value.

[0024] As described above, the calculation unit 24 calculates the output value to the driver 22 for each fixed drive cycle, and the driver 22 can drive based on the transmitted output value. Here, the output value stored in the storage unit 26 is only the output value for the latest drive cycle, and the output value for the previous drive cycle is overwritten by the output value for the latest drive cycle.

[0025] Next, a description will be given of the output value calculation process in the first control performed by the calculation unit 24 in step S301 in Fig. 3. Fig. 4 is a flowchart showing the output value calculation process in the first control performed by the calculation unit 24.

[0026] In step S401, the calculation unit 24 calculates the difference between the target speed stored in the storage unit 26 in step S202 of FIG. 2 and the current speed of the optical member 21 detected by the detection unit 23.

[0027] In step S402, the calculation unit 24 calculates a first operation value by multiplying the difference calculated in step S401 by a gain (control gain). When the first operation value is D1, the target speed is V1, the current speed is V2, and the gain is G, the first operation value D1 is calculated using the following equation (1).

[0028] D1 = (V1 - V2) × G (1) In this embodiment, the gain is a constant used to make the drive speed of the drive unit 22 reach a target value.

[0029] In step S403, the calculation unit 24 calculates a second operation value from the target speed and the first operation value. When the first operation value for the nth cycle calculated in step S402 is D1, the second operation value for the nth cycle is D2, and a coefficient is b, the second operation value D2 for the nth cycle is calculated using the following equation (2).

[0030] D2=D1×b (2) Here, the coefficient b is a variable that changes within the range of the following equation (3).

[0031] 0≦b≦1 (3) That is, the absolute value of the second manipulated variable D2 is equal to or less than the absolute value of the first manipulated variable D1. Furthermore, the coefficient b takes a small value (closer to 0) as the target speed V1 decreases. FIG. 5 is a diagram showing an example of a preferable relationship between the coefficient b and the target speed V1. In FIG. 5, the coefficient b is at its minimum value min when the target speed V1 is 0, and monotonically increases with the target speed V1 until it reaches its maximum value 1. That is, the target speed V1' that reaches the maximum value 1 is used as a threshold, and when the target speed V1 is smaller than the target speed V1', the coefficient b is reduced, and control is performed to reduce the second manipulated variable, which is the amount of fluctuation in the output value to the drive unit 22.

[0032] In step S404, the calculation unit 24 calculates an output value to the drive unit 22 from the second operation value calculated in step S403 and the output value stored in the storage unit 26. When the output value for the nth cycle is O(n) and the second operation value for the nth cycle is D2, the output value O(n) for the nth cycle is calculated using the following equation (4).

[0033] O(n)=O(n-1)+D2 (4) According to equation (4), the output value is changed by the second manipulation value for each period and updated, thereby making it possible to drive the optical member 21 at the target speed.

[0034] As a result, the calculation unit 24 calculates the output value to the drive unit 22 in the current drive cycle from the output value to the drive unit 22 in the previous drive cycle, thereby making it possible to drive the optical element 21 smoothly at a constant speed.

[0035] FIG. 6 is a graph showing the time progression of target velocity V1 when an operator operates an operating member to drive optical element 21 (a zoom lens in this embodiment) at a constant operating target velocity A1, and illustrates an example of a trajectory B1 of target velocity V1. The operating target velocity A1 is a high target velocity at which coefficient b in FIG. 5 reaches its maximum value of 1. The operating member may be operated in any manner, but in this embodiment, it may be a zoom lever for zooming. Therefore, operating the operating member to achieve operating target velocity A1 involves pushing the zoom lever to a predetermined angle and maintaining that amount of depression. The operator operates the operating member to achieve operating target velocity A1, but because the degree of depression of the zoom lever changes and the target velocity V1 is calculated based on an analog signal, the trajectory B1 of target velocity V1 actually used in the first control includes noise components, as shown in FIG. 6.

[0036] Fig. 7 is a graph showing the time progression of current speed V2 when target speed V1 fluctuates as shown by trajectory B1 in Fig. 6, and shows an example of a trajectory C1 of current speed V2. In the first control, trajectory B1 containing noise is used as target speed V1, and therefore the output value of the first control and trajectory C1 also contain noise.

[0037] 8 is a graph showing the time progression of target speed V1 when an operator operates an operating member to drive a zoom lens at a constant operation target speed A2, and shows an example of a trajectory B2 of target speed V1. Operation target speed A2 is a slow target speed at which coefficient b is close to the minimum value min in FIG.

[0038] Fig. 9 is a graph showing the time progression of current speed V2 when target speed V1 fluctuates as shown by trajectory B2 in Fig. 8, and shows an example of trajectory C2 of current speed V2. Compared to trajectory C1, trajectory C2 has a smaller coefficient b, which reduces the effect of noise on the output value of the first control, thereby suppressing the amount of fluctuation in the output value of the first control. As a result, fluctuations in the current speed are also suppressed as shown by trajectory C2.

[0039] When it is desired to drive the optical member 21 at high speed, a responsiveness that quickly reaches a desired speed is required, and when it is desired to drive it at low speed, a constant speed capability that drives it at a constant speed is required.

[0040] As shown in Figures 6 and 7, when driving the optical element 21 at high speed, setting the coefficient b high will cause speed unevenness in the optical element 21, but since the responsiveness is high, the target speed can be reached quickly.

[0041] When the optical member 21 is driven at a low speed as shown in FIGS. 8 and 9, by setting the coefficient b low, the responsiveness decreases, but the constant speed of driving at a constant speed improves.

[0042] In this embodiment, the optical member 21 is a zoom lens, but it is not limited to this and may be a focus lens that adjusts the focal position or an aperture blade that adjusts the amount of light. Also, wireless communication means without electrical contacts may be used as the communication unit 25.

[0043] As described above, according to the configuration of this embodiment, even when the command value for driving the optical member 21 has a large noise, smooth driving with little speed fluctuation can be achieved. [Second embodiment] In this embodiment, the same functional configurations as those in the first embodiment are assigned the same reference numerals, and a description thereof will be omitted. The system of this embodiment has a configuration similar to that of the first embodiment. In this embodiment, only the configurations different from those in the first embodiment will be described, and a description of the common configurations will be omitted.

[0044] The optical member 21 is a focus lens that adjusts the focal position.

[0045] The first input device 10 and the second input device 31 transmit drive commands related to the target positions, and the communication unit 25 receives the drive commands. Here, the drive command may be one that specifies the absolute position of the optical member 21 (for example, a focus demand), but is not particularly limited. In addition, the method of calculating the target position (target value) in step S201 is not particularly limited.

[0046] In this embodiment, the calculation unit 24 sets the target position in accordance with the flowchart of Fig. 2, as in the first embodiment. Note that this embodiment differs from the first embodiment in that the target values ​​in steps S201 and S202 are target positions, not target speeds.

[0047] The calculation unit 24 functions as a third acquisition unit that acquires the target position of the optical member 21 and a fourth acquisition unit that acquires the position of the optical member 21. The control unit 24c performs second control to control the drive unit 22 by transmitting an output value to the drive unit 22 so that the position of the optical member 21 becomes the target position.

[0048] The detection unit 23 detects the current position of the optical element 21, and the calculation unit 24 calculates the output value to the drive unit 22 based on the target position stored in the storage unit 26 and the current position of the optical element 21 transmitted from the detection unit 23.

[0049] The following describes the calculation process of the output value to the driver 22 for each fixed drive cycle, which is performed by the calculation unit 24. Fig. 10 is a flowchart showing the calculation process of the output value to the driver 22 for each fixed drive cycle, which is performed by the calculation unit 24 of this embodiment.

[0050] In step S1001, the calculation unit 24 performs a first output value calculation process in the first control, which will be described later.

[0051] In step S1002, the calculation unit 24 stores the first output value calculated in step S1001 in the storage unit .

[0052] In step S1003, the calculation unit 24 performs a second output value calculation process in the second control, which will be described later.

[0053] In step S1004, the calculation unit 24 stores the second output value calculated in step S1003 in the storage unit .

[0054] In step S1005, the calculation unit 24 calculates (obtains) the output value to the drive unit 22 by adding the first output value and the second output value.

[0055] In step S1006, the calculation unit 24 transmits to the driving unit 22 the output value to be output to the driving unit 22 calculated in step S1005.

[0056] As described above, the calculation unit 24 calculates the output value to the driver 22 for each fixed drive cycle. The driver 22 can drive based on the transmitted output value. Here, the output value stored in the storage unit 26 is only the output value for the latest drive cycle, and the output value for the previous drive cycle is overwritten by the output value for the latest drive cycle.

[0057] Next, a description will be given of the first output value calculation process in the first control performed by the calculation unit 24 in step S1001 of Fig. 10. Fig. 11 is a flowchart showing the first output value calculation process in the first control performed by the calculation unit 24.

[0058] In step S1101, the calculation unit 24 calculates the difference between the target position stored in the storage unit 26 in step S202 of FIG.

[0059] In step S1102, the calculation unit 24 stores the difference calculated in step S1101 in the storage unit .

[0060] In step S1103, the calculation unit 24 calculates a first output value from the difference stored in step S1102. For example, the calculation unit 24 calculates the first output value using the following equation (5), which multiplies the difference between the target position and the current position by a gain.

[0061] O1=(P1-P2)×G1 (5) Here, O1 is the first output value, P1 is the target position, P2 is the current position, and G1 is the gain.

[0062] As described above, the calculation unit 24 calculates the first output value in the first control for each fixed drive cycle.

[0063] Next, a description will be given of the second output value calculation process in the second control performed by the calculation unit 24 in step S1003 in Fig. 10. Fig. 11 is a flowchart showing the second output value calculation process in the second control performed by the calculation unit 24.

[0064] In step S1201, the calculation unit 24 performs a process of calculating a target velocity of the optical member 21. The target velocity calculation process will be described later.

[0065] In step S1202, the calculation unit 24 calculates the difference between the target speed calculated in step S1201 and the current speed of the optical member 21. Here, the method for calculating the current speed is not particularly limited.

[0066] In step S1203, the calculation unit 24 calculates the operation value based on the difference calculated in step S1202. When the operation value is Op, the target speed is V1, the current speed is V2, and the gain is G2, the operation value Op is calculated using the following equation (6).

[0067] Op = (V1 - V2) × G2 (6) In step S1204, the calculation unit 24 calculates the second output value based on the manipulation value calculated in step S1203. When the second output value in the nth cycle is O(n) and the second output value in the n-1th cycle is O(n-1), the second output value O(n) in the nth cycle is calculated using the following equation (7).

[0068] O2(n)=O2(n-1)+Op (7) As described above, the calculation unit 24 calculates the second output value in the second control for each fixed drive cycle.

[0069] Next, a description will be given of the target velocity calculation process performed by the calculation unit 24 in step S1201 of Fig. 12. Fig. 13 is a flowchart showing the target velocity calculation process performed by the calculation unit 24.

[0070] In step S1301, the calculation unit 24 calculates a target speed at which the optical member 21 is driven from the difference between the target position saved in step S1102 of FIG. 11 and the current position.

[0071] In step S1302, the calculation unit 24 determines whether the current speed of the optical element 21 is greater than a preset first threshold. If the calculation unit 24 determines that the current speed of the optical element 21 is greater than the first threshold, it ends this flow, but if it determines that the current speed is not greater than the first threshold, it executes the processing of step S1303. Note that if the current speed of the optical element 21 is equal to the first threshold, it is possible to arbitrarily set which step to execute.

[0072] In step S1303, the calculation unit 24 determines whether the current speed of the optical element 21 is greater than a preset second threshold. If the calculation unit 24 determines that the current speed of the optical element 21 is greater than the first threshold, it executes the process of step S1304. If the calculation unit 24 determines that the current speed of the optical element 21 is not greater than the first threshold, it executes the process of step S1306. Note that when the current speed of the optical element 21 is equal to the second threshold, it is possible to arbitrarily set which step to execute.

[0073] In step S1304, the calculation unit 24 determines whether the target speed calculated in step S1301 is greater than the current speed of the optical element 21. If the calculation unit 24 determines that the target speed is greater than the current speed of the optical element 21, it executes the processing of step S1305, and if it determines that the target speed is not greater than the current speed of the optical element 21, it ends this flow. Note that if the target speed is equal to the current speed of the optical element 21, it is possible to arbitrarily set which step to execute.

[0074] In step S1305, the calculation unit 24 changes the target speed calculated in step S1301 to the current speed.

[0075] In step S1306, the calculation unit 24 determines whether the target speed calculated in step S1301 is greater than a preset second threshold. If the calculation unit 24 determines that the target speed is greater than the second threshold, it executes the process of step S1307. If the calculation unit 24 determines that the target speed is not greater than the second threshold, it executes this flow. Note that if the target speed is equal to the second threshold, it is possible to arbitrarily set which step to execute.

[0076] In step S1307, the calculation unit 24 changes the target speed calculated in step S1301 to the second threshold value.

[0077] As a result, during constant speed driving where the current speed is smaller than the first threshold value, the calculation unit 24 sets the upper limit of the target speed calculated from the difference between the target position and the current position as the current speed, thereby enabling smooth driving during low speed driving and highly accurate driving to the target position.

[0078] Here, the first threshold is a threshold set in advance to determine whether the speed is equal to or greater than a predetermined speed, and can be set to any value. However, since a speed greater than the first threshold will result in highly accurate driving to the target position, and a speed smaller than the first threshold and greater than the second threshold will result in driving to maintain the current speed, it is preferable to set the first threshold to a speed that requires constant speed.

[0079] The second threshold is an arbitrary value smaller than the first threshold, but it is preferable to set the speed to a sufficiently small value that constant speed is not required, in order to perform highly accurate driving to the target position at a speed smaller than the second threshold.

[0080] Fig. 14 is a graph showing the time transition of the position of the optical member 21 when the configuration of this embodiment is not applied, and Fig. 15 is a graph showing the time transition of the position when the configuration of this embodiment is applied.

[0081] 14 and 15, a locus A represents the locus of the target position of the optical member 21. The speed of change of the target position represented by the slope of the locus A is assumed to be smaller than a first threshold value.

[0082] 14, trajectory B represents the trajectory of the optical element 21 when general proportional control is performed, in which the value obtained by multiplying the position deviation by a gain is used as the output, as in the first control of this embodiment. The trajectory B driven by proportional control is driven at the same speed as the target position (trajectory A) while being driven, but the steady-state deviation during driving and after stopping is large, and the stopping accuracy is poor.

[0083] 14, trajectory C represents the trajectory of the optical element 21 when proportional-integral control is performed, in which the output of integral control, in which a value based on the position deviation is added to the previous output, is added to the output of the proportional control described above. The trajectory C driven by proportional-integral control has a small steady-state deviation and good stopping accuracy due to the addition of an integral element, but the speed fluctuation during driving is large, which gives the user a poor feel when operating it.

[0084] In FIG. 15, trajectory D represents the trajectory that the optical element 21 follows relative to the target position. Since the current velocity is zero at the start of movement in trajectory D, the second threshold value is set as the upper limit of the target velocity in the second control (step S1307 in FIG. 13), and the second output value is added to reach the target position. If the current velocity is greater than the second threshold value and less than the first threshold value when movement starts, the target velocity is changed to the current velocity in the second control (step S1305 in FIG. 13). Therefore, the operation value calculated in step S1203 in FIG. 12 becomes zero, and the second output value continues to maintain the value of the previous drive cycle. Therefore, the optical element 21 can continue to be driven at a constant velocity while maintaining a difference between the target position and the current position. Furthermore, when the target position stops, the target speed calculated from the difference between the target position and the current position becomes smaller, and in step S1304 of FIG. 13, the target speed becomes smaller than the current speed, so that addition and subtraction to the second output value is resumed, making it possible to reach the target position.

[0085] As described above, the configuration of this embodiment enables highly accurate driving to a target position, and smooth driving with little speed fluctuation at low speeds where constant speed is required.

[0086] In this embodiment, the optical member 21 is a focus lens, but is not limited to this and may be a zoom lens that adjusts the focal length or an aperture blade that adjusts the amount of light.

[0087] In addition, in this embodiment, the output value to the drive unit 22 is the sum of the first output value, which is the control result of the first control, and the second output value, which is the control result of the second control. However, it is also possible to perform only the second control and output the second output value directly to the drive unit 22.

[0088] The second control is not limited to the control method of this embodiment, and may be any control that includes the role of integral control for reaching the target position. For example, the second control may be a control method in which a value obtained by multiplying a gain by the difference between the target position and the current position is added to the second output value of the previous drive cycle.

[0089] As described above, according to the configuration of this embodiment, in position control for driving to a target position, the upper limit of the target speed is set using the current speed, making it possible to achieve both highly accurate driving to the target position and smooth driving. [Third embodiment] In this embodiment, the same functional configurations as those in the first and second embodiments are assigned the same reference numerals, and a description thereof will be omitted. The system of this embodiment has a configuration similar to that of the first and second embodiments. In this embodiment, only the configurations different from those in the first and second embodiments will be described, and a description of the common configurations will be omitted.

[0090] Next, a description will be given of the target velocity calculation process performed by the calculation unit 24 in step S1201 of Fig. 12. Fig. 16 is a flowchart showing the target velocity calculation process performed by the calculation unit 24.

[0091] In step S1601, the calculation unit 24 determines whether the target position input to the calculation unit 24 is noisy. If the target position is calculated based on an analog signal, the calculation unit 24 determines that it is noisy, and if it is calculated based on a digital signal, the calculation unit 24 determines that it is not noisy. If the calculation unit 24 determines that the target position is noisy, it executes the process of step S1602, and if it determines that it is not noisy, it executes the process of step S1603.

[0092] In step S1602, the calculation unit 24 calculates the target velocity by performing a first target velocity calculation process using the current velocity of the optical member 21. The first target velocity calculation process is similar to the target velocity calculation process described in the second embodiment.

[0093] In step S1603, the calculation unit 24 performs a second target velocity calculation process using the amount of fluctuation of the target position to calculate the target velocity.

[0094] Next, a description will be given of the second target velocity calculation process performed by the calculation unit 24 in step S1603 of Fig. 16. Fig. 17 is a flowchart showing the second target velocity calculation process performed by the calculation unit 24.

[0095] In step S1701, the calculation unit 24 calculates the target position from the difference between the target position and the current position. The target speed is calculated in the same manner as in step S1301 in FIG.

[0096] In step S1702, the calculation unit 24 calculates the upper limit of the target speed from the amount of fluctuation of the target position. Because the target position is updated for each drive cycle, it is possible to calculate the fluctuation speed of the target position from the amount of fluctuation of the target position over multiple drive cycles. The calculation unit 24 sets the fluctuation speed of the target position as the upper limit of the target speed.

[0097] In step S1703, the calculation unit 24 determines whether the target speed is smaller than the upper limit. If the calculation unit 24 determines that the target speed is smaller than the upper limit, it ends this flow. If the calculation unit 24 determines that the target speed is not smaller than the upper limit, it executes the processing of step S1704. Note that if the target speed is equal to the upper limit, it is possible to arbitrarily set which step to execute.

[0098] In step S1704, the calculation unit 24 changes the target speed to the upper limit value.

[0099] Here, the difference between the target speed calculated using the current speed (FIG. 13) and the target speed calculated from the amount of fluctuation in the target position will be explained.

[0100] If the target position is not noisy, calculating the target speed from the fluctuating speed of the target position rather than calculating it from the current speed allows the target speed to be set more accurately, thereby enabling smoother driving.

[0101] If the target speed is noisy, the speed of change of the target position cannot be calculated accurately, and therefore the target speed cannot be set accurately. Therefore, when performing position control based on a noisy target position, calculating the target speed using the current speed enables smoother driving.

[0102] In this embodiment, whether the target position is noisy or not is determined based on whether the signal used to calculate the target position is an analog signal or a digital signal, but this is not limiting. For example, the variation in the target position over multiple drive cycles may be calculated, and the determination may be made based on whether the variation is equal to or greater than a predetermined range.

[0103] As described above, the configuration of this embodiment makes it possible to achieve both highly accurate driving to the target position and smooth driving, both when the target position is noisy and when it is not noisy. [Other Examples] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0104] The disclosure of this embodiment includes the following configurations and methods. (Configuration 1) A control device for controlling a drive unit that drives an optical member, a first acquisition unit that acquires a target velocity of the optical member; a second acquisition unit that acquires a drive speed of the optical member during driving; a control unit that performs first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control device is characterized in that the control unit reduces a fluctuation amount of the first output value in response to a decrease in the target speed. (Configuration 2) 2. The control device according to configuration 1, wherein the control unit reduces the amount of fluctuation when the target speed becomes smaller than a threshold value. (Configuration 3) 3. The control device according to configuration 1 or 2, wherein the control unit reduces the amount of fluctuation by reducing a control gain. (Configuration 4) A control device for controlling a drive unit that drives an optical member, a first acquisition unit that acquires a target velocity of the optical member; a second acquisition unit that acquires a drive speed of the optical member during driving; a control unit that performs first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control device is characterized in that the control unit reduces a fluctuation amount of the first output value in response to a decrease in the drive speed. (Configuration 5) 5. The control device according to configuration 4, wherein the control unit reduces the amount of fluctuation when the drive speed becomes smaller than a threshold value. (Configuration 6) 6. The control device according to configuration 4 or 5, wherein the control unit reduces the amount of fluctuation by setting the target speed based on the drive speed. (Configuration 7) a third acquisition unit that acquires the position of the optical member; a fourth acquisition unit that derives a target position of the optical member, 7. The control device according to any one of configurations 1 to 6, wherein the control unit performs second control to control the drive unit so that the position becomes the target position. (Configuration 8) The control device according to configuration 7, characterized in that when the control unit performs the second control in a first drive cycle, the control unit outputs to the drive unit a value based on a value obtained by adding a value based on a difference between the position and the target position and a value based on a control result of the second control in a second drive cycle that precedes the first drive cycle. (Configuration 9) A control device according to any one of configurations 1 to 8; an optical member; and a drive unit that drives the optical member. (Method 1) A control method for controlling a drive unit that drives an optical member, comprising: obtaining a target velocity of the optical element; acquiring a driving speed of the optical member during driving; a control step of performing first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control method is characterized in that, in the control step, a fluctuation amount of the first output value is reduced in accordance with a decrease in the target speed. (Method 2) A control method for controlling a drive unit that drives an optical member, comprising: obtaining a target velocity of the optical element; acquiring a driving speed of the optical member during driving; a control step of performing first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control method is characterized in that, in the control step, a fluctuation amount of the first output value is reduced in accordance with a decrease in the drive speed. (Configuration 10) A program causing a computer to execute the control method according to Method 1 or 2.

[0105] 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]

[0106] 21 Optical Components 22 Drive unit 24 Calculation unit (control device) 24a First Acquisition Section 24b Second Acquisition Section 24c Control Unit

Claims

1. A control device for controlling a drive unit that drives an optical member, a first acquisition unit that acquires a target velocity of the optical member; a second acquisition unit that acquires a drive speed of the optical member during driving; a control unit that performs first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control device is characterized in that the control unit reduces a fluctuation amount of the first output value in response to a decrease in the target speed.

2. The control device according to claim 1 , wherein the control unit reduces the amount of fluctuation when the target speed becomes smaller than a threshold value.

3. 3. The control device according to claim 1, wherein the control unit reduces the amount of fluctuation by reducing a control gain.

4. A control device for controlling a drive unit that drives an optical member, a first acquisition unit that acquires a target velocity of the optical member; a second acquisition unit that acquires a drive speed of the optical member during driving; a control unit that performs first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control device is characterized in that the control unit reduces a fluctuation amount of the first output value in response to a decrease in the drive speed.

5. 5. The control device according to claim 4, wherein the control unit reduces the amount of fluctuation when the drive speed becomes smaller than a threshold value.

6. 6. The control device according to claim 4, wherein the control unit reduces the amount of fluctuation by setting the target speed based on the drive speed.

7. a third acquisition unit that acquires the position of the optical member; a fourth acquisition unit that derives a target position of the optical member, 5. The control device according to claim 1, wherein the control unit performs a second control of controlling the drive unit so that the position coincides with the target position.

8. The control device according to claim 7, characterized in that, when performing the second control in a first drive cycle, the control unit outputs to the drive unit a value based on a value obtained by adding a value based on a difference between the position and the target position and a value based on a control result of the second control in a second drive cycle that precedes the first drive cycle.

9. The control device according to claim 1 or 4; an optical member; and a drive unit that drives the optical member.

10. A control method for controlling a drive unit that drives an optical member, comprising: obtaining a target velocity of the optical element; acquiring a driving speed of the optical member during driving; a control step of performing first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control method is characterized in that, in the control step, a fluctuation amount of the first output value is reduced in accordance with a decrease in the target speed.

11. A control method for controlling a drive unit that drives an optical member, comprising: obtaining a target velocity of the optical element; acquiring a driving speed of the optical member during driving; a control step of performing first control to control the drive unit so that the drive speed becomes the target speed by transmitting a first output value based on the target speed and the drive speed to the drive unit, The control method is characterized in that, in the control step, a fluctuation amount of the first output value is reduced in accordance with a decrease in the drive speed.

12. A program causing a computer to execute the control method according to claim 10 or 11.

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