Shake correction control device, imaging device, lens device, imaging system, control method, and storage medium

Abstract

To provide a shake correction control device capable of performing stable shake correction having less noise components included in deflection detection means when performing still image exposure.SOLUTION: A shake correction control device includes: signal processing means 16 for acquiring a shake correction signal from shake detection means 15 for detecting a shake detection signal and performing output by using the acquired shake detection signal; overflow prevention means 18; and control means 12a for controlling a shake correction. The signal processing means comprises: first signal processing means for outputting a first shake correction target value; and second signal processing means for outputting a second shake correction target value in parallel with output of the first signal processing means and having frequency characteristics different from the first signal processing means. The control means controls a shake correction by the second shake correction target value during aiming, and controls a shake correction by the first shake correction target value during still image exposure. The overflow prevention means prevents an operation overflow of the first shake correction target value during aiming.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an anti-shake control device for imaging devices such as digital cameras and digital videos.

Background Art

[0002] Patent Document 1 discloses a technique in which signals from a shake detection means are calculated by two signal processing means with different gains, and an appropriate signal among the two calculated signals is used for shake correction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the technique disclosed in Patent Document 1 is not effective for early removal of noise components included in the shake detection means during still image shooting.

[0005] Therefore, an object of the present invention is to provide an anti-shake control device capable of performing stable anti-shake with few noise components included in the shake detection means when performing still image exposure.

Means for Solving the Problems

[0006] As one aspect of the present invention, an image stabilization control device includes: a shake detection means for detecting a shake detection signal related to shake applied to an imaging device, acquiring the shake detection signal, and outputting a shake correction target value using the shake detection signal; a signal processing means; a control means for controlling shake correction in a direction along an imaging plane by controlling movement of at least one of an imaging element and some lenses included in an imaging optical system based on the shake correction target value; and an overflow prevention means for preventing an arithmetic overflow of the shake correction target value. The signal processing means includes a first signal processing means for outputting a first shake correction target value, and a second signal processing means having frequency characteristics different from those of the first signal processing means, and outputting a second shake correction target value in parallel with the output of the first shake correction target value by the first signal processing means. The first signal processing means includes first integration means for integrating the shake detection signal, When aiming at a subject in preparation for still image exposure, the control means controls the shake correction based on the second shake correction target value, and when performing the still image exposure, the control means controls the shake correction based on the first shake correction target value. The overflow prevention means prevents the first By rewriting the output of the integration means, the arithmetic overflow during the period when the control means controls the shake correction based on the second shake correction target value. processing is performed This is the gist of the present invention.

[0007] Other objects and features of the present invention will be described in the following embodiments.

Advantages of the Invention

[0008] According to the present invention, it is possible to provide an image stabilization control device capable of performing stable image stabilization with few noise components included in shake detection means when performing still image exposure.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Best Mode for Carrying Out the Invention

[0010] Hereinafter, preferred embodiments of the present invention will be described in detail using examples based on the accompanying drawings. (First Embodiment) FIG. 1 shows a cross-section of a camera (imaging system) 11 composed of a camera body (imaging device) 11a and an interchangeable lens (lens device) 11b detachable from the camera body 11a, and a simple control block diagram of an anti-vibration system.

[0011] A camera CPU (control means) 12a provided in the camera body 11a controls a photographing operation and an anti-vibration system operation in the camera in response to a photographing instruction operation from a photographer or the like.

[0012] A subject light beam along the optical axis 10 enters an image sensor 14a, which is an imaging means, through a photographing optical system 13 provided in the interchangeable lens 11b. The image sensor 14a outputs a signal in response to the incident subject light beam.

[0013] 15 is an angular velocity meter which is a shake detection means, and detects a shake detection signal (shake angular velocity) indicated by an arrow 15a applied to the camera 11. The signal of the shake detection means 15 is acquired by the signal processing means 16 and converted into a shake correction target value suitable for shake correction. The signal processing means 16 is composed of a first signal processing means 16a that outputs a first shake correction target value, and a second signal processing means 16b that has different frequency characteristics from the first signal processing means 16a and outputs a second shake correction target value.

[0014] The first and second shake correction target values are switched by a switching means 17 along a shooting sequence described later and input to the driving means 14b. The driving means 14b moves the imaging element 14a in the direction of the arrow 14c based on the shake correction target value from the switching means 17. Thereby, shake correction in the direction along the imaging plane is performed. In this way, the shake correction means 14 is constituted by the imaging element 14a and the driving means 14b.

[0015] Note that the shake detection means 15 also detects a shake detection signal (shake angular velocity) in a direction different from the arrow 15a, and the first and second signal processing means 16a and 16b appropriately generate a blur correction target value for that signal. Then, the driving means 14b moves the imaging element 14a in a suitable direction according to the blur correction target value to perform shake correction in that direction.

[0016] In this embodiment, shake correction is performed by moving the imaging element 14a, but shake correction may also be performed by moving some lenses included in the imaging optical system 13.

[0017] The overflow prevention means 18 prevents an arithmetic overflow of the first signal processing means 16a. The operation of the overflow prevention means 18 will be described later. Note that the camera CPU 12a, the signal processing means 16, and the overflow prevention means 18 are collectively referred to as a shake correction control device. Also, in this embodiment, the shake correction control device is provided in the camera body 11a, but it may be configured to be provided in the interchangeable lens 11b.

[0018] Next, the first and second signal processing means 16a and 16b will be described with reference to FIG. 2.

[0019] In the first signal processing means 16a, the low-frequency component of the signal from the shake detection means 15 is attenuated by a high-pass filter 21a having a large time constant. The signal from the shake detection means 15 that has passed through the high-pass filter 21a is integrated by an integrator 22a and converted into a shake angle signal. Then, the shake angle signal is gain-adjusted by an adjuster 23a with an optical condition such as the focal length of the interchangeable lens 11b and a gain suitable for still image exposure, and converted into a first shake correction target value.

[0020] Since the time constant of the high-pass filter 21a is large, the attenuation ability of the low-frequency component is low, but high-precision low-frequency removal is possible. However, when frequently repeating framing as when aiming at a subject, the shake detection signal does not stabilize, so the operability of the camera 11 cannot be improved.

[0021] In the second signal processing means 16b, the low-frequency component of the signal from the shake detection means 15 is attenuated by a high-pass filter 21b having a small time constant. The signal from the shake detection means 15 that has passed through the high-pass filter 21b is integrated by an integrator 22b and converted into a shake angle signal. Then, the shake angle signal is gain-adjusted by an adjuster 23b with an optical condition such as the focal length of the interchangeable lens 11b and a gain suitable for aiming at a subject, and converted into a second shake correction target value.

[0022] Since the time constant of the high-pass filter 21b is small, the attenuation ability of the low-frequency component is high and the stability is excellent, but the low-frequency component in the shake is also attenuated. Therefore, there is no problem in aiming at a subject, but it is not suitable when high image quality is required such as in still image exposure.

[0023] Next, with reference to FIG. 3, the signal processing waveforms in the above-described first and second signal processing means 16a and 16b will be described in a state where low-frequency noise is superimposed on the shake detection means 15.

[0024] In FIG. 3, the horizontal axis of each graph indicates the elapsed time. The vertical axis will be described in order from the top. The first is the hand shake angular velocity signal detected by the shake detection means 15. The second is the angle signal (second shake correction target value) of the second signal processing means 16b and the angle signal (first shake correction target value) of the first signal processing means 16a. The third is the angle signal that switches from the second shake correction target value to the first shake correction target value when shooting a still image (hereinafter referred to as shooting) after aiming at the subject for preparing the still image exposure (hereinafter referred to as aiming). The fourth is the angle signal by the conventional signal processing.

[0025] Waveform 31 is the hand shake angular velocity signal output by the shake detection means 15, and here it is shown as a single vibration for the sake of explanation. And a low-frequency noise component 31a is superimposed on this waveform 31.

[0026] Waveform 32 is the waveform obtained by converting waveform 31 into an angle signal by the second signal processing means 16b. The low-frequency noise component 31a superimposed on waveform 31 is removed by the high-pass filter 21b in FIG. 2 during section 32a and becomes a stable second shake correction target value. Thus, the reason why the low-frequency noise component 31a can be removed early is that the time constant of the high-pass filter 21b in the second signal processing means is small. However, as described above, waveform 32, which is the second shake correction target value, has high stability and is suitable for aiming but is not suitable for shooting.

[0027] Waveform 33 is the waveform obtained by converting waveform 31 into an angle signal by the first signal processing means 16a. It takes a long time to remove the low-frequency noise component 31a superimposed on waveform 31 by the high-pass filter 21a in FIG. 2. Thus, the reason why it takes time to remove the low-frequency noise component 31a is that the time constant in the first signal processing means 16a is large. Therefore, as described above, waveform 33, which is the first shake correction target value, has low stability and is not suitable for aiming.

[0028] Further, waveform 33 has discontinuity points 33a and 33b. As can be seen from waveform 31, the first shake correction target value, which is waveform 33, has its signal fluctuating due to the influence of the low-frequency noise component 31a. And there is a risk that this fluctuation will become large and an arithmetic overflow will occur. Therefore, when the first shake correction target value of waveform 33 exceeds the overflow threshold 33d (predetermined value), the overflow prevention means 18 subtracts (or adds) a constant bias signal to generate a new shake correction target value. Specifically, when the output of the integrator 22a in FIG. 2 becomes equal to or greater than the predetermined value, a value obtained by subtracting (adding) a constant value from that value is newly set as the output of the integrator 22a.

[0029] Waveform 34 shows the shake correction target value along the shooting sequence of the camera 11. In the aiming sections 34a and 34c, the second shake correction target value of waveform 32 is incorporated, and in the shooting section 34b, the first shake correction target value at the same timing in waveform 33 is incorporated. The shake correction means is driven by these shake correction target values.

[0030] Here, the first and second signal processing means 16a and 16b start operations simultaneously. Waveform 33, which is the signal of the first signal processing means 16a in the section 34b where shooting is performed, is stable because the low-frequency noise component 31a has already been sufficiently removed. For this reason, highly accurate shake correction is performed. Thus, the output of the first shake correction target value by the first signal processing means 16a and the output of the second shake correction target value by the second signal processing means 16b are performed in parallel. Here, if shooting starts at an earlier time point, the shake correction also becomes unstable in the above processing. However, in actual shooting, the aiming time is often set long, so during that time, the influence of the low-frequency noise component 31a on the first shake correction target value is reduced, and the shake correction rarely becomes unstable.

[0031] The waveform 35 is the conventional image stabilization target value, and the aiming periods of the sections 35a and 35c are the same as those in this embodiment. However, in the section 35b, from the start point thereof, the same variation as that in the section 33c of the waveform 33 occurs in the waveform 33 due to the influence of the low-frequency noise component 31a in order for the signal processing means to start calculating the image stabilization target value for shooting, and the image stabilization becomes unstable.

[0032] Thus, in this embodiment, the image stabilization during shooting can be stabilized as time elapses from the start of aiming.

[0033] FIG. 4 shows the control flow of the first and second signal processing means 16a and 16b by the camera CPU (control means) 12a in this embodiment, and this flow starts when the main power of the camera 11 is turned on or when aiming starts.

[0034] In step S401, the shake detection means 15 is activated.

[0035] In step S402, step S402 is looped and waited until the shake detection signal from the shake detection means is stabilized (for example, 0.1 second).

[0036] In step S403, the control means 12a activates the first and second signal processing means 16a and 16b, and starts an operation to convert the shake detection signal from the shake detection means 15 into the first and second image stabilization target values in the first and second signal processing means 16a and 16b.

[0037] As in steps S401 to S403, the first and second signal processing means 16a and 16b are activated after a predetermined time from the activation of the shake detection means 15. Therefore, the initial noise included in the shake detection means 15 is not input to the first and second signal processing means 16a and 16b, and the occurrence of variation in the signal processing means 16 due to the initial noise of the shake detection means 15 is suppressed.

[0038] In step S404, step S404 is looped and waited until the angular signals of the first and second signal processing means 16a and 16b are stabilized (for example, 0.5 seconds).

[0039] In step S405, the control means 12a causes the shake correction means 14 to start aiming shake correction based on the second shake correction target value.

[0040] In step S406, when an instruction to start shooting (start exposure) is given, the process proceeds to step S407; otherwise, the process proceeds to step S411.

[0041] In step S407, the control means 12a adds (or subtracts) a constant value to the first shake correction target value. Thereby, the value of the first shake correction target value immediately after the shooting instruction (immediately after the start of still image exposure) is made the same as the value of the second shake correction target value immediately before the shooting instruction (immediately before the start of still image exposure). Thereby, continuity is given to the first and second shake correction target values before and after the shooting instruction.

[0042] In step S408, the shake correction target value is switched from the second shake correction target value to the first shake correction target value by the switching means 17. Then, the control means 12a causes the shake correction means 14 to start shooting shake correction based on the first shake correction target value.

[0043] In step S409, still image exposure is started.

[0044] In step S410, when the still image exposure is completed, the process proceeds to step S411; when it is not completed, step S410 is looped and waited.

[0045] In step S411, when there is a possibility that the first shake correction target value of the first signal processing means 16a overflows, the process proceeds to step S412. Otherwise, the process returns to step S405, and the control means 12a causes the shake correction means 14 to perform aiming shake correction based on the second shake correction target value.

[0046] In step S412, the overflow prevention means 18 subtracts (or adds) a constant value from the value of the first shake correction target value of the first signal processing means 16a. Thereby, overflow is prevented, and the process returns to step S405 to cause the shake correction means 14 to perform aiming shake correction based on the second shake correction target value.

[0047] As described above, in this embodiment, in step S403, the first and second signal processing means 16a and 16b are activated simultaneously to stabilize the first and second shake correction target values. Thereby, when starting still image exposure in step S409, stable shake correction with few low-frequency noise components can be performed.

[0048] Note that although overflow is prevented by subtracting (or adding) a constant value from the value of the first shake correction target value in step S412, it is not limited to such a method. For example, by configuring the integrator with an IIR filter and setting the history value in the IIR filter to zero once when overflow is predicted, the same effect as waveform 33 is produced. (Second Embodiment) FIG. 5 shows another example of preventing overflow. The same parts as those in FIG. 3 in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

[0049] In FIG. 5, waveform 53 is a waveform obtained by converting waveform 31 into an angular signal by the first signal processing means 16a. The difference between waveform 53 in FIG. 5 and waveform 33 in FIG. 3 is that during aiming, waveform 53a has a reduced integration gain to make arithmetic overflow less likely to occur. Also, at the start of shooting, after returning to waveform 53a as the center, the integration gain is set appropriately. Thereby, overflow is prevented and high-precision blur correction is possible during shooting.

[0050] In the second embodiment, the overflow prevention means 18 controls the integration gain of the first signal processing means 16a.

[0051] The waveform 34 indicates the shake correction target value along the shooting sequence of the camera 11. In the aiming sections of the sections 34a and 34c, the second shake correction target value of the waveform 32 is incorporated, and in the shooting section of the section 54b, the waveform 53b of the first shake correction target value at the same timing in the waveform 53 is incorporated. The shake correction means 14 is driven by these shake correction target values.

[0052] FIG. 6 is a control flow of the first and second signal processing means 16a and 16b by the camera CPU (control means) 12a in this embodiment, and this flow starts when the main power of the camera 11 is turned on or aiming starts.

[0053] Note that the same steps as those in FIG. 4 in the first embodiment are denoted by the same step numbers.

[0054] In step S401, the shake detection means 15 is activated.

[0055] In step S402, step S402 is looped and waited until the shake detection signal from the shake detection means 15 stabilizes (for example, 0.1 second).

[0056] In step S601, the integration gain of the first signal processing means 16a is decreased to about 1 / 5 of the standard value, for example.

[0057] In step S403, the control means 12a activates the first and second signal processing means 16a and 16b, and starts an operation to convert the shake detection signal from the shake detection means 15 into the first and second shake correction target values in the first and second signal processing means 16a and 16b.

[0058] As in steps S401 to S403, the first and second signal processing means 16a and 16b are activated after a predetermined time from the activation of the shake detection means 15. Therefore, the initial noise included in the shake detection means 15 is not input to the first and second signal processing means 16a and 16b, and the occurrence of fluctuations in the signal processing means 16 due to the initial noise of the shake detection means 15 is suppressed.

[0059] In step S404, step S404 is looped and waited until the angular signals of the first and second signal processing means 16a and 16b are stabilized (for example, for 0.5 seconds).

[0060] In step S405, the control means 12a causes the shake correction means 14 to start aiming shake correction based on the second shake correction target value.

[0061] In step S406, when an instruction to start shooting (start exposure) is given, the process proceeds to step S407; otherwise, the process returns to step S405 to continue shake correction.

[0062] In step S407, the control means 12a adds (or subtracts) a constant value to the first shake correction target value. Thereby, the value immediately after the shooting instruction in the first shake correction target value is made the same as the value immediately before the shooting instruction in the second shake correction target value. Thereby, continuity is given to the first and second shake correction target values before and after the shooting instruction.

[0063] In step S602, the integral gain of the first signal processing means 16a is restored. For example, when the integral gain is set to 1 / 5 in step S601, the integral gain is multiplied by 5 to make it the standard value.

[0064] In step S408, the control means 12a causes the shake correction means 14 to start shooting shake correction based on the first shake correction target value.

[0065] In step S409, still image exposure is started.

[0066] In step S410, when the still image exposure is completed, the process proceeds to step S603; when it is not completed, step S410 is looped and waited.

[0067] In step S603, similar to step S601, the integration gain of the first signal processing means 16a is decreased to about 1 / 5 of the standard value, for example. Then, returning to step S405, the control means 12a causes the shake correction means 14 to perform aiming shake correction based on the second blur correction target value.

[0068] In this way, the overflow prevention means 18 can prevent overflow by making the integration gain of the first signal processing means 16a during aiming smaller than the integration gain of the first signal processing means 16a during shooting. (Third Embodiment) FIG. 7 shows a cross-section of a camera (imaging system) 11 composed of a camera body (imaging device) 11a and an interchangeable lens (lens device) 11b detachably attached to the camera body 11a, and a simple control block diagram of the anti-shake system.

[0069] A camera CPU 12a provided in the camera body 11a controls the shooting operation and the anti-shake system operation in the camera 11 in response to a shooting instruction operation from a photographer.

[0070] A subject light beam along the optical axis 10 enters an image sensor 14a, which is an imaging means, through a photographing optical system 13 provided in the interchangeable lens 11b. The image sensor 14a outputs a signal in response to the incident subject light beam.

[0071] Reference numeral 15 denotes an angular velocity meter which is a first shake detection means corresponding to the first signal processing means 16a, and detects a shake detection signal (shake angular velocity) indicated by an arrow 15a applied to the camera 11. The signal of the first shake detection means 15 is converted by the first signal processing means 16a which outputs a first shake correction target value into a shake correction target value suitable for shake correction during shooting (during still image exposure).

[0072] The first shake correction target value is input to the driving means 14b when a shooting instruction is given from the photographer. The driving means 14b moves the imaging element 14a in the direction of arrow 14c based on the first shake correction target value. Thereby, shake correction in the direction along the imaging plane is performed. In this way, the imaging element 14a and the driving means 14b constitute the first shake correction means 14.

[0073] Note that the first shake detection means 15 also detects a shake detection signal (shake angular velocity) in a direction different from that of arrow 15a, and the first signal processing means 16a appropriately generates a blur correction target value for that signal. Then, the driving means 14b moves the imaging element 14a in a suitable direction according to the blur correction target value to perform shake correction in that direction.

[0074] The overflow prevention means 18 prevents an arithmetic overflow of the first signal processing means 16a.

[0075] The lens CPU 12b provided in the interchangeable lens 11b controls the focusing operation and the anti-shake system operation in the lens 11b in response to the operation of the camera 11a by the photographer.

[0076] 72 is an angular velocity meter which is a second shake detection means corresponding to the second signal processing means 16b, and detects a shake detection signal (shake angular velocity) indicated by the arrow 72a applied to the camera 11. The signal of the second shake detection means 72 is converted into a shake correction target value suitable for shake correction during aiming (the period when aiming at the subject for still image exposure preparation) by the second signal processing means 16b which outputs the second shake correction target value.

[0077] The second blur correction target value is input to the driving means 71b when an aiming instruction is given from the photographer. The driving means 71b performs shake correction by moving the shake correction lens 71a in the direction of arrow 71c based on the second shake correction target value. In this way, the shake correction lens 71a and the driving means 71b constitute the second shake correction means 71.

[0078] Incidentally, the second shake detection means 72 also detects a shake detection signal (shake angular velocity) in a direction different from that of the arrow 72a, and the second signal processing means 16b appropriately generates a shake correction target value for that signal. Then, the driving means 71b performs shake correction in that direction by moving the shake correction lens 71a in an appropriate direction according to the shake correction target value.

[0079] The camera CPU 12a and the lens CPU 12b communicate with each other and control the driving timings of the first and second shake detection means 15, 72, the first and second signal processing means 16a, 16b, and the first and second shake correction means 14, 71.

[0080] FIG. 8 is a control flow of the first and second signal processing means 16a, 16b by the camera CPU 12a and the lens CPU 12b in this embodiment, and this flow starts when the main power of the camera 11 is turned on or aiming starts.

[0081] Incidentally, the same steps as those in FIG. 4 of the first embodiment and FIG. 6 of the second embodiment are represented by the same step numbers.

[0082] In step S401, the first and second shake detection means 15, 72 are activated.

[0083] In step S402, step S402 is cycled and waited until the shake detection signals from the first and second shake detection means 15, 72 become stable (for example, 0.1 second).

[0084] In step S601, the integration gain of the first signal processing means 16a is reduced to about 1 / 5 of the standard value, for example.

[0085] In step S403, the camera CPU 12a and the lens CPU 12b activate the first and second signal processing means 16a and 16b, respectively. Then, the camera CPU 12a and the lens CPU 12b cause the first and second signal processing means 16a and 16b to start an operation of converting the shake detection signals from the first and second shake detection means 15 and 72 into the first and second shake correction target values.

[0086] As in steps S401 to S403, the first and second signal processing means 16a and 16b are activated after a predetermined time from the activation of the first and second shake detection means 15 and 72. Therefore, the initial noise included in the first shake detection means 15 is not input to the first and second signal processing means 16a and 16b, and fluctuations in the first and second signal processing means 16a and 16b due to the initial noise of the first shake detection means 15 are suppressed.

[0087] In step S404, step S404 is looped and waited until the angular signals of the first and second signal processing means 16a and 16b become stable (for example, 0.5 seconds).

[0088] In step S801, the lens CPU 12b drives the second shake correction means 71 based on the second shake correction target value, and starts shake correction for aiming on the second shake correction means 71.

[0089] In step S406, when an instruction to start shooting (start exposure) is given, the process proceeds to step S407, and when not, the process returns to step S801 to continue shake correction.

[0090] In step S407, the camera CPU 12a and the lens CPU 12b add (or subtract) a constant value to the first shake correction target value. Thereby, the value immediately after the shooting instruction in the first shake correction target value is made the same as the value immediately before the shooting instruction in the second shake correction target value. Thereby, continuity is given to the first and second shake correction target values before and after the shooting instruction.

[0091] In step S602, the integration gain of the first signal processing means 16a is restored. For example, when the integration gain is set to 1 / 5 in step S601, the integration gain is multiplied by 5 to make it the standard value.

[0092] In step S802, the lens CPU 12b stops driving the second shake correction means 71.

[0093] In step S803, the camera CPU 12a starts shooting shake correction by the first shake correction means 14 based on the first shake correction target value.

[0094] In step S409, still image exposure is started.

[0095] In step S410, when the still image exposure is completed, the process proceeds to step S804, and when it is not completed, the process loops in step S410 and waits.

[0096] In step S804, the camera CPU 12a stops driving the first shake correction means 14.

[0097] In step S603, similar to step S601, the integration gain of the first signal processing means 16a is reduced to about 1 / 5 of the standard value, for example. Then, the process returns to step S801, and the lens CPU 12b performs aiming shake correction by the second shake correction means 71 based on the second shake correction target value.

[0098] As described above, in this embodiment, an anti-shake system is provided in each of the interchangeable lens 11b and the camera body 11b. During aiming, shake correction is performed by the interchangeable lens 11b, and in parallel, the camera body 11a calculates the first shake correction target value for shooting. Thus, stable shake correction can be performed on the camera body 11a side at the start of shooting. (Other embodiments) The present invention can also be realized by supplying a computer program that realizes one or more functions of the above 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 (for example, ASIC) that realizes one or more functions.

[0099] According to each embodiment, it is possible to provide an imaging device, a control method, a program, and a storage medium capable of performing stable shake correction with few noise components included in the shake detection means when performing still image exposure.

[0100] As described above, the preferred embodiments of the present invention have been described, but the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist thereof.

Explanation of Reference Numerals

[0101] 16 Signal processing means 12a Control means 18 Overflow prevention means

Claims

1. A shake detection means for detecting a shake detection signal related to shake applied to the imaging device, obtaining the shake detection signal, and a signal processing means for outputting a shake correction target value using the shake detection signal; Control means for controlling shake correction in a direction along the imaging surface by controlling the movement of at least one of the imaging element and some of the lenses included in the imaging optical system based on the shake correction target value; Overflow prevention means for preventing an arithmetic overflow of the shake correction target value, and having: The signal processing means includes first signal processing means for outputting a first shake correction target value, and second signal processing means having frequency characteristics different from those of the first signal processing means, and outputting a second shake correction target value in parallel with the output of the first shake correction target value by the first signal processing means; The first signal processing means has first integration means for integrating the shake detection signal; The control means is: When aiming at a subject in preparation for still image exposure, controlling the shake correction based on the second shake correction target value; When performing the still image exposure, controlling the shake correction based on the first shake correction target value; The overflow prevention means performs a process of preventing the arithmetic overflow by rewriting the output of the first integration means during a period in which the control means controls the shake correction based on the second shake correction target value. A shake correction control device characterized by that.

2. The overflow prevention means rewrites the first integration means by subtracting or adding a constant signal to the first shake correction target value when the first shake correction target value exceeds a predetermined value, and the first shake correction target value The shake correction control device according to claim 1, characterized in that an arithmetic overflow of is prevented.

3. The control means starts the first and second signal processing means after a predetermined time from the start of the shake detection means. The shake correction control device according to claim 1 or 2, characterized by that.

4. The control means adds or subtracts a constant value from the first shake correction target value, so that the value immediately after the start of the still image exposure in the first shake correction target value is the same as that immediately before the start of the still image exposure in the second shake correction target value. The shake correction control device according to any one of claims 1 to 3, characterized in that they are aligned.

5. The shake correction control device according to any one of claims 1 to 4, wherein the control means activates the first and second signal processing means simultaneously.

6. The shake correction control device according to any one of claims 1 to 5, wherein the time constant of the first signal processing means is larger than the time constant of the second signal processing means.

7. The overflow prevention means reduces the integration gain of the first signal processing means when aiming at a subject for still image exposure preparation, compared to the integration gain of the first signal processing means when performing still image exposure. The shake correction control device according to any one of claims 1 to 6, characterized in that.

8. The shake detection means is composed of a first shake detection means corresponding to the first signal processing means and a second shake detection means corresponding to the second signal processing means. The first shake detection means is provided in an imaging device including the imaging element. The shake correction control device according to any one of claims 1 to 7, wherein the second shake detection means is provided in a lens device including the imaging optical system.

9. The control means A first shake correction means provided in the imaging device for performing shake correction in a direction along the imaging surface by moving the imaging element. The shake correction control device according to claim 8, characterized in that the shake correction is controlled by a second shake correction means provided in the lens device for performing shake correction in a direction along the imaging surface by moving a part of the lenses.

10. An imaging device comprising the shake correction control device according to any one of claims 1 to 9, And the imaging element for imaging light from the imaging optical system.

11. Comprising a first shake correction means for performing shake correction in a direction along the imaging surface by moving the imaging element. The imaging device according to claim 10, characterized in that the control means controls the shake correction by controlling at least the first shake correction means.

12. A lens device detachable from an imaging device, Comprising the shake correction control device according to any one of claims 1 to 9, And the imaging optical system.

13. Comprising a second shake correction means for performing shake correction in a direction along the imaging surface by moving a part of the lenses. The lens device according to claim 12, wherein the control means controls the shake correction by controlling at least the second shake correction means.

14. A shake correction control device according to any one of claims 1 to 9, the imaging optical system, the imaging element that images light from the imaging optical system, and shake correction means for moving at least one of the imaging element and a part of the lenses included in the imaging optical system, and the control means controls the shake correction by controlling the movement of at least one of the imaging element and the part of the lenses by the shake correction means. An imaging system characterized by that.

15. As the shake correction means, first shake correction means for performing shake correction in a direction along the imaging plane by moving the imaging element, and second shake correction means for performing shake correction in a direction along the imaging plane by moving the part of the lenses. The imaging system according to claim 14, comprising:

16. A control method for a shake correction control device that controls shake correction in a direction along an imaging plane by moving at least one of an imaging element and a part of the lenses included in an imaging optical system, a shake acquisition step of acquiring a shake detection signal related to shake applied to the imaging device, a signal processing step of outputting a shake correction target value using the shake detection signal, an overflow prevention step of preventing an arithmetic overflow of the shake correction target value, and a control step of controlling the shake correction based on the shake correction target value, and the signal processing step performs in parallel a first signal processing step of outputting a first shake correction target value and a second signal processing step having frequency characteristics different from those of the first signal processing step and outputting a second shake correction target value, the first signal processing step has a first integration step of integrating the shake detection signal, the control step is when aiming at a subject for preparation of still image exposure, controls the shake correction based on the second shake correction target value, when performing the still image exposure, controls the shake correction based on the first shake correction target value, The overflow prevention step performs a process of preventing the arithmetic overflow by rewriting the output in the first integration step during a period in which the control step controls the shake correction based on the second shake correction target value. A control method characterized by that.

17. A computer-readable storage medium storing a computer program that causes a computer of a shake correction control device to execute a process according to a control method of shake correction that performs shake correction in a direction along an imaging surface by moving at least one of an imaging element and some of the lenses included in an imaging optical system, The control method includes: A shake acquisition step of acquiring a shake detection signal related to the shake applied to the imaging device; A signal processing step of outputting a shake correction target value using the shake detection signal; An overflow prevention step of preventing an arithmetic overflow of the shake correction target value; A control step of controlling the shake correction based on the shake correction target value, and The signal processing step performs in parallel a first signal processing step of outputting a first shake correction target value and a second signal processing step having frequency characteristics different from those of the first signal processing step and outputting a second shake correction target value, The first signal processing step includes a first integration step of integrating the shake detection signal, The control step includes: When aiming at a subject in preparation for still image exposure, controlling the shake correction based on the second shake correction target value, When performing the still image exposure, controlling the shake correction based on the first shake correction target value, The overflow prevention step performs a process of preventing the arithmetic overflow by rewriting the output in the first integration step during a period in which the control step controls the shake correction based on the second shake correction target value. A storage medium characterized by that.

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