JP6053429B2 - Imaging device and aperture control method of imaging device - Google Patents

Description

  The present invention relates to an imaging apparatus having an aperture blade that is driven in an opening direction or a narrowing direction by an aperture driving unit having an actuator, and an aperture control method for the imaging apparatus.

  In a camera that displays or records the distance to the subject and the size of the subject, a technology for driving the lens based on the number of pulses obtained by subtracting the number of pulses necessary to correct backlash from the predetermined number of lens extension pulses is known. (See, for example, paragraphs 0021 and 0022 of Patent Document 1).

  In addition, when the amount of backlash is greater than a predetermined value, regardless of which side of the target position the focus lens is, the technology that cancels backlash by controlling the focus lens to always move from the same direction to the target position. Is known (see, for example, paragraph 0039 of the patent document).

JP-A-5-297437 JP 2011-149970 A

  When the lens driving technique disclosed in Patent Document 1 described above is applied to aperture control, the value of backlash differs depending on the aperture position. Therefore, a target aperture drive amount is calculated, and the aperture drive amount is calculated from the aperture drive amount. A two-stage process of correcting the backlash and driving the diaphragm to a predetermined position is required. In addition to data representing the relationship between the lens driving amount and the aperture value, it is necessary to store backlash data corresponding to each aperture value.

  Further, in the lens driving technique disclosed in Patent Document 2 described above, since the focus lens is always moved from the same direction to the target position, it takes time to drive the lens. When this technique is applied to aperture control and moving image shooting is performed, it is difficult to perform smooth aperture control.

  The present invention has been made in view of such circumstances, and an imaging apparatus and an aperture control method for an imaging apparatus that can quickly remove the influence of backlash that occurs during aperture driving and perform smooth aperture control. The purpose is to provide.

Imaging device according to the first invention for achieving the above object, a diaphragm blade for limiting the quantity of light, a diaphragm drive section for driving the upper Symbol diaphragm blade opening direction, or narrowing direction, said at a predetermined open aperture First data representing the relationship between the driving amount of the diaphragm blade and the effective aperture value when driving the diaphragm blade in the narrowing-down direction with the driving amount of the diaphragm blade as a reference, and when driving the diaphragm blade in the opening direction A memory for storing second data representing the relationship between the driving amount of the diaphragm blades and the effective diaphragm value, and when driving the diaphragm blades in the narrowing direction, the driving amount of the diaphragm blades with reference to the first data When the diaphragm blades are driven in the opening direction, a drive control unit that controls the drive amount of the diaphragm blades with reference to the second data, and an aperture value corresponding to the position of the diaphragm blades are detected. Aperture A lens unit having a detecting section, and the goal aperture and a camera body to be transmitted to the drive control unit, the drive control unit, the current aperture value and detected by the aperture value detecting unit When the driving direction is determined from the target aperture value and the driving direction is reversed to drive the aperture driving unit, the effective value corresponding to the current aperture value is referred to by referring to the first data and the second data. Driving amount of the diaphragm blades when driving the diaphragm blades in the aperture direction at the aperture value, and driving of the diaphragm blades when driving the aperture blades in the opening direction at the effective aperture value corresponding to the current aperture value Cancel the backlash by the difference between the amount by driving the diaphragm driving unit, in the above backlash canceling operation, backlash canceling operation to be detected before starting the above current The corresponding data transmitted to the camera body to Values.

The imaging apparatus according to a second invention is the imaging device according to the first invention, wherein the drive control unit uses the first data or the second data to be referred to corresponding to the determined drive direction, and the target aperture value. The driving amount of the diaphragm blades is controlled after the backlash canceling operation based on the driving amount located in the driving direction among the two driving amounts of the diaphragm blades corresponding to.

According to a third aspect of the present invention, there is provided the imaging apparatus according to the second aspect, wherein the diaphragm driving unit includes an actuator that drives the diaphragm blades, and in the driving region of the diaphragm driving unit for canceling the backlash. The actuator is driven at a first speed, and the actuator is driven at a second driving speed that is higher than the first driving speed in the driving area of the actuator where the diaphragm blades move.

  In the image pickup apparatus according to a fourth aspect of the present invention, in the first aspect of the present invention, the moving speed of the aperture driving unit is slower during moving image shooting than during still image shooting.

According to a fifth aspect of the present invention, there is provided a diaphragm control method for an imaging apparatus, comprising: a lens unit having a diaphragm driving unit that transmits a driving force to a diaphragm blade that restricts the amount of light ; In an aperture control method of an imaging apparatus having a camera body that transmits a standard aperture value to the lens unit, when the aperture blade is driven in the aperture direction based on the drive amount of the aperture blade at a predetermined open aperture value First data representing the relationship between the driving amount of the diaphragm blades and the effective diaphragm value, or second data representing the relationship between the driving amount of the diaphragm blades and the effective diaphragm value when driving the diaphragm blades in the open direction opening a reading step, when the lens unit is to drive the diaphragm blades in the narrowing direction with reference to the first data by controlling the driving amount of the diaphragm blades, the diaphragm blades read from A drive control step for controlling the drive amount of the aperture blade with reference to the second data when driving in the direction, the drive control step is driven from the current aperture value and the target aperture value When the direction is discriminated and the driving direction is reversed to drive the aperture driving unit, the aperture blade at the effective aperture value corresponding to the current aperture value is referred to by referring to the first data and the second data. The aperture is the difference between the drive amount of the aperture blade when driving in the aperture direction and the drive amount of the aperture blade when driving the aperture blade in the open direction at the effective aperture value corresponding to the current aperture value. to cancel the backlash by driving the driving unit, in the above backlash canceling operation, said data corresponding to the front of the current aperture value to start the backlash canceling operation And transmits it to the camera main body.

  According to the present invention, it is possible to provide an imaging apparatus and an aperture control method for an imaging apparatus that can quickly remove the influence of backlash that occurs during aperture driving and perform smooth aperture control.

It is a block diagram which shows the structure of the camera which concerns on one Embodiment of this invention. 1 is a block diagram mainly showing an electrical configuration of a camera according to an embodiment of the present invention. It is a figure which shows the aperture mechanism of the camera which concerns on one Embodiment of this invention. It is a figure which shows the aperture mechanism of the camera which concerns on one Embodiment of this invention. It is a figure explaining the reason for the occurrence of backlash in the aperture mechanism of a camera according to an embodiment of the present invention. It is a figure which shows the generation | occurrence | production location of a backlash in the camera which concerns on one Embodiment of this invention. It is a figure which shows the pulse map in the aperture_diaphragm | restriction of the camera which concerns on one Embodiment of this invention. It is a figure which shows the table for aperture adjustment in the camera which concerns on one Embodiment of this invention. It is a figure which shows the table which interpolated the adjustment value for aperture adjustment in the camera which concerns on one Embodiment of this invention. It is a figure explaining the meaning of the interpolation type performed when performing aperture adjustment in the camera concerning one embodiment of the present invention. 6 is a graph showing driving in the direction of aperture → opening and driving in the direction of opening → stopping in the camera according to the embodiment of the present invention. It is a flowchart which shows the operation | movement of the aperture target position drive of the camera which concerns on one Embodiment of this invention. 6 is a flowchart showing operations of target AV correction and driving direction determination of the camera according to the embodiment of the present invention. 6 is a flowchart showing operations of target AV correction and driving direction determination of the camera according to the embodiment of the present invention. It is a flowchart which shows operation | movement of search from the reference table of the camera which concerns on one Embodiment of this invention. It is a flowchart which shows the operation | movement of the forward drive of the camera which concerns on one Embodiment of this invention. It is a flowchart which shows the operation | movement of a hiss removal (calculation) drive of the camera which concerns on one Embodiment of this invention. 6 is a flowchart showing an operation of driving a diaphragm of a camera according to an embodiment of the present invention. FIG. 6 is a diagram for explaining a driving state when a reverse rotation of the aperture drive occurs and when it does not occur in the camera according to the embodiment of the present invention. FIG. 6 is a diagram for explaining a driving state when a reverse rotation of the aperture drive occurs and when it does not occur in the camera according to the embodiment of the present invention.

  Hereinafter, a preferred embodiment will be described using a camera to which the present invention is applied according to the drawings. A camera according to a preferred embodiment of the present invention is a digital camera, and an aperture device driven by an aperture drive mechanism is provided in a lens barrel. First data indicating the relationship between the driving amount of the diaphragm blade and the effective diaphragm value when the diaphragm blade of the diaphragm device is driven in the narrowing direction (see, for example, FIG. 9A), and the diaphragm blade is driven in the opening direction. The second data indicating the relationship between the driving amount of the diaphragm blades and the effective aperture value at that time (for example, see FIG. 9B). Then, the driving amount is controlled using the first or second data according to the driving direction of the diaphragm blades.

  In the present embodiment, when the driving direction is reversed between the narrowing direction and the opening direction, the driving amount of the diaphragm blades in the narrowing direction at the predetermined effective diaphragm value and the opening direction at the predetermined effective diaphragm value. The backlash is canceled using the difference in the driving amount of the diaphragm blades.

  Hereinafter, a preferred embodiment using a camera to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of a camera according to an embodiment of the present invention, and FIG. 2 is a block diagram illustrating an electrical configuration of the camera. This camera includes an interchangeable lens 100 and a camera body 200. However, it goes without saying that the lens barrel and the camera body may be integrated.

  The interchangeable lens 100 includes a lens 11a, a focus lens 11b, and a lens 11c (referred to as the taking lens 11 when these lenses are collectively referred to). A subject image is formed by the photographing lens 11. Among these, the focus lens 11 b is a focus adjusting lens, and can be moved in the optical axis direction by the focus lens driving mechanism 25. The focus lens drive mechanism 25 includes a focus lens actuator and a focus lens drive circuit. As the focus lens actuator, a stepping motor or a voice coil motor (VCM) is used.

  Further, when the focus lens 11b reaches the reference position, the focus lens reference position detection unit 27 outputs a detection signal to the CPU 41 that is a control unit. A photo interrupter (PI) is used for the reference position detection. In the present embodiment, when the reference position is detected, the position of the focus lens 11b is detected based on the number of pulses applied to an actuator (stepping motor, pulse motor, etc.) for the focus lens based on the position. Do it.

  A diaphragm 13 is disposed between the lenses 11a and 11c. The aperture of the aperture 13 is changed by the aperture driving mechanism 21 to change the amount of subject light passing through the photographing lens 11. The diaphragm 13 has diaphragm blades 91 (see FIGS. 4 and 5) that limit the amount of light.

  The aperture drive mechanism 21 includes an aperture actuator, an aperture driver circuit, and the like. As an actuator, a stepping motor is used, and fine control is performed by microstep drive. Of course, the diaphragm 13 may be arranged other than between the lenses 11a and 11b. The aperture drive mechanism 21 functions as an aperture drive unit that drives the aperture blades in the opening direction or the aperture direction. The diaphragm 13 and the diaphragm drive mechanism 21 will be described later with reference to FIGS.

  The diaphragm reference position detection unit 23 outputs a detection signal to the CPU 41 when the aperture diameter of the diaphragm reaches the reference position. The aperture position is acquired by the aperture reference position detection unit 23 and managed by relative position detection. The relative position is detected by the number of pulses applied to the stepping motor, and the reference position is detected by a photo interrupter (PI). The aperture value represented by the number of applied pulses from the reference position (also referred to as the number of steps) is referred to as absolute Pls, and the aperture value representing the relative distance determined by the two aperture positions as the applied pulse number is referred to as relative Pls. The mechanism of the aperture reference position detection unit 23 will be described later with reference to FIG.

  An MF ring 51 for manual focus and a ZM ring 53 for focus adjustment are disposed on the outer periphery of the interchangeable lens 100. The MF ring 51 and the ZM ring 53 are rotatable on the outer periphery of the interchangeable lens 100. Manual focus is performed according to the rotation of the MF ring 51, and zooming is performed according to the rotation of the ZM ring 53.

  The MF position detection unit 35 detects the rotation direction and the rotation amount of the MF ring 51. When the MF ring 51 is rotated, a light shielding blade that rotates in conjunction with the rotation of the MF ring 51 and a photo interrupter (PI) provided within the rotation range of the light shielding blade are provided in the interchangeable lens 100. Is provided. Based on the output of the photo interrupter (PI), the rotation direction and the rotation amount of the MF ring 51 are detected. Manual focus is executed according to the count value by this PI.

  The CPU 41 as a control unit controls the interchangeable lens 100 according to a control command from the camera body 200 according to a program stored in the storage unit 37. The CPU 41 receives detection signals from the aperture reference position detection unit 23, the focus lens reference position detection unit 27, and the MF position detection unit 35, and outputs control signals to the focus lens drive mechanism 25 and the aperture drive mechanism 21.

  The storage unit 37 includes a rewritable nonvolatile memory such as the flash memory 37, and stores various information such as optical data of the interchangeable lens, various adjustment values, and the like in addition to the above-described program for the CPU 41. Further, as will be described later, the first data indicating the relationship between the driving amount of the diaphragm blade and the effective diaphragm value when the diaphragm blade of the diaphragm device is driven in the narrowing direction (see, for example, FIG. 9A), the diaphragm Second data indicating the relationship between the driving amount of the diaphragm blades and the effective diaphragm value when driving the blades in the opening direction is stored (see, for example, FIG. 9B).

  The aforementioned CPU 41 controls the driving amount of the diaphragm blade 91 with reference to the first data described above when driving the diaphragm blade 91 in the narrowing direction, and the above-described second operation when driving the diaphragm blade 91 in the open direction. It functions as a drive control unit that controls the drive amount of the diaphragm blade 91 with reference to the data (see S33 to S37 in FIG. 14 described later). The CPU 41 refers to the first data and the second data when reversing the driving direction to drive the diaphragm driving unit, and refers to the first blade and the second data when driving the diaphragm blade at a predetermined effective aperture value in the narrowing direction. Backlash is canceled by driving the aperture drive unit by the difference between the drive amount and the drive amount of the aperture blade when the aperture blade is driven in the opening direction at the predetermined effective aperture value (S41 in FIGS. 11 and 14). To S49).

  An image sensor 201 is disposed in the camera body 200. The image sensor 201 is disposed in the vicinity of the imaging position of the photographic lens 11, photoelectrically converts a subject image formed on the photographic lens 11, and outputs image data. A control CPU is also provided in the camera body 200 and communicates with the CPU 41 in the interchangeable lens 100.

  Next, the details of the electrical configuration will be described with reference to FIG. As described above, the CPU 41 can communicate with the camera body 200. The CPU 41 is connected to a motor driver 71, and the motor driver 71 drives the LDPI 69, LDMT 73, AVMT 75, and AVPI 77.

  The LDMT 73 which is a part of the focus lens drive function 25 is a lens drive motor and a focus actuator. The AVMT 75 which is a part of the aperture drive mechanism 21 is an aperture drive motor (aperture actuator). The LDPI 69 is a PI for detecting a reference position when driving the lens. AVPI 77, which is a part of the aperture reference position detection 23, is a PI for detecting a reference value during aperture driving.

  The output of the LDPI 69 is connected to the LDPI binarization circuit 67. The LDPI 69 and the LDPI binarization circuit 67 correspond to the focus lens reference position detection unit 27 described above. The output of AVPI 77 is connected to AVPI binarization circuit 79. The AVPI 77 and the AVPI binarization circuit 79 correspond to the aperture reference position detection unit 23 described above.

  The MFPI driver 65 is a driver of the MFPI 63 for detecting the rotation of the MF ring 51. The MFPI 63 is provided at two locations along the rotation direction of the light shielding blade that rotates in conjunction with the MF ring 51. The output of the MFPI 63 is connected to the MFPI binarization circuit 61 and is binarized by the MFPI binarization circuit 61. The MFPI binarization circuit 61, the MFPI 63, and the MFPI driver 65 correspond to the MF position detection unit 35 described above.

  Next, the configuration of the diaphragm 13, the diaphragm drive mechanism 21, and the diaphragm reference position detector 23 will be described with reference to FIGS. FIG. 3A is a plan view of the diaphragm mechanism with the diaphragm blades 91 removed, and FIG. 3B is a perspective view in the state of FIG. 4A is a perspective view showing the structure of the diaphragm reference position detection unit 23, and FIG. 4B is a plan view of the diaphragm mechanism in a state where the diaphragm blades 91 are mounted. FIG. 4C is a plan view of the diaphragm plate 95 and the diaphragm holding plate 93, and FIG. 4D is a rear view of the state of FIG. 5A is an enlarged view of the diaphragm blade 91, FIG. 5B is an enlarged view of the cam hole 91a and the pin 95b of the diaphragm blade 91, and FIG. 5C is a motor pinion 83. FIG. 6 is an enlarged view of a meshing portion between the connecting portion gear 85 and the connecting portion gear 85.

  In FIG. 3, a diaphragm motor 81 (corresponding to AVMT 75 in FIG. 2) is provided on a fixed member of the diaphragm unit, and a motor pinion gear 83 at the center of rotation is rotated. The connecting portion gear 85 meshes with the motor pinion gear 83. As shown in FIG. 4D, the connecting portion gear 85 is formed integrally with the diaphragm plate 95.

  Further, as shown in FIG. 4A, a light shielding plate 85a extends on one end side of the connecting portion gear 85, and a reference position detection PI 87 (FIG. 2) is placed in the rotation path of the light shielding plate 85a. Equivalent to AVPI77). As will be described later, when the effective aperture value of the diaphragm blade 91 is determined according to the rotation amount of the connecting portion gear 85 and the connecting portion gear 85 reaches the reference position, the reference position detecting PI 87 outputs a detection signal. This detection is performed by the AVPI 77 and the AVPI binarization circuit 79 described above.

  As shown in FIG. 4B, the diaphragm blade 91 is pivotally supported by a pin 91 planted on the fixed plate 92. Each of the plurality of aperture blades 91 is provided with a cam hole 91a, and a pin 95b is inserted into the cam hole 91a. The pin 95b is planted on the diaphragm plate 95. Since the diaphragm plate 95 is configured integrally with the connecting gear 85 described above, when the diaphragm plate 95 is rotated, the pin 95b is also rotated, and the diaphragm blade 91 is also rotated with this rotation. The opening amount of 13 changes. Reference numeral 93 denotes an aperture stop plate.

  Further, as shown in FIG. 3, a closing spring 89 is provided between the projection 95a of the diaphragm plate 95 and the fixing member 92 of the diaphragm unit. Due to the spring force of the bias spring 89, the diaphragm plate 95 is always given a biasing force in one direction.

  The reason for the occurrence of backlash will be described with reference to FIG. In a normal motor gear, the backlash component is determined by so-called play (play required for movement). That is, as shown in FIG. 5C, the teeth of the gear are not in close contact with each other, and a slight gap D (backlash, play) is provided. Due to this gap D, backlash occurs.

  In the case of an aperture, there is a backlash component of the aperture blade in addition to the motor gear. As shown in FIG. 5A, a pin 95 b is inserted into the cam hole 91 a of the diaphragm blade 91. When driving in the direction of a small pressure angle (in the direction of arrow A in the figure), the amount of light change per step is small, and the pressure angle is small on the small aperture side (maximum aperture value side). For this reason, as shown in a region P in FIG. 6, backlash tends to occur on the forward and return paths on the small aperture side. Also, the amount of backlash is not constant and varies depending on the location.

  In the case of performing live view display or moving image shooting, backlash cancellation is performed while the user is observing. Even during this backlash canceling operation, the aperture value (AV value) must be transmitted to the camera body 200. When normal backlash cancellation is performed, the value transmitted to the camera body deviates from the instruction value from the camera body, and automatic exposure is not normally performed. Therefore, a cancel operation that is driven from one direction or is driven back by a large amount in front as in normal backlash cancellation cannot be performed in live view display or the like.

  Moreover, since the shape of the aperture blade 91 is complicated, the backlash amount differs for each product. Note that the backlash amount in this case is not the mechanical movement amount pulse (Pls) but the resultant aperture value (control AV value).

  As described above, when the diaphragm blades 91 are driven, the amount of backlash differs between when the diaphragm blades 91 are driven to the narrowing side and the open side. Even if the backlash amount is different, the above-described problem is prevented from occurring in this embodiment.

  Next, the diaphragm pulse map will be described with reference to FIG. In the present embodiment, the effective aperture value is the number of pulses (also referred to as the number of steps) of the aperture motor 81 (AVMT75) from the reference position detected by the aperture reference position detector 23 (AVPI77, reference position detection PI87). Find by counting. In FIG. 7A, the leftmost column indicates the position of the stop, and the right column indicates the number of pulses in the two-phase two-pulse system. Note that @ 1 / 16μ represents a unit of the drive pulse (Pls).

  In the example shown in FIG. 7A, the -12 pulse position is the mechanical end, the 0 pulse position is the reset position, the 8 pulse position is the PI position (detection position of the reference position detection PI 87), and the 20 pulse position is the aperture. The open position, the 116 pulse position is the minimum aperture position, the 130 pulse position is the control end position, and the 132 position is the mechanical end position. This positional relationship is shown in FIG. As can be seen from this figure, the position at which the output of the aperture reference position detector 23 (AVPI 77, reference position detection PI 87) switches from Hi to Low is the PI position, and 8 pulses (Pls) from the position to the mechanical end side. Is the reset position. With this reset position as a reference, the position of the aperture blade can be managed by the number of pulses (Pls) of the aperture motor 81 (AVMT75).

  Next, generation of an aperture adjustment value table will be described. As described with reference to FIG. 5, the aperture 13 has backlash. For this reason, the position of the aperture blade described with reference to FIG. 7 differs between the aperture direction and the open direction. Therefore, in this embodiment, in the manufacturing stage at the factory, pulses (Pls) are applied to the individual aperture units in the wide state and the tele state, and the effective aperture value with respect to the number of pulses (number of steps) at this time is measured. Then, a table is generated by calculating an effective aperture value in an intermediate state from this measured value. The adjusted aperture value obtained in this way is called a control aperture value.

  First, an aperture-aperture adjustment value table and an opening-opening adjustment value table as shown in FIG. This adjustment value table sets the photographic lens 11 in the wide state, and each time the pulse (Pls) of the aperture motor 81 (AVMT75) is applied from the full aperture side toward the minimum aperture side in this state, the number of steps at this time Measure the effective aperture value according to. Thereby, the data in the row direction of “aperture-aperture direction” in the wide state of FIG. 8A can be acquired. Subsequently, the effective aperture value corresponding to the number of steps is similarly measured from the minimum aperture side toward the open side, and the data in the row direction of “opening-opening direction” in FIG.

  When the adjustment value table in the wide state is generated, the photographing lens 11 is then set in the tele state, and similarly, the effective aperture values in “aperture-aperture direction” and “opening direction” are measured, and the adjustment value table in the tele state Is generated.

  In the table shown in FIG. 7A, the two-phase / two-pulse method is displayed in 1/16 μ steps. However, at the time of generating the adjustment value table, measurement is performed in steps of 1/8 μ step in order to drive in a one-phase / two-pulse method in which driving is stable. For this reason, it drives by a 1 phase-2 pulse system, performs an interpolation calculation using the measured effective value, and produces | generates an adjustment value table as shown to Fig.8 (a) in @ 1/16 micro step. The interpolation calculation may be linear approximation if the linearity is good, or another interpolation calculation formula may be used. In the example shown in FIG. 8A, the effective aperture value is measured for each step. However, if the linearity of the cam hole 91a of the aperture blade 91 is good, the measurement points may be reduced. In addition, the case where the rotation of the rotation axis of the stepping motor (pulse motor) is divided into 16 parts is controlled by @ 1 / 16μ steps, and the case where the rotation is divided into eight parts is controlled by @ 1 / 8μ steps. When driven by a two-phase, two-pulse method, which will be described later, it becomes possible to control in @ 1 / 16μ steps.

  When the adjustment value table shown in FIG. 8A is generated, an interpolated adjustment value table is calculated for each zoom encoder. That is, the table shown in FIG. 8 is an adjustment value at two focal lengths of the zoom lens in the wide state and the tele state, and an adjustment value at an intermediate focal length between wide and tele is calculated by an interpolation operation. Generate. That is, as shown in FIG. 8B, the “aperture-aperture” and “open-open” adjustment data are used to adjust the “aperture-stop-direction interpolation AV value” and the “open-open-direction interpolation AV value”. "Aperture-Aperture Interpolation AV Table" and "Open-Open Interpolation AV Table" are generated.

The interpolation calculation is performed according to the following equation (1).
Interpolation AV value = {(Tele instruction Step adjustment value−Wide instruction Step adjustment value) / (Tele instruction Step design value−Wide instruction Step design value)} * (Current ZM position instruction Step design value−Wide instruction Step design value) + Wide instruction Step adjustment value (1)

  Here, the Tele instruction Step adjustment value and the Wide instruction Step adjustment value correspond to A1-A2 in FIG. 10, the Tele instruction Step design value-Wide instruction Step design value corresponds to D1-D2, and the current ZM position instruction. Step design value-Wide instruction Step design value corresponds to D3-D2. The interpolated AV value to be obtained corresponds to A3.

In this interpolation formula (1), the adjustment value corresponding to the intermediate focal length is calculated by taking the ratio of the AV value between the wide of the design value, the adjustment value, and the telephoto. That is, in FIG. 10, the line A connects the adjustment values (see FIG. 8A), and the line D connects the design values (see FIG. 8C). In FIG.
ΔAV_Cal: ΔAV_Adj = ΔAV_Cal_Trg: ΔAV_Adj_Trg (2)
The adjustment value at the intermediate focal length (corresponding to the current ZM position instruction Step) is obtained by linear interpolation.

  FIG. 9 is an example of an adjustment table based on an adjustment value generated by obtaining an adjustment value (interpolated AV value) at an intermediate focal length (zoom encoder value) by the interpolation calculation as described above. That is, FIG. 9A shows the aperture → aperture direction adjustment value, which corresponds to first data representing the relationship between the driving amount of the aperture blade 91 and the effective aperture value when the aperture blade 91 is driven in the aperture direction. . FIG. 9B shows an opening → opening direction adjustment value, which corresponds to second data representing the relationship between the driving amount of the diaphragm blade and the effective diaphragm value when the diaphragm blade is driven in the opening direction. These first and second data are stored in the storage unit 37 after adjustment values are generated in a factory or the like.

  Next, an outline of aperture control will be described. In this embodiment, when controlling the aperture amount of the aperture, when the aperture is driven in the aperture direction, the aperture motor 81 according to the “aperture → aperture direction adjustment value” adjustment table shown in FIG. A pulse is applied to (AVMT75). Further, when the diaphragm is driven in the opening direction, a pulse is applied to the diaphragm motor 81 (AVMT 75) according to the adjustment table of “opening → opening direction adjustment value” shown in FIG. 9B. On the other hand, the drive direction may be reversed from the opening direction to the aperture direction or from the aperture direction to the aperture direction. Operations in these cases will be described with reference to FIG.

  A case where the driving direction is reversed from the aperture direction to the opening direction will be described with reference to FIG. In the example shown in FIG. 11 (a), the aperture is narrowed down in the aperture direction Pa along the aperture-aperture control AV value line P, and is currently at the aperture value P1. It is assumed that the target AV value Q1 is instructed from the camera body at this time. At this time, the CPU 41 compares the previous driving direction, the current AV value P1 and the target AV value Q1, and determines whether the driving is in the opening direction. In the example shown in FIG. 11A, since the target AV value Q1 is smaller than the current AV value P1, the aperture blade 91 is driven by the aperture motor 81 (AVMT75) in the opening direction.

  In this case, since driving in the opening direction is performed, Pls that matches the target AV value corresponding to the current focal length is referred to with reference to the “open → open AV interpolation table” (see FIG. 9B). Search and drive for the difference between the current Pls and the target Pls. Pls is currently transmitted to the camera body during Pls (when traveling on line R in the figure) until backlash cancellation. In FIG. 11A, the line F1 shows a flow of diaphragm → open drive, but actually moves along the line F2.

  FIG. 11B shows an example where the driving direction is reversed from the opening direction to the aperture direction. The aperture is driven to open in the opening direction Qa along the open-open control AV value line Q, and is at the current aperture value Q2. It is assumed that the target AV value P2 is instructed from the camera body at this time. At this time, the CPU 41 compares the previous driving direction, the current AV value Q2 and the target AV value P2, and determines whether or not the driving is in the aperture direction. In the example shown in FIG. 11B, since the target AV value P2 is larger than the current AV value Q2, the driving is performed in the aperture direction.

  In this case, since driving is performed in the aperture direction, Pls that matches the target AV value is searched with reference to the “aperture → aperture AV interpolation table” (see FIG. 9A), and the current Pls and target Drive for the difference in Pls. Pls is currently transmitted to the camera body during Pls (when traveling on line R in the figure) until backlash cancellation. In FIG. 11B, the line F3 shows the flow of diaphragm → open drive, but actually moves along the line F4.

  Next, an application example of aperture control in the present embodiment will be described. During moving image shooting, driving is performed at a slow speed in order to suppress flickering due to a change in the light amount of the diaphragm and to reduce driving sound. For example, the aperture is driven at a maximum speed of about 5000 pps (pulses / sec) during still image shooting, but is driven at about 120 pps (1/6 AV / sec) during moving image shooting. Therefore, as an application example 1, the backlash Pls drive portion (when traveling at R in FIG. 11) may be driven at a high speed, and after backlash cancellation, it may be driven at a normal speed. The stepping motor can be driven by self-activation if it is 500 to 1000 pps. Further, in the still image shooting state, it is driven at a normal speed. Whether the moving image shooting state or the still image shooting state is determined is determined based on a moving image flag or the like for setting the moving image state.

  As described above, in the application example 1, in the drive region of the aperture drive unit (aperture drive mechanism 21) for canceling backlash, the actuator (aperture motor 81 (AVMT75)) of the aperture drive unit is moved at the first speed. In the drive region of the actuator that is driven and the diaphragm blade 91 moves, the actuator is driven at a second drive speed higher than the first drive speed. Also, the driving speed of the aperture drive unit is slower during moving image shooting than during still image shooting.

  As an application example 2, when the moving image is driven at a slow speed, the AV value at the time of driving is returned to the camera body until the backlash is canceled. Further, as an application example 3, when the aperture is advanced to the minimum aperture (for example, F22) or when the aperture is advanced to the full aperture, the next step is to remove the hiss in the reverse direction, so an instruction is received from the camera body. When not, it may be driven first by the amount of backlash cancellation in the lens.

  Furthermore, as application example 4, frequently used aperture amounts and previously used aperture amounts are stored, and backlash cancel driving is performed in advance before the next operation. Furthermore, as an application example 5, the next operation direction may be predicted by a command, and backlash cancel driving may be performed in advance.

  Next, the operation in this embodiment will be described with reference to the flowcharts shown in FIGS. This flow is executed by the CPU 41 according to a program stored in the storage unit 37.

  When the flow for driving the aperture target position is entered, first, the camera body 200 (body) transmits the target drive AV value and the target drive speed (I1). In some cases, a hiss removal instruction is also transmitted. Subsequently, the CPU 41 performs target AV correction and driving direction determination (S1). Here, the target AV value received from the camera body 200 is compared with the current AV value to determine the drive direction. Detailed operation of the target AV and driving direction determination will be described later with reference to FIGS. 13 and 14.

  Next, it is determined whether or not forward driving is performed (S3). Here, the determination is made based on the driving direction determined in step S1. The forward direction refers to a driving direction in the same direction as the previous time, such as “aperture-aperture drive” and “open-open drive”.

  If the result of determination in step S3 is forward drive, target relative Pls calculation is performed in the forward direction (S5). Here, the target relative Pls calculation is performed in accordance with the currently used AV adjustment value table. The target relative Pls is the number of pulses (number of steps) applied to the aperture motor 81 (AVMT75) in order to drive from the current position to the target position. This detailed operation will be described later with reference to FIG.

  On the other hand, if the result of determination in step S3 is that forward drive has not been made, target relative Pls calculation is performed with hiss removal (calculation) drive (S7). Here, as described with reference to FIG. 11, the driving direction is reversed. This detailed operation will be described later with reference to FIG.

  If target relative Pls calculation is performed in step S5 or S7, next, aperture drive is performed (S9). Here, aperture driving is performed using the target relative Pls calculated in step S5 or S7. This detailed operation will be described later with reference to FIG. When the aperture driving is performed, the flow of the aperture target position driving is ended, and the original flow is returned to.

  Next, detailed operations of target AV correction and drive direction determination in step S1 will be described with reference to the flowchart shown in FIG. In this flow, first, the target drive AV value is received (S11), and the current ZM position is grasped (S13). The ZM position (zoom position) is acquired by a zoom encoder (not shown).

  Subsequently, the effective open AV value of the current zoom position is acquired from the open AV table (S15). Here, the effective open AV value corresponding to the current zoom position acquired from the ZM encoder is acquired using an open AV table (not shown) that stores the relationship between the nominal open AV value and the effective open AV value. The effective open AV value is Fno calculated by optical design, and it can be said to be effective Fno in the open position because the focus lens position is taken into consideration. There is a nominal open AV value for this effective open AV value, and this nominal open AV value is calculated by Fno = focal length / effective aperture. This nominal open AV value is used when the aperture value is displayed on the camera body 200. The difference between the effective open AV value and the nominal open AV is within ± 5%.

  Once the effective open AV value is acquired, it is next determined whether or not the target AV value is smaller than the effective open AV value (S17). Here, the effective open AV value acquired in step S15 is compared with the target AV value received in step S11.

  If the result of determination in step S17 is that the target AV value is smaller than the effective open AV value, it is rounded to the effective open AV value (S19). Since the aperture value cannot be made smaller than the effective open AV value, the target AV value is set as the effective open AV value in this step.

  If the target AV value is not smaller than the effective open AV value after rounding to the effective open AV value in step S19 or as a result of the determination in step S17, the corrected target AV value is set (S21). Here, the AV value rounded to the effective open AV value in step S19 or the target AV value received from the camera body 200 is determined as the target AV value.

Once the target AV value is determined, the current AV value is then grasped (S23), and the previous driving direction is grasped (S25). Then, a direction to be driven this time and a table to be referred to are determined (S27). Here, the target AV value is compared with the current AV value,
-If target AV value> current AV value, it is determined to drive in the aperture direction,
・ If the target AV value is less than the current AV value, it is determined to drive in the opening direction.
• If the target AV value and the current AV value are the same, the drive is not performed.

Also, using the previous drive direction information and the above-described drive direction information,
・ If it is open → open direction, or if it is aperture → aperture direction, it is judged as forward drive,
-If it is open → aperture direction, or if aperture → open direction, it is determined that the hysteresis removal drive. The driving in the reverse direction is referred to as “his removal (calculation) driving” for convenience of explanation.

  When the table to be referred to is determined in step S27, it is next determined whether or not hiss removal driving occurs (S31). In step S27, determination is made based on whether or not the drive direction is hiss removal (calculation) drive.

  As a result of the determination in step S31, if no hiss removal driving occurs, it is determined whether or not opening → open driving (S33). Here, since the driving direction is determined in step S27, the determination is made based on the determination result.

  If the result of determination in step S33 is open → open drive, drive is performed in the forward direction by opening → open (S35). On the other hand, if the result of determination is not open → open drive, drive is performed in forward direction drive with aperture → stop (S37). When the drive direction is determined in these steps, the flow returns to the original flow, and the diaphragm is actually driven in the above-described step S9.

  On the other hand, if the result of determination in step S31 is that hiss removal driving has occurred, then Pls that matches the current AV value is searched from the reference table (S41). In this case, the reference table is changed, that is, in the case of aperture-throttle drive in the previous drive, the table is changed to the open-open drive table, and conversely, the aperture is opened in the previous drive- If it is an open drive, the table is changed to an aperture-aperture drive table. A search is made in the changed table of Pls that matches the current AV value.

  Also, the current AV value is returned in the His removal Pls section (S43). During backlash cancellation driving in FIG. 11 (section of line R in FIG. 11), the current AV value is transmitted to the camera body 200 as aperture value information. The transmission timing of the current AV value is performed in accordance with the synchronization timing (I11) from the camera body. That is, at the time of hiss removal driving, during backlash cancellation, the AV value at the time of starting backlash cancellation is transmitted at the same timing until the backlash cancellation is completed. In forward driving, the current AV value is transmitted in synchronization with the synchronization timing.

  If Pls that matches the current AV value is searched from the reference table in step S41, it is next determined whether or not the opening → stop driving (S45). Here, since the driving direction is determined in step S27, the determination is made based on the determination result.

  If the result of determination in step S45 is that opening → throttle driving, driving is performed by opening → hising removal driving (S47). Here, drive control as described with reference to FIG. On the other hand, if it is not opening → throttle driving, driving is performed with hiss removal driving with diaphragm → opening (S49). Here, the drive control described with reference to FIG. When the drive direction is determined in these steps, the flow returns to the original flow, and the diaphragm is actually driven in the above-described step S9.

  Next, the detailed operation of “refer to Pls matching current AV value from reference table” in step S41 will be described with reference to FIG. As described above, the current control AV value is returned from the camera body 200 to the camera body 200 in response to the synchronization timing signal. In this flow, during the hysteresis removal period, the AV value (current AV value) that was stopped before driving is continuously returned.

  In this flow, the target absolute Pls is searched from the AV interpolation table in the direction opposite to the target AV value (S51). In the search for the target AV value, the interpolation AV table in the direction to be driven is referred to. In the case of driving to remove the hysteresis by aperture → open, the open → open interpolation AV table is referred to. On the contrary, if it is open → drawing with a diaphragm, refer to the aperture → aperture interpolation AV table. The AV value closest to the target AV value is searched from the column of the current zoom position in the referenced table. The narrowing step of the row having the AV value becomes the target absolute Pls (hereinafter referred to as target absolute Pls, also referred to as Trg_Pls).

  If the target absolute Pls is retrieved, it is next determined whether or not a reverse has occurred between the AV value of the target absolute Pls and the AV value of the current absolute Pls (S53). The retrieved Pls determines whether the backlash is completely removed Pls. If the result of determination in step S53 is that reverse rotation has not occurred, backlash cancellation has been performed.

  If the result of determination in step S53 is that reverse rotation has occurred, next, target absolute Pls = target absolute Pls + 1Pls (advance 1 Pls in the driving direction) (S55). In the case of reverse rotation or the same value, since the backlash cancellation has not been reliably performed, the target absolute Pls is advanced by 1 Pls (Trg_Pls = Trg_Pls + 1). In addition, +1 is a direction advanced in the driving direction. The operation of advancing by 1 Pls in the driving direction will be described later with reference to FIGS. 19 (a) and 20 (a).

  When 1 Pls is advanced in the driving direction in step S55, or when the reverse rotation has not occurred as a result of the determination in step S53, the hysteresis removal Pls is determined (S57). Here, Pls that matches the current AV value is determined. When the hysteresis removal Pls is determined, the flow returns to the original flow. Note that the current AV value (AV value that was stopped before driving during driving) is returned as a response value to the camera body 200 until the driving of the backlash canceling Pls is completed after the driving is started. . In still image driving, since it ends in a short time, the frequency of occurrence is low. However, in the aperture driving of moving images (including live view), this response occurs because the driving speed is slow.

  Next, forward driving (FIG. 12) in step S5 will be described with reference to the flowchart shown in FIG.

  First, the target absolute Pls is searched from the target AV value and the forward AV interpolation table (S61). If the forward drive is performed with the aperture → the aperture, the aperture → aperture interpolation AV table (FIG. 9A) is referred to. On the other hand, in the case of forward → open and forward drive, the open → open interpolation AV table (see FIG. 9B) is searched for the AV value closest to the target AV value from the column of the current zoom position of the referenced table. The narrowing step of the row having the AV value becomes the target absolute Pls, and if the target absolute Pls is the same as the current absolute Pls, the driving is not performed.

  If the target absolute Pls is searched in step S61, next, the target relative Pls is calculated (S63). Here, relative drive Pls (Drv_dir_Pls) is calculated from (target absolute Pls−current absolute Pls). When the forward driving flow ends, the original flow returns.

  Next, the detailed operation of the hiss removal (calculation) drive (FIG. 12) in step S7 will be described with reference to FIG.

  When entering the flow for driving hiss (calculation), first, the target absolute Pls is retrieved from the AV interpolation table in the direction opposite to the target AV value (S71). In the target AV value search, the interpolation AV table in the direction to be driven is referred to. If the forward drive is performed with the aperture → the aperture, the aperture → aperture interpolation AV table (FIG. 9A) is referred to. On the other hand, in the case of forward → open and forward drive, the open → open interpolation AV table (see FIG. 9B) is searched for the AV value closest to the target AV value from the column of the current zoom position of the referenced table. To do.

  If the target absolute Pls is searched in step S71, it is next determined whether or not a reverse has occurred between the AV value of the target absolute Pls and the AV value of the current absolute Pls (S73). If the result of this determination is that reverse rotation has occurred, target absolute Pls = target absolute Pls + 1Pls (advance 1 Pls in the drive direction) (S75). Since the operations in steps S73 and S75 are the same as those in steps S53 and S55 (see FIG. 15), detailed description thereof is omitted.

  When 1 Pls is advanced in the driving direction in step S75, or when the reverse rotation has not occurred as a result of the determination in step S73, the target relative Pls is calculated (S77). Here, relative drive Pls (Drv_dir_Pls) is calculated from (target absolute Pls−current absolute Pls). When the flow for hiss removal (calculation) driving is completed, the flow returns to the original flow.

  Next, the aperture drive (see FIG. 12) in step S9 will be described using the flowchart shown in FIG.

  When the diaphragm driving flow is entered, parameter setting is first performed (S81). Here, parameters for driving the aperture motor 81 (AVMT 75) are set. Examples of parameters here include the number of driving Pls, excitation voltage, acceleration / deceleration parameters, speed setting, excitation time, and the like. Once the parameters are set, next, initial excitation is performed (S83). In the present embodiment, the aperture motor 81 is a stepping motor (pulse motor), and performs initial excitation on this motor.

  Once the initial excitation is performed, acceleration driving is performed (S85), and when a predetermined speed is reached, constant speed driving is performed (S87). When it reaches the vicinity of the target position, it performs deceleration driving (S89), and when it reaches the target position, it stops and performs holding excitation (S91). When the diaphragm driving flow ends, the flow returns to the original flow.

  Next, a specific operation in the hysteresis removal (calculation) drive (see FIG. 17) will be described with reference to FIGS. FIG. 19 shows the drive in the direction of aperture → opening, FIG. 19 (a) shows the case where the reverse rotation occurs, and FIG. 19 (b) shows the case where the reverse rotation does not occur.

  In FIG. 19A, a line P is a line connecting the aperture → aperture control AV value, and a line Q is a line connecting the open → open control AV value. P3 is the current AV value (= current Pls), and Q3 is the target AV value. When the target AV value Q3 is compared with the current AV value P3, the target AV value Q3 is smaller, so it is determined that the drive is in the opening direction. The target AV value Q3 does not have a corresponding step value (Pls) directly.

In the search of the target absolute value Pls from the target AV value Q3, the AV value closest to the target AV value Q3 is searched, and the target AV value is rounded to the closest AV value Q3 (flow of F5 in FIG. 19A). . When this rounded AV value Q3 is compared with the current AV value P3,
(Rounded target AV value Q3) ≧ (Current AV value P3)
Thus, reverse rotation occurs.

  Since reverse rotation has occurred, the target absolute Pls is advanced by 1 Pls in the opening direction. The AV value Q5 corresponding to the target absolute Pls advanced by 1 Pls is set as the target AV value (flow of F6 in FIG. 19A). Thus, the target AV value and the target absolute Pls for which the backlash cancellation has been performed are determined.

In FIG. 19B, since the target AV value Q7 is smaller than the current AV value (= current Pls) P7, it is determined that the drive is in the opening direction. In the search of the target absolute value Pls from the target AV value Q7, an AV value close to the target AV value Q7 is searched, and the target AV value is rounded to the AV value Q8 (flow of F7 in FIG. 19B). When compared with the current AV value P7,
(Rounded target AV value Q8) <(Current AV value P7)
Thus, no reversal has occurred. Thus, the target AV value and the target absolute Pls for which the backlash cancellation has been performed are determined.

  FIG. 20 shows the drive in the opening → stop direction, FIG. 20A shows the case where reverse rotation occurs, and FIG. 20B shows the case where reverse rotation does not occur. Q9 is the current AV value (= current Pls), and P9 is the target AV value. When the target AV value P9 is compared with the current AV value Q9, the target AV value P9 is smaller, so it is determined that the drive is in the aperture direction. The target AV value P9 does not have a corresponding step value (Pls) directly.

In the search of the target absolute value Pls from the target AV value P9, the AV value closest to the target AV value P9 is searched, and the target AV value is rounded to the closest AV value P10 (flow of F8 in FIG. 20A). . When this rounded AV value P10 is compared with the current AV value Q9,
(Rounded target AV value P10) ≧ (Current AV value Q9)
Thus, reverse rotation occurs.

  Since reverse rotation has occurred, the target absolute Pls is advanced by 1 Pls in the aperture direction. The AV value P11 corresponding to the target absolute Pls advanced by 1 Pls is set as the target AV value (flow of F8 in FIG. 20A). Thus, the target AV value and the target absolute Pls for which the backlash cancellation has been performed are determined.

In FIG. 20B, since the target AV value P12 is larger than the current AV value (= current Pls) Q12, it is determined to drive in the aperture direction. In the search of the target absolute value Pls from the target AV value P12, an AV value close to the target AV value P12 is searched, and the target AV value is rounded to the AV value P13 (flow of F10 in FIG. 20B). When compared with the current AV value Q12,
(Rounded target AV value P13) <(Current AV value Q12)
Thus, no reversal has occurred. Thus, the target AV value and the target absolute Pls for which the backlash cancellation has been performed are determined.

  As described above, in one embodiment of the present invention, a driving force is transmitted to the diaphragm blade 91 that limits the amount of light, and the diaphragm blade is driven in the opening direction or the narrowing-down direction. And the 1st data (for example, refer to Drawing 9 (a)) showing the relation between the amount of drive of diaphragm blade 91 when driving diaphragm blade 91 in the narrowing-down direction, and the effective diaphragm value, or the diaphragm blade is driven in the open direction Second data (for example, see FIG. 9B) representing the relationship between the driving amount of the diaphragm blade 91 and the effective diaphragm value is read from the memory, and the first data is used when the diaphragm blade 91 is driven in the narrowing direction. The driving amount of the diaphragm blade 91 is controlled by referring to the reference value (see S37 in FIG. 14). When the diaphragm blade 91 is driven in the opening direction, the driving amount of the diaphragm blade 91 is controlled by referring to the second data (see FIG. 14). (See S35 in FIG. 14) (see S5 in FIG. 12, FIG. 16). Therefore, smooth aperture control can be performed both in the aperture direction and in the open direction.

  In one embodiment of the present invention, when driving the aperture drive unit by reversing the drive direction, referring to the first data and the second data, the aperture blade 91 at a predetermined effective aperture value is set in the aperture direction. The backlash is canceled by driving the aperture drive unit by the difference between the drive amount of the aperture blade when driving and the drive amount of the aperture blade when driving the aperture blade in the opening direction at the predetermined effective aperture value. (See S47 and S49 in FIGS. 11 and 14) (see S7 and FIG. 17 in FIG. 12). For this reason, it is possible to quickly remove the influence of backlash that occurs during aperture driving and perform smooth aperture control.

  In one embodiment of the present invention, a reset position of 8 Pls is used as the reference position of the diaphragm on the mechanical end side from the point where the AVPI 77 is inverted. However, the present invention is not limited to this, and other aperture reference positions may be determined to generate and control the first and second tables. In the embodiment of the present invention, the backlash is canceled in the entire driving range of the diaphragm blade 91. However, the present invention is not limited to this. For example, as shown in the P region shown in FIG. The backlash may be canceled only in a large rush range.

  In the present embodiment, the digital camera is used as the photographing device. However, the camera may be a digital single-lens reflex camera or a compact digital camera, and may be used for moving images such as video cameras and movie cameras. It may be a camera, or may be a camera built into a mobile phone, a smart phone, a personal digital assistant (PDA), a game machine, or the like. In any case, the present invention can be applied to any apparatus for photographing having an aperture.

  In addition, regarding the operation flow in the claims, the specification, and the drawings, even if it is described using words expressing the order such as “first”, “next”, etc. It does not mean that it is essential to implement in this order.

  The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, you may delete some components of all the components shown by embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 11 ... Shooting lens, 11a ... Lens, 11b ... Focus lens, 11c ... Lens, 13 ... Diaphragm, 21 ... Diaphragm drive mechanism, 23 ... Diaphragm reference position detection part, 25... Focus lens drive mechanism, 27... Focus lens reference position detection unit, 35... MF position detection unit, 37... Storage unit, 41. ... ZM ring, 61 ... MF photointerrupter binarization circuit, 63 ... MF photointerrupter, 65 ... MF photointerrupter driver, 67 ... LD photointerrupter binarization circuit, 69 ... LD photo interrupter, 71 ... motor driver, 73 ... LD motor, 75 ... AV motor, 77 ... AV photo interrupter, 79 ... AV photo Interrupter binarization circuit, 81... Aperture motor, 83... Motor pinion gear, 85... Connection gear, 85 a. Nesting spring, 91... Diaphragm blade, 91a... Cam hole, 91b... Pin, 92... Fixing member, 93. Part, 95b ... pin, 100 ... interchangeable lens, 200 ... camera body, 201 ... imaging device

Claims (5)

Aperture blades that limit the amount of light ;
A diaphragm drive section for driving the upper Symbol diaphragm blade opening direction, or narrowing direction,
First data representing the relationship between the driving amount of the diaphragm blade and the effective aperture value when the diaphragm blade is driven in the narrowing-down direction with reference to the driving amount of the diaphragm blade at a predetermined open aperture value, and the diaphragm blade A memory for storing second data representing the relationship between the driving amount of the diaphragm blades and the effective aperture value when driving in the open direction;
When the diaphragm blades are driven in the narrowing direction, the driving amount of the diaphragm blades is controlled with reference to the first data, and when the diaphragm blades are driven in the open direction, the diaphragm is referred to with the second data. A drive control unit for controlling the driving amount of the blade;
An aperture value detector for detecting an aperture value corresponding to the position of the aperture blade;
A lens unit having
A camera body to be transmitted to the drive control unit goals aperture,
With
The drive control unit determines the drive direction from the current aperture value detected by the aperture value detection unit and the target aperture value, and reverses the drive direction to drive the aperture drive unit when the first drive unit is driven. With reference to the data and the second data, the driving amount of the diaphragm blades when driving the diaphragm blades in the narrowing direction at the effective diaphragm value corresponding to the current diaphragm value, and the current diaphragm value The backlash is canceled by driving the diaphragm drive unit by the difference from the driving amount of the diaphragm blade when driving the diaphragm blade in the opening direction at the effective aperture value,
An image pickup apparatus, wherein during the backlash cancel operation, data corresponding to the current aperture value detected before the backlash cancel operation is started is transmitted to the camera body .   The drive control unit uses the first data or the second data to be referred to corresponding to the determined drive direction, and drives the drive among the two drive amounts of the aperture blade corresponding to the target aperture value. The imaging apparatus according to claim 1, wherein the driving amount of the diaphragm blades is controlled after the backlash canceling operation based on a driving amount positioned in a direction.   The diaphragm drive unit includes an actuator that drives the diaphragm blades. In the drive region of the diaphragm drive unit for canceling the backlash, the diaphragm blades are driven by driving the actuator at a first speed. The imaging apparatus according to claim 2, wherein the actuator is driven at a second driving speed higher than the first driving speed in a driving area of the actuator.   The imaging apparatus according to claim 1, wherein the moving speed of the aperture driving unit is slower during moving image shooting than during still image shooting. And transmitting the driving force to the diaphragm blades to limit the amount of light, restrictor blade open direction, or a lens unit having a diaphragm drive section for driving the narrowing direction, the camera body to transmit the goal aperture value to the lens unit In a diaphragm control method of an imaging apparatus having
The first data representing the relationship between the driving amount of the diaphragm blade and the effective aperture value when the diaphragm blade is driven in the narrowing-down direction based on the driving amount of the diaphragm blade at a predetermined open aperture value, or the diaphragm blade A reading step of reading out from the memory second data representing the relationship between the driving amount of the diaphragm blades and the effective aperture value when driving in the open direction;
When the lens unit drives the diaphragm blades in the narrowing direction, the driving amount of the diaphragm blades is controlled by referring to the first data, and when the diaphragm blades are driven in the open direction, refer to the second data. A drive control step for controlling the drive amount of the diaphragm blades;
And the drive control step comprises:
When the driving direction is determined from the current aperture value and the target aperture value and the driving direction is reversed to drive the aperture driving unit, the current aperture is referred to by referring to the first data and the second data. A driving amount of the diaphragm blades when driving the diaphragm blades in the narrowing-down direction at an effective diaphragm value corresponding to the value, and when driving the diaphragm blades at an effective aperture value corresponding to the current diaphragm value in the opening direction. The backlash is canceled by driving the diaphragm drive unit by the difference from the driving amount of the diaphragm blades,
During the backlash canceling operation, data corresponding to the current aperture value before starting the backlash canceling operation is transmitted to the camera body .
An aperture control method for an imaging apparatus.