JP2017090497A - Imaging device, control method of the same, and control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately perform correction of positional displacement of a lens barrel and achieve desired optical performance.SOLUTION: A camera comprises a zoom moving mirror barrel 72 that is movable along an optical axis, and a driving range in which the zoom moving lens barrel is driven is divided into a plurality of areas. A control circuit 90 counts the number of times the zoom moving lens barrel is driven in each of the areas to obtain the number of counts, and corrects a drive position of the zoom moving lens barrel according to the number of counts when controlling the driving of the zoom moving lens barrel.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an imaging apparatus having a lens barrel including at least a zoom mechanism, a control method thereof, and a control program.

  In general, an imaging apparatus having a lens barrel having a zoom and focus mechanism and a control mechanism for operating the lens barrel is known.

  In such an imaging apparatus, when zoom and focus driving are repeatedly performed, wear occurs on the sliding portion of the lens barrel. In particular, many imaging devices (hereinafter referred to as surveillance cameras) used for monitoring purposes are provided with a drive mechanism that changes the direction of the lens barrel by pan and tilt drive. And since a surveillance camera is installed in arbitrary places, such as a ceiling, and is used continuously for a long period of time, the frequency | count of operation of a drive mechanism increases.

  Therefore, surveillance cameras are required to have higher durability performance than imaging devices used for other purposes. Note that the durability performance refers to performance in which the drive mechanism is driven without any problem and satisfies the optical performance and does not change from the initial setting conditions.

  Incidentally, there is a so-called preset patrol function as a function unique to the surveillance camera. For example, in a PTZ (pan / tilt / zoom) network camera having a preset patrol function, a plurality of shooting spots are handled as patrol spots and managed as a patrol setting in combination with information such as the shooting order and staying time.

  In the PTZ network camera, shooting is performed while sequentially patrol spots according to the patrol setting. By repeating the preset tour based on the patrol setting at a predetermined interval, the user (monitorer) can periodically obtain images of a desired plurality of places using a single surveillance camera.

  In the above-described preset tour, since photographing is repeated under preset conditions, zoom and focus driving, and pan and tilt driving are repeatedly performed.

  By the way, if zoom and focus driving are repeatedly performed, wear of the sliding portion of the lens barrel involved in zoom and focus driving increases. When wear of the sliding portion increases, the position of the lens barrel changes from the initially set position, and the angle of view and the in-focus state change. If the in-focus state changes from the initial setting, the image is out of focus, resulting in a blurred image.

  In general, in a surveillance camera, a user shoots an image, rarely observes the image, and often observes a recorded image at a later date. Considering the use of such a monitoring camera, a change from the initial setting becomes a big problem.

  For this reason, there is an imaging device that corrects the position error of the lens barrel due to wear of the sliding portion or the mechanism portion. In this imaging device, the position change due to wear of the abutting portion that is the origin position of the lens barrel Driving control is performed so that the driving amount of the lens barrel is changed by an amount that allows for the amount (see Patent Document 1).

JP-A-6-202735

  However, since the image pickup apparatus described in Patent Document 1 only corrects the positional deviation of the origin of the lens barrel, the correction is not performed unless the so-called origination operation is performed. . For this reason, when the camera is used continuously for a long period of time as in an imaging device used for a surveillance camera, the origin finding operation is not performed for a long period of time, and the lens barrel position shift correction is not performed. It will not be done.

  Furthermore, in the imaging device described in Patent Document 1, since correction is performed in consideration of the amount corresponding to the wear of the abutting portion that is the origin position of the lens barrel, the entire zoom range and focus range are uniform. It can only be corrected. For this reason, when the range in which the lens barrel is driven is biased, only uniform correction can be performed even when the amount of wear differs at each location of the abutting portion. Therefore, undercorrection or overcorrection may occur, and desired optical performance may not be obtained.

  Accordingly, an object of the present invention is to provide an image pickup apparatus that can accurately correct the positional deviation of the lens barrel and can obtain desired optical performance in an image pickup apparatus used for monitoring purposes, and a control method thereof, and It is to provide a control program.

  In order to achieve the above object, an imaging apparatus according to the present invention is an imaging apparatus having a zoom lens movable along an optical axis, wherein a driving range in which the zoom lens is driven is divided into a plurality of areas. And a count unit that counts the number of times the zoom lens is driven in each of the areas and obtains the number of counts, and a control that corrects the drive position of the zoom lens according to the number of counts when driving the zoom lens. And means.

  A control method according to the present invention is a method for controlling an imaging apparatus having a zoom lens movable along an optical axis, wherein a driving range in which the zoom lens is driven is divided into a plurality of areas. A counting step for counting the number of times the zoom lens is driven to obtain the number of times, and a control step for correcting the driving position of the zoom lens according to the number of times of counting when the zoom lens is driven and controlled. It is characterized by that.

  A control program according to the present invention is a control program used in an imaging apparatus having a zoom lens movable along an optical axis, wherein a driving range in which the zoom lens is driven is divided into a plurality of areas. A counting step of obtaining a count number by counting the number of times the zoom lens is driven in each of the areas in a computer included in the imaging device, and driving the zoom lens according to the count number when driving the zoom lens is controlled. And a control step of correcting the position.

  According to the present invention, it is possible to correct the positional deviation of a lens barrel such as a zoom lens with high accuracy, and to obtain desired optical performance.

It is a perspective view which decomposes | disassembles and shows the lens barrel used with an example of the imaging device by embodiment of this invention. It is a figure which shows the locus | trajectory of a movement of the 2nd group barrel, the 3rd group barrel, and the 4th group barrel shown in FIG. It is a figure which shows the locus | trajectory of the 2nd group barrel and the 3rd group barrel followed after the abrasion by zoom drive arises with the locus | trajectory shown in FIG. It is a figure which shows an example of the locus | trajectory of a lens barrel when a zoom drive range has deviation. It is a block diagram which shows the example about the structure of a camera provided with the lens-barrel shown in FIG. 6 is a flowchart for explaining drive control performed by the camera shown in FIG. 5.

  Hereinafter, an example of an imaging apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is an exploded perspective view showing a lens barrel used in an example of an imaging apparatus according to an embodiment of the present invention.

  An imaging device (hereinafter simply referred to as a camera) has a lens barrel, and the lens barrel has a first group barrel 1, a second group barrel 2, a third group barrel 3, and a fourth group barrel 4. doing. A zoom drive motor 6 is disposed behind the four lens barrels 4. The lens barrel further includes a zoom sensor 7, a focus drive motor 8, a focus rack 9, and a focus sensor 10.

  As will be described later, a cam shaft 12 is inserted into the cam (cam member) 11, and a first cam follower 13 and a second cam follower 14 are positioned in the cam 11. The lens barrel includes a first guide bar 15, a second guide bar 16, a third guide bar 17, a fourth guide bar 18, and a fifth guide bar 19, and a backlash removing spring 20. I have. Note that an imaging element 21 is arranged at the rear stage of the fourth group barrel 4.

  The first group barrel 1 holds a first lens group (not shown) and is supported by a fixed barrel (not shown). The second group barrel 2 is one of zoom movable barrels that hold a second lens group (not shown) that is a zoom lens group.

  In the second group barrel 2, a sleeve portion 2a and a U-shaped groove portion 2b are formed. The sleeve portion 2 a is supported by the first guide bar 15, and the U-shaped groove portion 2 b is supported by the second guide bar 16. Accordingly, the second group barrel 2 can move along the first guide bar 15 and the second guide bar 16, that is, along the optical axis. Further, the second group barrel 2 is formed with a cam follower mounting portion 2c, and a first cam follower 13 is mounted on the cam follower mounting portion 2c.

  The third group barrel 3 is one of zoom movable barrels that hold a third lens group (not shown) that is a zoom lens group. In the third group barrel 3, a sleeve portion 3a and a U-shaped groove portion 3b are formed. The sleeve portion 3 a is supported by the third guide bar 17, and the U-shaped groove portion 3 b is supported by the second guide bar 16. As a result, the third group barrel 2 is movable along the third guide bar 17 and the second guide bar 16, that is, along the optical axis. Further, the third group barrel 3 is formed with a cam follower mounting portion 3c, and a second cam follower 14 is mounted on the cam follower mounting portion 3c.

  A cam shaft 12 is inserted through a hole 11 a formed in the center of the cam 11, and the cam 11 is engaged with the cam shaft 12 so as to be rotatable around the cam shaft 12. The end face 11b of the cam 11 is regulated and held by the fixed barrel, and is prevented from moving in the optical axis direction. A gear portion 11 c formed at the other end of the cam 11 is connected to the gear portion of the zoom drive motor 6. Accordingly, when the zoom drive motor 6 is driven, the cam 11 rotates around the cam shaft 12.

  A first cam groove 11d and a second cam groove 11e are formed in the cam 11, and the first cam follower 13 and the second cam groove 11e are formed in the first cam groove 11d and the second cam groove 11e, respectively. The cam follower 14 is engaged. Therefore, when the cam 11 rotates, the second group barrel 2 and the third group barrel 3 are driven along the optical axis to perform zooming.

  The zoom sensor 7 is an element such as a photo interrupter, and is fixed to a fixed barrel. The zoom sensor 7 detects the origin reference position of the second group barrel 2 when the opening is shielded by the sensor flag portion 2d formed in the second group barrel 2 in accordance with the movement of the second group barrel 2. .

  The zoom drive motor 6 is a stepping motor and is driven based on the origin reference position described above. Then, according to the number of driving steps of the zoom drive motor 6, the positions of the second group barrel 2 and the third group barrel 3 in the optical axis direction change, and the zoom position changes.

  The zoom drive motor 6 is fixed to a fixed lens barrel, and power is supplied from a flexible cable (not shown).

  The fourth group barrel 4 is a focus moving barrel that holds a fourth lens group (not shown) that is a focus lens group. In the fourth group barrel 4, a sleeve portion 4a and a U-shaped groove portion 4b are formed. The sleeve portion 4 a is supported by the fourth guide bar 18, and the U-shaped groove portion 4 b is supported by the fifth guide bar 19. Thus, the fourth group barrel 2 can move along the fourth guide bar 18 and the fifth guide bar 19, that is, along the optical axis. Further, a rack mounting portion 4c is formed on the fourth group lens barrel 4, and a focus rack 9 is mounted on the rack mounting portion 4c.

  The focus rack 9 is screwed with the screw shaft portion of the focus drive motor 8, and the focus rack 9 is driven along the optical axis by the rotation of the screw shaft portion. The fourth group barrel 4 is moved along the optical axis by driving the focus rack 9.

  The focus sensor 11 is an element such as a photo interrupter and is fixed to a fixed barrel. The focus sensor 11 detects the origin reference position of the fourth group barrel 4 when the opening is shielded by the sensor flag portion 4d formed in the fourth group barrel 4 in accordance with the movement of the fourth group barrel 4. .

  The focus drive motor 8 is a stepping motor and is driven with reference to the origin reference position. Then, the position of the fourth group barrel 4 in the optical axis direction is changed according to the number of drive steps of the focus drive motor 8 to perform focusing.

  The focus drive motor 8 is fixed to a fixed barrel and is supplied with electric power from a flexible cable (not shown). For the drive control related to the zoom drive motor 6 and the focus drive motor 8, so-called open control in which the lens barrel moves according to the number of drive steps is used.

  The play removing spring 20 is a compression spring, and urges the second group barrel 2 and the third group barrel 3 in directions opposite to each other in the optical axis direction (reverse direction). As a result, backlash in the optical axis direction is suppressed between the first cam follower 13 and the first cam groove 11d. Furthermore, play in the optical axis direction is suppressed between the second cam follower 14 and the second cam groove 11e.

  The image sensor 21 is a CMOS image sensor, for example, and is fixed to a fixed lens barrel. Then, an optical image (subject image) is formed on the image sensor 21 through the lens group described above.

  FIG. 2 is a diagram illustrating movement trajectories of the second group barrel, the third group barrel, and the fourth group barrel shown in FIG.

  In FIG. 2, the horizontal axis indicates the zoom position, and the vertical axis indicates the position of the lens barrel. A trajectory 31 indicates the trajectory of the second group barrel 2, and a trajectory 32 indicates the trajectory of the third group barrel 3. A locus 33 indicates an infinite locus of the fourth group barrel 4, and a locus 34 indicates a 1 m locus of the fourth group barrel 4.

  Here, the second group barrel 2 is moved along the locus 31, the third group barrel 3 is moved along the locus 32, and the group barrel 4 is moved along the infinity locus 33, so that the object at infinity is in focus. You can zoom in.

  Further, by moving the second group barrel 2 along the trajectory 31, the third group barrel 3 along the trajectory 32, and the fourth group barrel 4 along the 1m trajectory 34, the subject 1m ahead You can zoom in and out of focus.

  The trajectory is determined optically. In the lens barrel shown in FIG. 1, the shapes of the first cam groove 11d and the second cam groove 11e formed in the cam 11 are defined as a trajectory 31 and a trajectory 32, whereby the second group barrel 2 and the third group. The lens barrel 3 is moved along a locus 31 and a locus 32, respectively. On the other hand, the fourth group lens barrel 4 is moved along the above-mentioned locus 33 or 43 by a so-called electronic cam system that drives the fourth group lens barrel 4 while controlling the drive step of the focus drive motor 8.

  In this way, by controlling the drive step of the zoom drive motor 6 and the drive step of the focus drive motor 8, the second group barrel 2, the third group barrel 3, and the fourth group barrel 4 are moved along the locus described above. Can be moved. Thus, it is possible to obtain a state in which the subject is in focus even when zooming is performed.

  Although not described here, generally, a plurality of cams corresponding to the intermediate distance are provided between the infinity locus 33 and the 1 m locus 34 so as to obtain a locus corresponding to each intermediate distance.

  By the way, when zoom driving is repeated, wear occurs in the sliding portion between the first cam follower 11d and the second cam groove 11e formed in the cam 11 and the first cam follower 13 and the second cam follower 14. .

  FIG. 3 is a diagram showing the trajectories of the second and third lens barrels traced after the wear of the zoom drive occurs along with the trajectory shown in FIG.

  In FIG. 3, a locus 35 indicates a locus of the second group barrel 2 after m times of zoom driving (m is an integer of 1 or more), and a locus 36 indicates a third group mirror after m times of zoom driving. The trajectory of the cylinder 3 is shown. A trajectory 37 indicates the trajectory of the second group barrel 2 after zoom driving is performed n times (n> m), and a trajectory 38 is a trajectory of the third group barrel 3 after zoom driving is performed n times. Indicates.

  The first cam groove 11d and the first cam follower 13, and the second cam groove 11e and the second cam follower 14 are in contact with each other by the biasing spring 20, but the contact surface is a single side. is there. For this reason, the surface to be worn becomes one side, and its locus is also shifted in one direction.

  Further, considering that the urging force of the rattling spring 20 is not constant over the entire zoom region, the amount of wear differs in the zoom region. In the illustrated example, the distance between the second group barrel 2 and the third group barrel 3 is closer on the TELE side than the WIDE (wide) side, so that the biasing force of the backlash spring is strong and the wear amount. Will increase. Further, as the number of times of zoom driving increases, the amount of wear increases, and the change in the locus increases according to the number of times of zoom driving.

  For example, when the first zoom position is set to the position 50 in the initial setting, the interval between the position of the second group barrel 2 and the position of the third group barrel 3 is the interval 50c. The angle of view of the captured image is determined by the distance between the second group barrel 2 and the third group barrel 3. Therefore, the angle of view of the captured image is an angle of view corresponding to the interval 50c.

  On the other hand, if the cam 11 is rotated to the same phase as the first zoom position 50 when the zoom drive is performed m times, the distance between the position of the second group barrel 2 and the position of the third group barrel 3 is The interval is 50f. Therefore, the angle of view of the captured image is an angle of view corresponding to the interval 50f. That is, the angle of view of the captured image changes compared to the initial setting.

  Such a phenomenon is caused by the fact that the change in the lens barrel position due to wear cannot be detected because the zoom position is controlled by open control.

  If the initially set angle of view changes after endurance, the influence becomes particularly large during so-called preset patrol. In the preset tour, an angle of view, that is, a zoom position and a focus position is set for each lens at the time of initial setting, and the set positions are repeatedly visited. For this reason, the angle of view changes as the number of zoom driving increases.

  When the zoom driving is performed m times, the interval between the second group barrel 2 and the third group barrel 3 corresponds to the interval 50c when the zoom position is the second zoom position 51. . At this time, the interval between the second group barrel 2 and the third group barrel 3 is the interval 51c, and the interval 50c and the interval 51c are equal.

  Similarly, when the zoom driving is performed n times, the interval between the second group barrel 2 and the third group barrel 3 is the same as the interval 50c when the zoom position is the third zoom position 52. . Therefore, the angle of view can be corrected by controlling the phase of the cam 11 according to the number of times of zoom driving.

  For example, when zoom driving is performed m times, correction control for moving to the second zoom position 51 is performed. Further, when zoom driving is performed n times, correction control for moving to the third zoom position 52 is performed. In this way, the angle of view does not change with respect to the initial setting.

  Therefore, in the camera according to the embodiment of the present invention. A correction table using the zoom position as a parameter is provided, and the zoom position, that is, the rotation angle of the cam 11 is corrected and controlled based on the correction table to prevent a change in the angle of view with respect to the initial setting.

  Note that the trajectories 35 to 38 shown in FIG. 3 indicate the trajectories when the zoom driving is repeatedly performed uniformly over the entire zoom region, and the amount of wear of the cam groove is constant according to the number of times of zoom driving for each zoom position. And the correction amount is determined by actually measuring and predicting the wear amount.

  Incidentally, in general, there is a bias in the zoom drive range during zoom drive. That is, in most cases, zoom driving is not performed uniformly over the entire zoom area.

  FIG. 4 is a diagram illustrating an example of the trajectory of the lens barrel when the zoom drive range is biased.

  In FIG. 4, a trajectory 39 indicates the trajectory of the second group barrel 2 after a predetermined period has elapsed from the initial state. A trajectory 40 indicates the trajectory of the third group barrel 3 after a predetermined period has elapsed from the initial state. In the locus 39, the intermediate portion 39 a has a larger amount of change from the locus 31 than the tele-side portion of the locus 39. And in the locus | trajectory 40, the intermediate part 40a has the large variation | change_quantity from the locus | trajectory 32 compared with the tele side part of the locus | trajectory 40. FIG.

  Such a phenomenon is a result of a large amount of zoom driving performed in the vicinity of the intermediate portion, and is caused by an increase in the wear amount of the cam groove in the vicinity of the intermediate portion.

  As described above, since the zoom region used varies depending on the use state of the user, the degree of change in the locus of the lens barrel caused by the wear of the cam groove also varies. As described above, even if it is attempted to correct the change in the angle of view due to the change in the distance between the second group lens barrel 2 and the third group lens barrel 3 due to wear only with the correction table using the number of times of zoom driving and the zoom position as parameters. Will occur.

  In order to avoid such an error, the zoom range is divided into a first zoom area 61, a second zoom area 62, and a third zoom area 63 here. Then, a first address 64, a second address 65, and a third address 66 are set in the first zoom area 61, the second zoom area 62, and the third zoom area 63, respectively.

  The address indicates a zoom position for control. Since the zoom position for control is determined by the number of steps from the origin reference position of the zoom motor, a position having a predetermined number of steps from the origin position is set as an address.

  Here, as will be described later, the number of times the lens barrel passes through the first address 64, the second address 65, and the third address 66 by zoom driving is counted. When the zoom position is in the first zoom area 61, the angle of view is corrected according to the number of times that the first address 64 is passed.

  Similarly, when the zoom position is in the second zoom area 62, the angle of view is corrected according to the number of passes through the second address 65. Then, when the zoom position is in the third zoom area 63, the angle of view is corrected according to the number of passes through the third address 66.

  Thus, the zoom range is divided into a plurality of zoom areas, and the number of times of driving is counted for each zoom area. The parameters used in the correction table are provided for each zoom area. As a result, even if the actual zoom drive range is not uniform, the angle of view can be corrected with high accuracy.

  In the above example, the zoom range is divided into three zoom areas. However, the number of divisions is not limited to three, and correction control can be performed with higher accuracy if the number of divisions is increased. Further, the threshold used when the angle of view is corrected according to the number of passes may be different for each zoom area.

  For example, in the zoom area on the TELE side where the amount of wear per driving frequency is large, the threshold value is made smaller than in the zoom area on the WIDE side. Considering the difference in the amount of wear per the number of times of driving and the degree of influence due to wear, if the threshold value is made different for each zoom area, the field angle can be corrected with high accuracy. Further, the threshold value may be varied according to the width of the zoom area.

  FIG. 5 is a block diagram showing an example of the configuration of a camera including the lens barrel shown in FIG.

  The camera has a lens unit 71, and the lens unit 71 includes the lens barrel described in FIG. In the following description, a lens barrel that performs a zoom operation is referred to as a zoom movement lens barrel 72, and a lens barrel that performs a focus operation is referred to as a focus movement lens barrel 76.

  The zoom moving lens barrel 72 has a zoom lens group and is driven along the optical axis by the zoom drive motor 6. Then, the zoom sensor 7 detects the origin reference position of the zoom moving barrel 72 as described above.

  The control circuit 90 controls the zoom motor driver 74 to drive the zoom drive motor 6. The control circuit 90 determines drive conditions such as the number of drive pulses and drive speed of the zoom drive motor 6 and supplies power from the zoom motor driver 74 to the zoom drive motor 6 according to the drive conditions.

  The focus moving lens barrel 76 has a focus lens group and is driven along the optical axis by the focus drive motor 8. Then, the origin reference position is detected by the focus sensor 11 as described above.

  The control circuit 90 controls the focus motor driver 78 to drive the focus drive motor 8. The control circuit 90 determines drive conditions such as the drive pulse number drive speed of the focus drive motor 8 and supplies power from the focus motor driver 78 to the focus drive motor 8 according to the drive conditions.

  The control circuit 90 performs a zoom operation by driving the zoom moving lens barrel 72 and the focus moving lens barrel 76 along the aforementioned locus (also referred to as a cam lift curve), and drives the focus moving lens barrel 76 along the optical axis. To focus. After the zoom operation and the focus operation, the image sensor 21 sends an analog image signal corresponding to the formed optical image to the image processing unit 81. The image processing unit 81 performs A / D conversion on the analog image signal, performs predetermined image processing to generate image data, and sends the image data to the control circuit 90.

  The control circuit 90 counts the number of times that the zoom moving lens barrel 72 and the focus moving lens barrel 76 have passed through a plurality of preset zoom positions (corresponding to the aforementioned addresses), and stores the count number (count number). 91.

  An operation switch 92 is connected to the control circuit 90, and the user gives various instructions to the control circuit 90 by the operation switch 92. Further, the memory 91 stores an initial set value set by a user operation and a zoom correction amount and a focus correction amount (that is, a correction table) corresponding to the above-mentioned count number. That is, the sliding portion is worn by driving the zoom movable lens barrel 72 and the drive position of the zoom movable lens barrel 72 is changed. Therefore, a wear amount corresponding to the number of times of driving (count number) is anticipated in advance. The zoom correction amount and the focus correction amount are correction amounts for correcting a change in the angle of view and a focus shift caused by the amount of change in the driving position of the zoom moving lens barrel 72 due to the wear amount.

  FIG. 6 is a flowchart for explaining drive control performed by the camera shown in FIG. Note that the processing according to the illustrated flowchart is performed under the control of the control circuit 90.

  When the drive control is started, the control circuit 90 controls the zoom motor driver 74 to drive the zoom drive motor 6 (step S101). At this time, the control circuit 90 sends a control signal to the zoom motor driver 74, and the zoom driver 74 drives the zoom drive motor 6 by the number of pulses indicated by the control signal.

  Subsequently, the control circuit 90 determines whether or not the zoom movable lens barrel 72 has passed a predetermined zoom address by driving the zoom drive motor 6 (step S102). If the predetermined zoom address is not passed (NO in step S102), the control circuit 90 returns to the process of step S101 and drives the zoom drive motor 6.

  On the other hand, when the predetermined zoom address is passed (YES in step S102), the control circuit 90 increments the count number for each zoom address and stores it in the memory 91. There are a plurality of predetermined zoom addresses as described with reference to FIG. Then, the control circuit 90 determines whether or not there is a zoom address in which the number of counts stored in the memory 91 has reached a preset number (step S104).

  If there is no zoom address at which the number of counts reaches the preset number (NO in step S104), the control circuit 90 returns to the process of step S101 and drives the zoom drive motor 6.

  On the other hand, if there is a zoom address whose count reaches the preset number (YES in step S104), control circuit 90 includes a zoom address for which the current zoom position is determined to be “present” in step S104. It is determined whether or not it is located in a zoom area (also referred to as a correction area) (step S105). The zoom area refers to a zoom range including a predetermined address as described with reference to FIG.

  If the current zoom position is not located in the zoom area including the zoom address determined as “present” (NO in step S105), the control circuit 90 returns to the process in step S101 and drives the zoom drive motor 6.

  On the other hand, when the current zoom position is located in the zoom area including the zoom address determined to be “present” (YES in step S105), control circuit 90 zooms from the correction table stored in memory 91 according to the number of counts. The correction amount is read (step S106).

  Subsequently, the control circuit 90 controls the zoom motor driver 74 in accordance with the zoom correction amount, and drives the zoom drive motor 6 by the number of pulses corresponding to the zoom correction amount to perform field angle correction (step S107). Then, the control circuit 90 ends the drive control.

  In this way, even if there is a bias in the amount of wear of the sliding portion, the zoom moving barrel 72 can be controlled with high accuracy in the zoom range, and an appropriate angle of view can be maintained.

  In the above-described example, the correction of the angle of view has been described. However, when focus correction is required, the drive control of the focus moving lens barrel 76 is performed in the same manner as the zoom moving lens barrel 72.

  As described above, according to the embodiment of the present invention, not only the lens barrel can be accurately corrected but also desired optical performance can be obtained.

  As is clear from the above description, in the example shown in FIG. 5, the control circuit 90 functions as a counting unit, and at least the control circuit 90, the zoom motor driver 74, and the zoom drive motor 6 function as a control unit.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to these embodiment, Various forms of the range which does not deviate from the summary of this invention are also contained in this invention. .

  For example, the function of the above embodiment may be used as a control method, and this control method may be executed by the imaging apparatus. Further, a program having the functions of the above-described embodiments may be used as a control program, and the control program may be executed by a computer included in the imaging apparatus. The control program is recorded on a computer-readable recording medium, for example.

[Other Embodiments]
The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

Reference Signs List 6 Zoom drive motor 8 Focus drive motor 21 Image sensor 71 Lens unit 72 Zoom moving barrel 76 Focus moving barrel 81 Image processing unit 90 Control circuit 91 Memory 92 Operation switch

Claims (10)

An imaging device having a zoom lens movable along an optical axis,
The driving range in which the zoom lens is driven is divided into a plurality of areas,
Counting means for obtaining the number of counts by counting the number of times the zoom lens is driven in each of the areas;
Control means for correcting the drive position of the zoom lens according to the number of counts when driving the zoom lens;
An imaging device comprising: A focus lens movable in the optical axis direction;
The image pickup apparatus according to claim 1, wherein the control unit corrects a drive position of the focus lens according to the number of counts when driving the zoom lens. A correction table in which a correction amount for correcting the driving position of the zoom lens corresponding to the count number is recorded in each of the areas;
The imaging apparatus according to claim 1, wherein the control unit corrects a driving position of the zoom lens with reference to the correction table.   4. The image pickup apparatus according to claim 1, wherein the control unit corrects the driving position of the zoom lens when the count number exceeds a preset threshold value. 5.   The imaging apparatus according to claim 4, wherein the preset threshold value is different in each of the areas.   6. The imaging apparatus according to claim 1, wherein the count unit increments the number of counts when the zoom lens passes a predetermined position set in the area.   The imaging apparatus according to claim 1, wherein the lengths of the areas in the optical axis direction are different from each other. A zoom movable lens barrel that holds the zoom lens, a cam follower provided in the zoom movable lens barrel, and a cam groove that engages with the cam follower and moves the zoom movable lens barrel along the optical axis are formed. And a biasing means for biasing the zoom movable lens barrel in the optical axis direction,
The image pickup apparatus according to claim 1, wherein the control unit drives the cam member to drive the zoom moving barrel along the optical axis. An image pickup apparatus control method comprising a zoom lens movable along an optical axis, wherein a driving range in which the zoom lens is driven is divided into a plurality of areas,
A counting step of obtaining the number of counts by counting the number of times the zoom lens is driven in each of the areas;
A control step of correcting the drive position of the zoom lens according to the number of counts when driving the zoom lens;
A control method characterized by comprising: A control program used in an imaging apparatus having a zoom lens movable along an optical axis, wherein a driving range in which the zoom lens is driven is divided into a plurality of areas,
In the computer provided in the imaging device,
A counting step of obtaining the number of counts by counting the number of times the zoom lens is driven in each of the areas;
A control step of correcting the drive position of the zoom lens according to the number of counts when driving the zoom lens;
A control program characterized by causing

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