JP2010060878A - Method for determining initial position of image pickup device, and method for determining initial position of optical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for determining an initial position of an image pickup device, which reduces the size of a camera shake correction mechanism, and thus reduces the size of a lens barrel without needing an excessive moving range which is not used in photographing. <P>SOLUTION: The method for determining an initial position of an image pickup device includes steps of: acquiring images with a plurality of different focal distances within a magnification variation area of an imaging optical system while stopping the image pickup device in a predetermined position; finding a position free from image movement by magnification variation on the image pickup device based on the images obtained with the plurality of different focal distances; finding a shift quantity of the image pickup device from the predetermined position so that the found position free from the image movement by magnification variation on the image pickup device is a valid pixel center of the image pickup element; and storing the shift quantity in a storage means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for determining an initial position of an image sensor or an optical element in a moving mechanism of the image sensor or an optical element to prevent camera shake during photographing.

  2. Description of the Related Art Conventionally, an active camera shake correction technique that obtains a clear image by correcting a shift of an optical axis due to blurring has been put into practical use. As a camera shake correction device in a commercially available imaging device, a device that moves an image sensor and a device that moves a part of an imaging optical system are generally used.

  The direction and amount of blurring during shooting cannot be predicted before shooting. For this reason, it is preferable to match the center of the image circle formed by the image pickup optical system with the center position of the effective pixel of the image pickup device prior to shooting so as to be able to deal with any direction.

As a method for obtaining the center position of the image circle for matching the center position of the effective pixel of the image sensor, a centering information acquisition method for obtaining a vignetting image and specifying the center position of the image circle is known ( For example, see Patent Document 1).
JP 2004-56581 A

  However, the centering information acquisition method described in Patent Document 1 must be configured to be movable beyond the movement range used for camera shake correction to a range that is not used at the time of shooting, which increases the size of the camera shake correction mechanism, and thus the lens. There is a problem that the lens barrel becomes large.

  In view of the above problems, the present invention does not require an extra movement range that is not used at the time of shooting, and can reduce the size of the camera shake correction mechanism, and thus the size of the lens barrel, and the initial position determination method of the image sensor. The purpose is to obtain a decision method.

  The above object is achieved by the invention described below.

  (1) A variable-magnification imaging optical system that guides subject light, an imaging element that photoelectrically converts subject light guided by the imaging optical system, and the imaging element in a direction orthogonal to the optical axis of the imaging optical system An image pickup device initial position determination method for an image pickup apparatus, comprising: an image pickup device moving mechanism to be moved; and a storage unit, wherein camera shake correction is performed using the image pickup device moving mechanism, wherein the image pickup device is stopped at a predetermined position. In this state, an image is acquired at a plurality of different focal lengths in the variable magnification region of the imaging optical system, and a change on the imaging device is performed based on images obtained at a plurality of different focal lengths. A step of obtaining a position where there is no movement of the image due to magnification, and the position where there is no movement of the image due to scaling on the obtained imaging element is the effective pixel center of the imaging element, Work to find the amount of displacement from the position When the imaging device initial position determination method characterized by having the steps of storing the shift amount in the storage means.

  (2) The imaging element initial position determination method according to (1), wherein the plurality of focal lengths are a wide-angle end and a telephoto end of the imaging optical system.

  (3) The imaging element initial position determination method according to (1) or (2), wherein the subject in the step of acquiring images at a plurality of focal lengths is a light spot.

  (4) An imaging optical system capable of zooming to guide subject light, an imaging element for photoelectrically converting subject light guided by the imaging optical system, and at least one optical element of the previous imaging optical system is moved. Optical element initial position determination method for an image pickup apparatus, which includes an optical element moving mechanism that moves an image position in a direction orthogonal to the optical axis, and a storage unit, and performs camera shake correction using the optical element moving mechanism And obtaining the images at a plurality of different focal lengths in the variable magnification region of the imaging optical system in a state where the optical element is stopped at a predetermined position, and obtained at a plurality of different focal lengths. A step of obtaining a position where the image does not move due to zooming based on the obtained image, and a position of the image due to scaling at the center of the effective pixel of the image sensor based on the obtained position where the image does not move due to scaling. No movement So that the the step of calculating a shift amount from the predetermined position of the optical element, the optical element an initial position determination method characterized by having the steps of storing the shift amount in the storage means.

  (5) The optical element initial position determination method according to (4), wherein the plurality of focal lengths are a wide-angle end and a telephoto end.

  (6) The optical element initial position determination method according to (4) or (5), wherein the subject in the step of acquiring images at a plurality of focal lengths is a light spot.

  According to the present invention, an image pickup device initial position determination method and an optical device initial position determination method that do not require an extra movement range that is not used at the time of photographing, and that can reduce the size of the camera shake correction mechanism and, in turn, the size of the lens barrel. Can be obtained.

  Hereinafter, the present invention will be described in detail by embodiments, but the present invention is not limited thereto.

  FIG. 1 is a diagram illustrating an example of an internal arrangement of main component units of the imaging apparatus 100 according to the present embodiment. FIG. 3 is a perspective view of the imaging apparatus 100 as viewed from the subject side.

  As shown in the figure, in the imaging apparatus 100, a lens barrel 50 including a bending imaging optical system capable of zooming is arranged as shown in the figure, and an opening 51 is arranged to take in a subject light beam. The opening 51 is provided with a lens barrier (not shown) that is in an open state that exposes the opening 51 and a closed state that covers the opening 51.

  Reference numeral 52 denotes a flash light emission window. Reference numeral 53 denotes a flash unit including a reflector, a xenon tube, other main capacitors, a circuit board, and the like disposed behind the flash light emission window. Reference numeral 54 denotes an image recording memory card. A battery 55 supplies power to each unit of the imaging apparatus. The memory card 54 and the battery 55 can be inserted and removed from a not-shown lid.

  A release button 56 is arranged on the upper surface of the imaging apparatus 100, and a shooting preparation operation, that is, a focusing operation and a photometry operation are performed by pushing the first step (hereinafter referred to as switch S1ON). The photographing exposure operation is performed by (hereinafter referred to as switch S2ON). A main switch 57 is a switch for switching the imaging apparatus between an operating state and a non-operating state. When switched to the operating state by the main switch 57, the lens barrier (not shown) is opened and the operation of each part is started. When the main switch 57 is switched to the non-operating state, the lens barrier (not shown) is closed and ends the operation of each unit.

  On the back surface of the imaging apparatus 100, an image display unit 58 that is configured by an LCD, an organic EL, or the like and displays an image, other character information, or the like is disposed. Although not shown, a zoom button for zooming up and down, a playback button for playing back a captured image, a menu button for displaying various menus on the image display unit 58, and a desired function are selected from the display. An operation member such as a selection button is arranged.

  Although not shown, each part is connected between these main constituent units and a circuit board on which various electronic components are mounted is arranged to drive and control each main constituent unit. Yes. Similarly, although not shown, an external input / output terminal, a strap attaching portion, a tripod seat, and the like are provided.

  In the present embodiment, description is made using a bending imaging optical system capable of zooming. However, an imaging apparatus including an imaging optical system in which the optical axis is not bent may be used.

  Hereinafter, an image sensor initial position determination method and an optical element initial position determination method according to the present embodiment will be described.

(First embodiment)
In the first embodiment, an image sensor initial position determination method of an image pickup apparatus that performs camera shake correction by moving the image sensor will be described.

  FIG. 2 is a block diagram illustrating an overview of the imaging apparatus 100 according to the first embodiment.

  As shown in the figure, the imaging optical system 40 in the lens barrel 50 is configured to move a predetermined lens group by the first motor 20 and the second motor 21 and is subjected to zooming and focus adjustment. . Further, in the lens barrel 50, two actuators 61 for moving the image sensor 6 in a direction to cancel the image movement in the yaw direction and the pitch direction shown in FIG. The image sensor 6 is moved by the first drive actuator 61P and the second drive actuator 61Y. Note that the independent first and second drive actuators 61P and 61Y constituting the actuator 61 do not have to match the pitch direction and the yaw direction, and the image is taken in an arbitrary direction by combining the two actuators. What is necessary is just to be able to move an element.

  In the present embodiment, the first drive actuator 61P and the second drive actuator 61Y that move the image sensor 6 are stepping motors that can control the rotation angle in an open loop by a predetermined signal input. Yes.

  Further, a sensor 62 is provided for detecting the moving position of the image sensor 6 by the actuator 61. The position reference in the pitch direction is detected by the pitch direction reference sensor 62P, and the position reference in the yaw direction is detected by the yaw direction reference sensor 62Y.

  The actuator 61 is driven by a driver 63 controlled by the control unit 30. The first motor 20 and the second motor 21 are also driven by drivers 22 and 23 controlled by the control unit 30, respectively.

  A shake detection sensor 64 that detects the shake detects the shake of the lens barrel 50. Specifically, the shake detection sensor 64P detects an angular velocity in the pitch direction (specifically, an inertial angular velocity (ground angular velocity)), and the shake detection sensor 64Y detects an angular velocity in the yaw direction.

  The signals from the shake detection sensors 64P and 64Y are amplified and filtered by the shake detection circuit 65, detected as a signal indicating “shake”, and input to the control unit 30 constituted by, for example, a microcomputer. It has become.

  In the control unit 30, a predetermined software program stored in the ROM 81 is executed using a RAM (not shown) as a work area, and functions of the respective units are executed. For example, the control output unit 35 obtains the current angle in the pitch direction and the yaw direction based on the signal from the shake detection circuit 65, and obtains an output value that reduces the difference between the current angle and the target angle. That is, a control command value for driving the image pickup device 6 to move in the plane is generated so as to suppress the shake detected by the shake detection circuit 65. The control output unit 35 outputs the generated control command value to the driver 63.

  The driver 63 drives the first drive actuator 61P and the second drive actuator 61Y based on the control command value. Thereby, the image sensor 6 is displaced in a plane orthogonal to the optical axis, and the camera shake is corrected.

  The EEPROM 82 is storage means for storing adjustment data related to control of camera shake correction in addition to individual data such as a zoom position at the time of zooming of the image pickup optical system 40 and an infinite focus position of the focus lens. In the present embodiment, in the EEPROM 82, focusing lens position data necessary at the time of shooting, and adjustment data related to camera shake correction control, which will be described later, “image movement The data of “absent position” is stored.

  The external communication unit 83 is connected to an external device such as a personal computer (PC) and can communicate with each other, and can send an image obtained by the imaging apparatus 100 to the PC. In the PC, the “position without image movement” by scaling on the image sensor 6 can be obtained from the image by calculation or the like, sent to the image pickup apparatus 100, and stored in the EEPROM 82.

  The imaging apparatus 100 is provided with a signal processing unit 71, an A / D conversion unit 72, an image processing unit 73, and an image memory 74 as processing units that handle images obtained by the imaging element 6. The image of the analog signal acquired by the image sensor 6 is A / D converted by the A / D converter 72 via the signal processor 71 and subjected to predetermined image processing by the image processor 73, and then temporarily stored in the image memory 74. Stored. The image stored in the image memory 74 is recorded on the memory card 54 as a recording image, or displayed on the image display unit 58 as a live view display image by performing a desired process.

  An operation switch group 150 such as a cross key button, a zoom operation button, a mode selection dial, and a mode setting button group is connected to the control unit 30, and the imaging apparatus 100 is operated based on the operation by a user operation. ing.

  FIG. 3 is a cross-sectional view showing an example of the lens barrel 50. This figure is a cross-sectional view of a surface including the optical axis OA before bending and the optical axis OB after bending.

  In the figure, reference numeral 1 denotes a first lens group. The first lens group 1 is a prism 11 that is a reflection member that bends the optical axis OA in a substantially right angle direction with a lens 11 that is arranged toward the subject with an optical axis of OA. 12 and a lens 13 arranged with the optical axis OB bent by the prism 12 as an optical axis. The first lens group 1 is a lens group fixed to the main body 10.

  Reference numeral 2 denotes a second lens group, which is incorporated in the second lens group frame 2k. The second lens group 2 is a lens group that moves integrally with the second lens group lens frame 2k during zooming (hereinafter also referred to as zooming).

  Reference numeral 3 denotes a third lens group, which is fixed to the main body 10. The third lens group 3 is a lens group that does not move.

  S is a unit having at least one of an aperture and a shutter. This unit S is fixed to the main body 10.

  Reference numeral 4 denotes a fourth lens group, which is incorporated in the fourth lens group frame 4k. The fourth lens group is a lens group that moves integrally with the fourth lens group lens frame 4k at the time of zooming, and also moves alone to perform focus adjustment (hereinafter also referred to as focusing).

  The second lens group 2 and the fourth lens group 4 are located far away from the third lens group 3 at a wide angle, and move in a direction approaching the third lens group 3 with zooming to the long focal point side. To do.

  Reference numeral 90 denotes an image sensor moving mechanism, which is assembled on a base plate 91 fixed to the main body 10. The image sensor moving mechanism 90 can move the image sensor in a plane orthogonal to the optical axis OB, and the movement is corrected by this movement. A CCD (Charge Coupled Device) type image sensor, a CMOS (Complementary Metal-Oxide Semiconductor) type image sensor, or the like is used as the imaging device. An infrared light cut filter is disposed in front of the image sensor.

  As shown in the figure, a flexible printed circuit board FPC that inputs and outputs power and signals is connected to the image sensor moving mechanism 90 with a slack.

  The imaging optical system is not limited to this, and any imaging optical system may be used as long as it can be changed in magnification.

  FIG. 4 is a perspective view showing an example of the image sensor moving mechanism 90. FIG. 5 is a front view of the image sensor moving mechanism 90 shown in FIG.

  The image sensor moving mechanism 90 includes an image sensor 6, a pitch direction reference sensor 62P (photo interrupter PIp in this example), a yaw direction reference sensor 62Y (photo interrupter PIy in this example), a first drive actuator ( In this example, a stepping motor 61P and a second drive actuator (in this example, a stepping motor) 61Y are provided. The position from which the position reference signal is obtained by the pitch direction reference sensor 62P and the yaw direction reference sensor 62Y is used as a control reference position.

  The imaging element moving mechanism 90 is provided with a P-direction moving plate 93 that is guided by two guide shafts 92a and 92b fixed to the base plate 91 and is movable in the direction of the arrow P shown in the drawing. The P-direction moving plate 93 is integrally formed with an arm portion 93m and a PI shielding plate 93f. The arm portion 93m is engaged with a nut that is screwed into a lead screw that is rotated by a stepping motor 61P that is a first drive actuator. Thereby, the P-direction moving plate 93 is moved in the direction of the arrow P by the rotation of the stepping motor 61P. The PI shielding plate 93f is formed so as to pass between the light projecting and receiving portions of the photo interrupter PIp fixed to the base plate 91.

  Two guide shafts 95 a and 95 b are fixed to the P-direction moving plate 93. A Y-direction moving plate 96 is provided which is guided by the guide shafts 92a and 92b and is movable in the direction of the arrow Y shown in the figure. Similarly, although not shown in the drawings, the Y-direction moving plate 96 is integrally formed with an arm portion and a PI shielding plate. The arm portion is engaged with a nut that is screwed into a lead screw that is rotated by a stepping motor 61Y that is a second drive actuator. Thereby, the Y-direction moving plate 96 is moved in the arrow Y direction by the rotation of the stepping motor 61Y. A PI shielding plate (not shown) is formed so as to pass between the light projecting and receiving portions of the photo interrupter PIy fixed to the base plate 91.

  The Y-direction moving plate 96 is provided with the image sensor 6 and an infrared light cut filter.

  Thereby, by driving the stepping motors 61P and 61Y, the Y-direction moving plate 96, that is, the image pickup device 6 can be moved in a plane perpendicular to the optical axis OB of the image pickup optical system.

  With the output change position of the photo interrupter PIp due to the movement of the PI shielding plate 93f as the control reference position, the movement position of the P-direction moving plate 93 can be known by the rotation control of the stepping motor 61P. Similarly, the movement position of the Y-direction moving plate 96 can be known by the rotation control of the stepping motor 61Y with the output change position of the photo interrupter PIy due to the movement of the PI shield plate (not shown) as the control reference position. Thereby, the current position of the image sensor 6 can be known.

  FIG. 6 is a schematic diagram showing an outline of an apparatus for obtaining “a position without image movement” by zooming.

  The apparatus shown in the figure includes an imaging apparatus 100, a connection terminal 150 connected to an external communication unit 83 (see FIG. 2) of the imaging apparatus, and a cable 160 that connects the connection terminal and a personal computer (PC) 200. And a monitor 300 that displays a subject imaged by the imaging apparatus 100.

  The chart displayed on the monitor 300 is picked up by the image pickup apparatus 100, and the image data of the chart is transmitted to the personal computer (PC) 200 via the external communication unit, the connection terminal 150, and the cable 160. Based on the transmitted image data, the PC 200 uses a predetermined program to obtain a “position where the image does not move” by scaling, and the data regarding this position is obtained via the cable 160, the connection terminal 150, and the external communication unit. Thus, the image data is transmitted to the image pickup apparatus 100 and stored in the EEPROM in the image pickup apparatus 100.

  The apparatus shown in the figure is preferably arranged in a dark place, and the monitor 300 is preferably installed so as to cover the angle of view at the telephoto end of the imaging optical system mounted on the imaging apparatus 100.

  Hereinafter, in the manufacturing process, the method shown in FIG. 7 and FIG. 8 is used to determine the “position without image movement” (hereinafter referred to as “position without image movement”) by zooming using the apparatus shown in FIG. I will explain.

  FIG. 7 is a flowchart showing a procedure for obtaining “a position without image movement” using the apparatus shown in FIG. 6. FIG. 8 is a schematic diagram showing how to obtain “position without image movement”. On the monitor 300 (see FIG. 6), one light spot is displayed at a position away from the center.

  In the flowchart shown in FIG. 7, first, the image sensor moving mechanism is moved to a predetermined position and stopped (step S101). Specifically, for example, the P-direction moving plate 93 and the Y-direction moving plate 96 shown in FIG. 5 are stopped at the control reference position that is the output change position of the photo interrupters PIy and PIp. The predetermined position to be stopped is not limited to this, and may be a position where the stepping motor is driven by a predetermined number of steps from the control reference position.

Next, the imaging optical system is moved to the telephoto end (step S102), the monitor display screen is imaged, and the first image is captured (step S103). Image G ₁ of the first, as shown in FIG. 8 (a), are those light spots L ₁ that is displayed on the monitor is imaged, it is captured is sent to the PC 200.

Next, the imaging optical system is moved to the wide-angle end (step S104), the monitor display screen is imaged again, and the second image is captured (step S105). The second image G ₂ is, as shown in FIG. 8 (b), although on the monitor is obtained by imaging the light spot displayed on the same position, the angle of view changes due to zooming, different positions L _The image is picked up at the position ₁ ', transmitted to the PC 200, and taken in.

  Thereafter, the PC 200 obtains a “position where there is no movement of the image” from the captured first image and second image (step S106).

The “position without image movement” is on the extension line connecting the light spots L ₁ and L ₁ ′. Specifically, as shown in FIG. 8C, from the distance D between the light spots L ₁ and L ₁ ′ on the image sensor and the focal length values at the telephoto end and the wide-angle end, the light spot L ₁ ′ and A distance R from “a position without image movement” is obtained, and coordinates of “a position without image movement” shown in FIG.

  Next, a shift amount for making the center C of the effective pixel of the image sensor on the image sensor moving mechanism stopped at a predetermined position (control reference position) coincide with the “position without image movement” O is obtained ( Step S107). Thereafter, the shift amount is stored in the storage means (step S108). Specifically, the obtained shift amount is transmitted from the PC 200 to the imaging device 100 and stored in the EEPROM in the imaging device 100. More specifically, the shift amount is preferably stored as the rotation direction and rotation angle of the stepping motors 61P and 61Y from the control reference position.

  This “position without image movement” substantially coincides with the position of the optical axis of the imaging optical system, and by moving the imaging element from the predetermined position by the above-mentioned shift amount, the effective pixel of the imaging element is obtained. Can be made substantially coincident with the optical axis. In other words, the state where the center of the effective pixel of the image sensor is moved to the “position where there is no movement of the image” is set as the initial position at the time of shooting. The direction can have the same margin for movement.

  By adopting the method for determining the initial position of the image sensor as described above, the image sensor movement mechanism does not require an extra movement range that is not used at the time of shooting, thereby reducing the size of the camera shake correction mechanism and the size of the lens barrel. It becomes possible. Furthermore, it is possible to provide an image pickup apparatus in which there is no deviation between the center of image change due to zooming and the center of effective pixels of the image sensor.

  FIG. 9 is a flowchart showing an outline of the operation at the time of shooting of the image pickup apparatus in which the initial position of the image pickup element determined as described above is stored. Hereinafter, it demonstrates according to a flow.

  As shown in the figure, when the image pickup apparatus is set to the shooting mode, first, the image pickup element is moved to a position where the effective pixel center of the image pickup element is “a position where there is no image movement” (step S201). This “position without image movement” is a position determined by the method described with reference to FIGS. With this operation, it is possible to secure the same amount of movement margin in any direction against blurring at the time of shooting that cannot be predicted before shooting. This position is the initial position of the image sensor in the shooting mode.

  After this operation, it is determined whether or not the main switch is turned on (step S202). If the main switch is turned on (step S202; Yes), the switch S1 that is the first push of the release button is turned on. It is determined whether it has been performed (step S203). If the switch S1 is not turned on (step S203; No), the process returns to step S202.

  When the switch S1 is turned on (step S203; Yes), a shooting preparation operation is performed (step S204). The shooting preparation operation is, for example, a focusing operation or a photometric operation. After completion of the shooting preparation operation, it is determined again whether the switch S1 is turned on (step S205). If the switch S1 is not turned on (step S203; No), the process returns to step S202. When the switch S1 is turned on (step S205; Yes), it waits for the switch S2, which is the second push of the release button, to be turned on (step S206). At this stage, if the switch S1 is not turned on (turned off) (step S205; No), the process returns to step S202.

  When the switch S2 is turned on (step S206; Yes), shooting is performed while correcting camera shake (step S207), and the shot image is recorded on a memory card that is a recording medium (step S208). Thus, the shooting and recording of one image is completed, and the process returns to step S201.

  In addition, in the loop of step S202 and step S203, when the main switch is turned off (step S202; No), the process is ended.

  The above is the outline of the operation at the time of shooting of the imaging apparatus in which the initial position of the imaging element is stored.

  FIG. 10 is a schematic diagram illustrating another example of how to obtain “position without image movement”. FIG. 4A is a diagram showing a first image obtained by moving the imaging optical system to the telephoto end and capturing the display screen of the monitor, and FIG. 4B is a diagram showing the moving of the imaging optical system to the wide angle end. FIG. 4B is a diagram showing the second image obtained by capturing the display screen of the same monitor, and FIG. 8C is a concept for obtaining “position without image movement” from the first image and the second image. FIG.

  In the example shown in the figure, photographing is performed by displaying two light spots at different positions on the monitor, and “position without moving image” is obtained.

First, by moving the imaging optical system to the telephoto end, shown in FIG. 6 (a), taking a first image G _1. The first image _{G 1} obtained at this time, as shown in the figure, the two light spots _{L 1} and _{L 2} is imaged, is captured is sent to the PC 200.

Then, by moving the imaging optical system at the wide angle end, capturing the display screen of the monitor again, capturing images G ₂ of the second. The second image G ₂ is, although on the monitor is obtained by imaging the light spot displayed on the same position, the angle of view changes due to the zooming, as shown in FIG. (B), different positions L Images are taken at positions ₁ ′ and L ₂ ′, transmitted to the PC 200, and taken in.

Thereafter, from the first image G ₁ taken in the PC200 second image G _2, obtaining the "movement without the position of the image" in the manner shown in FIG. (C).

The “position without image movement” is an intersection of an extension line connecting the light spots L ₁ and L ₁ ′ and an extension line connecting the light spots L ₂ and L ₂ ′. Find the coordinates of "position".

  By such a method, the coordinates of “position where there is no movement of the image” may be obtained. As another method, the light spot on the monitor is photographed by zooming between exposures, and the coordinates of the “position without moving the image” are obtained from the continuous line of the obtained light spot in the same way as described above. May be.

  Further, the above-described method may be repeated a plurality of times, and the average value of the obtained coordinates may be set as “a position without image movement”.

(Second Embodiment)
In the second embodiment, an optical element initial position determination method of an imaging apparatus that performs camera shake correction by moving an optical element will be described.

  FIG. 11 is a block diagram illustrating an overview of the imaging apparatus 100 according to the second embodiment. In the block diagram shown in the figure, only the parts different from those shown in FIG. 2 will be described.

  As shown in the figure, the imaging optical system 40 in the lens barrel 50 is configured to move a predetermined lens group by the first motor 20 and the second motor 21 and is subjected to zooming and focus adjustment. . Further, in the lens barrel 50, two optical elements that move at least one optical element in the imaging optical system in a direction orthogonal to the optical axis in a direction that cancels the image movement in the yaw direction and the pitch direction shown in FIG. An actuator 61 is provided. The optical element is moved by the first drive actuator 61P and the second drive actuator 61Y. Note that the independent first and second drive actuators 61P and 61Y constituting the actuator 61 do not have to match the pitch direction and the yaw direction, and the image is taken in an arbitrary direction by combining the two actuators. What is necessary is just to be able to move an element.

  A sensor 62 for detecting the movement position of the optical element by the actuator 61 is provided. The position reference in the pitch direction is detected by the pitch direction reference sensor 62P, and the position reference in the yaw direction is detected by the yaw direction reference sensor 62Y. The position from which the position reference signal is obtained by the pitch direction reference sensor 62P and the yaw direction reference sensor 62Y is used as a control reference position.

  In the control unit 30, a predetermined software program stored in the ROM 81 is executed using a RAM (not shown) as a work area, and functions of the respective units are executed. For example, a control command value for in-plane displacement driving of the optical element is generated so as to cancel the movement of the image on the image sensor due to the shake detected by the shake detection circuit 65. The control output unit 35 outputs the generated control command value to the driver 63.

  The driver 63 drives the first drive actuator 61P and the second drive actuator 61Y based on the control command value. Thereby, the optical element is displaced in a plane orthogonal to the optical axis, and the camera shake is corrected.

  The EEPROM 82 is storage means for storing adjustment data related to control of camera shake correction in addition to individual data such as a zoom position at the time of zooming of the image pickup optical system 40 and an infinite focus position of the focus lens. In the present embodiment, in the EEPROM 82, focusing lens position data necessary at the time of photographing, as well as adjustment data relating to control of camera shake correction, an effective pixel center of the image sensor 6 described later is displayed as an “image by zooming”. The data of the position of the optical element that is “position without movement” is stored.

  The external communication unit 83 is connected to an external device such as a personal computer (PC) and can communicate with each other, and can send an image obtained by the imaging apparatus 100 to the PC. In the PC, the position of the optical element where the effective pixel center of the image sensor 6 becomes the “position without image movement” due to magnification is calculated from the image, sent to the image capturing apparatus 100, and stored in the EEPROM 82. It can be made to.

  FIG. 12 is a cross-sectional view showing an example of a lens barrel 50 according to the second embodiment. This figure is a cross-sectional view of a surface including the optical axis OA before bending and the optical axis OB after bending. Only the parts of the lens barrel shown in FIG. 3 different from those shown in FIG. 3 will be described.

  The third lens group 3 shown in the figure is held by an optical element moving mechanism 190, and is configured to be movable in a plane perpendicular to the optical axis OB by the optical element moving mechanism 190. That is, the third lens group 3 is a lens group that does not move in the optical axis direction but moves in a plane perpendicular to the optical axis OB and performs camera shake correction.

  The optical element moving mechanism 190 is the same as the mechanism shown in FIGS. 4 and 5, and holds the third lens group in place of the imaging element shown in FIGS. 4 and 5.

  As shown in the drawing, a flexible printed circuit board FPC that inputs and outputs power and signals is connected to the optical element moving mechanism 190 with slack.

  In addition, the image sensor 6 is fixed to the main body 10.

  The imaging optical system is not limited to this, and any imaging optical system may be used as long as it can be changed in magnification.

  In the second embodiment, the outline of the apparatus for the initial position of the optical element of the image pickup apparatus that performs camera shake correction by moving the optical element is the same as that shown in FIG.

  FIG. 13 shows the position of the optical element (in this example, the third lens group) at which the effective pixel center of the image sensor becomes the “position without image movement” due to zooming, using the apparatus shown in FIG. It is a flowchart which shows a procedure. On the monitor 300 (see FIG. 6), one light spot is displayed at a position away from the center.

  In the flowchart shown in FIG. 13, first, the optical element moving mechanism is moved to a predetermined position (for example, control reference position) and stopped (step S301).

Next, the imaging optical system is moved to the telephoto end (step S302), the display screen of the monitor is imaged, and the first image is captured (step S303). Image G ₁ of the first, as shown in FIG. 8 (a), are those light spots L ₁ that is displayed on the monitor is imaged, it is captured is sent to the PC 200.

Next, the imaging optical system is moved to the wide-angle end (step S304), the monitor display screen is imaged again, and this second image is captured (step S305). The second image G ₂ is, as shown in FIG. 8 (b), although on the monitor is obtained by imaging the light spot displayed on the same position, the angle of view changes due to zooming, different positions L _The image is picked up at the position ₁ ', transmitted to the PC 200, and taken in.

  Thereafter, the PC 200 obtains a “position where there is no movement of the image” from the captured first image and second image (step S306).

The “position without image movement” is on the extension line connecting the light spots L ₁ and L ₁ ′. Specifically, as shown in FIG. 8C, from the distance D between the light spots L ₁ and L ₁ ′ on the image sensor and the focal length values at the telephoto end and the wide-angle end, the light spot L ₁ ′ and A distance R from “a position without image movement” is obtained, and coordinates of “a position without image movement” shown in FIG.

  Next, from “the position where there is no image movement”, the shift amount from the predetermined position (control reference position) of the optical element for eliminating the image movement due to zooming at the center C of the effective pixel of the image sensor is calculated. (Step S307). Thereafter, the shift amount is stored in the storage means (step S308). Specifically, the obtained shift amount is transmitted from the PC 200 to the imaging device 100 and stored in the EEPROM in the imaging device 100. More specifically, the shift amount is preferably stored as the rotation direction and rotation angle of the stepping motors 61P and 61Y from the control reference position.

  That is, in the second embodiment, imaging is performed by moving the optical element (in this example, the third lens group) from a predetermined position by the above-described shift amount, so that “position without image movement” due to zooming. The effective pixel centers of the elements can be matched, and this state is the initial position of the optical element at the time of photographing.

  FIG. 14 is a flowchart showing an outline of the operation at the time of shooting of the imaging apparatus in which the initial position of the optical element determined as described above is stored. Hereinafter, it demonstrates according to a flow.

  As shown in the figure, when the imaging apparatus is set to the imaging mode, first, the optical element is moved to a position where the effective pixel center of the imaging element is a “position where there is no image movement” (step S401). This “position without image movement” is a position determined by the method described in FIG. This position is the initial position of the optical element (in this example, the third lens group) in the shooting mode.

  After this operation, it is determined whether the main switch is turned on (step S402). If the main switch is turned on (step S402; Yes), the switch S1 that is the first push of the release button is turned on. It is determined whether it has been performed (step S403). If the switch S1 is not turned on (step S403; No), the process returns to step S402.

  When the switch S1 is turned on (step S403; Yes), a shooting preparation operation is performed (step S404). The shooting preparation operation is, for example, a focusing operation or a photometric operation. After completion of the shooting preparation operation, it is determined again whether the switch S1 is turned on (step S405). If the switch S1 is not turned on (step S403; No), the process returns to step S402. When the switch S1 is turned on (step S405; Yes), it waits for the switch S2, which is the second push of the release button, to be turned on (step S406). If the switch S1 is not turned on (turned off) at this stage (step S405; No), the process returns to step S402.

  When the switch S2 is turned on (step S406; Yes), shooting is performed while correcting camera shake (step S407), and the shot image is recorded on a memory card as a recording medium (step S408). Thus, the shooting and recording of one image is completed, and the process returns to step S401.

  In addition, in the loop of step S402 and step S403, when the main switch is turned off (step S402; No), the process is terminated.

  The above is the outline of the operation at the time of shooting of the imaging apparatus in which the initial position of the optical element is stored.

  In the second embodiment, an optical element that uses a lens is described as an example of an optical element that performs camera shake correction. However, the present invention is not limited to this, and an optical element that uses a variable apex angle prism as an optical element. Is also applicable. In the case of using this variable apex angle prism, the “movement of the optical element” is to move at least one surface of the optical element, and the “shift amount” from the predetermined position is the movement amount of the surface to be moved. This is a shift amount from a predetermined position.

  It should be noted that the “position without image movement” by zooming used in the above first and second embodiments does not mean that the image is strictly stationary, but moves when the image is viewed. It may be a position where it can be regarded as not. Further, the imaging element moving mechanism and the optical element moving mechanism have been described as being moved by the stepping motor. However, the present invention is not limited to this, and a voice coil motor or the like may be used. In addition, although the EEPROM is used as the storage means for storing the shift amount, a nonvolatile memory may be used, and a flash memory or the like may be used.

It is a figure which shows an example of the internal arrangement | positioning of the main structural unit of the imaging device which concerns on this Embodiment. It is a block diagram which shows the outline | summary of the imaging device which concerns on 1st Embodiment. It is sectional drawing which shows an example of a lens barrel. It is a perspective view which shows an example of an image pick-up element moving mechanism. It is a front view of the image pick-up element moving mechanism shown in FIG. It is a schematic diagram which shows the apparatus outline | summary for calculating | requiring "the position without the movement of an image" by scaling. It is a flowchart which shows the procedure which calculates | requires "the position without the movement of an image" using the apparatus shown in FIG. It is a schematic diagram which shows how to obtain | require "the position without the movement of an image." It is a flowchart which shows the operation | movement outline at the time of imaging | photography of the image pick-up device memorize | stored in the determined initial position of the image pick-up element. It is a schematic diagram which shows the other example of how to obtain | require "the position without the movement of an image." It is a block diagram which shows the outline | summary of the imaging device which concerns on 2nd Embodiment. It is sectional drawing which shows an example of the lens barrel which concerns on 2nd Embodiment. FIG. 7 is a flowchart showing a procedure for obtaining the position of an optical element at which the effective pixel center of the image sensor becomes a “position without image movement” by zooming using the apparatus shown in FIG. 6. It is a flowchart which shows the operation | movement outline at the time of imaging | photography of the imaging device in which the determined initial position of the optical element was memorize | stored.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st lens group 2 2nd lens group 2k 2nd lens group frame 3 3rd lens group 4 4th lens group 4k 4th lens group frame 6 Imaging element 10 Main trunk 15, 16 Guide shaft 20 1st motor 21 Second motor 50 Lens barrel 61P First drive actuator 62Y Second drive actuator 91 Base plate 92a, 92b Guide shaft 93 P direction moving plate 95a, 95b Guide shaft 96 Y direction moving plate 90 Image sensor moving mechanism 100 Imaging device 190 Optical element moving mechanism 200 Personal computer 300 Monitor PIp, PIy Position detection unit

Claims (6)

An imaging optical system capable of zooming to guide subject light;
An image sensor that photoelectrically converts subject light guided by the imaging optical system;
An image sensor moving mechanism for moving the image sensor in a direction perpendicular to the optical axis of the imaging optical system;
An image pickup device initial position determination method of an image pickup apparatus that performs camera shake correction using the image pickup device moving mechanism.
Acquiring images at a plurality of different focal lengths within a variable magnification region of the imaging optical system in a state where the imaging element is stopped at a predetermined position;
Based on images obtained at a plurality of different focal lengths, obtaining a position where there is no movement of the image due to scaling on the image sensor;
A step of obtaining a shift amount from the predetermined position of the image sensor, wherein the obtained position on which the image does not move due to scaling on the image sensor is the effective pixel center of the image sensor;
Storing the shift amount in the storage means;
An image pickup device initial position determination method comprising: 2. The imaging element initial position determination method according to claim 1, wherein the plurality of focal lengths are a wide-angle end and a telephoto end of the imaging optical system. The image sensor initial position determination method according to claim 1, wherein the subject in the step of acquiring images at a plurality of focal lengths is a light spot. An imaging optical system capable of zooming to guide subject light;
An image sensor that photoelectrically converts subject light guided by the imaging optical system;
An optical element moving mechanism for moving the position of the image in a direction perpendicular to the optical axis by moving at least one optical element of the imaging optical system in the previous period;
And an optical element initial position determination method for an imaging apparatus that performs camera shake correction using the optical element moving mechanism.
A step of acquiring images at a plurality of different focal lengths within a variable magnification region of the imaging optical system in a state where the optical element is stopped at a predetermined position;
A step of obtaining a position where there is no movement of the image due to zooming based on images obtained at a plurality of different focal lengths;
Based on the obtained position where the image does not move due to magnification, the amount of shift of the optical element from the predetermined position is calculated so that the image does not move due to magnification at the center of the effective pixel of the image sensor. And a process of
Storing the shift amount in the storage means;
An optical element initial position determination method comprising: The optical element initial position determination method according to claim 4, wherein the plurality of focal lengths are a wide-angle end and a telephoto end. 6. The optical element initial position determining method according to claim 4, wherein the subject in the step of acquiring images at a plurality of focal lengths is a light spot.

Images