JP4564930B2 - Image stabilizer - Google Patents

Description

The present invention relates to a camera shake correction apparatus, and more particularly to a camera shake correction apparatus having an XY movable stage in which a movable part provided with an image sensor is movable in an XY direction with respect to a fixed part.

  In an imaging apparatus such as a video camera or a digital still camera, it has been studied to remove image blur due to a user's camera shake by correcting a physical optical axis or logical image processing in the image.

  Among such camera shake corrections, the physical optical axis correction includes an image sensor installed on a movable part of a movable stage movable on an XY plane perpendicular to the optical axis, and an image generated by camera shake. There is a technique for stabilizing the absolute position of the image sensor by moving the surface movement by an amount to be corrected. Here, when the movable part is made completely movable, rotation around the optical axis also occurs. Therefore, a technique for correcting camera shake by providing a coil spring that suppresses such rotation is known (for example, Patent Documents). 1).

  As another technique for suppressing rotation, a technique is also known in which a shaft is provided in each of XY directions and a movable portion is moved along the shaft (for example, Patent Document 2). However, in such a technique, although the rotation of the movable part is suppressed, the structure is complicated because it takes a two-stage configuration of a stage moving in the X direction and a stage moving in the Y direction on the stage. Increases cost and reduces reliability.

  A technique for controlling rotation around the optical axis using a voice coil motor is also known (for example, Patent Document 3), but the movable part is mechanically fixed to the fixed part by a tension spring. , Maintenance is required, and the elasticity of the springs hinders the linear and rotational driving of the movable part, resulting in a problem that power consumption cannot be reduced.

JP-A-10-254019 JP 2003-111449 A JP 2005-184122 A

The present invention has been made in view of the above-described problems of the conventional movable stage, and the object of the present invention is to provide only a magnetic force without a mechanical anti-rotation structure or an adsorption structure to a fixed portion. It is an object of the present invention to provide a camera shake correction apparatus having a new and improved XY movable stage capable of controlling the movable stage.

Shake correction apparatus according to an aspect of the present invention has been made to solve the above problems, the hand shake detecting unit for detecting the amount of hand-shake, a movable portion imaging element is provided, and a fixing portion supporting the movable portion, In at least one of the X direction and the Y direction in the XY plane perpendicular to the optical axis, the suction portion that attracts the movable portion to the fixed portion by magnetic force extends from the center of gravity of the movable portion in the one direction. A plurality of sensors that detect the movement amounts of two different points on the movable part that are not on a straight line in the same direction, and that are not on a straight line that extends in one direction from the center of gravity of the movable part in the one direction. An XY movable stage including a plurality of electromagnetic actuators that linearly control two different points on the movable part, and the movable to compensate for the camera shake amount from the camera shake amount of the camera shake detection unit. A rotation operation amount that is a value obtained by converting an angle at which the movable portion should be converted into a linear movement amount of the movable portion and a linear operation amount that is a value that the movable portion should linearly move to compensate for the amount of camera shake, Based on the amount of rotation calculated from the difference between the amount of rotation operation and the amount of movement detected by the plurality of sensors, the plurality of electromagnetic actuators are used to control the rotation of the movable part on the XY plane, and the linear operation A control signal generator that linearly controls the movable part in the one direction using at least one of the plurality of electromagnetic actuators based on the amount and the amount of movement detected by at least one of the plurality of sensors, The fixed portion includes the sensor, a yoke having a cross-section of a “U” shape, and a magnet provided with a gap in the yoke, and the movable portion includes an adsorption plate and the yoke. And magnet gap The yoke, the magnet, and the coil constitute the electromagnetic actuator, the electromagnetic actuator and the suction plate constitute the suction portion, and the width of the suction plate is It is characterized by being formed smaller than the width of the yoke in both the X and Y directions.

Preferably, the plurality of electromagnetic actuators of the XY movable stage are arranged to face each other with the center of gravity of the movable part interposed therebetween .

  Preferably, the plurality of electromagnetic actuators of the XY movable stage are arranged diagonally with respect to the movable part.

  Preferably, the plurality of sensors of the XY movable stage are arranged to face each other with the center of gravity of the movable part interposed therebetween.

  Preferably, the plurality of sensors of the XY movable stage are arranged diagonally with respect to the movable part.

  As described above, according to the present invention, the movable stage can be controlled only by the magnetic force, and no mechanical anti-rotation structure or adsorption structure to the fixed part is required. , Wasteful power consumption due to the suction force of the mechanical suction structure can be reduced.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  For correction of the physical optical axis in an imaging apparatus such as a video camera or a digital still camera, an image sensor is installed on a movable part of a movable stage movable on an XY plane perpendicular to the optical axis, and the movable part is moved by camera shake. There is a technique for stabilizing the absolute position of the image sensor by moving the generated image plane movement by an amount to be corrected.

  When moving the movable part in the XY direction on the fixed part, (1) When the movable part becomes completely movable, the movable part rotates around the optical axis, and the image by the image sensor also rotates. (2) There is a problem that the movable part is detached from the fixed part unless the movable part and the fixed part are fixed.

  For (1) rotation around the optical axis, a solution means is provided in which a coil spring for suppressing the rotation is provided, or a shaft is provided in each of XY directions, and the movable stage is moved along the shaft.

  FIG. 13 is an explanatory diagram showing the movable direction of the movable part when the shaft is provided on the movable stage. In such a movable stage, the X stage 14 is moved only in the X direction with respect to the fixed portion 10 by the X direction shaft 12, and the Y stage 18 is moved only in the Y direction by the Y direction shaft 16 provided on the X stage 14. To do. However, although this technique suppresses the rotation of the movable stage, the structure becomes complicated. In particular, in the method along the shaft, unnecessary vibration is generated due to rattling and bending between the two stages, and the movable stage is moved. This interferes with the control of the department.

  Also, for the above (2) separation of the fixed part, a technique is known in which the movable stage is mechanically fixed to the fixed part by a tension spring.

  FIG. 14 is an explanatory view showing the movable direction when a tension spring is provided on the movable stage. In such a movable stage, only one movable part 52 is provided on the fixed part 50, and the movement direction is not restricted by the shaft as described with reference to FIG. 13, so that it can move freely in the XY directions. It is. Further, the movable portion 52 is locked to the fixed portion 50 by the suction force by the tension spring 54. However, in this configuration, maintenance around the tension spring 54 is required, and the elasticity of the spring prevents the movable stage from being linearly driven in the X direction or Y direction, thereby consuming useless power.

  For example, when the suction force f is acting in the Z direction by the mechanical spring, when the movable portion 52 is driven in the XY plane direction, a force of f × sin (θ) is applied in the direction opposite to the drive direction (the spring force). The inclination from the Z-axis is assumed to be θ), impeding the driving of the movable part.

  In the embodiment of the present invention, (1) the rotation around the optical axis is suppressed or controlled by providing at least two sensors and two electromagnetic actuators, and (2) by the magnetic force of the suction portion based on a simple configuration, Avoid moving parts away. In addition, linear control on the XY plane of the movable part is also performed using two sensors and two electromagnetic actuators. Under such a configuration, a mechanical structure for preventing rotation and adsorbing to the fixed portion is not required, so that maintenance-free, low power consumption, low cost, and miniaturization can be achieved.

  Hereinafter, an XY movable stage according to an embodiment of the present invention will be described in detail.

(First embodiment: XY movable stage)
FIG. 1 is a perspective view showing an appearance of an XY movable stage in the first embodiment. The XY movable stage includes a movable part 100, a fixed part 110, and an image sensor 120.

  The movable unit 100 is provided with an image sensor 120 and freely moves within an mechanically limited range on an XY plane perpendicular to the optical axis (Z-axis direction in the drawing). In this embodiment, since there is no mechanical fixing means, when there is no attractive force due to magnetic force, rotation not only in the XY linear direction but also around the Z axis is possible.

  The fixed unit 110 is fixed to the imaging device side on which the XY movable stage is mounted, and supports the movable unit 100. Therefore, the fixing unit 110 is directly affected by hand shake by the user.

  The image sensor 120 is formed of a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), and may include a face plate, an LPF (Low Pass Filter), or the like. An image picked up by the image pickup device 120 is taken into the image pickup apparatus.

  FIG. 2 is an assembly diagram showing a detailed portion of the XY movable stage. The fixed portion 110 is provided with a sensor 140, a magnet 150, a fixed side yoke (fixed side back yoke) 152, and a ball bearing 154, and the movable portion 100 has a coil 160 and a movable side yoke. 162.

  The sensor 140 is composed of two or more movement amount detection sensors, such as a photo interrupt using light reflection, and detects the movement amounts of two different points on the movable unit 100 in the same direction. Such two points can be provided in at least one direction of XY on the XY plane other than on a straight line extending in one direction from the center of gravity of the movable unit 100 on the XY plane, for example, around the diagonal of the movable unit 100. .

  FIG. 3 is a plan view abstractly showing the XY movable stage showing the position of the sensor 140. Here, the two sensors 140A, 140B, 140C, 140D provided in the XY direction are points 190A, 190B, not on the straight lines 182, 184 respectively extending from the center of gravity 180 on the XY plane of the movable unit 100 in the XY direction. The amount of movement is detected by measuring the distances from the sensors 140A, 140B, 140C, 140D to the points 190A, 190B, 190C, 190D in the directions corresponding to 190C, 190D, respectively.

  Returning to FIG. 2, the magnet 150 is made of a permanent magnet, an electromagnet, or the like, and includes a fixed yoke 152 and a movable yoke 162, which will be described later, in the Z direction between the movable portion 100 and the fixed portion 110. Generate magnetic force. The magnet 150 may be composed of two bodies whose magnetic directions are opposite in the Z direction.

  The fixed side yoke 152 is provided below the magnet 150 and can be used as a part of the magnetic circuit when used together with the magnet 150.

  The ball bearings 154 are formed in a spherical shape and are provided on the fixed part 110 at least three. Since the height of the ball apex of the ball bearing 154 is adjusted to be the same, the movable unit 100 can freely move in the XY directions on the ball bearing 154. Further, the ball bearing 154 can restrict the adsorption of the movable part 100 to the fixed part 110 and can keep the distance between the movable part 100 and the fixed part 110 constant. In the present embodiment, four ball bearings 154 are provided in the XY movable stage.

  FIG. 4 is a cross-sectional view for explaining a support mechanism of the movable part 100 by the ball bearing 154. Here, the movable yoke 162 that also functions as an attracting part and the magnet 150 attract each other, and the ball bearing 154 serves to maintain the distance between the movable part 100 and the fixed part 110. Such a ball bearing 154 rolls in all directions on the XY plane and generates almost no friction.

  Further, the ball bearing 154 may be initialized so that the movable unit 100 is placed at the center of the movable range by applying the movable unit 100 to the vertical limit in the X direction and the vertical limit in the Y direction when driving the XY movable table.

  The coil 160 is formed on a plane perpendicular to the magnetic flux generated by the magnet 150. By passing a current through the coil 160, an electromagnetic force in the X or Y direction is generated, and a linear driving force corresponding to the amount of current can be obtained. Such a driving method may use the principle of VCM (Voice Coil Motor) used for positioning the head of the HDD.

  The movable yoke 162 is provided on the top of the coil 160 and can be used as a part of the magnetic circuit when used together with the fixed yoke 152 and the magnet 150.

  In this embodiment, an electromagnetic actuator is formed by the magnet 150, the fixed yoke 152, the coil 160, and the movable yoke 162, and the magnet 150 and the movable yoke 162 form an attracting portion. It is formed.

  The electromagnetic actuator formed in this way moves the movable part 100 in the X direction (positive and negative) or Y direction (positive) by the coil 160 and the magnetic circuit including the magnet 150, the fixed yoke 152, and the movable yoke 162. And negative). Further, the suction part can suck the movable part 100 to the fixed part 110 by the suction force, and can maintain the distance of the movable part 100 from the fixed part 110.

  FIG. 5 is an explanatory diagram for explaining the external appearance of the electromagnetic actuator 200. Here, (a) is a front view, (b) is a plan view, and (c) is a side view. In FIG. 5, the length of the linear portion divided into two in the longitudinal direction of the coil 160 is formed larger than the width of the magnet 150 and the fixed yoke 152 by the movable range of the movable portion 100, for example, 1 mm. The width in the hand direction is formed smaller than the width of the magnet 150 by the movable range of the movable part 100. This is because, within the movable range, the relationship between the magnetic flux by the magnet 150 and the current flowing through the coil 160 are made equal within a possible range to generate a uniform electromagnetic force.

  Further, the movable yoke 162 is formed to be smaller than the width of the magnet 150 and the fixed yoke 152 by the movable range in both XY directions. This is because if the movable yoke 162 is removed from the movable range, a suction force component in the X direction or the Y direction, not the Z direction (optical axis direction), is generated, which hinders the driving force. Since the movable yoke 162 is within the movable range, the suction force in the X direction and the Y direction of the movable yoke 162 can be ignored.

  The electromagnetic actuator 200 is composed of two or more for each XY direction, and linearly controls two different points on the movable part 100 in the same direction. Similar to the sensor 140, these two points are located on at least one direction of XY on the XY plane other than on a straight line extending in one direction from the center of gravity of the movable unit 100 on the XY plane, for example, around the diagonal of the movable unit 100 Can be provided.

  Referring again to FIG. 3, the electromagnetic actuators 200A, 200B, 200C, and 200D are not located on the straight lines 182 and 184 extending in the XY direction from the center of gravity 180 on the XY plane of the movable unit 100, and the sensors 140A and 140B. , 140C, 140D, the points 210A, 210B, 210C, 210D corresponding to the driving directions are driven. That is, the force progression vector by the electromagnetic actuator does not pass through the center of gravity 180.

  Accordingly, taking one pair of the sensor 140 and the electromagnetic actuator 200 as an example, the movement amount in the Y direction of an arbitrary point 190A of the movable part 100 is detected by the sensor 140A, and a desired rotation operation amount or linear operation amount and its Based on the detected movement amount, the current flowing through the coil 160 of the electromagnetic actuator 200A is controlled to move the point 210A corresponding to the point 190A in the Y direction.

  In the above description, a pair of the sensor 140A and the electromagnetic actuator 200A has been described. However, a pair of the sensor 140B and the electromagnetic actuator 200B is also provided in the Y direction, and the sensor 140C, the electromagnetic actuator 200C, the sensor 140D, and the electromagnetic wave are provided in the X direction. A pair with the actuator 200D is provided. However, when the rotation control is performed in any one of the XY directions, it is not necessary to control the rotation in the other direction. For example, the configuration of the sensor 140D and the electromagnetic actuator 200D can be omitted. At this time, the force travel vector of the electromagnetic actuator 200C remaining in the X direction may be arranged so as to pass through the center of gravity.

  Such a pair of electromagnetic actuators 200 in the XY direction, for example, the electromagnetic actuators 200A and 200B, has a symmetrical structure sandwiching the center of gravity 180, thereby simultaneously controlling the linear drive and the rotational drive of the movable part. be able to. In addition, the suction portion using the magnetic force of the electromagnetic actuator 200 generates a suction force between the movable portion and the fixed portion, and can prevent the movable portion 100 from being detached from the fixed portion 110. Under such a configuration, there is no need for a mechanical structure for preventing rotation and attracting to a fixed part, and it is possible to reduce power consumption and to be made compact.

(Drive control method)
Next, a drive control method for driving and controlling the movable unit 100 provided with the image sensor in the XY direction with respect to the fixed unit 110 using the XY movable stage will be described. As described above, the XY movable stage used here is provided at two different points on the movable part 100 that are not on a straight line extending in the one direction from the center of gravity of the movable part 100 in at least one direction of XY. Further, two sensors 140 and a plurality of electromagnetic actuators 200 that are arranged to face each other in the one direction and linearly control a part of the movable part 100 in the one direction are provided.

  FIG. 6 is a block diagram illustrating a schematic algorithm of the drive control method according to the first embodiment. Here, two pairs of sensors 140A and 140B and electromagnetic actuators 200A and 200B shown in FIG. 3 will be described.

First, in a control signal generation unit to be described later, a linear operation amount y that is an operation amount in the linear direction (Y direction in FIG. 3) is generated, and a closed loop is formed by a pair of each of the sensors 140A and 140B and the electromagnetic actuators 200A and 200B. Input to the control system. In each of the above control system, the linear operating signal y input, fed back each sensor 140A, 140B moving amount y _a of _subtracts y _b, respectively of the electromagnetic actuator 200A corresponding multiplied by the actuator-specific parameters , 200B is driven in the one direction.

  Here, Ca and Cb are phase compensations of the electromagnetic actuators 200A and 200B, and Ka and Kb are coefficients of gain amplifiers of the electromagnetic actuators 200A and 200B. Further, all values on the algorithm define one direction (for example, the positive direction of Y) as positive.

  FIG. 7 is a block diagram illustrating a schematic algorithm of another drive control method according to the first embodiment. In such a drive control method, in addition to the linear control on the XY plane described with reference to FIG. 6, rotation control with the Z-axis direction as the center of rotation is performed. Also here, the two pairs of the sensors 140A and 140B shown in FIG. 3 and the electromagnetic actuators 200A and 200B are controlled.

Together with the linear operation amount y, control the rotation operation amount _{y d} in the signal generator is generated, the rotational operation amount _{y d,} respectively each sensor 140A, and 140B, the electromagnetic actuator 200A, the closed loop control system by pairs of 200B Input with different signs. In each of the above control system, each of the electromagnetic actuator from the input rotational operation amount y _d, fed back each sensor 140A, 140B moving amount y _a of _the y _b is subtracted, corresponding multiplied by the actuator-specific parameters 200A and 200B are driven in the one direction.

  In each pair, linear control is performed in the opposite directions by the input rotational operation amount, and as a result, the movable unit 100 rotates. Therefore, the rotation operation amount is a value obtained by converting the angle to be rotated into a linear movement amount, and the angle and the drive amount have a non-linear relationship. The conversion between the angle and the linear movement amount may be performed by the control signal generation unit.

  Here, when the algorithm shown in FIG. 7 is used and the movable unit 100 is driven only in a straight line, the rotation operation amount is set to zero (0). Further, when driving only in rotation, the linear operation amount may be set to zero (0).

FIG. 8 is a block diagram showing a modification of the drive control method shown in FIG. In such a drive control method, the control signal f of the electromagnetic actuator 200A is fed forward with respect to the control signal of the electromagnetic actuator 200B, and the movable actuator 100 is linearly controlled by driving the electromagnetic actuators 200A and 200B in the same direction. Further, by rotating the compensation to the electromagnetic actuator 200B subtracts the difference _y b -y _a moving amount of each point from the rotation operation amount _{y d,} controls the rotation of the movable section 100.

  In such a control system, the amount of rotational operation is zero, and even when moving the movable part 100 in a straight line, the amount of movement may not be equal depending on the individual characteristics of each electromagnetic actuator. Therefore, in the control system of FIG. 8, the difference between the sensor 140B and the sensor 140A is fed back to compensate for the rotation, and the unnecessary rotation of the movable unit 100 is limited.

  With the algorithm described above, not only linear control of the movable part 100 but also rotation control is possible. The drive control method is not limited to the algorithm described above, and an equivalently converted algorithm such as shifting the position of the control input before and after the gain is also included in the technical scope of the present embodiment.

(Second embodiment: XY movable table)
In the first embodiment, the magnet 150 and the movable yoke 162 constitute the attraction unit. In the present embodiment, an attraction unit having another configuration using an attraction plate will be described.

  FIG. 9 is an assembly diagram showing a detailed portion of the XY movable stage in the second embodiment. Here, the fixed portion 110 is provided with a sensor 140, a magnet 150, a yoke 300, and a ball bearing 154, and the movable portion 100 is provided with a coil 160 and an adsorption plate 310. Yes.

  Since the sensor 140, the magnet 150, the ball bearing 154, and the coil 160, which have already been described as the constituent elements in the first embodiment, have substantially the same functions, redundant description is omitted, and the configurations are different here. The yoke 300 and the suction plate 310 will be mainly described.

  The yoke 300 is formed in a U shape and can be used as a part of a magnetic circuit by being used together with the magnet 150 provided therein. In this way, a magnetic force in the Z direction is generated in the space between the magnet 150 and the movable part side of the yoke 300, and the coil 160 of the movable part 100 moves between them. By passing a current through the coil 160, an electromagnetic force in the X or Y direction is generated, and a linear driving force corresponding to the amount of current can be obtained.

  The suction plate 310 is made of a material that generates an attractive force to the magnet, such as iron, and receives the leakage magnetic flux of the electromagnetic actuator to cause the movable portion 100 to be attracted to the fixed portion 110. Therefore, the suction part in the present embodiment includes the suction plate 310 and the electromagnetic actuator. Here, the suction of the movable part 100 can be performed with a non-mechanical and very simple configuration.

  FIG. 10 is an explanatory diagram for explaining the external appearance of the electromagnetic actuator 400 according to the second embodiment. Here, (a) is a front view, (b) is a plan view, and (c) is a side view. In the case of the electromagnetic actuator 400 as well, the length of the linear portion in the longitudinal direction of the coil 160 is formed to be larger than the width of the magnet 150 and the yoke 300 by the movable range in the X direction, similarly to the electromagnetic actuator 200 of FIG. The width in the short direction is formed to be smaller than the width of the magnet 150 by the movable range in the Y direction. This is because, as described above, within the movable range, the relationship between the magnetic flux by the magnet 150 and the current flowing through the coil 160 are made as equal as possible to obtain a uniform electromagnetic force.

  Further, the suction plate 310 is formed smaller than the width of the magnet 150 and the yoke 300 by the movable range in both the XY directions. This is because if the suction plate 310 deviates from the movable range, a suction force component in the X direction or the Y direction, not the Z direction, is generated, which hinders the driving force. When the suction plate 310 is within the movable range, the suction force in the X direction or the Y direction of the suction plate 310 can be ignored.

  FIG. 11 is an explanatory diagram showing changes in magnetic force when the movable unit 100 of the XY movable stage as described above is shifted in the Y direction. Here, the movable portion 100 is moved in the Y direction from −1.0 mm to +1.0 mm, and the magnetic force in each direction of the suction plate 310 at that time is shown. As understood from the figure, a magnetic force Fz of about −6.00 gf downward in the Z direction acts on the adsorption plate 310 to adsorb the movable part 100 and the fixed part 110.

  Further, although the magnetic force Fy in the Y direction also acts on the suction plate 310, the value can be ignored by the configuration in which the size of the suction plate 310 is made smaller than the width of the yoke 300.

  According to such a configuration, the weight of the movable unit 100 including the image sensor can be increased to 24.00 gf (6.00 × 4 locations). In this embodiment, the repulsive force of about 1.00 gf (Fy) does not significantly affect the driving of the electromagnetic actuator 400. Such a suction plate 310 can be formed in an appropriate size based on the weight of the movable part 100 and the electromagnetic force of the electromagnetic actuator 400.

  Further, when the size of the suction plate 310 is limited, the magnetic force can be adjusted by changing the distance between the movable unit 100 and the fixed unit 110.

  Due to the suction part by the suction plate 310 and the electromagnetic actuator, the movable part 100 and the fixed part 110 are sucked, and the movable part 100 can be prevented from being detached from the fixed part 110.

(Third embodiment: camera shake correction apparatus)
Next, a description will be given of a camera shake correction apparatus that uses the XY movable stage as a target for camera shake correction.

  FIG. 12 is a block diagram illustrating a schematic function of the camera shake correction apparatus 500 according to the third embodiment. The camera shake correction apparatus 500 includes a camera shake detection unit 510, an XY movable stage 520, and a control signal generation unit 530. Here, in order to facilitate understanding, a system in only one direction of XY has been described, but naturally control in other directions is also possible.

  The camera shake detection unit 510 detects a linear movement amount or angle that the camera shake correction apparatus 500 has shaken due to a user's camera shake or the like. The camera shake detection unit 510 can be formed of a position sensor, a speed sensor, an acceleration sensor, an angle sensor, an angular velocity sensor, an angular acceleration sensor, or the like.

  The XY movable stage 520 includes a movable part 100 provided with an image sensor 120, a fixed part 110 that supports the movable part 100, an adsorption part that attracts the movable part 100 to the fixed part 110 by magnetic force, and XY. A plurality of sensors 140 for detecting movement amounts of two different points on the movable part in the same direction that are not on a straight line extending in the one direction from the center of gravity of the movable part 100 in at least one direction of A plurality of electromagnetic actuators 200 for linearly controlling two different points on the movable part that are not on a straight line extending in one direction from the center of gravity of the movable part in one direction, and the movement detected by the sensor 140 The amount is transmitted to the control signal generation unit 530, and the control input from the control signal generation unit 530 is received to drive the movable unit 100.

  The control signal generation unit 530 is composed of a semiconductor integrated circuit such as a microcomputer (CPU, DSP) or FPGA (Field Programmable Gate Array), and the amount of rotation operation and the amount of rotation operation are determined from the amount of camera shake (linear movement amount or angle) of the camera shake detection unit 510. A linear operation amount is obtained, and based on the rotation operation amount and the rotation amount calculated from the difference between the movement amounts detected by the plurality of sensors 140, the movable unit 100 is moved to the XY plane using the plurality of electromagnetic actuators 200. Rotation control is performed, and the movable part is linearly controlled in the one direction using at least one of the plurality of electromagnetic actuators based on the linear operation amount and the movement amount detected by at least one of the plurality of sensors. .

  A more detailed operation of the control signal generation unit 530 in this embodiment will be described with reference to FIG. 12. The camera shake angular velocity θ ′ detected by the angular velocity sensor of the camera shake detection unit 510 is received, and the angular velocity θ ′ is integrated. Thus, the inclination angle θ due to camera shake is obtained. Further, the image plane movement amount y is calculated by d × tan (θ) (d is the focal length of the imaging device). The value of the sensor 140 is subtracted from the y calculated in this way and output to the electromagnetic actuator 200. Panning processing can also be performed when the angle θ is calculated.

  Here, position control using feedback is performed. However, the present invention is not limited to this, and any of position control, speed control, acceleration control, angular velocity control, and angular acceleration control can be applied.

  In the above configuration, like the above-described XY movable stage, the suction portion generates a suction force between the movable portion 100 and the fixed portion 110, thereby preventing the movable portion 100 from being detached from the fixed portion 110. In addition, the configuration of only two sensors and two electromagnetic actuators enables simultaneous control of the linear drive and the rotational drive of the movable part 100. Such a camera shake correction apparatus 500 does not have a mechanical structure for preventing rotation and attracting to a fixed portion, and therefore can be formed with an easy structure, and wasteful power consumption is not consumed.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the above embodiment, a photo interrupt is cited as the sensor 140. However, the present invention is not limited to this, and a displacement sensor that can be easily considered by those skilled in the art, such as an eddy current method or an ultrasonic method, is used in this embodiment. Can be applied.

  Moreover, although the ball bearing 154 is mentioned as a support mechanism of the movable part 100, other various support mechanisms which can disregard friction are applicable.

  Further, although the microcomputer and FPGA are cited as the control signal generation unit, the control signal generation unit can be formed by an analog circuit as long as the non-linear correction or the like is small or negligible.

  Note that each block in the drive control method of the present specification does not necessarily have to be processed in time series in the order described as a block diagram, and may include processing executed in parallel or individually.

It is the perspective view which showed the external appearance of the XY movable stage in 1st Embodiment. It is an assembly figure showing the detailed portion of the above-mentioned XY movable stage. It is the top view which represented XY movable stage which showed the position of a sensor abstractly. It is sectional drawing explaining the support mechanism of the movable part by a ball bearing. It is explanatory drawing for demonstrating the external appearance of an electromagnetic actuator. It is a block diagram explaining the schematic algorithm of the drive control method in 1st Embodiment. It is a block diagram explaining the schematic algorithm of the other drive control method in 1st Embodiment. FIG. 8 is a block diagram showing a modified example of the drive control method shown in FIG. 7. It is an assembly figure showing the detailed portion of the XY movable stage in a 2nd embodiment. It is explanatory drawing for demonstrating the external appearance of the electromagnetic actuator in 2nd Embodiment. It is explanatory drawing which showed the change of the magnetic force at the time of shifting the movable part of the above XY movable stages to a Y direction. It is the block diagram which showed the schematic function of the camera-shake correction apparatus in 3rd Embodiment. It is explanatory drawing which showed the movable direction of the movable part at the time of providing a shaft in a movable stage. It is explanatory drawing which showed the movable direction at the time of providing a tension spring in a movable stage.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Movable part 110 Fixed part 120 Image sensor 140 Sensor 150 Magnet 152 Fixed side yoke 160 Coil 162 Movable side yoke 200,400 Electromagnetic actuator 300 yoke 310 Adsorption plate

Claims (5)

A camera shake detection unit that detects the amount of camera shake ,
A movable portion imaging element is provided, and a fixing portion supporting the movable portion, and a suction unit for sucking the movable portion to the fixed portion by a magnetic force, the X direction in the XY plane perpendicular to the optical axis in at least one direction and the Y direction, and a plurality of sensors for detecting not a straight line extending in the one direction from the center of gravity of the movable portion, the movement amount in the same direction of the two points of difference on the movable portion, respectively, the not on a straight line extending in the one direction from the center of gravity of the movable portion in one direction, XY movable stage and a plurality of electromagnetic actuators for linear control respective different two points a on the movable part and,
In order to compensate for the amount of rotation operation and the amount of camera shake, which is a value obtained by converting the angle at which the movable unit should rotate in order to compensate for the amount of camera shake from the amount of camera shake of the camera shake detection unit. It obtains a linear operation amount the movable portion is a value to be linearly moved, based on the rotation amount calculated from the difference between the rotational operation amount and the movement amount detected by the plurality of sensors, the plurality of electromagnetic actuators and rotation control said movable portion on the XY plane with, on the basis of said linear operation amount and the movement amount detected at least one of said plurality of sensors, the using at least one of the plurality of electromagnetic actuators control signal generating unit for linearly controlling the movable portion in the one direction, Bei give a,
The fixed portion includes the sensor, a yoke having a cross-section of a “U” shape, and a magnet provided with a gap in the yoke, and the movable portion includes an adsorption plate and the yoke. A coil inserted movably in a gap between the iron and the magnet, the yoke, the magnet, and the coil constitute the electromagnetic actuator, and the electromagnetic actuator and the suction plate constitute the suction portion ,
The image stabilization apparatus according to claim 1, wherein a width of the suction plate is smaller than a width of the yoke in both the X and Y directions .   The camera shake correction apparatus according to claim 1, wherein the plurality of electromagnetic actuators of the XY movable stage are arranged to face each other with the center of gravity of the movable part interposed therebetween.   The camera shake correction device according to claim 2, wherein the plurality of electromagnetic actuators of the XY movable stage are arranged diagonally with respect to the movable portion.   4. The camera shake correction apparatus according to claim 1, wherein the plurality of sensors of the XY movable stage are arranged to face each other with the center of gravity of the movable part interposed therebetween. 5. The camera shake correction apparatus according to claim 4, wherein the plurality of sensors of the XY movable stage are arranged diagonally to the movable part.

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