JP4758211B2 - Camera shake correction unit and photographing apparatus - Google Patents

Description

  The present invention relates to a camera shake correction unit having a mechanism for correcting camera shake, and an imaging apparatus that performs shooting by capturing subject light incident via an imaging optical system.

  In recent years, it has been widely practiced to incorporate a photographing device for photographing a subject in a small device such as a mobile phone. By providing a photographing device in a small device that is always carried around, it is possible to easily shoot anytime without having to carry a digital camera or a video camera. In addition, these small devices are generally equipped with a data communication function using wireless or infrared rays in advance, and the captured images are immediately taken on the spot to other mobile phones, personal computers, etc. There is also an advantage that can be sent to.

  Here, when taking a picture using a small digital camera, a mobile phone, or the like, the digital camera or the like is moved when the release switch is pressed, and a problem of camera shake that causes an image shift in the taken image is likely to occur. In recent years, holding a digital camera or the like with only one hand, and taking a picture of himself / herself by extending his / her hand has been widely performed, and camera shake is likely to occur.

With regard to such a problem, Patent Document 1 and Patent Document 2 describe a camera shake correction device that corrects a shift in an imaging position due to movement of an imaging device by moving a camera shake correction lens with a motor or the like. ing. According to the techniques described in Patent Document 1 and Patent Document 2, for example, a camera shake sensor that detects movement of the photographing apparatus is mounted, and the camera shake correction lens is moved according to the detection result of the camera shake sensor. As a result, it is possible to obtain a beautifully captured image that does not cause camera shake.
Japanese Patent Laid-Open No. 3-186823 JP 2005-114811 A

  However, the techniques described in Patent Document 1 and Patent Document 2 require a large lens motor composed of a coil, a yoke, a magnet, and the like in order to move the camera shake correction lens. The size and weight will increase significantly. Furthermore, since it is necessary to secure sufficient power for driving the lens motor in addition to the power for executing the normal photographing function, the mobile phone is required to be reduced in size, weight and power saving. Has a problem that it is difficult to install.

  In view of the circumstances described above, an object of the present invention is to provide a small camera shake correction unit and an imaging apparatus that can correct camera shake power saving.

The image stabilization unit of the present invention that achieves the above object includes a correction optical system that corrects image blur formed by the imaging optical system, and
A camera shake detection unit for detecting camera shake;
A frame,
A guide portion extending in a predetermined guide direction in a plane intersecting the optical axis of the imaging optical system;
A moving unit that supports the correction optical system, receives a force in the guiding direction, is guided by the guiding unit, and moves in the guiding direction with respect to the frame;
Extending along the guide direction, one end is fixed to the frame, and the other end relative to the one end is fixed to the moving part. A drive unit comprising a member and an electrode for applying a voltage to the elastic member;
Camera shake correction that corrects the deviation of subject light caused by camera shake by moving the correction optical system in the guide direction by applying a voltage according to the detection result of the camera shake detection unit to the electrode and moving the moving unit to the telescopic member And a control unit.

  According to the camera shake correction unit of the present invention, the elastic member is expanded and contracted according to the camera shake detection result detected by the camera shake detection unit, so that the moving unit is moved in the guide direction and the correction supported by the moving unit. The optical system is also moved in the guide direction. At this time, the expansion / contraction degree of the expansion / contraction member is adjusted according to the applied voltage, and the position of the correction optical system is adjusted according to the expansion / contraction degree, so that the correction optical system is driven with high power saving and high accuracy. Further, since a large drive mechanism such as a coil or a magnet is not required, the whole camera shake correction unit can be miniaturized and can be mounted on a small device such as a mobile phone.

In the camera shake correction unit of the present invention, the correction optical system is supported by the moving unit so as to be movable in both the first direction and the second direction different from each other in the plane.
The guide section includes a first guide section and a second guide section extending in a first direction and a second direction, respectively.
The moving unit supports the correction optical system so as to be movable in the second direction, and receives a force in the first direction and is guided by the first guide unit to move in the first direction. And a second moving unit that supports the correction optical system movably in the first direction and that is guided by the second guide unit and moves in the second direction upon application of force in the second direction. And with
The drive unit extends along the first direction, is fixed to the frame body and the first moving unit, and moves the first moving unit in the first direction. A first electrode for applying a voltage to the expandable member, and extending along the second direction, fixed to the frame and the second moving part, and moving the second moving part in the second direction A second elastic member to be applied, and a second electrode for applying a voltage to the second elastic member,
The camera shake correction control unit preferably applies a voltage to both the first electrode and the second electrode.

  By moving the correction optical system in both the first direction and the second direction which are different from each other, it is possible to accurately correct the blurring of the image formed by the imaging optical system.

  In the camera shake correction unit of the present invention, it is preferable that the elastic member is a polymer actuator.

  The polymer actuator has a property of expanding and contracting according to an applied voltage, and further has a large expansion and contraction amount, and therefore can be preferably applied as the expansion and contraction member according to the present invention.

  In the camera shake correction unit of the present invention, it is preferable that in the drive unit, the expansion / contraction member has a tube shape, and the electrode applies a voltage between the outer surface and the inner surface of the expansion / contraction member. .

  According to the camera shake correction unit of the preferred embodiment of the present invention, the moving part can be reliably moved by the stretching force of the telescopic member, and the camera shake can be corrected with high accuracy.

  In the camera shake correction unit of the present invention, it is preferable that the drive unit is provided with a spring for preventing buckling of the elastic member on at least the inner surface side of the tube shape of the elastic member.

  By attaching a spring to the expansion / contraction member and preventing the buckling of the expansion / contraction member, the correction optical system can be accurately moved in the guide direction over a long period of time, and camera shake can be reliably corrected.

  Moreover, in the camera shake correction unit of the present invention, it is preferable that the drive unit has a spring serving as an electrode.

  By using a spring for preventing the elastic member from buckling as an electrode, the entire apparatus can be further downsized.

Further, in the camera shake correction unit of the present invention, a focus adjustment optical system that adjusts the focus of an image formed by the imaging optical system by moving in the optical axis direction;
One end is fixed to the frame that extends in the optical axis direction of the focus adjustment optical system, and the other end relative to the one end is fixed to the focus adjustment optical system. A third drive unit comprising a third elastic member for moving the system in the optical axis direction, and a third electrode for applying a voltage to the third elastic member;
A focus adjustment control unit configured to adjust the focus by moving the focus adjustment optical system in the optical axis direction by applying a voltage to the third electrode to expand and contract the third expansion member. To do.

  In addition to the correction optical system, the focus adjustment optical system can also be moved along the optical axis using the third telescopic member, so that camera shake correction and focus adjustment can be realized for power saving. Further, since the capacitance of the third elastic member changes according to the expansion and contraction, the position of the focus adjustment optical system can be detected by measuring the capacitance of the third elastic member, and the high-precision focus adjustment is performed. Can be realized.

  In the camera shake correction unit of the present invention, it is preferable that the third elastic member is configured by laminating a plurality of elastic members.

By applying the third elastic member in which a plurality of elastic members are stacked, the amount of expansion and contraction of the entire third elastic member can be increased, and focus adjustment can be performed reliably. The image stabilization unit of the present invention includes a focus adjustment optical system that adjusts the focus of an image formed by the imaging optical system by moving in the optical axis direction.
The frame body restricts movement in the direction intersecting the optical axis of the focus adjustment optical system, and guides movement of the focus adjustment optical system in the optical axis direction.
Extends in a direction intersecting the optical axis of the focus adjustment optical system, one end is fixed to the frame, and the other end relative to the one end is fixed to the focus adjustment optical system. A fourth drive unit comprising: a deflection member that moves the focus adjustment optical system in the optical axis direction by bending between the second electrode and the fourth electrode for applying a voltage to the deflection member;
It is also preferable to include a focus adjustment control unit that adjusts the focus by moving the focus adjustment optical system in the optical axis direction by applying a voltage to the fourth electrode to expand and contract the bending member.

  By fixing the deflecting member to the frame and the focus adjustment optical system, and deflecting the deflecting member and moving the focus adjustment optical system in the optical axis direction, it is possible to reduce camera shake and adjust the focus to save power. can do. Furthermore, by measuring the capacitance of the fourth elastic member and detecting the position of the focus adjustment optical system based on the measured capacitance, the subject can be focused with high accuracy.

In addition, the imaging apparatus of the present invention that achieves the above object is an imaging apparatus that performs imaging by capturing subject light that has entered via an imaging optical system.
A correction optical system for correcting blurring of an image formed by the imaging optical system;
A camera shake detection unit for detecting camera shake;
A frame,
A guide portion extending in a predetermined guide direction in a plane intersecting the optical axis of the imaging optical system;
A moving unit that supports the correction optical system, receives a force in the guiding direction, is guided by the guiding unit, and moves in the guiding direction with respect to the frame;
Extending along the guide direction, one end is fixed to the frame body, and the other end with respect to the one end is fixed to the moving part. When the voltage application is released, the moving part is moved in the guiding direction. A drive unit comprising an elastic member and an electrode for applying a voltage to the elastic member;
By applying a voltage according to the detection result by the camera shake detection unit to the electrode and moving the moving unit to the telescopic member, the correction optical system is moved in the guide direction to correct the deviation of the subject light caused by the camera shake An imaging apparatus comprising: a camera shake correction control unit.

  According to the photographing apparatus of the present invention, camera shake is reliably corrected, and a high-quality photographed image can be acquired.

  Note that only the basic form of the photographing apparatus according to the present invention is shown here, but the photographing apparatus according to the present invention includes not only the above basic form but also each form of the above-described camera shake correction unit. Various corresponding forms are included.

  ADVANTAGE OF THE INVENTION According to this invention, the small camera-shake correction unit and imaging device which can correct camera shake to power saving can be provided.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an external perspective view of a mobile phone to which an embodiment of the present invention is applied. The mobile phone 100 is equipped with a photographing function for photographing a subject, and a camera shake unit for correcting camera shake is detachably mounted on a photographing lens 110 provided on the back surface.

  A front view of the mobile phone 100 is shown in FIG. A liquid crystal panel 101 on which a menu screen or a photographed image is displayed is provided on the front surface of the mobile phone 100, a speaker (see FIG. 2) is provided inside, a mouthpiece 102 for emitting sound emitted from the speaker, a telephone A first antenna 103a for transmitting and receiving data such as voice and mail via a station, a selection button 104 used as a shutter button when selecting various functions and shooting, a push button for inputting a telephone number 105, a microphone (see FIG. 2) is provided inside, the earpiece 106 for transmitting the voice to the microphone, the confirmation button 107 for confirming the telephone number entered by the user, the power button 108, and the central office The second antenna 109a for transmitting and receiving images and address information by wireless communication for short distance is provided. .

  FIG. 1B shows a rear view of the mobile phone 100. A photographing lens 110 is provided on the back surface of the mobile phone 100, and a recess 110 b is provided in the housing 100 a of the mobile phone 100. The mobile phone 100 is provided with a camera shake unit 200 that corrects camera shake by moving the camera shake correction lens 201, and a convex portion (not shown in FIG. 1; see FIG. 7) provided on the camera shake unit 200 is provided. The camera shake unit 200 is detachably attached to the mobile phone 100 by being inserted into the recess 110b of the body 100a. The camera shake correction lens 201 corresponds to an example of a correction optical system according to the present invention.

  FIG. 2 is a block diagram of the mobile phone 100 to which the camera shake unit 200 is attached.

  In the mobile phone 100, a photographing lens 110, an iris 111, a CCD 112, an A / D (Analog / Digital) conversion unit 113, a microphone 106, a speaker 102, an interface unit 120, a first antenna 103a, a first transmission / reception unit 103, Input controller 130, image signal processing unit 140, video encoder 150, image display device 160, second antenna 109a, second transmission / reception unit 109, memory 170, CPU 180, camera shake sensor 182, voltage application unit 183, media controller 190, and diagram 1 is provided with various switches 181 such as a selection button 104 and a push button 105, and a recording medium 300 is connected thereto.

  The CPU 180 transmits processing instructions to the various elements of the mobile phone 100 shown in FIG. 2, and controls the various elements. For example, when the selection button 104 in FIG. 1 is pressed in a state where a shooting mode for shooting is set, the CPU 180 gives instructions to various elements shown in FIG. 2 and starts shooting.

  Here, originally, a plurality of lenses are provided in a photographing apparatus for photographing a subject. In FIG. 2, these lenses are schematically shown as photographing lenses 110. The photographing lens 110 corresponds to an example of an imaging optical system according to the present invention. The iris 111 is an aperture that adjusts the amount of subject light received by the CCD 112.

  The camera shake sensor 182 detects the movement of the mobile phone 100, and the camera shake unit 200 shown in FIG. 1 moves the camera shake correction lens 201 in response to the application of a voltage, thereby causing a result of the movement of the mobile phone 100. This is to correct image position deviation. The detection result of the camera shake sensor 182 is transmitted to the CPU 180, and the CPU 180 determines the applied voltage to the camera shake unit 200 based on the detection result, and the determined voltage is applied to the camera shake sensor 182 from the voltage application unit 183. The camera shake sensor 182 is an example of a camera shake detection unit according to the present invention, and the combination of the CPU 180 and the voltage application unit 183 corresponds to an example of a camera shake correction control unit according to the present invention. The configuration of the camera shake unit 200 and the camera shake correction process will be described in detail later.

  When the selection button 104 in FIG. 1 is pressed to start photographing, the CCD 112 receives subject light that has passed through the camera shake correction lens 201 and the photographing lens 110 in the camera shake unit 200, and subjects based on the subject light. The image is read as an object signal that is an analog signal. The subject signal generated by the CCD 112 is converted into digital photographed image data by the A / D converter 113. The converted captured image data is sent to the image signal processing unit 140 via the input controller 130.

  The image signal processing unit 140 performs image processing such as RGB level adjustment and gamma adjustment on the image data, and further performs compression processing on the image data after the image processing. The compressed image data is once sent to the memory 170.

  The memory 170 stores a program to be executed in the mobile phone 100, a high-speed SDRAM used as an intermediate buffer, data for various menu screens, data stored by a user, and the like. An SRAM that is a storage memory and a VRAM that stores compressed image data are included. The VRAM is divided into a plurality of areas, image data is stored in the plurality of areas in order, and the stored image data is sequentially read out to the video encoder 150 and the media controller 190.

  The video encoder 150 acquires compressed image data from the memory 170 in accordance with an instruction from the CPU 180, and converts the compressed image data into a data format that can be displayed on the liquid crystal panel 101. The converted image data is sent to the image display device 160, and the image display device 160 displays an image represented by the image data on the liquid crystal panel 101. The media controller 190 is for recording the compressed image data stored in the memory 170 on the recording medium 300 and for reading the image data recorded on the recording medium 300.

  When a telephone number is input using the push button 105 shown in FIG. 1 and the confirm button 107 is pressed, the telephone number is set and communication with the partner apparatus is started. At this time, communication information such as the telephone number of the mobile phone 100 and the input telephone number is transmitted from the CPU 180 to the first transmission / reception unit 103, the communication information is converted into radio waves and transmitted to the antenna 103a, and radio waves are transmitted from the antenna 103a. Be emitted. The radio wave emitted from the first antenna 103a is transmitted to a telephone station via a joint antenna (not shown) provided at various places such as a building and a power pole, and the other party to which a designated telephone number is assigned at the telephone station. A connection with the device is established.

  When the connection with the partner apparatus is established, the voice uttered by the user toward the mobile phone 100 is collected by the microphone 106 shown in FIG. 1 and the collected voice is converted into a radio wave representing voice data by the interface unit 120. It is converted and transmitted to the counterpart device by the first antenna 103a of the first transceiver 103. The radio wave received via the first antenna 103a is converted into audio data by the interface unit 120, and is emitted as sound from the speaker 102 also shown in FIG. The first transmission / reception unit 103 and the first antenna 103a transmit / receive not only voice data but also mail data representing mail using a mail address instead of a telephone number. The mail data received by the first antenna 103a and digitized by the first transmission / reception unit 103 is stored in the memory 170 by the input controller 130.

  In addition, the mobile phone 100 does not pass through the telephone station, apart from the communication interface (the first transmitting / receiving unit 103 and the first antenna 103a) for communicating with other devices such as other mobile phones through the telephone station. In addition, a wireless communication interface (second transmission / reception unit 109, second antenna 109a) for performing communication by short-range wireless communication is also provided. As a communication interface for near field communication, infrared communication, Bluetooth, or the like can be applied. In the present embodiment, infrared communication is applied as a communication interface. When infrared light directly transmitted from another mobile phone or the like is received by the second antenna 109a, an electrical signal based on the received infrared light is transmitted. 2 Picked up by the transmitting / receiving unit 109 and converted into digital data. Conversely, when data is transmitted to the external device, the data is transmitted to the second transmission / reception unit 109, and the data is converted into radio waves by the second transmission / reception unit 109 and emitted from the second antenna 109a.

  When infrared rays representing an image are received by the second antenna 109a, the second transmitting / receiving unit 109 converts an electrical signal based on the infrared rays into image data. The converted image data is sent to the image display device 160 and the image represented by the image data is displayed on the liquid crystal panel 101 or recorded on the recording medium 300 via the media controller 190 in the same manner as the captured image data. .

  The mobile phone 100 is basically configured as described above.

  Here, since the mobile phone 100 is small, the mobile phone 100 is likely to move when the selection button 104 in FIG. 1 is pressed. However, the camera shake can be reduced by attaching the camera shake unit 200 to the mobile phone 100. it can. Hereinafter, the camera shake unit 200 and the camera shake correction process will be described in detail.

  First, an example of a camera shake unit that has been conventionally used will be described.

  FIG. 3 is an exploded perspective view of a conventional camera shake unit.

  In the following description, the pitch direction (vertical direction) when the imaging device (in this embodiment, the mobile phone 100 to which the camera shake unit 200 is mounted) mounted with the camera shake unit is viewed from the front is expressed by the alphabet P. In the following description, the yaw direction (lateral direction) is represented by the letter Y.

  The camera shake unit 10 shown in FIG. 3 mainly includes a camera shake correction lens 11, a lens holding unit 12 that holds the camera shake correction lens 11, a pitch slider 20P that supports the lens holding unit 12, a yaw slider 20Y, and a pitch slider 20P in the pitch direction. A coil motor 30P to be moved, a coil motor 30Y to move the yaw slider 20Y in the yaw direction, and a housing cylinder 40 in which they are housed.

  The accommodating cylinder 40 includes a pitch guide bar 41P extending in the pitch direction, a yaw guide bar 41Y extending in the yaw direction, a pitch sensor 42P for detecting the position of the pitch slider 20P, and a yaw sensor 42Y for detecting the position of the yaw slider 20Y. Is provided.

  The coil motor 30P that moves the pitch slider 20P is constituted by a coil 31P, a U-shaped yoke 32P, and a disk-shaped yoke 50PY. The coil 31P is held by the pitch slider 20P, and the U-shaped yoke 32P is supported by the housing cylinder 40. Is done. Magnets 33P and 51P are attached to the U-shaped yoke 32P and the disk-shaped yoke 50PY at positions facing the coil 31P, respectively.

  The coil motor 30Y for moving the yaw slider 20Y includes a coil 31Y, a U-shaped yoke 32Y, and a disk-shaped yoke 50PY shared with the coil motor 30P. The coil 31Y is held by the yaw slider 20Y and is U-shaped. The yoke 32Y is supported by the housing cylinder 50PY. Magnets 32Y (not shown) and 51Y are attached to the U-shaped yoke 32Y and the disk-shaped yoke 50PY at positions facing the coil 31Y, respectively.

  The lens holding portion 12 has a substantially rectangular outer shape, and a through-hole 13P penetrating in the pitch direction and a through-hole 13Y penetrating in the yaw direction are formed in the substantially rectangular edge portion. ing.

  The pitch slider 20P is provided with a main guide portion 21P extending in the pitch direction and a sub guide portion 22P extending in the yaw direction. The main guide portion 21P has a through hole 23P penetrating in the pitch direction, and the guide rod 41P of the storage cylinder 40 is fitted into the through hole 23P, so that the pitch slider 20P is inserted into the storage cylinder 40 in the pitch direction. It is supported movably. Further, the sub guide portion 22P is provided with a coil holding portion 24P for holding the coil 31P of the coil motor 30P, and a guide rod 25P extending in the yaw direction. The guide rod 25P is a through hole of the lens holding portion 12. The pitch slider 20P supports the lens holding part 12 so as to be movable in the yaw direction by being fitted into 13Y.

  The yaw slider 20Y has a through hole 23Y penetrating in the yaw direction in the main guide portion 21Y extending in the yaw direction, and the coil 31Y of the coil motor 30Y is provided in the sub guide portion 22Y extending in the pitch direction. A coil holding portion 24Y for holding and a guide bar 25Y extending in the pitch direction are provided. The yaw slider 20Y is supported by the housing cylinder 40 so as to be movable in the yaw direction by inserting the guide bar 41Y of the housing cylinder 40 into the through hole 23Y, and the guide bar 25Y is inserted into the through hole 13P of the lens holding portion 12. By inserting, the lens holding part 12 is supported movably in the pitch direction.

  When the coil motor 30P drives the pitch slider 20P, the pitch slider 20P is guided by the guide rod 41P of the housing cylinder 40 and moved in the pitch direction. At this time, the lens holding portion 12 is pulled by the pitch slider 20P and moved in the pitch direction along the guide rod 22Y of the yaw slider 20Y. Conversely, when the coil motor 30Y drives the yaw slider 20P, the yaw slider 20Y is guided by the guide rod 41Y of the housing cylinder 40 and moved in the yaw direction, and the lens holding portion 12 is also guided by the guide rod 22P of the pitch slider 20P. Along the yaw direction. Thus, according to the camera shake unit 10 shown in FIG. 3, by driving one slider, the camera shake correction lens 11 can be moved without moving the other slider, and wasteful power consumption can be suppressed. . However, in the camera shake unit 10 shown in FIG. 3, in order to move the camera shake correction lens 11, a coil motor composed of a coil, a U-shaped yoke, and a disk-shaped yoke is required. Therefore, it is difficult to mount on the mobile phone 100.

  The camera shake unit 200 of the present embodiment is intended to reduce the size and power consumption of the camera shake unit 10 shown in FIG.

  FIG. 4 is a cross-sectional view of the camera shake unit 200 of this embodiment when viewed from the front.

  As shown in FIG. 4, the camera shake unit 200 also has a camera shake correction lens 201, a lens holding unit 210 that holds the camera shake correction lens 201, and a pitch that supports the lens holding unit 210, as in the camera shake unit 10 shown in FIG. Although the slider 220P and the yaw slider 220Y are provided, the camera shake unit 200 of this embodiment is provided with a pitch slider 220P in response to application of electric power instead of the coil motors 30P and 30Y of the camera shake unit 10 shown in FIG. A camera shake actuator 230P that moves in the pitch direction (vertical direction) and a camera shake actuator 230Y that moves the yaw slider 220Y in the yaw direction (horizontal direction) are provided, and are housed in the housing 200a.

  A pitch guide bar 202P extending in the pitch direction and a yaw guide bar 202Y extending in the yaw direction are fixed to the housing 200a, similarly to the camera shake correction unit 10 shown in FIG. The pitch guide bar 202P and the yaw guide bar 202Y correspond to an example of a guide unit according to the present invention.

  The lens holding part 210 is provided with legs 211 extending in the pitch direction and the yaw direction, respectively, and these legs 211 serve as the through holes 13P and 13Y of the camera shake correction unit 10 shown in FIG. A through hole (not shown) penetrating in the pitch direction and a through hole (not shown) penetrating in the yaw direction are formed.

  Similarly to the camera shake correction unit 10 shown in FIG. 3, a main guide portion 221P having a through hole (not shown) penetrating in the pitch direction and a guide rod 223P extending in the yaw direction are fixed to the pitch slider 220P. The sub-guide portion 222P is provided. When the pitch guide rod 202P of the housing 200a is fitted into the through hole of the main guide portion 221P, the pitch slider 220P is supported by the housing cylinder 40 so as to be movable in the pitch direction, and the guide rod 223P is supported by the legs 211 of the lens holding portion 210. The lens holding portion 210 is supported so as to be movable in the yaw direction by being fitted into a through-hole penetrating in the yaw direction.

  Similarly to the pitch slider 220P, the yaw slider 220Y includes a main guide portion 221Y having a through hole (not shown) penetrating in the yaw direction, and a sub guide portion 222Y to which a guide rod 223Y extending in the pitch direction is fixed. Is provided. When the yaw guide rod 202Y of the housing 200a is fitted into the through hole of the main guide portion 221Y, the yaw slider 220P is supported by the housing tube 40 so as to be movable in the yaw direction, and the guide rod 223Y is attached to the foot 211 of the lens holding portion 210. The lens holding part 210 is supported so as to be movable in the pitch direction by being fitted into a through-hole penetrating in the pitch direction. The pitch slider 220P and the yaw slider 220Y correspond to an example of a moving unit according to the present invention.

  The camera shake actuators 230P and 230Y are polymer actuators that expand and contract in response to voltage application release. The camera shake actuators 230P and 230Y correspond to an example of a drive unit according to the present invention.

  Here, the description of FIG. 4 is temporarily interrupted, and the operation principle and configuration of the camera shake actuators 230P and 230Y will be described. The polymer actuator is described in detail in US Pat. No. 6,891,317, and this polymer actuator can be suitably applied as the camera shake actuators 230P and 230Y of this embodiment. First, the operation principle of the polymer actuator will be briefly described.

  FIG. 5 is a diagram for explaining the operation principle of the polymer actuator.

  As shown in FIG. 5, the polymer actuator 60 is configured by sandwiching a polymer material 63 (for example, an acrylic elastomer) between two electrodes 62 and 64.

  When no voltage is applied from the voltage application unit 61 to the polymer actuator 60, as shown in FIG. 5A, the two electrodes 62 and 64 are not attracted and the polymer actuator 60 is not expanded or contracted ( Length L1).

  For example, when a voltage having a polarity in which the upper electrode 62 is an anode and the lower electrode 64 is a cathode is applied to the polymer actuator 60 from the voltage application unit 61, as shown in FIG. A positive charge 71 is released, and a negative charge 72 is released to the lower electrode 64. As a result, the positive charge 71 and the negative charge 72 released to the two electrodes 62 and 64 are attracted to each other by the electrostatic force, and the polymer material 63 is pressed between the two electrodes 62 and 64. As a result, the polymer actuator 60 is thinly stretched, and the polymer actuator 60 extends to the length L2. Here, since the magnitude of the electrostatic force formed by the two electrodes 62 and 64 changes depending on the magnitude of the voltage applied from the voltage application unit 61, the applied voltage is adjusted to adjust the applied voltage of the polymer actuator 60. The degree of expansion / contraction can be controlled.

  When the voltage application from the voltage application unit 61 is stopped, the electrostatic force between the two electrodes 62 and 64 disappears, and the polymer actuator 60 contracts to the length L1 as shown in FIG. To do.

  In the camera shake actuators 230P and 230Y applied to the camera shake unit 200 of this embodiment, the amount of expansion and contraction is increased by forming the polymer actuator 60 shown in FIG. 5 into a tube shape.

  FIG. 6 is a cross-sectional view when the camera shake actuator applied to the camera shake unit 200 of the present embodiment is cut along the expansion / contraction direction. Here, the camera shake actuator 230Y will be described as a representative of the camera shake actuators 230P and 230Y.

  The camera shake actuator 230 </ b> Y includes a tube 231 made of a polymer material, an outer spring 232 that surrounds the outside of the tube 231, and an inner spring 233 that is fitted inside the tube 231. Further, a metal screw 235 fixed to the housing 200a is fitted to one end of the tube 231, and a cap 234 fixed to the main guide portion 221Y of the yaw slider 220Y is fitted to the other end. It is mated. The metal screw 235 and the cap 234 have thick tip portions, and the problem that the metal screw 235 and the cap 234 come out of the tube 231 due to expansion and contraction of the camera shake actuator 230Y is avoided. The tube 231 corresponds to an example of the elastic member referred to in the present invention.

  The outer spring 232 and the inner spring 233 are in close contact with the tube 231 and serve as an electrode for suppressing the buckling of the tube 231 and expanding and contracting the tube 231. The outer spring 232 and the inner spring 233 correspond to an example of the electrode according to the present invention. For example, when a voltage having a polarity in which the outer spring 232 serves as an anode and the inner spring 233 serves as a cathode is applied from the voltage application unit 183 illustrated in FIG. 2, positive charges are released to the outer spring 232 via the lead wire 236. At the same time, negative charges are released to the inner spring 233 through the lead wire 236 and the metal screw 235, and these charges are attracted by electrostatic force. As a result, as shown in FIG. 6B, the tube 231 is thinly stretched and the camera shake actuator 230Y is stretched.

  Here, the camera shake actuator 230Y has been described, but the camera shake actuator 230P has the same configuration as the camera shake actuator 230Y.

  Returning to FIG.

  When a voltage is applied to the camera shake actuator 230P fixed to the pitch slider 220P, the camera shake actuator 230P extends to a length corresponding to the applied voltage, and the pitch slider 220P is driven in the pitch direction by the camera shake actuator 230P. . As a result, the lens holding portion 211 pulled by the pitch slider 220P is guided by the guide bar 223Y of the yaw slider 220Y and moved in the pitch direction. In addition, when a voltage is applied to the camera shake actuator 230Y fixed to the yaw slider 220Y, the camera shake actuator 230Y is expanded to drive the yaw slider 220Y in the pitch direction, and the lens holding unit 211 is a guide rod of the pitch slider 220P. It is guided by 223P and moved in the yaw direction. The camera shake actuators 230P and 230Y can be driven with less power than conventional coil motors and the like, and can be reduced in size because they do not require coils or magnets.

  FIG. 7 is a cross-sectional view of the vicinity of the lens when the mobile phone 100 to which the camera shake unit 200 is attached is viewed from above.

  As shown in FIG. 7, the camera shake correction lens 201 includes a front lens 2011 supported by a housing 220 a and a rear lens 2012 held by a lens holding frame 210. Further, the housing 200a of the camera shake unit 200 is provided with a convex portion 2001. The convex portion 2001 is inserted into the concave portion 100b of the digital camera 100 shown in FIG. The camera shake unit 200 is attached to the digital camera 100 so that the optical axis O of the photographing lens 110 and the optical axis of the camera shake correction lens 201 built in the camera shake unit 200 are aligned.

  When the selection button 104 in FIG. 1 is pressed and shooting is started, the movement sensor 182 shown in FIG. 2 detects the movement of the mobile phone 100 and transmits the detection result to the CPU 180. In the memory 170, the position of the camera shake correction lens 201 and the voltage value applied to the camera shake actuators 230P and 230Y necessary to move the camera shake correction lens 201 to the position are stored in advance in association with each other. When the CPU 180 acquires the detection result from the camera shake sensor 182, the CPU 180 calculates the position of the camera shake correction lens 201 for correcting the shift of the imaging position due to the movement of the mobile phone 100, and corresponds to the calculated lens position from the memory 170. The applied voltage value is acquired, and the acquired applied voltage value is transmitted to the voltage applying unit 183. The voltage application unit 183 applies the voltage value transmitted from the CPU 180 to each of the camera shake actuators 230P and 230Y.

  The camera shake actuators 230P and 230Y extend to a length corresponding to the applied voltage, and move the lens holding frame 210, thereby moving the camera shake correction lens 201 to a position calculated by the CPU 180. As a result, the object light is imaged at a correct position on the CCD 112 by the camera shake correction lens 201, and the camera shake is corrected.

  As described above, the camera shake unit 200 according to the present embodiment is power-saving and small in size, and thus can be mounted on the mobile phone 100, and camera shake can be corrected with high accuracy.

  Above, description of 1st Embodiment of this invention is complete | finished and 2nd Embodiment of this invention is described. Since the mobile phone according to the second embodiment of the present invention has substantially the same configuration as the mobile phone according to the first embodiment of the present invention, the same components are denoted by the same reference numerals and description thereof is omitted. Only differences between the first embodiment and the second embodiment will be described.

  The mobile phone according to the present embodiment has substantially the same configuration as the mobile phone 100 according to the first embodiment shown in FIGS. 1 to 7, but the configuration of the camera shake actuator that drives the camera shake correction lens 201 and the camera shake are the same. It differs from the first embodiment in that a mechanism for moving the correction lens 201 in the optical axis direction is provided.

  FIG. 8 is a cross-sectional view of the camera shake actuator according to this embodiment when cut along the direction of expansion and contraction. Here, only the camera shake actuator 230Y ′ that moves the camera shake correction lens 201 in the yaw direction will be described, and description of the camera shake actuator 230P ′ that moves the camera shake correction lens 201 in the pitch direction will be omitted.

  The camera shake actuator 230Y ′ is different from the camera shake actuator 230Y of the first embodiment shown in FIG. 6 in that the outer spring 232 is provided only on the side in contact with the lead wire 236. Thus, by providing the outer spring 232 not only on the entire outer surface of the tube 231 but only on the side in contact with the lead wire 236, the camera shake actuator 230Y ′ can be further reduced in size.

  FIG. 9 is a cross-sectional view of the camera shake unit 400 of the present embodiment when viewed from above.

  As shown in FIG. 9, the camera shake unit 400 of the present embodiment includes, in addition to various elements constituting the camera shake unit 200 of the first embodiment shown in FIG. 7, between the rear lens 2012 and the lens holding frame 210. A focus actuator 410 that expands and contracts in the optical axis direction is provided. The focus actuator 410 is formed by stacking a plurality of polymer actuators 60 shown in FIG. 5 in the thickness direction. When a voltage is applied from the voltage application unit 183 in accordance with an instruction from the CPU 180 shown in FIG. The thickness of the focus actuator 410 changes according to the applied voltage. The camera shake correction lens 201 corresponds to an example of a correction optical system according to the present invention and corresponds to an example of a focus adjustment optical system according to the present invention. The focus actuator 410 is an example of a third drive unit according to the present invention, and the combination of the CPU 180 and the voltage application unit 183 corresponds to an example of a focus adjustment control unit according to the present invention.

  The focus actuator 410 is used as follows.

  When the photographing mode is selected by the photographer, the subject light that has passed through the camera shake correction lens 201 and the photographing lens 110 is roughly read by the CCD 112, and low-resolution image data is generated in the A / D conversion unit 113. The The low resolution data passes through the input controller 130, the image signal processing unit 140, the video encoder 150, and the image display device 160, and the through image represented by the low resolution data is displayed on the liquid crystal panel 101 by the image display device 160.

  The low resolution data is also transmitted to the CPU 180. The CPU 180 transmits an applied voltage value for causing the focus actuator 410 to contract in a plurality of stages to the voltage application unit 183, and the voltage application unit 183 applies the voltage of the value transmitted from the CPU 180 to the focus actuator 410. As a result, the focus actuator 410 is contracted in a plurality of stages, and the rear lens 2012 is pulled to the back side as the focus actuator 410 contracts, so that the relative position between the rear lens 2012 and the front lens 2011 is adjusted in a plurality of stages. Is done. At this time, by measuring the capacitance of the focus actuator 410, the lens position of the rear lens 2012 can be detected, and the relative position between the rear lens 2012 and the front lens 2011 can be accurately controlled.

  The CPU 180 acquires the contrast of the subject based on the low resolution data acquired at each of the plurality of levels of applied voltages, and calculates the applied voltage value when the contrast is maximized. The calculated applied voltage value is transmitted to the voltage applying unit 183, and the voltage having the value transmitted from the voltage applying unit 183 to the focus actuator 410 is applied. As a result, the rear lens 2012 is moved to a position corresponding to the applied voltage, and the relative position between the rear lens 2012 and the front lens 2011 is adjusted to a focus position where the contrast is maximized.

  As described above, the camera shake correction lens 201 is adjusted to the focus position, and when the photographer presses the selection button 104 in FIG. Thus, according to the camera shake unit 400 of the present embodiment, camera shake can be corrected with high accuracy in the same procedure as the camera shake unit 200 of the first embodiment, and the size of the apparatus and the power consumption are significantly increased. You can focus on the subject securely.

  Above, description of 2nd Embodiment of this invention is complete | finished and 3rd Embodiment of this invention is described. Since the third embodiment of the present invention has substantially the same configuration as that of the second embodiment of the present invention, the same elements are denoted by the same reference numerals, and the description thereof is omitted. Only the differences between the two embodiments will be described.

  FIG. 10 is a cross-sectional view of the camera shake unit 500 of this embodiment as viewed from above.

  The camera shake unit 500 of the present embodiment is provided with a holding frame 501 that is restricted from moving in the direction intersecting the optical axis O and is movably supported in the optical axis direction. A lens 2011 is held. Further, the camera shake unit 500 includes a focus actuator 510 including two polymer actuators 511 and 512 instead of the stacked focus actuator 410 shown in FIG. One end is fixed to the housing 200 a and the other end is fixed to the holding frame 501. The focus actuator 510 corresponds to an example of a fourth drive unit referred to in the present invention.

  When a voltage is applied to the focus actuator 510, the focus actuator 510 tries to expand in accordance with the applied voltage. However, since both ends of the focus actuator 510 are fixed to the housing 200a and the holding frame 501, the focus actuator 510 bends and pulls the holding frame 501. Since the holding frame 501 is supported so as to be movable only in the optical axis direction, the holding frame 501 is moved in the optical axis direction by the bending stress of the focus actuator 510. As a result, the relative positions of the front lens 2011 and the rear lens 2012 are changed. Adjusted.

  Also in this embodiment, since the surface areas of the two polymer actuators 511 and 512 change according to the applied voltage, the lens position of the front lens 2011 can be detected based on the capacitance of the polymer actuators 511 and 512. High precision focus adjustment can be realized.

  Here, the example in which the camera shake correction unit of the present invention is applied to a mobile phone has been described above, but the camera shake correction unit of the present invention may be applied to a digital camera or the like.

  In the above description, an example of both the correction optical system and the focus adjustment optical system has been described. However, the focus adjustment optical system according to the present invention may use, for example, an imaging optical system.

1 is an external perspective view of a mobile phone to which an embodiment of the present invention is applied. It is a block diagram of the mobile telephone with which the camera shake unit was mounted | worn. It is a disassembled perspective view of the camera shake unit utilized conventionally. It is sectional drawing when the camera shake unit of 1st Embodiment is seen from the front. It is a figure for demonstrating the principle of operation of a polymer actuator. It is sectional drawing when the actuator for camera shake applied to a camera shake unit is cut | disconnected along the expansion-contraction direction. It is sectional drawing of the lens vicinity when the mobile phone with which the camera shake unit was mounted | worn is seen from the top. It is sectional drawing when the actuator for camera shake in 2nd Embodiment is cut | disconnected along the expansion-contraction direction. It is sectional drawing when the camera shake unit of 2nd Embodiment is seen from the top. It is sectional drawing when the camera shake unit of 3rd Embodiment is seen from the top.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Mobile phone 100a Case 101 Liquid crystal panel 102 Mouthpiece 103 1st transmission / reception part 103a 1st antenna 104 Selection button 105 Push button 106 Earpiece 107 Confirmation button 108 Power button 109 2nd transmission / reception part 109a 2nd antenna 110 Shooting lens 110a Magnet 111 Iris 112 CCD
113 A / D conversion unit 120 Interface unit 121 Microphone 122 Speaker 130 Input controller 140 Image signal processing unit 150 Video encoder 160 Image display device 170 Memory 180 CPU
181 Various switches 190 Media controller 300 Recording media

Claims (5)

A correction optical system for correcting blurring of an image formed by the imaging optical system;
A camera shake detection unit for detecting camera shake;
A frame,
A guide portion extending in a predetermined guide direction within a plane intersecting the optical axis of the imaging optical system;
A moving unit that supports the correction optical system, receives the application of force in the guiding direction, is guided by the guiding unit, and moves in the guiding direction with respect to the frame;
One end is fixed to the frame body that extends along the guide direction, and the other end with respect to the one end is fixed to the moving portion. A drive unit composed of an elastic member to be moved in the guide direction, and an electrode for applying a voltage to the elastic member;
By applying a voltage according to the detection result of the camera shake detection unit to the electrode and moving the moving unit to the telescopic member, the correction optical system is moved in the guide direction, and subject light caused by camera shake is generated. A camera shake correction control unit for correcting the shift ,
The elastic member is a tube-shaped polymer actuator sandwiched between two coil springs that contact the inner surface and the outer surface, respectively.
The camera shake correction unit according to claim 1, wherein the driving unit extends and contracts the polymer actuator by applying a voltage between the two coil springs . The correction optical system is supported by the moving unit so as to be movable in both a first direction and a second direction different from each other in the plane,
The guide portion includes a first guide portion and a second guide portion extending in the first direction and the second direction, respectively.
The moving unit supports the correction optical system so as to be movable in the second direction, and receives the application of force in the first direction and is guided by the first guiding unit in the first direction. A first moving unit that moves, and the correction optical system are movably supported in the first direction, and are applied to the second guide unit by receiving a force in the second direction. And a second moving part that moves in the direction of 2,
The drive unit extends along the first direction, is fixed to the frame body and the first moving unit, and moves in the first direction to move the first moving unit in the first direction. A member, a first electrode for applying a voltage to the first elastic member, the second electrode extending along the second direction, fixed to the frame and the second moving portion, and A second elastic member that moves the two moving parts in the second direction, and a second electrode for applying a voltage to the second elastic member,
2. The camera shake correction unit according to claim 1, wherein the camera shake correction control unit applies a voltage to both the first electrode and the second electrode.   A focus adjustment optical system that adjusts the focus of an image formed by the imaging optical system by moving in the optical axis direction;
  Extending in the optical axis direction of the focus adjustment optical system, one end is fixed to the frame, and the other end relative to the one end is fixed to the focus adjustment optical system, and expands and contracts in response to voltage application and release. A third drive unit comprising: a third stretchable member that moves the focus adjustment optical system in the optical axis direction; and a third electrode for applying a voltage to the third stretchable member;
  A focus adjustment control unit configured to adjust the focus by moving the focus adjustment optical system in the optical axis direction by applying a voltage to the third electrode to expand and contract the third expansion member. The camera-shake correction unit according to claim 1. The camera shake correction unit according to claim 3, wherein the third elastic member is formed by laminating a plurality of elastic members.   In an imaging device that performs imaging by capturing subject light incident via an imaging optical system,
  A correction optical system for correcting blurring of an image formed by the imaging optical system;
  A camera shake detection unit for detecting camera shake;
  A frame,
  A guide portion extending in a predetermined guide direction within a plane intersecting the optical axis of the imaging optical system;
  A moving unit that supports the correction optical system, receives the application of force in the guiding direction, is guided by the guiding unit, and moves in the guiding direction with respect to the frame;
  One end is fixed to the frame body that extends along the guide direction, and the other end with respect to the one end is fixed to the moving portion. A drive unit composed of an elastic member to be moved in the guide direction, and an electrode for applying a voltage to the elastic member;
  By applying a voltage according to the detection result of the camera shake detection unit to the electrode and moving the moving unit to the telescopic member, the correction optical system is moved in the guide direction, and subject light caused by camera shake is generated. A camera shake correction control unit for correcting the shift,
  The elastic member is a tube-shaped polymer actuator sandwiched between two coil springs that contact the inner surface and the outer surface, respectively.
  The imaging apparatus according to claim 1, wherein the driving unit is configured to expand and contract the polymer actuator by applying a voltage between the two coil springs.

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