JP2007334121A - Vibration correcting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the effect of electric noise on an imaging element, when a vibration correcting device is mounted on, for example, a portable apparatus. <P>SOLUTION: The vibration correcting device includes a housing 10a; a circuit board 22 fixed to the housing 10a; the imaging element 54 fixed to the circuit board 22; a lens barrel 53 holding lenses 51 and 52 comprising a photographic optical system that images on the imaging element 54; a vibration detecting part 21 that detects vibration applied to the housing 10a; a drive means that shakes the lens barrel 53 relative to the circuit board 22, based on the output of the vibration detecting part 21; and a conductive tension coil spring 56, disposed on the circuit board 22 and elastically supporting the lens barrel 53. The tension coil spring 56 is connected to the electrical ground of the circuit board 22. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a shake correction apparatus for preventing image deviation of a captured image due to camera shake by performing shake correction, and is particularly suitable for use in a portable device having a shooting function.

  With current cameras, all the important tasks for shooting, such as determining exposure and focusing, are automated, and there is very little chance of shooting failure even for those who are unskilled in camera operation.

  In recent years, a shake correction apparatus that prevents image shift of a shot image due to camera shake applied to the camera has been installed in many products, and the cause of a photographer's shooting mistake has almost disappeared. .

  Here, the shake correction apparatus will be briefly described. The camera shake at the time of photographing is a vibration of usually about 1 Hz to 10 Hz as a frequency. In order to enable shooting without image displacement even when the above-mentioned camera shake occurs at the time of shooting, the camera vibration due to camera shake is detected, and the lens is set in a direction to cancel the shake according to the detected value. Displace.

  For that purpose, it is firstly necessary to accurately detect camera shake, and secondly, it is necessary to correct a change in optical axis due to camera shake. In principle, camera shake is detected by mounting vibration detection means on the camera that detects acceleration, angular acceleration, angular velocity, angular displacement, and the like, and appropriately calculates the output for shake correction. Based on this detection information, a shake correction lens that decenters the photographic optical axis is driven to prevent image displacement.

  FIG. 12 is an external view of a digital compact camera. In the camera body 121, 121a is a release button, 121b is a mode dial (including a main switch), and 121c is a retractable strobe. This digital compact camera is equipped with a shake correction device and performs shake correction for camera vertical shake and horizontal shake indicated by arrows 122p and 122y with respect to the optical axis 120.

  Although not shown in FIG. 12, a liquid crystal monitor is provided on the back of the camera body 121 so that an image picked up by the image pickup device 154 (see FIG. 13) can be confirmed. The photographer can take a picture after confirming the composition of the photographed image on the liquid crystal monitor.

  FIG. 13 is a perspective view showing a part of the internal structure of the digital compact camera shown in FIG. Reference numeral 154 denotes an image sensor such as a CCD imager or a CMOS imager. Reference numeral 131 denotes a shake correction apparatus that drives the correction lens 130 freely in the directions of the arrows 132p and 132y to perform shake correction in the directions of the arrows 122p and 122y shown in FIG. Reference numerals 221p and 221y denote vibration detection means such as an angular velocity meter and an angular accelerometer that detect vibrations around the arrows 221a and 221b, respectively. Outputs of the vibration detection means 221p and 221y are converted into drive target values for the shake correction apparatus 131 via the calculation means 181p and 181y, and input to the shake correction apparatus 131.

  By the way, in recent years, downsizing of an image sensor has progressed, and it has come to be mounted even on a portable device such as a mobile phone. However, since the portable device is small and light, there is a problem that camera shake at the time of shooting increases. For this reason, countermeasures against image misalignment of captured images due to camera shake are a very important issue.

  Up to now, there has been proposed a shake correction function when a small portable device such as a mobile phone or a mobile device is provided with a photographing function. For example, Patent Document 1 discloses a configuration in which a movable portion including a lens, an image sensor, and a lens barrel that holds these lenses is swung.

JP 2005-173372 A

  In Patent Document 1 described above, a movable portion including a lens, an image sensor, and a lens barrel that holds these is configured to swing. When the image sensor is swung as described above, there is a problem that the size of the image sensor is increased and the connection of the image sensor to the circuit board becomes a driving load.

  In addition, when a shake correction device is mounted on a portable device, the image pickup device and the shake correction device must be arranged close to each other, and there is a possibility that the image pickup device may be affected by electrical noise.

  For example, when a coil spring is provided that elastically supports the lens barrel in order to suppress and rotate the optical axis direction, irregular reflection of electromagnetic waves may occur due to a so-called antenna effect that the coil spring picks up an electric field component. . And the output of an image pick-up element may be disturb | confused by the noise induced | guided | derived by this antenna effect.

  Further, when a current flows through the coil of the shake correction device, there is a possibility that the output of the image sensor close to the coil is disturbed due to the influence of electromagnetic waves emitted from the coil.

  The present invention has been made in view of the above points. For example, when a shake correction apparatus is mounted on a portable device, an object of the present invention is to alleviate the influence of electrical noise on an image sensor.

The shake correction apparatus of the present invention holds a casing, a circuit board fixed to the casing, an imaging unit fixed to the circuit board, and a lens constituting an imaging optical system that forms an image on the imaging unit. A lens barrel, vibration detection means for detecting vibration applied to the housing, drive means for swinging the lens barrel relative to the circuit board based on an output of the vibration detection means, A conductive elastic support member provided on a circuit board and elastically supporting the lens barrel is provided, and the elastic support member is grounded.
Another shake correction apparatus according to the present invention includes a housing, a circuit board fixed to the housing, an imaging unit fixed to the circuit board, and a lens constituting an imaging optical system that forms an image on the imaging unit. A lens barrel that holds the lens body, vibration detection means that detects vibration applied to the housing, and drive means that swings the lens barrel relative to the circuit board based on an output of the vibration detection means. The circuit board is characterized in that the image pickup means and an electric shield pattern disposed between a part of the drive means to which a drive current is supplied are provided.

  According to the present invention, for example, even when a shake correction apparatus is mounted on a mobile device, the influence of electrical noise on the image sensor can be reduced.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
(First embodiment)
FIG. 1 is a front view of a mobile phone 10 which is a mobile device according to the first embodiment of the present invention. The cellular phone 10 includes housings 10 a and 10 b that can be folded by a hinge 11. The housing 10b is provided with a sub-display 12 that displays the incoming status of incoming calls and mails and serves as a monitor for shooting in a folded state. The sub display 12 displays the time during standby. The housing 10b is provided with a display LED 13 for incoming calls and mails.

  2 is a cross-sectional view taken along the line AA in FIG. In the figure, reference numerals 10a, 10b, 11, 12, and 13 denote the above-described casing, hinge, sub-display, and display LED, respectively. Reference numeral 12a denotes a sub-display protection window for protecting the sub-display 12, and reference numeral 13a denotes an LED window for protecting the display LED 13.

  Reference numeral 20 denotes a main camera, and 20a denotes a camera protection window. Reference numeral 21 denotes a vibration detection unit.

  Reference numeral 22 denotes a circuit board fixed to the housing 10a, on which an operation pad 210 made of conductive rubber or the like, an IC 22a, or the like is mounted. The operation pad 210 is provided with a decorative plate 210a. The image sensor 54 of the main camera 20 is connected to the connector 20c on the circuit board 22 by a flexible circuit board 20b.

  Reference numeral 23 denotes a sub circuit board fixed to the housing 10b, on which an IC 23a is mounted.

  Reference numeral 24 denotes a main display, which is used as a monitor for games and shooting, together with the display of e-mails and telephone numbers. Reference numeral 24 a denotes a main display protection window for protecting the main display 24. Reference numeral 24 b denotes a flexible circuit board for connection of the main display 24, which is connected to a connector 24 c on the sub circuit board 23. Similarly, the sub display 12 is connected to the connector 12c on the sub circuit board 23 by the flexible circuit board 12b.

  Reference numeral 25a denotes an image sensor of the sub camera, 25b denotes an optical system for the sub camera, and 25c denotes a sub camera protection window. The sub-camera 25 is configured by the imaging element 25a and the optical system 25b.

  26 is a speaker when using the telephone, and 27 is a microphone. Reference numeral 28 denotes a battery serving as a power source, and 28a denotes a battery lid. Reference numeral 29 denotes an antenna.

  FIG. 3 is a rear view of the mobile phone 10 according to the present embodiment, and the housing 10a is provided with a camera protection window 20a and a battery lid 28a. The battery lid 28a is provided with a claw hook portion 28b for opening the battery lid 28a.

  FIG. 4 is a cross-sectional view of the cellular phone 10 in an opened state. In FIG. 4, only the main symbols are shown, and the symbols of the respective parts described in FIG. 2 are omitted. If the mobile phone 10 is in an open state, the video from the main camera 20 can be taken while being confirmed on the main display 24. In addition, by using the sub camera 25 and the main display 24, it is possible to perform a self-photographing or a videophone call.

  FIG. 5 is a detailed sectional view around the main camera 20. FIG. 6 is a front view of the vicinity of the main camera 20, and FIG. 7 is an enlarged front view of the circuit board 22 near the main camera 20. Note that members not directly related to the present invention are omitted in the drawing.

  As will be described below, in the present embodiment, the imaging element 54 is fixed to the circuit board 22, and the lens barrel 53 that holds the lenses 51 and 52 constituting the photographing optical system is swung with respect to the circuit board 22. Thus, the shake correction apparatus can be reduced in size.

  As shown in FIG. 5, lenses 51 and 52 constituting a photographing optical system having a common optical axis 50 are housed in a lens barrel 53 having an aperture 53a on the objective surface.

  In addition, an imaging element 54 as an imaging unit is fixed to the circuit board 22 so as to face the imaging optical system. As shown in FIG. 2, the image sensor 54 is electrically connected to the circuit board 22 by the flexible circuit board 20b and the connector 20c. Note that the image sensor 54 may be directly mounted on the circuit board 22.

  Next, the configuration of the driving means for swinging the lens barrel 53 with respect to the circuit board 22 will be described. As shown in FIG. 6, yokes 57 p and 57 y made of a ferromagnetic material are attached to the lens barrel 53 in the orthogonal direction. Permanent magnets 58p and 58y magnetized with a material such as neodymium are attracted and fixed to the yokes 57p and 57y, respectively. In FIG. 6, the yokes 57p and 57y are shown by outline only in order to illustrate the permanent magnets 58p and 58y.

  On the other hand, as shown in FIG. 7, position coils 59 p and 59 y facing the permanent magnets 58 p and 58 y on the lens barrel 53 side are fixed to the circuit board 22. In this embodiment, the coils 59p and 59y are fixed to the circuit board 22 by adhesion or the like, but the coils 59p and 59y may be printed coils integrally printed on the circuit board 22.

  With this configuration, when an electric current is passed through the coil 59p (59y), the lens barrel 53 is swung in two directions indicated by arrows 132p (132y) due to the electromagnetic action of the coil 59p (59y) and the permanent magnet 58p (58y). .

  In this case, as shown in FIG. 5, a slight gap is formed between the outer diameter portion 53c of the lens barrel 53 in the inner diameter portion 10c of the portion of the housing 10a facing the main camera 20. It has become. As a result, the amount of swing of the lens barrel 53 can be regulated, and the lens barrel 53 can be prevented from largely swinging due to a disturbance impact or the like, and damage to the lens barrel 53 can be prevented.

  Hall elements 510p and 510y as position detecting means are mounted at the centers of the coils 59p and 59y, and the position of the lens barrel 53 in the swinging direction is detected in relation to the opposing permanent magnets 58p and 58y. be able to.

  The circuit board 22 is provided with a tension coil spring 56 that elastically supports the lens barrel 53. As shown in FIG. 6, the tension coil springs 56 are arranged at three locations around the lens barrel 53 and are obliquely hung on the lens barrel 53. Thereby, an urging force that presses the lens barrel 53 against the circuit board 22 acts. Further, the tension coil spring 56 also serves as a rotation stopper for the lens barrel 53.

  Further, on the surface of the lens barrel 53 facing the circuit board 22, recesses 53 b are formed at three locations corresponding to the tension coil springs 56. Each concave portion 53 b is provided with a rolling ball 55, and the rolling ball 55 is interposed between the lens barrel 53 and the circuit board 22. As described above, the urging force that presses the lens barrel 53 against the circuit board 22 is applied by the tension coil spring 56, so that the rolling ball 55 does not come off the lens barrel 53. By providing the rolling balls 55 in this way, the lens barrel 53 is supported so as to be swingable with respect to the circuit board 22. In this case, as shown in FIG. 7, a metal pattern surface 60 such as a copper foil is provided at a position for receiving the rolling ball 55 so that the rolling ball 55 rolls smoothly. In addition, in the front view of FIG. 6, although the rolling ball 55 is not actually visible, arrangement | positioning is shown for description.

  Here, the tension coil spring 56 is electrically conductive, and an end portion thereof penetrates the circuit board 22 and is soldered to the back surface (soldering portion 56a), and is connected to the electrical ground of the circuit board 22. The tension coil spring 56 may be fixed to the circuit board 22 with a conductive adhesive or the like. By assembling the tension coil spring 56 so as to be connected to the ground of the circuit board 22 in this way, the tension coil spring 56 and the ground of the circuit board 22 have the same potential, and unnecessary radiation from the tension coil spring 56 can be suppressed. It is. Therefore, even when a shake correction apparatus is mounted on a portable device, the influence of electrical noise on the image sensor 54 can be reduced.

  Further, in the mobile phone 10 of the present embodiment, the vibration detection unit 21 is mounted on the surface opposite to the surface on which the imaging element 54 of the circuit board 22 is fixed. Specifically, the vibration detection unit 21 includes a two-axis detection vibration gyro that detects a rotational angular velocity around an arrow 21a and around an arrow 21b orthogonal thereto. Of course, although one vibration detection unit 21 is illustrated as a vibration gyro configuration that detects rotation about the two axes, two vibration detection gyros with one axis detection may be arranged in the detection direction. As described above, by mounting the vibration detection unit 21 on the surface opposite to the main camera 20, the mounting area can be used effectively, and the whole can be made compact.

  FIG. 8 is a block diagram showing the configuration of the shake correction apparatus. The angular velocity detection of the vibration gyro (which is distinguished from 21p and 21y for detecting the angular velocity in the biaxial direction), which is the vibration detection unit 21, is input to the signal processing units 81p and 81y. In the signal processing units 81p and 81y, the angular velocity signal is subjected to integration processing and converted into an angle signal, and processing such as DC component removal and panning countermeasures is performed and converted into a shake correction target value. Based on the obtained shake correction target value, a current is applied to the coils 59p and 59y, and the lens barrel 53 starts swinging for shake correction. In this case, since a known feedback control of a negative feedback (broken line 83) configuration that detects the oscillation of the lens barrel 53 by the Hall elements 510p and 510y and supplies current to the coils 59p and 59y is constructed. 53 is driven accurately according to the shake correction target value.

(Second Embodiment)
FIG. 9 is a detailed sectional view around the main camera 20 in the second embodiment. A difference from the first embodiment (FIG. 5) is that the wire 100 elastically supports the lens barrel 53. The wire 100 is a conductive elastic support member such as phosphor bronze.

  Further, the rolling ball is eliminated, and the concave surface 53b of the lens barrel 53 and the pattern surface 60 for receiving the rolling ball on the circuit board 22 are eliminated.

  Here, the end of the wire 100 penetrates the circuit board 22 and is soldered to the back surface (soldering part 100a), and is connected to the electrical ground of the circuit board 22. The wire 100 may be fixed to the circuit board 22 with a conductive adhesive or the like. As described above, by assembling the wire 100 so as to be connected to the ground of the circuit board 22, the wire 100 and the ground of the circuit board 22 have the same potential, and unnecessary radiation from the wire 100 can be suppressed. Therefore, even when a shake correction apparatus is mounted on a portable device, the influence of electrical noise on the image sensor 54 can be reduced.

(Third embodiment)
FIG. 10 is a detailed cross-sectional view around the main camera 20 in the third embodiment. The difference from the first embodiment (FIG. 5) is that the tension coil spring 111 that elastically supports the lens barrel 53 is not directly fixed to the circuit board 22, but a support member (L-shaped pin 110) that hooks the tension coil spring 111. ) To the circuit board 22 (soldering part 110a).

  The conductive L-shaped pin 110 is connected to the electrical ground of the circuit board 22, and the conductive tension coil spring 111 has the same potential as the L-shaped pin 110 by contacting the L-shaped pin 110. Of course, the L-shaped pin 110 may be fixed to the circuit board 22 with a conductive adhesive or the like. Thus, by assembling the L-shaped pin 110 so as to be connected to the ground of the circuit board 22, the L-shaped pin 110 and the tension coil spring 111 and the ground of the circuit board 22 are at the same potential, and the L-shaped pin 110 and the tension coil spring. Unwanted radiation from 111 can be suppressed. Therefore, even when a shake correction apparatus is mounted on a portable device, the influence of electrical noise on the image sensor 54 can be reduced.

(Fourth embodiment)
FIG. 11 is an enlarged front view of the circuit board 22 in the vicinity of the main camera 20 in the fourth embodiment. The difference from the first embodiment (FIG. 7) is that an electric seal pattern 200 is provided on the circuit board 22.

  On the circuit board 22, ground patterns 200p and 200y as electric shields are arranged between the image sensor 54 and the coils 59p and 59y through which the drive current flows. Thereby, even when driving power is supplied to the coils 59p and 59y in order to drive the shake correction apparatus, noise is prevented from being generated in the image sensor 54 due to this power signal (for example, a pulse signal by PWM driving). Is something that can be done. Therefore, even when a shake correction apparatus is mounted on a portable device, the influence of electrical noise on the image sensor 54 can be reduced.

  As mentioned above, although this invention was demonstrated with various embodiment, this invention is not limited only to these embodiment, A change etc. are possible within the scope of the present invention. The dimensions, materials, shapes, relative arrangements, and the like of the components described in the above embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Absent.

  Although the description has been continued with the shake correction device in the portable device such as the mobile phone 10 as an example, the shake correction device of the present invention can be reduced in size, and thus is not limited to the portable device, and is not limited to the portable device. It is also installed in cameras, surveillance cameras, web cameras and the like.

1 is a plan view of a mobile phone according to a first embodiment. It is AA sectional drawing of FIG. 1 is a rear view of a mobile phone according to a first embodiment. It is sectional drawing in the state with the open cellular phone concerning a 1st embodiment. It is a detailed sectional view around the main camera in the first embodiment. It is a front view of the main camera vicinity in 1st Embodiment. It is an enlarged front view of the vicinity of the main camera of the circuit board in the first embodiment. It is a block diagram which shows the structure of a shake correction apparatus. It is a detailed sectional view around the main camera in the second embodiment. It is a detailed sectional view around the main camera in the third embodiment. It is an enlarged front view near the main camera of the circuit board in the fourth embodiment. 1 is an external view of a digital compact camera equipped with a shake correction device. It is a perspective view which shows a part of internal structure of a digital compact camera.

Explanation of symbols

10a: housing 10b: housing 20: main camera 21: vibration detection unit 22: circuit board 53: lens barrel 54: imaging element 55: rolling ball 56: tension coil spring 58p: permanent magnet 58y: permanent magnet 59p: coil 59y : Coil 100: Wire 110: L-shaped pin 111: Coil spring 200p: Ground pattern 200y: Ground pattern 510p: Hall element 510y: Hall element

Claims (16)

A housing,
A circuit board fixed to the housing;
Imaging means fixed to the circuit board;
A lens barrel that holds a lens constituting a photographing optical system that forms an image on the imaging means;
Vibration detecting means for detecting vibration applied to the housing;
Driving means for swinging the lens barrel relative to the circuit board based on the output of the vibration detecting means;
A conductive elastic support member provided on the circuit board and elastically supporting the lens barrel;
The shake correction apparatus, wherein the elastic support member is grounded.   The shake correction apparatus according to claim 1, wherein the elastic support member is directly connected to a ground of the circuit board.   The shake correction apparatus according to claim 1, wherein the elastic support member is connected to a ground of the circuit board via a conductive support member.   The shake correction apparatus according to claim 1, wherein the elastic support member is a coil spring.   5. The shake correction apparatus according to claim 1, wherein the driving unit swings the lens barrel in a direction substantially orthogonal to the optical axis of the photographing optical system.   The said drive means rocks the said lens barrel with respect to the said circuit board by the relative electromagnetic effect | action of the said circuit board and the said lens barrel, The any one of Claims 1-5 characterized by the above-mentioned. Shake correction device.   The drive means swings the lens barrel with respect to the circuit board by electromagnetic action of a coil provided on the circuit board and a permanent magnet provided on the lens barrel and facing the coil. The shake correction apparatus according to any one of claims 1 to 6.   The driving means swings the lens barrel with respect to the circuit board by an electromagnetic action of a permanent magnet provided on the circuit board and a coil provided on the lens barrel and facing the permanent magnet. The shake correction apparatus according to claim 1, wherein the shake correction apparatus is characterized in that   9. The shake correction apparatus according to claim 7, further comprising a yoke that forms a magnetic path of the permanent magnet.   The shake correction apparatus according to claim 1, further comprising an elastic member that urges the lens barrel toward the circuit board.   The shake correction apparatus according to claim 1, further comprising a swing restricting portion that restricts a swing amount of the lens barrel by the driving unit.   12. A rolling ball interposed between the lens barrel and the circuit board and supporting the lens barrel so as to be swingable with respect to the circuit board. The shake correction device according to item.   The shake correction apparatus according to claim 12, wherein the circuit board is provided with a pattern surface that receives the rolling ball.   The shake correction apparatus according to claim 1, further comprising a position detection unit that is provided on the circuit board and detects a position of the lens barrel in a swinging direction.   The shake correction apparatus according to claim 1, wherein the vibration detection unit is provided on a surface of the circuit board opposite to a surface on which the imaging unit is fixed. A housing,
A circuit board fixed to the housing;
Imaging means fixed to the circuit board;
A lens barrel that holds a lens constituting a photographing optical system that forms an image on the imaging means;
Vibration detecting means for detecting vibration applied to the housing;
Driving means for swinging the lens barrel relative to the circuit board based on the output of the vibration detecting means;
A shake correction device, comprising: the imaging unit provided on the circuit board; and an electric shield pattern disposed between a part of the driving unit to which a driving current is supplied.

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