JP3956787B2 - Imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an imaging apparatus used for a digital camera, and more particularly to an imaging apparatus capable of performing camera shake correction by driving an imaging unit.
[0002]
[Prior art]
  Active image stabilization technology that moves all or part of the optical system so as to correct the optical axis shift due to blurring includes a type that swings the correction optical system, a type that swings the entire optical system, and an image sensor. There are roughly three types of swinging types. However, those that oscillate the entire optical system have the problem that not only the mass of the oscillating member is large and a large amount of energy is required, but also the oscillation volume becomes large and the entire apparatus becomes large. Rarely used. In addition, there is a problem in that the one that swings the correction optical system has many design restrictions due to optical sensitivity, and the lens type to be applied is limited.
[0003]
  On the other hand, for example, a device that oscillates an image sensor disclosed in Japanese Patent Laid-Open Nos. 9-116910 and 6-46314 has few design restrictions due to optical sensitivity and can be applied to all lenses. There are many advantages such as various variations and cost savings.
[0004]
  However, this type has a problem that the higher the number of pixels, the more severe the movement error sensitivity, and the difficulty of processing the flatness of the movement plane and the substrate around the image sensor. That is, it is difficult to take a dust-proof structure because the substrate arrangement and the moving area of the image sensor are ensured and a high-accuracy position detection device is required, and it is difficult to completely seal the image sensor. Therefore, dust such as dust enters and adheres to the surface of the image sensor, and there is a problem that these dust is reflected in a photograph at the time of photographing.
[0005]
  In the conventional camera shake prevention mechanism that swings the image sensor, the image pickup surface of the image sensor is covered with a transparent body, and the area where dust adheres is kept away from the image pickup surface, thereby reducing the problem of dust reflection. Exists. However, with this technology, the surface of the transparent body, which is the surface to which dust adheres, cannot be constructed far enough away from the imaging surface to solve the problem of dust reflection. It was insufficient.
[0006]
  That is, in the above-mentioned type of imaging apparatus, since the imaging unit is configured so that the imaging element can arbitrarily move on a plane parallel to the imaging surface, it is not possible to fix and seal the imaging element directly on the lens barrel. It is difficult and a gap is formed between the lens barrel and the imaging surface. Also, since it is difficult to completely eliminate assembly errors and component molding errors at the stage of assembling the imaging unit to the optical unit, the light that adjusts the tilt of the imaging unit and the lens back with respect to the optical unit after assembly. It is common to perform axis adjustment. In an imaging apparatus that performs this optical axis adjustment, in order to adjust the position between the imaging unit and the optical unit, it is necessary to provide a predetermined gap between them. Therefore, in the type of image pickup apparatus that swings the image pickup device, there is a problem that dust enters through these gaps and the dust adheres to the imaging surface.
[0007]
[Problems to be solved by the invention]
  Therefore, the technical problem to be solved by the present invention is to provide an image pickup apparatus that keeps the surface to which dust adheres from the image pickup surface as much as possible and makes the problem of dust reflection as inconspicuous as possible.
[0008]
[Means for solving the problems and actions / effects]
  In order to solve the above technical problem, the present invention provides an imaging apparatus having the following configuration.
[0009]
  The imaging apparatus includes an optical unit including one or a plurality of photographing lenses and a lens barrel that houses the photographing lenses, an imaging unit that captures subject light, and the imaging unit on a plane perpendicular to the subject light in an arbitrary direction. An image pickup unit having a camera shake correction function including a moving means for moving the image pickup device and a position detection means for detecting the position of the image pickup means, and the optical unit and the image pickup unit are connected so that the optical axis can be adjusted. is there. Further, the image pickup unit further includes a storage unit that hermetically encloses the image pickup unit, the moving unit, and the position detection unit of the image pickup unit, and the image pickup unit has an optical path opening for transmitting the subject light to the image pickup unit. The optical unit is connected so as to be optically sealed.
[0010]
  In the above configuration, the imaging apparatus includes an optical unit that includes a photographic lens and a lens barrel, and an imaging unit that is connected to the optical unit. When the optical unit includes a plurality of photographing lenses, the optical unit may be configured to change the focal length. In addition, as will be described later, since the present imaging apparatus performs camera shake correction by driving the imaging unit, there are few design restrictions related to the optical sensitivity of the optical unit, and optical units having various configurations can be used. it can.
[0011]
  The image pickup unit is configured such that the image pickup means can be moved so as to correct blur during shooting. The moving means and position detecting means, which are means for moving the image pickup means and the image pickup means by an appropriate amount in the image pickup unit, are enclosed in the storage means and sealed. The imaging unit includes an optical path opening for allowing subject light to reach the imaging means.
[0012]
  The imaging unit and the optical unit adjust the mounting position and inclination of the imaging unit so that the subject light from the optical unit properly reaches the imaging unit, the opening of the optical unit and the imaging unit optical path opening face each other. It arrange | positions so that an optical axis adjustment can be performed. Therefore, a slight gap is generated between the optical unit and the imaging unit, and dust such as dust enters through the optical path opening. In order to prevent this, both are connected so that the optical path opening is sealed.
[0013]
  Here, optically sealing the optical path opening means that dust does not reach the optical path opening through the gap between the optical unit and the imaging unit. In other words, dust is prevented from entering the subject light through a gap between the optical unit and the imaging unit. Specifically, for example, (1) the gap between the optical unit and the imaging unit is sealed, or (2) a large cover attached to the rear end of the optical unit is used as a storage means, and imaging is performed in the lumen of the cover. Examples include a configuration in which the entire imaging unit including the optical path opening is completely housed and sealed, as well as the unit imaging means, moving means, and position detection means. On the other hand, the structure that simply covers the optical path opening and covers the optical path opening and seals the optical path opening, because dust reaches the surface of the transparent body through the gap between the optical unit and the imaging unit, The optical path opening in the present invention is excluded from the configuration for optically sealing.
[0014]
  According to the above configuration, the imaging unit has no problem of intrusion of dust or the like because each means for moving the imaging element is accommodated and sealed in the accommodation means. In addition, since each means for moving the imaging means is present inside the unit, regardless of the connection with the optical unit,loadTherefore, it is possible to realize a free movement with little movement, and it is possible to lighten each means for movement.
[0015]
  Furthermore, the light that becomes a problem for optical axis adjustmentRoadIn order to properly prevent dust from entering the opening for use in the connection between the imaging unit and the optical unit,RoadOptically seal the opening. Therefore, the imaging apparatus not only prevents the intrusion of dust from the imaging unit side in the optical axis-corrected imaging apparatus, but also optically controls the imaging means against the invasion of dust from the optical unit side. Dust does not enter the unit closer to the photographic lens. Therefore, it is possible to greatly reduce the problem of dust reflection.
[0016]
  Specifically, the imaging apparatus of the present invention can be configured in various aspects as follows.
[0017]
  Preferably, the position detection means includes a light detector, and the storage means is formed of a light non-transmissive member.
[0018]
  In the above configuration, by using a non-contact photodetector for detecting the position, wiring can be simplified and position detection with high accuracy can be performed. In addition, since the storage means does not transmit light, it is possible to prevent the disturbance of the photodetector due to external light and perform highly accurate position detection without imposing a load on the movement of the imaging means.
[0019]
  Preferably, the optical unit has a photographic lens that is always fixed so as to cover the imaging unit side opening of the lens barrel.
[0020]
  In general, the lens barrel is subject lightButAn object-side opening for incident and an image-unit-side opening for emitting object light are provided. In the above configuration, since the photographic lens is always fixed so as to cover the imaging unit side opening and does not move, for example, dust such as abrasion powder from an actuator used for focusing or the like passes through the imaging unit side opening. Intrusion into the optical path opening is prevented. That is, these dusts do not adhere closer to the image pickup means than the surface of the photographing lens provided in the image pickup unit side opening, and the problem of dust reflection can be reduced.
[0021]
  Preferably, the imaging apparatus uses a ring-shaped elastic member having a lumen having a larger dimension than the optical path opening and the imaging unit side opening of the lens barrel, and the optical path opening and the The optical path opening is sealed by sandwiching the elastic member between the optical unit and the imaging unit so that the imaging unit side opening of the lens barrel is disposed.
[0022]
  In the above configuration, the elastic member is a cylindrical member that covers the periphery of the optical path opening and the imaging unit side opening of the lens barrel. The elastic member is made of an elastic material such as rubber, and is optically sealed between the optical path opening and the imaging unit side opening of the lens barrel by being sandwiched between the optical unit and the imaging unit. In addition, the elastic member can be deformed and maintain high sealing performance between the two units even when the inclination is adjusted in the optical axis adjustment of the optical unit and the imaging unit.
[0023]
  Preferably, at least a part of the storage unit is configured by a substrate for processing a signal output from the imaging unit.
[0024]
  In the above configuration, by using the substrate as a part of the housing member, the imaging unit can be grounded through the substrate, and the imaging unit can be downsized.
[0025]
  In addition, since the image pickup means is driven, it is preferable that electrical connection with the image pickup means be made by a flexible substrate so that the drive of the image pickup means can be absorbed. In this case, the hole provided in the substrate for allowing the flexible substrate to pass is preferably a sealed structure, and a sealing member such as a tape is attached to the hole for sealing.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of an imaging apparatus according to the present invention will be described with reference to the drawings.
[0027]
  Of the present inventionImaging device10As shown in FIG.CombinedIt is mounted on the digital camera 1 and used. The imaging apparatus 10 includes an optical unit A composed of a plurality of lenses 4 and a lens barrel 3 and the optical unit.AImage sensor used in connection with15And an imaging unit B having a camera shake correction function. As will be described later, the optical unit A includes a plurality of lenses.4The focal length can be changed by moving. As indicated by an arrow 5 in FIG. 1, the image pickup unit B has an image pickup element when the digital camera 1 is shaken during shooting and the optical axis of the optical unit A is deviated from the position indicated by L in FIG. 1.15Is moved as indicated by an arrow 6 to correct the deviation of the optical axis.
[0028]
  FIG. 2 is an exploded perspective view of the imaging apparatus 10. FIG. 3 shows the imaging apparatus shown in FIG.10Sectional drawing which cut | disconnected by II cross section is shown. FIG. 4 shows the imaging apparatus shown in FIG.10Sectional drawing which cut | disconnected by II-II cross section is shown. FIG. 5 shows the imaging apparatus shown in FIG.10Sectional drawing which cut | disconnected this by the III-III cross section is shown.
[0029]
  First, the imaging unitBIt explains from. The imaging unit B includes a base member 11 serving as a base, and the base member11The first stage 13 moves in the horizontal direction (hereinafter, this direction is referred to as the X-axis direction), and the direction perpendicular to the movement direction (X-axis direction) of the first stage 13 (hereinafter, the Y-axis). The second stage 12 moving to the direction), and the second stage12Image sensor 15 fixed to the base, and base member11First and second stage fixed to12, 13And a PSD holder 14 equipped with a position detection element (hereinafter referred to as PSD) for detecting the amount of movement of.
[0030]
  The base member 11, the first stage 13, the second stage 12, and the PSD holder 14 that support the image pickup device 15 so as to be swingable include an image pickup device 15 (a first substrate that processes information from the image pickup device).17including. ) Around the bottom surface of the lens barrel 3 and the outer space of the image sensor 15.
[0031]
  The base member 11 is a plate provided substantially perpendicular to the optical axis L direction (hereinafter referred to as the Z-axis direction), and is a metal frame 23 having a large hole 24 for the optical axis at the center. The frame 23 of the base member 11 has a PSD holder fixing hole 25 for fixing the PSD holder 14, a lens barrel fixing hole 26 for fixing the base member 11 to the lens barrel 3, and a base member11And the first stage13Press spring suspended between55A pressing spring hook 27 is provided for fixing the spring.
[0032]
  As shown in FIGS. 2 and 3, in order to connect the imaging unit B to the optical unit A so that the position (turning and lens back) with respect to the lens barrel 3 can be adjusted, the base member 11 includes the lens barrel 3. The fixing screws 33 and the adjusting springs 21 are fixed to the three fixing portions 20 provided at three locations around the outer periphery of each of the fixing members 20. The distance and inclination between the base member 11 and the bottom surface of the lens barrel 3 can be adjusted by the adjustment spring 21 used for the fixing unit 20, and as a result, the optical axis between the optical unit A and the imaging unit B can be adjusted. it can.
[0033]
  Between the lens barrel 3 and the base member 11, a rubber sealing material 22 for absorbing intrusion of dust such as dust from the gap 100 between them while absorbing the change in the distance between them. Is placed. The sealing material 22 is a ring-shaped member having a larger dimension than the large hole 24 of the base member 11 and the imaging unit side opening 86 of the lens barrel 3. The sealing material 22 is sandwiched between the base member 11 and the bottom surface of the lens barrel 3 so that the large hole 24 and the imaging unit side opening 86 of the lens barrel 3 are disposed in the inner cavity thereof.
[0034]
  A rod support arm 29 and a positioning arm (not shown) are erected on the base member 11 in the Z-axis direction. The rod support arm 29 is a first actuator having a configuration in which the piezoelectric element 57 is fixed to the end of the vibration transmitting rod 28 and the weight 30 is fixed to the other end of the piezoelectric element 57.59Is provided. First actuator59In the state in which the weight 30 is in contact with the positioning arm, both ends of the vibration transmission rod 28 are rod support arms in the direction in which the vibration transmission rod 28 extends in the X-axis direction.29To be fixed to the base member 11. For adhesion between the rod support arm 29 and the vibration transmission rod 28, it is preferable to use an adhesive such as a silicon adhesive that remains elastic after curing. For bonding between the positioning arm and the weight 30, a soft rubber-based or silicon-containing adhesive is preferably used.
[0035]
  As shown in FIG. 4, the two rod support arms 29 of the base member 11 are provided with protrusions 84 extending in the Z-axis direction on the upper surfaces thereof. As will be described later, the protrusion 84 is fitted into the movement restriction hole 52a of the first stage 13 during assembly.
[0036]
  The first stage 13 is disposed downstream of the base member 11 in the optical axis direction (Z-axis direction). The first stage 13 is composed of an aluminum rectangular frame 52 provided with an opening 51 for accommodating the second stage 12 in substantially the same plane. The first stage 13 includes a first rod contact portion 53 that contacts the vibration transmission rod 28 of the first actuator 59 fixed to the base member 11, and a second stage described later.12A pressing spring hook 56 for locking the pressing spring 55 between the second rod contact portion 54 that contacts the vibration transmission rod 47 of the second actuator 44 fixed to the pressing spring hook 27 of the base member 11. And movement restriction hole52aWith.
[0037]
  First rod contact part53The first actuator 59 is slidable along the vibration transmission rod 28 by holding the vibration transmission rod 28 of the first actuator 59 together with the cap 32 and the spring 31 which are separate members.59To join. Cap 32 has one end at the first stage13The first stage is brought into contact with the vibration transmission rod 28 at the center and pulled by the holding spring 31 at the other end.13First rod contact part53Fixed to. The contact pressure between the cap 32 and the vibration transmission rod 28 is about twice the force of the holding spring 31. The clamping spring 31 is a torsion coil spring. The sandwiching spring 31 spans both arms and the central arc portion between the two hooks of the cap 32 and the spring hook of the first stage 13.
[0038]
  Movement restriction hole52aIs loose with the protrusion 84 at the tip of the rod support arm 29 of the base member 11 as described above.Fitting(See FIG. 4). The movement restriction hole 52a is a long hole extending in the movement direction (X-axis direction) to determine the movement amount of the first stage 13, and is the first stage.13In the short side direction (Y-axis direction) so that can move only in the X-axis directionFittingThe movement is restricted at both ends. Further, the vibration transmission rod 28 and the first stage 13 are connected to the movement restriction hole.52aAre prevented from moving (dropping out) in the short side direction (Y-axis direction).
[0039]
  As shown in FIG. 5, the first stage 13 is fixed to the base member by the pressing springs 55 provided on the pressing spring hooks 27 and 56 respectively provided on the base member 11 and the first stage 13 during assembly.11The first stage 13 is prevented from rotating around the vibration transmission rod 28 of the first stage 13.
[0040]
  The second stage 12 is a box 40 made of a conductive resin having an opening 41 at the bottom, and holds the imaging element 15, the heat radiating plate 16, the low-pass filter 65, and the second actuator 44. The heat radiating plate 16 is in contact with the back side of the image pickup device 15 where the image pickup surface is not provided, so that the second stage12The second stage so as to cover the opening defined by the peripheral wall 4012Fixed to. The image sensor 15 and,Image sensor15A low-pass filter 65 located in close contact with a gap frame beforeWhenIs pressed against the heat radiating plate 16 by a contact spring from the front.
[0041]
  The second stage 12 holds the second actuator 44. The second actuator 44 is provided on the side portion of the box 40.rodThe support arm 45 is bonded and held. Tip and end of vibration transmission rod 47 (piezoelectric element58Side) the two rod support arms of the second stage 1245The second stage is also fitted to the shaft.12The weight 46 is bonded to the second stage 12 with the weight 46 in contact with the positioning surface 45a (see FIG. 3) provided on the second stage 12. For adhesion, the vibration transmission rod is the same as the adhesion of the first actuator 59 described above.47Adhesives that remain elastic after curing, such as silicone adhesive, weights46For this contact, a soft rubber-based or silicon-containing adhesive is preferably used.
[0042]
  The second actuator 44 of the second stage 12 is sandwiched between the second rod contact portion 54 of the first stage 13 and the cap 48. As a result, the second stage 12 is frictionally coupled in a state where the second stage 12 is disposed in the opening 51 of the first stage 13. A clamping spring 49 is used to fix the second rod contact portion 54 and the cap 48. One end of the cap 48 is locked to the second rod contact portion 54, the center portion is in contact with the vibration transmission rod 47, and the other end is pulled by the holding spring 49. The contact pressure between the cap 48 and the vibration transmission rod 47 is about twice that of the clamping spring 49 used. The clamping spring 49 is a torsion coil spring similar to that used for the first actuator 59. The clamping spring 49 includes two hooks of the cap 48 and the first stage.13Both ends are fixed between the spring hooks of the second rod contact portion 54 so as to span the end portion and the center of the straight portion.
[0043]
  The second stage 12 has a metal direction reference portion 42 at a part thereof. The direction reference part 42 is in contact with the base member 11 and the first stage 13 through hard balls 43 on the front and back sides thereof. Since the pressing spring 55 is applied between the first stage 13 and the base member 11, the two stages 12 and 13 are vibration transmission rods that are frictionally coupled to each other.28, 47Rotation around is suppressed.
[0044]
  As shown in FIGS. 3 to 5, a first substrate 17 is provided on the back surface of the heat radiating plate 16. As for the image pick-up element 15, the terminal part 69 is a through-hole of the heat sink 1668And disposed on the first substrate 17. On the back side of the first substrate 17, in order to detect the position of the image sensor 15, a holder 70 containing two infrared LEDs 82X and 82Y, an image sensor driver, and an image sensor15Image sensors such as preamplifiers, color separation circuits, white balance adjustment circuits, analog processing circuits for processing photoelectric signals from15A part of the image signal output circuit is mounted.
[0045]
  The two infrared LEDs 82X and 82Y are held by the holder 70 such that the moving direction (rod) to be detected is orthogonal to the light source. The holder has slits 71X and 71Y LED82X, 82YEach LED 82X, 82YThe light emitted from is converted into a linear light source by passing through the slits 71X and 71Y. Each LED82X, 82YIs configured to be parallel to the first substrate 17 (moving plane) and not bulky in the imaging optical axis direction. Further, the slits 71X and 71Y are arranged on the outer periphery of the heat radiating plate 16 (first substrate envelope), and most of the LED optical path length passes through the heat radiating plate 16 (first substrate envelope).
[0046]
  The first substrate 17 is connected to a flexible substrate 67 that connects the image sensor 15 and the LEDs 82X and 82Y to the second substrate 18. As shown in FIG. 7, the flexible substrate 67 is connected not only to the first substrate 17 but also to the heat radiating plate 16 to ground the heat radiating plate 16. Specifically, the flexible substrate 67 is provided with a branch portion 87 in the vicinity of the terminal 88 connected to the first substrate 17, and the branch portion 87 has a through hole provided in the first substrate 17. It passes through and is connected to the heat sink 16 that exists underneath. As a result, the second stage 12, the hard sphere 43, and the base member 11 that are in contact with the heat sink 16 are also grounded. The flexible substrate 67 is once bent forward in the optical axis direction immediately after exiting the first substrate 17 in the horizontal direction, folded back in the vicinity of the base member 11, and then bent again in the horizontal direction at the position of the second substrate 18, Connected to the second substrate 18.
[0047]
  The PSD holder 14 is a base member11And the first stage 13, the second stage 12, and the image sensor 15 (including the heat sink 16 and the substrate 17).allThe second stage is fixed to the base member 11 so as to surround the second stage.12Two elements (first and second PSDs 62X and 62Y) for detecting the amount of movement are mounted. The light receiving surface of each PSD 62X, 62Y is a second stage by a slit that extends horizontally to the XY plane provided in the placement portions 61X, 61Y.12It is orthogonal to the luminous flux of the upper two LEDs 82X and 82Y. As shown in FIG. 4, the PSD holder14A projection 83 is provided on the inner wall so as to cover a part of the first stage 13 from the PSD holder 14 to prevent the first stage 13 from falling off in the optical axis direction.
[0048]
  The second substrate 18 is located on the back surface of the imaging surface, and is fixed to the PSD holder 14 so as to cover the back opening of the PSD holder 14, and the first substrate17And a flexible substrate 67. That is, the base member 11, the PSD holder 14, and the second substrate 18 have a structure in which the imaging element 15 and its driving mechanism are hermetically sealed except for the optical path and the moving space.
[0049]
  The second substrate 18 includes a circuit for processing a signal from the image sensor 15 or the first substrate 17 and a PSD.62X, 62Y2nd stage from12And a circuit for controlling two linear actuators from a gyro circuit. Second substrate18Two gyro signals whose detection directions are orthogonal to each other are input from a gyro substrate (not shown). This second substrate18Outputs a linear actuator control signal and a processed image sensor signal.
[0050]
  Next, the optical unit A will be described. The optical unit A is configured by housing a plurality of photographing lenses 4 in a lens barrel 3. FIG. 6 shows an optical unit according to the first embodiment.APhotographic lens used for4FIG. The optical unit A changes the focal length or adjusts the focus by moving the photographing lenses 4b to 4d of components other than the fourth component 4a located at the rearmost part among the plurality of components 4a to 4d in the optical axis direction. It is configured to be able to. 6A is a lens configuration diagram on the wide-angle side, and FIG. 6B is a lens configuration diagram on the telephoto side.
[0051]
  As shown in FIG. 6, in the optical system according to this embodiment, the last lens 4a is always fixed. Therefore, as shown in FIGS. 3 to 5, the photographing unit of the lens barrel 3 is used.BThe fourth component photographing lens 4 a can be fixed so as to cover the opening 86 on the side. Accordingly, dust such as dust existing in the lens barrel 3 covers the opening 86 of the lens barrel 3 by the photographing lens 4a.BCannot move to the side. Therefore, even when dust is attached, the distance to the surface of the photographic lens 4a is far from the imaging surface of the image sensor 15, so that the dust image becomes inconspicuous.
[0052]
  Next, the operation of the imaging apparatus according to the present embodiment will be described. FIG. 8 is a block diagram showing an electrical structure of the drive control circuit of the camera shake correction imaging apparatus according to the present embodiment.
[0053]
  The control circuit is the camera body2That is, comprehensive control of PSDs 62X and 62Y that detect the position of the gyro element 90 that detects the blur 5 of the optical axis L incident on the lens barrel 3 and outputs an angular velocity signal and the position of the second stage 12 (imaging element 15). And a microcomputer 102 that calculates a movement amount and a presence position based on an input signal and a drive circuit 104 that generates a drive pulse of a predetermined frequency based on a drive signal from the microcomputer. Drive pulses generated from the drive circuit are first and second actuators.59,44Output to the actuator59, 44The first and second stages 12 and 13 move along.
[0054]
  The gyro element 90 is,mirrorWhen it is fixed to the body 3 and the camera body is shaken as indicated by an arrow 5, the angular velocity in the biaxial direction (X-axis direction, Y-axis direction) is detected and output to the microcomputer 102.
[0055]
  When the angular velocity signal is input from the gyro element 90, the microcomputer 102 calculates the moving amount and moving speed of the image due to the blur on the imaging element (on the imaging plane) from the focal length signal of the optical system. A supply voltage of a predetermined frequency applied to the two linear actuators is determined from the calculated moving speed and the position of the second stage 12 (image sensor 15). That is, the microcomputer 102 is based on the position where the second stage 12 (imaging element 15) currently calculated based on the signals input from the PSDs 62X and 62Y and the angular velocity signal input from the gyro element 90. Then, the position where the image sensor 15 should be originally is calculated, the difference from the current position is compared, and feedback control is performed so as to move the stage so that the image sensor 15 returns to the position where it should be.
[0056]
  The drive circuit 104 receives a signal from the microcomputer 102 and receives an actuator.59,44A drive pulse having a frequency about 70% of the resonance frequency is output. The driving pulse is generated by the piezoelectric element 57,58And the first and second stages according to the following principle:12, 13Is moved along the vibration transmitting rods 28 and 47.
[0057]
  As shown in FIG. 9 (a), a sawtooth drive pulse having a gradual rise 110 and a sudden fall portion 112 is applied to the piezoelectric element 57,58As shown in (b2), the piezoelectric element 57,58Is gradually extended and displaced in the thickness direction, and the vibration transmitting rods 28 and 47 fixed to the piezoelectric element are gradually displaced in the axial direction. At this time, the stages 12 and 13 frictionally coupled to the vibration transmission rods 28 and 47 move together with the vibration transmission rods 28 and 47 by the frictional force.
[0058]
  On the other hand, at the sharp falling portion 112 of the drive pulse, the piezoelectric element 57,58Is rapidly contracted and displaced in the thickness direction, and the piezoelectric element 57,58The vibration transmission rods 28 and 47 coupled to the shaft are also rapidly displaced in the axial direction. At this time, as shown in (b3), the stages 12 and 13 frictionally coupled to the vibration transmission rods 28 and 47 overcome the frictional coupling force by the inertial force and substantially remain at that position and do not move. As a result, the stage moves to the right side from the initial state shown in (b1). Piezoelectric element 57,58By continuously applying the sawtooth drive pulse to the stage 12, the stages 12 and 13 can be continuously moved in the axial direction. Here, the phrase “substantially stays in that position and does not move” means that the vibration transmission rods 28 and 47 are moved between the stages 12 and 13 and the vibration transmission rods 28 and 47 in both the positive and negative directions. Stage with slip12, 13However, since the movement amount is not symmetrical, the stages 12 and 13 are moved in any desired direction.ButIncludes moving case.
[0059]
  In order to move the stages 12, 13 to the left, the piezoelectric elements 57,58If a drive pulse consisting of a rapid rise and a gentle fall is applied by changing the waveform of the sawtooth wave applied to, this can be achieved by the reverse action to that described above. Note that a rectangular wave or other waveforms can be applied to the drive pulse.
[0060]
  Base member11The first actuator held by the59When a drive pulse is applied to the piezoelectric element 57, the piezoelectric element 57 repeats expansion and contraction as described above. Expansion and contraction of the piezoelectric element 57 is transmitted to the weight 30 and the vibration transmission rod 28. The weight 30 hardly moves due to the difference in inertia mass between the weight 30 and the vibration transmission rod 28, and the expansion / contraction is transmitted only to the vibration transmission rod 28. The vibration transmitting rod 28 is bonded to the rod support arm 29 as described above, but the expansion and contraction is not hindered because the adhesive is elastically bent. As mentioned above,Vibration transmissionrod28The first stage 13 that frictionally couples at a speed difference that moves to the left and right moves in the X-axis direction along the vibration transmission rod 28. The first actuator 59 is subjected to a force to move within the fitting play due to the acceleration / deceleration of the first stage 13, but since the vibration transmission rod 28 and the rod support arm 29 are bonded, the movement does not occur. In addition to the correction performance, it is possible to prevent optical performance deterioration due to focus movement.
[0061]
  When the first stage 13 moves in the X-axis direction, the first stage13The second stage 12 connected to is also moved in the X-axis direction at the same time. The second stage 12 moves with little resistance and without shaking in the optical axis direction by the pressing spring 55 applied between the first stage 13 and the base member 11 and the rigid sphere 43 between the second stage 12 and the base member 11. To do. At this time, the flexible substrate 67 that connects the first and second substrates 17 and 18 changes the bent opening angle to absorb the movement of the first stage 13.
[0062]
  On the other hand, when a drive pulse is applied to the piezoelectric element 58 of the second actuator 44 held on the second stage 12, the piezoelectric element 58 repeats expansion and contraction as described above. Expansion and contraction of the piezoelectric element 58 is transmitted to the weight 46 and the vibration transmission rod 47. The weight 46 hardly moves due to the difference in inertia mass between the weight 46 and the vibration transmission rod 47, and the expansion / contraction is transmitted only to the vibration transmission rod 47. The vibration transmission rod 47 is bonded to the rod support arm 45 of the second stage 12 as described above, but the expansion and contraction is not hindered because the adhesive is elastically bent. As described above, the second stage 12 moves (self-runs) in the extending direction (Y-axis direction) of the vibration transmission rod 47 with respect to the first stage 13 due to the speed difference that moves to the left and right of the rod. The second actuator 44 is subjected to a force to move within the fitting play due to the acceleration / deceleration of the second stage 12, but cannot move because the vibration transmission rod 47 and the rod support arm 45 are bonded. Therefore, it is possible to prevent not only the correction performance but also optical performance deterioration due to focus movement.
[0063]
  Thus, when the drive pulse is applied to the second actuator 44, only the second stage 12 moves (self-runs) in the Y-axis direction independently of the first stage 13. The second stage 12 includes a pressing spring 55 applied between the first stage 13 and the base member 11, and the second stage 12 and the first stage.13Due to the hard sphere 43 between them, the resistance is small, and it moves without causing rattling in the optical axis direction. At this time, the flexible substrate 67 connecting the first and second substrates 17 and 18 is bent at the bent portion, so that the second stage12To absorb the movement of.
[0064]
  The first and second actuators 59 and 44 are coated with grease having adhesive properties on contact portions between the vibration transmission rods 28 and 47 and the two rod contact portions 53 and 54 of the first stage 13. By applying grease to the contact part, the rod contact part53, 54It is possible to prevent the polishing powder generated when the vibration transmission rod 28 and the vibration transmission rod 28 are repeatedly polished during use from being scattered due to the adhesive property of grease and adhering to the imaging surface of the imaging element 15 as dust.
[0065]
  As described above, according to the imaging apparatus according to the present embodiment, PSD62X, 62YHoldPSDholder14And the second substrate 18,Image sensor15And since it can be used as a sealing means of the drive mechanism, the apparatus can be miniaturized. Also optical unitAAnd imaging unitBThe gap is sealed by the sealing material provided between the two and the optical path opening can be sealed. Therefore, the imaging unitBThe optical axis can be adjusted and dust can be prevented from entering through the gap between the two.
[0066]
  Next, a second embodiment of the imaging device of the present invention will be described. FIG. 10 is an exploded perspective view of the image pickup apparatus according to the second embodiment of the present invention. The imaging apparatus according to the present embodiment has a structure that is generally the same as that of the imaging apparatus according to the first embodiment, and will be described focusing on different components.
[0067]
  According to this embodimentThe imaging device includes two units, an optical unit and an imaging unit. The lens barrel 3 of the present embodiment is composed of a main body that houses the taking lens and a bottom surface 3a having a larger diameter than the main body. The two units are fixed by adjusting their positions (turning and lens back). The fixing unit 20 provided in the optical unit is not the periphery of the lens barrel 3 but the bottom surface of the lens barrel 3.3aIt is formed in a protruding shape on the top. Fixing portions 20 and springs 21 provided at three locations adjust the distance between the optical unit and the imaging unit. Also, the entire imaging unit can be3aIn addition, a cap fixing hole 25a for fixing the dustproof cap 19 sealed from the outside is a bottom surface of the optical unit.3aIs provided.
[0068]
  Image sensor15The base member 11, the first stage 13, the second stage 12, and the PSD holder 14a that support and swing the lens are positioned around the imaging element 15 (including the first substrate 17), and the outer surface of the bottom surface 3a of the lens barrel 3 and the imaging element It arrange | positions so that the extra space of 15 outlines may be filled.
[0069]
  Base member11Large for the optical axis in the centerHoleIt is a metal frame having. Frame of base member 11ToThe PSD holder 14aFixing PSD holder for fixinghole,Fixing the lens barrel for fixing the base member 11 to the lens barrel 3HoleIs provided. Base member11A rod support arm extending in the Z-axis direction is erected, and the tip and end of the vibration transmission rod of the first actuator 59 are fixed to the two rod support arms by shaft fitting.
[0070]
  First stage 13 and second stage12Has the same structure as the imaging apparatus according to the first embodiment. That is, the first stage 13 moves in the X axis direction with respect to the base member 11, and the second stage 12 moves in the Y axis direction with respect to the first stage 13. Therefore, as a result, the second stage12The imaging element 15 fixed to the base member is a base member11Can move on the XY plane.
[0071]
  The PSD holder 14a is configured by walls extending in the X-axis and Y-axis directions, and is mounted with first and second PSDs 62X and 62Y that detect the amount of movement of the second stage 12. PSD holder14aAre fixed to the base member 11 so that the PSDs 62X and 62Y to be held can receive light from the LEDs provided on the first substrate 17.
[0072]
  The second substrate (not shown) is outside the dust cap 19 and the first substrate17And a flexible substrate 67.
[0073]
  The dustproof cap 19 is composed of a peripheral wall 19a and a bottom wall 19b, and is a cylindrical body with one side closed. The dust-proof cap 19 includes a screw retaining hole 73a provided in the lower portion of the peripheral wall 19a and a lens barrel.3The lens barrel so as to contain the above-described imaging device 15 and its driving mechanism by the cap fixing hole 25a of the bottom surface 3a of the lens3Bottom of3aIt is fixed to. Dust cap19There is a small opening 74 for allowing the flexible substrate 67 to pass through the upper surface 19b of the first substrate.17Flexible substrate connected to67Dustproof cap19It is possible to connect to the second substrate existing outside. In order to further improve the sealing performance of the small opening 74, the small opening74A sealing member (not shown) for sealing is provided, specifically, a flexible substrate.67The small opening 74 is closed with a tape or the like in a state where is folded.
[0074]
  As described above, according to the imaging apparatus according to the present embodiment, the dust-proof cap 19 is attached so as to cover the imaging element 15 and the entire drive mechanism thereof, so that the lens barrel bottom surface 3a and the dust-proof cap 19 are completely used. Sealed. Therefore, the image sensor15This prevents dust from adhering to the surface and reduces the problem of dust reflection. Further, the optical axis of the imaging unit can be adjusted by the protruding fixing portion 20 on the lens barrel bottom surface 3a, and a dustproof cap19As a result, the optical path opening is sealed, and the problem of dust reflection can be solved.
[0075]
  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a digital camera using an imaging apparatus of the present invention.
FIG. 2 is an exploded perspective view of the imaging apparatus according to the first embodiment of the present invention.
3 is a cross-sectional view of the image pickup apparatus of FIG. 2 cut along a II cross section.
4 is a cross-sectional view of the imaging apparatus of FIG. 2 cut along a II-II cross section.
5 is a cross-sectional view of the image pickup apparatus of FIG. 2 cut along a III-III cross section.
FIG. 6 is a diagram illustrating an arrangement configuration of photographing lenses used in the optical unit.
FIG. 7 is a schematic view showing a grounding structure of a heat sink using a flexible substrate.
8 is a block diagram showing an electrical structure of a drive control circuit of the camera shake correction imaging apparatus of FIG. 2;
FIG. 9 is a diagram for explaining a driving principle of an actuator. (A) is an example of the waveform of the drive pulse applied to a piezoelectric element. (B) is a figure explaining the movement of an actuator.
FIG. 10 is an exploded perspective view of an imaging apparatus according to a second embodiment of the present invention.
[Explanation of symbols]
  A Optical unit
  B Imaging unit
  1 Digital camera
  2 Camera body
  3Tube
  4 Lens
10 Imaging device
11 Base member
12 Second stage
13 First stage
14 PSD holder
15 Image sensor
16 Heat sink
17 First substrate
18 Second substrate
19 Dust-proof cap
20 Fixed part
21 Adjustment spring
22 Sealing material
23 frames
24 large hole (light path opening)
25 PSD holder fixing hole
44 Second actuator
59 First actuator
62X, 62Y PSD
67 Flexible substrate
86 Shooting unit side opening

Claims (5)

An optical unit comprising one or a plurality of photographing lenses and a lens barrel for housing the photographing lenses, an imaging unit for imaging subject light, and a movement for moving the imaging unit in an arbitrary direction on a plane perpendicular to the subject light An imaging unit having a camera shake correction function including a unit and a position detection unit that detects a position of the imaging unit, and the optical unit and the imaging unit are coupled so that the optical axis can be adjusted,
Before SL imaging unit is provided in the storage means in order to further comprising, transmitting the pre-Symbol subject light into the imaging means accommodating means for the inner hull movably between said imaging means and said moving means and said position detecting means was said housing means is connected to the optical unit the optical path aperture to seal optically, and the imaging means and the moving means and the position detection means is sealed imaging apparatus according to claim Rukoto.   The imaging apparatus according to claim 1, wherein the position detection unit includes a photodetector, and the storage unit is formed of a light non-transmissive member.   The imaging apparatus according to claim 1, wherein the optical unit includes a photographing lens that is always fixed so as to cover an imaging unit side opening of the lens barrel.   A ring-shaped elastic member having a larger dimension than the opening for the optical path and the opening on the imaging unit side of the lens barrel is used, and the opening for the optical path and the opening on the imaging unit side of the lens barrel are formed in the lumen of the elastic member. 4. The image pickup apparatus according to claim 1, wherein the optical path opening is hermetically sealed by sandwiching the elastic member between the optical unit and the image pickup unit.   5. The imaging apparatus according to claim 1, wherein at least a part of the storage unit is configured by a substrate for processing a signal output from the imaging unit. 6.

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