JP4317508B2 - Camera module and portable terminal equipped with the camera module - Google Patents

Description

  The present invention relates to a camera module and a mobile terminal including the camera module, and more particularly to a camera module configured to be small and light and a mobile terminal including the camera module.

  Camera modules used in mobile terminals such as recent cellular phones are equipped with high-speed, high-precision autofocus (AF) functions similar to those of ordinary electronic cameras (digital cameras) as the image sensor (CCD) increases in pixel count. And a focal length change (zoom) function are required, and further downsizing and weight reduction of the mobile terminal itself inevitably requires the camera module to be reduced in size and weight.

  In order to perform autofocus and change in focal length (zoom) in such a camera module, it is necessary to move the lens group in the direction of the optical axis. As shown in the figure, one cylindrical cam arranged on the side surface of the optical system is driven by a motor to drive the zoom lens frame and the AF lens frame, and the cylindrical cam is also arranged adjacent to the lens frame. Is driven by a motor, thereby moving the lens frame for autofocus and the zoom lens frame to switch between two points of tele and macro.

  In addition to the cylindrical cam, the autofocus lens frame and zoom lens frame are configured to be driven by the corresponding autofocus lead screw and zoom lead screw, and the lens closest to the subject is fixed to the front of the case. The lead screw is provided at the corner of one side of the case, the lens frame guide support portion is provided in the case, the zoom lead screw is provided in the first quadrant around the optical axis, and the focus lead screw is provided in the second quadrant. There is a camera module configured such that the guide shaft of the lens frame is arranged in the third quadrant, a camera module having a mechanism for moving the lens group in the optical axis direction using a helicoid mechanism, and the like.

  However, in conventional camera modules using such cylindrical cams, lead screws, helicoids, etc., electromagnetic motors or pulse motors having a rotor are generally used as the drive source. The electromagnetic motor that uses the rotor requires an electromagnet or permanent magnet around it, and even if the axial length is shortened, the cylindrical part is indispensable. In addition, noise is also generated.

  Therefore, in order to solve the disadvantages of such an electromagnetic motor, a piezo element (PZT) that generates mechanical distortion in response to changes in electric and magnetic fields has been conventionally used as a drive source for moving the lens frame in the optical axis direction. A frictional drive type drive source is used in which a mechanical vibrator is constituted by a piezoelectric element such as a rotor, and a rotor or a slider is brought into contact with the mechanical vibrator so that the vibration of the mechanical vibrator can be extracted as an output. Such a friction drive type drive source is low speed but has high torque and excellent response and controllability, enables fine positioning, has a holding torque (or holding force) when not energized, has excellent quietness, It has advantages such as small size and light weight.

  For example, Patent Document 2 and Patent Document 3 show a lens moving device in which a piezoelectric element is disposed in contact with an end of a feed screw for driving a lens frame to give an incremental rotation. The lens frame is moved by a feed screw that is rotated by the vibration of the conversion element in contact with the electro-mechanical energy conversion element that vibrates by applying an electric signal, as shown in Patent Document 5, A linear drive type vibration wave actuator (piezoelectric element) that directly drives the lens frame by abutting the piezoelectric element has been proposed.

  Furthermore, a piezoelectric element is disposed on either the lens frame or the lens barrel so that the lens is driven by the elliptical motion of the piezoelectric element, or a rotor is disposed at the end of the lead screw so as to contact the outer peripheral surface of the rotor. A structure in which a piezoelectric element is arranged and a rotor is rotated to move a lens has been proposed. As a friction drive type drive source using such a piezo element (PZT), for example, Patent Literature 6 to Patent Document 11 and the like.

JP 7-63970 A Japanese Patent Laid-Open No. 4-291213 JP-A-4-221910 JP-A-8-47273 JP-A-7-104166 JP-A-7-184382 Japanese Patent No. 2980541 JP 9-37575 A JP 2000-40313 A Special table 2002-529037 gazette Japanese Patent Laid-Open No. 2003-501988

  However, the techniques disclosed in Patent Documents 2 to 5 are mechanisms for driving a camera lens of a normal size, and camera modules used in mobile terminals such as mobile phones are always required to be downsized. It's too big to be applied to these mobile devices.

  Therefore, an object of the present invention is to provide a camera module that can be configured to be small and lightweight even when an autofocus (AF) function and a zoom function are incorporated, and a portable terminal including the camera module.

In order to solve the above problems, the camera module according to the present invention is:
A first lens holding portion that holds at least one optical lens and is movable in the optical axis direction;
A first shaft member and a second shaft member disposed substantially symmetrically and in parallel with respect to the optical axis;
A first piezo element disposed on the first lens holding portion and having a first operating portion that contacts the first shaft member at an end;
A second piezo having a second actuating portion in contact with the second shaft member at the end and disposed substantially symmetrically about the optical axis with respect to the first piezo element in the first lens holding portion. Elements,
It is characterized by including.

  As described above, the first and second piezo elements are arranged in the first lens holding section that holds the optical lens and is movable in the optical axis direction, and the operation section of each piezo element is centered on the optical axis. When the respective piezoelectric elements are driven by contacting the first and second shaft members disposed substantially symmetrically and in parallel with each other, the first lens holding portion that holds these piezoelectric elements moves up and down, and zooming is performed. Therefore, a camera module incorporating an autofocus (AF) function or a zoom function can be made small and lightweight.

  The second lens holding unit that holds at least one optical lens and is movable in the optical axis direction, and the first lens holding unit is movably guided and arranged in parallel with the optical axis. A guide shaft member, and a second guide shaft member that guides the first lens holding portion so as to be movable, and is disposed substantially symmetrically about the optical axis with respect to the first guide shaft. In a preferred embodiment of the present invention, the second lens holding portion is movably guided by the first shaft member and the second shaft member.

  The first piezo element and the second piezo element have a substantially rectangular plate-shaped outer shape, are substantially perpendicular to the optical axis, and are held in the first lens holding unit. By disposing at the outer peripheral position, the camera module can be made smaller.

  Further, the first lens holding unit is configured to hold a lens holding unit body that holds an optical lens, a first element holding unit that holds the first piezo element, and a second element that holds the second piezo element. The slit is divided into three parts of a two-element holding portion, and the slit is formed substantially symmetrically about the optical axis, and the first lens holding portion is formed by the slit by the first piezo. In a preferred embodiment of the present invention, the first operating portion of the element is biased to the first shaft member, and the second operating portion of the second piezo element is biased to the second shaft member. In this way, by providing the slit in the first lens holding portion, it is possible to give freedom in the circumferential direction of the held lens and rigidity in the optical axis direction. Contact with the second shaft member with a suitable contact pressure Since it is, the first lens holding portion can lower the first and second shaft members smoothly.

  The lens holding portion main body of the first lens holding portion includes a first roller member that contacts the first guide shaft member and a second roller member that contacts the second guide shaft member as an optical axis. The first lens holding portion can move the first and second shaft members up and down more smoothly by arranging them symmetrically about the center.

A first locked portion provided on the subject side of the second lens holding portion; a second locked portion provided on the imaging side of the second lens holding portion; A locked portion that can be selectively locked with the locked portion or the second locked portion.
The camera module further includes an unlocking part provided in the first lens holding part, and the unlocking part moves the first lens holding part in accordance with the movement of the first lens holding part. Selectively unlocking the locked portion or the second locked portion to the locking portion,
An engaged portion provided in the second lens holding portion; and an engaging portion engageable with the engaged portion of the second lens holding portion provided in the first lens holding portion. When the first locked portion of the second lens holding portion is locked to the locking portion, the unlocking portion is moved by the movement of the first lens holding portion toward the subject side. The locking between the first locked portion and the locking portion is released, and the engaging portion of the first lens holding portion and the engaged portion of the second lens holding portion are engaged. As a result, the first lens holding portion and the second lens holding portion are integrally moved to the subject side, and the second locked portion of the second lens holding portion and the locking portion are locked. By configuring to be
Since the second lens holding portion is locked by the first locking portion and the second locking portion as the first lens holding portion moves, the lens held by the second lens holding portion is focused. By using the lens for changing the distance and the lens held by the first lens holding portion as the focusing lens, a camera module having two focal lengths can be configured with a simple mechanism.

  Further, a third lens that holds at least one or more optical lenses and positions and fixes the first shaft member, the second shaft member, the first guide shaft member, and the second guide shaft member together. Since the holding portion is further included and the locking portion is arranged in the third lens holding portion, the first and second shaft members, the first and second guide shaft members are firmly fixed, and the first and second shaft members are more smoothly fixed. The first lens holding member and the second lens holding member can be moved up and down.

And in order to solve the said subject, the portable terminal in this invention is
A first lens holding portion that holds at least one optical lens and is movable in the optical axis direction;
A first shaft member and a second shaft member arranged substantially symmetrically and in parallel with respect to the optical axis;
A first piezo element disposed on the first lens holding portion, and having an operating portion in contact with the first shaft member at an end;
A second piezo element having an operation part in contact with the second shaft member at an end, and disposed substantially symmetrically about the optical axis with respect to the first piezo element in the first lens holding part;
A camera module including
An operation member, a display member, a battery, a communication unit, the camera module, the operation member, the display member, the battery, and a housing that houses the communication unit,
In a preferred embodiment, the thickness dimension of the housing is substantially restricted to the height of the camera module.

  According to the present invention, it is possible to provide a small and lightweight camera module that incorporates an autofocus (AF) function and a zoom function, and a portable terminal including the camera module.

  Hereinafter, exemplary embodiments will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.

  1A and 1B are perspective views of the camera module of the embodiment, in which FIG. 1A shows a state where the focal length changing lens is on the telephoto (tele) side, and FIG. 1B shows the focal length changing lens on the wide angle side. It shows a certain state. FIG. 2 shows a third lens unit holding the third lens group by removing the third lens holding unit holding the first lens group on the subject side and the second lens holding unit holding the second lens group in FIG. FIG. 3 is a perspective view showing one lens holding portion, a shaft member and a guide shaft member for moving the first lens holding portion up and down, and a part of a mechanism for moving the second lens holding portion. FIG. FIG. 4 is a plan view of the holding portion, FIG. 4A is a view of the holding portion of the piezoelectric element in the first lens holding portion as viewed from the outside of the camera module, FIG. 4B is a view as viewed from the lens side, and FIG. FIG. 6 is a perspective view showing a mechanism for moving and fixing a lens group that changes the focal length in the camera module of the embodiment, and FIG. 6 is a mechanism for changing the focal length in the camera module of the embodiment and a lens moving state during autofocusing. Explain FIGS. 7A and 7B show a state in which the lens constituting the optical system in the camera module of the embodiment is on the wide angle (wide) side (A), a state on the telephoto (tele) side (B), and a telephoto (tele) side. FIG. 8C is a view for explaining the movement range of the focusing lens on the wide angle side, FIG. 8 is a perspective view of the piezo element used in the camera module according to the embodiment, and the operation principle. FIGS. 9B and 9C are plan views of modified examples of the first lens holding portion, and FIG. 10 is a cross-sectional view showing another embodiment for moving the focal length changing lens holding portion. FIG. 11 is a diagram schematically illustrating an example of a mobile phone in which the camera module of the embodiment is incorporated. In the figure, the same number is attached | subjected to the same component.

  1A and 1B are perspective views of the camera module 1 according to the embodiment, in which FIG. 1A shows a state where the focal length changing lens is on the telephoto (tele) side, and FIG. FIG. 2 illustrates a third lens holding unit 20 that holds the first lens group 2 on the subject side in FIG. 1 and a second lens holding unit 21 that holds the second lens group 3. The first lens holding portion 22 holding the third lens group 4, the shaft member 23 for moving the first lens holding portion 22 up and down, the guide shaft member 24, and the second lens holding portion 21 are moved. It is the perspective view which showed a part of mechanism made to do. The camera module 1 in this embodiment is described as a bifocal type camera module that switches the focal length between a telephoto (tele) side and a wide angle (wide) side as an example. However, the present invention is not limited to the bifocal type, and is continuous. The present invention is also applicable to a normal zoom lens that can change the focal length.

  As shown in FIG. 7 and described later, the camera module 1 of the embodiment shown in FIG. 1 includes a first lens group 2 on the subject side, a second lens group 3 disposed on the imaging element 5 side, Further, as shown in FIG. 2, it has a third lens group 4 (not shown in FIG. 1) arranged on the image sensor 5 side, and each lens group holds the first lens group 2. A third lens holding unit 20, a cylindrical second lens holding unit 21 that holds the second lens group 3, and a first lens holding that holds a third lens group 4, which will be described in detail later with reference to FIGS. Held in the portion 22.

  Then, support arms 211 provided in the second lens holding portion 21 are inserted into substantially corner portions of the third lens holding portion 20 and a base 26 that holds the imaging element 5 such as a CCD (not shown). The operation portion of the piezo element 10, which has a substantially rectangular plate-like outer shape, is disposed in the first lens holding portion 22 in a direction substantially perpendicular to the optical axis, and will be described in detail with reference to FIG. 8. In order to move the second lens holding portion 21 and the first lens holding portion 22 up and down by bringing a certain spacer 15 into contact therewith, a shaft member 23 arranged substantially symmetrically and in parallel with respect to the optical axis, and a guide shaft A member 24 is provided.

  Further, from the third lens holding unit 20, the second lens group 3 held by the second lens holding unit 21 is fixed to the wide-angle side and the telephoto side, and as shown in FIG. The latch arm 25 is suspended, and grooves 212 and 213 as latched portions for latching the latch arm 25 are provided above and below the outer periphery of the second lens holding portion 21. Further, when the second lens holding portion 21 is moved up and down for changing the focal length, the first lens holding portion 22 is provided with a convex portion on the outer peripheral side as shown in FIG. A second lens holding part moving member 226 having an engaging part for moving the second lens holding part 21 together with an unlocking part for releasing the latch of the latch arm 25 with respect to the part 21, and the first lens holding part 22 The V-shaped roller 225, which is a roller member, is provided at two locations on the right side of the first lens holding portion 22 in the upper and lower sides and only one on the left side for balance. The details of the mechanism for moving the second lens holding portion 21 for changing the focal length will be described later in detail with reference to FIGS.

  FIG. 7 shows a state (A) where the lens constituting the optical system in the camera module of the embodiment is on the wide-angle (wide) side, a state (B) where the lens is on the telephoto (tele) side, and a telephoto (tele) side and wide-angle ( FIG. 8C is a diagram (C) for explaining the moving range of the focusing lens on the wide side, and is for changing the focal length arranged on the first lens group 2 on the subject side and on the imaging element 5 side. FIGS. 7A and 7B show the second lens group 3 and the third lens group 4 for changing the focal length disposed on the image sensor 5 side and for focusing (focusing). As shown in FIG. 7A, the second lens group 3 and the third lens group are each composed of at least one optical lens and the first lens group 2 is fixed in position. Telephoto (telephoto) when 4 moves to the image sensor 5 side using a CCD or the like Becomes, the second lens group 3 as shown in FIG. 7 (B), the a wide-angle when the third lens group 4 is closer to the first 2-side lens unit.

  Then, as shown in FIG. 7C, the position of each lens group and the moving range for focusing are shown in correspondence with the lens group positions shown in FIGS. 7A and 7B. For the purpose of focusing, the third lens group 4 has, for example, the range indicated by 6 in FIG. 7C in the case of the wide-angle (wide) side in FIG. In the case of the tele side, the range shown by 7 in FIG. 7C is moved to focus (focus).

  The camera module 1 of the embodiment shown in FIG. 1 realizes this movement of the accommodated lens group by using the piezo element 10 as shown in FIG. 8, and FIG. FIG. 4 is a perspective view of a piezo element used in a camera module according to the embodiment, (B) is a configuration of the piezo element, and (C) is a diagram for explaining an operation principle. As described in detail in Patent Documents 6 to 11, the piezo element 10 used here is the length of a piezoelectric ceramic (piezo element) 11 formed in a substantially rectangular plate-like outer shape in FIG. As shown in FIG. 8 (B), four electrodes 121, 122, 123, and 124 are formed on the entire surface of the second surface 13 on the opposite side. One electrode is provided. The electrodes 121, 122, 123, and 124 on the first surface 12 are formed by the wires 125 and 126 that are arranged in the vicinity of the connecting portions of the respective electrodes 121, 122, and 123, 124 arranged in the diagonal direction. It is preferable that the electrodes are electrically connected and the second surface 13 is grounded.

  Further, on the third surface 14 in the short direction, a spacer 15 which is a relatively hard ceramic operating portion is attached by, for example, a bonding agent, preferably near the center of the side, to the object 16 to be relatively moved. It is designed to engage. Further, as shown in FIG. 8B, the piezoelectric ceramic (piezo element) 11 can be deformed by a pair of support bodies 171 and 172 fixed around and a support body 173, 174 and 175 with springs. Supported by

  When a positive voltage is applied to the electrodes 121 and 124 and a negative voltage is applied to the electrodes 122 and 123 in the piezoelectric ceramic (piezo element) 11 configured as described above, the piezoelectric ceramic (piezo element) 11 is shown in FIG. ), The left side of the figure is longer than the right side and can be deformed by being supported by spring-supported supports 173, 174, 175, so that the object with which the spacer 15 is engaged is shown. Move 16 right. When no voltage is applied, the piezoelectric ceramic (piezo element) 11 returns to its original state. At this time, for example, when an asymmetric voltage pulse whose fall time is at least four times longer than the rise time is applied to the electrode, the piezoelectric ceramic. Due to the friction between the spacer 15 and the object 16 in the (piezo element) 11, the spacer 15 returns to the starting position while the spacer 15 and the object 16 are engaged at the fall of the pulse. And the object 16 move relatively. When the voltage is applied in the reverse direction, the piezoelectric ceramic (piezo element) 11 is deformed in the opposite direction, and thus the spacer 15 and the object 16 move in the opposite directions.

  In this way, the piezoelectric ceramic (piezo element) 11 continuously gives a signal voltage that causes deformation as shown in FIG. 8C, so that the object 16 is caused by friction between the spacer 15 and the object 16. Since the relative position is displaced, it is low-speed but high torque, excellent response and controllability, fine positioning is possible, and it has a holding torque (or holding force) when there is no power, quietness It is a drive source having advantages such as being excellent in size, small size and light weight.

  3 is a plan view of the first lens holding portion 22 holding the third lens group 4, and FIG. 4 is a view of the holding portion of the piezo element in the first lens holding portion as viewed from the outside of the camera module. (A) and the figure (B) seen from the lens side. The first lens holding unit 22 holding the third lens group 4 moves the second lens holding unit 21 holding the second lens group 3 up and down, as shown in FIG. As shown in the plan view of FIG. 3, two second lens holding portion moving members 226 having an unlocking portion and an engaging portion constituting the latch mechanism shown are provided symmetrically with respect to the optical axis. The third lens group 4 described above is held at the center. The first lens holding portion 22 is opposed to the central portion 221 provided with the third lens group 4 via a slit 223 formed substantially symmetrically about the optical axis, and is connected by a thin portion 224. A holding portion 222 of the piezo element 10 that is substantially perpendicular to the optical axis is provided and divided into three parts. Further, a rotationally symmetric position with respect to the central optical axis of the lens group 4 is shown in FIG. As described above, V-shaped rollers 225 that are roller members that move the first lens holding portion 22 up and down while preventing rotation are disposed at two locations in the upper and lower portions, respectively. As described above, the holding portion 22 of the piezo element 10 on the opposite side across the optical axis has only one V-type roller 225 for balancing.

  The holding part 222 of the piezo element 10 in the first lens holding part 22 is provided with a holding part 228 for holding the main part of the piezo element 10 by opening the left side in the drawing as shown in FIG. 8B is provided so that a space for inserting and holding the piezo element 10 is provided in the piezo element 10 and the piezo element 10 can be deformed as shown in FIG. 8C. In addition, a member corresponding to the support shown by 171 and 172 and the support with spring shown by 173 and 174 (coil spring 227 corresponds to the support with spring of 175) is provided.

  Further, as shown in FIG. 4B, on the right side of the holding portion 228 in the drawing, as described above, the guide shaft member 24 has V in two places on the upper and lower sides so that the holding portion 228 can be smoothly moved up and down. A V-shaped roller 225 is provided as a roller member with which the mold portion abuts.

  On the other hand, between the holding portion 222 of the piezo element 10 and the central portion 221 where the second lens group 3 is arranged, the spacer 15 in the piezo element 10 arranged in the holding portion 222 is pressed against the shaft member 23 with a predetermined pressing force. Therefore, the coil spring 227 is disposed at a position corresponding to the position where the V-shaped roller 225 is provided, and the holding portion 222 of the piezo element 10 and the central portion 221 where the second lens group 3 is disposed are separated from each other. The power of is added.

  The coil spring 227 has, for example, a hole for receiving the coil spring 227 on the central portion 221 side where the third lens group 4 is arranged, and this holding portion on the holding portion 222 side of the piezo element 10 opposed through the slit 223. A hole with an internal thread cut through the outer wall of 222 is provided, and a coil spring 227 is inserted into the hole on the central portion 221 side through this hole, and then the male screw is inserted to close the hole and adjust the pressure contact force of the coil spring 227 The central portion 221 provided with the third lens group 4 and the holding portion 222 side of the piezo element 10 are separately created, and a hole for inserting the coil spring 227 is provided in both, and the coil spring 227 is inserted. Thereafter, the thin portions 224 are provided so as to be connected to each other by screwing, welding, or the like. Further, the thin portion 224 is formed of a spring member, and the holding portion 222 of the piezo element 10 is opened from the central portion 221 where the second lens group 3 is arranged by utilizing the spring property, and the coil spring 227 is formed in a hole provided in these portions. May be loaded.

  By providing the slit 223 and the coil spring 227 in the first lens holding portion 22 in this way, the third lens group 4 held by the slit 223 has a degree of freedom in the circumferential direction and rigidity in the optical axis direction. Furthermore, the spacer 15 in the piezo element 10 disposed on the holding portion 222 by the coil spring 227 can be pressed against the shaft member 23 with a predetermined pressing force. Then, the first lens holding portion 22 to which a force that rotates around the optical axis is applied to the shaft member 23 by the pressing force is stopped by the V-type roller 225 in contact with the guide shaft member 24, By applying a signal voltage that continuously causes deformation as shown in FIG. 8C to the piezo element 10, the first lens holding portion 22 is caused by the frictional force between the spacer 15 and the shaft member 23. Can move up and down.

  On the other hand, as shown in FIG. 1, the second lens holding portion 21 that holds the second lens group 3 is supported by a support arm 211 that extends in the direction of the shaft member 23 and passes through the shaft member 23. As the lens holding portion 22 is moved up and down, it is latched by the latch mechanism shown in FIGS. 5 and 6 at positions on the telephoto (tele) side in FIG. 1A and the wide-angle (wide) side in FIG. .

  FIG. 5 schematically shows components constituting the latch mechanism. FIG. 6 shows that the second lens holding portion 21 that holds the second lens group 3 by the latch mechanism schematically shown in FIG. It is the schematic diagram which showed how it moved by the movement of the 1st lens holding | maintenance part 22 holding 3 lens groups 4, and how it was fixed. In the figure, reference numeral 21 denotes a part of the second lens holding portion 21 that holds the second lens group 3 indicated by 21 in FIG. 1 and is a locked portion provided above and below the second lens holding portion 21. Grooves 212 and 213 are latch grooves for latching by a latch portion 251 which is a latching portion provided on the latch arm indicated by 25 in FIG. 1, and 214 is a groove 226 in FIGS. 1, 2, and 3. Engagement for moving the second lens holding portion 21 holding the second lens group 3 downward in the figure by engaging the first engaging portion 226f of the second lens holding portion moving member shown. A portion bent in a mountain shape on the side of the lens holding portion 21 in the latch arm 25 indicated by a joint portion 251 is a latch portion which is a locking portion, and 252 is a latch of the latch portion 251 in the latch arm 25. Parts for releasing the latch 226b, 226c, Reference numeral 26d denotes an inclined portion (226b, 226d) and a top portion (226c), which are latch release portions for releasing the latch of the latch portion 251 on the latch release portion 252 on the latch arm 25, and 226a, 226e are As described above, the flat portion 226 f that is latched is the first engaging portion, and 226 g is the second engaging portion that engages with the engaged portion 214.

  6A shows a wide-angle state in which the second lens group 3 and the third lens group 4 shown in FIG. 7A are separated from the first lens group 2, and FIG. ) Is the telephoto state shown in FIG. 7B in which the second lens group 3 and the third lens group 4 are close to the first lens group 2, and FIGS. It is an intermediate state. Similarly, FIG. 6 (P) shows a wide-angle state in which the second lens group 3 and the third lens group 4 are separated from the first lens group 2, and FIG. 6 (K) to (N) in the meantime. Is an intermediate state. 6A shows the range in which the third lens group 4 on the wide-angle side shown by 6 in FIG. 7C moves for focusing. Reference numeral 7 in 6 (H) denotes a range in which the third lens group 4 on the telephoto side moves for focusing.

  In the wide-angle state where the second lens group 3 and the third lens group 4 in FIG. 6A are separated from the first lens group 2, as shown in FIG. The latch portion 251 of the latch arm 25 suspended from the portion 20 latches the latch groove 212 in the second lens holding portion 21 and fixes it at the wide-angle position, and the second lens provided in the first lens holding portion 22. Since the lens holding portion moving member 226 is provided with the engaged portion 214 in the second lens holding portion 21 between the first engaging portion 226f and the second engaging portion 226g, the first lens holding portion 226 is provided. Even if the portion 22 is driven by the piezo element 10 for focusing (focusing) and moves within the range indicated by reference numeral 6, it can move without contacting the engaged portion 214.

  When shifting from this state to the telephoto state shown in FIG. 7B, as shown in FIG. 6B, the first lens holding portion 22 is driven upward in the figure by the piezo element 10. The second lens holding portion moving member 226 is raised, and the inclined portion 226d pushes up the latch release portion 252 in the latch arm 25. Then, as shown in FIG. 6C, when the latch release portion 252 reaches the top portion 226c of the second lens holding portion moving member 226, the latch portion 251 of the latch groove 212 in the second lens holding portion 21 latches. 6D, the latch release portion 252 rides on the top portion 226c of the second lens holding portion moving member 226, and the latch portion 251 comes into contact with the second lens holding portion 21. At the same time, the engaged portion 214 and the second engaging portion 226g come into contact with each other, and the second lens holding portion 21 is pushed up.

  Then, as shown in FIGS. 6E, 6F, and 6G, when the second lens holding portion 21 is pushed up and reaches the state of FIG. 6H, the latch 25 in the latch arm 25 is now latched. The part 251 latches the latching groove 213 in the second lens holding part 21 and fixes it at the telephoto position. Therefore, as in the case of FIG. 6A, the second lens holding portion moving member 226 provided in the first lens holding portion 22 has a first engagement portion 226f and a second engagement portion 226g. Since the engaged portion 214 of the second lens holding portion 21 is provided therebetween, the first lens holding portion 22 is driven by the piezo element 10 for focusing (focusing), and is denoted by reference numeral 7. Even if the range is moved, it can move without contacting the engaged portion 214.

  To return to the state shown in FIG. 6A from this state, as shown in FIG. 6K, the first lens holding portion 22 is driven downward in the figure by the piezo element 10, The second lens holding portion moving member 226 descends, and the inclined portion 226b pushes up the latch release portion 252 in the latch arm 25. Then, as shown in FIG. 6L, when the latch release portion 252 reaches the top portion 226c of the second lens holding portion moving member 226, the latch portion 251 of the latch groove 213 in the second lens holding portion 21 is latched. 6 and further descends to the state shown in FIG. 6 (M), and when the latch release portion 252 rides on the top portion 226 c of the second lens holding portion moving member 226, the latch portion 251 contacts the second lens holding portion 21. At the same time, the engaged portion 214 and the first engaging portion 226f come into contact with each other, and the second lens holding portion 21 is pushed down.

  Then, when the second lens holding portion 21 is pushed down as shown in FIG. 6 (N) and the state shown in FIG. 6 (P) is reached, the latch portion 251 in the latch arm 25 is now latched in the second lens holding portion 21. The groove 212 is latched and fixed at the wide-angle position, and the state returns to the state shown in FIG.

  In the camera module 1 of the embodiment configured as described above, the spacer 15 vibrates and reciprocates as described above by applying a drive current consisting of a drive signal to the piezo element 10 by a control circuit (not shown). The first lens holding portion 22 that is excited and holds the piezo element 10 moves upward or downward in FIG. Therefore, for example, as shown in FIG. 1A, the second lens holding unit 21 is in the telephoto position (in FIG. 6H), and the camera module 1 is focused by a control circuit (not shown). In this case, by moving the first lens holding portion 22 within the range indicated by 7 in FIG. 7C, the focus on the image sensor indicated by 5 in FIG. 7B can be adjusted.

  When the camera module 1 is set to the wide-angle side shown in FIG. 1B (the state (P) or (A) in FIG. 6) from this state, the piezo element 10 is connected to the piezo element 10 by a control circuit (not shown). A drive current for moving the first lens holding unit 22 downward is applied. Then, the first lens holding portion 22 is lowered, and accordingly, the latch release portion 252 of the latch arm 25 shown in FIG. 5 rides on the inclined portion 226b of the second lens holding portion moving member 226, and the latch portion 251 is moved. The latch is disengaged from the latch groove 213 provided in the second lens holding portion 21.

  Then, when the first lens holding portion 22 is moved downward as it is, the latch portion 251 in the latch arm 25 is put on the latch groove 212 and the second lens holding portion 21 is fixed in the state shown in FIG. By moving the first lens holding unit 22 within a range indicated by 6 in FIG. 7C, the image sensor indicated by 5 in FIG. 7A can be focused. Accordingly, the movement range indicated by 6 and 7 in FIG. 7C in which the first lens holding portion 22 moves for focusing is the first engagement portion of the second lens holding portion moving member 226 in FIG. 226f and the second engaging portion 226g are within a range in which they can move without contacting the engaged portion 214. Note that the movement from the wide-angle side to the telephoto side is omitted because it has been described with reference to FIG.

  By configuring the camera module 1 in this way, it is possible to perform autofocus (AF) and change in focal length by simply applying a signal current to the piezo element 10, and the piezo element 10 is low in speed as described above. However, because it has advantages such as high torque, excellent response and controllability, small positioning and small size and light weight, it is a small and lightweight camera module that can change focal length and focus in a short time. Can be provided.

  Note that the configuration of the first lens holding portion 22 shown in FIG. 3 that holds the third lens group 4 and the configuration of the latch mechanism shown in FIG. 9, the latch 22 is not suspended from the third lens holding part 20 for holding the first lens group 2 as shown in FIG. As shown, it may be in the form of an arm 27 that rises from the base 26. In the first lens holding portion shown in FIG. 9, the same components as those used in the first lens holding portion 22 shown in FIG.

  First, the first lens holding portion shown in FIG. 9 makes the piezo element 10 contact the shaft member 23 in the first lens holding portion 22 shown in FIG. 3 and makes the V-shaped roller 225 contact the guide shaft member 24. The point to make is the same. However, in order to press the piezo element 10 against the shaft member 23, in the embodiment of FIG. 3, the central portion 221 where the third lens group 4 is arranged by the slit 223 and the holding portion 222 of the piezo element 10 are separated, and a coil spring is interposed therebetween. However, in the embodiment of FIG. 9, the urging member 19 is provided by bending the shaft holding member 18 of the V-shaped roller 225. By doing so, the coil spring Since it is not necessary to insert 227 between the central portion 221 where the third lens group 4 is disposed and the holding portion 222 of the piezo element 10, the assembly is facilitated accordingly. The operations and effects in this case are the same as those of the embodiment shown in FIG.

  Further, the latch mechanism shown in FIG. 10 does not hang the latch arm 25 shown in FIG. 1 from the third lens holding portion 20 holding the first lens group 2 but is an arm that rises from the base 26. 27, and the other operations are the same as those described with reference to FIGS. 5 and 6 and will not be described.

  FIG. 11 is an example of a portable terminal incorporating the camera module 1 described above. The mobile terminal shown in FIG. 11 shows a case of a mobile phone 50 as an example. In the figure, 51 is an operation unit (operation member), 52 is a display (display member), and FIG. 11 is a plan view showing the operation unit (operation member) 51 and the display (display member) 52 visible (open state). In the illustrated mobile phone 50, a first case portion 53 on which an operation portion 51 is mounted and a second case portion 54 on which a display 52 is mounted are connected by a hinge mechanism 55, and the first and first case portions are connected. The two case portions 53 and 54 are rotatable around the hinge mechanism 55. In addition, the 1st and 2nd case parts 53 and 54 comprise a case body.

  The second case 54 incorporates the above-described camera module 1 as shown by a broken double circle in the figure, and when a predetermined button of the operation unit 51 is operated, the camera module 1 takes an image, The captured image is displayed on the display 52, for example. Note that the upper side of the camera module 1 shown in FIG. 1 is directed to the outside of the second case portion 54. That is, the second case portion 54 is formed with an opening that exposes the first lens group 2 held by the third lens holding portion 20 in the camera module 1. A battery unit, a communication unit, and the like are accommodated in the case unit 53, and the thickness dimension of the second case unit 54 is substantially regulated by the height of the camera module 1.

  As described above, according to the present embodiment, it is possible to provide a small and lightweight camera module incorporating an autofocus (AF) function and a zoom function, and a portable terminal equipped with the camera module. .

  A camera module incorporating an autofocus (AF) function and a zoom function can be configured to be small and lightweight, and is optimal as a camera module in various small portable terminals.

1A and 1B are perspective views of a camera module according to an embodiment, in which FIG. 1A shows a state in which a focal length changing lens is on the telephoto (tele) side, and FIG. Show. The first lens holding section for holding the third lens group is removed by removing the third lens holding section for holding the first lens group on the subject side and the second lens holding section for holding the second lens group in FIG. FIG. 5 is a perspective view showing a part of a mechanism for moving a shaft member, a guide shaft member, and a second lens holding part for moving the first lens holding part up and down. It is a top view of the 3rd lens holding part. FIG. 5A is a view of the holding portion of the piezoelectric element in the third lens holding portion as viewed from the outside of the camera module, and FIG. 8B is a view as viewed from the lens side. It is the perspective view which showed the latch mechanism for the movement and fixation of the lens group which changes the focal distance in the camera module of embodiment. It is a figure for demonstrating the mechanism which changes the focal distance in the camera module of embodiment, and the lens movement state at the time of autofocus. In the camera module of the embodiment, the lens constituting the optical system is on the wide angle (wide) side (A) and on the telephoto (tele) side (B), and on the telephoto (tele) side and wide angle (wide) side It is a figure (C) for demonstrating the movement range of the lens for a focusing. FIG. 3 is a perspective view (A) of a piezo element used in the camera module according to the embodiment, a diagram (B) for explaining the configuration of the piezo element, and a figure (C) for explaining the operating principle. It is a top view of the modification in the 1st lens holding part. It is sectional drawing which showed the other Example which moves the lens holding | maintenance part for focal length changes. It is a figure which shows roughly an example of the mobile telephone with which the camera module of embodiment was incorporated.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera module 2 1st lens group 3 2nd lens group 4 3rd lens group 5 Image pick-up element 10 Piezo element 20 3rd lens holding | maintenance part 21 holding 1st lens group 2 2nd lens group 3 Holding second lens holding portion 211 Support arm 212, 213 Latching groove 22 First lens holding portion 225 holding third lens group 4 V-type roller 226 Second lens holding portion moving member 23 Shaft member 24 Guide shaft member 25 Arm 26 for latch 26 Base

Claims (12)

A first lens holding portion that holds at least one optical lens and is movable in the optical axis direction;
A first shaft member and a second shaft member disposed substantially symmetrically and in parallel with respect to the optical axis;
A first piezo element disposed on the first lens holding portion and having a first operating portion that contacts the first shaft member at an end;
A second piezo having a second actuating portion in contact with the second shaft member at the end and disposed substantially symmetrically about the optical axis with respect to the first piezo element in the first lens holding portion. Elements,
A camera module comprising: A second lens holding unit that holds at least one optical lens and is movable in the optical axis direction;
A first guide shaft member that movably guides the first lens holding portion and is disposed in parallel with the optical axis;
A second guide shaft member that guides the first lens holding portion so as to be movable, and is arranged substantially symmetrically about the optical axis with respect to the first guide shaft;
2. The camera module according to claim 1, wherein the second lens holding portion is movably guided by the first shaft member and the second shaft member.   The first piezo element and the second piezo element have a substantially rectangular plate-like outer shape, are in a direction substantially perpendicular to the optical axis, and are positioned at the outer periphery of the optical lens held by the first lens holding portion. The camera module according to claim 1, wherein the camera module is disposed in a position.   The first lens holding unit includes a lens holding unit main body that holds an optical lens, a first element holding unit that holds the first piezo element, and a second element that holds the second piezo element by a slit. 4. The camera module according to claim 1, wherein the camera module is divided into three portions of the holding portion.   The camera module according to claim 4, wherein the slits are formed substantially symmetrically about the optical axis.   The first lens holding portion biases the first operating portion of the first piezo element to the first shaft member by the slit, and the second operating portion of the second piezo element is the second. 6. The camera module according to claim 4, wherein the camera module is biased to the shaft member.   The lens holding portion main body of the first lens holding portion has a first roller member in contact with the first guide shaft member and a second roller member in contact with the second guide shaft member centered on the optical axis. 7. The camera module according to claim 4, wherein the camera module is arranged substantially symmetrically. A first locked portion provided on the subject side of the second lens holding portion;
A second locked portion provided on the imaging side of the second lens holding portion;
The camera according to claim 1, further comprising a locking portion that can be selectively locked with the first locked portion or the second locked portion. module. The camera module further includes an unlocking portion provided in the first lens holding portion,
With the movement of the first lens holding part, the locking release part locks the second lens holding part to the first locked part or the second locked part to the locking part. 9. The camera module according to claim 8, wherein the camera module is selectively canceled. An engaged portion provided in the second lens holding portion;
An engaging portion engageable with an engaged portion of the second lens holding portion provided in the first lens holding portion;
When the first locked portion of the second lens holding portion is locked to the locking portion, the locking releasing portion is moved to the subject side by the movement of the first lens holding portion toward the subject side. The engagement between the first locked portion and the locking portion is released, and the engaging portion of the first lens holding portion and the engaged portion of the second lens holding portion are engaged. The first lens holding part and the second lens holding part move integrally to the subject side, and the second locked part of the second lens holding part and the locking part are locked. The camera module according to claim 9. A third lens holding portion that holds at least one optical lens and positions and fixes the first shaft member, the second shaft member, the first guide shaft member, and the second guide shaft member together. Further including
The camera module according to claim 8, wherein the locking portion is disposed in the third lens holding portion. A first lens holding portion that holds at least one optical lens and is movable in the optical axis direction;
A first shaft member and a second shaft member arranged substantially symmetrically and in parallel with respect to the optical axis;
A first piezo element disposed on the first lens holding portion, and having an operating portion in contact with the first shaft member at an end;
A second piezo element having an operation part in contact with the second shaft member at an end, and disposed substantially symmetrically about the optical axis with respect to the first piezo element in the first lens holding part;
A camera module including
An operation member, a display member, a battery, a communication unit,
A portable terminal comprising: a housing that houses the camera module, the display member, the battery, and the communication unit, and that has a thickness limited to approximately the height of the camera module.

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