JPWO2006035580A1 - Lens barrel, and imaging apparatus, camera, and portable device including the lens barrel - Google Patents

Abstract

A lens barrel having a lens barrier opening / closing mechanism with good operability and a thinner camera can be obtained while the bending optical system using the reflecting member can be thinned. An aperture through which subject light is incident, a lens barrier, a plurality of lens groups, a reflecting member that bends the subject light in a substantially right angle direction, and an image sensor that photoelectrically converts the subject light. Among the lens barrels configured to perform zooming by moving a predetermined lens group in the optical axis direction, at least one lens group is configured to move according to the movement of a screwing member screwed to a lead screw, The screw member is movable to a position exceeding the moving range of the lens group, and a lens barrel configured to open and close the lens barrier by moving the screw member at a position exceeding the moving range of the lens group.

Description

  The present invention relates to a lens barrier driving mechanism provided in an opening, which is a subject light incident portion, of a lens barrel of an imaging optical system configured to bend a subject light substantially at a right angle and guide the light to an imaging device.

  Conventionally, in a so-called digital camera in which a signal obtained by photoelectrically converting a subject image by an imaging device is converted into a digital signal, subjected to predetermined processing, and electronically recorded on a recording medium, a reflecting member is disposed in the imaging optical system. An imaging optical system is known in which the optical axis is bent in a direction substantially parallel to the front surface of the camera. It is also known that a lens barrier that opens and closes by moving the opening on the front surface of the camera including the bending optical system where the subject light enters to a position where it is exposed and a position where it is exposed is also known.

  As a lens barrier opening / closing drive mechanism of a camera equipped with such a bending optical system, a zooming cam cylinder arranged around the optical axis and in the circumferential direction of the lens group is used. Among them, a device that uses a predetermined region for opening and closing the lens barrier is known.

Further, there is disclosed a device that manually rotates an operation ring provided on the front surface of the camera, rotates a lens barrier engaged with the operation ring in response to the rotation operation, and opens and closes the opening ( For example, see Patent Document 1).
JP 2001-11868 (FIGS. 6 to 10)

  The above-described camera using the bending optical system can form the front of the camera flat without the optical system protruding from the front of the camera body even if the bending optical system is a variable power system.

  However, among the rotation regions of the zooming cam cylinders arranged in the circumferential direction of the lens group described above, one that uses a predetermined region for opening and closing the lens barrier is operated by one-touch operation members such as a power-on switch. The lens barrier is open, that is, the camera is ready to shoot, and the operability is good, but the zooming cam cylinder must be placed around the optical axis outside the lens group constituting the optical system. The lens barrel diameter of the system increases, which is an obstacle to making the camera thinner.

  The lens barrier opening / closing drive mechanism described in Patent Document 1 described above manually and sequentially rotates an operation ring provided around the opening on the front of the camera, compared to a lens barrier that is electrically opened and closed. There is a problem that the operability is inferior.

  In view of the above problems, the present invention includes a lens barrel that includes a lens barrier opening / closing mechanism that can be thinned and has good operability, and a lens barrel that can be thinned using a reflecting member. Thus, the object is to obtain a thinner camera.

  The above object is solved by the following configuration.

  1) An opening through which subject light is incident, an open state that exposes the opening, a closed lens barrier that covers the opening, a plurality of lens groups that guide the subject light, and the subject light at substantially right angles A reflecting member that bends in a direction, and an image sensor that photoelectrically converts subject light guided by the plurality of lens groups and the reflecting member, and a predetermined lens group of the plurality of lens groups is arranged in an optical axis direction. In the lens barrel configured to perform zooming by moving to at least one lens group, at least one of the predetermined lens groups moving in the optical axis direction moves according to the movement of a screwing member screwed to the lead screw. The screwing member is configured to be movable up to a position exceeding the moving range of the one lens group, and by moving the screwing member at a position exceeding the moving range of the one lens group. Lens barrel, characterized by being configured so as to open and close the serial lens barrier.

  2) The lens barrier is biased in a direction to expose the opening by a biasing member, and covers the opening by moving the screwing member in a direction against the biasing force of the biasing member. 1) The lens barrel in the closed state.

  3) The lens barrel according to 1) or 2), wherein the predetermined lens group moving in the optical axis direction is urged in a direction away from each other by the urging member.

  4) Among the plurality of lens groups, the lens group disposed between the reflecting member and the imaging element is positioned in a direction perpendicular to each optical axis by two guide shafts 1) To 3).

  5) An imaging device comprising the lens barrel according to any one of 1) to 4).

  6) A camera comprising the lens barrel according to any one of 1) to 4).

  7) A mobile device with a camera function, comprising the lens barrel according to any one of 1) to 4).

  According to the present invention, the screwing member to be screwed with the lead screw is moved, and the lens group is moved in accordance therewith to perform zooming. The screwing member is moved to a position exceeding the moving range of the lens group. By enabling the lens barrel to open and close the lens barrier by moving the screw member beyond the moving range of the lens group, the drive direction of each part can be made parallel to the optical axis. Thus, the lens barrel can be configured to be thin, and the lens barrier can be opened and closed and zoomed without adding a new actuator. Can be obtained.

It is a figure which shows an example of the internal arrangement | positioning of the main structural unit of the camera provided with the lens barrel which concerns on this invention. It is a perspective view of the unit state of the lens barrel concerning the present invention. 1 is a cross-sectional view showing a foldable imaging optical system capable of zooming and encapsulated in a lens barrel according to the present invention. It is a schematic diagram which shows the moving mechanism of a 2nd lens group and a 4th lens group. It is a schematic diagram showing an example of a lens barrier opening and closing mechanism of the lens barrel according to the present invention. It is a schematic diagram which shows the other example of the lens barrier opening / closing mechanism concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st lens group 2 2nd lens group 3 3rd lens group 4 4th lens group 5 Optical filter 6 Imaging element 9 Shutter unit 10 Main trunk A
11 Main trunk B
15 Guide shaft 16 Guide shaft 18 Compression coil spring 20 First motor 21 Second motor 22 Screwing member (nut)
50 Lens barrel 51 Aperture 60 Lens barrier 62 Spring A
64 Lens barrier driving member 67 Spring B
100 cameras

  Hereinafter, the present invention will be described in detail with reference to embodiments, but the present invention is not limited thereto.

  FIG. 1 is a diagram showing an example of an internal arrangement of main constituent units of a camera 100 including a lens barrel according to the present invention. FIG. 3 is a perspective view of the camera 100 as viewed from the subject side.

  As shown in the figure, in the camera 100, a lens barrel 50 according to the present invention including a foldable imaging optical system capable of zooming is arranged vertically on the right side as shown, and a lens opening 51 for taking in a subject light beam is provided. Arranged as shown. Furthermore, a lens barrier is provided in which the lens opening 51 is exposed and the lens barrier 51 is closed.

  Reference numeral 52 denotes a flash light emission window. Reference numeral 53 denotes a flash unit including a reflector, a xenon tube, other main capacitors, a circuit board, and the like disposed behind the flash light emission window. Reference numeral 54 denotes a card-type image recording memory. A battery 55 supplies power to each part of the camera. The image recording memory 54 and the battery 55 can be inserted and removed from a lid (not shown).

  A release button 56 is disposed on the upper surface of the camera. When the first button is pushed, a shooting preparation operation of the camera, that is, a focusing operation and a photometric operation are performed, and a shooting exposure operation is performed by pushing the second button. A main switch 57 is a switch for switching the camera between an operating state and a non-operating state. When switched to the operating state by the main switch 57, the lens barrier (not shown) is opened and the operation of each part is started. When the main switch 57 is switched to the non-operating state, the lens barrier is closed and the operation of each unit is terminated.

  On the back side of the camera, an image display unit 58, which is composed of an LCD or an organic EL and displays images and other character information, is disposed. Although not shown, a zoom button for zooming up and down, a playback button for playing back a captured image, a menu button for displaying various menus on the image display unit 58, and a desired function are selected from the display. An operation member such as a selection button is arranged.

  Further, although not shown in the drawing, each main component unit is connected to each part, and a circuit board on which various electronic components are mounted is arranged to drive and control each main component unit.

  Further, although not shown, an external input / output terminal, a strap attaching portion, a tripod seat and the like are provided.

  FIG. 2 is a perspective view of the lens barrel 50 according to the present invention in a unit state.

  As shown in the figure, the lens barrel 50 is arranged on the main barrel A10 in the vicinity of the lens opening 51 with a lens barrier 60 supported by a support shaft 61. The lens barrier 60 rotates in the direction indicated by the arrow about the support shaft 61, and is switched between a position where the lens opening 51 is exposed and a position where the lens opening 51 is covered to perform an opening / closing operation. Reference numeral 6 denotes an image sensor, 20 denotes a first motor that moves one lens group, and 21 denotes a second motor that moves the other lens group. The first motor 20, the second motor 21, and the image sensor 6 are connected to a printed circuit board (not shown) and are individually controlled and driven.

  FIG. 3 is a cross-sectional view showing a foldable imaging optical system capable of zooming contained in a lens barrel 50 according to the present invention. This figure shows a state at the time of widening, which is cut along a plane including two optical axes before and after bending.

  As shown in the figure, OA is the optical axis before bending, and OB is the optical axis after bending. The outer side of the lens barrel 50 is composed of a main cylinder A10 and a main cylinder B11.

  Reference numeral 1 denotes a first lens group. The first lens group 1 includes a prism 11 that is a reflection member that bends the optical axis OA in a substantially right angle direction, a lens 11 that is disposed toward the subject with the optical axis OA, and a prism 12. The lens 13 is disposed with the optical axis OB bent by the optical axis as the optical axis. The first lens group 1 is a lens group fixed to the main body A10.

  In front of the lens 11 constituting the first lens group 1 (on the subject light incident side), a lens barrier 60 is disposed that opens to expose the opening and closes to cover the opening. The lens barrier 60 rotates while sliding on the rail 10r formed on the main body A10, and is in an open state and a closed state that covers the opening.

  Reference numeral 2 denotes a second lens group, which is incorporated in the second lens group frame 2k. The second lens group is a lens group that moves together with the second lens group frame 2k during zooming (hereinafter also referred to as zooming).

  Reference numeral 3 denotes a third lens group, which is incorporated in the third lens group frame 3k. The third lens group 3 is a lens group in which the third lens group frame 3k is fixed by the main body A10 and does not move during zooming.

  Reference numeral 4 denotes a fourth lens group, which is incorporated in the fourth lens group frame 4k. The fourth lens group is a lens group that moves integrally with the fourth lens group lens frame 4k during zooming and during focus adjustment (hereinafter also referred to as focusing).

  Reference numeral 5 denotes an optical filter in which an infrared light cut filter and an optical low-pass filter are stacked, and is assembled to the main body A10. Reference numeral 6 denotes an image sensor, which uses a charge coupled device (CCD) type image sensor, a complementary metal-oxide semiconductor (CMOS) type image sensor, or the like. The image sensor 6 is assembled to the attachment member 8, and the attachment member 8 is assembled to the main body A 10 together with the image sensor 6. A flexible printed circuit board 7 is connected to the image sensor 6 and is connected to other circuits in the camera. Reference numeral 9 denotes a shutter unit, which is fixed to the main body A10 in the same manner as the third lens group frame 3k.

  The second lens group 2 and the fourth lens group 4 are moved by a set amount from the position in the illustrated wide state toward the third lens group 3 for zooming. Further, the fourth lens group 4 is focused by further moving from the position moved by zooming.

  FIG. 4 is a schematic diagram showing a moving mechanism of the second lens group 2 and the fourth lens group 4. This figure shows a state in which the second lens group 2 and the fourth lens group 4 are in the wide position. In the following drawings, in order to avoid duplication of explanation, the same reference numerals are given to the same functional members.

  As shown in the figure, the guide shaft 15 is fitted through the sleeve 2s formed integrally with the second lens group frame 2k and the sleeve 4s formed integrally with the fourth lens group frame 4k. Match. Further, the guide shaft 16 engages with a rotation locking portion 2m formed integrally with the second lens group lens barrel 2k and a rotation locking portion 4m formed integrally with the fourth lens group lens frame 4k. Are arranged. Thereby, the second lens group lens frame 2k and the fourth lens group lens frame 4k are slidable along the guide shafts 15 and 16 in the direction of the optical axis OB.

  The sleeve 2s is preferably formed to extend to the side of the prism 12 as shown in FIG. By doing so, the sleeve 2s can secure a sufficient fitting amount while keeping the entire length of the lens barrel as it is, and the second lens group lens frame 2k, that is, the second lens group 2 can be made smoother. It is possible to move to.

  The guide shafts 15 and 16 also fit through the shutter unit 9 and the third lens group frame 3k. By doing in this way, the 2nd lens group 2, the 3rd lens group 3, and the 4th lens group 4 can be positioned by the pair of guide shafts in the direction perpendicular to the optical axis. It is prevented from being localized in a shifted state with respect to the second lens group 2 and the fourth lens group 4.

  Further, the second lens group frame 2k has a protrusion 2t formed on the sleeve 2s, and the fourth lens group frame 4k has a protrusion 4t formed on the sleeve 4s. The protrusions 2t and 4t are biased. The compression coil spring 18 which is a member is biased in a direction away from each other. Reference numeral 17 denotes a shaft for preventing the compression coil spring 18 from buckling, and is disposed through the protrusions 2t and 4t.

  Reference numeral 20 denotes a first motor, 21 denotes a second motor, both of which are stepping motors. The first motor 20 has a lead screw 20r, and the second motor 21 has a lead screw 21r. A screwing member (also referred to as a nut) 22 that is screwed around the entire circumference in the rotation direction is screwed into the lead screw 20r. The lead screw 21r is screwed with a screwing member (also referred to as a nut) 24 that is screwed around the entire circumference in the rotation direction. The nuts 22 and 24 are engaged with a rotation stopper (not shown) and are configured to be movable in the direction of the optical axis OB by the rotation of the lead screw.

  As shown in the figure, the nut 22 abuts against a protrusion 2t formed integrally with the second lens group frame 2k, and stops the second lens group frame 2k against the urging force of the compression coil spring 18. Thus, the position of the second lens group frame 2k in the optical axis OB direction is determined. Similarly, as shown in the drawing, the nut 24 abuts against a protrusion 4t formed integrally with the fourth lens group lens frame 4k, and resists the urging force of the compression coil spring 18 to cause the fourth lens group lens frame 4k to move. By stopping, the position of the fourth lens group lens frame 4k in the optical axis OB direction is determined.

  Thereby, the nut 22 moves in the optical axis OB direction by the rotation of the lead screw 20r of the first motor 20, and the second lens group frame 2k can be stopped at a desired position in the optical axis OB direction. Similarly, the rotation of the lead screw 21r of the second motor 21 moves the nut 24 in the optical axis OB direction, and the fourth lens group lens frame 4k can be stopped at a desired position in the optical axis OB direction. That is, by controlling the rotation direction and the rotation amount of the first motor 20 and the second motor 21, the second lens group 2 and the fourth lens group 4 are moved independently to perform zooming, and further, the second motor The fourth lens group 4 is moved by 21 to perform focusing.

  That is, the nut 24 of the second motor 21 performs zooming by moving between a wide position indicated by a solid line and a tele position indicated by a broken line, and performs focusing by moving slightly around the position.

  In the figure, for the sake of easy understanding, the positions of the first motor 20 and the second motor 21 are moved out of the lens barrel. . Although not shown, a position sensor for detecting the presence of the second lens group 2 and a position sensor for detecting the presence of the fourth lens group 4 are arranged. For example, a photo interrupter is used as the position sensor. In this position sensor, the shielding portions formed on the second lens group lens frame 2k and the fourth lens group lens frame 4k are respectively shielded between the light projecting / receiving systems of the position sensors, or the light projecting / receiving system of the position sensor. The position of the lens group is controlled by controlling the rotation direction and amount of rotation of each of the two stepping motors based on the switching position from the shielding state to the non-shielding state. To be done.

  Further, the nut 22 of the first motor 20 is configured so as to perform lens barrier opening / closing control described later. Hereinafter, the movement of the nut 22 will be described.

  The nut 22 of the first motor 20 is set so as to be movable to a position exceeding the moving range of the second lens group 2. During zooming, it moves between the wide position indicated by the solid line and the tele position indicated by the broken line (range Y to Z in the figure), and can move to the position indicated by the alternate long and short dash line (range X to Y in the figure) beyond this range It has become. In the range of X to Y in the figure, the second lens group lens frame 2k comes into contact with the stopper 10s and stops. The movement of the nut 22 in the range of X to Y shown in the drawing allows the lens barrier opening / closing operation described later to be performed.

  FIG. 5 is a schematic view showing an example of a lens barrier opening / closing mechanism of the lens barrel according to the present invention. FIG. 4A shows the opened state of the lens barrier 60, and FIG. 4B shows the closed state of the lens barrier 60.

  In the open state of the lens barrier 60 shown in FIG. 5A, the lens barrier 60 is urged in the opening direction by the spring A62, and rotates about the support shaft 61 to form a pin formed on the main cylinder A10. It is stopped in contact with A63 and with the opening 51 exposed.

  Reference numeral 64 denotes a lens barrier driving member. When the lens barrier driving member 64 moves in the right direction from the illustrated state, the contact portion 64t formed on the lens barrier driving member 64 is engaged with the pin B65 formed on the lens barrier 60. Yes. Further, the pin C66 formed on the lens barrier driving member 64 engages with the nut 22 screwed to the lead screw 20r of the first motor 20 at the positions Y to X in the drawing, and the nut 22 is moved from the Y position to the X position. By moving to the position, the lens barrier driving member 64 is moved in the right direction in the figure from the state shown in the figure.

  That is, when the nut 22 is on the left side of the Y position (in the range of Y to Z in FIG. 4), the nut 22 and the pin C66 are separated from each other, and the lens barrier is kept open.

  On the other hand, when the first motor 20 is driven and the nut 22 is moved from the Y position to the X position, the nut 22 is engaged with the pin C66 and the lens barrier driving member 64 is moved to the right in the drawing. Thereby, the contact part 64t of the lens barrier driving member 64 presses the pin B65 of the lens barrier 60, and rotates the lens barrier 60 against the urging force of the spring A62.

  When the nut 22 is moved to the X position as shown in FIG. 5B, the lens barrier 60 is in a closed state covering the opening. When the first motor 20 is stopped in this state, the closed state is changed. Maintained.

  The operation from the closed state to the open state is performed by driving the first motor 20 and moving the nut 22 from the X position to the Y position, so that the lens barrier 60 is rotated by the urging force of the spring A62. The open state shown in FIG.

  That is, when mounted on the camera, when the main switch is turned on so as to be in the operating state, the first motor 20 is driven from the state shown in FIG. By moving the lens barrier 60 to the position, the lens barrier 60 is brought into the open state shown in FIG. 5A by the biasing force of the spring A62, and the nut 22 is further moved from the Y position to the left in the figure (range YZ shown in FIG. 4). By doing so, zooming can be performed from the wide state (see FIG. 4). On the other hand, when the main switch is turned off so as to be in the non-operating state, the nut 22 is first moved to the Y position and returned to the wide state, and further the nut 22 is moved from the Y position to the X position direction, With the second lens group 2 left behind, the lens barrier 60 is rotated in the closing direction against the urging force of the spring A62, and the nut 22 is stopped at the X position, whereby the closed state shown in FIG. can do.

  As described above, the nut screwed to the lead screw is moved, and the lens group is moved according to this to perform zooming, and this nut can be moved to a position beyond the moving range of the lens group. By configuring the nut barrier to open and close by moving the nut lens group beyond the moving range, the drive direction of each part can be made parallel to the optical axis after bending, thereby making the lens barrel The camera can be configured to be thin, and the lens barrier can be opened and closed and zoomed without adding a new actuator. Thus, it is possible to obtain a camera equipped with a lens barrel with good operability at low cost.

  In addition, when the camera is not operating, the lens group frame and the nut are disengaged, so that even when subjected to an impact such as a drop, the impact is not transmitted to the nut, lead screw, and motor, and damage to these can be prevented. A camera can be obtained.

  The protrusion 4t and the nut 24 formed on the sleeve 4s of the fourth lens group lens frame 4k are also configured to move the nut 24 to a position beyond the moving range of the fourth lens group 4 when the camera is not operating. It is desirable to do. In this way, similarly, when an impact such as a drop is applied, the impact is not transmitted to the nut 24, the lead screw 21r, and the motor 21, and damage to these can be prevented.

  FIG. 6 is a schematic view showing another example of the lens barrier opening / closing mechanism according to the present invention. FIG. 4A shows the opened state of the lens barrier 60, and FIG. 4B shows the closed state of the lens barrier 60.

  The difference between the lens barrier opening / closing mechanism shown in FIG. 5 and the lens barrier opening / closing mechanism shown in FIG. 5 is that the lens barrier driving member 64 and the lens barrier 60 are not directly engaged but are engaged via the spring B67. Therefore, only the parts different from FIG. 5 will be described.

  The spring B67 shown in the figure is a tension coil spring having a high so-called spring constant, a small amount of elongation, and a biasing force larger than that of the spring A62. The open state shown in FIG. The positional relationship between the lens barrier 60 and the lens barrier driving member 64 is set to be a free length and no urging force is applied. For this reason, the lens barrier 60 is opened by the urging force of the spring A62. On the other hand, when the nut 22 is moved to the position X in the figure and the lens barrier driving member 64 is in the state shown in FIG. 5B, the spring B67 is extended, and the urging force of the spring B67 is larger than the urging force of the spring A62. The lens barrier 60 is closed. The lens barrier 60 is stopped in a closed state by a pin D68 formed on the main body A.

  With this configuration, it is possible to obtain a lens barrier opening / closing mechanism that is not damaged even when a foreign object or the like is caught in the operation region of the lens barrier 60.

  The lens barrel of the present invention can be applied not only to a normal digital camera but also to a camera unit built in a mobile phone or the like. The camera in the present invention is a camera module built in a mobile terminal or the like. Of course, it also includes. In addition, the description has been given by taking the camera in which the lens barrel is arranged in the vertical direction as an example, but it is needless to say that the present invention can also be applied to a camera in which the lens barrel is arranged in the horizontal direction.

Claims (7)

  An opening through which subject light is incident; an open state that exposes the opening; a closed lens barrier that covers the opening; a plurality of lens groups that guide the subject light; and the subject light in a substantially perpendicular direction. A reflecting member that bends; and an imaging device that photoelectrically converts subject light guided by the plurality of lens groups and the reflecting member, and moves a predetermined lens group in the optical axis direction among the plurality of lens groups. In the lens barrel configured to perform zooming, at least one of the predetermined lens groups moving in the optical axis direction is configured to move according to the movement of a screwing member screwed to the lead screw. The screwing member is configured to be movable to a position exceeding the moving range of the one lens group, and the screwing member moves by moving the screwing member at a position exceeding the moving range of the one lens group. Lens barrel, characterized by being configured so as to open and close the Nzubaria.   The lens barrier is biased in a direction in which the opening is exposed by a biasing member, and the screwing member moves in a direction against a biasing force of the biasing member to cover the opening. The lens barrel according to claim 1, wherein:   The lens barrel according to claim 1 or 2, wherein the predetermined lens group moving in the optical axis direction is urged in a direction away from each other by an urging member.   Among the plurality of lens groups, the lens group disposed between the reflecting member and the imaging element is positioned in a direction orthogonal to each optical axis by two guide shafts. The lens barrel according to any one of claims 1 to 3, wherein:   An imaging apparatus comprising the lens barrel according to any one of claims 1 to 4.   A camera comprising the lens barrel according to any one of claims 1 to 4.   A portable device with a camera function, comprising the lens barrel according to any one of claims 1 to 4.

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