JP5350035B2 - Lens barrel and optical apparatus having the same - Google Patents

Description

  The present invention relates to a lens barrel and an optical apparatus having the same, and is suitable for moving a lens moving frame that holds a lens group along an optical axis or in a direction perpendicular to the optical axis in a video camera, a digital still camera, or the like. It is a thing.

  Imaging devices (optical devices) such as digital cameras and video cameras move the lens frame in the direction of the optical axis or in the direction orthogonal to the optical axis to perform zooming and focus adjustment, and to correct image blur. Etc. As a driving means for moving the lens frame, one using a vibration type linear actuator (ultrasonic motor) is known. In a vibration type linear actuator, a vibration member (vibrator) whose vibration is excited by a piezoelectric element and a contact member (relative motion member) that is in pressure contact with the vibration member and relatively moves are relatively moved in a linear direction.

  There is known a drive device that drives a driven object using such a vibration type linear actuator (Patent Document 1). In the drive motor of Patent Document 1, a vibration absorbing member made of butyl rubber is used in order to prevent the generation of noise caused by the vibration generated from the base member when driving the vibration type linear actuator and the decrease in driving efficiency. . Specifically, a relative motion member (slider) is fixed to the base member via a vibration absorbing member. At this time, a vibration absorbing member is bonded to the entire surface in order to fix both. As a result, the vibrator and the relative motion member are relatively moved while reducing the noise caused by the vibration generated from the base member.

JP 2000-324865 A

  In the ultrasonic motor (drive motor) of Patent Document 1, a vibration absorbing member is provided on the entire surface between the base member and the relative motion member, and these members are joined with an adhesive. And it is reduced that the vibration which generate | occur | produced in the relative motion part agent is absorbed by the vibration absorption member, and is transmitted to a base member. As a result, the vibration generated in the base member is reduced and the generation of noise is reduced. However, since the vibration absorbing member is bonded to fix the contact member in the drive motor of the cited document 1, it takes time to assemble, and when fixing to the inner wall of the lens barrel, fixing is difficult and design freedom There was a problem that the temperature was low.

  The present invention provides a lens that can move the moving lens frame with high accuracy without play when the moving lens frame is moved by the vibration type linear actuator, while the noise during the movement is small and the entire apparatus is downsized. It is an object of the present invention to provide a lens barrel and an optical apparatus having the same.

The lens barrel of the present invention vibrates with an optical element holding member that holds and moves an optical element, guide means for guiding the movement of the optical element holding member, and a base member that holds the guide means. A vibration type linear actuator composed of a vibration member and a contact member in contact with the vibration member, wherein the contact member has vibration absorption members attached to both ends in the moving direction thereof, and the vibration absorption member Are fixed to the base member or the optical element holding member , and the vibration absorbing member is configured to position the contact member in an optical axis direction of the optical element and a direction orthogonal to the optical axis. And is attached so as to cover the end of the contact member .

  According to the present invention, when the moving lens frame is moved by the vibration type linear actuator, it is possible to move the moving lens frame with high accuracy without play while reducing noise during movement and reducing the size of the entire apparatus. A lens barrel that can be obtained is obtained.

FIG. 3 is an explanatory diagram of a lens barrel of Embodiment 1 of the present invention. Sectional drawing when the lens barrel of Example 1 is cut along a plane parallel to the optical axis. 2 is an exploded perspective view of the lens barrel of Embodiment 1. FIG. Sectional drawing when the lens barrel of Example 1 is cut along a plane perpendicular to the optical axis of the first vibration type linear actuator unit Sectional drawing when the lens barrel of Example 1 is cut by a plane perpendicular to the optical axis of the first vibration type linear actuator portion. FIG. 3 is an exploded view of a slider fixing portion of the first vibration type linear actuator in the lens barrel of the first embodiment. FIG. 3 is a diagram illustrating a slider fitting portion of a first vibration type linear actuator in the lens barrel of the first embodiment. Sectional drawing when cut | disconnecting in the surface parallel to the optical axis of the 1st vibration type linear actuator in the lens-barrel of Example 1. FIG. FIG. 4 is an exploded perspective view of a slider fixing portion of a second vibration type linear actuator in the lens barrel of the first embodiment. FIG. 6 is a perspective view of a slider fixing portion of a second vibration type linear actuator in the lens barrel of the first embodiment. Sectional drawing when cut | disconnecting in the surface parallel to the optical axis of the 2nd vibration type linear actuator in the lens-barrel of Example 1. FIG. FIG. 3 is a block diagram of a main part of an optical apparatus having the lens barrel of the first embodiment. FIG. 6 is a perspective view of the first vibration type linear actuator in the lens barrel of Embodiment 1 on the second lens holding member side. Sectional drawing when cut | disconnecting in the surface parallel to the optical axis of the 1st vibration type linear actuator in the lens-barrel of Example 1. FIG.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The lens barrel of the present invention is shown as follows with reference to reference numerals attached to the respective members described later. The lens barrel of the present invention holds optical elements (second lens unit 2 and fourth lens unit 4) and moves in the optical axis direction with optical element holding members (second lens holding frame 12 and fourth lens holding frame). 14). Guide means (guide bars 10 and 11) for moving and guiding the optical element holding member and a fixed base member (first lens holding member 6 and rear barrel 5) for holding the guide means are provided.

  Furthermore, a vibration type linear actuator (ultrasonic motor) including a vibration member (vibrators 19 and 35) in which vibration is excited by an electro-mechanical energy conversion action and a contact member (sliders 18 and 34) in contact with the vibration member. ). The contact member has vibration absorbing members attached to both ends in the moving direction. And it is being fixed to the base member via the vibration absorption member. Here, the vibration absorbing member is a thin film that positions the optical axis direction and the optical axis orthogonal direction of the optical element in a concave cap shape, and is attached so as to cover the end of the contact member. In addition, the contact member is fitted into a concave first fitting portion 6 a having one end formed on the first lens holding member (first base member) 6 through a vibration absorbing member. The other end is fitted and fixed to a concave second fitting portion 5 a formed in the rear barrel (second base member) 5.

[Example]
FIGS. 1A to 1D are explanatory views when the lens barrel of the first embodiment of the present invention is viewed from the four directions of the front side, the right side, the rear, and the left side with the exterior removed. FIG. 2 is a cross-sectional view taken along a plane including the optical axis of the lens barrel. FIG. 3 is an exploded perspective view of the lens barrel. FIG. 4 is a cross-sectional view of the first vibration type linear actuator section constituting the lens barrel taken along a plane perpendicular to the optical axis. FIG. 5 is a cross-sectional view taken along a plane perpendicular to the optical axis of the second vibration type linear actuator portion constituting the lens barrel.

  6 is an explanatory diagram of one slider portion of FIG. 1, FIGS. 7A and 7B are explanatory diagrams of the positional relationship between the slider of FIG. 1 and the base member (5, 6), and FIG. 8 is a lens barrel. It is the elements on larger scale of the 1st vibration type linear actuator which constitutes. 9 is an explanatory view of the other slider portion of FIG. 1, FIG. 10 is an explanatory view after the other slider portion of FIG. 1 is assembled, and FIG. 11 is a partially enlarged view of the second vibration type linear actuator constituting the lens barrel. FIG. FIG. 12 is a principal block diagram of the optical apparatus of the present embodiment. FIG. 13 is a perspective view of the first vibration type linear actuator in the lens barrel of the present invention on the second lens holding member side. FIG. 14 is a cross-sectional view of the main part when the lens barrel of the present invention is cut along a plane parallel to the optical axis of the first vibration type linear actuator.

  In these drawings, in order from the object side to the image side, 1 is a fixed first lens unit, and 2 is a second lens unit (optical element) that moves in the optical axis direction for zooming. 15 is a light quantity adjustment unit, 3 is a fixed third lens unit, and 4 is a fourth lens unit that moves in the optical axis direction for correction of image plane variation accompanying zooming and focus adjustment. The first to fourth lens units 1 to 4 constitute a part of the zoom lens. Reference numeral 5 denotes a rear barrel (base member) that holds an image sensor and a low-pass filter (LPF), which will be described later, and is fixed to a camera body (not shown). Reference numeral 6 denotes a first lens holding member (base member) that holds the first lens unit 1 and is fixed to the rear barrel 5 by screws 7, 8, and 9. Reference numerals 10 and 11 denote guide bars (guide members) (guide means) held substantially in parallel with the optical axis direction by the rear barrel 5 and the first lens holding member 6. Reference numeral 12 denotes a second lens holding member (optical element holding member) that holds the second lens unit 2, and a mask 32 that cuts unnecessary light is fixed thereto.

  The second lens holding member 12 is engaged with the guide bar guide bar (guide means) 10 in the engaging portion 12a and guided in the optical axis direction, and is engaged with the guide bar (guide means) 11 in the engaging portion 12b. doing. Thereby, the rotation of the second lens holding member 12 around the guide bar 10 is prevented. A third lens holding member 13 holds the third lens unit 3 and is fixed to the rear barrel 5 with screws 16. Reference numeral 14 denotes a fourth lens holding member for holding the fourth lens unit 4. The fourth lens holding member 14 is engaged with the guide bar 11 in the engaging portion 14 a and guided in the optical axis direction, and is engaged with the guide bar 10 in the engaging portion 14 b. ing. As a result, the rotation of the fourth lens holding member 14 around the guide bar 11 is prevented. The light amount adjustment unit 15 has an outer shape that is longer in the vertical direction (first direction) than in the left-right direction (second direction) when viewed from the optical axis direction. The light quantity adjustment unit 15 is fixed to the rear barrel 5 with screws 17.

  Reference numeral 18 denotes a slider (contact member) configured by joining a magnet and a friction material. Reference numeral 19 denotes a vibrator (vibrating member) composed of an electro-mechanical energy conversion element and a plate-like elastic member whose vibration is excited by the electro-mechanical energy conversion element. Here, the elastic member of the vibrator 19 is a ferromagnet, and the ferromagnet attracts the magnet of the slider 18, so that the optical axis on the pressure contact surface 18 a of the friction material of the slider 18 and the elastic member of the vibrator 19 The pressure contact surfaces 19a and 19b formed at two places in the direction are pressure contacted. In the first vibration type linear actuator constituted by the slider 18 and the vibrator 19, two frequency signals (pulse signals or alternating signals) having different phases are input to the electromechanical energy conversion element via the flexible wiring board 20. Is done.

  As a result, a substantially elliptical motion is generated on the pressure contact surfaces 19 a and 19 b of the vibrator 19, and a driving force in the optical axis direction is generated on the pressure contact surface 18 a of the slider 18. Reference numeral 21 denotes a spacer to which the vibrator 19 is fixed, and 22 denotes a leaf spring to which the spacer 21 is fixed. The leaf spring 22 has a shape that is not easily deformed in the in-plane direction of the plate surface and is easily deformed in a direction perpendicular to the plate surface. Further, the leaf spring 22 can be easily deformed in the rotational direction around an arbitrary axis included in the surface thereof, and the deformation causes the pressure contact surfaces 19 a and 19 b of the vibrator 19 to be in contact with the pressure contact surface 18 a of the slider 18. And keep them parallel. Since the leaf spring 22 is not easily deformed in the in-plane direction, the displacement of the vibrator 19 in the optical axis direction (that is, the driving direction) is limited.

  Next, a method for fixing the slider 18 to the base member (5, 6) will be described. The first lens holding member (first base member) 6 is formed with a fitting portion (first fitting portion) 6 a into which one end of the slider 18 is fitted. The rear group barrel (second base member) 5 is formed with a fitting portion (second fitting portion) 5 a into which the other end of the slider 18 is fitted. Reference numerals 26 and 27 denote vibration absorbing members made of butyl rubber, which are thin and concave cap shapes. With this shape, the vibration absorbing members 26 and 27 position the slider 18 in the optical axis direction and the optical axis orthogonal direction. The vibration absorbing members 26 and 27 are put on the slider 18 as shown in FIG. 6 to form a first slider unit. At this time, dimensions are set so that the concave portions of the vibration absorbing members 26 and 27 are press-fitted into the slider 18. The first slider unit (18, 26, 27) is first inserted into either the fitting part 6 a of the first lens holding frame 6 or the fitting part 5 a of the rear barrel 5. Here, the vibration absorbing member 27 side of the first slider unit is inserted into the fitting portion 5a of the rear lens barrel 5, and the entrance of the fitting portion 5a is chamfered so that the slider unit can be easily inserted.

  When the rear group barrel 5 and the first lens holding member 6 are combined, the end of the first slider unit (18, 26, 27) on the vibration absorbing member 26 side is inserted into the fitting portion 6a. The entrance of the fitting portion 6a is also chamfered so that the first slider unit can be easily inserted. In this state, by fixing the first lens holding member 6 and the rear group barrel 5 with screws 7, 8 and 9, the first slider unit is fixed between the first lens holding member 6 and the rear barrel 5. Is done. At this time, since the fitting portions at both ends are dimensioned so that the side surfaces are press-fitted, the slider 18 is held without play. Reference numeral 28 denotes a scale for detecting the movement amount (position) of the second lens holding member 12, and is fixed to the groove 12 d formed in the second lens holding member 12 by adhesion or the like.

  The leaf spring 22 is fixed to the second lens holding member 12 by screws 24 and 25. The vibrator 19 is fixed to the second lens holding member 12 via a leaf spring 22. Reference numeral 29 denotes a light projecting / receiving element that projects light onto the scale 28 and receives reflected light from the scale 28 to detect the amount of movement of the second lens holding member 12. The light projecting / receiving element 29 and the scale 28 constitute a first linear encoder as a detector for detecting the amount of movement of the second lens holding member 12. Reference numeral 30 denotes a flexible wiring board for inputting / outputting signals to / from the light projecting / receiving element 29, and is fixed to the first lens holding member 6 by screws 31.

  The second lens holding member 12 is provided with stoppers 12e and 12f. The gaps between the stopper portions 12e and 12f and the rear barrel 5 and the first lens holding member 6 are set to be L2 over the entire movable range of the second lens holding member 12. Further, the minimum gap between the spacer 21 and the second lens holding member 12 is L1. At this time, there is a relationship of L1> L2 between L1 and L2. The first vibration type linear actuator has a guide bar 10, a vibrator 19 and a slider 18, and the first linear encoder has a light projecting / receiving element 29 and a scale 28. As shown in FIG. 1, these are the right side surface of the plane which is one of the outer surfaces closest to the optical axis position of the light amount adjustment unit 15 among the outer peripheral surfaces of the light amount adjustment unit 15 when viewed from the front in the optical axis direction. It is arranged close to (a straight right long side when viewed in the optical axis direction). The first vibration type linear actuator (10, 18, 19) and the first linear encoder (28, 29) are disposed adjacent to the guide bar 10 so as to sandwich the guide bar 10 in the vertical direction. Yes.

  Reference numeral 34 denotes a slider (contact member) configured by joining a magnet and a friction material. The slider 34 is fixed to the fourth lens holding member 14. The vibrator 35 includes an electro-mechanical energy conversion element and a plate-like elastic member whose vibration is excited by the electro-mechanical energy conversion element. Here, the elastic member of the vibrator 35 is a ferromagnetic body, and when the ferromagnetic body attracts the magnet of the slider 34, the optical axis of the friction member pressure contact surface 34a of the slider 34 and the elastic member of the vibrator 35 is increased. The press contact surfaces 35a and 35b formed at two places in the direction are pressed. In the second vibration type linear actuator composed of the slider 34 and the vibrator 35, two frequency signals (pulse signals or alternating signals) having different phases are input to the electromechanical energy conversion element via the flexible wiring board 36. Is done.

  Thereby, a substantially elliptical motion is generated on the pressure contact surfaces 35 a and 35 b of the vibrator 35, and a driving force in the optical axis direction is generated on the pressure contact surface 34 a of the slider 34. 37 is a spacer to which the vibrator 35 is fixed, and 38 is a leaf spring to which the spacer 37 is fixed. The leaf spring 38 has a shape that is not easily deformed in the in-plane direction of the plate surface and is easily deformed in a direction perpendicular to the plate surface. The leaf spring 38 can be easily deformed in the rotational direction about an arbitrary axis included in the plane, whereby the pressure contact surfaces 35 a and 35 b of the vibrator 35 are parallel to the pressure contact surface 34 a of the slider 34. To maintain. Since the leaf spring 38 is not easily deformed in the in-plane direction, the displacement of the vibrator 35 in the optical axis direction (that is, the driving direction) is limited.

Next, a method for fixing the slider 34 to the fourth lens holding member 14 will be described. The fourth lens holding member 14 is formed with a fitting portion 14c into which one end of the slider 34 is fitted and a groove 14d. Reference numerals 40 and 41 denote vibration absorbing members made of butyl rubber, which are thin and concave cap shapes. With this cap shape, the optical axis direction and the optical axis orthogonal direction are positioned. Reference numeral 44 denotes a sheet metal member. Similarly to the first slider unit (18, 26, 27), the vibration absorbing members 40, 41 are covered with the slider 34 to form a second slider unit. At this time, dimensions are set so that the concave portions of the vibration absorbing members 40 and 41 are press-fitted into the slider 34. The vibration absorbing member 40 side of the second slider unit (34, 40, 41) is inserted into the fitting portion 14c of the fourth lens holding member 14. At this time, the vibration absorbing member 41 side of the second slider unit (34, 40, 41) is also inserted into the groove 14d of the fourth lens holding member 14. The entrance of the fitting portion 14d is chamfered so that the second slider unit can be easily inserted.

  Next, the sheet metal member 44 is fitted to the projection 14e of the fourth lens holding member 14. The sheet metal member 44 is formed with a square hole 44a, and this portion (square hole 44a) and the protrusion 14e of the fourth lens holding member 14 are fixed together. The sheet metal member 44 and the vibration absorbing member 41 are dimensioned so as to be charged when assembled. Pressurized and held by the elastic force of the sheet metal member 44 and the vibration absorbing member 41. The fitting portion 14c and the second slider unit (34, 40, 41) are dimensioned so that the side surfaces are press-fitted. From the above, the slider 34 is held without play. Reference numeral 39 denotes a vibrator holding member that holds the vibrator 35 and is fixed to the rear barrel 5 by screws 42 and 43. A plate spring 38 is fixed to the vibrator holding member 39 by screws 46 and 47. Yes.

  Thus, the vibrator 35 is fixed to the rear barrel 5. Reference numeral 48 denotes a scale for detecting the moving amount (position) of the fourth lens holding member 14, and is fixed to the groove portion 14 d formed in the fourth lens holding member 14 by bonding or the like. Reference numeral 49 denotes a light projecting / receiving element that projects light onto the scale 48 and receives reflected light from the scale 48 to detect the amount of movement of the fourth lens holding member 14. The light projecting / receiving element 49 and the scale 48 constitute a second linear encoder as a detector. Reference numeral 50 denotes a flexible wiring board for inputting / outputting signals to / from the light projecting / receiving element 49, and is fixed to the rear barrel 5 by screws 51.

  The second vibration type linear actuator has a guide bar 11, a vibrator 35 and a slider 34. The second linear encoder has a light projecting / receiving element 49 and a scale 48. As shown in FIG. 1, these are the left side surface (light surface), which is another outer plane closest to the optical axis position of the light quantity adjustment unit 15 among the outer peripheral faces of the light quantity adjustment unit 15 as viewed from the front in the optical axis direction. It is arranged close to a straight left long side portion in the axial direction view. The second vibration type linear actuator (11, 34, 35) and the second linear encoder (48, 49) are disposed adjacent to the guide bar 11 so as to sandwich the guide bar 11 in the vertical direction. Yes. A shaft in which the first vibration type linear actuator, the guide bar 10 and the first linear encoder, and the second vibration type linear actuator, the guide bar 11 and the second linear encoder extend in the vertical direction through the center of the optical axis. It is arrange | positioned so that it may become substantially symmetrical.

  A principal block diagram of the optical apparatus (imaging device) in FIG. 12 will be described. Reference numeral 101 denotes an image pickup element constituted by a CCD sensor, a CMOS sensor, and the like. Reference numeral 102 denotes a drive source for the second lens unit 2 (second lens holding member 12), and a first vibration type linear including a slider 18 and a vibrator 19. Actuator. Reference numeral 103 denotes a driving source of the fourth lens unit 4 (fourth lens holding member 14), and a second vibration type linear actuator including a slider 34 and a vibrator 35. Reference numeral 104 denotes a meter as a drive source for the light quantity adjustment unit 15. Reference numeral 105 denotes a second lens encoder as a first linear encoder including the scale 28 and the light projecting / receiving element 29. Reference numeral 106 denotes a fourth lens encoder as a second linear encoder including a scale 48 and a light projecting / receiving element 49. These encoders 105 and 106 respectively detect the relative positions (movement amounts from the reference position) of the second lens unit 2 and the fourth lens unit 4 in the optical axis direction.

  In this embodiment, an optical encoder is used as the encoder. However, a magnetic encoder may be used, or an encoder that detects an absolute position using electrical resistance may be used. Reference numeral 107 denotes an aperture encoder. For example, a diaphragm encoder that detects the rotational positional relationship between the rotor and the stator of the meter 104 by using a hall element provided inside the meter 104 that is a driving source of the light amount adjusting unit 15 is used. . Reference numeral 117 denotes a CPU as a controller that controls the operation of the photographing apparatus. A camera signal processing circuit 108 performs amplification, gamma correction, and the like on the output value from the image sensor 101. The contrast signal of the video signal subjected to these predetermined processes by the camera signal processing circuit 108 passes through the AE gate 109 and the AF gate 110. By these gates 109 and 110, an optimum signal extraction range for determining exposure and focusing is set from within the entire screen.

  These gates 109 and 110 may be variable in size or may be provided in plural. Reference numeral 114 denotes an AF signal processing circuit for autofocus (AF), which extracts a high-frequency component of the video signal from the AF gate 110 and generates an AF evaluation value signal. Reference numeral 115 denotes a zoom switch for performing a zoom operation. Reference numeral 116 denotes a zoom tracking memory which stores target position information for driving the fourth lens unit 4 in accordance with the subject distance and the position of the second lens unit 2 in order to maintain a focused state upon zooming. . Note that the memory in the CPU 117 may be used as the zoom tracking memory.

  In the above configuration, when the photographer operates the zoom switch 115, the CPU 117 controls the first vibration type linear actuator 102 in order to drive the second lens unit 2. At the same time, the optical axis direction of the fourth lens unit 4 based on the information in the first zoom tracking memory 116 and the current position in the optical axis direction of the second lens unit 2 obtained from the detection result of the second lens unit encoder 105. The target drive position is calculated. The second vibration type linear actuator 103 is controlled to drive the fourth lens unit 4 to the target drive position. Whether or not the fourth lens unit 4 has reached the target drive position is the same as the current position in the optical axis direction of the fourth lens unit 4 obtained from the detection result of the fourth lens unit encoder 106 and the target drive position. It is determined depending on whether or not

  In the autofocus, the CPU 117 drives the fourth lens unit 4 so as to search for a position where the AF evaluation value obtained by the AF signal processing circuit 114 exhibits a peak. To control. In order to obtain an appropriate exposure, the CPU 117 controls the light amount so that the average value of the luminance signal that has passed through the AE gate 109 becomes a predetermined value, that is, the output of the aperture encoder 107 becomes a value corresponding to the predetermined value. The meter 104 of the adjusting unit 15 is controlled to control the opening diameter.

  In the above configuration, in order for the first and second vibration type linear actuators to exhibit sufficient performance, it is necessary to suppress unnecessary vibration generated in the sliders 18 and 34. Further, suppressing the vibration of the slider also reduces the noise. In the first vibration type linear actuator (10, 18, 19), both ends of the slider 18 are held with butyl rubber (vibration absorbing members) 26, 27 interposed therebetween, so that generation of unnecessary vibration can be suppressed. . In addition, since a holding fitting portion is formed directly on the rear group barrel 5 and the first lens holding member 6 for fixing the slider 18, no new parts are required for holding. This facilitates the miniaturization and simplification of the lens barrel.

  Also in the second vibration type linear actuator (11, 34, 35), both ends of the slider 34 are held via the butyl rubber (vibration absorbing members) 40, 41 to suppress the occurrence of unnecessary vibration. Can do. In order to fix the slider 34 to the fourth lens holding frame 14, a fitting portion 14 c and a groove 14 d are formed directly on the fourth lens holding frame 14. The slider 34 is held by adding only the sheet metal member 44. The sheet metal member 44 of the added holding part is a simple part with a small occupied volume. Therefore, the slider 34 can be easily held in a very small size. Further, the slider 18 is configured using a magnet, and obtains a pressure contact force necessary for generating a driving force as a vibration type linear actuator by attracting the vibrator 19. For this reason, the reaction force of the pressure contact force does not act on the second lens holding member 12.

  Thereby, the frictional force generated in the engaging portions 12a and 12b engaged with the guide bars 10 and 11 for guiding the second lens holding member 12 does not increase, and the driving load due to friction does not increase. Moreover, since the force generated by the leaf spring 22 is small, the force acting on the engaging portions 12a and 12b engaged with the guide bars 10 and 11 from the leaf spring 22 is also small, and the friction generated on the engaging portions 12a and 12b. Little increase in power. Therefore, it is possible to use a low-power and small vibration type linear actuator. As a result, the lens barrel can be downsized. In addition, since a large pressure contact force does not act on the second lens holding member 12, the frictional force generated in the engaging portions 12 a and 12 b that engage with the guide bars 10 and 11 that guide the second lens holding member 12 is generated. Does not grow.

  Therefore, it is not necessary to increase the output or size of the first vibration type linear actuator 102, and it is possible to reduce wear due to friction with the guide bars 10 and 11 engaged with the engaging portions 12a and 12b. Further, the minute driving of the second lens holding member 12 (second lens unit 2) can be performed accurately. Further, it is assumed that the position of one of the pressure contact surfaces with respect to the axis parallel to the optical axis or the inclination around the axis changes in the optical axis direction due to a manufacturing error or the like. Even in this case, when the leaf spring 22 is deformed and the position and the inclination (orientation) of the vibrator 19 are changed, the two pressure contact surfaces are maintained in parallel and an appropriate surface contact state is maintained.

  Further, the spring constant is set so that the leaf spring 22 is deformed with a force smaller than the pressure contact force. For this reason, even when the position and inclination of the pressure contact surface change, the pressure contact force does not change greatly. Therefore, it is possible to stably extract an output corresponding to the inherent performance of the first vibration type linear actuator 102. Further, when a strong impact force due to dropping or the like is applied to the lens barrel, a strong force is applied to the guide bars 10 and 11 due to the mass of the second lens holding frame 12 and the fourth lens holding frame 14, and the guide bars 10 and 11. Elastic deformation occurs. Due to the elastic deformation of the guide bars 10, 11, the second lens holding frame 12 and the fourth lens holding frame 14 are instantaneously displaced, and the clearance between the components changes.

  Even when the second lens holding member 12 is displaced toward the pressure contact surface 18 a of the slider 18, the leaf spring 22 is deformed to absorb the impact. Since the spring force due to the deformation of the leaf spring 22 is sufficiently small, a large force is not applied to the vibrator 19 and damage or the like can be prevented. When the displacement of the second lens holding member 12 reaches L2, the stoppers 12e and 12f come into contact with the rear barrel 5 and the first lens holding member 6. Therefore, the maximum displacement amount of the second lens holding member 12 is determined by L2. The amount by which the leaf spring 22 can be displaced is determined by L1. Since L1> L2, even when a strong impact force is applied to the lens barrel, the displacement amount of the lens holding member 12 is within the displacement range of the leaf spring 22, and the strong impact force is a vibration type linear. It is not transmitted to the actuator.

  Thereby, damage to the vibration type linear actuator can be prevented. In addition, by providing the stoppers 12e and 12f with appropriate dimensions as described above, it is not necessary to increase the gap L1 between the spacer 21 and the second lens holding member 12 as a countermeasure against impacts. A linear actuator can be arranged. Even when the fourth lens holding member 14 is displaced in the direction of the pressure contact surfaces 35a and 35b of the vibrator 35, the leaf spring 38 is deformed to absorb the impact. Since the spring force due to the deformation of the leaf spring 38 is sufficiently small, a large force is not applied to the vibrator 35 and the slider 34, and damage can be prevented.

  On the other hand, the slider 34 is configured by using a magnet, and obtains a pressure contact force necessary for generating a driving force as a vibration type linear actuator by attracting the vibrator 35. For this reason, the reaction force of the pressure contact force does not act on the fourth lens holding member 14. Thereby, the frictional force generated in the engaging portions 14a and 14b engaged with the guide bars 11 and 10 that guide the fourth lens holding member 14 does not increase, and the driving load due to friction does not increase. In addition, since the force generated by the leaf springs 33 and 38 is small, the force acting on the engaging portions 14a and 14b with the guide bars 11 and 10 from the leaf springs 33 and 38 is also small and generated at the engaging portions 14a and 14b. The frictional force to increase is hardly increased.

  Therefore, it is possible to use a low-power and small vibration type linear actuator. As a result, the lens barrel can be downsized. In addition, since a large pressure contact force does not act on the fourth lens holding member 14, the frictional force generated in the engaging portions 14 a and 14 b that engage with the guide bars 11 and 10 that guide the fourth lens holding member 14 is generated. Does not grow. Therefore, it is not necessary to increase the output or size of the second vibration type linear actuator 103, and it is possible to reduce wear due to friction with the guide bars 11 and 10 engaged with the engaging portions 14a and 14b. Further, the minute driving of the fourth lens holding member 14 (fourth lens unit 4) can be performed accurately.

  It is assumed that the position of one of the pressure contact surfaces with respect to the axis parallel to the optical axis or the inclination around the axis changes in the optical axis direction due to a manufacturing error or the like. In this case, the leaf springs 33 and 38 are deformed to change the position and inclination (orientation) of the vibrator 34, so that the two pressure contact surfaces are maintained in parallel and an appropriate surface contact state is maintained. The spring constants are set so that the leaf springs 33 and 38 are deformed with a force smaller than the pressure contact force. For this reason, even when the position and inclination of the pressure contact surface change, the pressure contact force does not change greatly. Therefore, the output according to the performance inherent to the second vibration type linear actuator 103 can be stably extracted.

  As described above, in this embodiment, the guide bar 10, the first vibration type linear actuator (18, 19), and the first linear encoder (28, 29) in the optical axis direction view are as follows. It has become. In other words, the light amount adjustment unit 15 is arranged along (to be close to) the right side which is one of the planes closest to the optical axis. The first vibration type linear actuator (18, 19) and the first linear encoder (28, 29) are arranged adjacent to the upper and lower sides of the guide bar 10. Further, the guide bar 11, the second vibration type linear actuator (34, 35), and the second linear encoder (48, 49) are as follows in the optical axis direction view.

  It arrange | positions so that the left side surface which is one of the planes nearest to the optical axis among the light quantity adjustment units 15 may be met (close). The second vibration type linear actuator (34, 35) and the second linear encoder (48, 49) are arranged adjacent to the upper and lower sides of the guide bar 11. The lens barrel includes a light amount adjusting unit 15 and two vibration linear actuators (102, 102) that respectively drive the second and fourth lens holding members 12 and 14 disposed on the object side and the image plane side of the light amount adjusting unit 15. 103). Furthermore, it has two guide bars 10, 11 for guiding the lens holding members 12, 14 in the optical axis direction, and two linear encoders (105, 106) for detecting the positions of the lens holding members 12, 14, respectively. ing.

  By configuring these as described above, the size can be reduced. Further, since the sliders 18 and 34 are disposed adjacent to the guide bars 10 and 11, the second and fourth lens holding members 12 and 14 can be driven smoothly. Scales 28 and 48 constituting first and second encoders are disposed adjacent to the guide bars 10 and 11. Thereby, the displacement of the scales 28 and 48 due to the backlash of the engaging portions 12a, 12b, 14a and 14b to the guide bars 10 and 11 in the second and fourth lens holding members 12 and 14 is small, and the position detection is performed with high accuracy. It can be carried out.

  It is assumed that the linear actuator and the linear encoder are arranged on the opposite side of the optical axis with respect to the guide bar that guides the lens holding member that is the driving target and the position detection target. In this case, the engagement of the engaging portion of the lens holding member with the guide bar may cause the linear encoder to be displaced in the direction opposite to the driving direction with the guide bar as a fulcrum at the start of driving. This causes the position detection accuracy to deteriorate. However, in this embodiment, since the linear actuator and the linear encoder are arranged on the same side as the guide bar that guides the lens holding member that is the driving target and the position detection target, such a problem does not occur and the accuracy is high. The position can be detected well.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to the configurations described in these embodiments, and various modifications and changes can be made to the above-described embodiments.
In the above-described embodiment, the case where magnetic force is used for pressurizing the vibration type linear actuator has been described. However, the present invention uses a pressurizing mechanism such as an elastic member for pressing the vibration type linear actuator. It can also be applied to. Furthermore, in the above-described embodiments, the lens-integrated photographing apparatus has been described. However, the present invention can also be applied to an interchangeable lens (optical apparatus) that can be attached to and detached from the photographing apparatus body. Further, the present invention can be applied not only to the photographing apparatus but also to various optical devices that drive a lens by a vibration type linear actuator.

DESCRIPTION OF SYMBOLS 1 1st lens unit, 2nd 2nd lens unit, 3rd 3rd lens unit, 4,204 4th lens unit, 5 rear part barrel, 6 1st lens holding member 10, 11, 11 guide bar, 12 2nd lens holding member , 14 Fourth lens holding member, 15 Light quantity adjustment unit, 18, 34 Slider, 19, 35 Vibrator, 22, 38 Leaf spring, 26, 27, 40, 41 Vibration absorbing member, 28, 48 Scale, 29, 49 Throw Light receiving element, 44, sheet metal, 101 imaging element

Claims (5)

An optical element holding member that holds and moves the optical element, a guide means for guiding the movement of the optical element holding member, a base member that holds the guide means, a vibrating member that vibrates, and a contact with the vibrating member And a vibration type linear actuator constituted by a contact member that
The contact member has vibration absorbing members attached to both ends in the moving direction, and is fixed to the base member or the optical element holding member via the vibration absorbing member ,
The vibration absorbing member is configured to position the contact member in an optical axis direction of the optical element and a direction orthogonal to the optical axis, and is attached so as to cover an end of the contact member. ,
A lens barrel characterized by that. A sheet metal member provided between the vibration absorbing member and the optical element holding member;
The lens barrel according to claim 1 , wherein the sheet metal member is configured to press the vibration absorbing member against the contact member .   The base member has a first base member and a second base member, the first base member has a concave first fitting portion, and the second base member has a concave second shape. The contact member has a fitting portion, and the contact member is fixed by fitting one end with the first fitting portion and the other end with the second fitting portion via the vibration absorbing member. The lens barrel according to claim 1 or 2, wherein The direction in which the optical element holding member moves the lens barrel according to claim 1 to 3 any one, characterized in that an optical axis direction or the direction perpendicular to the optical axis of the optical element.   An optical apparatus comprising the lens barrel according to any one of claims 1 to 4.