JP2010191070A - Lens barrel and optical device including with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a lens barrel having impact resistance which performs optical adjustment, by the tilting of a specific lens holding frame in the barrel body and decentering of an optical axis, and thereafter, stably keeps the adjusted state over a long period. <P>SOLUTION: The lens barrel includes a lens-holding members holding lenses; the cylindrical barrel body; and a lens-adjusting mechanism of adjusting the position of the lens-holding member toward the inner peripheral side of the barrel body. A plurality of through-holes are formed in the outer peripheral surface of the barrel body, and pin members are attached on the outer peripheral surface of the lens-holding member through the through-holes; and the lens-holding member is secured to the barrel body with adhesive filled around the pin members from the through-holes. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lens barrel and an optical apparatus having the lens barrel, and is suitable for an optical apparatus such as a digital camera or a video camera that can stably fix and hold a lens holding member that holds a lens inside the barrel main body. Is.

  In a lens barrel used in an optical device such as a digital camera or a video camera, when a lens holding member for holding each lens group is incorporated in the lens barrel body, the inclination of the lens group or the optical axis is decentered. Assembled with optical adjustment. When a lens group is optically adjusted and incorporated into a lens barrel body, a lens barrel is known in which a lens holding member is fixed using an adhesive so that no deviation occurs after adjustment (Patent Document 1).

  In Patent Literature 1, when the inclination of the second lens holding frame is adjusted with respect to the first lens holding frame and both are fixed, the adjustment position is held by an adjusting jig. A plurality of radial through holes are provided in the second lens holding frame, and adhesive fixing is performed with an adhesive that flows between the first lens holding frame and a recess (stop hole) provided at a position facing the through hole. is doing. In addition, as another method of optical adjustment of the lens holding frame, there is a method of fixing after adjusting the lens holding frame for adjustment with respect to a fixing member such as a fixing cylinder using an eccentric pin or an eccentric roller. Are known. In this method, a lens holding frame holding an adjustment lens is arranged inside the fixed cylinder, and eccentric rollers such as eccentric rollers are respectively inserted into three through holes provided at three equal positions in the circumferential direction of the fixed cylinder. The core member is inserted. The eccentric roller is fixed to the lens holding frame with a screw to fix both. In the optical adjustment method, a screw for fixing the eccentric roller is temporarily fixed, the eccentric roller is rotated, and the lens holding frame is adjusted to a desired tilt amount with respect to the fixed cylinder, and then finally tightened with a screw. It is carried out.

JP 2002-006190 A

  The objective lens unit of Patent Document 1 uses a method in which an adhesive is poured between a through hole and a recess (blind hole), and both are adjusted and bonded and fixed, and the adjustment position is maintained only by the strength of the adhesive. To do. For this reason, when the adhesive is peeled, deformed, or chipped, the adjustment position may be shifted. In addition, when an impact in the optical axis direction is applied to the lens frame, a force acts in a direction in which the adhesive tends to come out in the outer diameter direction, in which case the adhesive easily peels off from the lens barrel, and the adjustment position changes. It may end up. Also, in the adjustment structure for the lens barrel of the lens holding frame using the eccentric roller for adjustment, the adjusted state of the eccentric roller after adjustment is held only by the fastening force of the screw for fixing the eccentric roller. For this reason, when a strong external force is applied, the eccentric roller may rotate, and the adjustment state of the lens holding frame may change. Therefore, in any method for adjusting the lens holding frame, there has been a problem that the optical performance deteriorates due to the lens holding frame being displaced from the adjusted position of the lens barrel body by an external force in a long-term use.

  The present invention provides an impact-resistant lens that can stably hold the state of adjustment for a long period of time after optical adjustment by tilting or decentering the lens holding body of a specific lens holding frame. An object of the present invention is to provide a lens barrel and an optical apparatus having the same.

  The lens barrel of the present invention includes a lens holding member that holds a lens, a cylindrical barrel main body, and a lens adjustment mechanism that adjusts the position of the lens holding member on the inner peripheral side of the barrel main body. A plurality of through holes are provided on the outer peripheral surface of the lens barrel main body, and a pin member is attached to the outer peripheral surface of the lens holding member from the through holes, and the lens holding member is The lens barrel main body is fixed by an adhesive filled around the pin member from the plurality of through holes.

  According to the present invention, after performing optical adjustment by tilting or decentering the lens holding body of a specific lens holding frame, the state at the time of adjustment can be stably maintained over a long period of time. A lens barrel is obtained.

1 is a main cross-sectional view of a lens barrel according to an embodiment of the present invention. 1 is an exploded perspective view of a lens holding frame and a straight guide cylinder according to an embodiment of the present invention. 1 is an exploded perspective view around a lens holding frame according to an embodiment of the present invention. Detailed view of adjusting member (eccentric roller) according to an embodiment of the present invention Sectional drawing which shows the fixed state after optical adjustment of the lens barrel which concerns on embodiment of this invention The perspective view which shows the fixed state after optical adjustment of a part of lens barrel which concerns on embodiment of this invention

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The lens barrel of the present invention will be described below with reference numerals of members described later. When holding the lens holding member (first group barrel 15) holding the first lens L1, the cylindrical barrel body (straight guide tube) 13, and the lens holding member on the inner peripheral side of the barrel body, And a lens adjusting mechanism including an eccentric roller for adjusting both positions. A plurality of through holes (through holes 13e) are provided on the outer peripheral surface of the barrel main body 13 to reinforce both of the lens holding member when the lens holding member is fixedly held on the barrel main body. A pin member (reinforcing screw 25) having a diameter smaller than that of the through hole 13e provided in the lens barrel body 13 is attached to the outer peripheral surface of the lens holding member 15. The lens holding member 15 is fixed to the lens barrel main body 13 through a plurality of through holes 13 e with a pin member 25 and with an adhesive filled around the pin member 25. The first group lens barrel 15 is positioned and adjusted with respect to the rectilinear guide tube 13 in the plane orthogonal to the optical axis of the first lens L 1 by the rotation of the eccentric roller 22. At this time, the inclination with respect to the optical axis of the first group barrel 15 is adjusted by the displacement (distance ± X) of the first group barrel 15 in the optical axis direction due to the rotation of the eccentric roller 22. In addition, the position of the optical axis of the lens held in the first group barrel 15 is adjusted with respect to the axis of the rectilinear guide barrel 13 by displacement in a plane orthogonal to the optical axis of the first group barrel 15. .

[Example]
FIG. 1 is a schematic view of a main part of an embodiment in which the lens barrel of the present invention is applied to an interchangeable lens barrel of a single-lens reflex camera (optical apparatus). FIG. 2 is an exploded perspective view of the vicinity of a part of the first group barrel 15 and the straight guide barrel 13 in FIG. FIG. 3 is a perspective view of an essential part of the first group lens barrel 15 in a part of FIG. 4 is a cross-sectional view of the main part of the eccentric roller 22 of FIG. FIG. 5 is a cross-sectional view of a main part after optical adjustment of the lens barrel of the present invention. FIG. 6 is a schematic external view of a part of a lens barrel of the present invention.

  In the present embodiment, a fixed cylinder 12 is fixed to a detachable mount 11 with respect to the camera body CB. A linear guide cylinder (lens barrel main body) 13 is fixed to the fixed cylinder 12. A first group lens barrel (lens holding member) 15 that holds a lens (first group) L1 is fixed to the rectilinear guide tube 13. These members 12 and 13 are fixing members for the interchangeable lens barrel. A rectilinear guide groove 13a parallel to the optical axis direction is formed in the rectilinear guide tube 13. The rectilinear guide groove 13 a is used as a rectilinear guide in the optical axis direction of the second group barrel 16 and the third group barrel 17. On the second group barrel 16 holding the lens (second group) L2, rollers 18 protruding outward in the radial direction are fixed by shaft screws 19 (three places equal in the circumferential direction). The straight guide groove 13a is fitted. A roller 20 projecting radially outward is fixed to the third group lens barrel 17 holding the focusing lens (third group) L3 by shaft screws 21 (three places in the circumferential direction). 20 are fitted in the rectilinear guide grooves 13a of the rectilinear guide tube 13, respectively.

  A cam ring 14 is rotatably fitted on the outer periphery of the rectilinear guide tube 13. In the rectilinear guide tube 13 and the cam ring 14, three bayonet claws 13 b provided at equal positions in the outer peripheral direction of the rectilinear guide tube 13 are fitted in the circumferential groove 14 a of the cam ring 14. Thereby, the relative movement in both optical axis directions is restricted, and the cam ring 14 can freely rotate with respect to the rectilinear guide tube 13. The cam ring 14 is formed with cam grooves 14b and 14c for driving the second group barrel 16 and the third group barrel 17, and the aforementioned roller 18 is fitted into the cam groove 14b, and the cam groove 14c is fitted into the cam groove 14c. Is fitted with the roller 20 described above. The lens L1 is held by a first group barrel (lens holding member) 15. The first lens barrel 15 projecting to the outer diameter of the first lens barrel 15 is rotated on at least three positions on the seating surface (roller seating surface) 15i of the first lens barrel 15 in order to adjust the position of the first lens barrel 15 to the rectilinear guide tube 13. A possible eccentric roller (adjusting member) 22 is fixed by a shaft screw 23 after position adjustment. At this time, the eccentric rollers 22 are provided at three locations evenly in the circumferential direction. The eccentric roller 22 is fitted into an elliptical groove 13 c provided at the tip of the linear guide tube 13 and having a long side in the circumferential direction.

  As described above, the first group lens barrel 15 is configured such that the optical axis direction is positioned with respect to the rectilinear guide tube 13 by the eccentric roller 22. That is, by rotating the eccentric roller 22, the first group lens barrel 15 can be adjusted with respect to the rectilinear guide tube 13 in the tilting direction with respect to the optical axis (lens tilt adjustment). The fitting projection 15f of the first group barrel 15 is in contact with the inner diameter portion 13g of the rectilinear guide tube 13, and the position is determined in the radial direction (in the plane orthogonal to the optical axis). As described above, the first group barrel 15 is positioned with respect to the linear guide barrel 13 in both the radial direction and the optical axis direction.

  The configuration of the eccentric roller 22 as the adjustment member will be described with reference to FIG. The eccentric roller 22 includes a cylindrical portion 22a coaxial with the screw through hole 22d, and a cylindrical portion 22b whose center is eccentric at a position shifted by a distance X from the cylindrical portion 22a. The eccentric roller 22 is configured such that the cylindrical portion 22a of the eccentric roller 22 is fitted to the roller fitting portion 15j of the first group lens barrel 15, and is fixed to the roller seating surface 15i of the first group lens barrel 15 with screws 23. By fitting a tool into the slit portion 22c of the eccentric roller 22 and rotating the eccentric roller 22, the position of the first group lens barrel 15 in the optical axis direction can be finely adjusted by ± X.

  As shown in FIG. 2, a wave washer (spring member) 24 is disposed between the stepped surface 15 b of the first group barrel 15 and the front end surface 13 d of the rectilinear guide tube 13. The wave washer 24 generates a force in a direction in which the first group barrel 15 and the rectilinear guide tube 13 are separated from each other in the assembled state. That is, it is energized. Therefore, the biasing force of the wave washer 24 always keeps the eccentric roller 22 and the front side surface 13f of the elliptical groove 13c of the linear guide tube 13 in close contact with each other.

  Thus, the first group barrel 15 and the rectilinear guide tube 13 are biased by the spring member (washer 24) in the direction away from the optical axis. Due to this urging force, the plurality of eccentric rollers 22 fixed to the first group barrel 15 are brought into close contact with the surface 13f in the hole 13c of the straight guide tube 13, and the optical axis direction of the straight guide tube 13 and the first group barrel 15 is fixed. Is stuffed.

  The shape of the first group barrel 15 will be described with reference to FIG. The first group lens barrel 15 is formed with a recess 15j into which the first peripheral surface 22a1 of the cylindrical portion 22a of the eccentric roller 22 is fitted, and an adhesive reservoir 15c provided around the recess 15j. Further, a screw hole 15d into which the reinforcing screw (pin member) 25 is screwed, and an adhesive reservoir 15e for fixing the reinforcing screw 25 are formed so as to surround the periphery. Furthermore, a press-fitting protrusion 15f and an adhesive flow prevention protrusion 15h that are press-fitted into the inner peripheral surface 13g of the linear guide cylinder 13 are provided.

  The procedure for incorporating the first group barrel 15 into the straight guide cylinder 13 will be described with reference to FIG. First, the wave washer 24 is inserted into the first group barrel 15 up to the vicinity of the stepped surface 15b. Next, the inner peripheral surface 13g of the rectilinear guide tube 13 is diameter-fitted to the first group barrel 15 (because of the press-fitting projection 15f, the press-fitting state is established), and the wave washer 24 is placed between the stepped surface 15b and the front end surface 13d. Push it all the way in while charging it. When the concave groove 15j of the first group lens barrel 15 can be seen from the elliptical groove (circumferential groove) 13c of the rectilinear guide tube 13, the eccentric roller 22 is inserted through the elliptical groove 13c, and the eccentric roller 22 is inserted into the first group lens barrel. It fixes to the roller seating surface 15i of the 15 recessed parts 15j with the screw | thread 23. FIG. As shown in FIG. 4, in the eccentric roller 22, the second peripheral surface 22b of the cylindrical portion 22b is eccentric by the eccentric amount X with respect to the first peripheral surface 22a. A slot 22c is provided in the eccentric direction. Here, the eccentric roller 22, the elliptical groove 13 c, the recess 15 j, etc. constitute a part of a lens adjustment mechanism for adjusting the position of the first group barrel 15 to the rectilinear guide barrel 13. The above-described portions of the first group barrel 15 have the same shape at three portions different in phase by 120 °, and the first group barrel 15 is fixed to the rectilinear guide tube 13 using three eccentric rollers 22. . At this stage, the eccentric roller 22 is assembled so that the slot 22c is oriented in the circumferential direction of the first lens barrel 15 (that is, the tilt adjustment amount is zero), and the screw 23 is lightly tightened. . Thereafter, a reinforcing screw (pin member) 25 is screwed into the screw hole 15d of the first group barrel 15 which can be viewed from the rectangular or substantially rectangular through hole 13e of the linear guide tube 13. The screw 25 of the reinforcing screw 25 has a small diameter with respect to the screw head. The length under the screw neck of the reinforcing screw 25 is longer than the screw hole depth of the screw hole 15d of the first group barrel 15. For this reason, the reinforcing screw 25 stops when the screw tip abuts against the hole bottom of the screw hole 15d, and the screw head is in a state where the head floats with respect to the mounting surface.

  Next, a method for fixing the adjustment position after optical adjustment of the lens barrel of the present invention will be described with reference to FIGS. First, while confirming the projection state of the assembled lens barrel, an arbitrary portion of the three eccentric rollers 22 is rotated, and the first group lens barrel is shifted in the optical axis direction so as to be in a desired optical adjustment state. Thus, the inclination (lens inclination) of the first group lens barrel 15 with respect to the straight guide cylinder 13 is adjusted. Specifically, when an eccentric roller having an arbitrary phase among the three eccentric rollers is rotated (since the eccentric roller housed in the elliptical groove 13c is eccentric by X), the first group mirror Only the portion corresponding to the phase of the eccentric roller rotated by the cylinder 15 is displaced by ± X in the optical axis direction. At this time, the portion corresponding to the phase of the remaining eccentric roller that is not rotated in the first group barrel 15 does not move in the optical axis direction. Can be adjusted by tilting in the direction.

  In addition, when the movement of the first group lens barrel 15 in the optical axis direction with respect to the rectilinear guide tube 13 is restricted and the relative rotation is possible, the eccentric roller 22 is used, and the following adjustment is also possible. It becomes possible. The longitudinal direction of the ellipse of the elliptical groove 13c is set to the optical axis direction, the eccentric roller 22 is rotated, and the first group lens barrel 15 is displaced in a plane orthogonal to the optical axis, thereby the first group lens barrel (the optical axis of the lens). The fixing method of the present invention can also be applied when the position is adjusted with respect to the axis of the straight guide tube 13. When the adjustment position of the eccentric roller 22 is determined, the eccentric roller fixing screws 23, which have been temporarily fixed, are finally tightened at all three locations to firmly fix the eccentric roller 22 to the first group lens barrel 15.

  Next, an adhesive 26 such as a UV curable adhesive is filled around the reinforcing screw 25 from the gap 13h on both sides of the eccentric roller 22 in the elliptical groove 13c of the rectilinear guide tube 13 and the through hole 13e. Then, it is cured by irradiating with ultraviolet rays (same for all three phases). As a result, the first group lens barrel 15 is fixed to the rectilinear guide tube 13. Thus, the adhesive filled in the gap between the elliptical groove 13 c of the linear guide cylinder 13 and the eccentric roller 22 exhibits an adhesive force between the elliptical groove 13 c and the eccentric roller 22. Furthermore, even if the interface between the elliptical groove 13c and the adhesive or the interface between the eccentric roller 22 and the adhesive is peeled off due to a strong impact, the eccentric roller will remain as long as the adhesive remains in place. It can prevent that 22 rotates easily from an adjustment position. The adhesive filled around the reinforcing screw 25 from the through hole 13e is hardened in the same shape as the through hole 13e, so that a large area is received when a strong impact in the optical axis direction is applied to the lens barrel. be able to.

  With the above configuration, when an impact is applied to the lens barrel, the load is received only by the eccentric roller 22, and the eccentric roller 22 and the adhesive solidified in a square shape filled in the through hole 13e are used. Will receive a load. For this reason, even when an external force is applied, it becomes difficult for the eccentric roller 22 to be deformed such as rotating or crushing. Therefore, the shift of the adjustment position can be reduced. Therefore, even after optical adjustment of the first group barrel to the straight guide barrel, the initial adjustment state can be maintained with a high probability over a long period of time, and a robust lens barrel can be achieved.

  According to the lens barrel of the present embodiment, the lens barrel that can suppress the possibility that the optical adjustment state is changed due to some spring after the optical adjustment and can maintain the optical adjustment state at the time of assembly for a long period of time. Is obtained.

  In addition, in this embodiment, the following effects can be obtained by applying the reinforcing screw 25 in addition to the eccentric roller 22. By inserting the reinforcing screw 25, the adhesive sandwiched between the circumferential groove wall surface of the linear guide tube 13 and the reinforcing screw 25 receives a compressive load when receiving an impact. Therefore, even if the adhesive is weak against the force in the shear direction, it can be used if it is an adhesive having a strong compressive load, and the selection range of the adhesive is expanded. Further, when an impact load is applied, a moment in a direction in which the adhesive tends to come out to the outer diameter side of the straight guide tube 13 is applied. At this time, since the screw head portion of the reinforcing screw 25 has an effect of preventing the adhesive from coming off in the outer diameter direction, the fixing structure has higher strength against impact. Moreover, compared with the case where the reinforcing screw 25 is not provided, a strong wedge effect is exhibited for the same adhesive volume. If the adhesive is not applied to the screw head of the reinforcing screw 22 when filling the adhesive, the reinforcing screw 22 can be easily removed using a screwdriver when dismantling, and the remaining adhesive The work of removing the agent is also facilitated.

  Although the said Example demonstrated the UV hardening type adhesive agent as an example as a solid for reinforcement, it does not necessarily need to be an adhesive agent, and it can apply similarly, if the hardness at the time of hardening is high. In the above embodiment, the through hole 13c of the rectilinear guide tube 13 has a quadrangular shape, but it may be any polygonal shape, and even if the strength is somewhat reduced, it is effective even if it is circular, and is not limited to a quadrangular shape. Absent. For example, when the direction of the elongated hole of the circumferential groove 13 c is deformed from the circumferential direction to the optical axis direction, the optical axis of the first group barrel 15 can be shifted with respect to the central axis of the rectilinear guide barrel 13. The above embodiments can be applied to various lens barrels regardless of the type of camera, such as interchangeable lens barrels of single-lens reflex cameras, compact cameras, and electronic still cameras.

  L1 ... 1 group lens, L2 ... 2 group lens, L3 ... 3 group lens (focus lens), 12 ... fixed tube, 13 ... straight guide tube, 14 ... cam ring, 15 ... 1 group lens holding frame, 16 ... 2 group Lens holding frame, 17 ... 3 group lens holding frame, 22 ... Adjustment member (eccentric roller), 23 ... Screw, 25 ... Fixing pin

Claims (7)

  A lens barrel having a lens holding member for holding a lens, a cylindrical barrel main body, and a lens adjustment mechanism for adjusting the position of the lens holding member on the inner peripheral side of the barrel main body. A plurality of through holes are provided in the outer peripheral surface of the main body, a pin member is attached to the outer peripheral surface of the lens holding member from the through hole, and the lens holding member is attached to the lens barrel main body with the plurality of through holes. A lens barrel characterized by being fixed with an adhesive filled around the pin member from a through hole.   The pin member is made of a screw that is attached to a screw hole of the lens holding member, and the screw has a small diameter with respect to the screw head, and the screw neck length is the depth of the screw hole of the lens holding member. The lens barrel according to claim 1, wherein the lens barrel is longer than the length.   The lens barrel according to claim 1 or 2, wherein the lens holding member is provided with an adhesive reservoir so as to surround a periphery of a screw hole for fixing the pin member.   The lens adjustment mechanism has a plurality of adjustment members rotatably attached to at least three locations on the outer peripheral surface of the lens holding member, and in a plane orthogonal to the optical axis of the lens by the rotation of the adjustment member. The lens holding member is positioned and adjusted with respect to the lens barrel body, and the tilt of the lens holding member with respect to the optical axis is adjusted by the displacement of the lens holding member in the optical axis direction due to the rotation of the adjustment member. The lens barrel according to claim 1, 2 or 3.   The lens adjustment mechanism has a plurality of adjustment members rotatably attached to at least three positions on the outer peripheral surface of the lens holding member, and a surface orthogonal to the optical axis of the lens by the rotation of the adjustment member. The lens holding member is positioned and adjusted with respect to the lens barrel body, and is held by the lens holding member by displacement in a plane perpendicular to the optical axis of the lens holding member due to rotation of the adjustment member. 4. The lens barrel according to claim 1, wherein the optical axis of the lens is adjusted with respect to the axis of the barrel main body.   The lens holding member and the lens barrel body are biased in a direction away from each other in the optical axis direction by a spring member, and the plurality of adjustment members fixed to the lens holding member are in close contact with the lens barrel body, The lens barrel according to claim 4, wherein a gap between the lens barrel main body and the lens holding member is filled.   An optical apparatus comprising the lens barrel according to claim 1.