JP2018077374A - Lens barrel and optical instrument including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical instrument that can suppress deformation of an optical surface of a plastic mold lens and stably hold the position for optical adjustment.SOLUTION: A lens barrel comprises: a lens holding frame that regulates the position of an optical axis orthogonal direction of a plastic mold lens; an outer cylinder arranged at a side of an outer diameter of the lens holding frame and adjustably holding the lens holding frame in a direction inclined from the optical axis orthogonal direction or the optical axis; and a lens pressing plate generating a biasing force to the plastic mold lens between the lens holding frame and the lens pressing plate in the optical axis direction. The biasing force holds the plastic mold lens to be sandwiched between the lens holding frame and the lens pressing plate to contact and fix the lens pressing plate to the lens holding frame. The biasing force is generated by deformation of at least one cantilever beam provided on one of the lens pressing plate and the lens holding frame and extending around the optical axis.SELECTED DRAWING: Figure 1

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 and a video camera that can stably fix a lens to a lens holding frame.

  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 in a lens barrel body, a lens barrel is known in which a lens holding frame is fixed using an adhesive so that no deviation occurs after adjustment (Patent Document 1).

  In patent document 1, it has the 2nd lens barrel arrange | positioned between the 1st lens barrel member and the 3rd lens barrel member, and is adjusted to an optical axis orthogonal direction. The second lens barrel is adjusted in the direction perpendicular to the optical axis, and then adhered and fixed to one of the first and third lens barrel members. In addition, it has an elastic portion that is integrally formed with one of the second lens barrel member or the third lens barrel member and biases the second lens barrel member in the optical axis direction. Since the second lens barrel is urged in the optical axis direction by the elastic portion, stable adjustment can be performed when adjusting in the direction orthogonal to the optical axis, so that adjustment can be performed with high accuracy.

JP, 2006-511175, A

  By the way, in recent years, a plastic mold lens, not a glass lens, is often used as a lens for a digital camera lens or a video camera lens from the viewpoint of weight reduction and cost merit. Even in a lens group using a plastic mold lens, optical adjustment may be performed to decenter the lens group or decenter the optical axis. It is difficult for plastic mold lenses to employ caulking, which is a means for fixing a conventional glass lens to a lens holding frame, or a presser ring by screwing.

  This is because the plastic mold lens is soft with respect to the glass lens, and the press ring by caulking or screwing deforms the optically effective surface through which the light incident on the lens barrel of the plastic mold lens passes. Therefore, optical adjustment of a lens group using a plastic mold lens is often performed by adhering and fixing the plastic mold lens itself to the lens holding frame after adjusting the position of the plastic mold lens with respect to the lens holding frame.

  However, some plastic mold lenses have low hydrophilicity, and the conventional adhesive fixing causes the adhesion to be peeled off at high or low temperatures, causing the plastic mold lens to shift from the adjustment position and degrade optical performance. was there.

  An object of the present invention is to provide an optical apparatus that can suppress deformation of an optical surface of a plastic mold lens and can stably hold a position during optical adjustment.

  To achieve the above object, the present invention provides a lens holding frame that regulates the position of a plastic mold lens in the direction orthogonal to the optical axis, and the lens holding frame that is disposed on the outer diameter side of the lens holding frame. Alternatively, an outer cylinder that can be adjusted in a direction inclined with respect to the optical axis, and a lens pressing plate that generates a biasing force in the optical axis direction between the plastic mold lens and the lens holding frame, With the urging force, the plastic mold lens is sandwiched between the lens holding frame and the lens pressing plate, the lens pressing plate is bonded and fixed to the lens holding frame, and the urging force is applied to the lens pressing plate or the lens. It is formed by deformation of at least one cantilever beam provided on one of the holding frames and extending in the direction around the optical axis.

  ADVANTAGE OF THE INVENTION According to this invention, the optical device which can suppress the deformation | transformation of the optical surface of a plastic mold lens and can hold | maintain the position at the time of optical adjustment stably is obtained.

1 is an exploded perspective view of a lens holding frame unit according to an embodiment of the present invention. 1 is a main cross-sectional view of a lens barrel according to an embodiment of the present invention. The perspective view of the state in which the lens holding frame unit which concerns on embodiment of this invention was integrated in the outer cylinder 1 is an exploded perspective view of a lens holding frame unit and an outer cylinder according to an embodiment of the present invention. The perspective view of the lens holding frame unit which concerns on embodiment of this invention The side view of the lens holding frame unit which concerns on embodiment of this invention The side view at the time of the lens holding ring incorporation according to the embodiment of the present invention 1 is an exploded perspective view of a lens holding frame unit according to an embodiment of the present invention. The front view of the lens holding frame which concerns on embodiment of this invention The perspective view of the lens holding plate which concerns on embodiment of this invention Sectional drawing of the lens holding frame unit which concerns on embodiment of this invention

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Embodiment 1]
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 2 is a schematic cross-sectional view of an example in which the lens barrel of the present embodiment is applied to an interchangeable lens barrel of a single-lens reflex camera (an optical device having an image sensor on which a subject image is formed).

  In the present embodiment, the connection between the camera body 1 and the lens barrel 2 is made via a detachable mount 18. A fixed cylinder 28 is fixed to the detachable mount via the eighth lens L8 and the outer ring 17. The substrate unit 21 is sandwiched between the outer ring 17 and the fixed cylinder 28. An MF ring 24 is sandwiched between the fixed cylinder 28 by an MF ring presser ring 23 so as to be rotatable around the optical axis. A ZM ring 2 to which the ZM ring 1 is bonded and fixed is held by the fixed cylinder 28 so as to be rotatable around the optical axis in a state where movement in the optical axis direction is restricted. In addition, a guide cylinder 31 is also fixed to the fixed cylinder 28.

  The guide tube 31 is provided with a plurality of straight guide grooves (not shown). One of the plurality of rectilinear guide grooves is engaged with three rollers (not shown) provided in the circumferential direction on the inner peripheral side of the rectilinear cylinder 29. Further, the second lens holding frame unit 12 that holds the second lens L2, the fifth lens holding frame unit 15 that holds the fifth lens L5, and the fourth lens holding that holds the fourth lens L4 are provided in another straight guide groove. Three rollers each provided in the circumferential direction are engaged with the outer periphery of the frame unit.

  A cam ring 30 is fitted on the outer periphery of the guide tube 31 so as to be rotatable around the optical axis in a state where movement in the optical axis direction is restricted, and a roller engaged with the straight guide groove of the guide tube 31 is fitted. Each also engages with a cam groove provided in the cam ring 30. The first lens holding frame 11 that holds the first lens L <b> 1 is fixed to the rectilinear cylinder 29. The filter frame 22 is also fixed to the rectilinear cylinder 29. Three rollers that engage with cam grooves (not shown) provided inside the MZ ring 2 are provided on the outer periphery of the rectilinear cylinder 29 in the circumferential direction. By rotating the MZ ring 2 around the optical axis, the rectilinear cylinder 29 is moved in the optical axis direction by the cam groove inside the MZ ring 2.

  The cam ring 30 rotates as the straight cylinder 29 moves in the optical axis direction. As a result, the cam ring 30 rotates around the optical axis and engages with the cam groove and the straight guide groove of the guide cylinder 31, so that the second lens holding frame unit 12, the fifth lens holding frame unit 15, and the The four-lens holding frame unit 14 moves in the optical axis direction.

  Here, the fourth lens holding frame unit is an optical image stabilization unit capable of optical image stabilization by a VCM (not shown).

  A diaphragm unit 20 is fixed to the fifth lens holding frame unit 15. The aperture unit 20 can change the aperture diameter, and can adjust the amount of light passing from the lens barrel 2 to the camera body 1. A third lens holding frame unit 13 that holds the third lens L3 is fixed to the fifth lens holding frame unit. Further, the fifth lens holding frame unit 15 is also fixed with an outer cylinder 19 that holds the seventh lens holding frame unit 17 holding the seventh lens L7 so that it can be decentered with respect to the optical axis.

  The sixth lens holding frame unit 16 that holds the sixth lens L6 is movable while sliding in the optical axis direction by a guide bar (not shown) sandwiched between the fifth lens holding frame unit 15 and the outer cylinder 19. Is retained. The sixth lens holding unit 16 includes a rack (not shown), and the driving force of a stepping motor (not shown) fixed to the fifth lens holding frame is transmitted by the rack and moves in the optical axis direction. The sixth lens L6 is a lens group that adjusts the focus of the lens barrel 2.

  FIG. 3 is a perspective view showing a state in which the seventh lens holding frame unit 17 showing the embodiment of the invention is held by the outer cylinder 19. FIG. 4 is an exploded perspective view of the seventh lens holding frame unit 17 held by the outer cylinder 19 showing the embodiment of the present invention. FIG. 5A and FIG. 5B are perspective views of the seventh lens holding frame unit 17 according to the embodiment of the present invention, with different viewpoints.

  As shown in FIGS. 3, 4, 5 (a) and 5 (b), the seventh lens holding frame unit 17 has an eccentric roller 102 held by a roller fixing screw 101 and a coaxial roller 103 is a roller insertion portion of the outer cylinder 19. It is hold | maintained at the outer cylinder 19 by fixing to the roller seat 201a of the 7th lens holding frame 201 in the state which 19a fitted. The seventh lens holding frame 17 can be eccentrically adjusted with respect to the outer cylinder 19 by rotating the eccentric roller 102 around the axis of the roller fixing screw 101. In the present embodiment, the eccentricity can be adjusted. However, the inclination may be adjusted with the same configuration using the eccentric roller.

  1 and 8 are exploded perspective views of a seventh lens holding frame unit 17 showing an embodiment of the present invention. As shown in FIGS. 1 and 8, the lens holding frame unit 17 includes a seventh lens L 7, a seventh lens holding frame 201, a lens pressing plate 301, and a light shielding sheet 401. The light shielding sheet 401 is attached to the seventh lens holding frame 201 with a double-sided tape (not shown).

  The seventh lens L7 is molded by a plastic mold and includes a lens holding frame abutting surface L7a, a lens pressing plate abutting surface L7b, a gate portion L7c which is a remaining gate during molding, and a positioning boss L7d. It is preferable that the lens holding frame contact surface L7a and the lens pressing plate contact surface L7b face each other in parallel. The seventh lens L7 includes optically effective surfaces L7e and L7f through which light rays incident on the lens barrel 2 pass.

  FIG. 9 is a front view of the seventh lens holding frame 201 showing the embodiment of the present invention. The seventh lens holding frame 201 includes a roller seat 201a, a rotation restricting portion 201b, a lens receiving surface 201c, a lens positioning hole 201d, a lens positioning elongated hole 201e, and an impact receiving portion 201f.

  FIG. 10 is a perspective view of the lens pressing plate 301 according to the embodiment of the present invention. The lens pressing plate 301 includes a cantilever portion 301a extending around the optical axis, a lens pressing surface 301b, and an impact contact surface 301c. It is preferable that the lens pressing plate 301 is formed of a resin material and the cantilevered portion 301a is integrally formed. By forming the cantilevered portion 301a from the resin material, it is possible to suppress variations in the elastic force caused by the deformation of the cantilevered portion 301a due to the tolerance of each part. That is, the maximum value of variation in elastic force due to tolerance can be reduced as compared with the case where the cantilever beam portion 301a is formed of metal or the like.

  The holding structure of the seventh lens L7, which is a plastic mold lens of this embodiment, will be described. The position of the seventh lens L7 in the direction perpendicular to the optical axis is regulated by inserting one of the two positioning bosses L7d into the lens positioning hole 201d of the seventh lens holding frame 201 and the other into the positioning slot 201e. Yes. It is preferable to restrict the position in the direction perpendicular to the optical axis with such a positioning boss, so that it is possible to suppress the positional deviation due to the backlash of the positioning hole. It is also good.

  FIG. 6 shows a side view of the lens holding frame unit according to the embodiment of the present invention, and FIG. 7 shows a side view when the lens pressing ring is assembled according to the embodiment of the present invention.

  As shown in FIG. 7A, the lens pressing plate 301 is assembled with respect to the seventh lens holding frame 201 in the direction of arrow A in FIG. Next, the lens pressing plate 301 is rotated around the optical axis with respect to the seventh lens holding frame 201 in the direction of arrow B in FIG. The state shown in FIG. 7C is a state in which the lens pressing plate 301 has been assembled into the seventh lens holding frame 201.

  In the assembled state shown in FIG. 7C, the state where the cantilevered portion 301a is deformed is maintained by the cantilevered portion 301a of the lens pressing plate 301 getting over the rotation restricting portion 201b of the seventh lens holding frame 201. . When the cantilever portion 301a is deformed, the seventh lens L7 is pressed against the seventh lens holding frame 201 in the optical axis direction by the elastic force of the cantilever portion 301a. Sandwiched between. In this state, the lens pressing plate 301 is fixed to the seventh lens holding frame 201 by bonding and fixing the region C shown in FIG. 5 with a UV adhesive. (Region C is provided at three locations equally in the phase around the optical axis.

  Accordingly, the seventh lens L7 is held in a state of being pressed against the seventh lens holding frame 201 in the optical axis direction. As shown in FIG. 7, the rotation restricting portion 201b has a convex shape where the cantilevered portion 301a gets over. By making it convex in this way, it is possible to restrict the lens pressing plate 301 from rotating in the direction opposite to the assembling direction (arrow B direction). Since it is possible to prevent rotation in the direction opposite to the assembling direction, it is preferable to have a convex shape in order to improve assemblability.

  Further, in the present embodiment, a portion to be bonded and fixed with a UV adhesive is provided on the side surface portion around the optical axis of the seventh lens holding frame 201. By providing an adhesive fixing portion on the side surface, the adhesive fixing portion is hidden on the outer cylinder 19 when the seventh lens holding frame unit 17 is formed, so there is no need to attach a sheet member or the like separately to the bonding portion, so that the appearance is preferable. . Similarly, the cantilevered portion 301a is also provided on the side surface around the optical axis, so that it is not necessary to provide a separate part and hide it.

  In addition, as shown in FIG. 5, when the lens pressing plate 301 is incorporated in the seventh lens holding frame 201, the impact contact surface 301c and the impact receiving surface 201f overlap each other when viewed in the optical axis direction. The impact contact surface 301c and the impact receiving surface 201f have a certain clearance so that they do not normally come into contact with each other, but are arranged so as to contact each other when an impact is applied to the lens barrel 2 from the outside.

  Thereby, it can suppress that the adhesion fixing part of the lens holding plate 301 and the 7th lens holding frame 201 peels. Therefore, it is preferable that the impact contact surface 301c and the impact receiving surface 201f are disposed between the adhesive fixing portions when viewed in a phase around the optical axis. This is because the portion between the adhesive fixing portions is easily deformed when subjected to an impact from the outside.

  FIG. 11A is a cross-sectional view after the lens pressing plate 301 is incorporated into the seventh lens holding frame 201 as shown in FIG. 7C described above. FIG.11 (b) is the figure which expanded the area | region shown with the dotted line part in Fig.11 (a).

  As shown in FIG. 11B, in the state in which the lens pressing ring 301 is incorporated in the seventh lens holding frame 201, the lens holding frame contact surface L7a of the seventh lens L7 becomes the lens receiving surface 201c of the seventh lens holding frame 201. Abut against. In addition, the lens pressing plate contact surface L7b contacts the lens pressing surface 301b of the lens pressing plate 301. The lens holding frame contact surface L7a and the lens pressing plate contact surface L7b of the seventh lens L7, which is a plastic mold lens, are sandwiched in parallel by the elastic force of the cantilevered portion 301a of the lens pressing plate 301.

  By making the surfaces to be held parallel, it is possible to suppress the influence of deformation on the optically effective surfaces L7e and L7f due to the elastic force from the cantilever part 301a described above.

  According to the present embodiment, the cantilever beam portion 301a having a cantilever structure extending around the optical axis can suppress the elastic force generated by the deformation of the cantilever beam portion 301a in a limited space. . Further, by integrally forming the cantilevered portion 301a with a resin material having a relatively low Young's modulus with respect to the metal, it is possible to suppress the elastic force generated by the deformation of the cantilevered portion 301a as much as possible without increasing the number of parts. it can. In addition, variation in elastic force due to tolerance of each part can be suppressed.

  By suppressing the elastic force due to the deformation of the cantilevered portion 301a, the deformation of the optical surface of the seventh lens L7 when the seventh lens L7 is sandwiched between the seventh lens holding frame 201 and the lens pressing plate 301 is suppressed. can do. Further, since the seventh lens L7 can be stably held with respect to the seventh lens holding frame 201 only by incorporating the lens pressing plate 301, no special tool is required at the time of incorporation. When the lens pressing plate 301 is urged against the seventh lens L7 and the seventh lens holding frame 201 by a tool, urging by the elastic force of the metal part is necessary from the viewpoint of repeated durability.

  Therefore, it is difficult to press the seventh lens L7 with a minimum elastic force in the same manner as in the present embodiment by assembling with a tool. Further, according to the present embodiment, the seventh lens L7 faces the lens holding frame contact surface L7a and the lens press contact surface L7b in contact with the seventh lens holding frame 201 and the lens pressing plate 301 in parallel with each other. . Thereby, it is possible to suppress the influence on the optical effective surfaces L7e and L7f of the seventh lens L7 when the seventh lens L7 is sandwiched between the seventh lens holding frame 201 and the lens pressing plate 301.

  In addition, according to the present embodiment, the seventh lens L7 is held by adhering and fixing the lens pressing plate 301 to the seventh lens holding frame 201. Since it is not necessary to directly bond and fix to the seventh lens L7, which is a plastic mold lens, the adjustment position can be stably maintained even after optical adjustment even in an adjustment group using a plastic mold lens having low hydrophilicity. Therefore, the problem that the adhesive peels off at a high temperature, a low temperature, etc., and the plastic mold lens shifts from the adjustment position to deteriorate the optical performance is solved.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  As described above, the lens barrel and the optical apparatus having the lens barrel according to the present invention can suppress the deformation of the adjustment group using the plastic mold lens and can stably hold the position at the time of optical adjustment. Therefore, it is suitable for optical devices such as digital cameras and video cameras.

DESCRIPTION OF SYMBOLS 1 ... Camera body 2 ... Lens barrel L1 ... 1st lens L2 ... 2nd lens L3 ... 3rd lens L4 ... 4th lens L5 ... 5th lens L6. .. Sixth lens L7 ... Seventh lens L8 ... Eighth lens L7a ... Lens holding frame contact surface L7b ... Lens holding plate contact surface L7c ... Gate portion L7d ... Positioning Boss L7e ... Optical effective surface L7f ... Optical effective surface 11 ... First lens holding frame unit 12 ... Second lens holding frame unit 13 ... Third lens holding frame unit 14 ... First 4 lens holding frame unit 15 ... fifth lens holding frame unit 16 ... sixth lens holding frame unit 17 ... seventh lens holding frame unit 18 ... eighth lens holding frame unit 19 ... outside Tube 19a ... Roller insertion part 20 ... diaphragm unit 21 ... substrate unit 22 ... filter frame 23 ... MF ring presser ring 24 ... MF ring 25 ... ZM ring 1 26 ... ZM ring 2
27 ... exterior ring 28 fixed cylinder 29 ... straight advance cylinder 30 ... cam ring 31 ... guide cylinder 101 ... roller stop screw 102 ... eccentric roller 103 ... coaxial roller 201 ... 7th lens holding frame 201a ... roller seat 201b ... rotation restricting portion 201c ... lens receiving surface 201d ... lens positioning hole 201e ... lens positioning slot 201f ... impact receiving portion 301 ..Lens holding plate 301a ... Cantilever 301b ... Lens holding surface 301c ... Shock contact 401 ... Light shielding sheet

Claims (12)

A lens holding frame that regulates the position of the plastic mold lens in the direction perpendicular to the optical axis;
An outer cylinder disposed on the outer diameter side of the lens holding frame and holding the lens holding frame so as to be adjustable in a direction orthogonal to the optical axis or in a direction inclined with respect to the optical axis;
A lens pressing plate that generates an urging force in the optical axis direction between the lens holding frame and the plastic mold lens;
With the biasing force, the plastic mold lens is sandwiched between the lens holding frame and the lens pressing plate, and the lens pressing plate is bonded and fixed to the lens holding frame,
The lens barrel according to claim 1, wherein the urging force is provided on one of the lens pressing plate and the lens holding frame and is generated by deformation of at least one cantilever extending in a direction around the optical axis. The plastic mold lens to be sandwiched includes a first plane part and a second plane part facing each other in parallel,
The first flat portion abuts one of the lens holding frame or the lens pressing plate;
2. The lens barrel according to claim 1, wherein the second planar portion is sandwiched between the lens holding frame and the lens pressing plate in a state where the second flat portion is in contact with the other of the lens holding frame or the lens pressing plate. .   3. The lens barrel according to claim 1, wherein the cantilever is integrally formed of a resin material that forms one of the lens holding frame and the lens pressing plate. 4.   4. The biasing force generated by the cantilevered portion is generated when the lens pressing plate is rotationally assembled around the optical axis with respect to the lens holding frame. 5. Lens barrel.   A rotation prevention unit is provided for preventing rotation of the lens holding plate with respect to the lens holding frame in a direction opposite to that during rotation of the lens holding plate in a state in which the lens holding plate is rotated with respect to the lens frame. The lens barrel according to claim 4. Position restriction in the optical axis orthogonal direction of the plastic mold lens of the lens holding frame,
A positioning protrusion provided on one of the lens holding frame and the plastic mold lens;
6. The lens barrel according to claim 1, wherein the lens barrel is performed by fitting the lens holding frame and a positioning hole provided on the other side of the plastic mold lens.   The plurality of bonding portions for bonding and fixing the lens holding frame and the lens pressing plate are provided on a side surface portion around the optical axis of the lens holding frame. The lens barrel described.   7. The lens barrel according to claim 1, wherein the cantilevered portion is disposed on an outer diameter side of the first flat surface portion and the second flat surface portion.   The lens barrel according to claim 7, wherein the lens holding frame and the lens pressing plate have an impact receiving portion at a phase between the plurality of adhesive portions provided around the optical axis. Plastic mold lenses,
A lens holding frame that regulates the position of the plastic mold lens in the direction perpendicular to the optical axis;
An outer cylinder disposed outside the lens holding frame and holding the lens holding frame so as to be adjustable in a direction orthogonal to the optical axis or in a direction inclined with respect to the optical axis;
A lens barrel that includes a lens pressing plate that is disposed on the opposite side of the plastic mold lens with respect to the lens holding frame in the optical axis direction and generates a biasing force that presses the plastic mold lens toward the lens holding frame. There,
The lens barrel according to claim 1, wherein the urging force is provided by one of the lens pressing plate and the lens holding frame and is generated by deformation of at least one cantilever extending in a direction around the optical axis.   An optical apparatus comprising the lens barrel according to any one of claims 1 to 10. With an image sensor
The optical apparatus according to claim 11, wherein the lens barrel guides light from subject light to the image sensor.