Lens barrel, imaging apparatus, and method for positioning optical lens

Abstract

To provide a lens barrel that is excellent in assemblability in assembling an optical lens, a holding member, and a hold-down member, and has good optical performance, an imaging apparatus, and a method for positioning an optical lens.SOLUTION: A lens barrel 10 comprises: a second stationary lens 310 that has a flange part 310j; a second stationary lens frame 320 that holds the second stationary lens 310; a cover 330 that holds down the second stationary lens 310 against the second stationary lens frame 320; and a positioning part 30 that performs positioning of the second stationary lens 310. The positioning part 30 has at least one projection 310b that is provided on the flange part 310j projecting in an optical axis O10 direction, and a recess 330c that is provided in the cover 330 opening toward the projection 310b side and into which the projection 310b is inserted. The recess 330c has a tapered surface 330t inclined with respect to the optical axis O10 direction, and is in contact with the projection 310b on the tapered surface 330t.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a lens barrel, an imaging device, and a method for positioning an optical lens. [Background technology]

[0002] In recent years, lens barrels are required to be both compact and to reduce manufacturing costs. To achieve this, for example, there is a tendency to adopt inexpensive plastic aspherical lenses that have high optical performance. To fix a plastic aspherical lens to a lens barrel, a method is adopted in which a gap is provided between the aspherical lens and the lens barrel, or an adhesive is used. In such a fixing method, the aspherical lens moves slightly over time or due to environmental changes, leading to deterioration of optical performance. As a configuration for preventing deterioration of optical performance, Patent Document 1 discloses a plastic lens holding mechanism having a plastic lens, a lens barrel, and a push ring that presses the plastic lens against the lens barrel. In addition, in the plastic lens holding mechanism described in Patent Document 1, the push ring has a tongue-shaped spring portion, the lens barrel has a groove, and the tongue-shaped spring portion engages with the groove to fix the plastic lens. Patent Document 2 discloses a lens module having a lens and a cylindrical lens barrel whose inner periphery is fitted with the outer periphery of the lens. In the lens module described in Patent Document 2, the lens has a tapered rib, the lens barrel has a tapered groove, and the lens is fixed by fitting the tapered rib with the tapered groove and the inner periphery of the lens barrel with the outer periphery of the lens. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-188253 [Patent Document 2] JP 2020-86447 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the plastic lens holding mechanism described in Patent Document 1, since the tongue-shaped spring part is configured to engage with the groove, if a force larger than the spring force of the tongue-shaped spring part is applied, the position of the plastic lens may be displaced. As a result, optical performance is impaired. In addition, when assembling the push ring and the lens barrel by engaging the tongue-shaped spring part with the groove, it is necessary to rotate the push ring and the lens barrel in the opposite directions relative to each other. For example, if too much force is applied during the rotation, the tongue-shaped spring part may be damaged, and assembling is poor. In the lens module described in Patent Document 2, since the lens is fixed by the engagement between the tapered rib and the tapered groove and the engagement between the inner peripheral part of the lens barrel and the outer peripheral part of the lens, deformation or floating of the lens may occur. As a result, optical performance is impaired. In addition, in such a lens fixing configuration, high dimensional accuracy is required for each part, and high assembly accuracy is required for assembling each part, and assembling is poor.

[0005] The present invention has been made in view of the above problems, and has an object to provide a lens barrel, an imaging device, and a method for positioning an optical lens that are easy to assemble when assembling an optical lens, a holding member, and a pressing member, and that have good optical performance. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the lens barrel of the present invention comprises an optical lens having a lens portion that functions as a lens and a flange portion provided on the outer periphery of the lens portion and having an expanded outer diameter; a holding member that holds the optical lens on one side of the optical axis direction of the lens portion; a pressing member that is positioned and fixed in a direction perpendicular to the optical axis direction by the holding member and presses the optical lens against the holding member to one side in the optical axis direction; and a positioning portion that positions the optical lens relative to the pressing member, wherein the positioning portion has at least one convex portion provided on one of the flange portion and the pressing member and protruding in the optical axis direction, and a concave portion provided on the other of the flange portion and the pressing member, the concave portion being open toward the convex portion side and into which the convex portion is inserted, and at least one of the convex portion and the concave portion has an inclined surface inclined with respect to the optical axis direction and contacts the other at the inclined surface. Effect of the Invention

[0007] According to the present invention, the optical lens, the holding member, and the pressing member can be easily assembled, and good optical performance can be obtained. [Brief description of the drawings]

[0008] [Figure 1] 1 is a vertical cross-sectional view showing the internal structure of a lens barrel according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the lens barrel shown in FIG. [Diagram 3] 2 is a perspective view of a bearing included in the lens barrel shown in FIG. 1. [Figure 4] 2 is a partially enlarged perspective view of a second fixed lens frame of the lens barrel shown in FIG. 1. [Diagram 5] 11 is a plan view showing the positional relationship between a second fixed lens frame and a bearing when viewed from the optical axis direction. FIG. [Figure 6] 11 is a vertical cross-sectional view showing a state in which a bearing is assembled into the second fixed lens frame. FIG. [Figure 7]FIG. 13 is a plan view showing adjustment of bearings using a jig (adjustment of inclination of the focus group) as viewed from the image side. [Figure 8] FIG. 11 is a perspective view showing adjustment of bearings using a jig (adjustment of inclination of the focus group) as viewed from the image side. [Figure 9] 2 is a perspective view of a cover of the lens barrel shown in FIG. 1. [Figure 10] 11 is a longitudinal cross-sectional view taken along the optical axis direction, showing a state in which a convex portion of a second fixed lens is inserted into a concave portion of a cover. FIG. [Figure 11] 13 is a longitudinal cross-sectional view of a lens barrel according to a second embodiment of the present invention, taken along the optical axis direction, showing a state in which a convex portion of a second fixed lens is inserted into a concave portion of a cover. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Each embodiment of the present invention will be described in detail below with reference to the drawings. However, the configurations described in each of the following embodiments are merely examples, and the scope of the present invention is not limited by the configurations described in each embodiment. For example, each part constituting the present invention can be replaced with any configuration that can exert a similar function. In addition, any configuration may be added. In addition, any two or more configurations (features) of each embodiment can be combined.

[0010] First Embodiment Hereinafter, the first embodiment will be described with reference to Figs. 1 to 10. Fig. 1 is a vertical cross-sectional view showing the internal structure of a lens barrel according to the first embodiment of the present invention. Fig. 2 is an exploded perspective view of the lens barrel shown in Fig. 1. The lens barrel 10 shown in Fig. 1 is attached to an imaging device 1000 for use. The lens barrel 10 may be configured to be detachable from the imaging device 1000, or may be fixed to the imaging device 1000 and restricted from being detached. As shown in Figs. 1 and 2, the lens barrel 10 has a first fixed lens group 100, a focus group 200, a second fixed lens group 300, a shake correction group 500, an aperture unit 600, a first adjustment lens group 700, and a second adjustment lens group 800.

[0011] The first fixed lens group 100 has a first fixed lens 110, a first fixed lens frame (first holding member) 120, a main guide bar 130, and a sub guide bar 140. The vertical cross-sectional view of FIG. 1 shows the structure of the lens barrel 10 when cut on a plane including the main guide bar 130 and the sub guide bar 140. The first fixed lens 110 is held concentrically with the first fixed lens frame 120 inside the cylindrical first fixed lens frame 120. The first fixed lens frame 120 does not need to hold the first fixed lens 110 if it is not necessary for optical design. The main guide bar 130 and the sub guide bar 140 will be described in detail later. The first fixed lens group 100 has a drive source 150, an FPC 170, a coil 180, a first magnetic shield sheet metal 190, and a second magnetic shield sheet metal 195. The first fixed lens frame 120 holds a pair of coils 180 and a pair of first magnetic shield sheet metals 190. The pair of coils 180 and the pair of first magnetic shield metal sheets 190 in this held state are arranged in the same phase as the pair of shake correction magnets 530 and the pair of yokes 540 held by the shake correction lens frame 520 that constitutes the shake correction group 500. In addition, the first fixed lens frame 120 holds a second magnetic shield metal sheet 195 so as to cover the first magnetic shield metal sheet 190.

[0012] As shown in FIG. 1, the first fixed lens frame 120 has a main guide holding portion 120a and a sub-guide holding portion 120b. One end of the main guide bar 130 on the subject side is inserted into the main guide holding portion 120a to hold the main guide bar 130. One end of the sub-guide bar 140 on the subject side is inserted into the sub-guide holding portion 120b to hold the sub-guide bar 140. The first fixed lens frame 120 is also provided with ball receiving surface portions (not shown) that come into contact with three balls (not shown) that are arranged at equal angular intervals around the optical axis O10 of the lens barrel 10 (lens portion 310a). The first fixed lens frame 120 is also provided with a hook (not shown) that engages with one end of a thrust spring (not shown). As shown in FIG. 2, the first fixed lens frame 120 holds the second adjustment lens group 800 via a plurality of second adjustment rollers 830 on the subject side. The second adjustment lens group 800 holds the first adjustment lens group 700 via a plurality of first adjustment rollers 730. The first adjustment lens group 700 has a first adjustment lens 710, a first adjustment lens frame 720, a first adjustment roller 730, and a first adjustment lens group screw (not shown). The second adjustment lens group 800 has a second adjustment lens 810, a second adjustment lens frame 820, a second adjustment roller 830, a first adjustment roller insertion part 840, and a second adjustment lens group screw (not shown). The outermost periphery of the first adjustment roller 730 is eccentric with respect to the center of the first adjustment lens group screw, and is fitted into the first adjustment roller insertion part 840 of the second adjustment lens frame 820. By rolling the first adjustment roller 730, the first adjustment lens 710 can be moved to a desired position relative to the second adjustment lens 810 and positioned. Similarly, the outermost periphery of the second adjustment roller 830 is eccentric with respect to the center of the second adjustment lens group screw, and is fitted into the second adjustment roller insertion portion 120c of the first fixed lens frame 120. By rolling the second adjustment roller 830, the second adjustment lens 810 can be moved and positioned to a desired position relative to the first fixed lens frame 120. Then, by adjusting the inclination and eccentricity of the first adjustment lens 710 and the second adjustment lens 810 with respect to the optical axis O10, good optical performance can be obtained in the lens barrel 10.

[0013] As shown in FIG. 1 and FIG. 2, the second fixed lens group 300 includes a second fixed lens (optical lens) 310, a second fixed lens frame (holding member) 320, a cover (pressing member) 330, a screw 340, and a bearing (second holding member) 400. The second fixed lens 310 includes a lens portion 310a that is provided at the center thereof and functions as a lens, and a flange portion 310j that is provided on the outer periphery of the lens portion 310a and has an expanded outer diameter. The second fixed lens 310 also includes three convex portions (projections) 310b provided on the flange portion 310j so as to protrude toward the image side (the other side) in the optical axis O10 direction. In the configuration shown in FIG. 2, the three convex portions 310b are disposed at equal intervals along the circumferential direction of the flange portion 310j, that is, disposed at equal angular intervals around the optical axis O10. Each of the convex portions 310b constitutes a positioning unit 30 that performs positioning of the second fixed lens 310 (a method for positioning an optical lens) relative to the cover 330. The number of the convex portions 310b is not limited to three, and may be, for example, one, two, or four or more, but three or more is preferable.

[0014] The second fixed lens frame 320 is composed of a cylindrical or ring-shaped member. The second fixed lens 310 is held inside the second fixed lens frame 320 from the subject side (one side) in the direction of the optical axis O10. The second fixed lens frame 320 has an opening 320a into which the bearing 400 is inserted, and a sub-guide holding portion 320b into which the other end of the sub-guide bar 140 is inserted.

[0015] A cover 330 is disposed on the image side (the other side) of the second fixed lens 310 in the direction of the optical axis O10. The cover 330 is made of a cylindrical or ring-shaped member and has a plurality of arms (biasing parts) 330a provided on its outer periphery. These arms 330a are disposed at equal intervals along the circumferential direction of the cover 330. Each arm 330a protrudes in an arc shape along the circumferential direction of the cover 330 and has elasticity. Each arm 330a engages with an engagement part 320m provided on the second fixed lens frame 320. This allows the second fixed lens 310 to be biased and held toward the subject side in the direction of the optical axis O10 relative to the second fixed lens frame 320. Furthermore, the cover 330 is connected to the second fixed lens frame 320 by the engagement between the arms 330a and the engagement part 320m. Furthermore, the cover 330 has fitting portions 330g that fit into a plurality of outer periphery fitting portions 320n provided on the outer periphery of the second fixed lens frame 320. The outer periphery fitting portions 320n and the fitting portions 330g are disposed at equal angular intervals around the optical axis O10 and fit into each other. This allows the cover 330 to be fixed in a state in which it is positioned by the second fixed lens frame 320 in an orthogonal direction (hereinafter simply referred to as the "orthogonal direction") that is orthogonal to the direction of the optical axis O10.

[0016] As shown in FIGS. 1 and 2, the focus group 200 is disposed between the first fixed lens group 100 and the second fixed lens group 300 in the direction of the optical axis O10 as a linear moving group. The focus group 200 has a focus lens 210, a focus lens frame (lens holder) 220, a rack 230, a rack spring 240, and a mask 250. The focus lens frame 220 has a fitting portion 220a into which the main guide bar 130 is slidably inserted and fitted, and a vibration prevention portion 220b which engages with the sub guide bar 140. The rack 230 is rotatably held by the focus lens frame 220. In addition, the rack 230 is urged toward a lead screw 150a provided on the output shaft of the drive source 150 by the urging force of the rack spring 240. When the driving source 150 is energized via the FPC 170, the focus group 200 moves to a predetermined position in the direction of the optical axis O10 by the meshing of the lead screw 150a and the rack 230 while being guided by the main guide bar 130 and the sub guide bar 140. This brings the optical system of the lens barrel 10 into a state in which the subject is focused. The optical image focused on the subject is formed on the imaging surface of an imaging element (not shown) such as a CMOS sensor provided in the imaging device 1000 to which the lens barrel 10 is attached. The imaging element generates image data by photoelectric conversion. Note that, for example, a stepping motor can be used as the driving source 150, but is not limited thereto.

[0017] As shown in FIG. 1, the shake correction group 500 has a shake correction lens 510, a shake correction lens frame 520, a pair of shake correction magnets 530, a pair of yokes 540, and a pair of position detection magnets (not shown). The shake correction lens 510, the pair of shake correction magnets 530, the pair of yokes 540, and the pair of position detection magnets are held by the shake correction lens frame 520. The pair of shake correction magnets 530 are arranged on the opposite sides to each other across the optical axis O10. The pair of yokes 540 are arranged on the subject side in the optical axis O10 direction, facing the pair of shake correction magnets 530. The pair of position detection magnets are arranged on the opposite sides to each other across the optical axis O10, facing the pair of shake correction magnets 530. Note that the shake correction group 500 is provided with a position detection magnet, but is not limited thereto. For example, depending on the configuration of the shake correction group 500, the shake correction magnet 530 may also be used as a position detection magnet. The vibration correction lens frame 520 is provided with ball receiving surface portions (not shown) that come into contact with the three balls, and a hook (not shown) with which the other end of the thrust spring engages. The ball is sandwiched between the ball receiving surface portion of the first fixed lens frame 120 and the ball surface receiving portion of the vibration correction lens frame 520 by the biasing force of the thrust spring. This allows the ball to roll, and therefore the vibration correction lens frame 520 is movable in the perpendicular direction.

[0018] The aperture unit 600 is disposed on the subject side of the shake correction group 500, and is held to the second fixed lens frame 320 by screws (not shown).

[0019] Next, a correction method for correcting image blur in the lens barrel 10 will be described. As described above, the lens barrel 10 is provided with a pair of shake correction magnets 530 and a pair of coils 180, which are arranged in the same phase, and a pair of first magnetic shielding metal plates 190. The lens barrel 10 is also provided with a flexible board (not shown). A position detection magnet and a pair of Hall elements arranged in the same phase as the position detection magnet are mounted on this flexible board. When the coil 180 is in a conducting state, the Lorentz force generated between the coil 180 and the shake correction magnet 530 causes the shake correction group 500 to move in a direction perpendicular to the first fixed lens group 100. The Hall element detects the magnetic force of the position detection magnet. The image pickup device 1000 control unit (not shown) can calculate the position of the shake correction group 500 with respect to the first fixed lens group 100 based on the detection result of the Hall element. Furthermore, the control unit of the imaging device 1000 controls the voltage applied to the coil 180 based on image blur information from a gyro sensor (not shown) provided in the lens barrel 10 or the imaging device 1000. This control allows the shake correction group 500 to move in the orthogonal direction in which image blur correction is possible. This makes it possible to obtain still images and moving images in which image blur of the subject image has been corrected, even if vibrations such as camera shake occur during shooting.

[0020] When the coil 180 is energized, a magnetism is generated between the coil 180 and the shake correction magnet 530. The first magnetic shield sheet metal 190 can prevent the influence of this magnetism on the imaging element. In order to further enhance the magnetic shielding effect of the first magnetic shield sheet metal 190, a second magnetic shield sheet metal 195 is disposed on the imaging element side of the first magnetic shield sheet metal 190. In this embodiment, the second magnetic shield sheet metal 195 is integrally configured to cover the pair of first magnetic shield sheet metals 190, but is not limited thereto. For example, the second magnetic shield sheet metal 195 may be divided into a plurality of parts according to the arrangement of each of the first magnetic shield sheet metals 190.

[0021] Next, an adjustment method for adjusting the tilt of the focus group 200 will be described. Fig. 3 is a perspective view of a bearing provided in the lens barrel shown in Fig. 1. The direction in which the bearing 400 is viewed is different between Fig. 3(a) and Fig. 3(b). Fig. 4 is a partially enlarged perspective view of a second fixed lens frame provided in the lens barrel shown in Fig. 1. The direction in which the second fixed lens frame 320 is viewed is different between Fig. 4(a) and Fig. 4(b).

[0022] As shown in Figs. 3(a) and 3(b), the bearing 400 has a cylindrical main body 400j, a plurality of flanges 400a integrally formed on an outer circumferential portion 400i of the main body 400j, and a plurality of protrusions 400b on the outer circumferential portion 400i of the main body 400j. The plurality of flanges 400a are arranged at equal intervals along the circumferential direction on one end side of the main body 400j. Moreover, each of the flanges 400a protrudes in the perpendicular direction. The number of the flanges 400a is three in the configuration shown in Fig. 3, but is not limited thereto. The plurality of protrusions 400b are arranged at equal intervals along the circumferential direction on the other end side of the main body 400j. Moreover, each of the protrusions 400b protrudes in the perpendicular direction. The number of the protrusions 400b is the same as the number of the flanges 400a in the configuration shown in Fig. 3, that is, three, but is not limited thereto. When viewed from the direction of optical axis O10, flange portion 400a and protrusion portion 400b are disposed at positions where they do not overlap. A holding portion 400c that holds the other end (imaging surface side) of main guide bar 130 is provided on the protrusion portion 400b side of bearing 400.

[0023] The outermost periphery of each flange 400a is provided with a fitting surface 400d curved in an arc shape centered on the central axis of the main body 400j. The protrusion 400b side of each flange 400a is provided with an abutment surface 400e that abuts against the abutment surface 320c (see FIG. 4(a)) of the second fixed lens frame 320. Both the abutment surface 320c and the abutment surface 400e are flat surfaces parallel to the orthogonal direction. A groove (hereinafter referred to as an "adhesive groove 400f") used for bonding to the second fixed lens frame 320 is provided near the outer periphery of the surface opposite to the abutment surface 400e of the flange 400a. The main body 400j is provided with a jig receiving surface 400g between adjacent flanges 400a against which a jig 20 (see FIG. 7) used for adjusting the tilt of the focus group 200 abuts. The jig receiving surface 400g is an inclined plane inclined with respect to the central axis of the main body 400j. Each protrusion 400b is provided in the same phase as each jig receiving surface 400g. The protrusion 400b and the jig receiving surface 400g are provided in the same phase, but this is not limited thereto. A restricting surface 400h is provided on the flange 400a side of each protrusion 400b. The restricting surface 400h is a plane parallel to the orthogonal direction.

[0024] As shown in FIG. 4(a) and (b), the second fixed lens frame 320 has an abutment surface 320c that abuts against the abutment surface 400e of the bearing 400, and a notch portion 320d into which the protrusion portion 400b of the bearing 400 is inserted. The second fixed lens frame 320 also has a plurality of fitting surfaces 320e facing the opening 320a, and an inner wall 320h provided between adjacent fitting surfaces 320e. Both the fitting surfaces 320e and the inner wall 320h are curved in an arc shape centered on the central axis of the opening 320a. The second fixed lens frame 320 has a first adhesive portion 320f provided in the same phase as the fitting surface 320e, and a second adhesive portion 320g provided in the same phase as the inner wall 320h. The second fixed lens frame 320 has a restriction surface 320i provided on the back side of the abutment surface 320c. The restriction surface 320i is a plane parallel to the orthogonal direction.

[0025] To assemble the bearing 400 and the second fixed lens frame 320 having such a configuration, first, one end of the main guide bar 130 on the subject side is inserted into the main guide holding portion 120a of the first fixed lens frame 120. In addition, one end of the sub-guide bar 140 on the subject side is inserted into the sub-guide holding portion 120b at the same time. At this time, the fitting portion 220a of the focus lens frame 220 in which the focus lens 210, rack 230, rack spring 240, and mask 250 are assembled is inserted into the main guide bar 130 in advance. This allows the focus group 200 to be assembled into the first fixed lens group 100. Next, the drive source 150 and the FPC 170 are assembled from the side of the second fixed lens frame 320 so that the rack 230 and the lead screw 150a mesh with each other, and are fixed to the second fixed lens frame 320 with the screw 160. Then, the second fixed lens frame 320 is assembled into the first fixed lens group 100 while inserting the other end of the sub-guide bar 140 on the image side into the sub-guide holding portion 320b of the second fixed lens frame 320. In this state, the second fixed lens frame 320 is fixed to the first fixed lens frame 120 by a plurality of screws 340. After that, the bearing 400 is assembled into the opening 320a from the cover 330 side so as to match the phase of the protrusion 400b of the bearing 400 and the cutout portion 320d of the second fixed lens frame 320. By going through such an assembly process, the bearing 400 and the second fixed lens frame 320 can be assembled, and then, as described later, the inclination of the focus group 200 can be adjusted. In addition, when viewed from the optical axis O10 direction, a part of the bearing 400 is arranged overlapping with the second fixed lens 310, which allows the lens barrel 10 to be made smaller in size.

[0026] FIG. 5 is a plan view showing the positional relationship between the second fixed lens frame and the bearing when viewed from the optical axis direction. FIG. 5(a) is a diagram showing the assembly phase of the bearing 400. FIG. 5(b) is a diagram showing the assembly phase (first position) of the focus group 200 in the bearing 400 when not adjusted. FIG. 5(c) is a diagram showing the assembly phase (second position) of the focus group 200 in the bearing 400 when the inclination of the focus group 200 is adjusted. FIG. 6 is a vertical cross-sectional view showing a state in which the bearing is assembled in the second fixed lens frame. FIG. 6(a) is a vertical cross-sectional view showing an engagement state between the bearing 400 and the second fixed lens frame 320 at the first position shown in FIG. 5(b). FIG. 6(b) is a vertical cross-sectional view showing an engagement state between the bearing 400 and the second fixed lens frame 320 at the second position shown in FIG. 5(c). FIG. 7 is a plan view of the adjustment of the bearing using a jig (adjustment of the inclination of the focus group) when viewed from the image side. FIG. 8 is a perspective view of the adjustment of the bearings using a jig (adjustment of the inclination of the focus group) as viewed from the image side.

[0027] 5(a), the bearing 400 is inserted into the opening 320a of the second fixed lens frame 320. This causes the abutment surface 320c of the second fixed lens frame 320 and the abutment surface 400e of the bearing 400 to abut against each other. As the bearing 400 is inserted into the opening 320a of the second fixed lens frame 320, the other end of the main guide bar 130 on the image side is inserted into the holding portion 400c of the bearing 400. The bearing 400 is held by the second fixed lens frame 320 so as to be rotatable in both the directions of the arrows α and β.

[0028] By rotating the bearing 400 in the direction of the arrow α from the assembled phase state of FIG. 5(a), the state shown in FIG. 5(b) and FIG. 6(a) is obtained. In the state shown in FIG. 5(b) and FIG. 6(a), the bearing 400 rotates to a first position relative to the second fixed lens frame 320. When the bearing 400 is in the first position, the fitting surface 400d of the bearing 400 fits with the fitting surface 320e of the second fixed lens frame 320. In addition, the restricting surface 400h of the bearing 400 abuts against the restricting surface 320i of the second fixed lens frame 320. This restricts the movement of the bearing 400 in the orthogonal direction. In addition, the bonding groove 400f of the bearing 400 and the first bonding portion 320f of the second fixed lens frame 320 are in the same phase, and the bearing 400 and the second fixed lens frame 320 can be bonded to each other. In this state, the bearing 400 can be fixed to the second fixed lens frame 320 by applying a predetermined adhesive to the adhesive grooves 400f and near the first adhesive portions 320f.

[0029] On the other hand, by rotating the bearing 400 in the direction of the arrow β from the state shown in FIG. 5(a), the state shown in FIG. 5(c) and FIG. 6(b) is obtained. In the state shown in FIG. 5(c) and FIG. 6(b), the bearing 400 moves to a second position relative to the second fixed lens frame 320. When the bearing 400 is in the second position, the fitting surface 400d of the bearing 400 faces the inner wall 320h of the second fixed lens frame 320. In addition, the adhesive groove 400f of the bearing 400 and the second adhesive portion 320g of the second fixed lens frame 320 are in the same phase, and the bearing 400 and the second fixed lens frame 320 can be bonded to each other. In this state, the bearing 400 can be fixed to the second fixed lens frame 320 by applying a predetermined adhesive to the adhesive groove 400f and the vicinity of the second adhesive portion 320g. Moreover, when the bearing 400 is in the second position, the abutment surface 400e of the bearing 400 abuts against the abutment surface 320c of the second fixed lens frame 320. In the second fixed lens frame 320, the diameter of the inner wall 320h is larger than the diameter of the fitting surface 320e, so that a gap 50 is formed between the fitting surface 400d and the inner wall 320h (see FIG. 5(c)). The restriction surface 400h of the bearing 400 does not exist at a position facing the restriction surface 320i of the second fixed lens frame 320, and a gap 60 is formed on the image side of the restriction surface 320i (see FIG. 6(c)). In this manner, when the bearing 400 is held by the second fixed lens frame 320 in the second position, only the abutment surface 400e of the bearing 400 abuts against the abutment surface 320c of the second fixed lens frame 320, and the bearing 400 is movable in the perpendicular direction. In this state, when the bearing 400 is moved to an arbitrary position in the perpendicular direction using the jig 20 (see Figs. 7 and 8), the main guide bar 130 held by the bearing 400 tilts. This makes it possible to tilt the focus group 200, and therefore to adjust the inclination of the focus group 200.

[0030] Furthermore, when the bearing 400 is rotated in the direction of the arrow α, the bearing 400 is fixed to the second fixed lens frame 320. In this state, the tilt of the focus group 200 is inspected. If the inspection result confirms that the tilt of the focus group 200 meets a predetermined standard, a predetermined adhesive is applied to the adhesive groove 400f and the first adhesive portion 320f. This makes it possible to fix the bearing 400 without adjusting the tilt of the focus group 200.

[0031] On the other hand, if the tilt inspection of the focus group 200 shows that the tilt of the focus group 200 does not meet the predetermined standard, the bearing 400 is rotated in the direction of the arrow β to move the bearing 400 to the second position, and the tilt is adjusted by the jig 20. After that, a predetermined adhesive is applied to the adhesive groove 400f and the second adhesive portion 320g to fix the bearing 400 to the second fixed lens frame 320. In this way, the tilt adjustment of the focus group 200 needs to be performed only when the bearing 400 cannot be fixed at the first position. As a result, when the tilt adjustment of the focus group 200 is not necessary, the adjustment can be omitted, and the productivity of the lens barrel 10 can be improved.

[0032] Furthermore, when the bearing 400 is in the second position, the protrusion 400b and the cutout 320d are arranged so that the abutment surface 320c is not positioned toward the optical axis O10. This prevents the jig 20 from overlapping with the optical axis O10 when adjusting the inclination of the focus group 200, as shown in Fig. 7. This makes it possible to easily adjust the inclination.

[0033] In the bearing 400, the diameter of the fitting surface 400d is "R_400d", and the diameter of the outer periphery 400i of the main body 400j is "R_400i". In the second fixed lens frame 320, the diameter of the inner wall 320h is "r_320h", and the diameter of the inner periphery wall 320j is "r_320j". In this case, the relationship (R_400d-r_320h)<(r_320j-R_400i) is satisfied. As a result, when the bearing 400 is moved in the orthogonal direction, the fitting surface 400d of the bearing 400 becomes a restricting surface that restricts the movement of the bearing 400, and contacts the inner wall 320h of the second fixed lens frame 320. In other words, in a state where the inclination adjustment is possible, the fitting surface 400d and the inner wall 320h are in the closest positional relationship in the orthogonal direction. As described above, the adhesive groove 400f is provided on the image side of the fitting surface 400d. Also, the second adhesive portion 320g is provided in the same phase as the inner peripheral wall 320j. Therefore, when the bearing 400 is rotated in the direction of the arrow β to adjust the inclination, the adhesive groove 400f and the second adhesive portion 320g are closest to each other, so that the adhesive can be applied efficiently.

[0034] Next, the positioning unit 30 for positioning the second fixed lens 310 will be described. As described above, the second fixed lens 310 is provided to protrude from the flange portion 310j and has three convex portions 310b constituting the positioning unit 30 (see FIG. 2). The three convex portions 310b are arranged at equal intervals along the circumferential direction of the flange portion 310j, that is, arranged at equal angular intervals around the optical axis O10. Each convex portion 310b has a size that can be formed on the flange portion 310j, and its outer diameter forms a constant cylindrical shape along the optical axis O10 direction. In addition, the outer diameter of each convex portion 310b is smaller than the outer diameter of the second fixed lens 310. This allows each convex portion 310b to be formed with high dimensional accuracy.

[0035] FIG. 9 is a perspective view of the cover of the lens barrel shown in FIG. 1. As shown in FIG. 9, the cover 330 has three recesses 330c provided on the same side as the arm portion 330a and the fitting portion 330g. In the configuration shown in FIG. 9, the three recesses 330c are arranged at equal intervals along the circumferential direction of the three recesses 330c, that is, arranged at equal angular intervals around the optical axis O10. In this embodiment, each recess 330c is configured as a groove extending (radially) along the radial direction centered on the optical axis O10. Each of these recesses 330c constitutes the positioning portion 30 in the same manner as each of the convex portions 310b of the second fixed lens 310. The number of recesses 330c is the same as the number of convex portions 310b. Each recess 330c is provided to open toward one of the convex portions 310b, and the convex portion 310b is inserted into the recess 330c. The number of recesses 330c is not limited to three, so long as it is the same as the number of protrusions 310b.

[0036] FIG. 10 is a longitudinal sectional view of the state in which the convex portion of the second fixed lens is inserted into the concave portion of the cover, cut along the optical axis direction. FIG. 10(a) is a longitudinal sectional view of the present embodiment. FIG. 10(b) is a longitudinal sectional view of a modified example of the present embodiment. As shown in FIG. 10(a), the concave portion 330c has a pair of tapered surfaces 330t in which the width of the groove gradually increases toward the convex portion 310b side. That is, each side surface of the concave portion 330c is an inclined surface inclined with respect to the optical axis O10 direction. In addition, the maximum width W330c of the tapered surface 330t of the concave portion 330c is larger than the outer diameter (maximum outer diameter) φD310b of the convex portion 310b. As a result, when the convex portion 310b is inserted, the concave portion 330c contacts the top of the convex portion 310b at the tapered surface 330t. This contact is a point contact.

[0037] Incidentally, the fitting portion 330g of the cover 330 fits into the outer periphery of the second fixed lens frame 320. This positions the cover 330 relative to the second fixed lens frame 320 in the orthogonal direction. The second fixed lens 310 is disposed with the flange portion 310j spaced apart from the inner periphery wall 320j of the second fixed lens frame 320. When the cover 330, the second fixed lens 310, and the second fixed lens frame 320 are assembled, the convex portion 310b is inserted into the concave portion 330c, and the convex portion 310b and the tapered surface 330t of the concave portion 330c come into point contact. At this time, the second fixed lens 310 is biased in the direction of the optical axis O10 by the biasing force from each arm portion 330a of the cover 330. Due to the synergistic effect of the point contact and the biasing force, the second fixed lens 310 is more accurately positioned (positionally restricted) in the direction of the optical axis O10. As described above, the cover 330 is positioned in the orthogonal direction relative to the second fixed lens frame 320. Along with this positioning, the second fixed lens 310 is also positioned in the orthogonal direction.

[0038] As described above, the positioning unit 30 can perform at least positioning in the optical axis O10 direction of the second fixed lens 310 and positioning in the orthogonal direction of the second fixed lens 310. This allows the lens barrel 10 to have good optical performance. As described above, the three convex portions 310b and the three concave portions 330c are respectively arranged at equal angular intervals around the optical axis O10. This allows the second fixed lens 310 to be positioned stably. Although a pair of tapered surfaces 330t is provided, this is not limiting and only one may be provided.

[0039] The assembly of the cover 330, the second fixed lens 310, and the second fixed lens frame 320 is a simple assembly in which these members are overlapped in the optical axis O10 direction and the convex portion 310b is inserted into the concave portion 330c. This makes the lens barrel 10 easy to assemble. In addition, in this assembly, the second fixed lens 310 can be firmly fixed without using adhesives or the like. Even if the bearing portion 400 needs to be readjusted after that, the second fixed lens 310 can be easily removed, making the readjustment possible. Even if there is a variation in the positional accuracy of the convex portion 310b or the tapered surface 330t, for example, the variation can be offset by the elasticity of the arm portion 330a or the groove shape of the concave portion 330c. The cover 330 is made of a cylindrical or ring-shaped member as described above, and has an opening 330h that penetrates in the optical axis O10 direction and opens in a circular shape on the inside. The amount of light passing through the second fixed lens 310 can be restricted by the opening 330h.

[0040] 10(b), in the modified example, as the positioning portion 30, a recess 310c is provided in the second fixed lens 310, and a protrusion 330b is provided in the cover 330. The recess 310c has a pair of tapered surfaces 310s, and each of the tapered surfaces 310s contacts the top of the protrusion 330b. As a result, similar to the configuration shown in FIG. 10(a), the lens barrel 10 is easy to assemble when assembling the cover 330, the second fixed lens 310, and the second fixed lens frame 320, and has good optical performance.

[0041] <Second embodiment> Hereinafter, the second embodiment will be described with reference to Fig. 11, focusing on the differences from the previously described embodiment, and the description of similar matters will be omitted. Fig. 11 is a vertical cross-sectional view of a lens barrel according to a second embodiment of the present invention, cut along the optical axis direction in a state in which the convex portion of the second fixed lens is inserted into the concave portion of the cover. Fig. 11(a) is a vertical cross-sectional view of this embodiment. Fig. 11(b) is a vertical cross-sectional view of a modified example of this embodiment.

[0042] As shown in FIG. 11(a), the second fixed lens 310 is provided with a convex portion 310f, and the cover 330 is provided with a concave portion 330f, as the positioning portion 30. The convex portion 310f has a tapered surface 310g whose outer diameter gradually decreases toward the concave portion 330f side. That is, the outer peripheral surface of the convex portion 310f is an inclined surface inclined with respect to the optical axis O10 direction. The concave portion 330f is formed of a groove, and its width W330f is constant along the optical axis O10 direction. The maximum outer diameter φD310f of the tapered surface 310g of the convex portion 310f is larger than the width W330f (maximum width of the concave portion 330f). As a result, when the convex portion 310f is inserted into the concave portion 330f, the middle of the tapered surface 310g comes into point contact with the edge portion (open portion) 330k of the concave portion 330f.

[0043] As shown in FIG. 11(b), in the modified example, as the positioning portion 30, a recess 310p formed of a groove is provided in the second fixed lens 310, and a protrusion 330p is provided in the cover 330. The protrusion 330p has a tapered surface 330q whose outer diameter gradually decreases toward the recess 310p side. That is, the outer peripheral surface of the protrusion 330p is an inclined surface inclined with respect to the optical axis O10 direction. When the protrusion 330p is inserted into the recess 310p, the middle of the tapered surface 330q comes into point contact with the edge 310r of the recess 310p.

[0044] 11(a) and (b), in this embodiment, as in the first embodiment, the lens barrel 10 has excellent assembly properties when assembling the cover 330, the second fixed lens 310, and the second fixed lens frame 320, and also has good optical performance.

[0045] As described above, the positioning unit 30 has at least one convex portion provided on one of the flange portion 310j of the second fixed lens 310 and the cover 330, and a concave portion provided on the other of the flange portion 310j and the cover 330. At least one of the convex portion and the concave portion has an inclined surface and can contact the other at the inclined surface. In addition, the contact at the inclined surface is a point contact, but is not limited to this, and can be a line contact depending on the shape of the convex portion and the concave portion, for example.

[0046] The disclosure of this embodiment includes the following configurations and methods. (Configuration 1) An optical lens having a lens portion that functions as a lens and a flange portion that is provided on the outer periphery of the lens portion and has an expanded outer diameter; a holding member that holds the optical lens on one side of the lens portion in the optical axis direction; a pressing member that is fixed in a state where it is positioned in a direction perpendicular to the optical axis direction by the holding member and that presses the optical lens against the holding member to one side in the optical axis direction; a positioning unit that positions the optical lens relative to the pressing member, the positioning portion has at least one protruding portion provided on one of the flange portion and the pressing member so as to protrude in the optical axis direction, and a recessed portion provided on the other of the flange portion and the pressing member so as to open toward the protruding portion, into which the protruding portion is inserted, At least one of the convex portion and the concave portion has an inclined surface inclined with respect to the optical axis direction, and contacts the other at the inclined surface. (Configuration 2) The lens barrel according to configuration 1, wherein the positioning section performs positioning of the optical lens in at least the optical axis direction out of positioning of the optical lens in the optical axis direction and positioning of the optical lens in the perpendicular direction. (Configuration 3) The lens barrel according to configuration 1 or 2, wherein the contact on the inclined surface is a point contact or a line contact. (Configuration 4) The lens barrel according to any one of configurations 1 to 3, wherein the recess is formed as a groove extending in a radial direction centered on the optical axis. (Configuration 5) The lens barrel according to configuration 4, wherein the recess has a tapered surface in which the width of the groove gradually increases toward the protrusion, and the tapered surface serves as the inclined surface. (Configuration 6) The protrusion is cylindrical, 6. The lens barrel according to configuration 5, wherein a maximum width of the tapered surface of the recess is greater than a maximum outer diameter of the protrusion. (Configuration 7) The lens barrel according to any one of Configurations 1 to 6, wherein the convex portion is cylindrical. (Configuration 8) The lens barrel according to configuration 7, wherein the convex portion has a tapered surface whose outer diameter gradually decreases toward the concave portion, the tapered surface being the inclined surface. (Configuration 9) The recess is formed of a groove extending in a radial direction centered on the optical axis, 9. The lens barrel according to configuration 8, wherein the maximum outer diameter of the tapered surface of the convex portion is greater than the maximum width of the groove. (Configuration 10) The lens barrel according to any one of configurations 1 to 9, wherein three or more of each of the convex portions and the concave portions are disposed. (Configuration 11) The lens barrel according to configuration 10, wherein the three or more convex portions and the three or more concave portions are respectively disposed at equal angular intervals around the optical axis. (Configuration 12) The lens barrel according to any one of configurations 1 to 11, wherein the flange portion of the optical lens is disposed at a distance from the holding member. (Structure 13) The lens barrel described in any one of Structures 1 to 12, characterized in that the pressing member has a biasing portion that biases the optical lens toward one side in the optical axis direction relative to the holding member, and is connected to the holding member via the biasing portion. (Configuration 14) The lens barrel according to any one of configurations 1 to 13, wherein the pressing member has a circular opening penetrating the pressing member in the optical axis direction. (Configuration 15) The lens barrel according to any one of configurations 1 to 14, wherein the holding member and the pressing member are each formed of a cylindrical or ring-shaped member. (Configuration 16) An imaging device comprising the lens barrel according to configuration 1. (Method 1) An optical lens having a lens portion that functions as a lens and a flange portion that is provided on the outer periphery of the lens portion and has an expanded outer diameter; a holding member that holds the optical lens on one side of the lens portion in the optical axis direction; a pressing member that is fixed in a state where the optical lens is positioned in a direction perpendicular to the optical axis direction by the holding member and that urges the optical lens toward one side in the optical axis direction with respect to the holding member to press the optical lens, at least one protrusion protruding in the optical axis direction is provided on one of the flange portion and the pressing member, and a recess opening toward the protrusion and into which the protrusion is inserted is provided on the other of the flange portion and the pressing member; A method for positioning an optical lens, comprising providing at least one of the convex portion and the concave portion with an inclined surface inclined with respect to the optical axis direction, and contacting the other with the inclined surface.

[0047] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0048] 10 Lens barrel 30 Positioning part 310 Second fixed lens (optical lens) 310b Convex portion (protrusion) 310j flange 320 Second fixed lens frame (holding member) 330 Cover (holding member) 330c recess 330t tapered surface O10 optical axis

Claims

1. An optical lens having a lens portion that functions as a lens, and a flange portion provided on the outer peripheral portion of the lens portion and having an enlarged outer diameter, a holding member that holds the optical lens on one side in the optical axis direction of the lens portion, a pressing member that is fixed in a state of being positioned in a direction orthogonal to the optical axis direction by the holding member, and biases and presses the optical lens toward one side in the optical axis direction with respect to the holding member, and a positioning portion that positions the optical lens with respect to the pressing member, wherein the positioning portion includes at least one convex portion provided to protrude in the optical axis direction on one of the flange portion and the pressing member, and a concave portion provided to open toward the convex portion side on the other of the flange portion and the pressing member and into which the convex portion is inserted, and at least one of the convex portion and the concave portion has an inclined surface inclined with respect to the optical axis direction, and the lens barrel is characterized in that the other contacts the inclined surface.

2. The lens barrel according to claim 1, wherein the positioning portion performs at least positioning in the optical axis direction among positioning in the optical axis direction of the optical lens and positioning in the orthogonal direction of the optical lens.

3. The lens barrel according to claim 1, wherein the contact on the inclined surface is point contact or line contact.

4. The lens barrel according to claim 1, wherein the concave portion is constituted by a groove extending along a radial direction centered on the optical axis.

5. The lens barrel according to claim 4, wherein the concave portion has a tapered surface whose width gradually increases toward the convex portion side, and the tapered surface of the concave portion serves as the inclined surface.

6. The convex portion has a cylindrical shape, and the lens barrel according to claim 5, wherein the maximum width at the tapered surface of the concave portion is larger than the maximum outer diameter of the convex portion.

7. The lens barrel according to claim 1, wherein the convex portion has a cylindrical shape.

8. The lens barrel according to claim 7, wherein the convex portion has a tapered surface whose outer diameter gradually decreases toward the concave portion side, and the tapered surface of the convex portion serves as the inclined surface.

9. The concave portion is constituted by a groove extending along a radial direction centered on the optical axis, The lens barrel according to claim 8, wherein the maximum outer diameter of the tapered surface of the convex portion is larger than the maximum width of the groove.

10. The lens barrel according to claim 1, wherein three or more of the convex portions and the concave portions are respectively arranged.

11. The lens barrel according to claim 10, wherein the three or more convex portions and the three or more concave portions are respectively arranged at equal angular intervals around the optical axis.

12. The lens barrel according to claim 1, wherein the flange portion of the optical lens is arranged spaced apart from the holding member.

13. The lens barrel according to claim 1, wherein the pressing member has a biasing portion that biases the optical lens toward one side in the optical axis direction with respect to the holding member, and is connected to the holding member via the biasing portion.

14. The lens barrel according to claim 1, wherein the pressing member has an opening that penetrates in the optical axis direction and opens in a circular shape.

15. The lens barrel according to claim 1, wherein the holding member and the pressing member are each composed of a member having a cylindrical shape or a ring shape.

16. An imaging device comprising the lens barrel according to claim 1.

17. An optical lens having a lens portion that functions as a lens, and a flange portion provided on an outer peripheral portion of the lens portion and having an enlarged outer diameter, a holding member that holds the optical lens on one side in the optical axis direction of the lens portion, a positioning method of the optical lens in a lens barrel including a pressing member that is fixed in a state of being positioned in a direction orthogonal to the optical axis direction by the holding member and biases and presses the optical lens toward one side in the optical axis direction with respect to the holding member, wherein at least one convex portion protruding in the optical axis direction is provided on one of the flange portion and the pressing member, and a concave portion that opens toward the convex portion side and into which the convex portion is inserted is provided on the other of the flange portion and the pressing member, and at least one of the convex portion and the concave portion is provided with an inclined surface inclined with respect to the optical axis direction, and the other is brought into contact with the inclined surface.

Images