Lens unit, lens barrel, and adjustment method

Abstract

To improve optical performance without an increase in size.SOLUTION: A second lens unit 20 of the present invention has: a second lens holding frame 22 that holds a reference lens 25 of a plurality of lenses; a first adjustment frame 26 that holds a first adjustment lens 24 of the plurality of lenses, and is adjustable in an optical axis orthogonal direction relative to the second lens holding frame 22; and a second adjustment frame 27 that holds a second adjustment lens 23 of the plurality of lenses, and is adjustable in the optical axis orthogonal direction relative to the second lens holding frame 22. The first adjustment frame 26 and the second adjustment frame 27 are arranged on an object side in an optical axis direction relative to the second lens holding frame 22.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a lens unit and the like. In particular, it relates to a lens unit and the like used in an imaging device.

Background Art

[0002] Currently, network cameras, so-called surveillance cameras, are installed in various places such as cities and factories. In recent years, due to high pixel density and miniaturization, surveillance cameras are required to have high optical performance. In order to achieve high optical performance, decentering adjustment may be performed to correct lens variations and misalignment between lenses that occur during the manufacturing process.

[0003] Patent Document 1 discloses a technique for performing decentering adjustment of a lens. Specifically, Patent Document 1 discloses that decentering adjustment is performed by moving a plurality of lens holding frames in the housing in a direction orthogonal to the optical axis of the lens, and fixing them using a press ring.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique of Patent Document 1, an adjustment lens holding frame is arranged on the image side in the optical axis direction with respect to the lens holding frame that holds the reference lens. Various components are arranged on the image side in the optical axis direction. Therefore, since the adjustment mechanism for adjusting the lens holding frame and various components are arranged close to each other, it is necessary to provide a space so that they do not interfere with each other, which may cause the entire device to become larger.

[0006] The present invention has been made in view of the above-described problems, and an object thereof is to improve optical performance without increasing the size.

Means for Solving the Problems

[0007] The present invention is a lens unit having a plurality of lenses, including a holding frame that holds a first lens among the plurality of lenses, a first adjustment frame that holds a first adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, and a second adjustment frame that holds a second adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, wherein the first adjustment frame and the second adjustment frame are arranged on the object side in the optical axis direction with respect to the holding frame.

Effects of the Invention

[0008] According to the present invention, it is possible to improve optical performance without increasing the size.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0010] Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings. <First Embodiment> FIG. 1 is a perspective view of the imaging device 1. In each figure including FIG. 1, the optical axis O of the imaging device 1 is indicated by a dashed line. Among the optical axis directions, the side of the first lens unit 10 described later is referred to as the object side (or front side), and the side of the imaging element unit 300 described later is referred to as the image side (or rear side). FIG. 2 is an exploded perspective view of the imaging device 1.

[0011] The imaging device 1 includes a lens barrel 100, an imaging element unit 300, and the like. The lens barrel 100 of the present embodiment is configured to include three lens units. Specifically, the lens barrel 100 includes an imaging optical system including a first lens unit 10, a second lens unit 20, and a third lens unit 30, a front housing member 50, and a rear housing member 51.

[0012] The first lens unit 10 (first group lens unit) has a first lens group 11 and a first lens holding frame 12. The first lens group 11 is held by the first lens holding frame 12. The first lens holding frame 12 is engaged with an axial guide bar 52 and is supported so as to be movable in the optical axis direction. Further, the first lens holding frame 12 is also engaged with an axial guide bar 53, and the rotation around the guide bar 52 is restricted. Further, the first lens holding frame 12 rotatably holds a first group rack 13. The first group rack 13 is engaged with a lead screw portion of a first group drive unit 56 including an actuator such as a stepping motor. Therefore, when the lead screw portion of the first group drive unit 56 rotates, the first lens holding frame 12 moves in the optical axis direction together with the first group rack 13.

[0013] FIG. 3 is an exploded perspective view of the second lens unit 20 (optical adjustment group). The second lens unit 20 has a second lens group 21. The second lens group 21 is a zoom lens group including a plurality of lenses. Specifically, the second lens group 21 includes a reference lens 25, a first adjustment lens 24, and a second adjustment lens 23.

[0014] The reference lens 25 is held by a second lens holding frame 22. The first adjustment lens 24 is composed of two lenses (see FIG. 4 described later) and is held by a first adjustment frame 26. The first adjustment frame 26 is held by the second lens holding frame 22. The first adjustment frame 26 is located on the object side in the optical axis direction with respect to the second lens holding frame 22. Also, the first adjustment frame 26 is adjustable in a direction orthogonal to the optical axis with respect to the second lens holding frame 22. The second adjustment lens 23 is held by a second adjustment frame 27. The second adjustment frame 27 is held by the second lens holding frame 22 via the first adjustment frame 26. The second adjustment frame 27 is located on the object side in the optical axis direction with respect to the second lens holding frame 22 and the first adjustment frame 26. Also, the second adjustment frame 27 is adjustable in a direction orthogonal to the optical axis with respect to the second lens holding frame 22. In the second lens unit 20, the second lens holding frame 22, the first adjustment frame 26, and the second adjustment frame 27 are arranged in this order from the image side in the optical axis direction.

[0015] Here, the holding method of the second adjustment lens 23, the first adjustment lens 24, and the reference lens 25 is thermal caulking. However, other holding methods such as adhesive fixing or pressing and fixing with a pressing member may be used, and the holding method is not limited. Also, the second adjustment lens 23, the first adjustment lens 24, and the reference lens 25 may be one or more lenses, and the configuration of the lenses is not limited.

[0016] The second lens holding frame 22 is engaged with the shaft-shaped guide bar 54 and is supported so as to be movable in the optical axis direction. Further, the second lens holding frame 22 is also engaged with the shaft-shaped guide bar 55, and rotation around the guide bar 54 is restricted. Further, the second lens holding frame 22 rotatably holds the two-group rack 28. The two-group rack 28 engages with the lead screw portion of the two-group drive unit 57 including an actuator such as a stepping motor. Therefore, when the lead screw portion rotates by the two-group drive unit 57, the second lens holding frame 22 moves in the optical axis direction together with the two-group rack 28.

[0017] Note that the second lens holding frame 22 is not limited to holding the two-group rack 28, and the first adjustment frame 26 or the second adjustment frame 27 may hold the two-group rack 28 and engage with the guide bars 54 and 55. Further, the detailed configurations of the second lens holding frame 22, the first adjustment frame 26, and the second adjustment frame 27, and the optical adjustment mechanism using them will be described later.

[0018] The third lens unit 30 includes a third lens group 31 and a third lens holding frame 32. The third lens group 31 is held by the third lens holding frame 32. The third lens holding frame 32 is engaged with the shaft-shaped guide bar 54 and is supported so as to be movable in the optical axis direction. Further, the third lens holding frame 32 is also engaged with the shaft-shaped guide bar 55, and rotation around the guide bar 54 is restricted. Further, the third lens holding frame 32 rotatably holds the three-group rack 33. The three-group rack 33 engages with the lead screw portion of the three-group drive unit 58 including an actuator such as a stepping motor. Therefore, when the lead screw portion rotates by the three-group drive unit 58, the third lens holding frame 32 moves in the optical axis direction together with the three-group rack 33.

[0019] The front housing member 50 and the rear housing member 51 function as the housing of the lens barrel 100. Specifically, the front housing member 50 and the rear housing member 51 accommodate the first lens unit 10, the second lens unit 20, and the third lens unit 30, and protect each lens unit from external shocks. The front housing member 50 and the rear housing member 51 are fixed together by screws or the like. The guide bars 52, 53, 54, 55 are supported by the front housing member 50 and the rear housing member 51. Also, the first group driving unit 56, the second group driving unit 57, and the third group driving unit 58 are fixed to the rear housing member 51 with screws or the like.

[0020] The imaging element unit 300 includes an imaging element 301 and an imaging substrate 302. The imaging element 301 is mounted on the imaging substrate 302. The imaging substrate 302 is fixed to the rear housing member 51 with screws or the like. Note that the form of fixing the imaging substrate 302 to the rear housing member 51 is not limited. For example, the imaging substrate 302 may be fixed to the rear housing member 51 via another member.

[0021] According to the imaging device 1 configured as described above, zooming and focusing are performed by moving the first lens unit 10, the second lens unit 20, and the third lens unit 30 in the optical axis direction of the imaging optical system in a predetermined positional relationship. An image light collected by the first lens unit 10, the second lens unit 20, and the third lens unit 30 forms an image on the imaging element 301, thereby enabling acquisition of a desired image.

[0022] Next, the decentration adjustment in the second lens unit 20 will be described. When performing decentration adjustment of the second lens unit 20, the optical axis O is directed so as to be in the vertical direction, and the second lens holding frame 22 is arranged on the lower side and the second adjustment frame 27 is arranged on the upper side. First, the decentration adjustment of the first adjustment lens 24 and the fixing method of the first adjustment frame 26 will be described. FIG. 4 is a cross-sectional view of the second lens unit 20. The left side in FIG. 4 is a cross-section passing through the first adhesive portion 223 and the second adhesive portion 263 described later. On the other hand, the right side in FIG. 4 is a cross-section passing through the screw 233 described later. FIG. 5 is a perspective view showing a state in which the first adjustment lens 24 is being eccentrically adjusted. FIG. 6 is a cross-sectional view of the second lens unit 20. The left side in FIG. 6 is a cross-section passing through the regulating member 62 arranged during the eccentric adjustment of the first adjustment lens 24. On the other hand, the right side in FIG. 6 is a cross-section of the first adhesive portion 223 and the second adhesive portion 263 after the eccentric adjustment and adhesion of the second adjustment lens 23.

[0023] When eccentrically adjusting the first adjustment lens 24, at least one first adjustment jig 61 such as a pin is used to press the side surface portion of the first adjustment frame 26. The first adjustment jig 61 may be configured to adsorb the first adjustment frame 26, for example. FIG. 5 shows an example in which the surrounding portion 225 (described later) of the first adjustment frame 26 is pressed and adjusted using the first adjustment jig 61 from three directions. As the first adjustment jig 61 moves forward and backward, the first adjustment frame 26 moves in a direction perpendicular to the optical axis with respect to the second lens holding frame 22. As the first adjustment frame 26 holding the first adjustment lens 24 moves, the first adjustment lens 24 moves to a desired position, and the eccentric adjustment is performed.

[0024] With the first lens unit 10 and the third lens unit 30 arranged, it is desirable to eccentrically adjust the first adjustment lens 24 so as to cancel out the total of minute eccentric displacements of each lens. Note that the eccentric adjustment may be performed so that the optical axis of the reference lens 25 held by the second lens holding frame 22 coincides with the optical axis of the first adjustment lens 24. In this case, minute eccentric displacements of each lens within the second lens unit 20 can be canceled out.

[0025] Here, the fastening portion 221 of the second lens holding frame 22 is formed close to the outer peripheral edge of the second lens holding frame 22. The fastening portion 221 extends in the optical axis direction, and a female screw portion 222 into which a screw 233 as a fastening member is screwed is formed. The fastening portions 221 are arranged at substantially equal intervals with a space therebetween on a circumference centered on the optical axis O (here, three). The first adjustment frame 26 has a fastening portion 261 formed in the vicinity of the outer peripheral edge of the first adjustment frame 26. The fastening portion 261 is an example of a first fixing portion and is a portion for fixing the first adjustment frame 26 to the second lens holding frame 22. A through hole 262 for inserting a screw 233 in the optical axis direction is formed in the fastening portion 261. The fastening portions 261 are arranged at substantially equal intervals with spaces therebetween on the circumference centered on the optical axis O (here, three). The second adjustment frame 27 has a fastening portion 271 formed in the vicinity of the outer peripheral edge of the second adjustment frame 27. The fastening portion 271 is an example of a second fixing portion and is a portion for fixing the second adjustment frame 27 to the first adjustment frame 26 or the second lens holding frame 22. A through hole 272 for inserting a screw 233 in the optical axis direction is formed in the fastening portion 271. The fastening portions 271 are arranged at substantially equal intervals with spaces therebetween on the circumference centered on the optical axis O (here, three).

[0026] The fastening portion 221 of the second lens holding frame 22, the fastening portion 261 of the first adjustment frame 26, and the fastening portion 271 of the second adjustment frame 27 are arranged such that a part of each overlaps with each other when viewed from the optical axis direction. Also, the female screw portion 222 of the second lens holding frame 22, the through hole 262 of the first adjustment frame 26, and the through hole 272 of the second adjustment frame 27 communicate with each other in the optical axis direction. Note that the inner diameter of the through hole 262 of the first adjustment frame 26 and the inner diameter of the through hole 272 of the second adjustment frame 27 are formed to be somewhat larger than the inner diameter of the female screw portion 222 of the second lens holding frame 22. Therefore, even if the first adjustment frame 26 is moved in a direction orthogonal to the optical axis with respect to the second lens holding frame 22, the screw 233 can be fastened to the female screw portion 222 without interfering with the through hole 262 and the through hole 272.

[0027] When adjusting the eccentricity of the first adjustment lens 24, an axial regulating member 62 such as a pin is used to restrict the movement of the second adjustment frame 27 with respect to the first adjustment frame 26, and the second adjustment frame 27 is also moved together with the first adjustment frame 26. The regulating member 62 is used as a so-called jig. Specifically, when adjusting the eccentricity of the first adjustment lens 24, before fastening the screw 233, as shown in FIG. 6, the regulating member 62 is inserted into the through hole 272 of the second adjustment frame 27 and the through hole 262 of the first adjustment frame 26. The regulating member 62 has a length that does not contact the female screw portion 222, while having a shaft diameter that fits with the through hole 272 and the through hole 262. That is, the shaft diameter of the regulating member 62 is larger than the shaft diameter of the screw 233. As shown in FIG. 5, by inserting a plurality of regulating members 62 into the through hole 272 and the through hole 262 respectively, the eccentricity adjustment of the first adjustment lens 24 can be performed in a state where the optical axis of the first adjustment lens 24 and the optical axis of the second adjustment lens 23 are substantially coincident. The first adjustment lens 24 and the second adjustment lens 23 are each responsible for improving different optical performances. However, if the second adjustment lens 23 moves freely during the eccentricity adjustment of the first adjustment lens 24, the deviation of the optical axis cannot be appropriately corrected. Therefore, by moving the second adjustment frame 27 together with the first adjustment frame 26, high optical performance can be achieved. In this embodiment, the inner diameter of the through hole 272 and the inner diameter of the through hole 262 are the same. However, when using a stepped regulating member 62, the inner diameter of the through hole 272 may be larger than the inner diameter of the through hole 262.

[0028] When the eccentricity adjustment of the first adjustment lens 24 is completed, the first adjustment frame 26 is fixed to the second lens holding frame 22. To fix the first adjustment frame 26 to the second lens holding frame 22, for example, adhesion is used. In the second lens unit 20, a first adhesive portion 223 is formed close to the outer peripheral edge of the first adjustment frame 26. The first adhesive portion 223 is an example of the first fixing portion and is a part for fixing the first adjustment frame 26 to the second lens holding frame 22. The first adhesive portions 223 are arranged at substantially equal intervals with a space on the circumference centered on the optical axis O (here, three).

[0029] Here, the first adhesive portion 223 is composed of a part of the second lens holding frame 22 and a part of the first adjustment frame 26. As shown in FIGS. 4 and 6, the first adhesive portion 223 is formed in a concave shape that is recessed toward the image side in the optical axis direction by a bottom surface 224a perpendicular to the optical axis O, and side surfaces 224b, 224c (see FIG. 4), 224d (see FIG. 6) extending in the optical axis direction from the bottom surface 224a. In the present embodiment, the bottom surface 224a is composed of a part of the second lens holding frame 22. Further, the side surface 224b is located away from the optical axis O, and the second lens holding frame 22 extends from the bottom surface 224a toward the object side in the optical axis direction. The side surface 224c is located on the optical axis O side and is composed of a part of the first adjustment frame 26. Further, as shown in FIG. 6, a pair of opposing side surfaces 224d are formed integrally with the first adjustment frame 26 and are composed of a substantially C-shaped surrounding portion 225 when viewed from the optical axis direction. That is, among the side surfaces 224b to 224d of the first adhesive portion 223 of the present embodiment, except for the side surface 224b away from the optical axis O side, the first adjustment frame 26 is composed.

[0030] By filling the first adhesive portion 223 with the adhesive (AH1), the first adjustment frame 26 is fixed to the second lens holding frame 22 via the adhesive (AH1). After the first adjustment frame 26 is fixed to the second lens holding frame 22, the first alignment jig 61 and the regulating member 62 are removed, and the eccentricity adjustment of the first adjustment lens 24 and the fixing (temporary fixing) of the first adjustment frame 26 are completed.

[0031] Next, a method for adjusting the eccentricity of the second adjustment lens 23 and fixing the second adjustment frame 27 will be described. FIG. 7 is a perspective view showing a state in which the eccentricity of the second adjustment lens 23 is being adjusted. When adjusting the eccentricity of the second adjustment lens 23, at least one second alignment jig 63 such as a pin is used to press the side surface portion of the second adjustment frame 27. The second alignment jig 63 may be configured to adsorb the second adjustment frame 27, for example. FIG. 7 shows an example in which the outer peripheral side surface of the second adjustment frame 27 is pressed and adjusted using the second alignment jig 63 from three directions. As the second alignment jig 63 moves forward and backward, the second adjustment frame 27 moves in a direction perpendicular to the optical axis with respect to the second lens holding frame 22 and the first adjustment frame 26. As the second adjustment frame 27 holding the second adjustment lens 23 moves, the second adjustment lens 23 moves to a desired position, and eccentricity adjustment is performed.

[0032] With the first lens unit 10 and the third lens unit 30 arranged, it is desirable to perform eccentricity adjustment on the second adjustment lens 23 so as to cancel out the sum of minute eccentricity displacements of each lens. Since the eccentricity adjustment of the first adjustment lens 24 has already been performed, eccentricity adjustment may be performed so that the optical axes of the first adjustment lens 24 and the reference lens 25, whose optical axes coincide, coincide with the optical axis of the second adjustment lens 23. In this case, minute eccentricity displacements of each lens within the second lens unit 20 can be canceled out.

[0033] When the eccentricity adjustment of the second adjustment lens 23 is completed, the second adjustment frame 27 is fixed to the first adjustment frame 26. For example, adhesion is used to fix the second adjustment frame 27 to the first adjustment frame 26. In the second lens unit 20, a second adhesive portion 263 is formed in the vicinity of the outer peripheral edge of the second adjustment frame 27. The second adhesive portion 263 is an example of the second fixing portion and is a portion for fixing the second adjustment frame 27 to the second lens holding frame 22 or the first adjustment frame 26. The second adhesive portions 263 are arranged at substantially equal intervals with a gap on the circumference centered on the optical axis O (here, three). The second adhesive portion 263 and the above-described first adhesive portion 223 are arranged so that a part of each overlaps when viewed from the optical axis direction.

[0034] Note that the first adhesive portion 223 and the second adhesive portion 263, and the above-described fastening portions 261, 271, 221 are arranged so that their phases do not overlap on the circumference. Also, the first adhesive portion 223 and the second adhesive portion 263, and the fastening portions 261, 271, 221 are arranged adjacent to each other when viewed from the optical axis direction. Further, the first adhesive portion 223, the second adhesive portion 263, the fastening portions 261, 271, 221, and the guide bars 52, 53, 54, 55 are arranged so as not to overlap when viewed from the optical axis direction.

[0035] Here, the second adhesive portion 263 is composed of a part of the adhesive (AH1) filled in the first adhesive portion 223, a part of the second adjustment frame 27, and a part of the first adjustment frame 26. As shown in FIGS. 4 and 6, the second adhesive portion 263 is formed in a concave shape that is recessed toward the image side in the optical axis direction by a bottom surface 264a perpendicular to the optical axis O and side surfaces 264b, 264c (see FIG. 4), 264d (see FIG. 6) extending in the optical axis direction from the bottom surface 264a. In the present embodiment, the bottom surface 264a is composed of a part of the adhesive (AH1) filled in the first adhesive portion 223. Further, the side surface 264b is located away from the optical axis O and is composed of an enclosing portion 225 integrally formed with the first adjustment frame 26. Also, as shown in FIG. 6, a pair of opposing side surfaces 264d are composed of the enclosing portion 225. The pair of side surfaces 264d are continuously formed so as to extend from the pair of side surfaces 224d described above. Also, the pair of side surfaces 264d and the pair of side surfaces 224d are integrally formed by the same member, specifically, the first adjustment frame 26. Therefore, in the second adhesive portion 263 of the present embodiment, except for the side surface 264c located on the optical axis O side among the side surfaces 264b to 264d, it is composed of a part of the first adjustment frame 26.

[0036] By filling the second adhesive portion 263 with the adhesive (AH2), the second adjustment frame 27 is fixed to the first adjustment frame 26 via the adhesive (AH2). After the second adjustment frame 27 is fixed to the first adjustment frame 26, by removing the second adjustment jig 63, the eccentricity adjustment of the first adjustment lens 24 and the fixing (temporary fixing) of the first adjustment frame 26 are completed.

[0037] Finally, the first adjustment frame 26 and the second adjustment frame 27 are fixed to the second lens holding frame 22 using screws 233 as common fastening members. That is, the screw 233 is inserted in the optical axis direction through the through hole 272 of the fastening portion 271 of the second adjustment frame 27 and the through hole 262 of the fastening portion 261 of the first adjustment frame 26. By fastening the screw 233 inserted through the through hole 272 and the through hole 262 to the female screw portion 222 of the fastening portion 221 of the second lens holding frame 22 from the object side, the first adjustment frame 26 and the second adjustment frame 27 are fixed to the second lens holding frame 22. In this way, by fastening using the screw 233, it is possible to prevent fluctuations of the first adjustment frame 26 or the second adjustment frame 27 due to the expansion and contraction of the adhesive, and it is possible to improve the reliability of the optical performance.

[0038] Here, as shown in FIG. 6, the side surface 264d of the second adhesive portion 263 is formed by extending the side surface 224d of the first adhesive portion 223 in the optical axis direction. That is, the side surface 264d of the second adhesive portion 263 and the side surface 224d of the first adhesive portion 223 are common continuous surfaces. By configuring in this way, when viewed from the optical axis direction, since the first adhesive portion 223 and the second adhesive portion 263 have a completely overlapping portion, it is possible to achieve space saving of the fixing structure. Further, when filling with an adhesive having a low viscosity, the side surface 264d of the continuous second adhesive portion 263 and the side surface 224d of the first adhesive portion 223 serve as guides, and the adhesive can be filled into the first adhesive portion 223.

[0039] As described above, according to the present embodiment, the first adjustment frame 26 that can be adjusted in a direction orthogonal to the optical axis with respect to the second lens holding frame 22 and the second adjustment frame 27 that can be adjusted in a direction orthogonal to the optical axis with respect to the second lens holding frame 22 are arranged on the object side in the optical axis direction with respect to the second lens holding frame 22. On the image side in the optical axis direction, various components for imaging or driving the lens are arranged. By arranging the first adjustment frame 26 and the second adjustment frame 27 on the object side, it is possible to arrange them so as to suppress interference between the adjustment mechanism and the various components, and thus it is possible to suppress an increase in the size of the lens unit and the lens barrel.

[0040] Further, according to the present embodiment, the first adhesive portion 223 and the second adhesive portion 263 are arranged such that a part of each of them overlaps with the other when viewed from the optical axis direction. Also, the fastening portion 261 and the fastening portion 271 are arranged such that a part of each of them overlaps with the other when viewed from the optical axis direction. Therefore, structures related to lens driving such as the rack holding structure and the guide bar engagement structure can be arranged in a space where the first adhesive portion 223, the second adhesive portion 263, the fastening portion 261, and the fastening portion 271 are not arranged when viewed from the optical axis direction. For this reason, compared with the case of holding the lens using a pressing ring or the like as in the prior art, since the structures related to lens driving can be arranged closer to the optical axis O, it is possible to suppress an increase in the size of the lens unit and the lens barrel.

[0041] Further, according to the present embodiment, the first adhesive portion 223 and the second adhesive portion 263 are arranged such that a part of each of them overlaps with the other when viewed from the optical axis direction. Therefore, in the direction perpendicular to the optical axis O, the operation of adhering the first adjustment frame 26 and the second adjustment frame 27 can be performed at substantially the same position.

[0042] Also, according to the present embodiment, when assembling the second lens unit 20, the second lens holding frame 22, the first adjustment frame 26, and the second adjustment frame 27 are arranged in this order from the lower side in the direction of gravity. Therefore, when adjusting the first adjustment frame 26 and the second adjustment frame 27 with respect to the second lens holding frame 22, adhering them with an adhesive, or fastening them with screws 233, it can be performed from the upper side in the direction of gravity. For this reason, it is possible to make the configuration such that the first adjustment frame 26 and the second adjustment frame 27 are easy to adjust and easy to assemble.

[0043] Further, according to the present embodiment, when adjusting the eccentricity of the first adjustment lens 24, by inserting the restricting member 62 into the through hole 272 of the second adjustment frame 27 and the through hole 262 of the first adjustment frame 26, the second adjustment frame 27 can be moved together with the first adjustment frame 26. Further, the through holes 262 and 272 into which the restricting member 62 is inserted also serve as holes for fastening the second adjustment frame 27 and the first adjustment frame 26 to the second lens holding frame 22. Therefore, since there is no need to provide a new structure for inserting the restricting member 62, space can be saved in the second lens unit 20. When a new structure is provided for inserting the restricting member 62, a configuration for blocking the holes penetrating the first adjustment frame 26 and the second adjustment frame 27 to prevent stray light is required, but there is no need to prevent stray light either.

[0044] <Modification Example 1> FIG. 8 is a perspective view showing a state in which the first adjustment lens 24 is being adjusted for eccentricity according to Modification Example 1. In this modification, when adjusting the eccentricity of the first adjustment lens 24, the outer peripheral side surface of the second adjustment frame 27 is pressed and adjusted using the second adjustment jig 63 instead of the first adjustment jig 61. By using the restricting member 62, since the first adjustment frame 26 can be moved as the second adjustment frame 27 moves, the second adjustment jig 63 may be advanced and retracted to adjust the first adjustment frame 26, and the second adjustment frame 27 may be moved in a direction perpendicular to the optical axis.

[0045] <Modification Example 2> FIG. 9 is a cross-sectional perspective view showing the configurations of the first adhesive portion 226 and the second adhesive portion 266 according to Modification Example 2. The first adhesive portion 226 is formed in a concave shape that is recessed toward the image side in the optical axis direction by a bottom surface 227a perpendicular to the optical axis O and side surfaces 227b and 227c extending from the bottom surface 227a in the optical axis direction. The bottom surface 227a is constituted by a part of the second lens holding frame 22. The side surface 227b away from the optical axis O is constituted by a part of the second lens holding frame 22, and the side surface 227c on the optical axis O side is constituted by a part of the first adjustment frame 26. Also, a pair of side surfaces (not shown) are constituted by a part of the second lens holding frame 22. Therefore, the side surfaces other than the side surface 227c on the optical axis O side are constituted by a part of the second lens holding frame 22.

[0046] The second bonding portion 266 is formed in a concave shape that is recessed toward the image side in the optical axis direction by a bottom surface 267a perpendicular to the optical axis O, and side surfaces 267b and 267c extending from the bottom surface 267a in the optical axis direction. The bottom surface 267a is constituted by a part of the adhesive (AH1) filled in the first bonding portion 226. The side surface 267b away from the optical axis O is constituted by a part of the second lens holding frame 22, and the side surface 267c on the optical axis O side is constituted by a part of the second adjustment frame 27. Also, a pair of side surfaces (not shown) are constituted by a part of the second lens holding frame 22. Therefore, the side surfaces other than the side surface 227c on the optical axis O side are constituted by a part of the second lens holding frame 22.

[0047] In this modification, the side surfaces other than the side surface 267c of the second bonding portion 266 are continuously formed so as to extend from the side surfaces other than the side surface 227c of the first bonding portion 226. Also, the side surfaces other than the side surface 267c of the second bonding portion 266 and the side surfaces other than the side surface 227c of the first bonding portion 226 are integrally constituted by the same member, specifically, the second lens holding frame 22. Therefore, since it is possible to bond to a common surface between the first bonding portion 226 and the second bonding portion 266, the same effects as those of the first embodiment can be obtained.

[0048] <Modification 3> FIG. 10 is a cross-sectional perspective view showing the configurations of the first bonding portion 228 and the second bonding portion 268 according to Modification 3. The first bonding portion 228 is formed in a concave shape that is recessed toward the image side in the optical axis direction by a bottom surface 229a perpendicular to the optical axis O, and side surfaces 229b and 229c extending from the bottom surface 229a in the optical axis direction. The bottom surface 229a is constituted by a part of the second lens holding frame 22. The side surfaces 229b and 229c and a pair of side surfaces (not shown) are constituted by a part of the first adjustment frame 26.

[0049] The second bonding portion 268 is formed in a concave shape that is recessed toward the image side in the optical axis direction by a bottom surface 269a perpendicular to the optical axis O and side surfaces 269b and 269c extending in the optical axis direction from the bottom surface 269a. The bottom surface 269a is constituted by a part of the adhesive (AH1) filled in the first bonding portion 228. The side surface 269c on the optical axis O side is constituted by a part of the second adjustment frame 27, and the side surfaces other than the side surface 269c on the optical axis O side are constituted by a part of the first adjustment frame 26.

[0050] In this modification, the side surfaces other than the side surface 269c of the second bonding portion 268 are continuously formed so as to extend from the side surfaces other than the side surface 229c of the first bonding portion 228. Further, the side surfaces other than the side surface 269c of the second bonding portion 268 and the side surfaces other than the side surface 229c of the first bonding portion 228 are integrally constituted by the same member, specifically, the first adjustment frame 26. Therefore, since it is possible to bond to the common surface between the first bonding portion 228 and the second bonding portion 268, the same effects as those of the first embodiment can be obtained.

[0051] As described above, the preferred embodiments of the present invention have been described. However, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist thereof. Also, as long as the configuration takes into account the design function, it is not limited thereto.

[0052] In the above-described embodiment, the case where the first adjustment frame 26 is fixed to the second lens holding frame 22 via an adhesive and the second adjustment frame 27 is fixed to the first adjustment frame 26 or the second lens holding frame 22 via an adhesive has been described. However, the present invention is not limited to this case. For example, the first adjustment frame 26 and the second adjustment frame 27 may be collectively fixed to the second lens holding frame 22 using screws 233 as fastening members. In this case, after the eccentricity adjustment of the first adjustment lens 24, without removing the first adjustment jig 61, the eccentricity adjustment of the second adjustment lens 23 is performed, and the screw 233 is fastened to the fastening portion 221 of the second lens holding frame 22. After the screw 233 is fastened, the first adjustment jig 61 and the second adjustment jig 63 are removed. Further, the first adjustment frame 26 and the second adjustment frame 27 may be fixed to the second lens holding frame 22 only with an adhesive without fastening with the screw 233.

[0053] In the above-described embodiment, the female screw portion 222 is not limited to the case where the screw is formed in advance, and the screw may be formed by screwing in the screw 233. Further, the fastening member is not limited to the screw 233, and may be a rivet or the like.

[0054] Further, the disclosure of the present embodiment includes the following configurations and the like. (Configuration 1) A lens unit having a plurality of lenses, a holding frame that holds a first lens among the plurality of lenses, a first adjustment frame that holds a first adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, a second adjustment frame that holds a second adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, and the first adjustment frame and the second adjustment frame are arranged on the object side in the optical axis direction with respect to the holding frame. A lens unit characterized by this. (Configuration 2) a first fixing portion for fixing the first adjustment frame to the holding frame, a second fixing portion for fixing the second adjustment frame to the holding frame or the first adjustment frame. The lens unit according to Configuration 1, characterized by having this. (Configuration 3) The first fixing portion and the second fixing portion overlap at least partially with each other when viewed from the optical axis direction. The lens unit according to Configuration 2, characterized by this. (Configuration 4) The first fixing portion and the second fixing portion are each filled with an adhesive. The lens unit according to Configuration 2 or 3, characterized by this. (Configuration 5) The first fixing portion and the second fixing portion are each formed in a concave shape that is recessed toward the image side in the optical axis direction, a side surface of a part of the first fixing portion and a side surface of a part of the second fixing portion are continuous and integrally formed. The lens unit according to Configuration 4, characterized by this. (Configuration 6) The first fixing portion and the second fixing portion are each formed in a concave shape that depresses toward the image side in the optical axis direction, The lens unit according to Configuration 4 or 5, wherein a bottom surface of the second fixing portion is constituted by an adhesive filled in the first fixing portion. (Configuration 7) The first fixing portion and the second fixing portion have through holes through which fastening members are inserted in the optical axis direction, The lens unit according to Configuration 2 or 3, wherein the fastening member inserted through the through hole of the first fixing portion and the through hole of the second fixing portion is fastened to the holding frame. (Configuration 8) The lens unit according to Configuration 7, wherein an inner diameter of the through hole of the second fixing portion is the same as or larger than an inner diameter of the through hole of the first fixing portion. (Configuration 9) A first bonding portion for bonding the first adjustment frame to the holding frame using an adhesive, A second bonding portion for bonding the second adjustment frame to the holding frame or the first adjustment frame using an adhesive, A first fastening portion for fastening the first adjustment frame to the holding frame using a fastening member, The lens unit according to Configuration 1, further comprising a second fastening portion for fastening the second adjustment frame to the holding frame or the first adjustment frame using the fastening member. (Configuration 10) The first bonding portion and the second bonding portion at least partially overlap each other when viewed from the optical axis direction, The first fastening portion and the second fastening portion at least partially overlap each other when viewed from the optical axis direction, The lens unit according to Configuration 9, wherein the first bonding portion and the second bonding portion, and the first fastening portion and the second fastening portion are arranged adjacent to each other when viewed from the optical axis direction. (Configuration 11) The lens unit according to any one of Configurations 1 to 10, wherein the holding frame is movable in the optical axis direction by a guide bar. (Configuration 12) A lens unit according to any one of Configurations 2 to 8, and a plurality of guide bars engaged with the holding frame, wherein the plurality of guide bars, the first fixing portion, and the second fixing portion are arranged so as not to overlap when viewed from the optical axis direction. A lens barrel characterized by this. (Method 1) A method for adjusting a lens unit having a plurality of lenses, comprising: The lens unit includes a holding frame that holds a first lens among the plurality of lenses, a first adjustment frame that holds a first adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, a second adjustment frame that holds a second adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, and the first adjustment frame and the second adjustment frame are arranged on the object side in the optical axis direction with respect to the holding frame, When adjusting the first adjustment frame in a direction orthogonal to the optical axis with respect to the holding frame, the adjustment is performed while restricting the movement of the second adjustment frame with respect to the first adjustment frame. A method for adjusting a lens unit, characterized by this. (Method 2) The first adjustment frame has a first fastening portion for fastening the first adjustment frame to the holding frame, The second adjustment frame has a second fastening portion for fastening the second adjustment frame to the holding frame or the first adjustment frame, By inserting a restricting member into the through hole of the first fastening portion and the through hole of the second fastening portion, the movement of the second adjustment frame with respect to the first adjustment frame is restricted. The method for adjusting a lens unit according to Method 1, characterized by this. (Method 3) A fastening member having a shaft diameter smaller than the shaft diameter of the regulating member is inserted into the through holes of the first fastening portion and the through holes of the second fastening portion, and the fastening member is fastened to the holding frame. The method for adjusting the lens unit according to Method 2, characterized in that.

Explanation of symbols

[0055] 20: Second lens unit 22: Second lens holding frame 23: Second adjustment lens 24: First adjustment lens 25: Reference lens 26: First adjustment frame 27: Second adjustment frame

Claims

1. A lens unit having a plurality of lenses, a holding frame for holding a first lens among the plurality of lenses, a first adjustment frame for holding a first adjustment lens among the plurality of lenses and being adjustable in a direction orthogonal to the optical axis with respect to the holding frame, a second adjustment frame for holding a second adjustment lens among the plurality of lenses and being adjustable in a direction orthogonal to the optical axis with respect to the holding frame, and having the second adjustment frame, The first adjustment frame and the second adjustment frame are arranged on the object side in the optical axis direction with respect to the holding frame. A lens unit characterized by this.

2. a first fixing portion for fixing the first adjustment frame to the holding frame, a second fixing portion for fixing the second adjustment frame to the holding frame or the first adjustment frame, and the lens unit according to claim 1, characterized by having the second fixing portion.

3. The first fixing portion and the second fixing portion overlap at least partially with each other when viewed from the optical axis direction. The lens unit according to claim 2, characterized by this.

4. The first fixing portion and the second fixing portion are each filled with an adhesive. The lens unit according to claim 2 or 3, characterized by this.

5. The first fixing portion and the second fixing portion are each formed in a concave shape that is recessed toward the image side in the optical axis direction, A part of the side surface of the first fixing portion and a part of the side surface of the second fixing portion are continuous and integrally formed. The lens unit according to claim 4, characterized by this.

6. The first fixing portion and the second fixing portion are each formed in a concave shape that is recessed toward the image side in the optical axis direction, The bottom surface of the second fixing portion is constituted by the adhesive filled in the first fixing portion. The lens unit according to claim 4, characterized by this.

7. The first fixing portion and the second fixing portion have through holes through which the fastening member is inserted in the optical axis direction. The lens unit according to claim 2 or 3, wherein the fastening member inserted through the through hole of the first fixing portion and the through hole of the second fixing portion is fastened to the holding frame.

8. The lens unit according to claim 7, wherein an inner diameter of the through hole of the second fixing portion is the same as or larger than an inner diameter of the through hole of the first fixing portion.

9. A first bonding portion for bonding the first adjustment frame to the holding frame using an adhesive, A second bonding portion for bonding the second adjustment frame to the holding frame or the first adjustment frame using an adhesive, A first fastening portion for fastening the first adjustment frame to the holding frame using a fastening member, The lens unit according to claim 1, further comprising a second fastening portion for fastening the second adjustment frame to the holding frame or the first adjustment frame using the fastening member.

10. The first bonding portion and the second bonding portion at least partially overlap each other when viewed in the optical axis direction. The first fastening portion and the second fastening portion at least partially overlap each other when viewed in the optical axis direction. The lens unit according to claim 9, wherein the first bonding portion and the second bonding portion, and the first fastening portion and the second fastening portion are arranged adjacent to each other when viewed in the optical axis direction.

11. The lens unit according to claim 1 or 2, wherein the holding frame is movable in the optical axis direction by a guide bar.

12. The lens unit according to claim 2, and a plurality of guide bars engaged with the holding frame. The plurality of guide bars, the first fixing portion, and the second fixing portion are arranged so as not to overlap when viewed from the optical axis direction. A lens barrel characterized by this.

13. A method for adjusting a lens unit having a plurality of lenses, The lens unit is A holding frame that holds a first lens among the plurality of lenses, A first adjustment frame that holds a first adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, A second adjustment frame that holds a second adjustment lens among the plurality of lenses and is adjustable in a direction orthogonal to the optical axis with respect to the holding frame, and has The first adjustment frame and the second adjustment frame are arranged on the object side in the optical axis direction with respect to the holding frame, When adjusting the first adjustment frame in a direction orthogonal to the optical axis with respect to the holding frame, it is characterized in that the adjustment is performed while restricting the movement of the second adjustment frame with respect to the first adjustment frame. A method for adjusting a lens unit.

14. The first adjustment frame has a first fastening portion for fastening the first adjustment frame to the holding frame, The second adjustment frame has a second fastening portion for fastening the second adjustment frame to the holding frame or the first adjustment frame, By inserting a restricting member into the through holes of the first fastening portion and the through holes of the second fastening portion, the movement of the second adjustment frame with respect to the first adjustment frame is restricted. The method for adjusting a lens unit according to claim 13.

15. A fastening member having a shaft diameter smaller than the shaft diameter of the restricting member is inserted into the through holes of the first fastening portion and the through holes of the second fastening portion, and the fastening member is fastened to the holding frame. The method for adjusting a lens unit according to claim 14.

Images