Lens barrel and alignment method

Abstract

To provide a lens barrel that can be disassembled easily and can reutilize a base member and a lens holding member, and can reliably fix the lens holding member after adjustment for moving the lens holding member in parallel within a plane orthogonal to a light axis.SOLUTION: In a lens barrel having a lens holding member for holding a lens, a base member fixed to the lens holding member by a fixing member, and an adjustment member for adjusting relative positions of the lens holding member and the base member, the lens holding member has a fixing hole, the fixing member has an eccentricity fixation shaft fixed to the fixing hole, an elastic member having a through hole into which the eccentricity fixation shaft is inserted, and an eccentricity fixation collar that has a through hole into which the eccentricity fixation shaft is inserted and is fitted to the base member, the elastic member is clamped by the lens holding member and the eccentricity fixation collar, and the lens holding member and the base member are fixed by filling an adhesive in an adhesion portion formed from the eccentricity fixation shaft, the elastic member, and the eccentricity fixation collar.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a lens barrel and an alignment method. In particular, it relates to a method of fixing a lens after adjusting it to move parallel within a plane orthogonal to the optical axis.

Background Art

[0002] Conventionally, in a lens barrel used in a digital still camera or the like, an alignment operation is performed in the manufacturing process to suppress deterioration of optical performance.

[0003] The alignment operation is performed by attaching the lens barrel to an alignment jig and adjusting the position of a lens holding member held by a base member while inspecting the resolution performance. At this time, it is necessary to fix the base member and the lens holding member at a relative position that satisfies the required performance.

[0004] In particular, in a lens barrel with a heavy lens holding member, it is conceivable that the relative position after adjustment will easily shift due to impact or movement. Therefore, in a lens barrel with a heavy lens holding member, it is necessary to strengthen the fixing especially.

[0005] Patent Document 1 discloses an eccentricity adjustment structure that improves the fixing accuracy of a lens after eccentricity adjustment and enables disassembly and reassembly of lens component parts when performing eccentricity adjustment again.

[0006] Further, Patent Document 2 discloses a lens barrel having a structure that is easy to disassemble, the base member and the lens chamber can be reused, and is applicable to an alignment mechanism in the falling direction of the lens chamber.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

[0008] However, in the eccentricity adjustment mechanism described in Patent Document 1, adhesive is injected directly into the pin fixing hole, which presents problems such as the adhesive not being completely removed from the pin fixing hole during disassembly and adjustment, leaving behind debris, and poor workability. In addition, there is a risk that adhesive may flow into the gap between the lens frame and the base barrel, making disassembly difficult.

[0009] In the lens barrel described in Patent Document 2, there is no problem when adjusting the tilt direction of the lens chamber, but when adjusting it to move parallel within a plane perpendicular to the optical axis, the gap between the inner surface of the eccentric fixing collar and the flange portion of the eccentric fixing shaft changes depending on the amount of adjustment. As a result, adhesive flows into the gap, which is undesirable. To eliminate the occurrence of the gap, it is conceivable to add a step of pushing the eccentric fixing collar from the outer diameter side of the lens barrel after adjustment, but since the eccentric fixing collar is fitted to the lens holding member, there is a risk that the adjustment will be misaligned if strong force is applied to push it in. Furthermore, although the disclosure describes adjustment to move parallel within a plane perpendicular to the optical axis, the configuration is applicable when the mounting direction is the same as the optical axis, and is difficult to apply to configurations where the lens is positioned in the direction of the tool work.

[0010] The present invention has been made in view of the above problems, and aims to provide a lens barrel that is easy to disassemble, allows for the reuse of the base member and lens holding member, and enables secure fixing after adjustment by moving the lens holding member parallel in a plane perpendicular to the optical axis. [Means for solving the problem]

[0011] The lens barrel of the present invention comprises a lens holding member for holding a lens, a base member fixed to the lens holding member by a fixing member, and an adjustment member for adjusting the relative position between the lens holding member and the base member, wherein the lens holding member has a fixing hole. The base member has placement holes, The fixing member includes an eccentric fixing shaft fixed in a fixing hole, an elastic member having a through hole through which the eccentric fixing shaft is inserted, and a through hole through which the eccentric fixing shaft is inserted Placement hole The lens holder has an eccentric fixing collar fitted to it, and the elastic member is sandwiched between the lens holder and the eccentric fixing collar, and the lens holder and the base member are fixed by filling the adhesive portion formed by the eccentric fixing shaft, the elastic member and the eccentric fixing collar with adhesive.

[0012] Furthermore, the alignment method of the present invention comprises a lens holding member having a fixing hole for holding a lens, a base member having a positioning hole and fixed to the lens holding member by the fixing member, and an eccentric roller that adjusts the position of the lens holding member and the base member by rotation, wherein the fixing member comprises an eccentric fixing shaft fixed to the fixing hole, an elastic member having a through hole through which the eccentric fixing shaft is inserted, and an eccentric fixing collar having a through hole through which the eccentric fixing shaft is inserted, and the elastic member is sandwiched between the lens holding member and the eccentric fixing collar, and the method of alignment of the lens barrel is The process involves fixing the eccentric fixing shaft into the fixing hole, and inserting the elastic member onto the eccentric fixing shaft. The process involves fitting the eccentric fixing collar into the placement hole and rotating the eccentric roller provided on the outer circumference of the lens holding member to move the lens holding member. Lens The lens holding member is aligned by the following steps: an adjustment step of moving it parallel to the optical axis in a plane perpendicular to the optical axis, and a step of filling the adhesive portion formed by the eccentric fixing shaft, eccentric fixing collar, and elastic member with adhesive so as to fix the lens holding member and the base member in the predetermined position after adjustment. [Effects of the Invention]

[0013] According to the lens barrel of the present invention, disassembly is easy, the base member and lens holding member can be reused, and the lens holding member can be securely fixed after adjustment by moving it parallel in a plane perpendicular to the optical axis.

Brief Description of the Drawings

[0014] [Figure 1] Perspective view of the main part of the lens barrel 10 according to an embodiment of the present invention [Figure 2] Exploded perspective view of the main part of the lens barrel 10 according to an embodiment of the present invention [Figure 3] Perspective view of the shift alignment roller 41 and tilt alignment roller 42 which are adjustment members according to an embodiment of the present invention [Figure 4] Perspective view of the fixing member 50 according to an embodiment of the present invention [Figure 5] Perspective view of the eccentric fixing shaft 70 [Figure 6] Perspective view of the elastic member 80 [Figure 7] Perspective view of the eccentric fixing collar 90 [Figure 8] Cross-sectional view of the fixing member 50 according to an embodiment of the present invention [Figure 9] Enlarged view of the fixing member arrangement hole 21 in FIG. 2 [Figure 10] Diagram for explaining the eccentric fixing shaft 70 having the flange portion 74 [Figure 11] Perspective view of the fixing member 50 provided with the eccentric fixing shaft 70 having the flange portion 74 [Figure 12] Cross-sectional view of the fixing member 50 provided with the eccentric fixing shaft 70 having the flange portion 74

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the present invention is not limited by this embodiment. Also, in this application, screw threads will not be depicted for simplicity's sake.

[0016] Figure 1 is a perspective view of the main part of a lens barrel 10 according to an embodiment of the present invention, and Figure 2 is an exploded perspective view of the main part of a lens barrel 10 according to an embodiment of the present invention. Hereinafter, the various components of the lens barrel 10 will be described using Figures 1 and 2. The lens barrel 10 is replaceable and can be attached to an imaging device, and has an optical axis at its center. In this invention, the optical axis side of the lens barrel 10 will be referred to as the inner circumference side of the lens barrel, and the opposite side will be referred to as the outer circumference side of the lens barrel.

[0017] The lens barrel 10 includes a fixed frame 20 which is a base member, a lens holding frame 30 which is a lens holding member, a shift adjustment roller 41 and a tilt adjustment roller 42 which are adjustment members for adjusting the relative position between the fixed frame 20 and the lens holding frame 30, and a fixing member 50 which fixes the fixed frame 20 and the lens holding frame 30.

[0018] The fixed frame 20 is a lens group holding tube for centering the lens barrel 10. The fixed frame 20 has multiple fixed parts 24 and is fixed to the lens barrel 10 with screws. The fixed frame 20 is also provided with a fixed member placement hole 21 into which the eccentric fixing collar 90 of the fixed member 50 is fitted, a shift centering roller placement hole 22 into which the shift centering roller 41 is fitted, and a tilt centering roller placement hole 23 into which the tilt centering roller 42 is fitted.

[0019] The lens holding frame 30 is a component that holds the lens group 35. The lens barrel 10 is aligned by adjusting the lens holding frame 30 to move parallel to the optical axis in a plane perpendicular to the optical axis (hereinafter referred to as shift adjustment) or by adjusting the lens holding frame 30 to tilt relative to the optical axis (hereinafter referred to as tilt adjustment). The lens holding frame 30 is also provided with a fixing hole 31 into which the fitting portion 71 of the eccentric fixing shaft 70 of the fixing member 50 fits, a screw hole portion f32, a screw hole portion s33 for fixing the shift alignment roller 41, and a screw hole portion t34 for fixing the tilt alignment roller 42.

[0020] Next, the shift adjustment roller 41 and tilt adjustment roller 42, which are adjustment members, will be described using Figure 3. The shift adjustment roller 41 and tilt adjustment roller 42 are eccentric cylindrical members that are fitted into the shift adjustment roller placement hole 22 and the tilt adjustment roller placement hole 23 provided in the fixed frame 20, respectively. The shift adjustment roller 41 and tilt adjustment roller 42 are fixed to the screw holes s33 and t34 of the lens holding frame 30 by mounting screws 44. The relative position between the fixed frame 20 and the lens holding frame 30 is adjusted by rotating the shift adjustment roller 41 and the tilt adjustment roller 42, according to the set eccentricity amount for each. The shift adjustment roller 41 and the tilt adjustment roller 42 are also provided with notches 43 for engaging a tool when rotating them.

[0021] Next, the fixing members will be described using Figures 4, 5, 6, 7, and 8. Figure 4 is a perspective view of a fixing member 50 according to an embodiment of the present invention, Figure 5 is a perspective view of an eccentric fixing shaft 70 of the fixing member 50, Figure 6 is a perspective view of an elastic member 80 of the fixing member 50, Figure 7 is a perspective view of an eccentric fixing collar 90 of the fixing member 50, and Figure 8 is a cross-sectional view of a fixing member 50 according to an embodiment of the present invention.

[0022] The fixing member 50 includes an eccentric fixing shaft 70 having a fitting portion 71, an elastic member 80, and an eccentric fixing collar 90. The fixing frame 20 and the lens holding frame 30 are fixed by the shift adjustment roller 41, the tilt adjustment roller 42, and the respective mounting screws 44. However, since each adjustment roller is rotatable for adjustment, there is a risk that the position of the shift adjustment roller 41 or the tilt adjustment roller 42 may shift when subjected to a strong impact. Therefore, by providing the fixing member 50, the adjusted position is fixed at a point other than each adjustment roller, thereby preventing misalignment of the shift adjustment roller 41 and the tilt adjustment roller 42. In addition, by providing multiple fixing points, the load on each point is distributed, and damage to each component due to impact is less likely to occur. In this embodiment, sets of the shift adjustment roller 41, the tilt adjustment roller 42, and the fixing member 50 are arranged at three equally spaced locations on the outer circumference of the lens barrel 10.

[0023] The eccentric fixing shaft 70 is a cylindrical member having a fitting portion 71 and a screw insertion portion 72. The elastic member 80 is a donut-shaped member having a through hole e81. The elastic member 80 is made of rubber or urethane material and has elastic force. The eccentric fixing collar 90 is a donut-shaped member having a through hole c91. The diameter of the opening of the through hole c91 differs between the inner circumference side and the outer circumference side of the lens barrel 10, with the outer circumference side being wider than the inner circumference side.

[0024] The fitting portion 71 is fitted into the fixing hole 31 of the lens retaining frame 30, and the eccentric fixing shaft 70 and the lens retaining frame 30 are further fixed by screwing it into the screw hole portion f32 with a screw 73. The eccentric fixing collar 90 has the eccentric fixing shaft 70 inserted through the through hole c91 and is fitted into the fixing member placement hole 21 of the fixing frame 20. The elastic member 80 has the eccentric fixing shaft 70 inserted through the through hole e81 and is positioned so as to be sandwiched between the surface of the lens retaining frame 30 having the fixing hole 31 and the inner circumference side surface of the eccentric fixing collar 90 on the lens barrel 10.

[0025] In this embodiment, the eccentric fixing shaft 70 is fixed to the lens holding frame 30 by a fitting portion 71 and a screw 73, but the method of fixing is not limited to this. For example, the eccentric fixing shaft 70 can be configured to have a threaded portion, and it can be fixed to the lens holding frame 30 by tightening the threaded portion of the eccentric fixing shaft 70 without using a screw.

[0026] The above describes the components constituting the lens barrel 10 according to an embodiment of the present invention. Next, the assembly procedure, alignment method, and fixing method of the alignment mechanism of the lens barrel 10 described in the embodiment will be explained.

[0027] First, the procedure for engaging the fixed frame 20 and the lens holding frame 30 will be explained. First, the shift adjustment roller 41 and the tilt adjustment roller 42 are fitted into the shift adjustment roller placement holes 22 and 23 of the fixed frame 20, and then fixed in place by screwing them into the screw holes s33 and t34 of the lens holding frame 30 with mounting screws 44.

[0028] Next, the fitting portion 71 of the eccentric fixing shaft 70 is fitted into the fixing hole 31 of the lens holding frame 30, and the screw 73 is inserted into the screw insertion portion 72 and tightened into the screw hole portion f32 of the lens holding frame 30 to secure it. Subsequently, the eccentric fixing shaft 70 is inserted into the through hole e81 of the elastic member 80. Finally, the eccentric fixing shaft 70 is inserted into the through hole c91 of the eccentric fixing collar 90, and the eccentric fixing collar 90 is fitted into the fixing member placement hole 21 of the fixing frame 20.

[0029] When fitting the eccentric fixing collar 90 into the fixing member placement hole 21, the insertion amount should be appropriately controlled. If the insertion amount is excessive, the eccentric fixing collar 90 may obstruct the movement of the lens holding frame 30 during the alignment work described later. Conversely, if the insertion amount is insufficient, a gap will be created between the eccentric fixing collar 90 and the elastic member 80, and adhesive may leak from that gap when fixing the lens holding frame 30 and the fixing frame 20, as described later. One way to control the insertion amount is, for example, to create a flange shape A on the inner diameter side of the fixing frame 20 within the inner diameter of the fixing member placement hole 21, as shown in Figure 9, so that the insertion amount is determined by the flange shape when the eccentric fixing collar 90 is fitted into the fixing member placement hole 21. Alternatively, the insertion amount may be controlled by using a jig or tool that controls the amount of push-in when fitting the eccentric fixing collar 90 into the fixing member placement hole 21.

[0030] The fixed frame 20 and the lens holding frame 30 are engaged using the above procedure. Next, the engaged fixed frame 20 and lens holding frame 30 are aligned. In the alignment process, the lens barrel 10 is attached to an alignment jig such as an MTF measuring instrument, and the shift and tilt of the lens holding frame 30 are adjusted while observing the resolution performance. More specifically, the alignment process is performed by inserting a roller rotation tool into the notches 43 of the shift alignment roller 41 and the tilt alignment roller 42, and rotating the shift alignment roller 41 and the tilt alignment roller 42.

[0031] Here, we will explain the change in the relative position between the fixed frame 20 and the lens holding frame 30 during the alignment process. First, in shift adjustment, when the shift alignment roller 41 is rotated, the lens holding frame 30 moves parallel to the plane perpendicular to the optical axis.

[0032] As the lens retaining frame 30 moves parallel to the optical axis in a plane perpendicular to the optical axis, the width of the gap between the lens retaining frame 30 and the eccentric fixing collar 90 fitted to the fixed frame 20 changes. By positioning the elastic member 80 so as to be sandwiched between the lens retaining frame 30 and the eccentric fixing collar 90, the structure is configured to prevent any gap from forming between the lens retaining frame 30 and the eccentric fixing collar 90 fitted to the fixed frame 20.

[0033] Furthermore, the elastic member 80 is made with a thickness greater than or equal to the width of the gap created by the eccentric fixing collar 90 fitted between the lens holding frame 30 and the fixed frame 20 during shift adjustment. This ensures that the elastic member 80 is positioned without gaps even when the gap created by the eccentric fixing collar 90 fitted between the lens holding frame 30 and the fixed frame 20 is at its maximum during shift adjustment. Because the elastic member 80 has elastic force, even when the gap created by the eccentric fixing collar 90 fitted between the lens holding frame 30 and the fixed frame 20 is at its minimum during shift adjustment, the elastic member 80 deforms, so as not to hinder the movement of the lens holding frame 30 during adjustment.

[0034] During tilt adjustment, rotating the tilt adjustment roller 42 causes the lens holding frame 30 to tilt relative to the optical axis. When tilt and shift adjustments are performed, the eccentric fixing shaft 70 fixed to the lens holding frame 30 moves within the inner diameter of the eccentric fixing collar 90. The inner diameter of the eccentric fixing collar 90 is set such that even when the amount of tilting of the lens holding frame 30 relative to the optical axis during tilt adjustment and the amount of parallel movement of the lens holding frame 30 in a plane perpendicular to the optical axis during shift adjustment are simultaneously at their maximum, the eccentric fixing shaft 70 and the inner circumference of the eccentric fixing collar 90 do not come into contact.

[0035] After the alignment work is completed, the fixing member 50 is used to fix the fixing frame 20 and the lens holding frame 30. As shown in Figures 4 and 8, the fixing member 50 has an adhesive portion 60. The adhesive portion 60 is the part to which the adhesive formed by the eccentric fixing shaft 70, the eccentric fixing collar 90, and the elastic member 80 is filled.

[0036] The eccentric fixing shaft 70 is fixed to the lens retaining frame 30, and the eccentric fixing collar 90 is fitted into the fixing frame 20. Therefore, the fixing of the fixing frame 20 and the lens retaining frame 30 is completed by filling the adhesive part 60 with adhesive. This structure allows the fixing frame 20 and the lens retaining frame 30 to be fixed without directly applying adhesive to the fixing frame 20 and the lens retaining frame 30.

[0037] Preferably, the elastic member 80 is configured to contact the inner circumferential surface of the fixing member placement hole 21 and the outer circumferential surface of the eccentric fixing shaft 70. This ensures that the adhesive does not adhere to the fixing frame 20 and the lens holding frame 30, even if the viscosity of the adhesive used makes it easy for the adhesive to flow into the gap between the inner circumferential surface of the elastic member 80 and the outer circumferential surface of the eccentric fixing shaft 70.

[0038] The above describes the assembly procedure, alignment method, and fixing method of the lens barrel 10 alignment mechanism described in this embodiment. Next, the disassembly method for removing the lens holding frame 30 from the fixing frame 20 will be described.

[0039] When removing the lens retaining frame 30 from the fixed frame 20, remove all mounting screws 44 and 73, and remove the shift adjustment roller 41 and tilt adjustment roller 42. At this point, the fixed frame 20 and the lens retaining frame 30 are fixed only by the adhesive joint 60 formed by the eccentric fixing shaft 70, the eccentric fixing collar 90, and the elastic member 80. Grasp the screw insertion part 72 of the eccentric fixing shaft 70 with a tool such as tweezers or pliers, and pull out the fitting part 71 from the fixing hole 31 of the lens retaining frame 30 to remove the eccentric fixing shaft 70 from the lens retaining frame 30. At this time, some or all of the eccentric fixing shaft 70, adhesive, eccentric fixing collar 90, and elastic member 80 will come off the lens retaining frame 30 and the fixed frame 20. If any parts remain, remove the remaining parts with a tool such as tweezers or pliers. The disassembly work is then carried out in this manner.

[0040] Alternatively, instead of disassembling the lens barrel 10, it is possible to readjust the relative position of the fixing frame 20 and the lens holding frame 30 to correct any misalignment. In this case, only the fixing member 50 is removed, replaced with a new fixing member 50, and readjusted. Finally, adhesive is applied to the bonding portion 60 to secure it.

[0041] Furthermore, the present invention can also take the following configuration.

[0042] The eccentric fixing shaft 70 may also have a flange portion 74, as shown in Figure 10. When the eccentric fixing shaft 70 has a flange portion 74, as shown in Figures 11 and 12, the elastic member 80 is positioned so as to be sandwiched between the outer surface of the flange portion 74 on the lens barrel 10 and the inner surface of the eccentric fixing collar 90 on the lens barrel 10. By having a flange portion 74, even if there is a gap between the outer surface of the eccentric fixing shaft 74 and the inner surface of the through hole e81 in the elastic member 80 when adhesive is filled into the adhesive portion 60, the adhesive will not travel along the eccentric fixing shaft 70 and adhere to the lens holding frame 30.

[0043] Furthermore, in this embodiment, only the main parts of the present invention have been described. Other parts can be constructed using well-known techniques related to lens barrels as appropriate.

[0044] As described above, in this invention, adhesive is used to fix the fixing frame 20 and the lens holding frame 30, but the adhesive is not directly applied to the fixing frame 20 and the lens holding frame 30. The adhesive is applied only to the adhesive portion 60, and furthermore, the fixing member 50 having the adhesive portion 60 can be easily removed. Therefore, the lens barrel 10 can be easily disassembled, and components such as the fixing frame 20 and the lens holding frame 30 can be easily reused when performing repairs or readjustments.

[0045] Furthermore, the lens barrel according to the present invention can be appropriately modified depending on the imaging device to which the present invention is applied. In addition, various modifications, changes, and combinations are possible as needed, such as changes in appearance due to changes in the external dimensions of the device, and changes in the joining positions between components, but all of these are within the scope of equivalence of the present invention. [Explanation of Symbols]

[0046] Lens barrel 10 Fixed frame 20 Fixing member placement hole 21 Shift alignment roller placement hole 22 Tilt adjustment center roller placement hole 23 Fixed part 24 Flange shape A Lens holding frame 30 Fixing hole 31 Screw hole portion f 32 Screw hole section s 33 Screw hole portion t 34 Lens group 35 Shift centering roller 41 Tilt-adjusting roller 42 Notch 43 Mounting screws 44 Fixing member 50 Adhesive part 60 Eccentric fixed shaft 70 Fitting part 71 Screw insertion part 72 Bis 73 Flange section 74 Elastic member 80 Through hole e 81 Offset fixing collar 90 Through hole c 91

Claims

1. A lens holding member that holds the lens, A base member fixed to the lens holding member by a fixing member, A lens barrel having an adjustment member for adjusting the relative position between the lens holding member and the base member, The lens holding member has a fixing hole, The base member has placement holes, The fixing member comprises an eccentric fixing shaft fixed in the fixing hole, an elastic member having a through hole through which the eccentric fixing shaft is inserted, and an eccentric fixing collar having a through hole through which the eccentric fixing shaft is inserted and fitted into the positioning hole. The elastic member is sandwiched between the lens holding member and the eccentric fixing collar. A lens barrel characterized in that the lens holding member and the base member are fixed by filling the adhesive portion formed by the eccentric fixing shaft, the elastic member, and the eccentric fixing collar with adhesive.

2. A lens holding member for holding a lens, A base member fixed to the lens holding member by a fixing member, A lens barrel having an adjustment member for adjusting the relative position between the lens holding member and the base member, The lens holding member has a fixing hole, The base member has placement holes, The fixing member comprises an eccentric fixing shaft fixed in the fixing hole, an elastic member having a through hole through which the eccentric fixing shaft is inserted, and an eccentric fixing collar having a through hole through which the eccentric fixing shaft is inserted and fitted into the positioning hole. The aforementioned eccentric fixing shaft includes a flange portion, The elastic member is sandwiched between the flange portion and the eccentric fixing collar. A lens barrel characterized in that the lens holding member and the base member are fixed by filling the adhesive portion formed by the eccentric fixing shaft, the elastic member, and the eccentric fixing collar with adhesive.

3. The lens barrel according to claim 1 or 2, characterized in that the elastic member is in contact with the inner circumferential surface of the arrangement hole and the outer circumferential surface of the eccentric fixing shaft.

4. The lens barrel according to claim 1 or 2, characterized in that the adjusting member is an eccentric roller, and the relative position between the lens holding member and the base member is adjusted by rotating the eccentric roller.

5. The lens barrel according to claim 1 or 2, characterized in that the adjustment is an adjustment that moves the lens holding member in parallel within a plane perpendicular to the optical axis of the lens group.

6. The lens barrel according to claim 1 or 2, characterized in that the elastic member is made of rubber or urethane.

7. A lens holding member having a fixing hole for holding the lens, A base member having a placement hole and fixed to the lens holding member by a fixing member, It has an eccentric roller that adjusts the position of the lens holding member and the base member by rotating it, The fixing member comprises an eccentric fixing shaft fixed in the fixing hole, an elastic member having a through hole through which the eccentric fixing shaft is inserted, and an eccentric fixing collar having a through hole through which the eccentric fixing shaft is inserted. The elastic member is sandwiched between the lens holding member and the eccentric fixing collar in a method for centering a lens barrel. The steps include fixing the eccentric fixing shaft into the fixing hole, The process of inserting the elastic member onto the eccentric fixing shaft, The steps include fitting the eccentric fixing collar into the placement hole, A step of adjusting the lens holding member by rotating the eccentric roller provided on the outer circumference of the lens holding member so that the lens holding member moves parallel to a plane perpendicular to the optical axis of the lens, A step of filling the adhesive portion formed by the eccentric fixing shaft, the eccentric fixing collar, and the elastic member with adhesive so as to fix the lens holding member and the base member in the predetermined position after the adjustment, A method for centering a lens barrel, characterized in that the lens holding member is centered by the above.

Images