JP2004013006A - Lens barrel and method of assembling lens barrel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens barrel in which the combination of a plurality of frame members can be easily managed in the case of assembling the lens barrel. <P>SOLUTION: Although a 1st group frame, a 2nd group frame, a 3rd group frame 1, and a 4th group frame 2 are integrated into the lens barrel, a 3rd group lens 3 and a 4th group lens fitted to the 3rd group frame 1 and the 4th group frame 2 are aligned by a lens centering device. The centered 3rd group frame 1 and 4th group frame 2 are held in an engaged state in which an engaging piece part 1b formed on the 3rd group frame 1 is engaged with a claw 2c formed on the 4th group frame 2 when these frames 1, 2 are carried or stored until they are integrated into the lens barrel. Thereby, no error is generated in the centering/combination of the frames 1, 2 and the frames 1, 2 are engaged with each other in a state that they are approached as closer as possible, occupied space is reduced and the lens barrel can be easily handled. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lens barrel with improved convenience in assembling and a method of assembling the lens barrel.
[0002]
[Prior art]
In a conventional lens adjustment method for a lens barrel having a plurality of lens groups, when spot adjustment (lens core adjustment) between lens groups, for example, between a plurality of lenses, is performed by a core adjustment device, optical adjustment between the lens groups is performed. By reducing the eccentricity (center misalignment between the lens groups), blurring in the periphery can be suppressed, and further, a great effect such as an improvement in the MTF performance at the center of the telephoto is achieved.
[0003]
On the other hand, when the spot adjustment between the groups is not performed, the alignment is performed using an assembling jig. However, in this case, only alignment between the holding frames for holding the lens groups is performed, and optical alignment of the lens groups is not performed, so that sufficient guarantee of optical performance is not always obtained.
[0004]
[Problems to be solved by the invention]
However, when applying the above-described lens adjustment method by spot adjustment between the lens groups using the core adjustment device, a pair of lens groups each provided on another frame member (holding frame, lens group frame) is used. After the adjustment is performed, the lens groups are fixed to the respective holding frames with an adhesive. However, in the subsequent assembly process, it is necessary to manage during the assembly process so that the combination between the pair of lens groups is not changed. Must. Moreover, since the combination between the lens groups is difficult to visually discriminate, the management work is troublesome.
[0005]
The present invention has been made in order to solve the above-described problems, and provides a lens barrel in which the combination management of a plurality of frame members holding a plurality of lens groups is easy, and a method of assembling the lens barrel. The purpose is to provide.
[0006]
[Means for Solving the Problems]
The lens barrel according to claim 1, wherein the first frame member, the second frame member, and the first frame member and the second frame member when the lens barrel is not completed. And engagement means for preventing the first frame member and the second frame member from being separated from each other in the optical axis direction. The two frame members are engaged with each other by the engaging means, and are prevented from being separated from each other.
[0007]
The lens barrel according to a second aspect of the present invention is the lens barrel according to the first aspect, wherein after the product of the lens barrel is completed, the first frame member and the second frame member are relatively movable. It is.
[0008]
In the lens barrel according to a third aspect of the present invention, the first frame member and the second frame member move relative to each other when the engagement means is used as a product of the lens barrel. The first frame member and the second frame member are engaged with each other with a separation amount shorter than the maximum or minimum separation amount.
[0009]
The method for assembling a lens barrel according to claim 4 of the present invention, comprises a first lens, a first frame member for holding the first lens, a second lens, and the second lens. A lens barrel having a second frame member for holding the first lens and engagement means for engaging the first frame member and the second frame member. The second lens is fixed to the second frame member when incorporated in the member, and after the assembly, the first frame member and the second frame member are attached to a core adjusting device, and the second lens is attached to the second frame member. The core adjustment of the first lens for aligning the lens with the core of the first lens is performed by the core adjustment device, and after the alignment is completed, the first frame member and the first frame member are aligned by the engagement means. The second frame member is joined.
[0010]
The method for assembling a lens barrel according to claim 5 of the present invention, comprises a first lens, a first frame member for holding the first lens, a second lens, and the second lens. A lens barrel having a second frame member for holding the first lens member and engagement means for engaging the first frame member and the second frame member, wherein the first lens and the second lens are provided. After the relative center adjustment of the first frame member and the second frame member is performed, the first frame member and the second frame member are engaged by the engagement means.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an exploded perspective view of two lens group frames incorporated in the lens barrel according to the first embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the two lens group frames in an engaged state. FIG. 3 is a longitudinal sectional view showing a state where the two lens group frames are incorporated in a lens barrel and are separated.
[0012]
The lens barrel according to the present embodiment is a four-group lens barrel, and includes a third group frame 1 as a first frame member driven forward and backward during zooming, as shown in FIG. 1, and a second frame member. , A first group frame, a second group frame (not shown), and the like.
[0013]
The third group frame 1 has a guide shaft hole 1a at a lower portion of the frame portion, two cam followers 6 and 7 are fixed at an upper portion of the frame portion, and is an engagement means projecting to a rear outer peripheral portion of the frame portion. And an engagement piece portion 1b having a claw engagement hole 1c. A guide shaft 10 parallel to the optical axis O is fitted into the guide shaft hole 1a, and is adhesively fixed. Further, the engagement piece 1b is formed of a thin plate, and can be elastically deformed by bending vertically.
[0014]
A third group lens 3 as a first lens is fitted into the inner peripheral portion of the third group frame 1 and is adhered and fixed.
[0015]
The fourth group frame 2 has a sleeve hole 2b at a lower portion of the frame portion, cam followers 8, 9 are fixed to upper and lower portions of the frame portion, and a claw 2c as an engagement means is provided at a front portion of the outer periphery of the frame. ing. A sleeve 11 is inserted into the sleeve hole 2b in a loose state, is positioned in a state of being fitted into the guide shaft 10, and is adhesively fixed. The claw 2c can be fitted into the claw engaging hole 1c of the third group frame 1, and has a front inclined surface for pushing up the claw engaging piece 1b of the third group frame 1 when fitted.
[0016]
Further, a fourth-group front lens 4a and a fourth-group rear lens 4b, which are the fourth group lens 4 as the second lens, are fixed to the inner peripheral portion of the fourth group frame 2. However, the fourth group front lens 4a is fitted and adhered and fixed without position adjustment, but the fourth group rear lens 4b is inserted in the lens fitting portion 2a in a loosely fitted state, and the lens center adjustment is performed as described later. It is positioned by the lens core adjustment by the device and is fixed by bonding.
[0017]
Further, the fourth group rear lens 4b is fitted and adhered and fixed without position adjustment similarly to the fourth group front lens 4a, and the relative position between the sleeve 11 and the fourth group frame 2 is positioned by position adjustment by the lens core adjustment device. Alternatively, it may be fixed by bonding. In this case, the claw engagement hole 1c and the claw 2c are provided with play for the adjustment allowance.
[0018]
When adjusting the lens cores of the third group frame 1 and the fourth group frame 2, first, the third group frame 1 to which the third group lens 3 is fixed and the fourth group frame 2 to which the fourth group front lens 4a is fixed. Attach to laser type lens core adjustment device. In the third group frame 1 and the fourth group frame 2, the guide shaft 10 is fitted to the sleeve 11, and the frames are held in a relatively positioned state. Then, the fourth group rear lens 4b is loosely inserted into the lens fitting portion 2a of the fourth group frame 2.
[0019]
Therefore, while observing the spot of the laser beam, the position of the rear lens 4b of the fourth group is shifted and adjusted so as to eliminate the displacement (eccentricity) of the spot between the third group lens 3 and the fourth group lens 4. That is, the relative position between the first lens and the second lens has been adjusted. In the adjusted state, the fourth group rear lens 5 is adhesively fixed to the lens fitting portion 2a. The lens core adjustment may be performed by shifting the third group lens 3 side instead of the fourth group lens 4 side.
[0020]
The third group frame 1 and the fourth group frame 2 whose lens cores have been adjusted are brought into contact with the front and rear portions of both frames as shown in FIG. The claw 2c of the fourth group frame 2 is fitted into 1c to bring it into an engaged state. At this time, the guide shaft 10 is also fitted into the sleeve 11. The third group frame 1 and the fourth group frame 2 in the engaged state are held closer to each other than the separated state in the lens barrel assembled state (product completed state) shown in FIG. Has become.
[0021]
Note that the lens core adjustment may be performed in a holding state that is closer than the separation distance state in the lens barrel assembled state illustrated in FIG.
[0022]
The third group frame 1 and the fourth group frame 2 are held in the engaged state during transportation or storage until they are incorporated into the lens barrel. When assembling into the lens barrel, the engaging piece 1b is lifted upward to remove the claw 2c from the claw engaging hole 1c. The third group frame 1 when incorporated in the lens barrel and at the relative separation position between the third group frame 1 and the fourth group frame 2 while using the lens barrel as a photographing lens, or at the lens retracted position where the separation amount is the minimum. And the fourth group frame 2 are farther apart from each other than in the engaged state.
[0023]
According to the lens barrel of the present embodiment described above, since the lens cores of the third lens group 3 and the fourth lens group 4 are adjusted, blurring in the periphery is suppressed, and the MTF performance at the center of telephoto is also improved. I have. The combined state of the frames whose lens cores have been adjusted is securely maintained by the above-mentioned engaged state during the assembling process, so that there is no mistake in combination.
[0024]
After adjustment of the lens core during the assembly of the lens barrel, until the third lens group frame 1 and the fourth lens group frame 2 are assembled to the lens barrel, the claw 2c is engaged with the claw engaging hole 1c to make the optical axis. The frame is integrally held in a state where the space occupied by the frame in the O direction is made as small as possible. Therefore, the third group frame 1 and the fourth group frame 2 do not interfere during transportation or storage during assembly, and there is no need to pay attention to the combination of the frame members, and management during assembly is easy.
[0025]
Next, a lens barrel according to a second embodiment of the present invention will be described.
FIG. 4 is a perspective view showing an engagement state of two lens group frames incorporated in the lens barrel of the present embodiment. FIG. 5 is a perspective view showing a separated state when the two lens group frames are incorporated in a lens barrel. FIG. 6 is a longitudinal sectional view showing a state where the two lens group frames are attached to the lens core adjusting device in an engaged state. FIG. 7 is a longitudinal sectional view showing a state in which the two lens group frames are incorporated in a lens barrel.
[0026]
The lens barrel of the present embodiment is a lens barrel having a four-group configuration, and includes a third group frame 21 which is a first frame member that can be driven forward and backward as shown in FIG. A fourth group frame 22, which is a frame member, and a first group frame and a second group frame (not shown) are further incorporated therein.
[0027]
The third group frame 21 is formed with a concave tapered surface 21c at the rear end surface of the frame portion, and is an engaging means projecting rearward at the outer peripheral portion of the frame portion, and includes two engaging piece portions 21a having opposed projections 21b. Provided. The engaging piece 21a is elastically deformable in the left-right direction. Although not shown, a cam follower for driving forward and backward is provided on the outer peripheral portion of the frame portion.
[0028]
A third group lens 23 is fitted into the inner peripheral portion of the third group frame 21 and is adhered and fixed.
[0029]
The fourth group frame 2 has a convex tapered surface 22c formed on the front end surface of the frame portion and a convex tapered surface 22d formed on the rear end surface portion of the frame portion. Provided. Although not shown, a cam follower for driving forward and backward is provided on the outer peripheral portion of the frame portion. The convex tapered surface 22c can be joined to the concave tapered surface 21c of the third group frame 21, and the convex tapered surface 22d can be joined to the concave tapered surface 25d of the frame support portion 25 of the lens core adjusting device. . The pin 22a can be clamped inside the projection 21b of the engagement piece 21a of the third group frame 21. The concave tapered surface 21c, the convex tapered surfaces 22c and 22d, and the concave tapered surface 25d are each formed along a conical surface centered on the optical axis O.
[0030]
The fourth group lens 24 is loosely inserted into the frame inner peripheral portion 22b of the fourth group frame 22, is positioned by lens core adjustment by a lens core adjustment device as described later, and is adhesively fixed.
[0031]
When performing the lens core adjustment between the third group frame 21 and the fourth group frame 22, first, the third group frame 21 to which the third group lens 23 is fixed, and the fourth group frame to which the fourth group lens 24 is inserted in a loose fit state. 22 is attached to a laser type lens core adjusting device. In the attached state, as shown in FIG. 6, the third group frame 21 and the fourth group frame 22 join the concave tapered portion 21c and the convex tapered portion 22c to position the mutual frame portions. The concave tapered surface 25d of the frame support portion 25 of the lens core adjusting device is joined to the convex tapered portion 22d of the lens frame 22, and the frame portion of the fourth lens frame 22 is positioned with respect to the lens core adjusting device. In the joined state, the pin 22a of the fourth group frame 22 is clamped inside the projection 21b of the engaging piece 21a of the third group frame 21.
[0032]
Therefore, while observing the spot of the laser beam, the position of the fourth lens group 24 is shifted and adjusted so as to eliminate the displacement (eccentricity) of the spot between the third lens group 23 and the fourth lens group 24. In the adjusted state, the fourth lens group 24 is bonded and fixed to the lens fitting portion 22b. The lens core adjustment may be performed by shifting the third group lens 23 side instead of the fourth group lens 24 side.
[0033]
When the third group frame 21 and the fourth group frame 22 whose lens cores are adjusted are transported or stored until they are incorporated into the lens barrel, as shown in FIG. It is held in a state in which it is engaged with the inside with 21b. The third group frame 21 and the fourth group frame 22 in the engaged state are held closer to each other than the separation distance in the lens barrel assembled state (product completed state) shown in FIGS. 5 and 7, and must be removed. If it does not come off easily.
[0034]
The third group frame 21 and the fourth group frame 22 disengage the pin 22a from the projection 21b of the engagement piece 21a when incorporated in the lens barrel. Then, it is fitted into the inner periphery of the holding frame 20 of the lens barrel.
[0035]
According to the lens barrel of the present embodiment described above, similarly to the case of the lens barrel of the first embodiment, since the third lens group 23 and the fourth lens group 24 are adjusted for their lens cores, Blur is suppressed, and the MTF performance centered on tele is also improved. In addition, the combination state of the frames whose lens cores have been adjusted is maintained by the above-mentioned engagement state, so that a combination error does not occur.
[0036]
After the adjustment of the lens core during the assembly of the lens barrel, the third group frame 21 and the fourth group frame 22 are engaged with the pin 22a and the projection 21b of the engagement piece 21a for a period until assembly to the lens barrel. Thus, the frame is integrally held in a state where the space occupied by the frame in the optical axis O direction is reduced as much as possible. Therefore, the third group frame 1 and the fourth group frame 2 do not interfere with the transportation and storage during assembly, and it is not necessary to pay attention to the combination of the frame members, and the management during assembly is easy.
[0037]
【The invention's effect】
As described above, according to the present invention, it is not necessary to pay attention to the combination of the frame members after adjusting the two frame members incorporated in the lens barrel, and the management at the time of assembly becomes easy.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of two lens group frames incorporated in a lens barrel according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view of the two lens group frames of FIG. 1 in an engaged state.
FIG. 3 is a longitudinal sectional view showing a state where the two lens group frames of FIG. 1 are incorporated in a lens barrel and are separated.
FIG. 4 is a perspective view showing an engaged state of two lens group frames incorporated in a lens barrel according to a second embodiment of the present invention.
FIG. 5 is a perspective view showing a separated state when the two lens group frames of FIG. 4 are incorporated in a lens barrel.
6 is a longitudinal sectional view showing a state where the two lens group frames of FIG. 4 are attached to a lens core adjusting device in an engaged state.
FIG. 7 is a longitudinal sectional view showing a state where the two lens group frames of FIG. 4 are assembled in a lens barrel.
[Explanation of symbols]
1,21
... 3rd group frame (first frame member)
2,22
... Fourth group frame (second frame member)
1b ... engaging piece (engaging means)
2c ... claw (engaging means)
21a ... engaging piece (engaging means)
22a ... engaging pin (engaging means)

Claims (5)

A first frame member;
A second frame member;
When the lens barrel is not completed, the first frame member and the second frame member are engaged, and the first frame member and the second frame member are separated from each other in the optical axis direction. Engagement means for preventing
A lens barrel comprising: 2. The lens barrel according to claim 1, wherein after completion of the lens barrel product, the first frame member and the second frame member are relatively movable. When the lens barrel is used as a product, the engagement means is configured to move the first frame member and the second frame member relative to each other and to move the first frame member and the second frame member to a maximum or minimum distance. 2. The lens barrel according to claim 1, wherein the first frame member and the second frame member are engaged with each other. A first lens, a first frame member for holding the first lens, a second lens, a second frame member for holding the second lens, and the first frame member A lens barrel having engagement means for engaging the second frame member with the second frame member. When the first lens is incorporated in the first frame member, the second lens is connected to the second frame member. The first frame member and the second frame member are fixed to a member, and after being assembled, the first frame member and the second frame member are attached to a core adjusting device, and the second lens for aligning the core of the second lens with the core of the first lens. A lens barrel for adjusting the center of the first lens by the center adjusting device, and after completion of the center adjustment, the first frame member and the second frame member are coupled by the engagement means; How to assemble. A first lens, a first frame member for holding the first lens, a second lens, a second frame member for holding the second lens, and the first frame member In a lens barrel having an engagement means for engaging the first frame and the second frame member, after the relative center adjustment between the first lens and the second lens is performed, A method for assembling a lens barrel, comprising: engaging a first frame member with the second frame member.

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