JP5004536B2 - Zoom lens barrel and camera or digital camera equipped with them - Google Patents

Description

  The present invention relates to a zoom lens barrel having an insertion / removal mechanism that retracts at least one lens group in a direction perpendicular to the optical axis in a non-photographing state and inserts the lens group onto the optical axis at the time of photographing. A biasing member is attached to the lens group to be removed in an oblique direction with respect to the optical axis, and in the insertion / removal and zooming operations of the lens group, positioning is performed in a direction perpendicular to the optical axis and parallel to the optical axis. The present invention relates to a zoom lens barrel that is excellent in assemblability and cost by being performed with a member.

  Conventionally, a mechanism relating to a bifocal lens barrel mainly by insertion / removal of a converter lens has been proposed as a mechanism for inserting / removing a photographing lens in a direction perpendicular to the optical axis. Recently, however, cameras using zoom lens barrels have become popular, and converter lenses with a one-point focal length (super wide focal length) that exceeds the zoom range of the zoom lens barrel than the bifocal barrel. There has been proposed a lens barrel for performing insertion and removal.

  Patent Document 1 discloses a lens barrel having a mechanism for unlocking a converter lens that has been fixed by moving a variable magnification lens and inserting and removing it on the optical axis so that the focal length is further shortened than the wide angle of the photographing lens. Has been proposed.

  Patent Document 2 proposes a video camera that senses insertion / removal of a converter lens with a sensor and performs recording only in an inserted state or a retracted state.

  Patent Document 3 proposes a lens barrel in which a converter lens retracted from the optical axis is moved to a space opened by a D-cut of a photographing lens to increase space efficiency in a retracted state.

  In addition, in order to shorten the total length in the optical axis direction during storage, a lens barrel that retracts a part of the photographing zoom lens in a direction perpendicular to the optical axis has been proposed.

  In Patent Document 4, a part of a photographing zoom lens composed of two front and rear groups is retracted in a direction orthogonal to the optical axis, and after detecting that the sensor has been retracted, the front group lens is connected to the rear group lens and the optical axis. A camera has been proposed in which the entire length of the lens barrel during storage is shortened by retracting the lens to substantially the same position in the direction.

  Patent Document 5 proposes a lens barrel in which a part of a photographic zoom lens group is retracted in a direction perpendicular to the optical axis and further moved in the optical axis direction to further shorten the total length of the lens barrel when stored. Has been.

  Further, as conventional techniques relating to an optical system decentering adjustment method, a “lens optical axis adjusting device” disclosed in Patent Document 6, an “optical unit eccentricity adjusting mechanism” disclosed in Patent Document 7, and disclosed in Patent Document 8. There is a “method for bonding and fixing optical components”.

  In the invention disclosed in Patent Document 6, since the error of the optical axis of the lens element and the lens group is within a range of several μm when the contrast value is maximized, the adjustment fixing frame and the adjustment frame are bonded to the adhesive in this state. The fixing frame for adjustment and the adjustment fixing frame integrated with each other and taken out from the mounting hole of the expansion portion of the adjustment frame.

  In the invention disclosed in Patent Document 7, in the lens group that adjusts the optical axis of the first and second optical systems, by fixing both lens units using a holding member, the bonding work in the alignment process is separated. It is possible to carry out in the process and reduce the man-hours of the alignment process.

In the invention disclosed in Patent Document 8, an adhesive (UV curable adhesive) is applied to a lens system, and the lens is fixed by irradiating ultraviolet rays.
No. 7-36356 Japanese Patent No. 2672149 JP-A-7-199019 JP 2003-149723 A JP 2003-315861 A Japanese Patent Laid-Open No. 2003-066298 JP 2003-161868 A JP 2001-27723 A

  In recent small cameras (including digital cameras), there is a growing need for higher zoom magnification and smaller size. However, in order to increase the zoom ratio, it is necessary to increase the number of lenses, which makes it difficult to reduce the size.

In the photographing state, in order to obtain a necessary photographing magnification, it is indispensable to increase the total length in the optical axis direction. Therefore, the total length of the lens barrel storage state in the non-photographing state becomes a problem.
However, since the number of lenses is increased by increasing the magnification, there is a limit to shortening the total length even when the lens barrel is housed.

  Therefore, in recent years, in order to overcome this situation, a zoom lens that shortens the overall length by eliminating the thickness of the lens group by retracting at least a part of the lens group of the zoom lens barrel from the optical axis in the retracted state. The lens barrel has been commercialized.

  In the invention disclosed in Patent Document 1, the converter lens, which has been fixed by moving the variable magnification lens, is unlocked and inserted on and removed from the optical axis so that the focal length is further shortened than the wide angle of the photographing lens. However, the addition of a converter lens only adds a one-point focal length in addition to the zoom area, and does not contribute to shortening the total length of the storage state.

  The invention disclosed in Patent Document 2 senses insertion / removal of the converter lens with a sensor and performs recording only in the inserted state or the retracted state, but this also does not contribute to shortening the total length in the retracted state. .

  In the invention disclosed in Patent Document 3, the converter lens retracted from the optical axis is moved to the space opened by the D-cut of the photographing lens to increase the space efficiency in the retracted state, but the converter lens is orthogonal to the optical axis. The optical axis of the converter lens is tilted by 90 degrees and the mechanism is complicated mechanically, making it difficult to increase accuracy.

  In the invention disclosed in Patent Document 4, the rear group of the photographing zoom lens composed of the front and rear two groups is retracted in a direction orthogonal to the optical axis, and the front group lens is moved to the rear group after the sensor senses the retract. By retracting the lens to almost the same position in the optical axis direction, the total length of the lens barrel when retracted is shortened, but with such a mechanism, the retracted lens group only retracts in the direction perpendicular to the optical axis. Less effective for shortening the overall length. In addition, this mechanism cannot be used with a high-magnification zoom lens barrel in which all the front and rear groups protrude forward from the camera body.

  In the invention disclosed in Patent Document 5, a part of the lens group of the photographing zoom lens is retracted in a direction orthogonal to the optical axis and further moved in the optical axis direction, thereby further reducing the total length of the lens barrel when stored. However, with such a mechanism, only one torsion spring is applied as the urging member of the lens group to be inserted and removed, and the force is applied only in the direction perpendicular to the optical axis, improving the positional accuracy. I can't.

  In addition, in an assembling process of a lens barrel that requires assembling accuracy, it is also required to efficiently perform an optical axis adjustment so-called alignment and an adhering process after alignment in order to realize it.

In the invention disclosed in Patent Document 6, the unit that has been aligned and fixed on the aligning device is taken out last. That is, the fixing work after alignment is performed on the alignment device.
Therefore, the time for occupying the aligning device includes the time for performing the fixing work, and the work efficiency of the aligning work deteriorates.

  In the invention disclosed in Patent Document 7, the urging holding member is configured integrally with the lens frame. This member aligns the first and second optical systems, and can be left as it is or can be removed after bonding. However, even in this configuration, it is necessary to prepare a space for attaching the urging member to the lens frame, which is not sufficient to reduce the size of the lens frame to be aligned.

In the invention disclosed in Patent Document 8, alignment work and adhesive curing work are performed on an alignment device. That is, the fixing operation after alignment is performed on the alignment device.
Therefore, the time for occupying the aligning device includes the time for performing the fixing work, and the work efficiency of the aligning work deteriorates.

  The present invention has been made in view of such problems, and is a zoom lens barrel that achieves high zoom magnification and miniaturization by inserting / removing at least one lens group in a direction orthogonal to the optical axis. An object of the present invention is to provide a zoom lens barrel in which the positional accuracy in the optical axis direction of the lens group to be inserted and removed and the positional accuracy in the optical axis direction of other adjacent lens groups are stabilized without increasing the number of parts. And

In order to achieve the above object, the present invention provides, as a first aspect, a first lens group disposed on the subject side and a second lens group disposed on the image plane side with respect to the first lens group. And a third lens group disposed further on the imaging plane side than the second lens group, and retracts the second lens group in a direction perpendicular to the optical axis in a non-photographing state. A zoom lens barrel having an insertion / removal mechanism, comprising a zoom finder device interlocked with the first lens group, wherein the second lens group is located between objective lens groups of the zoom finder device in a non-shooting state. The urging member attached to the second lens group urges the second lens group not only in the direction perpendicular to the optical axis in the non-photographing state but also in the optical axis direction. A zoom lens barrel characterized by It is intended to.

In the first aspect of the present invention, it is preferable that the other end of the urging member is attached to the third lens group.

  In any of the above configurations of the first aspect of the present invention, the third lens group is preferably a focus lens. In addition, the first lens group, the second lens group, and the third lens group More preferably, the lens group is driven by a different motor to perform zooming and focusing.

In any of the above configurations of the first aspect of the present invention, it is preferable that the urging member urges the third lens group in a direction substantially parallel to the optical axis in the photographing state. Further, interpolation disengaging mechanism includes a second lens unit inserted on the optical axis during the transition from the non-shooting state to the photographing state, the optical axis of the second lens group during the transition from the photographing state to the non-photographing state It is preferable to evacuate.

  In order to achieve the above object, the present invention provides, as a second aspect, a camera including a zoom lens barrel according to any one of the above-described configurations of the first aspect of the present invention.

  In order to achieve the above object, the present invention provides, as a third aspect, a digital camera including the zoom lens barrel according to any one of the above-described configurations of the first aspect of the present invention. .

  According to the present invention, there is provided a zoom lens barrel in which at least one lens group is inserted / removed in a direction orthogonal to the optical axis, thereby achieving high zoom magnification and miniaturization. It is possible to provide a zoom lens barrel in which the positional accuracy in the optical axis direction and the positional accuracy in the optical axis direction of other adjacent lens groups are stabilized without increasing the number of components.

[First Embodiment]
A first embodiment in which the present invention is suitably implemented will be described. FIG. 1 is an exploded perspective view of the zoom lens barrel according to the present embodiment.
The zoom lens according to the present embodiment includes a first lens group 1, a second lens group 2, a third lens group 3, a fourth lens group 4, a first lens frame 5, a second lens frame 6, and a shutter. 7, a fixed cylinder 8, a first rectilinear key 9, a second rectilinear key 10, an inner cam 11, a second rotating cylinder 12, a first rotating cylinder 13, and a base 21.
Of the above lens groups, the third lens group 3 is a lens group that is inserted and removed in a direction perpendicular to the optical axis, and the fourth lens group is a focus lens.
The first lens frame 5 holds the first lens group 1. The second lens frame 6 holds the second lens group.

  In this zoom lens barrel, the first lens group 1, the second lens group 2, and the shutter 7 are driven to rotate by a first zoom motor (not shown) to move in the optical axis direction, and the second zoom motor 14. As a result, the third lens group 3 is moved in the optical axis direction to change the magnification. Further, focusing is performed by moving the focus lens 4 in the optical axis direction by the focus motor 15.

FIGS. 2 and 3 show the housed state and the used state of the zoom lens barrel according to the present embodiment, respectively.
In the retracted state, the second zoom motor 14 is driven to move the nut 19 to the image plane side, and the cam 16b on the third lens frame 16 that holds the third lens group 3 is pushed, so that the third The lens frame 16 is rotated about the rotation axis 17 and deviates from the optical axis O. Note that the end 19a of the nut 19 is restricted in rotation by a part of the base 21 (not shown), and moves straight on the axis of the second zoom motor 14.
Then, the spring 18 installed between the third lens frame 16 and the fourth lens frame 17 is charged by the retracting operation of the third lens frame 16. The focus lens 4 is held by the fourth lens frame 17 and is moved in the optical axis direction by the main shaft 22, the sub shaft 23, and the focus motor 15.

When the user turns on the power switch, the zoom lens barrel shifts to the use state shown in FIG. The operation at that time is as follows.
When the power switch is turned on, the second zoom motor 14 is first driven. Then, the nut 19 moves straight toward the subject side and is separated from the cam 16 b of the third lens frame 16, and the third lens frame 16 can be rotated around the rotation shaft 17. This lens group 3 is moved in the optical axis direction, and the third lens frame stopper prevents rotation at the position where the distance between the third lens group 3 and the fourth lens group 4 is the shortest.

Note that the spring 18 is set so that the power always remains even when the distance between the third lens group 3 and the fourth lens group 4 is the shortest. Thus, the center of the third lens group is always fixed at a position that coincides with the optical axis. Further, when the second zoom motor 14 is driven, the nut 19 further moves toward the subject, contacts the contact portion 16a of the third lens frame 16, and moves the third lens frame 16 in the optical axis direction. . The focusing operation can be performed by moving the fourth lens frame 17 in the optical axis direction by driving the focus motor 15.
In addition, since the spring 18 is installed between the third lens frame 16 and the fourth lens frame 17, the third lens frame 16 and the fourth lens frame 17 are urged in directions opposite to each other, Operation is always stable.

Although the third lens group 3 is retracted to the lower right in a front view, it can be retracted to the inner surface of the zoom finder device at the upper part of the lens barrel by changing the layout. In this case, since the third lens frame 16 is retracted between the housed state and the used state, the zoom lens of the zoom finder device does not need to stay in a predetermined position, and the subject for the third lens frame 16 retracts. The space where the third lens frame 16 is retracted can be easily secured.
A zoom finder device interlocked with the first lens group 1 and the second lens group 2 is provided on the upper or upper right / left upper part of the zoom lens barrel. By setting the interval, the retracted third lens group 3 can be prevented from interfering with other camera body parts.

  Here, although the configuration in which the other end of the spring 18 attached to the third lens group 3 is attached to the fourth lens frame 17 is described as an example, the other end of the spring 18 may be attached to the base 21. In this way, the difference in use length of the spring 18 between the storage time and the photographing time becomes small, and the life of the spring 18 can be extended.

  Thus, in the zoom lens barrel according to the present embodiment, the spring 18 attached to the third lens group 3 is attached in an oblique direction with respect to the optical axis in the non-photographing state, so that the optical axis As a result, the position of the third lens group 3 can be increased.

  Further, by attaching the other end of the spring 18 to the fourth lens frame 17, an urging member in the optical axis direction of the third lens group 3 becomes unnecessary, so that the assembling property is improved and the manufacturing cost can be reduced. In addition, since the fourth lens group 4 is a focus lens, the difference in urging force between the proximity end and the infinite end is reduced.

  Further, since the spring 18 is substantially parallel to the optical axis in the photographing state, the movement of the third lens group 3 and the fourth lens group 4 on the optical axis can be stabilized.

  The first lens group 1, the second lens group 2, the third lens group 3, and the fourth lens group 4 are different motors (first zoom motor, second zoom motor 14, focus motor 15). ) To perform zooming and focusing, the moving distance on the optical axis is not limited, and high magnification can be easily achieved.

  Further, by controlling the insertion / removal mechanism so that the third lens group 3 is inserted on the optical axis during the transition from the non-photographing state to the photographing state and retracted during the transition from the photographing state to the non-photographing state, The zoom lens barrel can be increased in magnification and size.

  A camera (including a digital camera) using the zoom lens barrel according to the present embodiment has a short overall length in the optical axis direction of the zoom lens barrel, is excellent in assemblability, and is low in manufacturing cost.

[Second Embodiment]
A second embodiment in which the present invention is suitably implemented will be described.
FIG. 4 shows the configuration of the lens barrel according to the present embodiment. The optical system unit 100 includes three lens groups, a first group 101, a second group 102, and a third group 103.
Here, the case where the inside of the second group 102 is aligned will be described.
The optical system unit 100 is disposed on an optical system unit receiver 201 in the aligning device shown in FIG.
In the aligning device, a light source 202 and a projection chart 203 are arranged, and a projected image is projected onto the projection plane 400 through the entire optical system in the aligning master.

  The alignment is performed while observing the quality of the projection image projected on the projection plane 400.

  As shown in FIG. 6, the second group 102 that is the subject of alignment constitutes a first sub-lens group 1021 that includes an aligned lens 1021 a and an aligned lens frame 1021 b, and a second group 102. Among these, the second sub lens group 1022 excluding the first sub lens group 1021 is configured.

  Alignment is performed by moving the first sub lens group 1021 with respect to the second sub lens group 1022 in a direction substantially orthogonal to the optical axis.

  The alignment of the second group 102 is performed in a state of being accommodated in the lens frame cartridge 104.

7 and 8 show the configuration of the lens frame cartridge 104. FIG.
In the initial state, the lens frame cartridge 104 exists alone and is separated from the optical system unit 100.
First, the second group 102 is set in the lens frame cartridge 104. The setting method is to set the lens group cartridge 104 so that the surface perpendicular to the outer diameter and the optical axis of the second group 102 is applied with reference to the inner diameter of the lens frame cartridge 104 and the surface perpendicular to the optical axis. Hold by the clamp 1041.

  Further, as shown in FIG. 6, in order to hold the first sub lens group 1021 before adjustment, the first sub lens group 1021 is urged by the to-be-aligned lens urging member 300. By holding the bias, the first sub lens group 1021 is held, and the first sub lens group 1021 is prevented from being displaced after alignment.

  An aperture 1025 is provided in the aligned lens urging member 300. In the case of an optical system in which a stop is positioned in front of a lens group to be aligned, the appropriate image performance can be evaluated when the entire system is projected during alignment by providing the stop.

  In the case of an optical system in which an aperture is located in front of the lens group that is the subject of alignment, the aperture is provided on the to-be-aligned lens biasing member. Since an appropriate image evaluation can be performed, alignment with high accuracy is possible.

  By providing the stop 1025 integrally with the to-be-aligned lens urging member 300, it is not necessary to separately provide a stop member when aligning a lens group that requires a stop. Therefore, the configuration of the lens frame cartridge 104 and the configuration of the optical system unit 100 can be simplified. Further, with a simple configuration, it is possible to improve the handling of the lens frame cartridge 104, and the efficiency of the alignment work is improved.

  By holding and fixing the first sub lens group 1021 that is aligned, the second sub lens group 1022 that does not move during alignment can be stabilized. Further, by providing a member for urging the first sub lens group 1021 in the optical axis direction, the position of the first sub lens group 1021 can be stabilized before and after alignment, and after alignment, The sub lens group 1021 can be stably held until it is fixed. Accordingly, it is possible to separate the setup process and the alignment process from the alignment stage and the fixing process.

  As a method of urging the first sub-lens group 1021, a method of urging the lens through the centered lens frame 301 as shown in FIG. 6, or a first sub-lens group as shown in FIG. There is a method of directly energizing the 1021 aligned lens 1021a.

  Next, the lens frame cartridge 104 in which the second group 102 is set is set in the optical system unit 100 for alignment.

  The optical system unit 100 includes a first group 101 and a third group 103, and a space for inserting the lens frame cartridge 104 is provided. The lens frame cartridge 104 in which the second group 102 is set is inserted into this space.

  By inserting the lens frame cartridge 104, the optical system unit 100 has a configuration in which the entire optical system is configured. In this state, the image of the projection chart 203 is projected through the optical system unit 100 in which the entire optical system is configured.

  While looking at the quality of the projected image, the XY stage 204 and the focus adjustment micro 205 are operated to perform alignment.

  As shown in FIGS. 9 and 10, the XY stage 204 is provided with a chucking portion 208 and an arm portion 209 integrally with a slide stage 207 capable of moving forward and backward in the direction of the second group frame cartridge 206. Yes.

  When the second group frame cartridge 206 is attached to and detached from the optical system unit 100, the chucking portion 208 needs to be retracted from the second group frame 209 as shown in FIG. During alignment, the slide stage 207 is moved to the second group frame cartridge 206 and the first sub lens group 1021 is chucked by the chucking portion 208.

  By operating the XY stage 204 in this state, the first sub-lens group 1021 can be moved in a direction substantially perpendicular to the optical axis with respect to the second sub-lens group 1022 to perform alignment.

At this time, the first lens frame (aligned lens frame 1021b) is in a state of being urged by the tuned lens urging member 300. Since the to-be-aligned lens urging member 300 moves together with the first sub-lens group 1021 that moves in a direction substantially perpendicular to the light source 202 during alignment, as shown in FIGS. A backlash is given to the hole of the tuned lens urging member 300.
This backlash takes a gap of about 0.1 to 0.2 mm in diameter, allowing for an amount of + α to be moved in a direction substantially perpendicular to the optical axis during alignment. With such a configuration, the to-be-aligned lens urging member 300 can be moved together with the first sub lens group 1021.

  Since the to-be-aligned lens urging member 300 can move together with the first sub-lens group 1021 in a direction substantially perpendicular to the optical axis (alignment direction), the first sub-lens group 1021 can be stably provided. Can be held.

  After alignment, the slide stage 207 is retracted from the second group frame cartridge 206 and the second group frame cartridge 206 is removed from the optical system unit 100.

Since the aligned first sub-lens group 1021 is held by the to-be-aligned lens urging member 300, the adjustment position is maintained as it is after being taken out from the optical system unit 100.
In this state, it is fixed by an adhesive means or the like in the next step.

  In a state where the lens frame cartridge 104 is removed from the master lens frame, an adhesive application unit 1024 provided between the second lens group 1023 that holds the aligned lens urging member 300 and the second sub lens group 1022. It is possible to apply an adhesive to the film and fix it by UV irradiation or the like. In this state, since there is no chucking member as shown in FIGS. 13 and 14, a sufficient adhesion region can be secured.

Since the bonding operation can be performed with the first sub lens group 1021 biased, the bonding operation can be performed with the position of the first sub lens group 1021 after alignment being stabilized. Therefore, after the alignment, after the second group frame cartridge 206 is taken out from the alignment master, it can be adhered with high accuracy as it is, and the workability is good.
Further, it is possible to prevent the occurrence of misalignment due to curing shrinkage when the adhesive is cured, and high-precision alignment is possible.

  After the first sub lens group 1021 is fixed, the centered lens urging member 300 is retracted, the second group frame clamp 210 is released, and the second group 102 is taken out.

  The lens frame cartridge 104 held together with the lens frame 1023 of the second group 102 housed in the optical system unit 100 at the time of alignment can be attached to and detached from the optical system unit 100 by the process as described above.

  As shown in FIG. 15, the second group 102 that has been aligned by the optical system unit 100 is configured with the first group 101 as a rectilinear cylinder 104 and a rotating cylinder 105, and constitutes a lens barrel with the third group 103. . The illustrated configuration is a lens barrel of a digital camera provided with an image sensor 106, but the same applies to a lens barrel of a silver salt camera.

Since the to-be-aligned lens urging member 300 urged by the first sub lens group 1021 that is the subject of alignment need not be provided as the configuration of the lens group that is the subject of alignment (second group 102). Therefore, it is possible to reduce the size of the lens group to be aligned.
Therefore, it becomes possible to efficiently arrange functional parts indispensable for the configuration of the lens barrel, and the lens barrel can be reduced in size.

  A camera can be constructed by incorporating this lens barrel into the camera body. Thereby, a camera can be reduced in size.

As shown in FIG. 9, the lens frame cartridge 104 chucks the first sub-lens group 1021 at the time of alignment work, and in a direction substantially orthogonal to the optical axis by the XY stage 204 integrally provided. By moving, it can be moved in the alignment direction.
As shown in FIGS. 13 and 14, the chucking portion 208 chucks the cylindrical outer periphery of the centering lens urging member 300 in addition to chucking the first sub lens group 1021. Is also possible.

A means for moving the lens frame cartridge 104 in a direction substantially perpendicular to the optical axis (alignment direction) by moving the lens frame cartridge 104 in a direction substantially orthogonal to the optical axis by an external force is configured separately from the lens frame cartridge 104. In other words, the configuration of the lens frame cartridge 104 is limited to the configuration necessary to hold the lens that is the subject of alignment, and the configuration of the lens frame cartridge 104 is simplified by providing an external mechanism for moving in the alignment direction. Can be
With such a configuration, the lens frame cartridge 104 can be easily handled, workability can be improved, and the manufacturing cost of the lens frame cartridge 104 can be reduced.

  The lens group configured by the lens frame cartridge and made removable from the optical system unit 100 after alignment may be any group other than the lens group closest to the subject. In the above example, the second group 102 constituted by the lens frame cartridge 104 is detachable from the optical system unit 100 after alignment, but this may be the third group 103. It goes without saying that the fourth group and the fifth group may be used as long as the optical system has more groups.

Thus, the lens barrel according to the present embodiment is in the alignment of the lens group,
(1) Setup of alignment work before alignment (2) alignment operation on alignment device (3) Fixing operation after alignment can be separated.
For this reason, the time which occupies the alignment apparatus in the alignment process can be shortened. Therefore, it is possible to increase the number of lens groups that can be adjusted per unit time within a unit time.
During mass production, the required number of aligning devices can be reduced, and capital investment in the mass production process can be reduced. By suppressing the capital investment of an expensive aligning device, it is possible to reduce the cost of the lens group to be aligned.

  Further, since the lens frame cartridge can be taken out of the optical system unit and handled after alignment, it is easy to apply the adhesive to the lens group located in the middle. Since it is easy to determine the conditions for curing the adhesive, it can be fixed in a short time. Therefore, the working efficiency can be increased, and the cost for aligning the lens group can be reduced.

  Further, if the lens group to be aligned is provided with a configuration for separating the operations (1), (2), and (3), the holding member for holding the first sub lens group is aligned. Since the lens group must be provided, the configuration of the lens group becomes complicated and the size is increased. Further, the urging member itself configured in the lens group is wasteful because it becomes a non-functional useless part after the first sub-lens group is bonded after alignment.

As in this embodiment, if the lens group cartridge has a lens group biasing member that aligns,
(A) The configuration of the lens group to be aligned can be simplified, and the number of parts required for biasing can be reduced. For this reason, it is possible to reduce the size of the lens group to be aligned.
(B) If the urging member for urging the first sub lens group to be aligned is configured in the form of a lens frame cartridge, the lens frame cartridge will be after alignment / fixation of the lens group to be aligned. In order to replace the lens group with the next alignment, the member for urging the first sub lens group can be used repeatedly.

[Third Embodiment]
A third embodiment in which the present invention is preferably implemented will be described.
FIG. 16 shows a configuration of a lens barrel of the zoom lens according to the present embodiment. The lens of the photographing optical system is designed with an image circle that covers the entire surface of the image pickup element range of the CCD 121. Incident light to the lens barrel is restricted by a lens barrel exterior component 111 that is attached to the front end of the lens barrel and has an opening through which the outermost ray 125 passes, and prevents harmful light from entering the lens barrel.

FIG. 17 shows a configuration of a lens barrel using a CCD 127 having a smaller imaging element range 128 than the CCD 121 of the zoom lens barrel.
A light beam limiting means 126 made of a sheet-like material having an opening is provided on the CCD 127 side of the lens 110 to limit entry of harmful light into the periphery of the imaging element range 128. Since the lens barrel shown in FIG. 17 has a lens barrel exterior component 111 that is common to the lens barrel shown in FIG. 16, more than necessary rays enter the CCD 127 into the lens barrel. 126 restricts unnecessary light intrusion and reduces image deterioration.
The outermost light ray 125 incident from the opening of the exterior component 1111 is indicated by a solid line, and the outermost light ray 124 incident on the imaging element range 128 is indicated by a dotted line. The outermost light ray 125 is actually restricted by the light ray limiting means 126 and cannot reach the CCD 127 side.

FIG. 18 shows a configuration of a lens barrel using a CCD 127 having an imaging element range 128 smaller than that of the CCD 121 of the zoom lens barrel shown in FIG.
The exterior component 129 attached to the tip of the lens barrel is a parallel plate that is made of glass or resin and transmits light. A paint having an opening centered on the optical axis as a light beam limiting member is printed on the exterior component 129 to limit light reaching an area other than the imaging element range 128. The outermost light ray 124 incident on the image sensor range 127 is indicated by a dotted line. A light ray 125 indicated by a solid line is restricted by the light ray limiting means 130 and cannot actually reach the inside of the lens barrel. Image deterioration is prevented by limiting the incidence of unnecessary light into the lens barrel.

FIG. 19 shows a configuration of a lens barrel using a CCD 127 having an imaging element range 128 smaller than that of the CCD 121 of the zoom lens barrel shown in FIG.
The exterior component 133 has an opening centered on the optical axis, and restricts light reaching the image sensor range 1128 of the CCD 127 (out of the light rays 125 entering the lens barrel, enter the image sensor range 127. The outermost ray 124 is indicated by a dotted line). The opening shielding means 131 intended to protect the lens shields the opening of the exterior component 133 by the opening shielding means driving mechanism 132 during non-photographing, thereby protecting the lens. The retracting space in the direction perpendicular to the optical axis of the opening shielding means 131 is determined by the space generated by the difference between the opening size of the exterior part 1 of the lens barrel shown in FIG. 16 and the opening size of the exterior part 133 shown in FIG. The opening shielding means 131 can be completely retracted from the opening of the exterior component 133.

  In this way, the lens barrel can accommodate image sensors with different shapes and sizes, and in the case of image sensors with different shapes and sizes, by selecting or adding a light beam limiting member according to the shape and size of the image sensor. Unnecessary light can be prevented from entering the vicinity of the image sensor, and flare and ghost can be prevented.

  Each of the above embodiments is an example of a preferred embodiment of the present invention, and the present invention is not limited to these and can be variously modified.

It is a figure which shows the structure of the zoom lens-barrel concerning 1st Embodiment which implemented this invention suitably. It is a figure which shows the accommodation state of the zoom lens barrel concerning 1st Embodiment. It is a figure which shows the use condition of the zoom lens-barrel concerning 1st Embodiment. It is a figure which shows the structure of the lens barrel concerning 2nd Embodiment which implemented this invention suitably. It is a figure which shows the structure of the 2nd group which urged | biased the 1st sub lens group directly. It is a figure which shows the structure of the 2nd group which urged | biased the lens via the to-be-aligned lens frame. It is a figure which shows the structure of a lens frame cartridge. It is a figure which shows the structure of a lens frame cartridge. It is a figure which shows the structure of an XY stage. It is a figure which shows the structure of an XY stage. It is a figure which shows the state which gave backlash to the urging | biasing spring axis | shaft and the hole of the to-be-aligned lens urging member. It is a figure which shows the state which gave backlash to the urging | biasing spring axis | shaft and the hole of the to-be-aligned lens urging member. It is a figure which shows the state which chucked the 1st sub lens group. It is a figure which shows the state which chucked the cylindrical outer periphery of the to-be-aligned lens biasing member. It is a figure which shows the structure of the digital camera lens barrel to which the lens barrel concerning 2nd Embodiment is applied. It is a figure which shows the structure of the lens-barrel concerning 3rd Embodiment which implemented this invention suitably. It is a figure which shows the structure of the lens barrel using CCD with a narrow image pick-up element range. It is a figure which shows another structure of the lens barrel using CCD with a narrow image pick-up element range. It is a figure which shows another structure of the lens barrel using CCD with a narrow image pick-up element range.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st lens group 2 2nd lens group 3 3rd lens group 4 4th lens group 5 1st lens frame 6 2nd lens frame 7 Shutter 8 Fixed cylinder 9 1st rectilinear advance key 10 2nd rectilinear advance key 11 Inner cam 12 Second rotating cylinder 13 First rotating cylinder 14 Second zoom motor 15 Focus motor 16 Third lens frame 17 Fourth lens frame 18 Spring 19 Nut 19a End portion 21 Base 22 Main shaft 23 Sub shaft 100 Optical system unit 101 First 1st group 102 2nd group 103 3rd group 104 Lens frame cartridge 111 Lens barrel exterior parts 121, 127 CCD
124, 125 Outermost light beam 126 Light beam limiting member 128 Imaging element range 129, 133 Exterior part 130 Light beam limiting unit 131 Aperture shielding unit 132 Aperture shielding unit drive mechanism 201 Optical system unit receiver 202 Light source 203 Projection chart 204 XY Stage 205 Focus adjustment micro 206 Second group frame cartridge 207 Slide stage 208 Chucking portion 209 Arm portion 210 Second group frame clamp 300 Lens biasing member 400 Projection surface 1021 First sub lens group 1021a Concentric lens 1021b Center lens frame 1022 Second sub lens group 1025 Aperture

Claims (8)

A first lens group disposed on the subject side, a second lens group disposed on the imaging plane side with respect to the first lens group, and further on the imaging plane side with respect to the second lens group. A zoom lens barrel having an insertion / removal mechanism that retracts the second lens group in a direction perpendicular to the optical axis in a non-photographing state.
A zoom finder device interlocking with the first lens group;
The second lens group is retracted between the objective lens groups of the zoom finder device in a non-shooting state,
The urging member attached to the second lens group urges the second lens group not only in the direction orthogonal to the optical axis in the non-photographing state but also in the optical axis direction. Zoom lens barrel.   The zoom lens barrel according to claim 1, wherein the other end of the biasing member is attached to the third lens group.   The zoom lens barrel according to claim 1, wherein the third lens group is a focus lens.   4. The zoom lens barrel according to claim 3, wherein the first lens group, the second lens group, and the third lens group are driven by different motors to perform zooming and focusing.   5. The zoom lens barrel according to claim 1, wherein the biasing member biases the third lens group in a direction substantially parallel to the optical axis in a photographing state.   The insertion / removal mechanism inserts the second lens group onto the optical axis during the transition from the non-photographing state to the photographing state, and moves the second lens group during the transition from the photographing state to the non-photographing state. 6. The zoom lens barrel according to claim 1, wherein the zoom lens barrel is retracted from the optical axis.   A camera comprising the zoom lens barrel according to any one of claims 1 to 6.   A digital camera comprising the zoom lens barrel according to any one of claims 1 to 6.

Images