JP6780243B2 - Eccentricity adjustment structure and optical equipment - Google Patents

Description

The present invention relates to a technique for adjusting the eccentricity of an optical element such as a lens or a lens group incorporated in a lens barrel in the lens barrel.

The lens or lens group is orthogonal to the lens optical axis direction in order to obtain the imaging performance of the lens in the lens barrel provided integrally with the camera body or in the lens barrel independent of the camera body such as an interchangeable lens. A technique is known in which the position of the lens optical axis is adjusted, that is, the eccentricity is adjusted by moving the lens in parallel in the direction, and the lens or the lens group is fixed in the lens barrel after the eccentricity adjustment. Hereinafter, the lens or the lens group may be referred to as a lens.

Patent Document 1 describes a positioning screw member for adjusting the eccentricity of the lens frame, an elastic member such as a coil spring provided at a position facing the positioning screw member, and an optical axis in contact with the elastic member. An eccentricity adjusting technique having a fixing member that limits the amount of movement in the orthogonal direction is disclosed. Further, in Patent Document 2, eccentricity adjustment is performed using an eccentricity adjusting device, and after the adjustment, an adhesive is filled in a recess provided on the contact surface of a holding member for holding the lens to bond and fix the lens frame. The technology is disclosed. Patent Document 3 is a technique related to a varifocal lens, which will be described later.

Japanese Unexamined Patent Publication No. 2010-286681 Japanese Unexamined Patent Publication No. 8-327869 Japanese Unexamined Patent Publication No. 2012-73307

In the eccentricity adjusting technique of Patent Document 1, the eccentricity is adjusted and then fixed by a fixing member. However, since this fixing member is composed of a screw member, the friction torque when the fixing member is fastened is used. There is a problem that the lens frame rotates about the positioning screw member with respect to the plane orthogonal to the optical axis, and the fixing accuracy after adjustment is low.

In the eccentricity adjustment technique of Patent Document 2, since the lens frame is adhesively fixed to the lens barrel on the peripheral surface, when it becomes necessary to reassemble the lens and perform eccentricity adjustment again, the lens There is a problem that it is difficult to release the adhesion of the frame and disassemble the lens frame, it takes a lot of manpower, or it is difficult to reuse lens components such as the lens frame.

An object of the present invention is to provide an eccentricity adjusting structure that enhances the fixing accuracy of a lens after eccentricity adjustment and enables disassembly and reassembly of lens components when re-eccentricity adjustment is performed. is there.

The present invention includes a tubular member and an optical element built in the tubular member, and the optical element is moved in the tubular member on a plane orthogonal to the tubular axial direction to cause a bias of the optical element. An eccentric adjustment structure that adjusts the core, and has a fixing pin that is detachably provided at at least one location on the peripheral surface of the optical element and a pin fixing hole that is provided on the tubular member and a part of the fixing pin is inserted. The fixing pin is adhered to the pin fixing hole. In this bonded state, the optical element is fixed to the tubular member. In this case, an adhesive is provided which is injected into the pin fixing hole and adheres the fixing pin. Further, when the fixing pin breaks the adhesive state and is separated from the pin fixing hole to the outside of the tubular member , the optical element is configured to be movable with respect to the tubular member .

In the present invention, the fixing pin is provided on the circumferential direction of the three optical elements, pin fixing holes have preferably be provided in three places in the circumferential direction corresponding to the fixing pins. Further, it is preferable that the fixing pin is formed with an annular groove or a screw groove into which a release tool can be engaged.

As a preferable form of the eccentricity adjusting structure and the optical device of the present invention, a first adjusting screw for adjusting the position of the optical element in a predetermined first direction on a plane orthogonal to the cylinder axis and a second adjusting screw orthogonal to the first adjusting screw are used. A second adjusting screw that adjusts the position in the direction, a first urging spring that urges the optical element in the opposite direction of the first direction, and a second urging that urges the optical element in the opposite direction of the second direction. The form is provided with a force spring.

In this preferred embodiment, a movement restricting plate that restricts the optical element so as to be movable in the first direction or the second direction is provided. This movement control plate is configured to be movable in the second direction or the first direction with respect to the tubular member. Further, the movement control plate is formed in a semicircular ring shape corresponding to the tubular shape of the tubular member, and has a tubular shape with an engaging portion that is engaged with the optical element so as to be relatively movable in the first direction or the second direction. It includes an engaging portion that is movably engaged with the member in a second direction or a first direction.

According to the eccentricity adjusting structure and the optical device of the present invention, the fixing accuracy of the lens after the eccentricity adjustment can be improved by fixing the fixing pin attached to the optical element to the tubular member with an adhesive. it can. Further, by removing the fixing pin from the pin fixing hole while breaking the adhesive from the outside of the tubular member, it is possible to disassemble the optical element and reassemble it when the eccentricity adjustment is performed again.

A cross-sectional view of a lens barrel provided with the eccentricity adjusting structure of the present invention when wide. The reduced cross-sectional view of the lens barrel of FIG. 1 at the time of telephony. Partially disassembled perspective view of the second base cylinder and the optical elements attached to it. A partially disassembled perspective view of the third lens group, the movement control plate, and the second base cylinder as viewed from the front. A partially disassembled perspective view of the third lens group and the movement control plate as viewed from the rear. (A) is a rear view of the assembled state of the third lens group and the movement restricting plate, and (b) is a front view of the assembled state of the movement restricting plate and the second base cylinder. Sectional view in the direction perpendicular to the optical axis of the 3rd lens group and the 2nd base cylinder. (A) is a plan view of the fixing pin and the pin fixing hole as viewed from the outer diameter direction, and (b) is a cross-sectional view in the direction perpendicular to the optical axis. The same figure as FIG. 8 (b) of the modification of the fixing pin.

Next, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 show the upper half of a vertical cross-sectional view along the optical axis of a zoom lens barrel provided with an eccentricity adjusting structure as an example of the optical instrument of the present invention, and FIG. 1 shows a wide (short focal length). An enlarged sectional view at the time of (distance), and FIG. 2 is a reduced sectional view at the time of tele (long focal length). Each figure is in the state of the infinity focal position. This zoom lens barrel is composed of the first to fifth lens groups L1 to L5, and is configured as a varifocal zoom lens barrel that performs focusing at the same time as zooming. Each lens group L1 to L5 may be a single lens.

In FIG. 1, the fixed cylinder has a first fixed cylinder 1A and a second fixed cylinder 1B, and includes a mount portion 1C mounted on a camera body (not shown) on the back surface of the second fixed cylinder 1B. A zoom operation ring ZR for zooming (changing the focal length) is arranged on the outer circumference of the first fixed cylinder 1A, and a focus operation ring FR for focusing (focusing) is performed on the peripheral surface of the second fixed cylinder 1B. Are arranged so that the photographer can manually rotate each of them.

A zoom cam cylinder 2 is integrally formed on the inner circumference of the zoom operation ring ZR, and rotates around the optical axis (same as the cylinder axis of the lens barrel) around the outer circumference of the first fixed cylinder 1A together with the zoom operation ring ZR. Be manipulated. Further, a focus gear 3a is integrally formed on the focus operation ring FR, and a gear mechanism for which description is omitted is meshed with the focus gear 3a, and the second gear mechanism is interposed via an output member 3b of the gear mechanism. A focus linkage lever 3 extended in the optical axis direction is connected to the inner diameter region of the fixed cylinder 1B, and the focus linkage lever 3 operates a varifocal compensation mechanism described later.

On the inner circumference of the first fixed cylinder 1A, a first base cylinder 4A is internally supported by a guide member (not shown in the drawing) so as to be movable in the optical axis direction inside the first fixed cylinder 1A. A cam pin 4a protrudes radially from the outer peripheral surface of the first base cylinder 4A, and the cam pin 4a penetrates a linear guide groove 1a in the optical axis direction provided in the first fixed cylinder 1A and the zoom cam cylinder 2 The cam is engaged with the cam groove 2a provided in the above. Therefore, when the zoom cam cylinder 2 is rotated by the zoom operation ring ZR, the first base cylinder 4A is moved in the optical axis direction by the cam engagement between the cam groove 2a and the cam pin 4a.

A base inner cylinder 4B is arranged at the inner peripheral position of the first base cylinder 4A, and is configured to be integrally rotated around the optical axis with the first base cylinder 4A. Between the first base cylinder 4A and the base inner cylinder 4B, a first lens cylinder 5 provided integrally with the first lens frame LF1 of the first lens group L1 is provided in the optical axis direction with respect to the first base cylinder 4A. It is fitted so that it can be moved. Further, at the inner peripheral position of the base inner cylinder 4B, a first sub-zoom cam cylinder 6A that is integrated with the base inner cylinder 4B in the optical axis direction and is rotatable around the optical axis is installed. The first sub-zoom cam cylinder 6A is connected to the zoom cam cylinder 2 by a connecting means (not shown in FIG. 1), rotates integrally with the zoom cam cylinder 2, but is configured to be relatively movable in the optical axis direction.

The first lens cylinder 5 has a cam pin 5a projecting in the inner diameter direction, and the cam pin 5a penetrates a linear guide groove in the optical axis direction provided on the base inner cylinder 4B and does not appear in the drawing. 1 The sub-zoom cam cylinder 6A is fitted into a cam groove not shown in the drawing and is engaged with the cam. Therefore, when the zoom cam cylinder 2 is rotated and the first sub-zoom cam cylinder 6A is rotated integrally with the zoom cam cylinder 2, the first lens cylinder 5, that is, the first lens group L1 is moved by the optical axis due to the cam engagement. ..

At the inner diameter position of the rear end side region of the first base cylinder 4A, a second base cylinder 4C which is connected to the first base cylinder 4A and rotated integrally with the first base cylinder 4A is provided. .. A third lens group L3, a fourth lens group L4, and a fifth lens group L5 are assembled to the second base cylinder 4C. The configuration of the second base cylinder 4C will be described later.

The second lens group L2 is a lens for performing focusing compensation, and is a varifocal that is supported by the second lens frame LF2 and whose optical axis is moved by the rotation of the first sub-zoom cam cylinder 6A and the rotation of the focus operation ring FR. It has a compensation mechanism.

This varifocal compensation mechanism is a mechanism for adjusting the position of the second lens group L2 in the optical axis direction in response to the zooming operation in order to compensate for the change in the focus point due to the zooming operation. Since there is little relation between, the explanation is simplified here. As the varifocal compensation mechanism, for example, the structure described in Patent Document 3 can be adopted.

That is, the varifocal compensation mechanism includes a tubular main lens frame 7A and a sub lens frame 7B separated in the optical axis direction, and the second lens frame LF2 of the second lens group L2 is supported by the main lens frame 7A. Has been done. The main lens frame 7A and the sub lens frame 7B are integrated in the rotation direction, but are relatively movable in the optical axis direction within a predetermined length range. Further, when the first sub-zoom cam cylinder 6A is rotated, the sub-lens frame 7B is moved in the optical axis direction.

A four-camu camu cylinder 8 having a camu groove having a required shape is installed on the inner peripheral side of the sub-lens frame 7B. In this focus cam cylinder 8, the connecting pin 8a is engaged with the guide groove 6a in the optical axis direction provided in the first sub-zoom cam cylinder 6A, and when the first sub-zoom cam cylinder 6A rotates, it rotates integrally, but the first sub-zoom cam It is movable in the optical axis direction independently of the cylinder 6A.

A lens frame moving cylinder 9 is installed on the inner peripheral side of the four camu camu cylinder 8. The lens frame moving cylinder 9 is integrally rotatable in the optical axis direction and is rotatable relative to the main lens frame 7A. The tip of the focus linkage lever 3 connected to the focus operation ring FR is interpolated in a part of the lens frame moving cylinder 9 in the optical axis direction. Due to this interpolation, the lens frame moving cylinder 9 is integrally rotated when the focus linkage lever 3 is rotated, but the optical axis can be moved independently of the focus linkage lever 3 in the optical axis direction.

The cam pin 7a of the auxiliary lens frame 7B is cam-engaged with the cam groove 8b provided in the four camu camu cylinder 8. Further, a cam pin 9a provided on the outer peripheral surface of the lens frame moving cylinder 9 is cam-engaged with the cam groove 8b.

FIG. 3 is a partially exploded perspective view of the structure including the second base cylinder 4C and the optical element attached to the second base cylinder 4C. Here, the third to fifth lens groups L3 to L5 and the aperture mechanism 11 are provided as optical elements. Three connecting pieces 10 for being connected to the first base cylinder 4A are formed so as to project in the outer diameter direction at three locations in the circumferential direction of the outer peripheral surface of the second base cylinder 4C. It is moved in the optical axis direction integrally with the first base cylinder 4A via the above. In addition, guide grooves 4b extending in the optical axis direction are radially penetrated at three locations in the circumferential direction of the second base cylinder 4C, and cam pins 12 of the fourth lens group L4 shown in FIG. 1 and described later are radially oriented. It is designed to be inserted.

A second sub-zoom cam cylinder 6B is arranged at the outer peripheral position of the second base cylinder 4C, and is rotatably supported by the second base cylinder 4C. The second sub-zoom cam cylinder 6B is connected to the first sub-zoom cam cylinder 6A by a connecting means not shown in FIG. 1, and is configured to rotate integrally with the first sub-zoom cam cylinder 6A.

A diaphragm mechanism 11 is internally supported at the front end of the second base cylinder 4C. The diaphragm mechanism 11 has a pressing ring 11a having a predetermined opening diameter and attached to the front end portion of the second base cylinder 4C, and has a plurality of diaphragm blades inside the pressing ring 11a. The diaphragm blade portion 11b (see FIG. 1) is incorporated. An annular diaphragm rotary ring 11c is engaged with the diaphragm blade portion 11b from the rear, and the diaphragm rotary ring 11c is engaged with a diaphragm drive member not shown in the figure. When the diaphragm rotating ring 11c is rotated by the diaphragm driving member, the opening diameter of the diaphragm opening formed by the diaphragm blade portion 11b is changed.

In the region on the rear side of the aperture mechanism 11, the third lens group L3 is internally supported by the third lens frame LF3. The third lens group L3 can be eccentricly adjusted with respect to the second base cylinder 4C, and after the eccentricity adjustment, is fixed to the second base cylinder 4C and has an optical axis integrated with the second base cylinder 4C. It is designed to move. The details of the third lens group L3 will be described later.

The fourth lens group L4 is supported by the fourth lens frame LF4 and is interpolated in the second base cylinder 4C so as to be movable in the optical axis direction. The fourth lens frame LF4 is provided with a cam pin 12 projecting in the radial direction (see FIG. 1), and the cam pin 12 is penetrated through a guide groove 4b provided in the second base cylinder 4C, and the first 2 It is engaged with the cam groove 6b formed in the sub-zoom cam cylinder 6B. As a result, when the second sub-zoom cam cylinder 6B is rotated, the fourth lens group L4 is moved by the optical axis due to the cam engagement.

The fifth lens group L5 can be eccentricly adjusted with respect to the second base cylinder 4C by a normal eccentricity adjusting structure, and after the eccentricity is adjusted, the second base cylinder 4C is subjected to fixing means for which description is omitted. It is fixed. Since each of the operations of eccentricity adjustment and fixing of the fifth lens group L5 can be easily performed from the rear end side of the second base cylinder 4C, the eccentricity adjustment structure of the present invention is not provided here.

The eccentricity adjusting structure of the present invention is provided in the third lens group L3, and the third lens frame LF3 of the third lens group L3 is connected to the movement restricting plate 13 adjacent to the third lens group L3 in the optical axis direction. 2 The interior is supported by the base cylinder 4C. Since the third lens group L3 is housed in a region sandwiched by the diaphragm mechanism 11 and the fourth lens group L4 in the optical axis direction inside the second base cylinder 4C, eccentricity adjustment and fixed support work Is not always easy, and the eccentricity adjusting structure of the present invention is applied.

FIG. 4 is a partially exploded perspective view of the second base cylinder 4C, the third lens group L3, and the movement restricting plate 13, and FIG. 5 shows the third lens group L3 and the movement restricting plate 13 opposite to each other. It is a partially disassembled perspective view seen from the direction (rear). The movement restricting plate 13 is formed of a substantially semicircular annular plate material, and has a length extending in the first direction (± Y direction in the figure) at each end position in the circumferential direction and at the central position in the circumferential direction. Three first guide holes 13a composed of holes are opened. Further, at the same both end positions, two second guide holes 13b formed of elongated holes extending in the second direction (± X direction in the figure) orthogonal to the first direction are opened. These first guide holes 13a and second guide holes 13b are configured as engaging portions in the present invention.

FIG. 6A is a rear view of the state in which the movement restricting plate 13 is assembled to the third lens group L3, and the rear surface of the third lens frame LF3 is provided in the first guide hole 13a of the movement restricting plate 13. The three first protrusions 14a provided in the lens and projecting in the optical axis direction are engaged with each other in the fitted state. As a result, the third lens frame LF3 can move in the first direction (± Y direction) with respect to the movement restricting plate 13 by a minute dimension.

FIG. 6B is a front view of the state in which the movement restricting plate 13 is assembled to the second base cylinder 4C, and the second guide hole 13b of the movement restricting plate 13 is provided in the second base cylinder 4C. The two second protrusions 14b that are projected in the optical axis direction are engaged with each other in the fitted state. As a result, the movement restricting plate 13 can move relative to the second base cylinder 4C in the second direction (± X direction) by a minute dimension.

By assembling the second base cylinder 4C, the third lens group L3, and the movement restricting plate 13 in this way, the third lens frame LF3, that is, the third lens group L3 passes through the movement restricting plate 13. It is movable relative to the second base cylinder 4C in the first direction and the second direction, respectively.

Here, since the movement restricting plate 13 is supported by the third lens frame LF3 at the first guide holes 13a and the first protrusions 14a at three locations in the circumferential direction, even when the movement restricting plate 13 is formed of a thin plate member. , The bending deformation that tends to occur in the semicircular annular plate member is prevented, and the movement restricting plate 13 is supported by the first guide hole 13a and the first protrusion 14a with respect to the second base cylinder 4C, and the third lens group L3 is moved. The reliability of guidance when doing this is improved.

FIG. 7 is a cross-sectional view of the third lens group L3 in the direction perpendicular to the optical axis. A portion that divides the outer peripheral surface of the third lens frame LF3 into four equal parts in the circumferential direction, that is, the first direction (± Y direction) and the second direction (± Y direction) in which the third lens group L3 is relatively moved by the movement restricting plate 13. Each region in the circumferential direction corresponding to the X direction) is formed as a flat surface 15 (15a to 15d) along the tangential direction. Of these flat surfaces 15, two flat surfaces adjacent to each other in the circumferential direction, that is, two flat surfaces 15a and 15b perpendicular to the center of the third lens frame, are spring holes 16a and 16b toward the inner diameter, respectively. Is open.

Inside these spring holes 16a and 16b, a first urging spring 17a and a second urging spring 17b made of coil springs are internally provided in the radial direction, and the respective urging springs 17a and 17b are on the outer diameter side. The end portion is in a state of slightly protruding from the outer peripheral surface of the third lens frame LF3. Further, spring contact portions 23a and 23b formed of flat surfaces in the tangential direction are formed at two locations on the inner peripheral surface of the second base cylinder 4C corresponding to the urging springs 17a and 17b. The ends of the force springs 17a and 17b on the outer diameter side are brought into contact with each other in the radial direction.

Pin holes 18 (18a, 18b, 18c) are opened in the locations where the outer peripheral surface of the third lens frame LF3 is divided into three equal parts in the circumferential direction, respectively, in the inner diameter direction. These three pin holes 18 are provided at positions that do not interfere with the two spring holes 16a and 16b and the two adjusting screw contact portions 15c and 15d, and each pin hole 18 is provided with a fixing pin 19 (from the outer diameter direction). 19a, 19b, 19c) are closely interpolated. These fixing pins 19 are formed longer than the depth of the pin holes 18, and when they are inserted into the pin holes 18, the ends on the outer diameter side protrude in the radial direction from the outer peripheral surface of the third lens frame LF3. ing.

In the peripheral surface of the second base cylinder 4C, radial holes 20c and 20d are penetrated at two locations corresponding to the adjusting screw contact portions 15c and 15d of the third lens frame LF3, and the holes 20c and 20d are formed. The internal screw collars 21c and 21d having thread grooves formed on the inner peripheral surface are press-fitted into the lens. The first adjusting screw 22c is screwed into one inner screw collar 21c from the outer diameter direction, and the second adjusting screw 22d is screwed into the other inner screw collar 21d from the outer diameter direction. Of the four flat surfaces 15 on the outer peripheral surface of the third lens frame LF3, the flat surfaces 15c and 15d not provided with the spring holes are configured as adjusting screw contact portions, and the internal screw collar 21c. The inner diameter ends of the adjusting screws 22c and 22d screwed into the adjustment screws 22c and 21d are brought into radial contact with the adjusting screw contact portions 15c and 15d, respectively.

Further, on the peripheral surface of the second base cylinder 4C, pin fixing holes 24 (24a, 24b, 24c) are radially provided at three locations in the circumferential direction corresponding to the three pin holes 18 of the third lens frame LF3. It is open. These pin fixing holes 24 have an opening area larger than that of the pin holes 18, and are opened here as rectangular pin fixing holes. As a result, the three pin holes 18 and the fixing pins 19 inserted therein are exposed to the outer peripheral surface side of the second base cylinder 4C through the pin fixing holes 24, respectively. Further, the end portion of the fixing pin 19 on the outer diameter side is arranged in the pin fixing hole within a range not protruding from the outer peripheral surface of the pin fixing hole 24.

The operation of the lens barrel having the above configuration will be described with reference to FIGS. 1 and 2 again. First, zooming will be described. When the zoom operation ring ZR is rotated in the tele direction from the wide state of FIG. 1, the zoom cam cylinder 2 is rotated, and the first base cylinder 4A cam-engaged with the zoom cam cylinder 2 is moved forward by the optical axis. At the same time, the first and second sub-zoom cam cylinders 6A and 6B connected to the zoom cam cylinder 2 are rotated. By the rotation of the first sub-zoom cam cylinder 6A, the first lens group L1 is moved by the optical axis together with the first lens frame LF1 with which the cam is engaged.

At the same time, the sub lens frame 7B of the second lens group L2 cam-engaged with the first sub-zoom cam cylinder 6A is moved forward by the optical axis, and the main lens frame 7A engaged with the sub lens frame 7A is also moved in the optical axis direction. It is moved, and the second lens group L2 is moved in the optical axis direction. The third lens group L3 and the fifth lens group L5 are moved in the optical axis direction integrally with the second base cylinder 4C which is moved along with the movement of the first base cylinder 4A in the optical axis direction. Further, the rotation of the second sub-zoom cam cylinder 6B, which is rotated integrally with the first sub-zoom cam 6A, causes the fourth lens group L4 to be moved by the optical axis together with the fourth lens frame LF4 that is cam-engaged with the second sub-zoom cam cylinder 6B. As a result, it will be zoomed to the tele state shown in FIG.

As described above, during zooming, the first to fifth lens groups are moved by the optical axis to perform the zooming operation, and at the same time, the focusing operation is also performed. In this focusing operation, the second lens group L2 is moved by the optical axis, but since it is a varifocal lens, it is necessary to operate the focus operation ring FR to perform focusing. At this time, the varifocal compensation mechanism provides varifocal compensation that keeps the rotation angle of the focus operation ring FR constant regardless of the difference in shooting distance.

Since the operation of this varifocal compensation mechanism is substantially the same as the operation described in Patent Document 3 described above, it will be briefly described here. The focus cam 8 is integrally rotated by the rotation 6A of the first sub-zoom cam cylinder during zooming. At this time, the sub-lens frame 7B of the focus lens group L2 is moved by the first sub-zoom cam cylinder 6A on the optical axis, and at the same time, the focus cam cylinder 8 is moved by the optical axis by a predetermined distance.

When the focus operation ring FR is rotated in this state, the focus linkage lever 3 is rotated via the focus gear 3a and the output member 3b, and the main lens frame moving cylinder 9 connected to the focus coupling lever 3 is rotated and at the same time is rotated by a predetermined distance. It is moved in the optical axis direction. By the movement of the main lens frame moving cylinder 9, the main lens frame 7A is moved in the optical axis direction. By designing the cam groove 8b provided in the focus cam cylinder 8 to a required shape, the amount of movement of the main lens frame moving cylinder 9 in the optical axis direction is adjusted, and the second lens group L2 supported by this is adjusted. Is moved by the optical axis and focusing is performed. As a result, focusing at a constant rotation angle of the focus operation ring FR can be realized even in a varifocal lens.

When assembling the lens barrel having the above configuration, the sub-assy in which the third lens group L3, the fourth lens group L4, and the fifth lens group L5 are incorporated in the second base cylinder 4C, and the second sub-zoom cam cylinder 6B is further incorporated. The structure is constructed, and this sub-assy structure is incorporated in the lens barrel.

When the third lens group L3 is incorporated into the second base cylinder 4C, as shown in FIG. 7, the third lens group L3 is the outer diameter side ends of the two urging springs 17a and 17b of the third lens frame LF3. The portion is brought into contact with the spring contact portions 23a and 23b on the inner peripheral surface of the second base cylinder 4C. At the same time, the inner diameter side ends of the first adjusting screw 22c and the second adjusting screw 22d of the second base cylinder 4C are brought into contact with the two adjusting screw contact portions 15c and 15d of the third lens frame LF3, respectively. As a result, the third lens frame LF3 is provided with the first and second adjusting screws 22c and 22d and the first and second urging springs 17a and 17b at four locations in the circumferential direction in the first direction and the second direction. It is held in a state of being sandwiched in each radial direction of the lens.

When adjusting the eccentricity of the third lens group L3 held in the second base cylinder 4C in this way, the first adjustment screw is used from the outside of the second base cylinder 4C with a jig such as a screwdriver (screwdriver). Rotate the 22c and the second adjusting screw 22d. By screwing the first adjusting screw 22c in the inner diameter direction, the third lens group L3 is moved in the second direction (−X direction) while bending the first urging spring 17a. On the contrary, by screwing the first adjusting screw 22c in the outer diameter direction, the third lens group L3 is moved in the opposite second direction (+ X direction) by the spring force of the first urging spring 17a. At this time, the third lens group L3 is guided in the second direction (± X direction) with respect to the second base cylinder 4C together with the movement restricting plate 13 by the second guide hole 13b of the movement restricting plate 13.

Similarly, by screwing the second adjusting screw 22d in the inner diameter direction with a jig, the third lens group L3 is moved in the first direction (−Y direction) while bending the second urging spring 17b. On the contrary, by screwing the second adjusting screw 22d in the outer diameter direction, the third lens group L3 is moved in the opposite first direction (+ Y direction) by the spring force of the second urging spring 17b. At this time, the third lens group L3 is guided in the first direction (± Y direction) with respect to the movement restricting plate 13, that is, with respect to the second base cylinder 4C by the first guide hole 13a of the movement restricting plate 13. .. As described above, the position of the third lens group L3 is adjusted in the first direction (± Y direction) and the second direction (± X direction) with respect to the second base cylinder 4C to perform eccentricity adjustment.

When the eccentricity adjustment of the third lens group L3 is completed, the fixing pins 19 are inserted in the radial direction from the outside of the second base cylinder 4C through the three pin fixing holes 24, and each pin hole 18 of the third lens frame LF3 is inserted. To fit in. Each fixing pin 19 is interpolated and supported in close contact with the pin hole 18. At this time, the end portion of each fixing pin 19 on the outer diameter side protrudes from the outer peripheral surface of the third lens frame LF3 and is located inside the pin fixing hole 24.

Therefore, as shown in FIGS. 8A and 8B, a plan view of one pin fixing hole 24a as viewed from the outer diameter direction and a cross-sectional view in the direction perpendicular to the optical axis are shown, respectively. The adhesive c is injected into each of the three pin fixing holes 24a from the outside of the 4C, and the end portion of the fixing pin 19a on the outer diameter side is adhesively fixed to the inside of the pin fixing hole 24a. The third lens group L3 is fixedly supported with respect to the second base cylinder 4C by adhesively fixing the fixing pins 19 (19a to 19c) in the three pin fixing holes 24 (24a to 24c), respectively. Therefore, it is stably fixed in the eccentric adjusted state.

Here, the fixing pin 19 is formed with an annular groove t on the peripheral surface of the end portion facing the outer diameter side, as in the fixing pin 19a of FIG. 8B. The annular groove t is provided at a position where it is exposed to the outside through the pin fixing hole 24 when it is inserted into the pin fixing hole 24. Further, in this embodiment, the annular groove t is embedded by the adhesive c.

After the third lens group L3 is eccentrically adjusted and fixed to the second base cylinder 4C, the eccentricity of the fifth lens group L5 is adjusted and fixed to the second base cylinder 4C. As described above, since the fifth lens group L5 is exposed from the rear end side of the second base cylinder 4C, eccentricity adjustment and fixing can be easily performed.

When the eccentricity adjustment of the third lens group L3 is required again based on the result of the eccentricity adjustment of the fifth lens group L5, or when the eccentricity adjustment of the third lens group L3 is required again for maintenance. In this case, as shown by the chain line in FIG. 8B, the tip of the tool T such as a driver is inserted into the pin fixing hole 24a, and the tip is inserted into the annular groove of the fixing pin 19a while breaking the adhesive state of the adhesive c. Engage with t. After engaging, the driver T is leveraged to forcibly remove the fixing pin 19a from the pin fixing hole 24a and the pin hole 18a. By forcibly pulling out the three fixing pins 19a to 19c in this way, the fixing of the third lens group L3 is released. Therefore, as described above, the eccentricity adjustment can be performed again by the first and second adjusting screws 22c and 22d. After adjusting the eccentricity, the adhesive may be injected into the pin fixing holes 24a to 24c again to fix the pin.

In this way, when adjusting the eccentricity of the third lens group L3 again, it is sufficient to break the adhesive state of the adhesive c injected into the pin fixing hole 24 and forcibly pull out the fixing pin 19, so that it is relatively relatively possible. The fixed state of the third lens group L3 can be easily released. Therefore, without damaging the third lens frame LF3, the second base cylinder 4C, the first and second urging springs 17a and 17b, and the adjusting screws 22c and 22d, or the fixing pin 19 (19a to 19c). It is also possible to reuse the lens, and the eccentricity adjustment can be realized easily and at low cost.

Here, the fixing pin 19 may be configured as an internal thread pin. FIG. 9 shows an example thereof. The inner screw pin 19A has a cylindrical outer peripheral surface and a female screw s is formed on the inner peripheral surface. The third lens is formed by using the inner screw pin 19A in the same manner as the fixing pin of the above embodiment, that is, by injecting the adhesive c into the pin fixing hole 24a and adhering the inner screw pin 19A after inserting the pin hole 18a. The group L3 can be fixedly supported by the second base cylinder 4C.

When adjusting the eccentricity again, the tool T1 having a threaded portion is screwed from the end of the internal screw pin 19A to the female screw s, and the tool T1 is pulled in the outer diameter direction on the tool T1 to remove the adhesive c. Forcibly remove the internal screw pin 19A from the pin fixing hole 24a and the pin hole 18a while breaking the bonded state. As a result, the fixation of the third lens group L3 is released, and the eccentricity adjustment can be performed again. Since the internal screw pin 19A is connected to the jig T1 by screwing, it can be reliably and easily pulled out.

In the above embodiment, the third lens group L3 is eccentrically adjusted by the first and second urging springs 17a and 17b and the adjusting screws 22c and 22d. Therefore, these urging springs 17a and 17b and the adjusting screw 22c, Even with 22d, it is possible to hold the adjustment position of the third lens group L3 with a certain degree of intensity. Therefore, even if the fixing pin 19 is provided at at least one position on the peripheral surface of the third lens frame LF3, the third lens group L3 can be fixedly supported with respect to the second base cylinder 4C. However, in order to prevent the third lens group L3 from tilting with respect to the plane orthogonal to the optical axis and to secure stable fixed support, the fixing pins 19 are arranged at two locations different in the circumferential direction. It is preferable to perform fixing support with two fixing pins or three fixing pins arranged at three different places as in the embodiment.

In the embodiment described above, an example in which the present invention is applied to a zoom lens barrel having a 5-group lens configuration is shown, but the present invention is not limited to this lens barrel, and a lens that requires eccentricity adjustment. The present invention can be applied to any lens barrel or optical device provided with a group. That is, the present invention can be applied to optical devices such as interchangeable lens barrels, lens-integrated cameras, projectors, telescopes, and binoculars, which have a structure in which a lens group is built in a tubular member to adjust eccentricity.

The fixing pin in the present invention is not necessarily limited to the shape described in the embodiment, and can be attached to the peripheral surface of the optical element incorporated in the tubular member in a radial direction, and has an outer diameter thereof. Any structure may be used as long as the side end portion can be adhesively fixed in the opening provided in the tubular member. Therefore, it is also possible to configure the fixing pin with a screw member and screw it into the peripheral surface of the optical element in the radial direction.

1A 1st fixed cylinder 1B 2nd fixed cylinder 1C Lens mount 2 Zoom cam cylinder 3 Focus linkage lever 4A 1st base cylinder 4B Base inner cylinder 4C 2nd base cylinder (cylindrical member)
5 1st lens cylinder 6A 1st sub zoom cam cylinder 6B 2nd sub zoom cam cylinder 7A Main lens frame 7B Sub lens frame 8 Focus cam cylinder 9 Main lens frame moving cylinder 11 Aperture mechanism (optical element)
13 Movement control plates 13a, 13b Guide holes (engagement part)
14a, 14b protrusion (engagement part)
17a, 17b Biasing spring 18 (18a-18c) Pin hole 19 (19a-19c) Fixing pin 22c, 22d Adjusting screw 24 (24a-24c) Pin fixing hole t Circular groove s Thread groove c Adhesive T, T1 Tool L1 ~ L5 1st to 5th lens groups (optical elements)
ZR Zoom operation ring FR Focus operation ring

Claims (12)

The eccentricity of the optical element is adjusted by moving the optical element in the tubular member on a plane orthogonal to the tubular axial direction, including the tubular member and the optical element contained in the tubular member. In the eccentricity adjusting structure to be performed, a fixing pin provided detachably at at least one position on the peripheral surface of the optical element and a pin fixing hole provided on the tubular member into which a part of the fixing pin is inserted are provided. The fixing pin is adhered to the pin fixing hole by an adhesive, and in the bonded state, the optical element is fixed to the tubular member, the bonded state is broken, and the fixing pin is moved from the pin fixing hole to the cylinder. An eccentricity adjusting structure, characterized in that the optical element is movable with respect to the tubular member when it is separated from the outside of the shaped member . The eccentricity adjusting structure according to claim 1, wherein the fixing pins are provided at three locations in the circumferential direction of the optical element, and the pin fixing holes are provided at three locations in the circumferential direction corresponding to the fixing pins. The eccentricity adjusting structure according to claim 1 or 2, wherein the fixing pin is formed with an annular groove or a screw groove to which a detaching jig can be engaged. A first adjusting screw that adjusts the position of the optical element in a predetermined first direction on a plane orthogonal to the tubular axis, a second adjusting screw that adjusts the position in a second direction orthogonal to the first adjusting screw, and the optical element. Any of claims 1 to 3 comprising a first urging spring for urging the optical element in the opposite direction of the first direction and a second urging spring for urging the optical element in the opposite direction of the second direction. Eccentricity adjustment structure described in Crab. A movement restricting plate for restricting the optical element so as to be movable in the first direction or the second direction is provided, and the movement restricting plate is restricted to be movable in the second direction or the first direction with respect to the tubular member. The eccentricity adjusting structure according to claim 4, which has the same configuration. The movement restricting plate is formed in a semicircular ring corresponding to the tubular shape of the tubular member, and is engaged with an engaging portion that is movably engaged with the optical element in the first direction or the second direction. The eccentricity adjusting structure according to claim 5, further comprising an engaging portion that is movably engaged with the tubular member in the second direction or the first direction. The lens includes a base cylinder provided in the lens barrel and a lens group built in the base cylinder, and the lens group is moved in the base cylinder on a plane orthogonal to the optical axis direction of the lens barrel. An eccentricity adjusting structure for adjusting the eccentricity of the group, in which a fixing pin provided detachably at at least one position on the peripheral surface of the lens group and a part of the fixing pin provided on the base cylinder are inserted. The fixed pin is attached to the pin fixing hole, and in the bonded state, the lens group is fixed to the base cylinder, the bonded state is broken, and the pin fixing hole is attached to the outside of the base cylinder. An eccentricity adjusting structure characterized in that the lens group is movable with respect to the base cylinder when the lens group is detached from the base cylinder . A base cylinder provided in an optical device and an optical element built in the base cylinder are included, and the optical element is moved in the base cylinder on a plane orthogonal to the optical axis direction to position the optical axis of the optical element. An optical device that adjusts the position of the optical element with respect to the optical element, which is provided with a detachably provided fixing pin at at least one position of the optical element and a pin fixing hole provided on the base cylinder into which a part of the fixing pin is inserted. the fixing pin is adhered to the pin fixing hole, the adhesive state wherein the optical element is fixed to the base tube, said optical when disengaged from the pin fixing hole to the outside of the base tube by breaking the bonding status An optical device characterized in that the element is movable with respect to the base cylinder . The first and second adjusting screws that adjust the position of the optical element in the Y direction on the plane orthogonal to the optical axis and the X direction orthogonal to the optical element, and the optical element in the Y direction and the X direction. The first and second urging springs and a movement restricting plate for restricting the optical element so as to be movable in the X direction are provided, and the movement restricting plate restricts the optical element to be movable in the Y direction with respect to the base cylinder. The optical device according to claim 8, which is configured to be the same. The movement restricting plate is formed in a semicircular ring extending around the optical axis, and the optical element and the base cylinder move at three locations, both ends in the extension direction and an intermediate portion in the extension direction. The optical device according to claim 9, which is configured to regulate the above. The optical device according to claim 10, wherein the movement restricting plate restricts the movement of the optical element or the base cylinder at the intermediate portion and restricts the movement of the base cylinder or the optical element at both ends thereof. An optical device having the eccentricity adjusting structure according to any one of claims 1 to 7.

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