JP2021021802A - Diaphragm device and lens device and imaging device including the same - Google Patents

Abstract

To provide a diaphragm device which enables a photographer to successively adjust the size of an opening and switch between the circular and elliptical shapes of an opening in accordance with desired blurring effects at imaging time.SOLUTION: Provided is a diaphragm device comprising: a plurality of diaphragm blades each formed with a rotation center pin and a drive pin; a blade support part for supporting the diaphragm blades so as to be rotatable around the rotation center pin of each of the diaphragm blades; and a cam member having a first cam groove which the drive pin of each of the diaphragm blades engages with. The blade support part is composed of at least two or more members such as a first blade support member incapable of rotating round an optical axis and a second blade support member capable of rotating around the optical axis. The rotation center pins of the diaphragm blades engage with at least one of the engagement parts provided on the first or the second blade support member, and the opening shape is changed from a first shape to a second shape as the second blade support part rotates around the optical axis.SELECTED DRAWING: Figure 7

Description

The present invention relates to a diaphragm device used in a lens device for photography, and more particularly to a diaphragm device in which the aperture shape of the diaphragm device is switched, a lens device having the same, and an imaging device.

Conventionally, a plurality of diaphragm blades equipped with a rotation axis are arranged at equal angular intervals on the same circumference, and the size of the opening formed by the overlap of the inner edges of the diaphragm blades due to the rotation of the diaphragm blades around the rotation axis. A diaphragm device that changes the speed is known.

The aperture opening shape affects the goodness of the bokeh around the main subject in the captured image, and generally a beautiful blurred image can be obtained. Therefore, a diaphragm aperture shape close to a circle is required. On the other hand, there are also photographers who want a unique elliptical bokeh image of an anamorphic lens.

Here, regarding switching between a circular and an elliptical aperture shape according to a blurred image that the photographer wants to obtain at the time of photographing by using one photographing device, a plurality of aperture opening shapes are selected as shown in Patent Document 1. The structure has been proposed.

Japanese Unexamined Patent Publication No. 04-269727

However, since the aperture shape switching structure disclosed in Patent Document 1 constitutes a diaphragm opening having a plurality of aperture shapes as dedicated shapes, it hinders the miniaturization of the photographing apparatus. .. Further, during shooting of a moving image, if the opening shape is changed, the switching portion is once opaque to light, so that there is a problem that the size of the opening cannot be changed continuously.

Therefore, an object of the present invention is to provide an aperture device capable of continuously changing the size of an aperture with one aperture device and switching the aperture shape between a circular shape and an elliptical shape, and a lens device and a photographing device having the same. To do.

In order to achieve the above object, the diaphragm device according to the present invention is
A plurality of diaphragm blades on which a rotation center pin and a drive pin are formed, a blade support portion that rotatably supports the diaphragm blades with the rotation center pin of each of the diaphragm blades as the rotation center, and the drive of each of the diaphragm blades. In a diaphragm device comprising a cam member having a first cam groove with which a pin engages.
The blade support portion is composed of at least two or more members, a first blade support member that cannot rotate about the optical axis and a second blade support member that can rotate about the optical axis. The rotation center pin is engaged with at least one of the engaging portions provided on the first blade supporting member and the second blade supporting member, respectively, and the second blade supporting portion is optical. It is characterized in that the opening shape changes from the first shape to the second shape by rotating about the axis.

According to the present invention, there is provided an aperture device capable of continuously adjusting the size of an aperture and switching between a circular and elliptical aperture shape according to the effect of bokeh desired at the time of photographing. realizable.

Side sectional view of the drawing device of the first embodiment Partial fraction decomposition perspective view of the diaphragm device of the first embodiment Aperture index notation of the lens device of the first embodiment A substantially circular opening shape when the drawing device of the first embodiment is opened. Approximately circular opening shape when the drawing device of the first embodiment has a small drawing Approximately elliptical opening shape when the drawing device of the first embodiment is opened Approximately elliptical opening shape at the time of small drawing of the drawing device of the first embodiment Side sectional view of the drawing device of the second embodiment Partial fraction decomposition perspective view of the diaphragm device of the second embodiment Aperture index notation of the lens device of the second embodiment A substantially circular opening shape when the drawing device of the second embodiment is opened. Approximately elliptical opening shape when the drawing device of the second embodiment is opened

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

A side sectional view of the drawing device of this embodiment is shown in FIG. Further, FIG. 2 is a partially decomposed perspective view showing the internal structure of the diaphragm device.

The aperture device 2 is a part of the lens device 1, and the lens device 1 includes a lens group such as a focus unit, a zoom unit, and a relay unit (not shown). In FIG. 1, the left side in the drawing is the subject side, and the lens device 1 is connected to an imaging device (not shown) on the right side in the drawing at the time of shooting.

As shown in FIG. 1, the diaphragm device 2 is composed of a diaphragm blade support cylinder 10, a diaphragm blade support plate 11, a cam plate 12, two types of holding washers 13 and 14, and two types of diaphragm blades 15 and 16.

In both of the first diaphragm blade 15 and the second diaphragm blade 16, the rotation center pins 15a and 16a are convexly provided on the surface on the subject side, and the drive pins 15b and 16b are convex on the surface on the facing image pickup device side. It is installed. These two types of diaphragm blades have the same shape of the plate portions 15c and 16c, and differ only in the lengths of the convex rotation center pins 15a and 16a, and the second diaphragm blades are larger than the rotation center pins 15a of the first diaphragm blade 15. The rotation center pin of 16a is longer. The inner edges of the plate portions 15c and 16c are formed by an arc having a radius larger than the open opening diameter of the drawing device 2.

The diaphragm blade support plate 11 can smoothly rotate with respect to the diaphragm blade support cylinder 10, and the movement in the optical axis direction is restricted by the first presser washer 13.

The diaphragm blade support cylinder 10 is provided with 12 holes on the same circumference, for example, at equal intervals. The two holes located above and the two holes located below are insertion holes 10a having a hole diameter larger than the diameter of the rotation center pin 16a, and the other eight holes have a hole diameter of the rotation center pin. The engagement hole 10b is substantially equal to the diameter of 15a. Eight first diaphragm blades 15 are incorporated in the diaphragm device 2, and the rotation center pin 15a is engaged with the engagement hole 10b.

The diaphragm blade support plate 11 is provided with four engaging holes 11a in the same phase as the four insertion holes 10a, and the hole diameter of the engaging holes 11a is substantially equal to the diameter of the rotation center pin 16a. Four second diaphragm blades 16 are incorporated in the diaphragm device 2, and the rotation center pin 16a inserts the insertion hole 10a and engages with the engagement hole 11a of the diaphragm blade support plate 11. By incorporating the first diaphragm blade 15 and the second diaphragm blade 16 so as to overlap each other, the opening shape of the diaphragm device is formed at the inner edges of the plate portions 15c and 16c.

On the image pickup device side of the two types of diaphragm blades 15 and 16, the cam plate 12 is smoothly and rotatably held with respect to the diaphragm blade support cylinder 10, and the movement in the optical axis direction is restricted by the second presser washer 14. ing. The cam plate 12 has twelve first cam grooves 12a as shown in FIG. 2, and the drive pin 15b of the first throttle blade 15 and the drive pin 16b of the second throttle blade 16 are engaged with each groove. There is.

According to the above structure, when the cam plate 12 is rotated about the optical axis with respect to the diaphragm blade support cylinder 10, the drive pins 15b and 16b are guided along the first cam groove 12a, and the diaphragm blades 15 and 16 are the rotation center pins. It swings around 15a and 16a. Since the 12 diaphragm blades operate in the same manner, the diaphragm diameter formed by overlapping the diaphragm blades 15 and 16 can be changed.

Here, when the drive pins 15b and 16b are engaged at positions farthest from the optical axis of the first cam groove 12a, the aperture diameter is in the open state. Then, when the drive pins 15b and 16b are engaged at the positions closest to the optical axis of the first cam groove 12a, the first cam groove 12a is formed so that the aperture diameter is in the minimum aperture state.

The diaphragm device 2 of this embodiment is fixed to the inner diameter side of the fixed cylinder 17 of the lens device 1 as shown in FIG.

The aperture operation ring 18 engraved with an index indicating brightness on the outer circumference is engaged with the outer circumference of the fixed cylinder 17.

FIG. 3 shows an enlarged view of the aperture index notation portion of the lens device 1 of this embodiment.

The diaphragm operating ring 18 has an engaging portion that can be smoothly rotated, and a diaphragm interlocking pin 19 extending to the inner diameter side of the fixed cylinder 17 is screwed into the screw hole 18a. A long groove 17a through which the diaphragm interlocking pin 19 is inserted is provided in a part of the engaging portion of the fixed cylinder 17 with the diaphragm operating ring 18. The diaphragm interlocking pin 19 can rotate integrally with the diaphragm operation ring 18 without interfering with the fixed cylinder 17 within the angle range of the diaphragm operation rotation angle. The tip of the aperture interlocking pin 19 is engaged with the engagement groove of the connecting arm portion 12b extending from the cam plate 12 of the aperture device 2 toward the image pickup device.

On the subject side of the aperture operation ring 18, an index line ring 20 having an index line 20a engraved on the outer peripheral portion is fixed to the fixed cylinder 17.

Further, on the subject side of the index line ring 20, a mode operation ring 21 engraved with a mode selection display indicating the type of aperture opening shape is arranged on the outer periphery as shown in FIG. Here, the round-shaped marking in the mode selection display indicates that the aperture opening shape is substantially circular (shape imitating a circle; the first shape), and the elliptical marking indicates that the aperture opening shape is approximately elliptical (elliptical). It indicates that the shape imitates the shape; the second shape). The mode operation ring 21 is engaged with the outer circumference of the fixed cylinder 17 at the inner diameter portion, and the engaging portion can be smoothly rotated. A mode interlocking pin 22 extending to the inner diameter side of the fixed cylinder 17 is screwed into the screw hole 21a of the mode operation ring 21. A long groove 17b through which the mode interlocking pin 22 is inserted is provided in a part of the engaging portion of the fixed cylinder 17 with the mode operation ring 21. The mode interlocking pin 22 can rotate integrally with the mode operation ring 21 without interfering with the fixed cylinder 17 within the angle range of the mode operation rotation angle. The tip of the mode interlocking pin 22 is engaged with the engaging groove of the connecting arm portion 11b extending from the diaphragm blade support plate 11 of the diaphragm device 2 toward the subject.

The operation associated with the diaphragm operation and the opening shape switching operation of the diaphragm device 2 of the present embodiment configured as described above will be described below.

First, as shown in FIG. 3, when the index line 20a of the index line 20 and the round marking position of the mode operation ring 21 match, and the position of the index line 20a and the index "4" of the aperture match. Will be described. Each operating ring indicates that the aperture opening is substantially circular and is in an open state. FIG. 4A shows the aperture shape of the aperture device 2 at this time as seen from the image pickup device side, and FIG. 4B shows the state as seen from the subject side.

The rotation center pins 15a of the eight first diaphragm blades 15 and the rotation center pins 16a of the four second diaphragm blades 16 are arranged at equal intervals, and the drive pins 15b and 16b are all the lightest of the first cam groove 12a. It is located away from the axis. Therefore, as shown in FIG. 4, the opening shape is substantially circular.

Next, from the state of FIG. 4, it is assumed that the aperture operation ring 18 is rotated clockwise when viewed from the image pickup apparatus side, and the second index "5.6" and the index line 20a are matched. FIG. 5A shows the aperture shape of the aperture device 2 at this time as seen from the image pickup device side, and FIG. 5B shows the state as seen from the subject side.

The rotation center pin 15a and the rotation center pin 16b are arranged at equal angular intervals as in the state of FIG. On the other hand, since the cam plate 12 rotates clockwise when viewed from the image pickup device side in conjunction with the rotation of the aperture operation ring 18, the drive pins 15b and 16b are all guided in the direction approaching the optical axis along the first cam groove 12a. Will be done. Since all the first diaphragm blades 15 and the second diaphragm blades 16 rotate at equal angles around the rotation center pins 15a and 16a, respectively, the drive pins 15b and 16b are arranged on the same circumference having the same distance from the optical axis. To. Therefore, as shown in FIG. 5, the opening is smaller than the open state of FIG. 4 and has a substantially circular shape.

By the same operation, when the aperture operation ring 18 is further rotated in the same direction from the state of FIG. 5, the opening shape is substantially circular and the opening becomes smaller.

Next, a case where the mode operation ring 21 is rotated clockwise when viewed from the subject side from the state of FIG. 4 and the elliptical marking of the mode operation ring 21 and the index line 20a are matched will be described. FIG. 6A shows the aperture shape of the aperture device 2 at this time as seen from the image pickup device side, and FIG. 6B shows the state as seen from the subject side.

When the mode operation ring 21 is rotated, the interlocking diaphragm blade support plate 11 rotates in the same direction, and the position of the rotation center pin 16a of the second diaphragm blade 16 moves on the same circumference centered on the optical axis. .. Since the distance between the rotation center pin 16a and the drive pin 16b does not change regardless of the operation of the mode operation ring 21, the drive pin 16b at this time has the first cam so that the distance from the rotation center pin 16a is constant. It will move along the groove 12a in a direction approaching the optical axis. That is, the four second diaphragm blades 16 swing around the rotation center pin 16a, and the posture changes in the direction of narrowing the opening.

On the other hand, the other eight first diaphragm blades 15 in which the rotation center pin 15a does not engage with the engagement hole 11a of the diaphragm blade support plate 11 remain in the open opening state because their postures do not change at all.

As a result, as shown in FIG. 6, the opening shape of the diaphragm device 2 is narrower only in the horizontal direction with respect to the opening shape of FIG. 4, and becomes a vertically long substantially elliptical shape.

By the same action, when the mode operation ring 21 is switched in the direction of selecting the elliptical opening shape from the state of FIG. 5, or the aperture operation ring 18 is aligned with the index line 20a and the index "5.6" from the state of FIG. The opening shape of the diaphragm device 2 is as shown in FIG. That is, the opening is smaller and the opening shape is substantially elliptical.

As described above, according to the aperture device of the present embodiment, the photographer can continuously adjust the size of the aperture by using the same lens device, and the aperture shape can be switched between circular and elliptical. Can be done.

FIG. 8 is a side sectional view of a drawing device to which the present invention is applied in a second embodiment. Further, FIG. 9 is a partially decomposed perspective view showing the internal structure of the diaphragm device. In the figure, the same reference numerals as those in the first embodiment indicate the same members.

Hereinafter, the points where the configuration is different from that of the first embodiment will be described.

As shown in FIG. 8, the diaphragm device 3 is composed of a diaphragm blade support cylinder 30, a diaphragm blade support plate 31, a cam plate 12, two types of holding washers 13 and 14, and two types of diaphragm blades 15 and 16.

The diaphragm blade support cylinder 30 is provided with four engaging holes 30a located in the left-right direction and eight substantially arc-shaped second cam grooves 30b located in the vertical direction. The hole diameters of the four engaging holes 30a are substantially equal to the diameter of the rotation center pin 15a, and the groove widths of the eight second cam grooves 30b are substantially equal to the diameter of the rotation center pin 16a. The groove ends of the four engaging holes 30a and the eight second cam grooves 30b, which are closer to the optical axis, are arranged on the same circumference having the same distance from the optical axis, and are formed at equal angular intervals. ..

On the other hand, the diaphragm blade support plate 31 is provided with eight linear third cam grooves 31a in the same phase as the eight second cam grooves 30b. The groove widths of the eight third cam grooves 31a are all substantially equal to the diameter of the rotation center pin 16a, and the angle range is the same. Further, the groove end positions of the cam grooves 31a are equal in distance from the optical axis to the groove ends of the second cam grooves 30b having the same phase.

The first diaphragm blade 15 is incorporated so that the rotation center pin 15a engages with the engagement hole 30a, and the rotation center pin 16a of the second diaphragm blade 16 engages with both the second cam groove 30b and the third cam groove 31a. Incorporated to fit. By incorporating the first diaphragm blade 15 and the second diaphragm blade 16 so as to overlap each other, the opening shape of the diaphragm device is formed at the inner edges of the plate portions 15c and 16c.

The diaphragm device 3 of this embodiment is fixed to the inner diameter side of the fixed cylinder 17 of the lens device 4 as shown in FIG.

FIG. 10 shows an enlarged view of the aperture index notation portion of the lens device 4 of this embodiment.

On the subject side of the index line ring 20, a mode operation ring 41 engraved with a mode selection display indicating the type of aperture opening shape is arranged on the outer periphery as shown in FIG. The mode operation ring 41 is engaged with the outer circumference of the fixed cylinder 17 at the inner diameter portion, and the engaging portion can be smoothly rotated. A mode interlocking pin 22 extending to the inner diameter side of the fixed cylinder 17 is screwed into the screw hole 41a of the mode operation ring 41. A long groove 17b through which the mode interlocking pin 22 is inserted is provided in a part of the engaging portion of the fixed cylinder 17 with the mode operation ring 41, and the mode interlocking pin 22 is placed in the angle range of the mode operation rotation angle. It can rotate integrally with the mode operation ring 41 without interfering with the mode operation ring 41. The tip of the mode interlocking pin 22 is engaged with the engaging groove of the connecting arm 31b extending from the diaphragm blade support plate 31 of the diaphragm device 3 toward the subject.

The operation associated with the diaphragm operation and the opening shape switching operation of the diaphragm device 3 of the present embodiment configured as described above will be described below.

First, as shown in FIG. 10, when the index line 20a of the index line ring 20 and the round-shaped marking position of the mode operation ring 41 match, and the position of the index line 20a and the index “4” of the aperture match. Will be described. Each operating ring indicates that the aperture opening is substantially circular and is in an open state. FIG. 11A shows the aperture shape of the aperture device 3 at this time as viewed from the image pickup device side, and FIG. 11B shows the state as seen from the subject side.

The rotation center pins 15a of the four first diaphragm blades 15 and the rotation center pins 16a of the eight second diaphragm blades 16 are arranged at equal intervals and are arranged on the same circumference having the same distance from the optical axis. .. Further, the drive pins 15b and 16b are all located at positions farthest from the optical axis of the first cam groove 12a. Therefore, as shown in FIG. 11, the opening shape is substantially circular.

When the aperture operation ring 18 is rotated clockwise when viewed from the image pickup apparatus side from the state of FIG. 11, the size of the aperture can be reduced while keeping the aperture opening shape substantially circular as in the first embodiment.

Next, a case will be described in which the mode operation ring 41 is rotated clockwise when viewed from the subject side from the state of FIG. 11 so that the elliptical marking of the mode operation ring 41 and the index line 20a are matched. FIG. 12A shows the aperture shape of the aperture device 3 at this time as viewed from the image pickup device side, and FIG. 12B shows the state as viewed from the subject side.

When the mode operation ring 41 is rotated, the interlocking diaphragm blade support plate 31 rotates in the same direction. At this time, the four first diaphragm blades 15 in which the rotation center pin 15a does not engage with the diaphragm blade support plate 31 remain in the open opening state because their postures do not change at all.

On the other hand, as the diaphragm blade support plate 31 rotates, the rotation center pin 16a of the second diaphragm blade 16 that engages with the crossing position of the second cam groove 30b and the third cam groove 31a moves in a direction away from the optical axis. .. Since the position of the drive pin 16b has not changed, the eight second diaphragm blades 16 swing around the drive pin 16b, and the posture changes in the direction of narrowing the opening. As a result, the opening shape of the diaphragm device 3 becomes a non-circular shape. Since the postures of the eight second diaphragm blades 16 can be independently controlled by the eight second cam grooves 30b and the eight third cam grooves 31a, the opening of the diaphragm device is as shown in FIG. The shape can be a vertically long substantially elliptical shape.

As described above, according to the aperture device of the present embodiment, the photographer can continuously adjust the size of the aperture by using the same lens device, and the aperture shape can be switched between circular and elliptical. Can be done.

Further, in this embodiment, since the amount of change in the posture of the eight diaphragm blades can be set independently, the opening shape can be made closer to the elliptical shape.

Although the preferred embodiments of the present embodiment have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist thereof.

2,3 diaphragm device, 10,30 diaphragm blade support cylinder,
11,31 Aperture blade support plate, 10a, 11a, 30a Engagement hole,
12 cam plate, 12a 1st cam groove, 15, 16 diaphragm blades,
15a, 16a rotation center pin, 15b, 16b drive pin,
30b 2nd cam groove, 31a 3rd cam groove

Claims (7)

A plurality of diaphragm blades on which a rotation center pin and a drive pin are formed, a blade support portion that rotatably supports the diaphragm blades with the rotation center pin of each of the diaphragm blades as the rotation center, and the drive of each of the diaphragm blades. In a diaphragm device comprising a cam member having a first cam groove with which a pin engages.
The blade support portion is composed of at least two or more members, a first blade support member that cannot rotate about the optical axis and a second blade support member that can rotate about the optical axis. The rotation center pin is engaged with at least one of the engaging portions provided on the first blade supporting member and the second blade supporting member, respectively, and the second blade supporting portion is optical. A diaphragm device characterized in that the opening shape changes from the first shape to the second shape by rotating around an axis. The diaphragm device according to claim 1, wherein the opening shape changes from the first shape to the second shape when the second blade support portion rotates about an optical axis. The rotation center pin of some of the diaphragm blades engages with a first engagement hole provided in the first blade support member, and the rotation center pin of a plurality of other diaphragm blades supports the second blade. The drawing device according to claim 1 or 2, wherein the diaphragm device engages with a second engaging hole provided in the member. The rotation center pin of at least a part of the diaphragm blades is both a second cam groove provided on the first blade support member and a third cam groove provided on the second blade support member. The squeezing device according to claim 1 or 2, wherein the diaphragm device is engaged with. The diaphragm device according to any one of claims 1 to 4, wherein the innermost diameter of the diaphragm blade is larger than the maximum diameter of the opening of the first shape. A lens device having the diaphragm device according to claim 1. An imaging device including the lens device of claim 6 and a camera device connected to the lens device.