JP2021021798A - Diaphragm device - Google Patents

Abstract

To provide a diaphragm device which can switch the shape of an opening between a circle and an ellipse, and a lens device and an imaging device having the same.SOLUTION: The diaphragm device comprises: first diaphragm blades composed of at least two or more blades; a first cam member having a cam groove and moving in linkage with the first diaphragm blades via the cam groove; second diaphragm blades composed of at least two blades; a second cam member having a cam groove and moving in linkage with the second diaphragms via the cam groove; and an operation member that moves in linkage with the first and second cam members. At the reference position of the operation member, the first and second diaphragm blades work in such a way that when the operation member is displaced from the reference position to one direction when located at an open end, the first diaphragm blades are displaced in a close direction, and when the operation member is displaced from the reference position to a different direction from the one direction, the second diaphragm blades are displaced in a close direction.SELECTED DRAWING: Figure 1

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 angles on the same circumference, and the diaphragm opening formed by overlapping the inner edges of the diaphragm blades is changed by the rotation of the diaphragm blades around the rotation axis. There is a known squeezing device.

The aperture aperture 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, when the photographer uses one imaging device to switch between a circular aperture shape and an elliptical aperture shape according to a blurred image desired at the time of photographing, a structure for selecting a plurality of aperture aperture shapes as shown in Patent Document 1. Has been proposed.

Japanese Unexamined Patent Publication No. 04-269727

However, according to Patent Document 1 described above, the structure for switching the aperture shape constitutes a diaphragm opening having a plurality of aperture shapes as dedicated shapes, which hinders the miniaturization of the photographing apparatus. Further, during shooting of a moving image, if the opening shape is switched, light is not transmitted once at the switching portion, so that there is a problem that continuous switching cannot be performed.

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

In order to achieve the above object, the diaphragm mechanism according to the present invention is
The first diaphragm blade consisting of at least two blades,
A first cam member having a cam groove and interlocking with the first diaphragm blade through the cam groove,
A second diaphragm blade consisting of at least two blades,
A second cam member having a cam groove and interlocking with the second diaphragm blade through the cam groove,
The first cam member, the operating member interlocking with the second cam member, and
With
At the reference position of the operating member, when the first diaphragm blade and the second diaphragm blade are open ends, when the operating member is displaced in one direction from the reference position, the first diaphragm blade The diaphragm blades are displaced in the closing direction, and when the operating member is displaced from the reference position in a direction different from the one direction, the second diaphragm blade is displaced in the closing direction.

According to the present invention, it is possible to provide an aperture device capable of continuously switching between a circular and an elliptical opening shape according to the effect of bokeh that the photographer wants to obtain at the time of shooting simply by rotating the operation ring. ..

It is an overall view of the photographing apparatus in Example 1 of this invention. It is sectional drawing of FIG. 1 in Example 1 of this invention. It is an exploded perspective view inside the diaphragm mechanism in Example 1 of this invention. It is an enlarged view of the exploded perspective view inside the diaphragm mechanism in Example 1 of this invention. It is a left side figure which shows the closed end by the circular diaphragm blade in Example 1 of this invention. It is a front view which shows the closed end by the circular diaphragm blade in Example 1 of this invention. It is a right-right view which shows the closed end by the circular diaphragm blade in Example 1 of this invention. It is a left side figure which shows the intermediate diaphragm by the circular diaphragm blade in Example 1 of this invention. It is a front view which shows the intermediate diaphragm by the circular diaphragm blade in Example 1 of this invention. It is a right-right view which shows the intermediate diaphragm by the circular diaphragm blade in Example 1 of this invention. It is a left side figure which shows the open end in Example 1 of this invention. It is a front view which shows the open end in Example 1 of this invention. It is a right side figure which shows the open end in Example 1 of this invention. It is a left side figure which shows the intermediate diaphragm by the diaphragm blade for ellipse in Example 1 of this invention. It is a front view which shows the intermediate diaphragm by the diaphragm blade for ellipse in Example 1 of this invention. It is a right-right view which shows the intermediate diaphragm by the diaphragm blade for ellipse in Example 1 of this invention. It is a left side figure which shows the closed end by the elliptical diaphragm blade in Example 1 of this invention. It is a front view which shows the closed end by the diaphragm blade for ellipse in Example 1 of this invention. It is a right-right view which shows the closed end by the diaphragm blade for ellipse in Example 1 of this invention.

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

Hereinafter, the diaphragm device 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 7.

FIG. 1 shows an overall view of the photographing apparatus in this embodiment.

In the description of this embodiment, it is assumed that the circular diaphragm is formed by 12 circular diaphragm blades 11 and the elliptical diaphragm is formed by 12 elliptical diaphragm blades 12.

The aperture device 1 is an aperture drive unit that sets the aperture diameter of a lens group such as a focus and zoom (not shown) and a relay unit, and continuously changes the aperture opening shape. The diaphragm device 1 is configured with an operation ring 2 which can be manually operated and has a gear 1a whose outer shape is connected to a motor or a rotation operation member (not shown). The operation ring 2 slides and rotates the outer shape of the fixed cylinder 3 that is connected to the lens group (not shown) in the front-rear direction, and is connected to the fixed cylinder 3 by the fixing screw (not shown) in the optical axis direction. Movement is restricted.

A diaphragm operation ring display unit 2a indicating brightness is displayed on the operation ring 2. On the operation ring display unit 2a, a display 2b from open to closed in a circular diaphragm and a display 2c from open to close in an elliptical diaphragm are displayed.

The photographer may rotate the operation ring 2 and align the numerical value of the operation ring display unit 2a with the index line 3a engraved on the fixed cylinder 3 by printing or engraving so that the desired brightness is obtained.

FIG. 2 shows a cross-sectional view of FIG.

A circular connecting shaft 5 and an elliptical connecting shaft 6 are fixed to the operation ring 2. The tip of the circular connecting shaft 5 fits into the connecting hole 7a integrally provided with the circular cam member 7 forming the circular diaphragm. The tip of the elliptical connecting shaft 6 fits into the connecting hole 8a integrally provided with the elliptical cam member 8 forming the elliptical throttle.

The circular cam member 7 holds the inner diameter of the diaphragm blade accommodating portion 9 in a slidable state, and when the operation ring 2 is rotated, the rotational force is transmitted to the circular cam member 7 by the circular connecting shaft 5 to rotate. .. The circular cam member 7 is restricted from moving in the optical axis direction by a C ring 10 or the like.

Similarly, the elliptical cam member 8 holds the inner diameter of the throttle blade accommodating portion 9 in a slidable state, and when the operation ring 2 is rotated, the rotational force is transmitted to the elliptical cam member 8 by the connecting shaft 6 for the ellipse. Rotate. The elliptical cam member 8 is restricted from moving in the optical axis direction by a C ring 10 or the like.

The diaphragm blade accommodating portion 9 is fixed to the fixing cylinder 3 by a diaphragm blade accommodating portion fixing member 14 in a state where rotation around the central axis is restricted by a rotation pin or the like (not shown). A screw is formed on the outer peripheral portion of the diaphragm blade accommodating portion fixing member 14, and is fixed to the inner diameter screw portion of the fixing cylinder 3 by screw connection.

From FIG. 3B, the diaphragm blade accommodating portion 9 is provided with 12 circular hole portions 9a that fit with the pin 11a that is the rotation axis of the circular diaphragm blade 11 that forms the circular diaphragm. The circular hole portions 9a are provided on the same circumference, and their phase intervals are evenly divided.

Further, the diaphragm blade accommodating portion 9 is provided with 12 elliptical hole portions 9b that are fitted with pins 12a serving as a rotation axis of the elliptical diaphragm blade 12 forming the elliptical diaphragm, and the elliptical hole portions 9b are in the same circle. It is provided on the circumference, and the phase spacing of each is evenly divided.

From FIG. 3B, the 12 circular diaphragm blades 11 are formed with circular drive pins 11b that engage with the circular cam groove 7b of the circular cam member 7. Similarly, the 12 elliptical diaphragm blades 12 are formed with elliptical drive pins 12b that engage with the elliptical cam groove 8b of the elliptical cam member 8.

From FIG. 6A, the circular cam groove 7b is provided with 12 cam grooves having the same shape. When the operation ring 2 is rotated in the A direction, the plurality of circular diaphragm blades 11 of the circular cam groove 7b are displaced in a direction approaching the center O of the optical axis, and become a closed end at the end of the cam groove. The changes in the displacement state at this time are shown in the order of FIGS. 6, 5, and 4. ..

Further, the circular cam groove 7b is circular at a position having a diameter of α mm shown in FIG. 6A by rotating the operation ring 2 in the B direction to displace the plurality of circular diaphragm blades 11 in a direction away from the center O of the optical axis. When the drive pin 11b is positioned, it becomes an open end. The changes in the displacement state at this time are shown in the order of FIGS. 4, 5, and 6.

From FIG. 6C, the elliptical cam groove 8b is composed of two cam grooves of six types for each type, and a total of twelve cam grooves are provided. When the operation ring 2 is rotated in the B direction, the plurality of elliptical diaphragm blades 12 of the elliptical cam groove 8b are displaced in a direction approaching the center O of the optical axis, and become a closed end at the end of the cam groove. The changes in the displacement state at this time are shown in the order of FIGS. 6, 7, and 8.

Further, when the operation ring 2 is rotated in the A direction, the plurality of elliptical diaphragm blades 12 are displaced in the direction away from the center O of the optical axis, and the elliptical cam groove 8b is elliptical at a position having a diameter of α mm shown in FIG. 6 (c). When the drive pin 12b is positioned, it becomes an open end. The changes in the displacement state at this time are shown in the order of FIGS. 8, 7, and 6.

From this, in the aperture device 1, when the operation ring 2 is rotated in one direction with reference to the time when the "OPEN" displayed on the operation ring display unit 2a is aligned with the index line 3a, the circular aperture is closed toward the closed end. Displace to. Further, in the aperture device 1, when the operation ring 2 is rotated in the opposite direction with reference to the time when the “OPEN” displayed on the operation ring display unit 2a is aligned with the index line 3a, the aperture for the ellipse is displaced in the closing direction. ..

In this embodiment, a circular diaphragm and an elliptical diaphragm have been described, but the diaphragm may not be an elliptical diaphragm. For example, the first cam member and the first diaphragm blade are composed of six cam grooves and blades, and the second cam member and the second diaphragm blade are composed of eight cam grooves and blades. You may. As a result, when the operation ring 2 is rotated in one direction, a substantially circular opening shape (mimicking a circle) is formed by a hexagon, and when the operation ring 2 is rotated in the opposite direction, a substantially circular (circular) shape is formed by an octagon. An opening shape (which imitates) is formed.

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

2 Operation ring, 3 Fixed cylinder, 4 Operation ring retainer, 5 Connecting shaft for circle,
6 Connecting shaft for ellipse, 7 Circular cam member, 7b Circular cam groove,
8 elliptical cam member, 8b elliptical cam groove, 9 diaphragm blade storage,
11 Circular diaphragm blades, 12 Elliptical diaphragm blades

Claims (4)

It is composed of at least two diaphragm blades, a first diaphragm blade having at least two diaphragm blades, and a first cam member having a cam groove and interlocking with the first diaphragm blade through the cam groove. A second diaphragm blade, a second cam member having a cam groove and interlocking with the second diaphragm blade via the cam groove, the first cam member, and interlocking with the second cam member. When the first diaphragm blade and the second diaphragm blade are open ends at the reference position of the operating member, the operating member is moved in one direction from the reference position. When displaced to, the first diaphragm blade is displaced in the closing direction, and when the operating member is displaced from the reference position in a direction different from the one direction, the second diaphragm blade is displaced in the closing direction. Aperture mechanism featuring. When the operating member is displaced in one direction from the reference position and the first diaphragm blade is displaced in the closing direction, the second diaphragm blade is located at the open end, and the one direction is from the reference position. The diaphragm mechanism according to claim 1, wherein the first diaphragm blade is located at an open end when the second diaphragm blade is displaced in a different direction and the second diaphragm blade is displaced in the closed direction. The opening of the first shape is formed while the operating member is displaced in one direction from the reference position, and the opening of the second shape is formed while the operating member is displaced in a direction different from the one direction from the reference position. The throttle mechanism according to claim 1 or 2. The invention according to any one of claims 1 to 3, wherein the first diaphragm blade and the second diaphragm blade are substantially formed so as to have the same structure as each other. Aperture mechanism.