JP2018205477A - Blade driving device and imaging apparatus - Google Patents

Abstract

To suppress change in a position of a diaphragm relative to an optical axis caused by overlapping of diaphragm blades with each other.SOLUTION: A blade driving device includes: a plurality of diaphragm blades for forming a diaphragm opening by going into and out of a light passage opening; a drive ring for driving the diaphragm blades; and a base member that rotatably supports the drive ring and has the light passage opening. The blade driving device includes a suppressing member for suppressing displacement in a light passage direction of a blade tip when the blade tip of the plurality of diaphragm blades enters into the light passage opening to form the diaphragm opening.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a blade driving device mounted on an optical device such as an imaging device or an interchangeable lens.

  The shape of the aperture opening as the light passage aperture formed in the blade driving device (aperture device) is preferably as close to a circle as possible, and in order to form a stop aperture close to a circle, a large number of three or more aperture blades ( In many cases, a light adjustment blade is used.

  Patent Document 1 discloses an iris diaphragm device that forms a polygonal diaphragm opening close to a circle by rotating a large number of diaphragm blades by a drive ring that can rotate around a fixed opening formed in a base member. It is disclosed.

JP 2017-58443 A

  However, in the iris diaphragm device as disclosed in Patent Document 1, the leading edge of the diaphragm blade is knitted in the optical axis direction due to the overlap of the diaphragm blades, and the aperture position changes the aperture area along the optical axis direction. There is a problem that changes.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a blade driving device having a stable diaphragm position and an optical apparatus having the same, so as to suppress knitting of the diaphragm blades.

In view of the above, the blade driving device and the imaging device of the present invention are
A plurality of aperture blades that enter and exit the light passage aperture to form an aperture aperture;
A drive ring for driving the diaphragm blades;
A base member rotatably supporting the drive ring and having a light passage opening;
When the blade tips of the plurality of diaphragm blades enter the light passage opening to form the diaphragm opening,
It has a suppressing member that suppresses displacement of the blade tip in the light passing direction.

  According to the present invention, it is possible to suppress a change in the aperture position in the optical axis direction that occurs due to overlapping of aperture blades.

FIG. 3 is an exploded perspective view of the blade driving device according to the first embodiment. The front view which shows the change of the aperture opening of Embodiment 1 (without a cover). 1 is a perspective view and a schematic cross-sectional view of a blade driving device according to Embodiment 1. FIG. The aperture blade and the holding member of Embodiment 1. The blade knitting up state when there is no restraining member. An optical device equipped with a blade drive when there is no holding member. The optical apparatus carrying the blade | wing drive device of this invention. FIG. 3 is an enlarged cross-sectional view of the blade driving device according to the first embodiment. The expanded sectional view of the other aspect of the blade | wing drive device of Embodiment 1. FIG. FIG. 4 is an exploded perspective view of a blade driving device according to a second embodiment. FIG. 6 is a perspective view of a blade driving device according to a second embodiment. The aperture blade and the holding member of Embodiment 2. Sectional drawing of the optical member of Embodiment 2. FIG. Sectional drawing of the fixed opening of a prior art. FIG. 6 is an exploded perspective view of a blade driving device according to a third embodiment. FIG. 6 is a perspective view of a blade driving device according to a third embodiment. FIG. 6 is an aperture blade and a holding member according to Embodiment 3. FIG. The drive ring of Embodiment 3. FIG. 6 is an exploded perspective view of a blade driving device according to a fourth embodiment. FIG. 6 is a perspective view of a blade driving device according to a fourth embodiment.

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

<Embodiment 1>
FIG. 1 shows an exploded perspective view of a diaphragm device as a blade driving device which is an example of the blade driving device according to the first embodiment of the present invention. 1A and 1B are exploded perspective views as seen from different directions.

  In FIG. 1, the diaphragm device is driven around the optical axis center 100 of the blade driving device. The drive unit 101 serves as a drive source that drives the blade drive device. The base member 102 is an opening forming member having an opening 102a (light passage opening) formed at the center. In this embodiment, for example, the base member 102 is formed by resin molding and has a plurality of engagement pins 102d. The drive unit 101 is attached to the end of the base member 102. Examples of the drive unit 101 include a stepping motor and a galvanometer. A pinion gear 103 is attached to the rotation shaft of the drive unit 101.

  In the present embodiment, for example, the rotating member 104 is a circular sheet-like member formed by resin molding, and has an opening formed with a circular opening serving as a path through which light passes at the center. It is a member (drive ring).

  The rotating member 104 is provided with a plurality of standing drive pins 104c, a driven portion 104e provided at an outer peripheral end to which the pinion gear 103 is connected, and a portion protruding at the outer peripheral end. And a light shielding portion 104f.

  Here, the rotating member 104 is formed by, for example, pressing a resin film (PET sheet material or the like). When the rotating member 104 is made of a resin film, the rotating member 104 can be made thin and light. Further, when the rotating member 104 is made of a resin film, the portion that guides the operation of the rotating member 104 does not require strength compared to the case where the rotating member is formed by resin molding. For example, the rotating member 104 can be guided by a thin guide pin that guides the diaphragm blades. When press working can be performed, the shape accuracy can be formed with higher accuracy than the shape accuracy of resin molding, so that the drawing accuracy can be high. Of course, the rotating member 104 is not necessarily formed by a thin sheet-like member, and may be formed by resin molding.

  The rotating member 104 has a gear portion that is a driven portion 104e. The driven portion 104e meshes with the pinion gear 103. The rotational force generated in the drive unit 101 is transmitted from the pinion gear 103 to the driven unit 104e, whereby the rotating member 104 rotates. In the present embodiment, the rotational force of the drive unit 101 is transmitted from the pinion gear 103 to the rotating member 104. For example, a drive lever may be used instead of the pinion gear. When a drive lever is used, the driven portion 104e of the rotating member 104 may be a cam groove or a driven pin.

  Further, when the light shielding portion 104f enters and exits through a slit of a photo interrupter (not shown), it functions as a sensor that detects the position of the rotating member 104. Used to detect the initial position of the blade drive device.

  In the present embodiment, for example, in the present embodiment, a plurality (nine) of diaphragm blades 105 are annularly arranged so as to surround an opening through which light passes. Each aperture blade 105 is formed with an engagement hole 105c and a cam groove 105d, which are driven parts. Such a diaphragm blade 105 may be formed by, for example, pressing a PET sheet material or the like, or may be formed by resin molding or the like.

  In the present embodiment, nine diaphragm blades are used. However, the number of diaphragm blades may be any number as long as it is two or more. In this embodiment, the diaphragm blade 105 is described as an example, but other blade blades such as other shutter blades or blades having an optical filter may be used. The maximum opening of the portion through which light passes may be defined by the opening 106 a of the base member 102 or the cover member 106, or may be defined by the ends of the plurality of aperture blades 105.

  This cover member 106 accommodates the above-described plurality of diaphragm blades 105 and the rotation member 104 for driving these blades with the base member 102, and forms a blade chamber in which the blades travel with the rotation member. To do. That is, the plurality of diaphragm blades 105 travel (drive) in the blade chamber (space) formed by the base member 102 and the cover member 106 as the rotating member 104 rotates. The cover member 106 is formed with an opening 106 a that communicates with the opening of the base member 102, and is an opening forming member, like the base member 102. The cover member 106 may be formed by resin molding or the like, or may be created by pressing a PET sheet material or the like.

  The engagement hole 105 c of the diaphragm blade 105 engages with the drive pin 104 c of the rotating member 104. The pinion gear 103 rotates, a force is transmitted to the driven part 104e of the rotating member 104, and the rotating member 104 rotates. Then, a driving force is applied from the driving pin 104c of the rotating member 104 to the engagement hole 105c of the diaphragm blade 105, and the diaphragm blade 105 is driven. At this time, the cam groove 105 d of the diaphragm blade 105 is engaged with the engaging portion 102 d of the base member 102.

  Therefore, the diaphragm blade 105 enters and exits the opening of the base member 102 through the cam groove 105d. Accordingly, the diaphragm shape of the plurality of diaphragm blades 105 is adjusted in the opening 102a of the base member 102, and the amount of light passing through can be adjusted. FIG. 2 shows a state where the cover member 106 shown in FIG. 1 is removed. FIG. 2A shows a state in which the aperture is open, and FIG. 2B shows a state in which the aperture is small.

  The restraining member 107 is made of, for example, an optical member (such as a glass material or a resin film material) through which light passes. In the first embodiment, the restraining member 107 is described as a flat sheet-like member, but the restraining member 107 may be a lens whose surface is formed in a concave shape or a convex shape. The restraining member 107 can restrain the knitting of the diaphragm blade 105 by sliding contact with the diaphragm blade 105.

  The plurality of diaphragm blades 105 are annularly incorporated so that the blade tip portions are knitted in the direction of the base member 102. The holding member 107 is arranged on the knitting direction side of the diaphragm blades 105 so as to be adjacent to the plurality of diaphragm blades 105. Therefore, the aperture opening position formed by the plurality of aperture blades 105 can be stabilized at a position adjacent to the restraining member 107.

  In FIG. 1, the diaphragm blade 105 is assembled with the knitting direction on the rotating member 104 side, and the restraining member 107 is disposed on the rotating member 104 side. However, the diaphragm blade 105 is assembled with the knitting direction of the diaphragm blade 105 on the cover member 106 side. The restraining member 107 may be disposed on the cover member 106 side. In any case, the amount of knitting of the diaphragm blade 105 can be suppressed by disposing the restraining member 107 in the knitting up direction of the diaphragm blade 105 and suppressing the tip of the knitted diaphragm blade 105. That is, it is possible to suppress the displacement of the front end portion of the diaphragm blade 105 in the light passing direction.

  Although FIG. 1 shows an example in which the holding member 107 is fixed to the engaging pin 102d provided on the base member 102, the holding member 107 may be fixedly attached to the cover member 106. Further, the holding member 107 may be fixed to the drive pin 104 c provided on the rotating member 104 and rotated together with the rotating member 104. In this case, a cam groove is provided in a portion of the holding member 107 corresponding to the engaging portion 102d so as to avoid interference with the engaging portion 102d. When configured to rotate together with the rotating member 104, the sliding distance between the aperture blade 105 and the holding member 107 can be shortened.

  In FIG. 3, the perspective view of Embodiment 1 and the schematic cross section in the plane containing an optical axis are shown. The plurality of aperture blades 105 are knitted in the direction of the base member 102 and are restrained by the restraining member 107. Further, as shown in the cross-sectional view, the holding member 107 is engaged with the engaging portion 102d of the base member 102, and the outer peripheral side portion thereof is a portion inside the drive pin 104c on the rotating member 104. It is sandwiched between the diaphragm blades 105. Note that the inner peripheral end of the rotating member 104 is positioned by the engaging portion 102d as shown in this figure. FIG. 4 is a diagram illustrating only the states of the plurality of diaphragm blades 105 and the holding member 107.

  FIG. 5 shows a state in which the diaphragm blades are knitted without the restraining member 107. In this case, the amount of knitting at the tip of the aperture blade increases as the aperture state changes to the small aperture state. In addition, the problem is that the aperture position formed by the plurality of aperture blades 105 changes as the aperture state becomes smaller, whereas in the first embodiment, the restraining member 107 causes the aperture blades 105 to be knitted. In order to suppress it, the aperture opening position can be stabilized. In this figure, an engagement pin 105f is provided in place of the engagement hole 105c for the aperture blade, and a drive pin 105g is provided in place of the cam groove 105d, whereby the base member 102 and the rotation member 104 are respectively provided. The mode which drives a diaphragm blade | wing by engaging with the engagement hole provided in these is shown.

  FIG. 6 shows a cross-sectional view of an optical apparatus provided with a blade driving device when the holding member 107 is not provided. In this case, it is necessary to secure a sufficient space L so that the diaphragm blades and the lens Ls do not contact each other in consideration of the knitting amount of the diaphragm blades. The height of the tip of the aperture blade knitted in an annular shape varies depending on various factors such as the size, thickness, material, minimum aperture diameter, etc. of the blade, so that it was very difficult to calculate. Therefore, it is necessary to secure a sufficient distance in the space L, and in some cases, the waste is large.

  FIG. 7 is a cross-sectional view of an optical apparatus including the blade driving device according to the first embodiment. It can be seen that since the restraining member 107 restrains the knitting of the diaphragm blade 105, the diaphragm opening position can be stabilized in the optical axis direction. Further, since the braiding of the diaphragm blade 105 is suppressed by the restraining member 107, the space L ′ can be set ignoring the braiding of the diaphragm blade 105. Therefore, the space L ′ can be significantly reduced as compared with the case where the suppressing member 107 is not provided. Since the space L ′ can be reduced, the degree of freedom in optical design can be increased, and the performance of the optical apparatus can be improved. For example, it can contribute to increasing the zoom magnification in an optical apparatus.

  Further, the blade driving device of the first embodiment is also effective for high-speed driving. In the conventional blade driving device, when the diaphragm blade is driven at a high speed to a predetermined diaphragm area, the tip of the diaphragm blade that has entered the fixed opening bounces (the direction of the blade tip into the fixed opening and the fixed opening outside the fixed opening). Therefore, it took a certain time for the diaphragm blades to stop and the diaphragm area to stabilize. In the blade driving device of the first embodiment, the leading edge of the diaphragm blade 105 is adjacent to the restraining member 107 in the fixed opening, so that the bounding of the leading edge of the diaphragm blade that occurs when driven at high speed is suppressed. be able to. This is because the restraining member 107 can come into contact with the diaphragm blade 105 to restrict the movement of the diaphragm blade.

  Since the diaphragm blades stop without bouncing after high-speed driving, in the imaging device equipped with the blade driving device of Embodiment 1, it is possible to shorten the time from when the blade driving device is driven until shooting. In particular, in a large-diameter blade driving device, the diaphragm blade is large, and the amount of bounce at the tip of the diaphragm blade when driven at high speed is large.

  In addition, when the holding member 107 is not provided, a voltage for stopping the driving unit for a certain time is applied to stop the diaphragm blades. In the first embodiment, the time of the voltage used for the stop can be shortened or eliminated, so that the power consumption is also effective. In the case where the restraining member 107 is not provided, a method of restraining the bounce by reducing the drive speed has been used in order to restrain the bounce at the tip of the aperture blade. The first embodiment is effective for high-speed driving because the leading edge of the diaphragm blade does not bounce even when the diaphragm blade is driven at the highest speed.

  Furthermore, the first embodiment is also effective for driving sound. In the blade driving device, a plurality of diaphragm blades rub against each other and drive sound is generated during high-speed operation. In the first embodiment, the restraining member 107 can prevent the driving sound generated from the diaphragm blade 105 from leaking out of the blade driving device. Therefore, the blade driving device of Embodiment 1 is effective for noise reduction.

  In addition, the blade driving device of the present embodiment is effective for noise reduction even during low-speed operation. As shown in FIG. 1, the plurality of diaphragm blades 105 are arranged in an annular shape so that the front and back surfaces of adjacent diaphragm blades overlap each other, and the leading end side of the diaphragm blades is knitted in one direction. FIG. 8 shows an example in which the knitting direction at the tip of the diaphragm blade is the direction opposite to the rotating member 104 (direction A in FIG. 8). In this figure, unlike the cross-sectional view of FIG. 3, a mode in which the holding member 107 is provided so as to cover the rotating member 104 beyond the drive pin 104 c of the rotating member 104 is shown. A cam groove is provided in a portion 107 corresponding to the drive pin 104c.

  Since the diaphragm blade 105 is made of an elastic material, when the tip of the diaphragm blade 105 is knitted in the A direction and the tip A of the diaphragm blade 105 is brought into contact with the restraining member 107, the tip of the diaphragm blade 105 On the side of the engagement hole 105c opposite to the side, a force is generated in the B direction. That is, the rotating member 104 is biased toward the base member 102 side.

  Here, the effect of pressing and urging the rotating member 104 toward the base member 102 will be described. In FIG. 8, the rotating member 104 and the diaphragm blade 105 rotate in a driving space h formed by the base member 102 and the cover member 106. When the rotating member 104 can move to the base member 102 side or the cover member 106 side in the driving space h, the gear of the driven portion 104e in the rotating member 104 is the pinion gear. When meshing with 103, the rotating member 104 rotates while vibrating in the driving space h due to the accuracy of the gear and the inclination of the gear. As a result, a phenomenon (fluttering) in which the rotating member 104 approaches or moves away from the base member 102 or the cover member 106 may cause noise.

  In FIG. 8 in the first embodiment, as described above, when the rotation member 104 is rotated and the leading end side of the aperture blade 105 enters the aperture opening (the aperture opening diameter is reduced), the rotation member 104 is moved. Since the biasing member 104 is biased toward the base member 102 side, the rotation member 104 can be prevented from moving toward the base member 102 side within the driving space h or moving toward the cover member 106 side. That is, it is possible to prevent noise caused by the swing of the rotating member 104. In the first embodiment, the rotating member 104 can be urged toward the base member 102 by the diaphragm blade 105, and the noise can be reduced.

  Here, the holding member 107 will be described in more detail. The suppression member 107 is formed of an optical member through which light passes. For example, a base material is formed with a transparent resin film, and an antireflection coating is applied to the surface. By applying an antireflection coating to the suppression member 107, it is possible to reduce the loss of the amount of light that passes through the aperture opening formed by the aperture blade 105.

  The antireflection coating may be a single layer film made of magnesium fluoride or the like, or may be a multilayer film. Further, the holding member 107 may be provided with functions such as an ND filter and an IR cut filter. The suppressing member 107 not only suppresses the knitting of the diaphragm blade 105 but also can add optical performance according to the application. According to this configuration, it is possible to improve the optical performance without increasing a new space.

  Furthermore, an antistatic agent may be applied to the surface of the suppressing member 107 as a surface treatment. By applying the antistatic agent, charging due to friction with the diaphragm blade 105 can be reduced, and the operation load can be reduced.

  Further, a transparent sliding agent (sliding coat) may be applied to the surface of the holding member 107 as a surface treatment. By applying the sliding agent, friction with the diaphragm blade 105 can be reduced, and the operation load can be reduced and the durability can be improved. Further, it is possible to suppress scratches due to contact between the holding member 107 and the diaphragm blade 105.

  Further, the operation load on the holding member 107 can be reduced by the shape of the diaphragm blade 105. FIG. 9 shows an example in which a contact portion 105e for the holding member 107 is provided in a part of the diaphragm blade 105. A contact portion 105 e of the diaphragm blade 105 contacts the holding member 107. The abutting portion 105 e is a chamfered inclined surface provided on the end face on the distal end side in the rotational direction of the diaphragm blade 105, the contact position between the diaphragm blade 105 and the holding member 107 and the distal end in the rotational direction overlapping with the other diaphragm blade 105. It is provided on the side end face. In the present embodiment, the diaphragm blade 105 is provided from the position where the edge of the diaphragm opening is formed to the blade tip.

  By providing such a contact portion 105e, it is possible to reduce rubbing of the end face of the diaphragm blade 105 against the restraining member 107, so that it is possible to prevent the restraining member 107 from being scratched and to improve durability.

  In the first embodiment, an example in which the diaphragm blade 105 has a cam groove has been described. However, the diaphragm blade 105 is provided with a drive pin, and the rotation member (drive ring) or the base member is provided with a cam groove so that the diaphragm blade is fixedly opened. It is good also as a structure which goes in and out. This is effective in any blade driving device in which a plurality of diaphragm blades are incorporated in a ring shape and the diaphragm blades are knitted.

<Embodiment 2>
In FIG. 10, the disassembled perspective view of the aperture_diaphragm | restriction apparatus as a blade | wing drive device which is Embodiment 2 of this invention is shown. 10A and 10B are exploded perspective views as seen from different directions. The diaphragm device is driven around the optical axis center 200 of the blade driving device. The basic configuration is the same as that of the first embodiment.

  FIG. 11 is a perspective view of the second embodiment. The plurality of diaphragm blades 205 are knitted in the direction of the base member 202 and are restrained by the restraining member 207. FIG. 12 is a diagram showing the state of the plurality of diaphragm blades 205 and the holding member 207 in an extracted manner. Since the suppressing member 207 suppresses the knitting of the aperture blade 205, the aperture opening position can be stabilized with respect to the optical axis direction.

  The restraining member 207 has a light shielding part 207k and a restraining part 207g. The light shielding part 207k is a vapor deposition film that shields light. The light shielding portion 207k preferably has an antireflection function in addition to the light shielding property. The light shielding part 207k is deposited in a ring shape, and a restraining part 207g, which is an optical part through which light passes, is formed inside the light shielding part 207k. The fixed opening 207a is formed by making the boundary between the light shielding part 207k and the restraining part 207g circular.

  FIG. 13 shows a cross-sectional view of the holding member 207. FIG. 14 is a cross-sectional view of the fixed opening 202a when the holding member 207 is not provided. In this case, since the end surface 202a of the fixed opening is formed by resin molding or the like, a certain thickness is required. In the second embodiment, since the fixed opening 207a is formed of a vapor deposition film, the end surface of the fixed opening 207a can be thinned to the film thickness level as shown in FIG. Therefore, reflection of light at the end face of the fixed opening can be suppressed, and ghosts that cause problems with lenses and the like can be reduced.

<Embodiment 3>
In FIG. 15, the disassembled perspective view of the aperture_diaphragm | restriction apparatus as a blade drive device which is an example of the blade drive device which is Embodiment 3 of this invention is shown. 15A and 15B are exploded perspective views as seen from different directions. The diaphragm device is driven around the optical axis center 300 of the blade driving device. Although the basic configuration is the same as in the first and second embodiments, in the third embodiment, the drive ring 304 is configured to have the function of the holding member in the first and second embodiments. That is, the holding member is provided integrally with the drive ring 304.

  FIG. 16 is a perspective view of the third embodiment. FIG. 17 is a diagram showing the state of the plurality of diaphragm blades 305 and the drive ring 304 in an extracted manner. The drive ring 304 of the third embodiment has a restraining part 304g and a light shielding part 304k. Details and effects of the suppression portion 304g and the light shielding portion 304k are the same as those in the second embodiment.

  The plurality of diaphragm blades 305 are knitted in the direction of the base member 302 and are restrained by the restraining portion 304g of the drive ring 304. Since the restraining part 304g of the drive ring 304 restrains the knitting of the diaphragm blade 305, the aperture opening position can be stabilized with respect to the optical axis direction.

  As described above, the third embodiment can suppress the knitting of the diaphragm blade 305 without increasing the number of components by adding a suppression function to the drive ring 304.

  FIG. 18 shows an applied shape of the drive ring 304. In the first embodiment, the light shielding unit 104f and a photo interrupter (not shown) are used for detecting the position of the drive ring. In the drive ring of FIG. 18, a plurality of slit shapes 304s are provided in the light shielding portion 304k, and a photo interrupter is provided at a corresponding position.

  When the drive ring 304 is rotated, the output of the photo interrupter or the like detects the number of times the slit is present, so that the rotation amount and position of the drive ring 304 can be detected. In addition, since the slit shape 304s is formed by vapor deposition or the like, it is possible to form a narrow slit as compared with the case where the slit is formed by the outer shape of the drive ring. Therefore, high position accuracy can be realized.

  In the first embodiment, the initial position is detected by the photo interrupter, and the aperture position is detected by the number of steps of the stepping motor. However, by providing the drive ring 304 with the slit shape 304s, not only the initial position but also the aperture position is known. It is possible. For this reason, in the present embodiment, it is possible to control the exact aperture position even when a driving unit having a unstable driving distance, such as a piezo element, is used. As a result, the conditions of the drive unit that can be mounted are relaxed, so that it is easy to mount a small drive unit, and the entire aperture device can be made smaller and thinner.

<Embodiment 4>
In FIG. 19, the disassembled perspective view of the aperture_diaphragm | restriction apparatus as a blade drive device which is Embodiment 4 of this invention is shown. The diaphragm device is driven around the optical axis center 400 of the blade driving device. FIG. 20 is a perspective view of the fourth embodiment. The fourth embodiment is an example in which the cover member 406 has the function of the holding member described in the first to third embodiments. The details and effects of the suppression member are the same as those of the first to third embodiments, and include a suppression part 406g and a light shielding part 406k. The plurality of aperture blades 405 are knitted in the direction of the cover member 406 and are suppressed by the cover member 406. The cover member 406 that accommodates the diaphragm blade 405 so as to be movable between the base member 402 suppresses the knitting of the diaphragm blade 405, so that the position of the diaphragm opening can be stabilized with respect to the optical axis direction.

  As described above, the fourth embodiment can suppress the knitting of the diaphragm blades 405 without increasing the number of components by adding a suppressing function to the cover member 406.

  In each embodiment described above, the suppressing member (suppressing part) is provided over all the portions in the fixed opening, and the suppressing member is not provided with an opening. When the suppression member is configured to have an opening, the ghost as described with reference to FIG. 14 is likely to occur due to reflection at the end face of the opening. However, according to this configuration, the suppression member is provided in the fixed opening, particularly in the aperture opening. Since no opening is formed, end face reflection does not occur, and generation of ghost can be reduced.

  Further, in each embodiment, the mode in which the diaphragm blades are knitted by incorporating them as described above is described as an example. However, the configuration of the diaphragm blades is not necessarily knitted, and a large number of diaphragm blades are used. A stacked configuration may be used. In a configuration in which a large number of diaphragm blades are stacked, the tip of the diaphragm blade may protrude in the optical axis direction within the fixed opening due to the inclination during driving of the diaphragm blade. If there is a restraining member, the position of the front end of the diaphragm blade in the optical axis direction can be regulated, so that even a configuration in which a large number of diaphragm blades are stacked is effective for downsizing.

101 Diaphragm drive unit 102 Base member (base plate)
103 Pinion gear 104 Drive ring 105 Diaphragm blade 106 Cover 107 Holding member

Claims (7)

A plurality of aperture blades that enter and exit the light passage aperture to form an aperture aperture;
A drive ring for driving the diaphragm blades;
A base member rotatably supporting the drive ring and having a light passage opening;
When the blade tips of the plurality of diaphragm blades enter the light passage opening to form the diaphragm opening,
A blade driving device comprising a suppressing member that suppresses displacement of the blade tip portion in the light passing direction.   The blade driving device according to claim 1, wherein the holding member is an optical member through which light passes.   The blade driving device according to claim 1, wherein the holding member is provided integrally with the drive ring. A cover member that movably accommodates the plurality of diaphragm blades between the base member;
The blade driving device according to claim 1, wherein the holding member is the cover member. On at least the surface of the holding member facing the plurality of diaphragm blades,
5. The blade driving device according to claim 1, wherein at least one of surface treatment of antireflection, antistatic, and sliding coating is performed.   6. The blade driving device according to claim 1, wherein the holding member includes an optical part through which light passes and a light shielding part provided on an outer periphery of the optical part. An optical apparatus comprising the blade driving device according to any one of claims 1 to 6.

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