JP2014134749A - Light quantity adjustment device and optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light quantity adjustment device and optical instrument capable of being downsized while the malfunction of a light quantity adjustment member is prevented.SOLUTION: The light quantity adjustment device 300 includes: a blade presser plate 9 as a lens insertion opening formation member for forming a presser plate opening 9a serving as a lens insertion opening into which a part of a lens system of an optical instrument or the like is inserted; and a light quantity adjustment blade 7 as a light quantity adjustment member for adjusting the light quantity in the presser plate opening 9a. A crossing angle 10 is substantially formed by an outer peripheral edge of the light quantity adjustment blade 7 and an end of the pressure plate opening part 9a.

Description

  The present invention relates to a light amount adjusting device used in an optical imaging device such as a digital camera, and an optical device equipped with the light amount adjusting device.

  2. Description of the Related Art Conventionally, an electronic camera has been widely used in which a subject is imaged on an image sensor such as a CCD image sensor to obtain image data representing the subject. Cameras are generally required to be portable, and the lens barrel that holds the taking lens is also retracted to the camera body side when not in use, and is configured to protrude forward from the camera body side when taking a picture. Compact digital cameras with retractable, retractable lens barrels have been provided. In compact digital cameras, a light amount adjusting device such as a lens shutter or a diaphragm disposed between photographing lenses is widely used.

  For such a lens barrel that can be retracted and extended and that has a lens shutter or aperture, it is required to improve the portability by reducing the optical axis direction of the lens barrel when retracted. It has been.

  As a solution to this, a light amount control device that is in a use state in which the amount of photographing light passing through a photographing lens is controlled in a photographing state, and in an unused state in which the opening is kept open to a predetermined opening diameter in the housed state. When moving from the shooting state to the retracted state, a state in which at least part of the members constituting any one of the plurality of lens groups constituting the photographing lens has entered the opening of the light amount adjustment device And a lens moving mechanism that moves the lens (see Patent Document 1).

JP 2004-347615A

  Here, in the optical apparatus having a lens moving mechanism for inserting a part of the lens system into the opening of the light amount adjusting device when changing from the photographing state to the retracted state, the opening diameter of the light amount adjusting device is made larger than the lens diameter. Accordingly, it is necessary to prepare a light amount adjusting blade having a size sufficient to cover the opening of the light amount adjusting device. However, since the optical device is provided with a relatively large light amount adjustment blade, not only the size of the device is increased, but also the force required for driving increases as the light amount adjustment blade increases. In addition, when an impact is applied to the light amount adjusting device due to dropping of an optical product such as a camera, the possibility of causing a malfunction is increased. On the other hand, if the outer shape of the light amount adjusting blade is simply reduced, the light amount adjusting blade may be caught at the end (opening edge) of the opening of the light amount adjusting device in the opening / closing operation of the blade, causing a malfunction.

  An object of the present invention is to provide a light amount adjusting device and an optical apparatus that can realize further miniaturization while preventing malfunction of a light amount adjusting member.

  The present invention that solves the above-described problems includes a lens insertion opening forming member that forms a lens insertion opening, and a light amount adjustment member that adjusts the amount of light in the lens insertion opening, and an outer peripheral edge of the light amount adjustment member and the lens The light amount adjusting device is characterized in that an end portion of the insertion opening substantially forms an intersection angle. Thereby, further miniaturization is realizable, preventing the malfunctioning of the light quantity adjustment member.

  In the present invention, the light amount adjustment member is provided so as to be movable in a direction intersecting the optical axis direction with respect to the lens insertion opening, and the width of the light amount adjustment portion of the light amount adjustment member that moves into the lens insertion opening. Is preferably smaller than the width of the lens insertion opening. Thereby, the external shape of the light amount adjusting member is substantially reduced, and the apparatus can be easily downsized.

  Further, in the present invention, the light amount adjustment member is provided so as to be movable in a direction intersecting the optical axis direction with respect to the lens insertion opening, and an entry direction in which the light amount adjustment member enters the lens insertion opening in an outer peripheral edge portion of the light amount adjustment member It is preferable that the rear end of the lens and the end of the lens insertion opening substantially form a crossing angle. Thereby, even if the external shape of the light amount adjusting member is substantially reduced, stable movement of the light amount adjusting member is ensured, and it is possible to effectively prevent malfunction of the light amount adjusting member.

  Further, in the present invention, the light amount adjusting member is provided such that one end thereof is connected to the driving means and is movable in a direction intersecting the optical axis direction with respect to the lens insertion opening, and the other end of the light amount adjusting member Preferably, the portion extends beyond the end of the lens insertion opening until reaching the opening edge. As a result, stable movement of the light amount adjusting member is ensured, and it is possible to further prevent malfunction of the light amount adjusting member.

  Furthermore, in the present invention, when the light amount adjusting member does not cover the entire region of the lens insertion opening in a state where the light amount adjusting member has entered the lens insertion opening, the light amount adjusting member is retracted from a position in the lens insertion opening. It is preferable that the light amount adjusting member connected to the driving means is gradually retracted from the connection portion side. As a result, the slidable contact portion between the light amount adjusting member and the peripheral edge portion of the lens insertion opening gradually increases, so that stable movement of the light amount adjusting member is ensured, and malfunction of the light amount adjusting member can be further prevented. .

  In the present invention, the light amount adjusting member is formed of a plate-shaped blade member, and the shape of the blade edge portion serving as the outer peripheral edge portion of the light amount adjusting member is close to the blade rotation center from the opening center of the lens insertion opening. It is preferable to form from the circular arc shape which has a center in. As a result, stable movement of the light amount adjusting member is ensured, and it is possible to further prevent malfunction of the light amount adjusting member.

  In the present invention, it is preferable that the light amount adjusting member is formed of a blade member holding an optical filter. Thereby, the light quantity adjustment apparatus which can adjust light quantity with an optical filter is realizable.

  According to the present invention, further downsizing can be realized while preventing malfunction of the light amount adjusting member.

The disassembled perspective view which shows the principal part of the light quantity adjustment apparatus which concerns on 1st embodiment of this invention. The top view of the light quantity adjustment blade used for the light quantity adjustment apparatus of FIG. The top view which shows the state which the light quantity adjustment blade of the light quantity adjustment apparatus of FIG. 1 has evacuated from the opening. The top view which shows the state in which the light quantity adjustment blade | wing of the light quantity adjustment apparatus of FIG. 1 has approached the aperture. The top view which shows the state in the middle of operation | movement which the light quantity adjustment blade | wing of the light quantity adjustment apparatus of FIG. FIG. 6 is a plan view showing a state in which the retraction operation of the light amount adjustment blade of the light amount adjustment device in FIG. 5 is slightly advanced from FIG. 5. The top view which shows the state which the retraction | saving operation | movement of the light quantity adjustment blade | wing of the light quantity adjustment apparatus of FIG. 6 advanced a little from FIG. 1 is a perspective view of an external appearance of a camera equipped with a light amount adjusting device according to the present invention in a state where a lens barrel is swung. 1 is an external perspective view of a camera equipped with a light amount adjusting device according to the present invention in a state where a lens barrel is extended. Sectional drawing which follows the optical axis S in the retracted state of the camera shown to FIG. 5, FIG.

  As will be described in detail later, the light amount adjusting device according to the present invention includes a lens insertion opening forming member that forms a lens insertion opening into which at least a part of a lens system such as an optical device can be inserted, and adjusts the light amount in the lens insertion opening. The outer peripheral edge portion of the light amount adjusting member and the end portion of the lens insertion opening substantially form an intersection angle. For example, in the process of moving the light amount adjustment member relative to the lens insertion opening in a direction intersecting the optical axis direction, an intersection angle is formed between the outer peripheral edge of the light amount adjustment member and the end of the lens insertion opening. To do. Accordingly, it is possible to effectively prevent malfunction such as the outer peripheral edge of the light amount adjusting member being caught by the end portion of the lens insertion opening while reducing the size of the light amount adjusting member.

  Hereinafter, a camera provided with an embodiment of a light amount adjusting device according to the present invention will be described with reference to FIGS.

  8 and 9 are external perspective views of the camera 500 provided with the light amount adjusting device of the present invention. FIG. 8 shows the retracted state of the lens barrel 100 containing the lens group, and FIG. 9 shows the extended state of the lens barrel 100.

  The lens barrel 100 of the camera 500 shown in FIGS. 8 and 9 incorporates a zoom lens (not shown), and the focal length adjustment and the focus adjustment are performed by moving these lens groups in the optical axis direction. Done.

  FIG. 10 is a cross-sectional view along the optical axis S in the retracted state of the lens barrel of the camera shown in FIGS.

  The lens barrel 100 can be retracted and extended between the retracted state shown in FIG. 8 and the extended state shown in FIG. In the lens barrel 100, a light amount adjusting device 300 is disposed between lens groups constituting the photographing lens. Examples of the light amount adjusting device include a lens shutter and a diaphragm device.

  In addition, the light amount adjusting device 300 (specifically, in the opening) has a structure in which a part of the lens group 200 is inserted in the retracted state, that is, the camera is not used, and the dimension in the optical axis direction in the retracted state is shortened. can do.

  Hereinafter, an embodiment of a light amount adjusting device according to the present invention will be described in detail with reference to FIGS.

  FIG. 1 is an exploded perspective view showing a main part of the light amount adjusting device 300. FIG. 2 is a plan view of a light amount adjusting blade used in the light amount adjusting device. FIG. 3 is a view showing the inside of the blade chamber, and is a plan view showing a state in which the light amount adjusting blade is retracted from the opening. 4 is a view showing the inside of the blade chamber as in FIG. 3, and is a plan view showing a state in which the light quantity adjusting blade enters the aperture. FIG. 5 is a plan view showing a state in the middle of the operation in which the light quantity adjusting blade is retracted from the opening. FIG. 6 is a plan view showing a state in which the light amount adjusting blade is retracted from the opening as in FIG. FIG. 7 is a plan view showing a state in which the light amount adjusting blade is in the middle of the operation of retracting from the opening as in FIGS.

  In these drawings, reference numeral 1 denotes a ground plate (device substrate), which includes an opening 1a, a lever rotation shaft 1b, a blade rotation shaft 1c, and blade stoppers 1d and 1e. The opening 1a serves as a light passage opening (optical path) of the camera and escapes the lens group when the camera is not used. That is, the opening 1a is a lens insertion opening into which at least a part of the lens group is inserted. Further, the blade stoppers 1d and 1e have a structure for stopping the rotation operation of the light amount adjusting blade 7 described later.

  Reference numeral 2 denotes a magnet whose outer peripheral surface is magnetized to two poles (N pole and S pole). Reference numeral 3 denotes a drive lever, which is configured integrally with the magnet 2. Examples of the integration method include fixing by an adhesive and, if a resin, insert injection molding. The integrally configured magnet 2 and drive lever 3 are supported by a lever rotation shaft 1b provided on the main plate 1 and can rotate.

  Reference numeral 4 denotes a stator yoke made of a soft magnetic material. The stator yoke 4 is disposed on the outer peripheral curved surface of the magnet 2. Reference numeral 5 denotes an electromagnetic coil unit, which is configured by winding a coil made of a conductive wire around a bobbin. The electromagnetic coil unit 5 is attached to the ground plane 1 with the stator yoke 4 inserted. An actuator cover 6 is attached to the main plate 1 and holds the stator yoke 4 and the drive lever 3.

  As shown in the drawing, the magnet 2, the drive lever 3, the stator yoke 4, the electromagnetic coil unit 5, and the actuator cover 6 are assembled to constitute an electromagnetic actuator as a drive source of the light amount adjusting device, and these are light amount adjusting members. It becomes a drive means of a certain light quantity adjusting blade 7. This electromagnetic actuator drives a light quantity adjusting blade 7 described later.

  Reference numeral 7 denotes a light amount adjusting blade, which rotates by the electromagnetic actuator and opens and closes the optical aperture 13 of the light amount adjusting device 300. This optical aperture 13 communicates substantially with the aperture into which the lens is inserted. Reference numeral 9 denotes a blade pressing plate, which includes a pressing plate opening (lens insertion opening) 9a. The blade pressing plate 9 is a pressing plate that is disposed to face the base plate 1 to form a travel space (moving space) for the light amount adjusting blade 7 and restrict the movement of the light amount adjusting blade 7 in the optical axis direction. The presser plate opening 9a is a light passage port of the camera like the opening 1a of the base plate, and also escapes the lens group when the camera is not used. The optical aperture 13 is a passage through which a light beam of a camera on which the light amount adjusting device 300 is mounted.

  Note that, as shown in FIG. 10, a part of the lens group 200 enters the holding plate opening (lens insertion opening) 9a in the retracted state, that is, when the camera is not used. It is formed with a large size opening.

  Here, the structure of the light quantity adjusting blade 7 will be described in detail with reference to FIGS.

  As shown in the figure, the light amount adjusting blade 7 is composed of a rotation shaft hole 7a, a hole portion 7b, a blade opening 7c, and a curved portion 7d. The rotation shaft hole 7a is fitted to the blade rotation shaft 1c, and the hole 7b is fitted to the drive lever pin 3b. A light-reducing filter 8, which is one of optical filters, is attached to the light amount adjustment blade 7 so as to cover the blade opening 7 c of the light amount adjustment blade 7 and operates integrally. The neutral density filter 8 is made of a sheet material that has been surface-treated so as to reduce the amount of transmitted light and not reflect light. The light quantity adjusting blade 7 of the present embodiment has a structure in which a base material serving as a base and a neutral density filter 8 are attached to the base material while being shifted by a predetermined amount in the surface direction. A structure in which a predetermined amount protrudes from the base material is adopted.

  The outer shape of the light quantity adjusting blade 7 has a curved portion 7d. The curved portion 7d is defined by an arc in which the arc center of each minute section is located closer to the rotation shaft hole 7a than the center of the blade opening 7c. As a result, stable movement of the light amount adjusting member is ensured, and it is possible to further prevent malfunction of the light amount adjusting member.

  Further, in the present embodiment, as described above, the light amount adjusting blade 7 is provided so as to be movable in the direction intersecting the optical axis direction with respect to the pressing plate opening 9a. The width of the light amount adjustment portion that moves into the opening 9a is smaller than the width of the pressing plate opening 9a. Thereby, the light quantity adjustment blade 7 forms a state in which at least a part of the pressing plate opening 9a is not blocked when the pressing plate opening 9a is opened and closed.

  Further, in the present embodiment, the light quantity adjusting blade 7 has the other end on the side opposite to the one end connected to the driving source (driving means), that is, the neutral density filter 8 protruding from the base member. It extends beyond the end of the opening 9a until it reaches the opening edge. The neutral density filter 8 is configured to slide toward the ground plate 1 facing the holding plate opening 9, thereby ensuring stable movement of the light amount adjusting blade 7 and preventing malfunction of the light amount adjusting blade 7. Further prevention is possible.

  When the electromagnetic coil unit 5 is energized in the light quantity adjusting device 300 having the above configuration, the magnet 2 and the drive lever 3 rotate according to the energizing direction by the magnetic action with the stator yoke 4, and accordingly, the light quantity adjusting blade 7. Since the drive lever 3 inserted through the hole 7b rotates, the light quantity adjusting blade 7 rotates in the rotation direction from the retracted state of FIG. 3 to the aperture entering state of FIG. 4 around the rotation shaft hole 7a. . On the other hand, when the electromagnetic coil unit 5 is reversely energized, the magnet 2 rotates in the reverse direction and the drive lever 3 also rotates in the reverse direction, so that the light quantity adjusting blade 7 is in the retracted state in FIG. Rotate until.

  In such an opening / closing operation of the light quantity adjustment blade 7, a non-light-shielding region is provided between the light quantity adjustment blade 7 and the base plate opening 1a or the pressing plate opening 9a in a state where the light quantity adjustment blade 7 enters the opening. 11 and 12 are formed. The non-shielding regions 11 and 12 are shielded in the optical axis direction by components other than the light amount adjusting device 300 constituting the lens barrel 100. When the light amount adjusting device 300 is mounted on an optical device such as a camera, the light beam condensed by the lens passes through the optical aperture diameter 13. Further, when the light amount adjusting blade 7 enters the light passage opening, the condensed light beam is dimmed through the blade opening 7 c of the light amount adjusting blade 7.

  Thus, since the light quantity adjustment blade 7 does not cover the entire pressing plate opening 9a, the outer shape of the light quantity adjustment blade 7 can be substantially reduced. As a result, the space required for retraction is reduced, and as a result, the radial direction of the light amount adjusting device 300 can be reduced in size.

  In addition, since the light amount adjustment blade 7 can be configured to have a small outer shape and a light weight, a small drive unit can exert a sufficient force, and the drive actuator can be downsized.

  Here, the light quantity adjusting blade 7 operates while rubbing against the ground plate 1 and the blade pressing plate 9 forming the blade traveling space by receiving the warp of the material and the air resistance in the rotating operation. Further, when entering the base plate opening 1a or the pressing plate opening 9a, there is a possibility that due to the same factors, only the entry portion may protrude from the blade travel space in the optical axis direction rather than the respective surfaces. If the light amount adjusting blade 7 is retracted in such a state, it may hit the edge of the pressing plate opening 9a and cause a malfunction.

  The state during the opening operation in this embodiment will be described in detail below.

  FIG. 5 is a plan view showing a state in the middle of the operation in which the light amount adjusting blade 7 is retracted from the optical aperture diameter 13. The light quantity adjusting blade 7 rotates counterclockwise in the figure around the rotation shaft hole 7a. At this time, the curved portion 7d of the light amount adjusting blade 7 and the pressing plate opening 9a have an intersection angle 10.

  FIG. 6 shows a state in which the light amount adjusting blade 7 is in the middle of the operation of being retracted from the opening as in FIG. Similarly, at this time, the curved portion 7d of the light quantity adjusting blade 7 and the pressing plate opening 9a have an intersection angle 10.

  FIG. 7 shows a state in which the light amount adjusting blade 7 is further retracted. Similarly, at this time, the curved portion 7d of the light amount adjusting blade 7 and the pressing plate opening 9a have an intersection angle 10.

  As shown in FIGS. 5 to 7, when the light amount adjusting blade 7 moves in a direction intersecting the optical axis direction with respect to the pressing plate opening 9 a, the light amount adjusting blade 7 is moved to the pressing plate opening 9 a out of the outer peripheral edge of the light amount adjusting blade 7. The rear end portion in the entering direction to enter and the end portion of the pressing plate opening 9a are provided so as to form an intersection angle 10 substantially. As a result, the curved portion 7d of the light amount adjusting blade 7 and the end portion of the pressing plate opening 9a always have an angle of a certain amount or more, and the pressing plate opening 9a gradually starts from the side closer to the rotation shaft hole 7a of the light amount adjusting blade 7. Evacuate outside. The rotating shaft hole 7a of the light quantity adjusting blade 7 is sandwiched between the base plate 1 and the blade holding plate 9, and even if the light quantity adjusting blade 7 protrudes from the blade traveling space in the optical axis direction, it is within the blade traveling space range by the scissors. The light amount adjusting blade 7 can be opened without being caught while the shape of the light amount adjusting blade 7 is reduced. In the closing operation of the light amount adjusting blade 7, a stable operation can be realized as in the above opening operation.

  As described above, the lens barrel equipped with the light amount adjusting device of the present invention is in a state in which a part of the lens group enters the opening of the light amount control device in an unused state, as in the prior art. While having the function of shortening the lens barrel in the housed state, even when a small light quantity adjustment blade 7 is provided, stable operation is possible without being caught by the openings of the ground plate and the blade presser plate constituting the blade chamber. A possible light amount adjusting device can be provided.

  Specifically, in the present embodiment, when adjusting the light amount of the pressing plate opening 9a that is a lens insertion opening into which at least a part of a lens system such as an optical device can be inserted using the light amount adjusting blade 7, the pressing plate Compared to the width of the opening 9a, the width of the light amount adjustment portion of the light amount adjustment blade 7 that moves into the holding plate opening 9a is made smaller, and the outer peripheral edge of the light amount adjustment blade 7 and the end of the holding plate opening 9a. The light amount adjusting blade 7 is gradually retracted at an angle of a certain amount or more with the end of the pressing plate opening 9a. It is possible to effectively prevent malfunction such as the outer peripheral edge of the light amount adjusting blade 7 being caught at the end of the plate opening 9a. Thus, in this embodiment, further miniaturization can be realized while preventing malfunction of the light amount adjustment blade 7. The term “miniaturization” as used herein refers to reducing the size of the light amount adjusting device 300 on which the light amount adjusting blade 7 is mounted or the optical apparatus on which the light amount adjusting device 300 is mounted, in addition to reducing the size of the light amount adjusting blade 7. Is included.

  In addition, although the light quantity adjustment apparatus 300 in this embodiment is a light-reducing blade with a filter attached thereto, the entire blade may be configured with a filter member or may have a small aperture diameter. Furthermore, it is applicable to a plurality of light shielding blades and can also be used in a shutter device.

  Here, in the light amount adjusting device of the present invention, the light amount adjusting member has been described by exemplifying a neutral density filter. However, for example, it may be a lens shutter, and is a diaphragm member that changes the area of the light passage opening. It may be a filter member that attenuates the amount of light passing through the light passage port, or may be a member that combines two or more of the shutter member, the diaphragm member, and the filter member.

DESCRIPTION OF SYMBOLS 1 Ground plate 1a Opening part 1b Lever rotating shaft 1c Blade rotating shaft 1d, 1e Blade stopper 2 Magnet 3 Driving lever 3a Lever rotating shaft hole 3b Driving lever pin 4 Stator yoke 5 Electromagnetic coil unit 6 Actuator cover 7 Light quantity adjusting blade 7a Rotary shaft hole 7b Hole 7c Blade opening 7d Curved portion 8 Neutral filter 9 Blade holding plate 9a Holding plate opening 10 Crossing angle 11 Non-shielding region 12 Non-shielding region 13 Optical aperture diameter 100 Lens barrel 200 Lens group 300 Light quantity adjusting device 500 Camera

Claims (8)

  A lens insertion opening forming member that forms the lens insertion opening; and a light amount adjustment member that adjusts the amount of light in the lens insertion opening. The outer peripheral edge of the light amount adjustment member and the end of the lens insertion opening are substantially A light amount adjusting device characterized in that an intersection angle is formed on the light source.   The light amount adjusting member is provided so as to be movable in a direction intersecting the optical axis direction with respect to the lens insertion opening, and a rear end portion in an approach direction entering the lens insertion opening among outer peripheral edges of the light amount adjusting member and the An apparatus for adjusting light quantity, wherein an end of the lens insertion opening substantially forms an intersection angle.   The light amount adjusting member is provided so as to be movable in a direction intersecting the optical axis direction with respect to the lens insertion opening, and the width of the light amount adjusting portion of the light amount adjusting member that moves into the lens insertion opening is the lens insertion opening. The light amount adjusting device according to claim 1, wherein the light amount adjusting device is smaller than the width of the light amount.   The light amount adjusting member is provided such that one end side of the light amount adjusting member is connected to a driving unit and is movable in a direction intersecting the optical axis direction with respect to the lens insertion opening. The light amount adjusting device according to any one of claims 1 to 3, wherein the light amount adjusting device extends beyond an end of the opening until reaching an opening edge.   When the light amount adjusting member does not cover the entire area of the lens insertion opening in a state where the light amount adjusting member enters the lens insertion opening, the light amount adjusting member is connected to a driving unit when retracting from the position in the lens insertion opening. 5. The light amount adjusting device according to claim 1, wherein the light amount adjusting member is gradually retracted from a connection portion side of the light amount adjusting member. The light amount adjusting member is formed from a plate-shaped blade member,
6. The shape of a blade edge portion which is an outer peripheral edge portion of the light amount adjusting member is formed in an arc shape having a center at a position close to the blade rotation center from the opening center of the lens insertion opening. The light quantity adjusting device described in 1.   The light quantity adjusting device according to any one of claims 1 to 6, wherein the light quantity adjusting member is formed of a blade member holding an optical filter. An optical apparatus comprising the light amount adjusting device according to any one of claims 1 to 7.

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