Light intensity control devices and optical instruments

Abstract

The present invention provides a light intensity control device that facilitates miniaturization of the aperture and optical filter or shutter. [Solution] To solve the above problems, the light intensity adjustment device of the present invention comprises a base member 101 that forms an opening 101a through which light passes; a plurality of aperture blades 116 that move in a direction perpendicular to the optical axis perpendicular to the direction through which light passes, and move back and forth relative to the opening 101a, forming a smaller aperture than the opening 101a; a first drive unit 102 positioned away from the opening 101a and moving the plurality of aperture blades 116 back and forth; a light intensity adjustment member 104 that can move back and forth relative to the opening 101a; a second drive unit 110 that rotates a magnet to operate the light intensity adjustment member; and a partition member 109 that restricts the position of the aperture blades 116 and the light intensity adjustment member in the optical axis direction, wherein the partition member 109 is provided with shafts 109b and 109c for guiding the aperture blades.

Description

Technical Field

[0001] The present invention relates to a light quantity adjustment device mounted on optical devices such as imaging devices and interchangeable lenses. It also relates to an optical device equipped with a light quantity adjustment device.

Background Art

[0002] A light quantity adjustment device mounted on an optical device such as a digital camera or a video camera drives a stepping motor or the like as a drive source, rotates a diaphragm blade through a rotating member configured with gears, and changes the area of the light passage opening to adjust the amount of light passing through the device, or has a moving magnet type electromagnetic drive unit as a drive source and includes a light reduction filter that moves forward and backward in the light passage opening to cover and open the light passage opening. (See Patent Document 1).

[0003] Patent Document 1 discloses a light quantity adjustment device that uses a moving magnet type electromagnetic drive unit as a drive source and moves a shutter blade and a diaphragm blade forward and backward in the light passage opening.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the configuration disclosed in Patent Document 1, since the drive sources of the diaphragm and the shutter and their blades are arranged over the entire circumferential direction, the device is likely to be enlarged over the entire circumferential direction.

[0006] The present invention provides a light quantity adjustment device capable of reducing the size of the device and an optical device equipped with the same.

Means for Solving the Problems

[0007] To solve the above problems, the light intensity adjustment device of the present invention comprises a base member having an opening through which light passes; a plurality of aperture blades that move in a direction perpendicular to the optical axis of the light passing through the opening and advance and reciprocate relative to the opening; a first drive unit positioned away from the opening and advances and reciprocates the plurality of aperture blades; a light intensity adjustment member that advances and reciprocates relative to the opening; a second drive unit that rotates a magnet to operate the light intensity adjustment member; and a partition member that separates the positions of the aperture blades and the light intensity adjustment member in the optical axis direction, wherein the partition member is provided with a guide shaft that guides the aperture blades. [Effects of the Invention]

[0008] According to the present invention, space can be used effectively, and a light intensity adjustment device equipped with a light intensity adjustment member and aperture for light reduction or shading can be made smaller. [Brief explanation of the drawing]

[0009] [Figure 1] Front view of the light intensity control device according to Example 1 [Figure 2] Rear view of the light intensity control device according to Example 1 [Figure 3] Perspective view of the light intensity control device according to Example 1 [Figure 4] Exploded perspective view of the light intensity control device according to Example 1 [Figure 5] Operation diagram of the shutter of the light intensity control device according to Example 1 [Figure 6] Operation diagram of the aperture of the light intensity control device according to Example 1 [Figure 7] Diagram illustrating the relationship between the shutter and guide axis of the light intensity control device according to Example 1. [Figure 8] Front view of the light intensity control device according to Example 2 [Figure 9] Rear view of the light intensity control device according to Example 2 [Figure 10] Exploded perspective view of the light intensity control device according to Example 2 [Figure 11] Operation diagram of the ND vane of the light intensity control device according to Example 2 [Figure 12]Operation diagram of the ND blade of the light quantity adjustment device according to Example 3 [Figure 13] Front view of the light quantity adjustment device according to Example 4 [Figure 14] Rear view of the light quantity adjustment device according to Example 4 [Figure 15] Exploded perspective view of the light quantity adjustment device according to Example 4 [Figure 16] Operation diagram of the aperture of the light quantity adjustment device according to Example 4 [Figure 17] Explanation diagram of the relationship between the shutter and the guide shaft of the light quantity adjustment device according to Example 4 [Figure 18] Schematic diagram of an imaging device equipped with the aperture device of Example 4.

Mode for Carrying Out the Invention

[0010] (Example 1) Embodiments of the present invention will be described in detail with reference to FIGS. 1 to 7.

[0011] FIG. 1 is a front view of a light quantity adjustment device according to an embodiment of the present invention. FIG. 2 shows a rear view of the light quantity adjustment device, FIG. 3 shows a perspective view of the light quantity adjustment device, and FIG. 4 shows an exploded perspective view of the light quantity adjustment device. FIG. 5 shows an operation diagram of the shutter of the light quantity adjustment device, and FIG. 6 shows an operation diagram of the aperture. FIG. 7 is a front view of the light quantity adjustment device according to Example 1, and is a view in which the cover plate 119 and the aperture blade group 116 (117, 118) are omitted.

[0012] In these figures, the base member 101 is a member that supports the structure of the shutter, and a fixed aperture (opening) 101a through which light passes is provided. On the outer surface (one surface in the optical axis direction) of the base member 101, at a position away from the fixed aperture 101a, an aperture drive unit 102 and a shutter drive unit 110, which will be described later, are attached.

[0013] The aperture drive unit 102 is attached to the base member 101 and serves as the drive source for the aperture. The aperture drive unit 102 can use an electromagnetic actuator such as a stepping motor or a galvanometer. The aperture drive unit is equipped with an output shaft 102b, and by electrically controlling the aperture drive unit 102, it is possible to rotate it to any angle.

[0014] The drive arm 103 has blade drive pins 103i and 103j at both ends on either side of the output shaft 102b, which serve as transmission parts for driving the aperture blade group 116 described later. The blade drive pin 103i engages with the aperture blade 117, and the blade drive pin 103j engages with the aperture blade 118. The aperture drive arm 103 is fixed to the output shaft 102b of the aperture drive unit by press-fitting or adhesive, and the aperture drive lever 103 rotates in accordance with the rotation of the output shaft 102b, with the output shaft 102b as the center of rotation.

[0015] The aperture blade group 116 consists of two aperture blades 117 and 118. The aperture blades 117 and 118 are thin, light-shielding plate-like members and have elongated drive holes 117i and 118j through which the blade drive pins 103i and 103j are inserted. The aperture blades 117 and 118 are made by pressing a thin resin sheet coated with a light-shielding paint, pressing a thin metal plate that has been lubricated, or by molding it into a thin plate shape.

[0016] Next, the structure of the shutter section will be explained. The base member 101 is a substrate for the light intensity adjustment device 100, and has a device opening 101a that allows light to pass through.

[0017] The partition member 109 is assembled parallel to the base member 101 and such that the fixed opening 101a and the fixed opening (opening) 109a are coaxial, forming a shutter blade chamber between the base member 101 and the partition member 109 in which the shutter blade group 104 is housed.

[0018] As mentioned above, the shutter drive unit 110 is attached to the outer surface (one side in the optical axis direction) of the base member 101.

[0019] The magnet 111 has two poles (N pole and S pole) magnetized on its outer surface. The shutter drive lever 112 is integrally formed with the magnet 111. Methods for integration include fixing with adhesive or, in the case of resin, insert injection molding. The integrated magnet 111 and shutter drive lever 112 are supported by a drive lever rotation shaft (not shown) provided on the base member 101, and can rotate.

[0020] The stator yoke 113, made of soft magnetic material, is positioned on the outer curved surface of the magnet 111. The electromagnetic coil unit 114 is constructed by winding a coil made of conductive wire around a bobbin. This electromagnetic coil unit 114 is attached to the base member 101 with the stator yoke 113 inserted.

[0021] The actuator cover 115 is attached to the base member 101 and holds the stator yoke 113 and the shutter drive lever 112.

[0022] As shown in the figure, the magnet 111, shutter drive lever 112, stator yoke 113, electromagnetic coil unit 114, and actuator cover 115 are assembled to form an electromagnetic actuator, which becomes the shutter drive unit 110 and drives the shutter blade group 104 described later.

[0023] The shutter blade group 104 consists of multiple shutter blades, and the light intensity adjustment device in this embodiment consists of four shutter blades 105, 106, 107, and 108. As a light intensity adjustment member that is operated by rotating a magnet, the aforementioned shutter blades, aperture blades, or neutral density filters such as ND filters can be used.

[0024] Next, the operation of the shutter will be explained with reference to the diagram. Figure 5(a) shows the shutter blades 105, 106, 107, and 108 retracted from the fixed aperture 101a, which serves as the light passage.

[0025] Figure 5(b) shows the shutter blades 105, 106, 107, and 108 covering the fixed opening 101a, which serves as the light passage.

[0026] The shutter blades 105, 106, 107, and 108 are made of thin, light-shielding plate-like members and have shutter blade rotation holes 105a, 106a, 107a, and 108a and cam holes 105b, 106b, 107b, and 108b. The shutter drive lever 112 is rotated by the shutter drive unit 110, and the shutter blades 105, 106, 107, and 108 rotate around the shutter blade rotation holes 105a, 106a, 107a, and 108a, covering or opening the fixed opening 101a.

[0027] Next, the operation of the aperture will be explained with reference to the diagram. Figure 6(a) shows the aperture blades 117 and 118 retracted from the fixed opening 101a of the aperture base plate, which serves as the light passage.

[0028] When the aperture drive unit 102 is rotated clockwise from the state shown in Figure 6(a), the aperture drive lever 103, which is press-fitted onto the output shaft 102b of the aperture drive unit, rotates, causing the blade drive pins 103i and 103j to rotate clockwise. The aperture blade 117 receives force from the cam hole 117i fitted onto the blade drive pin 103i and moves linearly downward in Figure 6 along the guide holes 117b and 117c fitted onto the guide shafts 109b and 109c provided on the partition member 109. The aperture blade 118 receives force from the cam hole 118j fitted onto the blade drive pin 103j and moves linearly upward in Figure 6 along the guide holes 118b and 118c fitted onto the guide shafts 109b and 109c. The aperture formed by the aperture blades 117 and 118, through which light passes, becomes smaller, and the amount of light passing through the light intensity adjustment device 100 can be reduced.

[0029] Figure 6(b) shows the aperture drive unit 102 rotated further from (a). This allows for a further reduction in the amount of light passing through the light intensity control device 100.

[0030] Figure 6(c) shows the state after further rotation of the aperture drive unit 102 from (b). The aperture blades 117 and 118 close the fixed opening 101a, which is the light passage opening, and block out light.

[0031] By rotating the rotation phase of the aperture drive unit 102 to any position, it becomes possible to change the aperture opening shown in Figures 6(a) to (c) to any area, thereby adjusting the amount of light passing through the light intensity adjustment device 100.

[0032] Furthermore, by rapidly rotating the aperture drive unit 102 from any of the states in Figures 6(a) to (b) to the state in Figure 6(c), the fixed aperture 101a can be shielded from light, making it possible to use it as a shutter device. However, if a galvanometer is used in the aperture drive unit 102, there is a limit to the shutter speed that can be achieved with the aperture blades 117 and 118. Also, as shown in Figure 6(b), the aperture blades 117 and 118 are designed so that the circularity of the aperture shape is high even at intermediate aperture positions, which puts them at a disadvantage in terms of shutter speed compared to the shutter blades 105, 106, 107, and 108.

[0033] Therefore, in order to achieve a reasonably fast shutter speed, shutter blades 105, 106, 107, and 108 are required in addition to aperture blades 117 and 118. Since shutter speed is also related to continuous shooting performance, separating aperture blades 117 and 118 from shutter blades 105, 106, 107, and 108 can improve the camera's continuous shooting performance.

[0034] In this embodiment, the amount of light passing through the light intensity adjustment device 100 is adjusted by the linear movement of the aperture blades 117 and 118 so as to sandwich the fixed aperture 101a. This configuration makes it possible to miniaturize the left-right direction in Figure 6. Hereafter, this left-right direction will be referred to as the width direction. This configuration is advantageous for miniaturization in the above respects compared to the so-called iris diaphragm configuration, in which multiple aperture blades are arranged at equally spaced angles on concentric circles of the fixed aperture. Some compact digital cameras and smartphone cameras employ a periscope (bent optical structure). This involves bending the incident light by 90 degrees and arranging the lens group perpendicular to the optical axis in order to reduce the thickness of the camera or smartphone. In the case of the periscope type, the width direction of the light intensity adjustment device is directly related to the thickness of the camera or smartphone, so the above configuration makes it possible to miniaturize the optical equipment.

[0035] Figure 7 is a front view of the light intensity control device according to Embodiment 1, in which the cover plate 119 and the aperture blade group 116 (117, 118) are omitted.

[0036] Figure 7(a) shows the shutter blades 105, 106, 107, and 108 retracted from the fixed opening 10a, which serves as the light passage.

[0037] Figure 7(b) shows the shutter blades 105, 106, 107, and 108 covering the fixed aperture 101a, which serves as the light passage.

[0038] Conventionally, the guide shafts 109b and 109c for aperture blades 117 and 118 were provided on the base member 101, which meant that the guide shafts had to be installed while avoiding the movable range of the shutter blades 105, 106, 107, and 108.

[0039] In this embodiment, since the guide shafts of aperture blades 117 and 118 are provided on the partition member 109, the shape of the shutter blades 105, 106, 107, and 108 is not dependent on the shape of the shutter blades 105, 106, 107, and 108.

[0040] Guide axes can be installed. Therefore, it is possible to install the guide axes for aperture blades 117 and 118 at a position that overlaps with any of the shutter blades 105, 106, 107, or 108 in a plane perpendicular to the optical axis direction. In addition, in this embodiment, in the lateral direction of Figure 7, guide axes 109b and 109c are positioned on the opposite side from the side where the shutter blades 105, 106, and 107 are retracted from the fixed aperture 101a.

[0041] By arranging the shutter structure and the guide axis of the aperture blades in this way, space can be used effectively, making it possible to reduce the external size of the light intensity adjustment device 100.

[0042] (Example 2) The configuration of the light intensity control device 200 in Example 2 of the present invention will be described in detail with reference to Figures 8 to 11. In the configuration of this embodiment, components the same as those in Example 1 are denoted by the same reference numerals.

[0043] Figure 8 is a plan view of the light intensity control device in Example 2. Figure 9 shows a rear view of the light intensity control device, and Figure 10 shows an exploded perspective view of the light intensity control device. Figure 11 shows the operation diagram of the ND filter.

[0044] In these figures, the aperture drive unit 102, aperture drive lever 103, and aperture blade group 116 are the same as those in the aperture device 100 of Embodiment 1.

[0045] Next, I will explain the structure of the neutral density filter. The neutral density filter is sometimes called an ND (Neutral Density) filter, and will be referred to as an ND filter below.

[0046] The ND drive unit 206 is a moving magnet type drive unit consisting of an electromagnetic coil, similar to the shutter drive unit 110 in Embodiment 1. The ND drive lever 207 rotates together with the magnet 111.

[0047] The ND vane 202 consists of an ND filter 204 that reduces the amount of light passing through and an ND retaining vane 203 that holds the ND filter. The ND vane 202 has a vane rotation hole 203a that fits with the vane rotation shaft 201d of the base member and a cam hole 203b that fits with the ND drive lever 207. The ND vane 202 rotates around the vane rotation hole 203a by the ND drive unit 206, moving forward and backward into the device opening (opening) 201a of the base member, and can reduce the amount of light passing through the device opening 201a.

[0048] In this embodiment, the light intensity adjustment element is an ND filter, but by changing the characteristics of the filter, the same configuration can be used with various optical filters such as IR cut filters and bandpass filters.

[0049] The partition member 205 is mounted parallel to the base member 201, forming an ND vane chamber between the partition member 205 and the base member 201 where the ND vane 202 is housed.

[0050] In this embodiment, since the guide shafts for aperture blades 117 and 118 are provided on the partition member 205, the guide shafts can be installed regardless of the shape of the ND blade 202.

[0051] By arranging the ND structure and aperture blade guide axis in this way, space can be used effectively, making it possible to reduce the external size of the light intensity adjustment device 200.

[0052] (Example 3) The configuration of the light intensity control device 300 in Example 3 of the present invention will be described in detail with reference to Figure 12. In this embodiment, components the same as those in Example 1 or Example 2 are denoted by the same reference numerals.

[0053] Figure 12 shows the operation diagram of the ND filter in the light intensity control device of Example 3.

[0054] Example 3 is a modification of Example 2 in which the ND vane 202 is replaced with an ND vane 302. While the ND vane 202 of Example 2 consisted of an ND filter and an ND retaining vane that held the ND filter, the ND vane 302 has a vane rotation hole 302a and a cam hole 302b that engages with the ND drive lever 207 in the ND filter base material.

[0055] The operating principle is the same as in Embodiment 2. In this embodiment, since the guide shafts for aperture blades 117 and 118 are provided on the partition member 205, the guide shafts can be installed regardless of the shape of the ND blade 302.

[0056] By arranging the ND structure and aperture blade guide axis in this way, space can be used effectively, making it possible to reduce the external size of the light intensity adjustment device 300.

[0057] (Example 4) The configuration of the light intensity control device 400 of Example 4 of the present invention will be described in detail with reference to Figures 13 to 17. In the configuration of this embodiment, components the same as those in Example 1, Example 2, or Example 3 are denoted by the same reference numerals.

[0058] Figure 13 is a front view of the light intensity control device of Example 4. Figure 14 shows a rear view of the light intensity control device, and Figure 15 shows an exploded perspective view of the light intensity control device. Figure 16 shows the operation diagram of the aperture of the light intensity control device. Figure 17 is a front view of the light intensity control device according to Example 4, with the cover plate 419 and aperture blade group 416 (417, 418) omitted.

[0059] In these figures, the aperture drive unit 102, aperture drive lever 103, shutter blade group 104, and shutter drive unit 110 are configured the same as those of the light intensity control device 100 in Embodiment 1.

[0060] The base member 401 is a member that supports the structure of the shutter and has a fixed aperture (opening) 401a that allows light to pass through. The aperture drive unit 102 and the shutter drive unit 110 are attached to the outer surface (one surface in the optical axis direction) of the base member 401 at a position away from the fixed aperture 401a.

[0061] The aperture blade group 416 consists of two aperture blades 417 and 418. The aperture blades 417 and 418 are thin, plate-like members with light-shielding properties and have elongated drive holes 418i and 417j through which the blade drive pins 103i and 103j are inserted. They also have 417b and 418b through which the guide shaft 409b is inserted, and 417c and 418c through which the guide shaft 409c is inserted. The aperture blades 417 and 418 are made by pressing a thin resin sheet coated with a light-shielding paint, pressing a thin metal plate that has been lubricated, or by molding it into a thin plate shape.

[0062] The partition member 409 is assembled parallel to the base member 401 and such that the fixed opening (opening) 401a and the fixed opening (opening) 409a are coaxial, forming a shutter blade chamber between the base member 401 and the partition member 409 in which the shutter blade group 104 is housed.

[0063] The cover plate 419 is assembled parallel to the base member 401 and such that the fixed opening 401a and the fixed opening 419a are coaxial, forming an aperture blade chamber between the partition member 409 and the cover plate 419 in which the aperture blade group 416 is housed.

[0064] The structure and operation of the shutter section are the same as in Embodiment 1. The operation of the aperture will be explained with reference to the figure. Figure 16(a) shows the aperture blades 417 and 418 retracted from the fixed opening 101a of the aperture base plate, which serves as the light passage.

[0065] When the aperture drive unit 102 is rotated counterclockwise from the state shown in Figure 16(a), the aperture drive lever 103, which is press-fitted onto the output shaft 102b of the aperture drive unit, rotates, causing the blade drive pins 103i and 103j to rotate counterclockwise. The aperture blades 418 receive force from the cam hole 418i fitted onto the blade drive pin 103i and move linearly upward in Figure 16 along the guide holes 418b and 418c fitted onto the guide shafts 409b and 409c provided on the partition member 409. The aperture blades 417 receive force from the cam hole 417j fitted onto the blade drive pin 103j and move linearly downward in Figure 16 along the guide holes 418b and 418c fitted onto the guide shafts 409b and 409c. The aperture formed by the aperture blades 417 and 418, through which light passes, becomes smaller, and the amount of light passing through the light intensity adjustment device 400 can be reduced.

[0066] Figure 16(b) shows the state after further rotation of the aperture drive unit 102 from (a). The amount of light passing through the light intensity control device 400 can be further reduced.

[0067] Figure 16(c) shows the state after further rotation of the aperture drive unit 102 from (b). The aperture blades 417 and 418 close the fixed opening 101a, which is the light passage opening, and block out light.

[0068] By rotating the rotation phase of the aperture drive unit 102 to any position, it becomes possible to change the aperture opening shown in Figures 16(a) to (c) to any area, thereby adjusting the amount of light passing through the light intensity adjustment device 400.

[0069] Furthermore, by rapidly rotating the aperture drive unit 102 from any of the states shown in Figures 16(a) to (b) to the state shown in Figure 16(c), the fixed aperture 401a can be shielded from light, thereby allowing it to be used as a shutter device.

[0070] Figure 17 is a front view of the light intensity control device according to Embodiment 4, in which the cover plate 419 and the aperture blade group 416 (417, 418) are omitted.

[0071] Figure 17(a) shows the shutter blades 105, 106, 107, and 108 retracted from the fixed aperture 401a, which serves as the light passage.

[0072] Figure 17(b) shows the shutter blades 105, 106, 107, and 108 covering the fixed aperture 401a, which serves as the light passage.

[0073] In this embodiment, the partition member 409 has guide shafts 409b and 409c positioned on the side where the shutter blades 105, 106, and 107 are retracted from the fixed opening 401a, as shown in the lateral direction of Figure 17.

[0074] In this embodiment, shutter blades 105, 106, and 107 are retracted to the left of the fixed opening 401a, and shutter blade 108 is retracted to the upper side of the fixed opening 401a. Therefore, in the lateral direction of Figure 17, the outer shape on the left side of the fixed opening 401a tends to be larger. By installing the guide shafts 409b and 409c in the direction in which the shutter blades are retracted relative to the fixed opening 401a, it becomes possible to effectively utilize the space to lay out the guide holes for the aperture blades 417 and 418. This makes it possible to reduce the outer shape of the right side of the device where the guide shafts 409b and 409c are not installed.

[0075] Similar to Embodiment 1, in this embodiment as well, the guide axes for aperture blades 117 and 118 are provided on the partition member 109, so that the guide axes can be installed regardless of the shape of the shutter blades 105, 106, 107, and 108. For this reason, it is also possible to install the guide axes for aperture blades 117 and 118 at a position that overlaps with any of the shutter blades 105, 106, 107, or 108 in a plane perpendicular to the optical axis direction.

[0076] By arranging the shutter structure and the guide axis of the aperture blades in this way, space can be used effectively, making it possible to reduce the external size of the light intensity adjustment device 400.

[0077] (Example 5) Figure 18 shows the internal configuration of an interchangeable lens 421 for an interchangeable lens camera, which is an imaging device equipped with the light intensity adjustment device 400 described in Example 4, and the camera body to which the interchangeable lens is attached. The light intensity adjustment device 400 may be the light intensity adjustment device 100 described in Example 1, the light intensity adjustment device 200 described in Example 2, or the light intensity adjustment device 300 described in Example 3.

[0078] The barrel of the interchangeable lens 421 houses a photographic optical system including a variable magnification lens 432, a light intensity adjustment device 400 (which includes an aperture, shutter, and ND filter, as described in the third embodiment), and a focusing lens 429.

[0079] The image sensor 425, composed of photoelectric conversion elements such as a CCD sensor or CMOS sensor, is located inside the camera body and outputs an electrical signal by photoelectric conversion of the subject image formed by the interchangeable lens 421. By changing the aperture of the light intensity adjustment device 400, controlling the timing of the movement of the shutter blade group 104, or moving the aperture blade group 416, the brightness of the subject image formed on the image sensor 425 (i.e., the amount of light reaching the image sensor 425) can be appropriately set.

[0080] The electrical signal output from the image sensor 425 is converted into a digital signal in the image processing circuit 426 and subjected to various image processing steps. This generates an image signal.

[0081] The user can perform zooming by rotating the zoom ring 431 to move the variable magnification lens 432. The controller 422 detects the contrast of the image signal and controls the focus motor 428 according to the contrast to move the focus lens 429 and perform autofocus. Alternatively, the controller 422 may control the focus motor 428 and move the focus lens 429 to perform autofocus based on the detection signal of a focus detection means using a phase difference detection method (not shown).

[0082] Furthermore, the controller 422 controls the aperture drive unit 102, shutter drive unit 110, and ND drive unit 206 of the light intensity adjustment device 400 based on the photometric value of a photometric means (not shown) or the image signal, thereby adjusting the amount of light. This makes it possible to create natural-looking bokeh and ghosting during shooting, and to record high-quality images.

[0083] Furthermore, the present invention is not limited to the interchangeable lens type camera described above, but can be broadly applied to optical devices such as digital cameras with integrated lenses, video cameras, and cameras built into smartphones.

[0084] The embodiments described above are merely representative examples, and when implementing the present invention, each embodiment may be used. Various transformations and modifications are possible. [Explanation of symbols]

[0085] 100, 200, 300, 400 light intensity adjustment device 101, 201, 301, 401 Base members 105, 106, 107, 108 Shutter blades 109 Partition Member 109a Fixed aperture 109b Guide axis, 109c Guide axis 110 Shutter drive unit 111 Magnets 117, 118, 417, 418 aperture blades

Claims

1. A base member having an opening through which light passes, Multiple aperture blades move in a direction perpendicular to the optical axis of the light passing through the opening and advance and retract relative to the opening, A first drive unit is positioned away from the aforementioned opening and moves the plurality of aperture blades back and forth, A light intensity adjusting member that moves forward and backward relative to the opening, A second drive unit that rotates the magnet to operate the light intensity adjustment member, The device comprises the aperture blades and a partition member that separates the positions of the light intensity adjustment member in the optical axis direction, The partition member is provided with a guide shaft that guides the aperture blades. A light intensity control device characterized by the following features.

2. The light intensity adjustment device according to claim 1, characterized in that the plurality of aperture blades move linearly so as to sandwich the opening.

3. The light intensity adjustment member is a plurality of shutter blades, The light intensity adjustment device according to claim 1, characterized in that the guide shaft is provided in a direction perpendicular to the direction in which the aperture blades operate, on the opposite side of the direction in which at least one of the plurality of shutter blades retracts from the opening.

4. The light intensity adjustment member is a plurality of shutter blades, The light intensity adjustment device according to claim 1, characterized in that the guide shaft is provided on the same side as the direction in which at least one of the plurality of shutter blades retracts from the opening, in a direction perpendicular to the direction in which the aperture blades operate.

5. The light intensity adjustment member is a light-reducing filter. The light intensity adjustment device according to feature 1.

6. The light intensity adjustment device according to claim 1, characterized in that at least one of the two guide axes overlaps with the light intensity adjustment member in the optical axis direction.

7. An optical instrument comprising a light intensity adjustment device according to any one of claims 1 to 6, and an image sensor for imaging light that has passed through the light intensity adjustment device.

Images