JP2017058443A - Light amount controller, imaging apparatus, and optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in which it is difficult to design a thin light amount controller in a light passing direction to secure clearance of light amount controlling blades.SOLUTION: A light amount controller includes: a plurality of light amount controlling blades having substrate parts in which revolving shafts and operation shafts are provided upright and blade plate parts; a first member rotatably supporting each of the revolving shafts of the plurality of light amount controlling blades juxtaposed in a circular ring shape around a predetermined center opening; and a second member that moves each of the operation shafts of the plurality of light amount controlling blades, rotates each of the light amount controlling blades about each of the revolving shafts, and changes a shielding amount of the center opening made by the plurality of light amount controlling blades and thereby changing the amount of light passing through the center opening. The light amount controlling blade is arranged in a state where at least one portion of the blade plate part overlaps with its adjacent blade plate part of another light amount controlling blade in a light passing direction. The blade plate part is formed inclined to the substrate part in at least its portion overlapping with the blade plate part of another light amount controlling blade.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a light amount adjusting device that adjusts a light amount, and a photographing apparatus and an optical apparatus that include the light amount adjusting device.

  Optical apparatuses such as photographing apparatuses are provided with a light amount adjusting device that adjusts the amount of light reaching the imaging surface such as an image sensor and the depth of field by changing the aperture stop. A specific configuration of this type of light amount adjusting device is described in Patent Document 1, for example.

  The light amount adjusting device described in Patent Document 1 includes a plurality of light amount adjusting blades having a base portion and a blade portion integrally formed of synthetic resin. When the light amount adjusting device is in an open state, the blade portion is formed such that a portion overlapping with the base portion of another adjacent light amount adjusting blade in the light passing direction is thinner than the thickness of the base portion.

JP 2008-203576 A

  However, in the configuration described in Patent Document 1, since the light quantity adjusting blade is disposed between the two members (the rotating member and the cam member), at least a clearance obtained by adding the plate thicknesses of the base portion and the blade portion in the light passing direction is ensured. There is a need. Therefore, it is pointed out that it is difficult to design the light amount adjusting device thin in the light passing direction.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a light amount adjusting device suitable for designing a thin shape in the light passing direction, and a photographing apparatus and an optical apparatus including the light amount adjusting device. Is to provide.

  A light amount adjusting apparatus according to an embodiment of the present invention includes a plurality of plate-like substrate portions on which a rotation shaft and an operation shaft are erected, and a plate-like blade plate portion formed integrally with the substrate portion. A light quantity adjusting blade, a first member having a predetermined center opening, and rotatably supporting each rotation shaft of the plurality of light quantity adjusting blades arranged in a ring around the center opening; and a plurality of light quantities By moving the operating shafts of the adjusting blades, the light amount adjusting blades are rotated around the rotation shafts, and the shielding amount of the central opening by the plurality of light amount adjusting blades is changed to pass through the central opening. A second member that changes the amount of light. The light quantity adjustment blade is arranged in a state in which at least a part of the blade plate portion is overlapped with the blade plate portion of another adjacent light quantity adjustment blade in the light passing direction. The blade plate portion is formed to be inclined with respect to the substrate portion at least in a portion overlapping with the blade plate portion of another light quantity adjustment blade.

  In one embodiment of the present invention, the slat may be formed thinner than the substrate.

  Further, in one embodiment of the present invention, the slat plate portion does not protrude from the surface including the first surface of the substrate portion in the thickness direction of the substrate portion, and is a second surface opposite to the first surface. It is good also as a structure which has a shape which does not protrude from the surface containing.

  Further, in one embodiment of the present invention, the blade plate portion is located at the same position as the surface including the first surface in the plate thickness direction of the substrate portion, and the tip of the blade plate portion. It is good also as a structure located in the substantially same position as the surface containing 2nd surface.

  Moreover, in one Embodiment of this invention, a blade board part may be formed in flat form or non-planar shape.

  In one embodiment of the present invention, the blade portion may be formed so that at least the edge on the opening shaft side that defines the aperture opening is parallel to the substrate portion.

  Moreover, the imaging device which concerns on one Embodiment of this invention is equipped with said light quantity adjustment apparatus.

  Moreover, the optical apparatus which concerns on one Embodiment of this invention is equipped with said light quantity adjustment apparatus.

  According to an embodiment of the present invention, a light amount adjustment device suitable for designing a thin shape in the light passing direction, and an imaging device and an optical apparatus including the light amount adjustment device are provided.

It is a block diagram which shows the structure of the imaging device which concerns on one Embodiment of this invention. It is a disassembled perspective view which shows the structure of the light quantity adjustment apparatus with which the imaging device which concerns on one Embodiment of this invention is equipped. It is a perspective view of the light quantity adjustment blade | wing with which the light quantity adjustment apparatus which concerns on one Embodiment of this invention is equipped. FIG. 4 is a diagram (FIG. 4A) showing a state in which the light amount adjusting blade has narrowed down to a minimum opening diameter in one embodiment of the present invention, and a diagram showing a fully opened state (FIG. 4B). It is a top view (Drawing 5 (a)) and a side view (Drawing 5 (b)) of a light quantity adjustment blade concerning one embodiment of the present invention.

  An imaging apparatus according to an embodiment of the present invention will be described below with reference to the drawings. In the following, a compact digital camera will be described as an embodiment of the present invention. Note that the photographing apparatus is not limited to a compact digital camera, and includes, for example, a mirrorless single-lens camera, a digital single-lens reflex camera, a video camera, a camcorder, a tablet terminal, a PHS (Personal Handy phone System), a smartphone, a feature phone, a portable game machine, and the like. The apparatus may be replaced with another type of apparatus having a photographing function.

[Configuration of the photographing apparatus 1]
FIG. 1 is a block diagram showing a configuration of a photographing apparatus 1 according to an embodiment of the present invention. As shown in FIG. 1, the photographing apparatus 1 includes a system controller 100, an operation unit 102, a drive circuit 104, a photographing lens 106, a diaphragm (light quantity adjustment device) 108, a shutter 110, a solid-state image sensor 112, a signal processing circuit 114, An image processing engine 116, a buffer memory 118, a card interface 120, an LCD (Liquid Crystal Display) control circuit 122, an LCD 124, and a ROM (Read Only Memory) 126 are provided. Although the photographing lens 106 has a plurality of lenses, it is shown as a single lens for convenience in FIG.

  The operation unit 102 includes various switches necessary for the user to operate the photographing apparatus 1, such as a power switch, a release switch, and a photographing mode switch. When the user operates the power switch, power is supplied from the battery (not shown) to the various circuits of the photographing apparatus 1 through the power line.

  The system controller 100 includes a CPU (Central Processing Unit) and a DSP (Digital Signal Processor). After supplying power, the system controller 100 accesses the ROM 126, reads out a control program, loads it into a work area (not shown), and executes the loaded control program to control the entire photographing apparatus 1.

  When the release switch is operated, the system controller 100 is measured by, for example, a photometric value calculated based on an image captured by the solid-state image sensor 112 or an exposure meter (not shown) built in the photographing apparatus 1. The light amount adjusting device 108 and the shutter 110 are driven and controlled via the drive circuit 104 so that appropriate exposure is obtained based on the photometric value. More specifically, the drive control of the light amount adjusting device 108 and the shutter 110 is performed based on an AE function designated by a shooting mode switch, such as a program AE (Automatic Exposure), shutter priority AE, and aperture priority AE. Further, the system controller 100 performs AF (Autofocus) control together with AE control. An active method, a phase difference detection method, a contrast detection method, or the like is applied to the AF control. The AF mode includes a central single-point ranging mode using a single central ranging area, a multi-point ranging mode using a plurality of ranging areas, and the like. The system controller 100 controls driving of the photographing lens 106 via the driving circuit 104 based on the AF result, and adjusts the focus of the photographing lens 106. Since the configuration and control of this type of AE and AF are well known, detailed description thereof is omitted here.

  The light flux from the subject passes through the photographing lens 106, the light amount adjustment device 108, and the shutter 110 and is received by the light receiving surface of the solid-state image sensor 112. The solid-state imaging device 112 is a single-plate color CCD (Charge Coupled Device) image sensor having a Bayer pixel arrangement. The solid-state imaging device 112 accumulates an optical image formed by each pixel on the light receiving surface as a charge corresponding to the amount of light, and generates R (Red), G (Green), and B (Blue) image signals. Output. The solid-state image sensor 112 is not limited to a CCD image sensor, and may be replaced with a CMOS (Complementary Metal Oxide Semiconductor) image sensor or other types of imaging devices. The solid-state image sensor 112 may also have a complementary color filter mounted thereon.

  The signal processing circuit 114 performs predetermined signal processing such as clamping and demosaicing on the image signal input from the solid-state imaging device 112 and outputs the processed signal to the image processing engine 116. The image processing engine 116 performs predetermined signal processing such as matrix operation, Y / C separation, and white balance on the image signal input from the signal processing circuit 114 to generate a luminance signal Y and color difference signals Cb and Cr. , And compressed in a predetermined format such as JPEG (Joint Photographic Experts Group). The buffer memory 118 is used as a temporary storage location for processing data when the image processing engine 116 executes processing. Further, the storage format of the captured image is not limited to the JPEG format, and may be a RAW format in which only minimal image processing (for example, black level correction) is performed.

  A memory card 200 is detachably inserted into a card slot of the card interface 120.

  The image processing engine 116 can communicate with the memory card 200 via the card interface 120. The image processing engine 116 stores the generated compressed image signal (captured image data) in the memory card 200 (or a built-in memory (not shown) provided in the image capturing apparatus 1).

  Further, the image processing engine 116 buffers the generated luminance signal Y and color difference signals Cb and Cr in a frame memory (not shown) in units of frames. The image processing engine 116 sweeps the buffered signal from each frame memory at a predetermined timing, converts it into a video signal of a predetermined format, and outputs it to the LCD control circuit 122. The LCD control circuit 122 modulates and controls the liquid crystal based on the image signal input from the image processing engine 116. Thereby, the photographed image of the subject is displayed on the display screen of the LCD 124. The user can view a real-time through image (live view) photographed with appropriate exposure and focus based on the AE control and AF control through the display screen of the LCD 124.

  When the user performs a reproduction operation of the photographed image, the image processing engine 116 reads the photographed image data designated by the operation from the memory card 200 or the built-in memory, converts it into an image signal of a predetermined format, and the LCD control circuit 122. Output to. The LCD control circuit 122 performs modulation control on the liquid crystal based on the image signal input from the image processing engine 116, so that a captured image of the subject is displayed on the display screen of the LCD 124.

  FIG. 2 is an exploded perspective view showing the configuration of the light amount adjusting device (aperture) 108. As shown in FIG. 2, the light amount adjusting device 108 includes a base member 1081 and a cam plate 1082. The base member 1081 and the cam plate 1082 have center openings 1081A and 1082A with the optical axis of the photographing lens 106 as the center. Among these central openings, the smallest central opening (for example, the central opening 1082A of the cam plate 1082) defines the fully open state (opening diameter when fully opened) of the light amount adjusting device 108. The light amount adjusting device 108 controls the F value of the photographing apparatus 1 by reducing the opening diameter of the central opening (aperture opening).

  Hereinafter, for convenience of explanation, the central axis of the central aperture that coincides with the optical axis of the photographing lens 106 is referred to as an “aperture axis”. Further, the direction of the opening axis (optical axis) is defined as the “light passing direction” in which the light incident from the photographing lens 106 passes through the aperture opening of the light amount adjusting device 108.

  Between the base member 1081 and the cam plate 1082, a plurality of (seven in this embodiment) light quantity adjusting blades 1083 are arranged. These light quantity adjusting blades 1083 are arranged in an annular shape around the central opening 1081A (and 1082A).

  FIG. 3 is a perspective view of the seven light quantity adjustment blades 1083 arranged in an annular shape. As shown in FIG. 3, the light quantity adjustment blade 1083 is a resin blade member in which a plate-like substrate portion 1083A and a plate-like blade plate portion 1083B are integrally molded. The light amount adjustment blade 1083 is arranged in a state where at least a part of the blade plate portion 1083B is overlapped with the blade plate portion 1083B of another adjacent light amount adjustment blade 1083 in the light passing direction. The substrate portion 1083A is provided with a columnar rotation shaft 1083C that is erected from the first surface 1083Aa of the substrate portion 1083A, and is cylindrical from the second surface 1083Ab opposite to the first surface 1083Aa (see FIG. 5B). An operating shaft 1083D is provided upright.

Although the base member 1081 is invisible in the drawing, seven bearing holes (for convenience, reference numerals “
1081B ". ) Are arranged at equal intervals in the circumferential direction (around the central opening 1081A of the base member 1081). A rotating shaft 1083C of each light quantity adjustment blade 1083 is inserted into each bearing hole 1081B and is rotatably supported.

  The cam plate 1082 is formed with seven cam grooves 1082B arranged at equal intervals in the circumferential direction (around the central opening 1082A of the cam plate 10082). In each cam groove 1082B, an operating shaft 1083D of each light quantity adjustment blade 1083 is inserted so as to be movable (guided) along the cam groove 1082B.

  An operating lever 1085 is attached to the cam plate 1082 by a fixing screw 1084. When the driving force of an actuator (not shown) is transmitted to the operating lever 1085, the cam plate 1082 rotates about the opening shaft. Thereby, the base member 1081 and the cam plate 1082 are relatively displaced in the rotation direction.

  When the base member 1081 and the cam plate 1082 are relatively displaced in the rotation direction, each light quantity adjustment blade 1083 is rotated (oscillated) about the rotation shaft 1083C that is pivotally supported by the bearing hole 1081B. The angular velocity (phase) of the light amount adjusting blade 1083 around the rotation shaft 1083C is controlled by the operation shaft 1083D being guided in the cam groove 1082B. Each cam groove 1082B has the same cam shape. Therefore, each light quantity adjustment blade 1083 is rotated at a synchronized angular velocity (phase).

  Each light quantity adjusting blade 1083 moves in synchronization with each other toward the opening axis when the operating shaft 1083D is guided in a direction approaching the opening axis in the cam groove 1082B in a plane orthogonal to the opening axis. Reduce the opening area.

  Further, when the operation shaft 1083D is guided in a direction away from the opening shaft in the cam groove 1082B in a plane orthogonal to the opening axis, the respective light quantity adjusting blades 1083 are moved in synchronization with each other in the direction away from the opening shaft. Widen the opening area of the central opening.

  In other words, each light quantity adjustment blade 1083 changes the amount (area) of shielding the central opening by guiding the operating shaft 1083D in the cam groove 1082B in a plane orthogonal to the opening axis. This changes the amount of light passing through the central opening.

  The blade plate portion 1083B of each light quantity adjustment blade 1083 has a shape in which the edge 1083Ba on the opening shaft side draws a gentle curve. When the operating shaft 1083D is guided in the cam groove 1082B and moved in synchronism with each other, each light amount adjusting blade 1083 defines an aperture shape close to a circle by the edge 1083Ba. Therefore, in this embodiment, “reducing the opening area of the central opening” and “increasing the opening area of the central opening” are substantially “reducing the opening diameter of the central opening” and “expanding the opening diameter of the central opening”, respectively. Are synonymous. In the following description, for convenience of explanation, the edge 1083Ba is referred to as “aperture opening defining edge 1083Ba”.

  4A shows the minimum opening diameter by the light amount adjusting blade 1083, and FIG. 4B shows the fully opened state by the light amount adjusting blade 1083. FIG. The central opening is narrowed down to the minimum opening diameter by guiding the operating shaft 1083D of each light quantity adjusting blade 1083 in a direction approaching the opening shaft in the cam groove 1082B in a plane orthogonal to the opening shaft (FIG. 4 (a)). )reference). Further, the central opening is fully opened when the operating shaft 1083D of each light quantity adjusting blade 1083 is guided to the position farthest from the opening shaft by the cam groove 1082B (see FIG. 4B).

  FIG. 5A shows a plan view of one light quantity adjustment blade 1083, and FIG. 5B shows a side view of the light quantity adjustment blade 1083 viewed from the direction of arrow A in FIG. 5A. For convenience of explanation, the plate thickness direction of the substrate portion 1083A is referred to as “plate thickness direction T”. The plate thickness direction T coincides with the light passing direction when the light amount adjusting blade 1083 is attached between the base member 1081 and the cam plate 1082.

  As shown in FIG. 5B, the blade plate portion 1083B is formed thinner than the substrate portion 1083A. By reducing the weight by forming the blade plate portion 1083B thin, the driving force required for the actuator is reduced.

  Further, as shown in FIG. 5B, the blade plate portion 1083B is formed to be inclined with respect to the substrate portion 1083A. In FIG. 5B, the angle θ is an angle formed by the substrate portion 1083A and the blade plate portion 1083B.

  In this manner, by inclining the blade plate portion 1083B by the angle θ with respect to the substrate portion 1083A, the blade plate portion 1083B is formed in parallel with the substrate portion 1083A (without being inclined with respect to the substrate portion 1083A). The projected area of the blade plate portion 1083B on the surface orthogonal to the light passing direction, that is, the surface parallel to the substrate portion 1083A is reduced. Since the area of the blade plate portion 1083B in the plane parallel to the substrate portion 1083A is reduced, each of the blade portions 1083B of the light amount adjustment blade 1083B is not overlapped with the substrate portion 1083A of another adjacent light amount adjustment blade 1083A. It becomes easy to arrange the light quantity adjusting blades 1083 side by side.

  In this embodiment, the board portion 1083A and the blade plate portion 1083B do not overlap each other, and the blade plate portions 1083B designed to be thin overlap each other. Therefore, the clearance between the base member 1081 and the cam plate 1082 necessary for arranging the light quantity adjusting blade 1083 can be suppressed. By suppressing the clearance, the thickness of the light amount adjusting device 108 in the light passing direction can be suppressed.

  Further, as shown in FIG. 5 (b), the blade plate portion 1083B has a base end 1083Bb located substantially at the same position as the surface including the first surface 1083Aa of the substrate portion 1083A in the plate thickness direction T. The tip 1083Bc is located at substantially the same position as the surface including the second surface 1083Ab. More specifically, in the plate thickness direction T, the blade plate portion 1083B has a base end 1083Bb that does not protrude from the surface including the first surface 1083Aa toward the rotating shaft 1083C, and a tip 1083Bc that includes the second surface 1083Ab. It does not protrude from the surface toward the operating shaft 1083D. That is, in the plate thickness direction T, the blade plate portion 1083B has a dimension that fits between the surface including the first surface 1083Aa and the surface including the second surface 1083Ab.

  As described above, the light amount adjustment blade 1083 is formed in parallel with the substrate portion 1083A (without inclining the substrate portion 1083A) even though the blade plate portion 1083B is inclined. Even if compared with the case where it did, the dimension of the plate | board thickness direction T is not large.

  The above is the description of the exemplary embodiments of the present invention. Embodiments of the present invention are not limited to those described above, and various modifications are possible within the scope of the technical idea of the present invention. For example, the embodiment of the present application also includes an embodiment that is exemplarily specified in the specification or a combination of obvious embodiments and the like as appropriate.

  The diaphragm (light quantity adjusting device) 108 is provided in the photographing apparatus 1 in the above embodiment, but in another embodiment, the structure is provided in an optical device (for example, an interchangeable lens barrel). It is good. That is, an optical apparatus including the diaphragm (light quantity adjusting device) 108 is also within the scope of the present invention. In this case, the driving force for the diaphragm 108 is supplied from, for example, a camera body or a motor provided in the optical device.

  In the above embodiment, the blade plate portion 1083B is formed in a flat plate shape in order to reduce the mold cost by the ease of design and the simplification of the shape. In another embodiment, the blade plate portion 1083B may be formed in a non-planar shape (for example, a shape having a curved surface) in accordance with the degree of overlap with the adjacent blade plate portion 1083 in order to improve operational stability and the like. Good.

  Further, the blade plate portion 1083 may be formed in parallel with the substrate portion 1083A only in the vicinity of the aperture opening defining edge 1083Ba. As a result, the aperture opening is neatly arranged, a diaphragm aperture having a good appearance is obtained, and a beautifully shaped blur is obtained.

DESCRIPTION OF SYMBOLS 1 Image pick-up apparatus 100 System controller 102 Operation part 104 Drive circuit 106 Shooting lens 108 Aperture 110 Shutter 112 Solid-state image sensor 114 Signal processing circuit 116 Image processing engine 118 Buffer memory 120 Card interface 122 LCD control circuit 124 LCD
126 ROM
200 Memory card 1081 Base member 1081A Center opening 1082 Cam plate 1082A Center opening 1082B Cam groove 1083 Light quantity adjusting blade 1083A Substrate portion 1083Aa First surface 1083Ab (of substrate portion) Second surface 1083B Blade plate portion 1083Ba Aperture opening Specified edge 1083Bb Base end 1083Bc (of the slat) 1083C Tip (of the slat) Rotating shaft 1083D Actuating shaft 1084 Fixing screw 1085 Actuating lever

Claims (8)

A plurality of light quantity adjustment blades having a plate-like substrate portion on which a rotation shaft and an operation shaft are erected, and a plate-like blade plate portion formed integrally with the substrate portion;
A first member having a predetermined center opening and rotatably supporting each rotation shaft of the plurality of light quantity adjustment blades arranged in a ring around the center opening;
By moving the operation axes of the plurality of light quantity adjustment blades, rotating the light quantity adjustment blades around the rotation axes, and changing the shielding amount of the central opening by the plurality of light quantity adjustment blades, A second member that changes the amount of light passing through the central aperture;
With
The light quantity adjusting blade is
It is arranged in a state where at least a part of the blade plate portion is overlapped with the blade plate portion of another light quantity adjustment blade adjacent to the blade plate portion in the light passing direction,
The vane portion is
At least, it is formed to be inclined with respect to the substrate portion at a portion overlapping the blade plate portion of the other light quantity adjustment blade,
Light quantity adjustment device. The vane portion is
The plate thickness is thinner than the substrate part,
The light quantity adjusting device according to claim 1. The vane portion is
In the plate thickness direction of the substrate portion, it has a shape that does not protrude from the surface including the first surface of the substrate portion and does not protrude from the surface including the second surface opposite to the first surface.
The light quantity adjusting device according to claim 2. The vane portion is
In the plate thickness direction of the substrate portion, the base end of the blade plate portion is positioned substantially at the same position as the surface including the first surface, and the tip end of the blade plate portion is positioned approximately at the same position as the surface including the second surface. Located in the
The light quantity adjusting device according to claim 3. The vane portion is
It is formed in a flat or non-planar shape,
The light quantity adjusting device according to any one of claims 1 to 4. The vane portion is
At least an edge portion on the opening axis side that defines the aperture opening is formed in parallel with the substrate portion,
The light quantity adjusting device according to any one of claims 1 to 4. The light quantity adjusting device according to any one of claims 1 to 6, comprising:
Shooting device. The light quantity adjusting device according to any one of claims 1 to 6, comprising:
Optical equipment.

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