JP7635681B2 - Lens barrel and imaging device - Google Patents

Description

Related to lens barrels and imaging devices.

There is known a lens barrel in which some of the multiple lens groups are insertable and detachable from the optical axis (see, for example, Patent Document 1). In such a lens barrel, it is desirable to suppress noise in communication between the camera body and the main board of the lens barrel.

JP 2013-238827 A

According to a first aspect, the lens barrel comprises an optical system including a converter lens that can move between a first position and a second position to change the focal length, a communication unit that communicates with a camera body, a control unit that controls the optical system based on information received from the camera body by the communication unit, a substrate that holds the control unit, and a moving mechanism that moves the converter lens between the first position and the second position , the substrate being positioned on the image side of the converter lens , the substrate including the substrate, and a plane perpendicular to the optical axis intersecting the moving mechanism .

According to a second aspect, an imaging device includes the lens barrel.

The configuration of the embodiments described below may be modified as appropriate, and at least a portion of the configuration may be replaced with other components. Furthermore, components that are not specifically limited in their placement may be placed in any position that achieves their function, not limited to the placement disclosed in the embodiments.

FIG. 1 is a diagram showing a camera including a lens barrel and a camera body according to an embodiment. FIG. 2 is a perspective view showing the internal structure of the lens barrel with the teleconverter lens in the attached position. FIG. 3 is a perspective view showing the internal structure of the lens barrel, with the teleconverter lens in the retracted position. FIG. 4A is a plan view showing a state in which the teleconverter lens is in an attached position, and FIG. 4B is a plan view showing a state in which the teleconverter lens is in a retracted position. FIG. 5 is a diagram showing the gear portion. FIG. 6 is a diagram illustrating the main board.

The lens barrel 100 according to one embodiment will be described in detail below with reference to the drawings. In the drawings shown below, an XYZ Cartesian coordinate system is appropriately provided to facilitate explanation and understanding. In this coordinate system, the direction from the subject toward the camera body 101 side in the camera position (hereinafter referred to as the normal position) when the photographer takes a landscape image with the optical axis OA horizontal is defined as the +Z direction. In addition, the direction toward the right side as viewed from the camera body 101 side in the normal position is defined as the +X direction. In addition, the direction toward the upper side in the normal position is defined as the +Y direction. Note that the scale of the shape, length, thickness, etc. of each part shown in the embodiment does not necessarily match the actual product, and in addition, in each drawing, some elements may be omitted from the illustration in order to facilitate understanding. In addition, in the cross-sectional view, hatching of some elements may be omitted.

FIG. 1 is a diagram showing a camera 1 including a lens barrel 100 according to this embodiment and a camera body 101. Note that in this embodiment, the lens barrel 100 is detachable from the camera body 101, but this is not limited thereto, and the lens barrel 100 and the camera body 101 may be integrated.

The camera body 101 includes an image sensor IS and a control unit (not shown). The image sensor IS is composed of a photoelectric conversion element such as a CCD (Charge Coupled Device), and converts the subject image formed by the imaging optical system (the lens barrel 100 attached to the camera body 101) into an electrical signal.

The control unit includes a CPU (Central Processing Unit) and controls the overall operation of the camera 1 related to photography, including focusing drive in the camera body 101 and the attached lens barrel 100, aperture adjustment, and blur correction of captured images caused by camera shake, etc.

As shown in FIG. 1, the lens barrel 100 according to this embodiment has a photographic optical system including a focus lens group FL, an aperture device 10, a motion compensation device 20, a movable part 300 (teleconverter lens 30), and other lens groups arranged along an optical axis OA.

In addition, the rear end of the lens barrel 100 according to this embodiment is provided with a lens mount LM that allows the lens barrel 100 to be attached to and detached from the camera body 101. In addition, the rear end of the lens barrel 100 is provided with electronic contacts CP for communicating with a control unit (not shown) arranged within the camera body 101 via electronic contacts provided on the camera body 101.

The electronic contacts CP are connected to the main board 40 of the lens barrel 100 by a flexible printed circuit board FPC. The main board 40 is equipped with a control unit 50.

The control unit 50 controls the photographing optical system. More specifically, the control unit 50 controls the focus lens group FL, the aperture device 10, and the image stabilization device 20 based on information received from a control unit (not shown) of the camera body 101 via the electronic contacts CP and the flexible printed circuit board FPC.

The lens barrel 100 also includes an outer tube 201 and an inner tube 202 that is provided on the inner periphery of the outer tube 201. The inner tube 202 movably supports the movable part 300.

The movable part 300 includes a teleconverter lens 30 and a lens holding frame 31. The teleconverter lens 30 is a lens group that moves between an attached position and a retracted position to change the focal length. The attached position is the position of the teleconverter lens 30 when the center (optical axis) of the teleconverter lens 30 is located on the optical axis OA of the other lens groups. When the teleconverter lens 30 is in the attached position, the composite focal length is increased, and a photograph can be taken in which the subject is enlarged even more than when the teleconverter lens 30 is in the retracted position. The retracted position is a position in which the teleconverter lens 30 is out of the optical path of the photographing optical system so as not to interfere with the optical path of the other lens groups.

Figures 2 and 3 are perspective views showing the internal structure of the lens barrel 100, with Figure 2 showing the teleconverter lens 30 in the attached position and Figure 3 showing the teleconverter lens 30 in the retracted position. Also, Figure 4(A) is a plan view showing the teleconverter lens 30 in the attached position, and Figure 4(B) is a plan view showing the teleconverter lens 30 in the retracted position.

The lens holding frame 31 includes a cylinder portion 31a that surrounds the outer circumference of the teleconverter lens 30, an arm portion 31b that protrudes outward from the cylinder portion 31a, and a restricting portion 31c that protrudes outward from the cylinder portion 31a (see Figs. 4(A) and 4(B)). One end of the arm portion 31b is connected to the cylinder portion 31a, and the other end of the arm portion 31b is connected to a rotation axis A4 of a fourth gear 64 provided in the gear portion 60 described later.

The movable part 300 (teleconverter lens 30) is driven between the attached position and the retracted position by a moving mechanism 600 that includes an operating lever 66 and a gear part 60.

Figure 5 is a diagram showing the gear unit 60. As shown in Figure 5, the gear unit 60 includes a first gear 61, a second gear 62, a third gear 63, a fourth gear 64, and a fifth gear 65. As described above, the rotation axis A4 of the fourth gear 64 is connected to the arm portion 31b of the lens holding frame 31. The gear unit 60 is attached to the inner cylinder 202.

2 and 3, the operating lever 66 is disposed closer to the image side than the teleconverter lens 30. The operating lever 66 is, for example, L-shaped and includes a rotating part 66a extending in an in-plane direction perpendicular to the optical axis OA (radial direction centered on the rotation axis A1 of the first gear 61) and an extending part 66b extending in the direction of the optical axis OA from one end of the rotating part 66a. The other end of the rotating part 66a is connected to the rotation axis A1 of the first gear 61 included in the gear unit 60 (see FIG. 5). This allows the operating lever 66 to rotate around the rotation axis A1.

When the photographer moves the operating lever 66 from the position shown in FIG. 2 to the position shown in FIG. 3 (raising the operating lever 66), the first gear 61 connected to the other end of the rotating part 66a rotates, and the fourth gear 64 rotates via the second gear 62 and the third gear 63. The rotation of the fourth gear 64 causes the arm part 31b of the lens holding frame 31 to rotate about the rotation axis A4, and the movable part 300 (teleconverter lens 30) moves from the mounted position to the retracted position. Similarly, when the operator moves the operating lever 66 from the position shown in FIG. 3 to the position shown in FIG. 2 (lowering the operating lever 66), the movable part 300 (teleconverter lens 30) moves from the retracted position to the mounted position.

As shown in Figs. 4A and 4B, the lens barrel 100 includes a biasing member 70. One end of the biasing member 70 is attached to the first mounting portion 31d provided near one end of the arm portion 31b, and the other end is attached to the second mounting portion 203 provided on the inner tube 202. The biasing member 70 is, for example, a tension spring that biases the first mounting portion 31d and the second mounting portion 203 to attract each other. Note that the biasing member 70 is not limited to a tension spring, and may be any other elastic member such as rubber as long as it biases the first mounting portion 31d and the second mounting portion 203 to attract each other and is deformable.

When the arm portion 31b rotates around the rotation axis A4 of the fourth gear 64, the biasing member 70 rotates around one end attached to the second attachment portion 203, and the other end attached to the first attachment portion 31d.

As shown in FIG. 4A, when the movable part 300 (teleconverter lens 30) is in the mounting position, the biasing member 70 attached to the first mounting part 31d and the second mounting part 203 is located on the mounting position side with respect to the rotation axis A4. As a result, the biasing force of the biasing member 70 applies a counterclockwise force (opposite the direction toward the retracted position, toward the mounting position) centered on the rotation axis A4 to the movable part 300 (teleconverter lens 30).

For this reason, a first limiting portion 202a is provided on the inner cylinder 202 to limit counterclockwise movement around the rotation axis A4 beyond the mounting position of the movable portion 300 (teleconverter lens 30). The first limiting portion 202a comes into contact with the regulating portion 31c of the lens holding frame 31 when the movable portion 300 (teleconverter lens 30) reaches the mounting position. This prevents the movable portion 300 (teleconverter lens 30) from rotating counterclockwise beyond the mounting position.

As shown in FIG. 4B, when the movable part 300 (teleconverter lens 30) is in the retracted position, the biasing member 70 attached to the first attachment part 31d and the second attachment part 203 is located on the retracted position side with respect to the rotation axis A4. As a result, the biasing force of the biasing member 70 applies a force to the movable part 300 (teleconverter lens 30) in a clockwise direction (the direction opposite to the direction toward the mounting position, the direction toward the retracted position) about the rotation axis A4.

For this reason, a second limiting portion 202b is provided on the inner cylinder 202 to limit clockwise movement of the movable portion 300 (teleconverter lens 30) beyond the retracted position. When the movable portion 300 (teleconverter lens 30) reaches the retracted position, the second limiting portion 202b abuts against the regulating portion 31c of the lens holding frame 31. This prevents the movable portion 300 (teleconverter lens 30) from rotating clockwise beyond the retracted position.

A main board 40 carrying a control unit 50 is fixed to the image side end of the inner cylinder 202, which movably supports the movable unit 300 (see Figure 1).

Here, if the distance in the direction of the optical axis OA from the main board to the camera body or the distance in the direction of the optical axis OA from the main board to the electronic contacts becomes long, the length of the flexible printed circuit board FPC routed in the direction of the optical axis becomes long, causing noise to occur in, for example, control signals in communication between the main board and the camera body. Therefore, in this embodiment, in the lens barrel 100 equipped with the movable part 300, the shape and position of the main board 40 are devised to suppress noise in communication between the main board 40 and the camera body 101.

FIG. 6 is a plan view for explaining the main board 40. As shown in FIG. 6, the main board 40 has a C-shape having a first end 41 and a second end 42 that are spaced apart from each other in the circumferential direction of a circle centered on the optical axis OA. A moving mechanism 600 including an operating lever 66 and a gear unit 60 is disposed between the first end 41 and the second end 42 in the circumferential direction of a circle centered on the optical axis OA. In other words, the moving mechanism 600 is disposed in the cutout portion (between the first end 41 and the second end 42) of the C-shaped main board 40. In addition, a plane including the main board 40 and perpendicular to the optical axis OA intersects with the moving mechanism 600. In other words, the main board 40 and the moving mechanism 600 overlap in the radial direction. That is, the main board 40 and the moving mechanism 600 are not stacked in the optical axis OA direction.

If the main board 40 is O-shaped and does not have the first end 41 and the second end 42, the main board 40 cannot be placed in a plane intersecting with the moving mechanism 600, so the main board 40 must be placed closer to the subject than the movable part 300 (teleconverter lens 30). In that case, the distance in the optical axis direction from the main board 40 to the camera body or the electronic contact CP becomes longer, and the length of the flexible printed circuit board FPC in the optical axis direction becomes longer, which causes noise in, for example, control signals in the communication between the main board and the camera body. On the other hand, by making the main board 40 C-shaped, the main board 40 can be placed in a plane intersecting with the moving mechanism 600, so the main board 40 can be placed closer to the image side than the movable part 300 (teleconverter lens 30). This shortens the distance in the optical axis OA direction from the main board 40 to the electronic contact CP. Therefore, the length of the flexible printed circuit board FPC and the conductors connecting the main board 40 to the electronic contact CP can be shortened. More specifically, the length T1 of the flexible printed circuit board FPC in the optical axis OA direction (the length in the optical axis OA direction from the main board 40 to the electronic contact CP) is shorter than the length T2 in the optical axis OA direction from the lens surface LS of the teleconverter lens 30 closest to the image side to the electronic contact CP (see FIG. 1). This makes it possible to suppress noise from being introduced into the signal passing through the flexible printed circuit board FPC.

As described above in detail, according to this embodiment, the lens barrel 100 includes a photographic optical system including a teleconverter lens 30 that can move between an attached position and a retracted position to change the focal length, electronic contacts CP that communicate with the camera body 101, a control unit 50 that controls the photographic optical system based on information received from the camera body 101 by the electronic contacts CP, and a main board 40 that holds the control unit 50, and the main board 40 is disposed on the image side of the teleconverter lens 30. This allows the distance from the electronic contacts CP to the main board 40 to be shortened, and the flexible printed circuit board FPC that connects the electronic contacts CP and the main board 40 can be shortened, thereby reducing noise in communication between the camera body 101 and the main board 40.

In addition, in this embodiment, the lens barrel 100 includes a moving mechanism 600 that moves the teleconverter lens 30 (movable part 300) between the mounting position and the retracted position, and includes a main board 40, and a plane perpendicular to the optical axis OA intersects with the moving mechanism 600. In other words, the main board 40 has a first end 41 and a second end 42 that are spaced apart from each other in the circumferential direction of a circle centered on the optical axis OA, and the moving mechanism 600 is disposed between the first end 41 and the second end 42. That is, the main board 40 has a C-shape. For example, when the main board 40 is O-shaped, in order to place the main board 40 closer to the image side than the teleconverter lens 30, the moving mechanism 600 and the main board 40 are stacked in the optical axis OA direction. In this case, the overall length of the lens barrel 100 becomes long. In this embodiment, because the main board 40 is C-shaped, the main board 40 and the movement mechanism 600 can be arranged on the same plane, shortening the distance from the electronic contacts CP to the main board 40 and preventing the overall length of the lens barrel 100 from becoming too long.

In addition, in this embodiment, the operating lever 66 of the moving mechanism 600 is positioned closer to the image side than the teleconverter lens 30. This improves the operability of inserting and removing the movable part 300 (teleconverter lens 30).

In the above embodiment, a teleconverter lens 30 is described, but the converter lens may be a wide converter lens.

The above-described embodiment is a preferred example. However, the present invention is not limited to this embodiment, and various modifications are possible without departing from the spirit of the present invention, and any combination of components may be used.

Reference Signs List 1 Camera 30 Teleconverter lens 40 Main board 41 First end 42 Second end 50 Control unit 60 Gear unit 66 Operation lever 100 Lens barrel 101 Camera body 600 Moving mechanism CP Electric contact FPC Flexible printed circuit board

Claims (8)

an optical system including a converter lens that is movable between a first position and a second position to change a focal length;
A communication unit that communicates with the camera body;
a control unit that controls the optical system based on information received from the camera body by the communication unit;
A substrate that holds the control unit;
a moving mechanism that moves the converter lens between the first position and the second position;
Equipped with
the substrate is disposed closer to an image than the converter lens ;
A plane including the substrate and perpendicular to the optical axis intersects with the moving mechanism.
Lens barrel. the substrate has a first end and a second end spaced apart from each other in a circumferential direction of a circle centered on the optical axis,
The moving mechanism is disposed between the first end and the second end in the circumferential direction.
The lens barrel according to claim 1 . The substrate has a C-shape.
The lens barrel according to claim 1 or 2 . The substrate and the moving mechanism are attached to the same component.
The lens barrel according to any one of claims 1 to 3 . the moving mechanism is disposed closer to the image side than the converter lens;
The lens barrel according to any one of claims 1 to 4 . A flexible printed circuit board is provided to connect the communication unit and the board.
The lens barrel according to any one of claims 1 to 5 . a length of the flexible printed circuit board in the optical axis direction is shorter than a length from a lens surface of the converter lens closest to the image side to the communication unit in the optical axis direction;
7. The lens barrel according to claim 6 . An imaging device comprising the lens barrel according to any one of claims 1 to 7 .

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