JP2007199469A - Lens unit, interchangeable lens, camera system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens unit which will not obstruct movement of a first frame member, while surely performing wiring for the first frame member capable of moving relative to a second frame member, and to provide an interchangeable lens and a camera system. <P>SOLUTION: An FPC 101 includes a first band-like part 101a connected to a movable lens frame 2, a second band-like part 101b connected to a base 51 and disposed opposite the first band-like part 101a, and a third band-like part 101c having one end formed by folding back the first band-like part 101a and the other end formed by folding back the second band-like part 101b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lens unit, an interchangeable lens, and a camera system in which a part of an optical system is movable, such as a blur correction optical system.

2. Description of the Related Art Conventionally, as this type of apparatus, an apparatus such as a voice coil motor (VCM) is used to correct image blur by shifting the blur correction optical system in a plane substantially orthogonal to the optical axis. ing.
In addition, in order to detect the shift movement amount of the blur correction optical system, a sensor using a sensor such as a PSD (Position Sensitive Detector), an LED (Light Emitting Diode), or a reflective photosensor (Photo Reflector) is known.
In such a shake correction apparatus, it is necessary to perform power supply and communication to the actuator and sensor from the fixed member side to the moving shake correction optical system side. Conventionally, a method of directly connecting a lead wire or a lead wire has been used for electrical connection between an electrical component attached to a movable part and a fixed substrate or the like.

  However, in a wiring structure that supplies power or communicates to the moving blur correction optical system side by directly connecting the lead wire and lead wire, the lead wire and lead wire come into contact with other parts, and the blur correction optical system There is a problem that the movement is hindered, or stress concentrates on a specific portion of the conducting wire or the lead wire, and the wire breaks due to repeated movement.

Further, Patent Document 1 proposes a configuration in which wiring is performed by folding a flexible printed wiring board (FPC).
However, the configuration described in Patent Document 1 has a problem in that the movement of the blur correction optical system is hindered when the folded portion comes into contact with another component.
JP 2000-321611 A

  An object of the present invention is to provide a lens unit, an interchangeable lens, and a camera that do not hinder the movement of the first frame member while reliably performing wiring to the first frame member that is movable with respect to the second frame member. Is to provide a system.

In order to solve the above-mentioned problem, the invention of claim 1 includes a first frame member that holds at least a part of an optical system, a second frame member that movably supports the first frame member, A belt-like member that has flexibility and connects the first frame member and the second frame member; and the belt-like member is connected to the first frame member. A second belt-like portion connected to the second frame member and facing the first belt-like portion, one end formed by folding the first belt-like portion, and the other end of the second belt-like portion The lens unit includes a third belt-like portion formed by folding.
According to a second aspect of the present invention, in the lens unit according to the first aspect, at least one of the first belt-shaped portion, the second belt-shaped portion, and the third belt-shaped portion is an optical axis of the optical system. It is a lens unit characterized by being substantially parallel.
According to a third aspect of the present invention, in the lens unit according to the first or second aspect, the belt-like member has a “U” shape or a “C” shape.
According to a fourth aspect of the present invention, in the lens unit according to any one of the first to third aspects, the length of the first belt-shaped portion from the first frame member to the third belt-shaped portion. And the length from the one end of the third strip portion to the other end is shorter than the length of the second strip portion from the second frame member to the third strip portion. It is the lens unit characterized.
According to a fifth aspect of the present invention, in the lens unit according to any one of the first to fourth aspects, the first frame member moves along a plane substantially perpendicular to the optical axis of the optical system. This is a lens unit.
According to a sixth aspect of the present invention, in the lens unit according to any one of the first to fifth aspects, the first frame member causes a blur of an image formed by the optical system to move. A lens unit that holds a blur correction lens to be corrected.
According to a seventh aspect of the present invention, in the lens unit according to any one of the first to sixth aspects, the band-shaped member electrically connects the first frame member and the second frame member. The lens unit is a wiring member to be connected.
According to an eighth aspect of the present invention, in the lens unit according to the seventh aspect, the wiring member is provided on the first frame member and detects a position of the first frame member and the first unit. The lens unit is connected to at least one of an actuator that drives the frame member.
A ninth aspect of the invention includes the lens unit according to any one of the first to eighth aspects, and a mount portion for attaching the lens unit to a camera that captures an image formed by the optical system. It is an interchangeable lens characterized by.
The invention of claim 10 is a camera system including the lens unit according to any one of claims 1 to 8.

  According to the present invention, since the wiring member has the first to third belt-shaped portions, wiring to the second frame member can be performed without hindering the movement of the second frame member.

  The purpose of reliably performing wiring to the first frame member without hindering the movement of the first frame member is to the first belt-like portion connected to the first frame member and the second frame member. A second belt-like portion connected and opposed to the first belt-like portion; and a third belt-like portion formed at one end by folding the first belt-like portion and at the other end by folding the second belt-like portion. This is realized by connecting the first frame member and the second frame member with the belt-shaped member.

FIG. 1 is a diagram for explaining the outline of the camera system of the present embodiment.
The camera system of this embodiment includes an interchangeable lens 100 and a camera body 200 to which the interchangeable lens 100 can be attached and detached.
The interchangeable lens 100 includes shake detection sensors AV1 and AV2, shake correction lenses 1, shake correction actuators V1 and V2, lens position detection sensors S1 and S2, a movable lens frame 2, a mount portion 19, and the like. Note that the blur correction lens 1, the blur correction actuators V1 and V2, the lens position detection sensors S1 and S2, and the movable lens frame 2 constitute a blur correction lens unit. The interchangeable lens 100 is detachably attached to the camera body 200 by the mount unit 19.
The camera body 200 has an imaging unit (not shown) in addition to the release switch 201.

  The shake detection sensors AV1 and AV2 are shake detection units formed by angular velocity sensors such as gyro sensors. The shake detection sensors AV1 and AV2 detect angular velocities around two detection axes (X axis and Y axis) orthogonal to each other in a plane substantially perpendicular to the optical axis Z of the shake correction lens 1. When the switch 200 is operated, the acceleration components in each of these two directions are output. The shake around the Y axis is called yawing, the shake around the X axis is called pitching, and the blur correction operation usually corrects the image blur caused by the shake in the two directions. Is done.

The blur correction lens 1 forms a part of the photographing optical system, and with respect to a photographing unit (not shown) (imaging element, film, etc.) disposed on the focal plane of the photographing optical system in a plane substantially orthogonal to the optical axis Z. Thus, the blur correction lens corrects the image blur in the photographing unit by moving in a direction to cancel the image blur of the subject image caused by the shake caused by the camera shake of the photographer.
The movable lens frame 2 is a first frame member that holds the shake correction lens 1 in a movable state. The shake correction lens 1 is assembled to the movable lens frame 2 to form a movable lens unit that can move in a plane substantially orthogonal to the optical axis.
The shake correction actuators V1 and V2 are drive units that generate drive force for moving the shake correction lens 1 and the movable lens frame 2, and are arranged separately for driving in the X-axis direction and driving in the Y-axis direction. In this embodiment, voice coil motors are used for the blur correction actuators V1 and V2.

The lens position detection sensors S1 and S2 are position sensors that detect the positions of the blur correction lens 1 and the movable lens frame 2, and are arranged separately for position detection in the X-axis direction and position detection in the Y-axis direction. .
In the shake correction operation, the drive direction and drive amount of the shake correction lens 1 are calculated by a calculation unit (not shown) based on the detection results of shake by the shake detection sensors AV1 and AV2, and the shake correction actuators V1 and V2 are calculated according to the calculation results. The image blur correction lens 1 is driven and controlled using the lens position detection sensors S1 and S2 to correct image blur.

FIG. 2 is a diagram of the blur correction lens unit of this embodiment as viewed from the subject side.
FIG. 3 is a cross-sectional view of the blur correction lens unit of the present embodiment cut along the blur correction actuator V2 and the spring 83.
FIG. 4 is a cross-sectional view of the blur correction lens unit of the present embodiment cut in the vicinity of the flexible printed wiring board 101 and the lens position detection sensor S1.
The cross-sectional views shown in FIG. 3 and FIG. 4 are conceptual diagrams schematically shown for explanation, and in order to facilitate understanding, the reference numerals of parts having similar forms and functions are also shown. ing.

The movable lens frame 2 is driven in the X direction and the Y direction by the blur correction actuators V1 and V2. Two coils 11 and 16 are fixed to the movable lens frame 2.
As shown in FIG. 3, the blur correction actuator V <b> 2 is a voice coil motor including a front yoke 12, a magnet 13, a coil 11, and a rear yoke 15. The front yoke 12 is fixed to the front base member 3, and the front magnet 13 is fixed on the front yoke 12. The rear yoke 15 is fixed to the rear base member 4. The coil 11 is disposed between the front magnet 13 and the rear yoke 15.
Therefore, when a current is passed through the coil 11, the coil 11 receives a force in the Y direction and drives the blur correction lens 1.
The blur correction actuator V1 is a voice coil motor that includes a front yoke 17, a magnet 18, a coil 16, and a rear yoke 20 in the same manner as the blur correction actuator V2.
Therefore, when a current is passed through the coil 16, the coil 16 receives a force in the X direction and drives the blur correction lens 1.

As shown in FIGS. 2 and 4, lens position detection sensors S1 and S2 for detecting the position of the blur correction lens 1 are provided by slit portions 2f and 2g provided on the movable lens frame 2, LEDs 21 and 22, and PSDs 23 and 24, respectively. It is configured. The LEDs 21 and 22 are fixed to the movable lens frame 2. The PSDs 23 and 24 are attached to the substrate 51, and the substrate 51 is fixed to the front base member 3.
The light emitted from the LEDs 21 and 22 passes through the slit portions 2f and 2g and reaches the PSDs 23 and 24. Accordingly, the position of the light reaching the PSDs 23 and 24 is moved according to the position where the blur correction lens 1 is moved, and the output signals of the PSDs 23 and 24 are changed. With this signal, the position of the blur correction lens 1 in the Y and X directions can be detected.

As shown in FIGS. 2 and 3, the support structure for supporting the shake correction lens 1 and the movable lens frame 2 includes sliding receiving members 71, 72, 73, sliding pieces 76, 77, 78, and springs 81, 82. , 83. The sliding receiving members 71 to 73 are fixed sliding members that are fixed to the front base member 3. The sliding pieces 76 to 78 are movable sliding members fixed at positions facing the sliding receiving members 71 to 73 of the movable lens frame 2. The sliding receiving materials 71 to 73 and the sliding pieces 76 to 78 are in contact with each other to form a sliding portion. The spring hook portions at one ends of the springs 81 to 83 are respectively engaged with the spring hook portions 2a, 2b, and 2c of the movable lens frame 2. The spring hook portions at the other ends of the springs 81 to 83 are respectively engaged with the spring hook portions 3a, 3b, 3c of the front base member 3.
Accordingly, the movable lens frame 2 is held by the front base member 3 without floating in the direction of the optical axis Z in a state where the movable lens frame 2 can move smoothly with a low load.

As shown in FIG. 3, the front base member 3 includes an engaging portion 3 h for the rear base member 4. Similarly, the rear base member 4 includes an engaging portion 4 h for the front base member 3. The front base member 3 is engaged with the engagement portion 3 h of the engagement portion 4 h of the rear base member 4 and is fixed in the thrust direction by fixing screws 45, 46 and 47.
In a state where the rear base member 4 is engaged with the front base member 3, the drive mechanism that drives the blur correction lens 1 and the movable lens frame 2 described above is in a state of being casing by the front base member 3 and the rear base member 4. It becomes. The second frame member is formed by the front base member 3, the rear base member 4, the substrate 51, and the like.

As shown in FIGS. 2 and 4, the coils 11 and 16 and the LEDs 21 and 22 fixed to the movable lens frame 2 and the substrate 51 fixed to the base member 3 are electrically connected to each other. A flexible printed wiring board (FPC) 101 is used as the belt-shaped member.
The FPC 101 includes a first belt-like portion 101a connected to the movable lens frame 2 by a movable-side attachment portion 101d, and a second belt-like portion that is connected to the substrate 51 by a fixed-side attachment portion 101e and faces the first belt-like portion 101a. 101b, and a third strip 101c having one end formed by the folded portion 101f of the first strip 101a and the other end formed by the folded portion 101g of the second strip 101b.

The first belt-like portion 101a, the second belt-like portion 101b, and the third belt-like portion 101c of the present embodiment are all provided so that their plane portions are substantially parallel to the optical axis Z. Thus, when viewed from the direction of the optical axis Z, it has a “U” shape. Therefore, the bending angle of the folded portion 101f and the folded portion 101g is approximately 90 °. By arranging the first belt-like portion 101a, the second belt-like portion 101b, and the third belt-like portion 101c in this way, the length of the FPC 101 can be increased, and the movable lens frame 2 is formed by elastic deformation of the FPC 101. The drag that is applied can be reduced.
Further, the length from the folded portion 101f to the folded portion 101g of the third belt-like portion 101c is the same as the length of the first belt-like portion 101a from the movable lens frame 2 to the third belt-like portion 101c and the length from the substrate 51 to the third. It is shorter than any of the lengths of the second belt-like portion 101b up to the belt-like portion 101c. By setting the first belt-like portion 101a, the second belt-like portion 101b, and the third belt-like portion 101c to have such a length relationship, the area occupied by the FPC 101 can be minimized.

Next, the reason why the FPC 101 is arranged in the above-described form will be described.
FIG. 5 is a diagram illustrating a case where the movable lens frame 2 is closest to the FPC 101 in the shake correction lens unit of the present embodiment.
When the movable lens frame 2 moves to the position shown in FIG. 5, the folded portions 101f and 101g may come into contact with the movable lens frame 2. However, since the bent angles of the folded portions 101f and 101g are not acute angles, the movable lens frame The movement of 2 is not greatly hindered.
Further, the lengths of the first belt-like portion 101a and the second belt-like portion 101b can be increased, and the influence of the deformation resistance force of the FPC 101 on the movement of the movable lens frame 2 can be reduced.

Here, in this embodiment, in order to explain the behavior when the FPC 101 and the movable lens frame 2 are in contact with each other more easily, a shake correction lens unit including the FPC 201 provided with only one folded portion is compared. Take an example.
FIG. 6 is a diagram illustrating a comparative example.
As shown in FIG. 6, in the FPC 201 provided with only one folded portion 201c, the folded portion 201c comes into contact with the movable lens frame 2 so that the movable lens frame 2 does not move, and the blur correction effect is obtained. It will be dropped.

FIG. 7 is an enlarged view of a portion where the FPC 101 of the present embodiment and the FPC 201 of the comparative example are in contact with the movable lens frame 2. FIG. 7A shows the present embodiment, and FIG. 7B shows a comparative example.
In the present embodiment shown in FIG. 7A, the drag to the movable lens frame 2 by the first strip 101a is shown as fl, and the drag to the movable lens frame 2 by the third strip 101c is shown as f2. From these relationships, the force that the FPC 101 applies to the movable lens frame 2 is a resultant force Fl of the drag forces fl and f2.
On the other hand, in the comparative example shown in FIG. 7B, the drag force of the belt-like portion 201a against the movable lens frame 2 is indicated as f3, and the drag force of the belt-like portion 201b against the movable lens frame 2 is indicated as f4. From these relationships, the force that the FPC 201 applies to the movable lens frame 2 is the resultant force F2 of the drag forces f3 and f4.

  As is apparent from FIG. 7, the resultant force Fl of this embodiment is clearly smaller than the resultant force F2 of the comparative example. As described above, the FPC 101 of the present embodiment having the third belt-like portion 101c has the movable lens frame 2 that is not the FPC 201 having no third belt-like portion 101c and having only one folded portion 201c. There is little influence on movement.

According to this embodiment, even if the movable lens frame 2 comes into contact with the FPC 101, the movement of the movable lens frame 2 is not hindered and the blur correction characteristic is not deteriorated.
In addition, since the FPC 101 is used and the first belt-like portion 101a, the second belt-like portion 101b, and the third belt-like portion 101c are provided for wiring, there is a possibility of disconnection without occupying a large space. Is a low and highly reliable blur correction lens unit.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
(1) In the present embodiment, the coils 11 and 16 and the LEDs 21 and 22 are all electrically connected to the substrate 51 using the FPC 101. However, the present invention is not limited to this example. Only 16 or only the LEDs 21 and 22 may be wired by FPC, or only those appropriately selected from these may be wired by FPC.

(2) In the present embodiment, an example in which the coils 11 and 16 and the LEDs 21 and 22 provided on the movable lens frame 2 that holds the shake correction lens 2 and the substrate 51 are connected is shown. , PSD connection may be performed.

(3) In the present embodiment, the example in which the three belt-like portions of the first belt-like portion 101a, the second belt-like portion 101b, and the third belt-like portion 101c are formed is shown. Four folding portions are added between the first belt-like portion 101 a and the movable lens frame 2, or a folding portion is further added between the second belt-like portion 101 b and the substrate 51. You may provide above. Further, the first belt-like portion 101a, the second belt-like portion 101b, and the third belt-like portion 101c may be bent to have a C shape.

It is a figure explaining the outline | summary of the camera system of a present Example. It is the figure which looked at the blurring correction lens unit of a present Example from the to-be-photographed object side. It is sectional drawing which cut | disconnected the blurring correction lens unit of a present Example in blur correction actuator V1 and spring 83 vicinity. It is sectional drawing which cut | disconnected the blurring correction lens unit of a present Example in flexible printed wiring board 101 and lens position detection sensor S1 vicinity. FIG. 6 is a diagram illustrating a case where the movable lens frame 2 is closest to the FPC 101 in the shake correction lens unit of the present embodiment. It is a figure which shows a comparative example. FIG. 4 is an enlarged view of a portion where the FPC 101 of the present embodiment and the FPC 201 of the comparative example are in contact with the movable lens frame 2.

Explanation of symbols

2: movable lens frame, 3: front base member, 4: rear base member, 51: substrate, 101: FPC, 101a: first strip portion, 101b: second strip portion, 101c: third strip portion, 101f, 101g: folded portion

Claims (10)

A first frame member holding at least a part of the optical system;
A second frame member that movably supports the first frame member;
A band-shaped member having flexibility and connecting the first frame member and the second frame member;
With
The band-shaped member includes a first band-shaped portion connected to the first frame member, a second band-shaped portion connected to the second frame member and facing the first band-shaped portion, and one end of the band-shaped member A lens unit comprising: a third belt-like portion formed by folding the first belt-like portion and the other end formed by folding the second belt-like portion. The lens unit according to claim 1,
At least one of the first belt-like portion, the second belt-like portion, and the third belt-like portion is substantially parallel to the optical axis of the optical system. In the lens unit according to claim 1 or 2,
The lens unit, wherein the belt-like member has a “U” shape or a “C” shape. In the lens unit according to any one of claims 1 to 3,
Either the length of the first belt-like portion from the first frame member to the third belt-like portion or the length of the second belt-like portion from the second frame member to the third belt-like portion The lens unit is characterized in that a length from the one end to the other end of the third belt-like portion is shorter. In the lens unit according to any one of claims 1 to 4,
The lens unit, wherein the first frame member moves along a plane substantially orthogonal to the optical axis of the optical system. In the lens unit according to any one of claims 1 to 5,
The lens unit, wherein the first frame member holds a blur correction lens that corrects a blur of an image formed by the optical system when the first frame member moves. In the lens unit according to any one of claims 1 to 6,
The lens unit, wherein the belt-shaped member is a wiring member that electrically connects the first frame member and the second frame member. The lens unit according to claim 7, wherein
The wiring member is connected to at least one of a position detection sensor provided on the first frame member for detecting the position of the first frame member and an actuator for driving the first frame member. Characteristic lens unit. The lens unit according to any one of claims 1 to 8,
An interchangeable lens, comprising: a mount portion for attaching the lens unit to a camera that captures an image formed by the optical system. A camera system comprising the lens unit according to any one of claims 1 to 8.

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