Lens device and imaging apparatus

Abstract

To provide a small-sized lens device.SOLUTION: A lens device (100) has: first optical systems (301, 302, 306); second optical systems (401, 402, 406) that are arranged in parallel with the first optical systems; a base member (103) that holds the first optical systems and the second optical systems movably in an optical axis direction; a first driving unit (108) that moves the base member in the optical axis direction; a first holding unit (407) that holds some of a plurality of lenses constituting the second optical systems; and a second driving unit (409) that moves the first holding unit in the optical axis direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a lens device and an imaging device.

Background Art

[0002] Conventionally, interchangeable lenses for stereoscopic photography have been known. In a lens device in which two optical systems are arranged in parallel and two image circles are formed in parallel on one imaging element, in order to capture an image with a parallax, it is necessary to perform focus adjustment for each of the two optical systems. Patent Document 1 discloses a lens device having a first focus adjustment unit that simultaneously adjusts the focus of a first optical system and a second optical system, and a second focus adjustment unit that adjusts a deviation in the relative focal position between the first optical system and the second optical system. The first focus adjustment unit is connected to both the first optical system and the second optical system, and the second focus adjustment unit is connected to one of the first optical system or the second optical system.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the lens device disclosed in Patent Document 1, a lens barrel (holding unit) that holds all the lenses constituting one of the first optical system or the second optical system is connected to the second focus adjustment unit. For this reason, the driving load increases, and the second focus adjustment unit becomes larger, resulting in an increase in the size of the lens device.

[0005] Therefore, an object of the present invention is to provide a small lens device.

Means for Solving the Problems

[0006] As one aspect of the present invention, a lens device includes a first optical system, a second optical system arranged in parallel with the first optical system, a base member that holds the first optical system and the second optical system so as to be movable in the optical axis direction, a first driving unit that moves the base member in the optical axis direction, a first holding unit that holds a part of a plurality of lenses constituting the second optical system, and a second driving unit that moves the first holding unit in the optical axis direction.

[0007] Other objects and features of the present invention will be described in the following embodiments.

Advantages of the Invention

[0008] According to the present invention, a small-sized lens device can be provided.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Modes for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment

[0011] First, referring to FIGS. 1 to 4, Example 1 of the present invention will be described. FIG. 1 is a perspective view of an imaging device 10 in this example. The imaging device 10 includes a camera body 200 and a lens device (interchangeable lens) 100 that is detachable from the camera body 200. However, this example is not limited thereto, and it is also applicable to an imaging device in which the camera body and the lens device are integrally configured.

[0012] The lens device 100 is configured to be detachable from the camera body 200 via a mount (not shown). The lens device 100 has a lens unit 101, a control unit (not shown), a lens drive instruction means, and a contact portion that can communicate with the camera body 200. The camera body 200 has an imaging element 201 such as a CMOS sensor, a control unit (not shown), and a contact portion that can communicate with the lens device 100. The imaging element 201 is a single imaging element that photoelectrically converts a first optical image formed by a first optical system and a second optical image formed by a second optical system arranged in parallel with the first optical system, respectively.

[0013] FIG. 2 is an exploded perspective view of the lens unit 101 in this example. The lens unit 101 has a first optical system and a second optical system arranged in parallel with the first optical system. The first optical system has a plurality of lenses including a first lens 301, a second lens 302, and a third lens 306 in order from the object side to the image side along the direction of the first optical axis 300. Since the central axes of all the lenses constituting the first optical system are the first optical axis 300, it is a coaxial optical system. The second optical system has a plurality of lenses including a first lens 401, a second lens 402, and a third lens 406 in order from the object side to the image side along the direction of the second optical axis 400. Similar to the first optical system, the second optical system is also a coaxial optical system because the central axes of all the lenses constituting it are the second optical axis 400.

[0014] The first lens holding cylinder 102 holds the first lens 301 of the first optical system and the first lens 401 of the second optical system. The second lens holding cylinder (second holding portion) 303 holds the second lens 302 of the first optical system. The second lens holding cylinder (third holding portion) 403 holds the second lens 402 of the second optical system. That is, the second lens holding cylinder 303 holds at least some of the lenses of the first optical system, and the second lens holding cylinder 403 is arranged in parallel with the second lens holding cylinder 303 and holds at least some of the lenses of the second optical system.

[0015] The second lens holding cylinder 303 is fixed to the groove portion 102a of the first lens holding cylinder 102 and position-defined using the roller 304 and the screw 305. The roller 304 is an eccentric roller (second defining portion) that defines the position of the second lens holding cylinder 303 in an adjustable manner. Similarly, the second lens holding cylinder 403 is fixed to the first lens holding cylinder 102 and position-defined using the roller 404 and the screw 405. The roller 404 is an eccentric roller (third defining portion) that defines the position of the second lens holding cylinder 403 in an adjustable manner.

[0016] The third lens holding cylinder 307 holds the third lens 306 of the first optical system. The third lens holding cylinder (first holding portion) 407 holds the third lens 406 of the second optical system. That is, the third lens holding cylinder 407 holds a part of the plurality of lenses constituting the second optical system. The third lens holding cylinder 307 is fixed to the base member (main base) 103 using the screw 308 and position-defined.

[0017] The third lens holding cylinder 407 is an adjustment portion for adjusting the defocus difference (the deviation of the relative focal positions between the first optical system and the second optical system) between the first optical system and the second optical system.

[0018] The third lens holding cylinder 407 is movable forward and backward (movable) in the direction along the second optical axis 400 (optical axis direction) by a guide bar 408 sandwiched between the first lens holding cylinder 102 and the base member 103 and a focus difference adjustment drive unit (second drive unit) 409. In this way, the focus difference adjustment drive unit 409 moves the third lens holding cylinder 407 in the optical axis direction. The focus difference adjustment drive unit 409 is electrically connected to a fixed substrate (not shown) by a flexible substrate (not shown). The focus difference adjustment drive unit 409 drives the third lens holding cylinder 407 (only a part of all the lenses constituting the second optical system) to adjust the focus difference between the first optical system and the second optical system (the deviation of the relative focal positions of the first optical system and the second optical system) (perform focus difference adjustment). For this reason, the driving load is light and the driving actuator can be miniaturized. As a result, the lens device 100 can be miniaturized.

[0019] Since the third lens holding cylinder 307 is a fixed group, the accuracy of focus difference adjustment is higher than that in a configuration where the third lens holding cylinder 307 is a focus adjustment group similar to the third lens holding cylinder 407. The first lens holding cylinder 102 is fixed to the base member 103 with screws 104 and its position is defined. The cam follower 103a of the base member 103 is inserted into the straight groove 105a of the guide cylinder 105 and the cam groove 106a of the cam ring 106. By the rotation of the cam ring 106, the first lens holding cylinder 102 is movable forward and backward (movable) in the direction along the first optical axis 300 and the second optical axis 400 (optical axis direction). The rotation range of the cam ring 106 is restricted by screws 107.

[0020] The focus drive unit (first drive unit) 108 has a drive source 109 and a transmission unit 110, and is fixed to the guide cylinder 105 with screws (not shown). The focus drive unit 108 is also electrically connected to a fixed substrate (not shown) by a flexible substrate (not shown). The rotation of the drive source 109 rotates the cam ring 106 via the transmission unit 110, and moves the base member 103 forward and backward in the direction along the first optical axis 300 and the second optical axis 400 (optical axis direction). In this way, the focus drive unit 108 simultaneously performs focus adjustment of the first optical system and the second optical system by moving the base member 103 in the optical axis direction.

[0021] FIG. 3 is a front view of the lens unit 101 in this embodiment as viewed from directions along the first optical axis 300 and the second optical axis 400. FIG. 4 is a side view of the lens unit 101 as viewed from a direction perpendicular to each of the first optical axis 300 and the second optical axis 400 (a direction in which the first optical axis 300 and the second optical axis 400 overlap each other). FIGS. 3 and 4 respectively extract and show the second lens holding cylinder 303, the roller 304, the screw 305, the second lens holding cylinder 403, the roller 404, the screw 405, the focus difference adjustment drive unit 409, and the focus drive unit 108 from the lens unit 101.

[0022] As shown in FIG. 3, when the lens unit 101 (lens device 100) is viewed along the optical axis direction, the focus difference adjustment drive unit 409 is arranged at a position avoiding the straight line 500 connecting the first optical axis 300 and the second optical axis 400 (so as not to overlap with the straight line 500). Further, when the lens unit 101 is viewed along the optical axis direction, the focus difference adjustment drive unit 409 is arranged at a position avoiding the rollers 304 and 404 (so as not to overlap with the rollers 304 and 404, that is, at a different phase). The drive source 109 of the focus drive unit 108 is arranged so as not to overlap with the focus difference adjustment drive unit 409 when the lens unit 101 is viewed along the optical axis direction. With this arrangement, miniaturization in the radial direction of the lens device 100 is possible.

[0023] As shown in FIG. 4, when viewed from the direction in which the first optical axis 300 and the second optical axis 400 overlap each other, at least a part of the focus drive unit 108 and at least a part of the focus difference adjustment drive unit 409 are arranged so as to overlap each other at positions along the optical axis direction. Further, at least a part of the focus difference adjustment drive unit 409 and at least a part of the rollers 304 and 404 are arranged so as to overlap each other when viewed from the direction in which the first optical axis 300 and the second optical axis 400 overlap each other. With this arrangement, miniaturization in the overall length direction (optical axis direction) of the lens device 100 is possible.

Embodiment

[0024] Next, referring to FIGS. 5 and 6, Example 2 of the present invention will be described. FIG. 5 is a front view of the lens unit 101 in this example as viewed in the direction along the first optical axis 300 and the second optical axis 400. FIG. 6 is a side view of the lens unit 101 as viewed in the direction perpendicular to each of the first optical axis 300 and the second optical axis 400 (the direction in which the first optical axis 300 and the second optical axis 400 overlap each other).

[0025] As shown in FIG. 5, when the lens unit 101 (lens device 100) is viewed along the optical axis direction, the focus difference adjustment drive unit 409 is disposed at a position avoiding the straight line 500 connecting the first optical axis 300 and the second optical axis 400. Further, the focus difference adjustment drive unit 409 is disposed at a position overlapping at least a part of the rollers 304 and 404. Also, the drive source 109 of the focus drive unit 108 is disposed at a position not overlapping with the focus difference adjustment drive unit 409. With this arrangement, miniaturization in the radial direction of the lens device 100 is possible.

[0026] As shown in FIG. 6, when viewed in the direction in which the first optical axis 300 and the second optical axis 400 overlap each other, at least a part of the focus difference adjustment drive unit 409 and at least a part of the focus drive unit 108 are arranged to overlap each other at positions along the optical axis direction. With this arrangement, miniaturization in the overall length direction of the lens device 100 is possible.

Example

[0027] Next, referring to FIGS. 7 and 8, Example 3 of the present invention will be described. FIG. 7 is a front view of the lens unit 101 in this example as viewed in the direction along the first optical axis 300 and the second optical axis 400. FIG. 8 is a side view of the lens unit 101 as viewed in the direction perpendicular to each of the first optical axis 300 and the second optical axis 400 (the direction in which the first optical axis 300 and the second optical axis 400 overlap each other).

[0028] As shown in FIG. 7, when the lens unit 101 (lens device 100) is viewed along the optical axis direction, the focus difference adjustment drive unit 409 is arranged at a position avoiding the straight line 500 connecting the first optical axis 300 and the second optical axis 400. Further, when the lens unit 101 is viewed along the optical axis direction, the focus difference adjustment drive unit 409 is arranged at a position not overlapping with the rollers 304 and 404. Further, the drive source 109 of the focus drive unit 108 is arranged at a position not overlapping with the focus difference adjustment drive unit 409. With this arrangement, miniaturization in the radial direction of the lens device 100 is possible.

[0029] As shown in FIG. 8, when viewed from the direction in which the first optical axis 300 and the second optical axis 400 overlap each other, at least a part of the focus difference adjustment drive unit 409 and at least a part of the focus drive unit 108 are arranged to overlap each other at positions along the optical axis direction. When viewed from the direction in which the first optical axis 300 and the second optical axis 400 overlap each other, at least a part of the focus difference adjustment drive unit 409 and at least a part of the rollers 304 and 404 are arranged to overlap each other. With this arrangement, miniaturization in the overall length direction of the lens device 100 is possible.

[0030] The disclosure of each embodiment includes the following configurations. (Configuration 1) A first optical system, A second optical system arranged in parallel with the first optical system, A base member that movably holds the first optical system and the second optical system in the optical axis direction, A first drive unit that moves the base member in the optical axis direction, A first holding unit that holds a part of a plurality of lenses constituting the second optical system, A lens device, characterized by comprising a second drive unit that moves the first holding unit in the optical axis direction. (Configuration 2) When the lens device is viewed along the optical axis direction, the second drive unit is arranged so as not to overlap with the straight line connecting the first optical axis of the first optical system and the second optical axis of the second optical system, The lens device according to Configuration 1, wherein the first driving unit is arranged so as not to overlap with the second driving unit. (Configuration 3) In a direction perpendicular to each of the first optical axis of the first optical system and the second optical axis of the second optical system, when the lens device is viewed from a direction in which the first optical axis and the second optical axis overlap each other, at least a part of the first driving unit and at least a part of the second driving unit are arranged so as to overlap each other at positions along the optical axis direction. The lens device according to Configuration 1 or 2. (Configuration 4) The lens device according to any one of Configurations 1 to 3, wherein each of the first optical system and the second optical system is a coaxial optical system. (Configuration 5) The first driving unit has a driving source and a transmission unit. When the lens device is viewed along the optical axis direction, the driving source is arranged so as not to overlap with the second driving unit. The lens device according to any one of Configurations 1 to 4. (Configuration 6) The first driving unit simultaneously performs focus adjustment of the first optical system and the second optical system by moving the base member in the optical axis direction. The second driving unit performs defocus adjustment for adjusting a deviation in the relative focal position between the first optical system and the second optical system by moving a part of the plurality of lenses constituting the second optical system in the optical axis direction. The lens device according to any one of Configurations 1 to 5. (Configuration 7) A second holding unit that holds at least a part of the lenses of the first optical system. Further includes a third holding unit that is arranged in parallel with the second holding unit and holds at least a part of the lenses of the second optical system. The second holding unit has a second defining unit that defines a position. The lens device according to any one of Configurations 1 to 6, wherein the third holding unit has a third defining unit that defines a position. (Configuration 8) In a direction perpendicular to each of the first optical axis of the first optical system and the second optical axis of the second optical system, when the lens device is viewed from a direction in which the first optical axis and the second optical axis overlap each other, the second driving unit is arranged so as to overlap each of the second regulating unit and the third regulating unit. When the lens device is viewed along the optical axis direction, the second driving unit is arranged so as not to overlap each of the second regulating unit and the third regulating unit, according to the lens device of configuration 7. (Configuration 9) The second regulating unit regulates the position of the second holding unit so as to be adjustable. The third regulating unit regulates the position of the third holding unit so as to be adjustable, according to the lens device of configuration 7 or 8. (Configuration 10) An imaging device, comprising the lens device according to any one of configurations 1 to 9, and an imaging element. (Configuration 11) The imaging element is a single imaging element that photoelectrically converts a first optical image formed by the first optical system and a second optical image formed by the second optical system, according to the imaging device of configuration 10.

[0031] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist thereof.

Explanation of reference numerals

[0032] 100 Lens device 108 Focus driving unit (first driving unit) 301 First lens (first optical system) 302 Second lens (first optical system) 306 Third lens (first optical system) 401 First lens (second optical system) 402 Second lens (second optical system) 406 Third lens (second optical system) 407 Third lens holding cylinder (first holding unit) 409 Focus adjustment drive unit (second drive unit)

Claims

1. a first optical system, a second optical system arranged in parallel with the first optical system, a base member that holds the first optical system and the second optical system movably in the optical axis direction, a first driving unit that moves the base member in the optical axis direction, a first holding unit that holds a part of a plurality of lenses constituting the second optical system, and a second driving unit that moves the first holding unit in the optical axis direction, characterized in that the lens device has the above components.

2. When the lens device is viewed along the optical axis direction, the second driving unit is arranged so as not to overlap with a straight line connecting the first optical axis of the first optical system and the second optical axis of the second optical system, and the first driving unit is arranged so as not to overlap with the second driving unit. The lens device according to claim 1, characterized by the above arrangement.

3. In a direction perpendicular to each of the first optical axis of the first optical system and the second optical axis of the second optical system, when the lens device is viewed from a direction in which the first optical axis and the second optical axis overlap with each other, at least a part of the first driving unit and at least a part of the second driving unit are arranged so as to overlap with each other at positions along the optical axis direction. The lens device according to claim 1, characterized by the above arrangement.

4. The first optical system and the second optical system are each a coaxial optical system. The lens device according to claim 1, characterized by the above structure.

5. The first driving unit has a driving source and a transmission unit, and when the lens device is viewed along the optical axis direction, the driving source is arranged so as not to overlap with the second driving unit. The lens device according to claim 1, characterized by the above arrangement.

6. The first driving unit simultaneously performs focus adjustment of the first optical system and the second optical system by moving the base member in the optical axis direction, and the second driving unit performs defocus adjustment to adjust a deviation in the relative focal position between the first optical system and the second optical system by moving the part of the plurality of lenses constituting the second optical system in the optical axis direction. The lens device according to any one of claims 1 to 5, characterized by the above operation.

7. a second holding unit that holds at least a part of the lenses of the first optical system, and a third holding unit that is arranged in parallel with the second holding unit and holds at least a part of the lenses of the second optical system, wherein the second holding unit has a second defining unit that defines a position. The lens device according to any one of claims 1 to 5, wherein the third holding portion has a third defining portion that defines a position.

8. In a direction perpendicular to each of the first optical axis of the first optical system and the second optical axis of the second optical system, when the lens device is viewed from a direction in which the first optical axis and the second optical axis overlap each other, the second driving portion is arranged so as to overlap each of the second defining portion and the third defining portion. The lens device according to claim 7, wherein when the lens device is viewed along the optical axis direction, the second driving portion is arranged so as not to overlap each of the second defining portion and the third defining portion.

9. The second defining portion defines the position of the second holding portion so as to be adjustable. The lens device according to claim 7, wherein the third defining portion defines the position of the third holding portion so as to be adjustable.

10. An imaging device comprising the lens device according to any one of claims 1 to 5 and an imaging element.

11. The imaging device according to claim 10, wherein the imaging element is a single imaging element that photoelectrically converts a first optical image formed by the first optical system and a second optical image formed by the second optical system.

Images