Lens device

Abstract

To provide a compact lens device.SOLUTION: A lens device 10 includes: a holding frame 22 for holding a lens 20; driving mechanisms 14a, 14b, and 14c for moving the holding frame 22 along an optical axis L direction; a base member 40 provided in front of or behind the holding frame 22 in an optical axis direction; and elastic members 42a, 42b, and 42c where one ends 46a, 46b, and 46c are fixed to the base member 40, and other ends 48a, 48b, and 48c are fixed to the holding frame 22, and which regulates an angle change of the holding frame 22 according to the movement. The elastic members 42a, 42b, and 42c are provided with a distance from an optical axis L that is larger than the distance to the outer periphery of the lens 20 and within a range smaller than the distance to the outer periphery of the holding frame 22.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a lens device. [Background technology]

[0002] Patent Document 1 describes a configuration that includes a holding member that holds a lens and a zigzag-shaped elastic member that extends outward from the outer periphery of the holding member, and that supports the holding member movably by the elastic member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-076985 A Summary of the Invention

[0004] One embodiment of the disclosed technique provides a miniature lens arrangement. [Means for solving the problem]

[0005] One aspect of a lens device relating to the technology of the present disclosure includes a holding member that holds a lens, a driving mechanism that moves the holding member along the optical axis direction, a base member that is provided in front of or behind the holding member in the optical axis direction, and an elastic member having one end fixed to the base member and the other end fixed to the holding member and that regulates angular change of the holding member associated with movement, wherein the elastic member is provided within a range whose distance from the optical axis is greater than the outer periphery of the lens and smaller than the outer periphery of the holding member.

[0006] The change in angle may be a tilt of the holding member relative to the optical axis.

[0007] A plurality of elastic members may be provided around the optical axis.

[0008] The elastic members may be formed in an arc shape, and when observed in the optical axis direction, adjacent elastic members may be arranged so that at least a portion of each of the elastic members overlaps in the optical axis direction.

[0009] The elastic member may be a leaf spring.

[0010] When observed from the optical axis direction, it is preferable that the angle between a perpendicular line from one end to the optical axis and a perpendicular line from the other end to the optical axis is an integral multiple of 180°.

[0011] The angle is 360° or more. When one elastic member is observed from the optical axis direction, the one elastic member may have an overlapping region in which the elastic members overlap in the optical axis direction.

[0012] The elastic members may be three in number and provided at intervals of 120° around the optical axis.

[0013] The drive mechanism is an actuator consisting of a support member having a magnet and a coil fixed to the holding member, and the drive mechanism may be three in number, provided at 120° intervals around the optical axis, corresponding to the positions where the elastic member is fixed to the base member.

[0014] The holding member may include a locking member that locks the holding member to one end portion in the optical axis direction, and a lock-releasing member that releases the lock.

[0015] The locking member may be a resin wire, and the unlocking member may be a heater that heats and cuts the resin wire.

[0016] The actuator may further include a sensor that detects the position of the holding member or the amount of deformation of the elastic member, and a processor that controls the drive mechanism using information from the sensor. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 is an external view of the lens device. [Diagram 2]FIG. [Diagram 3] FIG. [Figure 4] FIG. 2 is an explanatory diagram showing an electrical configuration of the lens device. [Diagram 5] FIG. 4 is an explanatory diagram of a linear motion compensation mechanism. [Figure 6] FIG. [Figure 7] 5A and 5B are explanatory diagrams showing the relationship between a lens unit and an elastic member. [Figure 8] FIG. 4 is an explanatory diagram of a linear motion compensation mechanism. [Figure 9] FIG. 4 is an explanatory diagram of a linear motion compensation mechanism. [Figure 10] FIG. 4 is an explanatory diagram of a linear motion compensation mechanism. [Figure 11] 4 is an explanatory diagram of a locking member and an unlocking member. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] [First embodiment] 1, 2, and 3, a lens device 10 is mounted on a photographing device such as a digital camera, a smartphone, a video camera, etc. The lens device 10 includes a lens unit 12, drive mechanisms 14a, 14b, and 14c, sensors 16a, 16b, and 16c, and a linear motion compensation mechanism 18.

[0019] The lens unit 12 is an integrated unit of a lens 20 and a holding frame 16 (holding member) that holds the lens 20. The lens unit 12 slides along the optical axis L (in the direction of the optical axis L) together with the lens 20 during focusing and zooming.

[0020] The driving mechanisms 14a, 14b, and 14c are arranged at intervals of 120° around the optical axis L outside the lens unit 12. The driving mechanisms 14a, 14b, and 14c are actuators of the present invention, and the driving mechanism 14a includes a magnet unit 24a (support member) and a coil 26a, the driving mechanism 14b includes a magnet unit 24b (support member) and a coil 26b, and the driving mechanism 14c includes a magnet unit 24c (support member) and a coil 26c.

[0021] The magnet unit 24a is composed of a magnet and a yoke for controlling the flow of magnetic force from the magnet, and an end 28a (on the outer side) opposite the lens unit 12 is fixed to a main body (not shown) of the lens device 10. In addition, an end 30a (on the inner side) of the magnet unit 24a on the lens unit 12 side is formed into a plate shape that is long in the optical axis L direction.

[0022] The coil 26a is formed in a ring shape, and the end 30a of the magnet unit 24a is inserted through the center. The coil 26a is energized by a driver 32a (see FIG. 4) to generate a magnetic field. The coil 26a slides in the optical axis L direction along the end 30a without contacting the magnet unit 24a (end 30a) due to the interaction between the magnetic field thus generated and the magnetic field generated by the magnet unit 24a.

[0023] Similarly, magnet unit 24b is composed of a magnet and a yoke, and an outer end 28b is fixed to a main body (not shown) of lens device 10. Also, inner end 30b of magnet unit 24b is formed in a plate shape long in the optical axis L direction, and is inserted through coil 26b. Then, coil 26b is energized by driver 32b (see FIG. 4) to form a magnetic field, and the magnetic field thus formed and the magnetic field formed by magnet unit 24b act to slide in the optical axis L direction along end 30b without coming into contact with magnet unit 24b.

[0024] Furthermore, the magnet unit 24c is composed of a magnet and a yoke, and an outer end 28c is fixed to a main body (not shown) of the lens device 10. The inner end 30c of the magnet unit 24c is formed in a plate shape long in the optical axis L direction, and is inserted into the coil 26c. The coil 26c is energized by a driver 32c (see FIG. 4) to form a magnetic field, and the magnetic field thus formed and the magnetic field formed by the magnet unit 24c act to slide in the optical axis L direction along the end 30c without coming into contact with the magnet unit 24c (end 30c).

[0025] The coils 26a, 26b, and 26c described above are fixed to the outer periphery of the lens unit 12. This allows the lens unit 12 to slide in the direction of the optical axis L together with the coils 26a, 26b, and 26c.

[0026] The sensors 16a, 16b, 16c are arranged at 120° intervals around the optical axis L on the outside of the lens unit 12, similar to the driving mechanisms 14a, 14b, 14c. The sensors 16a, 16b, 16c have ends 34a, 34b, 34c (outside) opposite the lens unit 12, fixed to a main body (not shown) of the lens device 10. The sensors 16a, 16b, 16c include detection units 36a, 36b, 36c that detect the position of the outer periphery of the lens unit 12. The detection units 36a, 36b, 36c are formed long in the optical axis L direction, arranged outside the movement path of the lens unit 12 and in non-contact with the lens unit 12, and detect the position of the outer periphery of the lens unit 12 (position in the optical axis L direction). Although the above description has been given taking as an example a configuration in which the position of the lens unit 12 (holding frame 16) is detected by the sensors 16a, 16b, and 16c, a configuration in which the deformation amounts of elastic members 42a, 42b, and 42c, which will be described later, are detected may also be used.

[0027] 4, the lens device 10 is provided with a processor 38, and the drivers 32a, 32b, and 32c and the sensors 16a, 16b, and 16c are connected to the processor 38. The processor 38 is, for example, a programmable logic device (PLD) that is a processor whose circuit configuration can be changed after manufacture, such as a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), or a dedicated electric circuit that is a processor having a circuit configuration designed specifically for executing various processes.

[0028] The position (information (signal) indicating the position) of the lens unit 12 detected by the sensors 16a, 16b, 16c is input to the processor 38, and the processor 38 grasps the position and attitude (angle with respect to the optical axis L) of the lens unit 12 using the information input from each of the sensors 16a, 16b, 16c. Then, while grasping the position and attitude of the lens unit 12 as described above, the processor 38 controls the position and attitude of the lens unit 12 by controlling the supply of electricity to each of the coils 26a, 26b, 26c via the drivers 32a, 32b, 32c.

[0029] The lens device 10 of the present invention moves the lens unit 12 in a non-contact manner, without sliding between components. This results in higher durability and weather resistance than a configuration in which the movement of the lens unit involves sliding between components. That is, in a configuration in which the movement of the lens unit involves sliding between components, it is necessary to apply a lubricant or the like to the sliding parts, but if the lubricant dries out or deteriorates depending on the period of use and the environment in which it is used, there is a problem that it will no longer function normally. In contrast, the lens device 10, which does not have a sliding part, does not have the above-mentioned problems. In particular, in an environment with low atmospheric pressure, the above-mentioned problems become more pronounced, and therefore the lens device 10 of the present invention can be used suitably in such an environment.

[0030] On the other hand, in lens device 10, since there is no sliding part, the orientation of lens 20 may change as lens unit 12 moves (lens unit 12 (lens 20, holding frame 22) does not move linearly, and the optical axis of lens 20 may tilt (fall) relative to optical axis L). For this reason, lens device 10 is provided with linear motion compensation mechanism 18 to prevent lens 20 from falling as lens unit 12 moves and to ensure linear movement of lens 20.

[0031] 5, the linear motion compensation mechanism 18 includes a base member 40 and elastic members 42a, 42b, and 42c. The base member 40 is formed in a cylindrical shape (ring shape) having an opening 44 that exposes the optical axis L, and is disposed behind the lens unit 12. The rear surface of the base member 40 is fixed to a main body (not shown) of the lens device 10.

[0032] The elastic members 42a, 42b, 42c are leaf springs formed in an arc shape, and are arranged at intervals of 120° around the optical axis L. One ends 46a, 46b, 46c of the elastic members 42a, 42b, 42c are fixed to the rear surface of the lens unit 12 (holding frame 22), and the other ends 48a, 48b, 48c are fixed to the front surface of the base member 40. These elastic members 42a, 42b, 42c suppress the lens 20 from falling due to the movement of the lens unit 12, and ensure that the lens 20 moves linearly.

[0033] 6, the elastic members 42a, 42b, and 42c are provided within a range in which the distance from the optical axis L is greater than the distance to the outer periphery of the lens 20 and smaller than the distance to the outer periphery of the holding frame 22. This allows the lens device 10 to be made more compact.

[0034] In this embodiment, the drive mechanisms 14a, 14b, and 14c are arranged such that the other end 48a and the drive mechanism 14a, the other end 48b and the drive mechanism 14b, and the other end 48c and the drive mechanism 14c are arranged at corresponding angular positions (common angular positions around the optical axis L). In this embodiment, the sensors 16a, 16b, and 16c are arranged such that the one end 46a and the sensor 16a, the one end 46b and the sensor 16b, and the one end 46c and the sensor 16c are arranged at common angular positions around the optical axis L.

[0035] 7A, the elastic member 42a is formed such that an angle α between a perpendicular line from one end 46a to the optical axis L and a perpendicular line from the other end 48a to the optical axis L is 180°. Similarly, as shown in FIG. 7B, the elastic member 42b is formed such that an angle β between a perpendicular line from one end 46b to the optical axis L and a perpendicular line from the other end 48b to the optical axis L is 180°. Also, as shown in FIG. 7C, the elastic member 42c is formed such that an angle γ between a perpendicular line from one end 46c to the optical axis L and a perpendicular line from the other end 48c to the optical axis L is 180°.

[0036] In this way, by setting the angles α, β, and γ to 180°, rotation of the lens 20 (rotation about the optical axis L) accompanying movement of the lens unit 12 is prevented. The angles α, β, and γ of the elastic members 42a, 42b, and 42c are 180°, and the elastic members 42a, 42b, and 42c are disposed at intervals of 120° about the optical axis L. Therefore, when observed from the direction of the optical axis L, the elastic members 42a, 42b, and 42c are disposed to overlap one another in the direction of the optical axis L (see FIG. 6).

[0037] In this embodiment, an example in which three elastic members are provided has been described, but four or more elastic members may be provided. In addition, in this embodiment, an example in which elastic members with angles α, β, and γ of 180° are used has been described, but the angles α, β, and γ of the elastic members may be angles other than 180° as long as they are integer multiples of 180°. When the angles α, β, and γ are 360° or more, when one elastic member is observed from the optical axis L direction, an overlapping region where this one elastic member overlaps in the optical axis L direction is generated.

[0038] [Second embodiment] A second embodiment of the present invention will be described below with reference to Figures 8 to 11. In the following description, the same members as those in the above-mentioned embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

[0039] In the second embodiment, instead of the linear motion compensation mechanism 18 (see Figs. 2 and 5) of the first embodiment described above, a linear motion compensation mechanism 50 shown in Figs. 8, 9, and 10 is provided. The linear motion compensation mechanism 50 uses a base member 54 in which an opening 52 that is slightly larger than that of the linear motion compensation mechanism 18 of the first embodiment is formed, and elastic members 56a, 56b, and 56c are disposed inside the opening 52 (inside the base member 54).

[0040] The elastic members 56a, 56b, 56c, like the elastic members 42a, 42b, 42c of the first embodiment, are arc-shaped leaf springs in which the angle between a perpendicular line from one end 58a, 58b, 58c to the optical axis L and a perpendicular line from the other end 60a, 60b, 60c to the optical axis L is 180°, and the elastic members 56a, 56b, 56c are arranged at intervals of 120° around the optical axis L. In addition, the elastic members 56a, 56b, 56c are provided within a range in which the distance from the optical axis L is greater than the distance to the outer periphery of the lens 20 and is smaller than the distance to the outer periphery of the holding frame 22.

[0041] The elastic members 56a, 56b, 56c have convex portions formed at one ends 58a, 58b, 58c that convex outward (in the direction opposite to the optical axis L), and these convex portions are fixed to the rear surface of the lens unit 12 (holding frame 22). The elastic members 56a, 56b, 56c have convex portions formed at the other ends 60a, 60b, 60c that convex outward, and these convex portions are fixed to the front surface of the base member 54.

[0042] In this manner, in the second embodiment, the elastic members 56a, 56b, and 56c are disposed inside the opening 52. For this reason, when the lens unit 12 is moved toward the rear side along the direction of the optical axis L, the rear surface of the lens unit 12 and the front surface of the base member 40 come into close contact (abut) with each other without the elastic members 56a, 56b, and 56c being sandwiched between the lens unit 12 and the base member 40.

[0043] 11, the linear motion compensation mechanism 50 of the second embodiment includes a heater 62 (unlocking member) in the form of a coiled heating wire, and a resin wire 64 (locking member) made of resin such as nylon and inserted into the center of the heater 62 (the center of the coiled heating wire). The heater 62 and the resin wire 64 are disposed inside a notch 66 formed in the base member 54 (see FIGS. 8 to 10).

[0044] In this embodiment, the notches 66 are provided at angular positions (common angular positions around the optical axis L) corresponding to the other ends 60a, 60b, 60c of the elastic members 56a, 56b, 56c, respectively, i.e., in this embodiment, three notches 66 are provided at intervals of 120° around the optical axis L (see Figs. 8 to 10). A heater 62 and a resin wire 64 are disposed in each notch 66 (see Figs. 8 to 10).

[0045] The resin wire 64 is provided to lock the lens unit 12 to the base member 40, with one end 68 fixed to the lens unit 12 and the other end 70 fixed to the base member 54 (notch 66). The lens unit 12 is locked with its rear surface in close contact with the front surface of the base member 40. The heater 62 is connected to a power source (not shown), and generates heat when electricity is applied from the power source, cutting the resin wire 64. This releases the lock on the lens unit 12.

[0046] In the second embodiment, since it is possible to lock and unlock the lens unit 12, for example, by keeping the lens unit 12 in a locked state when not in use and unlocking it when in use, it is possible to prevent problems such as displacement or damage of the lens unit 12 due to application of vibration or impact when not in use. Also, since locking and unlocking are performed with a simple configuration using a resin wire and a heater, it is possible to prevent the size from becoming large. [Explanation of symbols]

[0047] 10 Lens device 12 Lens unit 14a, 14b, 14c Drive mechanism (actuator) 16a, 16b, 16c Sensors 18 Linear motion compensation mechanism 20 Lenses 22 Retaining frame (retaining member) 24a, 24b, 24c Magnet unit (support member) 26a, 26b, 26c coils 28a, 28b, 28c ends (outside) 30a, 30b, 30c end (inside) 32a, 32b, 32c Drivers 34a, 34b, 34c ends (outside) 36a, 36b, 36c Detector 38 Processors 40 Base material 42a, 42b, 42c Elastic member 44 Aperture 46a, 46b, 46c One end (fixed end on the lens unit side) 48a, 48b, 48c: other end (fixed end on base member side) 50 Linear motion compensation mechanism 52 Aperture 54 Base material 56a, 56b, 56c Elastic member 58a, 58b, 58c One end (fixed end on the lens unit side) 60a, 60b, 60c: other end (fixed end on base member side) 62 Heater (unlocking member) 64 Resin wire (locking member) 66 Notch 68 One end (fixed end on lens unit side) 70 Other end (fixed end on base member side) L optical axis Angles between α, β, and γ

Claims

1. A holding member for holding the lens; a drive mechanism for moving the holding member along the optical axis direction; a base member provided in front of or behind the holding member in the optical axis direction; an elastic member having one end fixed to the base member and the other end fixed to the holding member, the elastic member restricting an angle change of the holding member caused by the movement, The elastic member is provided within a range in which a distance from the optical axis is larger than an outer periphery of the lens and smaller than an outer periphery of the holding member. Lens device.

2. The change in angle is a tilt of the holding member with respect to the optical axis. The lens device according to claim 1 .

3. The elastic member is provided in plurality around the optical axis. The lens device according to claim 2 .

4. the elastic member is formed in an arc shape, and when observed from the optical axis direction, at least a portion of adjacent elastic members is arranged to overlap in the optical axis direction. The lens device according to claim 3 .

5. The elastic member is a leaf spring. The lens device according to claim 4.

6. When observed from the optical axis direction, an angle between a perpendicular line from the one end to the optical axis and a perpendicular line from the other end to the optical axis is an integer multiple of 180°. The lens device according to claim 5 .

7. The angle is 360° or more, When one elastic member is observed from the optical axis direction, the one elastic member has an overlapping region in the optical axis direction. The lens device according to claim 6.

8. The elastic members are provided in three pieces at intervals of 120° around the optical axis. The lens device according to claim 3 .

9. the drive mechanism is an actuator including a support member having a magnet and a coil fixed to the holding member, The driving mechanism is provided in three positions at intervals of 120° around the optical axis, corresponding to positions at which the elastic member is fixed to the base member. The lens device according to claim 8.

10. a locking member that locks the holding member to an end portion on one end side in the optical axis direction; and a lock release member for releasing the lock. The lens device according to any one of claims 1 to 9.

11. The locking member is a resin wire, The unlocking member is a heater that heats and cuts the resin wire. The lens device according to claim 10.

12. a sensor for detecting a position of the holding member or a deformation amount of the elastic member; a processor for controlling the drive mechanism using information from the sensor. The lens device according to any one of claims 1 to 9.

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