Imaging device

Abstract

To provide an imaging device in which a plurality of optical filters are selectively arranged in front of the imaging plane of an imaging element, wherein access to the imaging plane of the imaging element is facilitated.SOLUTION: The imaging device comprises an imaging element which has an imaging plane which light from a subject enters, a first filter unit 16 which is provided with a first optical filter, a second filter unit 18 which is provided with a second optical filter 30, and a filter unit drive mechanism that drives each of the first and second filter units 16, 18 between a filtering position in front of the imaging plane and a retreat position that is off from the front of the imaging plane. The filter unit drive mechanism selectively executes an interlock mode in which one of the first and second filter units 16, 18 is located at the retreat position when the other of these is located at the filtering position, and a single-acting mode in which one of the first and second filter units 16, 18 is kept stopped at the retreat position while the other of these is driven.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present disclosure relates to an imaging device.

Background Art

[0002] For example, Patent Document 1 discloses an imaging device including a filter unit with a variable light transmittance. The filter unit includes a plurality of different optical filters and a disk that supports the plurality of optical filters. The plurality of optical filters are provided on the disk in a circumferential direction centered on the rotation center line of the disk. When the disk rotates, one optical filter is arranged in front of the imaging surface of the image sensor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the case of the imaging device described in Patent Document 1, the imaging surface of the image sensor cannot be accessed unless the filter unit is removed. Therefore, cleaning such as removing dust adhering to the imaging surface of the image sensor cannot be easily performed.

[0005] Therefore, an object of the present disclosure is to facilitate access to the imaging surface of an image sensor in an imaging device in which a plurality of optical filters are selectively arranged in front of the imaging surface of the image sensor.

Means for Solving the Problems

[0006] To solve the above problems, according to one aspect of the present disclosure, an image sensor having an imaging surface on which light from a subject is incident, A first filter unit comprising a first optical filter, A second filter unit equipped with a second optical filter, Each of the first and second filter units is provided with a filter unit drive mechanism that drives them between a filtering position in front of the imaging surface and a retracted position away from the front of the imaging surface. The provided imaging device includes a filter unit drive mechanism that selectively performs two modes: an interlocking mode in which, when one of the first and second filter units is in the filtering position, the other is moved to the retracted position; and a single-acting mode in which, while one of the first and second filter units is stopped in the retracted position, the other is driven. [Effects of the Invention]

[0007] According to this disclosure, in an imaging device in which multiple optical filters are selectively positioned in front of the imaging surface of an image sensor, access to the imaging surface of the image sensor becomes easier. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic front perspective view of an imaging device according to one embodiment of the present disclosure. [Figure 2] A rearward perspective view of the imaging module and the filter module in which the first filter unit is positioned in the first filtering position and the second filter unit is positioned in the second retracted position. [Figure 3] Rear perspective view of a filter module with the first filter unit positioned in the first filtering position and the second filter unit positioned in the second retracted position. [Figure 4] Rear view of the filter module with the first filter unit positioned in the first filtering position and the second filter unit positioned in the second retracted position. [Figure 5] Forward exploded perspective view of the filter module [Figure 6] Rear exploded perspective view of the filter module [Figure 7] Rear perspective view of the filter module with the first filter unit positioned in the first retracted position and the second filter unit positioned in the second filtering position. [Figure 8] Rear view of the filter module with the first filter unit positioned in the first retracted position and the second filter unit positioned in the second filtering position. [Figure 9] Rear perspective view of the imaging module and the filter module in a state where the first filter unit is positioned in the first retracted position and the second filter unit is positioned in the second retracted position. [Figure 10] Rear perspective view of the filter module with the first filter unit positioned in the first retracted position and the second filter unit positioned in the second retracted position. [Figure 11] Exploded perspective view of the power transmission mechanism [Figure 12] Exploded perspective view of the power transmission mechanism from a different viewpoint. [Figure 13A] Cross-sectional view of the power transmission mechanism in a coupled state [Figure 13B] Cross-sectional view of the power transmission mechanism in the uncoupled state. [Figure 14] Rear view of the rotating body [Figure 15] Front perspective view of the filter module while the imaging module is being cleaned. [Figure 16A] This diagram schematically shows the first and second rotation mechanisms in an imaging device according to another embodiment, where the first filter unit is positioned in the first filtering position and the second filter unit is positioned in the second retracted position. [Figure 16B] This diagram schematically shows the first and second rotating mechanisms in which the first filter unit is positioned in the first retracted position and the second filter unit is positioned in the second filtering position. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, a more detailed description than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate the understanding of those skilled in the art.

[0010] Note that the inventors provide the accompanying drawings and the following description so that those skilled in the art can fully understand the present disclosure, and do not intend to limit the subject matter described in the claims thereby.

[0011] Hereinafter, an imaging device according to an embodiment of the present disclosure will be described with reference to the drawings.

[0012] FIG. 1 is a schematic front perspective view of an imaging device according to an embodiment of the present disclosure. The X - Y - Z orthogonal coordinate system shown in the figure is for facilitating the understanding of the embodiment of the present disclosure and does not limit the embodiment of the present disclosure. The X - axis direction is the front - rear direction of the imaging device, the Y - axis direction is the left - right direction, and the Z - axis direction is the height direction. Note that the side where the subject exists during shooting is defined as the front side of the imaging device.

[0013] As shown in FIG. 1, an imaging device 10 according to an embodiment of the present disclosure has a filter module 12.

[0014] FIG. 2 is a rear perspective view of the filter module in a state where the imaging module and the first filter unit are arranged at the first filtering position and the second filter unit is arranged at the second retracted position. Further, FIG. 3 is a rear perspective view of the filter module in a state where the first filter unit is arranged at the first filtering position and the second filter unit is arranged at the second retracted position. That is, FIG. 3 corresponds to FIG. 2 with the imaging module omitted.

[0015] Furthermore, Figure 4 is a rear view of the filter module with the first filter unit positioned in the first filtering position and the second filter unit positioned in the second retracted position. Figures 5 and 6 are exploded perspective views of the front and rear of the filter module, respectively.

[0016] As shown in Figures 2 to 6, in this embodiment, the filter module 12 includes a housing 14, a first filter unit 16, and a second filter unit 18.

[0017] The housing 14 is made of a metal material such as aluminum die-cast and supports the first and second filter units 16 and 18. In this embodiment, the housing 14 also includes protective glass 20 through which light from the subject passes.

[0018] As shown in Figures 2, 5, and 6, the imaging device 10 has an imaging module 22 that is positioned at a distance from the protective glass 20 and faces the direction of the extension of the optical axis LA of the imaging device 10 (i.e., the front-to-back direction of the imaging device 10 (X-axis direction)), and into which light from the subject is incident. The imaging module 22 contains an image sensor (not shown) inside. The image sensor is a photoelectric conversion element such as a CCD or CMOS, and creates image data of the subject from the light from the subject (image of the subject) incident on its imaging surface via the protective glass 20. The optical axis LA is perpendicular to the imaging surface of the image sensor and passes through the center of the rectangular imaging surface. Also, as shown in Figure 5, in this embodiment, the imaging module 22 is positioned in front of the image sensor and includes a transparent cover glass 24 that covers and protects the imaging surface of the image sensor.

[0019] In this embodiment, as shown in Figures 5 and 6, the first filter unit 16 comprises a first optical filter 26 and a frame-shaped first frame structure 28 that supports the outer periphery of the first optical filter 26. The second filter unit 18 comprises a second optical filter 30 and a second frame structure 32 that supports the outer periphery of the second optical filter 30.

[0020] In this embodiment, the first optical filter 26 is an electronic ND filter with adjustable light transmittance, such as a liquid crystal filter. By changing the drive voltage applied to the first optical filter 26, the light transmittance of the first optical filter 26 is changed. The second optical filter 30 is a filter with fixed light transmittance, such as glass. In this embodiment, the first and second optical filters 26 and 30 are rectangular in shape, similar to the imaging surface of the image sensor in the imaging module 22.

[0021] The first frame structure 28, which supports the first filter unit 16, i.e., the first optical filter 26, is supported on the housing 14 so as to be rotatable about a rotation centerline C1 extending in the front-to-back direction (X-axis direction) of the imaging device 10. The second frame structure 32, which supports the second filter unit 18, i.e., the second optical filter 30, is supported on the housing 14 so as to be rotatable about a rotation centerline C2 extending in the front-to-back direction of the imaging device 10.

[0022] In this embodiment, as shown in Figures 5 and 6, the rotation centerlines C1 and C2 are located on the same straight line. Therefore, the first filter unit 16 rotates forward relative to the second filter unit 18. Because the rotation centerlines C1 and C2 are located on the same straight line, the support shaft 34 that rotatably supports the first and second filter units 16 and 18 can be made common.

[0023] As shown in Figures 5 and 6, the filter module 12 includes a first rotation mechanism 36 that rotates the first filter unit 16 about the rotation centerline C1, and a second rotation mechanism 38 that rotates the second filter unit 18 about the rotation centerline C2.

[0024] In this embodiment, the first and second rotating mechanisms 36 and 38 are so-called rack and pinion mechanisms.

[0025] The first rotation mechanism 36 extends in the left-right direction (Y-axis direction) of the imaging device 10 and includes a first rack 40 supported by the housing 14 so as to be movable in that direction, and a first drive gear 42 that engages with the first rack 40 and moves it in the left-right direction. The first rack 40 engages with a first pinion portion 28a formed on the first frame structure 28 of the first filter unit 16. As the first rack 40 moves in the left-right direction due to the rotation of the first drive gear 42, the first pinion portion 28a rotates about the rotation center line C1. As a result, the first filter unit 16 rotates about the rotation center line C1.

[0026] The second rotation mechanism 38 extends in the left-right direction (Y-axis direction) of the imaging device 10 and includes a second rack 44 supported by the housing 14 so as to be movable in that direction, and a second drive gear 46 that engages with the second rack 44 and moves in the left-right direction. The second rack 44 extends rearward and parallel to the first rack 40. The second rack 44 also engages with a second pinion portion 32a formed on the second frame structure 32 of the second filter unit 18. As the second rack 44 moves in the left-right direction due to the rotation of the second drive gear 46, the second pinion portion 32a rotates about the rotation center line C2. As a result, the second filter unit 18 rotates about the rotation center line C2.

[0027] The first filter unit 16 rotates around the rotation centerline C1 between a first filtering position and a first retracted position by the first rotation mechanism 36. The second filter unit 18 rotates around the rotation centerline C2 between a second filtering position and a second retracted position by the second rotation mechanism 38.

[0028] As shown in Figures 3 and 4, the first filter unit 16 is rotated by the first rotation mechanism 36 to be positioned in the first filtering position. Specifically, when the first filter unit 16 is in the first filtering position, the first optical filter 26 is located in front of the imaging surface of the image sensor in the imaging module 22 (i.e., in front of the cover glass 24). As a result, light from the subject passes through the first optical filter 26 before it reaches the imaging surface of the image sensor by passing through the protective glass 20. Consequently, the light from the subject that has been filtered by the first optical filter 26 passes through the cover glass 24 and enters the imaging surface of the image sensor in the imaging module 22.

[0029] Furthermore, when the first filter unit 16 is positioned in the first filtering position, the second filter unit 18 is rotated by the second rotation mechanism 38 to a second retracted position. Specifically, the second filter unit 18 is retracted to a position away from the front of the imaging module 22 as the second retracted position. In this embodiment, the second filter unit 18 is retracted to the left from the front of the imaging module 22 (when viewed from the front of the imaging device 10). As a result, light from the subject is incident on the imaging surface of the image sensor in the imaging module 22 without being obstructed by the second filter unit 18, that is, without passing through the second optical filter 30.

[0030] Figures 7 and 8 are rear perspective and rear view views of the filter module, with the first filter unit positioned in the first retracted position and the second filter unit positioned in the second filtering position.

[0031] As shown in Figures 7 and 8, the first filter unit 16 is rotated by the first rotation mechanism 36 and positioned in a first retracted position. Specifically, the first filter unit 16 is retracted to a position away from the front of the imaging module 22 as the first retracted position. In this embodiment, the first filter unit 16 is retracted to the left from the front of the imaging module 22 (when viewed from the front of the imaging device 10). As a result, light from the subject is incident on the imaging surface of the image sensor in the imaging module 22 without being obstructed by the first filter unit 16, that is, without passing through the first optical filter 26.

[0032] Furthermore, when the first filter unit 16 is positioned in the first retracted position, the second filter unit 18 is rotated by the second rotation mechanism 38 to be positioned in the second filtering position. Specifically, when the second filter unit 18 is in the second filtering position, the second optical filter 30 is located in front of the imaging surface of the image sensor in the imaging module 22. As a result, light from the subject passes through the second optical filter 30 before reaching the imaging surface of the image sensor through the protective glass 20. Consequently, the light from the subject that has been filtered by the second optical filter 30 passes through the cover glass 24 and enters the imaging surface of the image sensor. The second filtering position is located behind the first filtering position.

[0033] In this embodiment, as shown in Figures 4 and 8, the first filter unit 16 is rotated substantially 90 degrees around the rotation center line C1 by the first rotation mechanism 36. Therefore, the positional relationship between the first filtering position and the first retracted position is such that when the first filter unit 16 located in one of the first filtering position and the first retracted position is rotated 90 degrees, it is positioned in the other position. As a result, the orientation of the first optical filter 26 of the first filter unit 16 located in the first filtering position differs by 90 degrees from the orientation of the first optical filter 26 when it is located in the first retracted position. That is, the longitudinal direction of the first optical filter 26 changes from the left-right direction (Y-axis direction) of the imaging device 10 to the height direction (Z-axis direction).

[0034] Furthermore, in this embodiment, as shown in Figures 4 and 8, the second filter unit 18 is rotated substantially 90 degrees around the rotation centerline C2 by the second rotation mechanism 38. Therefore, the positional relationship between the second filtering position and the second retracted position is such that when the second filter unit 18 located in one of the second filtering position and the second retracted position is rotated 90 degrees, it is positioned in the other position. As a result, the orientation of the second optical filter 30 of the second filter unit 18 located in the second filtering position differs by 90 degrees from the orientation of the second optical filter 30 when located in the second retracted position. In other words, the longitudinal direction of the second optical filter 30 changes from the left-right direction (Y-axis direction) of the imaging device 10 to the height direction (Z-axis direction).

[0035] In the state of the filter module 12 shown in Figures 3, 4, 7, and 8, the first filter unit 16 and the second filter unit 18 do not overlap each other in the front-to-back direction (X-axis direction) of the imaging device 10. That is, neither the first filter unit 16 nor the second filter unit 18 are positioned in a filtering position or a retracted position while overlapping each other.

[0036] Figure 9 is a rear perspective view of the imaging module and the filter module with the first filter unit positioned in the first retracted position and the second filter unit positioned in the second retracted position. Figure 10 is a rear perspective view of the filter module with the first filter unit positioned in the first retracted position and the second filter unit positioned in the second retracted position. In other words, Figure 10 corresponds to Figure 9, in which the imaging module is omitted.

[0037] As shown in Figures 9 and 10, the first filter unit 16 and the second filter unit 18 are located in the first and second retracted positions, respectively, and overlap each other in the front-to-back direction (X-axis direction) of the imaging device 10. As a result, the first filter unit 16 and the second filter unit 18 are not present between the protective glass 20 and the imaging module 22. In other words, the first and second optical filters 26 and 30 are not present in front of the image sensor in the imaging module 22.

[0038] Therefore, the imaging device 10 is configured to be switchable between a first state shown in Figures 3 and 4, a second state shown in Figures 7 and 8, and a third state shown in Figures 9 and 10.

[0039] Specifically, in this embodiment, the first rotating mechanism 36 and the second rotating mechanism 38 receive power from the power transmission mechanism.

[0040] Figures 11 and 12 are exploded perspective views of the power transmission mechanism from different viewpoints. Figure 13A is a cross-sectional view of the power transmission mechanism in the coupled state, and Figure 13B is a cross-sectional view of the power transmission mechanism in the uncoupled state.

[0041] As shown in Figures 11 and 12, the power transmission mechanism 50, which transmits power to rotate the first filter unit 16 and the second filter unit 18, works in cooperation with the first rotation mechanism 36 and the second rotation mechanism 38 to construct a filter unit drive mechanism. The filter unit drive mechanism is configured to selectively perform an interlocking mode that drives both the first and second filter units 16 and 18, and a single-acting mode that drives only one of them.

[0042] Specifically, in the interlocking mode, as shown in Figures 3, 4, 7, and 8, the first and second filter units 16 and 18 are interlocked by the filter unit drive mechanism such that when one of the first and second filter units 16 and 18 is in the filtering position, the other is in the retracted position.

[0043] Furthermore, in single-acting mode, as shown in Figures 9 and 10, one of the first and second filter units 16 and 18 is stopped in the retracted position while the other is driven by the filter unit drive mechanism. In this embodiment, in single-acting mode, the second filter unit 18 is driven while the first filter unit 16 is stopped in the first retracted position.

[0044] To selectively execute linked mode and independent mode, the power transmission mechanism 50 in the filter unit drive mechanism is configured to selectively transmit power to the first rotation mechanism 36 that rotates the first filter unit 16 and the second rotation mechanism 38 that rotates the second filter unit 18. In this embodiment, in linked mode, the power transmission mechanism 50 is driven and connected to both the first and second rotation mechanisms 36 and 38. In independent mode, the power transmission mechanism 50 is driven and connected to the second rotation mechanism 38 while releasing the power connection to the first rotation mechanism 36.

[0045] As shown in Figures 11 and 12, the power transmission mechanism 50 includes a first transmission gear 52 that transmits power to a first rotating mechanism 36, a second transmission gear 54 that transmits power to a second rotating mechanism 38, and a rotating body 56 that rotates in response to an external force. In this embodiment, the rotating body 56 is a rotary knob that is rotated by the user.

[0046] In this embodiment, as shown in Figure 6, the first transmission gear 52 engages with the first drive gear 42 of the first rotation mechanism 36 via the reversing gear 58. The second transmission gear 54 directly engages with the second drive gear 46 of the second rotation mechanism 38.

[0047] In this embodiment, the first transmission gear 52, the second transmission gear 54, and the rotating body 56 rotate around a common rotation centerline C3 that extends in the front-to-back direction (X-axis direction) of the imaging device 10. The first transmission gear 52 is releasably driven and connected to the rotating body 56. The second transmission gear 54 is permanently (i.e., irremovably) driven and connected to the rotating body 56.

[0048] Specifically, as shown in Figures 11, 12, 13A, and 13B, the second transmission gear 54 and the rotating body 56 are driven together via a connecting shaft 60. The connecting shaft 60 comprises a shaft portion 60a with a hexagonal cross-section and a head portion 60b provided at one end (the front end) of the shaft portion 60a. The second transmission gear 54 and the rotating body 56 have hexagonal through holes 54a and 56a through which the shaft portion 60a of the connecting shaft 60 passes. This connecting shaft 60 drives the second transmission gear 54 and the rotating body 56 together at all times, allowing them to rotate synchronously. A stopper screw 62 is attached to the other end (the rear end) of the shaft portion 60a of the connecting shaft 60 to prevent the second transmission gear 54 from falling off the connecting shaft 60.

[0049] The first transmission gear 52 is rotatably supported by the second transmission gear 54. Specifically, the first transmission gear 52 comprises a cylindrical portion 52a and a gear portion 52b provided at the rear end of the cylindrical portion 52a and engaging with the reversing gear 58. The second transmission gear 54 comprises a cylindrical portion 54b and a gear portion 54c provided at the rear end of the cylindrical portion 54b and engaging with the second drive gear 46. The first transmission gear 52 is rotatably supported by the second transmission gear 54 by inserting the cylindrical portion 54b of the second transmission gear 54 into the cylindrical portion 52a of the first transmission gear 52.

[0050] Furthermore, the first transmission gear 52 is positioned between the rotating body 56 and the second transmission gear 54, and engages with the rotating body 56 in the direction of extension of the rotation centerline C3 (X-axis direction).

[0051] Figure 14 is a rear view of the rotating body.

[0052] As shown in Figures 12 and 14, the rotating body 56 comprises an outer cylindrical portion 56b that is grasped by the user and an inner cylindrical portion 56c that is inserted into the cylindrical portion 52a of the first transmission gear 52. Between the outer cylindrical portion 56b and the inner cylindrical portion 56c, two arc-shaped engaging claw portions 56d are concentrically formed, protruding toward the first transmission gear 52 and viewed in the direction of extension of the rotation centerline C3 (viewed in the X-axis direction).

[0053] As shown in Figure 11, two engaging claws 52c that engage with two engaging claws 56d of the rotating body 56 are formed at the tip of the cylindrical portion 52a of the first transmission gear 52. As shown in Figure 14, the two engaging claws 52c of the first transmission gear 52 enter the space between the two engaging claws 56d of the rotating body 56, causing the first transmission gear 52 and the rotating body 56 to engage with each other and drive each other. As a result, when the rotating body 56 rotates around the rotation center line C3, the first transmission gear 52 rotates.

[0054] As shown in Figure 14, in the rotating body 56, an arc-shaped space 56e is provided between the outer cylindrical portion 56b and the two engaging claw portions 56d, when viewed in the direction of extension of the rotation centerline C3 (viewed in the X-axis direction). The arc-shaped projection 14a of the housing 14 shown in Figure 5 is positioned in this space 56e. When the rotating body 56 rotates, the arc-shaped projection 14a moves within the space 56e. The rotation stroke of the rotating body 56 is restricted by this arc-shaped projection 14a.

[0055] The rotating body 56 is mounted on the power transmission mechanism 50 so as to be slidable in the direction extending along the rotation centerline C3. In this embodiment, the rotating body 56 slides along the shaft portion 60a of the connecting shaft 60. This sliding causes the rotating body 56 to engage with or disengage from the first transmission gear 52. As a result, the rotating body 56 and the first transmission gear 52 drive each other or disengage from each other.

[0056] Furthermore, in order to maintain engagement (drive connection) between the rotating body 56 and the first transmission gear 52, the rotating body 56 is biased toward the first transmission gear 52 by a spring 64. A recess 56f is formed at the front end of the rotating body 56 to accommodate the head 60b of the connecting shaft 60 and the spring 64. The spring 64 is compressed between the head 60b of the connecting shaft 60 and the bottom surface of the recess 56f of the rotating body 56.

[0057] With this filter unit drive mechanism (its power transmission mechanism 50), when the user slides the rotating body 56 forward against the biasing force of the spring 64, the engagement (drive connection) between the first transmission gear 52 and the rotating body 56 is released. In other words, it switches from linked mode to single-acting mode.

[0058] In the linked mode (when the user is not sliding the rotating body 56 forward), when the user rotates the rotating body 56, both the first transmission gear 52 and the second transmission gear 54 rotate synchronously. This causes the first drive gear 42, which is driven by the first transmission gear 52, to move the first rack 40, thereby rotating the first pinion portion 28a of the frame structure 28 of the first filter unit 16. As a result, the first filter unit 16 rotates around the rotation centerline C1. At the same time, the second drive gear 46, which is driven by the second transmission gear 54, moves the second rack 44, thereby rotating the second pinion portion 32a of the frame structure 32 of the second filter unit 18. As a result, the second filter unit 18 rotates around the rotation centerline C2. At this time, since a reversing gear 58 exists between the first transmission gear 52 and the first drive gear 42, the second filter unit 18 rotates in the opposite direction to the first filter unit 16.

[0059] Therefore, in the linked mode, when the user rotates the rotating body 56 in one direction, the first filter unit 16 moves from the first filtering position to the first retracted position, and at the same time, the second filter unit 18 moves from the second retracted position to the second filtering position. Also, when the rotating body 56 is rotated in the other direction, the first filter unit 16 moves from the first retracted position to the first filtering position, and at the same time, the second filter unit 18 moves from the second filtering position to the second retracted position.

[0060] In single-acting mode (when the user slides the rotating body 56 forward and holds it in place), when the user rotates the rotating body 56, only the second transmission gear 54 rotates. Meanwhile, the rotating body 56 rotates freely relative to the first transmission gear 52.

[0061] With this single-acting mode, as shown in Figures 9 and 10, the first filter unit 16 can be positioned in a first retracted position and the second filter unit 18 can be positioned in a second retracted position.

[0062] First, in linked mode, as shown in Figures 7 and 8, the first filter unit 16 is positioned in the first retracted position and the second filter unit 18 is positioned in the second filtering position. In this state, the system is switched to single-acting mode. When the rotating body 56 rotates in single-acting mode, the first filter unit 16 remains stopped in the first retracted position, while the second filter unit 18 moves from the second filtering position to the second retracted position. As a result, the first and second filter units 16 and 18 are no longer present between the protective glass 20 and the imaging module 22. Consequently, it becomes possible to access the imaging module 22 from the front.

[0063] Figure 15 is a front perspective view of the filter module while the imaging module is being cleaned.

[0064] When the first and second filter units 16 and 18 are not present between the protective glass 20 and the imaging module 22, the cover glass 24 of the imaging module 22 becomes accessible from the front, as shown in Figure 15. In this embodiment, the protective glass 20 is supported by a support frame 70. The support frame 70 is fixed to the housing 14 via a plurality of fixing screws 72. Therefore, when the support frame 70 is removed from the housing 14, the cover glass 24 of the imaging module 22 is exposed to the outside through the opening 14b of the housing 14 that was blocked by the protective glass 20. As a result, the cover glass 24 can be accessed. For example, dust and other debris adhering to the cover glass 24 can be removed by cleaning.

[0065] Furthermore, not only the cover glass 24 of the imaging module 22, but also the front surfaces of the optical filters 26 and 30 of the first and second filter units 16 and 18 are similarly accessible. That is, as shown in Figures 3 and 4, when the first filter unit 16 is in the first filtering position, the front surface of the first optical filter 26 is accessible. Also, as shown in Figures 7 and 8, when the second filter unit 18 is in the second filtering position, the front surface of the second optical filter 30 is accessible.

[0066] According to this embodiment, in an imaging device 10 in which the first and second optical filters 26 and 30 are selectively positioned in front of the imaging surface of the image sensor (specifically, the cover glass 24 of the imaging module 22), access to the imaging surface of the image sensor becomes easier.

[0067] Specifically, both the first and second filter units 16 and 18, each equipped with a first and second optical filter 26 and 30, can be moved away from the front of the imaging surface of the image sensor. As a result, the imaging surface of the image sensor can be accessed without removing the first and second filter units 16 and 18.

[0068] Although embodiments of this disclosure have been described above with reference to the embodiments described above, the embodiments of this disclosure are not limited to the embodiments described above.

[0069] For example, in the above-described embodiment, in single-acting mode, the drive connection between the rotating body 56 and the first transmission gear 52 (i.e., the first filter unit 16) is released, while the drive connection between the rotating body 56 and the second transmission gear 54 (i.e., the second filter unit 18) is maintained. However, the embodiments of this disclosure are not limited thereto. In single-acting mode, the drive connection between the rotating body and the first filter unit may be maintained, while the drive connection between the rotating body and the second filter unit may be released.

[0070] In the embodiments described above, the first and second filter units 26 and 30 are rotated by the first and second rotating mechanisms 36 and 38, respectively, as shown in Figures 5 and 6, as well as by the so-called rack and pinion mechanisms. However, the embodiments of this disclosure are not limited thereto.

[0071] Figures 16A and 16B schematically show the first and second rotation mechanisms in an imaging device according to another embodiment. Figure 16A shows the state in which the first filter unit 116 is positioned in the first filtering position and the second filter unit 118 is positioned in the second retracted position. Figure 16B also shows the state in which the first filter unit 116 is positioned in the first retracted position and the second filter unit 118 is positioned in the second filtering position.

[0072] In the imaging apparatus according to another embodiment shown in Figures 16A and 16B, the first rotation mechanism 136 and the second rotation mechanism 138 that rotate the first filter unit 116 and the second filter unit 118, respectively, are so-called lever-crank mechanisms. The first rotation mechanism 136 and the second rotation mechanism 138 have substantially the same configuration. Furthermore, the rotation centerline C1 of the first filter unit 116 and the rotation centerline C2 of the second filter unit 118 are located on the same straight line.

[0073] The first rotating mechanism 136, which is a so-called lever-crank mechanism, includes a crank 170 with one end connected to a rotating body 156, a lever 172 with one end connected to a first filter unit 116, and a link 174 having one end rotatably connected to the other end of the crank 170 and the other end rotatably connected to the other end of the lever 172.

[0074] Furthermore, the first rotating mechanism 138, which is a so-called lever-crank mechanism, includes a crank 176 with one end connected to the rotating body 156, a lever 178 with one end connected to the second filter unit 118, and a link 180 having one end rotatably connected to the other end of the crank 176 and the other end rotatably connected to the other end of the lever 172.

[0075] As shown in Figure 16A, when the rotating body 156 rotates clockwise around the rotation centerline C3, the crank 170 pulls the lever 172 via the link 174. As a result, the first filter unit 116 rotates clockwise around the rotation centerline C1 and moves from the first filtering position to the first retracted position shown in Figure 16B. At the same time, the crank 176 pushes the lever 178 via the link 180. As a result, the second filter unit 118 rotates counterclockwise around the rotation centerline C2 and moves from the second retracted position to the second filtering position shown in Figure 16B.

[0076] As shown in Figure 16B, when the rotating body 156 rotates counterclockwise around the rotation centerline C3, the first filter unit 116 rotates counterclockwise around the rotation centerline C1 via the crank 170, lever 172, and link 174. As a result, the first filter unit 116 moves from the first retracted position to the first filtering position shown in Figure 16A. Simultaneously, the second filter unit 118 rotates clockwise around the rotation centerline C2 via the crank 176, lever 178, and link 180. As a result, the second filter unit 118 moves from the second filtering position to the second retracted position shown in Figure 16A.

[0077] In this alternative embodiment, one of the cranks, the crank 170 in the first rotating mechanism 136 and the crank 176 in the second rotating mechanism 138, is permanently driven-connected to the rotating body 156, while the other is releasably driven-connected to the rotating body 156.

[0078] Furthermore, in the above-described embodiment, the rotating body 56 is rotated by the user and slid by the user in the direction of extension of the rotation centerline C3 (X-axis direction). However, the embodiments of this disclosure are not limited thereto. For example, the rotating body may be rotationally driven by a motor and slid by an actuator. That is, the rotating body may be mounted on the output shaft of the motor so as to be slidable in the direction of extension of the rotation centerline of the motor, and the actuator may slide the rotating body in the direction of the rotation centerline.

[0079] Furthermore, in the embodiment described above, the first filter unit 16 rotates between a first filtering position and a first retracted position by a first rotation mechanism 36. The second filter unit 18 rotates between a second filtering position and a second retracted position by a second rotation mechanism 38. However, the embodiments of this disclosure are not limited thereto. The first and second filter units may also be moved in parallel between the filtering position and the retracted position.

[0080] In other words, the imaging device according to the embodiment of the present disclosure broadly comprises an image sensor having an imaging surface into which light from a subject is incident, a first filter unit having a first optical filter, a second filter unit having a second optical filter, and a filter unit drive mechanism that drives the first and second filter units, respectively, between a filtering position in front of the imaging surface and a retracted position away from the front of the imaging surface, wherein the filter unit drive mechanism selectively performs an interlocking mode in which, when one of the first and second filter units is in the filtering position, the other is in the retracted position, and a single-act mode in which, while one of the first and second filter units is stopped in the retracted position, the other is driven.

[0081] As described above, the embodiments described in this disclosure have been explained as examples of the technology. For this purpose, drawings and a detailed description are provided. Therefore, among the components described in the drawings and detailed description, there may be not only components that are essential for solving the problem, but also components that are not essential for solving the problem, in order to illustrate the technology described above. For this reason, the mere fact that these non-essential components are described in the drawings and detailed description should not be immediately assumed to be essential.

[0082] Furthermore, since the embodiments described above are for illustrative purposes of the technology described herein, various modifications, substitutions, additions, omissions, etc., can be made within the scope of the claims or equivalents thereof. [Industrial applicability]

[0083] This disclosure is applicable to imaging devices in which a plurality of optical filters are selectively positioned in front of the imaging surface of an image sensor. [Explanation of Symbols]

[0084] 16. First filter unit 18. Second filter unit 26. First optical filter 30. Second optical filter

Claims

1. The casing and An image sensor is placed inside the aforementioned housing and has an imaging surface into which light from the subject enters; A filter module comprising a first filter unit having a first optical filter and a second filter unit having a second optical filter, disposed inside the housing, Each of the first and second filter units is provided with a filter unit drive mechanism that drives them between a filtering position in front of the imaging surface and a retracted position away from the front of the imaging surface. The filter unit drive mechanism selectively performs an interlocking mode in which, when one of the first and second filter units is in the filtering position, the other is moved to the retracted position, and a single-acting mode in which, while one of the first and second filter units is stopped in the retracted position, the other is driven. The imaging device is configured such that the image sensor is positioned adjacent to the filter module in the direction of incidence to the imaging surface.

2. An image sensor having an imaging surface into which light from the subject enters, A first filter unit comprising a first optical filter, A second filter unit comprising a second optical filter, Each of the first and second filter units is provided with a filter unit drive mechanism that drives them between a filtering position in front of the imaging surface and a retracted position away from the front of the imaging surface. The filter unit drive mechanism, A first rotation mechanism for rotating the first filter unit between the filtering position and the retracted position, A second rotation mechanism for rotating the second filter unit between the filtering position and the retracted position, The system includes a power transmission mechanism that selectively transmits power to each of the first and second rotating mechanisms, The filter unit drive mechanism selectively performs an interlocking mode in which, when one of the first and second filter units is in the filtering position, the other is moved to the retracted position, and a single-acting mode in which, while one of the first and second filter units is stopped in the retracted position, the other is driven. In the aforementioned interlocking mode, the power transmission mechanism is driven and connected to both the first and second rotation mechanisms. In the single-acting mode, the power transmission mechanism drives and connects to one of the first and second rotating mechanisms while releasing the drive connection to the other, in an imaging device.

3. The power transmission mechanism includes a first transmission gear that transmits power to the first rotation mechanism, a second transmission gear that transmits power to the second rotation mechanism, and a rotating body that rotates when subjected to an external force. One of the first and second transmission gears is permanently driven and connected to the rotating body. The imaging apparatus according to claim 2, wherein the other of the first and second transmission gears is releasably driven and connected to the rotating body.

4. The first transmission gear, the second transmission gear, and the rotating body rotate around a common centerline of rotation. The rotating body is provided in the power transmission mechanism so as to be slidable in the direction extending the rotational centerline, while maintaining a drive connection with one of the first transmission gear and the second transmission gear. The imaging apparatus according to claim 3, wherein the rotating body slides to engage with or disengage from the other of the first and second transmission gears.

5. The imaging apparatus according to claim 4, wherein the power transmission mechanism includes a spring that biases the rotating body toward the other of the first and second transmission gears.

6. The imaging apparatus according to any one of claims 3 to 5, wherein the rotating body is a rotary knob rotated by a user.

7. The first rotation mechanism includes a first pinion portion provided on the first filter unit, a first rack that engages with the first pinion portion, and a first drive gear that engages with the first rack and the first transmission gear. The second rotation mechanism includes a second pinion portion provided on the second filter unit, a second rack that engages with the second pinion portion, and a second drive gear that engages with the second rack and the second transmission gear. The imaging apparatus according to any one of claims 3 to 6, wherein a reversing gear is provided between the first drive gear and the first transmission gear or between the second drive gear and the second transmission gear.

Images