Lens barrel and imaging device

Abstract

To provide a lens barrel that can be miniaturized while suppressing the eccentricity of multiple lenses. [Solution] A lens barrel comprising: a first fixed lens frame for holding a first lens; a second fixed lens frame for holding a second lens; a movable lens frame that moves between the first and second fixed lens frames along the optical axis direction of the lens; and a guide bar that supports the movable lens frame so as to be movable along the optical axis direction, wherein the first and second fixed lens frames are positioned perpendicular to the optical axis via the guide bar, and are positioned along the optical axis direction by the contact portion of the second fixed lens frame contacting the first fixed lens frame.

Description

Technical Field

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

Background Art

[0002] Conventionally, there is a fastening means using screws as a means for fixing a lens frame that holds a lens to a housing. However, the cost increases due to the addition of components such as screws, and a fastening space for the screws is required, making it easy for the housing to become large. In addition, there is a risk that the holding accuracy of the lens may change due to the stress caused by screw tightening. Regarding surveillance cameras that require high resolution, the stress may particularly have an impact.

[0003] In Patent Document 1, a configuration for holding a fixed lens in a housing is disclosed. Specifically, the positioning holes of the fixed lens frame are inserted through a guide bar that holds a moving lens holder and positioned simultaneously. Further, a concave portion provided on the fixed lens frame engages with a convex portion provided on the housing in the optical axis direction.

[0004] In Patent Document 2, a configuration is disclosed in which the positioning holes of the fixed lens frame are inserted through a guide bar that holds a moving lens holder and positioned simultaneously. Further, the fixed lens frame is fixed to the housing with an adhesive.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when the prior art disclosed in Patent Documents 1 and 2 is applied to the lens barrel of the present invention, a space is required for the fixed lens frame and the housing to engage, which may result in an enlarged housing. On the other hand, because the fixed lens frame is fixed to the housing, the eccentricity accuracy of the lens may deteriorate due to the positioning configuration between the housing and the fixed lens frame.

[0007] Therefore, the objective of the present invention is to provide a lens barrel that can be miniaturized while suppressing the eccentricity of multiple lenses. [Means for solving the problem]

[0008] To achieve the above objective, a lens barrel as one aspect of the present invention comprises a first fixed lens frame for holding a first lens, a second fixed lens frame for holding a second lens, a movable lens frame that moves between the first fixed lens frame and the second fixed lens frame along the optical axis direction of the lens, and a guide bar that supports the movable lens frame so as to be movable along the optical axis direction, wherein the first fixed lens frame and the second fixed lens frame are positioned in a direction perpendicular to the optical axis via the guide bar, and are positioned in a direction along the optical axis by the contact portion of the second fixed lens frame contacting the first fixed lens frame. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a lens barrel that can be miniaturized while suppressing the eccentricity of multiple lenses. [Brief explanation of the drawing]

[0010] [Figure 1] This diagram shows the configuration of the imaging device in the embodiment. [Figure 2] This is a block diagram of the imaging device in the embodiment. [Figure 3] This is a hardware configuration diagram of the imaging device in the embodiment. [Figure 4] This diagram shows the internal structure of the lens barrel. [Figure 5]This is an example of a cross-sectional view of a lens barrel in an embodiment. [Figure 6] This is an example of a perspective view of the lens barrel in an embodiment. [Modes for carrying out the invention]

[0011] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the attached drawings. The embodiments described below are examples of means for realizing the present invention and should be modified or changed as appropriate depending on the configuration of the apparatus to which the present invention is applied and various conditions, and the present invention is not limited to the embodiments described below.

[0012] <Embodiment 1> Figure 1 is a diagram showing an example of the configuration of an imaging device (camera) 7 according to this embodiment. The imaging device 7 is configured to include a cover 2, a dome cover 3, a lens barrel 4, an image sensor 5, and a pan-tilt rotation unit 6. The imaging device 7 according to this embodiment is, for example, a network camera (network surveillance camera).

[0013] The image sensor 5 has semiconductor elements such as a CMOS (Complementary Metal Oxide Semiconductor) sensor or a CCD (Charge Coupled Device) sensor. Light transmitted through the imaging optical system is imaged by the image sensor and converted into an electrical signal. The image sensor is sensitive to light in the visible light region, but is not limited to this; for example, it may be sensitive to non-visible light regions such as infrared light. The image sensor 5 is mounted on the lens barrel 4.

[0014] The pan-tilt rotation unit 6 holds the lens barrel 4 so that it can rotate in the pan (horizontal), tilt (vertical), and rotation directions. Details of the lens barrel 4 in this embodiment will be described later.

[0015] The cover 2 is an exterior member used for fixing the dome cover 3 and the pan-tilt rotation unit 6. The dome cover 3 is a cover member made of plastic (such as resin like PC (polycarbonate)) at least partially transparent or translucent. The dome cover 3 is configured, for example, in a hemispherical shape. Also, the dome cover 3 is fastened with fastening screws 1 in a state of being sandwiched between the cover 2 and the pan-tilt rotation unit 6. Thereby, the lens barrel 4, the imaging element 5, etc. are arranged inside the dome cover 3. The dome cover 3 functions as a protective cover for protecting these lens units and imaging sensors from raindrops, dust, external impacts, etc. Note that the dome cover 3 does not have to be a complete hemisphere, and a part thereof may be spherical. Or, it may be composed of a polyhedron.

[0016] Figure 2 is a block diagram of the imaging device 7 provided with the lens barrel 4 in the present embodiment. The imaging device 7 is further configured to include an aperture drive unit 9, a zoom motor 13, a focus motor 15, an image processing unit 16, a camera control unit 17, and a display unit 18.

[0017] The imaging device 7 captures the subject image formed by passing through the lens barrel 4 with the imaging element 5. The lens barrel 4 has an aperture 8 for adjusting the amount of light to be captured and an aperture drive unit 9. Further, the lens barrel 4 has a zoom lens 10 for changing the zoom magnification and a focus lens 12 for performing focus adjustment to form a good image on the imaging element 5. The zoom lens 10 is driven by the zoom motor 13. The focus lens 12 is driven by the focus motor 15. The zoom motor 13 and the focus motor 15 are drive units configured, for example, by stepping motors. Also, further, the lens barrel 4 has a fixed lens 11 and a fixed lens 14. The fixed lens 11 is arranged between the zoom lens 10 and the focus lens 12, and the fixed lens 14 is provided with the fixed lens 14 on the rear side (imaging surface side) of the focus lens 12.

[0018] The imaging device 7 further includes an image processing unit 16 and a camera control unit 17. The image processing unit 16 performs various image processes such as development processing, color balance processing, gamma processing, and noise reduction processing on the imaging data output by the imaging unit 104 described later, and generates image data and video data. The imaging information such as the image data and video data generated by the image processing unit 16 is output to the camera control unit 17. Note that it may be configured integrally with other parts of the imaging device 7 (in a common housing), or may be configured separately from other parts of the imaging device 7 (in a separate housing).

[0019] The camera control unit 17 includes a CPU, a memory, etc., is composed of at least one computer, and is connected to each component of the imaging device 7 via a line. For example, the camera control unit 17 controls the movement of the zoom lens 10 and the focus lens 12 by controlling the driving of the zoom motor 13, the focus motor 15, etc. Further, the camera control unit 17 also functions as a system control unit that comprehensively controls each component of the imaging device 7 according to a program stored in the memory, and implements setting of various parameters and data transmission / reception instructions. Note that the camera control unit 17 may be configured integrally with other parts of the imaging device 7 (in a common housing), or may be configured separately from other parts of the imaging device 7 (in a separate housing), or may be installed at a location separate from the imaging device 7 and controlled remotely.

[0020] The display unit 18 is composed of a monitor, a display, etc. The imaging information of the image data and video data generated by the image processing unit 16 is transmitted to the display unit 18 by the camera control unit 17. Thereby, the image data and video data captured by the imaging device 7 are displayed on the screen of the display unit 18. Note that the display unit 18 may be an information processing device (client device) configured integrally with the display, or may be an information processing device (client device) in which the display is connected separately via a line.

[0021] The lens barrel 4 also includes a storage unit (not shown) and a communication unit (not shown). The storage unit functions as a storage means capable of temporarily storing and retrieving one or more image data that have undergone predetermined image processing by the image processing unit 16. Furthermore, it is also used as a program storage area for programs executed by the camera control unit 17, a storage area for various parameters, and a work area during program execution. The communication unit converts imaging information such as image data stored in the storage unit into data compliant with a communication protocol and distributes it to external devices (for example, the display unit 18 or a client device). It should be noted that it is not limited to sending image (still image) data; it may also generate video data from the stored image data, apply compression encoding processing such as H.264, and then distribute it.

[0022] Figure 3 is a hardware configuration diagram of the imaging device 7 in this embodiment. The imaging device 7 is configured to include a CPU 101, ROM 102, RAM 103, imaging unit 104, storage device 105, and communication unit 106.

[0023] The CPU (processor) 101 is a central processing unit that reads control programs stored in the ROM 102 and executes various processes. The ROM 102 is a non-volatile memory that stores the programs for each embodiment and other programs (control programs) and data necessary for control. Since the ROM 102 constitutes the storage unit not shown above, a detailed explanation is omitted.

[0024] RAM 103 is a volatile memory and is used as a temporary storage area for the CPU 101, such as the main memory and work area. Since RAM 103 constitutes the storage unit not shown above, a detailed explanation is omitted. The imaging unit 104 consists of an imaging optical system composed of optical elements such as multiple lenses (for example, a zoom lens 10 and a focus lens 14) and a holder member for holding the lenses, and an image sensor 5, etc.

[0025] The storage device 105 stores various data and programs. The storage device 105 is a non-volatile storage device such as an HDD, flash memory, or SD card. In addition to being used as a persistent storage area for the OS, various programs, and various data, the storage device 105 is also used as a storage area for short-term data. Since the storage device 105 constitutes the storage unit described above, a detailed explanation is omitted. The communication unit 106 performs communication processing with external devices such as the display unit 18 and client devices via a network, etc., by wire or wireless connection. Since the communication unit 106 constitutes the communication unit (not shown) described above, a detailed explanation is omitted.

[0026] The functions and processing of the imaging device 7 are realized by the CPU 101 reading a program stored in the ROM 102 or storage device 105 and executing this program. Alternatively, the CPU 101 may read a program stored in a recording medium such as an SD card instead of the ROM 102.

[0027] In this embodiment, the imaging device 7 uses one processor (CPU 101) and one memory (ROM 11) to perform each operation, but other configurations are also possible. For example, multiple processors, multiple RAMs, ROMs, and storage devices can work together to perform each operation in the imaging device 7. Furthermore, some operations and processes may be performed using hardware circuits. Also, the functions and processes of the imaging device 7 described later may be implemented using a processor other than the CPU. Additionally, for example, a GPU (Graphics Processing Unit) may be used instead of a CPU.

[0028] Figure 4 shows the internal configuration of the lens barrel 4 in this embodiment. The lens barrel 4 in this embodiment consists of five lens groups, L1 to L5, with L1 positioned closest to the subject (incident side) and receiving the incoming light. L2 is positioned closer to the image sensor than L1, L3 is positioned closer to the image sensor than L2, L4 is positioned closer to the image sensor than L3, and L5 is positioned closer to the image sensor than L4. Here, L1 is a fixed 1-group lens. L2 is a 2-group lens that moves in a direction parallel to the optical axis OA (moves along the optical axis OA) to perform a magnification operation. L3 is a fixed 3-group lens. L4 is a 4-group lens that moves in a direction parallel to the optical axis OA to perform a focusing operation. L5 is a fixed 5-group lens, which will be described later. Thus, the lens barrel 4 in this embodiment has multiple lens groups.

[0029] The lens frame (fixed lens frame) 19 that holds the first lens group L1 is fastened and fixed to the housing 21 using four first-group fixing screws 20. The zoom movement frame 22 that holds the second lens group L2 is supported by guide bars 23 and 24 so as to be movable in the direction of the optical axis OA (a direction parallel to the optical axis OA). An aperture unit 25 is also fixed to the zoom movement frame 22.

[0030] Guide bars 23 and 24 are fixed in place by being sandwiched between housings 21 and 27. The first fixed lens frame 26, which holds the 3-group lens L3 (first lens), is fastened to housing 27 with screws (not shown). An aperture unit 25 is also fixed to the first fixed lens frame 26.

[0031] Guide bar 28 (second guide bar) and guide bar 29 (first guide bar) are fixed so as to be sandwiched between housing 21 and housing 27. Guide bar 28 and guide bar 29 are positioned in different locations, as shown in Figure 6. The focus movement frame (movable lens frame) 30 that holds the 4-group lens L4 is supported by guide bar 28 and guide bar 29 so as to be movable in the direction of the optical axis OA. In other words, guide bar 28 and guide bar 29 support the focus movement frame 30 in a direction along the optical axis OA. Furthermore, by inserting a part of the focus movement frame 30 into the opening of the second fixed lens frame 31, which will be described later (in the direction of the dotted arrow in Figure 4), the 1-group lens L1 to the 5-group lens L5 are aligned in the direction of the optical axis OA.

[0032] The second fixed lens frame 31 holds the 5-group lens L5 (the second lens). The method of holding the second fixed lens frame 31 will be explained in detail later.

[0033] The zoom motor 32 is fixed to the housing 27. Since the zoom motor 32 is part of the zoom motor 13 described above, a detailed explanation is omitted. The screw portion of the stepping motor that makes up the zoom motor 32 is engaged with a rack (not shown) connected to the zoom movement frame 22, and as the screw rotates, the zoom movement frame 22 moves in a direction parallel to the optical axis OA.

[0034] The focus motor 33 is fixed to the housing 27. Since the focus motor 33 is part of the focus motor 15 described above, a detailed explanation is omitted. The screw portion of the stepping motor that makes up the focus motor 33 engages with a rack (not shown) fixed to the focus movement frame 30, and the rotation of the screw causes the focus movement frame 30 to move along the optical axis OA direction.

[0035] A photointerrupter (not shown) is fixed to the housing 27. The same number of photointerrupters are provided as there are stepping motors. The positions of the zoom frame 22 and the focus frame 30 are detected and controlled by the output of the photointerrupters and the rotation speed of the stepping motors.

[0036] The dummy glass 34, infrared cut filter 35, filter frame 36, and filter switching actuator 37 are positioned between the housing 27 and the image sensor holder 38. The dummy glass 34 and infrared cut filter 35 are held by the filter frame 36. When the filter switching actuator 37 is driven, the dummy glass 34 and infrared cut filter 35, held by the filter frame 36, move in a direction perpendicular to the optical axis OA (orthogonal to the optical axis), and they are switched.

[0037] Next, the holding structure of the second fixed lens frame 31 will be described with reference to Figure 5. Figure 5 is an example of a cross-sectional view of the lens barrel 4 in this embodiment. Figure 5(A) is an example of a cross-sectional view of the lens barrel 4. Figure 5(B) is a cross-sectional view XX of the first fixed lens frame 26 that holds the 3-group lens L3, viewed from the front side towards the housing 27 side.

[0038] The first fixed lens frame 26, which holds the 3-group lens L3, has a bottom surface portion 39. The second fixed lens frame 31, which holds the 5-group lens L5, has a bottom surface portion 40 (contact portion). Furthermore, the second fixed lens frame 31 has a cylindrical portion 41. The bottom surface portion 40 of the second fixed lens frame 31 is formed to connect with the cylindrical portion 41. The positions of the first fixed lens frame 26 and the second fixed lens frame 31 in the direction of the optical axis OA are determined when the bottom surface portion 39 of the first fixed lens frame 26 and the bottom surface portion 40 of the second fixed lens frame 31 come into contact in the direction of the optical axis OA. In other words, the positions of the first fixed lens frame 26 and the second fixed lens frame 31 in the direction of the optical axis OA are determined when the bottom surface portion 39 and the bottom surface portion 40 come into contact in the direction of the optical axis OA.

[0039] Furthermore, the surface 42 formed on the side of the bottom surface 40 that is opposite in the optical axis OA direction contacts (abuts against) the bottom surface 43 provided on the housing 27. In other words, the second fixed lens frame 31 is held almost as one unit with the first fixed lens frame 26 and the housing 27, and is fixed by fastening fasteners 27a, 27b, and 27c, which are made of screws or bolts. With this configuration, the focus movement frame 30 that holds the 4-group lens L4 can move between the first fixed lens frame 26 and the second fixed lens frame 31 in the optical axis OA direction. Specifically, the focus movement frame 30 can move in the optical axis OA direction inside the cylindrical portion 41 provided on the second fixed lens frame 31.

[0040] Thus, in this embodiment, the focus movement frame 30 is positioned inside the cylindrical portion 41. In this embodiment, an opening is provided in the cylindrical portion 41 in order to insert the focus movement frame 30 into the cylindrical portion 41. The opening provided in the cylindrical portion 41 will be described later. The bottom surface portion 40 described above may be, for example, a flange portion, or any seating surface that can contact the bottom surface portion 39.

[0041] Figure 6 is an example of a cross-sectional view of the lens barrel 4 in this embodiment. Figure 6(A) is a perspective view of the inside of the lens barrel 4 including the lens holder portion 44 of the 3-group lens L3 to 5-group lens L5 and the housing 27. Figure 6(B) is a perspective view of the inside of the lens barrel 4 including the lens holder portion 44. Figure 6(C) is a perspective view of the inside of the lens barrel 4 including the lens holder portion 44, looking from the image sensor side towards the subject side.

[0042] The lens holding section 44 is configured to include a first fixed lens frame 26, a second fixed lens frame 31, and a focus movement frame 30. In the configuration of the lens holding section 44, the focus movement frame 30, which holds a 4-group lens L4, is positioned between the first fixed lens frame 26, which holds a 3-group lens L3, and the second fixed lens frame 31, which holds a 5-group lens L5. Guide bars 28 and 29, which are members that support the focus movement frame 30 relative to the housing 27, are inserted through the lens holding section 44. That is, guide bars 28 and 29 are inserted through the first fixed lens frame 26, the second fixed lens frame 31, and the focus movement frame 30, which constitute the lens holding section 44.

[0043] Guide bars 28 and 29 are held in the housing 27. Guide bars 28 and 29 are inserted not only into the focus movement frame 30, but also into the first fixed lens frame 26 and the second fixed lens frame 31 simultaneously. Therefore, by positioning the multiple fixed lens frames (first fixed lens frame 26, second fixed lens frame 31) with each guide bar that is also inserted into the movable lens frame (focus movement frame 30), relative eccentricity of the three lens groups with respect to the optical axis OA direction can be suppressed. By configuring the lens barrel 4 in this way, it is possible to provide a lens barrel equipped with a fixed lens holding structure that can suppress eccentricity of multiple lenses. As a result, the imaging device 7 of this embodiment can suppress eccentricity of multiple lenses and acquire better images than conventional devices.

[0044] The lens holding portion 44 will now be described in detail with reference to Figure 6(B). The guide bar 29 engages with the U-groove 45 (first engaging portion) provided on the first fixed lens frame 26, the U-groove 46 (second engaging portion) provided on the focus movement frame 30, and the U-groove 47 (third engaging portion) provided on the second fixed lens frame 31. As a result, the guide bar 29 passes between each of the lens frames of the first fixed lens frame 26, the focus movement frame 30, and the second fixed lens frame 31. That is, by engaging the guide bar 29 with the U-grooves provided on the first fixed lens frame 26, the focus movement frame 30, and the second fixed lens frame 31, the multiple fixed lens frames and the moving lens frame can be positioned.

[0045] The first fixed lens frame 26 has a protruding portion formed by extending outward, and the U-groove portion 45 is provided on this protruding portion. The focus moving frame 30 also has a protruding portion (first protruding portion) formed by extending outward, and the U-groove portion 46 is provided on this protruding portion. The second fixed lens frame 31 also has a protruding portion formed by extending outward, and the U-groove portion 47 is provided on this protruding portion.

[0046] Furthermore, the cylindrical portion 41 of the second fixed lens frame 31 is provided with an opening 48 (the first opening). The opening 48 also functions as an opening to cause a part of the focus movement frame 30, including the U-groove portion 47 provided on the focus movement frame 30, to protrude outward from the cylindrical portion 41 in the direction of the outer diameter (radially outward). Specifically, the first protruding portion of the focus movement frame 30 described above is made to protrude outward through the opening 48. That is, the portion (U-groove portion 46) that engages with the guide bar 29 provided on the focus movement frame 30 is configured to be in a position that protrudes outward from the opening in the direction of the outer diameter. With this configuration, the 3-group lens L3 to the 5-group lens L5 can be arranged with their lens centers substantially aligned in the direction of the optical axis OA.

[0047] Furthermore, with the configuration of the opening 48 in this embodiment, the mechanical strength of the cylindrical portion 41 can be maintained with a minimal opening in a cylindrical shape, thus maintaining mechanical strength compared to, for example, a shape in which the cylindrical portion 41 is cut out with a deep and wide width. As a result, deformation of each dimension of the second fixed lens frame 31 can be prevented, dimensional accuracy can be maintained, and lens eccentricity can be suppressed.

[0048] As shown in Figure 6(C), the focus movement frame 30 through which guide bars 28 and 29 are inserted is connected to the focus motor 33 and the rack 49, and moves in the direction of the optical axis OA. Guide bar 28 engages with the first positioning hole 50 (first hole) provided in the first fixed lens frame 26, the sleeve portion 51 (support portion) provided in the focus movement frame 30, and the second positioning hole 52 (second hole) provided in the second fixed lens frame 31, respectively. As a result, guide bar 28 is inserted into the first fixed lens frame 26, the focus movement frame 30, and the second fixed lens frame 31, respectively.

[0049] The first fixed lens frame 26 has another protrusion at a different position from the aforementioned protrusion which is formed by extending outwards, and the first positioning hole 50 is provided on this protrusion. The focus moving frame 30 has another protrusion (second protrusion) at a different position from the aforementioned protrusion (first protrusion) which is formed by extending outwards, and the sleeve portion 51 is provided on this protrusion. The second fixed lens frame 31 has another protrusion at a different position from the aforementioned protrusion which is formed by extending outwards, and the second positioning hole 52 is provided on this protrusion.

[0050] The sleeve portion 51 has holes on its sides for engaging the guide bar 28. One hole (the third hole) is located on the side of the sleeve portion 51 toward the imaging plane, and the other hole (the fourth hole) is located on the side of the sleeve portion 51 toward the object. Furthermore, the sleeve portion 51 has an opening between the third hole and the fourth hole in the optical axis direction OA. By engaging the guide bar 28 with the third hole and the fourth hole, the guide bar 28 engages with the sleeve portion 51.

[0051] Furthermore, the cylindrical portion 41 of the second fixed lens frame 31 has an opening 53 at a position different from the opening 48. The opening 53, which is different from the opening 48, also functions as an opening for inserting the focus movement frame 30 into the cylindrical portion 41. After inserting the focus movement frame 30 into the cylindrical portion 41, the second protruding portion of the focus movement frame 30 described above protrudes outward from the opening 53. That is, the portion (sleeve portion 51) that engages with the guide bar 28 provided on the focus movement frame 30 is configured to protrude outward from the opening. With this configuration, the 3-group lens L3 to the 5-group lens L5 can be arranged with their lens centers substantially aligned in the direction of the optical axis OA. Moreover, with the configuration of the opening 53 in this embodiment, the mechanical strength of the cylindrical portion 41 can be maintained with a minimal opening in a cylindrical shape, similar to the opening 48, thus maintaining mechanical strength compared to, for example, a shape in which the cylindrical portion 41 is cut out with a deep and wide width. Therefore, deformation of each dimension of the second fixed lens frame 31 can be prevented, maintaining dimensional accuracy and suppressing lens eccentricity.

[0052] Furthermore, the cylindrical portion 41 provided on the second fixed lens frame 31 is positioned closer to the optical axis OA center than the guide bars 28 and 29. In other words, the cylindrical portion 41 is located inward (radially inward) than the guide bars 28 and 29. This is achieved by inserting the focus movement frame 30 into the cylindrical portion 41 from the opening 53, and having the U-groove portion 46 on the focus movement frame 30 protrude from the opening 48, and the sleeve portion 51 protrude from the opening 53, thereby efficiently utilizing the space inside the lens barrel 4. This configuration allows for miniaturization of the lens barrel.

[0053] Furthermore, in this embodiment, the diameter of the 3-group lens L3 (first fixed lens) is smaller than the diameter of the 5-group lens L5 (second fixed lens). This allows the cylindrical portion 41 to be efficiently arranged in the space inside the lens barrel 4, and further miniaturization of the lens barrel is possible.

[0054] As described above, the lens barrel 4 of this embodiment comprises a first fixed lens frame 26, a second fixed lens frame 31, and a focus movement frame 30 that moves between the first fixed lens frame 26 and the second fixed lens frame along the direction of the optical axis OA. Furthermore, it is provided with guide bars 28 and 29 that support the focus movement frame 30 so as to be movable along the direction of the optical axis OA. The first fixed lens frame 26 and the second fixed lens frame 31 are positioned in a direction perpendicular to the optical axis OA via the guide bars 28 and 29. Furthermore, the first fixed lens frame 26 and the second fixed lens frame 31 are positioned in a direction along the optical axis by the bottom surface 40 of the second fixed lens frame 31 contacting the bottom surface 39 of the first fixed lens frame 26.

[0055] As described above, the imaging device 7 of this embodiment provides a lens barrel 4 equipped with a fixed lens holding structure that can suppress the eccentricity of multiple lenses while enabling miniaturization.

[0056] Although preferred embodiments of the present invention have been described above with reference to examples and figures, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its essence.

[0057] This embodiment includes the following configuration.

[0058] (Composition 1) A first fixed lens frame that holds the first lens, A second fixed lens frame that holds the second lens, A movable lens frame that moves along the optical axis of the lens between the first fixed lens frame and the second fixed lens frame, The movable lens frame is supported by a guide bar that allows it to move along the optical axis, The first fixed lens frame and the second fixed lens frame are positioned perpendicular to the optical axis via the guide bar, and are also positioned along the optical axis by the contact portion of the second fixed lens frame contacting the first fixed lens frame. A lens barrel characterized by the following features.

[0059] (Configuration 2) The lens barrel according to configuration 1, characterized in that the movable lens frame is arranged inside the second fixed lens frame.

[0060] (Composition 3) The lens barrel according to configuration 1 or 2, characterized in that the guide bar engages with the respective engaging portions of the first fixed lens frame, the movable lens frame, and the second fixed lens frame, thereby passing between each lens frame, including the first fixed lens frame, the second fixed lens frame, and the movable lens frame.

[0061] (Composition 4) The lens barrel according to any one of configurations 1 to 3, characterized in that the guide bar includes a first guide bar and a second guide bar positioned differently from the first guide bar.

[0062] (Composition 5) The lens barrel according to configuration 4, characterized in that the first guide bar engages with the first engaging portion of the first fixed lens frame, the third engaging portion of the movable lens frame, and the second engaging portion of the second fixed lens frame, respectively.

[0063] (Composition 6) The lens barrel according to configuration 4 or 5, characterized in that the second guide bar engages with the first hole of the first fixed lens frame, the support portion of the movable lens frame, and the second hole of the second fixed lens frame, respectively.

[0064] (Composition 7) The lens barrel according to configuration 6, characterized in that the support portion includes a third hole and a fourth hole that engage with the second guide bar, and an opening formed between the third hole and the fourth hole.

[0065] (Composition 8) The lens barrel according to any one of configurations 1 to 7, characterized in that the portion that engages with the plurality of guide bars provided on the movable lens frame protrudes from an opening provided on the cylindrical portion of the second fixed lens frame.

[0066] (Composition 9) The movable lens frame is positioned inside the cylindrical portion of the second fixed lens frame. The lens barrel according to configuration 1, wherein the movable lens frame has a first projection and a second projection that protrude outwards, the first projection protrudes from a first opening provided in the cylindrical portion, and the second projection protrudes from a second opening provided in the cylindrical portion.

[0067] (Composition 10) The guide bar includes a first guide bar and a second guide bar positioned differently from the first guide bar. The lens barrel according to configuration 9, characterized in that the first protrusion is provided with a second engaging portion that engages with the first guide bar, and the second protrusion is provided with a support portion that engages with the second guide bar.

[0068] (Composition 11) It has a housing that holds the guide bar, The lens barrel according to any one of configurations 1 to 10, wherein the first fixed lens frame and the second fixed lens frame are held in the housing via fastening members.

[0069] (Composition 12) A lens barrel according to any one of configurations 1 to 11, characterized in that the diameter of the first lens is smaller than the diameter of the second lens.

[0070] (Composition 13) Image sensor and A lens barrel as described in any one of configurations 1 to 12, An imaging device characterized by the following features. [Explanation of Symbols]

[0071] 26. First fixed lens frame 28 Guide Bars 29 Guide Bars 30 Focus Movement Frames 31. Second fixed lens frame

Claims

1. A first fixed lens frame that holds the first lens, A second fixed lens frame that holds the second lens, A movable lens frame that moves along the optical axis of the lens between the first fixed lens frame and the second fixed lens frame, The movable lens frame is supported by a guide bar that allows it to move along the optical axis, The first fixed lens frame and the second fixed lens frame are positioned perpendicular to the optical axis via the guide bar, and are also positioned along the optical axis by the contact portion of the second fixed lens frame contacting the first fixed lens frame. A lens barrel characterized by the following features.

2. The lens barrel according to claim 1, characterized in that the movable lens frame is arranged inside the second fixed lens frame.

3. The lens barrel according to claim 1, characterized in that the guide bar engages with the respective engaging portions of the first fixed lens frame, the movable lens frame, and the second fixed lens frame, thereby passing between each lens frame, including the first fixed lens frame, the second fixed lens frame, and the movable lens frame.

4. The lens barrel according to claim 1, characterized in that the guide bar includes a first guide bar and a second guide bar positioned differently from the first guide bar.

5. The lens barrel according to claim 4, characterized in that the first guide bar engages with a first engaging portion of the first fixed lens frame, a third engaging portion of the movable lens frame, and a second engaging portion of the second fixed lens frame, respectively.

6. The lens barrel according to claim 4, characterized in that the second guide bar engages with the first hole of the first fixed lens frame, the support portion of the movable lens frame, and the second hole of the second fixed lens frame, respectively.

7. The lens barrel according to claim 6, characterized in that the support portion includes a third hole and a fourth hole that engage with the second guide bar, and an opening formed between the third hole and the fourth hole.

8. The lens barrel according to claim 1, characterized in that the portion that engages with the plurality of guide bars provided on the movable lens frame protrudes from an opening provided on the cylindrical portion of the second fixed lens frame.

9. The movable lens frame is positioned inside the cylindrical portion of the second fixed lens frame. The lens barrel according to claim 1, wherein the movable lens frame has a first projection and a second projection that protrude outwards, the first projection protrudes from a first opening provided in the cylindrical portion, and the second projection protrudes from a second opening provided in the cylindrical portion.

10. The guide bar includes a first guide bar and a second guide bar positioned differently from the first guide bar. The lens barrel according to claim 9, characterized in that the first projection is provided with a second engagement portion that engages with the first guide bar, and the second projection is provided with a support portion that engages with the second guide bar.

11. It has a housing that holds the guide bar, The lens barrel according to claim 1, wherein the first fixed lens frame and the second fixed lens frame are held in the housing via fastening members.

12. The lens barrel according to claim 1, characterized in that the diameter of the first lens is smaller than the diameter of the second lens.

13. Image sensor and A lens barrel according to any one of claims 1 to 12, An imaging device characterized by the following features.

Images