A small-bore lens focusing device

Abstract

The utility model provides a kind of small-bore lens focusing device, belong to optical focusing technical field.Device includes base, screw rod motor, lens moving assembly and lens fixed assembly;Lens moving assembly includes nut assembly, first lens support, first lens, guide rail and slider;Lens fixed assembly includes second lens support and second lens;Screw rod motor drives nut assembly to move along screw rod output shaft, slider is slid along guide rail, make first lens move focusing, and first lens and second lens optical axis coaxial.Through the high accuracy and stability of screw rod transmission, avoid the problem of traditional cam focusing mechanism, focusing feed quantity is stable, compact structure, without cam and gear, suitable for small-bore lens focusing.

Description

Technical Field

[0001] This utility model belongs to the field of optical focusing technology, and in particular relates to a focusing device for small-diameter lenses. Background Technology

[0002] In transmission optical systems, to accommodate different focal lengths or compensate for high and low temperatures, one or more lenses are typically required to shift along the optical axis. The key to this lies in the focusing mechanism, making it a crucial component of the optical system. The focusing mechanism must maintain the coaxiality and straightness of the focusing lens group's optical axis with the system's optical axis during translational movement, while also ensuring the precision of the translational motion.

[0003] In transmission optics systems, a common type of focusing mechanism is the cam focusing mechanism. The cam groove is generally driven by the meshing of two gears. The cam cannot rotate continuously, which usually requires two electrical limit switches or a motor to block the two ends of the marked position. However, existing cam focusing mechanisms generally have a backlash, require strict machining precision, have unstable focusing feed, and are relatively large in size due to the need to add cams and gears, making them unsuitable for focusing small-diameter lenses. Utility Model Content

[0004] This invention provides a focusing device for small-diameter lenses, which has a stable focusing feed and does not require the addition of cams and gears, making it suitable for focusing small-diameter lenses.

[0005] This utility model provides a focusing device for small-diameter lenses, including a base, a lead screw motor, a lens moving assembly, and a lens fixing assembly; The lead screw motor is fixedly connected to the base; The lens moving assembly includes a nut assembly, a first lens holder, a first lens, a guide rail, and a slider that matches the guide rail; The nut assembly is threadedly connected to the lead screw output shaft of the lead screw motor; the nut assembly is fixedly connected to the slider; the guide rail is fixedly connected to the base; the slider is fixedly connected to the first lens holder; the first lens is fixedly connected to the first lens holder. The lens fixing assembly includes a second lens holder and a second lens fixedly connected to the second lens holder; The second lens holder is fixedly connected to the base; the optical axis of the first lens and the optical axis of the second lens are on the same straight line.

[0006] Optionally, the lens moving assembly further includes a guide rail support; the guide rail support is fixedly connected to the guide rail and the base.

[0007] Optionally, the nut assembly includes a first nut, a compression spring, and a second nut; The first nut and the second nut are both threadedly connected to the lead screw output shaft; the compression spring is located on the lead screw output shaft, and its two ends abut against the first nut and the second nut respectively.

[0008] Optionally, the first nut has a first semi-circular protrusion on the side near the second nut; The second nut has a second semi-circular protrusion on the side closest to the first nut; The two ends of the first semicircular protrusion along the circumference of the lead screw output shaft respectively abut against the two ends of the second semicircular protrusion along the circumference of the lead screw output shaft; The first semicircular protrusion and the second semicircular protrusion are located inside or outside the compression spring.

[0009] Optionally, the first nut is provided with a third protrusion and a fourth protrusion on the side near the second nut; The second nut has a fifth protrusion and a sixth protrusion on the side near the first nut; The third protrusion abuts against the fifth protrusion along the circumference of the lead screw output shaft; the fourth protrusion abuts against the sixth protrusion along the circumference of the lead screw output shaft; The third, fourth, fifth, and sixth protrusions are all located inside or outside the compression spring.

[0010] Optionally, the small-diameter lens focusing device further includes a limiting component; The limiting component includes a photoelectric sensor and a first photoelectric limiting baffle; The photoelectric sensor is located on the base; the first photoelectric limiting baffle is fixedly connected to the first lens bracket; The first photoelectric limiting baffle is provided with a rectangular through hole; the light emitted by the photoelectric sensor can pass through the rectangular through hole.

[0011] Optionally, a first waist-shaped through hole is provided on the first photoelectric limiting baffle; a bolt for threaded connection of the first lens bracket is inserted into the first waist-shaped through hole.

[0012] Optionally, the first photoelectric limiting baffle is provided with a plurality of first waist-shaped through holes; each first waist-shaped through hole is provided with a bolt threaded to connect the first lens bracket; each bolt is in the same position in the corresponding first waist-shaped through hole.

[0013] Optionally, the limiting component further includes a second photoelectric limiting baffle for covering part of the rectangular through hole along the axial direction of the lead screw output shaft; A second waist-shaped through hole is provided on the second photoelectric limiting baffle at a position corresponding to the first waist-shaped through hole; a bolt threaded to connect the first lens bracket is passed through the first waist-shaped through hole and the second waist-shaped through hole.

[0014] Optionally, the limiting component further includes a second photoelectric limiting baffle for covering part of the rectangular through hole along the axial direction of the lead screw output shaft; The second photoelectric limiting baffle has multiple second waist-shaped through holes at positions corresponding to the multiple first waist-shaped through holes; each first waist-shaped through hole and each second waist-shaped through hole has a bolt threaded to connect to the first lens bracket; each bolt is in the same position in the corresponding first waist-shaped through hole and each second waist-shaped through hole.

[0015] This invention provides a focusing device for small-diameter lenses. A lead screw motor drives the lens moving assembly, utilizing the high precision and stability of lead screw transmission to avoid the backlash problem of traditional cam-based focusing mechanisms. The focusing feed is stable and does not require stringent machining precision. Furthermore, the small-diameter lens focusing device provided by this invention has a compact structure, eliminating the need for cams and gears, thus reducing the overall size and making it suitable for focusing small-diameter lenses. The cooperation of the guide rail and slider ensures the straightness of the first lens movement and its coaxiality with the second lens, improving focusing accuracy. The setting of the limiting component further ensures accurate control of the focusing range, enhancing the reliability and adaptability of the small-diameter lens focusing device provided by this invention. Attached Figure Description

[0016] To more clearly illustrate the technical solution of this utility model, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a small-diameter lens focusing device provided for an embodiment of this utility model; Figure 2 An exploded view of the structure of a small-diameter lens focusing device provided for an embodiment of this utility model; Figure 3 This is an exploded view of the nut assembly provided in an embodiment of the present utility model; Figure 4 This is a schematic diagram showing the positional relationship of the protrusions in the nut assembly provided in this embodiment of the utility model; Figure 5 A schematic diagram of the structure of two limiting baffles provided in an embodiment of this utility model; Figure 6This is another structural schematic diagram of the two limiting baffles provided in an embodiment of the present utility model.

[0018] The components include: 1. Base; 2. Lead screw motor; 21. Lead screw output shaft; 3. Lens moving assembly; 31. Nut assembly; 311. First nut; 3111. First semi-circular protrusion; 3112. Third protrusion; 3113. Fourth protrusion; 312. Compression spring; 313. Second nut; 3131. Second semi-circular protrusion; 3132. Fifth protrusion; 3133. Sixth protrusion; 32. First lens holder; 33. First lens; 34. Guide rail; 35. Slider; 36. Guide rail support; 4. Lens fixing assembly; 41. Second lens holder; 42. Second lens; 5. Limiting assembly; 51. Photoelectric sensor; 52. First photoelectric limiting baffle; 521. Rectangular through hole; 522. First waist-shaped through hole; 53. Second photoelectric limiting baffle; 531. Second waist-shaped through hole. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] This embodiment provides a focusing device for small-diameter lenses, such as... Figure 1 As shown, it includes a base 1, a lead screw motor 2, a lens moving assembly 3, and a lens fixing assembly 4.

[0021] The lead screw motor 2 is fixedly connected to the base 1.

[0022] like Figure 2 As shown, the lens moving assembly 3 includes a nut assembly 31, a first lens holder 32, a first lens 33, a guide rail 34, and a slider 35 that matches the guide rail 34.

[0023] Nut assembly 31 is threadedly connected to the lead screw output shaft 21 of lead screw motor 2; nut assembly 31 is fixedly connected to slider 35; guide rail 34 is fixedly connected to base 1; after the lead screw motor 2 is powered on, the lead screw output shaft 21 can rotate. In the prior art, lead screw motor 2 can be electrically connected to host computer, and the host computer controls the number of rotations and rotation direction of lead screw output shaft 21.

[0024] like Figure 2As shown, exemplarily, the two guide rails 34 are symmetrically arranged, and the slider 35 is provided with two through holes, which are respectively sleeved on the two guide rails 34, so that the slider 35 moves only along the axial direction of the guide rails 34; the cooperation between the guide rails 34 and the slider 35 makes the nut assembly 31 not rotate in the circumferential direction of the lead screw output shaft 21, that is, while the lead screw output shaft 21 rotates, the nut assembly 31 moves only along the axial direction of the lead screw output shaft 21.

[0025] The slider 35 is also provided with a through hole for the lead screw output shaft 21 to pass through, so as to prevent the lead screw output shaft 21 from obstructing the slider 35 from reciprocating on the guide rail 34.

[0026] Slider 35 is fixedly connected to the first lens holder 32; first lens 33 is fixedly connected to the first lens holder 32. For example... Figure 2 As shown, a through hole is provided on the first lens holder 32, and the first lens 33 is installed in the through hole provided on the first lens holder 32, and moves synchronously with the slider 35 along the axial direction (reciprocating) of the lead screw output shaft 21.

[0027] The lens fixing assembly 4 includes a second lens holder 41 and a second lens 42 fixedly connected to the second lens holder 41. Similarly, the second lens holder 41 has a through hole, and the second lens 42 is installed in the through hole in the second lens holder 41.

[0028] The second lens holder 41 is fixedly connected to the base 1; the optical axis of the first lens 33 and the optical axis of the second lens 42 are on the same straight line.

[0029] This embodiment provides a focusing device for small-diameter lenses. A lead screw motor 2 drives the lens moving assembly 3, utilizing the high precision and stability of lead screw transmission to avoid the backlash problem of traditional cam-based focusing mechanisms. The focusing feed is stable and does not require stringent machining precision. Furthermore, the small-diameter lens focusing device provided in this embodiment has a compact structure, eliminating the need for cams and gears, thus reducing the overall size and making it suitable for focusing small-diameter lenses. The cooperation between the guide rail 34 and the slider 35 ensures the straightness of the movement of the first lens 33 and its coaxiality with the second lens 42, improving focusing accuracy.

[0030] For example, such as Figure 2 As shown, the lens moving assembly 3 also includes a guide rail support 36; the guide rail support 36 is fixedly connected to the guide rail 34 and the base 1. The guide rail support 36 is fixedly connected to one end of the two guide rails 34 away from the lead screw motor 2; the guide rail support 36 is fixedly connected to the base 1, restricting the axial and radial movement of the guide rail support 36 on the lead screw output shaft 21, thereby limiting the movement of the slider 35 on the guide rail 34.

[0031] The guide rail support 36 is provided with a through hole for the lead screw output shaft 21 to pass through, so as to accommodate lead screw motors 2 with lead screw output shafts 21 of different lengths.

[0032] For example, such as Figure 3 As shown, the nut assembly 31 includes a first nut 311, a compression spring 312, and a second nut 313; both the first nut 311 and the second nut 313 are threadedly connected to the lead screw output shaft 21; the compression spring 312 is located on the lead screw output shaft 21, and its two ends abut against the first nut 311 and the second nut 313 respectively.

[0033] During operation, the compression spring 312 is in a compressed state with the first nut 311 and the second nut 313. The tension of the compression spring 312 causes the first nut 311 to be tightly attached to the right tooth surface of the lead screw output shaft 21, and the second nut 313 to be tightly attached to the left tooth surface of the lead screw output shaft 21, thereby eliminating the gap between the first nut 311 and the second nut 313 and the lead screw output shaft 21, so as to improve the stability of the focusing feed.

[0034] For example, such as Figure 3 As shown, the first nut 311 has a first semi-circular protrusion 3111 on the side near the second nut 313; the second nut 313 has a second semi-circular protrusion 3131 on the side near the first nut 311; the two ends of the first semi-circular protrusion 3111 abut against the two ends of the second semi-circular protrusion 3131 on the circumference of the lead screw output shaft 21; the first semi-circular protrusion 3111 and the second semi-circular protrusion 3131 are located inside or outside the compression spring 312.

[0035] Taking the first semicircular protrusion 3111 and the second semicircular protrusion 3131 located inside the compression spring 312 as an example, Figure 3 As shown, the first nut 311 is fixedly connected to the slider 35, and the second nut 313 is screwed to the lead screw output shaft 21 only, in addition to abutting against the compression spring 312. During operation, the first semi-circular protrusion 3111 and the second semi-circular protrusion 3131 form a circular protrusion. When the first nut 311 does not move, it restricts the rotation of the second nut 313 in the circumferential direction of the lead screw output shaft 21, thereby preventing the second nut 313 from moving in the axial direction of the lead screw output shaft 21 (that is, the first semi-circular protrusion 3111 and the second semi-circular protrusion 3131 cooperate with each other to make the feed amount of the first nut 311 and the second nut 313 equal), and always keeps the compression spring 312 in a compressed state.

[0036] For example, the cross-section of the first semicircular protrusion 3111 and the second semicircular protrusion 3131 does not have to be semicircular, as long as the first semicircular protrusion 3111 and the second semicircular protrusion 3131 form a circular protrusion.

[0037] For example, such as Figure 4As shown, the first nut 311 has a third protrusion 3112 and a fourth protrusion 3113 on the side near the second nut 313.

[0038] In this embodiment, it can be understood that the first semi-circular protrusion 3111 only retains the protrusions at both ends, namely the third protrusion 3112 and the fourth protrusion 3113.

[0039] The second nut 313 has a fifth protrusion 3132 and a sixth protrusion 3133 on the side near the first nut 311.

[0040] In this embodiment, it can be understood that the second semicircular protrusion 3131 only retains the protrusions at both ends, namely the fifth protrusion 3132 and the sixth protrusion 3133.

[0041] The third protrusion 3112 abuts against the fifth protrusion 3132 along the circumference of the lead screw output shaft 21; the fourth protrusion 3113 abuts against the sixth protrusion 3133 along the circumference of the lead screw output shaft 21.

[0042] The third protrusion 3112, the fourth protrusion 3113, the fifth protrusion 3132 and the sixth protrusion 3133 are all located inside or outside the compression spring 312.

[0043] During operation, it also serves to restrict the rotation of the second nut 313 around the lead screw output shaft 21 when the first nut 311 is not moving, thereby preventing the second nut 313 from moving axially on the lead screw output shaft 21 (that is, the first semicircular protrusion 3111 and the second semicircular protrusion 3131 cooperate with each other to make the feed amount of the first nut 311 and the second nut 313 equal), and always keep the compression spring 312 in a compressed state.

[0044] For example, such as Figure 1 As shown, the small-diameter lens focusing device provided in this embodiment also includes a limiting component 5.

[0045] like Figure 2 As shown, the limiting component 5 includes a photoelectric sensor 51 and a first photoelectric limiting baffle 52; in this embodiment, the photoelectric sensor 51 is a slot-type photoelectric sensor, that is, the emitter and receiver are installed on both sides of a slot, and when an object passes through, it blocks the light and triggers a signal.

[0046] The photoelectric sensor 51 is located on the base 1; the first photoelectric limiting baffle 52 is fixedly connected to the first lens bracket 32; the first photoelectric limiting baffle 52 is provided with a rectangular through hole 521; the light emitted by the photoelectric sensor 51 can pass through the rectangular through hole 521.

[0047] The photoelectric sensor 51 is electrically connected to the host computer. When the light emitted by the light emitter of the photoelectric sensor 51 can pass through the rectangular through hole 521, the host computer can control the lead screw motor 2 to rotate, thereby driving the first lens holder 32 and the first photoelectric limit baffle 52 to move until the first photoelectric limit baffle 52 blocks the light, triggering a signal and transmitting it to the host computer. The host computer responds to the trigger signal and controls the lead screw motor 2 to stop rotating, thereby limiting the first lens holder 32 through the first photoelectric limit baffle 52.

[0048] For example, such as Figure 5 As shown, a first waist-shaped through hole 522 is provided on the first photoelectric limiting baffle 52; a bolt for threaded connection of the first lens bracket 32 ​​is inserted into the first waist-shaped through hole 522.

[0049] Loosening the bolts allows the first photoelectric limiting baffle 52 to move, moving it closer to or further away from the lead screw motor 2. This, in turn, causes the rectangular through hole 521 to move closer to or further away from the lead screw motor 2. During the movement of the rectangular through hole 521, the movement only occurs along its length. After the first photoelectric limiting baffle 52 reaches the target position, the bolts are tightened to control the focusing range of the first lens 33. The length of the rectangular through hole 521 is taken as the first distance, and the focusing range of the first lens 33 is the interval formed by the focal length before the first lens 33 moves the first distance and the focal length after the first distance.

[0050] To prevent the rectangular through-hole 521 from moving in its width direction, for example, as follows Figure 6 As shown, the first photoelectric limiting baffle 52 has multiple first waist-shaped through holes 522; each first waist-shaped through hole 522 has a bolt threadedly connected to the first lens bracket 32; each bolt is in the same position in the corresponding first waist-shaped through hole 522.

[0051] When the length of the first oblong through-hole 522 does not meet the focusing range of the first lens 33, for example, as follows: Figure 5 and Figure 6 As shown, the limiting component 5 also includes a second photoelectric limiting baffle 53, which is used to cover part of the rectangular through hole 521 along the length direction of the rectangular through hole 521 (during which the rectangular through hole 521 is fully covered in the width direction) to control the length of the rectangular through hole 521, thereby controlling the focusing range of the first lens 33.

[0052] The second photoelectric limiting baffle 53 has a second waist-shaped through hole 531 at a position corresponding to the first waist-shaped through hole 522; the first waist-shaped through hole 522 and the second waist-shaped through hole 531 are fitted with bolts for threaded connection of the first lens bracket 32.

[0053] Loosening the bolts allows both the first photoelectric limiting baffle 52 and the second photoelectric limiting baffle 53 to move. Similarly, the first photoelectric limiting baffle 52 and the second photoelectric limiting baffle 53 can only move in the length direction of the rectangular through hole 521. After moving the first photoelectric limiting baffle 52 and the second photoelectric limiting baffle 53 to the target position, tighten the bolts to control the focusing range of the first lens 33.

[0054] Similarly, in order to prevent the rectangular through hole 521 from moving in its width direction, for example, a plurality of second waist-shaped through holes 531 are provided on the second photoelectric limiting baffle 53 at positions corresponding to the plurality of first waist-shaped through holes 522; a bolt for threaded connection of the first lens bracket 32 ​​is passed through each first waist-shaped through hole 522 and the second waist-shaped through hole 531; the position of each bolt in the corresponding first waist-shaped through hole 522 and the second waist-shaped through hole 531 is the same.

[0055] In summary, this embodiment provides a focusing device for small-diameter lenses. The lens moving component 3 is driven by a lead screw motor 2. By utilizing the high precision and stability of the lead screw transmission itself, the backlash problem existing in traditional cam focusing mechanisms is effectively avoided, and the focusing feed amount is stable and controllable. It also has lower requirements for the machining precision of parts, reducing manufacturing costs. The structure is compact, eliminating complex transmission components such as cams and gears, and the overall size is optimized. It is especially suitable for focusing scenarios of small-diameter lenses.

[0056] Through the precise cooperation between the guide rail 34 and the slider 35, and the structure of the nut assembly 31 using a combination of compression spring 312 and double nuts, supplemented by a circumferential limiting design with semi-circular protrusions or multi-point protrusions, the backlash in the lead screw drive is effectively eliminated, further improving the straightness of the movement of the first lens 33 and its coaxiality with the second lens 42, thereby ensuring high precision and repeatability of the entire focusing process.

[0057] In addition, the limiting component 5, which integrates a photoelectric sensor and an adjustable photoelectric limiting baffle, can flexibly adjust the position of the baffle through the waist-shaped through hole. This allows for precise setting and adjustment of the movement range of the first lens 33, enhancing the adaptability and controllability of the device and improving the reliability and safety of the equipment operation.

[0058] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation methods of the present invention without departing from the spirit and scope of the present invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A focusing device for small-diameter lenses, characterized in that, It includes a base (1), a lead screw motor (2), a lens moving assembly (3), and a lens fixing assembly (4); The lead screw motor (2) is fixedly connected to the base (1); The lens moving assembly (3) includes a nut assembly (31), a first lens holder (32), a first lens (33), a guide rail (34), and a slider (35) that matches the guide rail (34). The nut assembly (31) is threadedly connected to the lead screw output shaft (21) of the lead screw motor (2); the nut assembly (31) is fixedly connected to the slider (35); the guide rail (34) is fixedly connected to the base (1); the slider (35) is fixedly connected to the first lens holder (32); the first lens (33) is fixedly connected to the first lens holder (32); The lens fixing assembly (4) includes a second lens holder (41) and a second lens (42) fixedly connected to the second lens holder (41). The second lens holder (41) is fixedly connected to the base (1); the optical axis of the first lens (33) and the optical axis of the second lens (42) are on the same straight line.

2. The focusing device for small-diameter lenses according to claim 1, characterized in that, The lens moving assembly (3) also includes a guide rail support (36); the guide rail support (36) is fixedly connected to the guide rail (34) and the base (1).

3. The focusing device for small-diameter lenses according to claim 1, characterized in that, The nut assembly (31) includes a first nut (311), a compression spring (312), and a second nut (313); The first nut (311) and the second nut (313) are both threadedly connected to the lead screw output shaft (21); the compression spring (312) is located on the lead screw output shaft (21), and its two ends abut against the first nut (311) and the second nut (313) respectively.

4. The small-diameter lens focusing device according to claim 3, characterized in that, The first nut (311) has a first semi-circular protrusion (3111) on the side near the second nut (313). The second nut (313) has a second semi-circular protrusion (3131) on the side near the first nut (311). The first semicircular protrusion (3111) abuts against the second semicircular protrusion (3131) at both ends of the lead screw output shaft (21) along the circumference of the lead screw output shaft (21); The first semicircular protrusion (3111) and the second semicircular protrusion (3131) are located inside or outside the compression spring (312).

5. The small-diameter lens focusing device according to claim 3, characterized in that, The first nut (311) has a third protrusion (3112) and a fourth protrusion (3113) on the side near the second nut (313). The second nut (313) has a fifth protrusion (3132) and a sixth protrusion (3133) on the side near the first nut (311). The third protrusion (3112) abuts against the fifth protrusion (3132) circumferentially along the lead screw output shaft (21); the fourth protrusion (3113) abuts against the sixth protrusion (3133) circumferentially along the lead screw output shaft (21). The third protrusion (3112), the fourth protrusion (3113), the fifth protrusion (3132) and the sixth protrusion (3133) are all located inside or outside the compression spring (312).

6. The focusing device for small-diameter lenses according to claim 1, characterized in that, It also includes a limiting component (5); The limiting component (5) includes a photoelectric sensor (51) and a first photoelectric limiting baffle (52). The photoelectric sensor (51) is located on the base (1); the first photoelectric limiting baffle (52) is fixedly connected to the first lens bracket (32). The first photoelectric limiting baffle (52) is provided with a rectangular through hole (521); the light emitted by the photoelectric sensor (51) can pass through the rectangular through hole (521).

7. The focusing device for small-diameter lenses according to claim 6, characterized in that, The first photoelectric limiting baffle (52) has a first waist-shaped through hole (522); a bolt threaded to connect the first lens bracket (32) is inserted in the first waist-shaped through hole (522).

8. The focusing device for small-diameter lenses according to claim 6, characterized in that, The first photoelectric limiting baffle (52) has multiple first waist-shaped through holes (522); each first waist-shaped through hole (522) has a bolt threadedly connected to the first lens bracket (32); each bolt is in the same position in the corresponding first waist-shaped through hole (522).

9. The focusing device for small-diameter lenses according to claim 7, characterized in that, The limiting component (5) also includes a second photoelectric limiting baffle (53) for covering part of the rectangular through hole (521) along the axial direction of the lead screw output shaft (21). The second photoelectric limiting baffle (53) has a second waist-shaped through hole (531) at the position corresponding to the first waist-shaped through hole (522); the first waist-shaped through hole (522) and the second waist-shaped through hole (531) are fitted with bolts threaded to connect the first lens bracket (32).

10. The focusing device for a small-diameter lens according to claim 8, characterized in that, The limiting component (5) also includes a second photoelectric limiting baffle (53) for covering part of the rectangular through hole (521) along the axial direction of the lead screw output shaft (21). The second photoelectric limiting baffle (53) has multiple second waist-shaped through holes (531) at positions corresponding to the multiple first waist-shaped through holes (522); each first waist-shaped through hole (522) and second waist-shaped through hole (531) is provided with a bolt threaded to connect the first lens bracket (32); each bolt is in the same position in the corresponding first waist-shaped through hole (522) and second waist-shaped through hole (531).

Images