Lens barrel, telecentric lens and camera module

Abstract

The embodiment of the utility model relates to the technical field of telecentric lenses, and provides a lens barrel, a telecentric lens and a camera module, the lens barrel of the telecentric lens comprises a first lens barrel, a second lens barrel and a third lens barrel which are arranged from an object side to an image side; the first lens barrel comprises a first channel and a second channel which are arranged from the object side to the image side, the axis of the second channel is perpendicular to the axis of the first channel, and the second channel and the first channel are communicated at the intersection point to form an L-shaped connection structure; the second lens cone is connected with a first switching assembly and a coaxial light source, and the coaxial light source is used for providing a light source for the interior of the second lens cone; one end of the second lens cone is connected with the second channel of the first lens cone, the other end of the second lens cone is rotatably connected with the third lens cone through a first switching assembly, the axis of the first channel is perpendicular to the axis of the second lens cone, and the axis of the second channel, the axis of the second lens cone and the axis of the third lens cone are parallel in pairs; the second lens cone is connected with a coaxial light source, and the optical axis of the coaxial light source is perpendicular to the axis of the second lens cone.

Description

Technical Field

[0001] This application relates to the field of telecentric lens technology, and in particular to a lens barrel, a telecentric lens, and a camera module. Background Technology

[0002] Machine vision inspection technology is widely used in all aspects of manufacturing. It plays a crucial role in the inspection of appearance defects in numerous industries, such as circuit boards, semiconductor chips, display panels, and food packaging. With the continuous improvement of industrial intelligence, the requirements for the accuracy of product defect detection are becoming increasingly stringent. Telecentric lenses are typically used to perform high-precision dimensional measurements or inspections of products.

[0003] In related technologies, telecentric lenses have a straight barrel, meaning the object plane and image plane are parallel. When installing a telecentric lens, sufficient space needs to be reserved, making it impossible to place it in a corner. At the same time, in order to improve the imaging effect, a coaxial light source is usually added. While this improves the imaging quality of the telecentric lens, it also increases the overall size of the telecentric lens with a coaxial light source, requiring more space for placement. Furthermore, the coaxial light source is relatively fixed relative to the telecentric lens barrel, limiting its installation. Utility Model Content

[0004] The embodiments of this application provide a lens barrel, a telecentric lens, and a camera module to solve the problem that telecentric lenses in related technologies have high requirements for the dimensionality of the arrangement space in the length direction, which limits their application scenarios.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] In a first aspect, embodiments of this application provide a telecentric lens barrel, the lens barrel comprising a first lens barrel, a second lens barrel, and a third lens barrel arranged from the object side to the image side; the first lens barrel includes a first channel and a second channel arranged from the object side to the image side, the axis of the second channel being perpendicular to the axis of the first channel and connecting at the intersection in an L-shaped connection structure; a first adapter assembly and a coaxial light source are connected to the second lens barrel, the coaxial light source being used to provide light to the interior of the second lens barrel; one end of the second lens barrel is connected to the second channel of the first lens barrel, and the other end of the second lens barrel is rotatably connected to the third lens barrel via the first adapter assembly, the axis of the first channel being perpendicular to the axis of the second lens barrel, and the axes of the second channel, the second lens barrel, and the third lens barrel being parallel to each other; a coaxial light source is connected to the second lens barrel, the optical axis of the coaxial light source being perpendicular to the axis of the second lens barrel.

[0007] In some embodiments, a second adapter is connected to the end of the second lens barrel away from the first adapter, and the first lens barrel and the second lens barrel are rotatably connected through the second adapter.

[0008] In some embodiments, the first adapter assembly includes a first connecting cylinder, a second connecting cylinder, and a first fastener. The first connecting cylinder is screwed to the third lens barrel, the second connecting cylinder is screwed to the second lens barrel, the first connecting cylinder and the second connecting cylinder are engaged, and the first fastener is used to prevent the second lens barrel and the third lens barrel from rotating relative to each other.

[0009] In some embodiments, the first connecting tube includes a first tube segment, a second tube segment, and a third tube segment arranged from the object side to the image side, the third tube segment being connected to the third lens barrel, the inner diameter of the first tube segment being smaller than the inner diameter of the second tube segment, and the inner diameter of the third tube segment being smaller than the inner diameter of the second tube segment; the second connecting tube includes a first tube body and a second tube body arranged from the object side to the image side, the first tube body being connected to the second lens barrel, the outer diameter of the second tube body being larger than the outer diameter of the first tube body, the outer diameter of the second tube body being larger than the inner diameter of the second tube segment, and the outer diameter of the first tube body being smaller than the inner diameter of the second tube segment.

[0010] In some embodiments, the second lens barrel has a first clearance section at the end near the image side, the outer diameter of the first clearance section is smaller than the inner diameter of the first barrel section, the first clearance section is provided with a clearance groove, the clearance groove extends circumferentially along the first connecting barrel; the first barrel section is provided with a through hole, the through hole penetrates the first barrel section radially along the first connecting barrel, the first fastener is screwed to the through hole and can pass through the through hole and abut against the groove wall of the clearance groove.

[0011] In some embodiments, the length of the first clearance section is less than or equal to the length of the first tube section in the axial direction of the second lens barrel.

[0012] In some embodiments, the sidewall of the clearance groove near the third lens barrel is inclined relative to the axis of the second lens barrel.

[0013] In some embodiments, the end of the second lens barrel away from the first adapter assembly is connected to a second adapter assembly, and the first lens barrel and the second lens barrel are rotatably connected through the second adapter assembly; the second adapter assembly includes a third connecting cylinder, a fourth connecting cylinder, and a second fastener, the third connecting cylinder being screwed to the first lens barrel, the fourth connecting cylinder being screwed to the second lens barrel, the third connecting cylinder being engaged with the fourth connecting cylinder, and the second fastener being used to prevent the first lens barrel and the second lens barrel from rotating relative to each other.

[0014] In some embodiments, the second lens barrel includes a second clearance section, a main body section, and a first clearance section arranged along the object side to the image side. The second clearance section is connected to the first lens barrel via a second adapter assembly. A light source mounting hole is provided on the side wall of the main body section, and the coaxial light source is connected to the light source mounting hole. The light source mounting hole penetrates one side wall of the main body section radially along the second lens barrel. The structure of the second clearance section is symmetrical to the structure of the first clearance section about the axis of the light source mounting hole.

[0015] In some embodiments, the optical axis of the coaxial light source is perpendicular to the axis of the second lens barrel, and a 45° beam splitter is provided inside the second lens barrel. The light emitted by the coaxial light source enters the interior of the second lens barrel through the 45° beam splitter.

[0016] The telecentric lens barrel provided in the embodiments of this application includes a first barrel, a second barrel, and a third barrel along the object side to the image side. That is, the entire barrel adopts a multi-segment structure. The first barrel includes a first channel and a second channel with mutually perpendicular axes, connected in an L-shape. Thus, when optical elements such as a first lens group and a reflector are arranged inside the first barrel, the optical axis of light entering from the first channel is deflected by 90° and exits from the second channel. Simultaneously, the axes of the second channel, the second barrel, and the third barrel are parallel to each other. Compared to a straight-barreled barrel structure, this barrel structure reduces the impact on the axial direction of the third barrel. The length of the lens is suitable for placement in corner spaces. When the lens group is arranged, the object plane and the image plane are perpendicular to each other. Secondly, the second lens barrel and the third lens barrel are rotatably connected through the first adapter assembly. That is to say, the second lens barrel and the third lens barrel form a rotating pair, which can rotate 360° around the axis parallel to the second lens barrel. Then, a coaxial light source is connected to the second lens barrel, so that when the second lens barrel and the second lens barrel rotate relative to each other, the relative position of the image plane and the coaxial light source can change. Thus, the telecentric lens can achieve the adjustment of the relative position between the coaxial light source and the image plane while ensuring that the image plane and the object plane are perpendicular, further reducing the limitation on the placement space of the telecentric lens.

[0017] Secondly, embodiments of this application provide a telecentric lens, including a lens barrel, a first lens group, and a second lens group as described in the first aspect, wherein the first lens group is disposed inside the first lens barrel of the lens barrel, and the second lens group is disposed inside the third lens barrel of the lens barrel.

[0018] The telecentric lens in this embodiment has the same structure and technical effect as the telecentric lens in the first aspect, and will not be described again here.

[0019] Thirdly, embodiments of this application provide a camera module, including a photosensitive element and the telecentric lens described in the first aspect, wherein the photosensitive element is disposed on the image side of the telecentric lens.

[0020] The telecentric lens in the camera module of this application embodiment has the same structure and technical effect as the telecentric lens in the second aspect, and will not be described again here. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the telecentric lens in the embodiments of this application;

[0022] Figure 2 for Figure 1 Cross-sectional view;

[0023] Figure 3 for Figure 2 A magnified view of point I;

[0024] Figure 4 A partially exploded view of the second lens barrel, the first adapter assembly, and the third lens barrel;

[0025] Figure 5 This is a partially exploded view of the first lens barrel, the second adapter assembly, and the second lens barrel.

[0026] The following are the labeling elements in the figure:

[0027] 1. First lens tube; 101. First channel; 102. Second channel; 11. First section; 12. Second section; 13. Adapter tube; 14. Reflector;

[0028] 2. Second lens barrel; 201. Clearance groove; 21. First clearance section; 22. Second clearance section; 23. Main body section; 230. Light source mounting hole;

[0029] 3. Third lens tube;

[0030] 4. First adapter assembly; 41. First connecting cylinder; 410. Through hole; 411. First cylinder section; 412. Second cylinder section; 413. Third cylinder section; 42. Second connecting cylinder; 421. First cylinder body; 422. Second cylinder body; 43. First fastener;

[0031] 5. Second adapter assembly; 51. Third connecting cylinder; 52. Fourth connecting cylinder; 53. Second fastener;

[0032] 6. Coaxial light source;

[0033] 7. Photosensitive element;

[0034] First lens group G1; Second lens group G2; First lens L1; Second lens L2; ​​Third lens L3; Fourth lens L4; Fifth lens L5; Sixth lens L6; 45° beam splitter L7. Detailed Implementation

[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0037] like Figure 1 , Figure 2 As shown, this application embodiment provides a camera module, including a telecentric lens and a photosensitive element 7, with the photosensitive element 7 located on the image side of the telecentric lens.

[0038] The working principle of the camera module is as follows: the light reflected from the subject passes through the telecentric lens to generate an optical image, which is then projected onto the photosensitive surface of the photosensitive element 7. The photosensitive element 7 converts the optical image into an electrical signal, i.e., an analog image signal, and transmits it to the processor.

[0039] The photosensitive element 7 (also known as an image sensor) is a semiconductor chip containing hundreds of thousands to millions of photodiodes on its surface. When illuminated by light, these photodiodes generate electrical charges. The photosensitive element 7 can be a charge-coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) device. A CCD is made of a highly sensitive semiconductor material that converts light into electrical charges. A charge-coupled device consists of many photosensitive units, typically measured in megapixels. When the surface of the photosensitive element 7 is illuminated, each photosensitive unit reflects a charge onto the component. The signals generated by all the photosensitive units are added together to form a complete image.

[0040] Among them, the telecentric lens is an optical lens mainly used in fields such as machine vision, precision measurement and inspection. The optical lens mainly uses the refraction principle of the lens to form an image, that is, the light of the scene passes through the optical lens and forms a clear image on the focal plane, and the image of the scene is recorded by the photosensitive element 7 located on the focal plane.

[0041] like Figure 2 and Figure 3 As shown, the telecentric lens includes a lens barrel and a first lens group and a second lens group.

[0042] The first lens group G1 and the second lens group G2 mentioned above constitute the imaging system of the telecentric lens. The following explanation will use an imaging system comprising the first lens group G1 and the second lens group G2 as an example. Figure 2 As shown in the figure, the first lens group G1 includes a first lens L1, a second lens L2, a third lens L3 and a fourth lens L1 arranged from the object side to the image side; the second lens group G2 includes a fifth lens L5 and a sixth lens L6 arranged from the object side to the image side.

[0043] like Figure 2 and Figure 3 As shown, the lens barrel includes a first lens barrel 1, a second lens barrel 2, and a third lens barrel 3 arranged from the object side to the image side. The first lens barrel 1 includes a first channel 101 and a second channel 102 arranged from the object side to the image side. The axis of the second channel 102 is perpendicular to the axis of the first channel 101 and they are connected at the intersection in an L-shaped connection structure. That is, the first channel 101 and the second channel 102 are connected in an L-shaped connection structure. The second lens barrel 2 is connected to a first adapter assembly 4 and a coaxial light source 6. The coaxial light source 6 is used to provide light to the interior of the second lens barrel 2. One end of the second lens barrel 2 is connected to the second channel 102 of the first lens barrel 1, and the other end of the second lens barrel 2 is rotatably connected to the third lens barrel 3 through the first adapter assembly 4. The axis of the first channel 101 is perpendicular to the axis of the second lens barrel 2, and the axes of the second channel 102, the second lens barrel 2, and the third lens barrel 3 are parallel to each other. The second lens barrel 2 is connected to a coaxial light source 6, and the optical axis of the coaxial light source 6 is perpendicular to the axis of the second lens barrel 2.

[0044] like Figure 2As shown, the first lens tube 1 includes a first section 11, a second section 12, and a connecting tube 13. The first section 11 and the second section 12 are connected by the connecting tube 13. The connecting tube 13 has two mutually arranged interfaces. One interface is connected to the first section 11 to form a first channel 101, and the other interface is connected to the second section 12 to form a second channel 102. A reflector 14 is provided inside the connecting tube 13. The reflector 14 has a reflective surface, and the center of the reflective surface refers to the geometric center of the reflective surface. The axis of the first channel 101 intersects the axis of the second channel perpendicularly, and the intersection is an L-shaped connection structure. The reflector 14 is set at the corner to deflect the optical axis of the first lens group G1 by 90° so that it is parallel to the optical axis of the second lens group G2.

[0045] The other end of the second lens tube 2 mentioned above ( Figure 2 The right end of the second lens barrel 2 is rotatably connected to the third lens barrel 3 via the first adapter assembly 4. This means that the axis of the second lens barrel 2 is parallel to the axis of the third lens barrel 3, and the second lens barrel 2 and the third lens barrel 3 can rotate relative to each other around the axis of the third lens barrel 3. Normally, the third lens barrel 3 is connected to the photosensitive element 7, so the third lens barrel 3 is fixed. When the second lens barrel 2 is installed, the second lens barrel 2 can rotate relative to the axis of the third lens barrel 3, and at the same time, it drives the coaxial light source 6 to rotate. That is, the coaxial light source 6 can rotate 360° relative to the third lens barrel 3 around the axis of the third lens barrel 3, adjusting the relative position angle between the coaxial light source 6 and the image plane of the photosensitive element 7.

[0046] The optical axis of the coaxial light source 6 is perpendicular to the axis of the second lens barrel 2, and the axis of the first channel 101 is perpendicular to the axis of the second lens barrel 2. Therefore, when the coaxial light source 6 is rotated until its optical axis is parallel to the axis of the first channel 101, the volume of the telecentric lens barrel is minimized. Of course, if there is sufficient space for the telecentric lens, the axis of the coaxial light source 6 can also be a straight line skewed from the axis of the first channel 101.

[0047] The telecentric lens barrel provided in the embodiments of this application includes a first barrel 1, a second barrel 2, and a third barrel 3 along the object side to the image side. That is, the entire barrel adopts a multi-segment structure. The first barrel 1 includes a first channel 101 and a second channel 102 with mutually perpendicular axes. The first channel 101 and the second channel 102 are connected in an L-shaped structure. Thus, when optical elements such as a first lens group and a reflector are arranged inside the first barrel 1, the optical axis of light entering from the first channel 101 is deflected by 90° and exits from the second channel 102. Simultaneously, the axes of the second channel 102, the second barrel 2, and the third barrel 3 are parallel to each other. Compared to a straight-barreled barrel structure, this barrel structure reduces the impact on the third... The length of the lens barrel 3 along its axial direction is suitable for placement in corner spaces. When the lens group is arranged, the object plane and the image plane are perpendicular to each other. Secondly, the second lens barrel 2 and the third lens barrel 3 are rotatably connected through the first adapter assembly 4. That is, a rotating pair is formed between the second lens barrel 2 and the third lens barrel 3, which can rotate 360° around the axis parallel to the second lens barrel 2. Then, a coaxial light source 6 is connected to the second lens barrel 2, so that when the second lens barrel 2 and the third lens barrel 3 rotate relative to each other, the relative position between the image plane and the coaxial light source 6 can change. Thus, the telecentric lens, while ensuring that the image plane and the object plane are perpendicular, also achieves the adjustment of the relative position between the coaxial light source 6 and the image plane, further reducing the limitation on the placement space of the telecentric lens.

[0048] like Figure 2 , Figure 3 and Figure 4 As shown, in some embodiments, the second lens barrel 2 includes a second clearance section 22, a main body section 23, and a first clearance section 21 arranged along the object side to the image side. The first clearance section 21 is connected to the third lens barrel 3 via a first adapter assembly 4, and the second clearance section 22 is connected to the first lens barrel 1 via a second adapter assembly 5. A light source mounting hole 230 is provided on the side wall of the main body section 23, and a coaxial light source 6 is connected to the light source mounting hole 230. The light source mounting hole 230 is radially ( Figure 3 The structure of the second clearance section 22 is symmetrical about the axis of the light source mounting hole 230 with respect to the vertical direction of the first clearance section 21.

[0049] Compared to the main body section 23, the first and second clearance sections 21 and 22 have smaller outer diameters, allowing for installation space at both ends of the second lens barrel 2 for connection with the first adapter assembly 4 and the second adapter assembly 5. This ensures that the components of the lens barrel are securely connected while making efficient use of the space in the second lens barrel 2, thus contributing to the miniaturization of the lens barrel. The main body section 23 refers to the section connected to the coaxial light source 6. Its relatively large outer diameter enhances the secure connection between the main body section 23 and the coaxial light source 6, thereby improving the overall reliability of the lens barrel.

[0050] The above configuration makes the structure of the second lens barrel 2 axially symmetrical, which simplifies the structure and processing steps of the second lens barrel 2, reduces processing costs, and facilitates assembly and connection with the first lens barrel 1 and the second lens barrel 2.

[0051] It should be noted that, in addition to being symmetrical about the axis of the light source mounting hole 230, the structure of the second clearance section 22 can also be different from that of the first clearance section 21. However, the difference here only includes differences in size. For example, the sizes of the second clearance section 22 and the first clearance section 21 may not be exactly the same. In this case, the structure of the first adapter assembly 4 needs to be adjusted according to the sizes of the second clearance section 22 and the first clearance section 21, but the outline and function of the structure will change.

[0052] like Figure 3 and Figure 4 As shown, one end of the second lens barrel 2 is rotatably connected to the third lens barrel 3 via the first adapter assembly 4, and the other end of the second lens barrel 2 away from the first adapter assembly 4 is connected to the second adapter assembly 5. The first lens barrel 1 and the second lens barrel 2 are rotatably connected via the second adapter assembly 5.

[0053] The first lens barrel 1 and the second lens barrel 2 are rotatably connected by the second adapter assembly 5. That is, the second lens barrel 2 and the first lens barrel 1 form a rotating pair, which can rotate 360° around the axis parallel to the second lens barrel 2.

[0054] With the above settings, not only can the first lens barrel 1 of the telecentric lens also rotate relative to the axis of the third lens barrel 3, but the relative position angle between the object plane and the image plane of the telecentric lens imaging system can also be adjusted on the basis of being perpendicular to the image plane, so as to adapt to the requirements of different placement spaces.

[0055] like Figure 3 and Figure 4 As shown, the first adapter assembly 4 includes a first connecting cylinder 41, a second connecting cylinder 42, and a first fastener 43. The first connecting cylinder 41 is screwed to the third lens barrel 3, the second connecting cylinder 42 is screwed to the second lens barrel 2, the first connecting cylinder 41 and the second connecting cylinder 42 are engaged, and the first fastener 43 is used to prevent the second lens barrel 2 and the third lens barrel 3 from rotating relative to each other.

[0056] With the above setup, after the first connecting cylinder 41 and the second connecting cylinder 42 are snapped together, and then screwed and fixed to the second lens barrel 2 and the third lens barrel 3 respectively, not only can the second connecting cylinder 42 drive the second lens barrel 2 to rotate relative to the first connecting cylinder 41 around the axis of the third lens barrel 3, thereby making the second lens barrel 2 and the third lens barrel 3 rotate relative to each other, but also, once the relative positions of the two are fixed, the second lens barrel 2, the third lens barrel 3, the first connecting cylinder 41 and the second connecting cylinder 42 can be fixed relative to each other by the first fastener 43.

[0057] like Figure 3 and Figure 4 As shown, the first connecting tube 41 includes a first tube segment 411, a second tube segment 412, and a third tube segment 413 arranged from the object side to the image side. The third tube segment 413 is connected to the third lens tube 3. The inner diameter of the first tube segment 411 is smaller than the inner diameter of the second tube segment 412, and the inner diameter of the third tube segment 413 is smaller than the inner diameter of the second tube segment 412. The second connecting tube 42 includes a first tube body 421 and a second tube body 422 arranged from the object side to the image side. The first tube body 421 is connected to the second lens tube 2. The outer diameter of the second tube body 422 is larger than the outer diameter of the first tube body 421, and the outer diameter of the second tube body 422 is larger than the inner diameter of the second tube segment 412. The outer diameter of the first tube body 421 is smaller than the inner diameter of the second tube segment 412.

[0058] With the above configuration, the first connecting cylinder 41 and the second connecting cylinder 42 can be sleeved together, and a notch is formed at the connection between the first cylinder body 421 and the second cylinder body 422. The second cylinder segment 412 is engaged with the notch. When there is a gap between the end face of the second cylinder segment 412 and the end face of the second cylinder body 422, the first connecting cylinder 41 and the second connecting cylinder 42 can rotate relative to each other. At least one of the first connecting cylinder 41 and the second connecting cylinder 42 moves along the axial direction of the second lens barrel 2 until the end face of the second cylinder segment 412 contacts the end face of the second cylinder body 422. At this point, the first connecting cylinder 41 and the second connecting cylinder 42 can be relatively fixed. They can only rotate relative to each other when the torque is greater than the friction force.

[0059] like Figure 3 and Figure 4 As shown, the outer diameter of the first clearance section 21 is smaller than the inner diameter of the first cylindrical section 411. The first clearance section 21 is provided with a clearance groove 201, which extends circumferentially along the first connecting cylinder 41. The first cylindrical section 411 is provided with a through hole 410, which penetrates the first cylindrical section 411 radially. The first fastener 43 is screwed to the through hole 410 and can pass through the through hole 410 to abut against the groove wall of the clearance groove 201.

[0060] With the above setup, after the first connecting cylinder 41 and the second connecting cylinder 42 are snapped together, and then screwed and fixed to the second lens barrel 2 and the third lens barrel 3 respectively, the first connecting cylinder 41 and the second connecting cylinder 42 are snapped together. There is a gap between the first connecting cylinder 41 and the second connecting cylinder 42, which allows them to rotate relative to each other. That is, the second connecting cylinder 42 drives the second lens barrel 2 to rotate relative to the first connecting cylinder 41 around the axis of the third lens barrel 3, thereby making the second lens barrel 2 and the third lens barrel 3 rotate relative to each other. When the first fastener 43 is screwed into the through hole 410 until it abuts against the groove wall of the relief groove 201, the relative rotation of the second lens barrel 2 and the third lens barrel 3 is restricted, so that the second lens barrel 2, the third lens barrel 3, the first connecting cylinder 41 and the second connecting cylinder 42 are fixed relative to each other.

[0061] like Figure 3 As shown, in the axial direction of the second lens tube 2, the length of the first clearance section 21 is less than or equal to the length of the first tube section 411.

[0062] With the above configuration, during the screw connection between the first connecting cylinder 41 and the third lens barrel 3, the first connecting cylinder 41 and the second connecting cylinder 42 can be fully contacted along the axial direction, which increases the friction between the first connecting cylinder 41 and the second connecting cylinder 42, thereby facilitating the tight connection between the second lens barrel 2 and the third lens barrel 3.

[0063] like Figure 3 and Figure 4 As shown, the sidewall of the clearance groove 201 near the third lens barrel 3 is inclined relative to the axis of the second lens barrel 2.

[0064] With the above settings, during the screwing process of the first fastener 43 and the through hole 410, a force is applied to the sidewall of the relief groove 201, causing the second lens barrel 2 to move along the axis towards the side closer to the third lens barrel 3, so that the first connecting cylinder 41 and the second connecting cylinder 42 contact each other along the axial surface, thereby making the connection between the second lens barrel 2 and the third lens barrel 3 more secure.

[0065] like Figure 3 , Figure 4 and Figure 5 As shown, the second adapter assembly 5 includes a third connecting cylinder 51, a fourth connecting cylinder 52, and a second fastener 53. The third connecting cylinder 51 is screwed to the first lens barrel 1, and the fourth connecting cylinder 52 is screwed to the second lens barrel 2. The third connecting cylinder 51 and the fourth connecting cylinder 52 are engaged. The second fastener 53 is used to prevent the first lens barrel 1 and the second lens barrel 2 from rotating relative to each other.

[0066] One assembly process for the second lens barrel 2, the first adapter assembly 4, and the third lens barrel 3 is as follows:

[0067] First, snap the first connecting cylinder 41 and the second connecting cylinder 42 together and screw them into the third lens barrel 3. Then, screw the second connecting cylinder 42 into the second lens barrel 2. At this time, the first connecting cylinder 41 and the second connecting cylinder 42 are snapped together and can rotate relative to each other around the axis of the third lens barrel 3, so that the second lens barrel 2 and the third lens barrel 3 can rotate relative to each other.

[0068] Finally, the first fastener 43 is screwed into the through hole 410 until it abuts against the groove wall of the relief groove 201, so that the second lens barrel 2, the first adapter assembly 4, and the third lens barrel 3 are fixed in pairs.

[0069] Another assembly process is as follows:

[0070] First, snap the first connecting cylinder 41 and the second connecting cylinder 42 together and screw them into the second lens barrel 2. Then, screw the first connecting cylinder 41 into the third lens barrel 3. At this time, the first connecting cylinder 41 and the second connecting cylinder 42 are snapped together and can rotate relative to each other around the axis of the third lens barrel 3, so that the second lens barrel 2 and the third lens barrel 3 can rotate relative to each other.

[0071] Finally, the first fastener 43 is screwed into the through hole 410 until it abuts against the groove wall of the relief groove 201, so that the second lens barrel 2, the first adapter assembly 4, and the third lens barrel 3 are fixed in pairs.

[0072] The assembly process of the first lens barrel 1, the second lens barrel 2, and the second adapter assembly 5 is the same as the assembly process of the first adapter assembly, the second lens barrel 2, and the third lens barrel 3, and also includes the two assembly methods mentioned above.

[0073] It should be noted that, in addition to including the second clearance section 22, the main body section 23 and the first clearance section 21 arranged along the object side to the image side, in some other embodiments, the second lens tube 2 may only include the main body section 23 and the first clearance section 21. That is, the second lens tube 2 has the first clearance section 21 only at one end near the image side, and the other end is integrally connected to the first lens tube 1. This is not specifically limited here.

[0074] like Figure 2 and Figure 3 As shown, the optical axis of the coaxial light source 6 ( Figure 3 The vertical direction of the light source 6 is perpendicular to the axis of the second lens tube 2. The interior of the second lens tube 2 is equipped with a 45° beam splitter L7. The light emitted by the coaxial light source 6 enters the interior of the second lens tube 2 through the 45° beam splitter L7.

[0075] The aforementioned 45° beam splitter L7 splits the light emitted from the coaxial light source 6 into two beams through reflection and refraction, with the reflected light and transmitted light typically forming a 90° angle.

[0076] The above configuration makes the optical axis of the coaxial light source 6 parallel to the axis of the first channel 101, improving space utilization and reducing the space required for the telecentric lens.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A telecentric lens barrel, characterized in that, include: The first lens tube (1), the second lens tube (2), and the third lens tube (3) are arranged from the object side to the image side; The first lens tube (1) includes a first channel (101) and a second channel (102) arranged along the object side to the image side. The axis of the second channel (102) is perpendicular to the axis of the first channel (101) and they are connected at the intersection to form an L-shaped connection structure. The second lens barrel (2) is connected to a first adapter assembly (4) and a coaxial light source (6). The coaxial light source (6) is used to provide light to the interior of the second lens barrel (2). One end of the second lens barrel (2) is connected to the second channel (102) of the first lens barrel (1). The other end of the second lens barrel (2) is rotatably connected to the third lens barrel (3) through the first adapter assembly (4). The axis of the first channel (101) is perpendicular to the axis of the second lens barrel (2). The axes of the second channel (102), the second lens barrel (2), and the third lens barrel (3) are parallel to each other.

2. The lens barrel according to claim 1, characterized in that, The end of the second lens barrel (2) away from the first adapter assembly (4) is connected to a second adapter assembly (5), and the first lens barrel (1) and the second lens barrel (2) are rotatably connected through the second adapter assembly (5).

3. The lens barrel according to claim 1, characterized in that, The first adapter assembly (4) includes a first connecting cylinder (41), a second connecting cylinder (42), and a first fastener (43). The first connecting cylinder (41) is screwed to the third lens barrel (3), the second connecting cylinder (42) is screwed to the second lens barrel (2), the first connecting cylinder (41) and the second connecting cylinder (42) are engaged, and the first fastener (43) is used to prevent the second lens barrel (2) and the third lens barrel (3) from rotating relative to each other.

4. The lens barrel according to claim 3, characterized in that, The first connecting tube (41) includes a first tube section (411), a second tube section (412), and a third tube section (413) arranged along the object side to the image side. The third tube section (413) is connected to the third lens tube (3). The inner diameter of the first tube section (411) is smaller than the inner diameter of the second tube section (412), and the inner diameter of the third tube section (413) is smaller than the inner diameter of the second tube section (412). The second connecting tube (42) includes a first tube (421) and a second tube (422) arranged along the object side to the image side. The first tube (421) is connected to the second lens tube (2). The outer diameter of the second tube (422) is larger than the outer diameter of the first tube (421). The outer diameter of the second tube (422) is larger than the inner diameter of the second tube segment (412). The outer diameter of the first tube (421) is smaller than the inner diameter of the second tube segment (412).

5. The lens barrel according to claim 4, characterized in that, The second lens tube (2) has a first clearance section (21) at the end near the image side. The outer diameter of the first clearance section (21) is smaller than the inner diameter of the first tube section (411). The first clearance section (21) is provided with a clearance groove (201), which extends circumferentially along the first connecting tube (41). The first cylindrical section (411) is provided with a through hole (410), which penetrates the first cylindrical section (411) radially along the first connecting cylinder (41). The first fastener (43) is screwed to the through hole (410) and can pass through the through hole (410) to abut against the groove wall of the relief groove (201).

6. The lens barrel according to claim 5, characterized in that, In the axial direction of the second lens tube (2), the length of the first clearance section (21) is less than or equal to the length of the first tube section (411).

7. The lens barrel according to claim 5, characterized in that, The sidewall of the clearance groove (201) near the third lens barrel (3) is inclined relative to the axis of the second lens barrel (2).

8. The lens barrel according to any one of claims 5 to 7, characterized in that, The second adapter assembly (5) includes a third connecting cylinder (51), a fourth connecting cylinder (52), and a second fastener (53). The third connecting cylinder (51) is screwed to the first lens barrel (1), and the fourth connecting cylinder (52) is screwed to the second lens barrel (2). The third connecting cylinder (51) and the fourth connecting cylinder (52) are engaged. The second fastener (53) is used to prevent the first lens barrel (1) and the second lens barrel (2) from rotating relative to each other.

9. The lens barrel according to claim 8, characterized in that, The second lens barrel (2) includes a second clearance section (22), a main body section (23), and a first clearance section (21) arranged along the object side to the image side. The second clearance section (22) is connected to the first lens barrel (1) through the second adapter assembly (5). A light source mounting hole (230) is provided on the side wall of the main body section (23). The coaxial light source (6) is connected to the light source mounting hole (230). The light source mounting hole (230) penetrates one side wall of the main body section (23) along the radial direction of the second lens barrel (2). The structure of the second clearance section (22) and the structure of the first clearance section (21) are axially symmetrical about the axis of the light source mounting hole (230).

10. The lens barrel according to any one of claims 1 to 7, characterized in that, The optical axis of the coaxial light source (6) is perpendicular to the axis of the second lens tube (2). The interior of the second lens tube (2) is provided with a 45° beam splitter prism. The light emitted by the coaxial light source (6) enters the interior of the second lens tube (2) through the 45° beam splitter prism.

11. A telecentric lens, characterized in that, include: The lens tube as described in any one of claims 1 to 10; The first lens group is disposed inside the first lens barrel of the lens barrel; The second lens group is disposed inside the third lens tube of the lens tube.

12. A camera module, characterized in that, include: The telecentric lens as described in claim 11; A photosensitive element (7) is disposed on the image side of the telecentric lens.

Images