Lens eccentricity detection device and assembly method

Abstract

This invention discloses a lens eccentricity detection device and assembly method, belonging to the field of lens eccentricity detection devices and assembly methods. It includes a fixed frame, a lifting assembly, an image measuring head, an internal focusing light source, a horizontal displacement adjustment assembly, a negative pressure adsorption assembly, and a rotary drive mechanism. The lifting assembly and the internal focusing light source are mounted on the fixed frame. The lifting assembly drives the image measuring head to rise and fall. The internal focusing light source is located below the image measuring head. The horizontal displacement adjustment assembly is mounted above the internal focusing light source. The negative pressure adsorption assembly is mounted above the horizontal displacement adjustment assembly. The horizontal displacement adjustment assembly is used to move the negative pressure adsorption assembly on a horizontal plane. The negative pressure adsorption assembly is used to adsorb the lens. The rotary drive mechanism is used to drive the lens to rotate around its optical axis. This embodiment achieves high precision and high stability in lens eccentricity detection due to its low cost, convenient debugging, and simple system composition.

Description

Technical Field

[0001] This invention relates to the technical field of lens eccentricity detection devices and assembly methods, and particularly to a lens eccentricity detection device and assembly method. Background Technology

[0002] During optical lens assembly, it is necessary to detect and minimize the center deviation of the optical system. The center deviation of the optical system in a lens refers to the superposition of the deviations of each lens from the optical axis of the system, or the degree of deviation between the ideal optical axis and the actual optical axis of the optical system. Since optical center deviation disrupts the coaxiality of the optical system, it becomes an important factor affecting image quality. Patent application No. 201810811031.3 discloses an optical lens assembly and testing system, including assembly equipment and image quality testing equipment. The assembly equipment includes an eccentricity measurement device and a mirror spacing measurement device, and the image quality testing equipment includes a wavefront aberration detection device. The eccentricity measurement device includes an optical measuring head, an air-bearing turntable, and a column guide rail. The optical measuring head includes an illumination module, a projection module, a microscopic secondary magnification module, and a first detector. The optical measuring head is slidably connected to the column guide rail and can move up and down along the column guide rail. The air-bearing turntable is used to fix the lens under test. It can detect the eccentricity, spacing, and thickness of the lens under test, as well as the wavefront aberration of the entire lens under test, and evaluate the image quality of the entire lens. This optical lens assembly and testing system requires the use of an air-bearing turntable, which is expensive. Furthermore, before lens testing, dial gauges need to be used to adjust the coaxiality of the lens's mechanical axis, which is a cumbersome adjustment process. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a lens eccentricity detection device and assembly method.

[0004] A lens eccentricity detection device according to an embodiment of the present invention includes: Fixture; A lifting assembly is mounted on the fixed frame; An image measuring head is mounted on the lifting assembly, which is used to move the image measuring head up and down. An internal focusing light source is mounted on the mounting bracket, and the internal focusing light source is located below the image measurement head; A horizontal displacement adjustment assembly is installed above the internal focusing light source; A negative pressure adsorption component is installed above the horizontal displacement adjustment component. The horizontal displacement adjustment component is used to drive the negative pressure adsorption component to move on a horizontal plane. The negative pressure adsorption component is used to adsorb the lens. A rotary drive mechanism is mounted on the fixed frame, and the rotary drive mechanism is used to drive the lens to rotate around the optical axis of the lens.

[0005] The lens eccentricity detection device according to embodiments of the present invention has at least the following beneficial effects: The negative pressure adsorption assembly adsorbs the lens, and the beam emitted by the internal focusing light source is focused after passing through the lens (at the crosshair image focal point). A lifting assembly moves the image measuring head up and down to a suitable position, allowing it to capture a clear crosshair image. The horizontal displacement adjustment assembly then adjusts the crosshair image to the center of the screen. A rotary drive mechanism rotates the lens, and the image measuring head detects the positional changes of the crosshair image during lens rotation. The use of an internal focusing light source reduces the procurement costs of long-stroke linear guides and multi-focal-length front lenses, eliminating the need for dial indicator adjustments on the lens's outer diameter. The negative pressure adsorption assembly and rotary drive mechanism enable lens installation and rotation, reducing the procurement costs of air-bearing turntables and high-precision dial indicators. The negative pressure adsorption device and displacement adjustment assembly ensure rotational accuracy during lens rotation, greatly controlling the impact of radial and axial runout caused by lens rotation on the actual measured value of eccentricity. This system achieves high precision and high stability in lens eccentricity detection with low cost, easy debugging, and simple system composition.

[0006] According to some embodiments of the present invention, the negative pressure adsorption assembly includes a first negative pressure seat and a light-transmitting sheet. The first negative pressure seat is provided with a first light-transmitting hole. The light-transmitting sheet is sealed to the lower end of the first light-transmitting hole. The first negative pressure seat is provided with a first negative pressure hole that communicates with the first light-transmitting hole and is used for connecting an external air extraction device. The upper end of the first negative pressure seat is provided with a first annular protrusion for abutting against a lens.

[0007] According to some embodiments of the present invention, the first negative pressure seat includes a first seat body and a first cover body that are detachably connected. The first negative pressure hole is provided on the first seat body, the first annular protrusion is provided on the first cover body, the light-transmitting sheet is sealed to the lower end of the first seat body, the lower end of the first cover body is provided with a connecting protrusion, the upper end of the first seat body is provided with a connecting groove for the connecting protrusion to extend into, the first light-transmitting hole penetrates the bottom wall of the connecting protrusion and the connecting groove, and a sealing ring is connected between the first seat body and the first cover body.

[0008] According to some embodiments of the present invention, the negative pressure adsorption assembly includes a second negative pressure seat and a sealing plate. The second negative pressure seat is provided with a second light-transmitting hole, and the sealing plate is provided with a third light-transmitting hole. A negative pressure chamber is provided inside the second negative pressure seat. A plurality of adsorption holes are arranged in a circular array on the second negative pressure seat, and the plurality of adsorption holes communicate with the negative pressure chamber. The plurality of adsorption holes are arranged around the second light-transmitting hole. A second negative pressure hole is provided on the second negative pressure seat, which communicates with the negative pressure chamber and is used for connecting an external air extraction device. The sealing plate is rotatably connected to the second negative pressure seat and covers the plurality of adsorption holes. The sealing plate is used to connect a lens to serve as an extension of the lens. The second negative pressure seat is used to adsorb the sealing plate to adsorb the lens.

[0009] According to some embodiments of the present invention, the second negative pressure seat is provided with a second annular protrusion, the second annular protrusion is arranged around the second light-transmitting hole, and a plurality of the adsorption holes penetrate the second annular protrusion.

[0010] According to some embodiments of the present invention, the second negative pressure seat includes a second seat body and a second cover body. The second seat body is provided with an annular adsorption groove and a second negative pressure hole. The second cover body seals the open end of the annular adsorption groove. The space enclosed by the second cover body and the annular adsorption groove forms the negative pressure chamber. The second annular protrusion is provided on the second cover body. The plurality of adsorption holes communicate with the annular adsorption groove.

[0011] According to some embodiments of the present invention, the rotary drive mechanism includes a positioning block, a roller, and a rotary drive assembly. The positioning block is mounted on the fixed frame and has a positioning groove for the lens to extend into. The roller is rotatably connected to the fixed frame and is used to abut against the side of the lens away from the positioning block. The rotary drive assembly is drively connected to the roller and is used to drive the roller to rotate so as to drive the lens to rotate.

[0012] According to some embodiments of the present invention, the rotary drive mechanism further includes a coaxial cylinder for connecting a lens as an extension of the lens, the axial direction of the coaxial cylinder corresponding to the optical axis of the lens, the coaxial cylinder extending into the positioning groove, the roller abutting the side of the coaxial cylinder away from the positioning block, and the rotary drive assembly driving the coaxial cylinder to rotate via the roller, thereby driving the lens to rotate.

[0013] According to some embodiments of the present invention, the rotary drive mechanism further includes two three-dimensional adjustment frames, which are mounted on the fixed frame. The positioning block is mounted above one of the three-dimensional adjustment frames, and the roller and the rotary drive assembly are mounted above the other three-dimensional adjustment frame.

[0014] A lens assembly method according to an embodiment of the present invention, applied in a lens eccentricity detection device, includes the following steps: S1: Mount the lens to be tested onto the negative pressure adsorption assembly; S2: The lifting assembly drives the image measurement head to rise and fall, and works with the internal focusing light source to achieve automatic focusing; S3: The rotary drive mechanism drives the lens under test to rotate and records the focal image of the lens under test at various angles; S4: Perform centroid identification and analysis on the focal image of the lens under test at different angles, and then perform fitting and circle drawing; S5: Calculate eccentricity detection based on the radius of the circle and the position of the image measuring head; S6: Determine whether the eccentricity test result is qualified. If the eccentricity test result is not qualified, adjust the position of the lens in the lens to center it before proceeding to step S3. If the eccentricity test result is qualified, the eccentricity test is completed and the centering is completed. Apply glue to the lens under test for assembly.

[0015] The lens assembly method according to embodiments of the present invention has at least the following beneficial effects: The negative pressure adsorption assembly adsorbs the lens, and the beam emitted by the internal focusing light source is focused after passing through the lens (at the crosshair image focal point). A lifting assembly moves the image measuring head up and down to a suitable position, allowing it to capture a clear crosshair image. The horizontal displacement adjustment assembly then adjusts the crosshair image to the center of the screen. A rotary drive mechanism rotates the lens, and the image measuring head detects the positional changes of the crosshair image during lens rotation. The use of an internal focusing light source reduces the procurement costs of long-stroke linear guides and multi-focal-length front lenses, eliminating the need for dial indicator adjustments on the lens's outer diameter. The negative pressure adsorption assembly and rotary drive mechanism enable lens installation and rotation, reducing the procurement costs of air-bearing turntables and high-precision dial indicators. The negative pressure adsorption device and displacement adjustment assembly ensure rotational accuracy during lens rotation, greatly controlling the impact of radial and axial runout caused by lens rotation on the actual measured value of eccentricity. This system achieves high precision and high stability in lens eccentricity detection with low cost, easy debugging, and simple system composition.

[0016] Additional aspects and advantages of the invention will be set forth in part in the description which follows. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a schematic diagram of the structure of the first lens eccentricity detection device according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the lens and negative pressure adsorption assembly of the first lens eccentricity detection device according to an embodiment of the present invention; Figure 3This is a cross-sectional view of the lens and negative pressure adsorption assembly of the first lens eccentricity detection device according to an embodiment of the present invention. Figure 4 This is a schematic diagram of the structure of the first base of the first lens eccentricity detection device according to an embodiment of the present invention; Figure 5 This is an exploded structural diagram of the lens and negative pressure adsorption assembly of the second type of lens eccentricity detection device according to an embodiment of the present invention. Figure 6 This is a cross-sectional view of the lens and negative pressure adsorption assembly of the second lens eccentricity detection device according to an embodiment of the present invention. Figure 7 This is an exploded structural diagram of the lens and negative pressure adsorption assembly of the third lens eccentricity detection device according to an embodiment of the present invention. Figure 8 This is a cross-sectional view of the lens and negative pressure adsorption assembly of the third lens eccentricity detection device according to an embodiment of the present invention. Figure 9 This is a schematic diagram of the positioning block of the lens eccentricity detection device according to an embodiment of the present invention.

[0018] Icon labels: 100. Fixture; 110. Lifting assembly; 120. Image measuring head; 130. Internal focusing light source; 140. Horizontal displacement adjustment assembly; 200. Negative pressure adsorption assembly; 210. First negative pressure seat; 211. First light-transmitting hole; 212. First seat body; 2121. First negative pressure hole; 2122. Connecting groove; 213. First cover body; 2131. First annular protrusion; 2132. Connecting protrusion; 214. Sealing ring; 220. Light-transmitting sheet; 230. Second negative pressure seat; 231. Second light-transmitting hole; 232. Negative pressure chamber; 233. Second seat body; 2331. Second negative pressure hole; 234. Second cover body; 2341. Second annular protrusion; 2342. Adsorption hole; 240. Sealing plate; 241. Third light-transmitting hole; 300. Rotary drive mechanism; 310. Positioning block; 311. Positioning groove; 320. Roller; 330. Rotary drive assembly; 340. Coaxial cylinder; 350. Three-dimensional adjustment frame; 400. Lens. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Please see Figure 1 , Figure 2 and Figure 3 According to an embodiment of the present invention, a lens 400 eccentricity detection device includes a fixed frame 100, a lifting assembly 110, an image measuring head 120, an internal focusing light source 130, a horizontal displacement adjustment assembly 140, a negative pressure adsorption assembly 200, and a rotation drive mechanism. The lifting assembly 110 is mounted on the fixed frame 100, and the image measuring head 120 is mounted on the lifting assembly 110. The lifting assembly 110 is used to drive the image measuring head 120 to move up and down. The lifting assembly 110 includes a lifting motor, a lifting lead screw, a lifting guide rod, and a lifting nut. The lifting motor drives the lifting lead screw to rotate, the lifting nut is threadedly connected to the lifting lead screw, and the lifting nut is slidably connected to the lifting guide rod. The lifting guide rod restricts the rotation of the lifting nut, and the image measuring head 120 is mounted on the lifting nut. The image measuring head 120 internally houses a CCD or CMOS sensor for capturing the cross-shaped image focus.

[0023] The internal focusing light source 130 is existing technology and is mounted on the mounting bracket 100, located below the image measuring head 120. The internal focusing light source 130 includes a light source system, a spherical mirror, a focusing objective lens group, a reticle, a plane mirror, and an image-rotating objective lens. The light source system uses high-efficiency LEDs to uniformly illuminate the spherical mirror through a condenser lens and a reflecting prism. The spherical mirror is coated with an aluminum total reflection film and has a cross-shaped cutout as an imaging reference surface. The focusing objective lens group consists of a movable lens group and a fixed lens group; the focal length of the objective lens is changed by axially moving the movable lens group. The reticle is used to observe the degree of overlap between the crosshair image and the reflected image to determine the focusing accuracy. The plane mirror and the image-rotating objective lens flex the image plane onto the reticle.

[0024] A horizontal displacement adjustment assembly 140 is mounted above the internal focusing light source 130, and a negative pressure adsorption assembly 200 is mounted above the horizontal displacement adjustment assembly 140. The horizontal displacement adjustment assembly 140 is used to drive the negative pressure adsorption assembly 200 to move on a horizontal plane, and the negative pressure adsorption assembly 200 is used to adsorb the lens 400. A rotary drive mechanism 300 is mounted on the fixed frame 100, and the rotary drive mechanism 300 is used to drive the lens 400 to rotate around the optical axis of the lens 400. The horizontal displacement adjustment assembly 140 includes a horizontal adjustment seat and a slide. The negative pressure adsorption assembly 200 is mounted on the slide. A through hole is provided in the middle of the slide, and the slide is slidably connected to the horizontal adjustment seat. The horizontal adjustment seat is provided with two adjusting threaded holes. The axes of the two adjusting threaded holes are perpendicular to each other (or normally intersecting) and located on a horizontal plane. An adjusting bolt passes through the adjusting threaded hole and abuts against the slide. The slide moves on a horizontal plane by rotating the adjusting bolt.

[0025] The negative pressure adsorption component 200 adsorbs the lens 400. The beam emitted by the internal focusing light source 130 is focused after passing through the lens 400 (at the crosshair focal point). The lifting component 110 moves the image measuring head 120 up and down to a suitable position, allowing the image measuring head 120 to capture a clear crosshair image. The horizontal displacement adjustment component 140 adjusts the crosshair image to the center of the screen. The rotation drive mechanism 300 drives the lens 400 to rotate, and the image measuring head 120 detects the positional change of the crosshair image during the rotation of the lens 400. Using the internal focusing light source 130 reduces the procurement costs of long-stroke linear guides and multi-focal-length front lenses, and eliminates the need for dial indicator adjustments on the outer diameter of the lens 400. The negative pressure adsorption component 200 and the rotation drive mechanism 300 enable the installation and rotation of the lens 400, reducing the procurement costs of air-bearing turntables and high-precision dial indicators. The negative pressure adsorption device and displacement adjustment component ensure the rotational accuracy of the lens 400, greatly controlling the impact of radial and axial runout caused by the rotation of the lens 400 on the actual measured value of the eccentricity. With its low cost, convenient debugging and simple system composition, it achieves the high precision and high stability requirements of lens 400 eccentricity detection.

[0026] During the debugging process, good machining accuracy can be used to ensure the parallelism between the reference platform and the reference surface of the lens 400 or the perpendicularity between the reference platform and the rotation axis of the lens 400. Since the rotation method of this embodiment is that the lens 400 rotates with its own mechanical axis as the reference axis, the coaxiality (the coaxiality between the optical axis of the image measuring head 120 and the mechanical axis of the lens 400 under test) will not affect the true value of the eccentricity detection. Under good machining accuracy, the tilt between the mechanical axis of the lens 400 and the optical axis of the image measuring head 120 has a very small impact on the eccentricity value during eccentricity detection.

[0027] In some embodiments, see Figure 1 , Figure 2 and Figure 3 In the first type of lens 400 eccentricity detection device, the reference axis of the lens 400 under test is its own mechanical axis and it has good airtightness. The negative pressure adsorption assembly 200 includes a first negative pressure seat 210 and a light-transmitting plate 220. The first negative pressure seat 210 is provided with a first light-transmitting hole 211. The light-transmitting plate 220 is sealed and covered at the lower end of the first light-transmitting hole 211. The light-transmitting plate 220 has high transmittance to the light source while ensuring airtightness. The first negative pressure seat 210 is provided with a first negative pressure hole 2121. The first negative pressure hole 2121 is connected to the first light-transmitting hole 211. The first negative pressure hole 2121 is connected to an external air extraction device through a connector. The air extraction device extracts air, so that a negative pressure is generated at the upper end of the first light-transmitting hole 211 to adsorb the lens 400. The upper end of the first negative pressure seat 210 is provided with a first annular protrusion 2131. The first annular protrusion 2131 is used to abut against the lower end of the lens 400. The surface of the first annular protrusion 2131 has good flatness, which can ensure that the end face of the lens 400 is not scratched, reduce the contact area between the lens 400 and the first negative pressure seat 210, reduce the friction between the lens 400 and the first negative pressure seat 210, and ensure the smoothness and stability of the rotation of the lens 400.

[0028] In some embodiments, see Figure 1 , Figure 2 and Figure 3 The first negative pressure seat 210 includes a detachably connected first seat body 212 and a first cover body 213. A first negative pressure hole 2121 is provided on the first seat body 212, and a first annular protrusion 2131 is provided on the first cover body 213. A light-transmitting sheet 220 is sealed to the lower end of the first seat body 212. The detachable first seat body 212 and first cover body 213 allow the first cover body 213 to be replaced with different sizes to accommodate different lenses 400. A connecting protrusion 2132 is provided at the lower end of the first cover body 213. (See reference...) Figure 4The first base 212 has a connecting groove 2122 at its upper end, into which the connecting protrusion 2132 extends. The first light-transmitting hole 211 penetrates the bottom wall of the connecting protrusion 2132 and the connecting groove 2122. A sealing ring 214 connects the first base 212 and the first cover 213. The first cover 213 and the first base 212 are connected by the connecting protrusion 2132 and the connecting groove 2122, and the connection is stable.

[0029] In some embodiments, see Figure 1 , Figure 5 and Figure 6 In the second type of lens 400 eccentricity detection device, the reference axis of the lens 400 under test is its own mechanical axis, but its airtightness is poor. The negative pressure adsorption assembly 200 includes a second negative pressure seat 230 and a sealing disk 240. The second negative pressure seat 230 is provided with a second light-transmitting hole 231, and the sealing disk 240 is provided with a third light-transmitting hole 241. A negative pressure chamber 232 is provided inside the second negative pressure seat 230. Multiple adsorption holes 2342 are arranged in a circular array on the second negative pressure seat 230, connecting to the negative pressure chamber 232 and surrounding the second light-transmitting hole 231. A second negative pressure hole 2331 is provided on the second negative pressure seat 230, connecting to the negative pressure chamber 232. The second negative pressure hole 2331 is connected to an external air extraction device via a connector. A sealing disc 240 is rotatably connected to a second negative pressure seat 230. The sealing disc 240 covers multiple suction holes 2342. The sealing disc 240 is connected to the lens 400 to serve as an extension of the lens 400. The second negative pressure seat 230 is used to adsorb the sealing disc 240 to adsorb the lens 400. When the suction device draws air, a negative pressure is generated in the negative pressure chamber 232. This negative pressure is transmitted to the sealing disc 240 through the suction holes 2342. The second negative pressure seat 230 adsorbs the sealing disc 240, and subsequently, the lens 400.

[0030] In some embodiments, see Figure 1 , Figure 5 and Figure 6 The second negative pressure seat 230 is provided with a second annular protrusion 2341, which surrounds the second light-transmitting hole 231. Multiple adsorption holes 2342 pass through the second annular protrusion 2341. The surface of the second annular protrusion 2341 has good flatness, which can reduce the contact area between the lens 400 and the second negative pressure seat 230, reduce the friction between the lens 400 and the second negative pressure seat 230, and ensure the smoothness and stability of the lens 400 during rotation.

[0031] In some embodiments, see Figure 1 , Figure 5 and Figure 6The second negative pressure seat 230 includes a second seat body 233 and a second cover body 234. The second seat body 233 is provided with an annular adsorption groove and a second negative pressure hole 2331. The second cover body 234 seals the open end of the annular adsorption groove. The space enclosed by the second cover body 234 and the annular adsorption groove forms a negative pressure chamber 232. A second annular protrusion 2341 is provided on the second cover body 234, and multiple adsorption holes 2342 communicate with the annular adsorption groove. The second seat body 233 and the second cover body 234 are separately arranged, which facilitates the processing of the annular adsorption groove on the second seat body 233 and the processing of multiple adsorption holes 2342 on the second cover body 234. The processing is convenient, and it is also convenient to replace the second cover body 234 of different specifications to adapt to different specifications of lenses 400.

[0032] In some embodiments, see Figure 1 , Figure 2 and Figure 9 The rotary drive mechanism 300 includes a positioning block 310, a roller 320, and a rotary drive assembly 330. The positioning block 310 is mounted on the fixed frame 100 and has a positioning groove 311, which is a V-shaped groove, for the lens 400 to extend into. The roller 320 is rotatably connected to the fixed frame 100 and abuts against the side of the lens 400 away from the positioning block 310. The rotary drive assembly 330 is drively connected to the roller 320 and drives the roller 320 to rotate, thereby rotating the lens 400. The positioning groove 311, being a V-shaped groove, works with the roller 320 to achieve three-point positioning of the lens 400, limiting the radial runout of the lens 400. The rotary drive assembly 330 includes a rotary drive motor, which drives the roller 320 to rotate via a pulley, thereby rotating the lens 400 through friction.

[0033] In some embodiments, see Figure 1 , Figure 7 and Figure 8 In the third type of lens 400 eccentricity detection device, for some special lenses 400, that is, lenses whose barrel shape is not circular, a position with coaxiality or perpendicularity requirements with the optical axis of the optical system is needed as the reference for fixture design. The rotary drive mechanism 300 also includes a coaxial cylinder 340, which is used to connect the lens 400 as an extension of the lens 400. The axis of the coaxial cylinder 340 corresponds to the optical axis of the lens 400. The coaxial cylinder 340 extends into the positioning groove 311, and the roller 320 abuts against the side of the coaxial cylinder 340 away from the positioning block 310. The rotary drive assembly 330 drives the coaxial cylinder 340 to rotate through the roller 320, thereby driving the lens 400 to rotate. By setting the coaxial cylinder 340 as an extension of the reference axis of the irregular lens 400, the lens 400 eccentricity detection device is not limited by the shape of the lens 400. Automatic eccentricity detection and assembly can be achieved for both conventional cylindrical lenses 400 and unconventional square barrel lenses 400.

[0034] In some embodiments, see Figure 1 The rotary drive mechanism 300 also includes two three-dimensional adjustment frames 350. The fixed frame 100 includes a lifting frame and a base plate. The lifting frame is mounted on the base plate, the lifting assembly 110 is mounted on the lifting frame, and the internal focusing light source is mounted on the base plate. The two three-dimensional adjustment frames 350 are mounted on the base plate. A positioning block 310 is mounted above one three-dimensional adjustment frame 350, and a roller 320 and a rotary drive assembly 330 are mounted above the other three-dimensional adjustment frame 350. The three-dimensional adjustment frames 350 can be translated in the X, Y, and Z directions with high adjustment accuracy. The three-dimensional adjustment frames 350 are configured so that the positioning block 310, roller 320, and rotary drive assembly 330 can meet the inspection requirements of the lens 400.

[0035] A lens 400 assembly method according to an embodiment of the present invention, applied in a lens 400 eccentricity detection device, includes the following steps: S1: The lens 400 under test is mounted on the negative pressure adsorption assembly 200. The air extraction device extracts air, and a negative pressure is generated at the connection between the negative pressure adsorption assembly 200 and the lens 400 under test, causing the lens 400 under test to be adsorbed.

[0036] S2: The lifting assembly 110 drives the image measuring head 120 to rise and fall, coordinating with the internal focusing light source 130 for autofocus. First, move the measuring head to an approximate position (e.g., 40mm) at a distance of 400mm from the top of the lens. Then, adjust the internal focusing device so that the CCD or CMOS sensor can capture the crosshair image focus. Next, fine-tune the position of the image measuring head 120 to present the clearest crosshair image on the sensor, and adjust the crosshair image to the center of the screen using the horizontal displacement adjustment device.

[0037] S3: The rotary drive mechanism 300 drives the lens under test 400 to rotate, recording the focal image of the lens under test 400 at various angles. The rotary drive mechanism 300 is controlled to rotate the lens 400, and sensors are used to accurately record the positional changes of the crosshair image during the rotation of the lens 400.

[0038] S4: Perform centroid identification and analysis on the focal image of the lens under test at 400° different angles, and then perform circle fitting analysis. Utilize software algorithms to perform circle fitting analysis on multiple sets of collected data, automatically determining the direction and magnitude of the eccentricity.

[0039] S5: Calculate eccentricity detection based on the radius of the circle and the position of the image measuring head 120.

[0040] S6: Determine if the eccentricity test result is acceptable. If the eccentricity test result is unacceptable, adjust the position of the lens element in lens 400 for centering before proceeding to step S3. If the eccentricity test result is acceptable, the eccentricity test and centering are complete. Apply adhesive to the tested lens 400 for assembly. Based on the test results, determine if the calculated eccentricity value is acceptable. If it is unacceptable, adjust the lens element of lens 400 according to the eccentricity direction until the eccentricity value is acceptable.

[0041] The negative pressure adsorption component 200 adsorbs the lens 400. The beam emitted by the internal focusing light source 130 is focused after passing through the lens 400 (at the crosshair focal point). The lifting component 110 moves the image measuring head 120 up and down to a suitable position, allowing the image measuring head 120 to capture a clear crosshair image. The horizontal displacement adjustment component 140 adjusts the crosshair image to the center of the screen. The rotation drive mechanism 300 drives the lens 400 to rotate, and the image measuring head 120 detects the positional change of the crosshair image during the rotation of the lens 400. Using the internal focusing light source 130 reduces the procurement costs of long-stroke linear guides and multi-focal-length front lenses, and eliminates the need for dial indicator adjustments on the outer diameter of the lens 400. The negative pressure adsorption component 200 and the rotation drive mechanism 300 enable the installation and rotation of the lens 400, reducing the procurement costs of air-bearing turntables and high-precision dial indicators. The negative pressure adsorption device and displacement adjustment component ensure the rotational accuracy of the lens 400, greatly controlling the impact of radial and axial runout caused by the rotation of the lens 400 on the actual measured value of the eccentricity. With its low cost, convenient debugging and simple system composition, it achieves the high precision and high stability requirements of lens 400 eccentricity detection.

[0042] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0043] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A lens eccentricity detection device, characterized in that, include: Fixture; A lifting assembly is mounted on the fixed frame; An image measuring head is mounted on the lifting assembly, which is used to move the image measuring head up and down. An internal focusing light source is mounted on the mounting bracket, and the internal focusing light source is located below the image measurement head; A horizontal displacement adjustment assembly is installed above the internal focusing light source; A negative pressure adsorption component is installed above the horizontal displacement adjustment component. The horizontal displacement adjustment component is used to drive the negative pressure adsorption component to move on a horizontal plane. The negative pressure adsorption component is used to adsorb the lens. A rotary drive mechanism is mounted on the fixed frame, and the rotary drive mechanism is used to drive the lens to rotate around the optical axis of the lens.

2. The lens eccentricity detection device according to claim 1, characterized in that, The negative pressure adsorption assembly includes a first negative pressure seat and a light-transmitting sheet. The first negative pressure seat is provided with a first light-transmitting hole. The light-transmitting sheet is sealed and covered at the lower end of the first light-transmitting hole. The first negative pressure seat is provided with a first negative pressure hole that communicates with the first light-transmitting hole and is used for connecting an external air extraction device. The upper end of the first negative pressure seat is provided with a first annular protrusion for abutting against a lens.

3. The lens eccentricity detection device according to claim 2, characterized in that, The first negative pressure seat includes a first seat body and a first cover body that are detachably connected. The first negative pressure hole is provided on the first seat body, the first annular protrusion is provided on the first cover body, the light-transmitting sheet is sealed to the lower end of the first seat body, the lower end of the first cover body is provided with a connecting protrusion, the upper end of the first seat body is provided with a connecting groove for the connecting protrusion to extend into, the first light-transmitting hole penetrates the bottom wall of the connecting protrusion and the connecting groove, and a sealing ring is connected between the first seat body and the first cover body.

4. The lens eccentricity detection device according to claim 1, characterized in that, The negative pressure adsorption assembly includes a second negative pressure seat and a sealing plate. The second negative pressure seat has a second light-transmitting hole, and the sealing plate has a third light-transmitting hole. The second negative pressure seat has a negative pressure chamber inside. The second negative pressure seat has a plurality of adsorption holes arranged in a circular array, which are connected to the negative pressure chamber and arranged around the second light-transmitting hole. The second negative pressure seat has a second negative pressure hole that is connected to the negative pressure chamber and is used for connecting an external air extraction device. The sealing plate is rotatably connected to the second negative pressure seat and covers the plurality of adsorption holes. The sealing plate is used to connect a lens to serve as an extension of the lens. The second negative pressure seat is used to adsorb the sealing plate to adsorb the lens.

5. The lens eccentricity detection device according to claim 4, characterized in that, The second negative pressure seat is provided with a second annular protrusion, which surrounds the second light-transmitting hole, and a plurality of adsorption holes penetrate the second annular protrusion.

6. The lens eccentricity detection device according to claim 5, characterized in that, The second negative pressure seat includes a second seat body and a second cover body. The second seat body is provided with an annular adsorption groove and a second negative pressure hole. The second cover body seals the open end of the annular adsorption groove. The space enclosed by the second cover body and the annular adsorption groove forms the negative pressure chamber. The second annular protrusion is provided on the second cover body. The plurality of adsorption holes are connected to the annular adsorption groove.

7. The lens eccentricity detection device according to claim 1, characterized in that, The rotary drive mechanism includes a positioning block, a roller, and a rotary drive assembly. The positioning block is mounted on the fixed frame and has a positioning groove for the lens to extend into. The roller is rotatably connected to the fixed frame and is used to abut against the side of the lens away from the positioning block. The rotary drive assembly is drively connected to the roller and is used to drive the roller to rotate, thereby driving the lens to rotate.

8. The lens eccentricity detection device according to claim 7, characterized in that, The rotary drive mechanism also includes a coaxial cylinder for connecting a lens as an extension of the lens. The axial direction of the coaxial cylinder corresponds to the optical axis of the lens. The coaxial cylinder extends into the positioning groove. The roller abuts against the side of the coaxial cylinder away from the positioning block. The rotary drive assembly drives the coaxial cylinder to rotate through the roller, thereby driving the lens to rotate.

9. The lens eccentricity detection device according to claim 7, characterized in that, The rotary drive mechanism further includes two three-dimensional adjustment frames, which are mounted on the fixed frame. The positioning block is mounted above one of the three-dimensional adjustment frames, and the roller and the rotary drive assembly are mounted above the other three-dimensional adjustment frame.

10. A lens assembly method, applied in the lens eccentricity detection device as described in any one of claims 1-9, characterized in that, Includes the following steps: S1: Mount the lens to be tested onto the negative pressure adsorption assembly; S2: The lifting assembly drives the image measurement head to rise and fall, and works with the internal focusing light source to achieve automatic focusing; S3: The rotary drive mechanism drives the lens under test to rotate and records the focal image of the lens under test at various angles; S4: Perform centroid identification and analysis on the focal image of the lens under test at different angles, and then perform fitting and circle drawing; S5: Calculate eccentricity detection based on the radius of the circle and the position of the image measuring head; S6: Determine whether the eccentricity test result is qualified. If the eccentricity test result is not qualified, adjust the position of the lens in the lens to achieve centering before proceeding to step S3. If the eccentricity test result is qualified, the eccentricity test is completed and the centering is completed. Apply glue to the lens under test for assembly.

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