An ophthalmic lens defect detection vision system and detection apparatus

Abstract

This invention provides a visual system for detecting defects in eyeglass lenses, comprising a first visual inspection module and a second visual inspection module sequentially arranged at different workstations. The first visual inspection module includes a first inspection camera and a first inspection light source, which is a ring light source. The second visual inspection module includes a second inspection camera and a second inspection light source, which is a coaxial light source. Special reflective films are respectively disposed below the first and second inspection light sources, and these films are positioned below the sample during inspection. Through dual-workstation collaborative inspection, optimized optical path of the special reflective films, and high-speed dynamic imaging technology, this system solves the pain points of insufficient sensitivity, low efficiency, and poor compatibility in traditional lens defect detection, providing a high-precision, low-cost automated quality inspection solution for the eyewear manufacturing industry, significantly improving product yield and market competitiveness.

Description

Technical Field

[0001] This utility model relates to the field of optics, and in particular to a visual system and detection equipment for detecting defects in eyeglass lenses. Background Technology

[0002] As a crucial optical component for vision correction, the surface quality of eyeglass lenses directly impacts the wearer's visual experience. Common lens defects include scratches, bubbles, chipping, and spots. These defects may originate from impurities in raw materials, fluctuations in manufacturing processes, or unclean processing environments. Traditional inspection methods primarily rely on manual visual inspection, which presents the following problems:

[0003] Low efficiency: Manual inspection is slow and cannot meet the high-capacity demands of automated production lines. High subjectivity: Inspection results are easily affected by personnel experience and fatigue, leading to high rates of missed and false positives. High cost: Requires a large investment of manpower and strict training requirements for inspection personnel.

[0004] In recent years, machine vision technology has been gradually applied to lens defect detection, but existing solutions still have limitations, such as single detection modes, insufficient sensitivity, inability to cover all types of defects, severe optical path interference, and highly reflective materials easily causing specular reflection, leading to image overexposure or stray light interference. Therefore, an improvement measure is urgently needed. Utility Model Content

[0005] This invention provides a vision system and inspection equipment for detecting defects in eyeglass lenses. Through dual-station collaborative inspection, special reflective film optical path optimization, and high-speed dynamic imaging technology, it solves the pain points of insufficient sensitivity, low efficiency, and poor compatibility in traditional lens defect inspection. It provides a high-precision, low-cost automated quality inspection solution for the eyewear manufacturing industry, significantly improving product yield and market competitiveness.

[0006] The present invention specifically adopts the following technical solution: a visual system for detecting defects in eyeglass lenses, comprising a first visual detection module and a second visual detection module sequentially arranged at different workstations. The first visual detection module includes a first detection camera and a first detection light source, wherein the first detection light source is a ring light source. The second visual detection module includes a second detection camera and a second detection light source, wherein the second detection light source is a coaxial light source. Reflective films are respectively provided below the first detection light source and the second detection light source, and the reflective films are located below the detection sample during detection.

[0007] As a further improved technical solution, the lens of the first detection camera and the first detection light source are positioned above the detection sample, at distances of 205±20mm and 20±10mm from the detection sample below, respectively.

[0008] As a further improved technical solution, the lens of the second detection camera and the second detection light source are positioned above the detection sample, at distances of 205±20mm and 50±10mm from the detection sample below, respectively.

[0009] As a further improved technical solution, the reflective film located below the first detection light source is 10±10mm away from the detection sample.

[0010] As a further improved technical solution, the reflective film located below the second detection light source is 30±10mm away from the detection sample.

[0011] As a further improved technical solution, the reflective film is a coated semi-transparent mirror reflective film.

[0012] A defect detection device for eyeglass lenses includes a machine base, a conveyor line, and two sets of the aforementioned defect detection vision systems.

[0013] As a further improved technical solution, the two sets of defect detection vision systems are respectively installed above and below the conveyor line to complete the detection of both sides of the sample during the conveying process.

[0014] A defect detection device for eyeglass lenses includes a machine base, a conveyor line, the aforementioned defect detection vision system, and a flipping mechanism. The first and second vision detection modules of the defect detection vision system are mounted above the conveyor line. The conveyor line carries the test sample sequentially under the first and second vision detection modules. The flipping mechanism is located at one end of the conveyor line to flip the test sample.

[0015] The visual system and testing equipment for detecting defects in eyeglass lenses of this invention have the effect of improving the comprehensiveness and reliability of defect detection, and can significantly improve the efficiency of eyeglass lens defect detection.

[0016] I. Design of a dual-station multimodal optical collaborative inspection system. Station 1 (ring light source + dark field inspection): Utilizing a low-angle ring light source with a special reflective film to suppress specular reflection, capturing only the scattered light from defects. This is suitable for detecting minute scratches (submicron level), edge chipping, and surface particle contamination. In dark field mode, defects appear as bright spots, with sensitivity more than 3 times higher than traditional bright field inspection. Station 2 (coaxial light source + bright field inspection): Perpendicularly incident light is reflected by the reflective film and uniformly covers the lens surface, directly imaging macroscopic defects (such as bubbles, stones, and large-area scratches). In bright field mode, defects appear as dark spots, allowing for the quantification of defect size and shape, complementing dark field inspection.

[0017] II. A special reflective film optimizes the optical path. The polycrystalline semi-transparent coating design reduces stray light interference, improves image quality, and allows even minute defects to be captured more clearly. Precise distance control allows for dynamic adjustment of the distance between the reflective film and the lens, adapting to lenses of different curvatures (spherical / aspherical) and avoiding optical path distortion.

[0018] Furthermore, the images and data generated during the testing process by the equipment described in this application can be recorded and stored, facilitating subsequent quality analysis and traceability. This helps companies conduct quality control and process optimization, thereby improving the overall quality level of their products. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the visual system of this application.

[0020] Figure 2 This is a schematic diagram of the first vision detection module in this application.

[0021] Figure 3 This is a schematic diagram of the second visual inspection module of this application. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "set up" and "connection" 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; they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood through the specific circumstances. Example 1

[0024] Combination Figures 1-2 This embodiment of a visual system for detecting defects in eyeglass lenses includes a first visual inspection module 1 and a second visual inspection module 2 arranged sequentially at different workstations. The first visual inspection module 1 includes a first inspection camera 11 and a first inspection light source 12, which is a ring light source. The second visual inspection module 2 includes a second inspection camera 21 and a second inspection light source 22, which is a coaxial light source. A reflective film 3 is provided below the first inspection light source 12 and the second inspection light source 22, respectively. The reflective film 3 is located below the inspection sample 4 during inspection.

[0025] The reflective film 3 is a coated semi-transparent mirror reflective film, such as a polycrystalline metal film, which is formed on a substrate by physical vapor deposition (PVD) of metal elements (such as aluminum, silver, etc.); or a polycrystalline metal oxide film, which is made by chemical vapor deposition (CVD) or sol-gel method, with metal oxides (such as titanium dioxide, zinc oxide, etc.) as the main components.

[0026] Specific references Figure 1 The lens 13 of the first detection camera and the first detection light source 12 are positioned above the sample 4 at distances of WD1=205±20mm and LWD1=20±10mm, respectively. Simultaneously, the reflective film 3 located below the first detection light source 12 is at a distance of H1=10±10mm from the sample 4. The configuration of the first visual inspection module 1 forms an optical dark-field detection system. The first light source 12 illuminates the sample surface at a low angle, and the light is mainly reflected or scattered. Smooth areas on the surface of the sample 4 reflect light that does not enter the detection system, while defective areas scatter light, which enters the detection system and forms bright spots. This mainly detects scratches, bumps, and edge chipping on the lens surface.

[0027] Reference Figure 2 The lens 23 of the second inspection camera and the second inspection light source 22 are positioned above the inspection sample 4 at distances of WD2=205±20mm and LWD2=50±10mm, respectively. Simultaneously, the reflective film 3 located below the second inspection light source 22 is at a distance of H2=30±10mm from the inspection sample 4. This configuration of the second visual inspection module 2 forms an optical bright-field inspection system. The second inspection light source 22 emits high-intensity uniform light through a high-density LED array. This light is reflected by the reflective film and ultimately forms an image on the same axis as the second inspection camera 21. This design effectively eliminates ghosting and reflection phenomena in the acquired image. This illumination method ensures that the object receives relatively uniform light, making it effective for detecting defects such as stones, scratches, and spots on the lens surface.

[0028] For scratch detection, both the first vision detection module 1 and the second vision detection module 2 are involved. Since the scratch image acquired by the camera presents different gray levels of defects in dark and bright fields, with white scratches in dark fields and black scratches in bright fields, and the scratches are directional, the dual detection setup of the first vision detection module 1 and the second vision detection module 2 can complement each other to prevent low contrast of directional defects, thereby improving detection accuracy. Example 2

[0029] This embodiment provides a defect detection device for eyeglass lenses, including a machine base, a conveyor line, two sets of defect detection vision systems from Embodiment 1, and a display. The two sets of defect detection vision systems are respectively mounted above and below the conveyor line, completing the detection of both sides of the sample during transport. This automated machine vision inspection equipment is low-cost, offers high efficiency in non-contact measurement, has a high detection rate, and is compatible with complex and diverse products. During online inspection, the camera performs high-speed detection, acquires signal-received images, processes them using algorithms, and directly outputs product inspection results and inspection data. Example 3

[0030] This embodiment provides a spectacle lens defect detection device, including a machine base, a conveyor line, a defect detection vision system as described in Embodiment 1, a flipping mechanism, and a display. The first vision detection module 1 and the second vision detection module 2 of the defect detection vision system are mounted above the conveyor line. The conveyor line carries the test sample sequentially under the first vision detection module 1 and the second vision detection module 2. The flipping mechanism is located at one end of the conveyor line and flips the test sample. After the test sample is flipped, the conveyor line reverses direction, and the sample passes under the first vision detection module 1 and the second vision detection module 2 a second time for detection of the other side. The flipping mechanism can be an existing flipping mechanism, such as a combination of a motor and a cylinder gripper, which clamps and flips the test sample, or other existing mechanisms capable of flipping. The conveyor line can also be an existing conveying mechanism, such as a belt conveyor. The parts that can be achieved using existing technology are not described in detail here, as this does not affect the understanding and implementation of this technical solution.

[0031] Furthermore, the above embodiments are only used to illustrate the present utility model and are not intended to limit the technical solutions described in the present utility model. The understanding of this specification should be based on those skilled in the art. Although the present utility model has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to the present utility model. All technical solutions and improvements that do not depart from the spirit and scope of the present utility model should be covered within the scope of the claims of the present utility model.

Claims

1. A visual system for detecting defects in spectacle lenses, characterized in that: The system includes a first visual inspection module and a second visual inspection module arranged sequentially at different workstations. The first visual inspection module includes a first inspection camera and a first inspection light source, which is a ring light source. The second visual inspection module includes a second inspection camera and a second inspection light source, which is a coaxial light source. Reflective films are respectively provided below the first and second inspection light sources, and the reflective films are located below the inspection sample during inspection.

2. The visual system for detecting defects in spectacle lenses according to claim 1, characterized in that: The lens of the first detection camera and the first detection light source are above the detection sample, at a distance of 205±20mm and 20±10mm from the detection sample below, respectively.

3. The visual system for detecting defects in spectacle lenses according to claim 1, characterized in that: The lens of the second detection camera and the second detection light source are located above the detection sample, at distances of 205±20mm and 50±10mm from the detection sample below, respectively.

4. The visual system for detecting defects in spectacle lenses according to claim 1, characterized in that: The reflective film located below the first detection light source is 10±10mm away from the detection sample.

5. The visual system for detecting defects in spectacle lenses according to claim 1, characterized in that: The reflective film located below the second detection light source is 30±10mm away from the detection sample.

6. The visual system for detecting defects in spectacle lenses according to claim 1, characterized in that: The reflective film is a coated semi-transparent mirror reflective film.

7. A spectacle lens defect detection device, characterized in that: It includes a machine, a conveyor line, and two defect detection vision systems as described in any one of claims 1-6.

8. The spectacle lens defect detection device according to claim 7, characterized in that: The two defect detection vision systems are respectively installed above and below the conveyor line to complete the detection of both sides of the sample during the conveying process.

9. A spectacle lens defect detection device, characterized in that: The device includes a machine, a conveyor line, a defect detection vision system as described in any one of claims 1-6, and a flipping mechanism. The first and second vision detection modules of the defect detection vision system are mounted above the conveyor line. The conveyor line drives the test sample to pass sequentially under the first and second vision detection modules. The flipping mechanism is located at one end of the conveyor line to flip the test sample.

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