Method and system for measuring the size of a lens pattern

Abstract

This invention provides a method and system for measuring the size of a lens pattern. [Solution] The method includes the steps of: using a printing module to form a lens including a pattern; using a camera module to acquire a lens image of the lens including the pattern, wherein the lens image includes a pattern image portion corresponding to the pattern; providing an annular mask unit on the lens image, wherein the annular mask unit covers the pattern image portion; and using an image analysis unit to perform at least one of steps (a) and (b), wherein step (a) is the step of determining an inner circle on the pattern image portion and calculating the diameter of the inner circle, and step (b) is the step of determining an outer circle on the pattern image portion and calculating the diameter of the outer circle, wherein the image analysis unit is connected to the camera module.

Description

Technical Field

[0001] The present disclosure relates to a method and system for measuring the size of a pattern, and more particularly, to a method and system for measuring the size of a pattern of a lens.

Background Art

[0002] Ophthalmic lenses such as contact lenses can be used to correct vision, treat diseases, and for cosmetic reasons. For example, the lens can include one or more patterns, which can be translucent or transparent and can at least partially cover a part of the eye to change the appearance of the user's eye. To ensure that the size of the pattern meets the specifications, it is necessary to measure the size of the pattern of the lens. One traditional measurement method is that an operator observes the pattern with his own eyes and measures the diameter of the pattern with a ruler. However, such a method depends on the operator who subjectively determines the position of the diameter of the pattern, and the measurement error varies according to the skill level of the operator. As a result, the repeatability is low, the reproducibility is low, and the measurement time is long. Another traditional measurement method is to obtain an image of the pattern of the lens by a microscope, and then the operator observes it with his own eyes and manually draws a circle similar to the pattern to obtain the diameter. However, such a method depends on the operator who subjectively determines the size and position of the circle, and the measurement error varies according to the skill level of the operator. The repeatability, reproducibility, and measurement time of the latter method have been improved compared with the former method, but the latter method is still not good enough to meet the market demand. Existing measurement methods often introduce errors that affect the lens yield by making it difficult to accurately reflect the quality of the pattern of the lens.

Prior Art Documents

Patent Documents

[0003] [Patent Document 1] Taiwan Patent Application Publication No. 202335652 [Patent Document 2] U.S. Patent Application Publication No. 2014 / 0099439 Specification [Overview of the project]

[0004] This disclosure relates to a method and system for measuring the size of a lens pattern that can reduce the need for subjective decisions by an operator, effectively reduce personal errors, and improve repeatability, reproducibility, and measurement time.

[0005] According to one embodiment of the present disclosure, a method for measuring the size of a pattern on a lens is provided. The method includes the steps of: using a printing module to form a lens including a pattern; using a camera module to acquire a lens image of the lens including the pattern, wherein the lens image includes a pattern image portion corresponding to the pattern; providing an annular mask unit on the lens image, wherein the annular mask unit covers the pattern image portion; and using an image analysis unit to perform at least one of steps (a) and (b), wherein step (a) is the step of determining an inner circle of the pattern image portion and calculating the diameter of the inner circle, and step (b) is the step of determining an outer circle of the pattern image portion and calculating the diameter of the outer circle, wherein the image analysis unit is connected to the camera module.

[0006] Embodiments of the present disclosure provide a system for measuring the size of a pattern on a lens. The system includes a printing module, a platform, a camera module, a light source module, and an image analysis unit. The printing module is for forming a lens including a pattern. The platform is for positioning the lens including the pattern. The camera module is for acquiring a lens image of the lens including the pattern. The lens image includes a pattern image portion corresponding to the pattern. The light source module includes a light source for supplying light to the lens including the pattern. The light source module and the camera module are positioned on opposite sides of the platform. An image analysis unit is connected to the camera module. The image analysis unit receives the lens image from the camera module, provides an annular mask unit covering the pattern image portion, and performs at least one of steps (a) and (b), where step (a) is the step of determining the inner circle of the pattern image portion and calculating the diameter of the inner circle, and step (b) is the step of determining the outer circle of the pattern image portion and calculating the diameter of the outer circle.

[0007] The embodiments described above and other embodiments of this disclosure will be better understood in relation to the following detailed description of non-limiting embodiments. The following description is made with reference to the accompanying drawings. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic diagram of a system according to one embodiment of the present disclosure for measuring the size of a lens pattern is shown. [Figure 2] A method according to one embodiment of this disclosure for measuring the size of a lens pattern is shown. [Figure 3A] A schematic diagram of a lens pattern according to one embodiment of this disclosure is shown. [Figure 3B] A schematic diagram of a lens pattern according to one embodiment of this disclosure is shown. [Figure 3C] A schematic diagram of a lens pattern according to one embodiment of this disclosure is shown. [Figure 3D] A schematic diagram of a lens pattern according to one embodiment of this disclosure is shown. [Figure 4] A schematic diagram of a lens image according to one embodiment of this disclosure is shown. [Modes for carrying out the invention]

[0009] The drawings may not necessarily be drawn to scale, and other embodiments of this disclosure that are not specifically shown may exist. Therefore, this specification and the drawings should be considered illustrative rather than restrictive. Furthermore, descriptions disclosed in embodiments of this disclosure, such as detailed structures, manufacturing processes, and material choices, are for illustrative purposes only and not intended to limit the scope of this disclosure. Processes and elements in the details of embodiments may be modified or altered according to the actual needs of a practical application. It is assumed that elements and features of one embodiment can be advantageously incorporated into another embodiment without further detail. This disclosure is not limited to the descriptions of these embodiments. In the drawings, the same / similar symbols are used to indicate the same / similar elements.

[0010] As used herein and in the appended claims, ordinal numbers such as “first,” “second,” etc., used to describe elements do not imply or represent a particular position in a structure, order of arrangement, or order of manufacture. Ordinal numbers are used solely to clearly distinguish multiple elements or components having the same name.

[0011] Refer to Figure 1. Figure 1 shows a schematic diagram of a system 100 according to one embodiment of the present disclosure for measuring the size of a lens pattern. The system 100 for measuring the size of a lens pattern includes a camera module 1, a platform 2, a light source module 3, an image analysis unit 4, a printing module 5, and a printing platform 6.

[0012] The camera module 1 can be a camera or a video camera. The platform 2 is used to position the lens L and includes a first surface 2U and a second surface 2B facing the first surface 2U. The first surface 2U of the platform 2 faces the camera module 1. The second surface 2B of the platform 2 faces the light source module 3. The lens L is positioned on the first surface 2U of the platform 2. In one embodiment, the lens L can be positioned in a container containing water or other suitable liquid, and together with the container, the lens L is positioned on the first surface 2U of the platform 2. In one embodiment, the lens L can be measured directly without being positioned in a liquid. In one embodiment, the convex surface of the lens L faces the camera module 1. In one embodiment, the concave surface of the lens L faces the camera module 1. The lens L includes a lens body LB and a pattern LP formed on the surface of the lens body LB. The platform 2 can be optically transparent or optically translucent. The camera module 1 can be used to acquire a lens image of the lens L including the pattern LP. The light source module 3 includes a light source 31 and a light source control unit 32. The light source 31 is connected to the light source control unit 32. The light source module 3 and the camera module 1 are arranged on opposite sides of the platform 2, thereby improving the imaging quality of the camera module 1. The light source 31 has a light-emitting surface 31S for emitting light. The light source 31 can supply light from the light-emitting surface 31S toward the lens L on the platform 2. The light source control unit 32 can be used to control the light source 31. The printing module 5 is used to form the lens L including the pattern LP. For example, the lens body LB to be printed on can be placed on the printing platform 6, and the printing module 5 moves toward the lens body LB, contacts the lens body LB, and transfers the pattern from the printing module 5 to the surface of the lens body, thereby forming the lens L including the pattern LP. The printing module 5 can be a pad printing device.

[0013] The image analysis unit 4 is connected to the camera module 1. The image analysis unit 4 can be used to receive lens images from the camera module 1 and can perform one or more operations on the lens image to obtain the size of pattern LP. For example, the image analysis unit 4 can be used to place an annular mask unit on the lens image, and / or the image analysis unit 4 can be used to optimize the lens image, and / or the image analysis unit 4 can be used to perform at least one of steps (a) and (b), where step (a) is the step of determining the inner circle of the pattern image portion and calculating the diameter of the inner circle, and step (b) is the step of determining the outer circle of the pattern image portion and calculating the diameter of the outer circle. For example, the image analysis unit 4 can be a processing unit. For example, the processing unit can be located in a computing device. In one embodiment, the image analysis unit 4 may include a verification module that can be used to verify whether the inner circle and the outer circle meet the specifications.

[0014] In one embodiment, a system 100 for measuring the size of a lens pattern can be used to perform a method 200 for measuring the size of a lens pattern, as shown in Figure 2. The method 200 for measuring the size of a lens pattern will be described below with reference to Figures 1-4. As shown in Figure 2, the method 200 may include steps S201, S203, S205, and S207.

[0015] Step S201: A printing module 5 is used to form a lens L containing a pattern LP. The lens L can be a hard contact lens or a soft contact lens. In one embodiment, the lens L is a silicone hydrogel contact lens. The pattern LP of the lens L is colored. When the lens L is placed on the surface of a human eye, the pattern LP of the lens L can at least partially cover the sclera and / or iris of the eye. The lens body LB can include an optical zone and a non-optical zone surrounding the optical zone. The optical zone can produce optical effects such as vision correction, and a person wearing the lens L can see through the optical zone. The pattern LP can be formed in the non-optical zone of the lens body LB. The pattern LP can have an annular shape and can surround the optical zone of the lens body LB. The pattern LP is not completely transparent. The pattern LP can consist of any number of dots and / or lines and / or color blocks to form various kinds of patterns. The dots and / or lines and / or color blocks of the pattern LP may be the same size or may be of different sizes. The dots and / or lines and / or color blocks of a pattern LP may have a variety of colors. A pattern LP can be a symmetrical pattern, an asymmetrical pattern, a pattern arranged in concentric circles, or a pattern arranged in non-concentric circles. The dots and / or lines and / or color blocks of a pattern LP can be arranged irregularly, i.e., some parts of the pattern differ from others, and as a result, rotating the pattern 90 degrees may make it appear different to the viewer. The dots and / or lines and / or color blocks of a pattern LP can be arranged regularly or evenly, and as a result, rotating the pattern 90 degrees may make little difference to the viewer. For example, a pattern LP can be a starburst pattern or a heart pattern. Figures 3A–3D show some possible patterns as examples, but this disclosure is not limited to them.

[0016] Step S203: The camera module 1 is used to acquire a lens image of lens L including pattern LP, such as lens image 50 as shown in Figure 4. Lens L can be photographed from either its convex or concave surface. The convex surface of lens L faces the concave surface of lens L. When lens L is placed on the surface of the eye, the concave surface of lens L faces the eye. Lens image 50 includes a pattern image portion 501 corresponding to pattern LP and a peripheral image portion 502 corresponding to the area other than pattern LP. In Figure 4, the annular image composed of dots (pixels) is the pattern image portion 501.

[0017] In one embodiment, when generating a lens image, the light source module 3 can be used to supply light to the lens L, which includes a pattern LP, thereby improving the imaging quality and the accuracy of subsequent measurements.

[0018] Step S205: An annular mask unit 52 is placed on the lens image 50. The lens image 50 generated by the camera module 1 can be transferred to the image analysis unit 4, which can place an annular mask unit 52 on the lens image 50. As shown in Figure 4, the annular mask unit 52 can be formed in the shape of a ring. Specifically, as shown in Figure 4, the annular mask unit 52 can be formed by two frame lines or composed of two frame lines (hereafter, these two frame lines will be represented by the inner frame line 521 and the outer frame line 522). The size of the inner frame line 521 is smaller than the size of the outer frame line 522. The inner frame line 521 and the outer frame line 522 are arranged so as not to overlap. The outer frame line 522 surrounds the inner frame line 521. The area covered by the annular mask unit 52 can be defined as a measurement area. The measurement area is located between the outer frame line 522 and the inner frame line 521. Areas not covered by the annular mask unit 52 are excluded areas, so that subsequent measurement steps can be avoided for portions of the lens image 50 in the excluded areas. Figure 4 shows that the inner frame line 521 and outer frame line 522 are circular, but the disclosure is not limited thereto. The annular mask unit 52 covers the pattern image portion 501. The annular mask unit 52 covers the entire pattern image portion 501. The annular mask unit 52 can be used to exclude or reduce noise in the lens image 50 so as to avoid or reduce the impact of noise on subsequent measurement steps. Noise in the lens image 50 may be caused by foreign matter such as dust or dandruff. For example, noise in the lens image 50 may be caused by foreign matter in the camera module 1, foreign matter on the lens L, or foreign matter in the liquid used to immerse the lens L.Noise in the lens image 50 (such as noise 54 as shown in Figure 4) may not be covered by the annular mask unit 52, i.e., all noise in the lens image 50 may be located in the exclusion region, or only the portion of the lens image 50 with little noise may be covered by the annular mask unit 52, i.e., most of the noise may be located in the exclusion region. The region covered by the annular mask unit 52 can be brought about according to a reference pattern. The reference pattern can be determined by the user. The annular mask unit 52 can be formed automatically by the image analysis unit 4, or it can be set manually by the user (e.g., the operator of the method and system described above). In one embodiment, the image analysis unit 4 can automatically set inner and outer frame lines on the lens image 50 according to the size of the reference pattern and the position of the reference pattern relative to the lens body LB in order to form the annular mask unit 52. For example, the user can pre-input parameters into the image analysis unit 4, which may include, but are not limited to, the size of the inner frame line, and / or the scaling ratio of the inner frame line to the size of the reference pattern, and / or the position of the inner frame line relative to the lens body LB, and / or the size of the outer frame line, and / or the scaling ratio of the outer frame line to the size of the reference pattern, and / or the position of the outer frame line relative to the lens body LB. The image analysis unit 4 can then automatically set the inner and outer frame lines on the lens image 50 based on the parameters set by the user to form an annular mask unit 52.In one embodiment, the image analysis unit 4 can be connected to a user interface device, and the lens image 50 generated by the camera module 1 can be transferred to the user interface device. The user can manually set inner and outer frame lines on the lens image 50 through the user interface device to form the annular mask unit 52. The types of the pattern LP shown in FIG. 4 and the shape and size of the annular mask unit 52 are merely examples, and the present disclosure can be adapted to various types of patterns, and the shape of the measurement region can be adjusted according to the type of the pattern to obtain better measurement results. The annular mask unit 52 can cover the entire pattern image portion 501 and a part of the peripheral image portion 502 (that is, the portion of the peripheral image portion 502 adjacent to the pattern image portion 501) to ensure that all the pattern image portions 501 are present in the measurement region. In one embodiment, the image analysis unit 4 can be connected to a display device, and the display device can display the user interface and the lens image 50.

[0019] In one embodiment, step S205 can further include a step of performing gray-scale processing by the image analysis unit 4 to convert the lens image 50 into a gray-scale image by the image analysis unit 4. Specifically, the lens image 50 is formed by a plurality of pixels each having a pixel value (for example, the pixel value can be represented by an R value, a G value, and a B value), and the gray-scale processing can convert the pixel value of each pixel into a gray-scale value. The gray-scale value can be any value between 0 and 255. In one embodiment, a gray-scale value of 0 means white, and a gray-scale value of 255 means black. In one embodiment, a gray-scale value of 255 means white, and a gray-scale value of 0 means black.

[0020] In one embodiment, step S205 may include the step of performing a binarization process on the lens image 50 to form a binary image after grayscale processing. The binary image is formed by a plurality of pixels, each pixel having only two possible values. For example, these two values ​​may be 0 and 1, or these two values ​​may be 0 and 255. The binarization process includes the step of setting a grayscale threshold in the range of 0 to 255. The binarization process may convert grayscale values ​​in a grayscale image greater than the grayscale threshold to one of 0 and 1, grayscale values ​​in a grayscale image less than the grayscale threshold to another of 0 and 1, and grayscale values ​​equal to the grayscale threshold to 0 or 1 as needed. Alternatively, the binarization process may convert grayscale values ​​in a grayscale image greater than the grayscale threshold to one of 0 and 255, grayscale values ​​in a grayscale image less than the grayscale threshold to another of 0 and 255, and grayscale values ​​equal to the grayscale threshold to 0 or 255 as needed. A grayscale threshold is available for use in the binarization process, and the method for converting grayscale values, which may be greater than or less than the grayscale threshold, can be determined by the user as needed. This disclosure is not limited to the embodiments described above. In one embodiment, step S205 may include grayscale processing and binarization processing, with the binarization processing performed after the grayscale processing, and the annular mask unit 52 may be provided before the grayscale processing or after the binarization processing. In one embodiment, step S205 includes grayscale processing but does not include binarization processing, and the annular mask unit 52 may be provided before the grayscale processing or after. In one embodiment, method 200 includes binarization processing but does not include grayscale processing, and the pixel value corresponding to each pixel of the lens image 50 can be converted to two possible values ​​through other pixel value conversion methods, and the annular mask unit 52 may be provided before the binarization processing or after.The use of grayscale processing and binarization processing is beneficial for image optimization and can improve the accuracy of subsequent measurements.

[0021] In one embodiment, step S205 may further include a step of performing noise reduction processing on a part of the lens image 50 in the measurement area after setting the annular mask unit 52 in order to remove noise from the lens image 50 so as to improve the accuracy of subsequent measurements. The noise reduction processing can be automatically performed by the image analysis unit 4 or manually performed by the user. The noise reduction processing can be performed after grayscale processing and binarization processing.

[0022] Step S207: Use the image analysis unit 4 to perform at least one of step (a) and step (b). Here, step (a) is a step of determining the inner circle 58 of the pattern image portion 501 in the measurement area and calculating the diameter ID of the inner circle 58 in the measurement area, and step (b) is a step of determining the outer circle 59 of the pattern image portion 501 and calculating the diameter OD of the outer circle 59. The pattern image portion 501 in the measurement area is formed by a plurality of pixels (hereinafter referred to as pattern pixels), the inner circle 58 is the largest circle surrounded by the plurality of pixels (pattern pixels), and the outer circle 59 is the smallest circle surrounding the plurality of pixels (pattern pixels). The inner circle 58 and the outer circle 59 can be determined by various methods. The methods for determining the inner circle 58 and the outer circle 59 will be described below by way of the first embodiment and the second embodiment as examples.

[0023] <The First Embodiment> Step (a) for determining the inner circle 58 may include the steps of: using the image analysis unit 4 to obtain a plurality of boundary points on the boundary of a plurality of pattern pixels, respectively; measuring the distance between each of these boundary points and the center point of the lens image 50; identifying at least two boundary points that are at the shortest distance from the center point of the lens image 50; and forming a circle using the at least two boundary points, which is the inner circle 58. In one embodiment, the at least two boundary points that are at the shortest distance from the center point of the lens image 50 are located on different pattern pixels. In one embodiment, these pattern pixels on which the at least two boundary points that are at the shortest distance from the center point of the lens image 50 are located circumscribe the inner circle 58. In one embodiment, the inner circle 58 is formed by two boundary points that are at the shortest distance from the center point of the lens image 50. In one embodiment, the inner circle 58 is formed by three boundary points that are at the shortest distance from the center point of the lens image 50.

[0024] Step (b) for determining the outer circle 59 may include the steps of: using the image analysis unit 4 to obtain a plurality of boundary points on the boundary of a plurality of pattern pixels, respectively; measuring the distance between each of these plurality of boundary points and the center point of the lens image 50; identifying at least two boundary points that are furthest from the center point of the lens image 50; and forming a circle using the at least two boundary points, which is the outer circle 59. In one embodiment, the at least two boundary points that are furthest from the center point of the lens image 50 are located on different pattern pixels. In one embodiment, these pattern pixels on which the at least two boundary points that are furthest from the center point of the lens image 50 are located are inscribed in the outer circle 59. In one embodiment, the outer circle 59 is formed by two boundary points that are furthest from the center point of the lens image 50. In one embodiment, the outer circle 59 is formed by three boundary points that are furthest from the center point of the lens image 50.

[0025] <Second Embodiment> Step (a) for determining the inner circle 58 may include: using the image analysis unit 4 to perform edge detection on the pattern image portion 501 in a measurement area to form an inner edge of the pattern image portion 501 along the boundary of the pattern pixels; using the image analysis unit 4 to obtain a plurality of edge points on the inner edge; measuring the distance between each of these plurality of edge points and the center point of the lens image 50; identifying at least two edge points that are at the shortest distance from the center point of the lens image 50; and forming a circle using the at least two edge points, which is the inner circle 58. In one embodiment, the inner circle 58 is formed by two edge points that are at the shortest distance from the center point of the lens image 50. In one embodiment, the inner circle 58 is formed by three edge points that are at the shortest distance from the center point of the lens image 50.

[0026] Step (b) for determining the outer circle 59 may include: using the image analysis unit 4 to perform edge detection on the pattern image portion 501 in a measurement area to form an outer edge of the pattern image portion 501 along the boundary of the pattern pixels; using the image analysis unit 4 to obtain a plurality of edge points on the outer edge; measuring the distance between each of these plurality of edge points and the center point of the lens image 50; identifying at least two edge points that are at the maximum distance from the center point of the lens image 50; and forming a circle using the at least two edge points, which is the outer circle 59. In one embodiment, the outer circle 59 is formed by two edge points that are at the maximum distance from the center point of the lens image 50. In one embodiment, the outer circle 59 is formed by three edge points that are at the maximum distance from the center point of the lens image 50. The inner and outer edges of the pattern image portion 501 may include a portion of the boundary of the pattern pixels. The inner and outer edges of the pattern image portion 501 may also include line segments that connect the boundaries of adjacent pattern pixels. Therefore, the edge points used to form the inner circle 58 and the outer circle 59 are located on the inner and outer edges, respectively, but do not necessarily lie on the boundaries of the pattern pixels (i.e., they may lie on line segments connecting the boundaries of adjacent pattern pixels).

[0027] In the first and second embodiments, the above steps for determining the inner circle 58 and the outer circle 59 can be performed simultaneously or in any order.

[0028] The method for determining the inner circle 58 may be the same as or different from the method for determining the outer circle 59. For example, the inner circle 58 may be determined by one of the methods described in the first and second embodiments, and the outer circle 59 may be determined by another of the methods described in the first and second embodiments. Alternatively, the inner circle 58 and the outer circle 59 may be determined by one of the methods described in the first and second embodiments.

[0029] In one embodiment, step S207 may include a verification step. The verification step includes verifying whether, after determining the inner circle 58, all of the multiple pixels of the pattern image portion 501 in the measurement area are outside the inner circle 58, and / or after determining the outer circle 59, verifying whether the outer circle 59 surrounds each of the above multiple pixels of the pattern image portion 501 in the measurement area. The verification step may be performed by the image analysis unit 4, or alternatively, the verification step may be performed through visual observation by the user. Depending on the failure of the verification, steps S203, S205, and S207, steps S205 and S207, or just step S207 may be re-executed.

[0030] The above steps S201, S203, S205, and S207 can be performed in any order. Other steps may be included before, between, and after steps S201, S203, S205, and S207.

[0031] The measurement results according to this disclosure will be explained with reference to examples and comparative examples. Lenses containing the patterns shown in Figures 3A to 3D are provided. In embodiments 1 to 4, each lens is measured 10 times using the same process to obtain 10 values ​​of the inner circle diameter and 10 values ​​of the outer circle diameter. The difference between the maximum and minimum values ​​of the 10 outer circle diameters for the same lens is calculated and listed in Table 1 as a diameter variable. Similarly, the difference between the maximum and minimum values ​​of the 10 inner circle diameters for the same lens is calculated and also listed in Table 1.

[0032] Comparative Examples 1-4 utilize conventional measurement methods to measure the size of the patterns shown in Figures 3A-3D. In Comparative Examples 1-4, each lens is measured 10 times using the same steps. Specifically, images of the patterns shown in Figures 3A-3D are acquired using a microscope, and an operator manually draws circles approximating the pattern images by visual observation to obtain 10 values ​​for the diameter of the inner circle and 10 values ​​for the diameter of the outer circle. The difference between the maximum and minimum values ​​of the 10 outer circle diameters for the same lens is calculated and listed as a diameter variable in Table 1. Similarly, the difference between the maximum and minimum values ​​of the 10 inner circle diameters for the same lens is calculated and listed in Table 1.

[0033] [Table 1]

[0034] As shown in Table 1, the diameter differences in Examples 1-4 are all 0.06 or less, meaning that the method of measuring the size of a lens pattern according to this disclosure has good repeatability and good reproducibility, and stable measurement results with small errors. The diameter differences in Comparative Examples 1-4 all exceed 0.06, and can even reach 0.25. This means that the measurement results obtained by traditional measurement methods are very variable and unstable, and the repeatability and reproducibility of traditional measurement methods are far lower than those of the method of this disclosure. The method and system of this disclosure for measuring the size of a lens pattern can obtain the diameter through an automated measurement method, which can greatly reduce errors caused by the skill level of the operator, effectively shorten measurement time, and reduce the defect rate of lenses. In addition, in traditional measurement methods, when foreign matter is present in the system, the operator often mistakes the image of the foreign matter (i.e., noise) for part of the pattern, resulting in measurement errors. The method and system of this disclosure for measuring the size of a lens pattern uses an annular mask unit to define the measurement area, which allows for the removal of noise in the image caused by foreign matter before the inner and outer circles are formed. Thus, errors caused by the operator's skill level can be reduced, and measurement accuracy can be improved.

[0035] While this disclosure is described in terms of examples and (multiple) exemplary embodiments, it should be understood that this disclosure is not limited thereto. Rather, it is intended to include a variety of modifications and similar arrangements and procedures, and therefore the scope of the appended claims should be given the broadest interpretation to include all such modifications and similar arrangements and procedures.

Claims

1. A method for measuring the size of a lens pattern, The aforementioned method, A process of using a printing module to form a lens containing a pattern, A step of using a camera module to acquire a lens image of the lens including the pattern, wherein the lens image includes a pattern image portion corresponding to the pattern; A step of providing an annular mask unit on the lens image, wherein the annular mask unit covers the pattern image portion. A step of using an image analysis unit to perform at least one of steps (a) and (b), wherein step (a) is a step of determining an inner circle on the pattern image portion and calculating the diameter of the inner circle, and step (b) is a step of determining an outer circle on the pattern image portion and calculating the diameter of the outer circle, Includes, The image analysis unit is connected to the camera module. method.

2. The method according to claim 1, further comprising the step of performing a binarization process using the image analysis unit.

3. The method according to claim 1, wherein the annular mask unit is formed by an outer frame line and an inner frame line, the outer frame line surrounds the inner frame line, and the region covered by the annular mask unit is a measurement region located between the outer frame line and the inner frame line.

4. The method according to claim 1, wherein the region covered by the annular mask unit is provided according to a reference pattern.

5. The method according to claim 1, wherein the pattern image portion is formed by a plurality of pixels, the outer circle is the smallest circle surrounding the plurality of pixels, and the inner circle is the largest circle surrounded by the plurality of pixels.

6. A step of confirming that the outer circle surrounds each of the plurality of pixels, and a step of confirming that all of the plurality of pixels are outside the inner circle. The method according to claim 5, further comprising:

7. A step of using a light source module to supply light to the lens including the pattern, wherein the lens including the pattern is positioned between the light source module and the camera module, The method according to claim 1, further comprising:

8. Step (a) above is, The steps include: performing edge detection on the pattern image portion in order to determine the inner edges of the pattern image portion; The steps include: using the image analysis unit to obtain a plurality of edge points on the inner edge; measuring the distance between each of the plurality of edge points and the center point of the lens image; identifying at least two edge points that are the shortest distance from the center point of the lens image; and forming the inner circle using the at least two edge points. including, or Step (a) above is, A step of using the image analysis unit to obtain a plurality of boundary points on the boundary of a plurality of pixels in the pattern image portion, wherein the pattern image portion is formed by the plurality of pixels, The steps include measuring the distance between each of the plurality of boundary points and the center point of the lens image, identifying at least two boundary points that are the shortest distance from the center point of the lens image, and forming the inner circle using the at least two boundary points, including, The method according to claim 1.

9. Step (b) above is: The steps include: performing edge detection on the pattern image portion in order to determine the outer edge of the pattern image portion; The steps include: using the image analysis unit to obtain a plurality of edge points on the outer edge; measuring the distance between each of the plurality of edge points and the center point of the lens image; identifying at least two edge points that are at the maximum distance from the center point of the lens image; and forming the outer circle using the at least two edge points. including, or Step (b) above is: A step of using the image analysis unit to obtain a plurality of boundary points on the boundary of a plurality of pixels in the pattern image portion, wherein the pattern image portion is formed by the plurality of pixels, The steps include measuring the distance between each of the plurality of boundary points and the center point of the lens image, identifying at least two boundary points that are the furthest from the center point of the lens image, and forming the outer circle using the at least two boundary points, including, The method according to claim 1.

10. A system for measuring the size of a lens pattern, A printing module for forming a lens containing a pattern, A platform for arranging the lens including the pattern, A camera module for acquiring a lens image of the lens having the pattern, wherein the lens image includes a pattern image portion corresponding to the pattern, A light source module comprising a light source for supplying light to the lens including the pattern, wherein the light source module and the camera module are arranged on opposite sides of the platform, An image analysis unit connected to the camera module, which receives the lens image from the camera module, is provided with an annular mask unit that covers the pattern image portion, and performs at least one of the following steps: (a) determining an inner circle on the pattern image portion and calculating the diameter of the inner circle, and (b) determining an outer circle on the pattern image portion and calculating the diameter of the outer circle. A system that includes these features.

Images