Lens imaging quality detection system and detection method thereof

Abstract

The invention discloses a lens imaging quality detection system and a detection method thereof, the detection system comprises a target, an image acquisition unit, an image analysis unit and a display unit, the target comprises a mobile platform, a light source and an industrial resolution plate, the industrial resolution plate comprises at least two types of line pair groups, and the line pair groups of the industrial resolution plate are determined according to a to-be-detected lens; wherein the mobile platform is used for adjusting the position of the industrial resolution ratio plate, so that the plane of the industrial resolution ratio plate is parallel to a to-be-tested lens, and the center of the industrial resolution ratio plate is overlapped with the center of the to-be-tested lens; the image acquisition unit is used for acquiring an image of the industrial resolution plate after passing through the to-be-detected lens; the image analysis unit is used for determining the definition according to the image and determining the imaging quality of the to-be-detected lens according to the definition; and the display unit is used for displaying the definition curve and the imaging quality of the to-be-measured lens. The embodiment of the invention can quickly detect the imaging quality of the to-be-detected lens, and can be widely applied to the technical field of detection.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to a lens imaging quality detection system and a detection method thereof. Background Art

[0002] Image quality is a key parameter used to evaluate the performance of an imaging optical system. Image quality refers to the consistency of the intensity and color space distribution between the image and the object, regardless of magnification—in other words, the fidelity of the image to the object. Resolution testing is a key parameter used to evaluate the quality of an imaging optical system. Resolution, also known as resolving power, discrimination, analytical power, or resolving power, refers to the camera module's ability to clearly reproduce details of the captured scene.

[0003] With the development of the optical industry, higher requirements have been placed on the image clarity, object-image similarity, and degree of distortion produced by optical systems. This increased demand for imaging quality requires higher precision requirements for lenses and related items. However, this increased precision is not only limited by current processing technology but also increases production costs. Therefore, in order to reduce production costs, a method for rapidly evaluating lens imaging quality during production is urgently needed to correct for aberrations caused by the accumulated tolerances of material combinations, thereby improving imaging quality, reducing defect rates, and reducing enterprise costs. Summary of the Invention

[0004] In view of this, in order to solve one of the above problems, an embodiment of the present invention aims to provide a lens imaging quality detection system and a detection method thereof, which can quickly detect the imaging quality of a lens to be tested.

[0005] In one aspect, an embodiment of the present invention provides a lens imaging quality detection system, comprising a target, an image acquisition unit, an image analysis unit, and a display unit. The target comprises a mobile platform, a light source, and an industrial resolution plate. The industrial resolution plate comprises at least two types of line pair groups. The line pair groups of the industrial resolution plate are determined according to the lens to be tested.

[0006] The movable platform is used to adjust the position of the I-resolution plate so that the plane of the I-resolution plate is parallel to the image plane of the lens to be tested and the center of the I-resolution plate overlaps with the center of the lens to be tested;

[0007] The image acquisition unit is used to acquire the image of the high-resolution plate after passing through the lens to be tested;

[0008] The image analysis unit is used to determine the clarity of the image and determine the imaging quality of the lens to be tested based on the clarity;

[0009] The display unit is used to display the clarity curve and imaging quality of the lens to be tested.

[0010] Optionally, the sizes of the various line pair groups of the high-resolution panel are different, and the various line pair groups are cross-distributed.

[0011] Optionally, the imaging quality includes qualified and unqualified, and the qualified includes several quality levels.

[0012] Optionally, the various line pair groups of the high-resolution panel include black blocks, the clarity index includes a modulation transfer function, and the image analysis unit is configured to:

[0013] determining a target black block according to the image, determining a first brightness according to the target black block; and determining a second brightness according to the background of the image;

[0014] determining a point set of an area of ​​interest according to the image, and determining a third brightness and a fourth brightness according to a grayscale value set of the point set;

[0015] A modulation transfer function is obtained according to the first brightness, the second brightness, the third brightness, and the fourth brightness.

[0016] Optionally, determining a point set of an area of ​​interest according to the image includes:

[0017] Determine an offset according to the center of the image and the center of the target line pair group; the center of the target line pair group is determined according to the target black block;

[0018] A point set of an area of ​​interest is determined according to the target line pair group of the high-resolution plate and the offset.

[0019] Optionally, determining the third brightness and the fourth brightness according to the grayscale value set of the point set includes:

[0020] Calculating a first average grayscale value of the region of interest based on the grayscale value set of the point set;

[0021] The point set with grayscale values ​​greater than the first average grayscale value is taken as a first set, and the second average grayscale value of the first set is taken as a third brightness;

[0022] A point set with grayscale values ​​less than the first average grayscale value is taken as a second set, and a third average grayscale value of the second set is taken as a fourth brightness.

[0023] Optionally, obtaining a modulation transfer function according to the first brightness, the second brightness, the third brightness, and the fourth brightness includes:

[0024] performing a first operation on the first brightness and the second brightness to obtain a first value;

[0025] performing a second operation on the third brightness and the fourth brightness to obtain a second value;

[0026] A third operation is performed on the first value and the second value to obtain a modulation transfer function.

[0027] Optionally, the clarity index includes a modulation transfer function, and determining the imaging quality of the lens to be tested according to the clarity includes:

[0028] determining whether the modulation transfer function is within a preset range;

[0029] If the modulation transfer function is within a preset range, determining the quality level of the lens to be tested according to the modulation transfer function and a preset comparison relationship;

[0030] If the modulation transfer function is not within a preset range, it is determined that the lens to be tested is unqualified.

[0031] Optionally, the display unit is used to:

[0032] Different colors are used to display the test results of lenses with different quality levels.

[0033] On the other hand, an embodiment of the present invention provides a detection method of a lens imaging quality detection system, comprising:

[0034] Install the lens to be tested at a preset position of the image acquisition unit;

[0035] Focusing is performed according to a first preset speed, if the display unit displays clarity;

[0036] Focusing is performed according to a second preset speed, and the display unit displays the imaging quality.

[0037] The implementation of the embodiment of the present invention includes the following beneficial effects: the lens imaging quality detection system in this embodiment includes a target, an image acquisition unit, an image analysis unit and a display unit, the target includes a mobile platform, a light source and an industrial resolution board, the industrial resolution board includes at least two types of line pair groups, the line pair group of the industrial resolution board is determined according to the lens to be tested, the position of the industrial resolution board is adjusted by the mobile platform to adjust the center and parallel plane of the lens to be tested, the image of the industrial resolution board after passing through the lens to be tested is obtained by the image acquisition unit, the clarity is determined according to the image by the image analysis unit and the imaging quality of the lens to be tested is determined according to the clarity, the clarity curve and imaging quality of the lens to be tested are displayed by the display unit, manual participation is reduced, and the degree of automation is high, so that the imaging quality of the lens to be tested can be quickly detected; in addition, multiple groups of line pairs are merged into one industrial resolution board, which saves costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 1 is a structural diagram of a lens imaging quality detection system provided by an embodiment of the present invention;

[0039] Figure 2 An image of a high-resolution plate provided by an embodiment of the present invention;

[0040] Figure 3 A target coordinate system and an image coordinate system provided by an embodiment of the present invention;

[0041] Figure 4 is a schematic structural diagram of a region of interest provided by an embodiment of the present invention;

[0042] Figure 5 The present invention provides a flowchart of the steps of a detection method of a lens imaging quality detection system. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are provided for ease of description only and do not limit the order of the steps. The order of execution of the steps in the embodiments can be adaptively adjusted based on the understanding of those skilled in the art.

[0044] The following is an explanation of professional terms.

[0045] MTF (Modulation Transfer Function) is used to evaluate the resolving power of a lens.

[0046] LP (Line pairs) is a term used in the field of film, lenses, and other cinematography. Line pairs per millimeter generally refers to the unit of resolution, indicating how many line pairs an instrument can distinguish within one millimeter.

[0047] ROI (region of interest).

[0048] like Figure 1 As shown, an embodiment of the present invention provides a lens imaging quality detection system, including a target, an image acquisition unit, an image analysis unit and a display unit. The target includes a mobile platform, a light source and an industrial resolution board. The industrial resolution board includes at least two types of line pair groups. The line pair groups of the industrial resolution board are determined according to the lens to be tested.

[0049] A mobile platform is used to adjust the position of the I-resolution plate so that the plane of the I-resolution plate is parallel to the image plane of the lens to be tested and the center of the I-resolution plate overlaps with the center of the lens to be tested;

[0050] An image acquisition unit, used to acquire an image of the high-resolution plate after it passes through the lens to be tested;

[0051] An image analysis unit, configured to determine the clarity of the image and determine the imaging quality of the lens to be tested based on the clarity;

[0052] The display unit is used to display the clarity curve and imaging quality of the lens to be tested.

[0053] The light source includes, but is not limited to, a white backlight source. The brightness of each backlight source is controlled at approximately 200 grayscale values. The distance between the lens and the target (i.e., the lens working distance) can be measured using a grating ruler and can be manually adjusted. The mobile platform is mounted at the bottom of the target. The image acquisition unit includes, but is not limited to, a camera or video camera, and the lens to be tested is mounted on the image acquisition unit. The image analysis unit includes, but is not limited to, a terminal with a processor, such as a server. The display unit includes, but is not limited to, a device with a display function, such as a display screen.

[0054] See Figure 2 The same line pair passing through lenses of different magnifications represents a different number of line pairs. Each lens requires a corresponding industrial resolution board based on its magnification. To save costs, the industrial resolution boards corresponding to two lenses are combined, meaning each lens has one industrial resolution board.

[0055] Specifically, an I / O resolution plate is placed on a mobile platform, and the lens to be tested is mounted on an image acquisition unit. The mobile platform is adjusted to ensure that the center of the I / O resolution plate overlaps with the center of the lens to be tested, and that the plane of the I / O resolution plate is parallel to the lens to be tested. Light from a light source passes through the I / O resolution plate and the lens to be tested, forming an image in the image acquisition unit. The image analysis unit analyzes the image and determines the image quality of the lens to be tested based on the clarity. The display unit displays the clarity curve and image quality of the lens to be tested.

[0056] Optionally, the sizes of the various line pair groups of the high-resolution board are different, and the various line pair groups are cross-distributed.

[0057] See Figure 2 For example, an I2C board with two types of line pair groups is displayed. Each board has two line pair groups, one large and one small, interlaced. Four black blocks, two of the same size, are symmetrically placed around the center of the board. The black blocks are used to measure the board's darkness, center brightness, and rotation angle. Circles of varying radius represent different fields of view, with the centers of each line pair group positioned at different locations in the field of view.

[0058] The principle behind distinguishing different line pair shapes on the same industrial resolution board is to identify the black block corresponding to the line pair shape based on a predetermined area, and then determine the angle and field of view distance for each line pair. For lenses with different magnifications, the image size of the corresponding line pair pattern is consistent. That is, a small line pair pattern corresponds to a high-magnification lens, and a large line pair pattern corresponds to a low-magnification lens. Therefore, black blocks are screened based on a specific area range, and then the angles and area of ​​the line pair group in other directions are determined based on the black blocks, ultimately identifying the corresponding line pair shape. Combining the two lens targets can reduce the number of industrial resolution boards and fixtures, thereby lowering inspection costs.

[0059] Optionally, the imaging quality includes qualified and unqualified, and qualified includes several quality levels.

[0060] The imaging quality of the lens to be tested is divided into qualified and unqualified according to the image judgment standard, and the qualified products are further divided into different quality grades. The number of quality grades is determined according to actual application and is not specifically limited in this embodiment.

[0061] Optionally, the various line pair groups of the high-resolution panel include black blocks, the clarity index includes a modulation transfer function, and the image analysis unit is used to:

[0062] Determine a target black block according to the image, determine a first brightness according to the target black block; and determine a second brightness according to the background of the image;

[0063] Determine a point set of the region of interest according to the image, and determine a third brightness and a fourth brightness according to a grayscale value set of the point set;

[0064] A modulation transfer function is obtained according to the first brightness, the second brightness, the third brightness, and the fourth brightness.

[0065] The target black block refers to the black block in the line pair group corresponding to the lens to be tested in the industrial resolution plate, the third brightness refers to the brightness corresponding to the point set that meets the preset requirements in the area of ​​interest, and the fourth brightness refers to the brightness corresponding to the remaining point sets in the area of ​​interest.

[0066] The target black block is obtained by performing binarization, opening operation, contour recognition, contour filling, contour screening and other operations on the image, and the grayscale value of the target black block area is used as the first brightness. The brightness of the white background next to the line pair group is read on the image as the second brightness. The coordinates of the point set of the area of ​​interest are determined according to the image, the image corresponding to the point set is determined according to the coordinates of the point set of the area of ​​interest, the third point set and the fourth point set are determined according to the image corresponding to the point set and the preset requirements, the third brightness is determined according to the third point set, and the fourth brightness is determined according to the fourth point set. The modulation transfer function is obtained according to the first brightness, the second brightness, the third brightness and the fourth brightness and the preset calculation formula. It should be noted that the preset calculation formula is determined according to the actual application and is not specifically limited in this embodiment.

[0067] Optionally, determining a point set of a region of interest according to an image includes:

[0068] The offset is determined based on the center of the image and the center of the target line pair group; the center of the target line pair group is determined based on the target black block;

[0069] The point set of the area of ​​interest is determined based on the target line pair group and offset of the high-resolution plate.

[0070] To calculate the MTF value of a lens under test, we first need to find the exact positions of the relevant line pairs in the camera image. In this MTF system, there are two coordinate systems: one representing the coordinates of the target's design drawing, and the other representing the coordinates of the image captured by the camera.

[0071] In the target design's coordinate system, the target center is the origin. The coordinates of all other objects, including the large and small black blocks, the line pair ROIs, and each line pair, are known. Alternatively, the distances of these objects from the center, as well as the angles between the lines connecting each point and the center and the horizontal, are all known.

[0072] The relationship between the target captured by the camera and the actual target includes the following aspects: horizontal and vertical offsets (x, y); rotation offset Δθ around the midpoint of the camera image; and image magnification ratio k produced by lens imaging.

[0073] See Figure 3 The black coordinate system (X2 / Y2) is the camera image coordinate system, and the blue coordinate system (X1 / Y1) is the target design coordinate system. The red dot (O1) is the center point of the target captured by the camera, and the green dot (M) is any point on the target.

[0074] Assuming that the coordinates of the green point (M) in the design drawing are (xt, yt), the actual distance between point M and the target center can be calculated The angle between the line connecting point M and the point in the target design diagram and the horizontal line is Δθt.

[0075] Assume that the coordinates of the red point (O1) in the camera image coordinate system are (x, y) and the zoom ratio of the lens is k; then, the coordinates (X, Y) of the green point (M) in the camera coordinate system are:

[0076] X=x+k·L·cos(Δθ+Δθt)

[0077] Y=y+k·L·sin(Δθ+Δθt)

[0078] Where k represents the magnification ratio, and L represents the straight-line distance between point O1 and point M.

[0079] P1 and P2 are the midpoints of a black line in the target. If the slope of the line connecting P1 and P2 is... For example, if P1 is (2, 2) and P2 is (9, 11), the coordinate difference PS between P1 and P2 is (7, 9), and the coordinate difference unit is PO(7 / 9, 1). Each point on the line segment between P1 and P2 has a horizontal coordinate of Xn = 2 + n * 7 / 9 and a vertical coordinate of Yn = 2 + n. Then, add n (0-9) times PO to P1. Because the entire black line is more than one pixel wide, the points corresponding to the calculated coordinates of the line segment connecting P1 and P2 are marked in red. Similarly, other parts of the black line can be marked with other colors, such as blue or yellow. While the lines are theoretically parallel, in practice, due to rounding, some points will overlap (point P represents the overlapping portion). Because of this duplication, the point set in the ROI area must be deduplicated.

[0080] Optionally, determining the third brightness and the fourth brightness according to the grayscale value set of the point set includes:

[0081] Calculate a first average gray value of the region of interest based on the gray value set of the point set;

[0082] The point set with grayscale values ​​greater than the first average grayscale value is taken as the first set, and the second average grayscale value of the first set is taken as the third brightness;

[0083] The point set with grayscale values ​​less than the first average grayscale value is taken as the second set, and the third average grayscale value of the second set is taken as the fourth brightness.

[0084] Specifically, based on the acquired set of ROI grayscale values, the first average grayscale value of the set of ROI grayscale values ​​is calculated. The portion greater than the first average grayscale value is recorded as set A, and the portion less than the first average grayscale value is recorded as set B. The grayscale values ​​of the point set in set A are averaged to obtain the second average grayscale value, which is recorded as the third brightness. The grayscale values ​​of the point set in set B are averaged to obtain the third average grayscale value, which is recorded as the fourth brightness.

[0085] Optionally, obtaining a modulation transfer function according to the first brightness, the second brightness, the third brightness, and the fourth brightness includes:

[0086] Perform a first operation on the first brightness and the second brightness to obtain a first value;

[0087] performing a second operation on the third brightness and the fourth brightness to obtain a second value;

[0088] A third operation is performed on the first value and the second value to obtain a modulation transfer function.

[0089] It should be noted that the first operation, the second operation, and the third operation are determined according to actual applications and are not specifically limited in this embodiment. The first operation, the second operation, and the third operation include, but are not limited to, any one or more of addition, subtraction, multiplication, and division. In a specific embodiment, the modulation transfer function is calculated using the following formula.

[0090] MTF=(imax–imin) / (IMAX-IMIN)*pi / 4

[0091] Wherein, MTF represents modulation transfer function, IMIN represents the first brightness, IMAX represents the second brightness, imax represents the third brightness, and imin represents the fourth brightness.

[0092] Optionally, the clarity index includes a modulation transfer function, and determining the imaging quality of the lens to be tested based on the clarity includes:

[0093] determining whether the modulation transfer function is within a preset range;

[0094] If the modulation transfer function is within a preset range, determining the quality level of the lens to be tested according to the modulation transfer function and the preset comparison relationship;

[0095] If the modulation transfer function is not within the preset range, it is determined that the lens to be tested is unqualified.

[0096] The preset range is determined based on actual application and is not specifically limited in this embodiment. The preset range is determined based on the measurement indicators of the lens under test, with different measurement indicators corresponding to different preset ranges. The preset comparison relationship refers to the comparison relationship between the modulation transfer function and the quality level of the lens under test. The preset comparison relationship is determined based on actual application and is not specifically limited in this embodiment, such as a comparison relationship table or comparison relationship formula.

[0097] Specifically, whether the imaging quality of the lens to be tested is qualified is determined according to the modulation transfer function and a preset range. If the imaging quality of the lens to be tested is qualified, the quality level of the lens to be tested is determined according to the modulation transfer function and a preset comparison relationship.

[0098] Optionally, the display unit is used to:

[0099] Different colors are used to display the test results of lenses with different quality levels.

[0100] Different colors are used to display the test results of lenses with different quality levels, so that users can more easily distinguish the quality of the lenses to be tested. For example, green, blue, yellow or purple are used to display lenses with different levels among qualified products, and red is used to display unqualified lenses to be tested.

[0101] In a specific embodiment, the main tasks of the image analysis unit and the display unit include:

[0102] The image analysis unit receives the image sent by the image acquisition unit, and displays the image in the image display frame in real time through the display unit.

[0103] The image analysis unit calculates the clarity of the line pair groups captured in the image in real time, that is, the MTF (Modulation Transfer Function) curve.

[0104] The display unit displays the clarity calculation result near the line pair group.

[0105] The display unit displays the calculated MTF (Modulation Transfer Function) curves of all line pair groups in different colors in the curve display box on the right.

[0106] During the focusing process, the display unit automatically records the best MTF (Modulation Transfer Function) picture.

[0107] The image analysis unit determines whether the overall imaging quality of the lens is qualified.

[0108] The image analysis unit analyzes the image information of the line pair group and calculates the MTF (Modulation Transfer Function) curve of the image imaging in the line pair group area. The MTF (Modulation Transfer Function) curve can be used to evaluate the imaging quality of the lens near the diagonal area under test.

[0109] The system allows operators to preset the MTF (Modulation Transfer Function) calculation specifications for each target line pair for each lens model. When the MTF curves for all target line pairs meet the specifications, a letter grade is displayed in various background colors. If any target line pair fails to meet the specifications, "NG" is displayed in red. Line pairs that fail the specifications are indicated by red numbers near the hypotenuse, allowing operators to quickly and easily determine whether the image quality of the tested lens is acceptable.

[0110] See Figure 5 The embodiment of the present invention provides a detection method of a lens imaging quality detection system, comprising:

[0111] S210, installing the lens to be tested at a preset position of the image acquisition unit;

[0112] S220, focusing according to a first preset speed, if the display unit shows clarity;

[0113] S230 , focusing is performed according to a second preset speed, and the display unit displays the imaging quality.

[0114] The embodiment of the present invention provides a testing device suitable for testing the imaging quality of industrial lenses during mass production. The overall steps of the single lens testing process are few and quick.

[0115] After the preparation work before testing is completed, the process of continuous testing is as follows:

[0116] Step 1: Take a lens to be inspected and quickly screw it into the image acquisition unit (camera) until it is tightened.

[0117] Step 2: Quickly rotate the focus knob while observing the image on the display until it approaches the focus point. At this point, the MTF (Modulation Transfer Function) curve will appear and continuously update, using the Modulation Transfer Function to characterize clarity.

[0118] Step 3: Slowly rotate the focus knob, observing the MTF (Modulation Transfer Function) value and the lens rating in the software interface. The system will automatically record the best MTF (Modulation Transfer Function) image and rating.

[0119] Step 4: If the lens rating appears, it means the lens image quality is acceptable. If the lens rating does not appear after rotating beyond the clearest point, it means the lens image quality is unacceptable.

[0120] Step 5: Quickly rotate to remove the lens and proceed to the next lens inspection.

[0121] The entire process can be completed within 30 seconds, with fast detection speed and low requirements for operators.

[0122] The implementation of the embodiment of the present invention includes the following beneficial effects: the lens imaging quality detection system in this embodiment includes a target, an image acquisition unit, an image analysis unit and a display unit, the target includes a mobile platform, a light source and an industrial resolution board, the industrial resolution board includes at least two types of line pair groups, the line pair group of the industrial resolution board is determined according to the lens to be tested, the position of the industrial resolution board is adjusted by the mobile platform to adjust the center and parallel plane of the lens to be tested, the image of the industrial resolution board after passing through the lens to be tested is obtained by the image acquisition unit, the clarity is determined according to the image by the image analysis unit and the imaging quality of the lens to be tested is determined according to the clarity, the clarity curve and imaging quality of the lens to be tested are displayed by the display unit, manual participation is reduced, and the degree of automation is high, so that the imaging quality of the lens to be tested can be quickly detected; in addition, multiple groups of line pairs are merged into one industrial resolution board, which saves costs.

[0123] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A lens imaging quality detection system, characterized in that: The device comprises a target, an image acquisition unit, an image analysis unit and a display unit. The target comprises a mobile platform, a light source and an industrial resolution plate. The industrial resolution plate comprises at least two types of line pair groups. The line pair groups of the industrial resolution plate are determined according to the lens to be tested. The movable platform is used to adjust the position of the I-resolution plate so that the plane of the I-resolution plate is parallel to the image plane of the lens to be tested and the center of the I-resolution plate overlaps with the center of the lens to be tested; The image acquisition unit is used to acquire the image of the high-resolution plate after passing through the lens to be tested; The image analysis unit is used to determine the clarity of the image and determine the imaging quality of the lens to be tested based on the clarity; The display unit is used to display the clarity curve and imaging quality of the lens to be tested.

2. The detection system according to claim 1, characterized in that The sizes of the various line pair groups of the high-resolution board are different, and the various line pair groups are cross-distributed.

3. The detection system according to claim 1, characterized in that The imaging quality includes qualified and unqualified, and the qualified includes several quality levels.

4. The detection system according to any one of claims 1 to 3, characterized in that: The various line pair groups of the high-resolution panel include black blocks, the clarity index includes a modulation transfer function, and the image analysis unit is used to: determining a target black block according to the image, determining a first brightness according to the target black block; and determining a second brightness according to the background of the image; determining a point set of an area of ​​interest according to the image, and determining a third brightness and a fourth brightness according to a grayscale value set of the point set; A modulation transfer function is obtained according to the first brightness, the second brightness, the third brightness, and the fourth brightness.

5. The detection system according to claim 4, characterized in that: The step of determining a point set of an area of ​​interest according to the image comprises: Determine an offset according to the center of the image and the center of the target line pair group; the center of the target line pair group is determined according to the target black block; A point set of an area of ​​interest is determined according to the target line pair group of the high-resolution plate and the offset.

6. The detection system according to claim 4, characterized in that: The determining the third brightness and the fourth brightness according to the grayscale value set of the point set includes: Calculating a first average grayscale value of the region of interest based on the grayscale value set of the point set; The point set with grayscale values ​​greater than the first average grayscale value is taken as a first set, and the second average grayscale value of the first set is taken as a third brightness; A point set with grayscale values ​​less than the first average grayscale value is taken as a second set, and a third average grayscale value of the second set is taken as a fourth brightness.

7. The detection system according to claim 4, characterized in that: The obtaining of a modulation transfer function according to the first brightness, the second brightness, the third brightness, and the fourth brightness includes: performing a first operation on the first brightness and the second brightness to obtain a first value; performing a second operation on the third brightness and the fourth brightness to obtain a second value; A third operation is performed on the first value and the second value to obtain a modulation transfer function.

8. The detection system according to claim 1, characterized in that The clarity index includes a modulation transfer function, and determining the imaging quality of the lens to be tested based on the clarity includes: determining whether the modulation transfer function is within a preset range; If the modulation transfer function is within a preset range, determining the quality level of the lens to be tested according to the modulation transfer function and a preset comparison relationship; If the modulation transfer function is not within a preset range, it is determined that the lens to be tested is unqualified.

9. The detection system according to claim 8, characterized in that: The display unit is used for: Different colors are used to display the test results of lenses with different quality levels.

10. A detection method for a lens imaging quality detection system, characterized in that: include: Install the lens to be tested at a preset position of the image acquisition unit; Focusing is performed according to a first preset speed, if the display unit displays clarity; Focusing is performed according to a second preset speed, and the display unit displays the imaging quality.

Images