Detection method and related device

Abstract

The embodiment of the invention provides a detection method and a detection device, which are used for improving the defect detection success rate. The method provided by the embodiment of the invention comprises the following steps: acquiring a height difference of each to-be-detected point of a to-be-detected object along a detection direction; the height difference delta h of the first to-be-detected point and the second to-be-detected point executing adjacent detection in the detection direction of the control device is obtained; obtaining a time difference delta t between adjacent images shot by the imaging device in the imaging process of each to-be-detected point of the to-be-detected object of the control device; according to the control device delta h and the control device delta t, controlling the to-be-detected object of the control device to move along the detection direction of the control device, so that when the first to-be-detected point of the control device is imaged in the field depth range of the imaging device, the second to-be-detected point of the control device is also imaged in the field depth range of the imaging device of the control device; and according to the image of each to-be-detected point of the control device, detecting defects in the to-be-detected object of the control device.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor detection technology, and in particular to a detection method and related devices. Background Art

[0002] The semiconductor industry's pursuit of continuous improvement in manufacturing and testing accuracy has led to higher magnifications for testing lenses, resulting in a smaller range of clear imaging in the height direction. At the same time, because there are more process layers on the wafer surface, the height range for manufacturing and testing needs to cover the bottom layer to the top layer. However, when testing the wafer surface, the existing technology cannot achieve clear imaging and detection of wafers with fluctuating surface heights. Summary of the invention

[0003] The embodiments of the present invention provide a detection method and a detection device, which are used to control the object to be detected to move along the detection direction during the detection process when the surface of the object to be detected presents a height difference along the detection direction, so that each point to be detected on the surface of the object to be detected can be clearly imaged, thereby improving the success rate of defect detection.

[0004] The first aspect of the embodiment of the present application provides a detection method, comprising:

[0005] Acquire the height difference of each to-be-detected point of the to-be-detected object along the detection direction, wherein the height difference includes a first height difference caused by the surface graphic features of the to-be-detected object and / or a second height difference caused by the inherent inclination of the supporting mechanism of the to-be-detected object;

[0006] Acquire a height difference Δh between a first to-be-detected point and a second to-be-detected point in the detection direction for performing adjacent detection;

[0007] Acquire the time difference Δt between adjacent images taken by the imaging device during the imaging process of each to-be-detected point of the to-be-detected object;

[0008] According to the Δh and the Δt, controlling the movement of the object to be detected along the detection direction, so that when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected is also imaged within the depth of field of the imaging device;

[0009] Defects in the object to be inspected are inspected based on the images of the various points to be inspected.

[0010] A second aspect of the embodiment of the present application provides a detection system, including:

[0011] An imaging device, used for imaging each to-be-detected point of the to-be-detected object, the imaging device having a preset depth of field range;

[0012] A carrying mechanism, used for carrying an object to be detected, wherein each to-be-detected point of the object to be detected has a height difference along a detection direction, wherein the height difference includes a first height difference caused by a surface graphic feature of the object to be detected, and / or a second height difference caused by an inherent tilt of the carrying mechanism of the object to be detected;

[0013] A control device, used for acquiring a height difference Δh between a first to-be-detected point and a second to-be-detected point in the detection direction for performing adjacent detection;

[0014] Acquire the time difference Δt between adjacent images during the imaging process of each to-be-detected point of the to-be-detected object;

[0015] According to the Δh and the Δt, controlling the movement of the object to be detected along the detection direction, so that when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected is also imaged within the depth of field of the imaging device;

[0016] The detection device is used to detect defects in the object to be detected based on the images of the various points to be detected.

[0017] A third aspect of an embodiment of the present application provides a computer device, including a processor, which is used to implement the detection method described in the first aspect of the embodiment of the present application when executing a computer program stored in a memory.

[0018] A fourth aspect of an embodiment of the present application provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it is used to implement the detection method described in the first aspect of the embodiment of the present application.

[0019] It can be seen from the above technical solutions that the embodiments of the present invention have the following advantages:

[0020] The embodiment of the present application can pre-acquire the height difference of each inspection point in the object to be inspected along the inspection direction, and obtain the height difference Δh between the first inspection point and the second inspection point in the inspection direction for performing adjacent inspections, as well as the time difference Δt between adjacent images taken by the imaging device during the imaging process of each inspection point of the object to be inspected; further, based on Δh and Δt, the movement of the object to be inspected along the inspection direction is controlled, so that when the first inspection point is imaged within the depth of field of the imaging device, the second inspection point is also imaged within the depth of field of the imaging device, so that when the inspection points in the object to be inspected are located in different planes, each inspection point can be imaged within the depth of field of the imaging device, thereby improving the success rate of defect detection in the object to be inspected. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of an embodiment of the detection method in the embodiment of the present application;

[0022] Figure 2 It is a detailed step of step 101 in the embodiment of the present application;

[0023] Figure 3 It is another detailed step of step 101 in the embodiment of the present application;

[0024] Figure 4 A schematic diagram of a square wave signal in an embodiment of the present application;

[0025] Figure 5 This is a schematic diagram of an embodiment of testing a control signal and a motion mechanism in an embodiment of the present application;

[0026] Figure 6 This is another schematic diagram of an embodiment of testing a control signal and a motion mechanism in an embodiment of the present application;

[0027] Figure 7 This is a schematic diagram of an embodiment of a detection system in an embodiment of the present application;

[0028] Figure 8 It is a schematic diagram of a detection scene in the prior art. DETAILED DESCRIPTION

[0029] The embodiments of the present invention provide a detection method and a detection device, which are used to control the object to be detected to move along the detection direction during the detection process when the surface of the object to be detected presents a height difference along the detection direction, so that each point to be detected on the surface of the object to be detected can be clearly imaged, thereby improving the success rate of defect detection.

[0030] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0031] The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0032] The semiconductor industry has been continuously improving the detection accuracy of the objects to be detected, making the detection lens magnification higher. The higher the detection magnification of the lens, the smaller the clear imaging range of the object to be detected in the height direction. Figure 8 In the detection scenario shown, the object to be detected is generally placed on a supporting mechanism, and then an optical imaging device is used to photograph the imaging area on the object to be detected. However, because the clear imaging range of the object to be detected in the height direction is small, when there is a height difference in the height direction of the points to be detected of the object to be detected, each point to be detected cannot be imaged within the depth of field of the optical imaging device.

[0033] In view of the above problems, the present application proposes a detection method for clearly imaging the points to be detected at different heights on the object to be detected. For ease of understanding, the detection method in the embodiment of the present application is described below. Figure 1 , an embodiment of the detection method in the embodiments of the present application comprises:

[0034] 101. Obtaining height differences of each to-be-detected point of the to-be-detected object along a detection direction, wherein the height difference includes a first height difference caused by a surface graphic feature of the to-be-detected object and / or a second height difference caused by an inherent tilt of a supporting mechanism of the to-be-detected object;

[0035] As the semiconductor industry continues to improve its manufacturing and testing accuracy, the detection objective is required to simultaneously clearly image different planes in the height direction of the object to be detected. However, the higher the magnification of the detection objective, the smaller the range of clear imaging in the height direction, making it impossible for the detection objective to clearly image each plane in the height direction.

[0036] It should be noted that the height direction of the object to be detected here is the same as the detection direction in the embodiment of the present application, and the detection direction in the embodiment of the present application is the optical axis direction when the imaging device images the object to be detected.

[0037] Specifically, the object to be detected in the embodiment of the present application has multiple uneven planes to be detected in the detection direction, or there is a height difference between the planes where each point to be detected in the object to be detected is located along the detection direction. In order to achieve clear imaging of the points to be detected located on multiple planes at different heights, it is necessary to obtain the height difference of each point to be detected in the object to be detected along the height direction in the embodiment of the present application, wherein the height difference here includes a first height difference caused by the surface graphic features of the object to be detected, and / or a second height difference caused by the inherent inclination of the supporting mechanism of the object to be detected.

[0038] Further, the first height difference in the embodiment of the present application can be understood as the surface of the object to be detected is etched with different concave and convex graphic features, so that the different concave and convex graphics form a height difference in the height direction, and the second height difference in the embodiment of the present application can be understood as when imaging the object to be detected, one is generally to place the object to be detected on a carrying mechanism (such as a carrying platform), and under normal circumstances, the surface of the carrying structure is required to be arranged in parallel. However, in actual situations, due to the inclination of the carrying structure and other reasons, it will cause a certain height difference to occur at each point to be detected on the object to be detected placed on the carrying structure. In actual detection scenarios, scenarios with height differences include:

[0039] 1. The first height difference caused by the presence of graphic features on the surface of the object to be detected;

[0040] 2. The surface of the object to be detected has no graphic features, but the supporting mechanism of the object to be detected has a second height difference caused by tilt;

[0041] 3. There is a first height difference on the surface of the object to be detected due to the graphic features, and there is also a second height difference on the bearing structure of the object to be detected due to the tilt.

[0042] 102. Obtain a height difference Δh between a first to-be-detected point and a second to-be-detected point in the detection direction for performing adjacent detection;

[0043] In order to ensure that each point to be detected on different planes in the height direction of the object to be detected can be located within the depth of field of the imaging device, that is, to achieve clear imaging of each point to be detected on the object to be detected, the idea of ​​the solution of the embodiment of the present application is: control the imaging device to move each point to be detected in the detection direction when imaging each point to be detected, so that each point to be detected is located within the depth of field of the imaging device.

[0044] When detecting the object to be detected, if the image features in the object to be detected are fixed, then each point to be detected is generally fixed. When detecting each point to be detected, a certain detection path is generally set, such as an S-shaped detection path, or an X-shaped detection path, or a random detection path, etc. In order to achieve clear imaging of each point to be detected, it is generally necessary to obtain the height difference Δh in the detection direction between the first point to be detected and the second point to be detected performing adjacent detections, so that when the first point to be detected is within the depth of field of the imaging device, the corresponding movement Δh of the object to be detected in the height direction (upward or downward) can be controlled, so that the second point to be detected can also be imaged within the depth of field of the imaging device.

[0045] 103. Acquire a time difference Δt between adjacent images taken by an imaging device during the imaging process of each to-be-detected point of the to-be-detected object;

[0046] When imaging adjacent images using an imaging device, each imaging device is generally set with an adjacent time difference Δt. For example, when the imaging device is a CCD, the adjacent time difference may be 0.1 ms. When the imaging device is fixed, the time difference Δt between adjacent images is also fixed.

[0047] 104. Control the movement of the object to be detected along the detection direction according to the Δh and the Δt, so that when the first point to be detected is imaged within the depth of field of an imaging device, the second point to be detected is also imaged within the depth of field of the imaging device;

[0048] In order to ensure that each point to be detected can be imaged within the depth of field of the imaging device, the embodiment of the present application needs to control the movement distance of the detection object in the detection direction according to Δh and Δt between adjacent points to be detected, so that when the adjacent first point to be detected is imaged within the depth of field of the imaging, the second point to be detected is also imaged within the depth of field of the imaging device.

[0049] For easier understanding, the following example is given:

[0050] Assuming that point 1 to be detected, point 2 to be detected, point 3 to be detected, point 4 to be detected, and point 5 to be detected are set on the object to be detected, when detecting the object to be detected, it is necessary to obtain the first point to be detected and the second point to be detected for performing adjacent detection, wherein the first point to be detected and the second point to be detected here mainly depend on the detection path or detection strategy preset in advance. When sequential detection is performed, the first detection point and the second point to be detected can be any two adjacent points to be detected, and when detection is performed with other paths, the first point to be detected and the second point to be detected can be point 1 to be detected and point 5 to be detected, or point 1 to be detected and point 3 to be detected, etc., that is, the points to be detected for performing adjacent detection mainly depend on the detection path or detection strategy preset in advance.

[0051] After acquiring the first point to be detected and the second point to be detected for performing adjacent detection, when the first point to be detected is located within the depth of field of the imaging, the object to be detected can be controlled to move Δh in the detection direction within the time Δt, so that the second point to be detected is also imaged within the depth of field of the imaging device.

[0052] It is easy to understand that when detecting the first point to be detected in the object to be detected, the imaging device is generally adjusted so that the first point to be detected is imaged within the depth of field of the imaging device. When the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected that performs adjacent detection with the first point to be detected is obtained, as well as the height difference Δh between the second point to be detected and the first point to be detected in the detection direction. Based on Δh and Δt, the object to be detected can be controlled to move Δh in the height direction, so that the second point to be detected is also imaged within the depth of field of the imaging device, and so on. Therefore, each point to be detected in the object to be detected can be imaged within the depth of field of the imaging device.

[0053] 105. Detect defects in the object to be detected based on the images of the points to be detected.

[0054] After obtaining the images of each point to be detected in the object to be detected, the defects in the object to be detected can be detected based on the images of each point to be detected.

[0055] Among them, the objects to be detected in the embodiments of the present application include but are not limited to wafers, glass masks or glass cover plates, and the types of the objects to be detected are not specifically limited here.

[0056] The embodiment of the present application can pre-acquire the height difference of each inspection point in the object to be inspected along the inspection direction, and obtain the height difference Δh between the first inspection point and the second inspection point in the inspection direction for performing adjacent inspections, as well as the time difference Δt between adjacent images taken by the imaging device during the imaging process of each inspection point of the object to be inspected; further, based on Δh and Δt, the movement of the object to be inspected along the inspection direction is controlled, so that when the first inspection point is imaged within the depth of field of the imaging device, the second inspection point is also imaged within the depth of field of the imaging device, so that when the inspection points in the object to be inspected are located in different planes, each inspection point can be imaged within the depth of field of the imaging device, thereby improving the success rate of defect detection in the object to be inspected.

[0057] based on Figure 1 In the embodiment described above, when the height difference in step 101 includes the first height difference and the second height difference, a method for obtaining the height difference of each to-be-detected point of the to-be-detected object along the detection direction is described in detail below:

[0058] 1. If the height difference includes a second height difference caused by the inherent inclination of the supporting mechanism of the object to be detected;

[0059] See also Figure 2 , Figure 2 A refinement of step 101:

[0060] 201. When a reference detection object is placed on the inherently tilted carrying mechanism, the reference height difference of each to-be-detected point on the reference detection object along the detection direction is measured respectively, wherein the surface of the reference detection object has no image features, and the first position coordinate of the reference detection object relative to the carrying mechanism is the same as the second position coordinate of the to-be-detected object relative to the carrying mechanism;

[0061] In actual situations, when the supporting mechanism cannot be set horizontally due to structural reasons, if there is an inherent tilt inside the supporting mechanism, the inherent tilt is a fixed value. The height difference of each to-be-detected point in the to-be-detected object along the detection direction caused by the inherent tilt can be obtained in the following way:

[0062] A reference detection object can be placed on a carrying mechanism with an inherent tilt, wherein, except for the absence of image features on the surface, the reference detection object has completely the same structural features and appearance features as the object to be detected, and the placement position of the reference detection object on the carrying mechanism is completely the same as the placement position of the object to be detected on the carrying mechanism, that is, the first position coordinates of the reference detection object relative to the carrying mechanism are completely the same as the second position coordinates of the object to be detected relative to the carrying mechanism.

[0063] In actual detection scenarios, a coordinate system is generally set on the surface of the supporting mechanism where the detection object is placed. Therefore, the first position coordinates of the reference detection object in the coordinate system can be obtained through the coordinate system, or the second position coordinates of the object to be detected in the coordinate system can be obtained. By setting the first position coordinates and the second position coordinates, the first position coordinates of the reference detection object relative to the supporting mechanism are exactly the same as the second position coordinates of the object to be detected relative to the supporting mechanism.

[0064] When the reference detection object is placed on the supporting mechanism, the reference height difference of each point to be detected on the reference detection object along the detection direction can be measured respectively. When measuring the reference height difference, a high-precision height measuring sensor arranged at the position of the imaging device can be used to measure the height value of each point to be detected respectively, and the height value of each point to be detected can be further used to calculate the height difference of each point to be detected in the detection direction.

[0065] It should be noted here that, generally when calculating the height difference, the height difference between the first point to be detected and the second point to be detected for performing adjacent detection is generally calculated, and the first point to be detected and the second point to be detected for performing adjacent detection depend on the path for performing the detection or the strategy for performing the detection. When the path for performing the detection or the strategy for performing the detection is fixed, the first point to be detected and the second point to be detected for performing adjacent detection are also fixed, and accordingly, the height difference of each point to be detected along the detection direction is also fixed.

[0066] 202. Determine the reference height difference as the height difference between each to-be-detected point of the to-be-detected object along the detection direction.

[0067] After obtaining the reference height difference of each to-be-detected point of the reference detection object along the detection direction in step 201, the reference height difference is further regarded as the height difference of each to-be-detected point of the to-be-detected object along the detection direction, thereby improving the convenience of obtaining the second height difference.

[0068] 2. If the height difference includes a first height difference caused by a surface graphic feature of the object to be detected;

[0069] See also Figure 3 , Figure 3 Another refinement of step 101:

[0070] 301. When the object to be detected is placed on a horizontally arranged supporting mechanism, first height differences of each point to be detected on the object to be detected along a detection direction are measured respectively, wherein the surface of the object to be detected has graphic features;

[0071] When the height difference of each point to be detected in the object to be detected along the detection direction is caused by the graphic characteristics on the surface of the object to be detected, the object to be detected can be placed on a horizontally arranged supporting mechanism, and then a high-precision height measuring sensor can be used to measure the first height difference of each point to be detected along the detection direction.

[0072] Specifically, the first height difference of each inspected point along the detection direction is also the height difference between each inspected point for adjacent detections, and the first inspected point and the second inspected point for adjacent detections also depend on the detection path or detection strategy.

[0073] 302. Determine the first height difference as a height difference between each to-be-detected point of the to-be-detected object along the detection direction.

[0074] After the first height difference is obtained, the first height difference is determined as the height difference of each to-be-detected point of the to-be-detected object along the detection direction.

[0075] In the above embodiment, the method of obtaining the first height difference and the second height difference is described in detail, and the first height difference and the second height difference are measured by a high-precision height measuring sensor, which improves the convenience of obtaining the first height difference and the second height difference.

[0076] Further, based on Figure 1 In the above embodiment, when the first to-be-detected point and the second to-be-detected point are not located in the same field of view of the imaging device, the above detection method further includes:

[0077] A distance d1 between a first point to be detected and a second point to be detected in the same plane is obtained, and according to d1 and Δt, the field of view of the imaging device is controlled to move from the first point to be detected to the second point to be detected.

[0078] It is easy to understand that when the first point to be detected and the second point to be detected are not located in the same field of view of the imaging device, in order to clearly image the second point to be detected, the object to be detected not only needs to be controlled to move Δh in the detection direction within the Δt time, but also needs to control the object to be detected to move in the horizontal direction perpendicular to the detection direction (that is, the field of view plane direction of the imaging device) within the Δt time, so that the field of view of the imaging device is changed from the first point to be detected to the second point to be detected. Therefore, the embodiment of the present application also needs to obtain the distance d1 between the first point to be detected and the second point to be detected in the same plane, and control the object to be detected to move a distance d1 along the direction of the line connecting the first point to be detected and the second point to be detected in the same plane, so that the field of view of the imaging device moves from the first point to be detected to the second point to be detected.

[0079] In actual scenarios, the supporting mechanism and the object to be detected are generally rotated by a motion mechanism, and during the rotation process, the second point to be detected is moved in the detection direction, and the second point to be detected is moved in the plane direction perpendicular to the detection direction. Therefore, in the actual rotational motion scenario, the motion mechanism can drive the supporting mechanism to move Δh along the detection direction within the Δt time, and at the same time, the object to be detected is controlled to move a distance d1 in the direction of the line connecting the first point to be detected and the second point to be detected in the same plane within the Δt time, so that the field of view of the imaging device moves from the first point to be detected to the second point to be detected.

[0080] As another optional embodiment, when the field of view of the imaging device is switched from the first point to be detected to the second point to be detected, the imaging device can also be controlled to move a distance d1 in the same plane direction along the first point to be detected and the second point to be detected, and the imaging device can be controlled to move another Δh along the detection direction (Δh here can be a corresponding upward or downward movement of Δh in the detection direction), so that the field of view of the imaging device moves from the first point to be detected to the second point to be detected, and the second detection point is also imaged within the depth of field of the imaging device.

[0081] based on Figure 1 In the above-mentioned embodiment, when controlling the object to be detected to move along the detection direction, as an optional embodiment, a control signal may be used to control the motion mechanism to drive the bearing mechanism and the object to be detected to move along the detection direction. Specifically, the control signal here may be a sinusoidal control signal or a square wave control signal (for ease of understanding, Figure 4 A schematic diagram of a square wave signal is given), thereby realizing the automatic movement of the object to be detected based on the control signal and the motion system, that is, realizing the automatic detection of each point to be detected in the object to be detected.

[0082] Furthermore, in order to realize automatic control of the control signal over the object to be detected, it is generally necessary to test the control signal and the motion mechanism before using the control signal to control the motion mechanism to drive the carrying mechanism and the object to be detected to move along the detection direction, so as to test whether the control signal and the motion mechanism can drive the carrying mechanism and the object to be detected to move, so that each point to be detected of the object to be detected is imaged within the depth of field of the imaging device.

[0083] The following describes the process of testing the control signal and the motion mechanism. Figure 5 , an embodiment of testing the control signal and the motion mechanism in the embodiment of the present application includes:

[0084] 501. Obtain any two third points to be detected and fourth points to be detected for performing adjacent detection;

[0085] The embodiment of the present application mainly tests whether the control signal can control the motion mechanism to move, so that among any two points to be detected in adjacent tests, when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected can also be imaged within the depth of field of the imaging device under the control of the control signal and the motion mechanism.

[0086] Therefore, in the embodiment of the present application, any two third points to be detected and fourth points to be detected for performing adjacent detection are obtained, and step 502 is performed on the third points to be detected and the fourth points to be detected.

[0087] 502. If the third to-be-detected point and the fourth to-be-detected point are not located in the same field of view, the third to-be-detected point is imaged within the depth of field of the imaging device, and after the imaging of the third to-be-detected point is completed, the motion mechanism is controlled by the control signal to move along the line direction of the third to-be-detected point and the fourth to-be-detected point in the same plane for Δt, and then it is determined whether the fourth detection point is located in the field of view of the imaging device. If so, step 503 is executed; if not, step 505 is executed;

[0088] Specifically, when judging whether the fourth point to be detected is located within the field of view of the imaging device, it can be judged whether the image taken by the imaging device contains the fourth point to be detected. If so, it is determined that the fourth point to be detected is located within the field of view of the imaging device; otherwise, it is determined that the fourth point to be detected is not located within the field of view of the imaging device.

[0089] 503. When the third point to be detected is imaged within the depth of field of the imaging device and the imaging of the third point to be detected is completed, the motion mechanism is controlled to move along the detection direction by Δt using the control signal, and then it is determined whether the fourth point to be detected is imaged within the depth of field of the imaging device. If so, step 504 is executed; if not, step 505 is executed.

[0090] After acquiring any two third and fourth points to be detected for performing adjacent detection, if the third point to be detected is imaged within the depth of field of the imaging device, and after the imaging of the third point to be detected is completed, the motion mechanism is controlled to move Δt along the detection direction using a control signal, and then it is determined whether the fourth point to be detected is imaged within the depth of field of the imaging device. If the fourth point to be detected is imaged within the depth of field of the imaging device, the fourth point to be detected can be clearly imaged by the imaging device; otherwise, the fourth point to be detected cannot be clearly imaged.

[0091] 504. Determine whether the control signal and the motion mechanism are qualified, and store the control signal;

[0092] If the fourth point to be detected is imaged within the depth of field of the imaging device, it is determined that the control signal and the motion mechanism are qualified, and the control signal is stored.

[0093] 505. Determine that the control signal and / or the motion mechanism is unqualified.

[0094] If the fourth to-be-detected point is not imaged within the depth of field of the imaging device, it is determined that the control signal and / or the motion mechanism is unqualified.

[0095] It should be noted that when the third to-be-detected point and the fourth to-be-detected point are located in the same field of view, step 502 is skipped and steps 503 to 505 are directly executed.

[0096] The test process of the control signal and the motion mechanism is described in detail in the embodiment of the present application, and the test process of the control signal and the motion mechanism is described by arbitrarily selecting a third point to be detected and a fourth point to be detected for performing adjacent tests in the embodiment of the present application, thereby improving the convenience of the test process of the control signal and the motion mechanism.

[0097] In addition, the embodiment of the present application can also test the control signal and the motion mechanism by another method, please refer to Figure 6 Another embodiment of testing the control signal and the motion mechanism in the embodiment of the present application includes:

[0098] 601. Obtain any two third points to be detected and fourth points to be detected for performing adjacent detection;

[0099] The embodiment of the present application mainly tests whether the control signal can control the motion mechanism to move, so that among any two points to be detected in adjacent tests, when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected can also be imaged within the depth of field of the imaging device under the control of the control signal and the motion mechanism.

[0100] Therefore, in the embodiment of the present application, any two third points to be detected and fourth points to be detected for performing adjacent detection are obtained, and step 602 is performed on the third points to be detected and the fourth points to be detected.

[0101] 602. If the third to-be-detected point and the fourth to-be-detected point are not located in the same field of view, the third to-be-detected point is imaged within the depth of field of the imaging device, and after the imaging of the third to-be-detected point is completed, the motion mechanism is controlled by the control signal to move along the line direction of the third to-be-detected point and the fourth to-be-detected point in the same plane for Δt, and then it is determined whether the fourth detection point is located in the field of view of the imaging device. If so, step 603 is executed; if not, step 608 is executed;

[0102] 603. Acquire a plurality of height differences between adjacent detection points among the detection points;

[0103] For ease of understanding, the following distance description:

[0104] Assume that the object to be detected has 5 points to be detected, namely point 1 to be detected, point 2 to be detected, point 3 to be detected, point 4 to be detected and point 5 to be detected, and if the strategy for executing detection on the 5 points to be detected is sequential detection.

[0105] Then, in the embodiment of the present application, the height difference between the points to be detected 1 and 2, the height difference between 2 and 3, the height difference between 3 and 4, and the height difference between 4 and 5 are respectively obtained, thereby obtaining multiple height differences.

[0106] 604. Obtain a maximum height difference among the multiple height differences;

[0107] After obtaining multiple height differences, the maximum height difference is taken from the multiple height differences.

[0108] 605. Obtain the maximum target height difference corresponding to adjacent moments in the control signal;

[0109] Furthermore, the maximum target height difference corresponding to adjacent moments is obtained in the control signal, wherein the maximum target height difference is the maximum height value of the motion mechanism controlled by the control signal to move along the detection direction at adjacent moments in the control signal.

[0110] Corresponding to Figure 4 In the square wave signal, the maximum value among h1, h2, h3 and h4 is read.

[0111] 606. Determine whether the maximum target height difference is greater than or equal to the maximum height difference. If so, execute step 607; if not, execute step 608;

[0112] If the maximum target height value is greater than or equal to the maximum height difference, step 607 is executed; if the maximum target height difference is less than the maximum height difference, step 608 is executed.

[0113] 607. Determine that the control signal and the motion mechanism are qualified, and store the control signal;

[0114] If the maximum target height value is greater than or equal to the maximum height value, it means that if the previous point to be detected among the two adjacent points to be detected is located within the depth of field of the imaging device, the control signal can successfully control the motion mechanism to drive the supporting mechanism and the point to be detected to move in the detection direction, so that the latter point to be detected among the two adjacent points to be detected is also located within the depth of field of the imaging device, which means that the control signal and the motion mechanism are qualified, and the control signal is stored.

[0115] 608. Determine that the control signal and / or the motion mechanism is unqualified.

[0116] If the maximum target height value is less than the maximum height value, it means that when the previous point to be detected among the two adjacent points to be detected is located within the depth of field of the imaging device, the control signal cannot control the motion mechanism to drive the supporting mechanism and the point to be detected to move in the detection direction, thereby causing the latter point to be detected among the two adjacent points to be detected to also be located within the depth of field of the imaging device, which means that the control signal and / or the motion mechanism is unqualified.

[0117] It should be noted that when the third point to be detected and the fourth point to be detected are not located in the same field of view, steps 601 to 608 need to be executed, and when the third point to be detected and the fourth point to be detected are located in the same field of view, steps 601 and 602 are skipped and steps 603 to 608 are executed directly.

[0118] The test process of testing the control signal and the motion mechanism is described in detail in the embodiment of the present application. When testing the control signal in the detection direction, it is only necessary to theoretically obtain the maximum height value among multiple height values ​​and the maximum target height value in the control signal to complete the test of the control signal in the detection direction, thereby further improving the convenience of the test process of the control signal and / or the motion mechanism.

[0119] The above describes the detection method in the embodiment of the present application in detail. The following describes the detection system in the embodiment of the present application. Figure 7 , an embodiment of the detection system in the embodiment of the present application includes:

[0120] An imaging device 701 is used to image each to-be-detected point of the to-be-detected object, and the imaging device has a preset depth of field range;

[0121] A carrying mechanism 702, used for carrying an object to be detected, wherein each to-be-detected point of the object to be detected has a height difference along the detection direction, wherein the height difference includes a first height difference caused by a surface graphic feature of the object to be detected, and / or a second height difference caused by an inherent tilt of the carrying mechanism of the object to be detected;

[0122] The control device 703 is used to obtain a height difference Δh between a first point to be detected and a second point to be detected in the detection direction for performing adjacent detection;

[0123] Acquire the time difference Δt between adjacent images taken by the imaging device during the imaging process of each to-be-detected point of the to-be-detected object;

[0124] According to the Δh and the Δt, controlling the movement of the object to be detected along the detection direction, so that when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected is also imaged within the depth of field of the imaging device;

[0125] The detection device 704 is used to detect defects in the object to be detected based on the images of the various points to be detected.

[0126] Preferably, when the height difference includes a second height difference caused by an inherent tilt of a supporting mechanism of the object to be detected, the control device 703 is specifically configured to:

[0127] When a reference detection object is placed on the inherently tilted carrying mechanism, the reference height differences of each to-be-detected point on the reference detection object along the detection direction are measured respectively, wherein the surface of the reference detection object has no image features, and the first position coordinates of the reference detection object relative to the carrying mechanism are the same as the second position coordinates of the to-be-detected object relative to the carrying mechanism;

[0128] The reference height difference is determined as the height difference of each to-be-detected point of the to-be-detected object along the detection direction.

[0129] Preferably, when the height difference includes a first height difference caused by a surface graphic feature of the object to be detected, the control device 703 is specifically used to:

[0130] When the object to be detected is placed on a horizontally arranged supporting mechanism, first height differences of various points to be detected on the object to be detected along a detection direction are measured respectively, wherein the surface of the object to be detected has graphic features;

[0131] The first height difference is determined as the height difference of each to-be-detected point of the to-be-detected object along the detection direction.

[0132] Preferably, when the first to-be-detected point and the second to-be-detected point are not located in the same field of view of the imaging device, the control device 703 is specifically used to:

[0133] Acquire a distance d1 between the first to-be-detected point and the second to-be-detected point in the same plane;

[0134] According to the d1 and the Δt, the field of view of the imaging device is controlled to move from the first point to be detected to the second point to be detected.

[0135] Preferably, the control device 703 is specifically used for:

[0136] The motion mechanism is controlled by a control signal to drive the bearing mechanism and the object to be detected to move along the detection direction, wherein the control signal includes a sinusoidal control signal or a square wave control signal.

[0137] Preferably, the detection system further comprises:

[0138] The testing device 705 is used to test the control signal and the motion mechanism before using the control signal to control the motion mechanism to drive the supporting mechanism and the object to be detected to move along the detection direction, so as to test whether the control signal and the motion mechanism can drive the supporting mechanism and the object to be detected to move, so that each point to be detected of the object to be detected is imaged within the depth of field of the imaging device.

[0139] Preferably, the testing device 705 is specifically used for:

[0140] Obtain any two third points to be detected and fourth points to be detected for performing adjacent detection;

[0141] When the third point to be detected is imaged within the depth of field of the imaging device and the imaging of the third point to be detected is completed, after the motion mechanism is controlled to move along the detection direction by Δt using the control signal, it is determined whether the fourth point to be detected is imaged within the depth of field of the imaging device;

[0142] If yes, it is determined that the control signal and the motion mechanism are qualified, and the control signal is stored;

[0143] If not, it is determined that the control signal and / or the motion mechanism is unqualified.

[0144] Preferably, the testing device 705 is specifically used for:

[0145] Acquire a plurality of height differences between adjacent detection points among the detection points;

[0146] Obtaining a maximum height difference among the multiple height differences;

[0147] Obtaining the maximum target height difference corresponding to adjacent moments in the control signal;

[0148] Determining whether the maximum target height difference is greater than or equal to the maximum height difference;

[0149] If yes, it is determined that the control signal and the motion mechanism are qualified, and the control signal is stored;

[0150] If not, it is determined that the control signal and / or the motion mechanism is unqualified.

[0151] Preferably, when the third to-be-detected point and the fourth to-be-detected point are not located in the same field of view of the imaging device, the testing device 705 is further used for:

[0152] When the third point to be detected is imaged within the depth of field of the imaging device and the imaging of the third point to be detected is completed, the motion mechanism is controlled by the control signal to move Δt along the line connecting the third point to be detected and the fourth point to be detected in the same plane, and then it is determined whether the fourth detection point is within the field of view of the imaging device;

[0153] If yes, it is determined that the control signal and the motion mechanism are qualified, and the control signal is stored;

[0154] If not, it is determined that the control signal and / or the motion mechanism is unqualified.

[0155] In an embodiment of the present application, the control device 703 can pre-acquire the height difference of each inspection point in the object to be inspected along the inspection direction, and obtain the height difference Δh in the inspection direction between the first inspection point and the second inspection point performing adjacent inspections, as well as the time difference Δt between adjacent images of each inspection point of the object to be inspected during the imaging process; further, based on Δh and Δt, the movement of the object to be inspected along the inspection direction is controlled, so that when the first inspection point is imaged within the depth of field of the imaging device, the second inspection point is also imaged within the depth of field of the imaging device, so that when the inspection points in the object to be inspected are located in different planes, each inspection point can be imaged within the depth of field of the imaging device, thereby improving the success rate of defect detection in the object to be inspected.

[0156] The detection system in the embodiment of the present invention is described above from the perspective of modular functional entities. The computer device in the embodiment of the present invention is described below from the perspective of hardware processing:

[0157] The computer device is used to implement the functions of the detection system. In an embodiment of the present invention, an embodiment of the computer device includes:

[0158] Processor and memory;

[0159] The memory is used to store computer programs, and when the processor is used to execute the computer programs stored in the memory, it can achieve Figures 1 to 6 The various steps of the detection method.

[0160] It is understandable that when the processor in the computer device described above executes the computer program, it can also implement the functions of the various units in the above-mentioned corresponding device embodiments, which will not be repeated here. Exemplarily, the computer program can be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units can be a series of computer program instruction segments that can perform specific functions, and the instruction segments are used to describe the execution process of the computer program in the detection system. For example, the computer program can be divided into the various units in the above-mentioned detection system, and each unit can implement the specific functions described in the above-mentioned corresponding detection system.

[0161] The computer device may be a computing device such as a desktop computer, a notebook, a PDA, and a cloud server. The computer device may include, but is not limited to, a processor and a memory. Those skilled in the art will appreciate that a processor and a memory are merely examples of computer devices and do not constitute a limitation of the computer device. The computer device may include more or fewer components, or a combination of certain components, or different components. For example, the computer device may also include input and output devices, network access devices, buses, and the like.

[0162] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the computer device, and uses various interfaces and lines to connect various parts of the entire computer device.

[0163] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the computer device by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required for a function, etc.; the data storage area can store data created according to the use of the terminal, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0164] The present invention also provides a computer-readable storage medium, which is used to implement the functions of the detection system, and stores a computer program. When the computer program is executed by a processor, the processor can be used to execute Figures 1 to 6 The various steps of the detection method.

[0165] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0166] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0167] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0168] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A detection method, It is characterized in that The method comprises: Acquire the height difference of each to-be-detected point of the to-be-detected object along the detection direction, wherein the height difference includes a first height difference caused by the surface graphic features of the to-be-detected object and / or a second height difference caused by the inherent inclination of the supporting mechanism of the to-be-detected object; Acquire a height difference Δh between a first to-be-detected point and a second to-be-detected point in the detection direction for performing adjacent detection; Acquire the time difference Δt between adjacent images taken by the imaging device during the imaging process of each to-be-detected point of the to-be-detected object; According to the Δh and the Δt, controlling the movement of the object to be detected along the detection direction, so that when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected is also imaged within the depth of field of the imaging device; Defects in the object to be inspected are inspected based on the images of the various points to be inspected.

2. The imaging method according to claim 1, It is characterized in that When the height difference includes a second height difference caused by the inherent inclination of the supporting mechanism of the object to be detected, the step of obtaining the height difference of each to-be-detected point of the object to be detected along the detection direction includes: When a reference detection object is placed on the inherently tilted carrying mechanism, the reference height differences of each to-be-detected point on the reference detection object along the detection direction are measured respectively, wherein the surface of the reference detection object has no image features, and the first position coordinates of the reference detection object relative to the carrying mechanism are the same as the second position coordinates of the to-be-detected object relative to the carrying mechanism; The reference height difference is determined as the height difference of each to-be-detected point of the to-be-detected object along the detection direction.

3. The imaging method according to claim 1, It is characterized in that When the height difference includes a first height difference caused by a surface graphic feature of the object to be detected, the step of obtaining the height difference of each to-be-detected point of the object to be detected along the detection direction includes: When the object to be detected is placed on a horizontally arranged supporting mechanism, first height differences of various points to be detected on the object to be detected along a detection direction are measured respectively, wherein the surface of the object to be detected has graphic features; The first height difference is determined as the height difference of each to-be-detected point of the to-be-detected object along the detection direction.

4. The method according to claim 1, It is characterized in that When the first to-be-detected point and the second to-be-detected point are not located in the same field of view of the imaging device, the method further includes: Acquire a distance d1 between the first to-be-detected point and the second to-be-detected point in the same plane; According to the d1 and the Δt, the field of view of the imaging device is controlled to move from the first point to be detected to the second point to be detected.

5. The method according to claim 1, It is characterized in that The step of controlling the movement of the object to be detected along the detection direction according to the Δh and the Δt comprises: The motion mechanism is controlled by a control signal to drive the bearing mechanism and the object to be detected to move along the detection direction, wherein the control signal includes a sinusoidal control signal or a square wave control signal.

6. The method according to claim 5, It is characterized in that Before using the control signal to control the motion mechanism to drive the bearing mechanism and the object to be detected to move along the detection direction, the method further includes: The control signal and the motion mechanism are tested to test whether the control signal and the motion mechanism can drive the supporting mechanism and the object to be detected to move, so that each point to be detected of the object to be detected is imaged within the depth of field of the imaging device.

7. The method according to claim 6, It is characterized in that The testing of the control signal and the motion mechanism includes: Obtain any two third points to be detected and fourth points to be detected for performing adjacent detection; When the third point to be detected is imaged within the depth of field of the imaging device and the imaging of the third point to be detected is completed, after the motion mechanism is controlled to move along the detection direction by Δt using the control signal, it is determined whether the fourth point to be detected is imaged within the depth of field of the imaging device; If yes, determining that the control signal and the motion mechanism are qualified, and storing the control signal; If not, it is determined that the control signal and / or the motion mechanism is unqualified.

8. The method according to claim 6, It is characterized in that The testing of the control signal and the motion mechanism includes: Acquire a plurality of height differences between adjacent detection points among the detection points; Obtaining a maximum height difference among the multiple height differences; Obtaining the maximum target height difference corresponding to adjacent moments in the control signal; Determining whether the maximum target height difference is greater than or equal to the maximum height difference; If yes, determining that the control signal and the motion mechanism are qualified, and storing the control signal; If not, it is determined that the control signal and / or the motion mechanism is unqualified.

9. The method according to claim 7 or 8, It is characterized in that When the third to-be-detected point and the fourth to-be-detected point are not located in the same field of view of the imaging device, the method further includes: When the third point to be detected is imaged within the depth of field of the imaging device and the imaging of the third point to be detected is completed, the motion mechanism is controlled by the control signal to move Δt along the line connecting the third point to be detected and the fourth point to be detected in the same plane, and then it is determined whether the fourth detection point is within the field of view of the imaging device; If yes, it is determined that the control signal and the motion mechanism are qualified; If not, it is determined that the control signal and / or the motion mechanism is unqualified.

10. A detection system, It is characterized in that The detection system comprises: An imaging device, used for imaging each to-be-detected point of the to-be-detected object, the imaging device having a preset depth of field range; A carrying mechanism, used for carrying an object to be detected, wherein each to-be-detected point of the object to be detected has a height difference along a detection direction, wherein the height difference includes a first height difference caused by a surface graphic feature of the object to be detected, and / or a second height difference caused by an inherent tilt of the carrying mechanism of the object to be detected; A control device, used for acquiring a height difference Δh between a first to-be-detected point and a second to-be-detected point in the detection direction for performing adjacent detection; Acquire the time difference Δt between adjacent images taken by the imaging device during the imaging process of each to-be-detected point of the to-be-detected object; According to the Δh and the Δt, controlling the movement of the object to be detected along the detection direction, so that when the first point to be detected is imaged within the depth of field of the imaging device, the second point to be detected is also imaged within the depth of field of the imaging device; The detection device is used to detect defects in the object to be detected based on the images of the various points to be detected.

11. A computer device comprising a processor, It is characterized in that When executing the computer program stored in the memory, the processor is used to implement the detection method according to any one of claims 1 to 9.

12. A computer-readable storage medium having a computer program stored thereon, It is characterized in that When the computer program is executed by a processor, it is used to implement the detection method according to any one of claims 1 to 9.

Images