Detection apparatus and detection method

Abstract

A detection apparatus and a detection method. The detection apparatus comprises a first light source (100), a first polarizer (101), a second polarizer (102), a third polarizer (103), a first detector assembly (104), a second detector assembly (105) and a processor, wherein the first light source (100) is used for providing first light to a first surface (12) of an object (11) to be subjected to detection; the first polarizer (101) is used for converting the first light into first polarized light, the first polarized light being transmitted through said object (11) to form first transmitted signal light, the first polarized light being reflected by the first surface (12) to form first return light, the first return light passing through the second polarizer (102) to form first signal light, and the first transmitted signal light passing through the third polarizer (103) to form second signal light; the first detector assembly (104) is used for receiving the first signal light; the second detector assembly (105) is used for receiving the second signal light; and the processor performs detection on said object (11) on the basis of the first signal light and the second signal light. Two types of defect detection are implemented by means of one light source, thus improving the practicability of the detection apparatus.

Description

Detection device and detection method Cross-referencing

[0001] This application claims priority to Chinese Patent Application No. 202510369123.0, filed on March 27, 2025, entitled "Detection Apparatus and Detection Method", which is incorporated herein by reference in its entirety. Technical Field

[0002] This application relates to the field of detection technology, and in particular to a detection device and detection method. Background Technology

[0003] In semiconductor manufacturing, defect detection is necessary at every stage of the process to ensure the quality of semiconductor devices. Semiconductor materials often contain various types of defects, and detection devices typically require multiple detection modes to detect these diverse defects.

[0004] In related technologies, the detection devices often employ a single detection mode, such as using only a single light source to detect a single type of defect. This can lead to missed defects in the test object, reducing the practicality of the detection device. Furthermore, because the detection devices operate on a single mode, operators need to switch devices to detect defects under different light sources, resulting in low efficiency and further reducing their practicality. Therefore, the detection devices in related technologies have limited practicality. Summary of the Invention

[0005] This application provides a detection device that at least improves the practicality of the detection device.

[0006] According to some embodiments of this application, one aspect of this application provides a detection device, comprising: a first light source for providing first light to a first surface of an object to be tested; a first polarizer for converting the first light into first polarized light, wherein the first polarized light is transmitted through the object to be tested to form a first transmitted signal light, and the first polarized light returns through the first surface to form a first returned light; a second polarizer for the first returned light to form a first signal light, wherein the polarization direction of the second polarizer is not perpendicular to the polarization direction of the first polarizer; a third polarizer for the third polarizer to have a polarization direction perpendicular to the polarization direction of the first polarizer, wherein the first transmitted signal light is transmitted through the third polarizer to form a second signal light; a first detection component for receiving the first signal light; a second detection component for receiving the second signal light; and a processor for detecting the object to be tested based on the first signal light and the second signal light.

[0007] In some embodiments, the detection device further includes: a first rotating component connected to the second polarizer, the first rotating component being used to drive the second polarizer to rotate around a first rotating axis, the first rotating axis being non-parallel to the polarization direction of the second polarizer, so that the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer is adjustable; or, the first rotating component is connected to both the first polarizer and the third polarizer, the first rotating component being used to drive the third polarizer to rotate around a second rotating axis, while simultaneously driving the first polarizer to rotate synchronously around the second rotating axis, the second rotating axis being non-parallel to the polarization direction of the first polarizer, so that the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer is adjustable; wherein, the first detection component is further used to generate a first image based on the first signal light, and the second detection component is further used to generate a second image based on the second signal light.

[0008] In some embodiments, the first light source is a coaxial light source, and the detection device further includes: a first beam splitter, which is used to reflect the first polarized light to the object under test and transmit the first returned light to the second polarizer, or the first beam splitter is used to transmit the first polarized light to the object under test and reflect the first returned light to the second polarizer; wherein the first polarizer is located in the optical path between the first beam splitter and the first light source, and the second polarizer is located in the optical path between the first beam splitter and the first detection component.

[0009] In some embodiments, the detection device further includes: a second light source, the second light source being used to provide second light to the second surface of the object under test; a fourth polarizer, the fourth polarizer being used to convert the second light into second polarized light, the second polarized light returning through the second surface to form second return light, the second return light passing through the third polarizer to form third signal light, the second polarized light being transmitted through the object under test to form second transmitted signal light, the second transmitted signal light passing through the second polarizer to form fourth signal light, the polarization direction of the fourth polarizer being perpendicular to the polarization direction of the second polarizer; the polarization direction of the fourth polarizer being not perpendicular to the polarization direction of the third polarizer; wherein, the second detection component is further used to receive the third signal light and generate a third image based on the third signal light, and the first detection component is further used to receive the fourth signal light and generate a fourth image based on the fourth signal light.

[0010] In some embodiments, the detection device further includes: a second rotating component connected to the third polarizer, the second rotating component being used to drive the third polarizer to rotate around a third rotating axis, the third rotating axis being non-parallel to the polarization direction of the third polarizer, so that the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer is variable; or, the second rotating component is connected to both the second polarizer and the fourth polarizer, the second rotating component being used to drive the second polarizer to rotate around a fourth rotating axis, and simultaneously drive the fourth polarizer to rotate synchronously around the fourth rotating axis, the fourth rotating axis being non-parallel to the polarization direction of the second polarizer, so that the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer is adjustable.

[0011] In some embodiments, the second light source is a coaxial light source, and the detection device further includes: a second beam splitter, which is used to reflect the second polarized light to the object under test and to transmit the first transmitted signal light and the second returned light to the third polarizer; or, the second beam splitter is used to transmit the second polarized light to the object under test and to reflect the first transmitted signal light and the second returned light to the third polarizer; wherein, the third polarizer is located in the optical path between the second beam splitter and the second detection component, and the fourth polarizer is located in the optical path between the second beam splitter and the second light source.

[0012] In some embodiments, the detection device further includes a dark field light source assembly, which includes at least one of a first dark field light source and a second dark field light source: the first dark field light source is used to provide a first dark field light to the object under test, the first dark field light being scattered by the first surface of the object under test to form a first dark field signal light; the second dark field light source is used to provide a second dark field light to the object under test, the second dark field light being scattered by the second surface of the object under test to form a second dark field signal light; the first detection component is used to receive the first dark field signal light and generate a first dark field image based on the first dark field signal light; the second detection component is used to receive the second dark field signal light and generate a second dark field image based on the second dark field signal light.

[0013] In some embodiments, the first dark field light source is a bar light source, and / or the second dark field light source is a bar light source; the detection device further includes a rotating stage, which is used to drive the test object to rotate relative to the dark field light source assembly.

[0014] In some embodiments, the first detection component includes a plurality of first detectors, which are arranged in a strip shape in the field of view of the first surface, with the fields of view of adjacent first detectors partially overlapping or staggered; the second detection component includes a plurality of second detectors, which are arranged in a strip shape in the field of view of the second surface, with the fields of view of adjacent second detectors partially overlapping or staggered; the first dark field light source is a strip light source, and the arrangement direction of the first dark field light source and the field of view of the first detectors is parallel; the second dark field light source is a strip light source, and the arrangement direction of the second dark field light source and the field of view of the second detectors is parallel.

[0015] In some embodiments, the first polarized light is reflected by the first surface to form the first returning light, and the incident direction of the first polarized light makes an acute angle with the first surface; or, the first polarized light is scattered by the first surface to form the first returning light; the second polarized light is reflected by the second surface to form the second returning light, and the incident direction of the second polarized light makes an acute angle with the second surface; or, the second polarized light is scattered by the second surface to form the second returning light.

[0016] In some embodiments, the first surface is conjugate to the photosensitive surface of the first detection component, and the second surface is conjugate to the photosensitive surface of the second detection component.

[0017] According to some embodiments of this application, another aspect of this application provides a detection method based on the detection device described in the above embodiments. The detection method includes a detection process, which includes: providing first light to the first surface of the object to be tested through a first light source; a first polarizer converting the first light into first polarized light, the first polarized light being transmitted through the object to be tested to form a first transmitted signal light, and the first polarized light returning through the first surface to form a first returned light; a second polarizer causing the first returned light to form a first signal light, the polarization direction of the second polarizer being non-perpendicular to the polarization direction of the first polarizer; the polarization direction of the third polarizer being perpendicular to the polarization direction of the first polarizer, the first transmitted signal light being transmitted through the third polarizer to form a second signal light; receiving the first signal light through a first detection component; receiving the second signal light through a second detection component; and detecting the object to be tested based on the first signal light, wherein the signal light includes one or a combination of the first signal light and the second signal light.

[0018] In some embodiments, before detecting the object under test based on the signal light, the detection process further includes: adjusting the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer to adjust the light intensity of the first signal light.

[0019] In some embodiments, the detection device further includes: a second light source, the second light source being used to provide second light to the second surface of the object under test; a fourth polarizer, the fourth polarizer converting the second light into second polarized light, the second polarized light returning through the second surface to form second return light, the second return light passing through the third polarizer to form a third signal light, the second polarized light being transmitted through the object under test to form a second transmitted signal light, the second transmitted signal light passing through the second polarizer to form a fourth signal light, the polarization direction of the fourth polarizer being perpendicular to the polarization direction of the second polarizer; the polarization direction of the fourth polarizer being not perpendicular to the polarization direction of the third polarizer; the detection process further includes: detecting the object under test based on the third signal light and the fourth signal light; before detecting the object under test based on the third signal light and the fourth signal light, the detection process further includes: adjusting the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer to adjust the light intensity of the second signal light.

[0020] In some embodiments, if the detection device further includes: a first rotating component connected to the second polarizer, or the first rotating component being connected to both the first polarizer and the third polarizer; adjusting the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer includes: controlling the first rotating component to drive the second polarizer to rotate around a first rotating axis, wherein the first rotating axis is not parallel to the polarization direction of the second polarizer; or, controlling the first rotating component to drive the third polarizer to rotate around a second rotating axis, while simultaneously driving the first polarizer to rotate synchronously around the second rotating axis to ensure that the polarization direction of the first polarizer is perpendicular to the polarization direction of the third polarizer, and the second rotating axis is not parallel to the polarization direction of the first polarizer. The detection device further includes: adjusting the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer; or, controlling the second rotating component to drive the third polarizer to rotate around a third rotation axis, wherein the third rotation axis is not parallel to the polarization direction of the third polarizer; or, controlling the second rotating component to drive the second polarizer to rotate around a fourth rotation axis, while simultaneously driving the fourth polarizer to rotate synchronously around the fourth rotation axis to ensure that the polarization direction of the second polarizer is perpendicular to the polarization direction of the fourth polarizer, wherein the fourth rotation axis is not parallel to the polarization direction of the second polarizer.

[0021] In some embodiments, detecting the object under test based on the signal light includes: acquiring detection images based on different signal lights received by the first detection component and the second detection component; and detecting and classifying the target under test based on each detection image, wherein the detected target includes defects.

[0022] In some embodiments, the detection device includes: a dark field light source assembly, the dark field light source assembly including at least one of a first dark field light source and a second dark field light source; the first dark field light source is used to provide a first dark field light to the object under test, the first dark field light being scattered by a first surface of the object under test to form a first dark field signal light, the second dark field light source is used to provide a second dark field light to the object under test, the second dark field light being scattered by a second surface of the object under test to form a second dark field signal light; the detection process further includes: receiving the first dark field signal light through a first detection component, receiving the second dark field signal light through a second detection component, the signal light further including one or a combination of the first dark field signal light and the second dark field signal light.

[0023] In some embodiments, the detection method further includes: controlling the dark field light source assembly to perform the detection process on the test object multiple times, and rotating the test object relative to the dark field light source assembly by a preset angle between adjacent detection processes, wherein the dark field light source assembly includes one or a combination of the first dark field light source and the second dark field light source; the first dark field light source is a strip light source, and / or the second dark field light source is a strip light source.

[0024] In some embodiments, detecting the object under test based on the signal light includes: controlling each light source to flash sequentially, and controlling the first detection component and the second detection component to simultaneously acquire the signal light image at a preset frequency; the preset frequency is greater than or equal to the flashing frequency of each light source, and each light source includes one or a combination of the first light source and the dark field light source component.

[0025] In some embodiments, controlling each light source to blink sequentially includes: controlling the first dark field light source and the second dark field light source to blink simultaneously, and controlling the first detection component and the second detection component to simultaneously collect the signal light at the preset frequency; the preset frequency is greater than or equal to the blinking frequency of the first dark field light source and the second dark field light source.

[0026] The technical solution provided in this application has at least the following advantages:

[0027] The detection device provided in this application includes a first light source for providing first light to a first surface of an object to be tested; a first polarizer for converting the first light into first polarized light, which is transmitted through the object to be tested to form a first transmitted signal light and returns through the first surface to form a first returned light; a second polarizer for the first returned light to form a first signal light, wherein the polarization direction of the second polarizer is not perpendicular to the polarization direction of the first polarizer; a third polarizer for the third polarizer to form a second signal light, wherein the polarization direction of the third polarizer is perpendicular to the polarization direction of the first polarizer; a first detection component for receiving the first signal light; a second detection component for receiving the second signal light; and a processor for detecting the object to be tested based on the first and second signal lights.

[0028] In the detection device provided in this application embodiment, the first light emitted by the first light source can sequentially pass through the first polarizer, the object under test, and the second polarizer to form a first signal light. The first light emitted by the first light source can also sequentially pass through the first polarizer, the object under test, and the third polarizer to form a second signal light. The processor can detect the object under test based on the first signal light and the second signal light. That is, using this detection device, two types of defect detection can be completed with one light source, which can avoid missing the detection of defect types and improve detection efficiency, thereby improving the practicality of the detection device.

[0029] Furthermore, the detection device of this application embodiment can perform two types of defect detection, allowing the inspector to perform defect detection on the test object under different types of light without changing the detection device, thereby improving detection efficiency and the practicality of the detection device. In addition, by comparing the manifestations of defects in the test object detected by different signal lights, more accurate defect classification can be achieved, which is beneficial to improving the practicality of the detection device. Attached Figure Description

[0030] One or more embodiments are illustrated by way of example with the corresponding pictures in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 is a schematic diagram of a detection device for detecting an object to be tested according to the first embodiment of this application;

[0032] Figure 2 is a top view of the field of view of the first detector and the first dark field light source in the first detection assembly in Figure 1;

[0033] Figure 3 is a bottom view of the field of view of the first detector and the second dark field light source in the first detection assembly in Figure 1.

[0034] Figure 4 is a top view of the field of view of the second detector in the second detection assembly in Figure 1 and the first dark field light source;

[0035] Figure 5 is a bottom view of the field of view of the second detector and the second dark field light source in the second detection assembly in Figure 1.

[0036] Figure 6 is a schematic diagram of a detection device for detecting the analyte provided in the second embodiment of this application;

[0037] Figure 7 is a schematic diagram of a detection device for detecting the analyte provided in the third embodiment of this application;

[0038] Figure 8 is a schematic diagram of a detection device for detecting an object to be tested according to the fourth embodiment of this application;

[0039] Figure 9 is a schematic diagram of a detection device for detecting an object to be tested according to the fifth embodiment of this application;

[0040] Figure 10 is a flowchart of the first detection method provided in the embodiment of this application;

[0041] Figure 11 is a flowchart of the second detection method provided in the embodiments of this application. Detailed Implementation

[0042] As can be seen from the background technology, the practicality of the detection devices in the relevant technologies needs to be improved.

[0043] This application provides a detection device. A first light emitted from a first light source can sequentially pass through a first polarizer, the object under test (DUT), and a second polarizer to form a first signal light. The first light emitted from the first light source can also sequentially pass through a first polarizer, the DUT, and a third polarizer to form a second signal light. A processor can detect the DUT based on the first and second signal lights. That is, this detection device can perform two types of defect detection using a single light source, avoiding missed detections of different defect types while improving detection efficiency and practicality. Furthermore, the detection device of this application can perform two types of defect detection, allowing the inspector to perform defect detection on the DUT under different types of light without changing the detection device, thereby improving detection efficiency and practicality. Additionally, by comparing the defect manifestations detected by different signal lights, more accurate defect classification can be achieved, further enhancing the practicality of the detection device.

[0044] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0045] Figure 1 is a schematic diagram of a detection device for detecting an object to be tested provided in the first embodiment of this application.

[0046] Referring to Figure 1, the detection device includes a first light source 100, a first polarizer 101, a second polarizer 102, a third polarizer 103, a first detection component 104, a second detection component 105, and a processor (not shown). The first light source 100 provides first light to the first surface 12 of the object under test 11. The first polarizer 101 converts the first light into first polarized light. The first polarized light is transmitted through the object under test 11 to form a first transmitted signal light, and the first polarized light returns through the first surface 12 to form a first returned light. The first returned light passes through the second polarizer 102 to form a first signal light. The polarization direction of the second polarizer 102 is not perpendicular to the polarization direction of the first polarizer 101. The polarization direction of the third polarizer 103 is perpendicular to the polarization direction of the first polarizer 101. The first transmitted signal light passes through the third polarizer 103 to form a second signal light. The first detection component 104 receives the first signal light. The second detection component 105 receives the second signal light. The processor detects the object under test 11 based on the first and second signal lights.

[0047] The detection device is used to detect the target of the test object 11, which includes defects.

[0048] The material of the test object 11 is a uniaxial crystal or a multiaxial crystal. Uniaxial crystals and biaxial crystals are two types of anisotropic materials. Due to their anisotropic properties, both uniaxial and biaxial crystals exhibit polarization effects when light passes through them. The detection device provides first polarized light to the test object 11, which can detect defects in the test object 11 exhibiting polarization effects under polarized light. In other embodiments of this application, the test object 11 can also be an amorphous material.

[0049] Specifically, in this embodiment, the test object 11 is a silicon carbide substrate. In other embodiments of this application, the test object 11 can be a transparent substrate such as a glass substrate or a plastic substrate, or it can be a transparent wafer, such as a sapphire wafer or a diamond wafer.

[0050] The object under test 11 has a first surface 12 and a second surface 13. The first surface 12 is conjugate with the photosensitive surface of the first detection component 104, and the second surface 13 is conjugate with the photosensitive surface of the second detection component 105. This arrangement helps the first detection component 104 to better receive the signal light emitted by the object under test 11 and generate a clearer image, and it also helps the second detection component 105 to better receive the signal light emitted by the object under test 11 and generate a clearer image, thereby improving the practicality of the detection device.

[0051] The first light source 100 is used to provide first light. In this embodiment, the first light source 100 is a coaxial light source. In other embodiments of this application, the first light source 100 can be a dark field light source.

[0052] The first polarizer 101 is used to convert the first light into first polarized light.

[0053] The first polarized light is transmitted through the test object 11 to form a first transmitted signal light, and the first polarized light is reflected back through the first surface 12 to form a first returned light. In this embodiment, the first polarized light is reflected by the first surface 12 to form the first returned light, and the incident direction of the first polarized light is perpendicular to the first surface 12. In other embodiments of this application, the first polarized light may be scattered by the first surface 12 to form the first returned light, or the first polarized light may be reflected to form the first returned light, but the incident direction of the first polarized light makes an acute angle with the first surface 12.

[0054] The polarization direction of the second polarizer 102 is not perpendicular to the polarization direction of the first polarizer 101, and the first return light is formed into the first signal light through the second polarizer 102.

[0055] The polarization direction of the third polarizer 103 is perpendicular to the polarization direction of the first polarizer 101, and the first transmitted signal light is converted into the second signal light by the third polarizer 103.

[0056] The first detection component 104 receives the first signal light and generates a first image based on the first signal light; the second detection component 105 receives the second signal light and generates a second image based on the second signal light.

[0057] In this embodiment, the detection device further includes a first beam splitter 106, which is a semi-transparent and semi-reflective mirror. The first beam splitter 106 reflects the first polarized light to the object under test 11 and transmits the first returned light to the second polarizer 102. The first polarizer 101 is located in the optical path between the first beam splitter 106 and the first light source 100, and the second polarizer 102 is located in the optical path between the first beam splitter 106 and the first detection component 104.

[0058] The detection device also includes a first rotating assembly (not shown), which is connected to the second polarizer 102. The first rotating assembly is used to drive the second polarizer 102 to rotate around a first rotating axis. The first rotating axis is not parallel to the polarization direction of the second polarizer 102, so that the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 is adjustable. Alternatively, the first rotating assembly is connected to the first polarizer 101 and the third polarizer 103 respectively. The first rotating assembly is used to drive the third polarizer 103 to rotate around a second rotating axis, and simultaneously drive the first polarizer 101 to rotate synchronously around the second rotating axis. The second rotating axis is not parallel to the polarization direction of the first polarizer 101, so that the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 is adjustable.

[0059] In other words, the first rotating component is used to adjust the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101. According to Malus's law, the light intensity of the first signal light received by the first detection component 104 is related to the angle between the polarization direction of the first polarizer 101 and the polarization direction of the second polarizer 102 on the optical path of the first light source 100 and the first detection component 104. Therefore, by adjusting the angle between the polarization direction of the first polarizer 101 and the polarization direction of the second polarizer 102, while ensuring that the first signal light has sufficient light intensity, the overexposure phenomenon of the first detection component 104 caused by excessive light intensity of the first signal light can be avoided, thereby improving the reliability of the detection device.

[0060] The first rotating component drives the first polarizer 101 and the third polarizer 103 to rotate synchronously in order to ensure that the polarization direction of the first polarizer 101 and the polarization direction of the third polarizer 103 are always perpendicular during the detection process.

[0061] The detection device also includes a dark field light source assembly, which comprises a first dark field light source 117 and a second dark field light source 127. The first dark field light source 117 provides first dark field light to the object under test 11, which is scattered by the first surface 12 of the object under test 11 to form a first dark field signal light. The second dark field light source 127 provides second dark field light to the object under test 11, which is scattered by the second surface 13 of the object under test 11 to form a second dark field signal light. A first detection component 104 receives the first dark field signal light and generates a first dark field image based on it. A second detection component 105 receives the second dark field signal light and generates a second dark field image based on it. A first beam splitter 106 further transmits the first dark field signal light to the first detection component 104.

[0062] In other embodiments of this application, the dark field light source assembly may include only one of the first dark field light source 117 and the second dark field light source 127, or the detection device may not include the first dark field light source 117 and the second dark field light source 127.

[0063] In this embodiment, the first dark field light is scattered and transmitted through the test object 11 to form the third dark field signal light. The second detection component 105 is also used to receive the third dark field signal light and generate a third dark field image based on the third dark field signal light.

[0064] It should be noted that when the object under test 11 has internal defects, the first dark-field light will be scattered within the object under test 11, and this scattered light will be transmitted to form the third dark-field signal light. Therefore, in this embodiment, the formation of the third dark-field signal light by the transmission of the first dark-field light through the object under test 11 is used to detect internal defects in the object under test 11, thereby improving the practicality of the detection device. When the object under test 11 has no internal defects, the first dark-field light will not form the third dark-field signal light after passing through the object under test 11. Therefore, in other embodiments of this application, the formation of the third dark-field signal light may not occur after the first dark-field light is scattered and transmitted through the object under test 11.

[0065] In this embodiment, the second dark field light is scattered and transmitted through the test object 11 to form the fourth dark field signal light. The first detection component 104 is also used to receive the fourth dark field signal light and generate the fourth dark field image based on the fourth dark field signal light.

[0066] It should be noted that when the object under test 11 has internal defects, the second dark-field light will be scattered within the object under test 11, and this scattered light will be transmitted to form the fourth dark-field signal light. Therefore, in this embodiment, the second dark-field light is transmitted through the object under test 11 to form the fourth dark-field signal light, which is used to detect internal defects in the object under test 11, thereby improving the practicality of the detection device. When the object under test 11 has no internal defects, the second dark-field light will not form the fourth dark-field signal light after passing through the object under test 11. Therefore, in other embodiments of this application, the second dark-field light may be scattered and transmitted through the object under test 11 without the formation of the fourth dark-field signal light.

[0067] The incident direction of the first dark field light source 117 is asymmetrical with respect to the optical axis of the first detection component 104 about the first surface 12. Specifically, there is a non-zero angle between the incident direction of the first dark field light source 117 and the optical axis of the first detection component 104, the optical axis of the first detection component 104 is perpendicular to the first surface 12, and there is an acute angle between the incident direction of the first dark field light source 117 and the normal of the first surface 12.

[0068] The incident direction of the second dark field light source 127 is asymmetrical with respect to the optical axis of the second detection component 105 about the second surface 13. Specifically, there is a non-zero angle between the incident direction of the second dark field light source 127 and the optical axis of the second detection component 105, the optical axis of the second detection component 105 is perpendicular to the second surface 13, and there is an acute angle between the incident direction of the second dark field light source 127 and the normal of the second surface 13.

[0069] In this embodiment, the first dark field light source 117 is a strip light source, and the second dark field light source 127 is a strip light source. In other embodiments of this application, the first dark field light source 117 may also be a ring light source, a surface light source, or a bowl-shaped light source, etc. The second dark field light source 127 may also be a ring light source, a surface light source, or a bowl-shaped light source, etc.

[0070] The detection device also includes a rotating stage (not shown), which is used to rotate the object under test 11 relative to the dark field light source assembly. The rotating stage allows the detection device to capture corresponding images of the signal light under first and second dark field light at multiple angles, thereby improving the practicality of the detection device.

[0071] In this embodiment, the light beam emitted by the first dark-field light source 117 is blue light; the light beam emitted by the second dark-field light source 127 is also blue light. Blue light has a shorter wavelength, and defects scatter shorter wavelength light more strongly, which is beneficial for imaging the first detection component 104 and the second detection component 105, thereby improving the practicality of the detection device. Furthermore, the shorter wavelength of blue light is advantageous for detecting defects such as small particles, which can improve the sensitivity of the detection device. In other embodiments of this application, the light beam emitted by the first dark-field light source 117 can be white light, and the light beam emitted by the second dark-field light source 127 can also be white light.

[0072] Figure 2 is a top view of the field of view of the first detector and the first dark-field light source in the first detection assembly of Figure 1. Figure 3 is a bottom view of the field of view of the first detector and the second dark-field light source in the first detection assembly of Figure 1. Figure 4 is a top view of the field of view of the second detector and the first dark-field light source in the second detection assembly of Figure 1. Figure 5 is a bottom view of the field of view of the second detector and the second dark-field light source in the second detection assembly of Figure 1. It should be noted that, for ease of illustration, only the fields of view 1041 of the three first detectors and the fields of view 1051 of the three second detectors are shown in Figures 2 to 5. In reality, the number of the first detectors and the second detectors can be any value other than 3. This application embodiment does not limit the number of the first detectors and the second detectors.

[0073] Referring to Figures 1 to 5, the first detection component 104 includes multiple first detectors, whose fields of view 1041 are arranged in a strip on the first surface 12 (i.e., the fields of view 1041 of the multiple first detectors are arranged in a strip on the first surface 12), with the fields of view 1041 of adjacent first detectors partially overlapping or staggered. The second detection component 105 includes multiple second detectors, whose fields of view 1051 are arranged in a strip on the second surface 13 (i.e., the fields of view 1051 of the multiple second detectors are arranged in a strip on the second surface), with the fields of view 1051 of adjacent second detectors partially overlapping or staggered. The first dark-field light source 117 is a strip light source, and the first dark-field light source 117 is arranged parallel to the arrangement direction of the fields of view 1041 of the first detectors. The second dark-field light source 127 is a strip light source, and the second dark-field light source 127 is arranged parallel to the arrangement direction of the fields of view 1051 of the second detectors. This arrangement gives the first detection component 104 and the second detection component 105 a large field of view, thereby improving the practicality of the detection device.

[0074] The detection device also includes a first objective lens 108 and a second objective lens 109. The first objective lens 108 is located in the optical path between the first surface 12 and the first detection component 104, and is used to focus the signal light emitted from the object under test 11 towards the first detection component 104. The second objective lens 109 is located in the optical path between the second surface 13 and the second detection component 105, and is used to focus the signal light emitted from the object under test 11 towards the second detection component 105. This arrangement can improve the imaging effect of the first detection component 104 and the second detection component 105, which is beneficial to improving the practicality of the detection device.

[0075] In this embodiment, the processor acquires detection images based on different signal lights received by the first detection component 104 and the second detection component 105, and detects and classifies the target to be tested based on each detection image. The target to be tested includes defects. The signal light includes multiple combinations of first signal light, second signal light, first dark field signal light, and second dark field light. The detection image includes multiple combinations of first image, second image, first dark field image, and second dark field image.

[0076] The second embodiment of this application also provides a detection device, which is substantially the same as the detection device provided in the first embodiment. The main difference between the second and first embodiments is that the positions of the first detection component and the first light source are different in the second embodiment. The detection device will be described in detail below with reference to the accompanying drawings. It should be noted that features that are the same as or corresponding to those in the first embodiment will not be described in detail below to avoid redundancy. Where there is no contradiction, the corresponding descriptions of the first embodiment also apply to the corresponding features of the second embodiment.

[0077] Figure 6 is a schematic diagram of a detection device for detecting an object to be tested provided in the second embodiment of this application.

[0078] Referring to Figure 6, the detection device includes: a first light source 200, a first polarizer 201, a second polarizer 202, a third polarizer 203, a first detection component 204, a second detection component 205, and a processor (not shown). The first light source 200 provides first light to the first surface 12 of the object under test 11; the first polarizer 201 converts the first light into first polarized light, which is transmitted through the object under test 11 to form a first transmitted signal light, and returns through the first surface 12 to form a first returned light; the first returned light passes through the second polarizer 202 to form a first signal light, the polarization direction of the second polarizer 202 being non-perpendicular to the polarization direction of the first polarizer 201; the polarization direction of the third polarizer 203 is perpendicular to the polarization direction of the first polarizer 201, and the first transmitted signal light passes through the third polarizer 203 to form a second signal light; the first detection component 204 receives the first signal light; the second detection component 205 receives the second signal light; and the processor detects the object under test 11 based on the first and second signal lights.

[0079] It should be noted that the dark field light source assembly, the first dark field light source 217, the second dark field light source 227, the first objective lens 208 and the second objective lens 209 in this embodiment can refer to the corresponding descriptions of the dark field light source assembly, the first dark field light source 117, the second dark field light source 127, the first objective lens 108 and the second objective lens 109 in the first embodiment, and will not be repeated here.

[0080] In this embodiment, the detection device further includes a first beam splitter 206, which is used to transmit the first polarized light to the object under test 11 and reflect the first returned light to the second polarizer 202.

[0081] The first beam splitter 206 is also used to reflect the first dark field signal light to the first detection component 204.

[0082] The third embodiment of this application also provides a detection device, which is substantially the same as the detection device provided in the first embodiment. The main difference is that the detection device provided in the third embodiment further includes a second light source and a fourth polarizer. The detection device will be described in detail below with reference to the accompanying drawings. It should be noted that features that are the same as or corresponding to those in the first embodiment will not be described in detail below to avoid redundancy. Where there is no contradiction, the corresponding descriptions of the first embodiment also apply to the corresponding features of the third embodiment.

[0083] Figure 7 is a schematic diagram of a detection device for detecting an object to be tested provided in the third embodiment of this application.

[0084] Referring to Figure 7, the detection device includes a first light source 300, a first polarizer 301, a second polarizer 302, a third polarizer 303, a first detection component 304, a second detection component 305, and a processor (not shown). The first light source 300 provides first light to the first surface 12 of the object under test 11. The first polarizer 301 converts the first light into first polarized light. The first polarized light is transmitted through the object under test 11 to form a first transmitted signal light, and the first polarized light returns through the first surface 12 to form a first returned light. The first returned light passes through the second polarizer 302 to form a first signal light. The polarization direction of the second polarizer 302 is not perpendicular to the polarization direction of the first polarizer 301. The polarization direction of the third polarizer 303 is perpendicular to the polarization direction of the first polarizer 301. The first transmitted signal light passes through the third polarizer 303 to form a second signal light. The first detection component 304 receives the first signal light. The second detection component 305 receives the second signal light. The processor detects the object under test 11 based on the first and second signal lights.

[0085] It should be noted that the first beam splitter 306, dark field light source assembly, first dark field light source 317, second dark field light source 327, first objective lens 308 and second objective lens 309 in this embodiment can refer to the corresponding descriptions of the first beam splitter 106, dark field light source assembly, first dark field light source 117, second dark field light source 127, first objective lens 108 and second objective lens 109 in the first embodiment, and will not be repeated here.

[0086] The detection device further includes a second light source 310 and a fourth polarizer 311. The second light source 310 is used to provide second light to the second surface 13 of the object under test 11. The fourth polarizer 311 is used to convert the second light into second polarized light. The second polarized light returns through the second surface 13 to form a second return light. The second return light passes through a third polarizer 303 to form a third signal light. The second polarized light is transmitted through the object under test 11 to form a second transmitted signal light. The second transmitted signal light passes through a second polarizer to form a fourth signal light. The polarization direction of the fourth polarizer 311 is perpendicular to the polarization direction of the second polarizer 302. The polarization direction of the fourth polarizer 311 is not perpendicular to the polarization direction of the third polarizer 303. The second detection component is also used to receive the third signal light and generate a third image based on the third signal light. The first detection component is also used to receive the fourth signal light and generate a fourth image based on the fourth signal light.

[0087] In this embodiment, the second light source 310 is a coaxial light source. In other embodiments of this application, the second light source 310 can be a dark field light source.

[0088] The second light source 310 is used to provide a second light. In this embodiment, the second light source 310 is a coaxial light source. In other embodiments of this application, the second light source 310 can be a dark field light source.

[0089] The fourth polarizer 311 is used to convert the second light into second polarized light. In this embodiment, the second polarized light is reflected by the second surface 13 to form the second return light, and the incident direction of the second polarized light is perpendicular to the second surface 13. In other embodiments of this application, the second polarized light may be scattered by the second surface 13 to form the second return light, or the second polarized light may be reflected to form the second return light, but the incident direction of the second polarized light makes an acute angle with the second surface 13.

[0090] The detection device also includes a second rotating assembly (not shown), which is connected to the third polarizer 303. The second rotating assembly is used to drive the third polarizer 303 to rotate around a third rotating axis. The third rotating axis is not parallel to the polarization direction of the third polarizer 303, so that the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311 is variable. Alternatively, the second rotating assembly is connected to the second polarizer 302 and the fourth polarizer 311 respectively. The second rotating assembly is used to drive the second polarizer 302 to rotate around a fourth rotating axis, and simultaneously drive the fourth polarizer 311 to rotate synchronously around the fourth rotating axis. The fourth rotating axis is not parallel to the polarization direction of the second polarizer 302, so that the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311 is adjustable.

[0091] In other words, the second rotating component is used to adjust the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311. According to Malus's law, the intensity of the third signal light received by the second detection component 305 is related to the angle between the polarization directions of the third polarizer 303 and the fourth polarizer 311 on the optical path of the second light source 310 and the second detection component. Therefore, by adjusting the angle between the polarization directions of the third polarizer 303 and the fourth polarizer 311, while ensuring sufficient intensity of the third signal light, overexposure of the second detection component 305 caused by excessively high intensity of the third signal light can be avoided, thus improving the reliability of the detection device.

[0092] The second rotating component drives the second polarizer 302 and the fourth polarizer 311 to rotate synchronously in order to ensure that the polarization direction of the second polarizer 302 and the polarization direction of the fourth polarizer 311 are always perpendicular.

[0093] The detection device also includes a second beam splitter 312, which is a semi-transparent and semi-reflective mirror. The second beam splitter 312 is used to reflect the second polarized light to the object under test 11 and to transmit the first transmitted signal light and the second returned light to the third polarizer 303. The third polarizer 303 is located in the optical path between the second beam splitter 312 and the second detection component, and the fourth polarizer 311 is located in the optical path between the second beam splitter 312 and the second light source 310.

[0094] The fourth embodiment of this application also provides a detection device, which is substantially the same as the detection device provided in the third embodiment. The main difference is that the positions of the second detection component and the second coaxial light source in the detection device provided in the fourth embodiment are different from those in the first embodiment. The detection device will be described in detail below with reference to the accompanying drawings. It should be noted that features that are the same as or corresponding to those in the third embodiment will not be described in detail below to avoid redundancy. Where there is no contradiction, the corresponding descriptions of the third embodiment also apply to the corresponding features of the fourth embodiment.

[0095] Figure 8 is a schematic diagram of a detection device for detecting an object to be tested provided in the fourth embodiment of this application.

[0096] Referring to Figure 8, the detection device includes a first light source 400, a first polarizer 401, a second polarizer 402, a third polarizer 403, a first detection component 404, a second detection component 405, and a processor (not shown). The first light source 400 provides first light to the first surface 12 of the object under test 11. The first polarizer 401 converts the first light into first polarized light. The first polarized light is transmitted through the object under test 11 to form a first transmitted signal light, and the first polarized light returns through the first surface 12 to form a first returned light. The first returned light passes through the second polarizer 402 to form a first signal light. The polarization direction of the second polarizer 402 is not perpendicular to the polarization direction of the first polarizer 401. The polarization direction of the third polarizer 403 is perpendicular to the polarization direction of the first polarizer 401. The first transmitted signal light passes through the third polarizer 403 to form a second signal light. The first detection component 404 receives the first signal light. The second detection component 405 receives the second signal light. The processor detects the object under test 11 based on the first and second signal lights.

[0097] It should be noted that the first beam splitter 406, dark field light source assembly, first dark field light source 417, second dark field light source 427, first objective lens 408, second objective lens 409, second light source 410 and fourth polarizer 411 in this embodiment can be referred to the corresponding descriptions of the first beam splitter 306, dark field light source assembly, first dark field light source 317, second dark field light source 327, first objective lens 308, second objective lens 309, second light source 310 and fourth polarizer 311 in the third embodiment, and will not be repeated here.

[0098] In this embodiment, the detection device further includes a second beam splitter 412, which is a semi-transparent and semi-reflective mirror. The second beam splitter 412 is used to transmit the second polarized light to the object under test 11 and to reflect the first transmitted signal light and the second returned light to the third polarizer 403.

[0099] The fifth embodiment of this application also provides a detection device, which is substantially the same as the detection device provided in the third embodiment. The main difference is that the first light source and the second light source in the detection device provided in the fifth embodiment are both dark field light sources. The detection device will be described in detail below with reference to the accompanying drawings. It should be noted that features that are the same as or corresponding to those in the third embodiment will not be described in detail below to avoid redundancy. In the absence of contradiction, the corresponding descriptions of the third embodiment are also applicable to the corresponding features of the fifth embodiment.

[0100] Figure 9 is a schematic diagram of a detection device for detecting an object to be tested provided in the fifth embodiment of this application.

[0101] Referring to Figure 9, the detection device includes a first light source 500, a first polarizer 501, a second polarizer 502, a third polarizer 503, a first detection component 504, a second detection component 505, and a processor (not shown). The first light source 500 provides first light to the first surface 12 of the object under test 11. The first polarizer 501 converts the first light into first polarized light. The first polarized light is transmitted through the object under test 11 to form a first transmitted signal light, and the first polarized light returns through the first surface 12 to form a first returned light. The first returned light passes through the second polarizer 502 to form a first signal light. The polarization direction of the second polarizer 502 is not perpendicular to the polarization direction of the first polarizer 501. The polarization direction of the third polarizer 503 is perpendicular to the polarization direction of the first polarizer 501. The first transmitted signal light passes through the third polarizer 503 to form a second signal light. The first detection component 504 receives the first signal light. The second detection component 505 receives the second signal light. The processor detects the object under test 11 based on the first and second signal lights.

[0102] The detection device further includes a second light source 510 and a fourth polarizer 511. The second light source 510 is used to provide second light to the second surface 13 of the object under test 11. The fourth polarizer 511 is used to convert the second light into second polarized light. The second polarized light returns through the second surface 13 to form second return light. The second return light passes through a third polarizer 503 to form a third signal light. The second polarized light is transmitted through the object under test 11 to form a second transmitted signal light. The second transmitted signal light passes through a second polarizer to form a fourth signal light. The polarization direction of the fourth polarizer 511 is perpendicular to the polarization direction of the second polarizer 502. The polarization direction of the fourth polarizer 511 is not perpendicular to the polarization direction of the third polarizer 503. The second detection component 505 is also used to receive the third signal light and generate a third image based on the third signal light. The first detection component 504 is also used to receive the fourth signal light and generate a fourth image based on the fourth signal light.

[0103] In this embodiment, the first light source 500 is a dark field light source. In other embodiments of this application, the first light source may also be a bright field light source.

[0104] In this embodiment, the second light source 510 is a dark field light source. In other embodiments of this application, the second light source may also be a bright field light source.

[0105] In this embodiment, the first polarized light is scattered by the first surface 12 to form the first returned light, and the second polarized light is scattered by the second surface 13 to form the second returned light. In other embodiments of this application, the first polarized light can be reflected by the first surface 12 to form the first returned light, and the incident direction of the first polarized light forms an acute angle with the first surface 12; the second polarized light is reflected by the second surface 13 to form the second returned light, and the incident direction of the second polarized light forms an acute angle with the second surface 13.

[0106] In the aforementioned detection device, the first light emitted by the first light source can sequentially pass through a first polarizer, the object under test, and a second polarizer to form a first signal light. The first light emitted by the first light source can also sequentially pass through a first polarizer, the object under test, and a third polarizer to form a second signal light. The processor can detect the object under test based on the first and second signal lights. That is, this detection device can perform two types of defect detection using a single light source, avoiding missed detections of different defect types while improving detection efficiency and the practicality of the detection device. Furthermore, the detection device of this application embodiment can perform two types of defect detection, allowing the inspector to perform defect detection of the object under different types of light without changing the detection device, thereby improving detection efficiency and the practicality of the detection device. Additionally, by comparing the manifestations of defects in the object under test detected by different signal lights, more accurate defect classification can be achieved, which is beneficial to improving the practicality of the detection device.

[0107] According to some embodiments of this application, another aspect of this application provides a detection method based on the detection apparatus of any of the above embodiments. For parts that are the same as or corresponding to the previous embodiment, please refer to the corresponding descriptions of the foregoing embodiments, which will not be repeated in detail below.

[0108] Referring to Figure 1, the detection device includes a first light source 100, a first polarizer 101, a second polarizer 102, a third polarizer 103, a first detection component 104, and a second detection component 105. The first light source 100 provides first light to the first surface 12 of the object under test 11. The first polarizer 101 converts the first light into first polarized light. The first polarized light is transmitted through the object under test 11 to form a first transmitted signal light, and the first polarized light returns through the first surface 12 to form a first returned light. The first returned light passes through the second polarizer 102 to form a first signal light. The polarization direction of the second polarizer 102 is not perpendicular to the polarization direction of the first polarizer 101. The polarization direction of the third polarizer 103 is perpendicular to the polarization direction of the first polarizer 101. The first transmitted signal light passes through the third polarizer 103 to form a second signal light. The first detection component 104 receives the first signal light. The second detection component 105 receives the second signal light.

[0109] Figure 10 is a flowchart of the first detection method provided in the embodiments of this application.

[0110] The first detection method provided in this application includes a detection process, the steps of which include:

[0111] Referring to Figures 1 and 10, a first light source 100 provides first light to the first surface 12 of the object under test 11; a first polarizer 101 converts the first light into first polarized light, which is transmitted through the object under test 11 to form a first transmitted signal light, and returns through the first surface 12 to form a first returned light; a second polarizer 102 causes the first returned light to form a first signal light, the polarization direction of the second polarizer 102 is not perpendicular to the polarization direction of the first polarizer 101, and the polarization direction of the third polarizer 103 is perpendicular to the polarization direction of the first polarizer 101, the first transmitted signal light is transmitted through the third polarizer 103 to form a second signal light; the first signal light is received by a first detection component 104; the second signal light is received by a second detection component 105; the object under test 11 is detected according to the signal light, the signal light including one or more combinations of the first signal light and the second signal light.

[0112] The detection of the object to be tested 11 based on the signal light includes: acquiring detection images based on different signal lights received by the first detection component 104 and the second detection component 105; and detecting and classifying the target to be tested based on each detection image, including defects.

[0113] Before detecting the object under test based on the signal light, the method further includes: adjusting the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 to adjust the light intensity of the first signal light.

[0114] According to Malus's law, the intensity of the first signal light is related to the angle between the polarization direction of the first polarizer 101 and the polarization direction of the second polarizer 102. Therefore, the intensity of the first signal light can be adjusted by adjusting the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101. This ensures that the first signal light has sufficient intensity while preventing the first detection component 104 from being overexposed, thereby improving the reliability of the detection.

[0115] Specifically, in this embodiment, the detection device further includes: a first rotating component (not shown), which is connected to the second polarizer 102. Adjusting the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 includes controlling the first rotating component to drive the second polarizer 102 to rotate around a first rotating axis. The first rotating axis is not parallel to the polarization direction of the second polarizer 102.

[0116] In other embodiments of this application, the first rotating component may also be connected to the first polarizer 101 and the third polarizer 103 respectively. Adjusting the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 includes: controlling the first rotating component to drive the third polarizer 103 to rotate around the second rotation axis, while simultaneously driving the first polarizer 101 to rotate synchronously around the second rotation axis, so as to ensure that the polarization direction of the first polarizer 101 is perpendicular to the polarization direction of the third polarizer 103. Wherein, the second rotation axis is not parallel to the polarization direction of the first polarizer 101.

[0117] The detection device also includes a dark field light source assembly, which includes a first dark field light source 117 and a second dark field light source 127. The first dark field light source 117 is used to provide a first dark field light to the test object 11, and the first dark field light is scattered by the first surface 12 of the test object 11 to form a first dark field signal light. The second dark field light source 127 is used to provide a second dark field light to the test object 11, and the second dark field light is scattered by the second surface 13 of the test object 11 to form a second dark field signal light.

[0118] In this embodiment, the dark field light source assembly includes a first dark field light source 117 and a second dark field light source 127. In other embodiments of this application, the dark field light source assembly may include only one of the first dark field light source and the second dark field light source. When detecting the object under test based on the signal light, detection can be performed using only one of the first dark field signal light and the second dark field signal light.

[0119] The detection method further includes: controlling the dark field light source assembly to perform multiple detection processes on the object 11, and rotating the object 11 relative to the dark field light source assembly by a preset angle between adjacent detection processes. The dark field light source assembly includes one or a combination of a first dark field light source 117 and a second dark field light source 127; the first dark field light source is a bar light source, and / or the second dark field light source is a bar light source. This configuration allows the detection device to collect corresponding signal light under the first dark field light and / or the second dark field light at multiple angles, thereby improving the accuracy and comprehensiveness of the detection.

[0120] Referring to steps S101 and S102 in Figures 1 and 10, before detecting the object 11 based on the signal light, the detection process further includes: controlling each light source to flash sequentially, and controlling the first detection component 104 and the second detection component 105 to simultaneously collect the signal light at a preset frequency; the preset frequency is greater than or equal to the flashing frequency of each light source, and each light source includes one or a combination of the first light source 100 and the dark field light source component. The signal light includes one or a combination of the first signal light, the second signal light, the first dark field signal light, and the second dark field signal light. By controlling the sequential flashing of each light source, the test object 11 can sequentially complete defect detection under different light sources. This setup allows for the detection of multiple types of defects in the test object 11, reducing missed defects and improving the practicality of the detection device. Furthermore, controlling the sequential flashing of each light source eliminates the need for the operator to change the detection equipment, allowing for defect detection of the test object 11 under multiple light sources, thus reducing detection time and further enhancing the device's usability. Some defects in the test object 11 can be detected under multiple light sources; by comparing the defect manifestations under different light sources, more accurate defect classification can be achieved, further improving the device's practicality. Additionally, setting a preset frequency greater than or equal to the flashing frequency of the light source ensures that the signal light emitted by each test object 11 under the corresponding light source flashing is collected by the first detection component 104 and the second detection component 105, improving the reliability of the detection device.

[0121] Controlling each light source to blink sequentially includes: controlling the first dark field light source 117 and the second dark field light source 127 to blink simultaneously, and controlling the first detection component 104 and the second detection component 105 to simultaneously collect signal light at a preset frequency; the preset frequency is greater than or equal to the blinking frequency of the first dark field light source 117 and the second dark field light source 127.

[0122] Simultaneous flashing of the first dark-field light source 117 and the second dark-field light source 127 can save testing time and improve testing efficiency. A preset frequency greater than or equal to the flashing frequency of the first dark-field light source 117 and the second dark-field light source 127 ensures that the signal light emitted by each test object 11 under the flashing of the first dark-field light source 117 and the second dark-field light source 127 is collected by the first detection component 104 and the second detection component 105, thereby improving the reliability of the detection device.

[0123] In other embodiments of this application, the first dark field light source 117 and the second dark field light source 127 may not flash simultaneously.

[0124] Before the detection process, the detection method further includes: performing a first pre-detection on the detection device to determine a first matching angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101; the pre-detection includes: continuously adjusting the first measured angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101, and acquiring a first signal light through the first detection component 104; acquiring the first measured angle where the first detection component 104 is not overexposed and reaches a preset sensitivity as the first matching angle. Adjusting the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 to adjust the light intensity of the first signal light includes: making the angle between the polarization direction of the second polarizer 102 and the polarization direction of the first polarizer 101 the first matching angle.

[0125] Specifically, referring to Figure 10, the first detection method provided in this embodiment includes:

[0126] Step S100: Adjust the angle between the polarization direction of the first polarizer and the polarization direction of the second polarizer.

[0127] Step S101: Control the first light source and the dark field light source assembly to flash sequentially, so as to provide first light to the first surface of the object under test through the first light source. The first polarizer converts the first light into first polarized light. The first polarized light returns through the first surface to form first return light. The second polarizer causes the first return light to form first signal light. The first polarized light is transmitted through the object under test to form first transmitted signal light. The first transmitted signal light is transmitted through the third polarizer to form second signal light. The first dark field light is provided to the object under test through the first dark field light source in the dark field light source assembly. The first dark field light is scattered by the object under test to form first dark field signal light. The second dark field light is provided to the object under test through the second dark field light source in the dark field light source assembly. The second dark field light is scattered by the object under test to form second dark field signal light.

[0128] Step S102: Control the first detection component and the second detection component to simultaneously collect signal light at a preset frequency, wherein the preset frequency is greater than or equal to the flicker frequency of the first light source and the dark field light source component.

[0129] Step S103: Detect the object to be tested based on the signal light.

[0130] This application also provides a second detection method, which is substantially the same as the first detection method. The main difference is that the detection device for the second detection method further includes a second light source and a fourth polarizer. The second detection method also detects the object under test based on a third signal light and a fourth signal light, and the intensity of the third signal light is adjusted before detecting the object under test. The detection device will be described in detail below with reference to the accompanying drawings. It should be noted that features that are the same as or corresponding to those in the first detection method will not be described in detail below to avoid redundancy. Where there is no contradiction, the corresponding descriptions of the first detection method also apply to the corresponding features of the second detection method.

[0131] Figure 11 is a flowchart of the second detection method provided in the embodiments of this application.

[0132] The second detection method provided in this application includes a detection process, the steps of which include:

[0133] Referring to Figures 7 and 11, a first light source 300 provides first light to the first surface 12 of the object under test 11; a first polarizer 301 converts the first light into first polarized light, which is transmitted through the object under test 11 to form a first transmitted signal light, and returns through the first surface 12 to form a first returned light; a second polarizer 302 causes the first returned light to form a first signal light, the polarization direction of the second polarizer 302 being non-perpendicular to the polarization direction of the first polarizer 301; a third polarizer 303 has a polarization direction perpendicular to the polarization direction of the first polarizer 301, and the first transmitted signal light is transmitted through the third polarizer 303 to form a second signal light; the first signal light is received by a first detection component 304; the second signal light is received by a second detection component 305; and the object under test 11 is detected based on the signal light, which includes one or more combinations of the first and second signal lights.

[0134] Before detecting the object under test based on the signal light, the detection process also includes: adjusting the angle between the polarization direction of the second polarizer 302 and the polarization direction of the first polarizer 301 to adjust the light intensity of the first signal light.

[0135] According to Malus's law, the intensity of the first signal light is related to the angle between the polarization direction of the first polarizer 301 and the polarization direction of the second polarizer 302. Therefore, the intensity of the first signal light can be adjusted by adjusting the angle between the polarization direction of the second polarizer 302 and the polarization direction of the first polarizer 301. This ensures that the first signal light has sufficient intensity while preventing the first detection component 304 from being overexposed, thereby improving the reliability of the detection device.

[0136] Specifically, in this embodiment, the detection device further includes: a first rotating component (not shown), which is connected to the second polarizer 302. Adjusting the angle between the polarization direction of the second polarizer 302 and the polarization direction of the first polarizer 301 includes controlling the first rotating component to drive the second polarizer 302 to rotate around a first rotating axis. The first rotating axis is not parallel to the polarization direction of the second polarizer 302.

[0137] In other embodiments of this application, the first rotating component may also be connected to the first polarizer 301 and the third polarizer 303 respectively. Adjusting the angle between the polarization direction of the second polarizer 302 and the polarization direction of the first polarizer 301 includes: controlling the first rotating component to drive the third polarizer 303 to rotate around the second rotation axis, while simultaneously driving the first polarizer 301 to rotate synchronously around the second rotation axis, so as to ensure that the polarization direction of the first polarizer 301 is perpendicular to the polarization direction of the third polarizer 303. Wherein, the second rotation axis is not parallel to the polarization direction of the first polarizer 301.

[0138] The detection device also includes a second light source 310 and a fourth polarizer 311. The second light source 310 provides second light to the second surface 13 of the test object 11. The fourth polarizer 311 converts the second light into second polarized light. The second polarized light returns through the second surface 13 to form second return light. The second return light passes through a third polarizer 303 to form a third signal light. The second polarized light is transmitted through the test object 11 to form a second transmitted signal light. The second transmitted signal light passes through a second polarizer 302 to form a fourth signal light. The polarization direction of the fourth polarizer 311 is perpendicular to the polarization direction of the second polarizer 302. The polarization direction of the fourth polarizer 311 is not perpendicular to the polarization direction of the third polarizer 303.

[0139] The detection process also includes: detecting the object 11 under test based on the third signal light and the fourth signal light; before detecting the object 11 under test based on the third signal light and the fourth signal light, the detection process also includes: adjusting the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311 to adjust the light intensity of the second signal light.

[0140] According to Malus's law, the intensity of the second signal light is related to the angle between the polarization directions of the third polarizer 303 and the fourth polarizer 311. Therefore, the intensity of the second signal light can be adjusted by changing the angle between the polarization directions of the third polarizer 303 and the fourth polarizer 311. This ensures that the second signal light has sufficient intensity while preventing overexposure of the second detection component 305, thereby improving the reliability of the detection.

[0141] Specifically, in this embodiment, the detection device further includes a second rotating component (not shown), which is connected to the third polarizer 303. Adjusting the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311 includes controlling the second rotating component to drive the third polarizer 303 to rotate around a third rotating axis. The third rotating axis is not parallel to the polarization direction of the third polarizer 303.

[0142] In other embodiments of this application, the second rotating assembly is connected to both the second polarizer 302 and the fourth polarizer 311. The second rotating assembly is controlled to rotate the second polarizer 302 around a fourth rotation axis, and simultaneously rotate the fourth polarizer 311 around the fourth rotation axis to ensure that the polarization direction of the second polarizer 302 is perpendicular to the polarization direction of the fourth polarizer 311. The fourth rotation axis is not parallel to the polarization direction of the second polarizer 302.

[0143] The detection of the object under test 11 based on the signal light includes: acquiring detection images based on different signal lights received by the first detection component 304 and the second detection component 305; and detecting and classifying the target under test based on each detection image, including defects.

[0144] The detection device also includes a dark field light source assembly, which includes a first dark field light source 317 and a second dark field light source 327. The first dark field light source 317 is used to provide a first dark field light to the test object 11. The first dark field light is scattered by the first surface 12 of the test object 11 to form a first dark field signal light. The second dark field light source 327 is used to provide a second dark field light to the test object 11. The second dark field light is scattered by the second surface 13 of the test object 11 to form a second dark field signal light. The detection process also includes: receiving the first dark field signal light through a first detection component 304 and receiving the second dark field signal light through a second detection component receiving 305. The signal light also includes one or a combination of the first dark field signal light and the second dark field signal light.

[0145] In this embodiment, the dark field light source assembly includes a first dark field light source 317 and a second dark field light source 327. In other embodiments of this application, the dark field light source assembly may include only one of the first dark field light source and the second dark field light source. When detecting the object under test based on the signal light, detection can be performed using only one of the first dark field signal light and the second dark field signal light.

[0146] The detection method further includes: controlling the dark field light source assembly to perform multiple detection processes on the test object 11, and rotating the test object 11 relative to the dark field light source assembly by a preset angle between adjacent detection processes; the dark field light source assembly includes one or a combination of a first dark field light source 317 and a second dark field light source 327; the first dark field light source 317 is a bar light source, and / or, the second dark field light source 327 is a bar light source. This configuration allows the detection device to collect corresponding signal light under the first dark field light and / or the second dark field light at multiple angles, thereby improving the reliability of the test.

[0147] Referring to steps S201 and S202 in Figures 7 and 11, before detecting the object 11 based on the signal light, the process includes: controlling each light source to flash sequentially, and controlling the first detection component 304 and the second detection component 305 to simultaneously collect the signal light at a preset frequency; the preset frequency is greater than or equal to the flashing frequency of each light source, and each light source includes one or more combinations of the first light source 300, the second light source 310, and the dark field light source component. The signal light includes one or more combinations of the first signal light, the second signal light, the third signal light, the fourth signal light, the first dark field signal light, and the second dark field signal light. By controlling the sequential flashing of each light source, the test object 11 can sequentially complete defect detection under different light sources. This setup allows for the detection of multiple types of defects in the test object 11, reducing missed defects and improving the practicality of the detection device. Furthermore, controlling the sequential flashing of each light source eliminates the need for the operator to change the detection equipment, allowing for defect detection of the test object 11 under multiple light sources, thus reducing detection time and further enhancing the device's usability. Some defects in the test object 11 can be detected under multiple light sources; by comparing the defect manifestations under different light sources, more accurate defect classification can be achieved, further improving the device's practicality. Additionally, a preset frequency greater than or equal to the flashing frequency of the light source ensures that the signal light emitted by each test object 11 under the corresponding light source flashing is collected by the first detection component 304 and the second detection component 305, improving detection reliability.

[0148] Controlling the sequential flashing of each light source includes: controlling the first dark field light source 317 and the second dark field light source 327 to flash simultaneously, and controlling the first detection component 304 and the second detection component 305 to simultaneously collect signal light at a preset frequency; the preset frequency is greater than or equal to the flashing frequency of the first dark field light source 317 and the second dark field light source 327. This setting can save testing time and improve testing efficiency.

[0149] In other embodiments of this application, the first dark field light source 317 and the second dark field light source 327 may not flash simultaneously.

[0150] Before the detection process, the detection method further includes: performing a second pre-detection on the detection device to determine a second matching angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311; the pre-detection includes: continuously adjusting the second measured angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311, and acquiring a second signal light through the second detection component 305; acquiring the second measured angle where the second detection component 305 is not overexposed and reaches a preset sensitivity as the second matching angle. Adjusting the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311 to adjust the light intensity of the second signal light includes: making the angle between the polarization direction of the third polarizer 303 and the polarization direction of the fourth polarizer 311 the second matching angle.

[0151] Specifically, referring to Figure 11, the second detection method provided in this application embodiment includes:

[0152] Step S200: Adjust the angle between the polarization direction of the first polarizer and the polarization direction of the second polarizer, and adjust the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer.

[0153] Step S201: Control the first light source, the second light source, and the dark field light source assembly to flash sequentially, so as to provide first light to the first surface of the object under test through the first light source, the first polarizer converts the first light into first polarized light, the first polarized light returns through the first surface to form first return light, the second polarizer causes the first return light to form first signal light, the first polarized light is transmitted through the object under test to form first transmitted signal light, and the first transmitted signal light is transmitted through the third polarizer to form second signal light; provide second light to the second surface of the object under test through the second light source, the fourth polarizer converts the second light into second polarized light, the second polarized light returns through the second surface to form second return light, the second return light is transmitted through the third polarizer to form third signal light, the second polarized light is transmitted through the object under test to form second transmitted signal light, and the second transmitted signal light is transmitted through the second polarizer to form fourth signal light; provide first dark field light to the object under test through the first dark field light source in the dark field light source assembly, the first dark field light is scattered by the object under test to form first dark field signal light, and provide second dark field light to the object under test through the second dark field light source in the dark field light source assembly, the second dark field light is scattered by the object under test to form second dark field signal light.

[0154] Step S202: Control the first detection component and the second detection component to simultaneously collect signal light at a preset frequency, wherein the preset frequency is greater than or equal to the flicker frequency of the first light source, the second light source and the dark field light source component.

[0155] Step S203: Detect the object under test based on the signal light.

[0156] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A detection device for detecting an object to be tested, the object to be tested comprising a first surface and a second surface opposite to each other, the detection device comprising: A first light source is used to provide first light to the first surface of the object under test; A first polarizer is used to convert the first light into first polarized light. The first polarized light is transmitted through the object under test to form a first transmitted signal light, and the first polarized light is returned through the first surface to form a first returned light. The second polarizer is used to form the first signal light by passing the first return light through the second polarizer. The polarization direction of the second polarizer is not perpendicular to the polarization direction of the first polarizer. A third polarizer, wherein the polarization direction of the third polarizer is perpendicular to the polarization direction of the first polarizer, and the first transmitted signal light is converted into second signal light by the third polarizer; A first detection component, the first detection component being used to receive the first signal light; A second detection component, the second detection component being used to receive the second signal light; A processor is used to detect the object under test based on the first signal light and the second signal light.

2. The detection device according to claim 1, wherein, The detection device further includes: A first rotating assembly is connected to the second polarizer. The first rotating assembly is used to drive the second polarizer to rotate around a first rotating axis. The first rotating axis is not parallel to the polarization direction of the second polarizer, so that the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer is adjustable. Alternatively, the first rotating assembly is connected to both the first polarizer and the third polarizer. The first rotating assembly is used to drive the third polarizer to rotate around a second rotating axis, while simultaneously driving the first polarizer to rotate synchronously around the second rotating axis. The second rotating axis is not parallel to the polarization direction of the first polarizer, so that the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer is adjustable. The first detection component is further configured to generate a first image based on the first signal light, and the second detection component is further configured to generate a second image based on the second signal light.

3. The detection device according to claim 2, wherein, The first light source is a coaxial light source, and the detection device further includes: A first beam splitter is used to reflect the first polarized light to the object under test and transmit the first returned light to the second polarizer; or, the first beam splitter is used to transmit the first polarized light to the object under test and reflect the first returned light to the second polarizer. The first polarizer is located in the optical path between the first beam splitter and the first light source, and the second polarizer is located in the optical path between the first beam splitter and the first detection component.

4. The detection device according to any one of claims 1 to 3, wherein, The detection device further includes: A second light source is used to provide second light to the second surface of the object under test; A fourth polarizer is used to convert the second light into second polarized light. The second polarized light returns through the second surface to form a second return light. The second return light passes through the third polarizer to form a third signal light. The second polarized light is transmitted through the object under test to form a second transmitted signal light. The second transmitted signal light passes through the second polarizer to form a fourth signal light. The polarization direction of the fourth polarizer is perpendicular to the polarization direction of the second polarizer; the polarization direction of the fourth polarizer is not perpendicular to the polarization direction of the third polarizer. The second detection component is further configured to receive the third signal light and generate a third image based on the third signal light, and the first detection component is further configured to receive the fourth signal light and generate a fourth image based on the fourth signal light.

5. The detection device according to claim 4, wherein, The detection device further includes: A second rotating assembly is connected to the third polarizer. The second rotating assembly drives the third polarizer to rotate around a third rotation axis. The third rotation axis is not parallel to the polarization direction of the third polarizer, so that the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer is variable. Alternatively, the second rotating assembly is connected to both the second polarizer and the fourth polarizer. The second rotating assembly drives the second polarizer to rotate around a fourth rotation axis, and simultaneously drives the fourth polarizer to rotate synchronously around the fourth rotation axis. The fourth rotation axis is not parallel to the polarization direction of the second polarizer, so that the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer is adjustable.

6. The detection device according to claim 5, wherein, The second light source is a coaxial light source, and the detection device further includes: The second beam splitter is used to reflect the second polarized light to the object under test and to transmit the first transmitted signal light and the second returned light to the third polarizer; or, the second beam splitter is used to transmit the second polarized light to the object under test and to reflect the first transmitted signal light and the second returned light to the third polarizer. The third polarizer is located in the optical path between the second beam splitter and the second detection component, and the fourth polarizer is located in the optical path between the second beam splitter and the second light source.

7. The detection device according to claim 1, wherein, The detection device further includes a dark field light source assembly, which includes at least one of a first dark field light source and a second dark field light source. The first dark-field light source provides first dark-field light to the object under test (AUT), and the first dark-field light is scattered by the first surface of the AUT to form first dark-field signal light. The second dark-field light source provides second dark-field light to the AUT, and the second dark-field light is scattered by the second surface of the AUT to form second dark-field signal light. The first detection component is used to receive the first dark field signal light and generate a first dark field image based on the first dark field signal light; the second detection component is used to receive the second dark field signal light and generate a second dark field image based on the second dark field signal light.

8. The detection device according to claim 7, wherein, The first dark field light source is a bar light source, and / or the second dark field light source is a bar light source; the detection device further includes a rotating stage, which is used to drive the test object to rotate relative to the dark field light source assembly.

9. The detection device according to claim 8, wherein, The first detection component includes a plurality of first detectors, which are arranged in a strip shape in the field of view of the first surface, with the fields of view of adjacent first detectors partially overlapping or staggered. The second detection component includes a plurality of second detectors, which are arranged in a strip shape in the field of view of the second surface, with the fields of view of adjacent second detectors partially overlapping or staggered. The first dark field light source is a strip light source, and the arrangement direction of the first dark field light source and the field of view of the first detector are parallel; the second dark field light source is a strip light source, and the arrangement direction of the second dark field light source and the field of view of the second detector are parallel.

10. The detection device according to claim 4, wherein, The first polarized light is reflected by the first surface to form the first returning light, and the incident direction of the first polarized light makes an acute angle with the first surface, or the first polarized light is scattered by the first surface to form the first returning light; The second polarized light is reflected by the second surface to form the second returning light, and the incident direction of the second polarized light makes an acute angle with the second surface, or the second polarized light is scattered by the second surface to form the second returning light.

11. The detection device according to claim 1, wherein, The first surface is conjugate to the photosensitive surface of the first detection component, and the second surface is conjugate to the photosensitive surface of the second detection component.

12. A detection method based on the detection apparatus according to any one of claims 1 to 11, for detecting a test object, the test object comprising opposing first and second surfaces, the detection method comprising a detection process, the detection process comprising: A first light is provided to the first surface of the object under test by a first light source; The first polarizer converts the first light into first polarized light, the first polarized light is transmitted through the object under test to form a first transmitted signal light, and the first polarized light returns through the first surface to form a first returned light. The second polarizer causes the first returned light to form the first signal light, and the polarization direction of the second polarizer is not perpendicular to the polarization direction of the first polarizer; the polarization direction of the third polarizer is perpendicular to the polarization direction of the first polarizer, and the first transmitted signal light is formed into the second signal light by the third polarizer. The first signal light is received by the first detection component; The second signal light is received by the second detection component; The test object is detected based on the signal light, wherein the signal light includes one or a combination of the first signal light and the second signal light.

13. The detection method according to claim 12, wherein, Before detecting the analyte based on the signal light, the detection process further includes: Adjust the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer to adjust the light intensity of the first signal light.

14. The detection method according to claim 12, wherein, If the detection device further includes: a second light source, the second light source being used to provide second light to the second surface of the object under test; a fourth polarizer, the fourth polarizer converting the second light into second polarized light, the second polarized light returning through the second surface to form second return light, the second return light passing through the third polarizer to form third signal light, the second polarized light being transmitted through the object under test to form second transmitted signal light, the second transmitted signal light passing through the second polarizer to form fourth signal light, the polarization direction of the fourth polarizer being perpendicular to the polarization direction of the second polarizer; the polarization direction of the fourth polarizer being not perpendicular to the polarization direction of the third polarizer; The detection process further includes: detecting the object under test based on the third signal light and the fourth signal light; before detecting the object under test based on the third signal light and the fourth signal light, the detection process further includes: adjusting the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer to adjust the light intensity of the second signal light.

15. The detection method according to claim 14, wherein, If the detection device further includes: a first rotating component, the first rotating component being connected to the second polarizer, or the first rotating component being connected to both the first polarizer and the third polarizer; Adjusting the angle between the polarization direction of the second polarizer and the polarization direction of the first polarizer includes: controlling the first rotating component to drive the second polarizer to rotate around a first rotating axis, wherein the first rotating axis is not parallel to the polarization direction of the second polarizer; or, controlling the first rotating component to drive the third polarizer to rotate around a second rotating axis, while simultaneously driving the first polarizer to rotate synchronously around the second rotating axis to ensure that the polarization direction of the first polarizer is perpendicular to the polarization direction of the third polarizer, wherein the second rotating axis is not parallel to the polarization direction of the first polarizer. And / or, if the detection device further includes a second rotating component connected to the third polarizer, or, the second rotating component is connected to both the second polarizer and the fourth polarizer; Adjusting the angle between the polarization direction of the third polarizer and the polarization direction of the fourth polarizer includes: controlling the second rotating component to drive the third polarizer to rotate around a third rotating axis, wherein the third rotating axis is not parallel to the polarization direction of the third polarizer; or, controlling the second rotating component to drive the second polarizer to rotate around a fourth rotating axis, while simultaneously driving the fourth polarizer to rotate synchronously around the fourth rotating axis to ensure that the polarization direction of the second polarizer is perpendicular to the polarization direction of the fourth polarizer, wherein the fourth rotating axis is not parallel to the polarization direction of the second polarizer.

16. The detection method according to claim 12, wherein, Detecting the object under test based on the signal light includes: acquiring detection images based on different signal lights received by the first detection component and the second detection component; and detecting and classifying the target under test based on each detection image, wherein the target under test includes defects.

17. The detection method according to claim 12 or 14, wherein, The detection device includes: a dark field light source assembly, the dark field light source assembly including at least one of a first dark field light source and a second dark field light source; the first dark field light source provides a first dark field light to the object under test, the first dark field light being scattered by the first surface of the object under test to form a first dark field signal light, the second dark field light source providing a second dark field light to the object under test, the second dark field light being scattered by the second surface of the object under test to form a second dark field signal light; the detection process further includes: receiving the first dark field signal light through the first detection component, receiving the second dark field signal light through the second detection component, the signal light further including one or a combination of the first dark field signal light and the second dark field signal light.

18. The detection method according to claim 17, wherein, The detection method further includes: controlling the dark field light source assembly to perform the detection process on the test object multiple times, and rotating the test object relative to the dark field light source assembly by a preset angle between adjacent detection processes; the dark field light source assembly includes one or a combination of the first dark field light source and the second dark field light source; the first dark field light source is a bar light source, and / or the second dark field light source is a bar light source.

19. The detection method according to claim 17, wherein, Before detecting the object under test based on the signal light, the method includes: controlling each light source to flash sequentially, and controlling the first detection component and the second detection component to simultaneously collect the signal light at a preset frequency; the preset frequency is greater than or equal to the flashing frequency of each light source, and each light source includes one or a combination of the first light source and the dark field light source component.

20. The detection method according to claim 19, wherein, Controlling each light source to blink sequentially includes: controlling the first dark field light source and the second dark field light source to blink simultaneously, and controlling the first detection component and the second detection component to simultaneously collect the signal light at the preset frequency; the preset frequency is greater than or equal to the blinking frequency of the first dark field light source and the second dark field light source.

Images