Detection device and detection method

Abstract

The present application discloses a detection device and a detection method, wherein the detection device includes a first detector and a second detector; the first field of view of the first detector covers the first area of ​​the surface of the object to be detected, and the first detector is used to image the first area and obtain an image of the first area; the second field of view of the second detector covers the second area of ​​the surface of the object to be detected, and the second detector is used to image the second area and obtain an image of the second area; the first area partially overlaps the second area; the overlapping part of the first area and the second area has a feature mark, the feature mark has a feature point, and the image of the feature mark does not have rotational symmetry about any point other than the feature point. The embodiment of the present application can be used to detect products with two different areas.

Description

Technical Field

[0001] The present application relates to the field of detection technology, and in particular to a detection device and a detection method. Background Art

[0002] Glass materials are widely used in modern industrial manufacturing, such as mobile phone screens, optical lenses, battery cells, curved display screens, etc. With the advancement of processing technology, more and more glass products are designed with curved structures to achieve better functions or better appearance. Since the curved surface is difficult to process, there is a greater possibility of defects on the curved surface, which will affect its function and appearance. Therefore, it is necessary to test products with curved structures. Summary of the invention

[0003] The embodiments of the present application provide a detection device and a detection method.

[0004] In a first aspect, the present application provides a detection device, comprising:

[0005] A first detector, wherein a first field of view of the first detector covers a first area on the surface of the object to be measured, and is used to image the first area and obtain an image of the first area;

[0006] A second detector, wherein a second field of view of the second detector covers a second area on the surface of the object to be measured, and is used to image the second area and obtain an image of the second area;

[0007] The first area partially overlaps with the second area;

[0008] The overlapping portion of the first area and the second area has a feature mark, the feature mark has a feature point, and the image of the feature mark has no rotational symmetry with respect to any point other than the feature point.

[0009] In one implementation, the detection device further includes a first light source, and the emitted light of the first light source covers the first area and the second area.

[0010] In one implementation, the characteristic mark is an additional mark sprayed or pasted on the surface of the object to be tested.

[0011] In one implementation, the color or material of the additional mark is different from that of the object to be detected.

[0012] In one implementation, the detection device further includes a second light source, and the characteristic identifier is a light spot formed on the overlapping portion by an outgoing light beam of the second light source.

[0013] In one implementation, the wavelength or brightness of the light emitted by the second light source is different from that of the light emitted by the first light source.

[0014] In one implementation, the first light source is a white light source; and the second light source is a colored visible light source.

[0015] In one implementation, the first light source is an LED light source, and the second light source is a laser light source.

[0016] In one implementation, the detector is a linear array detector or a planar array detector.

[0017] In one implementation, the depth of field of the second detector is greater than the length of a third region along the optical axis of the second detector, and the third region is a region limited by the feature mark and an edge of the second region.

[0018] In one implementation, a normal vector of at least one point in the second region is different from normal vectors of all points in the first region.

[0019] In one implementation, the first region is a plane, and the second region is a curved surface.

[0020] In one implementation, the number of the feature identifiers is one or more, and the sum of the number of feature points in all the feature identifiers is greater than or equal to 2.

[0021] It can be seen that in the embodiment of the present application, the detection device includes a first detector and a second detector. The first field of view of the first detector covers the first area of ​​the object to be detected, and the second field of view of the second detector covers the second area of ​​the object to be detected. The first area partially overlaps with the second area, thereby realizing the detection of products with two different areas and solving the detection problem that conventional detection devices cannot detect such products.

[0022] In a second aspect, the present application provides a detection method, which is applied to the detection device described in the first aspect, and the method comprises:

[0023] Imaging a first region on the surface of the object to be measured by a first detector to acquire a first image;

[0024] Imaging a second region of the surface of the object to be measured by a second detector to obtain a second image;

[0025] The first image and the second image are stitched together according to feature point images in the first image and the second image.

[0026] In one implementation, the step of performing image stitching on the first image and the second image according to feature point images in the first image and the second image includes:

[0027] Acquire a first feature point image of feature points in the first image;

[0028] Acquire a second feature point image of feature points in the second image;

[0029] Matching the first feature point image with the second feature point image to obtain matching feature points;

[0030] The first image and the second image are spliced ​​according to the matching feature points.

[0031] In one implementation, the second area includes a target area, a normal line of the target area and an optical axis of the second detector have an angle vector, and the second image includes a target image of the target area; before stitching the first image and the second image, the method further includes:

[0032] Performing image conversion on the target image based on the angle vector to obtain a conversion image, wherein the target image is a projection image of the conversion image in a projection plane, and the projection plane is a plane perpendicular to the optical axis of the second detector;

[0033] The target image is replaced by the conversion image.

[0034] In one implementation, the method further includes:

[0035] Dividing the target area into a plurality of sub-areas, the target image includes a plurality of sub-area images, the normal lines of the plurality of sub-areas respectively having angle vectors with the optical axis of the second detector, forming a plurality of angle vectors;

[0036] The performing image conversion on the target image based on the angle vector to obtain a conversion image includes: performing image conversion on the multiple sub-region images based on the multiple angle vectors to obtain multiple conversion images, wherein the multiple conversion images correspond to the multiple sub-region images one by one;

[0037] The replacing the target image with the conversion image comprises: replacing the multiple sub-region images respectively with the multiple conversion images.

[0038] In one implementation, the sub-region image of a single sub-region includes one or more pixels.

[0039] In one implementation, performing image conversion on the multiple sub-region images based on the multiple acute angles includes:

[0040] Determining relative positional relationships between the plurality of sub-region images and the reference point, wherein the determined plurality of relative positional relationships correspond one-to-one to the plurality of sub-region images;

[0041] Based on the multiple relative position relationships and the multiple angle vectors, image conversion is performed on the multiple sub-region images.

[0042] In one implementation, an overlapping image region of the first image and the second image includes the reference point.

[0043] It can be seen that in the embodiment of the present application, the first image acquired by the first detector and the second image acquired by the second detector are stitched to obtain a complete detection image of the object to be detected, so as to facilitate subsequent analysis of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 is a schematic diagram of the structure of a detection device provided by an embodiment of the present application;

[0046] Figure 2 is a schematic diagram of the length of the target area along the optical axis direction of the second detector provided by an embodiment of the present application;

[0047] Figure 3 is a flowchart of an image stitching method provided by an embodiment of the present application;

[0048] Figure 4 It is a schematic diagram of image stitching provided by an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

[0050] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of a detection device provided in one embodiment of the present application. Figure 1 As shown, the detection device includes a first detector 10 and a second detector 20;

[0051] The first field of view of the first detector 10 covers a first area on the surface of the object to be measured, and the first detector 10 is used to image the first area and obtain an image of the first area;

[0052] The second field of view of the second detector 20 covers a second area on the surface of the object to be measured, and the second detector 20 is used to image the second area and obtain an image of the second area;

[0053] The first area partially overlaps with the second area, and the overlapping portion of the first area and the second area has a feature identifier, the feature identifier has a feature point, and the image of the feature identifier has no rotational symmetry about any point other than the feature point.

[0054] In this embodiment, the detection device further includes a stage 30, and the stage 30 is used to carry the object to be tested. The object to be tested may be, for example, an optical lens, a battery cell, a curved display screen, and the like.

[0055] The number of the feature identifiers is one or more, and the sum of the number of feature points in all the feature identifiers is greater than or equal to 2. Specifically, in this embodiment, the sum of the number of the feature identifiers is greater than or equal to 4.

[0056] Optionally, the first region is a plane and the second region is a curved surface. The second region may be spherical, cylindrical, or other shapes. The number of the second regions is one or more.

[0057] Optionally, the number of overlapping parts between the first region and the second region is one or more. When the number of overlapping parts between the first region and the second region is multiple, different overlapping parts have different characteristic identifiers.

[0058] Optionally, the detector is a linear array detector or a planar array detector. The number of the second detectors 20 is one or more. The first detector 10 and the second detector 20 can work simultaneously, or the first detector 10 and the second detector 20 can work at different times. The first detector 10 and the second detector 20 are calibrated in their relative position.

[0059] It should be noted that in Figure 1 In the embodiment, the first detector 10 is disposed on an upper surface away from the first area, and the second detector 20 is disposed on an upper surface away from the second area. Figure 1 The structure of the detection device shown is only for illustration. The detection device provided in this application is not limited to Figure 1 The structure shown.

[0060] It can be seen that in the embodiment of the present application, the first image acquired by the first detector and the second image acquired by the second detector are stitched to obtain a complete detection image of the object to be detected, so as to facilitate subsequent analysis of the product.

[0061] In one implementation, the detection device further includes at least one first light source, and the emitted light of the first light source covers the first area and the second area.

[0062] The first light source is an LED light source. Specifically, in this embodiment, the number of the first light source is one, and the first light source is a strip LED light source. The first light source is used to emit detection light to the first area and the second area respectively; the first light source forms bright field illumination or dark field illumination relative to the first detector; the second light source forms bright field illumination or dark field illumination relative to the second detector.

[0063] In another embodiment, the number of the first light sources is multiple, and the multiple first light sources emit detection light to the first area and the second area respectively. Specifically, the first light source is an annular light source or a coaxial light source; when the first light source is an annular light source, the annular light source has a through hole, and the detector collects the detection light returned by the object to be tested through the through hole; when the first light source is a coaxial light source, the coaxial light source includes a beam splitter and a light emitter, the light emitter is used to emit initial light, the light splitter is located between the detector and the object to be tested, and the beam splitter is used to reflect the initial light to the surface of the object to be tested, and allow the detection light reflected by the object to be tested to pass through and be received by the detector.

[0064] It should be noted that the present application does not limit the location of the first light source, as long as the emitted light of the first light source can cover the first area and the second area.

[0065] In one implementation, the characteristic mark is an additional mark sprayed or pasted on the surface of the object to be tested.

[0066] Optionally, the color or material of the additional mark is different from that of the object to be detected. The detection light emitted by the first light source is visible light. The first detector is a color detector, and the second detector is a color detector.

[0067] In one implementation, the detection device further includes a second light source, and the characteristic identifier is a light spot formed on the overlapping portion by an outgoing light beam of the second light source.

[0068] The number of the second light sources is one or more. The second light source is a laser light source, and the color of the light emitted by the laser light source can be green, red, blue, etc. The first light source is a white light source.

[0069] It should be noted that the present application does not limit the location of the second light source, as long as the emitted light from the second light source can form a light spot on the overlapping portion of the first area and the second area.

[0070] In one implementation, the wavelength or brightness of the light emitted by the second light source is different from that of the light emitted by the first light source.

[0071] In one implementation, the depth of field of the second detector 20 is greater than the length of the third region along the optical axis direction of the second detector 20 , and the third region is a region limited by the feature marker and the edge of the second region.

[0072] like Figure 2 As shown, h is the length of the third area along the optical axis direction of the second detector 20. In order for the second detector 20 to capture a clear image of the second area, the maximum depth of field of the second detector 20 needs to be greater than h.

[0073] In this embodiment, the normal vector of at least one point of the second region is different from the normal vectors of all points of the first region. Specifically, the second region is a curved surface or the first region and the second region are both planes, and there is a non-zero angle between the first region and the second region.

[0074] When the second area is a curved area, the second detector 20 matches the contour of the curved area. Specifically, the field of view of the second detector 20 matches the contour of the curved area, and / or the angle between the optical axis of the second detector 20 and the horizontal plane matches the contour of the curved area.

[0075] In one implementation, the detection device further includes a controller, which is electrically connected to the first detector 10 and the second detector 20 .

[0076] It should be noted that the setting position of the controller is not limited in this application, as long as it does not affect the detection effect of the first detector 10 and the second detector 20 and can be electrically connected to the first detector 10 and the second detector 20.

[0077] See also Figure 3 , Figure 3 is a schematic diagram of the structure of a detection method provided by an embodiment of the present application, which is applied to the above-mentioned detection device, such as Figure 3 As shown, the detection method comprises the following steps:

[0078] Step 301: imaging a first region on the surface of an object to be measured by a first detector to obtain a first image.

[0079] Step 302: imaging a second region on the surface of the object to be measured by a second detector to obtain a second image.

[0080] Step 303: performing image stitching on the first image and the second image according to the feature point images in the first image and the second image.

[0081] Since the number of the second detectors is one or more, the number of the second images is one or more.

[0082] Optionally, the performing image stitching on the first image and the second image according to feature point images in the first image and the second image includes:

[0083] Acquire a first feature point image of feature points in the first image;

[0084] Acquire a second feature point image of feature points in the second image;

[0085] Matching the first feature point image with the second feature point image to obtain matching feature points;

[0086] The first image and the second image are spliced ​​according to the matching feature points.

[0087] The number of the matching feature points is 1 or more. The feature identifiers include matching feature points.

[0088] Optionally, after stitching the first image and the second image, the method further includes: removing the matching feature points from the stitched image.

[0089] Specifically, since a feature mark is provided on the surface of the object to be tested and the feature mark is located in the overlapping portion, the first feature point image and the second feature point image both include the image of the feature mark, and the detection device can quickly and accurately perform image stitching through the feature points included in the feature mark. Figure 4 As shown, the feature identifiers are A and B, and the first image and the second image can be spliced ​​through the feature points included in the feature identifiers A and B.

[0090] It can be seen that in the embodiment of the present application, the first image acquired by the first detector and the second image acquired by the second detector are stitched to obtain a complete detection image of the object to be detected, so as to facilitate subsequent analysis of the product.

[0091] In one implementation, the second area includes a target area, a normal line of the target area and an optical axis of the second detector have an angle vector, and the second image includes a target image of the target area; before stitching the first image and the second image, the method further includes:

[0092] Performing image conversion on the target image based on the angle vector to obtain a conversion image, wherein the target image is a projection image of the conversion image in a projection plane, and the projection plane is a plane perpendicular to the optical axis of the second detector;

[0093] The target image is replaced by the conversion image.

[0094] Specifically, since the second image is an image obtained by the second detector capturing the curved surface area along the optical axis, the second image will compress the size of the actual curved surface area. Therefore, the second image needs to be converted before image stitching to obtain an accurate and complete detection image of the object to be tested, so as to improve the detection accuracy.

[0095] In one implementation, the method further includes:

[0096] Dividing the target area into a plurality of sub-areas, the target image includes a plurality of sub-area images, the normal lines of the plurality of sub-areas respectively have angle vectors with the optical axis of the second detector, forming a plurality of angle vectors, and the plurality of sub-areas correspond to the plurality of angle vectors one by one;

[0097] The performing image conversion on the target image based on the angle vector to obtain a conversion image includes: performing image conversion on the multiple sub-region images based on the multiple angle vectors to obtain multiple conversion images, wherein the multiple conversion images correspond to the multiple sub-region images one by one;

[0098] The replacing the target image with the conversion image comprises: replacing the multiple sub-region images respectively with the multiple conversion images.

[0099] Optionally, the sub-region image of a single sub-region includes one or more pixels.

[0100] In one implementation, performing image conversion on the multiple sub-region images based on the multiple acute angles includes:

[0101] Determine the relative positional relationship between the plurality of sub-region images and the reference point, wherein the determined plurality of offsets correspond one-to-one to the plurality of sub-region images;

[0102] Based on the multiple relative position relationships and the multiple angle vectors, image conversion is performed on the multiple sub-region images.

[0103] Optionally, the overlapping image area of ​​the first image and the second image includes the reference point. That is, the reference point is one of the feature points that match the first image and the second image, that is, the matching feature point includes the reference point.

[0104] Optionally, the position of the reference point in the second image is the same as that in the converted image. That is, if the coordinates of the reference point in the second image are (a1, b1), then the coordinates of the reference point in the converted image are also (a1, b1).

[0105] Optionally, determining the relative positional relationship between the multiple sub-region images and the reference point includes: determining the relative positional relationship between a pixel point included in each of the sub-region images and the reference point.

[0106] The pixel point included in the sub-region image may be any pixel point included in the sub-region image, or may be a central pixel point included in the sub-region image.

[0107] Optionally, performing image conversion on the multiple sub-region images based on the multiple relative position relationships and the multiple angle vectors includes:

[0108] Based on the relative position relationship and the angle vector corresponding to each of the sub-region images, determine the target relative position relationship corresponding to each of the sub-region images, wherein the target relative position relationship is used to represent the relative position relationship between the conversion image corresponding to the sub-region image and the reference point;

[0109] Based on the relative position relationship of the target corresponding to each of the sub-region images and the position of the reference point, determine the position of the conversion image corresponding to each of the sub-region images to obtain a plurality of conversion positions, wherein the plurality of conversion positions correspond to the plurality of sub-region images one by one;

[0110] The plurality of sub-region images are image-converted based on the plurality of conversion positions.

[0111] Among them, the target relative position relationship is used to represent the relative position relationship between the conversion image corresponding to the sub-region image and the reference point, including: the target offset is used to represent the relative position relationship between a pixel point included in the conversion image corresponding to the sub-region image and the reference point.

[0112] The pixel point included in the conversion image may be any pixel point included in the conversion image, or may be a central pixel point included in the conversion image.

[0113] Optionally, determining the target relative position relationship corresponding to each of the sub-region images based on the relative position relationship and the angle vector corresponding to each of the sub-region images includes:

[0114] Determine the relative position relationship of the target corresponding to each of the sub-region images based on the calculation formula, the relative position relationship corresponding to each of the sub-region images and the angle vector

[0115] The calculation formula is: X=Y / cosα, X is the relative position relationship to be calculated, Y is the known relative position relationship, and α is the angle vector.

[0116] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. It can be understood by those skilled in the art that the detection device of the present application is not only applicable to the detection of products with curved surface structures, but also applicable to the detection of other items. Therefore, any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A detection device, characterized in that: include: A first detector, wherein a first field of view of the first detector covers a first area on the surface of the object to be measured, and is used to image the first area and obtain an image of the first area, wherein the first area is a plane; a second detector, wherein a second field of view of the second detector covers a second area of ​​the surface of the object to be measured, and is used to image the second area and obtain an image of the second area, the second area is a curved surface, and the second detector matches the contour of the curved surface; a first light source, wherein the emitted light of the first light source covers the first area and the second area, the first light source is an annular light source or a coaxial light source, the annular light source has a through hole, the coaxial light source includes a beam splitter and a light emitter, and the first light source forms bright field illumination or dark field illumination relative to the first detector; in, The first area partially overlaps with the second area; The overlapping part of the first area and the second area has a feature identifier, and the feature identifier has a feature point, so that the image of the first area and the image of the second area are stitched based on the feature point, and the image of the feature identifier has no rotational symmetry about any point other than the feature point.

2. The detection device according to claim 1, characterized in that: The characteristic mark is an additional mark sprayed or pasted on the surface of the object to be tested.

3. The detection device according to claim 2, characterized in that: The color or material of the additional mark is different from that of the object to be detected.

4. The detection device according to claim 1, characterized in that: The detection device further includes a second light source, and the characteristic identifier is a light spot formed on the overlapping portion by the outgoing light of the second light source.

5. The detection device according to claim 4, characterized in that: The wavelength or brightness of the light emitted by the second light source is different from that of the light emitted by the first light source.

6. The detection device according to claim 5, characterized in that: The first light source is a white light source; the second light source is a colored visible light source.

7. The detection device according to claim 5, characterized in that: The first light source is an LED light source, and the second light source is a laser light source.

8. The detection device according to any one of claims 1 to 7, characterized in that: The detector is a linear array detector or a planar array detector.

9. The detection device according to any one of claims 1 to 7, characterized in that: The normal vector of at least one point in the second region is different from the normal vectors of all points in the first region.

10. The detection device according to any one of claims 1 to 7, characterized in that: The number of the feature identifiers is one or more, and the total number of feature points in all the feature identifiers is greater than or equal to 2.

11. A detection method, characterized in that: Based on the detection device according to any one of claims 1 to 10, the method comprises: Imaging a first region on the surface of the object to be measured by a first detector to acquire a first image; A second area on the surface of the object to be measured is imaged by a second detector to obtain a second image; and the first image and the second image are image stitched according to feature point images in the first image and the second image.

12. The detection method according to claim 11, characterized in that: The step of performing image stitching on the first image and the second image according to the feature point images in the first image and the second image comprises: Acquire a first feature point image of feature points in the first image; Acquire a second feature point image of feature points in the second image; Matching the first feature point image with the second feature point image to obtain matching feature points; The first image and the second image are spliced ​​according to the matching feature points.

13. The method according to claim 11 or 12, characterized in that: The second area includes a target area, a normal line of the target area and an optical axis of the second detector have an angle vector, and the second image includes a target image of the target area; before stitching the first image and the second image, the method further includes: Performing image conversion on the target image based on the angle vector to obtain a conversion image, wherein the conversion image is a projection image of the target image in a projection plane, and the projection plane is a plane perpendicular to the optical axis of the second detector; The target image is replaced by the conversion image.

14. The method according to claim 13, characterized in that The method further comprises: Dividing the target area into a plurality of sub-areas, the target image includes a plurality of sub-area images, the normal lines of the plurality of sub-areas respectively having angle vectors with the optical axis of the second detector, forming a plurality of angle vectors; The performing image conversion on the target image based on the angle vector to obtain a conversion image includes: performing image conversion on the multiple sub-region images based on the multiple angle vectors to obtain multiple conversion images, wherein the multiple conversion images correspond to the multiple sub-region images one by one; The replacing the target image with the conversion image comprises: replacing the multiple sub-region images respectively with the multiple conversion images.

15. The method according to claim 14, characterized in that The sub-region image of a single sub-region includes one or more pixels.

16. The method according to claim 14 or 15, characterized in that The performing image conversion on the multiple sub-region images based on the multiple angle vectors includes: Determining relative positional relationships between the plurality of sub-region images and the reference point, wherein the determined plurality of relative positional relationships correspond one-to-one to the plurality of sub-region images; Based on the multiple relative position relationships and the multiple angle vectors, image conversion is performed on the multiple sub-region images.

17. The method according to claim 16, characterized in that An overlapping image area of ​​the first image and the second image includes the reference point.

Images