CN112200798B - Printed circuit board detection method based on X-ray layering technology - Google Patents
Printed circuit board detection method based on X-ray layering technology Download PDFInfo
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- CN112200798B CN112200798B CN202011181549.7A CN202011181549A CN112200798B CN 112200798 B CN112200798 B CN 112200798B CN 202011181549 A CN202011181549 A CN 202011181549A CN 112200798 B CN112200798 B CN 112200798B
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- 238000005516 engineering process Methods 0.000 title claims abstract description 12
- 238000001514 detection method Methods 0.000 title abstract description 15
- 230000033001 locomotion Effects 0.000 claims abstract description 23
- 238000000034 method Methods 0.000 claims abstract description 15
- 239000002131 composite material Substances 0.000 claims abstract description 13
- 238000013519 translation Methods 0.000 claims abstract description 12
- 238000012360 testing method Methods 0.000 claims description 8
- 238000007689 inspection Methods 0.000 abstract description 8
- 230000009286 beneficial effect Effects 0.000 abstract description 5
- 238000003325 tomography Methods 0.000 abstract description 3
- 230000007547 defect Effects 0.000 description 8
- 230000000694 effects Effects 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 3
- 238000002591 computed tomography Methods 0.000 description 3
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- 230000003287 optical effect Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
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- 230000001360 synchronised effect Effects 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T7/00—Image analysis
- G06T7/0002—Inspection of images, e.g. flaw detection
- G06T7/0004—Industrial image inspection
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F18/00—Pattern recognition
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- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T11/00—2D [Two Dimensional] image generation
- G06T11/003—Reconstruction from projections, e.g. tomography
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T2207/00—Indexing scheme for image analysis or image enhancement
- G06T2207/10—Image acquisition modality
- G06T2207/10072—Tomographic images
- G06T2207/10081—Computed x-ray tomography [CT]
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T2207/00—Indexing scheme for image analysis or image enhancement
- G06T2207/30—Subject of image; Context of image processing
- G06T2207/30108—Industrial image inspection
- G06T2207/30141—Printed circuit board [PCB]
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T2207/00—Indexing scheme for image analysis or image enhancement
- G06T2207/30—Subject of image; Context of image processing
- G06T2207/30168—Image quality inspection
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Abstract
The invention discloses a printed circuit board detection method based on an X-ray layering technology, which comprises the following steps of: s1, determining system parameters; s2, judging whether the motion type in the system parameter is a translation type or a rotation type; s3, if the motion type in the system parameters is a translation type, improving the picture quality by specifying the wire direction; s4, if the motion type in the system parameters is a rotation type, improving the picture quality by increasing the number of the synthesized images; s5, taking the correlation number CC as an index of image similarity, the printed circuit board detection method based on the X-ray layering technology has the following beneficial effects: the aim of the study is to optimize the X-ray tomography technique for printed circuit board detection, the system parameters studied including the type of motion, the number of composite images and the projection angle of the X-ray source, the correlation coefficient as an inspection index.
Description
Technical Field
The invention relates to the technical field of detection equipment, in particular to a printed circuit board detection method based on an X-ray layering technology.
Background
For printed circuit boards, visual inspection is often employed to detect board substrate damage, component loss, misplacement or damage, solder failure, and similar macroscopic quality defects. Automated optical inspection systems are being developed to automatically perform these inspections in an increasing number of devices. These automatic optical inspection systems can then only detect defects that occur on the surface of the inspected object, and they become useless for internal defects or defects that are hidden behind other objects. The use of X-ray images provides a means to solve this problem, and conventional transmission X-ray images generally provide clues to defects, and to provide more reliable and accurate defect information, X-ray computed tomography can be used to detect internal defects and provide reconstructed three-dimensional images, but X-ray computed tomography takes more processing time than conventional transmission X-ray inspection, and even if a single image is reconstructed for a certain plane, typically hundreds of images are required to reconstruct a good result. Tomosynthesis is another method of displaying images on specific slices in an assembly, which requires less time to process than X-ray computed tomography and provides more information than conventional transmission X-ray detection by using synchronized motion X-rays and detectors, while the imaged object remains stationary, the images are continuously collected throughout the movement, all the resulting images are averaged into a final image, which makes the object features in the focal plane more prominent in the final image, and the object features not in the focal plane are blurred, so these features only appear weak. The three-dimensional layout of the layered circuit can be generally understood by looking at a series of layered diagrams of adjacent planes.
Therefore, it is necessary to optimize the lamination method for printed circuit board inspection.
Disclosure of Invention
The invention provides a printed circuit board detection method based on an X-ray layering technology, which aims at solving the problems in the background technology.
The invention provides a printed circuit board detection method based on an X-ray layering technology, which comprises the following steps of:
s1, determining system parameters, wherein the system parameters comprise a motion type, the number of composite images and a projection angle of the X-ray in the direction of a lead, and the motion type, the number of composite images and the projection angle of the X-ray in the direction of the lead influence the quality of a reconstructed image on a focal plane;
s2, judging whether the motion type in the system parameter is a translation type or a rotation type;
s3, if the motion type in the system parameters is a translation type, improving the picture quality by specifying the wire direction;
s4, if the motion type in the system parameters is a rotation type, improving the picture quality by increasing the number of the synthesized images;
s5, taking the correlation coefficient CC as an index of image similarity, wherein the English name of the correlation coefficient CC is Correlation Coefficient, and the correlation coefficient CC is used for evaluating the similarity of the reference image and the reconstructed image.
A further improvement is that the number of composite images refers to the number of images collected when reconstructing images at the focal plane, with test levels of 4, 8, 16 and 32 images.
A further improvement is that the projection angle refers to the angle between the direction from the X-ray source to the centre point of the object surface and the normal direction to the surface plane, the test levels being 45 °, 54 ° and 63 °.
The further improvement is that the step S5 specifically includes:
the correlation coefficient CC is determined using the following equation:
where m and n are the width and height, respectively, of an image pixel, the image pixel being an integer, f s (x, y) and f T (x, y) is the gray level, μ, of the reference image and the reconstructed image, respectively, at a given image position (x, y) s Sum mu T Is the gray average of the reference image and the reconstructed image;and->The grayscale variance of the reference image and the reconstructed image, respectively.
Compared with the prior art, the invention has the beneficial effects that:
the printed circuit board detection method based on the X-ray layering technology has the beneficial effects that: the aim of the study is to optimize the X-ray tomography technique for printed circuit board detection, the system parameters studied including the type of motion, the number of composite images and the projection angle of the X-ray source, the correlation coefficient as an inspection index. From the experimental results, the following conclusions can be drawn:
1. when a translation mode is adopted, the translation direction of the x-ray source should not be parallel to the main line direction on the non-focal plane. Thus, in order to achieve a satisfactory effect when using a translational type, the direction of the main line should be provided. It has also been found that the quality of the reconstructed image generally improves as the number of composite images increases.
2. When the rotation type is adopted, the increase in the number of synthesized images also improves the quality of the reconstructed image. However, when the number of synthesized images is greater than 16, the improvement effect is not obvious, and in this test, the correlation coefficient difference between the image reconstructed from 32 frames and the image reconstructed from only 16 frames is less than 1%. It has also been found that the difference in correlation coefficient between the uppermost and lowermost layers is also greatly reduced.
Drawings
The drawings are for illustrative purposes only and are not to be construed as limiting the present patent; for the purpose of better illustrating the embodiments, certain elements of the drawings may be omitted, enlarged or reduced and do not represent the actual product dimensions; it will be appreciated by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
Fig. 1 is a schematic overall flow chart of an embodiment of the present invention.
Detailed Description
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted", "connected" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected or integrally connected; can be mechanically or electrically connected; the two elements may be directly connected or indirectly connected through an intermediate medium, so to speak, the two elements are communicated internally. It will be understood by those of ordinary skill in the art that the terms described above are in the specific sense of the present invention. The technical scheme of the invention is further described below with reference to the accompanying drawings and examples.
The invention provides a method for detecting defects of a printed circuit board based on an X-ray layering technology, aiming at researching the influence of certain system parameters on reconstruction quality, wherein the researched system parameters comprise a kinematic type system, the number of synthesized images and a projection angle. Simulation results indicate that with the translational type, the translational direction of the X-ray source should not be parallel to the wire direction on the other plane, in other words, when the translational type is used, the wire direction has to be specified to produce good results. When the rotation type is adopted, the influence of the wire direction on the reconstructed image is small, and the image quality is generally improved by increasing the number of synthesized images, but when the number of images is increased, the meaning of improvement is not great. For example, for the case of detection, the difference in the images reconstructed from 32 frames and 16 frames is less than 1%.
Referring to fig. 1, a method for inspecting a printed circuit board based on an X-ray layering technique includes the steps of:
s1, determining system parameters, wherein the system parameters comprise a motion type, the number of composite images and a projection angle of the X-ray in the direction of a lead, and the motion type, the number of composite images and the projection angle of the X-ray in the direction of the lead influence the quality of a reconstructed image on a focal plane; two kinematic types studied are translational and rotational types, rotational types may have a more compact system design than translational types, however, it is interesting to study which type can produce better image quality;
s2, judging whether the motion type in the system parameter is a translation type or a rotation type;
s3, if the motion type in the system parameters is a translation type, improving the picture quality by specifying the wire direction;
s4, if the motion type in the system parameters is a rotation type, improving the picture quality by increasing the number of the synthesized images;
s5, taking the correlation coefficient CC as an index of image similarity, wherein the English name of the correlation coefficient CC is Correlation Coefficient, and the correlation coefficient CC is used for evaluating the similarity of the reference image and the reconstructed image.
As a preferred embodiment of the present invention, the number of the composite images refers to the number of images collected when reconstructing the images in the focal plane, and the more images are expected to be photographed, the better the image effect can be obtained. However, the processing time increases. Thus, the test levels are 4, 8, 16 and 32 images.
As a preferred embodiment of the invention, the projection angle refers to the angle between the direction from the X-ray source to the center point of the object surface and the normal direction to the surface plane, and it is generally considered that smaller angles may reduce the size of the system. For a translational machine, the projection angle is not a constant, and therefore, the test orders are 45 °, 54 °, and 63 ° with the maximum projection angle as an index.
As a preferred embodiment of the present invention, the step S5 specifically includes:
the correlation coefficient CC is determined using the following equation:
where m and n are the width and height, respectively, of an image pixel, the image pixel being an integer, f s (x, y) and f T (x, y) is the gray level, μ, of the reference image and the reconstructed image, respectively, at a given image position (x, y) s Sum mu T Is the gray average of the reference image and the reconstructed image;and->The grayscale variance of the reference image and the reconstructed image, respectively.
Compared with the prior art, the invention has the beneficial effects that:
the printed circuit board detection method based on the X-ray layering technology has the beneficial effects that: the aim of the study is to optimize the X-ray tomography technique for printed circuit board detection, the system parameters studied including the type of motion, the number of composite images and the projection angle of the X-ray source, the correlation coefficient as an inspection index. From the experimental results, the following conclusions can be drawn:
1. when a translation mode is adopted, the translation direction of the x-ray source should not be parallel to the main line direction on the non-focal plane. Thus, in order to achieve a satisfactory effect when using a translational type, the direction of the main line should be provided. It has also been found that the quality of the reconstructed image generally improves as the number of composite images increases.
2. When the rotation type is adopted, the increase in the number of synthesized images also improves the quality of the reconstructed image. However, when the number of synthesized images is greater than 16, the improvement effect is not obvious, and in this test, the correlation coefficient difference between the image reconstructed from 32 frames and the image reconstructed from only 16 frames is less than 1%. It has also been found that the difference in correlation coefficient between the uppermost and lowermost layers is also greatly reduced.
In the drawings, the positional relationship is described for illustrative purposes only and is not to be construed as limiting the present patent; it is to be understood that the above examples of the present invention are provided by way of illustration only and not by way of limitation of the embodiments of the present invention. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are desired to be protected by the following claims.
Claims (4)
1. The method for detecting the printed circuit board based on the X-ray layering technology is characterized by comprising the following steps of:
s1, determining system parameters, wherein the system parameters comprise a motion type, the number of composite images and a projection angle of the X-ray in the direction of a lead, and the motion type, the number of composite images and the projection angle of the X-ray in the direction of the lead influence the quality of a reconstructed image on a focal plane;
s2, judging whether the motion type in the system parameter is a translation type or a rotation type;
s3, if the motion type in the system parameters is a translation type, improving the picture quality by specifying the wire direction;
s4, if the motion type in the system parameters is a rotation type, improving the picture quality by increasing the number of the synthesized images;
s5, taking the correlation coefficient CC as an index of image similarity, wherein the English name of the correlation coefficient CC is Correlation Coefficient, and the correlation coefficient CC is used for evaluating the similarity of the reference image and the reconstructed image.
2. The method for inspecting a printed circuit board based on an X-ray layering technique according to claim 1, wherein the number of the synthesized images is the number of images collected when reconstructing the images at the focal plane, and the test level is 4, 8, 16 and 32 images.
3. The method according to claim 1, wherein the projection angle is an angle between a direction from the X-ray source to a center point of the object surface and a normal direction of the surface plane, and the test level is 45 °, 54 ° and 63 °.
4. The method for inspecting a printed circuit board based on the X-ray layering technique according to claim 1, wherein the step S5 specifically comprises:
the correlation coefficient CC is determined using the following equation:
where m and n are the width and height, respectively, of an image pixel, the image pixel being an integer, f s (x, y) and f T (x, y) is the gray level, μ, of the reference image and the reconstructed image, respectively, at a given image position (x, y) s Sum mu T Is the gray average of the reference image and the reconstructed image;and->The grayscale variance of the reference image and the reconstructed image, respectively.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101706458A (en) * | 2009-11-30 | 2010-05-12 | 中北大学 | Automatic detection system and detection method of high resolution printed circuit board |
| CN101839871A (en) * | 2010-05-18 | 2010-09-22 | 华南理工大学 | X-ray layered photography detection method and system |
| DE602004028588D1 (en) * | 2003-03-14 | 2010-09-23 | Philips Intellectual Property | MOTION CORRECTED THREE-DIMENSIONAL VOLUME IMAGING PROCESS |
| CN103278515A (en) * | 2013-05-16 | 2013-09-04 | 华南理工大学 | Rotary X-ray layered photographic detection system and method |
| WO2014181889A1 (en) * | 2013-05-10 | 2014-11-13 | 株式会社テレシステムズ | Substance identification device and substance identification method employing x-ray panoramic/ct photographing |
| CN106897994A (en) * | 2017-01-20 | 2017-06-27 | 北京京仪仪器仪表研究总院有限公司 | A kind of pcb board defect detecting system and method based on layered image |
| EP3725227A1 (en) * | 2019-04-18 | 2020-10-21 | DENTSPLY SIRONA Inc. | Method of calibrating x-ray projection geometry in x-ray cone beam computed tomography |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7489760B2 (en) * | 2005-07-27 | 2009-02-10 | Sectra Mamea Ab | Method and arrangement relating to X-ray imaging |
-
2020
- 2020-10-29 CN CN202011181549.7A patent/CN112200798B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE602004028588D1 (en) * | 2003-03-14 | 2010-09-23 | Philips Intellectual Property | MOTION CORRECTED THREE-DIMENSIONAL VOLUME IMAGING PROCESS |
| CN101706458A (en) * | 2009-11-30 | 2010-05-12 | 中北大学 | Automatic detection system and detection method of high resolution printed circuit board |
| CN101839871A (en) * | 2010-05-18 | 2010-09-22 | 华南理工大学 | X-ray layered photography detection method and system |
| WO2014181889A1 (en) * | 2013-05-10 | 2014-11-13 | 株式会社テレシステムズ | Substance identification device and substance identification method employing x-ray panoramic/ct photographing |
| CN103278515A (en) * | 2013-05-16 | 2013-09-04 | 华南理工大学 | Rotary X-ray layered photographic detection system and method |
| CN106897994A (en) * | 2017-01-20 | 2017-06-27 | 北京京仪仪器仪表研究总院有限公司 | A kind of pcb board defect detecting system and method based on layered image |
| EP3725227A1 (en) * | 2019-04-18 | 2020-10-21 | DENTSPLY SIRONA Inc. | Method of calibrating x-ray projection geometry in x-ray cone beam computed tomography |
Non-Patent Citations (3)
| Title |
|---|
| 基于主动红外热成像的倒装焊缺陷检测方法研究;陆向宁;中国博士学位论文全文数据库（电子期刊）·工程科技Ⅰ辑(第8期);B022-34 * |
| 基于分层参考比对法印刷电路板自动检测技术;刘国忠;李运生;周玺;徐炜君;;制造业自动化(第11期);全文 * |
| 微焦点X射线分层成像无损检测方法;李政, 王, 程建平, 王学武, 倪建平, 康克军;无损检测(第05期);全文 * |
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