JP2009036736A - Printed soft solder inspection method and device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed soft solder inspection method and device which can exactly detect a state of a printed soft solder. <P>SOLUTION: The device comprises optical systems 20, 30 which picturize a two-dimensional image of the soft solder 10x printed on a substrate 10, and also the optical systems 20, 30 which images a three-dimensional image of the printed soft solder. The device processes the two-dimensional image and the three-dimensional image and measures items 61 of the two dimensional shape, like a bottom planar area, a pad area or the like of the printed soft solder, and measures the items 62 of the three-dimensional shape like a cross section, a projection area, the mean height, a peak height, a volume, or the like. Furthermore, the printed soft solder shape is determined, based on these items. Additionally, the device comprises the inspection parts 50, 60 and 80 which determine formation success or failure of the printed soft solder combining at least these two measuring items in a matrix form. By this procedure, the determination becomes possible on the shape of the printed soft solder correctly; and it becomes possible to judge formation success or failure of the printed soft solder exactly, rather than carrying out the two dimensional measurement and the three dimensional measurement independently, respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an inspection method and apparatus for solder printed on a substrate, and more particularly to a printed solder inspection method and apparatus for inspecting based on a two-dimensional measurement result and a three-dimensional measurement result of the printed solder.

  The printed solder is a process of transferring paste-like cream solder onto a pad of a substrate through an opening provided in a thin metal plate called a metal mask. Therefore, cream solder (printed solder) printed on a substrate usually has a thickness of about 100 μm to 150 μm. Of course, a three-dimensional measurement technique is necessary to grasp the transfer situation in the thickness direction.

  In the three-dimensional measurement in the printed solder inspection method, it is ideal if the upper surface of the pad to which the printed solder is transferred is set as a height measurement reference surface and the height or volume of the printed solder protruding therefrom can be measured. However, since the pad is covered with printed solder on the printed board, the upper surface of the pad cannot be detected as the height measurement reference plane. Therefore, the upper surface of the resist other than the pad is generally used as a height measurement reference surface, but the upper surface of the resist is generally higher than the upper surface of the pad. It cannot be measured.

  Even if the height measurement reference plane is the same as the height of the pad upper surface, if the reference plane is set to the lower side, the volume of the printed circuit board under the solder will be measured. , The measurement result will be greatly different from the substance. Therefore, in the three-dimensional measurement in the printed solder inspection method, it is common to set the height measurement reference plane upward by about 20 μm to 30 μm so that the accuracy limit does not greatly affect the measurement result. (See Patent Document 1).

Japanese Patent Laid-Open No. 2005-207918

  In the printed solder inspection method based on three-dimensional measurement, for the above two reasons, for example, a problem called “bleeding” in which the printed solder spreads thinly cannot be detected.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a printed solder inspection method and apparatus capable of accurately inspecting the state of printed solder.

  In order to achieve the above object, in the printed solder inspection method of the present invention, the two-dimensional measurement and three-dimensional measurement of the solder printed on the substrate, the two-dimensional measurement result and the three-dimensional measurement result are used. And a step of determining the shape of the printed solder. As a result, the shape of the printed solder can be determined more accurately than when two-dimensional measurement and three-dimensional measurement are performed separately.

  In order to achieve the above object, another printed solder inspection method of the present invention uses a step of performing two-dimensional measurement and three-dimensional measurement of solder printed on a board, and uses the two-dimensional measurement result and the three-dimensional measurement result. And a step of determining whether or not the printed solder is formed.

  Some of the conventional printed solder inspection methods also mention the combined use of two-dimensional measurement and three-dimensional measurement, but the content is measured in two dimensions and inspected the entire surface of the board, and only the necessary parts are three-dimensional. It is to measure and inspect. The purpose and purpose is to measure and inspect the entire surface of the substrate in three dimensions, but it is not realistic in terms of measurement speed. Therefore, the entire surface of the substrate is measured and inspected in two dimensions at high speed. The proposal was unavoidable passive sharing, in which only the part for which quality assurance was desired was measured and inspected in three dimensions.

  However, in the printed solder inspection method of the present invention, the two-dimensional measurement and the three-dimensional measurement complement each other, and by using both of them, it is possible to accurately determine whether the printed solder is formed or not. For example, the bottom area of the printed solder effective for blur detection etc. is measured using two-dimensional measurement, and the printed solder effective for blur detection etc. using three-dimensional measurement (part protruding upward from the height measurement reference plane) ) Is measured in two steps, and the quality of printed solder is judged from both, and terms that accurately represent the shape are extracted and displayed. Accordingly, it is possible to accurately determine whether or not the printed solder is formed, rather than performing two-dimensional measurement and three-dimensional measurement separately.

  The two-dimensional measurement step includes a step of measuring items of two-dimensional properties such as a bottom area and a pad area of the printed solder, and the three-dimensional measurement step includes a cross-sectional area, a protrusion area, and an average of the printed solder. It includes a step of measuring items of three-dimensional properties such as height, peak height, and volume. Then, it is characterized in that at least two measurement items are combined in a matrix to determine whether the printed solder is formed or not. As a result, it is possible to more accurately determine whether or not the printed solder is formed.

  To achieve the above object, in the printed solder inspection apparatus of the present invention, an optical system that captures a two-dimensional image of solder printed on a substrate, an optical system that captures a three-dimensional image of the printed solder, and a captured two-dimensional image Processing images and 3D images to measure items of 2D properties such as bottom area and pad area of the printed solder, and 3D properties such as cross-sectional area, protrusion area, average height, peak height, and volume And an inspection unit that determines the shape of the printed solder based on the measured item, and determines whether or not the printed solder is formed by combining at least two of the measured items in a matrix. It is characterized by that. Thereby, the printed solder test | inspection apparatus which has the said effect can be provided.

  Embodiments of the present invention will be described with reference to the drawings. The embodiments described below do not limit the invention according to the claims, and all the combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. Absent.

  FIG. 1 is a diagram showing an overall configuration of a printed solder inspection apparatus according to an embodiment of the present invention. This printed solder inspection apparatus 100 processes two-dimensional images and three-dimensional images of cream solder (printed solder) 10a, 10b, 10c printed on the inspection target substrate 10 to obtain two-dimensional property items and three-dimensional property items. It is characterized in that it has a function of measuring items and determining the shape of the printed solder and determining whether or not to form based on the measurement items. The configuration of the printed solder inspection apparatus 100 will be described below.

  The printed solder inspection apparatus 100 includes an illumination device (optical system) 20, an imaging device (optical system) 30, an image input storage unit (inspection unit) 50, an image processing unit (inspection unit) 60, a robot 70, a display device 74, An overall control unit (inspection unit) 80 and the like are provided.

  The illumination device 20 is mounted with a red-green LED illumination device 21 and a blue LED illumination device 22 for two-dimensional measurement. The red-green LED lighting device 21 is for extracting the pad 15 (see FIG. 3). The blue LED illumination device 22 is for detecting the printed solders 10a, 10b, and 10c. Furthermore, a slit illumination device 23 for three-dimensional measurement is incorporated. Slit light 24 is emitted from the slit illumination device 23. The slit light 24 has a length of about 30 mm and a width of about 0.1 mm. The lighting devices 21, 22, and 23 are controlled to be turned on / off by the overall control unit 80.

  The imaging device 30 is installed above the lighting device 20. The imaging device 30 includes a lens 32 for forming an image on an imaging element, and a camera 31 for converting the formed image into an electronic signal. The camera 31 may be of any type as long as it is an area camera, but a CMOS area camera is optimal for efficiently performing both two-dimensional measurement and three-dimensional measurement. The image pickup range at the time of two-dimensional measurement by the camera 31 is an image pickup device entire surface 40 shown in FIG. 2, for example, a range of 20.48 mm × 20.48 mm. In addition, the imaging range at the time of the three-dimensional measurement is the imaging region 41 shown in FIG. 2 including the portion irradiated with the slit light 24, for example, between 20.48 mm × 0.64 mm and 20.48 mm × 5.12 mm. Capturing images only in necessary areas. Which range is to be imaged is instructed from the overall control unit 80 via the image input storage unit 50.

  The image input storage unit 50 stores 2D measurement solder image data 51, 2D measurement pad image data 52, and 3D measurement image data 53 input from the camera 31. In the case of two-dimensional measurement, an image captured by lighting only the blue LED illumination device 22 is stored as two-dimensional measurement solder captured image data 51. An image captured by lighting only the red-green LED illumination device is stored as two-dimensional measurement pad captured image data 52. In the case of three-dimensional measurement, only the slit illumination device 23 is turned on and an image captured with the imaging range limited to the imaging area 41 shown in FIG. 2 is stored as captured image data 53 for three-dimensional measurement. Further, the picked-up images obtained by changing the position where the slit light 24 strikes little by little are stored one after another as the second and third pieces of picked-up image data 53 for three-dimensional measurement. As described above, in the three-dimensional measurement, a large number of images are captured in which the position where the slit light 24 strikes is changed little by little. Therefore, the three-dimensional measurement captured image data 53 includes at least 1024 image data. Yes.

  The image processing unit 60 processes the 2D measurement solder captured image data 51, the 2D measurement pad captured image data 52, and the 3D measurement captured image data 53 from the image input storage unit 50. Then, for example, two-dimensional property items / data 61 such as bottom areas and pad areas of the printed solders 10a, 10b, and 10c are measured, and three-dimensional such as a cross-sectional area, protrusion area, average height, peak height, and volume are measured. The property item / data 62 is measured. Although details will be described later, the shapes of the printed solders 10a, 10b, and 10c are determined based on the two-dimensional measurement item / data 61 and the three-dimensional measurement item / data 62, and the three-dimensional display data 63 is obtained. Further, whether or not the printed solders 10a, 10b, and 10c are formed is determined based on a determination table 64 in which at least two of the two-dimensional measurement items / data 61 and the three-dimensional measurement items / data 62 are selected and combined in a matrix. To do.

  The robot 70 includes an X-axis robot 71, a Y-axis robot 72, and a robot control unit 73. The X-axis robot 71 is fixed on the Y-axis robot 72. Further, the inspection target substrate 10 is fixed on the X-axis robot 71. The X-axis robot 71 and the Y-axis robot 72 are connected to a robot control unit 73, and the robot control unit 73 is connected to the overall control unit 80. The robot control unit 73 operates the X-axis robot 71 and the Y-axis robot 72 according to an instruction from the overall control unit 80, and moves the inspection target substrate 10 to the camera 31, the lens 32, and the illumination device 20 on the XY plane. It can be moved relatively. Thereby, the camera 31 can image an arbitrary position of the inspection target substrate 10.

  The display device 74 is a device that displays information essential for an operator to operate the printed solder inspection apparatus 100. The display device 74 also displays captured images and the like.

  The overall control unit 80 is for controlling the illumination device 20, the image input storage unit 50, the image processing unit 60, the robot 70, and the display device 74 that constitute the inspection apparatus 100. In the overall control unit 80, there are pad data 81, visual field assignment data 82, an imaging data storage area 83, an inspection data creation program 84, and an inspection execution program 85.

  FIGS. 3A and 3B are a plan view and a cross-sectional view taken along line AA showing the structure of the inspection target substrate 10. A wiring pattern 13 made of copper is formed on the substrate base 12. Of the wiring pattern 13, the portion connected to the terminal of the electronic component to be mounted, that is, the portion to which the printed solder 10 a, 10 b, 10 c is transferred is exposed as the pad 15. However, in some cases, the pad 15 may be gold-plated to increase conductivity. The region other than the pad 15 is covered and insulated by the resist 14. The portion of the wiring pattern 13 covered with the resist 14 is usually called an inner layer pattern 16 and is higher than the portion of the resist 14 without the wiring pattern 13 by the thickness of the wiring pattern 13.

  In the printed solder inspection apparatus 100 configured as described above, first, a two-dimensional measurement method for printed solder will be described. The X-axis robot 71 and the Y-axis robot 72 are controlled so that the inspection target substrate 10 can be imaged by the camera 31. Here, the printed solders 10a, 10b, and 10c (hereinafter simply referred to as 10x) are aggregates of solder grains having a diameter of about 20 μm to 30 μm, and thus the surface is a diffuse reflection surface when viewed macroscopically. On the other hand, the pad 15 is generally composed of gold or copper, and its surface is a mirror surface as compared with the surface of the printed solder 10x. Further, the surface of the resist 14 is also relatively mirror-finished.

  Therefore, only the blue LED illumination device 22 is turned on in the illumination device 20, an image of the printed solder 10 x is collected, and is stored in the image input storage unit 50 as the two-dimensional measurement solder captured image data 51. . Since the blue LED illumination device 22 is configured to illuminate from a considerably low position, the reflected light from the surface of the pad 15 and the resist 14 which are mirror surfaces does not go to the camera 31 and is opposite to the incident direction. To run away. On the other hand, the light reflected from the surface of the printed solder 10x, which is a diffuse reflection surface, has a relatively large amount of light component directed toward the camera 31. Therefore, the printed solder 10 x returns more reflected light to the camera 31 than the pad 15 and the resist 14. Based on this principle, the two-dimensional measurement solder-captured image data 51 is an image in which the printed solder 10x is captured relatively brightly.

  Subsequently, the red of the red-green LED lighting device 21 in the lighting device 20 is turned on, and an image of the printed solder 10x is collected, and this is taken as the two-dimensional measurement pad captured image data 52 in the image input storage unit 50. Remember. The surface of the resist 14 and the surface of the pad 15 are mirror surfaces as compared with the surface of the printed solder 10x. However, since the pad 15 is gold or copper and has a higher reflectance than the resist 14, the pad 15 emits more reflected light than the resist 14. It is returned to the camera 31. Furthermore, since the resist 14 is generally green, it has a complementary color relationship with the illumination color red and absorbs more illumination light, whereas the pad 15 reflects gold because it is a red color such as gold or copper. To do. With such an action, the pad 15 returns more reflected light to the camera 31 than the resist 14.

  Further, since the red-green LED illumination device 21 is configured to illuminate from a considerably high position, most of the reflected light from the surface of the pad 15 and the resist 14 that are mirror surfaces is the red-green LED illumination device 21. To the camera 31 in the same direction. On the other hand, the reflected light from the surface of the printed solder 10x that is the irregular reflection surface has a relatively reduced light component directed to the camera 31. Therefore, the pad 15 returns more reflected light to the camera 31 than the resist 14 and the printed solder 10x. Based on this principle, the two-dimensional measurement pad captured image data 52 is an image in which the pad 15 is captured relatively brightly. Then, the bottom area 101 (see FIG. 11) of the printed solder 10x can be obtained from the two-dimensional measurement solder captured image data 51. Further, the area of the pad 15 can be obtained from the two-dimensional measurement pad captured image data 52.

  Next, a three-dimensional measurement method for printed solder will be described. The X-axis robot 71 and the Y-axis robot 72 are controlled so that the slit light 24 strikes the inspection target substrate 10. As shown in FIG. 4, when the slit light 24 strikes the printed solder 10 x on the inspection target substrate 10, a slit light trace 242 is generated on the printed solder 10 x and a slit light trace 241 is generated on the inspection target substrate 10. . In the three-dimensional measurement captured image 53 captured by the camera 31, the slit light trace 242 on the printed solder 10x is the slit light trace 532, and the slit light trace 241 on the inspection target substrate 10 is the slit light trace 531. An image is taken as if the position is shifted by the height of the printed solder 10x.

  Assuming that the attachment angle of the slit light 24 from the surface of the inspection target substrate 10 is θ, the height of the printed solder 10x is obtained by multiplying the deviation amount by tan θ. Based on this idea, the coordinate difference in the Y direction on the image of the slit light trace 532 and the slit light trace 531 is obtained from the captured image data 53 for three-dimensional measurement, and if the value is multiplied by tan θ, the height of the printed solder 10x is measured. It ’s done. However, since only the height of the line segment hit by the slit light 24 can be measured with this alone, the volume most required for the inspection of the printed solder 10x cannot be measured. Therefore, the inspection target substrate 10 is operated relative to the unit of the camera 31 and the slit light 24. The operating direction is a direction orthogonal to the length direction of the slit light traces 241 and 242.

  As shown in FIG. 5A, a range in which three-dimensional measurement is desired is set as a height measurement region 11. As shown in FIG. 5B, the X-axis robot 71 and the Y-axis robot 72 are controlled so that the height measurement reference line 11 a that is the upper end of the height measurement region 11 enters the imaging region 41. Then, an image is taken at the position. Further, the imaging region 41 is moved by a necessary measurement resolution (for example, 20 μm) relative to the inspection target substrate 10 to capture an image. As shown in FIG. 5C, this operation is repeated until the height measurement reference line 11b, which is the lower end of the height measurement region 11, enters the imaging region 41 and the image is captured. If the range of the height measurement region 11 is 20.48 mm × 20.48 mm and imaging is repeated in units of 20 μm, the image data 53 for three-dimensional measurement captures 20.48 / 0.02 = 1,024 images. It will be. A part of the image image actually captured is shown in FIG. 6A, the real image data 53c in FIG. 6A is the board surface of the substrate 10 to be inspected, the real image data 53d in FIG. 6B is the portion where the height of the printed solder 10x is high, and the real image data 53e in FIG. This is how the portion of the solder 10x having a low height is captured.

  In the captured image data 53 for three-dimensional measurement, a measurement reference line 533 shown in FIG. 7 is defined. The measurement reference line 533 may be set anywhere in the area of the captured image data 53 for three-dimensional measurement. However, in this embodiment, the measurement reference line 533 is set almost in accordance with the slit light trace 531. The actual captured image data 53 for three-dimensional measurement has a size of 1,024 pixels × 32 pixels to 256 pixels, and the number of captured images is 1,024. Here, in order to explain the processing contents thereafter in an easy-to-understand manner, as shown in FIG. 8, the size of the three-dimensional measurement captured image data 53 is 10 pixels in the horizontal direction (X direction) and 10 pixels in the vertical direction (Y direction). Description will be made assuming that the number of pixels and the number of captured images is 10.

  The first image of the three-dimensional measurement captured image data 53 is processed. The y coordinate of the slit light traces 531 and 532 when x = 0 pixel on the image is obtained. Since the slit light 24 has a width of about 0.1 mm, it has a width of at least 5 pixels on the image. These five pixels do not have the same brightness value, but have a distribution in which the center is brighter and darker toward the outside. By obtaining a quadratic or quartic curve from these five pixels, the brightness distribution in the width direction of the slit light 24 can be accurately approximated. By setting the peak position of this curve to the y coordinate, the y coordinate value of the slit light at x = 0 can be accurately obtained in units of one pixel or less. The y coordinate is measured with the measurement reference line 533 as the origin. By multiplying this y coordinate by tan θ, the height from the measurement reference line 533 of the portion hit by the slit light 24 is obtained. This process is repeated from x = 1 to x = 9. Further, the same processing is repeated for the second to ninth three-dimensional measurement captured image data 53. When all the operations are completed, the heights at all points in the height measurement region 11 can be measured. In this embodiment, the measurement interval is 20 μm in both the XY directions.

  The measured height data is stored and saved in the three-dimensional measurement item / data 62. The three-dimensional measurement item / data 62 has a two-dimensional matrix structure of (10, 10) so that height information of all measured points can be recorded. When the height data at the m-th x = n (n = 0 to 9) is yn × tan θ (n = 0 to 9), this data is one of the three-dimensional measurement items / data 62 (10, 10). Whether to write in the cell will be described. Since x = n, the X coordinate is clearly X = n. Since it is the m-th sheet, Y = m is the basic Y coordinate. However, as is clear from FIG. 4, the point having the height of yn × tan θ is at a position shifted by −yn in the Y direction from the measurement reference line 533. Therefore, the Y coordinate of the cell storing the result is m-yn.

  Since the three-dimensional measurement item / data 62 is a two-dimensional matrix of (10, 10), the XY coordinate value of the cell is an integral multiple of the unit (20 μm in this embodiment). If m-yn does not match the integer value of the unit, it is written to the cell with the closest Y coordinate value. In summary, when the y coordinate of the slit light trace 532 at x = n in the m-th three-dimensional measurement captured image data 53 is yn, the height data yn × tan θ is the cell of the three-dimensional measurement item / data 62. (N, <m-yn>) is written. However, <m-yn> is the “integral multiple of unit” closest to m-yn. In this way, the three-dimensional measurement item / data 62 of the height measurement region 11 is obtained. Since the measurement reference line 533 is aligned with the slit light trace 531, the three-dimensional measurement item / data 62 records the unevenness measured from the upper surface of the inspection target substrate 10. By integrating this data, the volume of the printed solder 10x can be obtained. Further, an image as shown in FIG. 9 can be obtained by performing three-dimensional graphic processing on the stereoscopic display data 63.

  As described above, the height of the printed solder 10x can be measured on the basis of the upper surface of the substrate 10 to be inspected. Three-dimensional measurement is performed in units of 11 height measurement regions. The height measurement area 11 is automatically generated when inspection data is created. Therefore, the height measurement reference line 11a and the height measurement reference line 11b are also automatically defined. As shown in FIG. 10, the height measurement reference plane 17 can be obtained by measuring the upper surface height of the inspection target substrate 10 on the height measurement reference line 11a and the height measurement reference line 11b. The height or volume of the printed solder 10x described so far is measured using this height measurement reference surface 17 as a reference.

  Here, consider a case where the same three-dimensional measurement as described above is performed on a raw substrate. Since the raw board is a board on which cream solder is not printed, the height obtained by measuring the height of the printed solder is a pad using the height measurement reference surface 17 as a measurement reference, as shown in FIG. The upper surface heights of 15a, 15b, and 15c are 18a, 18b, and 18c. The upper surface heights 18a, 18b, and 18c of the pads 15a, 15b, and 15c are measured in advance by measuring the raw substrate, and the height from the reference surface of the pad data 81 is stored for each pad 15a, 15b, and 15c. Keep it. Then, the height of the printed solder is measured for each of the pads 15a, 15b, and 15c, and the height from the reference plane stored for each of the pads 15a, 15b, and 15c is subtracted from the result. Thereby, the printed solder height becomes a value measured on the basis of the upper surface of the pads 15a, 15b, and 15c. In this way, the raw substrate is measured at the final stage when the inspection data is created, and the heights of the pads 15a, 15b, and 15c from the reference surface with respect to the automatically generated height measurement reference surface 17 are measured and stored. Thus, the height of the printed solder can be measured based on the upper surface reference of the pads 15a, 15b, and 15c.

  By the above two-dimensional measurement method, the two-dimensional property item / data 61 such as the bottom area 101 and the pad area of the printed solder 10x shown in FIG. 11 can be measured. Further, the three-dimensional measurement method can measure the three-dimensional property items and data 62 such as the cross-sectional area 102, the protrusion area 103, the average height 104, the peak height 105, and the volume 106 of the printed solder 10x shown in FIG. it can. In other words, the geometric shape of the printed solder 10x as shown in FIG. 11 can be determined more accurately from these measurement items. The respective measurement items / data 61 and 62 are not limited to the above-described items, and may be anything that represents the two-dimensional property or the three-dimensional property of the printed solder 10x.

  On the other hand, in the test for determining whether or not each of the measurement items / data 61 and 62 is within the acceptable range with respect to the allowable value, for example, when the bottom area 101 is larger than the allowable value, Only the inspection result “is a large failure” is displayed. The same applies to the determination of other measurement items / data 61 and 62. Such a display of the inspection result is correct from the geometric shape of the printed solder 10x, but does not necessarily match the concept expressing the defective state of the printed solder 10x. For example, “a defect having a bottom area larger than an allowable value” should be expressed as “smear”. Furthermore, the “defective state whose volume is less than the permissible value” clearly differs depending on whether the average height is low (thin) and low, or lacked and low. “Small volume” + “Low height” + “Normal bottom area” should be described as “smear”, “Low volume” + “Normal height” + “Low bottom area” It should be expressed as “lack”. Therefore, all the geometric elements of the printed solder 10x are measured by the two-dimensional measuring method and the three-dimensional measuring method, and further, all these elements are taken into consideration to determine whether or not the printed solder 10x is formed. It becomes possible.

  FIG. 12 is a diagram showing a specific determination table using the bottom area and the pad area of the printed solder. By comparing the measured bottom area 101 of the printed solder 10x with an upper limit allowable value and a lower limit allowable value set in advance, it is classified as under, appropriate, or excessive. On the other hand, the measured pad area is also classified into under, appropriate, and excessive by comparing with a preset upper limit allowable value and lower limit allowable value. Then, by using the determination table 64 in which the above-mentioned under, appropriate, and over are combined in a matrix, it is determined to which of the regions 1 to 9 the classification of the printed solder 10x and the corresponding pad is applied.

  For example, when the bottom area 101 of the printed solder 10x is excessive and the pad area is insufficient or appropriate (region 1 or region 2), the inspection result “smudge” is displayed on the display device 74. Similarly, when the bottom area 101 of the printed solder 10x is excessive or appropriate and the pad area is excessive (region 3 or region 6), the inspection result “shift” is displayed on the display device 74. In addition, when the bottom area 101 of the printed solder 10x is appropriate and the pad area is appropriate (region 5), an inspection result “good” is displayed on the display device 74. Further, when the bottom area 101 of the printed solder 10x is too small and the pad area is appropriate or excessive (region 8 or region 9), the inspection result “blur” is displayed on the display device 74.

  FIG. 13 is a diagram illustrating a specific determination table using the volume of the printed solder and the bottom area of the printed solder. By comparing the measured volume of the printed solder 10x with an upper limit allowable value and a lower limit allowable value set in advance, the volume is classified into under, appropriate, and excessive. On the other hand, the measured bottom area 101 of the printed solder 10x is also classified into under, appropriate, and excessive by comparing with the preset upper and lower permissible values. Then, by using the determination table 64 in which the above-described under, appropriate, and over are combined in a matrix, it is determined to which of the regions 1 to 9 the classification of the printed solder 10x is applied.

  For example, when the volume of the printed solder 10x is excessive and the bottom area 101 of the printed solder 10x is appropriate or excessive (region 2 or region 3), an inspection result “excess” is displayed on the display device 74. Similarly, when the volume of the printed solder 10x is appropriate and the bottom area 101 of the printed solder 10x is appropriate (region 5), an inspection result “good” is displayed on the display device 74. When the volume of the printed solder 10x is too small or appropriate and the bottom area 101 of the printed solder 10x is excessive (region 6 or region 9), the inspection result “smudge” is displayed on the display device 74. Further, when the volume of the printed solder 10x is too small and the bottom area 101 of the printed solder 10x is too small or appropriate (region 7 or region 8), an inspection result “blur” is displayed on the display device 74.

  In the above-described embodiment, the determination table is a two-dimensional matrix. However, the determination table is not limited to this, and the determination table may be determined as a three-dimensional or higher matrix. Although the two-dimensional measurement and three-dimensional measurement cameras are shared, the essence of the invention does not change at all even if the two-dimensional measurement camera and the three-dimensional measurement camera are individually mounted.

1 is a diagram illustrating an overall configuration of a printed solder inspection apparatus according to an embodiment of the present invention. It is a perspective view which shows the imaging range by the camera of FIG. It is the top view and AA sectional view taken on the line which show the structure of the test object board | substrate of FIG. It is a figure which shows the case where it image | photographs by applying slit light to a test object board | substrate. It is a top view which shows the positional relationship of the imaging area and imaging range of a three-dimensional measurement on a test object board | substrate. It is a figure which shows typically the way of actual reflection of the slit light in the imaging area of a three-dimensional measurement. It is a figure which shows the imaging area of the three-dimensional measurement on the image pick-up element of a camera. It is a figure which shows the structure of a three-dimensional measurement item. It is the figure which performed the three-dimensional graphic process for the stereoscopic display data. It is the figure which showed the positional relationship of a height measurement reference line, a height measurement reference plane, and pad surface height. It is a perspective view which shows the external appearance shape of printed solder. It is a figure which shows the specific determination table using the bottom part area and pad area of printed solder. It is a figure which shows the specific determination table using the volume of printed solder, and the bottom part area of printed solder.

Explanation of symbols

  10 Substrate 10a, 10b, 10c, 10x Printed solder, 11 Height measurement area, 11a, 11b Height measurement reference line, 12 Substrate base material, 13 Wiring pattern, 14 Resist, 15 Pad, 16 Inner layer pattern, 17 Height measurement reference plane, 18a, 18b, 18c Pad top surface height, 20 illumination device, 21 red-green LED illumination device, 22 blue LED illumination device, 23 slit illumination device, 24 slit light, 30 imaging device, 31 camera, 32 Lens, 40 Image sensor entire surface, 41 Image area, 50 Image input storage section, 51 Two-dimensional measurement solder image data, 52 Two-dimensional measurement pad image data, 53 Three-dimensional measurement image data, 531, 532 Slit Light trace, 533 measurement reference line, 60 image processing unit, 61 2D measurement item Data, 62 3D measurement item / data, 63 3D display data, 64 Judgment table, 70 Robot, 71 X-axis robot 71, 72 Y-axis robot 72, 73 Robot control unit, 74 Display device, 80 Overall control unit, 81 Pad Data, 82 Field allocation data, 83 Image data storage area, 84 Inspection data creation program, 85 Inspection execution program, 100 Print solder inspection device, 101 Bottom area, 102 Cross-sectional area, 103 Protrusion area, 104 Average height, 105 Peak height 106 volumes

Claims (5)

Two-dimensional measurement and three-dimensional measurement of the solder printed on the substrate;
And a step of determining the shape of the printed solder using the two-dimensional measurement result and the three-dimensional measurement result. Two-dimensional measurement and three-dimensional measurement of the solder printed on the substrate;
And a step of determining whether or not the printed solder is formed using the two-dimensional measurement result and the three-dimensional measurement result. The two-dimensional measurement step includes a step of measuring two-dimensional property items such as a bottom area and a pad area of the printed solder, and the three-dimensional measurement step includes a cross-sectional area, a protrusion area, and an average height of the printed solder. The printed solder inspection method according to claim 1, further comprising a step of measuring three-dimensional property items such as peak height and volume. The printed solder inspection method according to claim 3, wherein whether or not the printed solder is formed is determined by combining at least two measurement items in a matrix. An optical system for capturing a two-dimensional image of the solder printed on the substrate;
An optical system for capturing a three-dimensional image of the printed solder;
The captured 2D image and 3D image are processed to measure items of 2D properties such as the bottom area and pad area of the printed solder, and the cross-sectional area, protrusion area, average height, peak height, volume, etc. An inspection unit that measures the three-dimensional property item of the image, determines the shape of the printed solder based on the measurement item, and determines whether or not the printed solder is formed by combining at least two of the measurement items in a matrix shape And a printed solder inspection apparatus.

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