JP2005345142A - Device and method for inspecting chip component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for inspecting a chip component capable of inspecting easily the chip component of an inspection object by brightness thereof. <P>SOLUTION: This inspection device 2 is provided with an outer shape area determining part 7 for determining an outer shape area of the chip component 1 on the basis of an image signal of the chip component 1 imaged by a camera 6, a brightness measuring area setting part 8 for setting a brightness measuring area in response to the outer shape area of the chip component 1 determined by the outer shape area determining part 7, an average brightness computing part 9 for computing an average brightness value in the brightness measuring area, a threshold value setting part 11 for setting an upper limit threshold value and a lower limit threshold value by adding and subtracting an upper limit off-set value and a lower limit off-set value to/from the computed average brightness value, a binarization image processing 12 for binarization-processing the image signal of the chip component 1, based on the upper limit threshold value and the lower limit threshold value set by the threshold value setting part 11, and a monitor 14 for displaying the binarization-processed image signal. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a chip component inspection apparatus and inspection method.

As an appearance inspection of chip parts, items such as chipping, chipping, unpeeled chipping, foreign matter adhering to the surface, or cracks are inspected. Has been. As a technique in such a field, there is a technique described in Japanese Patent Laid-Open No. 7-190739. In the chip inspection apparatus disclosed in this publication, a comparison reference chip is prepared, images of the comparison reference chip and the inspection target chip are acquired at a plurality of illumination levels, and the average gray level of the comparison reference chip is calculated. The chip component is inspected by performing correction for offsetting the difference from the average gray level of the inspection target chip.
Japanese Patent Laid-Open No. 7-190739

  However, the inspection apparatus as described above requires a comparison reference chip, and if the imaging conditions such as the illumination intensity change, it is necessary to re-image the reference image of the comparison reference chip. It is also necessary to switch the illumination level. Therefore, the inspection was complicated.

  Therefore, an object of the present invention is to provide a chip component inspection apparatus and inspection method that can easily inspect a chip component to be inspected.

  The chip component inspection apparatus according to the present invention is calculated by the average luminance calculation means for calculating the average luminance value of the luminance measurement area in the chip component and the average luminance calculation means from the image signal of the chip component to be inspected. A threshold setting unit configured to set a threshold based on the average luminance value; and a binarized image processing unit configured to binarize the image signal of the chip component based on the threshold set by the threshold setting unit. Features.

  According to this chip component inspection apparatus, even if the brightness is different for each chip component due to individual differences of the chip components to be inspected, the threshold is set based on the average luminance value for each chip component. Chip components can be inspected without being affected by changes in luminance of the chip components. Therefore, erroneous determination is reduced as compared with the case where the threshold value is fixedly set, and the chip component can be properly inspected. At this time, since a comparison reference chip is not particularly required separately from the chip component to be inspected, it is suitable for high-speed processing.

  Further, in the above-described chip component inspection apparatus, an outer region determination unit that determines an outer region of the chip component from the image signal of the chip component, and an outer region of the chip component determined by the outer region determination unit It is preferable to further include a luminance measurement area setting means for setting the luminance measurement area. With this configuration, even if the size or shape of the outer shape of the chip component is different, the luminance measurement area is set according to the outer shape of the chip component, so that the chip component can be properly inspected.

  The chip component inspection method according to the present invention is calculated in an average luminance calculation step for calculating an average luminance value of a luminance measurement area in the chip component from an image signal of the chip component to be inspected, and an average luminance calculation step. A threshold setting step for setting a threshold based on the average brightness value, and a binarized image processing step for binarizing the image signal of the chip component based on the threshold set by the threshold setting step. It is characterized by.

  According to this chip component inspection method, even if the luminance differs for each chip component due to individual differences in the chip components to be inspected, the threshold is set based on the average luminance value for each chip component. Chip components can be inspected without being affected by changes in luminance. Accordingly, erroneous determination is reduced as compared with the case where the threshold value is fixedly set, and the chip component can be properly inspected. At this time, since a comparison reference chip is not particularly required separately from the chip component to be inspected, it is suitable for high-speed processing.

  The chip component inspection method according to the present invention includes an outer region determination step for determining an outer region of a chip component from an image signal of the chip component to be inspected, and the chip component determined in the outer region determination step. A luminance measurement area setting step for setting a luminance measurement area according to the outer region, an average luminance calculation step for calculating an average luminance value of the luminance measurement area in the chip component, and an average luminance value calculated in the average luminance calculation step A threshold value setting step for setting a threshold value based on the threshold value, and a binarized image processing step for binarizing the image signal of the chip component based on the threshold value set by the threshold value setting step. .

  According to this chip component inspection method, even if the size or shape of the outer shape of the chip component is different, the luminance measurement area is set according to the outer shape of the chip component, so that the chip component can be properly inspected. it can. In addition, even if the brightness varies from chip part to chip part due to individual differences in the chip parts to be inspected, the threshold is set based on the average brightness value of each chip part, so it is not affected by changes in the brightness of the chip part. In addition, it is possible to inspect chip parts. Accordingly, erroneous determination is reduced as compared with the case where the threshold value is fixedly set, and the chip component can be properly inspected. At this time, since a comparison reference chip is not particularly required separately from the chip component to be inspected, it is suitable for high-speed processing.

  According to the present invention, a chip component to be inspected can be easily inspected by its brightness.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of an inspection apparatus and inspection method for chip parts according to the present invention will be described in detail with reference to the accompanying drawings.

[Configuration of inspection equipment for chip parts]
FIG. 1 is a block diagram showing the configuration of an inspection device 2 for chip parts 1. The chip component 1 is illuminated by a ring-shaped lighting fixture 3 and imaged by a camera 6 to which a lens 4 is attached. An imaging signal of the chip part 1 imaged by the camera 6 is transmitted to the inspection device 2.

  The inspection apparatus 2 includes an outer region determination unit 7, a luminance measurement area setting unit 8, an average luminance calculation unit 9, a threshold setting unit 11, a binarized image processing unit 12, an interface 13, and a monitor 14. The interface 13 is connected to a keyboard 16 for inputting character information and a mouse 17 as a pointing device. The inspection device 2 is physically composed of a CPU, RAM, ROM, and the like.

  FIG. 2 is a plan view of the chip component 1. As shown in FIG. 2, a ceramic base 1 a and an electrode portion 1 b appear on the surface of the chip component 1.

  Returning to FIG. 1, the outer region determination unit 7 receives the image signal including the luminance information of the chip component 1 transmitted from the camera 6 and obtains the outer region of the chip component 1. That is, the outer region determination unit 7 determines the boundary between the chip component 1 and the background of the chip component 1 based on luminance, and obtains the outer region coordinates of the chip component 1 (see FIG. 2).

  The luminance measurement area setting unit 8 sets the luminance measurement area BA according to the coordinates of the outer region of the chip part 1 determined by the outer region determination unit 7. That is, the luminance measurement area setting unit 8 is a luminance measurement area BA within the outer shape area of the chip component 1, which is a total of 11 squares, 5 at the center of the substrate area 1 a and 3 at the left and right edges. Luminance measurement areas BA1 to BA11 are set (see FIG. 2).

The setting of the center positions of the luminance measurement areas BA1 to BA11 is as follows. Here, the horizontal length of the chip component 1 is L, and the vertical width is H. Moreover, each length shown in FIG. 2 is defined as follows as an example.
Length of one side of each luminance measurement area BA = H / 10 (1)
Length A = L / 2 (2)
Length B = H / 7 (3)
Length C = L / 20 (4)
Length D = H / 2 (5)
Length E = H / 5 (6)

  Of the luminance measurement areas BA1 to BA5 set at the center of the substrate region 1a, the center of the luminance measurement area BA1 located at the center is located at the center of the chip part 1 and has a length A from both left and right edges. It is a position, and is a position of length D from the upper and lower edges. The center of the luminance measurement area BA2 is separated from the center of the luminance measurement area BA1 by a length B in the left lateral direction and a length E in the upward direction. The center of the luminance measurement area BA3 is separated from the center of the luminance measurement area BA1 by a length B in the left lateral direction and a length E in the downward direction. The center of the luminance measurement area BA4 is separated from the center of the luminance measurement area BA1 by a length B in the right lateral direction and a length E in the upward direction. The center of the luminance measurement area BA5 is separated from the center of the luminance measurement area BA1 by a length B in the right lateral direction and a length E in the downward direction.

  Of the luminance measurement areas BA6 to BA8 set at the left edge of the substrate region 1a, the center of the luminance measurement area BA6 is separated from the left edge by a length C in the right lateral direction and is long from the upper and lower edges. This is the position D (center in the vertical direction). The center of the luminance measurement area BA7 is separated from the center of the luminance measurement area BA6 by a length E in the upward direction. The center of the luminance measurement area BA8 is spaced downward by a length E from the center of the luminance measurement area BA6.

  In addition, among the luminance measurement areas BA9 to BA11 set at the right edge of the substrate region 1a, the center of the luminance measurement area BA9 is separated from the right edge by a length C in the left lateral direction and is long from the upper and lower edges. This is the position D (center in the vertical direction). The center of the luminance measurement area BA10 is separated from the center of the luminance measurement area BA9 by a length E in the upward direction. The center of the luminance measurement area BA11 is separated from the center of the luminance measurement area BA9 by a length E in the downward direction.

  Thus, the positions of the luminance measurement areas BA1 to BA11 are set according to the size and shape of the chip component 1. Therefore, even if the size or shape of the outer shape of each chip component 1 is different, the luminance measurement area BA is set according to the size and outer shape of the chip component 1.

  The average luminance calculation unit 9 calculates average luminance values in the luminance measurement areas BA1 to BA11 set by the luminance measurement area setting unit 8. FIG. 3 shows an arrangement of pixels in each luminance measurement area BA. The average luminance calculation unit 9 calculates the average luminance value of each luminance measurement area BA from the luminance value in each pixel (01 to 42) of each luminance measurement area BA shown in FIG. The average luminance value of is calculated.

  Returning to FIG. 1, the threshold setting unit 11 sets an upper limit threshold and a lower limit threshold for binarizing the image signal based on the average luminance value calculated by the average luminance calculation unit 9. Here, the upper limit threshold and the lower limit threshold are such that the luminance of the substrate 1a in which abnormality such as cracking, chipping, foreign matter adhesion, or cracking of the chip component 1 occurs exceeds the upper limit threshold or falls below the lower limit threshold. The luminance base 1a within the range of the upper threshold value is set to be normal. The upper limit threshold is set by adding a predetermined upper limit offset value to the average luminance value, and the lower limit threshold is set by subtracting a predetermined lower limit offset value from the average luminance value. The upper limit offset value and the lower limit offset value are set in the threshold setting unit 11 in advance. Further, the upper limit offset value and the lower limit offset value are appropriately determined in advance by measuring the luminance of the normal substrate and the luminance of the abnormal substrate using the plurality of chip components 1.

  Although the luminance differs for each chip component 1 due to individual differences of the chip component 1, the upper threshold and the lower threshold are set based on the average luminance value of the chip component 1. The chip component 1 can be inspected so as not to be affected by the change. Therefore, erroneous determination is reduced as compared with the case where the upper limit threshold and the lower limit threshold are fixedly set. Moreover, even if the brightness | luminance of the chip component 1 changes with a rod, the test | inspection of the chip component 1 can be performed appropriately. At this time, a comparative reference chip is not particularly required separately from the chip component 1 to be inspected. Therefore, this inspection apparatus 2 is also suitable for high-speed processing.

  The binarized image processing unit 12 binarizes the image signal of the chip component 1 based on the upper limit threshold and the lower limit threshold set by the threshold setting unit 11. That is, if the luminance value of the pixel in the image signal of the chip component 1 is a value in the range from the upper threshold value to the lower threshold value, a display value (for example, “0”) that is displayed in white on the monitor 14 is set. If the luminance value of the pixel in the image signal exceeds the upper threshold or falls below the lower threshold, a display value (for example, “1”) displayed in black on the monitor 14 is set.

  The monitor 14 receives the display value set by the binarized image processing unit 12 by the binarized image processing unit 12, and is within the range from the upper limit threshold that is a normal range to the lower limit threshold for each pixel of the image signal of the chip component 1. The pixels having the luminance value are displayed in white, and the pixels having the luminance value outside the range from the upper limit threshold which is the abnormal range to the lower limit threshold are displayed in black.

[Inspection method of chip parts]
The inspection method for the chip component 1 will be described with reference to FIGS. FIG. 4 is a flowchart of processing executed in the inspection device 2 for the chip part 1.

  The camera 6 images the chip part 1 illuminated by the lighting fixture 3 and transmits an image signal of the chip part 1 to the inspection device 2.

  The outer region determination unit 7 of the inspection apparatus 2 receives the image signal of the chip part 1 transmitted from the camera 6 and determines the boundary between the chip part 1 and the background of the chip part 1 on the coordinates on the coordinates from the difference in luminance. The outline area of the component 1 is determined (S101).

  Next, 11 luminance measurement areas BA (refer to FIG. 2) of the substrate region 1a are set according to the coordinates of the outer region of the chip part 1 determined by the luminance measurement area setting unit 8 (S102).

  Further, the average luminance calculation unit 9 calculates the average luminance value of all the luminance measurement areas BA1 to BA11 from the luminance value in each pixel (pixel coordinates 01 to 42) (see FIG. 3) in each luminance measurement area BA ( S103).

  The threshold setting unit 11 adds the preset upper limit offset value to the average luminance value to set the upper limit threshold, and subtracts the preset lower limit offset value to the average luminance value to set the lower limit threshold. (S104).

  Subsequently, based on the upper limit threshold and the lower limit threshold set by the threshold setting unit 11, based on whether the luminance of each pixel of the chip component 1 belongs to the range between the upper limit threshold and the lower limit threshold. A binarization process is performed by the binarized image processing unit 12 (S105). At this time, if the luminance value of the pixel in the image signal of the chip component 1 is within the range from the upper limit threshold to the lower limit threshold, a display value to be displayed in white on the monitor 14 is set, and if it is outside the range from the upper limit threshold to the lower limit threshold. For example, the display value displayed in black on the monitor 14 is set.

  In addition, on the monitor 14, based on the display value set by the binarized image processing by the binarized image processing unit 12, for each pixel of the image signal of the chip component 1, the upper limit threshold that is a normal range is set to the lower limit. Pixels within the threshold range are displayed in white, and pixels outside the upper limit threshold, which is an abnormal range, and outside the lower threshold range are displayed in black (S106). By the above inspection method, the base portion where the chip component 1 is abnormal, such as cracks, chips, foreign matter adhesion, cracks, etc., is displayed in black.

  FIG. 5 shows an example of chip component inspection. In FIG. 5A, as shown in this embodiment, the image signal of the chip component is binarized by the inspection apparatus 2 in which the upper limit threshold and the lower limit threshold are determined according to the average luminance value. It is an image. That is, the left side of FIG. 5A shows an image of a chip part, and the right side shows an image subjected to binarization processing. In addition, the images inspected for two different chip components are shown side by side. FIG. 5B is an image in which the image signal of the chip component is binarized by the inspection apparatus in which the upper and lower thresholds are fixedly set regardless of the average luminance value having individual differences. is there. Two chip parts arranged side by side are in order with the two chip parts shown in FIG.

  As shown in FIG. 5A, in the upper chip component, the chipping is displayed in black on the right edge portion of the substrate 1a, and the central portion of the substrate 1a is white and normal. On the other hand, the upper chip part in FIG. 5B is obtained by inspecting the same chip part as the upper chip part in FIG. 5A, but the central part of the substrate 1a is normal although it is normal. Is displayed in black. Thus, it can be seen that it is important to set the upper and lower thresholds for determining the normality / abnormality of the chip component 1 according to the individual differences in the luminance values. Note that the binarized images of the chip parts shown on the lower side of FIGS. 5A and 5B are both linear abnormalities extending downward to the lower left edge. The part (the part displayed in black on the straight line) appears. That is, both of FIG. 5 (a) and FIG. 5 (b) are cases where an abnormal part has been confirmed.

  Note that the inspection device 2 and the inspection method for the chip component 1 according to the present invention are not limited to the above embodiment.

  In the above embodiment, two threshold values, an upper limit threshold value and a lower limit threshold value, are set when performing binarized image processing. However, depending on the luminance characteristics of the chip component 1, one threshold value is set and binarized image processing is performed. May be performed.

  Further, the position of the luminance measurement area BA does not have to be the 11 positions shown in FIG. 2, and may be present, for example, at positions evenly scattered in the region of the substrate 1 a. Further, the number of luminance measurement areas BA may be arbitrarily set. Even if the chip component 1 has a non-rectangular shape, it is preferable that the position of the luminance measurement area BA can be set according to the shape of the chip component 1.

1 is a configuration block diagram showing an embodiment of an inspection device for chip parts according to the present invention. It is a top view of a chip component. It is the schematic which shows the arrangement | sequence of the pixel in a brightness | luminance measurement area. It is a flowchart of the process performed in the apparatus for a test | inspection. FIG. 5A shows an example of chip component inspection. FIG. 5A is an image of a chip component that has been subjected to binarized image processing by an inspection apparatus in which an upper limit threshold and a lower limit threshold are determined according to an average luminance value. FIG. 5B is an image of a chip component that has been subjected to binarized image processing by an inspection apparatus in which an upper limit threshold and a lower limit threshold are fixedly set.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Chip component, 2 ... Inspection apparatus, 7 ... Outline area determination part, 8 ... Luminance measurement area setting part, 9 ... Average brightness calculating part, 11 ... Threshold setting part, 12 ... Binary image processing part, BA ... Luminance measurement area.

Claims (4)

Average luminance calculation means for calculating an average luminance value of a luminance measurement area in the chip component from the image signal of the chip component to be inspected;
Threshold setting means for setting a threshold based on the average brightness value calculated by the average brightness calculating means;
A chip component inspection apparatus comprising: binarized image processing means for binarizing the image signal of the chip part based on the threshold value set by the threshold value setting means. From the image signal of the chip component, an outer region determination unit that determines an outer region of the chip component;
2. The chip component according to claim 1, further comprising: a luminance measurement area setting unit that sets the luminance measurement area according to an outer region of the chip component determined by the outer region determination unit. Inspection device. An average luminance calculation step for calculating an average luminance value of a luminance measurement area in the chip component from an image signal of the chip component to be inspected,
A threshold setting step for setting a threshold based on the average luminance value calculated in the average luminance calculation step;
A chip component inspection method comprising: a binarized image processing step of binarizing the image signal of the chip component based on the threshold set in the threshold setting step. From the image signal of the chip component to be inspected, an outer region determination step for determining the outer region of the chip component;
A luminance measurement area setting step for setting a luminance measurement area according to the outline region of the chip part determined in the outer region determination step;
An average luminance calculation step for calculating an average luminance value of the luminance measurement area in the chip component;
A threshold setting step for setting a threshold based on the average luminance value calculated in the average luminance calculation step;
A chip component inspection method comprising: a binarized image processing step of binarizing the image signal of the chip component based on the threshold set in the threshold setting step.

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