JP2009103512A - Wiring pattern treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect with high precision defects in a wiring pattern formed on a wiring board. <P>SOLUTION: A wiring pattern display apparatus irradiates the wiring board 1 with light and displays the wiring pattern 2 formed on the wiring board 1 by means of the reflected light of the light. The apparatus comprises: a plurality of irradiation means for generating a plurality of lights having different wavelengths and irradiating the wiring board 1 with the lights from a plurality of different directions; a wavelength separation means for separating the wavelengths of the reflected lights of the lights irradiated on the wiring pattern 2 from the irradiation means; and a display section for displaying the wiring pattern 2 in accordance with the light with the wavelength separated by the wavelength separation means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wiring pattern processing device, and more particularly to a wiring pattern processing device such as a wiring pattern display device or an inspection device for inspecting a wiring pattern of an electronic component such as a printed wiring board.

  In general, automatic visual inspection devices for printed wiring boards are roughly divided into two types, mainly reflective and fluorescent. The reflection type inspection apparatus illuminates a wiring pattern and captures the reflected image with a camera. This reflection type is inexpensive and widely used because the apparatus can be easily configured, but has a drawback that it is difficult to distinguish the substrate from the base material at the reflection level, and it is easy to overlook fine wiring shorts and copper residue. On the other hand, the fluorescence type inspection apparatus is a system in which excitation light having a short wavelength is irradiated onto a wiring pattern, and weak fluorescence generated from a substrate is imaged by a camera. In this fluorescent type, the metal wiring can be seen as a silhouette, so it is possible to accurately detect fine shorts and copper residue of the wiring that are easily overlooked in the reflection type, while the surface of the copper pattern is locally chipped and thinned. It is easy to miss a defect called dishdown, and the current situation is that the spread of the device is delayed because the device is expensive.

JP 59-232344 A Harahiko, “Printed Wiring Board Appearance Inspection Technology”, Journal of Japan Institute of Electronics Packaging, July 2002, Vol. 5, no. 4, P.I. 323

  Recently, the detection rate has been improved by adding not only incident-light illumination but also oblique illumination to the reflective illumination. However, when oblique illumination is strengthened in the reflection type, it is easy to find fine shorts and remaining copper, but there is a drawback that it is easy to miss dishdown that has been detected conventionally. For the above reasons, in order to expect a detection rate of nearly 100%, automatic visual inspection equipment for printed wiring boards either inspects twice using the reflection type and the fluorescence type, or switches the illumination direction using the reflection type. Had to be inspected twice. But in any case, it was not realistic from the viewpoint of cost.

  An object of the present invention is to detect a defect in a wiring pattern formed on a wiring board with high accuracy.

  In order to achieve the above object, a wiring pattern processing apparatus of the present invention irradiates light on a wiring board and displays a wiring pattern formed on the wiring board by the reflected light. A plurality of irradiating means for generating a plurality of lights and irradiating the wiring substrate from a plurality of different predetermined directions, and a wavelength for separating the wavelength of the reflected light of the light irradiated to the wiring pattern from the irradiating means A separation unit and a display unit that displays the wiring pattern according to light having a wavelength separated by the wavelength separation unit can be provided.

Further, the direction in which the irradiating means irradiates light is perpendicular or oblique to the wiring board,
The wiring pattern can be displayed in accordance with the direction of irradiation by the irradiation means.

  Further, the wavelength irradiated from the irradiation unit can be configured to be an electromagnetic wave from 300 nanometers to 1200 nanometers.

  The wavelength separation means can be configured to be a filter for identifying a predetermined wavelength.

  In addition, in a wiring pattern inspection apparatus that irradiates light to a wiring board and detects defects in the wiring pattern formed on the wiring board by the reflected light, a plurality of lights having different wavelengths are generated to the wiring board. A plurality of irradiating means for irradiating light from a plurality of different predetermined directions, a wavelength separating means for separating the wavelength of reflected light of the light emitted from the irradiating means to the wiring pattern, and wavelengths separated by the wavelength separating means An image processing unit that performs image processing on the wiring pattern in response to the light, and whether or not the wiring pattern is defective is determined based on the image processing data of the wiring pattern image-processed by the image processing unit And a defect determination means.

  According to the present invention, a defect in a wiring pattern formed on a wiring board can be detected with high accuracy by irradiating the wiring board with light of different wavelengths and detecting the wiring pattern according to the wavelength of the reflected light. Can do.

Next, the best mode for carrying out the present invention will be described based on the following embodiments with reference to the drawings.
[Example 1]
FIG. 1 is a diagram illustrating a configuration example of a wiring pattern display device according to the present embodiment.

  The wiring pattern display device includes a halogen lamp 3, a blue filter 4, a half mirror 5, a halogen lamp 6, a red filter 7, a dichroic mirror 8, a blue filter 9, a monochrome imaging camera unit 10, a red filter 11, a monochrome imaging camera unit 12, The camera controller 13, the camera controller 14, the image monitor 15, and the image monitor 16 are configured.

  The halogen lamp 3 is a light source that irradiates an object to be inspected, and is a source of blue light. The blue filter 4 transmits blue light out of the light emitted from the halogen lamp 3. The half mirror 5 vertically illuminates the blue light transmitted through the blue filter 4. The halogen lamp 6 is a light source that irradiates an object to be inspected, and is a source of red light. Further, the irradiation direction from the light source is oblique with respect to the inspection object. The red filter 7 transmits red light out of the light emitted from the halogen lamp 6. The dichroic mirror 8 selectively transmits blue light among the reflected light of the inspection object. The blue filter 9 transmits blue light. The monochrome imaging camera unit 10 images blue light that has been wavelength-separated. The red filter 11 transmits red light. The monochrome imaging camera unit 12 images red light that has been wavelength-separated. The camera controller 13 performs control to display data captured by the monochrome imaging camera unit 10 on the image monitor 15. The camera controller 14 performs control to display data captured by the monochrome imaging camera unit 12 on the image monitor 16. The image monitors 15 and 16 display an image of the inspection object.

  Next, an operation for displaying a defect in a wiring pattern by the wiring pattern display device will be described.

  The printed wiring board 1 having a fine short-circuit defect and a dish-down defect and its wiring pattern 2 are vertically illuminated by a light source 3 by a halogen lamp 3 through a blue filter 4 and a half mirror 5, and by a halogen lamp 6. The light source 6 illuminates obliquely through the red filter 7. The reflected light from the printed wiring board 1 is wavelength-separated through a dichroic mirror 8 that selectively transmits blue, and the blue reflected light is imaged by a monochrome imaging camera unit 10 with a lens through a blue filter 9 and reflected in red. Light is imaged by a monochrome imaging camera unit 12 with a lens through a red filter 11. Each image is displayed on the image monitors 15 and 16 via the camera controllers 13 and 14.

  FIG. 2 is a diagram showing a defect image on the wiring pattern of the inspection object displayed on the image monitor 15 and the image monitor 16.

  The display screen 17 and the display screen 18 are display screens displayed on the image monitor 15 and the image monitor 16, respectively. The wiring pattern 19 includes a dishdown 20 and a fine short 21. The dishdown 20 is obliquely illuminated on the display screen 17 of the image monitor 15 that captures an image incident on the vertical epi-illumination. The images are simultaneously displayed on the display screen 18 of the image monitor 16 that captured the image.

  The wavelength of illumination from the light source is preferably an electromagnetic wave from 300 nanometers to 1200 nanometers.

As described above, according to the present embodiment, it is possible to display both fine short-circuit and dish-down defects simultaneously through the image monitor 15 and the image monitor 16.
[Example 2]
FIG. 3 is a diagram illustrating a configuration example of the wiring pattern inspection apparatus according to the present embodiment.

  The wiring pattern inspection apparatus includes a red LED ring light illumination 23, a blue LED illumination 24, a half mirror 25, a dichroic mirror 26, a blue filter 27, a lens 28, a CCD line sensor 29, a red filter 30, a lens 31, and a CCD line sensor 32. , Stage 33, motor 34, motor 35, motor drive device 36, motor drive device 37, numerical control device 38, DA converter 39, DA converter 40, image processing device 41, image processing device 42, defect determination circuit 43, defect determination A circuit 44 and a computer 45 are included.

  The ring light illumination 23 of the red LED is a light source that irradiates the inspection object as red light. The blue LED illumination 24 is a light source that irradiates the inspection object as blue light. The half mirror 25 vertically illuminates the light of the blue LED illumination 24. The dichroic mirror 26 selectively transmits blue light among the reflected light of the inspection object. The blue filter 27 transmits blue light. The lens 28 images the wavelength-separated blue light onto the CDD line sensor 29. The CCD line sensor 29 converts the image formed by the lens 28 into an electrical signal (image signal). The red filter 30 transmits red light. The lens 31 forms an image of the wavelength-separated red light on the CDD line sensor 32. The CCD line sensor 32 converts an image formed by the lens 31 into an electric signal (image signal). The position of the stage 33 is controlled by the numerical controller 38 in the X and Y directions. The motor 34 moves the stage 33 in the X direction. The motor 35 moves the stage 33 in the Y direction. The motor driving device 36 drives the motor 35. The motor driving device 37 drives the motor 34. The numerical controller 38 calculates the defect coordinates of the inspection object from the coordinate information of the stage 33. The DA converter 39 converts the image signal of the CCD line sensor 32 into a video signal. The DA converter 40 converts the image signal of the CCD line sensor 29 into a video signal. The image processing device 41 performs noise removal, image enhancement, and binarization image processing on the video signal from the DA converter 39. The image processing device 42 performs image processing for noise removal, image enhancement, and binarization on the video signal from the DA converter 40. The defect determination circuit 43 detects a defect in the wiring pattern such as a short circuit. The defect determination circuit 44 detects a defect in the wiring pattern such as dishdown.

  Next, an operation for detecting a defect in a wiring pattern by the wiring pattern inspection apparatus will be described.

  The wiring pattern of the printed circuit board 22 is vertically reflected by a red LED ring light illumination 23, a blue LED illumination 24 and a half mirror 25. The reflected light from the printed circuit board 22 is wavelength-separated via a dichroic mirror 26 that selectively transmits blue, and the blue reflected light is imaged on a CCD line sensor 29 via a blue filter 27 and a lens 28. On the other hand, the red reflected light is imaged on the CDD line sensor 32 via the red filter 30 and the lens 31. The stage 33 is numerically controlled by the numerical control device 38 in the X and Y directions by the motors 34 and 35 and the motor driving devices 36 and 37. By feeding the stage 33, a pattern image of the printed circuit board 22 can be obtained. Image signals from the CCD line sensors 29 and 32 are converted into video signals by the DA converters 39 and 40, and noise removal, image enhancement and binarization are performed by the image processing devices 41 and 42. At this time, the image processing device 41 that processes the signal from the blue epi-illumination sets the image enhancement and threshold value so that dishdown can be easily detected, and processes the signal from the red oblique illumination. 42 may be configured to set an image enhancement or a threshold value so that a fine short circuit is easily detected. Next, the image is sent to the defect determination circuits 43 and 44, and a defect in the wiring pattern is detected. At this time, the defect determination circuits 43 and 44 do not need to be the same, the defect determination circuit 43 has a defect extraction algorithm specialized for disconnection and chipping, and the defect determination circuit 43 has a defect extraction algorithm specialized for short and remaining copper. It is good also as a structure to have. The result of defect detection is sent to the computer 45 together with the information of the synchronization signal, and the defect coordinates are calculated from the stage coordinate information from the numerical controller 38 and stored.

  With the above configuration, the reflected light is separated by the blue filter 27 and the red filter 30 by changing the wavelength of the vertical illumination light and the oblique illumination light with respect to the printed circuit board 22, and the separated reflected light is imaged. The inspection result of the wiring pattern by two types of illumination can be obtained simultaneously by only one inspection.

  The present invention is not limited to the specifically disclosed embodiments, and various modifications and changes can be made without departing from the scope of the claims.

1 is a diagram illustrating a configuration example of a wiring pattern display device according to Embodiment 1. FIG. The figure which shows the defect image on the wiring pattern displayed on the image monitor. FIG. 6 is a diagram illustrating a configuration example of a wiring pattern inspection apparatus according to a second embodiment.

Explanation of symbols

1: printed wiring board, 2: wiring pattern, 3, 6: light source by halogen lamp, 4, 9: blue filter, 5: half mirror, 7, 11: red filter, 8: dichroic mirror, 10, 12: with lens Monochrome imaging camera unit, 13, 14: camera controller, 15, 16: image monitor, 17: screen of monitor 15, 18: screen of monitor 16, 19: wiring pattern, 20: dishdown, 21: fine short, 22: Printed circuit board, 23: Red LED ring light illumination, 24: Blue LED illumination, 25: Half mirror, 26: Dichroic mirror, 27: Blue filter, 28, 31: Lens, 29, 32: CCD line sensor, 30: Red Filter, 33: Stage, 38: Numerical control Location, 34, 35: Motor, 37: motor drive unit, 39, 40: DA converter, 41: image processing device, 43, 44: defect determination circuit, 45: computer.

Claims (5)

In a wiring pattern display device for irradiating a wiring board with light and displaying a wiring pattern formed on the wiring board by the reflected light,
A plurality of irradiation means for generating a plurality of lights having different wavelengths and irradiating the wiring board from a plurality of different predetermined directions;
Wavelength separation means for separating the wavelength of reflected light of the light irradiated to the wiring pattern from the irradiation means;
And a display unit that displays the wiring pattern according to the light having the wavelength separated by the wavelength separation means. The direction in which the irradiating means irradiates light is perpendicular or oblique to the wiring board,
The wiring pattern processing apparatus according to claim 1, wherein the wiring pattern is displayed in accordance with a direction in which the irradiation unit irradiates.   2. The wiring pattern processing apparatus according to claim 1, wherein the wavelength irradiated from the irradiation means is an electromagnetic wave from 300 nanometers to 1200 nanometers.   2. The wiring pattern processing apparatus according to claim 1, wherein the wavelength separation means is a filter for identifying a predetermined wavelength. In a wiring pattern inspection apparatus for irradiating a wiring board with light and detecting defects in the wiring pattern formed on the wiring board by the reflected light,
A plurality of irradiation means for generating a plurality of lights having different wavelengths and irradiating the wiring board from a plurality of different predetermined directions;
Wavelength separation means for separating the wavelength of reflected light of the light irradiated to the wiring pattern from the irradiation means;
Image processing means for subjecting the wiring pattern to image processing according to light having a wavelength separated by the wavelength separation means;
A wiring pattern processing apparatus comprising: defect determination means for determining whether or not the wiring pattern is defective based on image processing data of the wiring pattern subjected to image processing by the image processing means.

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