JP4827431B2 - Three-dimensional measuring device and substrate inspection device - Google Patents

Description

  The present invention relates to a three-dimensional measurement apparatus that measures a three-dimensional shape or the like of a measurement object and a substrate inspection apparatus that includes the three-dimensional measurement apparatus.

  Generally, a printed circuit board has an electrode pattern on a base substrate made of glass epoxy resin, and the surface is protected by a resist film. When an electronic component is mounted on the printed board, cream solder is first printed at a predetermined position that is not protected by a resist film on the electrode pattern. Next, the electronic component is temporarily fixed on the printed circuit board based on the viscosity of the cream solder. Thereafter, the printed circuit board is guided to a reflow furnace, and soldering is performed through a predetermined reflow process. In recent years, it is necessary to inspect the printed state of cream solder in the previous stage of being guided to a reflow furnace, and a three-dimensional measuring device is sometimes used for such inspection.

  In recent years, various so-called non-contact type three-dimensional measuring apparatuses using light have been proposed. For example, in a three-dimensional measurement apparatus using a phase shift method, an object to be measured (in this case, a printed circuit board) is irradiated with a light pattern having a striped light intensity distribution using visible light as a light source. Then, the object to be measured is imaged by a CCD camera, and the three-dimensional shape, particularly the height of the cream solder is measured by analyzing the phase difference of the stripes of the light pattern from the obtained image.

  However, the color around the printed portion of the cream solder on the printed circuit board (hereinafter referred to as the background region) varies. This is because various colors are used for the glass epoxy resin and the resist film. For example, in a relatively dark background area such as black, the contrast of image data based on imaging by a CCD camera is reduced. That is, the light / dark difference (luminance difference) of the light pattern is reduced in the image data. Therefore, it may be difficult to measure the height of the background area. Originally, in order to measure the height of the cream solder printed on the substrate with higher accuracy, it is desirable to take a height reference in the substrate. However, since the background area cannot be properly used as the height reference plane, there is a possibility that a height reference cannot be taken in the substrate.

As a technique for solving this, an apparatus has been devised that captures a plurality of images by switching imaging conditions, combines the plurality of images, and performs three-dimensional measurement using the combined image. In such a technique, for example, the imaging conditions are switched to 32 ways, a plurality of images are captured, and an image optimal for measurement is generated by combining them, and a desired measurement process is executed (for example, a patent) Reference 1).
JP 2002-357408 A

  However, in the above-described method, the imaging conditions are switched and a plurality of images are combined, which may complicate the apparatus and increase the cost. In addition, the composition processing is performed in order to generate a composite image including a series of cross-sectional contour partial images by extracting the partition area images satisfying the prescribed maximum luminance condition for each preset partition area and collecting the partition area images together. As a result, it takes time, and the time required for three-dimensional measurement is remarkably increased.

  The present invention has been made in order to solve the above-described problems, and the object of the present invention is to appropriately use a predetermined area of the measurement object as a height reference plane, and to simplify the cost. An object of the present invention is to provide a three-dimensional measuring apparatus and a substrate inspection apparatus that can reduce the time required for three-dimensional measurement while reducing the time.

  In the following, each means suitable for solving the above-mentioned purpose will be described in terms of items. In addition, the effect etc. peculiar to the means to respond | correspond as needed are added.

Means 1. 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
Imaging means for performing imaging based on irradiation of the light by the irradiation means;
The irradiation means can be used to irradiate the light with an irradiation intensity corresponding to the first measurement area, and to irradiate the light with an irradiation intensity corresponding to the second measurement area before or after the irradiation. Control means,
The three-dimensional measuring apparatus, wherein the imaging unit is configured to perform imaging for each irradiation by the control unit.

  In the three-dimensional measuring apparatus described in the means 1, the irradiating means can irradiate the measurement target with the light for three-dimensional measurement with the set irradiation intensity. The measurement object has a first measurement area to be inspected and a second measurement area to be a reference for height measurement of the first measurement area. The “irradiation intensity” is considered to be the luminance of a light source as an irradiation means. Moreover, it is possible that it is the brightness of the surface to be irradiated, that is, the illuminance. The same applies to the following means. Then, the imaging unit performs imaging based on light irradiation by the irradiation unit.

  Particularly in the means 1, the control means causes the irradiating means to irradiate the light with the irradiation intensity corresponding to the first measurement area, and irradiates the light with the irradiation intensity corresponding to the second measurement area before or after the irradiation. It is possible to make it. Then, imaging is performed by the imaging unit for each irradiation of light at each irradiation intensity by the control unit.

  For example, when imaging is performed for the purpose of measuring the first measurement area, the luminance is too high or too low in the second measurement area, or the difference between light and darkness (luminance difference) becomes small in the image data. There is. In that case, since the second measurement area serving as a reference for height measurement cannot be appropriately used, there is a possibility that a problem that the height reference cannot be adopted for the measurement object may occur.

  In this regard, according to the means 1, the first measurement area is irradiated with light at the irradiation intensity corresponding to the first measurement area, and the second measurement area is irradiated according to the second measurement area different from that. Light can be irradiated with intensity. Therefore, three-dimensional measurement based on imaging in accordance with the second measurement area is possible, and the second measurement area can be appropriately used as a measurement reference. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane.

  Further, if the imaging for the purpose of measuring the first measurement area and the imaging for the purpose of measuring the second measurement area are each performed once, three-dimensional measurement of the measurement object can be performed by a total of two times of imaging. It becomes possible. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

  The “irradiation intensity according to the first measurement area” and the “irradiation intensity according to the second measurement area” may be set in advance or may be separately measured and obtained each time. In addition, if the “irradiation intensity according to the first measurement area” is known, the “irradiation intensity according to the first measurement area” is set in advance, and imaging by “the irradiation intensity according to the first measurement area” is performed. "Irradiation intensity according to the second measurement area" may be obtained based on the video data.

  Further, if the measurement object is a printed circuit board, the first measurement area described above can be a solder area on which cream solder is printed. Further, the second measurement area may be a background area other than the solder area or an area provided in the background area. If the object to be measured is a printed circuit board, the background region may be a portion of an electrode pattern where cream solder is not printed, a portion of glass epoxy resin, or a portion of a resist film. . The same applies to the following means.

Mean 2. 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
Imaging means for performing imaging based on irradiation of the light by the irradiation means;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
Storage means for storing a correspondence relationship between the second measurement area and the irradiation intensity according to the second measurement area;
The irradiation unit is configured to irradiate the light with an irradiation intensity corresponding to the first measurement area, and before or after the irradiation, based on the correspondence stored in the storage unit, the second measurement area Control means for irradiating the light with a corresponding irradiation intensity,
The three-dimensional measuring apparatus, wherein the imaging unit is configured to perform imaging for each irradiation of the light at each irradiation intensity by the control unit.

  Also in the three-dimensional measurement apparatus described in the means 2, the irradiation means can irradiate the measurement target with the light for three-dimensional measurement with the set irradiation intensity. The measurement object has a first measurement area to be inspected and a second measurement area to be a reference for height measurement of the first measurement area. And an imaging means images based on irradiation of the light by an irradiation means, and three-dimensional measurement of a measurement target is performed by a three-dimensional calculating means.

  Here, particularly in the means 2, the correspondence between the second measurement area and the irradiation intensity corresponding to the second measurement area is stored in the storage means. Specifically, it is conceivable to store a correspondence relationship with the irradiation intensity based on the color of the second measurement area. That is, when the color of the second measurement area is darker than that of the first measurement area, the luminance difference on the image data is relatively small, and therefore a relatively large irradiation intensity is associated. On the other hand, when the color of the second measurement area is brighter than that of the first measurement area, the luminance value on the image data may be saturated, so a relatively small irradiation intensity is associated. Then, the control unit causes the irradiation unit to irradiate light with the irradiation intensity corresponding to the first measurement area, and before or after the irradiation, according to the second measurement area based on the correspondence relationship stored in the storage unit. Irradiate light with irradiation intensity. Here, imaging by the imaging unit is performed for each irradiation of light at each irradiation intensity by the control unit.

  According to the means 2, the correspondence relationship between the second measurement area and the irradiation intensity according to the second measurement area is stored, and separately from the light irradiation with the irradiation intensity according to the first measurement area, 2 Light is irradiated with an irradiation intensity corresponding to the measurement area. Therefore, three-dimensional measurement based on imaging in accordance with the second measurement area is possible, and the second measurement area can be appropriately used as a measurement reference. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane.

  Further, if the imaging for the purpose of measuring the second measurement area is performed only once before and after the imaging for the measurement of the first measurement area, the tertiary of the measurement object is obtained by the imaging twice. Original measurement becomes possible. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

Means 3. 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
Imaging means for performing imaging based on irradiation of the light by the irradiation means;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
Storage means for storing a correspondence relationship between the second measurement area and the irradiation intensity according to the second measurement area;
Setting means for setting an irradiation intensity according to the second measurement area based on the correspondence stored in the storage means;
Control means for causing the irradiation means to irradiate the light at an irradiation intensity corresponding to the first measurement area, and to irradiate the light at an irradiation intensity set by the setting means before or after the irradiation; With
The three-dimensional measuring apparatus, wherein the imaging unit is configured to perform imaging for each irradiation of the light at each irradiation intensity by the control unit.

  The three-dimensional measuring apparatus described in the means 3 is basically the same as the configuration described above. Therefore, the same effects as those of the three-dimensional measuring apparatus can be obtained.

  In particular, in the means 3, the irradiation intensity corresponding to the second measurement area is set by the setting means based on the correspondence stored in the storage means. Then, the control unit causes the irradiation unit to irradiate the light with the irradiation intensity corresponding to the first measurement area, and causes the light to be irradiated with the irradiation intensity set by the setting unit before or after the irradiation. Here, imaging by the imaging unit is performed for each irradiation of light at each irradiation intensity by the control unit. The setting means may be a means for automatically setting the irradiation intensity based on the correspondence stored in the storage means, or a means for the operator to manually set the irradiation intensity. With the latter configuration, the degree of freedom regarding the setting of the irradiation intensity is increased, and a wide range of irradiation intensity settings can be made using the operator's experience.

  As the configuration of the setting means in the configuration in which the operator manually sets the irradiation intensity, the following can be considered.

Means 4. In the three-dimensional measuring apparatus according to means 3,
Display means having a display screen for displaying information;
Input means for inputting information,
The setting means displays the correspondence on the display screen of the display means, and when the correspondence displayed on the display screen is selected via the input means, the setting is based on the selected correspondence. A three-dimensional measuring apparatus configured to set the irradiation intensity.

  According to the means 4, when the correspondence is displayed on the display screen of the display means and the correspondence displayed on the display screen is selected via the input means, the irradiation intensity is set based on the selected correspondence. Is done. Therefore, even when the operator manually sets the irradiation intensity, a relatively easy setting of the irradiation intensity is realized.

  The display means may be embodied as a display device having a display screen such as a CRT or a liquid crystal. Further, the input means may be embodied as a pointing device such as a mouse, or a touch panel integrated with a display screen. The same applies to the following means.

Means 5. In the three-dimensional measuring apparatus according to any one of means 1 to 4,
The three-dimensional measuring apparatus according to claim 1, wherein the irradiation intensity corresponding to the first measurement area is a predetermined irradiation intensity.

  For example, it is conceivable to set the irradiation intensity according to the first measurement area automatically or manually. However, for example, when the first measurement area is a solder area on which cream solder is printed, the first measurement area exhibits substantially the same color, and therefore the irradiation intensity corresponding to the first measurement area is naturally determined. Therefore, in such a case, as shown in the means 5, it is conceivable to adopt a predetermined irradiation intensity. In this way, simplification of the apparatus can be promoted, and the time required for three-dimensional measurement can be shortened.

Means 6. 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
Imaging means for performing imaging based on irradiation of the light by the irradiation means;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
Storage means for storing a correspondence relationship between the first measurement area and the irradiation intensity according to the first measurement area, and a correspondence relationship between the second measurement area and the irradiation intensity according to the second measurement area. When,
Setting means for setting a first irradiation intensity corresponding to the first measurement area and a second irradiation intensity corresponding to the second measurement area based on the correspondence stored in the storage means;
The irradiating means irradiates the light with the first irradiation intensity set by the setting means, and the light with the second irradiation intensity set by the setting means before or after the irradiation. Control means for irradiating
The three-dimensional measuring apparatus, wherein the imaging unit is configured to perform imaging for each irradiation of the light at each irradiation intensity by the control unit.

  Similarly to the above-described configuration, the three-dimensional measurement apparatus described in the means 6 can also irradiate the measurement object with light for three-dimensional measurement with a set irradiation intensity. The measurement object has a first measurement area to be inspected and a second measurement area to be a reference for height measurement of the first measurement area. And an imaging means images based on the irradiation of the light by an irradiation means, and the three-dimensional calculation means performs three-dimensional measurement of a measurement object.

  Here, in particular, in the means 6, the correspondence between the first measurement area and the irradiation intensity according to the first measurement area, and the correspondence between the second measurement area and the irradiation intensity according to the second measurement area are: It is stored in the storage means. Further, based on these correspondences, the setting means sets the first irradiation intensity corresponding to the first measurement area and the second irradiation intensity corresponding to the second measurement area. Then, the control means causes the irradiation means to irradiate light at the first irradiation intensity set by the setting means, and before or after the irradiation, emits light at the second irradiation intensity set by the setting means. Irradiate. Here, imaging by the imaging unit is performed for each irradiation of light at each irradiation intensity by the control unit.

  According to the means 6, not only the second irradiation intensity corresponding to the second measurement area but also the first irradiation intensity corresponding to the first measurement area is set by the setting means. Then, imaging is performed by irradiating light with the first and second irradiation intensities. Therefore, in addition to the effects described above, it is advantageous in that three-dimensional measurement in the first measurement area can be reliably performed.

Mean 7 In the three-dimensional measuring apparatus according to means 6,
Display means having a display screen for displaying information;
Input means for inputting information,
The setting means displays the correspondence on the display screen of the display means, and when the correspondence displayed on the display screen is selected via the input means, the setting is based on the selected correspondence. The three-dimensional measuring apparatus is configured to set an irradiation intensity according to the measurement area.

  According to the means 7, when the correspondence relation is displayed on the display screen of the display means and the correspondence relation displayed on the display screen is selected via the input means, the correspondence relation is selected according to the measurement area based on the selected correspondence relation. The irradiation intensity is set. Therefore, even when the operator manually sets the irradiation intensity, a relatively easy setting of the irradiation intensity is realized.

Means 8. In the three-dimensional measuring apparatus according to any one of means 1 to 7,
The three-dimensional measurement of the measurement object is configured to be performed by performing three-dimensional measurement of the first measurement area and three-dimensional measurement of the second measurement area based on separate imaging. 3D measuring device.

  According to the means 8, the three-dimensional measurement of the first measurement area and the three-dimensional measurement of the second measurement area are performed based on separate imaging, and the three-dimensional measurement of the measurement object is performed. That is, complicated processing such as image synthesis is not performed. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

Means 9. In the three-dimensional measurement apparatus according to any one of means 1 to 8,
The measurement object has a plurality of the second measurement areas,
The control means is configured to allow the irradiation means to irradiate the plurality of second measurement areas with the light with different irradiation intensities. .

  According to the means 9, it is possible to irradiate light with different irradiation intensities on the plurality of second measurement areas. In this way, although the number of times of imaging is three times or more, three-dimensional measurement of each second measurement area can be reliably performed, and each second measurement area can be appropriately used as a measurement reference. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane.

  By the way, when the 1st measurement area is a solder field where cream solder was printed, it is possible to adopt the following composition.

Means 10. 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
Imaging means for performing imaging based on irradiation of the light by the irradiation means;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
Irradiating the light with a first irradiation intensity corresponding to the first measurement area using the irradiation means, and determining whether or not three-dimensional measurement of the second measurement area is possible by imaging based on the irradiation; When it is determined that three-dimensional measurement is impossible, the first irradiation intensity is corrected according to the second measurement area, and the irradiation unit performs the irradiation with the corrected second irradiation intensity. And a control means for irradiating the three-dimensional measuring device.

  In the three-dimensional measurement apparatus described in the means 10, the irradiation means can irradiate the measurement target with the light for three-dimensional measurement with the set irradiation intensity. The measurement object has a first measurement area to be inspected and a second measurement area to be a reference for height measurement of the first measurement area. The “irradiation intensity” is considered to be the luminance of a light source as an irradiation means. Moreover, it is possible that it is the brightness of the surface to be irradiated, that is, the illuminance. The same applies to the following means. And an imaging means images based on the irradiation of the light by an irradiation means, and the three-dimensional calculation means performs three-dimensional measurement of a measurement object.

  Here, in particular, in the means 10, the control means causes the irradiation means to irradiate light with the first irradiation intensity corresponding to the first measurement area, and whether or not three-dimensional measurement of the second measurement area is possible by imaging based on the irradiation. If it is determined that the three-dimensional measurement is impossible, the first irradiation intensity is corrected according to the second measurement area, and the irradiation unit is irradiated with the light with the corrected second irradiation intensity. Irradiate.

  For example, when imaging is performed for the purpose of measuring the first measurement area, the luminance is too high or too low in the second measurement area, or the difference between light and darkness (luminance difference) becomes small in the image data. There is. In that case, since the second measurement area serving as a reference for height measurement cannot be appropriately used, there is a possibility that a problem that the height reference cannot be adopted for the measurement object may occur.

  In this regard, in the means 10, when the three-dimensional measurement of the second measurement area is impossible by imaging based on the irradiation with the first irradiation intensity, the first irradiation intensity is corrected according to the second measurement area, Light is irradiated with the second irradiation intensity. Therefore, according to imaging based on irradiation with the second irradiation intensity, three-dimensional measurement of the second measurement area can be reliably performed, and the second measurement area can be appropriately used as a measurement reference. On the other hand, when 3D measurement of the second measurement area is possible by imaging at the first irradiation intensity, 3D measurement of the second measurement area can be performed by the imaging, and the second measurement area is used as a measurement reference. It can be used properly. That is, in any case, the predetermined area of the measurement object can be appropriately used as the height reference plane.

  According to the means 10, depending on the case, even if correction is performed by one imaging, the imaging region is three-dimensionally measured by two imaging. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

  The technical idea in this configuration is based on the premise that the irradiation intensity for reliably performing the three-dimensional measurement of the first measurement area is known in advance. In other words, since the first imaging can surely perform the three-dimensional measurement of the first measurement area, the imaging with the first irradiation intensity is performed first, and the second irradiation intensity is used only in a specific case. The second imaging is to be performed. The same applies to the following configurations.

Means 11. 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
Imaging means for performing imaging based on irradiation of the light by the irradiation means;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
A first irradiation process in which the irradiation means is used to irradiate the light with a first irradiation intensity corresponding to the first measurement area, and three-dimensional measurement of the second measurement area is possible by imaging based on the first irradiation process. A determination process for determining whether or not the three-dimensional measurement is impossible in the determination process, a correction process for correcting the first irradiation intensity according to the second measurement area, and And a control unit capable of executing a second irradiation process for irradiating the light with the second irradiation intensity corrected by the correction process using an irradiation unit.

  Also in the three-dimensional measurement apparatus described in the means 11, the irradiation means can irradiate the measurement target with the light for three-dimensional measurement with the set irradiation intensity. The measurement object has a first measurement area to be inspected and a second measurement area to be a reference for height measurement of the first measurement area. And an imaging means images based on the irradiation of the light by an irradiation means, and the three-dimensional calculation means performs three-dimensional measurement of a measurement object.

  Here, in particular, in the means 11, the first irradiation process, the determination process, the correction process, and the second irradiation process can be executed by the control means. In the first irradiation process, the irradiation unit is irradiated with light at a first irradiation intensity corresponding to the first measurement area. In the determination process, it is determined whether or not three-dimensional measurement of the second measurement area is possible by imaging based on the first irradiation process. In the correction process, the first irradiation intensity is corrected when it is determined in the determination process that three-dimensional measurement is impossible. In the second irradiation process, the irradiation unit is irradiated with light at the second irradiation intensity corrected in the correction process.

  According to the means 11, when the three-dimensional measurement of the second measurement area is impossible by imaging based on the irradiation with the first irradiation intensity, the first irradiation intensity is corrected according to the second measurement area, and the first Light is irradiated with an irradiation intensity of 2. Therefore, according to imaging based on irradiation with the second irradiation intensity, three-dimensional measurement of the second measurement area can be reliably performed, and the second measurement area can be appropriately used as a measurement reference. On the other hand, when 3D measurement of the second measurement area is possible by imaging at the first irradiation intensity, 3D measurement of the second measurement area can be performed by the imaging, and the second measurement area is used as a measurement reference. It can be used properly. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane.

  Further, according to the means 11, depending on the case, even if correction is performed by one imaging, the measurement object is three-dimensionally measured by two imaging. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

Means 12. In the three-dimensional measuring apparatus according to means 10 or 11,
The three-dimensional calculation means performs the three-dimensional measurement of the first measurement area and the three-dimensional measurement of the second measurement area based on separate imaging when imaging is performed with the second irradiation intensity. Thus, the three-dimensional measuring apparatus is configured to perform three-dimensional measurement of the measurement object.

  According to the means 12, when the three-dimensional measurement of the measurement object is performed by two imaging, the three-dimensional measurement of the first measurement area and the three-dimensional measurement of the second measurement area are performed based on separate imaging, Three-dimensional measurement of the measurement object is performed. That is, complicated processing such as image synthesis is not performed. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

Means 13. In the three-dimensional measurement apparatus according to any one of means 10 to 12,
The determination as to whether or not three-dimensional measurement of the second measurement area is possible is made using luminance in a background region in image data obtained by imaging based on irradiation at the first irradiation intensity. Former measuring device.

  According to the means 13, the determination as to whether or not three-dimensional measurement of the second measurement area is possible is made by using the luminance in the background region in the image data obtained by imaging based on the irradiation with the first irradiation intensity. In this way, it is possible to easily determine whether or not three-dimensional measurement is possible, which contributes to simplification of the apparatus.

Means 14. In the three-dimensional measuring apparatus according to means 13,
The determination as to whether or not the three-dimensional measurement is possible is made using a difference between an average luminance value in the background area and a predetermined luminance target value.

  When the luminance in the image data is used to determine whether or not three-dimensional measurement is possible, it is considered to use a difference between the average luminance value in the background area and a predetermined luminance target value as shown in the means 14. It is done. For example, when the light to be irradiated is a striped pattern, it is known that the average luminance decreases as the difference in brightness decreases. Thus, it is conceivable to determine a target value in advance and use the difference from the target value. In this way, it is possible to easily determine whether or not three-dimensional measurement is possible, which contributes to simplification of the apparatus.

Means 15. In the three-dimensional measuring apparatus according to means 13 or 14,
The correction of the first irradiation intensity according to the second measurement area is performed based on a ratio between an average luminance value in the background area and a predetermined luminance target value. apparatus.

  According to the means 15, the correction of the first irradiation intensity corresponding to the second measurement area is performed based on the ratio between the average value of the luminance in the background region and the target value. For example, if the average value is ½ of the target value, the irradiation intensity is doubled. In this way, the irradiation intensity can be corrected with a relatively simple configuration, which contributes to simplification of the apparatus.

Means 16. In the three-dimensional measuring apparatus according to means 13 or 14,
Storage means for storing correction information for correcting the first irradiation intensity based on an average value of luminance in the background region;
The three-dimensional measurement apparatus according to claim 1, wherein the correction of the first irradiation intensity according to the second measurement area is performed based on correction information stored in the storage unit.

  According to the means 16, the correction of the first irradiation intensity corresponding to the second measurement area is performed based on the correction information stored in the storage means. Although it is possible to correct the irradiation intensity based on the ratio as described above, the irradiation intensity and the luminance of the image are not necessarily completely linearly proportional. Therefore, it is conceivable to prepare correction information for correcting the irradiation intensity based on the average value of the luminance in the background area, and to correct the irradiation intensity based on the correction information. In this way, the corrected second irradiation intensity becomes more appropriate, and the three-dimensional measurement of the second measurement area can be reliably executed by imaging based on the irradiation with the second irradiation intensity.

Means 17. In the three-dimensional measuring apparatus according to means 13 or 14,
Storage means for storing a correspondence relationship between the second measurement area and the irradiation intensity according to the second measurement area;
The three-dimensional measuring apparatus according to claim 1, wherein the correction of the irradiation intensity according to the second measurement area is performed based on the correspondence stored in the storage unit.

  According to the means 17, the correspondence relationship between the second measurement area and the irradiation intensity corresponding to the second measurement area is stored. Specifically, it is conceivable to store a correspondence relationship with the irradiation intensity based on the color of the second measurement area. That is, when the color of the second measurement area is darker than that of the first measurement area, the luminance difference on the image data is relatively small, and therefore a relatively large irradiation intensity is associated. On the other hand, when the color of the second measurement area is brighter than that of the first measurement area, the luminance value on the image data may be saturated, so a relatively small irradiation intensity is associated. Here, the correction of the irradiation intensity according to the second measurement area is performed based on the stored correspondence. In this way, the corrected second irradiation intensity becomes more appropriate, and the three-dimensional measurement of the second measurement area can be reliably executed by imaging based on the irradiation with the second irradiation intensity.

Means 18. In the three-dimensional measurement apparatus according to Means 17,
A three-dimensional measurement apparatus comprising: setting means for setting an irradiation intensity corresponding to the second measurement area based on the correspondence stored in the storage means.

  According to the means 18, the irradiation intensity corresponding to the second measurement area is set by the setting means based on the correspondence relationship stored in the storage means. Here, the setting means may be a means for automatically setting the irradiation intensity based on the correspondence stored in the storage means, or a means for the operator to manually set the irradiation intensity. With the latter configuration, the degree of freedom regarding the setting of the irradiation intensity is increased, and a wide range of irradiation intensity settings can be made using the operator's experience.

  In addition, as a specific configuration of the three-dimensional measuring apparatus including the setting unit, the display unit includes a display unit having a display screen for displaying information, and an input unit for inputting information. When the correspondence is displayed on the display screen of the display means and the correspondence displayed on the display screen is selected via the input means, the irradiation intensity is set based on the selected correspondence. It may be “to do”. In this way, even when the operator manually sets the irradiation intensity, a relatively easy setting of the irradiation intensity is realized. The display means may be embodied as a display device having a display screen such as a CRT or a liquid crystal. Further, the input means may be embodied as a pointing device such as a mouse, or a touch panel integrated with a display screen.

Means 19. In the three-dimensional measuring apparatus according to any one of means 1 to 18,
The three-dimensional measuring apparatus, wherein the second measurement area is black or gray that is relatively close to black.

  When the second measurement area is black or gray that is relatively close to black as shown in the means 19, in the image data obtained by imaging based on irradiation with the irradiation intensity corresponding to the first measurement area, the second measurement area image There is a high possibility that the difference in brightness (brightness difference) will be small. Therefore, in such a configuration, the effect of the present invention stands out.

Means 20. In the three-dimensional measuring apparatus according to any one of means 1 to 18,
The three-dimensional measuring apparatus, wherein the second measurement area is white or gray that is relatively close to white.

  When the second measurement area is white or gray that is relatively close to white as shown in the means 20, in the image data obtained by imaging based on the irradiation with the irradiation intensity corresponding to the first measurement area, the second measurement area image There is a high possibility that the brightness of the liquid crystal becomes too high and becomes saturated. Therefore, in such a configuration, the effect of the present invention stands out.

Means 21. In the three-dimensional measurement apparatus according to any one of means 1 to 20,
The measurement object is a printed circuit board on which an electrode pattern is formed with respect to a base substrate, the first measurement area is a solder region in which solder is printed on the electrode pattern, and the second measurement area is The resist pattern is provided in a background area other than the solder area and covers the electrode pattern, the base substrate, the electrode pattern, or a resist film that covers the base substrate, and is used for the inspection of the printed circuit board. A three-dimensional measuring device characterized in that

  In the means 21, the measurement object is a printed board on which an electrode pattern is formed on the base board. Here, the first measurement area is a solder region in which solder is printed on the electrode pattern. The second measurement area is provided in a background area other than the solder area, and specifically, an electrode pattern, a base substrate, a resist film that covers the electrode pattern, or a resist film area that covers the base substrate. ing.

  In this case, the electrode pattern, the base substrate, the resist film covering the electrode pattern, or the region of the resist film covering the base substrate can be appropriately used as a reference for height measurement. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane.

  Here, the “solder area on which the solder is printed” includes a so-called solder area including cream solder, a silver paste area, a conductive adhesive area, and a bump area. The same applies to the following means.

  Although the above has been described as an invention of a three-dimensional measurement apparatus, it can also be realized as an invention of the following three-dimensional measurement method.

Means 22. A measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area is imaged by irradiating light for three-dimensional measurement, A three-dimensional measurement method for performing three-dimensional measurement of a measurement object,
The three-dimensional measurement method characterized in that the light irradiation for the imaging is performed according to the following procedures (1) to (4).

  (1) The light is irradiated at a first irradiation intensity corresponding to the first measurement area.

  (2) It is determined whether or not three-dimensional measurement of the second measurement area is possible based on imaging at the first irradiation intensity.

  (3) When it is determined that three-dimensional measurement of the second measurement area is impossible, the first irradiation intensity is corrected according to the second measurement area.

  (4) The light is irradiated with the corrected second irradiation intensity.

  Even with such a three-dimensional measurement method, the same effects as those of the above-described three-dimensional measurement apparatus can be obtained. That is, the three-dimensional measurement of the second measurement area can be reliably executed based on the imaging with the second irradiation intensity, and the second measurement area can be appropriately used as a measurement reference. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane. In some cases, even when correction is performed by one imaging, the measurement object is three-dimensionally measured by two imaging, so that the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

  Furthermore, it can also be realized as an invention of an inspection apparatus.

  Means 23. The three-dimensional measurement device according to any one of means 1 to 21 is provided, or the three-dimensional measurement method according to means 22 is adopted, and the measurement object is further based on the result of three-dimensional measurement of the measurement object. An inspection apparatus comprising inspection means for inspecting an object.

  Even in such an inspection apparatus, the above-described effects are exhibited. A “substrate inspection apparatus” based on the configuration of the means 21 may be used. That is, as shown below.

Means 24. The three-dimensional measurement apparatus according to any one of means 1 to 20 is provided, or the three-dimensional measurement method according to means 22 is adopted, and the measurement object is further based on the result of three-dimensional measurement of the measurement object. Equipped with inspection means for inspecting objects,
The measurement object is a printed circuit board on which an electrode pattern is formed with respect to a base substrate, the first measurement area is a solder region in which solder is printed on the electrode pattern, and the second measurement area is A substrate inspection apparatus provided in a background region other than a solder region, the electrode pattern, the base substrate, a resist film covering the electrode pattern, or a resist film region covering the base substrate .

  Even in such a substrate inspection apparatus, the above-described effects are exhibited.

Hereinafter, embodiments will be described with reference to the drawings.
[First Embodiment] (However, Reference Example)
As shown in FIG. 2, the printed circuit board 1 has a flat plate shape (having a flat surface), and a base substrate 2 made of glass epoxy resin or the like is provided with an electrode pattern 3 made of copper foil. Further, cream solder 4 is printed on the predetermined electrode pattern 3. The area where the cream solder 4 is printed is referred to as a “solder area”. The portion other than the solder region is collectively referred to as a “background region”. The background region includes a region where the electrode pattern 3 is exposed (symbol A), a region where the base substrate 2 is exposed (symbol B), and the base substrate 2. A region where the resist film 5 is coated (symbol C) and a region where the resist film 5 is coated on the electrode pattern 3 (symbol D) are included. Note that the resist film 5 is coated on the surface of the printed circuit board 1 so that the cream solder 4 is not applied to portions other than the predetermined wiring portion.

  FIG. 1 is a schematic configuration diagram schematically showing a printing state inspection apparatus 8 including a three-dimensional measuring apparatus according to the present embodiment. As shown in the figure, the printing state inspection apparatus 8 includes a mounting table 9 for mounting the printed circuit board 1 and an “irradiation” for irradiating a predetermined light component pattern obliquely from above to the surface of the printed circuit board 1. Illuminating device 10 as "means", CCD camera 11 as "imaging means" for imaging the irradiated portion on the printed circuit board 1, and various controls, image processing, and arithmetic processing in the printing state inspection device 8 And a control device 12 for carrying out the above. In addition, the illuminating device 10 is comprised so that the said light component pattern can be irradiated with the brightness | luminance set.

  The mounting table 9 is provided with motors 15 and 16, and the motors 15 and 16 are driven and controlled by the control device 12, whereby the printed circuit board 1 mounted on the mounting table 9 is in an arbitrary direction. It can be slid in the (X-axis direction and Y-axis direction).

  Next, the electrical configuration of the control device 12 will be described.

  As shown in FIG. 3, the control device 12 includes a CPU and an input / output interface 21 that control the entire printing state inspection device 8, an input device 22 as an “input unit” configured by a keyboard, a mouse, or a touch panel. A display device 23 as a “display unit” having a display screen such as a CRT or a liquid crystal, an image data storage device 24 for storing image data based on image pickup by the CCD camera 11, and cream solder 4 based on image pickup by the CCD camera 11 A three-dimensional calculation device 25 as a “three-dimensional calculation means” for measuring the height and volume of the sample, an inspection result storage device 26 for storing the inspection result, and an illumination database 27. The illumination database 27 includes a solder table 27A indicating the correspondence between the solder area (type of cream solder 4) and the luminance of the illumination device 10 corresponding to the solder area, and the background area (type of printed circuit board 1) and accordingly. The board table 27B indicating the correspondence with the brightness of the lighting device 10 is stored. In this embodiment, as shown in FIG. 4 (a), the solder table 27A includes the manufacturer of the cream solder 4 printed in the solder area such as the company A, the company B, the company C, and the illumination corresponding to them. The correspondence relationship with the brightness of the device 10 is shown. Further, as shown in FIG. 4B, the board table 27B shows a correspondence relationship between the colors of the background regions such as green, blue, and black and the luminance of the illumination device 10 according to them. Yes. Each of these devices 22 to 27 is electrically connected to the CPU and the input / output interface 21.

  Next, luminance setting processing for setting the luminance of the lighting device 10 executed by the control device 12 will be described based on the flowchart of FIG. 5 and the explanatory diagrams of FIGS. 6 and 7. This brightness setting process is repeatedly executed by selecting and operating the “set” button displayed on the display screen of the display device 23. The selection operation of the “setting” button is performed via the input device 22. For example, the selection operation is performed with a pointing device such as a mouse, or the selection operation is performed with a touch panel integrated with the display device 23. As realized.

  In the first step (hereinafter, the step is simply indicated by symbol S) 100, it is determined whether or not the type of the printed circuit board 1 to be inspected has been input. In the printed circuit board 1, it is assumed that an inspection area or the like is set for each type specified here. If it is determined that a product type has been input (S100: YES), product type information is displayed in S110, and the process proceeds to S120. On the other hand, when it is determined that the product type has not been input (S100: NO), the following process is not executed and the brightness setting process is temporarily terminated.

  A display example of product type information in S110 is shown in FIG. Here, for example, the case where the product type H is selected is shown. Specifically, a window W1 is displayed. This window W1 is composed of windows W2 and W3. The window W2 displays solder area information, and the window W3 displays background area information. The entire images PG1, PG2 of the printed circuit board 1 are displayed in both windows W2, W3. The whole images PG1 and PG2 are prepared in advance. Of course, the entire images PG1 and PG2 may be acquired based on the imaging by the CCD camera 11.

  The solder image PG1 displayed in the window W2 is a solder area on which the cream solder 4 is printed, and an inspection target area 31 (an oblique line is applied as a “first measurement area” to be inspected). (Shown area) is displayed. On the other hand, the background image PG2 displayed in the window W3 is a part of the background area, and is a measurement reference area 32 (shown with diagonal lines) as a “second measurement area” serving as a reference for height measurement. Area) is displayed. The window W2 displays a solder luminance input field 33, and the window W3 displays a background luminance input field 34. In these input fields 33 and 34, the luminance values may be displayed by default, or in the stage of S110, the input fields 33 and 34 may be displayed blank.

  Returning to the description of FIG. 5, in S120, it is determined whether or not the solder luminance input field 33 is selected. The selection of the solder luminance input field 33 is performed by a selection operation via the input device 22. That is, similarly to the above-described “setting” button selection operation, for example, a selection operation may be performed using a pointing device such as a mouse, or a selection operation may be performed using a touch panel integrated with the display device 23. The same applies to the selection operation on the display screen. If it is determined that the input field 33 is selected (S120: YES), a selection list (which will be described later) is displayed in S130, and the process proceeds to S140. On the other hand, when it is determined that the input field 33 is not selected (S120: NO), the process proceeds to S160.

  In S140, it is determined whether a luminance value is selected from the selection list. If it is determined that a luminance value has been selected (S140: YES), a solder luminance setting process is performed in S150, and the process proceeds to S160. On the other hand, this determination process is repeated until the luminance value is not selected (S140: NO). Of course, if no selection is made even after a predetermined time has elapsed, the processing may be terminated, or a warning or the like may be given (the same applies to S180).

  In S160, it is determined whether or not the background luminance input field 34 has been selected. The selection of the background luminance input field 34 is performed by a selection operation via the input device 22. If it is determined that the input field 34 has been selected (S160: YES), a selection list (to be described later) is displayed in S170, and the process proceeds to S180. On the other hand, when it is determined that the input field 34 is not selected (S160: NO), the process proceeds to S200.

  In S180, it is determined whether a luminance value is selected from the selection list. If it is determined that a luminance value has been selected (S180: YES), background luminance setting processing is performed in S190, and the process proceeds to S200. On the other hand, this determination process is repeated until the luminance value is not selected (S180: NO).

  In S200, it is determined whether or not there is an end instruction. This end instruction is given by selecting an “end” button on a screen (not shown). If it is determined that an end instruction has been given (S200: YES), the brightness setting process is ended. On the other hand, if it is determined that there is no termination instruction (S200: NO), the processing from S120 is repeated.

  Next, the selection and setting of brightness values (S120 to 190) described above will be described with specific examples. Here, background luminance selection and setting (S160 to S190) will be described, but solder luminance selection and setting (S120 to 150) is the same.

  The description will be made on the premise of the information display of the printed circuit board 1 of the type H shown in FIG. The display of the selection list in S170 is performed, for example, in the form shown in FIG. That is, when the background luminance input field 34 is selected (S160: YES), a new window W4 is displayed below the input field 34. The content of the displayed selection list is the correspondence between the color and the brightness in the substrate table shown in FIG. When a luminance value (shown by a black triangle or the like in the figure) in the selection list is selected (S180: YES), the luminance value is set (S190), and the background luminance input field 34 is set. Is displayed. In S180, the luminance value is selected. However, the substrate type (color) indicated as “green”, “blue”, “black”, or the like may be selected, or these luminance values may be selected. Alternatively, either one of the substrate types may be selected.

  When the inspection start is instructed after the solder luminance and the background luminance are set in this way, the lighting device 10 is turned on by the CPU and the input / output interface 21 shown in FIG. Then, a predetermined light component pattern is irradiated on the surface of the printed circuit board 1 obliquely from above. Then, the CCD camera 11 captures an image of the irradiated portion for each luminance by a control signal from the CPU and the input / output interface 21. Image data based on imaging by the CCD camera 11 is stored in the image data storage device 24.

  Then, based on the image data obtained by the irradiation with the brightness for the solder by the control signal from the CPU and the input / output interface 21, the three-dimensional arithmetic device 25 performs the three-dimensional inspection of the inspection target region 31 of the cream solder 4 shown in FIG. Perform measurements (height measurement, volume measurement, etc.). Further, based on the image data obtained by the irradiation with the background luminance, the three-dimensional arithmetic device 25 performs three-dimensional measurement (reference height measurement) of the measurement reference region 32 of the printed board 1 shown in FIG. Thereby, three-dimensional measurement of the printed circuit board 1 is performed. Specifically, the height and volume of the cream solder 4 in the inspection target area 33 are measured using the measurement reference area 32 as a height reference plane. That is, in the present embodiment, the three-dimensional measurement of the printed circuit board 1 can be performed by two imaging operations. In this embodiment, the phase shift method is adopted for three-dimensional measurement.

  Based on this measured value, the CPU and the input / output interface 21 inspect the printing state of the cream solder 4, determine whether it is good or bad, and store the inspection result in the inspection result storage device 26. The printed circuit board 1 determined to be defective is discharged by a discharge mechanism (not shown).

  As described above in detail, in the present embodiment, the correspondence relationship between the background region (measurement reference region 32) and the luminance of the illumination device 10 corresponding thereto is stored in the illumination database 27 as the substrate table 27B. In order to perform three-dimensional measurement of the measurement reference region 32 based on the substrate table 27B, the luminance (background luminance) of the illumination device 10 corresponding to the background region can be set. Under such a configuration, three-dimensional measurement of the measurement reference region 32 of the printed circuit board 1 is performed based on image data obtained by irradiation with background luminance. As a result, the three-dimensional measurement of the measurement reference region 32 can be reliably performed, and the measurement reference region 32 can be appropriately used as a measurement reference for the inspection target region 31. That is, the predetermined area of the measurement object can be appropriately used as the height reference plane. In particular, the substrate table 27B of FIG. 4B is also provided with a luminance corresponding to the case where the substrate type (substrate color) is “black”. This is because, when the measurement reference region 32 (background region) is black or gray that is relatively close to black, in the image data based on the imaging with the luminance according to the inspection target region 31, the brightness and darkness in the measurement reference region 32 This is because there is a high possibility that the difference (luminance difference) becomes small. Therefore, according to the present embodiment, when the measurement reference area 32 is black or gray that is relatively close to black, the effect is conspicuous.

  In the present embodiment, the correspondence between the solder area (inspection area 31) and the luminance of the illumination device 10 corresponding to the solder area is stored in the illumination database 27 as a solder table 27A. Based on the solder table 27A, the luminance (solder luminance) of the illumination device 10 corresponding to the solder area can be set in order to perform the three-dimensional measurement of the inspection target area 31. Under such a configuration, three-dimensional measurement of the measurement reference region 32 of the printed circuit board 1 is performed based on image data obtained by irradiation with soldering luminance. As a result, the three-dimensional measurement of the inspection target region 31 can be reliably performed.

  At this time, since the imaging for the measurement of the measurement reference area 32 is performed only once before and after the imaging for the measurement of the inspection target area 31, the three-dimensional measurement of the printed circuit board 1 is performed by the imaging twice. Is possible. As a result, the three-dimensional measuring apparatus can be simplified and the cost can be reduced. As a result, simplification and cost reduction of the printing state inspection device 8 are realized. In addition, the time required for three-dimensional measurement can be shortened.

  Furthermore, in the present embodiment, the three-dimensional measurement of the inspection target region 31 and the three-dimensional measurement of the measurement reference region 32 are performed based on separate imaging (imaging with solder luminance and imaging with background luminance). Then, three-dimensional measurement of the printed circuit board 1 is performed. That is, complicated processing such as image synthesis is not performed. Therefore, also in this respect, simplification and cost reduction of the apparatus are realized.

  In the present embodiment, the correspondence shown in the solder table 27A is displayed as a selection list (S130 in FIG. 5), and the brightness for solder is set by the selection operation by the operator (S140: YES) ( S150). Further, the correspondence shown in the substrate table 27B is displayed as a selection list (S170), and the background brightness is set (S190) by the selection operation by the operator (S180: YES). Since manual setting can be performed in this way, the degree of freedom regarding luminance setting is increased, and a wide range of luminance settings can be made using the operator's experience. In addition, a selection list is displayed on the display screen of the display device 23 (see FIG. 7), and the luminance value is selected by a selection operation via the input device 22, so that it is relatively Easy brightness setting is realized.

  In the embodiment described above, for example, a part of the configuration can be appropriately changed as follows. Of course, other modifications not exemplified below are also possible.

  (A) In the first embodiment, the solder table 27A having different brightness is stored for each manufacturer. However, the color of the solder area (area where the cream solder 4 is printed) is relatively stable. If there is, the solder table 27A may be omitted. That is, paying attention to the fact that there is no significant difference among the manufacturers, it is possible to employ a configuration in which the illumination device 10 is turned on with a predetermined luminance when imaging for the purpose of measuring the inspection target region 31.

  (B) In the first embodiment, the same (unique) background luminance is set for a plurality of measurement reference regions 32 (background regions), and imaging is performed based on irradiation of the illumination device 10 with the background luminance. It is carried out.

  On the other hand, it is good also as a structure which images the some measurement reference area | region 32 by irradiation with different brightness | luminance. This is because the plurality of measurement reference regions 32 are not necessarily the same color. Therefore, as shown in FIG. 8, in the display of product type information, symbols such as A to E are displayed corresponding to each measurement reference region 32, and the background luminance can be set for each measurement reference region 32. Also good. For example, the input field 35 is prepared so as to correspond to the symbol displayed on the image PG2 of the printed circuit board 1.

  In this way, although the number of times of imaging is three or more, the three-dimensional measurement of each measurement reference region 32 can be reliably performed, and each measurement reference region 32 can be appropriately used as a measurement reference. That is, the background area of the printed circuit board 1 can be appropriately used as the height reference plane.

  (C) As described above, the effect is conspicuous when the measurement reference region 32 (background region) is black or gray that is relatively close to black. However, the measurement reference region 32 (background region) is white or relatively close to white. In the case of gray, the luminance in the measurement reference region 32 (background region) becomes too high in the image data obtained by imaging with the irradiation intensity corresponding to the inspection target region 31 (solder region) and becomes saturated. There is a high risk. Therefore, if the substrate table 27B has a brightness corresponding to the case where the substrate type (substrate color) is “white”, the measurement reference region 32 (background region) is white or gray that is relatively close to white. If this is the case, the effect is conspicuous.

  (D) In the above-described embodiment, the present invention is embodied when measuring the height or the like of the cream solder 4 printed on the printed circuit board 1, but it can also be applied to an inspection apparatus such as a wafer substrate or a mounting substrate. For example, in the case of a wafer substrate, the surface of the oxide film can be used as the reference height, and the height, shape, volume, etc. of the solder bumps can be calculated.

  (E) In the above embodiment, the phase shift method is adopted as the three-dimensional measurement method. However, the light cutting method, the moire method, the focusing method, the confocal method, the spatial code method, and the lattice fringe projection method are also used. Various three-dimensional measurement methods such as these can also be adopted.

Next, a second embodiment will be described.
[Second Embodiment]
As shown in FIG. 2, the printed circuit board 1 has a flat plate shape (having a flat surface), and a base substrate 2 made of glass epoxy resin or the like is provided with an electrode pattern 3 made of copper foil. Further, cream solder 4 is printed on the predetermined electrode pattern 3. The area where the cream solder 4 is printed is referred to as a “solder area”. The portion other than the solder region is collectively referred to as a “background region”. The background region includes a region where the electrode pattern 3 is exposed (symbol A), a region where the base substrate 2 is exposed (symbol B), and the base substrate 2. A region where the resist film 5 is coated (symbol C) and a region where the resist film 5 is coated on the electrode pattern 3 (symbol D) are included. Note that the resist film 5 is coated on the surface of the printed circuit board 1 so that the cream solder 4 is not applied to portions other than the predetermined wiring portion.

  FIG. 1 is a schematic configuration diagram schematically showing a printing state inspection apparatus 8 including a three-dimensional measuring apparatus according to the present embodiment. As shown in the figure, the printing state inspection apparatus 8 includes a mounting table 9 for mounting the printed circuit board 1 and an “irradiation” for irradiating a predetermined light component pattern obliquely from above to the surface of the printed circuit board 1. Illuminating device 10 as "means", CCD camera 11 as "imaging means" for imaging the irradiated portion on the printed circuit board 1, and various controls, image processing, and arithmetic processing in the printing state inspection device 8 And a control device 12 for carrying out the above. In addition, the illuminating device 10 is comprised so that the said light component pattern can be irradiated with the brightness | luminance set.

  The mounting table 9 is provided with motors 15 and 16, and the motors 15 and 16 are driven and controlled by the control device 12, whereby the printed circuit board 1 mounted on the mounting table 9 is in an arbitrary direction. It can be slid in the (X-axis direction and Y-axis direction).

  Next, the electrical configuration of the control device 12 will be described.

  As shown in FIG. 3, the control device 12 includes a CPU and an input / output interface 21 as a “control unit” that controls the entire printing state inspection device 8, an input device 22 including a keyboard and a mouse, or a touch panel, A display device 23 having a display screen such as a CRT or a liquid crystal, an image data storage device 24 for storing image data based on the image captured by the CCD camera 11, and measuring the height and volume of the cream solder 4 based on the image captured by the CCD camera 11. A three-dimensional calculation device 25 as a “three-dimensional calculation means” for performing the above and an inspection result storage device 26 for storing the inspection result. Each of these devices 22 to 27 is electrically connected to the CPU and the input / output interface 21.

  By the way, an inspection area or the like is set for each type of printed circuit board 1 to be inspected. For example, FIG. 10 illustrates product type information of the printed circuit board 1 of the product type H. Such product type information is obtained by selecting a “product type display” button displayed on the display screen of the display device 23 and inputting the product type. The selection operation of the “product type” button is performed via the input device 22. For example, the selection operation is performed with a pointing device such as a mouse, or the selection operation is performed with a touch panel integrated with the display device 23. Realized as a configuration.

  As shown in FIG. 10, a window W1 is displayed in the display of product type information. This window W1 is composed of windows W2 and W3. The window W2 displays solder area information, and the window W3 displays background area information. The entire images PG1, PG2 of the printed circuit board 1 are displayed in both windows W2, W3. The whole images PG1 and PG2 are prepared in advance. Of course, the entire images PG1 and PG2 may be acquired based on the imaging by the CCD camera 11.

  The solder image PG1 displayed in the window W2 is a solder area on which the cream solder 4 is printed, and an inspection target area 31 (an oblique line is applied as a “first measurement area” to be inspected). Are displayed). On the other hand, the background image PG2 displayed in the window W3 is a background area, and a measurement reference area 32 (area shown by hatching) as a “second measurement area” that serves as a reference for height measurement. Is displayed.

  An inspection visual field is set in advance on the printed circuit board 1, and the printed circuit board 1 placed on the mounting table 9 is slid in an arbitrary direction (X-axis direction and Y-axis direction) according to the inspection visual field. For each inspection field of view, light pattern irradiation by the illumination device 10 and imaging by the CCD camera 11 are performed, and the printed state of the cream solder 4 in the inspection object region 31 is inspected. At this time, the inspection reference area 32 is used as a height reference plane.

  Next, imaging processing for each set inspection visual field will be described based on the flowchart of FIG. This imaging process is executed by the CPU and input / output interface 21.

  In the first step (hereinafter, the step is simply indicated by symbol S) 200, the luminance of the lighting device 10 is set in accordance with the cream solder 4. This luminance is predetermined as the luminance for solder.

  In subsequent S210, the illumination device 10 is turned on by the CPU and the input / output interface 21 so that the set luminance (soldering luminance) is obtained, and a predetermined light component pattern is irradiated obliquely from above to the surface of the printed circuit board 1. The Then, the CCD camera 11 captures an image of the irradiated portion by a control signal from the CPU and the input / output interface 21. Image data based on imaging by the CCD camera 11 is stored in the image data storage device 24.

  In the next S220, the average luminance of the background area is calculated based on the image data captured in S210.

  In subsequent S230, it is determined whether or not the difference between the target luminance of the background area and the average luminance calculated in S220 is equal to or greater than a threshold value. If it is determined that the difference is greater than or equal to the threshold value (S230: YES), the process proceeds to S240. On the other hand, when the difference is below the threshold value (S230: NO), the subsequent processing is not executed and the present imaging processing is terminated.

  In S240, where the difference is determined to be greater than or equal to the threshold value, the luminance is corrected. Specifically, the luminance of the lighting device 10 is corrected and set based on the ratio between the average luminance and the target luminance calculated in S220. That is, the luminance for solder is corrected and the luminance for background is set.

  In S250, the illumination device 10 is turned on by the CPU and the input / output interface 21 so that the corrected luminance (background luminance) is obtained, and a predetermined light component pattern is irradiated obliquely from above to the surface of the printed circuit board 1. . Then, the CCD camera 11 captures an image of the irradiated portion by a control signal from the CPU and the input / output interface 21. Image data based on imaging by the CCD camera 11 is stored in the image data storage device 24.

  The above imaging process is a process executed by the “control unit”. Specifically, the illumination process in S210 corresponds to the “first irradiation process”, the process in S230 corresponds to the “determination process”, and the process in S240. The correction process corresponds to the “correction process”, and the illumination process in S250 corresponds to the “second irradiation process”.

  In order to facilitate understanding of the above imaging processing, a specific example will be described.

  FIG. 12 schematically shows the luminance of the light pattern in the background area as a graph. The ideal luminance for performing the three-dimensional measurement of the background region (measurement reference region 32) is indicated by a two-dot chain line at the top of the graph. When a striped light pattern is irradiated, a sine curve having a certain amplitude is desirable. However, when imaging is performed with luminance matching the solder area (inspection target area 31), a sine curve with a small amplitude as indicated by a solid line at the bottom of the graph may occur when the background area is a relatively dark color. is there. That is, the difference in brightness (brightness difference) becomes small.

  Therefore, in the above-described imaging process, the average luminance of the background area is calculated (S2230 in FIG. 11), and it is determined whether or not the difference from the target luminance is greater than or equal to the threshold (S230). If this is the case (S230: YES), the luminance for solder is corrected and the luminance for background is set (S240). In FIG. 12, the average luminance value of the background region, that is, the average value N of the sine curve at the bottom of the graph is calculated (S220), and the difference D from the target value M, which is a predetermined ideal average luminance value. Is greater than or equal to a threshold value (S230). If it is equal to or greater than the threshold value (S230: YES), the luminance for solder is corrected based on the ratio between the target value M and the average value N to set the background luminance. More specifically, the brightness for background is set by multiplying the brightness for solder by (M / N).

  Then, when illumination / imaging is performed at the background luminance, the three-dimensional arithmetic device 25 is based on the image data obtained by the irradiation at the background luminance by the control signal from the CPU and the input / output interface 21. Three-dimensional measurement of the measurement reference region 32 of the printed circuit board 1 shown in FIG. 10 is performed. Further, based on the image data obtained by irradiation with the soldering luminance, the three-dimensional arithmetic device 25 performs three-dimensional measurement of the inspection target region 31 of the cream solder 4 shown in FIG. Thereby, three-dimensional measurement of the printed circuit board 1 is performed. Specifically, the height and volume of the cream solder 4 in the inspection target area 33 are measured using the measurement reference area 32 as a height reference plane.

  On the other hand, when illumination / imaging at the background luminance is not performed, the three-dimensional arithmetic device 25 is based on the image data obtained by the irradiation at the solder luminance by the control signal from the CPU and the input / output interface 21. Three-dimensional measurement is performed on the inspection target region 31 and the measurement reference region 32 of the printed circuit board 1 shown in FIG. Thereby, three-dimensional measurement of the printed circuit board 1 is performed. Specifically, the height and volume of the cream solder 4 in the inspection target area 33 are measured using the measurement reference area 32 as a height reference plane.

  In this embodiment, the phase shift method is adopted for three-dimensional measurement.

  Based on this measurement value, the CPU and the input / output interface 21 inspect the printing state of the cream solder 4, determine whether it is good or bad, and store the inspection result in the inspection result storage device 26. The printed circuit board 1 determined to be defective here is discharged by a discharge mechanism (not shown).

  As described in detail above, in the present embodiment, the illumination device 10 is first turned on with the brightness for solder matched to the solder area (inspection target area 31), and imaging is performed (S200 and S210 in FIG. 11). Under the assumption that the color of the cream solder 4 is not so different depending on the manufacturer, the three-dimensional measurement of the inspection target region 31 can be surely performed based on the first imaging. Based on this first imaging, the average value of the luminance of the background area is calculated (S220). If the difference from the luminance target value is greater than or equal to the threshold (S230: YES), The luminance for solder is corrected using the ratio to set the luminance for background (S240). When the background luminance is set, the lighting device 10 is turned on with the background luminance, and the second imaging is performed (S250). Therefore, based on this second imaging, the three-dimensional measurement of the measurement reference region 32 can be reliably performed. As a result, the three-dimensional measurement of the measurement reference region 32 can be surely executed, and the predetermined region of the measurement object can be appropriately used as the height reference plane. In addition, depending on the case, even when correction is performed by one imaging, three-dimensional measurement of the imaging region is performed by two imaging. Therefore, the apparatus can be simplified and the cost can be reduced. In addition, the time required for three-dimensional measurement can be shortened.

  Further, in the present embodiment, when imaging is performed twice, the three-dimensional measurement of the inspection target region 31 and the three-dimensional measurement of the measurement reference region 32 are performed separately (first imaging with the luminance for solder, background 3D measurement of the printed circuit board 1 (inspection field of view). That is, complicated processing such as image synthesis is not performed. Therefore, also in this respect, simplification and cost reduction of the apparatus are realized.

  Furthermore, in this embodiment, the average luminance of the background area is calculated (S2230 in FIG. 11), and it is determined whether the difference from the target luminance is equal to or greater than a threshold (S230). (S230: YES), the luminance for solder is corrected and the luminance for background is set (S240). As described above, since the determination process is performed using the luminance of the background area and the difference between the target values of the luminance, the determination process can be simplified. Further, in the correction process, correction is performed based on the ratio between the average value of the background luminance and the target value. Therefore, the correction process can be simplified. Also from these things, simplification and cost reduction of an apparatus are implement | achieved.

  In addition, when the measurement reference region 32 (background region) is black or gray that is relatively close to black, in the image data based on imaging with luminance corresponding to the inspection target region 31, a difference in brightness (luminance difference) in the background region. ) Is likely to be small. Even in such a case, since the three-dimensional measurement of the measurement reference region 32 can be performed by correcting the ratio between the average value of the actual luminance and the target value, the measurement reference region 32 is black or relatively close to black. If it is gray, the effect is noticeable.

  In the embodiment described above, for example, a part of the configuration can be appropriately changed as follows. Of course, other modifications not exemplified below are also possible.

  (A) In the second embodiment, the luminance for solder is corrected by the ratio between the average value of the luminance of the background area in the image data and the target value. In this way, the luminance for solder is corrected with a relatively simple calculation formula, but the irradiation intensity and the luminance of the image data are not completely linearly proportional.

  Therefore, the database 28 as “storage means” as shown by a two-dot chain line in FIG. 9 may be provided, and correction information may be stored therein. The correction information may be, for example, a correction magnification for solder luminance in accordance with the average luminance value of the background area. When it is determined that the three-dimensional measurement of the measurement reference region 32 is impossible based on the first imaging, the luminance for solder is corrected with reference to the correction information to set the luminance for background. In this way, the set background luminance becomes more appropriate, and the three-dimensional measurement of the second measurement area can be reliably executed by imaging with the background luminance.

  Similarly, the database 28 as “storage means” may be provided, and correspondence information may be stored therein. The correspondence information indicates the correspondence between the measurement reference region 32 and the luminance corresponding to the measurement reference region 32. If it is determined that the three-dimensional measurement of the measurement reference region 32 is impossible based on the first imaging, the background luminance corresponding to the measurement reference region 32 is set with reference to the correspondence information. In this way, the set background luminance becomes more appropriate, and the three-dimensional measurement of the second measurement area can be reliably executed by imaging with the background luminance.

  (B) As described above, the effect is conspicuous when the measurement reference region 32 (background region) is black or gray that is relatively close to black. However, the measurement reference region 32 (background region) is white or relatively close to white. In the case of gray, the luminance in the measurement reference region 32 (background region) becomes too high in the image data obtained by imaging with the irradiation intensity corresponding to the inspection target region 31 (solder region) and becomes saturated. There is a high risk. Therefore, the effect is conspicuous even when the measurement reference region 32 (background region) is white or gray that is relatively close to white.

  (C) In the above-described embodiment, the embodiment is implemented when measuring the height or the like of the cream solder 4 printed and formed on the printed circuit board 1, but the present invention can be applied to an inspection apparatus such as a wafer substrate or a mounting substrate. For example, in the case of a wafer substrate, the surface of the oxide film can be used as the reference height, and the height, shape, volume, etc. of the solder bumps can be calculated.

  (D) In the above embodiment, the phase shift method is adopted as the three-dimensional measurement method. However, the light cutting method, the moire method, the focusing method, the confocal method, the spatial code method, and the lattice fringe projection method are also used. Various three-dimensional measurement methods such as these can also be adopted.

It is a schematic perspective view which shows typically the printing condition inspection apparatus in embodiment. It is sectional drawing of a printed circuit board. It is a schematic block diagram of the printing condition inspection apparatus of a 1st embodiment. It is explanatory drawing which shows the table for solder | solder, and the table for board | substrates. It is a flowchart which shows a luminance setting process. It is explanatory drawing which illustrates the display screen of kind information. It is explanatory drawing which illustrates selection of the brightness | luminance on the display screen of kind information. It is explanatory drawing which illustrates the display screen of the kind information in another embodiment. It is a schematic block diagram of the printing condition inspection apparatus of 2nd Embodiment. It is explanatory drawing which illustrates the display screen of kind information. It is a flowchart which shows an imaging process. It is explanatory drawing for showing correction | amendment of a brightness | luminance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Printed circuit board, 2 ... Glass epoxy resin, 3 ... Electrode pattern, 4 ... Cream solder, 5 ... Resist film, 8 ... Print condition inspection apparatus, 9 ... Mounting stage, 10 ... Illumination device, 11 ... CCD camera, 12 ... Control device 15, 16 ... motor, 21 ... input / output interface, 22 ... input device, 23 ... display device, 24 ... image data storage device, 25 ... three-dimensional arithmetic device, 26 ... inspection result storage device, 27 ... for illumination Database: 27A ... Solder table, 27B ... Substrate table, 28 ... Database, 31 ... Inspection target area, 32 ... Measurement reference area, 33, 34, 35 ... Input field.

Claims (5)

3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
An imaging unit that performs imaging of the measurement object so as to include a first measurement area and a second measurement area based on the irradiation of the light by the irradiation unit;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
Irradiating the light with a first irradiation intensity corresponding to the first measurement area using the irradiation means, and calculating an average luminance of the second measurement area based on an imaging result by the imaging means based on the irradiation ; Determine whether the difference between the average brightness and the target brightness is greater than or equal to a predetermined threshold,
When the difference is greater than or equal to a predetermined threshold value , the first irradiation intensity is corrected based on the imaging result by the imaging unit based on the irradiation of the light with the irradiation intensity corresponding to the first measurement area. And setting a second irradiation intensity corresponding to the second measurement area, and performing a process of irradiating the light with the set second irradiation intensity by using the irradiation means ,
And a control unit that does not execute the process when the difference is less than a predetermined threshold value . 3D measurement light is irradiated with a set irradiation intensity to a measurement object having a first measurement area to be inspected and a second measurement area to be a height measurement reference of the first measurement area. Possible irradiation means;
An imaging unit that performs imaging of the measurement object so as to include a first measurement area and a second measurement area based on the irradiation of the light by the irradiation unit;
Three-dimensional calculation means for performing three-dimensional measurement of the measurement object based on imaging by the imaging means;
A first irradiation process for irradiating the light with a first irradiation intensity corresponding to the first measurement area by the irradiation unit; and the second measurement area based on an imaging result by the imaging unit based on the first irradiation process. A determination process is performed to determine whether or not the difference between the average brightness and the target brightness is equal to or greater than a predetermined threshold value ,
Wherein when the difference of the second average luminance measuring area and the target brightness at decision processing is determined to or greater than the predetermined threshold value, the light irradiation intensity corresponding to the first measurement area Based on the imaging result by the imaging means based on irradiation, a setting process for correcting the first irradiation intensity and setting a second irradiation intensity corresponding to the second measurement area, and the irradiation means Performing a second irradiation process for irradiating the light with the second irradiation intensity set in the setting process ;
A controller that does not execute the setting process and the second irradiation process when the difference between the average luminance of the second measurement area and the target luminance is less than a predetermined threshold value in the determination process ; A three-dimensional measuring apparatus characterized by comprising. The three-dimensional measuring apparatus according to claim 1 or 2,
The three-dimensional measuring apparatus, wherein the second measurement area is black or gray that is relatively close to black. The three-dimensional measuring apparatus according to claim 1 or 2,
The three-dimensional measuring apparatus, wherein the second measurement area is white or gray that is relatively close to white. Comprising the three-dimensional measuring device according to any one of claims 1 to 4, further comprising an inspection means for inspecting the measurement object based on a result of three-dimensional measurement of the measurement object;
The measurement object is a printed circuit board on which an electrode pattern is formed with respect to a base substrate, the first measurement area is a solder region in which solder is printed on the electrode pattern, and the second measurement area is A substrate inspection apparatus provided in a background region other than a solder region, the electrode pattern, the base substrate, a resist film covering the electrode pattern, or a resist film region covering the base substrate .

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