JP2012154664A - Substrate inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate inspection device capable of improving measurement accuracy when performing three-dimensional measurement utilizing a phase shift method.SOLUTION: A substrate inspection device 8 includes an illumination device 10 for irradiating a printed circuit board with light, a CCD camera 11 for imaging the printed circuit board, and a controller 12. The controller 12 includes: source image data storage means 24 for storing source image data captured by the CCD camera 11; extraction image data preparation means 25 for extracting respective RGB color components from the source image data; complementary image data preparation means 26 for complementing a data omission part of extraction image data; color image preparation means 27 for preparing a color luminance image on the basis of the complementary image data; two-dimensional measurement means 28 for extracting a measurement object area on the basis of the color luminance image; three-dimensional measurement means 29 for three-dimensionally measuring the measurement object; and determination means 30 for inspecting a print state of solder on the basis of the measurement result.

Description

  The present invention relates to a substrate inspection apparatus for inspecting the printing state of cream solder printed on a printed circuit board.

  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 the cream solder in a stage before being led to the reflow furnace, and a substrate inspection apparatus including a three-dimensional measurement apparatus is sometimes used for such inspection.

  For example, in a three-dimensional measurement apparatus using a phase shift method, a pattern light having a striped light intensity distribution using visible light as a light source is irradiated onto a printed circuit board by an irradiation unit. Then, the three-dimensional shape, particularly the height of the cream solder is measured by imaging the printed circuit board by the imaging means and analyzing the phase difference of the pattern light stripes from the obtained image.

  In recent years, in order to improve inspection accuracy and the like, various techniques have been proposed for acquiring a color luminance image (texture data) related to this together with an image for three-dimensional measurement by using a color camera as an imaging means. (For example, see Patent Documents 1 and 2)

JP 2006-284215 A JP 2004-53532 A

  However, when performing a three-dimensional measurement using the phase shift method, when a three-plate color camera is used as an imaging means, the structure is greatly affected by chromatic aberration, and an image is formed on the image sensor by each RGB color component. The coordinates to do are different. As a result, there is a concern that the measurement accuracy may be lowered, for example, the height measurement results obtained for the RGB color components are different.

  On the other hand, when a single-plate color camera is used, after the captured image data is decomposed for each RGB color component, the missing portion of the data is complemented. Since height measurement is performed based on the complemented image data, there is a possibility that the true height cannot be measured for the complemented pixels. As a result, there is a possibility that measurement accuracy may be reduced.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a substrate inspection apparatus capable of improving measurement accuracy in performing three-dimensional measurement using a phase shift method. .

  Hereinafter, each means suitable for solving the above-described problem will be described separately. In addition, the effect specific to the means to respond | corresponds as needed is added.

Means 1. A substrate inspection device for inspecting the printing state of cream solder printed on a printed circuit board,
Irradiation means capable of irradiating the printed circuit board with white pattern light having a striped light intensity distribution and having a plurality of phases changed;
Imaging means comprising a single plate color camera capable of imaging the surface portion of the printed circuit board irradiated with the white pattern light;
Original image data storage means for storing a plurality of kinds of original image data for three-dimensional measurement imaged by the imaging means by irradiating the plurality of white pattern lights;
Color image acquisition means for acquiring a color luminance image of the surface portion of the printed circuit board according to a predetermined procedure;
Based on the color components of the color luminance image, a solder printing area extracting means for extracting a solder printing area on which the cream solder is printed from the color luminance image;
A board inspection apparatus comprising: a solder area measuring unit that performs three-dimensional measurement by a phase shift method based on the plurality of original image data with respect to the solder printing area.

  According to the means 1, the white pattern light is irradiated to the printed circuit board, and the surface portion of the printed circuit board irradiated with the white pattern light is imaged by the imaging unit. Various image processing is performed based on this, and three-dimensional measurement such as cream solder is performed. And quality determination etc. are performed based on the said measurement result.

  In particular, this means obtains a color luminance image of the surface portion of the printed circuit board, extracts a solder print area from the color luminance image based on the color components of the color luminance image, and provides a plurality of originals for the solder print area. It is configured to perform three-dimensional measurement by the phase shift method based on image data. Since cream solder is generally white or gray, for example, “white” is extracted as a solder print area. Thus, by extracting the solder print area from the color luminance image, it is possible to specify the area according to the actual measurement data without depending on the design data or the like.

  In addition, for measurement of solder printing areas with relatively large undulations, data for all the pixels in that area is required, so this means especially with respect to solder printing areas that require measurement accuracy, data missing parts and interpolation By using original image data that does not include a value or the like, measurement data closer to a true value can be obtained even when a single-plate color camera is employed.

  Furthermore, in obtaining a color luminance image, the influence of chromatic aberration can be reduced by adopting a single-plate color camera.

  As a result, it is possible to improve measurement accuracy when performing three-dimensional measurement using the phase shift method. Furthermore, the cost can be reduced and the apparatus can be downsized as compared with the case where a three-plate color camera is employed.

  Note that “white” light includes light that is close to white by combining light of a plurality of colors such as RGB.

Mean 2. Extracted image data creating means for extracting each RGB color component from the original image data stored in the original image data storage means and creating extracted image data for each RGB color component;
A reference area extracting means for extracting a reference area serving as a reference for height measurement of the solder print area from the color luminance image based on the color component of the color luminance image;
With respect to the reference area, three-dimensional measurement is performed by a phase shift method based on the plurality of extracted image data corresponding to the color components of the reference area, or complementary image data that complements the missing data portion of the extracted image data. The substrate inspection apparatus according to the means 1, further comprising a reference area measuring means.

  According to the means 2, the reference area is extracted from the color luminance image based on the color component of the color luminance image of the surface portion of the printed circuit board, and the extracted image data suitable for the color component of the reference area with respect to the reference area. The three-dimensional measurement is performed by the phase shift method based on the above. For example, “red” is extracted as an electrode region, and “green” is extracted as a substrate region. Therefore, if the reference area is “electrode”, three-dimensional measurement is performed using the extracted image data of the red component, and if the reference area is “substrate”, the extracted image data of the green component is used. .

  As described above, regarding the measurement of the solder printing area having a relatively large undulation, data of all pixels in the area is required, but the electrode and the substrate serving as the reference area are relatively flat with a small undulation, Even if measurement is performed using extracted image data or complementary image data including a missing portion of data or a complementary value, there is no particular problem.

  In addition, when the measurement target is white cream solder, the light and darkness of the pattern light to be irradiated appears clearly, so even if a single-plate color camera is used, the resolution of any RGB color component is reduced. Although it is small, with respect to a colored measurement target (for example, “electrode”), the measurement target appears dark in pixels of a color component (for example, “blue”) different from the color component (for example, “red”) of the measurement target, The resolution may be reduced. In this respect, in this means, when performing the three-dimensional measurement of the reference region, the occurrence of such a problem is suppressed by using extracted image data or the like suitable for the color component of the reference region.

  In this way, the phase shift method can be achieved by using different types of image data and different types of image data used for the three-dimensional measurement of the area depending on the color components of the predetermined area on the color luminance image. The measurement accuracy can be remarkably improved when performing three-dimensional measurement using.

Means 3. The color image acquisition means includes
Complementary image data creation means for creating complementary image data by complementing a missing portion of data in the extracted image data created by the extracted image data creation means;
3. The substrate inspection apparatus according to claim 2, further comprising color image creation means for creating the color luminance image by combining a plurality of complementary image data created by the complementary image data creation means.

  According to the means 3, a color luminance image is created by synthesizing image data created for three-dimensional measurement. Thereby, it is possible to save the trouble of irradiating the printed circuit board with white light and capturing a color luminance image. As a result, it is possible to suppress an increase in the number of times of imaging and thus the overall measurement time, and to improve measurement efficiency.

  Further, since it can be realized by software processing such as image processing, there is no need to change the hardware surface such as providing a dedicated irradiation means for irradiating white light, and the increase in manufacturing cost can be suppressed.

  Means 4. 4. The substrate inspection apparatus according to any one of means 1 to 3, further comprising mapping means for mapping the color luminance image to the three-dimensional data obtained by the three-dimensional measurement.

  According to the means 4, by mapping the color luminance image (texture data) to the three-dimensional data, the density of the measurement object can be expressed, and the texture of the three-dimensional image can be enhanced. As a result, it is easy to instantly grasp the shape of the measurement object, and the time required for the confirmation work can be significantly reduced.

It is a schematic perspective view which shows typically the board | substrate inspection apparatus in one Embodiment. It is sectional drawing of a printed circuit board. It is a block diagram which shows the outline of a board | substrate inspection apparatus. It is a schematic diagram which shows the solder printing area | region etc. in an inspection area. It is a schematic diagram which shows the aspect in the test | inspection area of the state irradiated with pattern light. It is a flowchart which shows a test | inspection routine. It is the figure which represented the data change of image data typically. It is the figure which represented the procedure of the image processing typically.

  Hereinafter, an embodiment will be described with reference to the drawings.

  As shown in FIG. 2, the printed circuit board 1 has a flat plate shape, 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 called “solder printing area”. Portions other than the solder printing area are collectively referred to as a “reference area”. The reference area includes an area where the electrode pattern 3 is exposed (symbol A), an area where the base substrate 2 is exposed (symbol B), and the base substrate 2. 2 includes 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). 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. In this embodiment, the cream solder 4 is “white”, the electrode pattern 3 is “red”, and the base substrate 2 and the resist film 5 are “green”.

  FIG. 1 is a schematic configuration diagram schematically showing a substrate inspection apparatus 8 in the present embodiment. As shown in the figure, the board inspection apparatus 8 is provided with a mounting table 9 for mounting the printed circuit board 1 as an inspection object and a predetermined light from the obliquely upper side to the surface of the printed circuit board 1. An illuminating device 10 as an irradiating means, a CCD camera 11 as an imaging means for imaging the irradiated portion on the printed circuit board 1, and various controls, image processing, and arithmetic processing in the substrate inspection apparatus 8 are performed. And a control device 12 for this purpose.

  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). With this configuration, the inspection area 60 (see FIG. 4) can be moved. The inspection area 60 is one area in which the surface of the printed circuit board 1 is divided in advance with the size of the imaging field of view of the CCD camera 11 as one unit.

  The illumination device 10 includes a white light source and a known liquid crystal optical shutter, and is configured to be able to irradiate white pattern light having a sinusoidal (stripe) light intensity distribution that changes in phase by a quarter pitch. . In the present embodiment, it is set to irradiate each side (X-axis direction and Y-axis direction) of the rectangular inspection area 60 so that the direction of the stripes of the white pattern light obliquely intersects (FIG. 5). reference).

  In the illumination device 10, light from the light source is guided to a pair of condensing lenses by an optical fiber, and is converted into parallel light there. The parallel light is guided to a projection lens disposed in the constant temperature control device via a liquid crystal element. Then, four phase-changing pattern lights are emitted from the projection lens. As described above, when the liquid crystal optical shutter is used in the illumination device 10, when the striped pattern light is created, the illumination intensity is close to an ideal sine wave. The measurement resolution of the measurement is improved. Further, the phase shift of the pattern light can be controlled electrically, and the control system can be made compact.

  As the CCD camera 11, a single-plate color CCD camera is employed. Image data (color image data) captured by the CCD camera 11 is converted into digital signals (RGB signals) inside the CCD camera 11 and then input to the control device 12 in the form of digital signals. Then, the control device 12 performs image processing, inspection processing, and the like as described later based on the image data. In this sense, the control device 12 constitutes image processing means.

  Next, the electrical configuration of the control device 12 will be described. As shown in FIG. 3, the control device 12 includes a camera control unit 21 that controls the imaging timing of the CCD camera 11, an illumination control unit 22 that controls the illumination device 10, and a motor control unit 23 that controls the motors 15 and 16. An original image data storage unit 24 that stores image data picked up by the CCD camera 11, an extracted image data creation unit 25 that extracts RGB color components from the image data stored in the original image data storage unit 24, and an extracted image Complement image data creation means 26 for complementing missing data in extracted image data created by the data creation means 25, and a color luminance image based on the complement image data created by the complement image data creation means 26. Color image creating means (color image obtaining means) 27 and the color components of the color luminance image 2D measurement means (solder print area extraction means and reference area extraction means) 28 for extracting various measurement target areas from the color luminance image, and 3D measurement means (solder area measurement means) for performing three-dimensional measurement on various measurement objects. And reference area measuring means) 29, and determination means 30 for inspecting the printing state of the cream solder 4 based on the measurement result of the three-dimensional measuring means 29.

  Although not shown, the substrate inspection apparatus 8 includes an input unit composed of a keyboard and a touch panel, a display unit having a display screen such as a CRT or a liquid crystal, a storage unit for storing inspection results, and a solder printing machine. Output means for outputting inspection results and the like.

  Next, the inspection routine performed for each inspection area 60 will be described in detail with reference to the flowchart of FIG. This inspection routine is executed by the control device 12.

  First, in step S1, original image data storage processing is executed. More specifically, when the printed circuit board 1 is placed on the mounting table 9, the control device 12 drives and controls the motors 15 and 16, and a predetermined inspection area 60 on the printed circuit board 1 is imaged in the imaging field of view of the CCD camera 11 ( White pattern light irradiation area). Subsequently, the control device 12 drives and controls the illumination device 10 to start irradiating the white pattern light, and shifts the phase of the white pattern light by a quarter (“π / 2”) pitch by four ways. Irradiate. At the same time, the control device 12 drives and controls the CCD camera 11 to image the inspection area 60 irradiated with the white pattern light of each phase, and acquire four kinds of original image data.

  The original image data storage unit 24 sequentially stores the image data picked up by the CCD camera 11 in a predetermined memory. In the present embodiment, four types of image data having different phases are stored for each inspection area 60. For example, image data captured when phase 1 (phase is “θ + 0”) is stored as original image data S1, and image data captured when phase 2 (phase is “θ + π / 2”) is the original image. Image data stored as data S2 and imaged when phase 3 (phase is “θ + π”) is stored as original image data S3, and imaged when phase 4 (phase is “θ + 3π / 2”) The data is stored as original image data S4 (see FIGS. 7 and 8). FIG. 7 is a diagram schematically showing changes in the data arrangement when the resolution of the CCD camera 11 is 5 × 5 pixels per imaging field of view, for example. In FIG. 7, for the sake of convenience, a dotted pattern is added to the original data portion. FIG. 8 is a diagram schematically showing a procedure of image processing.

  In the subsequent step S2, extracted image data creation processing is performed. More specifically, the extracted image data creating unit 25 creates extracted image data obtained by extracting each RGB color component from the four types of original image data S1 to S4 stored in the original image data storage unit 24, and stores the extracted image data in a predetermined memory. Remember. That is, four types of image data with different phases are stored for each RGB color component. Specifically, image data obtained by extracting red (R) components from the original image data S1 to S4, respectively, is stored as extracted image data SR1 to SR4, and green (G) components are extracted from the original image data S1 to S4, respectively. Image data is extracted and stored as image data SG1 to SG4, and image data obtained by extracting the blue (R) component from the original image data S1 to S4 is extracted and stored as extracted image data SB1 to SB4 (see FIGS. 7 and 8).

  In step S3, a complementary image data creation process is performed. More specifically, the supplemental image data creating unit 26 performs a complementing process for complementing the missing data portion in the extracted image data SR1 to SR4 created by the extracted image data creating unit 25, and the supplemented image data is predetermined. Store in the memory.

  The CCD camera 11 (single-plate color CCD camera) has a different wavelength range that can be imaged for each pixel. Therefore, in the extracted image data SR1 to SR4 extracted from the original image data S1 to S4 (see the upper part of FIG. 7) captured by the CCD camera 11, there is a missing part of data (see the blank part in the middle part of FIG. 7). Exists. Here, a process of filling a data missing portion existing in the extracted image data SR1 to SR4 and the like is executed.

  For example, in the extracted image data SR1 to SR4 of the red (R) component, the average value or the like of the original data “R” of adjacent pixels around the predetermined data missing portion is written as the complementary data “r”. Thus, the complementary image data HR1 to HR4. Similarly, in the extracted image data SG1 to SG4 of the green (G) component, the average value or the like of the original data “G” of adjacent pixels around the predetermined data missing portion is written as the complementary data “g”. Thus, it is set as complementary image data HG1 to HG4. In the extracted image data SB1 to SB4 of the blue (R) component, by writing the average value or the like of the original data “B” of neighboring pixels around the predetermined data missing portion as the complementary data “b”, It is set as complementary image data HB1 to HB4.

  In step S4, color image data creation processing is performed. More specifically, the color image creating means 27 first synthesizes four types of complementary image data HR1 to HR4, HG1 to HG4, and HB1 to HB4 for each RGB color component, whereby an image without stripes for each RGB color component. Data is created and stored in a predetermined memory. Specifically, four types of complementary image data HR1 to HR4 of the red (R) component are combined to create red stripe-free image data RT. Similarly, four types of complementary image data HG1 to HG4 of the green (G) component are combined to create green component non-striped image data GT. Four types of complementary image data HB1 to HB4 of the blue (B) component are synthesized to create blue component non-striped image data BT.

  Subsequently, the color image creation means 27 synthesizes the stripe-free image data RT, GT, BT of the RGB color components to create a color luminance image KT without stripes and stores it in a predetermined memory. The color luminance image KT is an image similar to the color luminance image obtained by irradiating white light (white uniform light) having a constant light intensity and phase.

  In step S5, an area extraction process is executed. More specifically, the two-dimensional measurement unit 28 determines color information of each pixel of the color luminance image KT and extracts various measurement target areas. Specifically, a range of “white” pixels is extracted as the solder print area 61, a range of “red” pixels is extracted as the exposed electrode area 62 of the electrode pattern 3, and a range of “green” pixels is extracted. It is extracted as a substrate region 63 where the base substrate 2 or the resist film 5 is exposed (see FIG. 4).

  In step S6, a three-dimensional measurement process is executed. More specifically, the three-dimensional measuring unit 29 performs three-dimensional measurement on various measurement objects based on the color luminance image KT, such as the original image data S1 to S4, the extracted image data SR1 to SR4, and the complementary image data HR1 to HR4. (Mainly height measurement or volume measurement). Specifically, for the solder printing area 61, three-dimensional measurement is performed by a known phase shift method based on the four original image data S1 to S4 having different phases. On the other hand, with respect to a reference region serving as a height measurement reference (height reference plane), a plurality of extracted image data SR1 to SR4 or the like suitable for the color components of the reference region, or complementary image data HR1 to HR4 are used. Based on the known phase shift method, three-dimensional measurement is performed. For example, when the electrode region 62 is used as a reference surface, red component extracted image data SR1 to SR4 are used, and when the substrate region 63 is used as a reference surface, green component extracted image data SG1 to SG4 are used. Is used.

  In the known phase shift method, the light intensities I1, I2, I3, and I4 of the measurement target points on the image data are given by the following formulas (1) to (4).

I1 = αsinθ + β (1)
I2 = αsin (θ + π / 2) + β (2)
I3 = αsin (θ + π) + β (3)
I4 = αsin (θ + 3π / 2) + β (4)
However, α: reflectance, β: offset component, θ: position information for deriving height.

  Then, the following formula (5) is derived from these formulas (1) to (4).

θ = arctan {(I1-I3) / (I2-I4)} (5)
Then, using this position information θ, the three-dimensional coordinates (X, Y, Z) of the measurement target point such as cream solder 4 on the printed circuit board 1 are obtained, and the three-dimensional shape, in particular, the height is measured. .

  In this way, the printing range of the cream solder 4 that is higher than the reference surface is detected here, and the amount of the printed cream solder 4 is calculated by integrating the height of each part within this range. The

  In step S <b> 7, the determination unit 30 determines the quality of the printed state of the cream solder 4 based on the measurement result obtained as described above. More specifically, the data such as the position, area, height or amount of the cream solder 4 obtained as described above is compared with the reference data set in advance, and whether or not this comparison result is within an allowable range. The quality of the printed state of the cream solder 4 in the predetermined inspection area 60 is determined. Thus, the inspection routine related to one inspection area 60 is completed.

  While the inspection routine is being performed, the control device 12 drives and controls the motors 15 and 16 to move the printed circuit board 1 to the next inspection area 60. Thereafter, the series of processes described above is performed for all inspections. Repeated in area 60.

  As described above in detail, in the present embodiment, the printed circuit board 1 is irradiated with white pattern light, and the surface portion of the printed circuit board 1 irradiated with the white pattern light is imaged by the CCD camera 11. Various image processing is performed based on this, and three-dimensional measurement of the cream solder 4 or the like is performed. And quality determination etc. are performed based on the said measurement result.

  In particular, in the present embodiment, when performing three-dimensional measurement by the phase shift method, a color luminance image KT of the surface portion of the printed circuit board 1 is acquired, and solder is obtained from the color luminance image KT based on the color components of the color luminance image KT. The print area 61, the electrode area 62, and the like are extracted. By extracting the solder print area 61 and the like from the color luminance image KT in this way, it is possible to specify the area in accordance with the actual measurement data without depending on the design data or the like.

  In addition, regarding the measurement of the solder printing area 61 having a relatively large undulation, the data of all the pixels in the area is required. Therefore, in the present embodiment, the lack of data regarding the solder printing area 61 that particularly requires the measurement accuracy. By using the original image data S1 to S4 that do not include a portion, a complementary value, or the like, measurement data closer to a true value can be obtained even when a single-panel color camera is employed.

  On the other hand, the electrode pattern 3 or the like serving as the reference region has a relatively flat surface with a small undulation, and measurement is performed using extracted image data SR1 to SR4 including missing data portions and complementary values, and complementary image data HR1 to HR4. Even if it is performed, since there is no particular trouble, in the present embodiment, the extracted image data SR1 to SR4 and the like suitable for the color components of the electrode region 62 and the like are used for the electrode region 62 and the like.

  Further, when the measurement target is white cream solder 4, the light and darkness of the stripes of the pattern light to be irradiated appears clearly. Therefore, even when a single-plate color camera is used, the resolution is reduced in any color component of RGB. Although the fear is small, with respect to a colored measurement target (for example, “electrode pattern 3”), the measurement target is different in a pixel having a color component (for example, “blue”) different from the color component (for example, “red”) of the measurement target. It may appear dark and the resolution may be reduced. In this respect, in the present embodiment, when performing three-dimensional measurement of the electrode region 62 and the like, the occurrence of such a problem is caused by using the extracted image data SR1 to SR4 and the like suitable for the color components of the electrode region 62 and the like. Suppressed.

  Furthermore, when acquiring the color luminance image KT, the influence of chromatic aberration can be suppressed by adopting a single-plate color camera.

  In this way, the phase shift is achieved by using different types of image data and using different types of image data depending on the color components of the predetermined area on the color luminance image KT, depending on the type of image data used for the three-dimensional measurement of the area. In performing three-dimensional measurement using the method, the measurement accuracy can be remarkably improved. Furthermore, the cost can be reduced and the apparatus can be downsized as compared with the case where a three-plate color camera is employed.

  In addition, in this embodiment, the color luminance image KT is created by synthesizing the complementary image data HR1 to HR4 for three-dimensional measurement. Thereby, it is possible to omit the trouble of separately irradiating the printed circuit board 1 with white light and capturing the color luminance image KT. As a result, it is possible to suppress an increase in the number of times of imaging and thus the overall measurement time, and to improve measurement efficiency.

  In addition, since it can be realized by software processing such as image processing, it is not necessary to change the hardware surface, such as providing a dedicated irradiation means for irradiating white light, and the increase in manufacturing cost can be suppressed.

  In addition, it is not limited to the description content of the said embodiment, For example, you may implement as follows. Of course, other application examples and modification examples not illustrated below are also possible.

  (A) In the above embodiment, the embodiment is implemented when measuring the printed circuit board 1 in which the cream solder 4 is “white”, the electrode pattern 3 is “red”, and the base substrate 2 and the resist film 5 are “green”. However, the present invention is not limited to this, and may be embodied when measuring a printed circuit board having a different configuration, such as a printed circuit board in which the base substrate 2 is white or gray that is relatively close to white.

  (B) In the above-described embodiment, the color luminance image KT is obtained by synthesizing the complementary image data HR1 to HR4 for three-dimensional measurement. Alternatively, the color luminance image KT may be obtained by irradiating white light (white uniform light) having a constant light intensity (luminance) and phase by the illumination device 10. Or it is good also as a structure which provides the other illuminating device which irradiates white light (white uniform light) separately from the illuminating device 10 which irradiates white pattern light, and switches both.

  (C) The light source of the illuminating device 10 is not limited to the white light source of the said embodiment, For example, it is good also as a structure which can irradiate light near white combining light sources of multiple colors, such as RGB.

  (D) In the phase shift method of the above embodiment, the phase of the white pattern light is changed by a quarter pitch. However, the present invention is not limited to this, and the phase of the white pattern light is changed by a third pitch. It is good also as composition changed.

  (E) In the above-described embodiment, the acquired color luminance image KT is used only for performing extraction processing of various measurement target regions. However, the present invention is not limited to this, and may be used for other purposes. For example, it is good also as a structure provided with the mapping means which maps the color luminance image KT with respect to the three-dimensional data obtained by three-dimensional measurement. With such a configuration, it is possible to express the density of the measurement object and to enhance the texture of the three-dimensional image. As a result, it is easy to instantly grasp the shape of the measurement object, and the time required for the confirmation work can be significantly reduced.

  (F) In the above embodiment, the CCD sensor (CCD camera 11) is employed as the image sensor (imaging means), but the image sensor is not limited to this. For example, a CMOS or the like may be employed.

  (G) In the above embodiment, both the solder print area 61 and the electrode area 62 (reference area) are extracted from the color luminance image KT. However, the present invention is not limited to this, and at least the solder is extracted from the color luminance image KT. Only the print area 61 may be extracted. In such a case, the reference area may be specified based on design data or the like, and three-dimensional measurement may be performed based on extracted image data or the like set in advance as image data corresponding to the color component of the reference area. Good.

  DESCRIPTION OF SYMBOLS 1 ... Print board, 2 ... Base board, 3 ... Electrode pattern, 4 ... Cream solder, 5 ... Resist film, 8 ... Board inspection apparatus, 9 ... Mounting stand, 10 ... Illumination device, 11 ... CCD camera, 12 ... Control apparatus 24 ... Original image data storage means, 25 ... Extracted image data creation means, 26 ... Complementary image data creation means, 27 ... Color image creation means, 28 ... Two-dimensional measurement means, 29 ... Three-dimensional measurement means, 30 ... Determination means , 60 ... Inspection area, 61 ... Solder print area, 62 ... Electrode area, 63 ... Substrate area, S1 to S4 ... Original image data, SR1 to SR4, SG1 to SG4, SB1 to SB4 ... Extracted image data, HR1 to HR4 HG1 to HG4, HB1 to HB4 ... complementary image data, RT, GT, BT ... image data without stripes, KT ... color luminance image.

Claims (4)

A substrate inspection device for inspecting the printing state of cream solder printed on a printed circuit board,
Irradiation means capable of irradiating the printed circuit board with white pattern light having a striped light intensity distribution and having a plurality of phases changed;
Imaging means comprising a single plate color camera capable of imaging the surface portion of the printed circuit board irradiated with the white pattern light;
Original image data storage means for storing a plurality of kinds of original image data for three-dimensional measurement imaged by the imaging means by irradiating the plurality of white pattern lights;
Color image acquisition means for acquiring a color luminance image of the surface portion of the printed circuit board according to a predetermined procedure;
Based on the color components of the color luminance image, a solder printing area extracting means for extracting a solder printing area on which the cream solder is printed from the color luminance image;
A board inspection apparatus comprising: a solder area measuring unit that performs three-dimensional measurement by a phase shift method based on the plurality of original image data with respect to the solder printing area. Extracted image data creating means for extracting each RGB color component from the original image data stored in the original image data storage means and creating extracted image data for each RGB color component;
A reference area extracting means for extracting a reference area serving as a reference for height measurement of the solder print area from the color luminance image based on the color component of the color luminance image;
With respect to the reference area, three-dimensional measurement is performed by a phase shift method based on the plurality of extracted image data corresponding to the color components of the reference area, or complementary image data that complements the missing data portion of the extracted image data. The substrate inspection apparatus according to claim 1, further comprising a reference area measuring unit. The color image acquisition means includes
Complementary image data creation means for creating complementary image data by complementing a missing portion of data in the extracted image data created by the extracted image data creation means;
The substrate inspection apparatus according to claim 2, further comprising a color image creation unit that creates the color luminance image by combining a plurality of complementary image data created by the complementary image data creation unit. .   4. The substrate inspection apparatus according to claim 1, further comprising mapping means for mapping the color luminance image to the three-dimensional data obtained by the three-dimensional measurement.

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