JP5759271B2 - Electronic component mounting equipment - Google Patents

Description

  The present invention relates to an electronic component mounting apparatus that generates height data from two-dimensional image data obtained by an imaging means and enables three-dimensional component recognition.

  Conventionally, as a method of detecting a three-dimensional shape using a camera as an imaging means, a plurality of image data is acquired by changing the relative distance between the camera and the three-dimensional shape as a subject, and each image data is There is one that obtains a focused pixel from the contrast, obtains the focal length of all the pixels by interpolation, and obtains the three-dimensional shape of the subject as three-dimensional data (see, for example, Patent Document 1).

Japanese Patent No. 2960684

  However, the above-described prior art is a technique for obtaining three-dimensional three-dimensional data, that is, a height at each pixel position in the imaging area. The image data obtained by imaging is subjected to image processing to determine the shape of the electronic component to be mounted. It could not be applied to an electronic component mounting apparatus that calculates features (for example, outer shape, center position, etc.).

  An object of the present invention is to obtain external information of an electronic component to be mounted with higher accuracy using image data obtained by imaging.

  According to the first aspect of the present invention, the component placement unit on which the electronic component is placed, the image pickup unit that takes an image of the electronic component placed on the component placement unit, and the distance between the component placement unit and the image pickup unit are movably adjusted. An imaging control unit that controls the movable unit, the movable unit, and the imaging unit to obtain a plurality of image data with different distances between the component placement unit and the imaging unit for the electronic component, and the plurality of image data A distance measurement processing unit that obtains a focal point position of the component placement unit from the imaging unit in each pixel based on contrast of contrast in the same pixel of the plurality of image data for each of the plurality of pixels in the imaging range; The image within a partial range of the imaging area from the in-focus position of each pixel in the imaging area by the imaging means and the luminance value of each pixel in the plurality of image data. Obtains the luminance values at the focused position of, characterized in that it comprises a local omnifocal image generating unit that generates a local omnifocal image made up of the brightness value at the focus position.

  The invention described in claim 2 has the same configuration as that of the invention described in claim 1, and generates the local omnifocal image by limiting the range of the contrast or the in-focus position. Features.

The invention described in claim 3 has a configuration similar to that of the invention described in claim 1 or 2, and stores a template image for storing a local omnifocal template image that is a template image of the local omnifocal image of an electronic component. A storage unit; and a defect inspection unit that determines whether the component is defective based on a determination as to whether the local omnifocal image generated by the local omnifocal image generation unit matches a local omnifocal template image. It is characterized by.
A local omnifocal template image may be created from 3D CAD data of a part, or may be created from imaging data of a non-defective sample part.

According to the first aspect of the present invention, the in-focus position is acquired from the contrast at each pixel within the imaging range of the plurality of image data. That is, a plurality of images with different distances between the component placement unit and the imaging means (hereinafter referred to as “imaging distance”) are obtained, and in the image data based on each imaging, the contrast with the surroundings is obtained for each pixel. Contrast is compared for the same pixel of data. As a result, the pixel is in focus at the imaging distance of the image data having the maximum contrast value.
Note that the image data having the maximum contrast for one pixel is in the state closest to the in-focus position, and does not necessarily coincide completely with the in-focus position. Therefore, when image data having the maximum contrast is captured. The image pickup distance at may be approximately regarded as the in-focus position, and the in-focus position may be obtained more accurately from the image pickup distances of the two image data having the first and second contrast magnitudes. .
Then, the height at each pixel on the electronic component can be calculated from the focal position of the component placement unit and the imaging means.
By calculating the height of each pixel within a part of the imaging area up to a plurality of points on the electronic component by the above method, the heights at various points on the surface of the electronic component can be obtained.
Then, when the height is obtained at each point on the surface of the electronic component, for each point on the surface of the electronic component, the luminance at the corresponding pixel position is obtained from the image data of the imaging distance that matches the in-focus position at each point. Get the value (luminance value). When there is no image data that matches the in-focus position, the brightness value of the image data that approximates the in-focus position may be adopted, or from the brightness values of a plurality of image data that approximate the in-focus position. The luminance value at the in-focus position may be calculated approximately.
Then, a local omnifocal image (data) can be generated by acquiring a luminance value in a focused state for pixels within a partial range of the imaging area.
Since this local omnifocal image is in focus at all pixels, the entire image can be made clearer.
For this reason, by obtaining such a local omnifocal image, it is possible to obtain high accuracy in image processing and image analysis in the case of extracting or specifying a characteristic part or center position of an electronic component based on a captured image.
In addition, since an omnifocal image is generated by limiting to a part of the imaging area, image processing such as extracting or specifying a characteristic part or center position of an electronic component based on the captured image is performed more quickly and processed. It is possible to reduce the burden.

According to the second aspect of the present invention, since a local all-in-focus image is generated by limiting the range with respect to the contrast or in-focus position, an unnecessary portion in the image, for example, the background of an electronic component, etc. can be easily excluded. It becomes possible.
For example, when a certain level of contrast cannot be obtained with any image data, the in-focus position is not included in the range of the imaging distance at which each image data was captured. In other words, the arrangement surface (background portion) of the component arrangement portion that will be the farthest from the imaging means can be easily eliminated by limiting the contrast.
Even if the in-focus position is obtained, by limiting the in-focus position itself, only the parts that should be detected according to the necessity of mounting work, such as protruding parts and recessed parts, can be obtained. An omnifocal image can be obtained by extraction, and the amount of processing data can be reduced, thereby enabling efficient processing.

According to the third aspect of the present invention, the matching with the local omnifocal template image is determined based on the generated local omnifocal image by, for example, matching processing, and thereby the quality of the component is determined. It is possible to prevent the mounting of certain electronic components.
For example, when the electronic component to be mounted is a normal component, the degree of correlation between the local omnifocal image and the local omnifocal template image is high, and the electronic component is determined as a normal electronic component. On the other hand, when the electronic component is warped or the like, only a part of the local omnifocal image is obtained, so that the degree of correlation becomes low and it can be determined that the electronic component is defective. At the time of determining the defect, for example, it is desirable to issue an error notification to the control for executing the operation control of component mounting.

It is a perspective view of the electronic component mounting apparatus which is this embodiment. It is a perspective view which shows the structure of the periphery of an imaging device. It is a block diagram which shows the control system of an electronic component mounting apparatus. It is explanatory drawing which showed the method of calculating | requiring contrast in a primary filter calculating part. It is explanatory drawing which showed the method of smoothing in a secondary filter calculating part. It is a diagram which shows the smoothed contrast value in the image data from which imaging height differs about one focus pixel. FIG. 5 is a diagram showing a smoothed contrast value in image data having different imaging heights for one target pixel, and shows a case where a peak cannot be obtained. It is an example of a display of the height image data in a display apparatus. It is an example of a display of the local omnifocal image data in a display apparatus. It is a side view of a good electronic component. It is an example of the local omnifocal image of the electronic component which is a good product shown in FIG. It is a side view of a defective electronic component. It is an example of the local omnifocal image of the electronic component which is a defect shown in FIG. It is a flowchart shown about the process from the imaging of the electronic component attracted | sucked by the suction nozzle to the calculation of the attitude | position of an electronic component, a position, etc. in multiple times. It is a flowchart shown about the example which added the process which performs a defect test | inspection to the process of FIG. It is a perspective view which shows the example which used the component arrangement | positioning part as the stage which mounts an electronic component.

(Embodiment of the Invention)
An embodiment of the invention will be described with reference to FIGS. FIG. 1 is a perspective view of an electronic component mounting apparatus 100 according to the present embodiment. Hereinafter, as shown in the drawing, two directions orthogonal to each other on the horizontal plane are respectively referred to as an X-axis direction and a Y-axis direction, and a vertical direction orthogonal to these directions is referred to as a Z-axis direction.
The electronic component mounting apparatus 100 mounts various electronic components C on the substrate S, and as shown in FIG. 1, an electronic component feeder as a plurality of component supply devices that supply the electronic components C to be mounted. A component supply unit composed of a feeder bank 102 as an installation unit that holds a plurality of 108 (only one is shown in FIG. 1) side by side, a substrate transfer unit 103 that transfers a substrate in the X-axis direction, and a substrate by the substrate transfer unit 103 An electronic component C is provided by holding a substrate clamping mechanism 104 as a substrate holding unit for performing an electronic component mounting operation on the substrate S provided in the middle of the transport path and a plurality of suction nozzles 105 as component placement units so as to be movable up and down. A head 106 for holding the image and an imaging means for imaging the electronic component C sucked by the suction nozzle 105 in order to obtain various information required for the mounting operation. The apparatus 1 (see FIG. 3), the XY gantry 107 as a moving mechanism that drives and conveys the head 106 to an arbitrary position in a work area including the component supply unit and the substrate clamping mechanism 104, and the above-described configurations. A base frame 114 to be mounted and supported, a host controller 120 as operation control means for performing operation control of each of the above components, and an image processing apparatus 10 for processing image data obtained by imaging by the imaging apparatus 1 are provided.

  In the electronic component mounting apparatus 100, the host controller 120 has mounting data in which various setting contents related to mounting of the electronic component C are recorded, and the electronic component C to be mounted from the mounting data and the electronic component C of the electronic component C The component receiving position 108a based on the installation position of the feeder 108 and the like and the data indicating the mounting position on the board are read out, and the XY gantry 107 is controlled to allow the head 106 to receive the electronic component C at the receiving position 108a and the mounting position. Then, the head 106 is controlled at each position to perform the lifting and lowering operation and the suction or release operation of the suction nozzle 105, and the operation control of mounting the electronic component C is executed.

(Substrate transport means and substrate holder)
The substrate transport unit 103 includes a transport belt (not shown), and transports the substrate along the X-axis direction by the transport belt.
Further, as described above, the substrate clamp mechanism 104 for fixing and holding the substrate S at the work position when the electronic component C is mounted on the substrate is provided in the middle of the substrate transfer path by the substrate transfer means 103. . The substrate clamping mechanism 104 is provided, and the substrate S is clamped at both ends in a direction orthogonal to the substrate transport direction. Below the substrate clamping mechanism 104, there are provided a plurality of support rods that abut against the lower surface side of the substrate S during clamping and support the substrate S so that it does not bend downward when electronic components are mounted. A stable mounting operation of the electronic component C is performed while the substrate S is held by these.

(XY gantry)
The XY gantry 107 includes an X-axis guide rail 107a that guides the movement of the head 106 in the X-axis direction, and two Y-axis guide rails 107b that guide the head 106 in the Y-axis direction together with the X-axis guide rail 107a. , An X-axis motor 109 that is a drive source that moves the head 106 along the X-axis direction, and a Y-axis motor 110 that is a drive source that moves the head 106 in the Y-axis direction via the X-axis guide rail 107a. ing. By driving the motors 109 and 110, the head 106 can be transported to almost the entire region between the two Y-axis guide rails 107b.
Each of the motors 109 and 110 positions the suction nozzle 105 via the head 106 by being recognized by the host controller 120 and controlled so as to have a desired rotation amount.
Further, the two feeder banks 102 and the substrate clamping mechanism 104 are both disposed within the transportable area of the head 106 by the XY gantry 107 due to the necessity of the electronic component mounting work.

(head)
The head 106 includes a suction nozzle 105 (see FIG. 1) that holds the electronic component C by air suction at the tip, a Z-axis motor 111 as a lifting mechanism that lifts and lowers the suction nozzle 105 along the Z-axis direction, A θ-axis motor 112 for adjusting the angle of the electronic component C held by rotating the nozzle 105 around the Z-axis direction is provided.
The suction nozzle 105 is supported by the head 106 so that it can be moved up and down and rotated in the state along the Z-axis direction. The electronic component C can be received or mounted by raising and lowering and the angle of the electronic component C can be adjusted by rotating. It has become.

(Feeder bank and electronic component feeder)
The feeder bank 102 is provided at one end of the base frame 114 in the Y-axis direction (front side in FIG. 1) along the X-axis direction. The feeder bank 102 includes a long flat portion along the XY plane, and a plurality of electronic component feeders 108 and the like are arranged and mounted on the upper surface of the flat portion along the X-axis direction (see FIG. In FIG. 1, only one electronic component feeder 108 is shown, but actually, a plurality of electronic component feeders 108 and the like are mounted side by side).
Further, the feeder bank 102 includes a latch mechanism (not shown) for holding each electronic component feeder 108 and the like, and each electronic component feeder 108 and the like is attached to or separated from the feeder bank 102 as necessary. Is possible.

  The above-described electronic component feeder 108 holds a tape reel on which a tape with electronic components C arranged and arranged at a uniform interval is wound at the rear end, and the supply position of the electronic component C to the head 106 at the upper end. It has the delivery part which is. The X and Y coordinate values indicating the position of the transfer part of the electronic component C in a state where the electronic component feeder 108 is attached to the feeder bank 102 are recorded in the mounting data described above.

(Imaging device)
FIG. 2 is a perspective view showing a configuration around the imaging device 1.
The imaging device 1 is a camera provided on the base frame 114 on the opposite side of the feeder bank 102 with the substrate transport means 103 interposed therebetween, and is arranged with its line of sight facing vertically upward. That is, the electronic component C sucked by the suction nozzle 105 is imaged from below.
The camera of the image pickup means 1 is provided with an optical system including a CCD or CMOS image pickup device for picking up a subject image and a fixed focus lens provided in front of the image pickup device. That is, the imaging means 1 is a fixed focus camera. Note that an image signal obtained at the time of imaging by the imaging apparatus 1 is output to the image processing apparatus 10.

An illumination device 2 is provided immediately above the imaging means 1. The illumination device 2 has a square shape in a plan view, a rectangular parallelepiped case 2a, a plurality of light emitting elements 2b that irradiate light from the four sides of the bottom of the case, and a plurality of light emitting elements that irradiate light from four sides of the upper part of the case. It is comprised from the element 2c.
The case 2a of the illuminating device 2 is open at the top and bottom. The electronic component C sucked by the suction nozzle 105 from the upper opening is lowered by driving the Z-axis motor 111 and enters the case 2a, and the lower opening is irradiated with light from all sides. The electronic device C is imaged by the imaging device 1 through the above.

(Control system for electronic component mounting equipment)
FIG. 3 is a block diagram showing a control system of the electronic component mounting apparatus 100. As shown, the X-axis motor 109, the Y-axis motor 110 of the XY gantry 107, the Z-axis motor 111 that moves the suction nozzle 105 up and down in the head 106, and the θ-axis motor 112 that rotates the suction nozzle 105, respectively. It is connected to the host controller 120 via a drive circuit (not shown).
The host controller 120 controls the execution of imaging by the imaging device 1 and the execution of light irradiation by the illumination device 2. And the image signal by the imaging of the imaging device 1 is input to the image processing device 10 as described above.

The host controller 120 has a list of electronic components C to be mounted and their mounting order, a mounting position of each electronic component C on the substrate S, and a receiving position indicating which electronic component feeder 108 each electronic component C receives from. Are mainly provided with a memory (not shown) for storing mounting schedule data, and the like, and a CPU 121 for executing a mounting operation control program.
When mounting electronic components, the mounting schedule data is read, the X-axis and Y-axis motors 109 and 110 are controlled, the head 106 is transported to a predetermined receiving position of the electronic component feeder 108, and the Z-axis motor 111 is controlled. Then, the electronic component C is picked up by the suction nozzle 105, moved to the image pickup apparatus 1 to pick up the electronic component C from below, and then transported to the board mounting position determined in the mounting schedule data. Implement the implementation.
And it mounts about all the electronic components C defined by the mounting schedule data, and operation | movement control is complete | finished.

  The host controller 120 is communicably connected to the image processing apparatus 10. Then, the information on the center position of the electronic component C and the angle around the Z axis obtained based on the result of the analysis of the omnifocal image generated by imaging the electronic component C is received from the image processing apparatus 10, and The mounting position of the electronic component C and the angle deviation around the Z-axis are corrected by controlling the X-axis and Y-axis motors 109 and 110 and the θ-axis motor 112, and then the mounting operation on the substrate S is controlled. .

In addition, the host controller 120 controls the Z-axis motor 111 so that the height of the suction nozzle 105 is changed at regular intervals in the Z-axis direction when the electronic component C is mounted. The imaging apparatus 1 is controlled so that the picked-up electronic component C is imaged from vertically below. That is, the host controller 120 functions as an imaging control unit.
For example, the imaging device 1 is configured to raise the suction nozzle 105 to a predetermined height starting from a position where the lower end portion of the suction nozzle 105 is in focus, and to capture the electronic component C at uniform intervals. Control.
The upward movement amount of the suction nozzle 105 at the time of imaging and the number of times of imaging are stored in a memory (not shown) and can be arbitrarily set from the outside.
Note that imaging may be performed while lowering the suction nozzle 105 in the same range.

(Image processing device)
Then, the image processing apparatus 10 acquires a plurality of image data by performing the imaging a plurality of times, and the focal position at the position of each pixel constituting the image (with the imaging apparatus 1 in the case where one pixel is in focus) (Relative position or distance with respect to the suction nozzle 105), and an all-focus image consisting of an image focused on all pixels, or an image focused on a portion of pixels within a certain height range in the electronic component C The process which produces | generates the local omnifocal image which consists of is performed.

  For this reason, as shown in FIG. 3, the image processing apparatus 10 includes an A / D converter 11 that performs A / D conversion on an image signal obtained by a plurality of times of imaging by the imaging apparatus 1 and generates image data for each imaging. The image storage unit 12 that stores these image data, the processing unit 20 that generates the height data, the height image data, and the omnifocal image data of the electronic component C from each image data, and the height that stores the height data. A processing result storage unit 30 comprising a height data storage unit 31, a height image storage unit 32 for storing height image data, and an omnifocal image storage unit 33 for storing omnifocal image data, omnifocal image data and height Local omnifocal image generation unit 41 that generates local omnifocal image data from the data, local omnifocal image storage unit 42 that stores the generated local omnifocal image data, and image processing on the local omnifocal image data A component position detection processing unit 13 that calculates the posture and position of the electronic component C, a template image storage unit 52 that stores image data of a local omnifocal template image that is a template image of a local omnifocal image of the electronic component, and a template A defect inspection unit 51 for performing a defect inspection from the image data of the local omnifocal template image held in the image storage unit 52 and the local omnifocal image data held in the local omnifocal image storage unit 42, and a defect inspection result A three-dimensional shape inspection unit 50 including an inspection result storage unit 53 to be held, and a CPU 14 that controls execution of processing of each unit and storage of data are provided.

In addition, the processing unit 20 includes a primary filter calculation unit 21 that calculates a contrast value in each pixel of all image data, a secondary filter calculation unit 22 that smoothes the contrast value in each pixel, and a smoothed contrast value. A height calculation unit 23 that calculates a focal position at each pixel from the height, and a height image that generates height image data indicating the height at each pixel position of the electronic component C by a luminance value corresponding to the height. A generation unit 24 and an omnifocal image generation unit 25 that generates omnifocal image data including an image in which each pixel that images each part of the electronic component C is in focus are provided.
Hereinafter, each part of the image processing apparatus 10 will be described in order.

The A / D converter 11 converts the image signal output from the imaging device 1 during each imaging in the movement of the suction nozzle 105 for one stroke to generate image data for each imaging. One image data is a record of brightness values individually detected for all pixels constituting one frame.
All the image data are stored in the image storage unit 12.

The primary filter calculation unit 21 of the processing unit 20 calculates the contrast for all the pixels in the image data of each captured image.
FIG. 4 is an explanatory diagram showing a method for obtaining the contrast by the primary filter calculation unit 21. When the pixel for which the contrast is to be calculated is the pixel of interest (i, j) (i, j is an XY coordinate value indicating the pixel position) and the luminance value is I (i, j), the expression (1 As shown in (4), with respect to the four directions consisting of the 45 ° oblique direction and the vertical direction and the horizontal direction around the pixel of interest, ± dx for the X-axis direction, ± dy for the Y-axis direction, The sum of the differences between the luminance values of a total of eight pixels and the target pixel that are separated by ± dx and ± dy is obtained as the contrast Lm (i, j) in the target pixel.
The contrast Lm (i, j) may be obtained more simply by omitting the comparison with each pixel in the oblique direction, as shown in the equation (2).

Dx and dy are predetermined integers. As an example, dx and dy are about 1 to 10 pixels, but may be increased or decreased.
In addition, when the contrast is obtained by the above method, strictly speaking, it is not possible to obtain the contrast for the pixels corresponding to the dx column or the dy column from the outer edge of all the pixels arranged in a plane, and the pixels are excluded from the processing target. However, since it is a very small range from the whole, “contrast of all pixels” is described for convenience.

The secondary filter calculation unit 22 performs smoothing according to the following equation (3) based on the contrast Lm (i, j) calculated by the primary filter calculation unit 21 for all pixels in the image data of each captured image.

That is, when the contrast smoothing is performed on the target pixel (i, j), the contrast of all the pixels in the addition region shown in FIG. Calculated by averaging the values.
Note that N is a predetermined integer. For example, the value is appropriately selected according to the resolution.
In addition, since smoothing is performed by the above-described method, it is not possible to perform smoothing on pixels for N columns from the outer edge of all pixels for which contrast is calculated. In this case as well, since this is also a very small range from the whole, “smoothing for all pixels” is described for convenience.

The height calculation unit 23 compares the smoothed contrast value at the same pixel position of each image data based on the smoothed contrast value (secondary filter result) of all the pixels of all the image data, The in-focus position at each pixel is acquired. That is, the height calculation unit 23 functions as a distance measurement processing unit.
FIG. 6 is a diagram illustrating smoothed contrast values in image data having different imaging heights (distance from the tip of the suction nozzle 105 to the imaging device 1) for the pixel of interest.
The contrast value (same when smoothed) is higher as the imaging means is closer to the focused state.
Therefore, by determining the height at which the smoothed contrast value becomes the maximum value for the target pixel, it is possible to determine the in-focus position at the target pixel.
Note that the imaging height at which the image was actually captured does not necessarily exactly match the in-focus position, but in that case, the imaging height that maximizes the smoothed contrast value is approximately set as the in-focus position. The smoothed contrast value may be determined from two imaging heights exceeding a predetermined threshold value (for example, 80% of the maximum value of the obtained smoothed contrast value is set as a threshold value). An average may be taken as the in-focus position.
Also, for the pixel of interest, the smoothed contrast value at the imaging height of each image data (distance from the tip of the suction nozzle 105 to the imaging device 1) approximates a normal distribution curve, so the normal distribution formula N ( μ, σ ² ) may be generated and the average value μ may be calculated as the in-focus position.
The height calculation unit 23 calculates a focal point position in all pixels and stores this in the height data storage unit 31 as height data.

When the electronic component C sucked by the suction nozzle 105 is imaged from below, the background around the electronic component C is far from the electronic component C with respect to the imaging device 1, and the suction nozzle 105 is moved up and down. Since the image is not focused even if it is performed, as shown in FIG. 7, with respect to the pixel that has imaged such a background, a peak does not appear in the smoothed contrast value, and the in-focus position cannot be obtained. Alternatively, there is a possibility that an incorrect imaging height is recognized as the in-focus position.
Therefore, in the height calculation unit 23, as shown in FIG. 7, a predetermined threshold value K is set in advance for the smoothed contrast value, and when the imaging height does not exceed any imaging height, The pixel is excluded from the processing target. Thereby, an unnecessary background area | region can be excluded and only the pixel which imaged the electronic component C can be made into a process target.
Note that the threshold value K can be easily obtained by a technique such as taking a trial image of the electronic component and the background and obtaining a contrast value that cannot be obtained from the background image.

The height image generation unit 24 normalizes the height data stored in the height data storage unit 31 to luminance values, generates a height image, and stores the height image in the height image storage unit 32.
As a normalization method, the luminance of the pixel for each in-focus position within the range from the minimum value to the maximum value of the in-focus position of all pixels (excluding excluded background pixels) included in the height data. Allocate the full range of value tones. For example, in the case of 256 gradations, the luminance value 255 is assigned to the minimum value, and the luminance value 0 is assigned to the maximum value. As a result, height image data in which the in-focus positions of all the pixels (excluding excluded background pixels) included in the height data are replaced with luminance values corresponding to the height is generated, and the height image is stored. Stored in the unit 32. In this height image data, an image with higher brightness is generated at a point closer to the imaging device 1 of the electronic component C.
Further, the brightness value 0 is stored for the pixels excluded by the height calculation unit 23.

  Further, as a normalization method, for example, the range of the in-focus position is determined in advance and the in-focus position within the range is determined in advance without normalizing in the range of the minimum value to the maximum value of the in-focus position actually obtained. Normalization is performed by allocating luminance values of all gradations to positions and replacing each focused position data in the height data stored in the height data storage unit 31 with corresponding luminance values. You can go.

Note that a display control unit that connects the display device to the image processing apparatus 10 and controls to display the generated height image data may be provided.
FIG. 8 shows a display example of height image data on the display device. As described above, the part close to the imaging device 1 side on the lower surface of the electronic component C can be displayed with high brightness, and the part farther away on the imaging device 1 can be displayed darker, and the three-dimensional shape can be easily visually determined by the two-dimensional image. Can be recognized. Note that the relationship between the perspective portion of the electronic component and the brightness of the display image may be reversed. Further, the display may be performed so as to be color-coded according to the height of each part of the electronic component C.

The omnifocal image generation unit 25 performs processing for generating omnifocal image data from the height data stored in the height data storage unit 31.
That is, for each pixel, the luminance value at the same pixel of the image data that matches or most closely approximates the focal position of each pixel included in the height image data is read from the image storage unit 12 and is used as the luminance value at each pixel. All pixels are individually focused images, and all-focus image data is generated.
In addition, when there is no image data in which the in-focus position in the pixel and the imaging height completely match, weighting is performed by the distance ratio between the imaging height and the in-focus position in the two image data with the closest imaging height. Then, the luminance value of each image data may be averaged, and the luminance value at the in-focus position may be calculated approximately.

Then, the omnifocal image generation unit 25 stores the generated omnifocal image data in the omnifocal image storage unit 33.
The omnifocal image data may be displayed on a display device connected to the image processing apparatus 10.

The local omnifocal image generation unit 41 refers to the height data storage unit 31 and acquires the coordinate information of the pixels whose in-focus position is a height within a preset range. Then, the luminance value in the omnifocal image storage unit 33 is extracted according to the coordinate information of each pixel within the predetermined height range, and the local omnifocal of only the portion of the electronic component C within the predetermined height range is extracted. Generate image data.
The local omnifocal image generation unit 41 stores the local omnifocal image data in the local omnifocal image storage unit 42.
Note that the luminance value 0 is stored for pixels whose in-focus position is outside the preset range and pixels that have already been excluded from the processing target.

In addition, the setting value is memorize | stored by the memory which is not shown about the height range which determines the range which extracts the local omnifocal image data in the local omnifocal image generation part 41. FIG. Further, the setting values in the memory may be arbitrarily set by providing input means.
The local omnifocal image data may also be displayed using the display device described above.
FIG. 9 shows a display example of local omnifocal image data on the display device. As described above, on the lower surface of the electronic component C, it is possible to display an image in which all the points are in focus while the height is different only for the portion within the predetermined height range.

The defect inspection unit 51 of the three-dimensional shape inspection unit 50 refers to the local omnifocal image storage unit 42 and inspects the degree of correlation with an image stored in the template image storage unit 52 in advance. Then, if the correlation degree is within a preset range, it is determined to be a non-defective product and the non-defective product is stored in the inspection result storage unit 53. If it is outside the preset range, it is determined as defective, and the fact that it is defective is stored in the inspection result storage unit 53.
This defect inspection result may also be displayed using the display device described above.
FIG. 10 is a side view of a non-defective product of the electronic component C, and FIG. 11 is a local omnifocal image in a predetermined height range H defined by the local omnifocal image generation unit 41 shown in FIG. It is an example of a local omnifocal image. This FIG. 11 may be a template image.
12 is a side view of a defective part in which the electronic part C is warped, and FIG. 13 is a local omnifocal image in a predetermined height range H shown in FIG. Since the electronic component C is warped, when a local omnifocal image is generated, only a part of the omnifocal image can be obtained, and in an extreme case, it may not be obtained at all. Therefore, the correlation value with the template image becomes low, and FIG. 13 is determined to be defective.

Based on the result of the inspection result storage unit 53, the component position detection processing unit 13 performs predetermined image processing based on the local omnifocal image data in the local omnifocal image storage unit 42, for example, predetermined electronic components by matching or the like. The direction of the shape portion is obtained, or the center position of the electronic component C is obtained by calculating the position of the center of gravity.
Thus, the positional deviation amount of the electronic component C with respect to the center of the suction nozzle 105, the angle of the electronic component C with respect to the center of the suction nozzle 105, the attitude of the electronic component C, and the like are obtained, and the component position detection processing unit 13 Information is transmitted to the host controller 120 side.
As a result, the CPU 121 of the host controller 120 corrects the orientation of the electronic component C sucked by the rotation control of the θ-axis motor 112 for the suction nozzle 105 and corrects the positional deviation amount with respect to the suction nozzle 105 to thereby correct the substrate of the electronic component C. Positioning with respect to S can be performed.

FIG. 14 is a flowchart illustrating processing from a plurality of times of imaging of the electronic component C sucked by the suction nozzle 105 to calculation of the posture, position, and the like of the electronic component C.
The processing contents will be described in order according to FIG.
First, the host controller 120 reads the upward movement amount of the suction nozzle 105 and the number of imaging operations set in the memory (step S1).
Then, the imaging apparatus 1 is controlled to image the electronic component C in a state where the suction nozzle 105 is at the imaging start position (step S3), and the Z-axis motor 111 is controlled to raise the suction nozzle 105 to the next imaging height. (Step S5). An image signal obtained by imaging by the imaging device 1 is transmitted to the image processing device 10, A / D converted, and stored in the image storage unit 12 as image data.
Then, the host controller 120 determines whether imaging for the set number of imaging has been completed. If the imaging has not yet been completed, the process returns to step S3 to perform imaging at the next position.
Further, when imaging for the set number of imaging is completed, the process proceeds to processing on the image processing apparatus 10 side. Furthermore, in order to improve the processing tact, the host controller 120 and the image processing apparatus 10 may cooperate to efficiently perform imaging, Z-axis movement, and image processing.

The primary filter calculation unit 21 of the image processing apparatus 10 calculates the contrast for each pixel of each image data (step S9). Then, the secondary filter calculation unit 22 smoothes the contrast in each pixel (step S11).
The height calculation unit 23 obtains a peak position, that is, a focal position at each pixel position from the smoothed contrast value of each pixel in all image data, and stores the peak position in the height data storage unit 31 as height data. (Step S13).

Next, the height image generation unit 24 normalizes the height data to luminance values and generates a height image (step S15).
Further, the omnifocal image generation unit 25 generates omnifocal image data from the height (focus position) at each pixel position indicated by the height data and each image data (step S17).

Next, the local omnifocal image generation unit 41 reads the set value of the height range for performing local extraction from the omnifocal image data (step S19), and all of the electronic components C within the set height range are read out. Local omnifocal image data obtained by extracting only the focal image data is generated (step S21) and output to the component position detection processing unit 13 (step S23).
The component position detection processing unit 13 calculates the posture, orientation, and position of the electronic component C from the local omnifocal image data, and transmits it to the host controller 120 (step S25).
Thereby, the host controller 120 corrects the orientation and position of the electronic component C, performs the mounting operation on the substrate S, and ends the control.

FIG. 15 is a flowchart showing processing for performing a defect inspection in addition to the processing shown in FIG.
The inspection contents will be described in order according to FIG. First, a local omnifocal template image used for matching processing performed later is created and stored in the template image storage unit 52 (step S31).
The local omnifocal template image may be created from the 3D CAD data of the part, or a good sample product may be imaged to generate a local omnifocal image from the image data, thereby forming a local omnifocal template image.
And the process similar to the process to FIG.14 S1-step S23 is performed, and a local omnifocal image is acquired (step S33).
Next, a matching process is performed using the local omnifocal template images stored in the local omnifocal image storage unit 42 and the template image storage unit 52 (step S35).
Further, a defect judgment criterion (for example, a preset correlation degree threshold value) for the matching result is acquired (step S37), defect determination is performed from the matching result and the defect determination criterion (step S39), and the determination result is used as the inspection result. Store in the storage unit 53.
If the stored inspection result satisfies the criteria, a component recognition process that is the same process as step S25 described above is performed (step S41). If the inspection result does not satisfy the standard, the host controller 120 is notified of the failure and the electronic component C is not mounted.

(Technical effects of electronic component mounting equipment)
The electronic component mounting apparatus 100 can obtain local omnifocal image data within a certain height range in a state where the image processing apparatus 10 is in focus for all pixels. When the position, orientation, feature shape, and the like are obtained by image processing, the processing accuracy can be improved. In addition, since local omnifocal image data that falls within a part of the imaging area is generated, it is possible to reduce the processing load and increase the processing speed in the subsequent image processing.

  Further, since the height calculation unit 23 of the image processing apparatus 10 sets a threshold value for the smoothed contrast and generates height data in a range exceeding the threshold value, an unnecessary background image or the like is processed from the processing target. As a result, it is possible to reduce the processing load for the processing after the height calculation unit 23 and to shorten the processing time.

  Furthermore, local omnifocal image data is generated from an image taken by the image processing apparatus 10, and a three-dimensional shape inspection is relatively easy and with a light processing burden only by matching processing with a local omnifocal template image. It becomes possible to do.

(Other)
The local omnifocal image generation unit 41 of the image processing apparatus 10 generates local omnifocal image data based on the omnifocal image data generated by the omnifocal image generation unit 25, but is not limited thereto.
That is, the local omnifocal image generation unit 41 refers to the height data storage unit 31 and acquires the coordinate information of the pixels whose in-focus position is within a preset range, and the heights of these pixels are the height. Local omnifocal image data is generated by reading out from the image storage unit 12 the luminance value at the same pixel of the image data that matches or most closely approximates the focal point position of each pixel included in the image data, and uses it as the luminance value at each pixel. You may do it.
Accordingly, local omnifocal image data can be generated without going through the omnifocal image generation unit 25, and the omnifocal image generation unit 25 can be omitted to simplify the configuration.

Further, in the electronic component mounting apparatus 100, the electronic component C picked up by the suction nozzle 105 is picked up using the suction nozzle 105 as a component placement unit, and omnifocal image data and local omnifocal image data are based on the image data. The electronic component C is acquired and various types of information are acquired. However, the electronic component C may be imaged in other states, and omnifocal image data and local omnifocal image data may be generated from the captured image. Is possible.
For example, as shown in FIG. 16, a stage 201 as a component placement unit, an imaging device 202 that can image an electronic component C on the stage 201 from above, and a lifting device that can move the stage 201 or the imaging device 202 up and down ( (Not shown in the figure), and taking an image with the imaging device 202 from above while changing the distance between the electronic components C on the stage 201 to obtain a plurality of image data having different heights. You may produce | generate omnifocal image data and local omnifocal image data from each image data.
For example, by providing such a configuration in the electronic component mounting apparatus 100, it is possible to obtain information such as the outer shape and orientation of the electronic component C before being sucked by the suction nozzle 105.

  In addition, the stage 201 shown in FIG. 16 can be fixed without moving up and down, and the imaging apparatus 202 can be moved up and down, and the stage 201 can be imaged from above.

1 Imaging device (imaging means)
10 Image processing device 23 Height calculation unit (ranging processing unit)
25 omnifocal image generation unit 41 local omnifocal image generation unit 51 defect inspection unit 52 template image storage unit 100 electronic component mounting apparatus 105 suction nozzle (component arrangement unit)
106 Head 111 Z-axis motor (movable part)
120 Host controller (imaging controller)
201 stage (part placement section)
202 Imaging device (imaging means)
C Electronic component S Substrate H Local omnifocal image generation range

Claims (3)

A component placement section where electronic components are placed;
Imaging means for imaging the electronic component arranged in the component arrangement unit;
A movable part that movably adjusts the distance between the component placement part and the imaging means;
An imaging control unit that controls the movable unit and the imaging unit to obtain a plurality of image data with different distances between the component placement unit and the imaging unit for the electronic component;
For each of the plurality of pixels within the imaging range of the plurality of image data, based on the contrast of the contrast of the plurality of image data in the same pixel, the in-focus position of the component placement unit is determined from the imaging unit in each pixel. A ranging processing unit to be obtained;
The brightness value at the in-focus position in the pixels within a partial range of the imaging area from the in-focus position at each pixel in the imaging area by the imaging means and the brightness value of each pixel in the plurality of image data And a local omnifocal image generation unit that generates a local omnifocal image composed of luminance values at the in-focus position.   The electronic component mounting apparatus according to claim 1, wherein the local omnifocal image is generated by limiting a range of the contrast or the in-focus position. A template image storage unit that stores image data of a local omnifocal template image that is a template image of the local omnifocal image of an electronic component;
A defect inspection unit that determines whether or not the component is defective based on a determination as to whether the local omnifocal image generated by the local omnifocal image generation unit matches the local omnifocal template image. The electronic component mounting apparatus according to claim 1 or 2.