JPWO2016166807A1 - Appearance inspection apparatus and appearance inspection method - Google Patents

Abstract

The tilt cameras 31b to 31e are disposed to be tilted with respect to the normal direction (vertical direction Z) of the surface 10a of the substrate 10 and capture the side surfaces of the solders 91 and 92 existing on the surface 10a of the substrate 10. Suitable (Figure 7). Then, based on the measurement region R (I) obtained by imaging the measurement region R (I) set for the substrate 10 with the tilt cameras 31b to 31e, the three-dimensional shape Dt (I) of the measurement region R (I) is measured. To do. Therefore, even when the measurement region R (I) is set to include the side surfaces 91a and 92a of the solders 91 and 92 existing on the substrate 10, the three-dimensional shape Dt of the side surfaces 91a and 92a of the solders 91 and 92 is provided. It is possible to accurately measure (I).

Description

  The present invention relates to an appearance inspection apparatus and an appearance inspection method for inspecting the appearance of a substrate.

  The vision inspection apparatus described in Patent Document 1 includes a first camera that directly faces an inspection object and a lattice pattern irradiation unit that irradiates the lattice pattern, and shows how the lattice pattern irradiated to the inspection object is deformed. Based on the result of imaging with one camera, the height of the inspection object is measured.

Special table 2014-510276 gazette

  Such a technique can be used, for example, to inspect the appearance of a substrate on which components are attached by solder. However, the first camera faces the inspection object. Therefore, when inspecting the substrate, there are cases where the three-dimensional shape of the side surface of an object (solder or component) existing on the substrate cannot always be accurately measured. Incidentally, in patent document 1, the 2nd camera arrange | positioned around the 1st camera is provided. However, this second camera only confirms whether the parts are lifted or not inserted, and is not sufficient to solve such a problem.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique that makes it possible to accurately measure the three-dimensional shape of the side surface of an object present on a substrate.

  In order to achieve the above object, an appearance inspection apparatus according to the present invention is held by a substrate holding unit that holds a substrate, a projector that irradiates light toward the substrate held by the substrate holding unit, and the substrate holding unit. Based on a captured image obtained by capturing the measurement area with the tilt camera while irradiating light from the projector to the measurement area set with respect to the substrate, and the tilt camera arranged with respect to the normal direction of the surface of the substrate. A control unit that measures the three-dimensional shape of the measurement region.

  In order to achieve the above object, the visual inspection method according to the present invention includes a step of setting a measurement region on the substrate, and a light is applied to the measurement region, and the surface is inclined with respect to the normal direction of the surface of the substrate. The measurement area is imaged by the tilted camera arranged to obtain a captured image, and the three-dimensional shape of the measurement area is measured based on the captured image.

  The tilt camera provided in the present invention (appearance inspection apparatus and appearance inspection method) configured as described above is arranged to be inclined with respect to the normal direction of the surface of the substrate, and compared with the above-mentioned facing camera. It is suitable for capturing the side surface of an object present on the surface of a substrate. And based on the picked-up image which imaged the measurement area | region set with respect to the board | substrate with the inclination camera, the three-dimensional shape of a measurement area | region is measured. Therefore, even when the measurement region is set so as to include the side surface of the object existing on the substrate, it is possible to accurately measure the three-dimensional shape of the side surface of the object.

  It is possible to accurately measure the three-dimensional shape of the side surface of the object present on the substrate.

The perspective view which shows typically an example of the inspection head with which the external appearance inspection apparatus concerning this invention is provided. The top view which shows typically an example of the test | inspection head of FIG. 1 is a block diagram schematically illustrating an appearance inspection apparatus according to the present invention. The flowchart which shows an example of the image pick-up performed for a board | substrate inspection. The top view which illustrates direction of a measurement area typically. The flowchart which shows an example of the image process performed for a board | substrate inspection. The figure explaining typically the advantage which a tilt camera has. The figure explaining another advantage which a tilt camera has typically. The figure which shows typically a mode that the board | substrate in which different types of components are mixed is test | inspected.

  FIG. 1 is a perspective view schematically showing an example of an inspection head provided in an appearance inspection apparatus according to the present invention. FIG. 2 is a plan view schematically showing an example of the inspection head of FIG. In both figures and the following figures, the horizontal direction X, the horizontal direction Y, and the vertical direction Z orthogonal to each other are shown as appropriate. The inspection head 3 has the surface 10a of the substrate 10 held horizontally as an inspection target, and performs imaging while irradiating (projecting) a predetermined pattern of light onto the surface 10a of the substrate 10 within the inspection range F3. .

  As shown in both figures, the inspection heads 3 are a front-facing camera 31a located in the center in plan view from the vertical direction Z, and four heads arranged concentrically at regular intervals around the optical axis Aa of the front-facing camera 31a. Tilt cameras 31b to 31e. In both figures, different symbols 31a to 31e are assigned to the five cameras. However, in the following, the common symbol 31 is used as appropriate when the individual cameras are not distinguished. As the cameras 31a to 31e, for example, CCD (Charge Coupled Device) cameras can be used. The five cameras 31a to 31e are arranged so as to oppose the inspection range F3 on the surface 10a of the substrate 10, and the inspection range F3 can be accommodated in each field of view. In other words, the visual fields of the five cameras 31 a to 31 e overlap each other in the inspection range F <b> 3 on the surface 10 a of the substrate 10.

  The directly facing camera 31a is arranged so that its optical axis Aa is parallel to the vertical direction Z, and faces the inspection range F3 from above. Therefore, the angle formed by the optical axis Aa of the directly facing camera 31a and the surface 10a of the substrate 10 is 90 degrees. The directly facing camera 31a has a telecentric lens, and images the surface 10a of the substrate 10 in the inspection range F3 through the telecentric lens.

  The tilt cameras 31b to 31e are arranged such that their optical axes Ab to Ae are tilted with respect to the vertical direction Z, and face the inspection range F3 from obliquely above. The angles (elevation angles) formed by the optical axes Ab to Ae of the tilt cameras 31b to 31e and the surface 10a of the substrate 10 are equal to each other and are acute angles of less than 90 degrees. On the other hand, in plan view from the vertical direction Z, the optical axes Ab to Ae of the four tilt cameras 31b to 31e are different by 90 degrees. That is, when the angle (azimuth angle) is defined counterclockwise starting from the coordinate axis X (horizontal direction X) in the plan view of FIG. 2, the angle of the optical axis Ab of the tilt camera 31b is 45 degrees, and the tilt camera 31c The angle of the optical axis Ac is 135 degrees, the angle of the optical axis Ad of the tilt camera 31d is 225 degrees, and the angle of the optical axis Ae of the tilt camera 31e is 315 degrees.

  Further, the inspection head 3 includes four projectors 32b to 32e (projectors) arranged concentrically at equal intervals around the optical axis Aa of the directly facing camera 31a. In both figures, different projectors 32b to 32e are assigned to the four projectors. However, in the following description, when the projectors are not distinguished from each other, the common reference 32 is appropriately used. Each of the projectors 32b to 32e irradiates the inspection range F3 with a striped pattern light (pattern light) whose light intensity distribution changes in a sine wave shape. The stripes constituting the pattern light are parallel to the direction intersecting with the optical axes Ab to Ae of the four tilt cameras 31b to 32e at 45 degrees in plan view from the vertical direction Z.

Each of the projectors 32b to 32e has an LED (Light Emitting
And a digital micromirror device that reflects the light from the light source toward the inspection range F3. Then, by adjusting the angles of the respective micromirrors of the digital micromirror device, it is possible to irradiate the inspection range F3 with four kinds of pattern lights having different phases. That is, the inspection head 3 can measure the three-dimensional shape in the inspection range F3 by the phase shift method by performing imaging with the cameras 31a to 31e while changing the phase of the pattern light irradiated from the projectors 32b to 32e. it can.

  The four projectors 32b to 32e are arranged so that their optical axes Bb to Be are inclined with respect to the vertical direction Z, and face the inspection range F3 from obliquely above, and are on the surface 10a of the substrate 10. The inspection range F3 can be accommodated in each light irradiation range. In other words, the pattern light irradiation ranges of the four projectors 32b to 32e overlap each other in the inspection range F3 on the surface 10a of the substrate 10.

The angles (elevation angles) formed by the optical axes Bb to Be of the projectors 32 b to 32 e and the surface 10 a of the substrate 10 are equal to each other and are acute angles of less than 90 degrees. On the other hand, in a plan view from the vertical direction Z, the optical axes Bb to Be of the four projectors 32b to 32e are different by 90 degrees. That is, when the angle (azimuth angle) is defined counterclockwise with the coordinate axis X (horizontal direction X) as the starting line in the plan view of FIG. 2, the angle of the optical axis Bb of the projector 32b becomes 0 degrees, and the optical axis of the projector 32c The angle of Bc is 90 degrees, the angle of the optical axis Bd of the projector 32d is 180 degrees, and the angle of the optical axis Be of the projector 32e is 270 degrees. As described above, the projectors 32b to 32e are arranged between the tilt cameras 31b to 32e adjacent in the circumferential direction.

  FIG. 3 is a block diagram schematically illustrating an appearance inspection apparatus according to the present invention. The appearance inspection apparatus 1 controls the transport conveyor 2, the inspection head 3, and the drive mechanism 4 by the control device 100, and acquires the three-dimensional shape of the measurement region set for the substrate 10 (printed substrate). The appearance of the substrate 10 is inspected.

  The transport conveyor 2 transports the substrate 10 along a predetermined transport path. Specifically, the transfer conveyor 2 carries the substrate 10 before inspection into the inspection position in the appearance inspection apparatus 1 and holds the substrate 10 horizontally at the inspection position. Thereby, the surface 10a of the flat substrate 10 is held horizontally, and the normal direction of the surface 10a of the substrate 10 coincides with the vertical direction Z. When the inspection of the substrate 10 at the inspection position is completed, the conveyor 2 carries the substrate 10 after the inspection out of the appearance inspection apparatus 1.

  The inspection head 3 faces the surface 10a of the substrate 10 held by the conveyor 2 from the upper side in the vertical direction Z. As described above, the inspection head 3 images the inspection range F3 with the cameras 31a to 31e while irradiating the inspection range F3 on the surface 10a of the substrate 10 with the pattern light from the projectors 32b to 32e. The drive mechanism 4 drives the inspection head 3 in the horizontal directions X and Y and the vertical direction Z by a motor while supporting the inspection head 3. By driving the drive mechanism 4, the inspection head 3 can fit the measurement region set on the surface 10a of the substrate 10 within the inspection range F3.

  The control device 100 has a main control unit 110 composed of a CPU (Central Processing Unit) and a memory, and the main control unit 110 controls the various parts of the device, thereby executing an inspection. Also. The control device 100 has a user interface 200 composed of input / output devices such as a display, a keyboard, and a mouse. A user inputs a command to the control device 100 via the user interface 200, and the control device 100 You can check the inspection results. Furthermore, the control device 100 includes an irradiation control unit 120 that controls the projectors 32b to 32e, an imaging control unit 130 that controls the cameras 31a to 31e, a drive control unit 140 that controls the drive mechanism 4, and a storage unit 150 that stores data and the like. And an image processing unit 160 that executes image processing.

  Then, the control device 100 inspects the substrate 10 by executing an imaging operation for imaging the measurement region using the inspection head 3 and an image process for performing arithmetic processing on the captured image acquired by the imaging operation. Next, a specific description will be given by exemplifying a case where the shape of solder for attaching an electronic component to the surface 10a of the substrate 10 is measured and the quality of the solder is inspected based on the measurement result.

  FIG. 4 is a flowchart showing an example of image capturing executed for substrate inspection. The flowchart of FIG. 4 is executed according to the control of the main control unit 110. In step S <b> 101, the main control unit 110 specifies the measurement region R (I) (FIG. 5) based on the component data De stored in the storage unit 150. That is, the component data De indicates the position and shape of the component on the surface 10 a of the substrate 10. Accordingly, the main control unit 110 obtains the position of the solder for attaching the component to the surface 10a of the substrate 10 from the component data De, and sets the measurement region so as to include the solder. A plurality of components are attached to the surface 10a of the substrate 10, and a plurality of solder attachment locations (pads) are provided. Correspondingly, a plurality of measurement regions R (I) are set.

  Subsequently, the identification number I for identifying the measurement region R (I) to be imaged is reset to zero (step S102), and the identification number I is incremented (step S103). If the identification number I is equal to or less than the maximum value Imax (“NO” in step S104), the drive control unit 140 adjusts the position of the inspection head 3 by the drive mechanism 4, thereby making the inspection head 3 the I-th measurement. It is made to oppose area | region R (I). Here, the maximum value Imax is the number of measurement regions R (I) specified in step S101. As a result, the I-th measurement region R (I) is included in the inspection range F3 of the inspection head 3. In step S106, the main control unit 110 determines the direction of the I-th measurement region R (I).

  FIG. 5 is a plan view schematically illustrating the direction of the measurement region. In the figure, a rectangular chip component 8 is taken as an example, and the arrangement direction E of the chip component 8 is parallel to the horizontal direction X, the arrangement pattern 2 orthogonal to the horizontal direction X, and the horizontal direction X. Each of the arrangement patterns 3 inclined by 45 degrees is shown. Here, the arrangement direction E of the chip component 8 is the length direction of the chip component 8 in a plan view from the vertical direction Z, and terminals 81 and 82 provided at both ends of the chip component 8 are arranged in the example of FIG. Match the direction. As shown in FIG. 5, on the first side E <b> 1 in the arrangement direction E of the chip component 8, the terminal 81 is attached to the pad 11 provided on the surface 10 a of the substrate 10 with the solder 91, and the chip component 8 is arranged in the arrangement direction E. On the second side E2 (the opposite side of the first side E1), the terminal 82 is attached to the pad 12 provided on the surface 10a of the substrate 10 by the solder 92.

  In step S106 of FIG. 4, the main control unit 110 determines the direction of the slope of the solders 91 and 92 (in other words, the direction of the normal of the slope) in which the measurement area R (I) is set as the measurement area. Judged as the direction of R (I). Specifically, on which end of the first side E1 and the second side E2 of the chip component 8 the terminals 81, 82 to which the solders 91, 92, which are the setting targets of the measurement region R (I), are attached, are located. Confirm. And if it confirms that it is located in the end of the 1st side E1, it will judge that measurement field R (I) faces the 1st side E1 of arrangement direction E, and if it confirms that it is located in the end of the 2nd side E2, Then, it is determined that the measurement region R (I) faces the second side E2 in the arrangement direction E.

  In the specific example of FIG. 5, in the example of “arrangement pattern 1”, it is determined that the measurement region R (I) faces the first side E1 in the arrangement direction E parallel to the horizontal direction X. In the example of “arrangement pattern 2”, it is determined that the measurement region R (I) faces the first side E1 in the arrangement direction E orthogonal to the horizontal direction X. Alternatively, in the example of “arrangement pattern 3”, it is determined that the measurement region R (I) faces the first side E1 in the arrangement direction E inclined by 45 degrees from the horizontal direction X.

  In step S107, the main control unit 110 selects the projector 32 to be used for imaging the measurement region R (I) from the projectors 32b to 32e based on the determination result of the direction of the measurement region R (I). Specifically, the projector 32 that satisfies the irradiation condition of irradiating the measurement region R (I) with pattern light from the side where the measurement region R (I) faces is selected.

  Therefore, when the measurement region R (I) faces the first side E1 in the arrangement direction E, the projector 32 that irradiates the pattern light from the first side E1 to the measurement region R (I) is selected. Here, the projector 32 that irradiates the pattern light from the first side E1 to the measurement region R (I) in the side view from the direction orthogonal to the arrangement direction E (in other words, in the arrangement direction E). All projectors 32 that irradiate pattern light from the first side E1 to the measurement region R (I) with respect to R (I) are applicable.

  In the specific example of FIG. 5, in the example of “arrangement pattern 1”, in the arrangement direction E parallel to the horizontal direction X, light is irradiated from the first side E1 with respect to the measurement region R (I) in the inspection range F3. One projector 32d (FIG. 2) to be selected is selected. In the example of “arrangement pattern 2”, in the arrangement direction E orthogonal to the horizontal direction X, one projector 32c that irradiates light from the first side E1 with respect to the measurement region R (I) in the inspection range F3 is selected. The Alternatively, in the example of “arrangement pattern 3”, two projectors 32c that irradiate light from the first side E1 with respect to the measurement region R (I) in the inspection range F3 in the arrangement direction E inclined 45 degrees from the horizontal direction X. , 32d are selected. Here, the case where the measurement region R (I) faces the first side E1 in the arrangement direction E has been described as an example. However, the measurement region R (I) may face the second side E2 in the arrangement direction E. It is the same.

  Subsequently, the identification number P for identifying the projector 32 selected in step S107 is reset to zero (step S108), and the identification number P is incremented (step S109). If the identification number P is equal to or smaller than the maximum value Pmax (“NO” in step S110), a captured image necessary for measuring the three-dimensional shape of the measurement region R (I) by the phase shift method is acquired in step S111. ˜S114 is executed. Here, the maximum value Pmax is the number of projectors 32 selected in step S107.

  That is, the storage unit 150 stores the pattern data Dp (S) (S = 1, 2, 3, 4) indicating the above-described four patterns of light. The irradiation control unit 120 controls the projector 32 based on the pattern data Dp (S) read from the storage unit 150, thereby measuring the pattern light indicated by the pattern data Dp (S) from the projector 32 within the inspection range F3. The region R (I) can be irradiated.

Therefore, the identification number S for identifying the pattern light is reset to zero (step S111), and the identification number S is incremented (step S112). If the identification number S is equal to or less than the maximum value Smax (= 4) (“NO” in step S113), the five cameras 31a to 31e are caused to image the measurement region R (I) in the inspection range F3, and Captured images of each of the five cameras 31a to 31e are acquired (step S114). Note that the imaging of the measurement region R (I) is performed by exposing the five cameras 31a to 31e at the same time with only the P-th one projector 32 turned on and the other projectors 32 turned off (that is, (The exposure times of the five cameras 31a to 31e are the same). Then, steps S112 to S114 are repeatedly executed until the identification number S exceeds the maximum value Smax (“YES” in step S113). As a result, the captured images of the measurement region R (I) by the five cameras 31a to 31e are acquired while incrementing the identification number S and changing the phase of the pattern light irradiated to the measurement region R (I) (step). S114).

  In this way, a set of captured images is acquired with four images obtained by imaging the measurement region R (I) with each of the cameras 31a to 31e while irradiating light from the projector 32 with the identification number P. Accordingly, the main control unit 110 associates the measurement region R (I) with the identification number P for identifying the projector 32 that has emitted light during imaging and the identification number C for identifying the cameras 31a to 31e that have performed imaging. ) Of the captured image Ds (I, P, C).

  Then, steps S109 to S114 are repeatedly executed until the identification number P exceeds the maximum value Pmax (“YES” in step S110). Accordingly, the captured image Ds (I, P, C) of the measurement region R (I) can be acquired using all the projectors 32 selected in step S107. Until the identification number I exceeds the maximum value Imax (“YES” in step S104), steps S103 to S114 are repeatedly executed. Thereby, the captured images Ds (I, P, C) can be acquired for all the measurement regions R (I) specified in step S101. In this way, when the imaging operation of FIG. 4 is finished, image processing for performing arithmetic processing on the captured image acquired by the imaging operation is executed.

  FIG. 6 is a flowchart showing an example of image processing executed for substrate inspection. The flowchart of FIG. 6 is executed according to the control of the main control unit 110. First, the identification number I for identifying the measurement region R (I) to be subjected to image processing is reset to zero (step S201), and the identification number I is incremented (step S202). If the identification number I is equal to or less than the maximum value Imax (“NO” in step S203), the main control unit 110 uses the technique in step S106 described above with reference to FIG. The direction of the region R (I) is determined (step S204).

  In step S205, the main control unit 110 determines which of the tilt cameras 31b to 31D among the captured images Ds (I, P, C) of the measurement region R (I) based on the determination result of the direction of the measurement region R (I). Whether to use the captured image Ds (I, P, C) captured at 31e is selected. Specifically, the captured image Ds (I, P, C) of the tilt camera 31 that satisfies the imaging condition of imaging the measurement region R (I) from the side where the measurement region R (I) faces is selected.

  Accordingly, when the measurement region R (I) faces the first side E1 in the arrangement direction E, the captured image Ds (I, P, C) of the tilt camera 31 that images the measurement region R (I) from the first side E1. Is selected. Here, the tilt camera 31 that images the measurement region R (I) from the first side E1 has the measurement region R (in the arrangement direction E) in a side view from the direction orthogonal to the arrangement direction E (in other words, in the arrangement direction E). All the tilt cameras 31 that image the measurement region R (I) from the first side E1 than I) are applicable.

  In the specific example of FIG. 5, in the example of “arrangement pattern 1”, in the arrangement direction E parallel to the horizontal direction X, the image is taken from the first side E <b> 1 rather than the measurement region R (I) in the inspection range F <b> 3. Captured images Ds (I, P, C) captured by each of the tilt cameras 31c, 31d are selected. In the example of “arrangement pattern 2”, in the arrangement direction E orthogonal to the horizontal direction X, each of the two tilt cameras 31b and 31c that capture images from the first side E1 with respect to the measurement region R (I) in the inspection range F3. The captured image Ds (I, P, C) captured by is selected. Alternatively, in the example of “arrangement pattern 3”, in the arrangement direction E inclined 45 degrees from the horizontal direction X, one inclined camera 31 c that captures an image from the first side E1 with respect to the measurement region R (I) in the inspection range F3 is provided. Selected. Here, the case where the measurement region R (I) faces the first side E1 in the arrangement direction E has been described as an example. However, the measurement region R (I) may face the second side E2 in the arrangement direction E. It is the same.

  In step S206, the image processing unit 160 uses the captured images Ds (I, P, C) of the tilt camera 31 and the facing camera 31 selected in step S205, and the three-dimensional shape Dt of the measurement region R (I). (I) is calculated. Specifically, for example, the three-dimensional shape Dt (I) may be obtained as follows.

  First, the captured image Ds (I, P, C) of the measurement region R (I) obtained by the selected tilt camera 31 is converted into the coordinate system of the directly facing camera 31. And the average of the pixel value of the captured image Ds (I, P, C) of the tilted camera 31 after the coordinate conversion and the pixel value of the captured image Ds (I, P, C) of the directly facing camera 31 is calculated for each pixel. calculate. The average calculation is performed for the captured images Ds (I, P, C) having the same phase of the pattern light of the projector 32 used at the time of imaging. As a result, the average captured image Ds (I, P, C) having the average pixel value can be acquired for four types of pattern light having different phases. Therefore, the image processing unit 160 calculates the three-dimensional shape Dt (I) of the measurement region R (I) from these average captured images Ds (I, P, C) using the phase shift method.

  In step S207, the image processing unit 160 determines the quality of the shapes of the solders 91 and 92 in the measurement region R (I) based on the calculated three-dimensional shape Dt (I). Then, steps S202 to S207 are repeatedly executed until the identification number I exceeds the maximum value Imax (“YES” in step S203). As a result, the three-dimensional shape Dt (I) is obtained for all the measurement regions R (I) specified in step S101, and pass / fail determination is executed.

  As described above, the tilt cameras 31b to 31e included in the present embodiment are disposed to be tilted with respect to the normal direction (vertical direction Z) of the surface 10a of the substrate 10 and are arranged on the surface 10a of the substrate 10. It is suitable for capturing the side surfaces of the existing solders 91 and 92 (FIG. 7). Here, FIG. 7 is a diagram schematically illustrating the advantages of the tilt camera. In other words, the side surface 91a of the solder 91 faces the normal direction of the surface 10a of the substrate 10 as compared to the arrow V1 that captures the side surface 91a of the solder 91 from the normal direction (vertical direction Z) of the surface 10a of the substrate 10. In other words, the arrow V2 that captures the side surface 91a from the direction inclined in the direction inclined to the normal direction of the side surface 91a can more accurately capture the side surface 91a of the solder 91 from the front. In this embodiment, the three-dimensional shape Dt of the measurement region R (I) is based on the measurement region R (I) obtained by imaging the measurement region R (I) set with respect to the substrate 10 by the tilt cameras 31b to 31e. (I) is measured. Therefore, even when the measurement region R (I) is set to include the side surfaces 91a and 92a of the solders 91 and 92 existing on the substrate 10, the three-dimensional shape Dt of the side surfaces 91a and 92a of the solders 91 and 92 is provided. It is possible to accurately measure (I).

  Such tilt cameras 31b to 31e also have another advantage that they are suitable for suppressing the reflection of the surface 10a of the substrate 10. FIG. 8 is a diagram schematically illustrating another advantage of the tilt camera. As shown in the column “with reflection” in FIG. 8, in the case of the arrow V <b> 1 that captures the side surface 91 a of the solder 91 from the normal direction (vertical direction Z) of the surface 10 a of the substrate 10, it is reflected by the surface 10 a of the substrate 10. The reflected light is re-reflected by the side surface 91 a of the solder 91 and enters the camera 31. Therefore, there is a possibility that the reflection surface 10 b of the substrate 10 is reflected in the captured image of the side surface 91 a of the solder 91. On the other hand, as shown in the column of “No reflection” in FIG. 8, the side surface 91 a is captured from the direction in which the side surface 91 a of the solder 91 faces the normal direction of the surface 10 a of the substrate 10. In the case of the arrow V2, occurrence of such reflection can be suppressed.

  Further, a plurality of tilt cameras 31b to 31e are provided. Therefore, the measurement region R (I) can be imaged by the tilt cameras 31b to 31e from a plurality of directions, and the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solder 91 and 92 existing on the surface 10a of the substrate 10. It is advantageous in accurately measuring.

  In addition, among the captured images Ds (I, P, C) of the plurality of tilt cameras 31b to 31e, the captured images Ds (I, P, C) used for measuring the three-dimensional shape Dt (I) of the measurement region R (I). ) Is selected based on the direction in which the tilt cameras 31b to 31e image the measurement region R (I) (steps S204 and S205). Accordingly, the three-dimensional shape Dt (I) of the measurement region R (I) using the captured image Ds (I, P, C) obtained by capturing the measurement region R (I) from an appropriate one of the plurality of imaging directions. Can be measured. Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  Specifically, as shown in steps S204 and S205 above, the component data De indicating the position and outer shape of the chip component 8 attached to the surface 10a of the substrate 10 by the solders 91 and 92 is acquired, and the measurement region R Imaging conditions to be determined in the imaging direction of the tilt cameras 31b to 31e that capture (I) are set according to the component data De. Then, the captured image Ds (I, P, C) of the tilt camera 31 that images the measurement region R (I) from the direction satisfying the imaging condition is used to measure the three-dimensional shape Dt (I) of the measurement region R (I). Use. In such a configuration, the three-dimensional shape Dt (I) of the measurement region R (I) using the captured image Ds (I, P, C) obtained by imaging the measurement region R (I) from the imaging direction selected based on the component data De. Can be measured. Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  In particular, in the present embodiment, the measurement region R (I) is set with respect to the side surfaces 91a and 92a of the solders 91 and 92. Then, an imaging condition is set based on the result of determining the positional relationship between the solder 91 and 92 and the chip component 8 attached to the substrate 10 by the solder 91 and 92 from the component data De. In such a configuration, the captured image Ds (I, P, C) obtained by capturing the measurement region R (I) from the imaging direction selected based on the positional relationship between the solders 91 and 92 and the chip component 8 from among the plurality of imaging directions. It is possible to measure the three-dimensional shape Dt (I) of the measurement region R (I). Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  Specifically, the terminal 81 (terminal 82) to which the solder 91 (solder 92) to be set in the measurement region R (I) is attached is any of the chip components 8 in the arrangement direction E parallel to the surface 10a of the substrate 10. Is determined based on the component data De (step S204). Then, if it is determined that the corresponding terminal 81 (terminal 82) is located at the end of the first side E1 (second side E2) of the chip component 8 in the arrangement direction E, it is more in the arrangement direction E than the measurement region R (I). An imaging condition for imaging the measurement region R (I) from the first side E1 (second side E2) is set. This makes it possible to accurately measure the three-dimensional shape Dt (I) of the side surface 91a (side surface 91b) of the solder 91 (solder 92) that attaches the terminal 81 (terminal 82) of the chip component 8 to the substrate 10.

  By the way, in the determination in step S205, there may be two tilt cameras 31 that satisfy the imaging condition when imaging the measurement region R (I) depending on the direction of the measurement region R (I). That is, when there are two tilt cameras 31 arranged so as to sandwich the measurement region R (I) in the direction V perpendicular to the placement direction E, the two tilt cameras 31 satisfy the imaging condition. . In the specific example of FIG. 5 described above, in the example of “placement pattern 1”, the two tilt cameras 31c and 31d satisfy the imaging conditions, and in the example of “placement pattern 2”, the two tilt cameras 31b and 31c Satisfy imaging conditions. In such a case, the three-dimensional shape Dt (I) of the measurement region R (I) is obtained by using the captured images Ds (I, P, C) of the two tilt cameras 31 and the three-dimensional shape of the measurement region R (I). The shape Dt (I) can be measured.

  That is, the captured images Ds (I, P, C) of the two tilt cameras 31 are converted into the coordinate system of the directly facing camera 31. Then, the captured image Ds (I, P, C) after the coordinate conversion of one tilt camera 31, the captured image Ds (I, P, C) after the coordinate conversion of the other camera 31, and the imaging of the directly facing camera 31. The average of the pixel values of the image Ds (I, P, C) is calculated for each pixel. At this time, the average calculation is performed for the captured images Ds (I, P, C) having the same phase of the pattern light of the projector 32 used for imaging. As a result, the average captured image Ds (I, P, C) having the average pixel value can be acquired for four types of pattern light having different phases. Therefore, the three-dimensional shape Dt (I) of the measurement region R (I) can be calculated from these average captured images Ds (I, P, C) using the phase shift method.

  Furthermore, imaging is executed by overlapping the exposure times of the two tilt cameras 31 with each other. As a result, the time required for imaging by the two tilt cameras 31 can be shortened, and the three-dimensional shape Dt (I) can be measured efficiently.

  Incidentally, there is a possibility that light emitted from the projector 32 and regularly reflected by the surface 10 a of the substrate 10 may enter the tilt camera 31. Such regular reflection light causes halation in the captured image Ds (I, P, C) of the tilt camera 31. Therefore, the captured images Ds (I, P, C) of the two tilt cameras 31 may be used complementarily to calculate the three-dimensional shape Dt (I) of the measurement region R (I). In other words, the pixel value of the portion causing halation in the captured image Ds (I, P, C) of one tilt camera 31 is not used for the above average calculation, for example, by treating it as null. And about the applicable part, only the pixel value of the picked-up image Ds (I, P, C) of the other inclination camera 31 is used. This is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10 while suppressing the influence of halation.

  Further, the projector 32 is disposed to be inclined with respect to the normal direction (vertical direction Z) of the surface 10 a of the substrate 10 held on the transport conveyor 2. In such a configuration, it is possible to irradiate the pattern light onto the side surfaces 91 a and 92 a of the solders 91 and 92 existing on the surface 10 a of the substrate 10 by the projector 32 inclined with respect to the normal direction of the surface 10 a of the substrate 10. . Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  Further, a plurality of projectors 32b to 32e are provided. Therefore, the pattern light from the projectors 32b to 32e arranged in an inclined manner can be irradiated to the measurement region R (I) from a plurality of directions, and the side surfaces 91a of the solders 91 and 92 existing on the surface 10a of the substrate 10; This is advantageous in accurately measuring the three-dimensional shape Dt (I) of 92a.

  Further, the projector 32 used for imaging the measurement region R (I) is selected from the plurality of projectors 32b to 32e based on the irradiation direction in which the projector 32 emits the pattern light to the measurement region R (I) (step S106, S107). Thereby, the tertiary of the measurement region R (I) using the captured image Ds (I, P, C) obtained by capturing the measurement region R (I) while irradiating the pattern light from the appropriate irradiation direction among the plurality of irradiation directions. The original shape Dt (I) can be measured. Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  Specifically, as shown in steps S106 and S107, component data De indicating the position and outer shape of the chip component 8 attached to the surface 10a of the substrate 10 by the solders 91 and 92 is acquired, and the measurement region R ( In I), the irradiation condition obtained in the pattern light irradiation direction of the projector 32 that irradiates the pattern light is set according to the component data De. Then, the measurement region R (I) is imaged while turning on the projector 32 that irradiates the measurement region R (I) with the pattern light from the direction satisfying the irradiation condition. In such a configuration, the tertiary of the measurement region R (I) using the captured image Ds (I, P, C) obtained by capturing the measurement region R (I) while irradiating the pattern light from the irradiation direction selected based on the component data De. The original shape Dt (I) can be measured. Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  In particular, in the present embodiment, the measurement region R (I) is set with respect to the side surfaces 91a and 92a of the solders 91 and 92. Then, irradiation conditions are set based on the result of determining the positional relationship between the solder 91 and 92 and the chip component 8 attached to the substrate 10 by the solder 91 and 92 from the component data De. In such a configuration, the picked-up image Ds (I, I, I) is obtained by imaging the measurement region R (I) while irradiating light from the irradiation direction selected based on the positional relationship between the solders 91 and 92 and the chip component 8 from the plurality of irradiation directions. P, C) can be used to measure the three-dimensional shape Dt (I) of the measurement region R (I). Therefore, it is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10.

  Specifically, the terminal 81 (terminal 82) to which the solder 91 (solder 92) to be set in the measurement region R (I) is attached is any of the chip components 8 in the arrangement direction E parallel to the surface 10a of the substrate 10. Is determined based on the component data De (step S106). Then, if it is determined that the corresponding terminal 81 (terminal 82) is located at the end of the first side E1 (second side E2) of the chip component 8 in the arrangement direction E, it is more in the arrangement direction E than the measurement region R (I). An irradiation condition is set such that pattern light is irradiated from the first side E1 (second side E2) to the measurement region R (I). This makes it possible to accurately measure the three-dimensional shape Dt (I) of the side surface 91a (side surface 91b) of the solder 91 (solder 92) that attaches the terminal 81 (terminal 82) of the chip component 8 to the substrate 10.

  By the way, in the determination in step S107, there can be two projectors 32 that satisfy the irradiation condition for irradiating the measurement region R (I) with the pattern light depending on the direction of the measurement region R (I). That is, when there are two projectors 32 arranged so as to sandwich the measurement region R (I) in the direction V orthogonal to the arrangement direction E, the two projectors 32 satisfy the irradiation condition. In the specific example of FIG. 5 described above, in the example of “arrangement pattern 3”, the two projectors 32c and 32d satisfy the irradiation condition. In such a case, the three-dimensional shape Dt (I) of the measurement region R (I) is measured using the captured image Ds (I, P, C) obtained by sequentially turning on the two projectors 32. The three-dimensional shape Dt (I) of I) can be measured.

  That is, the average of the pixel values of the captured image Ds (I, P, C) captured by lighting one projector 32 and the captured image Ds (I, P, C) captured by lighting the other projector 32 is calculated. Calculate for each pixel. The average calculation is performed for the captured images Ds (I, P, C) having the same phase of the pattern light of the projector 32 used at the time of imaging. In this way, the average captured image Ds (I, P, C) having the average pixel value can be acquired for four types of pattern light having different phases. Therefore, the three-dimensional shape Dt (I) of the measurement region R (I) can be calculated from these average captured images Ds (I, P, C) using the phase shift method.

  Such a configuration can also be applied to suppress the influence of the above-described halation. In other words, the pixel value of the portion causing halation in the captured image Ds (I, P, C) captured by using one projector 32 is not used for the above average calculation, for example, by treating it as null. To do. For the corresponding portion, only the pixel value of the captured image Ds (I, P, C) captured using the other projector 32 is used. This is advantageous in accurately measuring the three-dimensional shape Dt (I) of the side surfaces 91a and 92a of the solders 91 and 92 existing on the surface 10a of the substrate 10 while suppressing the influence of halation.

  Further, the four tilt cameras 31b to 31e are arranged circumferentially at a pitch of 90 degrees around the normal line of the surface 10a of the substrate 10. Further, the projector 32 is parallel to the direction intersecting with the optical axes Ab to Ae of the four tilt cameras 31b to 31e at 45 degrees in a plan view from the normal direction (vertical direction Z) of the surface 10a of the substrate 10. A pattern light composed of a stripe is irradiated onto the measurement region R (I). Then, based on the result of imaging the measurement region R (I) while irradiating the measurement region R (I) with the pattern light from the projector 32, the exposure times of the four tilt cameras 31b to 31e overlap each other. The three-dimensional shape Dt (I) of the measurement region R (I) is measured using the method. As a result, it is possible to reduce the time required to capture the captured image Ds (I, P, C) necessary for measuring the three-dimensional shape Dt (I) of the measurement region R (I), and to reduce the three-dimensional shape Dt. The measurement of (I) can be performed efficiently.

  Further, a front-facing camera 31a and tilt cameras 31b to 31e are provided, and the three-dimensional shape Dt (I) of the measurement region R (I) is measured using each captured image Ds (I, P, C). Was. As a result, more accurate measurement is possible.

  As described above, in the present embodiment, the appearance inspection apparatus 1 corresponds to an example of the “appearance inspection apparatus” of the present invention, the transport conveyor 2 corresponds to an example of the “substrate holding unit” of the present invention, and the projectors 32 b to 32 e. Each of them corresponds to an example of the “projector” of the present invention, each of the tilt cameras 31b to 31e corresponds to an example of the “tilt camera” of the present invention, and the directly facing camera 31a is an example of the “facing camera” of the present invention. The control device 100 corresponds to an example of the “control unit” of the present invention, the measurement region R (I) corresponds to an example of the “measurement region” of the present invention, and the component data De is the “component” of the present invention. The chip component 8 corresponds to an example of “data”, the chip component 8 corresponds to an example of “component” or “chip component” of the present invention, the terminals 81 and 82 correspond to an example of “terminal” of the present invention, and the solders 91 and 92. Corresponds to an example of “solder” of the present invention , Orientation E corresponds to an example of the "particular direction" of the present invention.

  The present invention is not limited to the above-described embodiment, and various modifications can be made to the above-described one without departing from the spirit of the present invention. For example, a specific method for calculating the three-dimensional shape Dt (I) of the measurement region R (I) from the captured image Ds (I, P, C) of the measurement region R (I) is not limited to the above example, and is conventionally known. The method can be used as appropriate.

  Further, when there are two tilt cameras 31 that satisfy the imaging condition in the determination in step S205, the measurement region R (I, P, C) is used by using the captured images Ds (I, P, C) of both the two tilt cameras 31. The three-dimensional shape Dt (I) of I) was calculated. However, the three-dimensional shape Dt (I) of the measurement region R (I) is calculated using the captured image Ds (I, P, C) of one tilt camera 31 selected from the two tilt cameras 31. It doesn't matter.

  If there are two projectors 32 that satisfy the irradiation condition in the determination in step S107, measurement is performed using the captured images Ds (I, P, C) obtained by lighting each of the two projectors 32. The three-dimensional shape Dt (I) of the region R (I) was calculated. However, the three-dimensional shape Dt (I) of the measurement region R (I) is obtained by using Ds (I, P, C) obtained by lighting one projector 32 selected from the two projectors 32. You may calculate.

  Moreover, the case where this invention was applied with respect to the external appearance inspection apparatus 1 provided with the facing camera 31a was demonstrated. However, the present invention can also be applied to the appearance inspection apparatus 1 that does not include the facing camera 31a.

  In the pattern imaging in step S114, all the tilt cameras 31b to 31e are turned on regardless of the direction of the measurement region R (I). However, what is used for calculating the three-dimensional shape Dt (I) of the measurement region R (I) is a predetermined positional relationship with respect to the measurement region R (I), that is, a captured image Ds ( I, P, C) only. Therefore, the tilt camera 31 that satisfies the imaging condition may be specified based on the determination result of the direction of the measurement region R (I) in step S106, and only the tilt camera 31 thus specified may be used for imaging in step S114.

  In addition, the three-dimensional shape Dt (I) of each measurement region R (I) may be measured while including a plurality of measurement regions R (I) in the inspection range F3. Even in such a configuration, the imaging condition is obtained for each measurement region R (I), and the tertiary of each measurement region R (I) is obtained using the captured image Ds (I, P, C) of the tilt camera 31 that satisfies the imaging condition. The original shape Dt (I) may be calculated.

  Further, in such a configuration, the exposure times of two or more tilt cameras 31 may overlap each other, and the two or more tilt cameras 31 may perform imaging. In this case, captured images Ds (I, P, C) used for calculation of the three-dimensional shape Dt (I) of the measurement region R (I) are captured images Ds (I, P, C) of the two or more tilt cameras 31. By selecting from among (C), the three-dimensional shape Dt (I) can be calculated from the appropriate captured image Ds (I, P, C). In addition, it is possible to shorten the time required to capture the captured image Ds (I, P, C) necessary for calculating the three-dimensional shape Dt (I) of the measurement region R (I). Measurement of I) can be performed efficiently.

  Further, the measured three-dimensional shape Dt (I) may be stored in the storage unit 150 as point cloud data. This allows the user to inspect the substrate 10 while performing human image processing such as changing the line of sight that displays the three-dimensional shape Dt (I) of the measurement region R (I) on the screen of the user interface 200. It becomes.

  Moreover, the case where this invention was applied to the test | inspection of the solders 91 and 92 which join the chip component 8 to the board | substrate 10 was illustrated. However, the present invention can also be applied to the inspection of the solders 91 and 92 that connect different types of components (for example, lead components) to the substrate 10 to the chip component 8.

  Furthermore, it is preferable to apply the present invention to the inspection of the substrate 10 in which various parts are mixed. FIG. 9 is a diagram schematically showing a state in which a board in which different types of components are mixed is inspected. In the example of FIG. 9, the part 8A is hidden behind the part 8B in a plan view from the vertical direction Z. Therefore, the mounting state of the component 8A cannot be inspected only with the facing camera 31a. On the other hand, in the configuration shown in the above embodiment, the mounting state of the component 8A can be inspected by imaging the component 8A with the tilt camera 31 that performs imaging from the direction indicated by the one-dot chain line arrow in FIG. It becomes possible.

  In the above description, the case of inspecting the shape of solder has been mainly described. However, the inspection target is not limited to solder, and various objects existing on the surface 10a of the substrate 10 can be the inspection target.

  As described above, specific embodiments have been illustrated and described. In the present invention, for example, at least two tilt cameras face different directions in plan view from the normal direction of the surface of the substrate. The visual field inspection apparatus may be configured such that the fields of view overlap each other in the inspection range of the surface of the substrate, and the control unit sets the measurement region within the inspection range where the fields of view of the plurality of tilt cameras overlap. Such a configuration is advantageous for accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate, because the measurement region can be imaged from a plurality of directions by the tilt camera.

  Further, the control unit sets the appearance inspection device so that the picked-up image used for measuring the three-dimensional shape of the measurement area is selected from the picked-up images of the plurality of tilt cameras based on the direction in which the tilt camera picks up the measurement area. It may be configured. As a result, it is possible to measure the three-dimensional shape of the measurement region using a captured image obtained by capturing the measurement region from an appropriate imaging direction among a plurality of imaging directions. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  Specifically, the control unit acquires component data indicating the position and outer shape of the component attached to the surface of the substrate by soldering, and sets the imaging condition to be calculated in the imaging direction of the tilt camera that images the measurement area in the component data. Accordingly, the appearance inspection apparatus may be configured so that a captured image of a tilt camera that captures the measurement region from a direction that satisfies the imaging condition is used for measuring the three-dimensional shape of the measurement region. With this configuration, it is possible to measure the three-dimensional shape of the measurement region using a captured image obtained by capturing the measurement region from the imaging direction selected based on the position and outline of the component from among a plurality of imaging directions. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  Further, the control unit sets a measurement region for the surface of the solder, and sets an imaging condition based on a result of judging the positional relationship between the solder and the component attached to the board from the component data. May be configured. With this configuration, it is possible to measure the three-dimensional shape of the measurement region using a captured image obtained by capturing the measurement region from the imaging direction selected based on the positional relationship between the solder and the component from among a plurality of imaging directions. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the solder existing on the surface of the substrate.

  Specifically, for example, when the component includes a chip component having a terminal, the control unit determines from the component data that the terminal to which the solder to be set in the measurement region is attached in a specific direction parallel to the surface of the substrate. If it is determined that the chip part is located at the first side end, the appearance inspection apparatus may be configured to set an imaging condition of imaging the measurement region from the first side of the measurement region. This makes it possible to accurately measure the three-dimensional shape of the side surface of the solder that attaches the terminal of the chip component to the substrate.

  Further, at least two tilt cameras are arranged so as to sandwich the measurement region in a direction parallel to the surface of the substrate and perpendicular to the specific direction, and the control unit measures the captured image that satisfies the imaging condition. The appearance inspection apparatus may be configured to be used for measuring the three-dimensional shape of the region. In such a configuration, the three-dimensional shape of the measurement region can be measured based on the captured image obtained by capturing the measurement region from two different directions. As a result, the three-dimensional shape of the measurement area can be measured by using the captured images of the two tilt cameras in a complementary manner. Specifically, for example, even if a part of the image captured by one tilt camera causes halation, the part can be supplemented by the image captured by the other tilt camera. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  In addition, the control unit causes the respective exposure times of at least two tilt cameras arranged so as to sandwich the measurement region in a direction parallel to the surface of the substrate and orthogonal to the specific direction to execute imaging. An appearance inspection apparatus may be configured. As a result, the time required for imaging by the two tilt cameras can be shortened, and the three-dimensional shape can be measured efficiently.

  Further, the control unit sets a plurality of measurement areas, causes at least two tilt cameras among the plurality of tilt cameras to perform imaging with overlapping exposure times, and sets the measurement area for each of the plurality of measurement areas. The appearance inspection apparatus may be configured to select a captured image used for measurement of a three-dimensional shape from captured images of tilt cameras with exposure times overlapping each other. As a result, it is possible to reduce the time required to capture a captured image necessary for measuring the three-dimensional shape of the measurement region, and it is possible to efficiently measure the three-dimensional shape.

  In addition, the appearance inspection apparatus may be configured such that the projector is inclined with respect to the normal direction of the surface of the substrate held by the substrate holding unit. In such a configuration, it is possible to irradiate light on the side surface of the object existing on the surface of the substrate by the projector inclined with respect to the normal direction of the surface of the substrate. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  In addition, the appearance inspection apparatus is configured to include a plurality of projectors that face different directions in a plan view from the normal direction of the surface of the substrate, and that the respective light irradiation ranges overlap each other on the surface of the substrate. Also good. In such a configuration, light from a projector disposed at an inclination can be irradiated onto the measurement region from a plurality of directions, which is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate. It is.

  In addition, the appearance inspection apparatus may be configured such that a projector used for imaging a measurement region is selected from a plurality of projectors based on an irradiation direction in which the projector irradiates light to the measurement region. Thereby, it is possible to measure the three-dimensional shape of the measurement region using a captured image obtained by imaging the measurement region while irradiating light from an appropriate irradiation direction among a plurality of irradiation directions. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  Specifically, the control unit acquires component data indicating the position and outer shape of the component attached to the surface of the substrate by soldering, and determines the irradiation condition obtained in the light irradiation direction of the projector that irradiates light to the measurement region. The appearance inspection apparatus may be configured so that the tilting camera images the measurement area while turning on a projector that is set according to the component data and illuminates the measurement area with light from the direction satisfying the irradiation condition. In such a configuration, it is possible to measure the three-dimensional shape of the measurement region using a captured image obtained by imaging the measurement region while irradiating light from the irradiation direction selected based on the position and outer shape of the component from a plurality of irradiation directions. It becomes. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  In addition, the control unit sets the measurement area on the surface of the solder, and sets the irradiation condition based on the result of judging the positional relationship between the solder and the component attached to the board from the component data. May be configured. In such a configuration, the three-dimensional shape of the measurement region is measured using a captured image obtained by capturing the measurement region while irradiating light from the irradiation direction selected based on the positional relationship between the solder and the component from a plurality of irradiation directions. Is possible. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the solder existing on the surface of the substrate.

  Specifically, for example, when the component includes a chip component having a terminal, the control unit determines from the component data that the terminal to which the solder to be set in the measurement region is attached in a specific direction parallel to the surface of the substrate. When it is determined that the chip part is located at the first side end, the appearance inspection apparatus may be configured to set an irradiation condition of irradiating the measurement region with light from the first side of the measurement region. Such a configuration is advantageous in accurately measuring the three-dimensional shape of the side surface of the solder that attaches the terminal of the chip component to the substrate.

  In addition, at least two projectors are arranged so as to sandwich the measurement region in a direction parallel to the surface of the substrate and perpendicular to the specific direction, and the control unit illuminates at least two projectors in order to capture the measurement region. As such, an appearance inspection apparatus may be configured. In such a configuration, it is possible to measure the three-dimensional shape of the measurement region based on the captured image captured while sequentially turning on two projectors that emit light from different directions. As a result, the three-dimensional shape of the measurement region can be measured by using the captured image captured by lighting one projector and the captured image captured by lighting the other projector. Specifically, even if a portion of the captured image when one of the projectors is lit up causes halation, the portion can be supplemented by the captured image when the other projector is lit. Therefore, it is advantageous in accurately measuring the three-dimensional shape of the side surface of the object existing on the surface of the substrate.

  Further, the plurality of tilt cameras include at least four tilt cameras arranged circumferentially at a pitch of 90 degrees around the normal line of the substrate surface, and the projector is provided with respect to the normal direction of the substrate surface. In plan view, the measurement area is irradiated with light having a pattern composed of stripes parallel to the optical axis of each of the four tilt cameras at 45 degrees, and the control unit irradiates the measurement area with light from the projector. The appearance inspection apparatus may be configured to measure the three-dimensional shape of the measurement area based on the result of imaging the measurement area by overlapping the exposure times of the four tilt cameras. As a result, it is possible to reduce the time required to capture a captured image necessary for measuring the three-dimensional shape of the measurement region, and it is possible to efficiently measure the three-dimensional shape.

  In addition, the camera further includes a facing camera that faces the normal direction of the surface of the substrate and has a field of view that overlaps the fields of view of the plurality of tilt cameras on the surface of the substrate, and the control unit emits light from the projector to the measurement region. The appearance inspection apparatus may be configured to measure the three-dimensional shape of the measurement region based on the captured image obtained by capturing the measurement region with the facing camera and the captured image captured by the tilt camera. As described above, by measuring the three-dimensional shape of the measurement region using the captured images of the facing camera and the tilt camera, it is possible to perform measurement with higher accuracy.

  At this time, the control unit determines the height of the measurement region in each pixel based on the image obtained by converting the captured image captured by the tilt camera into the coordinate system of the directly facing camera and the captured image captured by the directly facing camera. Thus, the appearance inspection apparatus may be configured to measure the three-dimensional shape of the measurement region.

  The control unit may configure the appearance inspection apparatus so as to hold the measured three-dimensional shape of the measurement region as point cloud data. This makes it possible to perform an inspection while performing arbitrary image processing such as changing the line of sight of the three-dimensional shape of the measurement region.

  Furthermore, the number and arrangement of each of the camera 31 and the projector 32 can be changed as appropriate.

DESCRIPTION OF SYMBOLS 1 ... Appearance inspection apparatus 10 ... Board | substrate 2 ... Conveyor (substrate holding | maintenance part)
31a ... Direct camera 31b-31e ... Tilt camera 32b-32e ... Projector 8 ... Chip parts 81, 82 ... Terminals 91, 92 ... Solder 100 ... Control device (control unit)
R (I) ... Measurement area De ... Part data E ... Arrangement direction (specific direction)
E1 ... first side E2 ... second side V ... direction orthogonal to arrangement direction F3 ... inspection range Z ... vertical direction (normal direction of substrate)
Ds (I, P, C) ... captured image

Claims (21)

A substrate holder for holding the substrate;
A projector that emits light toward the substrate held by the substrate holding unit;
An inclined camera arranged to be inclined with respect to the normal direction of the surface of the substrate held by the substrate holding unit;
Appearance provided with a control unit that measures a three-dimensional shape of the measurement region based on a captured image obtained by capturing the measurement region with the tilt camera while irradiating light from the projector to the measurement region set for the substrate Inspection device. The at least two tilt cameras are directed in different directions in a plan view from the normal direction of the surface of the substrate, and their respective fields of view overlap each other in the inspection range of the surface of the substrate,
The visual inspection apparatus according to claim 1, wherein the control unit sets the measurement region within an inspection range in which fields of view of the plurality of tilt cameras overlap.   The said control part selects the said picked-up image used for measurement of the three-dimensional shape of the said measurement area | region among the said picked-up images of each of these several inclination cameras based on the direction in which the said inclination camera images the said measurement area | region. 2. An appearance inspection apparatus according to 2.   The control unit acquires component data indicating a position and an outer shape of a component attached to the surface of the substrate with solder, and determines an imaging condition to be obtained in an imaging direction of the tilt camera that images the measurement region according to the component data. The appearance inspection apparatus according to claim 3, wherein the captured image of the tilt camera that captures the measurement area from a direction that satisfies the imaging condition is used for measurement of a three-dimensional shape of the measurement area.   The control unit sets the measurement area on the surface of the solder, and sets the imaging condition based on a result of determining a positional relationship between the solder and the component attached to the substrate from the component data. The appearance inspection apparatus according to claim 4. The component includes a chip component having a terminal,
The control unit determines from the component data that the terminal to which the solder, which is the setting target of the measurement region, is attached is located at an end on the first side of the chip component in a specific direction parallel to the surface of the substrate. Then, the appearance inspection apparatus according to claim 5, wherein the imaging condition of imaging the measurement area from the first side of the measurement area is set. At least two of the tilt cameras are arranged so as to sandwich the measurement region in a direction parallel to the surface of the substrate and perpendicular to the specific direction, and image the measurement region,
The appearance inspection apparatus according to claim 6, wherein the control unit uses the captured image satisfying the imaging condition for measurement of a three-dimensional shape of the measurement region.   The controller executes imaging by overlapping the exposure times of at least two tilt cameras arranged to sandwich the measurement region in a direction parallel to the surface of the substrate and perpendicular to the specific direction. The appearance inspection apparatus according to claim 7.   The control unit sets a plurality of measurement areas, causes at least two tilt cameras among the plurality of tilt cameras to perform imaging with overlapping exposure times, and for each of the plurality of measurement areas, The appearance inspection apparatus according to any one of claims 3 to 8, wherein the picked-up image used for measurement of a three-dimensional shape of a measurement region is selected from the picked-up images of the tilt camera with exposure times overlapping each other.   The visual inspection apparatus according to claim 1, wherein the projector is disposed to be inclined with respect to a normal direction of a surface of the substrate held by the substrate holding unit.   The visual inspection apparatus according to claim 10, further comprising: a plurality of the projectors that face different directions in a plan view from the normal direction of the surface of the substrate and whose light irradiation ranges overlap each other on the surface of the substrate. .   The visual inspection apparatus according to claim 11, wherein the projector used for imaging the measurement region is selected from the plurality of projectors based on an irradiation direction in which the projector irradiates light to the measurement region.   The control unit acquires component data indicating a position and an outer shape of a component attached to the surface of the substrate by soldering, and determines an irradiation condition to be obtained in a light irradiation direction of the projector that irradiates light to the measurement region. The appearance inspection apparatus according to claim 12, wherein the appearance inspection device is set according to data and causes the tilt camera to image the measurement area while turning on the projector that irradiates light to the measurement area from a direction satisfying the irradiation condition.   The control unit sets the measurement area on the surface of the solder, and sets the irradiation condition based on a result of determining a positional relationship between the solder and the component attached to the substrate from the component data. The appearance inspection apparatus according to claim 13. The component includes a chip component having a terminal,
The control unit determines from the component data that the terminal to which the solder, which is the setting target of the measurement region, is attached is located at an end on the first side of the chip component in a specific direction parallel to the surface of the substrate. Then, the appearance inspection apparatus according to claim 14, wherein the irradiation condition of irradiating light to the measurement region from the first side of the measurement region is set. At least two of the projectors are arranged so as to sandwich the measurement region in a direction parallel to the surface of the substrate and perpendicular to the specific direction,
The appearance inspection apparatus according to claim 15, wherein the control unit images at least two projectors in order to image the measurement region. The plurality of tilt cameras include at least four tilt cameras arranged circumferentially at a pitch of 90 degrees around a normal line of the surface of the substrate;
The projector irradiates the measurement region with light having a pattern of stripes parallel to a direction intersecting with the optical axes of the four tilt cameras at 45 degrees in a plan view from the normal direction of the surface of the substrate. And
The control unit measures a three-dimensional shape of the measurement area based on a result of imaging the measurement area while irradiating light from the projector to the measurement area and overlapping exposure times of the four tilt cameras. The visual inspection apparatus according to claim 2. The camera further comprises a facing camera that faces the normal direction of the surface of the substrate and has a field of view that overlaps the field of view of the plurality of tilt cameras on the surface of the substrate,
The control unit, based on the captured image captured by the facing camera and the captured image captured by the tilt camera while irradiating light from the projector to the measurement region, the tertiary of the measurement region The appearance inspection apparatus according to any one of claims 1 to 17, which measures an original shape.   The control unit, based on an image obtained by converting the captured image captured by the tilt camera into the coordinate system of the directly facing camera and the captured image captured by the directly facing camera, increases the height of the measurement region in each pixel. The appearance inspection apparatus according to claim 18, wherein the three-dimensional shape of the measurement region is measured by determining the length.   The appearance inspection apparatus according to any one of claims 1 to 19, wherein the control unit holds the measured three-dimensional shape of the measurement region as point cloud data. A step of setting a measurement area for the substrate;
Imaging the measurement region with an inclined camera arranged to be inclined with respect to the normal direction of the surface of the substrate while irradiating the measurement region with light, and obtaining a captured image;
And a step of measuring a three-dimensional shape of the measurement region based on the captured image.

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