CN110383001B - Appearance inspection device and appearance inspection method - Google Patents
Appearance inspection device and appearance inspection method Download PDFInfo
- Publication number
- CN110383001B CN110383001B CN201780087964.6A CN201780087964A CN110383001B CN 110383001 B CN110383001 B CN 110383001B CN 201780087964 A CN201780087964 A CN 201780087964A CN 110383001 B CN110383001 B CN 110383001B
- Authority
- CN
- China
- Prior art keywords
- solder
- irradiation
- substrate
- irradiation light
- unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
- Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
Abstract
The irradiation light (Li) is emitted to the surface (Bs) of the substrate (B) without directly irradiating the solder (S) with the irradiation light (Li), and the irradiation light (Li) reflected by the surface (Bs) is irradiated to the solder (S). The irradiation light (Li) irradiated to the solder (S) by the reflection of the solder (S) on the surface (Bs) is reflected by the steep slope (Ss) and then enters the camera (5), unlike the irradiation light (Li) directly irradiated to the solder (S). As a result, the steep slope (Ss) of the solder (S) can be imaged.
Description
Technical Field
The present invention relates to an appearance inspection technique for inspecting solder bonded to a substrate.
Background
Conventionally, in order to determine whether or not solder bonded to a substrate is good, an appearance inspection technique is used in which light is irradiated from above onto the solder and light reflected by the solder is imaged. For example, in patent document 1, lights (infrared, red, green, and blue) having different wavelengths are irradiated from obliquely upward at different angles from each other to the solder, and a camera facing the substrate captures an image of the light reflected by the solder. In this case, the incident angle to the substrate is set smaller as the light having a longer wavelength is, and the wavelength of the light reflected by the inclined surface of the solder and incident on the camera is different depending on the inclination of the inclined surface. As a result, the gentler the slope of the solder, the longer the wavelength of light is captured. Thus, the shape of the solder can be determined based on the image obtained by imaging the solder.
Documents of the prior art
Patent document
Patent document 1: japanese patent application laid-open No. 2010-71844
Disclosure of Invention
Technical problem to be solved by the invention
However, in the appearance inspection device of patent document 1, light is directly irradiated to solder provided on the surface of a substrate, and light reflected by the solder is imaged by a camera facing the surface of the substrate. In this configuration, as described above, light reflected by a slope gentler than a predetermined slope is incident on the camera, while light reflected by a slope steeper than a predetermined slope is not incident on the camera. Therefore, as shown in patent document 1, the steep slope of the solder near the element cannot be photographed by the camera and becomes dark. However, in order to determine that the state of the solder is good, it is preferable to confirm that the solder near the element is wet and forms a steep slope. Therefore, a technique capable of imaging a steep slope of a solder is desired.
The present invention has been made in view of the above-described problems, and an object thereof is to provide a technique capable of imaging a steep slope of a solder.
Technical solution for solving technical problem
The appearance inspection device of the present invention includes: a substrate holding section that holds a substrate having a surface provided with a solder bonding position at which solder is bonded; a first irradiation unit that irradiates the solder with irradiation light reflected by the surface of the substrate by emitting the irradiation light to the surface of the substrate; an imaging unit that images the solder in a manner facing the surface; and a control unit for inspecting the state of the solder based on the result of the image pickup of the solder by the image pickup unit.
The appearance inspection method of the present invention includes the steps of: irradiating irradiation light reflected by the surface to the solder by emitting the irradiation light to the surface of the substrate to which the solder is bonded at the solder bonding position; shooting the solder opposite to the surface of the substrate; and inspecting the state of the solder based on the result of photographing the solder.
In the present invention (appearance inspection apparatus, appearance inspection method) configured as described above, irradiation light is emitted to the surface of the substrate without directly irradiating the solder with the irradiation light, and the irradiation light reflected by the surface is irradiated to the solder. The irradiation light irradiated to the solder by reflection on the surface of the substrate is reflected by a steep slope and enters the imaging unit, compared with the irradiation light directly irradiated to the solder. As a result, the steep slope of the solder can be photographed.
The appearance inspection device may be configured such that the control unit inspects the state of the solder based on a result of checking whether or not a portion having a luminance equal to or higher than a predetermined threshold luminance is present on an image obtained by imaging the solder by the imaging unit. That is, when the solder is wet and the solder has a steep slope, the light reflected by the steep slope is incident on the imaging section. Therefore, by checking a portion where an image obtained by imaging the solder has a predetermined or higher brightness, it can be determined that the state of the solder is good.
In the appearance inspection device, the first irradiation unit may emit a predetermined projection pattern as irradiation light to the surface, the imaging unit may image an observation pattern included in the irradiation light reflected by the solder, and the control unit may determine the shape of the solder based on the observation pattern. In this configuration, the shape of the solder can be accurately determined.
Specifically, the appearance inspection apparatus may be configured such that the control unit determines the shape of the solder based on the difference between the shapes of the projection pattern and the observation pattern. In this case, the appearance inspection apparatus may be configured such that the projection pattern has a plurality of lines of different colors arranged at intervals. In this configuration, even when adjacent lines are close to each other in the observation pattern, the lines can be distinguished by the difference in color, and therefore the shape of the solder can be accurately determined.
The appearance inspection device may be configured such that the first irradiation unit irradiates the surface with 3 or more sinusoidal stripe patterns having different phases from each other as projection patterns, the imaging unit acquires observation patterns for the 3 or more sinusoidal stripe patterns, respectively, and the control unit obtains a correspondence between an incident position at which the irradiation light is incident on the surface and a reflection position at which the irradiation light is reflected by the solder based on the phases calculated by a phase shift method from the observation patterns, and obtains the shape of the solder based on the correspondence. In this configuration, the shape of the solder can be determined more accurately.
The appearance inspection apparatus may be configured such that a plurality of solder bonding positions are provided on the surface of the substrate, a plurality of irradiation ranges are set on the surface of the first irradiation unit so as to correspond to the plurality of solder bonding positions, and irradiation light is emitted to each of the plurality of irradiation ranges, whereby reflected light reflected in the irradiation ranges is irradiated to solder bonded to the solder bonding positions corresponding to the irradiation ranges. In this configuration, the steep slope of each of the plurality of solders can be photographed.
The appearance inspection device may be configured such that the first irradiation unit simultaneously irradiates irradiation light having different wavelengths to a plurality of specific irradiation ranges satisfying a predetermined positional relationship among the plurality of irradiation ranges, and the control unit associates the specific irradiation range from which the irradiation light is emitted with the solder that reflects the irradiation light reflected in the specific irradiation range, based on the wavelength of the irradiation light imaged by the imaging unit. In this configuration, the specific irradiation range can be accurately associated with the solder corresponding to the specific irradiation range in accordance with the wavelength of the irradiation light.
The appearance inspection device may further include a second irradiation unit configured to emit 3 or more light beams having different wavelengths from each other to the solder from different angles, and the control unit may inspect the state of the solder based on a result of the imaging unit imaging the 3 or more light beams reflected by the solder. This makes it possible to photograph a gentle slope of the solder.
The appearance inspection device is configured such that the first irradiation unit emits irradiation light to a wire provided on the surface of the substrate. In this configuration, the irradiation light applied to the solder is secured by reflection on the surface of the substrate, and the steep slope of the solder can be appropriately imaged.
Further, the appearance inspection device is configured to further include: a lens having an optical axis parallel to a normal line of a surface of the substrate and facing the substrate; and a beam splitter that guides the light emitted from the substrate and having passed through the lens to the imaging unit, and guides the light emitted from the first irradiation unit to the substrate via the lens. In this way, by making the imaging unit and the first irradiation unit share the lens, the range in which the imaging unit can image can be matched with the range in which the first irradiation unit can irradiate the irradiation light.
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, a steep slope of solder can be photographed.
Drawings
Fig. 1 is a diagram schematically showing an example of an appearance inspection apparatus according to the present invention.
Fig. 2 is a flowchart showing an example of an operation performed by the appearance inspection apparatus of fig. 1.
Fig. 3 is a flowchart showing a first operation example executed in the solder inspection process of the flowchart of fig. 2.
Fig. 4 is a view schematically showing a case where steep slope inspection of solder is performed according to the flowcharts of fig. 2 and 3.
Fig. 5 is a flowchart showing a second operation example executed in the solder inspection process of the flowchart of fig. 2.
Fig. 6 is a diagram schematically showing a first modification of the steep slope inspection of solder.
Fig. 7 is a diagram schematically showing a second modification of the steep slope inspection of solder.
Fig. 8 is a view schematically showing a third modification of the steep slope inspection of solder.
Detailed Description
Fig. 1 is a diagram schematically showing an example of an appearance inspection apparatus according to the present invention. The appearance inspection device 1 is a solder inspection device for determining whether or not the solder S bonded to the substrate B is good based on the appearance of the solder S, and includes a control unit 11 and a user interface 12. The control Unit 11 is a processor including a CPU (Central Processing Unit), a RAM (Random Access Memory), and the like, and controls the inspection of the solder S bonded to the substrate B. The user interface 12 is constituted by, for example, a touch panel, and the user can set the inspection condition of the solder S or confirm the inspection result of the solder via the user interface 12.
The appearance inspection apparatus 1 includes a substrate conveying unit 2 for conveying the substrate B, an inspection head H facing the substrate B from above, and a driving unit 3 for driving the inspection head H. The substrate conveying unit 2 is composed of, for example, a pair of conveyor belts, and fixes the substrate B carried in from the outside to a predetermined holding position (the position of the substrate B in fig. 1) or carries out the substrate B from the holding position to the outside. Electronic components are mounted on the surface Bs of the substrate B with solder S, and the substrate conveying unit 2 fixes the substrate B at the holding position in a state where the surface Bs of the substrate B is held horizontally. The driving unit 3 is composed of, for example, an XY robot, and drives the inspection head H two-dimensionally along the horizontal direction so that the inspection head H faces a predetermined inspection position of the substrate B held at the holding position.
The inspection head H includes an optical system 4, a camera 5 attached to the upper end of the optical system 4, a light 6 for a gentle slope provided around the optical system 4, and a light 7 for a steep slope attached to the side surface of the optical system 4.
The optical system 4 includes a lens 41 facing the substrate B from above, and a beam splitter 42 facing the substrate B with the lens 41 interposed therebetween. The lens 41 is a telecentric lens having an optical axis a orthogonal to the surface Bs of the substrate B (in other words, parallel to the normal Bn of the surface Bs) and having telecentricity at least on the substrate B side. The beam splitter 42 is, for example, a half mirror, and guides light emitted from the substrate B and transmitted through the lens 41 to the camera 5, while guiding light emitted from the steep illumination 7 to the substrate B through the lens 41.
The camera 5 includes a solid-state imaging Device 51 such as a CCD (Charge Coupled Device) sensor or a CMOS (Complementary MOS) sensor. The camera 5 uses the solid-state imaging device 51 to image the light from the substrate B imaged by the lens 41.
The illumination for gentle slope 6 has a circular ring shape centered on the optical axis a, and has a hollow portion 61 in a portion facing the optical system 4. The illumination for gentle slope 6 has 3 annular illuminations 62r, 62g, 62b arranged concentrically about the optical axis a. These ring lights 62r, 62g, and 62B have diameters that increase from small to large in this order, and emit light of different wavelengths (colors) from obliquely above the substrate B. Specifically, the annular illumination 62r disposed on the innermost side emits red light to the substrate B, the annular illumination 62g disposed on the outer side of the annular illumination 62r emits green light to the substrate B, and the annular illumination 62B disposed on the outer side of the annular illumination 62g emits blue light to the substrate B. Thus, the incident angle to the substrate B is set smaller as the light having a longer wavelength is.
The steep slope illumination 7 includes a light source 71 and a light modulator 72, and light emitted from the light source 71 is modulated by the light modulator 72. As the optical modulator 72, a liquid crystal panel, a DMD (Digital Mirror Device), or the like can be used. The light modulated by the light modulator 72 is reflected by the beam splitter 42, and then is irradiated to the surface Bs of the substrate B by the lens 41. The steep slope illumination 7 can selectively irradiate light only to a predetermined range in the surface Bs of the substrate B by adjusting the modulation of light by the light modulator 72.
Fig. 2 is a flowchart showing an example of an operation performed by the appearance inspection apparatus of fig. 1. Fig. 3 is a flowchart showing a first operation example executed in the solder inspection process of the flowchart of fig. 2. The flowcharts of fig. 2 and 3 are executed by the control unit 11. Fig. 4 is a view schematically showing a case where the solder steep slope inspection is performed according to the flowcharts of fig. 2 and 3.
As shown in fig. 4, a component E is mounted on the surface Bs of the substrate B with solder S. That is, on the surface Bs of the substrate B, the solder joint position Ps is provided adjacent to the component mounting position Pe, and the solder S joined to the solder joint position Ps electrically connects the electrode Ed of the component E disposed at the component mounting position Pe and the solder joint position Ps (terminal). Then, in the flowcharts of fig. 2 and 3, the fillet of the solder S is inspected.
As shown in fig. 2, in step S101, the substrate transfer unit 2 fixes the substrate B carried in from the outside to the holding position. Thereby, the surface Bs of the planar substrate B is held horizontally. In step S102, the driving unit 3 moves the camera 5 to the inspection position. Thereby, the solder S to be an inspection object in the surface Bs of the substrate B is in the visual field of the camera 5. Also, in step S103, a solder inspection process is performed.
As shown in fig. 3, in the solder inspection process, the ring lights 62r, 62g, and 62b of the illumination 6 for gentle slope simultaneously emit light toward the solder S (step S201). Thereby, the light from the ring lights 62r, 62g, 62b is directly irradiated to the solder S. The camera 5 takes an image of light that is totally reflected by the slope Sl of the solder S and imaged on the solid-state imaging element 51 by the lens 41 (step S202). At this time, the longer the wavelength of light, the smaller the incident angle to the surface Bs of the substrate B is set, and the wavelength of light reflected by the slope Sl of the solder S and incident on the camera 5 differs depending on the slope of the slope Sl. As a result, the gentler the slope Sl of the solder S, the longer the wavelength of light can be imaged.
Therefore, in step S203, the control unit 11 checks whether the solder S is good or not based on the shape of the slope Sl of the solder S calculated from the color distribution in the image captured by the camera 5. The check as to whether the quality is good can be performed appropriately based on the previously used standard. Incidentally, the light 6 for gentle slope directly irradiates light to the solder S from obliquely above. Therefore, of the light totally reflected by the slope Sl of the solder S, the light incident on the camera 5 through the lens 41 is totally reflected by the gentle slope Sg whose inclination angle α is smaller than a predetermined angle (45 degrees at maximum), and the light totally reflected by the steep slope Ss whose inclination angle α is equal to or larger than the predetermined angle is not incident on the lens 41. Here, the inclination angle α is an angle (acute angle) formed by the surface Bs of the substrate B and the slope Sl of the solder S. Therefore, in step S203, it is checked whether or not the shape of the gentle slope Sg of the solder S is good only.
In contrast, in steps S204 to S207, it is checked whether or not the shape of the steep slope Ss of the solder S is good. That is, the irradiation range Ri of the light irradiated from the steep slope illumination 7 is set based on the position of the gentle slope Sg of the solder S confirmed in the gentle slope inspection of step S203 (step S204). Specifically, a range of the surface Bs of the solder S on the opposite side of the element E with respect to the gentle slope Sg is set as the irradiation range Ri. In this way, the irradiation range Ri is set on the surface Bs of the substrate B exposed without being covered with the element E and the solder S.
In step S205, the illumination light Li is irradiated from the steep illumination 7 to the set illumination range Ri. As described above, the lens 41 has telecentricity on the substrate B side. Therefore, the irradiation range Ri is irradiated with the irradiation light Li parallel to the optical axis a of the lens 41 (in other words, the normal Bn of the surface Bs of the substrate B). Diffused light Ld diffused and reflected in the irradiation range Ri in the irradiation light Li is incident on the inclined surface Sl of the solder S.
In this way, in a state where the irradiation light Li (i.e., the diffused light Ld) diffusion-reflected in the irradiation range Ri is irradiated to the slope Sl of the solder S, the camera 5 takes an image of light totally reflected by the slope Sl of the solder S and imaged on the solid-state imaging element 51 by the lens 41 (step S206). Then, the control unit 11 checks whether the solder S is good or not based on the image captured by the camera 5 (step S207).
Incidentally, the lens 41 has a decentering property on the substrate B side, so the reflected light Lr of the irradiation light Li which is totally reflected only by the inclined surface Sl of the solder S and is incident on the lens 41 in parallel with the optical axis a is imaged on the solid-state imaging element 51 by the lens 41. On the other hand, the steep slope illumination 7 irradiates the slope Sl of the solder S with the irradiation light Li diffused and reflected on the surface Bs of the substrate B. Therefore, of the irradiation light Li (i.e., the diffused light Ld) irradiated to the inclined surface Sl of the solder S, the reflected light Lr totally reflected only by the steep inclined surface Ss whose inclination angle α is the predetermined angle or more is imaged on the solid-state imaging element 51 by the lens 41. In other words, if the image of the reflected light Lr is included in the image of the slope Sl of the solder S captured by the camera 5, it can be determined that a steep slope Ss exists on the slope Sl of the solder S. Therefore, in step S207, if there is a portion having a luminance equal to or higher than the predetermined threshold luminance Lth in the image of the slope Sl of the solder S captured by the camera 5, it is determined that the shape of the solder S is good, and if there is no portion having a luminance equal to or higher than the predetermined threshold luminance Lth, it is determined that the shape of the solder S is bad.
When the solder inspection processing is completed in this way, returning to fig. 1, it is determined whether or not the inspection of all the solder S on the substrate B is completed (step S104). When the solder S remains unchecked (no in step S104), the process returns to step S102, and the inspection head H moves above the solder S to be inspected next. On the other hand, when the inspection of all the solders S is completed (yes in step S104), the inspection result of each solder S is displayed on the user interface 12 (step S105), and the substrate B is carried out (step S106).
In the embodiment thus configured, in steps S204 to S207, the irradiation light Li is emitted toward the surface Bs of the substrate B, and the irradiation light Li reflected by the surface Bs is irradiated to the solder S, instead of being directly irradiated to the solder S. The irradiation light Li irradiated to the solder S via reflection of the surface Bs of the solder S in this way is incident to the camera 5 after being reflected by the steep slope Ss, unlike the irradiation light Li directly irradiated to the solder S. As a result, the steep slope Ss of the solder S can be imaged.
In this configuration, when the solder S is wet and the solder S has the steep slope Ss, the light reflected by the steep slope Ss is incident on the camera 5. Therefore, by checking that a portion having a luminance equal to or higher than a predetermined threshold luminance is present in the image obtained by imaging the solder S, it is possible to easily determine that the state of the solder S is good.
Further, the illumination 6 for a gentle slope is provided which emits 3 or more kinds of light having different wavelengths to the solder S from different angles, and the control unit 11 inspects the state of the solder S based on the result of the camera 5 capturing the 3 or more kinds of light reflected by the solder S. This also enables the gentle slope Sg of the solder S to be imaged.
The optical system 4 has an optical axis a parallel to a normal Bn to the surface Bs of the substrate B, faces the substrate B, and guides light emitted from the substrate B and passing through the lens 41 toward the camera 5 and light emitted from the steep-slope illumination 7 toward the substrate B through the lens 41 by the beam splitter 42. In this way, the lens 41 is commonly used in the camera 5 and the illumination for steep slope 7, whereby the range that can be photographed by the camera 5 (that is, the field of view of the camera 5) can be made to coincide with the range that can be irradiated with the irradiation light Li by the illumination for steep slope 7.
Fig. 5 is a flowchart showing a second operation example executed in the solder inspection process of the flowchart of fig. 2. The flowchart of fig. 5 is executed by the control of the control unit 11. In the following description, points different from the above-described embodiment will be mainly described, and common points are denoted by the same reference numerals and will not be described as appropriate. Further, since the configuration is common to the above-described embodiments, it is needless to say that the same effects are obtained.
In the flowchart of fig. 5, steps S201 to S203 are executed in the same manner as described above, an inspection is performed on the gentle slope Sg of the solder S, and in step S210, it is determined whether or not the inspection result of the gentle slope Sg is good. If the inspection result is defective (no in step S210), the inspection target solder S is determined to be defective (NG) (step S211), the flowchart of fig. 5 is ended, and the process returns to the flowchart of fig. 2.
On the other hand, when the inspection result is good (yes in step S210), steps S204 to S207 are executed as described above, the inspection is performed on the steep slope Ss of the solder S, and whether the inspection result of the steep slope Ss is good or not is determined in step S212. If the inspection result is poor (no in step S212), the NG determination is determined for the solder S to be inspected, whereas if the inspection result is good (yes in step S212), the OK determination is determined for the solder S to be inspected (OK) (step S213). Then, the flowchart of fig. 5 is ended, and the flow returns to the flowchart of fig. 2.
In this embodiment, when the inspection result of the gentle slope Sg of the solder S is poor, the inspection of the steep slope Ss of the solder S is omitted. Therefore, the inspection of the solder S can be performed efficiently.
However, in the above-described embodiment, the inspection of the steep slope Ss of the solder S is performed by confirming whether or not the captured image of the solder S includes the luminance of the threshold luminance or more. However, the specific inspection method of the steep slope Ss of the solder S is not limited to this, and various modifications can be made.
Fig. 6 is a diagram schematically showing a first modification of the steep slope inspection of solder. In this modification, the steep slope illumination 7 irradiates the irradiation range Ri with a projection pattern Ti having two reference lines I arranged with an interval Δ Ii therebetween as irradiation light Li. Further, in a state where the projection pattern Ti of the irradiation range Ri diffused reflection (i.e., the irradiation light Li) is irradiated to the slope Sl of the solder S, the camera 5 takes an image of light that is totally reflected by the steep slope Ss of the solder S and imaged on the solid-state imaging element 51 by the lens 41. Thereby, a pattern of the irradiation light Li totally reflected by the steep slope Ss of the solder S (i.e., the reflected light Lr) is photographed, that is, an observation pattern Tr having two reference lines I arranged with an interval Δ Ir therebetween.
At this time, the following relational expression holds between the reflection angle β of the diffused reflection of the projection pattern Ti in the irradiation range Ri and the inclination angle α of the steep slope Ss of the solder S.
β ═ arcsin (Δ Ir/Δ Ii) … formula 1
α ═ (90 ° + β)/2 … formula 2
That is, the controller 11 can calculate the inclination angle α of the gentle slope Sg existing on the slope Sl of the solder S based on the interval Δ Ii between the reference lines I on the projection pattern Ti and the interval Δ Ir between the reference lines I on the observation pattern Tr.
In this modification, the steep slope illumination 7 emits a predetermined projection pattern Ti as the irradiation light Li to the surface Bs of the substrate B, and the camera 5 images the observation pattern Tr included in the irradiation light Li reflected by the steep slope Ss of the solder S. Then, the controller 11 determines the shape of the solder S, specifically, the inclination angle α of the steep slope Ss, based on the difference between the shapes of the projection pattern Ti and the observation pattern Tr. This enables the shape of the solder S to be accurately determined.
At this time, for example, a steep slope Ss having a slope angle α equal to or larger than a predetermined threshold angle may be used as a criterion for determining whether the solder S is good. Thus, it is confirmed that the solder S is sufficiently wetted and the steep slope Ss is formed on the slope Sl of the solder S, and it is possible to determine whether the solder S is good or not.
Also, the projection pattern Ti may be configured with a plurality of reference lines I having colors different from each other. In this configuration, even when the adjacent reference lines I are close to each other in the observation pattern Tr, the control section 11 can distinguish the reference lines I from each other according to the color, and thus can accurately determine the shape of the solder S.
Fig. 7 is a diagram schematically showing a second modification of the steep slope inspection of solder. In this modification, as shown in the column of "projection/imaging" in fig. 7, the illumination 7 for steep slope is irradiated to the irradiation range Ri as the irradiation light Li in a sine wave stripe pattern Ts in which the intensity of light changes in a sine wave shape. Further, in a state where the sine wave stripe pattern Ts of the irradiation range Ri diffused reflection (i.e., the irradiation light Li) is irradiated to the slope Sl of the solder S, the camera 5 takes an image of light totally reflected by the steep slope Ss of the solder S and imaged on the solid-state imaging element 51 by the lens 41. Thereby, the observation pattern Tr, which is the pattern that the irradiation light Li (i.e., the reflected light Lr) totally reflected by the steep slope Ss of the solder S has, is photographed. Then, the observation pattern Tr is imaged for each sine wave stripe pattern Ts while changing the phase of the sine wave stripe pattern Ts to 0 °, 90 °, 180 °, 270 °. Thus, 4 observation patterns Tr having different phases shifted by 90 ° from each other are obtained.
Next, as shown in the column of "phase calculation" in fig. 7, the control unit 11 calculates the phase θ at each position (x, y) from the 4 observation patterns Tr by the phase shift method, and obtains the phase distribution. Here, x in parentheses represents an x-coordinate position in the xy-orthogonal coordinate system, and y in parentheses represents a y-coordinate position in the xy-orthogonal coordinate axis. Then, the controller 11 associates each position Di (x, y) on the sine-wave stripe pattern Ts irradiated to the irradiation range Ri with each position Dr (x, y) on the observation pattern Tr by using the phase θ. Specifically, the position Di (x, y) on the sine wave stripe pattern Ts and the position Dr (x, y) on the observation pattern Tr having the same phase θ are correlated. The phase θ of each position Di (x, y) on the sine wave stripe pattern Ts may be obtained from an image obtained by imaging each sine wave stripe pattern Ts irradiated to the irradiation range Ri by a phase shift method, or may be obtained from data used when the sine wave stripe pattern Ts is irradiated.
The position Di on the sine wave stripe pattern Ts and the position Dr on the observation pattern Tr thus established correspond to the outgoing point and the incoming point of the same reflected light Lr, respectively. That is, as shown in the column of "shape calculation" in fig. 7, the trajectory of reflected light Lr (i.e., diffused light Ld) that is diffused and reflected by the position Di of the irradiation range Ri and enters the steep slope Ss of the solder S is determined. Then, based on the reflection angle β of the reflected light Lr and the above equation 2, the inclination angle α of the steep slope Ss of the solder S at the position Di is obtained. The shape of the steep slope Ss of the solder S can be obtained by performing this calculation for each combination of the position Di and the position Dr.
In this modification, the steep slope illumination 7 irradiates 4 sine wave stripe patterns Ts different in phase from each other as projection patterns Ti onto the surface Bs of the substrate B, and the camera 5 acquires observation patterns Tr for the 4 sine wave stripe patterns Ts, respectively. Then, the controller 11 obtains a correspondence relationship between an incident position Di at which the irradiation light Li is incident on the surface Bs and a reflection position Dr at which the irradiation light Li is reflected by the solder S based on the phase θ calculated from the observation pattern Tr by the phase shift method, and obtains the shape of the solder S based on the correspondence relationship. In this configuration, the shape of the solder S can be determined more accurately.
In this case, for example, the presence of a steep slope Ss having an inclination angle α equal to or greater than a predetermined threshold angle in a range equal to or greater than a predetermined threshold area may be used as a criterion for determining whether the solder S is satisfactory. Thus, it is confirmed that the solder S is sufficiently wetted and a steep slope Ss is formed on the slope Sl of the solder S, and it is possible to determine whether the solder S is good or not.
Fig. 8 is a view schematically showing a third modification of the steep slope inspection of solder. In this modification, a plurality of (3) irradiation ranges Ri are set on the surface Bs of the substrate B corresponding to a plurality of (3) solder bonding positions Ps. Then, by simultaneously emitting the irradiation light Li to the plurality of irradiation ranges Ri, the irradiation light Li reflected in the irradiation ranges Ri is irradiated to the solder S bonded to the solder bonding position Ps corresponding to the irradiation ranges Ri. The camera 5 simultaneously images the slope Sl of each solder S, and the control unit 11 determines whether the solder S is good or not based on the imaging result. In this configuration, it is possible to simultaneously determine whether the solder S is good or not for a plurality of solders S, and it is possible to efficiently perform the inspection of the solder S.
Further, the steep slope illumination 7 simultaneously emits the illumination light Li different in wavelength (color) from each other to a plurality (2) of specific illumination ranges Rs satisfying a predetermined positional relationship among the plurality of illumination ranges Ri. Here, the predetermined positional relationship may be, for example, a relationship in which a distance between the two is smaller than a predetermined threshold distance. The control unit 11 associates a specific irradiation range Rs from which the irradiation light Li is emitted with the solder S that reflects the irradiation light Li reflected in the specific irradiation range Rs, based on the wavelength (color) of the irradiation light Li captured by the camera 5. In this configuration, the specific irradiation range Rs and the solder S corresponding to the specific irradiation range Rs can be accurately associated with each other in accordance with the wavelength (color) of the irradiation light Li.
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 substrate conveying unit 2 corresponds to an example of the "substrate holding unit" of the present invention, the steep slope illumination 7 corresponds to an example of the "first illuminating unit" of the present invention, the camera 5 corresponds to an example of the "imaging unit" of the present invention, the control unit 11 corresponds to an example of the "control unit" of the present invention, the substrate B corresponds to an example of the "substrate" of the present invention, the surface Bs corresponds to an example of the "surface" of the present invention, the solder bonding position Ps corresponds to an example of the "solder bonding position" of the present invention, the solder S corresponds to an example of the "solder" of the present invention, the irradiation light Li corresponds to an example of the "irradiation light" of the present invention, and the projection pattern Ti corresponds to an example of the "projection pattern" of the present invention, the observation pattern Tr corresponds to an example of the "observation pattern" of the present invention, the sine wave stripe pattern Ts corresponds to an example of the "sine wave stripe pattern" of the present invention, the reference line I corresponds to an example of the "line" of the present invention, the interval Δ Ii corresponds to an example of the "interval" of the present invention, the position Di corresponds to an example of the "incident position" of the present invention, the position Dr corresponds to an example of the "reflection position" of the present invention, the irradiation range Ri corresponds to an example of the "irradiation range" of the present invention, the specific irradiation range Rs corresponds to an example of the "specific irradiation range" of the present invention, the soft-slant-surface illumination 6 corresponds to an example of the "second irradiation section" of the present invention, the lens 41 corresponds to an example of the "lens" of the present invention, and the optical axis a corresponds to an example of the "optical axis" of the present invention, the normal line Bn corresponds to an example of the "normal line" of the present invention, the beam splitter 42 corresponds to an example of the "beam splitter" of the present invention, and the threshold luminance Lth corresponds to an example of the "threshold luminance" of the present invention.
The present invention is not limited to the above-described embodiments, and various modifications can be made to the above-described embodiments without departing from the spirit thereof. For example, in the above embodiment, the lens 41 is commonly used in the camera 5 and the illumination 7 for steep slope. However, lenses may be separately provided on the camera 5 and the steep slope illumination 7, respectively.
Further, the specific configuration of the steep slope illumination 7 may be changed as appropriate. For example, the steep slope illumination 7 can adjust the irradiation position of the irradiation light Li by modulating light with the light modulator 72. However, the steep slope illumination 7 may be configured so that light from the light source 71 is converged by a lens without passing through the light modulator 72. In this case, the position of the inspection head H can be controlled so that the light converging range coincides with the irradiation range Ri, whereby the inspection of the solder S can be performed.
In addition, the position of the surface Bs of the substrate B to which the light Li is irradiated may be appropriately changed. For example, in fig. 8, on the surface Bs of the substrate B, the text "ABCD" is marked with a thread (silk) K. Therefore, the steep slope illumination 7 may be configured to emit the irradiation light Li to the wire K. That is, the filament K having a white color can efficiently diffuse the irradiation light Li. Therefore, the irradiation light Li irradiated to the solder S is secured through the reflection of the wire K, and the steep slope Ss of the solder S can be appropriately photographed.
The structure of the lens 41 may be appropriately changed. For example, the lens 41 may be configured to have telecentricity on both sides thereof. Alternatively, a lens having no telecentricity may be used as the lens 41.
In step S204, the irradiation range Ri is set based on the position of the gentle slope Sg of the solder S confirmed by the gentle slope check. However, the irradiation range Ri may be set based on data indicating the position of the solder bonding position Ps.
In the first modification of the steep slope inspection of solder, the number of reference lines I included in the projected pattern Ti is not limited to two, and may be 3 or more. In this case, the inclination angle α of each of the plurality of positions on the steep slope Ss of the solder S can be obtained by applying the relationship of the expressions 1 and 2 to the two adjacent reference lines I.
In addition, the number of the sine wave stripe patterns Ts irradiated in the second modification of the steep slope inspection of solder is not limited to 4. That is, the phase θ may be obtained by a phase shift method by irradiating 3 or more sinusoidal fringe patterns Ts having different phases from each other.
In the third modification of the steep slope inspection of solder, the positional relationship as a reference for setting the specific irradiation range Rs is not limited to the reference based on the distance. For example, a plurality of irradiation ranges Ri that have the same positional relationship with the corresponding element E, in other words, are disposed on the same side with respect to the element E may be set as the specific irradiation range Rs. Alternatively, a plurality of irradiation ranges Ri in a relationship satisfying both the reference based on the distance and the reference based on the positional relationship with the element E here may be set as the specific irradiation range Rs.
Further, the configuration of the light 6 for gentle slope can be appropriately changed. For example, the heights of the ring lights 62r, 62g, 62b may be changed, respectively. Alternatively, 4 or more lights having different wavelengths from each other may be emitted from the illumination for oblique surface 6.
In addition, the arrangement of the inspection head H can be changed as appropriate. Therefore, the surface Bs of the substrate B may be disposed downward, and the inspection head H may be configured to face the surface Bs of the substrate B from below.
Description of the reference numerals
1 … appearance inspection device, 11 … control unit, 12 … user interface, 2 … substrate transfer unit (substrate holding unit), 4 … optical system, 41 … lens, 42 … beam splitter, 5 … camera (imaging unit), 51 … solid-state imaging element, 6 … illumination for gentle slope (second irradiation unit), 7 … illumination for steep slope (first irradiation unit), 71 … light source, 72 … light modulator, a … optical axis, B … substrate, Bs … surface, Bn … normal, Di … position (incident position), Dr … position (reflection position), E … element, Ed … electrode, H … inspection head, I … reference line (line), Δ Ii … interval, Δ Ir … interval, K … wire, Li … irradiation light, Ld … diffusion light, Lr …, Lth … threshold brightness, … junction position, peri 72 irradiation range specific irradiation range …, and reflected light 3653 diffusion light …, S … solder, Sl … slope, Sg … gentle slope, Ss … steep slope, Ti … projection pattern, Tr … observation pattern, Ts … sine wave stripe pattern, α … inclination angle, β … reflection angle.
Claims (11)
1. An appearance inspection device is provided with:
a substrate holding section that holds a substrate having a surface provided with a solder bonding position at which solder is bonded;
a first irradiation unit that irradiates the solder with irradiation light reflected by the surface of the substrate by emitting the irradiation light to the surface;
an imaging unit that images the solder in a manner facing the surface; and
a control section for checking the state of the solder based on the result of the image pickup of the solder by the image pickup section,
the first irradiation unit emits a predetermined projection pattern as the irradiation light to the surface,
the imaging unit images an observation pattern of the irradiation light reflected by the solder,
the control unit determines the shape of the solder based on the observation pattern.
2. The visual inspection device according to claim 1,
the control unit checks the state of the solder based on a result of checking whether or not a portion having a luminance equal to or higher than a predetermined threshold luminance is present on an image obtained by imaging the solder by the imaging unit.
3. The appearance inspection device according to claim 1 or 2,
the control unit determines the shape of the solder based on a difference between the shapes of the projected pattern and the observed pattern.
4. The visual inspection device according to claim 3,
the projection pattern has a plurality of lines of different colors arranged at intervals.
5. The visual inspection device according to claim 1,
the first irradiation section irradiates more than 3 sine wave stripe patterns with different phases as the projection pattern on the surface,
the imaging unit acquires the observation patterns for each of the 3 or more sine wave stripe patterns,
the control unit obtains a correspondence between an incident position at which the irradiation light is incident on the surface and a reflection position at which the irradiation light is reflected by the solder, based on a phase calculated by a phase shift method from the observation pattern, and obtains a shape of the solder based on the correspondence.
6. An appearance inspection device is provided with:
a substrate holding section that holds a substrate having a surface provided with a solder bonding position at which solder is bonded;
a first irradiation unit that irradiates the solder with irradiation light reflected by the surface of the substrate by emitting the irradiation light to the surface;
an imaging unit that images the solder in a manner facing the surface; and
a control section for checking the state of the solder based on the result of the image pickup of the solder by the image pickup section,
a plurality of said solder bonding locations are provided on said surface of said substrate,
the first irradiation unit sets a plurality of irradiation ranges on the surface in correspondence with the plurality of solder bonding positions, and irradiates the reflected light reflected in the irradiation ranges to the solder bonded to the solder bonding position corresponding to the irradiation range by emitting the irradiation light to each of the plurality of irradiation ranges.
7. The visual inspection device of claim 6,
the first irradiation unit simultaneously emits the irradiation light having different wavelengths to a plurality of specific irradiation ranges satisfying a predetermined positional relationship among the plurality of irradiation ranges,
the control unit associates the specific irradiation range from which the irradiation light is emitted with the solder that reflects the irradiation light reflected in the specific irradiation range, based on the wavelength of the irradiation light captured by the imaging unit.
8. An appearance inspection device is provided with:
a substrate holding section that holds a substrate having a surface provided with a solder bonding position at which solder is bonded;
a first irradiation unit that irradiates the solder with irradiation light reflected by the surface of the substrate by emitting the irradiation light to the surface;
an imaging unit that images the solder in a manner facing the surface;
a control unit for inspecting the state of the solder based on the result of the image pickup of the solder by the image pickup unit; and
a second irradiation unit which emits 3 or more lights having different wavelengths to the solder from different angles,
the control unit checks the state of the solder based on a result of the image pickup unit picking up the 3 or more lights reflected by the solder.
9. An appearance inspection device is provided with:
a substrate holding section that holds a substrate having a surface provided with a solder bonding position at which solder is bonded;
a first irradiation unit that irradiates the solder with irradiation light reflected by the surface of the substrate by emitting the irradiation light to the surface;
an imaging unit that images the solder in a manner facing the surface; and
a control section for checking the state of the solder based on the result of the image pickup of the solder by the image pickup section,
the first irradiation unit emits the irradiation light to a wire provided on the surface of the substrate.
10. An appearance inspection device is provided with:
a substrate holding section that holds a substrate having a surface provided with a solder bonding position at which solder is bonded;
a first irradiation unit that irradiates the solder with irradiation light reflected by the surface of the substrate by emitting the irradiation light to the surface;
an imaging unit that images the solder in a manner facing the surface;
a control unit for inspecting the state of the solder based on the result of the image pickup of the solder by the image pickup unit;
a lens having an optical axis parallel to a normal line of the surface of the substrate and facing the substrate; and
and a beam splitter that guides the light emitted from the substrate and having passed through the lens to the imaging unit, and guides the light emitted from the first irradiation unit to the substrate via the lens.
11. An appearance inspection method includes the steps of:
irradiating a predetermined projection pattern reflected by a surface of a substrate to which solder is bonded at a solder bonding position, to the solder by projecting the predetermined projection pattern onto the surface;
photographing an observation pattern of the predetermined projection pattern reflected by the solder by photographing the solder so as to face the surface of the substrate; and
the state of the solder is checked by finding the shape of the solder based on the observation pattern.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/JP2017/008976 WO2018163278A1 (en) | 2017-03-07 | 2017-03-07 | Appearance inspection device and appearance inspection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110383001A CN110383001A (en) | 2019-10-25 |
| CN110383001B true CN110383001B (en) | 2020-12-25 |
Family
ID=63449039
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201780087964.6A Active CN110383001B (en) | 2017-03-07 | 2017-03-07 | Appearance inspection device and appearance inspection method |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP6733039B2 (en) |
| CN (1) | CN110383001B (en) |
| WO (1) | WO2018163278A1 (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09196860A (en) * | 1996-01-22 | 1997-07-31 | Shimu:Kk | Method for checking soldering state |
| JP2001183306A (en) * | 1999-12-22 | 2001-07-06 | Yokogawa Electric Corp | Apparatus for inspecting solder joined part |
| JP2001324455A (en) * | 2000-05-15 | 2001-11-22 | Device Link:Kk | Visual inspection apparatus for mounting substrate |
| CN1661323A (en) * | 2004-02-27 | 2005-08-31 | 欧姆龙株式会社 | Apparatus for surface inspection and method and apparatus for inspecting substrate |
| JP2006029829A (en) * | 2004-07-12 | 2006-02-02 | Shinshu Univ | Three-dimensional measuring instrument |
| JP2008309580A (en) * | 2007-06-13 | 2008-12-25 | Omron Corp | Inspection method of solder fillet and substrate appearance inspection apparatus |
| CN106030240A (en) * | 2014-01-08 | 2016-10-12 | 雅马哈发动机株式会社 | Visual inspection device and visual inspection method |
-
2017
- 2017-03-07 CN CN201780087964.6A patent/CN110383001B/en active Active
- 2017-03-07 JP JP2019504163A patent/JP6733039B2/en active Active
- 2017-03-07 WO PCT/JP2017/008976 patent/WO2018163278A1/en active Application Filing
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09196860A (en) * | 1996-01-22 | 1997-07-31 | Shimu:Kk | Method for checking soldering state |
| JP2001183306A (en) * | 1999-12-22 | 2001-07-06 | Yokogawa Electric Corp | Apparatus for inspecting solder joined part |
| JP2001324455A (en) * | 2000-05-15 | 2001-11-22 | Device Link:Kk | Visual inspection apparatus for mounting substrate |
| CN1661323A (en) * | 2004-02-27 | 2005-08-31 | 欧姆龙株式会社 | Apparatus for surface inspection and method and apparatus for inspecting substrate |
| JP2006029829A (en) * | 2004-07-12 | 2006-02-02 | Shinshu Univ | Three-dimensional measuring instrument |
| JP2008309580A (en) * | 2007-06-13 | 2008-12-25 | Omron Corp | Inspection method of solder fillet and substrate appearance inspection apparatus |
| CN106030240A (en) * | 2014-01-08 | 2016-10-12 | 雅马哈发动机株式会社 | Visual inspection device and visual inspection method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110383001A (en) | 2019-10-25 |
| JPWO2018163278A1 (en) | 2019-11-07 |
| JP6733039B2 (en) | 2020-07-29 |
| WO2018163278A1 (en) | 2018-09-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6287360B2 (en) | Inspection device | |
| JP3878023B2 (en) | 3D measuring device | |
| KR101207198B1 (en) | Board inspection apparatus | |
| JP4719284B2 (en) | Surface inspection device | |
| KR101659302B1 (en) | Three-dimensional shape measurement apparatus | |
| KR20160007361A (en) | Image capturing method using projecting light source and image capturing device using the method | |
| JP2001255281A (en) | Inspection apparatus | |
| JP6322335B2 (en) | Appearance inspection device | |
| JP2017538117A5 (en) | ||
| TWI773032B (en) | An arched illumination device, an imaging system with the same and a method for imaging | |
| US10186025B2 (en) | Inspection system and method for defect analysis of wire connections | |
| KR20060053847A (en) | Method for inspecting defects of glass plate and apparatus thereof | |
| JP4877100B2 (en) | Mounting board inspection apparatus and inspection method | |
| JP2000065758A (en) | Apparatus and method for inspection of cream solder piece on printed circuit board | |
| JP2019158393A (en) | Image inspection device | |
| KR20150022352A (en) | Inspection method of solder joint | |
| JP2015127689A (en) | Appearance inspection device | |
| KR101124567B1 (en) | Wafer inspecting apparatus having hybrid illumination | |
| CN110383001B (en) | Appearance inspection device and appearance inspection method | |
| JP2013015328A (en) | Display panel inspection device and display panel inspection method | |
| KR20080088946A (en) | Apparatus for inspection of three-dimensional shape and method for inspection by the same | |
| JP4205220B2 (en) | Appearance inspection method and apparatus | |
| JP2014222221A (en) | Inspection device of luminous body | |
| JP2012169370A (en) | Display panel inspection equipment and display panel inspection method | |
| JP3341739B2 (en) | Bump apex detection method and bump height measurement method and apparatus using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |