WO2009122765A1

WO2009122765A1 - Side-viewing optical member and image processing system

Info

Publication number: WO2009122765A1
Application number: PCT/JP2009/051284
Authority: WO
Inventors: 潤北村
Original assignee: マイクロ・スクェア株式会社
Priority date: 2008-03-31
Filing date: 2009-01-27
Publication date: 2009-10-08

Abstract

A side-viewing optical member (21, 100, 101) which enables easy verification of plural mounted portions formed across the full width of the side edge of an electronic component comprises a reflective surface (101A) facing one side edge of an electronic component (11) mounted on a substrate (11a) across the full width of the side edge. The side-viewing optical member is provided with a reflective member (14d) for adjusting the angle, which is swingably supported around a swing shaft (14g), and an angle adjusting mechanism (16) for swinging the reflective member (14d) around the swing shaft (14g), and can change an imaging region of the mounted portions by swinging the reflective member (14d).

Description

Side-viewing optical member and image processing system

The present invention relates to a side-viewing optical member for confirming a mounting portion formed between a substrate and an electronic component such as a so-called BGA (Ball Grid Array) package mounted on the substrate. The present invention relates to an image processing system provided.

Conventionally, a scope is used to check the BGA package mounting part. This scope includes a side-viewing prism having a reflecting surface facing a portion to be inspected of the BGA package, and an imaging unit including a CCD camera.

According to the scope having the above-described configuration, the imaging unit is disposed on the BGA package substrate via the side-viewing prism in a state where the side-viewing prism is disposed so as to face the inspection target portion of the BGA package mounted on the substrate. The mounting part is imaged. This known scope is disclosed in Patent Document 1.
JP 2001-108918 A

In a conventionally known scope, the imaging unit and the side viewing prism are integrally configured, and the user grasps the scope and moves it with respect to the side edge of the BGA package, thereby confirming the mounting part. It is carried out. However, since the side-viewing prism is narrower than the side edge of the BGA package, the side-viewing prism is used to inspect all the mounting parts formed over the entire width of the side edge. It is necessary to inspect each time by sequentially shifting along the side edge of the BGA package, and it is necessary to make settings such as alignment each time the inspection site is changed.

Further, since the side viewing prism is moved along the side edge in a state of being close to the side edge of the BGA package, if the imaging unit and the side viewing prism are displaced from the path to be moved, depending on the case. There is a risk of damaging or destroying the BGA package.

Furthermore, it is desirable to configure the side viewing prism as small as possible in consideration of movement, but if the size is reduced, the viewing angle becomes small. For this reason, it becomes difficult to image the mounting portion of the BGA package, that is, the entire ball.

In view of the above, the present invention provides a side-viewing optical member that can easily check a plurality of mounting portions formed over the entire width of a side edge of an electronic component and a part thereof. An object of the present invention is to provide an image processing system including the optical member.

In order to achieve the above object, the side-viewing optical member of the first configuration of the present invention has a reflective surface that faces the side edge over the entire width of one side edge of the electronic component mounted on the substrate. It is characterized by that.

To achieve the above object, the optical member for side viewing according to the second configuration of the present invention includes a pair of prisms and a holder that holds the prisms at a predetermined interval, and the prisms are inclined. A bottom surface and a horizontal top surface are formed, and the bottom surface is formed as a reflecting surface that is lowered toward the opposing prism side, and the reflecting surface faces the side edge over the entire width of one side edge of the electronic component. The light that is formed and is incident from the upper surface of one of the pair of prisms is reflected to the other prism at the bottom surface of the prism.
In the optical member for side view according to the present invention, preferably, the holder includes a fixing portion attached to each of the pair of prisms, and an adjustment portion that adjusts a distance between the fixing portions.
For example, the adjustment unit includes a bar fixed to one fixing unit and slidably connected to the other fixing unit, and the other fixing unit is guided by the bar and moved, thereby separating the pair of prisms from each other. Changes. The adjustment unit includes a pair of arms whose base end portions are rotatably attached to the respective fixed portions and whose tip portions are slidably connected to the other fixed portions, and the arms rotate at an intermediate portion in the longitudinal direction. It is connected via a shaft, and a pair of arms may be configured to expand and contract in a pantograph manner so that the interval between the pair of prisms is changed.

In order to achieve the other object, an image processing system according to the present invention includes a side-viewing optical member, an imaging unit provided on the other prism, and a processing unit that processes an image captured by the imaging unit. The electronic component mounted on the substrate is disposed between the bottom surfaces of the pair of prisms, the light from the light source provided on the upper side of the one prism is reflected by the bottom surface of the one prism, and the electronic component is mounted. By passing through the gap of the part and entering the other prism, the imaging unit takes an image of the mounting part of the electronic component while being back-lit by the light source, and the processing unit processes the image of the mounting part. It is said.

In the image processing system of the present invention, the image of the mounting part imaged by the imaging unit is obtained as a black and white image by back illumination with a light source, for example, and the gap between the balls is white and the ball and the foreign object are imaged black. .

According to the first configuration of the side-viewing optical member of the present invention, the side-viewing optical member is disposed so as to face the entire width of the side edge of the electronic component to be observed. Once the member is positioned with respect to the electronic component, it is not necessary to position the member with respect to the electronic component. As a result, the imaging unit is moved along the side edge of the electronic component above the side-viewing optical member, so that the imaging unit is provided along the side edge of the electronic component mounted on the substrate. It is possible to accurately scan all the balls that have been played. In particular, in the conventional scope, in order to thoroughly inspect a plurality of balls of the entire width at one side edge of an electronic component, it is necessary to change the position of the scope many times. For example, if the side-viewing optical member surrounds all the side edges of the electronic component and the imaging unit moves along the upper surface of the side-viewing optical member, all of the electronic components provided along all the side edges of the electronic component Since an enlarged image of the ball can be obtained, the conventional troublesome work can be eliminated.
Further, according to the first configuration and the second configuration of the side viewing optical member of the present invention, the side viewing optical member facing the side edge of the electronic component is fixedly arranged. In addition, the side-viewing optical member does not accidentally touch the side edge of the electronic component and damage or destroy the electronic component.
Further, since the imaging unit that moves during scanning does not include the side-viewing optical member, the weight of the entire imaging unit is reduced, and the driving means for moving the imaging unit can be reduced in size and the cost can be reduced. .

When the side-viewing optical member is disposed so as to face two side edges of the electronic component, or when it is placed so as to face all side edges of the electronic component, the side-viewing optical The number of positioning of the member with respect to the side edge of the electronic component is reduced. Accordingly, it is possible to confirm the mounting portion of the electronic component to be observed in a shorter time.
An angle adjusting reflecting member that is supported so as to be swingable around a swinging axis parallel to the side edge of the corresponding electronic component, and an angle at which the reflecting member swings around the swinging axis. And an adjustment mechanism, the angle adjustment reflection member is swung by the angle adjustment mechanism, and is incident on the angle adjustment reflection member from the side edge of the electronic component through the side viewing optical member. The optical axis can be shaken.
Therefore, even if the viewing angle with respect to the mounting portion of the side edge of the electronic component of the imaging unit is narrow, that is, the side-viewing optical member is small, the optical axis is swung by swinging the angle-adjusting reflecting member. It is possible to observe the entire mounting part.
The side-viewing optical member is composed of a prism having a total reflection surface facing the side edge of the electronic component, and the exit surface facing the imaging unit of the prism corresponds to the swing of the angle-adjusting reflection member. When the angle adjustment reflecting member is enlarged, the optical axis incident on the angle adjustment reflecting member from the side edge of the electronic component through the side viewing optical member is swung by the swing of the angle adjusting reflecting member. Even so, the light from the side edge of the electronic component is reliably incident on the imaging unit through the side-viewing optical member.
A wedge prism disposed between the side-viewing optical member and the corresponding side edge of the electronic component is provided, and the wedge prism is formed so as to gradually increase in thickness from the optical axis toward one side. In this case, even if the viewing angle with respect to the mounting portion on the side edge of the electronic component of the imaging unit is narrow, that is, the optical member for side view is small, the optical path on the electronic component side is shifted from the wedge prism to one side. Thus, it is possible to reliably observe the main parts of the mounting part, particularly on the electronic component side and the board side.
When the reflecting surface of the optical member for side view has an inclination angle larger than 45 degrees with respect to the corresponding side edge of the electronic component, the optical path on the electronic component side from the reflecting surface is opposite to the one side. It is possible to reliably observe the main part of the mounting part on the electronic component side.
When the reflective surface of the side-viewing optical member is formed in a convex shape toward the corresponding side edge of the electronic component and the imaging unit, the viewing angle with respect to the mounting portion of the side edge of the electronic component of the imaging unit is narrow. In other words, even if the side-viewing optical member is small, the entire mounting portion can be reliably observed by enlarging the optical path on the electronic component side from the reflecting surface.
Furthermore, according to the image processing system of the present invention, since the mounting portion as the observation portion is imaged by the imaging portion in a back-illuminated state and obtained as a so-called binary black and white image, image processing is easy. As this image processing, it is possible to detect the pitch interval and height of the balls and the foreign matter between the balls.

It is a schematic perspective view which shows the structure of the mounting part confirmation scope of the electronic component which concerns on 1st Embodiment of this invention. FIG. 2 is a perspective view of a prism device in the electronic component mounting portion confirmation scope of FIG. 1. (A) is a schematic front view which shows the optical system of the mounting part confirmation scope of the electronic component of FIG. 1, (B) is a schematic side view. It is a perspective view which simplifies and shows the optical system of the scope for electronic component mounting part confirmation of FIG. FIG. 2 is a front view showing in detail a swing mechanism of the electronic component mounting portion confirmation scope of FIG. 1. It is an enlarged view which shows the principal part of the scope for electronic component mounting part confirmation according to the second embodiment of the present invention. It is an enlarged view which shows the principal part of the scope for electronic component mounting part confirmation according to the third embodiment of the present invention. It is an enlarged view which shows the principal part of the scope for electronic component mounting part confirmation according to the fourth embodiment of the present invention. It is a perspective view which shows the lens apparatus for mounting part confirmation of the electronic component which concerns on 5th Embodiment of this invention. (A) is a top view which shows the prism which concerns on 5th Embodiment of this invention, (B) is a side view, (C) is a front view. It is a top view for demonstrating the shape of the prism used for the lens apparatus which concerns on 5th Embodiment. It is a figure for demonstrating the usage method of a prism apparatus in 5th Embodiment. It is the schematic which shows the image of the mounting part observed with the usage method shown in FIG. It is a perspective view which shows the lens apparatus for mounting part confirmation of the electronic component which concerns on 6th Embodiment of this invention. It is a perspective view which shows the lens apparatus for mounting part confirmation of the electronic component which concerns on the modification of 6th Embodiment of this invention. It is a figure which shows the image processing system which concerns on 7th Embodiment of this invention. It is a figure which shows the example of an image of the observation part which the imaging part in the image processing system of FIG. 16 imaged. It is a figure which shows the example of an image of the observation part which the imaging part in the image processing system of FIG. 16 imaged. It is a figure for demonstrating operation | movement of the process part in the image processing system of FIG. (A) is a front view which shows the prism which concerns on other embodiment of this invention, (B) is a side view.

Explanation of symbols

10, 20, 30, 40 Electronic component mounting part confirmation scope 11 BGA package 11a Substrate 11b Ball (mounting part)
12 stage 12A X stage 12B Y stage 12C 1st drive mechanism 12D 2nd drive mechanism 12E Prop 12F Bracket 14 Imaging unit 14a Imaging element 14b Optical system 14c Lens 14d, 14e Relay prism 14f Light source 14g Oscillating shaft 15 Display unit 16 Oscillating Mechanism 17 Lever 17a First arm 17b Second arm 18 Spring 18a One end 18b Other end 19 Pushing screw 21 Side view mirror (side view optical member)
22 Angle adjustment mirror 23 Fixed mirror 25 Housing 31 Wedge prism 43A Reflecting surface 100 Prism device (optical member for side view)
101, 110A, 110B Prism (optical member for side view)
101A Reflective surface 101B Upper surface

101C Side surface

100A, 100B, 100C Electronic device mounting part confirmation lens device 111 Prism bottom surface 112 Prism side surface 113 Prism upper surface 120

Holder

121A,

121B Fixing portion

122A, 122B Connecting portion 123 Insertion hole 125 Through Hole 130 First illumination unit 131 Second illumination unit 140

Observation unit

150, 150A Adjustment unit 151

Lock screw

153A, 153B Arm 154

Lock pin

155A, 155B Rail member 156 Rotating shaft 200 Image processing system 210 Imaging unit 220 Processing unit 230 Light source L1 BGA Long side of package L2 Short side of BGA package U1 First prism unit U2 Second prism unit

Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.
[First Embodiment]
FIG. 1 shows a configuration of a scope 10 for checking a mounting portion of an electronic component according to the first embodiment of the present invention. The scope 10 includes a stage 12 that supports a substrate 11a on which a BGA package 11 as an electronic component is mounted, and a prism unit (side view) for mounting portion confirmation that is disposed to face a side edge of the BGA package 11 on the substrate 11a. Optical member) 100 and an imaging unit 14 supported so as to be relatively movable with respect to the upper surface of the prism device 100. In the case shown in the drawing, an imaging signal captured by the imaging unit 14 is displayed on the display unit. 15 to display the image.

The stage 12 has a known configuration, and moves the substrate 11a, the BGA package 11 mounted on the substrate 11a, and the prism device 100 mounted on the substrate 11a in two horizontal directions orthogonal to each other, that is, the X direction and the Y direction. It is configured to let you. The illustrated stage 12 includes an X stage 12A movable in the X direction, a Y stage 12B mounted on the X stage 12A and movable in the Y direction, and a first drive mechanism 12C for moving the X stage. And a second drive mechanism 12D for moving the Y stage. However, the stage is not limited to that of the present embodiment.

As shown in FIG. 2, the prism device 100 is formed so as to face all the side edges of the BGA package 11. That is, the prism device 100 is configured in a frame shape by combining the four prisms 101 so as to surround the BGA package 11 whose outer shape in plan view is a quadrangle. One prism 101 is formed to face one side edge of the BGA package 11. Specifically, as shown in FIG. 3A, each prism 101 is formed in a trapezoidal shape with a cross section being vertically long, and a mounting portion between the side edge of the BGA package 11 and the substrate 11a, that is, a ball 11b. The reflecting surface 101A and the horizontal upper surface 101B are disposed so as to be inclined at an angle of 40 to 50 degrees, for example, 45 degrees. Further, as shown in FIG. 3B, each prism 101 is formed wide so as to face the entire width of one side edge of the BGA package 11. These prisms 101 are made of a transparent material such as quartz, transparent resin, or glass.

As shown in FIG. 3, the imaging unit 14 includes an imaging element 14a and an optical system 14b. The image sensor 14a is composed of, for example, a CCD, and accumulates light incident on the imaging surface and converts it into an electrical signal, thereby capturing an image formed on the imaging surface and outputting it as an image signal.

In the illustrated case, the optical system 14b includes a lens 14c made of, for example, a zoom lens, and a pair of relay prisms 14d and 14e for bending the optical path. The optical system 14b guides light incident from the BGA package 11 through the prism device 100 to the image sensor 14a. The relay prisms 14d and 14e of the optical system 14b are selected so that the width W2 along the width direction of the prism 101 covers the optical path of the lens 14c, as shown in FIG. 3B. Therefore, these relay prisms 14 d and 14 e are formed narrower than the width W 1 of the prism 101.

Furthermore, the optical system 14b is opposed to the upper surface 101B of the prism 101, and has a pair of light sources 14f on both sides of the relay prism 14d in a direction parallel to the side edge of the BGA package 11 (in the direction of arrow A in FIG. 3B). It has. These light sources 14f are composed of, for example, one or more LEDs, and illuminate the vicinity of the ball 11b on the side edge of the BGA package 11 to be observed via the prism 101. Each of the light sources 14f is disposed so as to be inclined inward so that the optical axis thereof intersects with the optical axis of the imaging unit 14 at the side edge of the BGA package 11. Thereby, the side edge area | region of the BGA package 11 which the image pick-up element 14a of the image pick-up part 14 is going to image is illuminated by the light source 14f.

The imaging unit 14 moves the upper surfaces 101B of the four prisms 101 arranged to face the four side edges of the BGA package 11 in the A direction (FIG. 3B) as the stage 12 moves in the XY direction. ))). Thereby, for example, as shown in the operation principle diagram in which the relay prism of FIG. 4 is omitted, the imaging element 14a of the imaging unit 14 is mounted on the side edge of the BGA package 11 via the optical system 14b and the prism 101, that is, Each mounting portion can be imaged over the entire width of one side edge of the BGA package 11 by scanning in the longitudinal direction (A direction).

By the way, the relay prism 14d of the image pickup unit 14 is supported so as to be swingable around a swing shaft 14g (see FIG. 5) extending in the A direction, that is, in the B direction (see FIG. 3 (A)). It functions as a reflective member. The relay prism 14d is swung by a swing mechanism 16 as an angle adjusting mechanism described below.

As shown in FIG. 5, the swing mechanism 16 includes a lever 17 attached to the swing shaft 14 g, a tension spring 18, and a push screw 19.
The lever 17 is configured in an L shape from a first arm 17a extending upward from the swing shaft 14g and a second arm 17b extending from the swing shaft 14g to one side in the horizontal direction (rightward in FIG. 5). Has been.

The tension spring 18 has one end 18a fixed to the inner wall of the housing 25 and the other end 18b locked to the tip of the second arm 17b so as to pull the tip of the second arm 17b upward. .
The push screw 19 is screwed into the housing 25 of the imaging unit 14, and by screwing, the tip of the push screw 19 protrudes from the inner wall of the housing 25 to resist the tension of the tension spring 18. One arm 17a is rotated around the swing shaft 14g in the direction of arrow C in FIG. On the other hand, when the push screw 19 is loosened, the upper end of the first arm 17 a follows the tip of the push screw 19 by the tension of the tension spring 18.

The scope 10 according to the first embodiment of the present invention is configured as described above, and when checking the mounting state of the BGA package 11 mounted on the substrate 11a, the following operation is performed.
First, the substrate 11 a is set on the stage 12. By appropriately moving the stage 12 in the XY direction, the imaging unit 14 is arranged to face each side edge of the BGA package 11 supported on the stage 12, that is, the upper surface of each prism 101. Scan along 101B. At this time, the light source 14f emits light, so that the light from the light source 14f enters the prism 101 from the upper surface 101B, is reflected by the reflecting surface 101A, and is irradiated on the mounting portion on the side edge of the BGA package 11. Thereby, the area | region which should be imaged with the imaging part 14 among the balls 11b of the mounting part of the side edge of the BGA package 11 is illuminated.

The light reflected by the ball 11b on the mounting portion on the side edge of the BGA package 11 by this illumination light is incident on the prism 101 again, reflected by the reflecting surface 101A, traveled upward, and emitted from the upper surface 101B. An image is formed on the imaging surface of the imaging device 14a via the relay prisms 14d and 14e and the lens 14c. The image sensor 14 a captures an image formed on the imaging surface, generates an image signal, and sends the image signal to the display unit 15. As a result, the ball 11b of the mounting portion on the side edge of the BGA package 11 is enlarged and displayed on the screen of the display unit 15. Therefore, the user can easily confirm the mounting state.

As described above, the imaging unit 14 moves in the longitudinal direction along the prism device 100, that is, the upper surface 101 B of each prism 101, so that the mounting portions on all side edges of the BGA package 11 can be confirmed.
Here, in the conventional scope, in order to thoroughly inspect a plurality of balls of the full width at one side edge of the BGA package 11, it is necessary to change the position of the scope many times. According to the form, if the prism device 100 surrounds all the side edges of the BGA package 11 and the imaging unit 14 moves along the upper surface 101B of the prism device 100, the prism device 100 is provided along all the side edges of the BGA package 11. Since the enlarged images of all the balls can be obtained, the conventional troublesome work can be eliminated.
Further, since the prism device 100 is fixedly arranged with respect to the BGA package 11 during scanning, the prism device 100 does not accidentally hit the BGA package 11 to be damaged or broken.

Here, when the user wants to observe the vicinity of the upper end or the lower end of the ball 11b mounted on the side edge of the BGA package 11 displayed on the screen of the display unit 15, the user presses the swing mechanism 16. By tightening or loosening the moving screw 19, the relay prism 14d swings around the swing shaft 14g. As a result, as shown in FIG. 3A, the optical axis of the imaging unit 14 is swung from the relay prism 14d on the BGA package 11 side, and the ball 11b on the mounting portion at the side edge of the BGA package 11 is. Is aligned vertically near the upper end or the lower end of the ball 11b. Therefore, an image near the upper end or near the lower end of the ball 11b can be formed on the image pickup surface of the image pickup device 14a in a good state and reliably observed.

In the above-described scope 10 for confirming the mounting part of the electronic component, the prism device 100 has the side surface 101C opposite to the BGA package 11 formed vertically, but is indicated by a chain line in FIG. Thus, it may be formed to be inclined so as to become thicker upward. In this case, when the optical axis is swung by the swing of the relay prism 14d, more light flux around the optical axis emitted from the prism device 100 is guided to the relay prism 14d, so that a brighter and easier-to-view image can be obtained. Become.

[Second Embodiment]
FIG. 6 shows a main part of a scope 20 for checking a mounting portion of an electronic component according to the second embodiment of the present invention. The scope 20 has the same configuration as that of the scope 10 according to the first embodiment shown in FIG. 1, and instead of the prism device 100 and the relay prisms 14 d and 14 e, the side view mirror 21, the angle adjustment mirror 22, and the fixed mirror 23. The configuration differs only in that In this case, the side viewing mirror 21 is selected such that the inclination angle θ with respect to the side edge of the BGA package 11 is greater than 45 degrees (45 degrees + α).

According to the scope 20 having this configuration, the light from the lower side of the ball 11b which is the mounting portion of the substrate 11a of the BGA package 11 is more favorably transmitted through the side view mirror 21, the angle adjustment mirror 22, and the fixed mirror 23. Guided to the imaging unit 14. Therefore, the lower side of the ball 11b is imaged well, and the mounting state can be confirmed more reliably.

[Third Embodiment]
FIG. 7 shows a main part of a scope 30 for checking a mounting portion of an electronic component according to the third embodiment of the present invention. Compared with the scope 10 according to the first embodiment shown in FIG. 1, the scope 30 is provided with a wedge prism 31 on the BGA package 11 side at the lower end of the prism device 100 while omitting the swing mechanism 16. Only the configuration is different.

The wedge prism 31 is provided on the lower side from the height of almost half of the ball 11b on the side edge of the BGA package 11, and is formed so as to gradually increase in thickness downward.

According to the scope 30 having this configuration, the inclination angle of the total reflection surface 101A of the prism device 100 is set so that the optical axis reflected by the total reflection surface 101A is on the upper side of the ball 11b, which is the mounting portion of the side edge of the BGA package 11. By selecting so as to swing, the upper side of the ball 11b is well guided to the imaging unit 14, and the light transmitted through the lower wedge prism 31 is refracted by the angle Δθ, so that the ball 11b The lower side is satisfactorily guided to the imaging unit 14 via the wedge prism 31. Therefore, the upper side and the lower side of the ball 11b are well imaged by the imaging unit 14.

[Fourth Embodiment]
FIG. 8 shows a main part of a scope 40 for checking a mounting portion of an electronic component according to the fourth embodiment of the present invention. Compared with the scope 10 according to the first embodiment shown in FIG. 1, the scope 40 has the swing mechanism 16 omitted, and the total reflection surface 101A of the prism device 100 faces the BGA package 11 side and the upper surface 101B. The configuration differs only in that the reflective surface 43A is formed in a convex shape (as viewed from the inside).

In this case, the total reflection surface 43A has the same shape in the A direction (direction perpendicular to the paper surface in FIG. 8), and forms a convex cylindrical surface as a whole.

According to the scope 40 having this configuration, the reflected light from the total reflection surface 43A of the prism device 100 is diffused based on the convex shape, so that the ball 11b, which is the mounting portion on the side edge of the BGA package 11, is viewed from above. Light from a wide angle range up to the lower side is reflected by the total reflection surface 43 A and is well guided to the imaging unit 14. Therefore, the upper side and the lower side of the ball 11b are well imaged by the imaging unit 14.

Hereinafter, other forms of the prism device will be described.
[Fifth Embodiment]
FIG. 9 is a perspective view showing a mounting portion checking prism device 100A according to a fifth embodiment of the present invention. This prism device 100A is a device for observing a mounting state of a BGA package as an electronic component mounted on a substrate, specifically, ball-shaped solder formed between the substrate and the BGA package. The prism device 100A includes a pair of

prisms

110A and 110B and a holder 120 that holds the prisms at a predetermined interval.

FIG. 10 is a

diagram showing prisms

110A and 110B according to the fifth embodiment, in which (A) is a plan view, (B) is a side view, and (C) is a front view. As shown in these drawings, the prisms 110 A and 110 B have a rectangular bottom surface 111, a side surface 112 standing up from each side of the bottom surface 111, and a horizontal top surface 113 defined by the upper edge of each side surface 112. And it is composed as a hexahedron. These

prisms

110A and 110B are made of a transparent material such as quartz, transparent resin, or glass.

Here, as shown in FIG. 10B, the bottom surfaces 111 of the

prisms

110A and 110B are formed to be inclined. Further, as shown in FIG. 11, the bottom surface 11 is formed when one side of the BGA package 11 formed in a rectangular shape, specifically, when the outline of the BGA package 11 is defined by the long side L1 and the short side L2. Is formed in a long rectangular shape along the long side L1. Unlike the prism of the first embodiment, the

prisms

110A and 110B of this embodiment do not have a length over the entire width of one side edge of the electronic component, and are set to about 10 mm to 20 mm, for example. In addition, you may provide the length over the full width of the one side edge of an electronic component. As described above, since the bottom surface 111 is formed in a long rectangular shape along the long side L1 of the BGA package 11, the

prisms

110A and 110B have a flat plate shape as a whole, and the lower portion forming the tip is formed at an acute angle. Yes.

The pair of

prisms

110A and 110B configured in this way is supported by the holder 120 so that the lower portion of the acute angle faces downward, the horizontal upper surface faces upward, and the distance between the prisms is constant.

The holder 120 includes a pair of fixing

parts

121A and 121B attached to the

prisms

110A and 110B, and connecting

parts

122A and 122B that connect the fixing

parts

121A and 121B.
As shown in FIG. 9, the fixing portions 121 A and 121 B are formed in a rectangular parallelepiped shape along the long side 111 A of the prism bottom surface, and have prism insertion holes 123 that penetrate vertically. The prism insertion hole 123 is formed so that the upper portions of the

prisms

110A and 110B are inserted.
The

prisms

110A and 110B are aligned so that the upper surfaces 113 of the

prisms

110A and 110B are flush with the upper surfaces 124 of the fixing

portions

121A and 121B in a state where they are attached to the prism insertion holes 123 of the fixing

portions

121A and 121B. It is desirable to leave.

The fixing

portions

121A and 121B to which the

prisms

110A and 110B are attached are connected to each other by a first connecting portion 122A in which one end portion of one fixing portion 121A and one end portion of the other fixing portion 121B are configured as a bar. Similarly, the other end portion of one fixing portion 121A and the other end portion of the other fixing portion 121B are connected by a second connecting portion 122B configured similarly as a bar. In this way, the holder 120 is configured to have a rectangular shape as a whole.

In the holder 120 configured as described above, the

prisms

110A and 110B are attached to the fixing

portions

121A and 121B so that the widest side surfaces are opposed to each other and the bottom surface 111 is lowered toward the opposed prism side. In the following description, the set of the left prism 110A and the fixing portion 121A that supports it in FIG. 9 is referred to as a first prism unit U1, and the set of the right prism 110B and the fixing portion 121B that supports it is a second prism. This is referred to as unit U2.

Furthermore, the prism device 100A according to the present embodiment includes the first illumination unit 130 above the upper surface of the prism of the second prism unit U2. The first illumination unit 130 is disposed so as to face the upper surface 113 of the prism 110 B, and light from the first illumination unit 130 propagates through the prism 110 B toward the bottom surface 111 through the upper surface 113.

In addition, a pair of second illumination units 131 is provided beside the upper surface of the prism of the first prism unit U1 so as not to cover the upper surface 113 of the prism 110A. The second illumination unit 131 faces the upper surface 113 of the prism 110A, and light from the second illumination unit 131 propagates through the prism 110A toward the bottom surface 111 via the upper surface 113.
As these 1st illumination part 130 and the 2nd illumination part 131, LED and a light bulb can be used.

The prism device 100A according to the fifth embodiment is configured as described above, and when used, as shown in FIG. 12, the BGA package 11 is positioned between the tip portions of the pair of

prisms

110A and 110B. In this state, the light emitted from the first illumination unit 130 of the second prism unit U2 propagates through the prism 110B of the second prism unit U2, is reflected by the inclined bottom surface 111 of the prism 110B, and becomes BGA. Irradiation is performed toward a ball 11b formed between the package 11 and the substrate 11a.

The light passes between the balls 11b or is reflected and travels, enters the acute tip portion of the first prism unit U1 on the opposite side, and enters the inclined bottom surface 111 of the prism 110A of the first prism unit U1. The light is reflected and propagates toward the upper surface 113 through the prism 110A. The light emitted from the upper surface 113 to the outside of the prism enters the imaging unit 14, an observation unit 140 such as a loupe or a microscope. The light from the second prism unit U2 functions as a backlight.

In this way, the user can mount the side edge of the BGA package 11 as shown in FIG. 13, for example, by the imaging unit 14 or the observation unit 140 such as a magnifying glass or a microscope disposed above the first prism unit U1. Part of the ball 11b can be confirmed.

By moving the observation unit 140 such as a loupe or a microscope in the longitudinal direction along the prism 110A, that is, the upper surface 113 of the prism 110A, the mounting portion on the side edge of the BGA package 11 can be confirmed. For example, the imaging unit such as a CCD is moved along the side edge of the BGA package 11 above the prism, so that the imaging unit is provided along the side edge of the BGA package 11 with respect to the substrate. All balls can be scanned accurately.

Here, in the conventional scope, in order to thoroughly inspect a plurality of balls of the full width at one side edge of the BGA package 11, it is necessary to change the position of the scope many times. According to the embodiment, if the prism device 100A is disposed to face the entire width of one side edge of the BGA package 11, and the observation unit 140 such as a loupe or a microscope moves along the upper surface 113 of the prism device 100A, the BGA package 11 is provided. Since it is possible to obtain enlarged images of all the balls 11b provided along the side edges, the conventional troublesome work can be eliminated.

Since the

prisms

110A and 110B are fixedly arranged with respect to the BGA package 11, there is no possibility that the

prisms

110A and 110B hit the BGA package 11 accidentally during scanning and are damaged or destroyed.

[Sixth Embodiment]
FIG. 14 is a perspective view showing a prism device 100B according to the sixth embodiment of the present invention. Unlike the prism device 100A according to the fifth embodiment, this prism device 100B is second with respect to the first prism unit U1. The position of the prism unit U2 can be changed, that is, the interval D between the

prisms

110A and 110B can be adjusted.

For this reason, the prism device 100B according to the sixth embodiment includes the adjustment unit 150. The adjustment unit 150 includes

connection portions

122A and 122B as the pair of bars and a lock screw 151. One end of each of the rod-shaped connecting

portions

122A and 122B is fixed to both ends of the fixing portion 121A of the first prism unit U1, and a portion other than the one end is formed on the fixing portion 121B of the second prism unit U2. Is inserted into the through-hole 125. The fixing portion 121B of the second prism unit U2 is slidable with respect to the connecting

portions

122A and 122B, and the movement of the fixing portion 121B along the longitudinal direction of the connecting

portions

122A and 122B is restricted. A lock screw 151 is provided at the end of the fixed portion 121B of the second prism unit U2. By tightening the lock screw 151, the tip of the lock screw 151 hits the connecting portion 122A, and the fixing portion 121B is locked at a fixed position.

According to the prism device 100B provided with the adjusting unit 150, the interval between the

prisms

110A and 110B can be adjusted, so that the mounting state of the BGA package 11 having different dimensions can be confirmed with one prism device 100B. .

[Modification of Sixth Embodiment]
FIG. 15 is a perspective view showing a prism device 100C according to a modification of the sixth embodiment of the present invention. This prism device 100C is different in the configuration of the adjustment unit 150 from the prism device 100B according to the sixth embodiment. Specifically, the adjustment unit 150A of the present embodiment is configured in a pantograph manner.

For this reason, in the prism device 100C of the present embodiment, the adjustment unit 150A is a pair of arms in which the base end portion is rotatably attached to each of the fixing

portions

121A and 121B and the distal end portion is slidably connected to the other fixing portions. 153A and 153B are provided. Specifically,

rail members

155A and 155B are attached to the inner surfaces of the fixed

portions

121A and 121B. A base end portion of one arm 153A is rotatably attached to an end portion of the rail member 155A, and a distal end portion of the other arm 153B is slidably attached to the rail member 155A. Similarly, the base end portion of one arm 153B is rotatably attached to the end portion of another rail member 155B, and the tip end portion of the other arm 153A slides on the rail member 155B. It is attached movably. As shown in FIG. 15, a lock pin 154 is attached to the tip of one arm 153A, and the movement of the arm tip is regulated by tightening the lock pin 154. These

arms

153A and 153B are connected to each other via a rotation shaft 156 at an intermediate portion in the longitudinal direction.

According to the prism device 100C including the pantograph type adjustment unit 150A, the distance D between the

prisms

110A and 110B can be adjusted by expanding and contracting the pair of

arms

153A and 153B in a pantograph type. The mounting state of the BGA package 11 having different dimensions can be confirmed by the prism device 100C.

[Seventh Embodiment]
FIG. 16 is a diagram showing an image processing system 200 according to the seventh embodiment of the present invention. This image processing system 200 includes the prism device 100A (or 100B to 100C) as the side-viewing optical member, and one of them. An imaging unit 210 provided on the upper side of the prism 110 A, and a processing unit 220 configured as a computer that processes an image captured by the imaging unit 210.
As shown in the figure, the electronic component 11 mounted on the substrate 11a is disposed between the bottom surfaces of the pair of

prisms

110A and 110B. In this state, when the light source 230 disposed on the upper side of the other prism 110B is caused to emit light, the light is reflected by the bottom surface of the prism 110B, and further passes through the gap in the mounting portion of the electronic component 11 to the other prism 110A. Is incident on. As a result, the imaging unit 210 captures an image of the mounting portion of the electronic component 11 in a state of being back illuminated by the light source 230, as shown in FIG. That is, the image of the mounting part imaged by the imaging unit 210 is obtained as a black and white image by the back illumination by the light source 230, and the gap between the balls 11b is white, and the balls 11b and foreign matter are imaged black.

Based on the image thus created, the processing unit 220 performs image processing to measure and detect the ball height H, the ball interval W, and the BGA internal foreign matter X as shown in FIG. Specifically, as shown in FIG. 19A, the processing unit 220 includes a template that shows a black and white silhouette image between good balls, and the acquired image as shown in FIG. It is determined how many parts match the silhouette image. As a result, when the detected number is equal to or less than the set value, it is determined that there is a defect such as a foreign object defect.
For the ball height H and the ball interval W, an area that matches the silhouette image is extracted. If the height is based on the center of the area, the average height in the range of ± Δ in the horizontal direction is obtained. If it is an interval, an average of intervals in a range of ± H is obtained in the vertical direction. The processing unit 220 determines that the ball 11b is defective or the like when the height or interval of the balls 11b is equal to or less than a set value.
As described above, according to the image processing system 200 according to the present embodiment, by using the prism device 100A (or 100B to 100C) as the side-viewing optical member, the mounting portion of the BGA package to be observed, that is, the solder Since the ball 11b is back illuminated by the light source 230 and can be imaged, a substantially binarized image can be obtained. Thereby, an image with a clear ball shape can be acquired. Therefore, it is possible to easily determine whether the mounting state is good or bad. Specifically, it is possible to accurately measure the ball interval and the ball height.

Although detailed above, the present invention can be implemented in various forms without departing from the spirit of the present invention.
For example, in the above-described embodiment, the prism device 100 is disposed so as to face all the side edges of the BGA package 11. However, the present invention is not limited to this. For example, two side edges or only one edge of the BGA package 11 is provided. The prism device 100 may be composed of two or one prisms 101 so as to have two or one reflecting surfaces 11B so as to face the side edges.

Further, in the scope 20 according to the embodiment shown in FIG. 6, the side-viewing mirror 21 as the side-viewing optical member has an inclination angle larger than 45 degrees with respect to the side edge of the BGA package 11. In addition to this, also in other embodiments, the reflective surface 101A of the prism device 100 may similarly have an inclination angle greater than 45 degrees with respect to the side edge of the BGA package 11.
In the above configuration example, the scope is configured to swing the relay prism 14e, which is a reflection member in the housing 25, but the housing 25 itself on the imaging unit 14a side, more specifically, the housing 25, The scope main body 26 itself formed by combining the lens 14c and the imaging unit 14a may be configured to swing. In this case, for example, a shaft for swingably supporting the scope main body 26 is provided on the bracket 12F protruding upward from the upper end of the support column 12E provided attached to the stage 12 shown in FIG.
In the above description, the prism device is moved in the XY direction on the stage 12 so that the imaging unit 14a moves relatively on the prism device. However, without using this type of stage, for example, The imaging unit 14a and the scope main body 26 may be supported by a robot arm and moved on the prism device.

Further, in the above-described embodiment, the ball 11b as the mounting portion of the side edge of the BGA package 11 is observed as an electronic component. However, the present invention is not limited to this, and mounting of the side edge of another electronic component is performed. Obviously, the part may be observed.

In addition, the prism device of the present invention may be configured by omitting the first illumination unit 130 and / or the second illumination unit 131.

Furthermore, in the above-described embodiment, it is configured to observe the ball as the mounting portion on the side edge of the BGA package as the electronic component, but not limited to this, the mounting portion on the side edge of another electronic component is used. Obviously it may be observed.
In the description of the above embodiment, the pair of

prisms

110A and 110B are formed in a flat plate shape, the surface facing the other prism and the back surface thereof are formed in parallel, and the surface facing the prism and the bottom surface 111 have sharp edges. However, the pair of prisms of the present invention may be configured as follows, for example. FIG. 20A is a front view showing a prism 110C according to another embodiment of the present invention, and FIG. 20B is a side view. As shown in these figures, the prism 110C includes a bottom surface 111 that is inclined in the same manner as the

prisms

110A and 110B described above, but is further inclined downward from the surface P1 facing the other prism toward the back surface P2. The lower surface of the inclined surface 115 and the lower surface of the bottom surface 111 are joined together to form an edge E. In such a prism 110 C, the upper surface 113 is formed wider than the bottom surface 111 in the horizontal direction. By forming the upper portion of the prism wider than the bottom surface 111 in this way, it is possible to make it easy to visually recognize an image reflected from the bottom surface 111 of the prism from above the prism.

Claims

A side-viewing optical member having a reflective surface facing the side edge over the entire width of one side edge of the electronic component mounted on the substrate.
The optical member for side view according to claim 1, comprising the reflecting surface facing two side edges of the electronic component.
The side-viewing optical member according to claim 2, wherein the optical member has the reflecting surface facing each side edge of each side of the electronic component.
A reflection member for angle adjustment supported so as to be able to swing around a swinging shaft, and an angle adjusting mechanism for swinging the reflecting member around the swinging shaft, and swinging the reflecting member. The side-viewing optical member according to any one of claims 1 to 3, wherein an imaging region of the mounting portion can be changed.
The side-viewing optical member according to claim 4, comprising a prism having a total reflection surface facing a side edge of the electronic component.
The side-viewing optical member according to claim 4, further comprising a mirror having a total reflection surface facing a side edge of the electronic component.
A pair of prisms;
A holder for holding the prisms at a predetermined interval,
The prism has an inclined bottom surface and a horizontal top surface,
The bottom is down towards the opposite prism side,
A side-viewing optical member in which light incident from one upper surface of the pair of prisms is reflected to the other prism side at the bottom surface of the prism.
The side-viewing optical member according to claim 7, wherein the holder includes a fixing portion attached to each of the pair of prisms, and an adjustment portion that adjusts an interval between the fixing portions.
The adjustment portion includes a bar fixed to one fixing portion and slidably connected to the other fixing portion,
The side-viewing optical member according to claim 8, wherein the distance between the prisms changes as the other fixing portion moves while being guided by the bar.
The adjustment portion includes a pair of arms having a base end portion rotatably attached to each fixing portion and a distal end portion slidably connected to other fixing portions,
The arms are connected to each other via a rotating shaft at the middle in the longitudinal direction,
The side-viewing optical member according to claim 8, wherein a distance between the pair of prisms is changed by expanding and contracting the pair of arms in a pantograph manner.
At least one light source is provided above one prism,
The side-viewing optical member according to any one of claims 7 to 10, wherein light from the light source is incident from the upper surface of the prism, reflected by the bottom surface of the prism, and emitted toward the other prism.
The optical member for side view according to claim 11,
An imaging unit provided above the other prism;
A processing unit that processes an image captured by the imaging unit,
An electronic component mounted on a substrate is disposed between the bottom surfaces of the pair of prisms, light from a light source provided on the upper side of the one prism is reflected by the bottom surface of the one prism, By passing through the gap and entering the other prism, the imaging unit images the mounting part of the electronic component while being back illuminated by the light source,
An image processing system in which the processing unit processes an image of the mounting part.
The image according to claim 12, wherein an image of the mounting part imaged by the imaging unit is obtained as a black and white image by back illumination by the light source, and the gap between the balls is white and the ball and the foreign object are imaged black. Processing system.