JP3047557B2 - Method of correcting image brightness of camera in appearance inspection of soldering state of electronic component - Google Patents
Method of correcting image brightness of camera in appearance inspection of soldering state of electronic componentInfo
- Publication number
- JP3047557B2 JP3047557B2 JP3264482A JP26448291A JP3047557B2 JP 3047557 B2 JP3047557 B2 JP 3047557B2 JP 3264482 A JP3264482 A JP 3264482A JP 26448291 A JP26448291 A JP 26448291A JP 3047557 B2 JP3047557 B2 JP 3047557B2
- Authority
- JP
- Japan
- Prior art keywords
- luminance
- camera
- inspection
- appearance inspection
- electronic component
- 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.)
- Expired - Fee Related
Links
Landscapes
- Electric Connection Of Electric Components To Printed Circuits (AREA)
- Image Analysis (AREA)
- Image Input (AREA)
- Image Processing (AREA)
- Closed-Circuit Television Systems (AREA)
Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【0001】[0001]
【産業上の利用分野】本発明は電子部品の半田付状態の
外観検査におけるカメラの画像輝度の補正方法に係り、
詳しくは、外観検査装置同士の画像輝度のばらつきを補
正して、良否判断のばらつきを解消するための手段に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting image brightness of a camera in an appearance inspection of a soldered state of an electronic component.
More specifically, the present invention relates to means for correcting variations in image luminance between appearance inspection devices and eliminating variations in quality judgment.
【0002】[0002]
【従来の技術】基板に実装された電子部品の半田付状態
の外観検査手段として、カメラにより半田を観察し、そ
の輝度分布状態から半田付状態の良否を判断する方法が
知られている。このような外観検査は、一般に、検査対
象物である半田を取り囲む検査エリアを設定し、この検
査エリア内において、設定輝度以上、あるいは所定輝度
以下の画素数を求めることにより行われる。2. Description of the Related Art As a means for inspecting the appearance of soldering of an electronic component mounted on a board, there is known a method of observing solder with a camera and judging the quality of the soldering from the brightness distribution. Such an appearance inspection is generally performed by setting an inspection area surrounding the solder as an inspection object, and calculating the number of pixels having a luminance equal to or higher than a set luminance or equal to or lower than a predetermined luminance in the inspection area.
【0003】ところがこのような良否判断は、外観検査
装置毎にばらつきやすいものである。すなわち、図5
(a)(b)は、2台の外観検査装置(A装置とB装
置)で同一の半田を観察した場合の各々のカメラに取り
込まれた画像の輝度分布を示している。横軸は輝度、縦
軸は画素数、PAは良否判断のための設定輝度である。
本例では、A装置の画面は明るく、またB装置の画面は
暗い。[0003] However, such a good / bad judgment is likely to vary from one appearance inspection apparatus to another. That is, FIG.
(A) and (b) show the luminance distribution of images captured by each camera when the same solder is observed by two appearance inspection devices (A device and B device). The horizontal axis is the luminance, the vertical axis is the number of pixels, and PA is the set luminance for judging pass / fail.
In this example, the screen of the device A is bright and the screen of the device B is dark.
【0004】良否判断は、設定輝度PA以上の画素数す
なわち図中、影線部の面積thA,thBが、設定面積
TH以上であるか否かによりなされる。ところが図示す
るように、A装置とB装置の輝度分布はかなり相違して
おり、このため同一半田を観察した場合、A装置では半
田形状は良と判断し、B装置では不良と判断し、判断結
果がばらついてしまう。[0004] The pass / fail judgment is made based on whether or not the number of pixels having a luminance equal to or higher than the set luminance PA, that is, whether the areas thA and thB of the shadow line portions in the drawing are equal to or larger than the predetermined area TH. However, as shown in the figure, the luminance distributions of the device A and the device B are considerably different. For this reason, when the same solder is observed, the device A determines that the solder shape is good, and the device B determines that the solder shape is defective. The results vary.
【0005】このような輝度分布のばらつきは、主とし
て、照明系の照度のばらつきや、カメラの感度調整のば
らつきに起因する。[0005] Such variations in luminance distribution are mainly caused by variations in illuminance of the illumination system and variations in sensitivity adjustment of the camera.
【0006】そこで本発明は、上記のような器差に基づ
く外観検査装置毎の良否判断のばらつきを解消できる電
子部品の外観検査手段を提供することを目的とする。SUMMARY OF THE INVENTION It is an object of the present invention to provide a means for inspecting the appearance of an electronic component, which can eliminate variations in the quality judgment of each appearance inspection apparatus based on the above-mentioned instrumental differences.
【0007】[0007]
【課題を解決するための手段】このために本発明は、明
度若しくは光反射率の異なる部分を有する検査モデルを
設け、この検査モデルを複数の外観検査装置により観察
して、各々のカメラに取り込まれた画像の輝度特性を求
め、また何れかの外観検査装置をマスター装置として選
択し、このマスター装置の上記輝度特性に、他の外観検
査装置の輝度特性が合致するように、この輝度特性を補
正するようにしている。Means for Solving the Problems] The present invention To this end, light
Inspection models with different degrees of light or reflectivity
The inspection model is observed by a plurality of appearance inspection devices, the luminance characteristics of the images captured by each camera are obtained, and any one of the appearance inspection devices is selected as a master device, and the luminance of the master device is determined. This luminance characteristic is corrected so that the characteristic matches the luminance characteristic of another appearance inspection device.
【0008】[0008]
【作用】上記構成によれば、外観検査装置同士の画像の
輝度特性のばらつきは補正され、良否判断のばらつきは
解消される。According to the above arrangement, variations in the luminance characteristics of the images between the visual inspection devices are corrected, and variations in the quality judgment are eliminated.
【0009】[0009]
【実施例】次に、図面を参照しながら本発明の実施例を
説明する。Next, an embodiment of the present invention will be described with reference to the drawings.
【0010】図1は外観検査装置の全体図であって、1
はXYテーブルであり、カメラ2とリング状の光源3が
装着されている。4は基板であり、電子部品5が半田6
により固着されている。7は基板搬送用コンベヤであ
る。Eは検査対象物の半田6を取り囲むように設定され
たカメラ2の検査エリアである。8は基板4の側方に設
けられたテーブルであって、検査モデルMが載置されて
いる。この検査モデルMは、明度若しくは光反射率の異
なる部分として、白部WHと黒部BLを有している。FIG. 1 is an overall view of an appearance inspection apparatus.
Denotes an XY table on which a camera 2 and a ring-shaped light source 3 are mounted. Reference numeral 4 denotes a substrate, on which electronic components 5 are solder 6
Is fixed. Reference numeral 7 denotes a substrate transport conveyor. E denotes an inspection area of the camera 2 set to surround the solder 6 to be inspected. Reference numeral 8 denotes a table provided on the side of the substrate 4, on which an inspection model M is placed. The inspection model M has a white portion WH and a black portion BL as portions having different lightness or light reflectance.
【0011】図2は、図1に示す同一構造の2台の外観
検査装置(A装置及びB装置)で、上記検査モデルMを
観察した場合の各々のカメラ2に取り込まれた画像の輝
度分布を示している。図中、実線はA装置、鎖線はB装
置の画像の輝度分布であり、図示するように、白部WH
と黒部BLの各々のピーク輝度Pa1とPb1,及びP
a2とPb2は、光源3の照度やカメラ2の感度調整の
ばらつきによりずれが生じている。本実施例では、A装
置の画面は、B装置の画面よりも明るく、したがってB
装置の輝度分布は、A装置の輝度分布よりも、輝度が低
い方にずれている。FIG. 2 shows the luminance distribution of an image captured by each camera 2 when the inspection model M is observed by two appearance inspection apparatuses (A apparatus and B apparatus) having the same structure shown in FIG. Is shown. In the figure, the solid line is the luminance distribution of the image of the device A, and the chain line is the luminance distribution of the image of the device B. As shown in FIG.
And the black portions BL, the peak luminances Pa1, Pb1, and P
a2 and Pb2 are displaced due to variations in the illuminance of the light source 3 and the sensitivity adjustment of the camera 2. In this embodiment, the screen of the device A is brighter than the screen of the device B,
The luminance distribution of the device is shifted to a lower luminance than the luminance distribution of device A.
【0012】図3(a)(b)は、A装置とB装置で同
一半田6を観察した場合の検査エリアEの輝度分布を示
している。図5を参照しながら説明したように、良否判
断は、設定輝度PA以上の画素数、すなわち影線部の面
積thA,thBが設定面積TH以上であるか否かによ
りなされる。FIGS. 3 (a) and 3 (b) show the luminance distribution of the inspection area E when the same solder 6 is observed by the A device and the B device. As described with reference to FIG. 5, the pass / fail judgment is made based on whether or not the number of pixels equal to or higher than the set luminance PA, that is, whether or not the areas thA and thB of the shadow line portions are equal to or larger than the set area TH.
【0013】本実施例では、A装置の面積thAはTH
以上であって、半田形状は良と判断されるが、B装置の
面積thBはTH以下であって不良と判断される。ここ
で、実際の半田6は良品であって、A装置の判断が正し
いとする。そこでA装置をマスター装置として選択し、
次のような方法により、B装置のthBがA装置のth
Aと等しくなるような設定輝度の補正値PA’を求め
る。In this embodiment, the area thA of the device A is TH
As described above, the solder shape is determined to be good, but the area thB of the B device is equal to or less than TH and is determined to be defective. Here, it is assumed that the actual solder 6 is a non-defective product and the judgment of the device A is correct. So we select the device A as the master device,
By the following method, the thB of the B apparatus is changed to the thB of the A apparatus.
A correction value PA ′ of the set luminance that is equal to A is obtained.
【0014】図4は、図2に基づくA装置とB装置の輝
度特性を示すものであって、横軸は検査モデルMの明
度、若しくは光反射率、縦軸は設定輝度、AはA装置の
輝度特性、BはB装置の輝度特性である。A装置とB装
置の輝度特性は、それぞれ次のとおりである。FIG. 4 shows the luminance characteristics of the A apparatus and the B apparatus based on FIG. 2, wherein the horizontal axis represents the brightness or light reflectance of the inspection model M, the vertical axis represents the set luminance, and A represents the A apparatus. And B is the luminance characteristic of the B apparatus. The luminance characteristics of the device A and the device B are as follows.
【0015】 yA=ax+b・・・(1) yB=cx+d・・・(2) 式(1)からx=(yA−b)÷aであり、これを式
(2)に代入すると、 yB=c(yA−b)÷a+d・・・(3) となる。YA = ax + b (1) yB = cx + d (2) From Expression (1), x = (yA−b) ÷ a, and when this is substituted into Expression (2), yB = c (yA−b) ÷ a + d (3)
【0016】すなわち、A装置とB装置の輝度特性は式
(3)で示される関係にある。そこでyAにPAを代入
することにより、補正されたPA’を求めることができ
る。That is, the luminance characteristics of the device A and the device B are in a relationship represented by the equation (3). Therefore, the corrected PA ′ can be obtained by substituting PA for yA.
【0017】 PA’=c(PA−b)÷a+d・・・(4) そこで、B装置の設定輝度をPAからPA’に補正すれ
ば、B装置の輝度特性は、A装置の輝度特性と合致する
よう補正されたこととなり、thBはthAと同じにな
って、A装置とB装置で同じ半田6を観察すると、同一
良否判断がなされることとなる。PA ′ = c (PA−b) ÷ a + d (4) Therefore, if the set luminance of the B apparatus is corrected from PA to PA ′, the luminance characteristic of the B apparatus becomes the same as the luminance characteristic of the A apparatus. The correction has been made so that they match, and thB becomes the same as thA. When the same solder 6 is observed in the A device and the B device, the same pass / fail judgment is made.
【0018】上記実施例では、B装置のthBがA装置
thAに等しくなるPA’を求めたが、B装置の設定輝
度PAを一定にして、B装置のthBがA装置のthA
に等しくなるthB’を求めるよう補正を行ってもよ
い。In the above-described embodiment, PA 'is obtained such that the thB of the B apparatus is equal to the thA of the A apparatus. However, the set brightness PA of the B apparatus is kept constant, and the thB of the B apparatus becomes the thA of the A apparatus.
May be corrected so as to obtain thB ′ that is equal to
【0019】[0019]
【発明の効果】以上説明したように本発明は、明度若し
くは光反射率の異なる部分を有する検査モデルを設け、
この検査モデルを複数の外観検査装置により観察して、
各々のカメラに取り込まれた画像の輝度特性を求め、ま
た何れかの外観検査装置をマスター装置として選択し、
このマスター装置の上記輝度特性に、他の外観検査装置
の輝度特性が合致するように、この輝度特性を補正する
ようにしているので、電子部品の半田付状態の外観検査
において、外観検査装置同士の画像輝度特性のばらつき
を補正し、半田付状態の良否判断のばらつきを解消でき
る。As described above, the present invention has a low brightness.
Or an inspection model having different parts of light reflectance,
Observing this inspection model with a plurality of visual inspection devices,
Obtain the luminance characteristics of the image captured by each camera, and select one of the visual inspection devices as the master device,
To the luminance characteristics of the master device, so that the brightness characteristics of the other inspection systems are met, since so as to correct the luminance characteristic, visual inspection of the soldering state of the electronic component
In this case, it is possible to correct the variation in the image luminance characteristics between the visual inspection devices, and eliminate the variation in the determination of the good or bad of the soldering state .
【図1】本発明に係る外観検査装置の斜視図FIG. 1 is a perspective view of a visual inspection device according to the present invention.
【図2】本発明に係る検査モデルの輝度分布図FIG. 2 is a luminance distribution diagram of an inspection model according to the present invention.
【図3】本発明に係る画像の輝度分布図FIG. 3 is a luminance distribution diagram of an image according to the present invention.
【図4】本発明に係る画像の輝度特性図FIG. 4 is a luminance characteristic diagram of an image according to the present invention.
【図5】従来の画像の輝度分布図FIG. 5 is a luminance distribution diagram of a conventional image.
2 カメラ M 検査モデル 2 Camera M inspection model
Claims (2)
る検査モデルを設け、この検査モデルを複数の外観検査
装置により観察して、各々のカメラに取り込まれた画像
の輝度特性を求め、また何れかの外観検査装置をマスタ
ー装置として選択し、このマスター装置の上記輝度特性
に、他の外観検査装置の輝度特性が合致するように、こ
の輝度特性を補正することを特徴とする電子部品の半田
付状態の外観検査におけるカメラの画像輝度の補正方
法。(1) having portions having different lightness or light reflectance
An inspection model is provided, the inspection model is observed by a plurality of appearance inspection devices, the luminance characteristic of the image captured by each camera is obtained, and any one of the appearance inspection devices is selected as a master device. to the luminance characteristics of the device, as the luminance characteristics of the other inspection systems matches, solder electronic components and correcting the luminance characteristic
A method for correcting the image brightness of a camera in an appearance inspection in an attached state .
が、白部と黒部であることを特徴とする請求項1記載のIs a white part and a black part.
電子部品の半田付状態の外観検査におけるカメラの画像Image of camera in appearance inspection of soldering state of electronic components
輝度の補正方法。Brightness correction method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3264482A JP3047557B2 (en) | 1991-10-14 | 1991-10-14 | Method of correcting image brightness of camera in appearance inspection of soldering state of electronic component |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3264482A JP3047557B2 (en) | 1991-10-14 | 1991-10-14 | Method of correcting image brightness of camera in appearance inspection of soldering state of electronic component |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH05108801A JPH05108801A (en) | 1993-04-30 |
JP3047557B2 true JP3047557B2 (en) | 2000-05-29 |
Family
ID=17403852
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3264482A Expired - Fee Related JP3047557B2 (en) | 1991-10-14 | 1991-10-14 | Method of correcting image brightness of camera in appearance inspection of soldering state of electronic component |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3047557B2 (en) |
-
1991
- 1991-10-14 JP JP3264482A patent/JP3047557B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
JPH05108801A (en) | 1993-04-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7505149B2 (en) | Apparatus for surface inspection and method and apparatus for inspecting substrate | |
JP2006515112A (en) | Automatic optical inspection system and method | |
US7062080B2 (en) | Method of inspecting curved surface and device for inspecting printed circuit board | |
EP1314974B1 (en) | Method of inspecting curved surface and device for inspecting printed circuit board | |
JP3047557B2 (en) | Method of correcting image brightness of camera in appearance inspection of soldering state of electronic component | |
JPH11234706A (en) | Adjustment device for video image of television camera | |
JP3304152B2 (en) | Color unevenness inspection device | |
KR101136387B1 (en) | A Method For Inspecting Automobile Parts Using Vision System | |
KR19990018136A (en) | Color quality inspection method and device | |
JPH08105722A (en) | Illuminator for inspecting device external appearance and device external appearance automatic inspecting apparatus using the illuminator | |
JP2004170329A (en) | Bump electrode and ball inspection method for the same | |
JPH06174444A (en) | Soldered state inspection method for discrete type electronic component | |
JPH11224784A (en) | Illumination appliance, and its illuminance adjusting method | |
JPH0267949A (en) | Soldered part checking apparatus | |
JPH09236487A (en) | Method for inspecting cover tape of embossed tape | |
KR970012877A (en) | Cathode ray tube screen inspection adjusting device and method | |
KR0137950Y1 (en) | Apparatus for checking the mounting state of the part that is mounted on printed board | |
JPS62173076A (en) | Method for soldering by laser | |
JPH05126550A (en) | Surface state inspecting method | |
JP2001066120A (en) | Surface inspection device | |
JP3038107B2 (en) | Soldering inspection method | |
JP3832236B2 (en) | Image recognition apparatus and image recognition method | |
JP2605971B2 (en) | Observation equipment | |
JPH06160035A (en) | Substrate inspection device | |
US6638127B2 (en) | Master cathode ray tube jig with LEDs simulating stray emissions for calibration of a stray emissions detection system and methods of making and using same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080324 Year of fee payment: 8 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090324 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100324 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110324 Year of fee payment: 11 |
|
LAPS | Cancellation because of no payment of annual fees |