JPS59126233A - Apparatus for inspecting through-hole of printed circuit board - Google Patents

Apparatus for inspecting through-hole of printed circuit board

Info

Publication number
JPS59126233A
JPS59126233A JP22836982A JP22836982A JPS59126233A JP S59126233 A JPS59126233 A JP S59126233A JP 22836982 A JP22836982 A JP 22836982A JP 22836982 A JP22836982 A JP 22836982A JP S59126233 A JPS59126233 A JP S59126233A
Authority
JP
Japan
Prior art keywords
hole
light
filter
defect
detecting
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.)
Granted
Application number
JP22836982A
Other languages
Japanese (ja)
Other versions
JPH0442622B2 (en
Inventor
Giichi Kakigi
柿木　義一
Kikuo Mita
三田　喜久夫
Moritoshi Ando
護俊 安藤
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP22836982A priority Critical patent/JPS59126233A/en
Priority to US06/554,543 priority patent/US4560273A/en
Priority to EP83307291A priority patent/EP0111404B1/en
Priority to DE8383307291T priority patent/DE3377527D1/en
Publication of JPS59126233A publication Critical patent/JPS59126233A/en
Publication of JPH0442622B2 publication Critical patent/JPH0442622B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G01N21/95—Investigating the presence of flaws or contamination characterised by the material or shape of the object to be examined
    • G01N21/956—Inspecting patterns on the surface of objects
    • G01N21/95692—Patterns showing hole parts, e.g. honeycomb filtering structures

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)

Abstract

PURPOSE:To inspect the position and defect of a through-hole, by masking one end opening of the through-hole with a filter pervious to only light with a specific wavelength while detecting lights permeating and not permeating the filter in the opposite side of said through-hole. CONSTITUTION:A filter 5 for masking one end opening of a through-hole 4 of a print board 1 is arranged to one surface side of said printed circuit board in a closely contacted state. The filter 5 is pervious to light with a specific wavelength, for example, only to green light. In addition, an illumination apparatus 6 for emitting both of light permeating the filter 5 and light having a wavelength not permeating the filter, for example, red light is arranged to the arranged side of the filter 5. In the other surface side of the print board 1, a light detector 10 for detecting the presence or absence of the through-hole 4 and the position thereof through a half-mirror 8 and a filter 9 pervious only to green light is provided on the light axis of a condensing lens 7 and a light detector 12 for detecting the defect of the through-hole 4 through a filter 11 pervious only to red light is further provided on the reflected light axis due to the mirror 8. By this mechanism, positive defect detection can be carried out.

Description

【発明の詳細な説明】 （１）０発明の技術分野 本発明はプリント板のスルーホール内壁に生じたピンホ
ールなどの欠陥を光学的に検・出するためのスルーホー
ル検査装置に関するものである。Detailed Description of the Invention (1) 0 Technical Field of the Invention The present invention relates to a through-hole inspection device for optically detecting defects such as pinholes occurring on the inner wall of the through-hole of a printed circuit board. .

（２）、技術の背景 両面プリント板の表裏導体の接続、あるいは多層プリン
ト板の層間導体の接続には、スルーホールメッキ法が広
く用いられている。かかるスルーホールメッキ法は、導
体を積層した絶縁基板に予め孔あけ加工し、この透孔内
壁面に化学的あるいは電気的にメッキ層を生成すること
で導体間を電気的に接続するものであるが、該メッキ［
Ｕミクロン単位の厚さであるとともに、透孔内壁面の凹
凸が激しく、かつ小径であるため、スルーホールの生成
メッキ層にピンホール、切れ目等の欠陥が生じる場合が
往々あり、そしてメッキ層の欠陥部が太きいと、導体間
の電気的導通の不良につながシ、プリント板の信頼性の
上で大きな問題となる。従って、このようなスルーホー
ルの欠陥を容易にかつ確実に検査できることが望まれて
いる。(2) Background of the Technology Through-hole plating is widely used to connect front and back conductors of double-sided printed boards or to connect interlayer conductors of multilayer printed boards. In this through-hole plating method, holes are pre-drilled in an insulating substrate on which conductors are laminated, and a plating layer is chemically or electrically formed on the inner wall surface of the holes to electrically connect the conductors. However, the plating [
Due to the thickness of U microns, the roughness of the inner wall surface of the through hole, and the small diameter, defects such as pinholes and cuts often occur in the plating layer that forms the through hole. If the defective portion is thick, it may lead to poor electrical continuity between the conductors, which poses a major problem in terms of the reliability of the printed board. Therefore, it is desired that defects in such through holes can be easily and reliably inspected.

（３）、従来技術の問題点 従来、プリント板のスルーホール検査方式は、検査用光
源で照明される側のプリント板のスルーホール部分をマ
スクし、そして非マスク部分よりプリント板の基板材内
に入射して拡散された光がスルーホール内に漏れている
か否かを光検知器により検知することで、スルーホール
にピンホール等の欠陥を検出するようになっている。(3) Problems with the conventional technology Conventionally, in the through-hole inspection method for printed circuit boards, the through-hole portion of the printed board on the side illuminated by the inspection light source is masked, and the inside of the substrate material of the printed board is Defects such as pinholes in the through holes are detected by using a photodetector to detect whether the light that has entered and diffused leaks into the through holes.

しかし、かかる従来方式では、スルーホールの有無及び
その位置を知ることができない。このため、プリント板
の基板材部分が検査位置に割出された場合には、基板材
内部を透過した光が光検知器で感知され、その結果、あ
たかもスルーホール欠陥があるかの如く判断されること
になるほか、スルーホールの検査位置への割出位置がず
れてランド部分が光検知器に対向していた場合には、ス
ルーホールに欠陥があっても、欠陥がないと判定されて
しまうことになる。However, with this conventional method, it is not possible to know the presence or absence of a through hole and its position. Therefore, when the board material part of the printed board is indexed to the inspection position, the light that has passed through the inside of the board material is detected by the photodetector, and as a result, it is judged as if there is a through-hole defect. In addition, if the indexing position of the through-hole to the inspection position is shifted and the land part is facing the photodetector, it will be determined that there is no defect even if the through-hole is defective. It will end up being put away.

（４）１発明の目的 本発明は上記従来の問題を解決したもので、スルーホー
ルの有無、位置及び欠陥の有無を検知可能にし、併せて
スルーホール検査の確実性及び能率化を図るようにした
プリント板のスルーホール検査装置を提供することを目
的とする。(4) 1. Purpose of the Invention The present invention solves the above-mentioned conventional problems, and makes it possible to detect the presence or absence of through holes, their position, and the presence or absence of defects, and also to improve the reliability and efficiency of through hole inspection. The purpose of the present invention is to provide a through-hole inspection device for printed circuit boards.

（５）１発明の構成 上記目的全達宰するために本発明のプリント板のスルー
ホール検査装置は、プリント板に形成されたスルーホー
ルの一端開口を特定波長の光のみを透過させるフィルタ
によりマスクするとともに、このマスク面側から上記フ
ィルタを透過する光と該フィルタを透過しない光の双方
を発する照明装置に、ｌ：９照明し、かつ上記マスク面
と反対の側には、上記フィルタ全透過する光を検知して
スルーホールの位置を検知するための、及び上記フィル
タを透過しない光を検知することでスルーホールの欠陥
を検知するための光検知手段を設置したものである。(5) 1 Structure of the Invention In order to achieve all of the above objects, the printed board through-hole inspection device of the present invention masks one end opening of a through-hole formed in a printed board with a filter that transmits only light of a specific wavelength. At the same time, an illumination device that emits both the light that passes through the filter and the light that does not pass through the filter is illuminated from the side of the mask surface at 1:9, and on the side opposite to the mask surface, the light that is completely transmitted through the filter is illuminated. A light detection means is installed to detect the position of the through hole by detecting the light that passes through the filter, and to detect a defect in the through hole by detecting the light that does not pass through the filter.

（６）０発明の実施例 以下、本発明の実施例を図面によって説明する。(6) Example of 0 invention Embodiments of the present invention will be described below with reference to the drawings.

第１図は本発明にかかるプリント板のスルーホール検出
装置７ｊの一例を示すもので、１は検査されるプリント
板であり、このプリント板１を構成するノ４（板材２は
、例えばガラス繊維にエポキシｉＩ脂を含浸させた光透
過性の物質から成り、そして基板材２に穿設した透孔２
ａの内壁にメッキ層３を生成することで表裏導体（ラン
ド部）を電気的に接続するスルーホール４が形成されて
いる。FIG. 1 shows an example of a printed board through-hole detection device 7j according to the present invention, in which 1 is a printed board to be inspected, and the board 4 (board material 2 is made of, for example, glass fiber) that constitutes this printed board 1. It is made of a light-transmitting material impregnated with epoxy II resin, and has a through hole 2 formed in the substrate material 2.
By forming a plating layer 3 on the inner wall of a, a through hole 4 is formed to electrically connect the front and back conductors (land portions).

このようにしたプリント板１の一面側には、スルーホー
ル４の一端開口をマスクするフィルタ５が密接状態に配
置されてお夕、このフィルタ５は特定波長の光、例えば
緑色の光のみが透過するものである。寸た、上記フィル
タ５の配置側には、上記フィルタ５を透過する光（例え
ば緑色）と、該フィルタ５を透過しない波長の光、例え
ば赤色の光の双方を発する照明装置６が配置されている
。７は上記プリント板１の他面側において、検査される
スルーホール４に対向して配置された集光レンズで、ス
ルーホール４内全透過してくる光を集光するものであり
、このレンズ７の光軸上にはノ・−フミラー８及び緑色
の光のみを透過するフィルタ９を介してスルーホール４
の有無及び位置を検知する光検知器１０が設置され、さ
らに上記ノ・−フミラー８による反射光軸上には赤色の
光のみ全透過するフィルタ１１を介してスルーホール４
の欠陥を検知する光検知器２が設置されている。また、
上記両光検知器１０．１２の出力側にはコンパレータ１
３．１４、がそれぞれ接続されており、これらコンパレ
ータ１３．１４はそれぞれの光検知器１０又は１２がス
ルーホール４の位置又は欠陥を検知したとき、その出力
を「１」にするものであり、各コンパレータ１３．１４
の出力はアンド回路１５に入力され、このアンド回路１
５の論理条件が成立したとき、欠陥信号Ｓを送出するよ
うになっている。On one side of the printed board 1, a filter 5 that masks one end opening of the through hole 4 is closely arranged.This filter 5 only transmits light of a specific wavelength, for example, green light. It is something to do. In addition, on the side where the filter 5 is arranged, an illumination device 6 is arranged that emits both light that passes through the filter 5 (for example, green light) and light of a wavelength that does not pass through the filter 5, for example, red light. There is. Reference numeral 7 denotes a condensing lens placed on the other side of the printed board 1 facing the through hole 4 to be inspected, which condenses the light completely transmitted through the through hole 4. A through hole 4 is placed on the optical axis of 7 via a no-f mirror 8 and a filter 9 that transmits only green light.
A photodetector 10 is installed to detect the presence and position of the nozzle mirror 8, and a through hole 4 is installed on the optical axis reflected by the nof mirror 8 via a filter 11 that completely transmits only red light.
A photodetector 2 for detecting defects is installed. Also,
A comparator 1 is installed on the output side of both photodetectors 10 and 12 above.
3.14 are connected to each other, and these comparators 13.14 set their output to "1" when the respective photodetectors 10 or 12 detect the position or defect of the through hole 4, Each comparator 13.14
The output of is input to the AND circuit 15, and this AND circuit 1
When the logical condition No. 5 is satisfied, a defect signal S is sent out.

次に上記のように構成された本実施例の動作について説
明する。Next, the operation of this embodiment configured as described above will be explained.

プリント板１のスルーホール４０１つが検査位置に割出
された状態において、照明装置６から緑と赤色の光１６
がプリント板１の下面に向は照射されると、緑色の光が
スルーホール４をマスクしているフィルタ５を透過し、
スルーホール４内全通して集光レンズ７に達する。そし
て該緑色の透過光は集光レンズ７により集光され、ハー
フミラ−８全通してフィルタ９に投光される一方、ハー
フミラ−によシ反射されてフィルタ１１に投光される。With one through hole 40 of the printed board 1 indexed to the inspection position, green and red lights 16 are emitted from the illumination device 6.
When the lower surface of the printed board 1 is irradiated with green light, the green light passes through the filter 5 masking the through hole 4,
It passes completely through the through hole 4 and reaches the condenser lens 7. The transmitted green light is condensed by a condensing lens 7, passes through a half mirror 8, and is projected onto a filter 9, while being reflected by the half mirror and projected onto a filter 11.

ここで、フィルタ１１は緑色の光を通さないため、光検
知器１２は動作しない。一方、フィルタ９は緑色の光を
通すため、該光は光検知器１０により検知され、これに
より割出位置にスルーホール４があることを検知すると
同時に、スルーホール４の位置をも検知し、その信号を
コンバレ〜り１３に送出して、該コンパレータ１３の出
力を「１」にする。Here, since the filter 11 does not pass green light, the photodetector 12 does not operate. On the other hand, since the filter 9 passes green light, the light is detected by the photodetector 10, which detects the presence of the through hole 4 at the index position and simultaneously detects the position of the through hole 4, The signal is sent to the comparator 13, and the output of the comparator 13 is set to "1".

また、照明装置６からの赤色の光でプリント板１の下面
が照明されると、該光は基板材２内に入射し拡散される
。このとき、スルーホール４に鼾ンホール等の欠陥がな
ければ、拡散光はスルーホール４内に漏れることがなく
、従って光検知器１２も動作イれることがない。Further, when the lower surface of the printed board 1 is illuminated with red light from the illumination device 6, the light enters the substrate material 2 and is diffused. At this time, if there is no defect such as a snoring hole in the through hole 4, the diffused light will not leak into the through hole 4, and therefore the photodetector 12 will not malfunction.

しかるに、スルーホール４に欠陥３ａがあると、基板材
２内で拡散した光は欠陥３　’ａ　ｆ通してスルーホー
ル４内に漏れる。この光はレンズ７及びハーフミラ−８
にそれぞれのフィルタ９．１１に向は投射される。この
とき、フィルタ９は赤色の光を透過させないため、該光
によって光検知器１０が動作されないが、フィルタ１１
は赤色の光を透過させるため、該光は光検知器１２によ
°り検知され、これによシ検査位置に割出されたスルー
ホール４に欠陥があることを検知すると同時に、信号を
送出してコンパレータ１４の出力を「１」にする。コン
パレータ１３．１４の出力が共に「１」となってアンド
回路１５の論理条件が成立すると、検査位置に割出され
たスルーホール４に欠陥があると判定し、欠陥信号Ｓを
送出する。However, if there is a defect 3a in the through hole 4, the light diffused within the substrate material 2 leaks into the through hole 4 through the defect 3'af. This light is transmitted through lens 7 and half mirror 8.
are projected onto respective filters 9.11. At this time, since the filter 9 does not transmit red light, the photodetector 10 is not activated by the red light, but the filter 9
Since red light is transmitted through the through hole 4, the light is detected by the photodetector 12, which detects that there is a defect in the through hole 4 indexed to the inspection position, and at the same time sends out a signal. The output of the comparator 14 is set to "1". When the outputs of the comparators 13 and 14 both become "1" and the logical condition of the AND circuit 15 is satisfied, it is determined that there is a defect in the through hole 4 indexed to the inspection position, and a defect signal S is sent out.

また、検査位置へのスルーホール４の位置決めがなされ
なかったり、大幅にずれているようｆ：！場合は、基板
材２を透過する赤色の光が光検知器１２により検知され
たとしても欠陥信号Ｓが送出されることがない。Also, it seems that the through hole 4 is not positioned to the inspection position or is significantly misaligned f:! In this case, even if the photodetector 12 detects the red light transmitted through the substrate material 2, the defect signal S will not be sent out.

従って、上記のような本実施例にあっては、特定波長の
光のみを透過するフィルタ５にょクスルーホールをマス
クし、そしてこのマスク側から上記フィルタ５を透過す
る光と透過しない光の双方で照明し、スルーホール内を
透過する双方の光が光検知器にょシ検知されたとき欠陥
と判定するようにしたので、スル一ホールの欠陥の有無
検査が確実となり、その検査能率も向上できるほか、ス
ルーホールの有無及びその位置も検知できる。Therefore, in this embodiment as described above, the through hole in the filter 5 that transmits only light of a specific wavelength is masked, and both the light that passes through the filter 5 from the mask side and the light that does not pass through it. A defect is determined when both lights transmitted through the through-hole are detected by the photodetector, making it possible to reliably inspect the through-hole for defects and improve inspection efficiency. , the presence or absence of a through hole and its position can also be detected.

第２図は本発明の他の実施例を示すもので、第１図の場
合と同様にプリント板１に形成したスルーホール４の一
端開口を緑色の光のみを透過するフィルタ５によシマス
フし、そして）第２図（ａ）に示す如くまず緑色の光１
７にょυプリ。FIG. 2 shows another embodiment of the present invention, in which the opening at one end of a through hole 4 formed in a printed board 1 is screened by a filter 5 that transmits only green light, as in the case of FIG. 1. , and) As shown in Fig. 2(a), green light 1 is first emitted.
7 nyo υpuri.

ント板１の下面をフィルタ５側から照明し、フィルタ５
を透過する光をスルーホール対向位置　−に設けた光検
知器１８で検知してスルーホール４の有無及び位置を検
知する。次に、第２図（ｂ）に示す如く緑色の光に代え
て赤色の光１９によυプリント板１の下面を照明し、こ
のときスルーホール４に欠陥３ａがあれば、基板材２内
部に入射して拡散された光が欠陥３ａを通してスルーホ
ール４内に漏れ、この光を光検知器１８で検知する。The lower surface of the control plate 1 is illuminated from the filter 5 side, and the filter 5
The presence or absence and position of the through hole 4 is detected by detecting the light passing through the through hole 4 with a photodetector 18 provided at a position opposite to the through hole. Next, as shown in FIG. 2(b), the lower surface of the printed board 1 is illuminated with red light 19 instead of the green light, and if there is a defect 3a in the through hole 4, the inside of the board material 2 is illuminated. The light that is incident and diffused leaks into the through hole 4 through the defect 3a, and is detected by the photodetector 18.

この実施例にあっては、欠陥判定のための論理構成が上
記実施例のものより多少後Ｈになるが、その他は上記実
施例と同様な効果が得られる。In this embodiment, the logic configuration for defect determination is a little later than that of the above embodiment, but otherwise the same effects as the above embodiment can be obtained.

（７）０発明の詳細 な説明した通シ、本発明のスルーホール検査装置におい
ては、スルーホールの有無及び位置を検知できるととも
に欠陥の有無も検知でき、このため、スルーホールの欠
陥検知を確実にかつ正確にでき、検査能率も向上できる
効果がある。(7) In the detailed explanation of the invention, the through-hole inspection device of the present invention can detect the presence or absence of a through-hole and its position, as well as the presence or absence of a defect. Therefore, the through-hole defect can be detected reliably. This has the effect of improving inspection efficiency.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本発明にかかるプリント板のスルーホール検査
装置の一例を示す構成図、第２図（ａ）　、　（ｂ）は
本発明の他の実施を示す構成図である。 符号の説明 工はプリント板、２は基板材、４はスルーホール、５は
マスク用フィルタ、６は照明装置、８はハーフミラ−１
９，１１はフィルタ、１０，１２．１８は光検知器。 特許出願人　富士通株式会社FIG. 1 is a block diagram showing an example of a printed board through-hole inspection apparatus according to the present invention, and FIGS. 2(a) and 2(b) are block diagrams showing other embodiments of the present invention. The explanation of the symbols is printed board, 2 is the substrate material, 4 is the through hole, 5 is the mask filter, 6 is the illumination device, 8 is the half mirror 1
9, 11 are filters, 10, 12, and 18 are photodetectors. Patent applicant Fujitsu Limited

Claims (1)

【特許請求の範囲】[Claims] プリント板Ｖこ形成したスルーホールの一端開口を特定
波長の光のみを透過するフィルタによシマスフするとと
もに、このマスク面側から上記フィルタを透過する光と
該フィルタを透過しない光の双方を発する照明装置によ
り照明し、かつ上記マスク面と反対の側には、上記フィ
ルタを透過する光を検知してスルーホールの位Ｗ−＋検
知するための、及び上記フィルタを透過しない光を検知
することでスルーホールの欠陥を検知するための光検知
手段ｆ設けたことを特徴とするプリント板のスルーホー
ル検査装置。An illumination device in which an opening at one end of a through hole formed in a printed board V is covered with a filter that transmits only light of a specific wavelength, and from this mask surface side, both light that passes through the filter and light that does not pass through the filter are emitted. Illuminated by the device, and on the side opposite to the mask surface, for detecting the light passing through the filter to detect the through-hole position W-+, and for detecting the light not passing through the filter. A through-hole inspection device for a printed circuit board, characterized in that it is provided with a light detection means f for detecting defects in the through-holes.
JP22836982A 1982-11-30 1982-12-27 Apparatus for inspecting through-hole of printed circuit board Granted JPS59126233A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP22836982A JPS59126233A (en) 1982-12-27 1982-12-27 Apparatus for inspecting through-hole of printed circuit board
US06/554,543 US4560273A (en) 1982-11-30 1983-11-23 Method and apparatus for inspecting plated through holes in printed circuit boards
EP83307291A EP0111404B1 (en) 1982-11-30 1983-11-30 Method and apparatus for inspecting plated through holes in printed circuit boards
DE8383307291T DE3377527D1 (en) 1982-11-30 1983-11-30 Method and apparatus for inspecting plated through holes in printed circuit boards

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP22836982A JPS59126233A (en) 1982-12-27 1982-12-27 Apparatus for inspecting through-hole of printed circuit board

Publications (2)

Publication Number Publication Date
JPS59126233A true JPS59126233A (en) 1984-07-20
JPH0442622B2 JPH0442622B2 (en) 1992-07-14

Family

ID=16875379

Family Applications (1)

Application Number Title Priority Date Filing Date
JP22836982A Granted JPS59126233A (en) 1982-11-30 1982-12-27 Apparatus for inspecting through-hole of printed circuit board

Country Status (1)

Country Link
JP (1) JPS59126233A (en)

Also Published As

Publication number Publication date
JPH0442622B2 (en) 1992-07-14

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