JPH0682392A - Damage detector for transparent body - Google Patents
Damage detector for transparent bodyInfo
- Publication number
- JPH0682392A JPH0682392A JP23727292A JP23727292A JPH0682392A JP H0682392 A JPH0682392 A JP H0682392A JP 23727292 A JP23727292 A JP 23727292A JP 23727292 A JP23727292 A JP 23727292A JP H0682392 A JPH0682392 A JP H0682392A
- Authority
- JP
- Japan
- Prior art keywords
- transparent body
- light
- sensor
- refractive index
- transparent
- 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.)
- Pending
Links
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- Investigating Materials By The Use Of Optical Means Adapted For Particular Applications (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、建物や乗物の窓，ドア
あるいはショーケースなどに使われるガラスパネルや合
成樹脂パネル等の透明体の破損を検出するための装置に
関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting breakage of transparent bodies such as glass panels and synthetic resin panels used for windows and doors of buildings and vehicles, showcases and the like.
【０００２】[0002]
【従来の技術】窓ガラスのような透明体が用いられてい
る構造物において、防犯上の理由から各種のセンサが使
われている。例えば窓ガラスやショーウィンドが不審者
によって破壊されたことを検知するために、赤外線セン
サや光センサを窓ガラス等の近傍に設置し、何らかの物
体がセンサ光を横切った時に報知するシステムが知られ
ている。また、ドアや窓にリードスイッチを取付けるこ
とにより、ドアや窓の開閉を検出することも行われてい
る。2. Description of the Related Art Various sensors are used in a structure using a transparent body such as a window glass for crime prevention reasons. For example, there is known a system in which an infrared sensor or an optical sensor is installed in the vicinity of a window glass or the like in order to detect that a window glass or a show window is destroyed by a suspicious person, and notifies when an object crosses the sensor light. ing. In addition, opening / closing of the door or window is also detected by attaching a reed switch to the door or window.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、上記前
者の場合には、例えば展示中のショーケースのように不
特定多数の者がセンサに近寄ったりセンサ光を横切る可
能性がある場所には適用しにくいばかりでなく、虫や
犬，猫などがセンサ光を遮っても反応してしまうため、
本来の防犯機能を発揮できないことがある。However, the former case is not applicable to places where a large number of unspecified persons may approach the sensor or cross the sensor light, such as a showcase in an exhibition. Not only is it difficult, but insects, dogs, cats, etc. react even if they block the sensor light,
The original crime prevention function may not be exhibited.
【０００４】また、後者のようにリードスイッチによっ
てドアや窓の開閉を検出するシステムでは、ガラスを破
って侵入した者を検出できないとう問題があった。従っ
て本発明の目的は、ガラス等の透明体が割られたりひび
が入るなどの破損を検出できるような透明体の破損検出
装置を提供することにある。In the latter system, which detects the opening and closing of a door or a window by a reed switch, there is a problem that a person who breaks the glass and intrudes cannot be detected. Therefore, an object of the present invention is to provide a breakage detecting device for a transparent body that can detect breakage such as cracking or cracking of a transparent body such as glass.
【０００５】[0005]
【課題を解決するための手段】上記目的を果たすために
開発された本発明装置は、光透過性材料からなる透明体
の一端側に設けられてこの透明体の内部にセンサ光を投
射する発光素子を備えた投光部と、上記透明体の他端側
に設けられて上記センサ光を受光する受光素子を備えた
受光部と、上記受光素子によって受光されたセンサ光の
量が所定値以下であるか否かを判断する電気回路部とを
具備し、上記投光部は、透明体の屈折率をｎ1 ，透明体
に付着する液の屈折率をｎ2 とした時、sin θ＝ｎ2 ／
ｎ1 で表される臨界角θ以上の入射角でセンサ光を上記
透明体に入射させることを特徴とする。透明体はガラス
あるいは合成樹脂などからなり、無色透明でもよいし着
色されていてもよく、要するに光透過性材料からなるも
のであればよい。The device of the present invention developed to achieve the above object is a light emitting device which is provided at one end of a transparent body made of a light transmissive material and projects sensor light into the inside of the transparent body. A light projecting unit including an element, a light receiving unit provided on the other end side of the transparent body for receiving the sensor light, and an amount of the sensor light received by the light receiving device is equal to or less than a predetermined value. comprising an electrical circuit section that determines whether or not, the light projecting unit, n 1 the refractive index of the transparent body, when the refractive index of the liquid adhering to the transparent body and the n 2, sin θ = n 2 /
The sensor light is incident on the transparent body at an incident angle equal to or greater than the critical angle θ represented by n 1 . The transparent body is made of glass or synthetic resin and may be colorless and transparent or may be colored, that is, it may be made of a light transmissive material.
【０００６】[0006]
【作用】発光素子から上記入射角で透明体の内部に投射
されたセンサ光は、透明体が破損していなければ透明体
の内部において全反射を繰返すことによって受光部に向
かい、受光素子によって検出される。透明体の表面に水
などの液が付着しても、上記入射角で透明体に入射した
センサ光は、透明体と液との接触界面において外部に漏
れることなく全反射するため、所定光量のセンサ光が受
光素子に届く。The sensor light projected from the light emitting element to the inside of the transparent body at the above-mentioned incident angle goes to the light receiving section by repeating total reflection inside the transparent body unless the transparent body is damaged, and is detected by the light receiving element. To be done. Even if a liquid such as water adheres to the surface of the transparent body, the sensor light incident on the transparent body at the above incident angle is totally reflected at the contact interface between the transparent body and the liquid without leaking to the outside. The sensor light reaches the light receiving element.
【０００７】透明体が割れたり、ひびが入ると、透明体
の破損部においてセンサ光が外部に漏れたり、不特定方
向に反射するようになるため、受光素子に届く光量が減
少する。光量の低下は電気回路部によって検出され、所
定値以下の光量低下が検出された場合、透明体が破損し
たと判断され、警報を発する等の適当な措置がとられ
る。When the transparent body is cracked or cracked, the sensor light leaks to the outside at the damaged portion of the transparent body and is reflected in an unspecified direction, so that the amount of light reaching the light receiving element is reduced. The decrease in the amount of light is detected by the electric circuit unit, and when the amount of decrease in the amount of light below a predetermined value is detected, it is determined that the transparent body has been damaged, and appropriate measures such as issuing an alarm are taken.
【０００８】[0008]
【実施例】以下にこの発明の一実施例について、図１な
いし図３を参照して説明する。図１に示された透明体の
破損検出装置１０は、透明体１１の一例としてのガラス
板の一端側に設けられた投光部１２と、透明体１１の他
端側に設けられた受光部１３と、電気回路部１４などを
具備している。なお、投光部１２と受光部１３を複数対
設けるようにしてもよい。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The transparent body breakage detection device 10 shown in FIG. 1 includes a light projecting portion 12 provided on one end side of a glass plate as an example of the transparent body 11 and a light receiving portion provided on the other end side of the transparent body 11. 13 and an electric circuit section 14 and the like. A plurality of pairs of the light projecting unit 12 and the light receiving unit 13 may be provided.
【０００９】投光部１２は、例えば発光ダイオード等の
発光素子２０と、この発光素子２０を透明体１１に光学
的に接続する取付ベース２１とからなる。取付ベース２
１は透明体１１と同程度の屈折率の透明材料（この実施
例ではガラスと同程度の屈折率の材料）を使用し、透明
な接着材２２によって透明体１１に接着される。この接
着材２２も透明体１１と同程度の屈折率のものを使用す
る。The light projecting section 12 comprises a light emitting element 20 such as a light emitting diode, and a mounting base 21 for optically connecting the light emitting element 20 to the transparent body 11. Mounting base 2
1 is made of a transparent material having a refractive index similar to that of the transparent body 11 (a material having a refractive index similar to that of glass in this embodiment), and is bonded to the transparent body 11 by a transparent adhesive 22. The adhesive 22 also has the same refractive index as the transparent body 11.
【００１０】発光素子２０は透明体１１の内部にセンサ
光Ｒを投射するものであり、透明体１１の屈折率を
ｎ1 ，水の屈折率をｎ2 とした時、sin θ＝ｎ2 ／ｎ1
で表される臨界角θ以上の入射角θ′で透明体１１にセ
ンサ光Ｒを入射するよう、透明体１１に対する発光素子
２０の取付角度が設定されている。The light emitting element 20 projects the sensor light R into the inside of the transparent body 11. When the refractive index of the transparent body 11 is n 1 and the refractive index of water is n 2 , sin θ = n 2 / n 1
The mounting angle of the light emitting element 20 with respect to the transparent body 11 is set so that the sensor light R is incident on the transparent body 11 at an incident angle θ ′ that is greater than or equal to the critical angle θ.
【００１１】例えばガラスの屈折率ｎ1 を1.5 、水の屈
折率ｎ2 を1.33とすると、ガラスと水の接触界面におけ
る臨界角θは、sin θ＝1.33／1.5 ＝0.8867 となるよ
うなθであるから、この場合のθは62.5°となる。従っ
て、この例では約63°以上の入射角θ′で透明体１１に
センサ光Ｒを入射させるように、発光素子２０の取付角
度が設定される。なお、発光素子２０のセンサ光出射角
が広すぎる場合には、発光素子２０と取付ベース２１と
の間にレンズを設けることによって、収束されたセンサ
光Ｒを透明体１１に出射するようにしてもよい。For example, if the refractive index n 1 of glass is 1.5 and the refractive index n 2 of water is 1.33, the critical angle θ at the contact interface between glass and water is such that sin θ = 1.33 / 1.5 = 0.8867. Therefore, θ in this case is 62.5 °. Therefore, in this example, the mounting angle of the light emitting element 20 is set so that the sensor light R is incident on the transparent body 11 at an incident angle θ ′ of about 63 ° or more. When the sensor light emission angle of the light emitting element 20 is too wide, a lens is provided between the light emitting element 20 and the mounting base 21 so that the converged sensor light R is emitted to the transparent body 11. Good.
【００１２】受光部１３は、上記センサ光Ｒを受光する
フォトダイオード等を用いた受光素子３０と、受光素子
３０を透明体１１に光学的に接続する取付ベース３１を
備えている。取付ベース３１は透明体１１と同程度の屈
折率の透明材料（この実施例ではガラスと同程度の屈折
率の材料）を使用し、透明な接着材３２によって透明体
１１に接着されている。この接着材３２も透明体１１と
同程度の屈折率のものを使用する。The light receiving section 13 is provided with a light receiving element 30 using a photodiode or the like for receiving the sensor light R, and a mounting base 31 for optically connecting the light receiving element 30 to the transparent body 11. The mounting base 31 is made of a transparent material having a refractive index similar to that of the transparent body 11 (a material having a refractive index similar to that of glass in this embodiment), and is bonded to the transparent body 11 by a transparent adhesive material 32. The adhesive 32 also has the same refractive index as the transparent body 11.
【００１３】電気回路部１４は、マイクロコンピュータ
等を用いたコントローラであり、受光素子３０によって
受光されるセンサ光Ｒの光量が所定値以下になった時
に、透明体１１が破損したと判断し、警報器等の適宜の
防犯機器を作動させたり、警備室に通報するなどの信号
を送出するような電気的制御をなす。The electric circuit section 14 is a controller using a microcomputer or the like, and when the light quantity of the sensor light R received by the light receiving element 30 is below a predetermined value, it is judged that the transparent body 11 is damaged, Electrical control is performed such that an appropriate crime prevention device such as an alarm device is activated, or a signal is sent to notify the guard room.
【００１４】上記構成の実施例装置１０において、発光
素子２０から上記入射角θ′で透明体１１の内部に投射
されたセンサ光Ｒは、透明体１１の内部において全反射
を繰返すことによって受光部１３に向かい、受光素子３
０によって検出される。In the apparatus 10 of the embodiment having the above-mentioned structure, the sensor light R projected from the light emitting element 20 into the inside of the transparent body 11 at the incident angle θ'is repeatedly received in the inside of the transparent body 11 by repeating total reflection. 13 toward the light receiving element 3
Detected by 0.
【００１５】図３に示されるように、透明体１１にひび
が入ったり透明体１１が割れると、破損した箇所１１ａ
からセンサ光Ｒが漏れたり不特定方向に反射するため、
受光素子３０によって受光される光量が大幅に減少す
る。この光量低下が所定値を越えた時、透明体１１が破
損したとの判断がなされ、警報器等の適宜の機器を作動
させたり、警備室への通報がなされる。As shown in FIG. 3, when the transparent body 11 is cracked or the transparent body 11 is broken, the damaged portion 11a is broken.
Since the sensor light R leaks from or is reflected in an unspecified direction,
The amount of light received by the light receiving element 30 is significantly reduced. When the decrease in the amount of light exceeds a predetermined value, it is determined that the transparent body 11 has been damaged, an appropriate device such as an alarm device is activated, or a notification is sent to the guard room.
【００１６】なお、透明体１１の破損箇所から外部の照
明光や太陽光が入射する可能性がある場合には、周波数
変調されたセンサ光を受光素子３０によって検出させる
ことで、照明光や太陽光による増光の影響による誤判定
を防ぐようにしてもよい。When there is a possibility that external illumination light or sunlight enters from the damaged portion of the transparent body 11, the light-receiving element 30 detects the frequency-modulated sensor light to detect the illumination light or the sun. You may make it prevent the erroneous determination by the influence of the light increase by light.
【００１７】この実施例装置１０では、上記臨界角θ以
上の入射角θ′でセンサ光Ｒが入射されるから、雨や露
等によって透明体１１に水３５が付着したり、透明体１
１の上に水をこぼすなどしても、水３５と透明体１１
（この実施例ではガラス）との接触界面においてセンサ
光Ｒが全反射することができる。このため、水３５が付
着した箇所から光が漏れることがない。また、透明体１
１の表面に虫がとまったり、人や犬，猫などが透明体１
１に触れても誤動作を生じるおそれがなく、透明体１１
が破損した時のみ、警報動作等を実行することができ
る。In the apparatus 10 of this embodiment, the sensor light R is incident at an incident angle θ ′ that is equal to or greater than the critical angle θ, so that water 35 adheres to the transparent body 11 due to rain or dew, or the transparent body 1
Even if water is spilled on top of 1, the water 35 and the transparent body 11
The sensor light R can be totally reflected at the contact interface with (glass in this embodiment). Therefore, light does not leak from the place where the water 35 adheres. In addition, transparent body 1
Insects stop on the surface of 1 and people, dogs, cats, etc. are transparent 1
There is no risk of malfunction even when touching 1, and the transparent body 11
The alarm action can be executed only when the is damaged.
【００１８】なお、図４に示されるように、施錠装置４
０の近傍に発光部１２あるいは受光部１３を設ければ、
透明体１１が施錠装置４０の回りで割られたことを即座
に検出できるため、割れた箇所から手を入れて施錠装置
４０を開けるといった不審行為を防止する上で有効であ
る。As shown in FIG. 4, the locking device 4
If the light emitting portion 12 or the light receiving portion 13 is provided near 0,
Since it is possible to immediately detect that the transparent body 11 has been broken around the locking device 40, it is effective in preventing suspicious activity such as opening the locking device 40 by inserting a hand from a cracked portion.
【００１９】また、図５に示される破損検出装置５０の
ように、広がりのあるセンサ光Ｒを投射する投光部５１
を設けるとともに、透明体１１の対角線上に受光部５２
を配置し、更に受光部５２側に位置する透明体１１の縁
部５３，５４に導光部材６０を設けるようにしてもよ
い。導光部材６０は、縁部５３，５４に達したセンサ光
Ｒを受光素子３０に導く機能をもつ。この場合、導光部
材６０の適当な箇所にハーフミラー等の反射部６１を複
数設け、センサ光Ｒを受光素子３０に向って反射させる
ようにすれば、広い範囲にわたって透明体１１の破損を
検出することができる。Further, like the damage detecting device 50 shown in FIG. 5, a light projecting portion 51 for projecting the sensor light R having a spread.
And a light receiving section 52 is provided on the diagonal line of the transparent body 11.
May be disposed, and the light guide member 60 may be provided on the edge portions 53 and 54 of the transparent body 11 located on the light receiving portion 52 side. The light guide member 60 has a function of guiding the sensor light R reaching the edge portions 53 and 54 to the light receiving element 30. In this case, if a plurality of reflecting portions 61 such as half mirrors are provided at appropriate positions of the light guide member 60 and the sensor light R is reflected toward the light receiving element 30, the breakage of the transparent body 11 can be detected over a wide range. can do.
【００２０】[0020]
【発明の効果】本発明によれば、透明体が破損したこと
を報知することができ、防犯あるいは安全上優れた効果
を奏する。According to the present invention, it is possible to notify that the transparent body has been damaged, and there is an excellent effect in crime prevention or safety.
【図１】本発明の一実施例を示す破損検出装置の一部の
側面図。FIG. 1 is a side view of a part of a damage detection device showing an embodiment of the present invention.
【図２】図１に示された破損検出装置を備えた透明体の
斜視図。FIG. 2 is a perspective view of a transparent body including the damage detection device shown in FIG.
【図３】図１に示された破損検出装置において透明体が
破損した状態を示す側面図。FIG. 3 is a side view showing a state where the transparent body is broken in the breakage detection device shown in FIG.
【図４】施錠装置の近傍に破損検出装置を設けた実施例
を示す斜視図。FIG. 4 is a perspective view showing an embodiment in which a damage detection device is provided near the locking device.
【図５】本発明の他の実施例を示す破損検出装置を備え
た透明体の平面図。FIG. 5 is a plan view of a transparent body provided with a damage detection device showing another embodiment of the present invention.
１０…破損検出装置、１１…透明体、１２…投光部、１
３…受光部、１４…電気回路部、２０…発光素子、３０
…受光素子。10 ... Damage detection device, 11 ... Transparent body, 12 ... Projector, 1
3 ... Light receiving part, 14 ... Electric circuit part, 20 ... Light emitting element, 30
…Light receiving element.
Claims (1)
けられてこの透明体の内部にセンサ光を投射する発光素
子を備えた投光部と、上記透明体の他端側に設けられて
上記センサ光を受光する受光素子を備えた受光部と、上
記受光素子によって受光されたセンサ光の量が所定値以
下であるか否かを判断する電気回路部とを具備し、 上記投光部は、上記透明体の屈折率をｎ1 ，透明体に付
着する液の屈折率をｎ2 とした時、sin θ＝ｎ2 ／ｎ1
で表される臨界角θ以上の入射角でセンサ光を上記透明
体に入射させることを特徴とする透明体の破損検出装
置。1. A light projecting portion provided on one end side of a transparent body made of a light-transmissive material and provided with a light emitting element for projecting sensor light into the inside of the transparent body, and on the other end side of the transparent body. And a light receiving element having a light receiving element for receiving the sensor light, and an electric circuit section for determining whether or not the amount of the sensor light received by the light receiving element is less than or equal to a predetermined value. light unit, when n 1 the refractive index of the transparent body, the refractive index of the liquid adhering to the transparent body and the n 2, sin θ = n 2 / n 1
An apparatus for detecting damage to a transparent body, wherein sensor light is incident on the transparent body at an incident angle equal to or greater than the critical angle θ represented by.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23727292A JPH0682392A (en) | 1992-09-04 | 1992-09-04 | Damage detector for transparent body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23727292A JPH0682392A (en) | 1992-09-04 | 1992-09-04 | Damage detector for transparent body |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0682392A true JPH0682392A (en) | 1994-03-22 |
Family
ID=17012938
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23727292A Pending JPH0682392A (en) | 1992-09-04 | 1992-09-04 | Damage detector for transparent body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0682392A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR19990088623A (en) * | 1998-05-28 | 1999-12-27 | 가부시키가이샤 어드밴티스트 | Surface state monitoring method and apparatus |
| US6610994B1 (en) | 1997-07-17 | 2003-08-26 | Hoya Corporation | Method of checking unevenness of light-transmitting substance, apparatus therefor, and method of sorting transparent substrates |
| SG105576A1 (en) * | 2002-05-13 | 2004-08-27 | Zeiss Stiftung | Method and apparatus for detecting defects in a continuously moving strip of transparent material |
| WO2005064321A1 (en) * | 2003-12-30 | 2005-07-14 | Agency For Science, Technology And Research | Method and apparatus for detection of inclusions in glass |
| JP2007041312A (en) * | 2005-08-03 | 2007-02-15 | Hoya Corp | Method for manufacturing glass substrate for mask blank, method for manufacturing mask blank, method for manufacturing exposure mask, and defect inspection device |
| NL1025122C2 (en) * | 2002-12-27 | 2008-02-05 | Infineon Technologies Ag | Device and method for determining the physical properties of a raw mask. |
| JP2015174768A (en) * | 2014-03-18 | 2015-10-05 | 東芝エレベータ株式会社 | passenger conveyor |
-
1992
- 1992-09-04 JP JP23727292A patent/JPH0682392A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6610994B1 (en) | 1997-07-17 | 2003-08-26 | Hoya Corporation | Method of checking unevenness of light-transmitting substance, apparatus therefor, and method of sorting transparent substrates |
| KR19990088623A (en) * | 1998-05-28 | 1999-12-27 | 가부시키가이샤 어드밴티스트 | Surface state monitoring method and apparatus |
| SG105576A1 (en) * | 2002-05-13 | 2004-08-27 | Zeiss Stiftung | Method and apparatus for detecting defects in a continuously moving strip of transparent material |
| CN100350236C (en) * | 2002-05-13 | 2007-11-21 | 肖特股份有限公司 | Method and apparatus for detecting defects in a continuously moving strip of transparent material |
| NL1025122C2 (en) * | 2002-12-27 | 2008-02-05 | Infineon Technologies Ag | Device and method for determining the physical properties of a raw mask. |
| WO2005064321A1 (en) * | 2003-12-30 | 2005-07-14 | Agency For Science, Technology And Research | Method and apparatus for detection of inclusions in glass |
| US7511807B2 (en) | 2003-12-30 | 2009-03-31 | Agency For Science, Technology And Research | Method and apparatus for detection of inclusion in glass |
| JP2007041312A (en) * | 2005-08-03 | 2007-02-15 | Hoya Corp | Method for manufacturing glass substrate for mask blank, method for manufacturing mask blank, method for manufacturing exposure mask, and defect inspection device |
| JP4688150B2 (en) * | 2005-08-03 | 2011-05-25 | Ｈｏｙａ株式会社 | Mask blank glass substrate manufacturing method, mask blank manufacturing method, exposure mask manufacturing method, and defect inspection apparatus |
| JP2015174768A (en) * | 2014-03-18 | 2015-10-05 | 東芝エレベータ株式会社 | passenger conveyor |
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