JP2003281644A - Extinction type smoke sensor - Google Patents
Extinction type smoke sensorInfo
- Publication number
- JP2003281644A JP2003281644A JP2002086892A JP2002086892A JP2003281644A JP 2003281644 A JP2003281644 A JP 2003281644A JP 2002086892 A JP2002086892 A JP 2002086892A JP 2002086892 A JP2002086892 A JP 2002086892A JP 2003281644 A JP2003281644 A JP 2003281644A
- Authority
- JP
- Japan
- Prior art keywords
- light
- beam splitter
- reflecting mirror
- semi
- smoke
- 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
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
- Fire-Detection Mechanisms (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、発光部から受光部
に到達する光の減衰を検出して煙の存在を感知する減光
式煙感知器に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dimming smoke sensor for detecting the presence of smoke by detecting the attenuation of light reaching a light receiving portion from a light emitting portion.
【０００２】[0002]
【従来の技術】減光式煙感知器は、感知器本体の光源か
ら放出された光を感知器本体に向けて反射させる反射鏡
を有し、光の通過領域を監視空間として受光器が受光
し、上記監視空間に存在する煙によって減衰した光の減
衰量を測定することによって、火災を感知するものであ
る。このような減光式煙感知器においては、光路長が短
いと、受光量の減少として現れる減光量は、受光量に比
して非常に小さな値にしかならない。例えば光路長０．
１ｍの場合、減光率濃度１０％／ｍの煙での減光量は受
光量の１％程度にしかならない。2. Description of the Related Art A dimming type smoke detector has a reflecting mirror for reflecting light emitted from a light source of a sensor body toward the sensor body, and a light receiver receives the light passing region as a monitoring space. The fire is sensed by measuring the amount of light attenuated by the smoke existing in the monitoring space. In such a dimming smoke sensor, when the optical path length is short, the amount of dimming that appears as a decrease in the amount of received light is only a very small value compared to the amount of received light. For example, the optical path length is 0.
In the case of 1 m, the amount of extinction with smoke having an extinction ratio of 10% / m is only about 1% of the amount of received light.
【０００３】このため、減光式煙感知器においては、光
源から放射される光の経路を長くする必要があり、その
方法として複数の反射鏡により複数回反射させることに
より経路を長くしている。しかし、複数の反射鏡を用い
た場合には光が煙の粒子によって減衰されるだけでな
く、反射鏡の汚損によって減衰されることがある。そこ
で、汚損の影響を回避する方法として、例えば実公昭５
４−２６８６３号公報に開示された透過光式感知器の考
案がある。同公報の考案は、図４に示すように、複数枚
の反射鏡（Ｍ１〜Ｍ４）を感知器内に配置し、検出用光
源１及び検出用受光器３、参照用光源５及び参照用受光
器７を設け、光源１，５から受光器３，７までの反射回
数は同じであるが、検出用と参照用で光路の長さが異な
るようにして反射鏡の汚損の影響を回避しようというも
のである。Therefore, in the dimming type smoke sensor, it is necessary to lengthen the path of the light emitted from the light source, and as a method therefor, the path is lengthened by reflecting the light a plurality of times by a plurality of reflecting mirrors. . However, when a plurality of reflecting mirrors are used, not only the light is attenuated by smoke particles but also the stains of the reflecting mirrors may attenuate the light. Therefore, as a method of avoiding the influence of pollution, for example
There is a device of a transmitted light type sensor disclosed in the publication of 4-26863. In the device of the publication, as shown in FIG. 4, a plurality of reflecting mirrors (M1 to M4) are arranged in a sensor, and a detection light source 1 and a detection light receiver 3, a reference light source 5 and a reference light reception are provided. The number of reflections from the light sources 1 and 5 to the light receivers 3 and 7 is the same, but the lengths of the optical paths for detection and reference are different so as to avoid the influence of contamination of the reflecting mirror. It is a thing.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、上記の
従来技術においては、検出用と参照用で光路長を異なる
ように設定して反射鏡の汚損の影響を回避するという基
本思想はあるものの、具体的にいかにして影響を回避す
るかについては何等の開示もない。また、検出用光源１
及び参照用光源５といった検出用、参照用のそれぞれの
光源を要するため、装置構成が複雑になるという問題が
ある。さらに、検出用、参照用といったそれぞれ個別の
光源を用いるとこれらの汚損の影響を受けてしまうとい
う問題もある。However, in the above-mentioned prior art, although there is a basic idea that the optical path lengths for detection and reference are set differently to avoid the influence of contamination of the reflecting mirror, There is no disclosure about how to avoid the impact. In addition, the light source for detection 1
In addition, since the detection light source and the reference light source such as the reference light source 5 are required, there is a problem that the device configuration becomes complicated. Further, there is also a problem that the use of individual light sources for detection and reference causes the influence of these stains.
【０００５】本発明はかかる課題を解決するためになさ
れたものであり、反射鏡の汚損による影響を回避するた
めの具体的手段を備え、また装置構成が簡単で、さらに
光源の汚損の影響のない減光式煙感知器を提供すること
を目的としている。The present invention has been made in order to solve the above problems, and is provided with concrete means for avoiding the influence of stains on the reflecting mirror, and has a simple device configuration, and further the influence of stains on the light source. It is intended to provide no dimming smoke detector.
【０００６】[0006]
【課題を解決するための手段】本発明に係る減光式煙感
知器は、発光部と、ビームスプリッタと、半透過反射鏡
と、該半透過反射鏡を透過した光を受光する第１受光部
と、を直線状に配置するとともに、前記半透過反射鏡で
反射された光のうちビームスプリッタによって反射され
た光を受光する第２受光部を設けた減光式煙感知器であ
って、前記第１受光部による受光量と前記第２受光部に
よる受光量との比によって煙濃度を算出するものであ
る。A dimming type smoke sensor according to the present invention comprises a light emitting portion, a beam splitter, a semi-transmissive reflecting mirror, and a first light receiving device for receiving light transmitted through the semi-transmissive reflecting mirror. And a second light receiving section for linearly arranging the section and a second light receiving section for receiving the light reflected by the beam splitter among the light reflected by the semi-transmissive reflecting mirror, The smoke density is calculated by the ratio of the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit.
【０００７】また、発光部が直線偏光光源であり、ビー
ムスプリッタが偏光ビームスプリッタであるとともに、
半透過反射鏡の前面側に１／４波長板を配置したもので
ある。The light emitting section is a linearly polarized light source, the beam splitter is a polarized beam splitter, and
The quarter-wave plate is arranged on the front side of the semi-transmissive reflecting mirror.
【０００８】[0008]
【発明の実施の形態】実施の形態１．図１は本発明の一
実施の形態の説明図である。図において、１は光源、３
はビームスプリッタである。ビームスプリッタとは、光
線のある部分は反射し，他の部分は透過する反射鏡であ
る。５は検煙空間（光路長Ｌ）を介して設置された半透
過反射鏡、７は半透過反射鏡５によって透過された光を
受光する参照用受光器（第１受光部に相当）、９は半透
過反射鏡５によって反射され、さらにビームスプリッタ
３によって反射された光を受光する検出用受光器（第２
受光部に相当）である。BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. FIG. 1 is an explanatory diagram of an embodiment of the present invention. In the figure, 1 is a light source, 3
Is a beam splitter. A beam splitter is a reflecting mirror that reflects some light rays and transmits other light rays. Reference numeral 5 denotes a semi-transmissive reflecting mirror installed via the smoke detection space (optical path length L), 7 denotes a reference light receiver (corresponding to a first light receiving unit) for receiving the light transmitted by the semi-transmissive reflecting mirror 5, 9 Is a detection light receiver (second detector) that receives the light reflected by the semi-transmissive reflecting mirror 5 and further reflected by the beam splitter 3.
It corresponds to the light receiving portion).
【０００９】上記のように構成された減光式煙感知器に
おいて、光源１の光Ｐ０はビームスプリッタ３によって
透過光Ｐ１と反射光Ｐ１’に分離される。透過光Ｐ１は
検煙空間内にある煙によって減光されて半透過反射鏡５
の手前で光Ｐ２となる。光Ｐ２は半透過反射鏡５を透過
する透過光Ｐ３と、半透過反射鏡５によって反射される
反射光Ｐ４に分かれる。透過光Ｐ３は参照用受光器７に
よって受光され、他方、反射光Ｐ４は、再び検煙空間内
にある煙によって減光されてビームスプリッタ３の手前
で光Ｐ５となる。光Ｐ５はビームスプリッタ３によって
反射光Ｐ６と透過光Ｐ６’に分離され、反射光Ｐ６は検
出用受光器９によって受光される。In the dimming type smoke sensor constructed as described above, the light P0 from the light source 1 is separated by the beam splitter 3 into transmitted light P1 and reflected light P1 '. The transmitted light P1 is dimmed by smoke in the smoke detection space, and the semi-transmissive reflecting mirror 5
It becomes light P2 in front of. The light P2 is divided into a transmitted light P3 that passes through the semi-transmissive reflecting mirror 5 and a reflected light P4 that is reflected by the semi-transmissive reflecting mirror 5. The transmitted light P3 is received by the reference light receiver 7, while the reflected light P4 is attenuated again by smoke in the smoke detection space to become light P5 before the beam splitter 3. The light P5 is separated by the beam splitter 3 into reflected light P6 and transmitted light P6 ′, and the reflected light P6 is received by the detection light receiver 9.
【００１０】上記のように、光源１、ビームスプリッタ
３、半透過反射鏡５を直線状に配置することで、同一の
光源１から放射された光を、参照用は光路長をＬとし、
検出用の光の光路長は２Ｌとすることができる。こうす
ることで、光源１の汚損の影響を受けることなく、検出
用と参照用で光路長を異ならせることができ、かつ半透
過反射鏡５の汚損の影響をキャンセルできる。この、半
透過反射鏡５の影響をキャンセルできる点を以下におい
て具体的に説明する。As described above, by arranging the light source 1, the beam splitter 3, and the semi-transmissive reflecting mirror 5 linearly, the light emitted from the same light source 1 has an optical path length L for reference,
The optical path length of the detection light can be 2L. By doing so, the optical path length can be made different for detection and reference without being affected by the contamination of the light source 1, and the influence of the contamination of the semi-transmissive reflecting mirror 5 can be canceled. The fact that the influence of the semi-transmissive reflecting mirror 5 can be canceled will be specifically described below.
【００１１】ビームスプリッタ３と半透過反射鏡５の距
離をＬ、煙濃度をＫ％、半透過反射鏡５の透過率をα１
（０＜α≪１）、半透過反射鏡５の汚損による減光率を
β１、ビームスプリッタ３内損失をα２（０≪α２＜
１）、ビームスプリッタ３の汚損による減光率をβ２と
おくと、検出用受光器９に入射する光Ｐ６と、参照用受
光器７に入射する光Ｐ３の受光量はそれぞれ下式で表さ
れる。The distance between the beam splitter 3 and the semi-transmissive reflecting mirror 5 is L, the smoke density is K%, and the transmissivity of the semi-transmissive reflecting mirror 5 is α1.
(0 <α << 1), the extinction ratio due to the contamination of the semi-transmissive reflecting mirror 5 is β1, and the loss inside the beam splitter 3 is α2 (0 << α2 <
1) If the extinction ratio due to the contamination of the beam splitter 3 is β2, the light receiving amounts of the light P6 entering the detection light receiver 9 and the light P3 entering the reference light receiver 7 are expressed by the following equations, respectively. It
【００１２】[0012]
【数１】 [Equation 1]
【００１３】光Ｐ６と光Ｐ３の比をとると、下式のよう
になる。The ratio of the light P6 to the light P3 is given by the following equation.
【００１４】[0014]
【数２】 [Equation 2]
【００１５】上式（３）から分かるように、光Ｐ６と光
Ｐ３の比をとることで、半透過反射鏡５の汚損による減
光率β１の影響を完全にキャンセルできる。そして、半
透過反射鏡５の透過率α１、ビームスプリッタ内損失α
２は、光学素子固有の定数なので、予め求めることがで
きる。したがって、検出される光Ｐ６、光Ｐ３の受光量
を、式（３）に代入することで半透過反射鏡５の汚損に
よる減光率β１の影響を受けることなく煙濃度Ｋを求め
ることができる。そして、この煙濃度Ｋの値が所定の値
より大きいときに火災と判断する。もっとも、ビームス
プリッタ３で反射するのは検出用の光のみであり、この
ビームスプリッタ３の表面汚損による減光率β２の影響
は残ることになるが、この影響は煙のない平常状態にお
いても表れるので、学習によって補正可能である。つま
り、本実施の形態によれば、ビームスプリッタ３の表面
汚損による減光率β２のみを補正項目として考慮すれば
よいことになる。As can be seen from the above equation (3), by taking the ratio of the light P6 and the light P3, it is possible to completely cancel the influence of the extinction ratio β1 due to the contamination of the semi-transmissive reflecting mirror 5. Then, the transmittance α1 of the semi-transmissive reflecting mirror 5 and the loss α in the beam splitter
Since 2 is a constant unique to the optical element, it can be obtained in advance. Therefore, by substituting the received light amounts of the light P6 and the light P3 into the equation (3), the smoke density K can be obtained without being affected by the light reduction rate β1 due to the contamination of the semi-transmissive reflecting mirror 5. . Then, when the value of the smoke density K is larger than a predetermined value, it is determined that there is a fire. However, only the light for detection is reflected by the beam splitter 3, and the influence of the extinction ratio β2 due to surface contamination of the beam splitter 3 remains, but this influence also appears in a normal state without smoke. Therefore, it can be corrected by learning. That is, according to the present embodiment, only the extinction ratio β2 due to the surface contamination of the beam splitter 3 needs to be considered as the correction item.
【００１６】なお、実際の装置においては、参照用受光
器７、検出用受光器９で受光された光量は電気信号に変
換され、さらにマイクロコンピュータに入力されて、上
記（３）式に基づいて演算処理される。In an actual device, the light amount received by the reference light receiver 7 and the detection light receiver 9 is converted into an electric signal, which is further input to the microcomputer and based on the above equation (3). It is processed.
【００１７】上記の実施の形態における減光式煙感知器
は、光源１及びビームスプリッタ３を一つの筐体内設置
し、半透過反射鏡５及び参照用受光器７を別の筐体内に
設置し、検煙空間としては何等の仕切り等のない部屋の
空間とする別体型にすることができる。また、図２に示
すように、光源１及びビームスプリッタ３を収容する部
分１１と、半透過反射鏡５及び参照用受光器７を収容す
る部分１３と、検煙空間を囲むラビリンス１５とを一体
的に形成した一体型にすることもできる。In the dimming smoke detector according to the above embodiment, the light source 1 and the beam splitter 3 are installed in one housing, and the semi-transmissive reflecting mirror 5 and the reference light receiver 7 are installed in another housing. The smoke detection space can be a separate type of room space without any partitions. In addition, as shown in FIG. 2, a portion 11 that houses the light source 1 and the beam splitter 3, a portion 13 that houses the semi-transmissive reflecting mirror 5 and the reference light receiver 7, and a labyrinth 15 that surrounds the smoke detection space are integrated. Alternatively, it may be formed integrally.
【００１８】実施の形態２．実施の形態１においてはビ
ームスプリッタ３を用いたために、往路と復路において
それぞれＰ１’、Ｐ６’という無駄な光束を生じ、参照
用受光器５と検出用受光器９における受光量が小さくな
ってしまうという課題が残されていた。本実施の形態で
はこの課題を解決するものであり、Ｐ１’、Ｐ６’とい
う無駄な光束を生じさせないようにしたものである。Embodiment 2. Since the beam splitter 3 is used in the first embodiment, useless light fluxes P1 ′ and P6 ′ are generated in the forward path and the backward path, respectively, and the amount of light received by the reference light receiver 5 and the detection light receiver 9 becomes small. There was a problem left. In the present embodiment, this problem is solved, and the useless light fluxes P1 ′ and P6 ′ are not generated.
【００１９】図３は本発明の一実施の形態の説明図であ
り、図において実施の形態１と同一部分には同一の符号
を付している。本実施の形態が実施の形態１と異なる点
は、光源１に代えて直線偏光光源としてレーザ光源１７
を用いた点、ビームスプリッタ３に代えて偏光ビームス
プリッタ１９を用いた点、半透過反射鏡５の手前に１／
４波長板２１を設けた点である。FIG. 3 is an explanatory view of an embodiment of the present invention. In the figure, the same parts as those in the first embodiment are designated by the same reference numerals. The present embodiment is different from the first embodiment in that the laser light source 17 is used as a linearly polarized light source instead of the light source 1.
, A point using a polarization beam splitter 19 in place of the beam splitter 3, and 1 / in front of the semi-transmissive reflecting mirror 5.
This is the point where the four-wave plate 21 is provided.
【００２０】ここで、レーザ光源１７のような直線偏光
光源からは直線偏光、すなわち光の振動方向が一方向に
限られる（この例では紙面の上下方向に限られる）光を
放射する光源である。編光ビームスプリッタ１９とは、
複屈折性結晶を用いることにより偏光方向によって光を
透過させたり反射させたりする光学素子であり、この例
では紙面の上下方向の偏光は透過させ、紙面直角方向の
偏光は反射するように配置しているものである。１／４
波長板２１は一方向に振動する直線偏光が板を通過した
とき、これらの間にπ／２の位相差を与える複屈折板で
ある。Here, the linearly polarized light source such as the laser light source 17 is a light source which emits linearly polarized light, that is, light in which the vibration direction of light is limited to one direction (in this example, it is limited to the vertical direction of the paper surface). . What is the light beam splitter 19?
It is an optical element that transmits or reflects light depending on the polarization direction by using a birefringent crystal.In this example, it is arranged so that polarized light in the vertical direction of the paper surface is transmitted and polarized light in the direction perpendicular to the paper surface is reflected. It is what 1/4
The wave plate 21 is a birefringent plate that gives a phase difference of π / 2 between linearly polarized light vibrating in one direction when passing through the plate.
【００２１】上記のように構成された本実施の形態にお
いては、レーザ光源１７から放射された光Ｐ０（振動方
向は上下方向）は偏光ビームスプリッタ１９を通過して
光Ｐ１となり、検煙空間内にある煙によって減光されて
１／４波長板２１の手前で光Ｐ２となる。光Ｐ２は１／
４波長板２１を透過することで位相がπ／２ずれた光Ｐ
３となり、光Ｐ３は半透過反射鏡５によって透過光Ｐ４
と反射光Ｐ５に分かれる。透過光Ｐ４は参照用受光器７
によって受光される。反射光Ｐ５は再び１／４波長板２
１を透過することでさらに位相がπ／２ずれて紙面に垂
直方向に振動する光Ｐ６となる。光Ｐ６は再び検煙空間
内にある煙によって減光されて偏光ビームスプリッタ１
９の手前で光Ｐ７となり、光Ｐ７は偏光ビームスプリッ
タ１９によって全て反射されて光Ｐ８となって検出用受
光器９によって受光される。In the present embodiment configured as described above, the light P0 (the vibration direction is the vertical direction) emitted from the laser light source 17 passes through the polarization beam splitter 19 and becomes the light P1, which is in the smoke detection space. The light is dimmed by the smoke in the front and becomes light P2 before the quarter-wave plate 21. Light P2 is 1 /
Light P whose phase is shifted by π / 2 by passing through the four-wave plate 21
3, and the light P3 is transmitted by the semi-transmissive reflecting mirror 5 as light P4.
And reflected light P5. The transmitted light P4 is received by the reference light receiver 7
Is received by. The reflected light P5 is again converted into the quarter wave plate 2
By transmitting 1, the light is further shifted in phase by π / 2 to become light P6 that vibrates in the direction perpendicular to the paper surface. The light P6 is attenuated again by the smoke in the smoke detection space, and the polarized beam splitter 1
Light P7 is generated before 9, and the light P7 is totally reflected by the polarization beam splitter 19 and becomes light P8, which is received by the detection light receiver 9.
【００２２】以上のように、本実施の形態においては、
レーザ光源１７、偏光ビームスプリッタ１９及び１／４
波長板２１を用いることにより、実施の形態１で生じて
いたＰ１’、Ｐ６’という無駄な光束を生じさせること
がなく、減光量の検出を確実に行うことができる。As described above, in the present embodiment,
Laser light source 17, polarization beam splitter 19 and 1/4
By using the wave plate 21, it is possible to reliably detect the dimming amount without generating the useless luminous fluxes P1 ′ and P6 ′ generated in the first embodiment.
【００２３】なお、光源の汚損の影響を受けることなく
検出用と参照用で光路長を異ならせることができ、かつ
半透過反射鏡５の汚損の影響をキャンセルできる点は実
施の形態１と同様である。また、減光式煙感知器を別体
型、一体型にできる点も実施の形態１と同様である。As in the first embodiment, the optical path lengths for detection and reference can be made different without being affected by the contamination of the light source, and the influence of the contamination of the semi-transmissive reflecting mirror 5 can be canceled. Is. Further, the dimming type smoke sensor can be formed as a separate type or an integrated type as in the first embodiment.
【００２４】[0024]
【発明の効果】以上のように、本発明においては上記の
ように構成したので、以下のような効果を奏する。As described above, since the present invention is constructed as described above, the following effects can be obtained.
【００２５】発光部と、ビームスプリッタと、半透過反
射鏡と、該半透過反射鏡を透過した光を受光する第１受
光部と、を直線状に配置するとともに、前記半透過反射
鏡で反射された光のうちビームスプリッタによって反射
された光を受光する第２受光部を設けた減光式煙感知器
であって、前記第１受光部による受光量と前記第２受光
部による受光量との比によって煙濃度を算出するように
したことにより、反射鏡の汚損による影響を回避するこ
とができ、また装置構成が簡単で、さらに光源の汚損の
影響のない減光式煙感知器が実現できる。The light emitting portion, the beam splitter, the semi-transmissive reflecting mirror, and the first light receiving portion for receiving the light transmitted through the semi-transmissive reflecting mirror are linearly arranged and reflected by the semi-transmissive reflecting mirror. A reduced-light smoke sensor provided with a second light receiving portion for receiving the light reflected by the beam splitter among the received light, the light receiving amount by the first light receiving portion and the light receiving amount by the second light receiving portion. By calculating the smoke density based on the ratio, it is possible to avoid the effects of stains on the reflector, and the device configuration is simple, and a dimming smoke sensor that is not affected by stains on the light source is realized. it can.
【００２６】また、発光部が直線偏光を発光し、ビーム
スプリッタが偏光ビームスプリッタであるとともに、半
透過反射鏡の前面側に１／４波長板を配置したことによ
り、無駄な光束を生じさせることがなく、減光量の検出
を確実に行うことができる。Further, since the light emitting section emits linearly polarized light, the beam splitter is a polarizing beam splitter, and a quarter wavelength plate is arranged on the front side of the semi-transmissive reflecting mirror, a useless light beam is generated. Therefore, it is possible to reliably detect the dimming amount.
【図１】 本発明の一実施の形態の説明図である。FIG. 1 is an explanatory diagram of an embodiment of the present invention.
【図２】 本発明の一実施の形態における具体的態様を
示した図である。FIG. 2 is a diagram showing a specific mode in one embodiment of the present invention.
【図３】 本発明の他の実施の形態の説明図である。FIG. 3 is an explanatory diagram of another embodiment of the present invention.
【図４】 従来例の説明図である。FIG. 4 is an explanatory diagram of a conventional example.
１ 光源 ３ ビームスプリッタ ５ 半透過反射鏡 ７ 参照用受光器 ９ 検出用受光器 １７ レーザ光源 １９ 編光ビームスプリッタ ２１ １／４波長板 1 light source 3 beam splitter 5 Semi-transmissive reflector 7 Reference receiver 9 Detector for detection 17 Laser light source Chapter 19 Optical beam splitter 21 1/4 wave plate
Claims (2)
反射鏡と、該半透過反射鏡を透過した光を受光する第１
受光部と、を直線状に配置するとともに、前記半透過反
射鏡で反射された光のうちビームスプリッタによって反
射された光を受光する第２受光部を設けた減光式煙感知
器であって、 前記第１受光部による受光量と前記第２受光部による受
光量との比によって煙濃度を算出することを特徴とする
減光式煙感知器。1. A light emitting section, a beam splitter, a semi-transmissive reflecting mirror, and a first unit for receiving light transmitted through the semi-transmissive reflecting mirror.
A light-reducing smoke detector, comprising: a light-receiving part and a second light-receiving part for linearly arranging the light-receiving part and receiving the light reflected by the beam splitter among the light reflected by the semi-transmissive reflecting mirror. A smoke reduction smoke detector, wherein smoke density is calculated based on a ratio of the amount of light received by the first light receiving unit and the amount of light received by the second light receiving unit.
プリッタが偏光ビームスプリッタであるとともに、半透
過反射鏡の前面側に１／４波長板を配置したことを特徴
とする請求項１記載の減光式煙感知器。2. The light emitting section is a linearly polarized light source, the beam splitter is a polarizing beam splitter, and a quarter wavelength plate is arranged on the front side of the semi-transmissive reflecting mirror. Dimming smoke detector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002086892A JP2003281644A (en) | 2002-03-26 | 2002-03-26 | Extinction type smoke sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002086892A JP2003281644A (en) | 2002-03-26 | 2002-03-26 | Extinction type smoke sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003281644A true JP2003281644A (en) | 2003-10-03 |
Family
ID=29233326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002086892A Pending JP2003281644A (en) | 2002-03-26 | 2002-03-26 | Extinction type smoke sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2003281644A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108648409A (en) * | 2018-04-28 | 2018-10-12 | 北京环境特性研究所 | A kind of smog detection method and device |
-
2002
- 2002-03-26 JP JP2002086892A patent/JP2003281644A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108648409A (en) * | 2018-04-28 | 2018-10-12 | 北京环境特性研究所 | A kind of smog detection method and device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5085194B2 (en) | Method and system for adjusting the sensitivity of an optical sensor | |
| JP5373105B2 (en) | Miniature optical cell for miniaturized nuclear magnetic resonance gyroscope | |
| JP4446195B2 (en) | Laser beam output unit, laser beam input unit and laser gas analyzer | |
| JP2008527549A5 (en) | ||
| JP2002031685A (en) | Reflection measuring device | |
| JP2009145340A (en) | Laser rangefinder | |
| JP2018151278A (en) | Measurement device | |
| JP4807803B2 (en) | Gas content measuring apparatus and method | |
| JP2008070314A (en) | Gas detection apparatus | |
| JP2003281644A (en) | Extinction type smoke sensor | |
| JP2017110985A (en) | Gas detection device | |
| JP2003281643A (en) | Extinction type smoke sensor | |
| JP4893456B2 (en) | Position dimension measuring device | |
| JP2006133020A (en) | Laser beam emission device | |
| JP2006210826A (en) | Optical device, control method thereof, laser module, laser apparatus, control unit thereof, and control method of laser apparatus | |
| JP2010040006A (en) | Photoelectric smoke sensor and lighting apparatus | |
| JPH0827293B2 (en) | Liquid sensor | |
| JP2007093337A (en) | Photoelectric sensor | |
| JP6680098B2 (en) | Differential refractive index detector | |
| JP2002246636A (en) | Coaxial recursive reflection type photoelectric switch | |
| RU2454685C1 (en) | Gravitational wave detector | |
| RU2367984C1 (en) | Gravitation-wave detector | |
| JP2009063311A (en) | Gas detection device | |
| JP2004215315A (en) | Photo-electric sensor and sensitivity setting method therefor | |
| JP2002245912A (en) | Recurrent reflection plate with phase difference plate, photoelectric switch, and received light amount adjusting method |