JPH0523709B2 - - Google Patents
Info
- Publication number
- JPH0523709B2 JPH0523709B2 JP61153632A JP15363286A JPH0523709B2 JP H0523709 B2 JPH0523709 B2 JP H0523709B2 JP 61153632 A JP61153632 A JP 61153632A JP 15363286 A JP15363286 A JP 15363286A JP H0523709 B2 JPH0523709 B2 JP H0523709B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- section
- light receiving
- detection device
- field
- 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 - Lifetime
Links
- 238000001514 detection method Methods 0.000 claims description 31
- 239000004065 semiconductor Substances 0.000 claims description 9
- 239000002245 particle Substances 0.000 description 16
- 229910000077 silane Inorganic materials 0.000 description 8
- 230000004907 flux Effects 0.000 description 7
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 238000005259 measurement Methods 0.000 description 6
- 239000010419 fine particle Substances 0.000 description 5
- 239000000779 smoke Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 150000004756 silanes Chemical class 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
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
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/47—Scattering, i.e. diffuse reflection
- G01N21/49—Scattering, i.e. diffuse reflection within a body or fluid
- G01N21/53—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke
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)
- Fire-Detection Mechanisms (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Description
【発明の詳細な説明】
「産業上の利用分野」
この発明は、投光部により測定すべき気体に光
線を投光すると共に、前記投光部及び受光部の視
野の交叉部内に浮遊する微粒子からの散乱光を受
光部により受光して、前記気体中の微粒子を検知
する微粒子検知装置に関する。Detailed Description of the Invention "Industrial Application Field" The present invention projects a light beam onto a gas to be measured using a light projecting section, and detects fine particles floating within the intersection of the fields of view of the light projecting section and the light receiving section. The present invention relates to a particle detection device that detects particles in the gas by receiving scattered light from the air using a light receiving section.
「従来の技術」
従来、例えば半導体製造工場等においては、シ
ランガス（SiH4）が多用されている。しかし、
このシランガスは、空気中に放出されると自然燃
焼する性質を有しているため、配管からシランガ
スが漏洩した場合、設備機器等に延焼して大火災
に発展する恐れがある。従つて、シランガスを導
く配管が配設された区域内には、このシランガス
の漏洩を検知するガス漏れ検知装置を設置する必
要がある。"Prior Art" Conventionally, silane gas (SiH 4 ) has been widely used in, for example, semiconductor manufacturing factories. but,
Since this silane gas has the property of spontaneous combustion when released into the air, if the silane gas leaks from piping, there is a risk that the fire will spread to equipment and the like, leading to a major fire. Therefore, it is necessary to install a gas leak detection device for detecting leakage of this silane gas in the area where the piping for introducing the silane gas is installed.
従来、シランガスのガス漏れを検知する方法と
して、定電位電解式のセンサによつてシランガス
そのものを直接検知する方法や、シランガスの燃
焼に伴つて生成されるシリカ（SiO2）の煙粒子
（微粒子）を微粒子検知装置により検知する方法
等が知られている。 Conventional methods for detecting silane gas leaks include directly detecting the silane gas itself using a potentiostatic electrolytic sensor, and using smoke particles (fine particles) of silica (SiO 2 ) generated when silane gas is burned. There are known methods of detecting particles using a particle detection device.
第４図は、前記従来の微粒子検知装置の一例を
示す図である。第４図において、内部が黒色ペン
キの塗布等により乱反射抑制処理が施されている
殻体１には、一対のパイプ２，３が設けられてい
ると共に、一方のパイプ３が吸引側となつて、こ
の殻体１内に測定すべき気体が誘導される。ま
た、この殻体１内には、発光ダイオード等から構
成される投光部４、及びフオトトランジスタ等か
ら構成される受光部５が設けられ、投光部４から
投光される光線が、投光部４及び受光部５の視野
（光束）４ａ，５ａの交叉部６内に浮遊する煙粒
子（微粒子）により散乱され、この散乱光が受光
部５により受光されることで、この交叉部６内で
の煙粒子を有無及び濃度が検出される。 FIG. 4 is a diagram showing an example of the conventional particle detection device. In FIG. 4, a shell 1 whose interior has been subjected to diffuse reflection suppression treatment by applying black paint, etc., is provided with a pair of pipes 2 and 3, and one pipe 3 is on the suction side. , into which the gas to be measured is guided. Further, inside the shell 1, a light projecting section 4 composed of a light emitting diode or the like, and a light receiving section 5 composed of a phototransistor etc. are provided, and the light beam projected from the light projecting section 4 is projected. The field of view (luminous flux) 4a, 5a of the light section 4 and the light receiving section 5 is scattered by smoke particles (fine particles) floating in the intersection 6, and this scattered light is received by the light receiving section 5, so that the intersection 6 The presence and concentration of smoke particles within is detected.
近年、光強度の向上及び光束４ａの指向性の向
上を目的として、前記発光ダイオードの代わりに
半導体レーザーを投光部４に使用した微粒子検知
装置が検討されている。 In recent years, with the aim of improving the light intensity and the directivity of the light beam 4a, a particle detection device using a semiconductor laser in the light projecting section 4 instead of the light emitting diode has been studied.
「発明が解決しようとする問題点」
ところで、前記発光ダイオードを投光部４に使
用した微粒子検知装置では、この投光部４から投
光される光束４ａの断面形状が円形であるのに対
して、前記半導体レーザーを投光部４に使用した
微粒子検知装置では、半導体レーザーの構造的制
約等の理由により、投光部４の光束４ａ断面形状
が楕円状となる。このため、レーザー光の光束４
ａ断面の長軸４ｂと受光部５の受光視野５ａの中
心線５ｂとの位置関係により、受光部５における
散乱光受光面積が変化してしまい、第５図に示す
ように、前記光束４ａ断面の長軸４ｂと受光部５
の受光視野５ａの中心線５ｂとが略同一の面上に
位置する場合には、受光部５における散乱光受光
面積７が最小となつていた。そして、この場合、
受光部５により受光される前記交叉部６内の微粒
子からの散乱光が減少され、これが前記検知装置
自体の測定精度を低下させる要因となつていた。"Problems to be Solved by the Invention" By the way, in the particulate detection device using the light emitting diode in the light projecting section 4, the cross-sectional shape of the light beam 4a projected from the light projecting section 4 is circular. In the particle detection device using the semiconductor laser in the light projecting section 4, the cross-sectional shape of the light beam 4a of the light projecting section 4 becomes elliptical due to structural limitations of the semiconductor laser. For this reason, the luminous flux of the laser beam 4
Due to the positional relationship between the long axis 4b of the section a and the center line 5b of the light receiving field 5a of the light receiving section 5, the scattered light receiving area of the light receiving section 5 changes, and as shown in FIG. The long axis 4b and the light receiving part 5
When the center line 5b of the light-receiving visual field 5a and the center line 5b of the light-receiving field 5a are located on substantially the same plane, the scattered light receiving area 7 of the light-receiving section 5 is the minimum. And in this case,
The amount of scattered light received by the light receiving section 5 from the particles within the intersection section 6 is reduced, which has been a factor in reducing the measurement accuracy of the detection device itself.
この発明は、前記問題点に鑑みてなされたもの
で、その目的とするところは、受光部における散
乱光受光面積を最大にし、これにより測定精度が
十分向上された微粒子検知装置を提供することに
ある。 This invention was made in view of the above-mentioned problems, and its purpose is to provide a particulate detection device in which the scattered light receiving area in the light receiving section is maximized and measurement accuracy is thereby sufficiently improved. be.
「問題点を解決するための手段」
この発明は、半導体レーザーを用いた投光部
と、受光部とを有し、前記投光部により測定すべ
き気体にレーザー光線が投光されると共に、前記
投光部及び受光部の視野の交叉部内に浮遊する微
粒子からの散乱光が受光部により受光されること
で、前記気体中の微粒子が検知される微粒子検知
装置において、前記投光部から投光されるレーザ
ー光線の楕円状をなす光束断面の長軸が、前記交
叉部において前記受光部の受光視野の中心線と略
直交するように、これら投光部及び受光部を互い
に位置させたような微粒子検知装置を構成して、
前記問題点を解決している。"Means for Solving the Problems" The present invention has a light projecting section using a semiconductor laser and a light receiving section, and the light projecting section projects a laser beam onto the gas to be measured, and In the particulate detection device, in which particulates in the gas are detected by the light receiving part receiving scattered light from particulates floating within the intersection of the field of view of the light projecting part and the light receiving part, the light projecting part emits light. The light emitting part and the light receiving part are positioned relative to each other so that the long axis of the elliptical beam cross section of the laser beam is substantially perpendicular to the center line of the light receiving field of the light receiving part at the intersection part. Configure the sensing device to
This solves the above problems.
「実施例」
以下、この発明の実施例について図面を参照し
て説明する。"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings.
第１図は、この発明の一実施例である微粒子検
知装置を示す図である。なお、以下の説明におい
て、前記従来の微粒子検知装置と同一の構成要素
については同一の符号を付し、その説明を省略す
る。 FIG. 1 is a diagram showing a particulate detection device which is an embodiment of the present invention. In the following description, the same components as those of the conventional particulate detection device will be denoted by the same reference numerals, and the description thereof will be omitted.
第４図に示す前記従来の微粒敷検知装置と、こ
の発明の一実施例である微粒子検知装置との相異
点は、投光部４に半導体レーザーが使用されてい
ると共に、光束４ａ断面の長軸４ｂが、前記交叉
部６において受光部視野５ａの中心線５ｂと略直
交するように、これら投光部４及び受光部５が殻
体１内に配置されている点である。即ち、前記光
束４ａ断面の長軸４ｂの方向は、半導体レーザー
の投光部４内での回転により変化されるので、こ
の回転位置を適宜調整して前記長軸４ｂを受光部
視野５ａの中心線５ｂと略直交させるのである。 The difference between the conventional particulate detection device shown in FIG. 4 and the particulate detection device which is an embodiment of the present invention is that a semiconductor laser is used in the light projecting section 4, and the cross section of the light beam 4a is The light projecting section 4 and the light receiving section 5 are arranged in the shell 1 so that the long axis 4b is substantially perpendicular to the center line 5b of the field of view 5a of the light receiving section at the intersection 6. That is, since the direction of the long axis 4b of the cross section of the light beam 4a is changed by the rotation of the semiconductor laser within the light projecting section 4, this rotational position is appropriately adjusted to align the long axis 4b with the center of the field of view 5a of the light receiving section. It is made substantially perpendicular to the line 5b.
この微粒子検知装置の使用方法は、前記従来の
微粒子検知装置と同様である。ここで、投光部４
からの光束４ａ断面の長軸４ｂが、投光部４及び
受光部５の視野（光束）４ａ，５ａの交叉部６に
おいて、受光部視野５ａの中心線５ｂと略直交し
ているので、受光部５における散乱光受光面積７
が最大となる。従つて、前記交叉部６内に浮遊す
る微粒子からの散乱光が、前記受光部５により最
も効率良く受光されるため、検知装置自体の測定
精度が向上される。 The method of using this particle detection device is the same as that of the conventional particle detection device. Here, the light projecting section 4
Since the long axis 4b of the cross section of the light beam 4a from the light emitting section 4 and the light receiving section 5 intersect with the center line 5b of the field of view 5a at the intersection 6 of the field of view (luminous flux) 4a, 5a of the light receiving section 5, the light is received. Scattered light receiving area 7 in section 5
is the maximum. Therefore, the scattered light from the fine particles floating in the crossing section 6 is most efficiently received by the light receiving section 5, so that the measurement accuracy of the detection device itself is improved.
また、この実施例によれば、受光部５を投光部
４からの光束４ａに接近させることで、前記交叉
部６での散乱光の受光効率を向上させ、さらに検
知装置自体の測定精度を向上することが可能とな
る。すなわち、受光部５での前記散乱光の受光効
率は、投光部４の光束４ａと受光部５の視野５ａ
との成す角が大きいほど、また受光部５が前記投
光部４の光束４ａに近いほど向上される傾向にあ
るが、前記角度を大きくしたり、また受光部５を
前記光束４ａにあまり近付けたりすると、投光部
４からのレーザー光が直接受光部５で受光されて
しまうため、前記角度等には一定の限界がある。
特に、第２図に示すように、投光部４の光束４ａ
断面の長軸４ｂが、受光部５の受光視野５ａの中
心線５ｂと略同一の面上に位置する場合、平面視
した際に投光部光束４ａがより広がる結果とな
り、前記投光部光束４ａが直接受光部５に受光さ
れないように遮光板８を設置しても、必要以上に
受光部５を前記投光部光束４ａから離さざるを得
ず、このため受光部５での受光効率の向上が望み
にくい結果となつていた。しかし、この実施例で
ある微粒子検知装置では、第３図に示すように、
前記光束４ａ断面の長軸４ｂが、受光視野５ａの
中心線５ｂと略直交して位置されているので、平
面視した際に投光部光束４ａが絞り込まれたよう
な状態となり、このため遮光板８が同位置に配置
されていても、受光部５を投光部光束４ａに接近
させて位置させる（図示例においてl2＜l1）こと
が可能となり、これにより受光部５の受光効率を
向上させ、検知装置自体の測定精度を向上させる
ことが可能となる。 Further, according to this embodiment, by bringing the light receiving section 5 close to the light beam 4a from the light projecting section 4, the light receiving efficiency of the scattered light at the intersection section 6 is improved, and the measurement accuracy of the detection device itself is improved. It becomes possible to improve. That is, the light receiving efficiency of the scattered light at the light receiving section 5 is determined by the luminous flux 4a of the light projecting section 4 and the field of view 5a of the light receiving section 5.
The larger the angle formed by the light receiving part 5, and the closer the light receiving part 5 is to the light beam 4a of the light projecting part 4, the better the improvement will be. If this happens, the laser beam from the light projecting section 4 will be directly received by the light receiving section 5, so there is a certain limit to the angle and the like.
In particular, as shown in FIG.
When the long axis 4b of the cross section is located on substantially the same plane as the center line 5b of the light-receiving field 5a of the light-receiving part 5, the light emitting part light flux 4a becomes wider when viewed from above, and the light emitting part light flux Even if the light shielding plate 8 is installed so that the light beam 4a is not directly received by the light receiving section 5, the light receiving section 5 has to be separated from the light emitting section beam 4a more than necessary, which reduces the light receiving efficiency of the light receiving section 5. The result was that it was difficult to hope for improvement. However, in the particulate detection device of this embodiment, as shown in FIG.
Since the long axis 4b of the cross-section of the light beam 4a is positioned substantially perpendicular to the center line 5b of the light receiving field 5a, the light projector light beam 4a appears to be narrowed down when viewed from above, and therefore the light is blocked. Even if the plates 8 are arranged at the same position, it is possible to position the light receiving section 5 close to the light beam 4a of the light projecting section (l 2 < l 1 in the illustrated example), thereby increasing the light receiving efficiency of the light receiving section 5. This makes it possible to improve the measurement accuracy of the detection device itself.
なお、この発明である微粒子検知装置は、前記
実施例に限定されない。即ち、投光部４及び受光
部５の構成は、その使用用途等により周知の手段
から適宜選択されれば良い。また、この微粒子検
知装置は、前記の如く煙粒子の検知にその用途が
限定されることなく、気体中を浮遊する微粒子の
検出に好適な検知装置である。 Note that the particle detection device of the present invention is not limited to the above embodiments. That is, the configurations of the light projecting section 4 and the light receiving section 5 may be appropriately selected from known means depending on the intended use. Further, the application of this particulate detection device is not limited to the detection of smoke particles as described above, but is a detection device suitable for detecting particulates floating in gas.
「発明の効果」
以上詳細に説明したように、この発明によれ
ば、微粒子検知装置の、半導体レーザーを用いた
投光部から投光されるレーザー光線の楕円状をな
す光束断面の長軸が、前記投光部と受光部の視野
の交叉部において受光部の受光視野の中心線と略
直交するように、これら投光部及び受光部を互い
に位置させたので、前記受光部における散乱光受
光面積が最大となる。従つて、前記交叉部内に浮
遊する微粒子からの散乱光が、前記受光部により
最も効率良く受光されるため、検知装置自体の測
定精度が向上される、という優れた効果を奏す
る。"Effects of the Invention" As explained in detail above, according to the present invention, the long axis of the elliptical beam cross section of the laser beam projected from the light projection section using a semiconductor laser of the particulate detection device is Since the light emitting section and the light receiving section are mutually positioned so as to be substantially orthogonal to the center line of the light receiving field of the light receiving section at the intersection of the fields of view of the light emitting section and the light receiving section, the scattered light receiving area of the light receiving section is is the maximum. Therefore, the scattered light from the fine particles floating within the intersection portion is most efficiently received by the light receiving portion, which provides an excellent effect of improving the measurement accuracy of the detection device itself.
第１図はこの発明の一実施例である微粒子検知
装置を示す概略図、第２図は従来の微粒子検知装
置を平面視した概略図、第３図はこの発明の一実
施例である微粒子検知装置を平面視した概略図、
第４図は従来の微粒子検知装置の一例を示す概略
図、第５図は同他の例を示す概略図である。
４……投光部、４ａ……光束（視野）、４ｂ…
…長軸、５……受光部、５ａ……視野、５ｂ……
中心線、６……交叉部。
Fig. 1 is a schematic diagram showing a particulate detection device which is an embodiment of the present invention, Fig. 2 is a schematic diagram of a conventional particulate detection device viewed from above, and Fig. 3 is a particulate detection device which is an embodiment of the present invention. A schematic plan view of the device,
FIG. 4 is a schematic diagram showing an example of a conventional particle detection device, and FIG. 5 is a schematic diagram showing another example of the same. 4... Light projecting section, 4a... Luminous flux (field of view), 4b...
...Long axis, 5... Light receiving section, 5a... Field of view, 5b...
Center line, 6...intersection.
Claims (1)
が設けられ、前記投光部により測定すべき気体に
レーザー光線が投光されると共に、前記投光部及
び受光部の視野の交叉部内に浮遊する微粒子から
の散乱光が受光部により受光されることで、前記
気体中の微粒子が検知される微粒子検知装置にお
いて、前記投光部から投光されるレーザー光線の
楕円状をなす光束断面の長軸が、前記交叉部にお
いて前記受光部の受光視野の中心線と略直交する
ように、これら投光部及び受光部が互いに位置さ
れていることを特徴とする微粒子検知装置。1 A light emitting part using a semiconductor laser and a light receiving part are provided, and the light emitting part emits a laser beam onto the gas to be measured, and at the same time a laser beam is projected into the gas to be measured, and a laser beam is suspended within the intersection of the field of view of the light emitting part and the light receiving part. In a particulate detection device that detects particulates in the gas by receiving scattered light from particulates by a light receiving part, the long axis of an elliptical beam cross section of a laser beam projected from the light projecting part; The light projecting section and the light receiving section are positioned with respect to each other so as to be substantially perpendicular to the center line of the light receiving field of the light receiving section at the intersection portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15363286A JPS639848A (en) | 1986-06-30 | 1986-06-30 | Corpuscle detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15363286A JPS639848A (en) | 1986-06-30 | 1986-06-30 | Corpuscle detecting device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS639848A JPS639848A (en) | 1988-01-16 |
| JPH0523709B2 true JPH0523709B2 (en) | 1993-04-05 |
Family
ID=15566748
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15363286A Granted JPS639848A (en) | 1986-06-30 | 1986-06-30 | Corpuscle detecting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS639848A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009132025A (en) * | 2007-11-30 | 2009-06-18 | Ricoh Elemex Corp | Poor liquid delivery detecting apparatus |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6437732B2 (en) * | 2014-03-28 | 2018-12-12 | 能美防災株式会社 | smoke detector |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5084285A (en) * | 1973-11-26 | 1975-07-08 | ||
| JPS5487586A (en) * | 1977-12-16 | 1979-07-12 | Monitek Inc | Measuring device that measure light dispersed by branular body in fluid and photoodetector |
| JPS5942432A (en) * | 1982-09-01 | 1984-03-09 | Rion Co Ltd | Light scattering type floating particle counting apparatus |
| JPS59221640A (en) * | 1983-05-31 | 1984-12-13 | Matsushita Electric Works Ltd | Smoke sensor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0124616Y2 (en) * | 1978-05-11 | 1989-07-25 |
-
1986
- 1986-06-30 JP JP15363286A patent/JPS639848A/en active Granted
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5084285A (en) * | 1973-11-26 | 1975-07-08 | ||
| JPS5487586A (en) * | 1977-12-16 | 1979-07-12 | Monitek Inc | Measuring device that measure light dispersed by branular body in fluid and photoodetector |
| JPS5942432A (en) * | 1982-09-01 | 1984-03-09 | Rion Co Ltd | Light scattering type floating particle counting apparatus |
| JPS59221640A (en) * | 1983-05-31 | 1984-12-13 | Matsushita Electric Works Ltd | Smoke sensor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009132025A (en) * | 2007-11-30 | 2009-06-18 | Ricoh Elemex Corp | Poor liquid delivery detecting apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS639848A (en) | 1988-01-16 |
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