JPS62229209A - Photodetecting device - Google Patents
Photodetecting deviceInfo
- Publication number
- JPS62229209A JPS62229209A JP61073328A JP7332886A JPS62229209A JP S62229209 A JPS62229209 A JP S62229209A JP 61073328 A JP61073328 A JP 61073328A JP 7332886 A JP7332886 A JP 7332886A JP S62229209 A JPS62229209 A JP S62229209A
- Authority
- JP
- Japan
- Prior art keywords
- light
- filter
- optical
- light receiving
- optical fiber
- 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
Links
- 230000003287 optical effect Effects 0.000 claims abstract description 66
- 239000013307 optical fiber Substances 0.000 claims abstract description 31
- 230000001681 protective effect Effects 0.000 abstract description 9
- 230000005540 biological transmission Effects 0.000 description 8
- 238000010586 diagram Methods 0.000 description 3
- 239000000835 fiber Substances 0.000 description 3
- 239000005357 flat glass Substances 0.000 description 2
- 238000005253 cladding Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
Landscapes
- Optical Couplings Of Light Guides (AREA)
- Optical Communication System (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の技術分野１
本発明は、受光装置に関する・乙ので、詳しくは光波長
多重伝送システムにおける受光装置に関１ｙるものであ
る。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention 1] The present invention relates to a light receiving device, and specifically relates to a light receiving device in an optical wavelength division multiplexing transmission system.
［発明の技術的背景］
第１１図は光波長多重伝送システＩ＼における受イに側
の受光系を示したものである。[Technical Background of the Invention] FIG. 11 shows a receiving side light receiving system in an optical wavelength division multiplexing transmission system I\.
この受光系では、伝送路ａ内を伝わる波長多重光信号の
光量の一部が光分配器すによって取出され、その取出さ
れた波長多重光信号が光ファイバＣによって光分波器ｄ
ｉ、：ｉ？かれる。そしＣ１この波長多重光信号は、光
分波器ｄを通過１Ｊる際に、フィルタｅによって多重化
信号のうちの所定の波長域にある光信号λ１のみが取出
され、その所定の光信号が光ファイバＣ゛を経て受光素
子ｆに樽かれる。In this light-receiving system, a part of the light amount of the wavelength-multiplexed optical signal transmitted in the transmission path a is extracted by the optical splitter, and the extracted wavelength-multiplexed optical signal is transmitted through the optical fiber C to the optical demultiplexer d.
i, :i? It will be destroyed. Then, when this wavelength-multiplexed optical signal C1 passes through an optical demultiplexer d, only the optical signal λ1 in a predetermined wavelength range is extracted from the multiplexed signal by a filter e, and the predetermined optical signal is The light is connected to the light receiving element f via the optical fiber C'.
［費用技術の問題点］
ところで、このような受光系では、光分配器すと受光素
子ｒどの間の光ファイバに光分波器ｄをコネクタｃｈ、
（Ｊ’を介して接続している。[Problems with cost technology] By the way, in such a light receiving system, the optical demultiplexer d is connected to the optical fiber between the optical splitter and the light receiving element r.
(Connected via J'.
したがって、このような受光系では、部品点数が多くな
り、かつ系が大型化し、さらに光損失の増大も免れなか
った。Therefore, in such a light receiving system, the number of parts increases, the size of the system increases, and optical loss inevitably increases.
［発明の目的］
本発明の目的は、上記問題点に鑑みて、受光系から光部
品としての分波器を省ぎ、系の部品点数の削減、小型化
を図り、さらに系の光損失を可及的に減少することので
きる受光装置を提供することにある。[Object of the Invention] In view of the above-mentioned problems, the object of the present invention is to omit the demultiplexer as an optical component from the light receiving system, reduce the number of parts in the system, downsize it, and further reduce optical loss in the system. It is an object of the present invention to provide a light receiving device that can be reduced in size as much as possible.
［発明の概要１
本発明では、受光装置、叩ち光）７・イバの射出面から
受光素子の受光面までの間にフィルタを介在させ、もっ
て受光装置に所定の波長域にある信号を選択する光分波
は能をもたじている。[Summary of the Invention 1 In the present invention, a filter is interposed between the exit surface of the light-receiving device, the striking light) 7 and the light-receiving surface of the light-receiving element, and thereby the light-receiving device selects a signal in a predetermined wavelength range. The optical demultiplexing that is performed has the power.
この受光装置を採用すれば、受光系内の光部品としての
光分波器を省くことができる。If this light receiving device is adopted, an optical demultiplexer as an optical component in the light receiving system can be omitted.
［北門の実施例１
以下図面に示した実施例を参照しながら本発明を説明す
る。[Embodiment 1 of North Gate The present invention will be described below with reference to embodiments shown in the drawings.
第１図乃至第９図は、本発明に係る受光装置Ａ。1 to 9 show a light receiving device A according to the present invention.
Ｂ、・・・Ｉの各実施例を示したものである。各実施例
共に符号１は光ファイバ、符号２は受光素子、符号３は
レンズ、符号４はフィルタを示している。Each example of B, . . . I is shown. In each embodiment, reference numeral 1 indicates an optical fiber, reference numeral 2 a light receiving element, reference numeral 3 a lens, and reference numeral 4 a filter.
そして、各実施例の光ファイバ１は、フェルール等の保
護部材５によって囲まれている。The optical fiber 1 of each embodiment is surrounded by a protective member 5 such as a ferrule.
第１図に示した受光装置Ａは、光ファイバ１と受光素子
２との間にレンズ３を介在させたものである。そして、
この受光装置Ａでは、光）７・イバ１の出射面１ａおよ
び保護部材５の端面５ａを光軸に対して垂直に形成し、
それらの而１ａ、５ａに亘ってフィルタ４を貼設してい
る。この実施例の受光装置Ａでは、光フアイバ１内を伝
送されてきた波長多重光信号（λ１．λ２）は、フィル
タ４によって所定波長域の光信号λ１が選択され、その
選択された光信号λ１のみがレンズ３を介して受光素子
２の受光面２ａに入射される。一方、フィルタ４によっ
て除去された、即ちフィルタ４によって反射された光１
８号λ２は、光フアイバ１内を戻される。The light receiving device A shown in FIG. 1 has a lens 3 interposed between an optical fiber 1 and a light receiving element 2. The light receiving device A shown in FIG. and,
In this light receiving device A, the output surface 1a of the light beam 7 and the fiber 1 and the end surface 5a of the protective member 5 are formed perpendicular to the optical axis,
A filter 4 is pasted over these parts 1a and 5a. In the light receiving device A of this embodiment, the wavelength multiplexed optical signal (λ1, λ2) transmitted through the optical fiber 1 is filtered into an optical signal λ1 in a predetermined wavelength range, and the selected optical signal λ1 The light is incident on the light-receiving surface 2a of the light-receiving element 2 through the lens 3. On the other hand, the light 1 removed by the filter 4, i.e. reflected by the filter 4
No. 8 λ2 is returned within the optical fiber 1.
第２図に示した受光装置Ｂは、第１図に示した受光ｇｆ
ＨＡからレンズ３を取除いたもので、その他は第１図に
示した受光装置Ａと変るどころがない。したがって、受
光装置Ｂの作用は、受光装置Ａと同様である。The light receiving device B shown in FIG. 2 is similar to the light receiving device gf shown in FIG.
This is the same as the light receiving device A shown in FIG. 1 except that the lens 3 is removed from the HA. Therefore, the operation of light receiving device B is similar to that of light receiving device A.
第３図に示した受光装置Ｃは、第１図に示した受光装置
へにおけるフィルタ４を小さくし、そのフィルタ４°を
光フッ１イバ１の出射面１ａにのみ蒸着笠の方法で直接
貼設した・しので、その他は何ら☆るどころがない。し
たがって、受光装ＶＸＧの作用も、受光装置Ａと同様で
ある。In the light receiving device C shown in FIG. 3, the filter 4 in the light receiving device shown in FIG. Since I set it up, there is nothing else I can do about it. Therefore, the operation of the light receiving device VXG is also similar to that of the light receiving device A.
第４図に示した受光装置りは、光ファイバ１の出射面１
ａおよび保護部材５の端面５ａを光軸ど直交する面に対
して傾斜させて形成し、それらの面に頁ってフィルタ４
を貼設している。この受光Ｍｆ 習ｎ ｊ’−・ｌ＋
＊コ？Ｊ Ｊ ｒｃ １ＴＪ、ｌ 九ｊ？、 ：ソー
’Ｉ−？ ７ ＝？ ｊ−タ重化光信号（λ１．λ２）
は、フィルタ４によって所定波長域の光信号λ１が選択
され、その選択された光信号λ１のみがレンズ３を介し
て受光素子２の受光面２ａに入射される。一方、フィル
タ４によって除去された光信号λ２は、光ファイバ２の
クラッド部へ入射してしまい、伝送路内へは戻って行か
ない。The light receiving device shown in FIG.
a and the end face 5a of the protective member 5 are formed to be inclined with respect to a plane perpendicular to the optical axis, and the filter 4
is attached. This received light Mf xj'-・l+
*Ko? J J rc 1TJ, l 9j? , : So'I-? 7=? J-ta multiplexed optical signal (λ1.λ2)
An optical signal λ1 in a predetermined wavelength range is selected by the filter 4, and only the selected optical signal λ1 is incident on the light-receiving surface 2a of the light-receiving element 2 via the lens 3. On the other hand, the optical signal λ2 removed by the filter 4 enters the cladding portion of the optical fiber 2 and does not return into the transmission path.
第５図に示した受光ｇ置Ｅは、光ファイバ１と受光素子
２との間にレンズ３を介在させ、受光素子２の窓ガラス
２ｂにフィルタ４を貼着させたものである。この受光装
置［では、光フアイバ１内を伝送されてきた波長多重光
信号（λ１．λ２）は、光ファイバ１の出射面１ａから
出射され、レンズ３を経てフィルタ４に到達する。そし
て、その多重化光信号（λ１．λ２）は、フィルタ４に
よって所定波長域の光信号λ１が選択され、その選択さ
れた光信号λ１のみが受光素子２の受光面２ａに入射さ
れる。一方、フィルタ４によって除去された光信号λ２
は、レンズ３を経て放射され、保護部材５の端面５ａ等
で反０＝１されて４Ｅ ＩＫｒ六れ乙−第６図に示した
受光装置Ｆは、第５図に示した受光装置Ｅの受光素子２
を光軸と直交する面に対して傾斜させて設置した・ｂの
である。この受光装置「では、フィルタ４に到達した多
重化光信号（λ１．λ２）のうち、フィルタ４によって
除去された光信号λ２は、レンズ３を経ることなく放散
される。In the light-receiving position E shown in FIG. 5, a lens 3 is interposed between the optical fiber 1 and the light-receiving element 2, and a filter 4 is attached to the window glass 2b of the light-receiving element 2. In this light receiving device, the wavelength multiplexed optical signal (λ1, λ2) transmitted through the optical fiber 1 is emitted from the output surface 1a of the optical fiber 1, passes through the lens 3, and reaches the filter 4. Then, from the multiplexed optical signal (λ1, λ2), an optical signal λ1 in a predetermined wavelength range is selected by a filter 4, and only the selected optical signal λ1 is incident on the light-receiving surface 2a of the light-receiving element 2. On the other hand, the optical signal λ2 removed by the filter 4
is emitted through the lens 3, and is reversed by 0=1 at the end surface 5a of the protective member 5. Light receiving element 2
・b is installed so that it is inclined with respect to the plane perpendicular to the optical axis. In this light receiving device, among the multiplexed optical signals (λ1, λ2) that have reached the filter 4, the optical signal λ2 removed by the filter 4 is dissipated without passing through the lens 3.
第７図に示した受光装置Ｇは、第５図に示した受光装置
Ｅにおける光ファイバ１の出射面１ａおよび保護部材５
の端面５ａを光軸ど直交する而に対して傾斜させて形成
したものである。この受光装置Ｇでは、フィルタ４によ
って除去された光信号λ２が、レンズ３を経て光ファイ
バ１の出射面１ａまたは保護部材５の端面５ａに当って
も、それらの面１ａ、５ａが傾斜しているので、反射光
は、レンズ３を経て受光面２ａへ再入射することなく放
射される。The light receiving device G shown in FIG. 7 includes the output surface 1a of the optical fiber 1 and the protective member 5 in the light receiving device E shown in FIG.
The end face 5a of the lens is formed so as to be inclined with respect to the direction perpendicular to the optical axis. In this light receiving device G, even if the optical signal λ2 removed by the filter 4 passes through the lens 3 and hits the output surface 1a of the optical fiber 1 or the end surface 5a of the protective member 5, those surfaces 1a and 5a are tilted. Therefore, the reflected light is emitted without re-entering the light-receiving surface 2a via the lens 3.
第８図に示した受光装置Ｈは、光フ７・イバ１と受光素
子２との間にレンズ３を介在させたもので、そのレンズ
３の前面３ａにフィルタ４を貼着したものである。この
受光′Ａｔｆｆ１Ｈでは、光フアイバ１内を伝送されで
きた多重化光信号（λ１．λ２）は、光フ７・イバ１の
出射面１ａから出射され、フィルタ４に到達する。そし
て、その多重化光信号（λ１．λ２）は、フィルタ４に
よって所定波長域の光信号λ１が選択され、その選択さ
れた光信号λ１のみがレンズ４を経て受光索子２の受光
面２ａに入射される。一方、フィルタ４によって除去さ
れた光信号λ２は、保護部材５の端面５ａ等に突当った
りして拡散される。The light-receiving device H shown in FIG. 8 has a lens 3 interposed between the optical fiber 7 / fiber 1 and the light-receiving element 2, and a filter 4 is attached to the front surface 3a of the lens 3. . In this light reception 'Atff1H, the multiplexed optical signal (λ1, λ2) transmitted within the optical fiber 1 is emitted from the output surface 1a of the optical fiber 7/fiber 1 and reaches the filter 4. Then, from the multiplexed optical signal (λ1, λ2), the optical signal λ1 in a predetermined wavelength range is selected by the filter 4, and only the selected optical signal λ1 passes through the lens 4 and reaches the light receiving surface 2a of the light receiving cable 2. It is incident. On the other hand, the optical signal λ2 removed by the filter 4 hits the end surface 5a of the protection member 5, etc., and is diffused.
第９図に示した受光装置１は、レンズ３の背面３ｂにフ
ィルタ４を貼着したものである。この受光装置１では、
光フアイバ１内を伝送されてぎた多重化光信号（λ１．
λ２）は、光ファイバ１の、ＪｊＤＪ而１ａ面ら出射さ
れ、レンズ３を経てフィルタ４に到達する。そして、そ
の多重化光信号（λ１．λ２）は、フィルタ４によって
所定波長域の光４８号λ１が選択され、その選択された
光１８号λ１のみが受光素子２の受光面２ａに入射され
る。一方、フィルタ４によって除去された光信号λ２は
、再びレンズ３を経て、さらに保護部材５の端面５ａ等
に突当ったりして拡散されごく一部の光が光ファイバ１
へ再入射する。The light receiving device 1 shown in FIG. 9 has a filter 4 attached to the back surface 3b of a lens 3. In this light receiving device 1,
A multiplexed optical signal (λ1.
λ2) is emitted from the JjDJ plane 1a of the optical fiber 1 and reaches the filter 4 via the lens 3. Then, from the multiplexed optical signal (λ1, λ2), light No. 48 λ1 in a predetermined wavelength range is selected by the filter 4, and only the selected light No. 18 λ1 is incident on the light receiving surface 2a of the light receiving element 2. . On the other hand, the optical signal λ2 removed by the filter 4 passes through the lens 3 again, hits the end surface 5a of the protective member 5, etc., and is diffused, and a small portion of the light is transmitted to the optical fiber 1.
re-inject to.
そし℃、上記した受光装置Ａ−１は、第１０図に示した
ように受光系の一光部品として使用される。この受光系
では、伝送路ａ内を伝わる多重化信号（λ１．λ２）の
光量の一部が光分配器すによって取出され、その取出さ
れた多重化光信号（λ１．λ２）が光ファイバＣを経て
受光装置１１ｆｆＡ〜Ｉに入ｑ１される。そして、その
多重化光信号（λ１．λ２）は、受光装置Ａ−１のフィ
ルタ４によって所定波長域の光信号λ２が選択され、該
光信号λ２のみが受光素子３の受光面３ａに入ｑ１され
る。Then, the above-mentioned light receiving device A-1 is used as an optical component of a light receiving system as shown in FIG. In this light receiving system, a part of the light amount of the multiplexed signal (λ1, λ2) transmitted in the transmission path a is extracted by the optical splitter, and the extracted multiplexed optical signal (λ1, λ2) is transferred to the optical fiber C. The light then enters the light receiving devices 11ffA to 11ffq1. Then, from the multiplexed optical signal (λ1, λ2), an optical signal λ2 in a predetermined wavelength range is selected by the filter 4 of the light receiving device A-1, and only the optical signal λ2 enters the light receiving surface 3a of the light receiving element 3. be done.
［発明の効果］
上記したように、木北門に係る受光装置は、該装置内に
フィルタを付設しているので、光波長多重伝送シスデｔ
＼におりる受光系に、光部品としての光分波器を必要と
けず、したがって、受光系の小型化が泪れるばかっでな
く、：１ネクタによる光分波器と、光ファイバとの接続
箇所・し必要としないので、光ＪＣ１失を可及的に減少
１ｙることができる。。[Effects of the Invention] As described above, since the light receiving device according to Mokuhokumon is equipped with a filter, the optical wavelength division multiplexing transmission system t
There is no need for an optical demultiplexer as an optical component in the photodetection system, which not only allows for miniaturization of the photodetection system, but also enables the connection of an optical demultiplexer using a single connector and an optical fiber. Since no connection points are required, optical JC1 loss can be reduced as much as possible. .
第１図乃至第９図は本発明に係る受光装置の各実施例を
示した概念図、第１０図は本発明の受光装置を採用した
光波長多重伝送システムの受光系の要部を示した概念図
、第１１図は従来の光波長多重伝送システムの受光系の
要部を示した概念図である。
１・・・光ファイバ、１ａ・・・出射面、２・・・受光
索子２ａ・・・受光面、２ｂ・・・窓ガラス、３・・・
レンズ、３ａ・・・１１１１面、３ｂ・・・背面、４・
・・フィルタ、５・・・保護部材。
第１１図1 to 9 are conceptual diagrams showing each embodiment of a light receiving device according to the present invention, and FIG. 10 shows a main part of a light receiving system of an optical wavelength division multiplexing transmission system employing the light receiving device of the present invention. Conceptual diagram, FIG. 11 is a conceptual diagram showing the main parts of a light receiving system of a conventional optical wavelength division multiplexing transmission system. DESCRIPTION OF SYMBOLS 1... Optical fiber, 1a... Output surface, 2... Light receiving cable 2a... Light receiving surface, 2b... Window glass, 3...
Lens, 3a...1111 side, 3b...back, 4.
...filter, 5...protective member. Figure 11
Claims (6)
間に所定波長域の光を選択透過するフィルタを介在させ
たことを特徴とする受光装置。(1) A light-receiving device characterized by interposing a filter that selectively transmits light in a predetermined wavelength range between the output surface of the optical fiber and the light-receiving surface of the light-receiving element.
ことを特徴とする特許請求の範囲第（１）項記載の受光
装置。(2) The light receiving device according to claim (1), characterized in that the filter is brought into close contact with the output surface of the optical fiber.
して傾斜させて形成したことを特徴とする特許請求の範
囲第（２）項記載の受光装置。(3) The light receiving device according to claim (2), wherein the output surface of the optical fiber is formed to be inclined with respect to a plane perpendicular to the optical axis.
とを特徴とする特許請求の範囲第（１）項記載の受光装
置。(4) The light-receiving device according to claim (1), wherein the filter is brought into close contact with the light-receiving surface of the light-receiving element.
て傾斜させて配置したことを特徴とする特許請求の範囲
第（４）項記載の受光装置。(5) The light-receiving device according to claim (4), wherein the light-receiving surface of the light-receiving element is arranged to be inclined with respect to a plane perpendicular to the optical axis.
受光面との間に配置されたレンズの光透過面に密接させ
たことを特徴とする特許請求の範囲第（１）項記載の受
光装置。(6) Light receiving according to claim (1), characterized in that the filter is brought into close contact with the light transmitting surface of a lens disposed between the output surface of the optical fiber and the light receiving surface of the light receiving element. Device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61073328A JP2667389B2 (en) | 1986-03-31 | 1986-03-31 | Light receiving device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61073328A JP2667389B2 (en) | 1986-03-31 | 1986-03-31 | Light receiving device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62229209A true JPS62229209A (en) | 1987-10-08 |
| JP2667389B2 JP2667389B2 (en) | 1997-10-27 |
Family
ID=13514988
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61073328A Expired - Fee Related JP2667389B2 (en) | 1986-03-31 | 1986-03-31 | Light receiving device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2667389B2 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56147111A (en) * | 1980-04-17 | 1981-11-14 | Matsushita Electric Ind Co Ltd | Photocoupler |
| JPS58169124A (en) * | 1982-03-30 | 1983-10-05 | Fujitsu Ltd | Production of optical demultiplexer |
| JPS59158343U (en) * | 1983-04-08 | 1984-10-24 | 三菱電機株式会社 | light emitting diode module |
-
1986
- 1986-03-31 JP JP61073328A patent/JP2667389B2/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56147111A (en) * | 1980-04-17 | 1981-11-14 | Matsushita Electric Ind Co Ltd | Photocoupler |
| JPS58169124A (en) * | 1982-03-30 | 1983-10-05 | Fujitsu Ltd | Production of optical demultiplexer |
| JPS59158343U (en) * | 1983-04-08 | 1984-10-24 | 三菱電機株式会社 | light emitting diode module |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2667389B2 (en) | 1997-10-27 |
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