JPH04211203A - Dielectric multilayer film filter and manufacture thereof and optical element by use of this - Google Patents
Dielectric multilayer film filter and manufacture thereof and optical element by use of thisInfo
- Publication number
- JPH04211203A JPH04211203A JP3012277A JP1227791A JPH04211203A JP H04211203 A JPH04211203 A JP H04211203A JP 3012277 A JP3012277 A JP 3012277A JP 1227791 A JP1227791 A JP 1227791A JP H04211203 A JPH04211203 A JP H04211203A
- Authority
- JP
- Japan
- Prior art keywords
- filter
- dielectric multilayer
- thin film
- optical
- substrate
- 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.)
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Links
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- 239000000758 substrate Substances 0.000 claims abstract description 90
- 239000010408 film Substances 0.000 claims abstract description 77
- 239000010409 thin film Substances 0.000 claims abstract description 68
- 238000000034 method Methods 0.000 claims abstract description 30
- 239000000463 material Substances 0.000 claims abstract description 12
- 239000007788 liquid Substances 0.000 claims abstract description 11
- 238000007740 vapor deposition Methods 0.000 claims description 11
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims description 6
- 229910052731 fluorine Inorganic materials 0.000 claims description 6
- 239000011737 fluorine Substances 0.000 claims description 6
- 238000005520 cutting process Methods 0.000 claims description 4
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- 239000000835 fiber Substances 0.000 description 23
- 239000011521 glass Substances 0.000 description 20
- 239000000126 substance Substances 0.000 description 16
- GTDPSWPPOUPBNX-UHFFFAOYSA-N ac1mqpva Chemical compound CC12C(=O)OC(=O)C1(C)C1(C)C2(C)C(=O)OC1=O GTDPSWPPOUPBNX-UHFFFAOYSA-N 0.000 description 11
- 230000003595 spectral effect Effects 0.000 description 11
- 239000002253 acid Substances 0.000 description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 8
- 150000004985 diamines Chemical class 0.000 description 8
- 230000010287 polarization Effects 0.000 description 8
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- 238000010586 diagram Methods 0.000 description 7
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- 238000010168 coupling process Methods 0.000 description 6
- 238000005859 coupling reaction Methods 0.000 description 6
- 238000000926 separation method Methods 0.000 description 6
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 5
- 238000009826 distribution Methods 0.000 description 5
- 239000002985 plastic film Substances 0.000 description 5
- 229920006255 plastic film Polymers 0.000 description 5
- 238000004528 spin coating Methods 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 4
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- 229910052682 stishovite Inorganic materials 0.000 description 3
- 229910052905 tridymite Inorganic materials 0.000 description 3
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
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- 238000000869 ion-assisted deposition Methods 0.000 description 1
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Landscapes
- Optical Couplings Of Light Guides (AREA)
- Optical Integrated Circuits (AREA)
- Optical Filters (AREA)
- Paints Or Removers (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、光通信において用いら
れている誘電体多層膜干渉フィルタとこれを用いる部品
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric multilayer interference filter used in optical communications and parts using the same.
【０００２】0002
【従来の技術】光通信では、光路中の微小な間隙に薄い
誘電体多層膜フィルタを配設した部品が用いられ、これ
に必要な薄い誘電体多層膜フィルタが必要となる場合が
ある。図２１はその１例であって、光ファイバと光ファ
イバとの間に誘電体多層膜フィルタを挿入したものであ
る（Ｈ．Ｙａｎａｇａｗａ，ｅｔ．ａｌ．，‘Ｆｉｌｔ
ｅｒ−Ｅｍｂｅｄｄｅｄ Ｄｅｓｉｇｎ ａｎｄ
Ｉｔｓ Ａｐｐｌｉｃａｔｉｏｎｓ ｔｏ Ｐ
ａｓｓｉｖｅ Ｃｏｍｐｏｎｅｎｔｓ’ ，ＩＥＥ
ＥＪ．Ｌｉｇｈｔｗａｖｅ Ｔｅｃｈｎｏｌ．，ｖｏ
ｌ．ＬＴ−７，ｐｐ．１６４６−１６５３，１９８９）
。この図において、（ａ）は平面図、（ｂ）はＡ−Ａ’
に沿う断面図であって、符号１，２は光ファイバ、３は
誘電体多層膜フィルタ薄片、４は誘電体多層膜フィルタ
を配設するための溝、５は光ファイバと誘電体多層膜フ
ィルタを固定するための基板を示している。この構成に
よって、例えば誘電体多層膜フィルタ薄片３として波長
λ１の光を透過させ、波長λ２の光を反射させる特性の
ものを用いれば、光ファイバ１中を伝搬する２つの波長
成分λ１，λ２のうち不要な波長成分λ２のみを除去し
、必要な波長成分λ１のみを光ファイバ２に伝搬させる
ことができる。通常、入力ファイバの方向に反射して戻
る光を入力ファイバ２のクラッドに逃がすため、誘電体
多層膜フィルタは光ファイバの光軸垂直方向から所要角
度で傾けて配設する。このフィルタ入り光ファイバを作
製するには、まず基板５に予め設けた溝の中に光ファイ
バ１，２（この状態にあっては両光ファイバは切断され
ていない）を接着剤で固定する。次に、光ファイバを横
断する溝４を形成し、ここに誘電体多層膜フィルタ３を
挿入し、接着剤で固定する。
この方法からわかるように、光ファイバ１と光ファイバ
２は元々同一のファイバであり、また固定された状態で
切断されたのであるから、両者の光軸は一致しているの
で特に光軸合わせの必要は生じない。2. Description of the Related Art In optical communications, components are used in which thin dielectric multilayer filters are disposed in minute gaps in optical paths, and such thin dielectric multilayer filters may be required. Figure 21 is an example of this, in which a dielectric multilayer filter is inserted between optical fibers (H. Yanagawa, et. al., 'Filt
er-Embedded Design and
Its Applications to P
Assive Components', IEE
E.J. Lightwave Technology. ,vo
l. LT-7, pp. 1646-1653, 1989)
. In this figure, (a) is a plan view, (b) is A-A'
, numerals 1 and 2 are optical fibers, 3 is a dielectric multilayer filter thin piece, 4 is a groove for arranging the dielectric multilayer filter, and 5 is an optical fiber and a dielectric multilayer filter. It shows the board for fixing. With this configuration, for example, if a dielectric multilayer filter thin piece 3 that has the characteristics of transmitting light with a wavelength λ1 and reflecting light with a wavelength λ2 is used, the two wavelength components λ1 and λ2 propagating in the optical fiber 1 can be Among them, only the unnecessary wavelength component λ2 can be removed, and only the necessary wavelength component λ1 can be propagated to the optical fiber 2. Normally, in order to allow the light reflected back toward the input fiber to escape to the cladding of the input fiber 2, the dielectric multilayer filter is arranged at a predetermined angle from the direction perpendicular to the optical axis of the optical fiber. To manufacture this filter-containing optical fiber, first, optical fibers 1 and 2 (both optical fibers are not cut in this state) are fixed with adhesive in grooves previously provided in substrate 5. Next, a groove 4 is formed across the optical fiber, and the dielectric multilayer filter 3 is inserted therein and fixed with an adhesive. As can be seen from this method, optical fiber 1 and optical fiber 2 are originally the same fiber, and since they were cut in a fixed state, their optical axes coincide, so it is especially important to align the optical axes. No need arises.
【０００３】また、図２１のように単に直線状の光ファ
イバの途中ではなく、方向性結合器のような導波光を制
御する機能を持った素子の一部に誘電体多層膜フィルタ
を配設するものも考えられる。図２２はその例を示すも
のであって、この図において符号６，７は入力側光ファ
イバ、８，９は出力側光ファイバ、１０は方向性結合器
の光結合部、１１，１２は誘電体多層膜フィルタ薄片、
１３は誘電体多層膜フィルタを配設する溝、１４は光フ
ァイバと誘電体多層膜フィルタを固定するための基板を
示している。公知のように方向性結合器の結合度には波
長依存性があるため、例えば入力光ファイバ６を伝搬す
る２波長多重光のうち、一方の波長成分は光ファイバ８
から出力し、他方の波長成分は光ファイバ９から出力さ
れる。即ち、波長分離ができる。しかし、方向性結合器
単体だけでは波長分離度が十分でないため、出力ファイ
バ中に誘電体多層膜フィルタ薄片１１，１２を挿入する
構成が有効な手段となる。Furthermore, as shown in FIG. 21, a dielectric multilayer filter is disposed not only in the middle of a straight optical fiber, but also in a part of an element such as a directional coupler that has the function of controlling guided light. I can also think of something to do. FIG. 22 shows an example of this. In this figure, numerals 6 and 7 are input side optical fibers, 8 and 9 are output side optical fibers, 10 is an optical coupling part of a directional coupler, and 11 and 12 are dielectric fibers. Body multilayer membrane filter flakes,
Reference numeral 13 indicates a groove in which the dielectric multilayer filter is arranged, and reference numeral 14 indicates a substrate for fixing the optical fiber and the dielectric multilayer filter. As is well known, the degree of coupling of a directional coupler is wavelength dependent, so for example, of two wavelength multiplexed light propagating through the input optical fiber 6, one wavelength component is transmitted through the optical fiber 8.
The other wavelength component is output from the optical fiber 9. That is, wavelength separation can be performed. However, since a single directional coupler does not provide sufficient wavelength separation, an effective means is to insert dielectric multilayer filter thin pieces 11 and 12 into the output fiber.
【０００４】これらの他、図２１、図２２の光ファイバ
を光導波路に置き換えたもの等各種の構成が考えられる
。[0004] In addition to these, various other configurations are conceivable, such as one in which the optical fibers in FIGS. 21 and 22 are replaced with optical waveguides.
【０００５】以上示した従来例において、入力光ファイ
バを導波してきた光は溝内では回折のためにその強度分
布が広がり出力光ファイバには一部の光しか結合しない
。しかしフィルタを配設する溝幅を十分小さくすれば光
の損失を問題ない程度にまで小さくできる。例えば、光
ファイバとしてコア径１０μｍ、比屈折率差０．３％の
ものを用いる場合、溝幅を数十μｍ以下にすることによ
って、入力光ファイバと出力光ファイバの間隙によって
生じる回折損失を０．５ｄＢ程度に抑えることができる
。
即ち、これらの部品を低損失で実現するには、薄い誘電
体多層膜フィルタが必要である。In the conventional example described above, the light guided through the input optical fiber is diffracted within the groove, so that its intensity distribution is broadened, and only a portion of the light is coupled to the output optical fiber. However, if the width of the groove in which the filter is disposed is made sufficiently small, the loss of light can be reduced to an acceptable level. For example, when using an optical fiber with a core diameter of 10 μm and a relative refractive index difference of 0.3%, by reducing the groove width to several tens of μm or less, the diffraction loss caused by the gap between the input optical fiber and the output optical fiber can be reduced to 0. It can be suppressed to about .5 dB. That is, in order to realize these components with low loss, a thin dielectric multilayer filter is required.
【０００６】ところで、従来の誘電体多層膜フィルタは
、図２３に示すように、硬質の基板１５とその上に形成
された誘電体多層膜１６とから構成されている。基板１
５は、透明でかつ表面が平滑であり、またある程度の強
度が要求されるため、平板状の光学ガラス、例えば合成
石英ガラス、ＢＫ−７等の材料が用いられ、その厚さは
０．５ｍｍ以上である。また誘電体多層膜１６は、低屈
折率誘電体層１７と高屈折率誘電体層１８とを交互に積
層させたものである。また、誘電体層は２種類のみなら
ず、低屈折率誘電体と高屈折率誘電体とその間の屈折率
を持つ誘電体層を加えた３種類以上の誘電体物質を用い
たものもある。各層の膜厚は動作波長が大きくなるほど
厚くなり、要求される分光特性に近づけるためにより多
くの層を積み重ねる。光ファイバ通信でよく用いられる
波長域１．３１〜１．５５μｍのものでは、多層膜部の
総厚が１０μｍ前後に達するものもある。この従来のガ
ラスを基板とする誘電体多層膜フィルタにおいて厚さを
数十μｍ以下に薄くする場合、基板１５をその誘電体多
層膜１６が存在しない裏面から研磨して所望の厚さとし
、次いで所定の大きさに切断していた。By the way, as shown in FIG. 23, a conventional dielectric multilayer film filter is composed of a hard substrate 15 and a dielectric multilayer film 16 formed thereon. Board 1
5 is transparent and has a smooth surface, and is required to have a certain degree of strength, so flat optical glass, such as synthetic quartz glass, BK-7, etc., is used, and its thickness is 0.5 mm. That's all. Further, the dielectric multilayer film 16 is a film in which low refractive index dielectric layers 17 and high refractive index dielectric layers 18 are alternately laminated. In addition, the dielectric layer is not limited to two types, and some use three or more types of dielectric materials, including a low refractive index dielectric, a high refractive index dielectric, and a dielectric layer having a refractive index between them. The thickness of each layer increases as the operating wavelength increases, and more layers are stacked to approximate the required spectral characteristics. In the wavelength range of 1.31 to 1.55 μm, which is often used in optical fiber communications, the total thickness of the multilayer film portion may reach around 10 μm. In order to reduce the thickness of this conventional dielectric multilayer filter using glass as a substrate to several tens of micrometers or less, the substrate 15 is polished from the back surface where the dielectric multilayer film 16 is not present to a desired thickness, and then a predetermined thickness is obtained. It was cut to size.
【０００７】[0007]
【発明が解決しようとする課題】しかしながら、この薄
いフィルタを得る従来技術には大きく２つの欠点があっ
た。第１の欠点は、研磨や加工に熟練した人手を要し、
フィルタは極めて高価なものとなることが挙げられる。
さらにフィルタ全体としての厚さが数十μｍ以下となる
と、基板の厚さは極めて薄くなり割れ易く、表面の清浄
作業や取り付け作業に熟練した多大な労力を必要とする
。即ち、図２１や図２２のように簡単な構成であっても
、それに使用される誘電体多層膜フィルタが高価で、し
かも高度に熟練した人手を必要とするため、部品全体の
低価格化には限界があった。However, the conventional technique for obtaining this thin filter has two major drawbacks. The first drawback is that polishing and processing require skilled manpower.
One problem is that filters are extremely expensive. Furthermore, when the overall thickness of the filter is less than several tens of μm, the substrate becomes extremely thin and easily breaks, requiring a great deal of skilled labor for surface cleaning and attachment. That is, even with a simple configuration as shown in FIGS. 21 and 22, the dielectric multilayer filter used therein is expensive and requires highly skilled manpower, so it is difficult to reduce the price of the entire component. had its limits.
【０００８】従来技術の第２の欠点は、波長変動の無い
緻密な多層膜を得ようとして公知のイオンアシスト蒸着
法を用いると、多層膜内に圧縮性の応力が残りフィルタ
が反ってしまい、薄く研磨できなくなることである。こ
のことは例えば図２４の実測データから明らかである。
図２４は誘電体多層膜フィルタの多層膜面を上側にして
タリステップによって測定したもので、（Ａ）はイオン
アシスト法によるもので、（Ｂ）はイオンアシストを用
いない、通常の蒸着法によるものである。（Ａ），（Ｂ
）ともに基板には厚さ０．５ｍｍのＢＫ−７ガラス、多
層膜部は厚さ約１０μｍでＴｉＯ２とＳｉＯ２の交互層
からなり波長１．３μｍと１．５５μｍを分けるもので
ある。（Ａ）では多層膜面側が凸になるように大きく反
っていた。また（Ａ），（Ｂ）の湿度の変化（０〜１０
０％）に対する分光特性の変化を測定したところ、図２
５のような結果が得られた。（Ｂ）では湿度変化に対し
て波長が２５ｎｍも変化するのに対し、（Ａ）では極め
て安定な特性を示した。（Ｂ）において大きな湿度特性
を示したのは、多層膜内にある空孔に周囲の湿度に応じ
た水分が出入りし、それによって膜の屈折率が変化する
ためである。一方、（Ａ）において優れた耐湿特性を示
すのは、多層膜が緻密であるために水分の出入りを招く
ような空孔が存在しないためであるが、反面、緻密であ
ることは圧縮性応力の原因となる。The second drawback of the prior art is that when the known ion-assisted deposition method is used to obtain a dense multilayer film with no wavelength fluctuation, compressive stress remains within the multilayer film, causing the filter to warp. The problem is that it becomes impossible to polish thinly. This is clear from the measured data shown in FIG. 24, for example. Figure 24 shows measurements taken using Talystep with the multilayer surface of the dielectric multilayer filter facing upwards; (A) is measured using the ion assist method, and (B) is measured using the normal vapor deposition method without using ion assist. It is something. (A), (B
) In both cases, the substrate is BK-7 glass with a thickness of 0.5 mm, and the multilayer film portion is approximately 10 μm thick and consists of alternating layers of TiO 2 and SiO 2 to separate wavelengths of 1.3 μm and 1.55 μm. In (A), the multilayer film side was greatly warped so as to become convex. Also, the change in humidity of (A) and (B) (0 to 10
When we measured the change in spectral characteristics with respect to
5 results were obtained. In (B), the wavelength changed by as much as 25 nm due to changes in humidity, whereas in (A), extremely stable characteristics were exhibited. The reason that (B) showed a large humidity characteristic is that moisture enters and exits the pores in the multilayer film according to the surrounding humidity, which changes the refractive index of the film. On the other hand, the reason why (A) exhibits excellent moisture resistance is that the multilayer film is dense and does not have pores that would cause moisture to enter and exit. It causes
【０００９】そこで（Ａ），（Ｂ）の研磨加工性を調べ
たところ（Ａ）のものはばらばらに割れてしまい数十μ
ｍ以下の厚さのものは１つも得られなかった。一方、（
Ｂ）のものは２０μｍの厚さまで研磨が可能であった。
このような事情により、従来は研磨できる（Ｂ）のもの
が使用されていたが、取扱中や加工中あるいは保管中の
周囲の湿度変化に伴う波長変動を余儀なくされていた。[0009] When we investigated the polishing properties of (A) and (B), we found that (A) broke into pieces with a thickness of several tens of microns.
None with a thickness of less than m was obtained. on the other hand,(
B) could be polished to a thickness of 20 μm. Due to these circumstances, a polishable material (B) has been used in the past, but the wavelength has been forced to fluctuate due to changes in ambient humidity during handling, processing, or storage.
【００１０】そこで、先ず、上記従来品に変わる安価な
フィルタを得る方法として、本発明者らは、もともと薄
いプラスチックフィルム上に多層膜を形成する方法を検
討した。調査の結果、基板としてプラスチックフィルム
を用いその上に多層干渉膜を形成した試みが、例えば杉
山ら（特開昭６３−６４００３号公報、特開昭６３−８
８５０５号公報），Ｊ．Ａ．Ｄｏｂｒｏｗｏｌｓｋｉら
（Ａｐｐｌｉｅｄ Ｏｐｔｉｃｓ，ｖｏｌ．２８，ｎ
ｏ．１４，ｐ２７０２）によってなされている。これら
の例におけるフィルタでは可視域での使用を目的とし、
また要求される分光特性の精度もそれほど厳しいもので
はない。このため各層の膜厚、積層数はせいぜい０．２
μｍ、２０層程度である。前記の例では多層膜形成に、
フィルムの両端を巻き取り機構によって保持し、フィル
ムを真直に張った状態で膜形成を行う、いわゆるロール
塗工法が用いられている。しかしこの方法は、高精度に
制御された均一の膜厚の多層膜が得られない、多層膜が
形成されたフィルムを巻き取る際に多層膜が剥がれたり
、クラックが生じたりする。また基板となるフィルムは
ある程度の強度を持たせるための厚さが必要であり、事
実、前記杉山らの例ではポリエステルフィルムの厚さを
１００μｍとしている。これらを考慮に入れると、この
方法では本発明者らの目的とする誘電体多層膜フィルタ
は得られないと判断された。[0010] First, the inventors of the present invention investigated a method of forming a multilayer film on an originally thin plastic film as a method of obtaining an inexpensive filter in place of the conventional product. As a result of research, attempts were made to form a multilayer interference film on a plastic film using a plastic film as a substrate, for example, by Sugiyama et al.
8505), J. A. Dobrowolski et al. (Applied Optics, vol. 28, n.
o. 14, p2702). The filters in these examples are intended for use in the visible range,
Furthermore, the precision of the spectral characteristics required is not so strict. Therefore, the thickness of each layer and the number of laminated layers are at most 0.2
μm, about 20 layers. In the above example, for multilayer film formation,
A so-called roll coating method is used in which both ends of the film are held by a winding mechanism and film formation is performed with the film stretched straight. However, with this method, it is not possible to obtain a multilayer film with a uniform thickness that is controlled with high precision, and when the film on which the multilayer film is formed is wound up, the multilayer film may peel off or cracks may occur. Further, the film serving as the substrate needs to be thick enough to have a certain degree of strength, and in fact, in the example of Sugiyama et al., the thickness of the polyester film is 100 μm. Taking these into consideration, it was determined that the dielectric multilayer filter that the inventors aimed for could not be obtained by this method.
【００１１】そこで本発明者らはプラスチックフィルム
に高精度で高安定な多層膜を形成する方法を鋭意研究し
た結果、基板となるプラスチックフィルムにポリイミド
薄膜を用い、これを従来用いられているガラス等の基板
に密着形成させ、これを蒸着装置に設置しイオンアシス
ト法による多層膜を形成し、最後にガラス基板から剥す
方法を発明するに至った。ポリイミドはスピンコート等
の塗布法によって板状基板の上に密着形成ができ、また
その優れた耐熱性により蒸着時の温度上昇に耐えうるこ
とことから選ばれた。即ち、基板上に薄いポリイミド薄
膜が密着している点を除き、従来と同じ蒸着工程で同一
性能の多層膜を形成できる期待が持たれた。そこで市販
のポリイミド薄膜形成材料から厚さ０．５ｍｍのＢＫ−
７ガラス上にスピンコート法でポリイミド薄膜を形成し
、その上にイオンアシスト蒸着法によってＳｉＯ２とＴ
ｉＯ２からなる多層膜を形成した。多層膜とポリイミド
基板との付着は良好であった。しかし、最後に多層膜の
付着したポリイミド基板とＢＫ−７ガラスとを剥離する
工程において、ポリイミド薄膜とＢＫ−７ガラスとの密
着が強すぎて、剥離は不可能であった。The inventors of the present invention have conducted extensive research on a method for forming a highly accurate and highly stable multilayer film on a plastic film. As a result, they have used a polyimide thin film as a plastic film as a substrate, and compared it to conventionally used glass, etc. We have invented a method in which a multilayer film is formed by forming a multilayer film on a glass substrate by placing it in a vapor deposition apparatus using an ion-assisted method, and finally peeling it off from a glass substrate. Polyimide was selected because it can be closely formed on a plate-shaped substrate by a coating method such as spin coating, and its excellent heat resistance allows it to withstand temperature increases during vapor deposition. In other words, it was hoped that a multilayer film with the same performance could be formed using the same vapor deposition process as the conventional method, except that the thin polyimide film was in close contact with the substrate. Therefore, from a commercially available polyimide thin film forming material, BK-
7 A polyimide thin film is formed on glass by spin coating, and SiO2 and T are deposited on it by ion-assisted vapor deposition.
A multilayer film made of iO2 was formed. Adhesion between the multilayer film and the polyimide substrate was good. However, in the final step of peeling off the polyimide substrate to which the multilayer film was attached and the BK-7 glass, the adhesion between the polyimide thin film and the BK-7 glass was so strong that peeling was impossible.
【００１２】そこで、ガラス基板をより平面性の良いＳ
ｉ基板に替えその研磨面にポリイミド薄膜、多層膜を上
記と同様に形成した。多層膜が形成されたポリイミド薄
膜をナイフの刃先で徐々に剥したところ、かろうじて剥
離ができた。しかし、剥離したフィルタは直径数ｍｍに
カールし、極めて取扱の悪いものとなった。このカール
の方向は多層膜面が凸になる方向であった。カールした
原因として、用いたポリイミド薄膜の熱膨張係数が考え
られた。即ち、多層膜形成時にイオンの衝撃によって温
度が上昇したため（約２００℃）、ポリイミド薄膜の熱
膨張率（カタログ値で約２×１０ー５／℃）と多層膜の
熱膨張率（ＴｉＯ２とＳｉＯ２の熱膨張率の平均的な値
に近く０．４〜０．５×１０ー５／℃程度と予想される
）の差によって、室温に戻した状態ではポリイミド薄膜
の縮みが多層膜の縮みを上回り、これが多層膜部の圧縮
応力による反りをさらに助長した結果と推察された。事
実、得られたフィルムをホットプレート上で昇温させる
と、カールが戻る傾向が見られた。以上のことから、本
発明者らが当初発明した方法を実現するには、最終の工
程においてポリイミド薄膜と基板との剥離ができること
、反りを小さくすることが重要な要素であることが明ら
かとなった。[0012] Therefore, the glass substrate is made of S, which has better flatness.
Instead of the i-substrate, a polyimide thin film and a multilayer film were formed on the polished surface in the same manner as above. When the polyimide thin film on which the multilayer film was formed was gradually peeled off with the edge of a knife, it was barely peeled off. However, the peeled filter curled to a diameter of several mm, making it extremely difficult to handle. The direction of this curl was the direction in which the multilayer film surface became convex. The cause of the curling was thought to be the thermal expansion coefficient of the polyimide thin film used. That is, since the temperature rose (approximately 200°C) due to ion bombardment during the formation of the multilayer film, the coefficient of thermal expansion of the polyimide thin film (about 2 × 10-5/°C according to catalog value) and the coefficient of thermal expansion of the multilayer film (TiO2 and SiO2 Due to the difference in coefficient of thermal expansion, which is expected to be around 0.4 to 0.5 x 10-5/°C, which is close to the average value of the coefficient of thermal expansion of This is thought to be the result of further promoting warpage due to compressive stress in the multilayer film part. In fact, when the resulting film was heated on a hot plate, it tended to uncurl. From the above, it has become clear that in order to realize the method originally invented by the present inventors, it is important to be able to separate the polyimide thin film from the substrate in the final process and to reduce warpage. Ta.
【００１３】[0013]
【課題を解決するための手段】上記課題を解決するため
に、本発明者らは、基板としてフッ素化ポリイミド薄膜
を用い、かかるポリイミド薄膜基板上にイオンアシスト
蒸着による多層膜が形成された誘電体多層膜フィルタを
提案する。またこれを実現する製造方法として、液状の
フッ素化ポリイミド材料を表面が平滑な仮基板上に所要
の厚さに塗布し乾燥、硬化させてフッ素化ポリイミド薄
膜を形成し、このフッ素化ポリイミド薄膜上に誘電体多
層膜を形成した後、上記誘電体多層膜が表面に形成され
ているフッ素化ポリイミド薄膜を上記仮基板から剥離す
る方法を提案する。[Means for Solving the Problems] In order to solve the above problems, the present inventors used a fluorinated polyimide thin film as a substrate, and created a dielectric material on which a multilayer film was formed by ion-assisted vapor deposition on the polyimide thin film substrate. We propose a multilayer filter. In addition, as a manufacturing method to achieve this, a liquid fluorinated polyimide material is applied to the required thickness on a temporary substrate with a smooth surface, dried and cured to form a fluorinated polyimide thin film, and a fluorinated polyimide thin film is formed on this fluorinated polyimide thin film. A method is proposed in which a dielectric multilayer film is formed on the surface of the fluorinated polyimide thin film on which the dielectric multilayer film is formed, and then the fluorinated polyimide thin film on which the dielectric multilayer film is formed is peeled off from the temporary substrate.
【００１４】本発明による誘電体多層膜フィルタの作用
は、第１には基板を最初から薄膜化できるので従来の高
価な研磨工程を省略することができ、第２には多層膜が
イオンアシスト蒸着で形成されているため安定であり、
第３には基板が多層膜部よりも低熱膨張性であるために
、基板と多層膜の熱膨張率の差により、蒸着後に室温に
戻すとイオンアシスト蒸着膜の圧縮応力を打ち消し、反
りの少ないフィルタができることであり、第４には基板
にフッ素化ポリイミド薄膜を用いているために透明性が
あり、かつ仮基板から容易に剥離ができる。これらによ
って、薄い誘電体多層膜フィルタを用いるフィルタ部品
の安価な供給が可能となる。The functions of the dielectric multilayer film filter according to the present invention are as follows: Firstly, the substrate can be thinned from the beginning, so the conventional expensive polishing process can be omitted, and secondly, the multilayer film can be formed by ion-assisted vapor deposition. It is stable because it is formed of
Thirdly, because the substrate has lower thermal expansion than the multilayer film, the difference in thermal expansion coefficient between the substrate and the multilayer film cancels the compressive stress of the ion-assisted vapor deposition film when the temperature is returned to room temperature after vapor deposition, resulting in less warping. A filter can be formed.Fourthly, since a fluorinated polyimide thin film is used for the substrate, it is transparent and can be easily peeled off from the temporary substrate. These make it possible to supply filter components using thin dielectric multilayer filters at low cost.
【００１５】[0015]
【実施例】図１は、本発明に係わる誘電体多層膜フィル
タの実施例を示すもので、この図中符号１９はフィルタ
の基板となるフッ素化ポリイミド薄膜である。このフッ
素化ポリイミド薄膜１９の上面には、誘電体多層膜２０
が形成され、誘電体多層膜フィルタ２１が構成されてい
る。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of a dielectric multilayer filter according to the present invention, and reference numeral 19 in this figure indicates a fluorinated polyimide thin film serving as a substrate of the filter. A dielectric multilayer film 20 is formed on the upper surface of this fluorinated polyimide thin film 19.
is formed to constitute the dielectric multilayer filter 21.
【００１６】上記薄膜を形成するフッ素化ポリイミド（
以下、ポリイミドと略記する）は、化１に示す化学構造
式（１）〜（１５）で示す酸二無水物、および化２に示
す化学構造式（１）〜（３１）で示すジアミンとから合
成される。Fluorinated polyimide (
Polyimide (hereinafter abbreviated as polyimide) is composed of acid dianhydrides represented by chemical structural formulas (1) to (15) shown in chemical formula 1 and diamines represented by chemical structural formulas (1) to (31) shown in chemical formula 2. be synthesized.
【００１７】[0017]
【化１】[Chemical formula 1]
【化２】[Case 2]
【００１８】即ち、化１に示す酸二無水物、および化２
に示すジアミンの中から選ばれた酸二無水物の１種また
は数種と、ジアミンの１種または数種を、酸二無水物群
およびジアミン群がモル比で１：１になるように、Ｎ−
メチルピロリドン（ＮＭＰ）、Ｎ，Ｎ−ジメチルアセト
アミド（ＤＭＡｃ）などの極性溶媒中で反応させて得ら
れる液状のポリイミド材料（化学成分的には、ポリイミ
ドの前駆体であるポリアミド酸の溶液）、溶媒に可溶な
ポリイミドのポリアミド酸を加熱、脱水などのイミド化
処理により固体のポリイミドとした後、あるいはイミド
化処理中に溶媒に溶解した液状のポリイミド材料を用い
ることができる。That is, the acid dianhydride shown in chemical formula 1, and the acid dianhydride shown in chemical formula 2
One or more acid dianhydrides selected from the diamines shown in and one or more diamines such that the molar ratio of the acid dianhydride group and the diamine group is 1:1, N-
Liquid polyimide material obtained by reaction in a polar solvent such as methylpyrrolidone (NMP) or N,N-dimethylacetamide (DMAc) (in terms of chemical composition, a solution of polyamic acid, which is a precursor of polyimide), a solvent It is possible to use a liquid polyimide material obtained by converting the polyamic acid of polyimide soluble in polyimide into a solid polyimide by imidization treatment such as heating and dehydration, or by dissolving it in a solvent during the imidization treatment.
【００１９】この誘電体多層膜フィルタを製造するには
、図２（ａ）、（ｂ）、（ｃ）、（ｄ）に示す工程順に
よって行なわれる。即ち、まず表面が平滑な仮基板上に
液状のポリイミド材料を所要の厚さに塗布する。この塗
布は、均一の厚さに薄く塗布するため、スピンコートに
よって行う。次いで仮基板上に塗布した液状のポリイミ
ド材料を乾燥、硬化させ、図２（ａ）に示すようにポリ
イミド薄膜１９を形成する。次いで、図２（ｂ）に示す
ようにポリイミド薄膜１９の面に、イオンアシスト蒸着
法によって誘電体多層膜２０を形成する。次に、図２（
ｃ）に示すように、仮基板２２に届く程度の深さの切れ
目２３を形成し、最後に図２（ｄ）に示すように誘電体
多層膜フィルタを仮基板２２から剥離する。To manufacture this dielectric multilayer filter, the steps shown in FIGS. 2(a), 2(b), 2(c), and 2(d) are performed. That is, first, a liquid polyimide material is applied to a desired thickness onto a temporary substrate with a smooth surface. This application is performed by spin coating in order to apply a thin, uniform thickness. Next, the liquid polyimide material applied onto the temporary substrate is dried and cured to form a polyimide thin film 19 as shown in FIG. 2(a). Next, as shown in FIG. 2(b), a dielectric multilayer film 20 is formed on the surface of the polyimide thin film 19 by ion-assisted vapor deposition. Next, Figure 2 (
As shown in c), a cut 23 deep enough to reach the temporary substrate 22 is formed, and finally, the dielectric multilayer filter is peeled off from the temporary substrate 22 as shown in FIG. 2(d).
【００２０】また、剥離と切断の順序を入れ換え、図３
（ａ）、（ｂ）、（ｃ）、（ｄ）の工程順によって製造
しても良いが、この場合には図３（ｃ）において誘電体
多層膜フィルタ２１を剥離してから、同図（ｄ）におい
て切断する。In addition, the order of peeling and cutting was changed, and as shown in FIG.
Although manufacturing may be performed in the order of steps (a), (b), (c), and (d), in this case, after peeling off the dielectric multilayer filter 21 in FIG. 3(c), Cut at (d).
【００２１】上記図２（ａ）および図３（ａ）に示すポ
リイミド薄膜形成工程により得られたポリイミド薄膜１
９は、酸二無水物とジアミンの組み合わせに依存して線
膨張係数が−０．５〜１０×１０−５／℃となり光学多
層膜に使用する殆どの誘電体の熱膨張率をカバーできる
。またフッ素含有量の大小によって屈折率は１．５〜１
．７程度のガラスに近いものとなる。仮基板としては、
例えばシリコン、ＢＫ−７ガラス、石英ガラス、セラミ
ックス等が挙げられるが、最終的にフィルタには含まれ
ないので、安価なもの程良い。またフィルタの分光特性
の測定、検査のためには仮基板２２にフィルタ２１が付
着している図２（ｂ）もしくは図３（ｂ）の状態が強度
がある点で好都合であり、このためには測定、検査にお
いてフィルタの光学特性に影響を及ぼさない透明な仮基
板が望ましい。Polyimide thin film 1 obtained by the polyimide thin film forming process shown in FIGS. 2(a) and 3(a) above.
No. 9 has a linear expansion coefficient of -0.5 to 10 x 10-5/°C depending on the combination of acid dianhydride and diamine, and can cover the thermal expansion coefficient of most dielectrics used in optical multilayer films. Also, the refractive index varies from 1.5 to 1 depending on the fluorine content.
．． It is similar to glass of about 7. As a temporary board,
Examples include silicon, BK-7 glass, quartz glass, ceramics, etc., but since they are not included in the final filter, the cheaper the better. In addition, for measuring and inspecting the spectral characteristics of the filter, the state shown in FIG. 2(b) or FIG. 3(b), in which the filter 21 is attached to the temporary substrate 22, is convenient because of its strength. It is desirable to use a transparent temporary substrate that does not affect the optical characteristics of the filter during measurement and inspection.
【００２２】（実験例１）上記の製造方法に基づいて実
際に誘電体多層膜フィルタを製造した。直径３０ｍｍ、
厚さ０．５ｍｍのＢＫ−７（仮基板）上に化１の酸二無
水物（１）と、化２のジアミン（５）をＤＭＡｃ中で混
合し、反応させて得られたポリアミド酸溶液をスピンコ
ートし、オーブンを用いて７０℃で２時間、１６０℃で
１時間、２５０℃で３０分、さらに３５０℃で１時間の
乾燥、硬化処理を行って、下式化３に示すポリイミドと
した。(Experimental Example 1) A dielectric multilayer filter was actually manufactured based on the above manufacturing method. Diameter 30mm,
A polyamic acid solution obtained by mixing the acid dianhydride (1) of Chemical Formula 1 and the diamine (5) of Chemical Formula 2 in DMAc on BK-7 (temporary substrate) with a thickness of 0.5 mm and reacting them. was spin-coated and dried and cured in an oven at 70°C for 2 hours, 160°C for 1 hour, 250°C for 30 minutes, and 350°C for 1 hour to form the polyimide shown in Formula 3 below. did.
【００２３】[0023]
【化３】[Chemical formula 3]
【００２４】このポリイミドのフッ素含有量は化３から
２３％と計算された。得られたＢＫ−７上のポリイミド
薄膜はやや黄色味がかった色を呈していたが０．４〜１
．７μｍの波長域ではほぼ１００％の透過率を示した。
ポリイミド薄膜の厚さは約１０μｍ、屈折率は１．６１
（λ＝１．５３２μｍ）であった。その上に、イオンア
シスト蒸着法によってＴｉＯ２／ＳｉＯ２からなる多層
干渉膜約１０μｍを形成した。これにより得られた誘電
体多層膜フィルタの分光特性は図４に示すように光学ガ
ラス基板を用いたものと同等の特性を示し、またほぼ設
計通りのものであった。その他、図５に示す長波長域通
過形（１．３／１．５５μｍＬＷＰＦ）、図６に示す狭
帯域形（半値幅約４ｎｍ）もガラス基板のものと同等の
分光特性を示した。これらの特性から、ポリイミド薄膜
上に形成した多層膜の膜厚精度は従来のガラス基板を用
いたものと同等であることが確認された。さらに、ポリ
イミド薄膜上に形成された多層膜の周囲湿度に対する波
長変化も認められなかった。ポリイミド薄膜と多層膜と
の付着は、ピンセットの先で擦っても剥がれない程良好
であった。また、仮基板とポリイミド薄膜基板とは、通
常のハンドリングではなかなか剥がれない程に密着して
おり、３〜７日間水中に浸した後も密着性は低下しなか
った。しかし、ナイフの刃先等の薄い鋭利なものによっ
て端の方から容易に剥離ができ、直径３０ｍｍ、厚さ２
０μｍのほぼ平らなフィルタが得られた。仮基板から剥
離したフィルタの室温での反りは、多層膜面が凸になる
方向に僅かに反り、その半径は約０．３ｍであった。こ
のためハサミによる切断、ガラス上への接着が可能であ
った。反りの殆どないフィルタが得られたのは、特にこ
こで用いたポリイミド薄膜の熱膨張係数が負（約−０．
５×１０−５／℃）であるため、多層膜蒸着中の温度と
常温との温度差によってポリイミド薄膜の伸びが多層膜
の伸びより大きくなる効果が顕著に現れ、多層膜の圧縮
応力による曲げをほぼ完全に打ち消したためである。こ
のことは、仮基板から剥離したフィルタを、約１００℃
のホットプレート上に置くと反りが増加し、温度を室温
に戻すと反りの大きさが元に戻るような、いわゆるバイ
メタルのような振舞を示したことから実証された。The fluorine content of this polyimide was calculated from chemical formula 3 to be 23%. The polyimide thin film on BK-7 that was obtained had a slightly yellowish color, but it was 0.4 to 1
．． Almost 100% transmittance was exhibited in the 7 μm wavelength range. The thickness of the polyimide thin film is approximately 10 μm, and the refractive index is 1.61.
(λ=1.532 μm). Thereon, a multilayer interference film of about 10 μm consisting of TiO2/SiO2 was formed by ion-assisted vapor deposition. As shown in FIG. 4, the spectral characteristics of the dielectric multilayer filter thus obtained were equivalent to those using an optical glass substrate, and were almost as designed. In addition, the long wavelength pass type (1.3/1.55 μm LWPF) shown in FIG. 5 and the narrow band type (half width of about 4 nm) shown in FIG. 6 also showed spectral characteristics equivalent to those of the glass substrate. From these characteristics, it was confirmed that the film thickness accuracy of the multilayer film formed on the polyimide thin film is equivalent to that using a conventional glass substrate. Furthermore, no wavelength change was observed in the multilayer film formed on the polyimide thin film with respect to ambient humidity. The adhesion between the polyimide thin film and the multilayer film was so good that it did not peel off even when rubbed with the tips of tweezers. Further, the temporary substrate and the polyimide thin film substrate were in such close contact that they could not easily be separated by normal handling, and the adhesion did not deteriorate even after being immersed in water for 3 to 7 days. However, it can be easily peeled off from the edge with a thin sharp object such as the tip of a knife, and the diameter of 30 mm and thickness of 2.
A substantially flat filter of 0 μm was obtained. The filter peeled off from the temporary substrate was warped at room temperature slightly in the direction in which the multilayer film surface became convex, and the radius was about 0.3 m. Therefore, it was possible to cut it with scissors and adhere it to glass. The reason why we were able to obtain a filter with almost no warpage is that the polyimide thin film used here has a negative coefficient of thermal expansion (approximately -0.
5 x 10-5/℃), the elongation of the polyimide thin film becomes larger than the elongation of the multilayer film due to the temperature difference between the temperature during multilayer film deposition and the room temperature, and the bending due to the compressive stress of the multilayer film appears. This is because it almost completely canceled out the This means that the filter peeled off from the temporary substrate can be heated to approximately 100°C.
This was demonstrated by the fact that when placed on a hot plate, the warpage increased, and when the temperature was returned to room temperature, the warpage returned to its original size, exhibiting so-called bimetal-like behavior.
【００２５】次に、仮基板上のフィルタを、ダイシング
ソーによって流水しながら碁盤の目状に２ｍｍ角になる
ような切れ目を入れた。この切断においてもポリイミド
薄膜が仮基板から剥離することはなかった。しかし切断
された２ｍｍ角のチップは、ナイフの刃先等の薄い鋭利
なものによって破れることなく仮基板から容易に剥離が
できた。即ち、直径３０ｍｍの仮基板上に形成された誘
電体多層膜フィルタから大きさ２ｍｍ角、厚さ２０μｍ
のフィルタチップ約１５０個が容易に得られた。得られ
たフィルタチップの厚さをリニアゲージで１つ１つ測定
した結果、図７、図８に示す厚さ分布であった。ここで
、図７は図４に示す特性のフィルタ、図８は図５に示す
特性のフィルタである。図７、図８において最も頻度の
多い２１μｍ、１５μｍの厚さのものは直径３０ｍｍの
ウェハの中央部から得られたもので、これより厚いもの
は周辺部から得られたものである。厚さ分布は中心の値
に対して殆どのものが約±２μｍ以内に納まるもので、
ガラス基板を研磨する方法による精度と同程度であった
。このように高い膜厚均一性が得られたのは、ポリイミ
ド薄膜形成にスピンコート法を用いたことによる。尚、
１回のスピンコートでは１μｍ〜８０μｍのポリイミド
薄膜が得られるので用途に応じて厚さを選べることも確
認できた。Next, the filter on the temporary substrate was cut into 2 mm square cuts in a checkerboard pattern using a dicing saw while running water. Even during this cutting, the polyimide thin film did not peel off from the temporary substrate. However, the cut 2 mm square chip could be easily peeled off from the temporary substrate without being torn by a thin sharp object such as the edge of a knife. That is, from a dielectric multilayer filter formed on a temporary substrate with a diameter of 30 mm, a size of 2 mm square and a thickness of 20 μm is formed.
About 150 filter chips were easily obtained. The thickness of the obtained filter chips was measured one by one using a linear gauge, and the results showed the thickness distribution shown in FIGS. 7 and 8. Here, FIG. 7 shows a filter with the characteristics shown in FIG. 4, and FIG. 8 shows a filter with the characteristics shown in FIG. In FIGS. 7 and 8, the most frequent thicknesses of 21 μm and 15 μm were obtained from the center of a wafer with a diameter of 30 mm, and those thicker than this were obtained from the periphery. Most of the thickness distribution is within about ±2 μm from the center value,
The accuracy was comparable to that obtained by polishing a glass substrate. The reason why such high film thickness uniformity was obtained is that a spin coating method was used to form the polyimide thin film. still,
Since a polyimide thin film of 1 μm to 80 μm can be obtained by one spin coating, it was confirmed that the thickness could be selected depending on the application.
【００２６】（実験例２）化１の酸二無水物（５）と化
２のジアミン（１３）をＤＭＡｃ中で反応させて得られ
た液状のポリイミド材料を用いた以外は実験例１と同じ
にして誘電体多層膜フィルタを作製した。この場合にお
けるポリイミドは、下式化４の構造を有し、そのフッ素
含有量は１１％、熱膨張係数は１×１０ー６／℃であっ
た。(Experimental Example 2) Same as Experimental Example 1 except that a liquid polyimide material obtained by reacting the acid dianhydride (5) of Chemical Formula 1 and the diamine (13) of Chemical Formula 2 in DMAc was used. A dielectric multilayer filter was fabricated using the following method. The polyimide in this case had the structure shown in Formula 4 below, had a fluorine content of 11%, and a coefficient of thermal expansion of 1×10 −6 /° C.
【００２７】[0027]
【化４】[C4]
【００２８】仮基板から剥離した誘電体多層膜フィルタ
の反りは実験例１の場合よりやや大きかったが十分に使
用できるものであった。Although the warpage of the dielectric multilayer filter peeled off from the temporary substrate was slightly larger than that in Experimental Example 1, it was still usable.
【００２９】（比較例）化１の酸二無水物（４）と化２
のジアミン（５）をＤＭＡｃ中で反応させて得られた液
状のポリイミドを用いた以外は実験例１と同じにして誘
電体多層膜フィルタを作製した。この場合におけるポリ
イミドは下式化５の構造をし、フッ素含有量が３１％と
大きく、可視域でも透明で、屈折率も１．５とガラスの
特性に近いものであった。(Comparative example) Acid dianhydride (4) of chemical formula 1 and chemical formula 2
A dielectric multilayer filter was produced in the same manner as in Experimental Example 1, except that a liquid polyimide obtained by reacting diamine (5) in DMAc was used. The polyimide in this case had the structure shown in Formula 5 below, had a high fluorine content of 31%, was transparent even in the visible range, and had a refractive index of 1.5, which was close to the properties of glass.
【００３０】[0030]
【化５】[C5]
【００３１】多層膜を形成した後のポリイミド薄膜は仮
基板から容易に剥離ができたが、多層膜とポリイミド薄
膜との付着が十分でなく、ピンセットの先で擦ると多層
膜が一部剥げ落ち、実用には問題が残った。フッ素の含
有量が多いため多層膜とポリイミド薄膜との十分な付着
が得られなかったこと、さらに、ポリイミド薄膜の熱膨
張率が８×１０ー５／℃と大きく、多層膜の熱膨張率０
．４〜０．５×１０ー５／℃程度とは差が著しくなるた
め、両者の界面には剥離を促進させる応力が残留してい
ることが原因として考えられた。Although the polyimide thin film after forming the multilayer film could be easily peeled off from the temporary substrate, the adhesion between the multilayer film and the polyimide thin film was insufficient, and when rubbed with the tip of tweezers, a portion of the multilayer film peeled off. However, problems remained in practical use. Due to the high fluorine content, sufficient adhesion between the multilayer film and the polyimide thin film could not be obtained, and furthermore, the thermal expansion coefficient of the polyimide thin film was as large as 8 x 10-5/°C, and the multilayer film had a thermal expansion coefficient of 0.
．． Since the difference is significant from about 4 to 0.5 x 10-5/°C, it is thought that the cause is that stress that promotes peeling remains at the interface between the two.
【００３２】上述した誘電体多層膜フィルタを使用した
光学要素の実施例を以下に列挙する。Examples of optical elements using the above dielectric multilayer filter are listed below.
【００３３】図９（ａ），（ｂ）は本発明による光学要
素の第１の実施例としてフィルタ入り光ファイバを示す
図である。この図において（ａ）は平面図、（ｂ）は光
ファイバの光軸Ａ−Ａ’に沿う断面図である。この図中
符号２４，２５は光ファイバで、中央部２６の被覆部が
除去されている。２７は薄膜フィルタで、その基板部分
はポリイミドである。２８はフィルタ配設用の溝、２９
はファイバとフィルタを保持する基板である。このフィ
ルタ収納光ファイバの構造を得るための製造方法として
は、まず光ファイバ２４，２５を予め基板２９に設けた
溝に配設、固定し（この段階で光ファイバ２４，２５は
切断されていない）、接着剤で固定する。次に、光ファ
イバの光軸に垂直にもしくは傾いた直線Ｂ−Ｂ’に沿っ
て光ファイバのコア部を完全に切断するように溝２８を
形成する。次いで形成した溝２８内に、ポリイミド薄膜
を基板とする薄膜フィルタ２７を挿入し、光学用接着剤
で固定する。FIGS. 9(a) and 9(b) are diagrams showing a filtered optical fiber as a first embodiment of the optical element according to the present invention. In this figure, (a) is a plan view, and (b) is a cross-sectional view along the optical axis AA' of the optical fiber. Reference numerals 24 and 25 in this figure are optical fibers, and the covering portion of the central portion 26 has been removed. 27 is a thin film filter, the substrate portion of which is made of polyimide. 28 is a groove for arranging a filter, 29
is the substrate that holds the fiber and filter. As a manufacturing method for obtaining the structure of this filter-accommodating optical fiber, first, the optical fibers 24 and 25 are arranged and fixed in grooves previously provided on the substrate 29 (at this stage, the optical fibers 24 and 25 are not cut). ), fix with adhesive. Next, a groove 28 is formed so as to completely cut the core portion of the optical fiber along a straight line BB' perpendicular to or inclined to the optical axis of the optical fiber. Next, a thin film filter 27 having a polyimide thin film as a substrate is inserted into the formed groove 28 and fixed with an optical adhesive.
【００３４】図１０はこのフィルタ入り光ファイバの特
性を示すグラフであって、入力ファイバから白色光を導
入したときの出力ファイバ光を光スペクトルアナライザ
で分光したものである。ここで用いたポリイミド薄膜フ
ィルタは、前述した実験例１において得られた短波長通
過形のもので、図２の工程によって得られた厚さが約２
０μｍ、大きさ２ｍｍ角のものである。この大きさは図
２（ｃ）の工程において市販のダイシングソーで切れ目
を入れることによって得られたものである。また光ファ
イバには、コア径約１０μｍ、クラッド外径約１２５μ
ｍ、コアとクラッドの比屈折率差約０．３％のものを用
いた。図４の誘電体多層膜フィルタの特性と比べ、透過
域における損失が回折損失の分増加した。また、誘電体
多層膜フィルタは光ファイバの光軸垂直方向に対して８
度傾けて配設したため、図４の分光特性より短波長方向
に移動した。同じ工程により５０個のフィルタ入り光フ
ァイバを作製して透過損失を測定した結果、いずれのも
のも１．３μｍでは０．５ｄＢ以下、１．５５μｍでは
５５ｄＢ以上であった。この特性は、例えば、波長多重
ＯＴＤＲ（オプチカル・タイムドメイン・リフレクトメ
トリイ）を用いた光ファイバ伝送路の障害検出において
、ＯＴＤＲ光が受・発光素子に混入するのを防ぐフィル
タとしての実用性を有している（ Ｈ．Ｔａｋａｓｕｇ
ｉ ｅｔ．ａｌｌ．’Ｄｅｓｉｇｎ ａｎｄ Ｅｖａｌ
ｕａｔｉｏｎ ｏｆ Ａｕｔｍａｔｉｃ Ｏｐｔｉｃａ
ｌ Ｆｉｂｅｒ Ｏｐｅｒａｔｉｏｎ Ｓｕｐｐｏｒｔ
Ｓｙｓｔｅｍ’，Ｐｒｏｃｅｅｄｉｎｇｓ ｏｆ３９
ｔｈ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｗｉｒｅ ａｎｄ
Ｃａｂｌｅ Ｓｙｍｐｏｓｉｕｍ， １９９０，ｐｐ
．６３２）。さらに、これらは−２５〜７０℃の熱サイ
クル試験（４時間／サイクル）２００サイクルを経た後
にも特性の劣化がない安定な特性を示した。FIG. 10 is a graph showing the characteristics of this filtered optical fiber, in which the output fiber light is spectrally analyzed by an optical spectrum analyzer when white light is introduced from the input fiber. The polyimide thin film filter used here is the short wavelength-passing type obtained in Experimental Example 1 described above, and the thickness obtained by the process shown in FIG.
It is 0 μm in size and 2 mm square. This size was obtained by making cuts using a commercially available dicing saw in the process shown in FIG. 2(c). In addition, the optical fiber has a core diameter of approximately 10 μm and a cladding outer diameter of approximately 125 μm.
m, with a relative refractive index difference of about 0.3% between the core and the cladding. Compared to the characteristics of the dielectric multilayer filter shown in FIG. 4, the loss in the transmission region increased by the amount of diffraction loss. In addition, the dielectric multilayer filter has an angle of 8
Since it was arranged at an angle, it moved in the direction of shorter wavelengths than the spectral characteristics shown in FIG. Fifty filtered optical fibers were manufactured using the same process and the transmission loss was measured, and the transmission loss was 0.5 dB or less at 1.3 μm and 55 dB or more at 1.55 μm. This characteristic makes it practical as a filter that prevents OTDR light from entering receiving and emitting elements, for example, in detecting faults in optical fiber transmission lines using wavelength-multiplexed OTDR (optical time domain reflectometry). ( H. Takasug
i et. all. 'Design and Eval
vation of Automatic Optica
l Fiber Operation Support
System',Proceedings of39
th International Wire and
Cable Symposium, 1990, pp.
．． 632). Furthermore, these exhibited stable characteristics with no deterioration of characteristics even after 200 cycles of thermal cycle tests (4 hours/cycle) at -25 to 70°C.
【００３５】図１１は、本発明による光学要素の第２の
実施例を示すものであって、先の第１の実施例とは多芯
の光ファイバを用いる点が異なる。この図において符号
３０は多芯の光ファイバであって、Ｃ−Ｃ’の断面構造
で示すように、等しい間隔で並んだ光ファイバが被覆３
１により一本にコード化されたものである。多芯の光フ
ァイバとしては、例えば外径約１２５μｍのファイバを
２５０μｍ間隔で並べた２〜８芯程度のものを用いるこ
とができる（例えば、電子情報通信学会春季全国大会講
演論文集、Ｂ−６４９，Ｂ−６５４，Ｂ−６５５等）。
また図中符号３２は薄膜フィルタであって、その基板部
分はポリイミドである。符号３３は溝、３４はファイバ
とフィルタ薄片を保持する基板である。本実施例では、
第１の実施例と同じ工程で多数のフィルタ内蔵ファイバ
を得ることができ、一芯あたりのコストをさらに安価に
することができる。FIG. 11 shows a second embodiment of the optical element according to the present invention, which differs from the first embodiment in that a multi-core optical fiber is used. In this figure, reference numeral 30 denotes a multicore optical fiber, and as shown in the cross-sectional structure of C-C', optical fibers lined up at equal intervals are coated 3.
1 is coded into one line. As a multicore optical fiber, for example, about 2 to 8 fibers with an outer diameter of about 125 μm arranged at 250 μm intervals can be used (for example, IEICE Spring National Conference Proceedings, B-649). , B-654, B-655, etc.). Further, reference numeral 32 in the figure is a thin film filter, and its substrate portion is made of polyimide. Reference numeral 33 is a groove, and 34 is a substrate that holds the fiber and filter thin piece. In this example,
A large number of fibers with built-in filters can be obtained through the same process as in the first embodiment, and the cost per fiber can be further reduced.
【００３６】図１２は本発明による光学要素の第３の実
施例を示すもので、偏光子としての応用例を示している
。この図において符号３５は偏波面保持光ファイバ、３
６はポリイミド薄膜を基板とする偏光分離膜、３７は溝
、３８は基板である。ここで、溝３７はファイバ光軸に
対しては４５度程度傾斜し、基板面に対しては垂直に形
成する。また、偏波面保持光ファイバの主軸は基板面に
対して０度もしくは９０度となるように設定する。これ
によって、入射側ファイバを伝搬する偏光成分のうち基
板面に平行な偏光成分のみがその偏光方向を保ちながら
出力側ファイバより出力される。FIG. 12 shows a third embodiment of the optical element according to the present invention, and shows an example of its application as a polarizer. In this figure, reference numeral 35 denotes a polarization-maintaining optical fiber;
6 is a polarization separation film having a polyimide thin film as a substrate, 37 is a groove, and 38 is a substrate. Here, the groove 37 is formed at an angle of about 45 degrees with respect to the fiber optical axis and perpendicular to the substrate surface. Further, the main axis of the polarization maintaining optical fiber is set to be at 0 degrees or 90 degrees with respect to the substrate surface. As a result, among the polarized light components propagating through the input fiber, only the polarized light component parallel to the substrate surface is outputted from the output fiber while maintaining its polarization direction.
【００３７】図１３は本発明による光学要素の第４の実
施例を示すもので、符号３９、４０はフェルールを構成
するジルコニアセラミック製の嵌合部とステンレス製の
フランジ部、４１は光ファイバ、４２は基板部分がポリ
イミドのフィルタ、４３はフィルタ配設用の溝、４４は
接着剤である。この実施例では、ポリイミド薄膜を基板
とするフィルタ４２を、ファイバを成端するためのフェ
ルールの中に配設した構成になっている。このフェルー
ルにハウジング（図示せず）を施すことによって光コネ
クタ用のプラグが得られる。この実施例による構造は、
既存の標準的な部品の中にフィルタによる機能を付加で
きる利点がある。FIG. 13 shows a fourth embodiment of the optical element according to the present invention, in which reference numerals 39 and 40 indicate a zirconia ceramic fitting part and a stainless steel flange part constituting a ferrule, 41 an optical fiber, 42 is a filter whose substrate portion is made of polyimide, 43 is a groove for arranging the filter, and 44 is an adhesive. In this embodiment, a filter 42 having a polyimide thin film as a substrate is disposed within a ferrule for terminating a fiber. A plug for an optical connector is obtained by applying a housing (not shown) to this ferrule. The structure according to this example is
There is an advantage that filter functions can be added to existing standard parts.
【００３８】図１４は本発明による光学要素の第５の実
施例を示すもので、光コネクタ内の光ファイバ端面の突
合せ部分にポリイミド薄膜フィルタを挾んだものである
。この図において、符号４５は光ファイバ、４６は光フ
ァイバ端末を収容するフェルール、４７はポリイミド薄
膜を基板とするフィルタである。フェルール中心即ちフ
ァイバコア中心はスリーブ４８によって所要の精度で一
致している。突合せ部のフェルール端面は光軸に対して
垂直、斜めまたは球面状に研磨されている。この実施例
は、既存の標準的な部品の中にフィルタによる機能を付
加できる利点を有するとともに、溝形成が不要で特に簡
易な構成である。FIG. 14 shows a fifth embodiment of the optical element according to the present invention, in which a polyimide thin film filter is sandwiched between the abutting portions of the end faces of optical fibers in an optical connector. In this figure, reference numeral 45 is an optical fiber, 46 is a ferrule for accommodating the optical fiber terminal, and 47 is a filter having a polyimide thin film as a substrate. The center of the ferrule, ie, the center of the fiber core, is aligned with the required precision by the sleeve 48. The end face of the ferrule at the abutting portion is polished perpendicular to the optical axis, obliquely, or spherically. This embodiment has the advantage that a filter function can be added to an existing standard component, and also has a particularly simple structure since no groove formation is required.
【００３９】図１５は本発明による光学要素の第６の実
施例を示す図であって、ポリイミド薄膜を基板とする誘
電体多層膜フィルタを、光ファイバで形成した方向性結
合器（いわゆるファイバカップラ）の出力端に配設した
ものである。この図中符号４９，５０は入力側光ファイ
バ端子、５１，５２は出力側光ファイバ端子、５３は光
結合部、５４，５５はポリイミド薄膜を基板とするフィ
ルタ薄片、５６はフィルタを配設する溝、５７は光ファ
イバとフィルタを固定するための基板である。ここでは
、波長分離素子として用いたファイバカップラの波長分
離度を向上させる目的でポリイミド薄膜フィルタを用い
ている。また同じ構成で光の伝搬方向を逆にして使う場
合、即ち異なる２つの波長光を合波する場合にもポリイ
ミド薄膜フィルタを用いることができる。この場合のフ
ィルタは、ファイバカップラに入力する光のスペクトラ
ムの一部を削りとったり、反射によって光源方向に戻る
光のうち特定の波長成分を除去する目的で用いる。FIG. 15 is a diagram showing a sixth embodiment of the optical element according to the present invention, in which a dielectric multilayer filter with a polyimide thin film as a substrate is combined with a directional coupler (so-called fiber coupler) formed of an optical fiber. ) is installed at the output end of the In this figure, numerals 49 and 50 are input side optical fiber terminals, 51 and 52 are output side optical fiber terminals, 53 is an optical coupling part, 54 and 55 are filter thin pieces having a polyimide thin film as a substrate, and 56 is a filter. The groove 57 is a substrate for fixing the optical fiber and filter. Here, a polyimide thin film filter is used for the purpose of improving the wavelength separation degree of the fiber coupler used as a wavelength separation element. A polyimide thin film filter can also be used when the same configuration is used with the light propagation direction reversed, that is, when two different wavelength lights are combined. The filter in this case is used for the purpose of cutting off part of the spectrum of light input to the fiber coupler or removing a specific wavelength component from the light returning toward the light source by reflection.
【００４０】図１６は本発明による光学要素の第７の実
施例を示すもので、光ファイバ５８と受光器５９との間
にポリイミド薄膜フィルタ６０を配設した例である。符
号６１は受光器のガラス窓面であり、ポリイミド薄膜フ
ィルタはここに光学接着剤で固定されている。また符号
６２は半導体受光素子である。この場合、光ファイバ５
８と受光器５９が連結していないため光の結合が最大に
なるよう両者の光軸を合わせる必要がある。FIG. 16 shows a seventh embodiment of the optical element according to the present invention, in which a polyimide thin film filter 60 is disposed between an optical fiber 58 and a light receiver 59. Reference numeral 61 is a glass window surface of the light receiver, and a polyimide thin film filter is fixed thereto with an optical adhesive. Further, reference numeral 62 is a semiconductor light receiving element. In this case, the optical fiber 5
Since the light receiver 8 and the light receiver 59 are not connected, it is necessary to align their optical axes so that the coupling of light is maximized.
【００４１】図１７は本発明による光学要素の第８の実
施例を示す図であって、ポリイミド薄膜を基板とする誘
電体多層膜フィルタをガラス光導波路中に配設した構造
を示している。この図において符号６３は光導波路のコ
ア、６４は光導波路のクラッド、６５は光導波路形成用
の基板、６６はポリイミド薄膜を基板とするフィルタ、
６７は溝である。この光導波路の場合には、光導波路の
コアとクラッド部分は元々基板と一体の構造であるため
に、光ファイバを用いた場合と比べ、光ファイバを基板
に固定する工程を省略できる。また、第２の実施例の場
合のように多数本の光導波路を並列して形成し、一括し
てフィルタ薄片を配設する構造も勿論可能である。これ
らは光導波路にファイバを接続することによりピグテー
ル型のフィルタを構成できる。FIG. 17 is a diagram showing an eighth embodiment of the optical element according to the present invention, showing a structure in which a dielectric multilayer filter having a polyimide thin film as a substrate is disposed in a glass optical waveguide. In this figure, numeral 63 is the core of the optical waveguide, 64 is the cladding of the optical waveguide, 65 is a substrate for forming the optical waveguide, and 66 is a filter whose substrate is a polyimide thin film.
67 is a groove. In the case of this optical waveguide, since the core and cladding portion of the optical waveguide are originally integrated with the substrate, the step of fixing the optical fiber to the substrate can be omitted compared to the case where an optical fiber is used. Furthermore, as in the case of the second embodiment, a structure in which a large number of optical waveguides are formed in parallel and the filter thin pieces are disposed all at once is also possible. These can be configured into a pigtail type filter by connecting a fiber to an optical waveguide.
【００４２】図１８は本発明による光学要素の第９の実
施例を示す図であって、偏光子としての機能を得るため
のものである。この場合、ポリイミド薄膜を基板とする
偏光分離膜７０は、光導波路コア６８の光軸に対しては
約４５度、基板面（図示せず）に対しては垂直になるよ
うな溝７１の中に配設される。通常光導波路の場合には
偏波保持性を有し、かつ偏波主軸が基板と平行方向（Ｔ
Ｅ）と垂直方向（ＴＭ）を向いているため、第３の実施
例の場合のような偏波主軸の合わせが不要な点で有利で
ある。FIG. 18 is a diagram showing a ninth embodiment of an optical element according to the present invention, which is intended to function as a polarizer. In this case, the polarization separation film 70 with a polyimide thin film as a substrate is placed in a groove 71 that is approximately 45 degrees to the optical axis of the optical waveguide core 68 and perpendicular to the substrate surface (not shown). will be placed in In the case of a normal optical waveguide, it has polarization maintaining property and the main axis of polarization is parallel to the substrate (T
Since it is oriented perpendicular to E), it is advantageous in that it is not necessary to align the principal axis of polarization as in the case of the third embodiment.
【００４３】図１９は本発明による光学要素の第１０の
実施例を示す図であって、ポリイミド薄膜を基板とする
フィルタを、光導波路で形成した方向性結合器の出力端
もしくは入力端に配設するものである。この図中符号７
２，７３はフィルタ、７４，７５は光導波路のコア、７
６は光導波路のクラッド、７７は溝、７８は光結合部で
ある。これらのフィルタの役割は、上記第６の実施例と
同様である。FIG. 19 is a diagram showing a tenth embodiment of the optical element according to the present invention, in which a filter having a polyimide thin film as a substrate is arranged at the output end or input end of a directional coupler formed of an optical waveguide. It is to be established. Code 7 in this figure
2 and 73 are filters, 74 and 75 are optical waveguide cores, and 7
6 is a cladding of the optical waveguide, 77 is a groove, and 78 is an optical coupling portion. The roles of these filters are the same as in the sixth embodiment.
【００４４】図２０は本発明による光学要素の第１１の
実施例を示す図であって、ポリイミド薄膜を基板とする
フィルタの薄片を複数個配設したフィルタ入り光ファイ
バを示すものである。図中符号７９，８０はポリイミド
薄膜を基板とするフィルタ、８１，８２は光ファイバ、
８３，８４は溝、８５は基板である。この構成は、除去
したい波長成分に対する阻止域減衰量がフィルタ一個分
では不十分な場合に有効な方法である。この方法は、上
記の第１の実施例ないし第１０の実施例のすべてに適用
できる。FIG. 20 is a view showing an eleventh embodiment of the optical element according to the present invention, and shows a filter-containing optical fiber in which a plurality of filter thin pieces having a polyimide thin film as a substrate are arranged. In the figure, numerals 79 and 80 are filters having a polyimide thin film as a substrate, 81 and 82 are optical fibers,
83 and 84 are grooves, and 85 is a substrate. This configuration is an effective method when the stopband attenuation for a wavelength component to be removed is insufficient for one filter. This method can be applied to all of the first to tenth embodiments described above.
【００４５】[0045]
【発明の効果】以上説明したように、本発明によれば、
光ファイバもしくは光導波路中に誘電体多層膜フィルタ
を含む安価な部品を得ることができる。[Effects of the Invention] As explained above, according to the present invention,
An inexpensive component including a dielectric multilayer filter in an optical fiber or optical waveguide can be obtained.
【図１】本発明の誘電体多層膜フィルタを例示する断面
図である。FIG. 1 is a cross-sectional view illustrating a dielectric multilayer filter of the present invention.
【図２】本発明の誘電体多層膜フィルタの製造方法を工
程順に示す断面図である。FIG. 2 is a cross-sectional view showing the method for manufacturing a dielectric multilayer filter according to the present invention in order of steps.
【図３】本発明の誘電体多層膜フィルタの別な製造方法
を工程順に示す断面図である。FIG. 3 is a cross-sectional view illustrating another manufacturing method of the dielectric multilayer filter of the present invention in order of steps.
【図４】実験例で作製した誘電体多層膜フィルタの分光
特性を示すグラフである。FIG. 4 is a graph showing the spectral characteristics of a dielectric multilayer filter manufactured in an experimental example.
【図５】同じく長波長域通過形のフィルタの分光特性を
示すグラフである。FIG. 5 is a graph showing the spectral characteristics of a long wavelength pass type filter.
【図６】同じく狭帯域形のフィルタの分光特性を示すグ
ラフである。FIG. 6 is a graph showing the spectral characteristics of a similarly narrow band type filter.
【図７】実験例で作製したフィルタの厚さ分布の１例を
示すグラフ。FIG. 7 is a graph showing an example of the thickness distribution of a filter produced in an experimental example.
【図８】実験例で作製したフィルタの厚さ分布の他の例
を示すグラフ。FIG. 8 is a graph showing another example of the thickness distribution of the filter produced in the experimental example.
【図９】本発明による光学要素の第１の実施例を示す図
で、（ａ）はフィルタ入り光ファイバの平面図、（ｂ）
はＡ−Ａ’断面図である。FIG. 9 is a diagram showing a first embodiment of the optical element according to the present invention, (a) is a plan view of a filter-containing optical fiber, (b)
is a sectional view taken along line AA'.
【図１０】図１１に示すフィルタ入り光ファイバの分光
特性を例示するグラフである。10 is a graph illustrating the spectral characteristics of the filtered optical fiber shown in FIG. 11. FIG.
【図１１】本発明による光学要素の第２の実施例を示す
平面図である。FIG. 11 is a plan view of a second embodiment of the optical element according to the invention.
【図１２】本発明による光学要素の第３の実施例を示す
平面図である。FIG. 12 is a plan view of a third embodiment of the optical element according to the invention.
【図１３】本発明による光学要素の第４の実施例を示す
断面図である。FIG. 13 is a cross-sectional view of a fourth embodiment of an optical element according to the invention.
【図１４】本発明による光学要素の第５の実施例を示し
、（ａ）は一部断面図、（ｂ）はＤ−Ｄ’断面図である
。FIG. 14 shows a fifth embodiment of the optical element according to the present invention, in which (a) is a partial sectional view and (b) is a DD' sectional view.
【図１５】本発明による光学要素の第６の実施例を示す
平面図である。FIG. 15 is a plan view showing a sixth embodiment of the optical element according to the invention.
【図１６】本発明による光学要素の第７の実施例を示す
側面図である。FIG. 16 is a side view of a seventh embodiment of an optical element according to the invention.
【図１７】本発明による光学要素の第８の実施例を示し
、（ａ）は平面図、（ｂ）は側面図。FIG. 17 shows an eighth embodiment of the optical element according to the present invention, in which (a) is a plan view and (b) is a side view.
【図１８】本発明による光学要素の第９の実施例を示す
平面図である。FIG. 18 is a plan view showing a ninth embodiment of an optical element according to the invention.
【図１９】本発明による光学要素の第１０の実施例を示
す平面図である。FIG. 19 is a plan view showing a tenth embodiment of the optical element according to the invention.
【図２０】本発明による光学要素の第１１の実施例を示
す平面図である。FIG. 20 is a plan view showing an eleventh embodiment of an optical element according to the invention.
【図２１】従来の誘電体多層膜フィルタを用いた光学要
素の１つの例を示す図で、（ａ）は平面図、（ｂ）はＡ
−Ａ’断面図である。FIG. 21 is a diagram showing an example of an optical element using a conventional dielectric multilayer filter, in which (a) is a plan view and (b) is an A
-A' sectional view.
【図２２】従来の誘電体多層膜フィルタを用いた光学要
素の別の例を示す平面図である。FIG. 22 is a plan view showing another example of an optical element using a conventional dielectric multilayer filter.
【図２３】従来の誘電体多層膜の断面図である。FIG. 23 is a cross-sectional view of a conventional dielectric multilayer film.
【図２４】２種類の多層膜形成技術で作製されたフィル
タに生じる反りを比較するグラフである。FIG. 24 is a graph comparing warpage that occurs in filters manufactured using two types of multilayer film formation techniques.
【図２５】図２４に示すＡ，Ｂの各フィルタの特性を示
すグラフである。FIG. 25 is a graph showing characteristics of filters A and B shown in FIG. 24;
１，２，６，７，８，９，２４，２５，４１，４５，４
９，５０，５１，５２，５８，８１，８２ 光フ
ァイバ
３，１１，１２ 誘電体多層膜フィルタ薄片４，
１３，２８，３３，３７，４３，５６，６７，７１，７
７，８３，８４溝５，１４，２９，３４，３８，５７，
８５ 固定用基板１０，５３，７８ 方向
性結合器の光結合部１５ 誘電体多層膜フィルタ
のガラス基板部１６，２０ 誘電体多層膜
１７ 低屈折率誘電体層
１８ 高屈折率誘電体層
１９ ポリイミド薄膜
２１，２７，３２，３６，４２，４７，５４，５５，６
０，６６，７０，７２，７３，７９，８０ 誘電
体多層膜フィルタ
２２ 仮基板
２３ 切れ目
２６ 光ファイバの被覆除去部分３０ 多
芯光ファイバ
３１ 多芯光ファイバの被覆部
３５ 偏波保持ファイバ
３９ フェルール嵌合部
４０ フェルールフランジ部
４４ 接着剤
５９ 受光器
６１ ガラス窓面
６２ 半導体受光素子
６３，６８，７４，７５ 光導波路コア６４
光導波路クラッド1, 2, 6, 7, 8, 9, 24, 25, 41, 45, 4
9, 50, 51, 52, 58, 81, 82 Optical fiber 3, 11, 12 Dielectric multilayer filter thin piece 4,
13, 28, 33, 37, 43, 56, 67, 71, 7
7, 83, 84 groove 5, 14, 29, 34, 38, 57,
85 Fixing substrate 10, 53, 78 Optical coupling part 15 of directional coupler Glass substrate part 16, 20 of dielectric multilayer filter Dielectric multilayer film 17 Low refractive index dielectric layer 18 High refractive index dielectric layer 19 Polyimide Thin film 21, 27, 32, 36, 42, 47, 54, 55, 6
0, 66, 70, 72, 73, 79, 80 Dielectric multilayer filter 22 Temporary substrate 23 Cut 26 Optical fiber coating removed portion 30 Multicore optical fiber 31 Multicore optical fiber coating 35 Polarization maintaining fiber 39 Ferrule Fitting portion 40 Ferrule flange portion 44 Adhesive 59 Light receiver 61 Glass window surface 62 Semiconductor light receiving element 63, 68, 74, 75 Optical waveguide core 64
Optical waveguide cladding
Claims (8)
形成された屈折率の異なる誘電体を積層した誘電体多層
膜フィルタにおいて、基板部がフッ素化ポリイミド薄膜
であることを特徴とした誘電体多層膜フィルタ。1. A dielectric multilayer filter in which dielectrics having different refractive indexes formed by ion-assisted vapor deposition are laminated on a substrate, wherein the substrate portion is a fluorinated polyimide thin film. filter.
り小さい熱膨張性を有することを特徴とした請求項１記
載の誘電体多層膜フィルタ。2. The dielectric multilayer filter according to claim 1, wherein the fluorinated polyimide has a smaller thermal expansion than the multilayer film portion.
量が１０〜３０％である請求項１記載の誘電体多層膜フ
ィルタ。3. The dielectric multilayer filter according to claim 1, wherein the fluorine content of the fluorinated polyimide is 10 to 30%.
面が平滑な仮基板上に所要の厚さに塗布し、乾燥、硬化
させてフッ素化ポリイミド薄膜を形成する工程と、前記
フッ素化ポリイミド薄膜上に誘電体多層膜を形成する工
程と、前記誘電体多層膜とフッ素化ポリイミド薄膜とか
らなる光フィルタを前記仮基板から剥離する工程とを具
備した誘電体多層膜フィルタの製造方法。4. A step of applying a liquid fluorinated polyimide material to a desired thickness on a temporary substrate with a smooth surface, drying and curing to form a fluorinated polyimide thin film; A method for manufacturing a dielectric multilayer filter, comprising the steps of: forming a dielectric multilayer film; and peeling off an optical filter made of the dielectric multilayer film and a fluorinated polyimide thin film from the temporary substrate.
フッ素化ポリイミドの前駆体であるフッ素化ポリアミド
酸の溶液である請求項４記載の誘電体多層膜フィルタの
製造方法。5. The method for manufacturing a dielectric multilayer filter according to claim 4, wherein the liquid fluorinated polyimide material is a solution of fluorinated polyamic acid, which is a precursor of fluorinated polyimide.
可溶性フッ素化ポリイミドの溶液である請求項４記載の
誘電体多層膜フィルタの製造方法。6. The method for manufacturing a dielectric multilayer filter according to claim 4, wherein the liquid fluorinated polyimide material is a soluble fluorinated polyimide solution.
工程に、該光フィルタを切断する工程を含むことを特徴
とする請求項４記載の誘電体多層膜フィルタの製造方法
。7. The method for manufacturing a dielectric multilayer filter according to claim 4, wherein the step of peeling off the optical filter from the temporary substrate includes the step of cutting the optical filter.
素子と該間隙中に配設された光フィルタとを具備した光
学要素において、前記光フィルタがクレーム１の誘電体
多層膜フィルタであることを特徴とした光学要素。8. An optical element comprising an optical element having a minute gap formed in an optical path and an optical filter disposed in the gap, wherein the optical filter is a dielectric multilayer filter according to claim 1. An optical element characterized by
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3012277A JP2608633B2 (en) | 1990-02-13 | 1991-02-01 | Dielectric multilayer filter, method of manufacturing the same, and optical element using the same |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2-31766 | 1990-02-13 | ||
| JP3176690 | 1990-02-13 | ||
| JP3012277A JP2608633B2 (en) | 1990-02-13 | 1991-02-01 | Dielectric multilayer filter, method of manufacturing the same, and optical element using the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04211203A true JPH04211203A (en) | 1992-08-03 |
| JP2608633B2 JP2608633B2 (en) | 1997-05-07 |
Family
ID=26347856
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3012277A Expired - Lifetime JP2608633B2 (en) | 1990-02-13 | 1991-02-01 | Dielectric multilayer filter, method of manufacturing the same, and optical element using the same |
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| Country | Link |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006058473A (en) * | 2004-08-18 | 2006-03-02 | Oyokoden Lab Co Ltd | Dielectric multilayered film filter and its manufacturing method |
| WO2006073069A1 (en) * | 2005-01-06 | 2006-07-13 | Central Glass Company, Limited | Process for producing optical multilayer film filter and optical multilayer film filter |
| JP2008181121A (en) * | 2006-12-28 | 2008-08-07 | Nippon Shokubai Co Ltd | Light selective transmission filter |
| EP2075633A1 (en) * | 2007-12-28 | 2009-07-01 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO | Method of releasing a plate made of brittle material, assembly of a support and peeling arrangement, and peeling arrangement |
| WO2009084956A1 (en) * | 2007-12-28 | 2009-07-09 | Nederlandse Organisatie Voor Toegepast Natuurwetenschappelijk Onderzoek Tno | Method of releasing an adaptive optical plate, assembly of a support and peeling arrangement, and peeling arrangement |
| WO2022004496A1 (en) * | 2020-07-01 | 2022-01-06 | 富士フイルム株式会社 | Sensor and band-pass filter |
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| JP2006215212A (en) | 2005-02-02 | 2006-08-17 | Omron Corp | Optical multiplexer/demultiplexer and method of manufacturing the same |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5111158A (en) * | 1974-07-19 | 1976-01-29 | Komao Oeda | DENRYUSEIGENKI |
| JPS5193237A (en) * | 1975-02-14 | 1976-08-16 | ||
| JPS5565239A (en) * | 1978-11-10 | 1980-05-16 | Nippon Kogaku Kk <Nikon> | Method of forming film of titanium oxide on plastic base plate |
| JPS60262102A (en) * | 1984-06-09 | 1985-12-25 | Horiba Ltd | Chip type multi-layered interference filter and its production |
| JPS6360401A (en) * | 1986-09-01 | 1988-03-16 | Fujitsu Ltd | Manufacture of optical film parts |
| JPS6364003A (en) * | 1986-09-05 | 1988-03-22 | Teijin Ltd | Optical filter |
| JPS6388505A (en) * | 1986-10-02 | 1988-04-19 | Teijin Ltd | Production of optical filter |
| JPS63116106A (en) * | 1986-11-05 | 1988-05-20 | Matsushita Electric Ind Co Ltd | Optical multi-layer film and its manufacture |
| JPH01182324A (en) * | 1988-01-14 | 1989-07-20 | Nippon Telegr & Teleph Corp <Ntt> | Fluorine-containing polyimide and production thereof |
| JPH01217037A (en) * | 1988-02-26 | 1989-08-30 | Chisso Corp | Production of silicon-containing polyimide having low moisture absorption and high adhesiveness and precursor thereof |
| JPH01261422A (en) * | 1988-04-13 | 1989-10-18 | Central Glass Co Ltd | Fluorinated aromatic polyamide and polyimide |
-
1991
- 1991-02-01 JP JP3012277A patent/JP2608633B2/en not_active Expired - Lifetime
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5111158A (en) * | 1974-07-19 | 1976-01-29 | Komao Oeda | DENRYUSEIGENKI |
| JPS5193237A (en) * | 1975-02-14 | 1976-08-16 | ||
| JPS5565239A (en) * | 1978-11-10 | 1980-05-16 | Nippon Kogaku Kk <Nikon> | Method of forming film of titanium oxide on plastic base plate |
| JPS60262102A (en) * | 1984-06-09 | 1985-12-25 | Horiba Ltd | Chip type multi-layered interference filter and its production |
| JPS6360401A (en) * | 1986-09-01 | 1988-03-16 | Fujitsu Ltd | Manufacture of optical film parts |
| JPS6364003A (en) * | 1986-09-05 | 1988-03-22 | Teijin Ltd | Optical filter |
| JPS6388505A (en) * | 1986-10-02 | 1988-04-19 | Teijin Ltd | Production of optical filter |
| JPS63116106A (en) * | 1986-11-05 | 1988-05-20 | Matsushita Electric Ind Co Ltd | Optical multi-layer film and its manufacture |
| JPH01182324A (en) * | 1988-01-14 | 1989-07-20 | Nippon Telegr & Teleph Corp <Ntt> | Fluorine-containing polyimide and production thereof |
| JPH01217037A (en) * | 1988-02-26 | 1989-08-30 | Chisso Corp | Production of silicon-containing polyimide having low moisture absorption and high adhesiveness and precursor thereof |
| JPH01261422A (en) * | 1988-04-13 | 1989-10-18 | Central Glass Co Ltd | Fluorinated aromatic polyamide and polyimide |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006058473A (en) * | 2004-08-18 | 2006-03-02 | Oyokoden Lab Co Ltd | Dielectric multilayered film filter and its manufacturing method |
| WO2006073069A1 (en) * | 2005-01-06 | 2006-07-13 | Central Glass Company, Limited | Process for producing optical multilayer film filter and optical multilayer film filter |
| JP2006189596A (en) * | 2005-01-06 | 2006-07-20 | Central Glass Co Ltd | Method of manufacturing optical multilayer filter, and optical multi-layer filter |
| JP2008181121A (en) * | 2006-12-28 | 2008-08-07 | Nippon Shokubai Co Ltd | Light selective transmission filter |
| EP2075633A1 (en) * | 2007-12-28 | 2009-07-01 | Nederlandse Organisatie voor toegepast- natuurwetenschappelijk onderzoek TNO | Method of releasing a plate made of brittle material, assembly of a support and peeling arrangement, and peeling arrangement |
| WO2009084955A1 (en) * | 2007-12-28 | 2009-07-09 | Nederlandse Organisatie Voor Toegepast Natuurwetenschappelijk Onderzoek Tno | Method of releasing a plate made of brittle material, assembly of a support and peeling arrangement, and peeling arrangement |
| WO2009084956A1 (en) * | 2007-12-28 | 2009-07-09 | Nederlandse Organisatie Voor Toegepast Natuurwetenschappelijk Onderzoek Tno | Method of releasing an adaptive optical plate, assembly of a support and peeling arrangement, and peeling arrangement |
| WO2022004496A1 (en) * | 2020-07-01 | 2022-01-06 | 富士フイルム株式会社 | Sensor and band-pass filter |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2608633B2 (en) | 1997-05-07 |
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