JPH05275911A - Antenna container - Google Patents

Antenna container

Info

Publication number
JPH05275911A
JPH05275911A JP6633092A JP6633092A JPH05275911A JP H05275911 A JPH05275911 A JP H05275911A JP 6633092 A JP6633092 A JP 6633092A JP 6633092 A JP6633092 A JP 6633092A JP H05275911 A JPH05275911 A JP H05275911A
Authority
JP
Japan
Prior art keywords
container
antenna
heat insulating
refractive index
insulating material
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP6633092A
Other languages
Japanese (ja)
Inventor
Osamu Ishii
修 石井
Yoshihiro Kimachi
良弘 木町
Keiichiro Ito
圭一郎 伊藤
Kenichi Kagoshima
憲一 鹿子嶋
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP6633092A priority Critical patent/JPH05275911A/en
Publication of JPH05275911A publication Critical patent/JPH05275911A/en
Pending legal-status Critical Current

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Abstract

PURPOSE:To provide an antenna container which can improve the antenna directivity and also can miniaturize an antenna. CONSTITUTION:A heat insulator 3 contains the dielectric layers having the low and high refractive indexes to a far infrared ray which are alternately laminated on an insulator substrate 11. Then the insulator 3 is embedded into or stuck to a structure part formed in the direction where the radio waves are intensively radiated from a superconductive antenna element 9 of the outer container of a duplex container 1. Meanwhile a heat insulator 5 consisting of a metallic thin film is embedded into or stuck to a structure part formed in the direction where no radio wave is radiated respectively.

Description

【発明の詳細な説明】Detailed Description of the Invention

【産業上の利用分野】本発明は超伝導材料を用いたアン
テナ素子を収容する冷凍容器に関し、特に、アンテナの
指向性の向上を図ることが可能で、かつ小形化し得るア
ンテナ容器に係る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating container for housing an antenna element made of a superconducting material, and more particularly to an antenna container capable of improving the directivity of the antenna and being miniaturized.

【従来の技術】超伝導材料は低損失であるため種々の電
子部品への応用が期待されている。超伝導材料の応用分
野の一つとして、小形アンテナが挙げられる。金属を用
いて作製した放射素子では小形化に伴い導体損失が増し
アンテナの放射効率が低下するが、素子を超伝導化する
ことで小形化しても導体損失が少なく放射効率の高いア
ンテナを実現することができる。超伝導部品を機能させ
るためには、超伝導転移温度以下の低温に安定に保持す
る必要がある。従って、超伝導アンテナのみの小形化だ
けではなく、その収納容器や冷凍機の小形、軽量化も重
要である。一般に、冷凍容器の断熱材としては金属箔等
が用いられているが、アンテナの収納容器として用いる
ためには電波が透過する必要があるので、金属製の断熱
材は不適当である。屈折率差の大きい誘電体層を積層し
た構造は、光の反射層として知られており、この反射波
長が遠赤外線領域にあれば断熱材としても十分機能する
ことが、例えば、特願平３−２９５９４２号によって開
示されている。一方、アンテナにおいては一般に電波を
送受信したい方向のみに指向性があることが重要であ
る。アンテナに指向性を付与する１方法として、反射板
を用いる方法が知られている。これは、金属等の良導体
から成る平面あるいは曲面状の反射鏡をアンテナ近傍に
設置することで、電波を反射し反射鏡と反対の方向の利
得を高める方法である。2. Description of the Related Art Since superconducting materials have low loss, they are expected to be applied to various electronic parts. One of the fields of application of superconducting materials is small antennas. A radiating element made of metal will increase the conductor loss and reduce the radiation efficiency of the antenna with miniaturization, but by making the element superconducting, even if miniaturized, a conductor loss will be small and radiation efficiency will be high. be able to. In order for a superconducting component to function, it must be stably maintained at a temperature below the superconducting transition temperature. Therefore, it is important not only to downsize the superconducting antenna alone, but also to reduce the size and weight of the storage container and refrigerator. Generally, a metal foil or the like is used as a heat insulating material for a freezing container, but a metal heat insulating material is not suitable because it needs to transmit radio waves in order to be used as a container for an antenna. A structure in which dielectric layers having a large difference in refractive index are laminated is known as a light reflection layer, and if the reflection wavelength is in the far infrared region, it can sufficiently function as a heat insulating material. -295942. On the other hand, it is generally important for an antenna to have directivity only in the direction in which radio waves are desired to be transmitted and received. A method using a reflector is known as one method of giving directivity to an antenna. This is a method in which a flat or curved reflecting mirror made of a good conductor such as metal is installed in the vicinity of the antenna to reflect radio waves and increase the gain in the direction opposite to the reflecting mirror.

【発明が解決しようとする課題】上述のようにアンテナ
素子に超伝導材料を用いたアンテナでは、アンテナ素子
を冷凍容器に収納して使用するが、従来良好な断熱性
と、所望のアンテナの指向性を得ることが両立し、か
つ、これらを小形で、経済的に実現し得るものがなかっ
た。本発明は、このような従来の問題点に鑑み、超伝導
体を用いたアンテナを実現する際に、所望の方向にのみ
電波を透過し、かつ、超伝導部品を超伝導転移温度以下
の低温に効率良く保持することのできる冷却容器を提供
することを目的としている。In the antenna using the superconducting material for the antenna element as described above, the antenna element is housed in a freezing container for use, but conventionally, it has good heat insulation and desired antenna orientation. It was not possible to achieve both of these characteristics, and to realize them economically. In view of such conventional problems, the present invention transmits a radio wave only in a desired direction and realizes a superconducting component at a low temperature below a superconducting transition temperature when an antenna using a superconductor is realized. It is an object of the present invention to provide a cooling container that can be efficiently retained.

【課題を解決するための手段】本発明は上記問題点を解
決するため成されたものであって、超伝導アンテナ素子
を収納する第１の容器と、該第１の容器を収納する第２
の容器を備え、第１の容器と第２の容器との間に冷却剤
を充填して用いるアンテナ容器であって、上記第２の容
器の超伝導アンテナ素子から電波が強く放出される方向
の構造部には、絶縁体基板上に遠赤外線に対する屈折率
が低い誘電材料の層と屈折率が高い誘電材料の層を交互
に積層して成る誘電体多層膜からなる断熱材を、また、
電波が放出されない方向の構造部には、金属薄膜によっ
て成る断熱材を埋設または、貼設したアンテナ容器であ
る。The present invention has been made to solve the above-mentioned problems, and it is a first container for accommodating a superconducting antenna element and a second container for accommodating the first container.
An antenna container which is provided with a container of (1) and is filled with a coolant between the first container and the second container and used in a direction in which radio waves are strongly emitted from the superconducting antenna element of the second container. In the structure part, a heat insulating material composed of a dielectric multilayer film in which layers of a dielectric material having a low refractive index for far infrared rays and layers of a dielectric material having a high refractive index are alternately laminated on an insulating substrate,
An antenna container in which a heat insulating material made of a metal thin film is embedded or attached to a structure portion in a direction in which radio waves are not emitted.

【作用】本発明による冷凍容器は、電波を強く放出する
方向には、高屈折率の誘電体材料と、低屈折率を有する
誘電体材料を交互に多層膜状に形成した赤外線反射膜
を、２重デュワーの中間部に配置することにより、熱線
の反射率を高めて輻射による熱流入を低減せしめ、しか
も電波はほとんど損失無く透過する一方、電波が放射さ
れる必要の無い方向については金属薄膜の断熱層を設
け、これを電波に対して反射鏡として作用させることを
特徴としている。The refrigerating container according to the present invention has an infrared reflection film in which a dielectric material having a high refractive index and a dielectric material having a low refractive index are alternately formed in a multilayer film form in a direction in which radio waves are strongly emitted, By arranging it in the middle part of the double dewar, the reflectance of heat rays is increased to reduce the heat inflow due to radiation, and the radio waves are transmitted with almost no loss, while the metal thin film is used in the direction where the radio waves need not be radiated. It is characterized in that a heat insulating layer is provided, and this acts as a reflecting mirror for radio waves.

【実施例】図１および図２は本発明の一実施例を示す図
であって、図１は側面の断面図を、図２は上面図を示し
ている。これらの図において、１はＦＲＰ製の２重デュ
ワー、２は液体窒素、３は誘電体多層膜構成の断熱材、
４は真空引き用バルブ、５は金属製断熱材、６はＦＲＰ
製アンテナ容器、７は排気およびヘリウム置換用バル
ブ、８は給電線、９はダイポールアンテナ、１０は温度
検出用の熱電対、１１は絶縁体基板、１２は高誘電率
層、１３は低誘電率層、１４は基板、１５は金属薄膜を
表わしている。ダイポールアンテナ９は直径２ｍｍ、長
さ９７．７８ｍｍの銅製アンテナであり、中央で給電し
ている。共振周波数は１．５ＧＨｚである。本実施例で
は反射板の影響のみを考慮しているので、アンテナ構成
材料として超伝導体は用いていない。アンテナはアンテ
ナ容器６に収められ、この容器を液体窒素に浸すことで
７７Ｋまで冷却する。この際、アンテナ容器内は水分の
凍結を避けるために真空に排気後、熱伝導を良好に保つ
ためにヘリウムを封入している。反射板を兼ねる断熱材
５はポリエチレンシート上に５０ミクロン厚のアルミニ
ウム箔を付着したものを１０層積層した平板であり、ア
ンテナ素子から１／４波長（５２．３ｍｍ）離れた場所
に設置した。断熱材５の金属被膜を堆積させる基板材料
には熱伝導率の低い有機物等の材料の方が、伝導による
熱の出入りを少なくできるので適している。比較のため
に、このアンテナ容器と同一構造で反射板部分を誘電体
多層膜からなる断熱材３で置き換えた容器も検討した。
断熱材３の断面構造は図３に示す。同図において、２１
は高屈折率を有する薄膜層（以下、高屈折率層とも言
う）で、本実施例ではスパッタ法を用いて形成した厚さ
約１．０３ミクロンのＡｓ40Ｓ60層である。２２は低屈
折率を有する薄膜層（以下、低屈折率層とも言う）で、
本実施例ではスパッタ法を用いて形成した厚さ約１．７
４ミクロンの６５ｍｏｌ％ＺｒＦ4 −３５ｍｏｌ％Ｂａ
Ｆ2 層である。２３は高表面精度を有するガラス基板
（厚み１ｍｍ）であり、高屈折率層と低屈折率層は交互
に１０層ずつ積層されている。各層へ入射する光線はそ
れぞれの層の界面で反射されるが、高屈折率層から低屈
折率層へと入射する場合には入射光と反射光は同位相な
のに対し、低屈折率層から高屈折率層へと入射する場合
には反射光は入射光と逆位相になる。各誘電体層の光学
的厚さ（Ｄ＝ｎｄ ｎ：屈折率、ｄ：層の物理的厚み）
を、１／４波長と設定することで、波長４Ｄの光線が各
層界面から反射した光は同位相となり、全体として反射
効率が最も高まる。本実施例では、室温付近での黒体幅
射に最も寄与する波長１０ミクロン程度の赤外線に対す
る反射率が最も大きくなるように、各層の厚みを設定し
た。すなわち、Ａｓ40Ｓ60の屈折率は２．４３、６５ｍ
ｏｌ％ＺｒＦ4 −３５ｍｏｌ％ＢａＦ2 の屈折率は１．
４４なので、光学厚さが１／４波長に相当する物理厚さ
はそれぞれ１．０３ミクロンおよび１．７１ミクロンと
算出される。ガラス、Ａｓ40Ｓ60、６５ｍｏｌ％ＺｒＦ
4 −３５ｍｏｌ％ＢａＦ2 のいずれもが絶縁体であるた
め、電波は損失無く透過する。図４に、反射板が無い場
合、また、図５に、反射板が在る場合のアンテナのＹ−
Ｚ，Ｘ−Ｚ面内における指向性パターンを示す。指向性
強度は放射強度が最大の場合を１として規格化してい
る。反射板を設けることで、アンテナ前面（＋Ｘ方向）
への放射パターンが鋭くなり、指向性が増すことが分
る。また、両容器について液体窒素貯留試験を行なっ
た。液体窒素を容器に満たした状態から、自然蒸発して
容器内部温度が室温まで復帰するのに必要な時間は、金
属反射板を併用した容器では約８５時間、誘電体多層膜
のみを用いた容器では約７２時間である。誘電体多層膜
の光吸収率は波長が６〜７ミクロン以下の範囲では１０
％以下と小さいが、この波長以上の赤外線は吸収率が増
して断熱特性が劣化するのに対し、アルミニウム箔は波
長の増加と共に反射率が増し、波長１０ミクロンの赤外
線に対し反射率９８％と優れた断熱特性が得られるた
め、上記の液体窒素貯留試験の差となって現われたもの
と考えられる。この様に、誘電体多層膜からなる断熱材
と反射板を兼用する金属板からなる断熱材を併用するこ
とは断熱特性の改善にも有益である。また、反射板を真
空中に保持するので、反射板の腐食やゴミの付着等も防
止できる利点もある。本実施例では金属反射板は平板の
みを用いたが、曲面状の金属板も実施例と同様、熱の流
入を防ぎ、且つ電波を反射するために使用できることは
明らかである。また、この実施例では高屈折率層、低屈
折率層としてその他の誘電材料、例えば高屈折率層とし
てＣｅＯ2 ，ＺｒＯ2 などの酸化物や、Ｇｅ，Ｓｉなど
の半導体、ＺｎＳ，ＡｓＳ，ＧｅＳなどの硫化物、Ｐｂ
Ｆ2 ，ＣｅＦ3 などの佛化物など、低屈折率層としてＢ
ａＦ2 ，ＭｇＦ2 ，ＡｌＦ3 ，ＣａＦ2 ，ＬｉＦ，Ｚｒ
Ｆ4 などの佛化物、ＭｇＯなどの酸化物を用いて構成し
た誘電体多層膜を赤外線反射層として用いても同様の効
果が得られる。特に、硫化物や佛化物は一般に酸化物よ
りも長波長の赤外線に対する吸収が少ないので断熱材と
して適している。なお、上記実施例では、断熱材を第２
の容器の中間真空部に設ける例について述べているが、
これは真空中に限るものではなく、断熱材を容器の壁体
中に埋設し、あるいは貼設したものであっても良いこと
は明らかである。1 and 2 are views showing an embodiment of the present invention, in which FIG. 1 is a side sectional view and FIG. 2 is a top view. In these figures, 1 is a double dewar made of FRP, 2 is liquid nitrogen, 3 is a heat insulating material having a dielectric multilayer film structure,
4 is a vacuuming valve, 5 is a metal heat insulating material, and 6 is FRP
Antenna container made by 7, valve for exhaust and helium replacement, 8 feed line, 9 dipole antenna, 10 thermocouple for temperature detection, 11 insulating substrate, 12 high dielectric constant layer, 13 low dielectric constant A layer, 14 is a substrate, and 15 is a metal thin film. The dipole antenna 9 is a copper antenna having a diameter of 2 mm and a length of 97.78 mm, and is fed at the center. The resonance frequency is 1.5 GHz. In this embodiment, since only the influence of the reflector is taken into consideration, the superconductor is not used as the antenna constituent material. The antenna is housed in the antenna container 6 and cooled to 77K by immersing the container in liquid nitrogen. At this time, the antenna container is evacuated to a vacuum in order to avoid freezing of water, and then helium is sealed in order to keep good heat conduction. The heat insulating material 5, which also serves as a reflector, is a flat plate formed by laminating 10 layers of a 50-micron-thick aluminum foil adhered on a polyethylene sheet, and was installed at a place separated from the antenna element by a quarter wavelength (52.3 mm). A material such as an organic material having a low thermal conductivity is more suitable for the substrate material on which the metal coating of the heat insulating material 5 is deposited, since the heat input and output can be reduced. For comparison, a container having the same structure as this antenna container and having a reflector plate portion replaced with a heat insulating material 3 made of a dielectric multilayer film was also examined.
The cross-sectional structure of the heat insulating material 3 is shown in FIG. In the figure, 21
Is a thin film layer having a high refractive index (hereinafter, also referred to as a high refractive index layer), which is an As 40 S 60 layer having a thickness of about 1.03 μm formed by the sputtering method in this embodiment. 22 is a thin film layer having a low refractive index (hereinafter, also referred to as a low refractive index layer),
In the present embodiment, the thickness formed by the sputtering method is about 1.7.
4 micron 65 mol% ZrF 4 -35 mol% Ba
It is the F 2 layer. Reference numeral 23 denotes a glass substrate (thickness: 1 mm) having high surface accuracy, in which 10 high refractive index layers and 10 low refractive index layers are alternately laminated. Light rays incident on each layer are reflected at the interface of each layer, but when incident from the high refractive index layer to the low refractive index layer, the incident light and the reflected light are in phase, whereas When incident on the refractive index layer, the reflected light has a phase opposite to that of the incident light. Optical thickness of each dielectric layer (D = nd n: refractive index, d: physical thickness of layer)
Is set to 1/4 wavelength, the light reflected by the interface of each layer of the light beam of wavelength 4D has the same phase, and the reflection efficiency is maximized as a whole. In this example, the thickness of each layer was set so that the reflectance for infrared rays having a wavelength of about 10 microns, which contributes most to the black body radiation near room temperature, was maximized. That is, the refractive index of As 40 S 60 is 2.43, 65m
The refractive index of ol% ZrF 4 -35 mol% BaF 2 is 1.
Since it is 44, the physical thicknesses corresponding to an optical thickness of ¼ wavelength are calculated to be 1.03 micron and 1.71 micron, respectively. Glass, As 40 S 60 , 65 mol% ZrF
Since all of 4-35 mol% BaF 2 are insulators, radio waves are transmitted without loss. In FIG. 4, there is no reflector, and in FIG. 5, the antenna Y-
The directivity pattern in a Z, X-Z plane is shown. The directional intensity is standardized with 1 when the radiant intensity is maximum. By installing a reflector, the antenna front surface (+ X direction)
It can be seen that the radiation pattern to the point becomes sharper and the directivity increases. Further, a liquid nitrogen storage test was conducted on both containers. The time required for the internal temperature of the container to return to room temperature by spontaneously evaporating from the state where the container is filled with liquid nitrogen is about 85 hours for the container that also uses the metal reflector, and the container using only the dielectric multilayer film. It takes about 72 hours. The light absorption rate of the dielectric multilayer film is 10 in the wavelength range of 6 to 7 microns or less.
Although it is as small as 10% or less, infrared rays with wavelengths longer than this wavelength have increased absorptivity and deteriorated heat insulation properties, whereas aluminum foil has increased reflectance with increase in wavelength and has a reflectance of 98% for infrared rays with a wavelength of 10 microns. It is considered that this was due to the difference in the above liquid nitrogen storage test because excellent heat insulating properties were obtained. Thus, the combined use of the heat insulating material made of a dielectric multilayer film and the heat insulating material made of a metal plate that also serves as a reflector is useful for improving heat insulating properties. Further, since the reflecting plate is held in vacuum, there is an advantage that it is possible to prevent corrosion of the reflecting plate and adhesion of dust. In this embodiment, only a flat metal plate was used as the metal reflection plate, but it is obvious that a curved metal plate can be used to prevent heat from flowing in and reflect radio waves as in the case of this embodiment. In this embodiment, other high dielectric layers and low dielectric layers are made of other dielectric materials, for example, oxides such as CeO 2 and ZrO 2 as high refractive index layers, semiconductors such as Ge and Si, ZnS, AsS and GeS. Sulfides such as Pb
B as a low-refractive-index layer, such as a compound such as F 2 or CeF 3.
aF 2 , MgF 2 , AlF 3 , CaF 2 , LiF, Zr
Similar effects can be obtained by using a dielectric multilayer film made of a compound such as F 4 or an oxide such as MgO as an infrared reflective layer. In particular, sulfides and phosphides are generally suitable as a heat insulating material because they absorb less infrared rays having a longer wavelength than oxides. In the above embodiment, the heat insulating material is the second
Although an example of installing in the intermediate vacuum part of the container of
This is not limited to the vacuum, and it is obvious that the heat insulating material may be embedded or attached in the wall of the container.

【発明の効果】以上述べた通り、本発明のアンテナ容器
は、超伝導アンテナ用冷却槽であって、佛化物、硫化物
などの誘電体多層膜で形成した断熱材および金属薄膜か
らなる断熱材を、２重デュワーの中間部分に挿入するこ
とで冷却槽の断熱効果を向上させており、この金属薄膜
を電波に対する反射板として用いてアンテナの指向性を
向上させる構成を採っているので、超伝導材料を用いた
アンテナ素子を収容する冷凍容器を小形かつ経済的に実
現することができる利点がある。As described above, the antenna container of the present invention is a cooling tank for a superconducting antenna, which is a heat insulating material formed of a dielectric multi-layered film such as halide or sulfide, and a heat insulating material composed of a metal thin film. Is inserted in the middle part of the double dewar to improve the heat insulation effect of the cooling tank, and this metal thin film is used as a reflector for radio waves to improve the directivity of the antenna. There is an advantage that it is possible to realize a small-sized and economical refrigeration container that houses an antenna element using a conductive material.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明の一実施例の側面の断面図である。FIG. 1 is a side sectional view of an embodiment of the present invention.

【図２】本発明の一実施例の上面図である。FIG. 2 is a top view of an embodiment of the present invention.

【図３】断熱材の断面構造の例を示す図である。FIG. 3 is a diagram showing an example of a cross-sectional structure of a heat insulating material.

【図４】反射板が無い場合のアンテナの指向性パターン
を示す図である。FIG. 4 is a diagram showing a directivity pattern of an antenna when there is no reflector.

【図５】反射板が在る場合のアンテナの指向性パターン
を示す図である。FIG. 5 is a diagram showing a directivity pattern of an antenna when a reflector is present.

【符号の説明】[Explanation of symbols]

１ ２重デュワー ２ 液体窒素 ３ 誘電体多層膜構成の断熱材 ４ 真空引き用バルブ ５ 金属薄膜からなる断熱材 ６ アンテナ容器 ７ 排気およびヘリウム置換 ８ 給電線 ９ ダイポールアンテナ １０ 温度検出用熱電対 １１ 絶縁体基板 １２ 高誘電率層 １３ 低誘電率層 １４ 基板 １５ 金属薄膜 ２１ 高屈折率層 ２２ 低屈折率層 ２３ ガラス基板 1 Double Dewar 2 Liquid Nitrogen 3 Insulation Material of Dielectric Multilayer Film 4 Vacuum Evacuation Valve 5 Heat Insulation Material Made of Metallic Thin Film 6 Antenna Container 7 Exhaust and Helium Replacement 8 Feed Line 9 Dipole Antenna 10 Thermocouple for Temperature Detection 11 Insulation Body substrate 12 High dielectric constant layer 13 Low dielectric constant layer 14 Substrate 15 Metal thin film 21 High refractive index layer 22 Low refractive index layer 23 Glass substrate

─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───

【手続補正書】[Procedure amendment]

【提出日】平成４年３月２５日[Submission date] March 25, 1992

【手続補正１】[Procedure Amendment 1]

【補正対象書類名】明細書[Document name to be amended] Statement

【補正対象項目名】発明の詳細な説明[Name of item to be amended] Detailed explanation of the invention

【補正方法】変更[Correction method] Change

【補正内容】[Correction content]

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は超伝導材料を用いたアン
テナ素子を収容する冷凍容器に関し、特に、アンテナの
指向性の向上を図ることが可能で、かつ小形化し得るア
ンテナ容器に係る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating container for housing an antenna element made of a superconducting material, and more particularly to an antenna container capable of improving the directivity of the antenna and being miniaturized.

【０００２】[0002]

【従来の技術】超伝導材料は低損失であるため種々の電
子部品への応用が期待されている。超伝導材料の応用分
野の一つとして、小形アンテナが挙げられる。金属を用
いて作製した放射素子では小形化に伴い導体損失が増し
アンテナの放射効率が低下するが、素子を超伝導化する
ことで小形化しても導体損失が少なく放射効率の高いア
ンテナを実現することができる。2. Description of the Related Art Since superconducting materials have low loss, they are expected to be applied to various electronic parts. One of the fields of application of superconducting materials is small antennas. A radiating element made of metal will increase the conductor loss and reduce the radiation efficiency of the antenna with miniaturization, but by making the element superconducting, even if miniaturized, a conductor loss will be small and radiation efficiency will be high. be able to.

【０００３】超伝導部品を機能させるためには、超伝導
転移温度以下の低温に安定に保持する必要がある。従っ
て、超伝導アンテナのみの小形化だけではなく、その収
納容器や冷凍機の小形、軽量化も重要である。一般に、
冷凍容器の断熱材としては金属箔等が用いられている
が、アンテナの収納容器として用いるためには電波が透
過する必要があるので、金属製の断熱材は不適当であ
る。In order for a superconducting component to function, it is necessary to stably maintain it at a temperature below the superconducting transition temperature. Therefore, it is important not only to downsize the superconducting antenna alone, but also to reduce the size and weight of the storage container and refrigerator. In general,
Although a metal foil or the like is used as a heat insulating material for a freezing container, a metal heat insulating material is unsuitable because it needs to transmit radio waves in order to be used as a container for an antenna.

【０００４】屈折率差の大きい誘電体層を積層した構造
は、光の反射層として知られており、この反射波長が遠
赤外線領域にあれば断熱材としても十分機能すること
が、例えば、特願平３−２９５９４２号によって開示さ
れている。A structure in which dielectric layers having a large difference in refractive index are laminated is known as a light reflection layer, and if the reflection wavelength is in the far infrared region, it can sufficiently function as a heat insulating material. It is disclosed by Japanese Patent Application No. 3-295942.

【０００５】一方、アンテナにおいては一般に電波を送
受信したい方向のみに指向性があることが重要である。
アンテナに指向性を付与する１方法として、反射板を用
いる方法が知られている。これは、金属等の良導体から
成る平面あるいは曲面状の反射鏡をアンテナ近傍に設置
することで、電波を反射し反射鏡と反対の方向の利得を
高める方法である。On the other hand, it is generally important for an antenna to have directivity only in the direction in which it is desired to send and receive radio waves.
A method using a reflector is known as one method of giving directivity to an antenna. This is a method in which a flat or curved reflecting mirror made of a good conductor such as metal is installed in the vicinity of the antenna to reflect radio waves and increase the gain in the direction opposite to the reflecting mirror.

【０００６】[0006]

【発明が解決しようとする課題】上述のようにアンテナ
素子に超伝導材料を用いたアンテナでは、アンテナ素子
を冷凍容器に収納して使用するが、従来良好な断熱性
と、所望のアンテナの指向性を得ることが両立し、か
つ、これらを小形で、経済的に実現し得るものがなかっ
た。In the antenna using the superconducting material for the antenna element as described above, the antenna element is housed in a freezing container for use, but conventionally, it has good heat insulation and desired antenna orientation. It was not possible to achieve both of these characteristics, and to realize them economically.

【０００７】本発明は、このような従来の問題点に鑑
み、超伝導体を用いたアンテナを実現する際に、所望の
方向にのみ電波を透過し、かつ、超伝導部品を超伝導転
移温度以下の低温に効率良く保持することのできる冷却
容器を提供することを目的としている。In view of the above conventional problems, the present invention transmits an electric wave only in a desired direction and realizes a superconducting component with a superconducting transition temperature when an antenna using a superconductor is realized. It is an object of the present invention to provide a cooling container capable of efficiently maintaining the following low temperatures.

【０００８】[0008]

【課題を解決するための手段】本発明は上記問題点を解
決するため成されたものであって、超伝導アンテナ素子
を収納する第１の容器と、該第１の容器を収納する第２
の容器を備え、第１の容器と第２の容器との間に冷却剤
を充填して用いるアンテナ容器であって、上記第２の容
器の超伝導アンテナ素子から電波が強く放出される方向
の構造部には、絶縁体基板上に遠赤外線に対する屈折率
が低い誘電材料の層と屈折率が高い誘電材料の層を交互
に積層して成る誘電体多層膜からなる断熱材を、また、
電波が放出されない方向の構造部には、金属薄膜によっ
て成る断熱材を埋設または、貼設したアンテナ容器であ
る。The present invention has been made to solve the above-mentioned problems, and it is a first container for accommodating a superconducting antenna element and a second container for accommodating the first container.
An antenna container which is provided with a container of (1) and is filled with a coolant between the first container and the second container and used in a direction in which radio waves are strongly emitted from the superconducting antenna element of the second container. In the structure part, a heat insulating material composed of a dielectric multilayer film in which layers of a dielectric material having a low refractive index for far infrared rays and layers of a dielectric material having a high refractive index are alternately laminated on an insulating substrate,
An antenna container in which a heat insulating material made of a metal thin film is embedded or attached to a structure portion in a direction in which radio waves are not emitted.

【０００９】[0009]

【作用】本発明による冷凍容器は、電波を強く放出する
方向には、高屈折率の誘電体材料と、低屈折率を有する
誘電体材料を交互に多層膜状に形成した赤外線反射膜
を、２重デュワーの中間部に配置することにより、熱線
の反射率を高めて輻射による熱流入を低減せしめ、しか
も電波はほとんど損失無く透過する一方、電波が放射さ
れる必要の無い方向については金属薄膜の断熱層を設
け、これを電波に対して反射鏡として作用させることを
特徴としている。The refrigerating container according to the present invention has an infrared reflection film in which a dielectric material having a high refractive index and a dielectric material having a low refractive index are alternately formed in a multilayer film form in a direction in which radio waves are strongly emitted, By arranging it in the middle part of the double dewar, the reflectance of heat rays is increased to reduce the heat inflow due to radiation, and the radio waves are transmitted with almost no loss, while the metal thin film is used in the direction where the radio waves need not be radiated. It is characterized in that a heat insulating layer is provided, and this acts as a reflecting mirror for radio waves.

【００１０】[0010]

【実施例】図１および図２は本発明の一実施例を示す図
であって、図１は側面の断面図を、図２は上面図を示し
ている。これらの図において、１はＦＲＰ製の２重デュ
ワー、２は液体窒素、３は誘電体多層膜構成の断熱材、
４は真空引き用バルブ、５は金属製断熱材、６はＦＲＰ
製アンテナ容器、７は排気およびヘリウム置換用バル
ブ、８は給電線、９はダイポールアンテナ、１０は温度
検出用の熱電対、１１は絶縁体基板、１２は高誘電率
層、１３は低誘電率層、１４は基板、１５は金属薄膜を
表わしている。1 and 2 are views showing an embodiment of the present invention, in which FIG. 1 is a side sectional view and FIG. 2 is a top view. In these figures, 1 is a double dewar made of FRP, 2 is liquid nitrogen, 3 is a heat insulating material having a dielectric multilayer film structure,
4 is a vacuuming valve, 5 is a metal heat insulating material, and 6 is FRP
Antenna container made by 7, valve for exhaust and helium replacement, 8 feed line, 9 dipole antenna, 10 thermocouple for temperature detection, 11 insulating substrate, 12 high dielectric constant layer, 13 low dielectric constant A layer, 14 is a substrate, and 15 is a metal thin film.

【００１１】ダイポールアンテナ９は直径２ｍｍ、長さ
９７．７８ｍｍの銅製アンテナであり、中央で給電して
いる。共振周波数は１．５ＧＨｚである。本実施例では
反射板の影響のみを考慮しているので、アンテナ構成材
料として超伝導体は用いていない。The dipole antenna 9 is a copper antenna having a diameter of 2 mm and a length of 97.78 mm and is fed at the center. The resonance frequency is 1.5 GHz. In this embodiment, since only the influence of the reflector is taken into consideration, the superconductor is not used as the antenna constituent material.

【００１２】アンテナはアンテナ容器６に収められ、こ
の容器を液体窒素に浸すことで７７Ｋまで冷却する。こ
の際、アンテナ容器内は水分の凍結を避けるために真空
に排気後、熱伝導を良好に保つためにヘリウムを封入し
ている。The antenna is housed in the antenna container 6 and cooled to 77K by immersing the container in liquid nitrogen. At this time, the antenna container is evacuated to a vacuum in order to avoid freezing of water, and then helium is sealed in order to keep good heat conduction.

【００１３】反射板を兼ねる断熱材５はポリエチレンシ
ート上に５０ミクロン厚のアルミニウム箔を付着したも
のを１０層積層した平板であり、アンテナ素子から１／
４波長（５２．３ｍｍ）離れた場所に設置した。断熱材
５の金属被膜を堆積させる基板材料には熱伝導率の低い
有機物等の材料の方が、伝導による熱の出入りを少なく
できるので適している。The heat insulating material 5, which also serves as a reflector, is a flat plate formed by laminating 10 layers of a 50 μm thick aluminum foil adhered on a polyethylene sheet.
It was installed at a location separated by 4 wavelengths (52.3 mm). A material such as an organic material having a low thermal conductivity is more suitable for the substrate material on which the metal coating of the heat insulating material 5 is deposited, since the heat input and output can be reduced.

【００１４】比較のために、このアンテナ容器と同一構
造で反射板部分を誘電体多層膜からなる断熱材３で置き
換えた容器も検討した。断熱材３の断面構造は図３に示
す。同図において、２１は高屈折率を有する薄膜層（以
下、高屈折率層とも言う）で、本実施例ではスパッタ法
を用いて形成した厚さ約１．０３ミクロンのＡｓ40Ｓ60
層である。２２は低屈折率を有する薄膜層（以下、低屈
折率層とも言う）で、本実施例ではスパッタ法を用いて
形成した厚さ約１．７４ミクロンの６５ｍｏｌ％ＺｒＦ
4 −３５ｍｏｌ％ＢａＦ2 層である。For comparison, a container having the same structure as this antenna container but having a reflector plate replaced with a heat insulating material 3 made of a dielectric multilayer film was also examined. The cross-sectional structure of the heat insulating material 3 is shown in FIG. In the figure, reference numeral 21 denotes a thin film layer having a high refractive index (hereinafter, also referred to as a high refractive index layer), and in this embodiment, As 40 S 60 having a thickness of about 1.03 μm formed by the sputtering method.
It is a layer. Reference numeral 22 denotes a thin film layer having a low refractive index (hereinafter, also referred to as a low refractive index layer), and in this embodiment, a thickness of about 1.74 μm and a thickness of 65 mol% ZrF.
4 is a -35mol% BaF 2 layer.

【００１５】２３は高表面精度を有するガラス基板（厚
み１ｍｍ）であり、高屈折率層と低屈折率層は交互に１
０層ずつ積層されている。各層へ入射する光線はそれぞ
れの層の界面で反射されるが、高屈折率層から低屈折率
層へと入射する場合には入射光と反射光は同位相なのに
対し、低屈折率層から高屈折率層へと入射する場合には
反射光は入射光と逆位相になる。Reference numeral 23 is a glass substrate (thickness: 1 mm) having a high surface precision, and the high refractive index layer and the low refractive index layer are alternately 1
0 layers are laminated. Light rays incident on each layer are reflected at the interface of each layer, but when incident from the high refractive index layer to the low refractive index layer, the incident light and the reflected light are in phase, whereas When incident on the refractive index layer, the reflected light has a phase opposite to that of the incident light.

【００１６】各誘電体層の光学的厚さ（Ｄ＝ｎｄ ｎ：
屈折率、ｄ：層の物理的厚み）を、１／４波長と設定す
ることで、波長４Ｄの光線が各層界面から反射した光は
同位相となり、全体として反射効率が最も高まる。本実
施例では、室温付近での黒体幅射に最も寄与する波長１
０ミクロン程度の赤外線に対する反射率が最も大きくな
るように、各層の厚みを設定した。Optical thickness of each dielectric layer (D = nd n:
By setting the refractive index, d: the physical thickness of the layer) to ¼ wavelength, the light of the wavelength 4D reflected from each layer interface has the same phase, and the reflection efficiency is maximized as a whole. In the present embodiment, the wavelength 1 that most contributes to the black body radiation near room temperature
The thickness of each layer was set so that the reflectance for infrared rays of about 0 micron was maximized.

【００１７】すなわち、Ａｓ40Ｓ60の屈折率は２．４
３、６５ｍｏｌ％ＺｒＦ4 −３５ｍｏｌ％ＢａＦ2 の屈
折率は１．４４なので、光学厚さが１／４波長に相当す
る物理厚さはそれぞれ１．０３ミクロンおよび１．７１
ミクロンと算出される。ガラス、Ａｓ40Ｓ60、６５ｍｏ
ｌ％ＺｒＦ4 −３５ｍｏｌ％ＢａＦ2 のいずれもが絶縁
体であるため、電波は損失無く透過する。That is, the refractive index of As 40 S 60 is 2.4.
Since the refractive index of 3,65 mol% ZrF 4 -35 mol% BaF 2 is 1.44, the physical thickness corresponding to the quarter wavelength is 1.03 μm and 1.71 respectively.
Calculated as micron. Glass, As 40 S 60 , 65mo
Since all of 1% ZrF 4 and 35 mol% BaF 2 are insulators, radio waves are transmitted without loss.

【００１８】図４に、反射板が無い場合、また、図５
に、反射板が在る場合のアンテナのＹ−Ｚ，Ｘ−Ｚ面内
における指向性パターンを示す。指向性強度は放射強度
が最大の場合を１として規格化している。反射板を設け
ることで、アンテナ前面（＋Ｘ方向）への放射パターン
が鋭くなり、指向性が増すことが分る。FIG. 4 shows the case without a reflector, and FIG.
FIG. 3 shows the directivity pattern in the YZ and XZ planes of the antenna when there is a reflector. The directional intensity is standardized with 1 when the radiant intensity is maximum. It can be seen that by providing the reflector, the radiation pattern toward the front surface of the antenna (+ X direction) becomes sharp and the directivity increases.

【００１９】また、両容器について液体窒素貯留試験を
行なった。液体窒素を容器に満たした状態から、自然蒸
発して容器内部温度が室温まで復帰するのに必要な時間
は、金属反射板を併用した容器では約８５時間、誘電体
多層膜のみを用いた容器では約７２時間である。Further, a liquid nitrogen storage test was conducted on both containers. The time required for the internal temperature of the container to return to room temperature by spontaneously evaporating from the state where the container is filled with liquid nitrogen is about 85 hours for the container that also uses the metal reflector, and the container using only the dielectric multilayer film. It takes about 72 hours.

【００２０】誘電体多層膜の光吸収率は波長が６〜７ミ
クロン以下の範囲では１０％以下と小さいが、この波長
以上の赤外線は吸収率が増して断熱特性が劣化するのに
対し、アルミニウム箔は波長の増加と共に反射率が増
し、波長１０ミクロンの赤外線に対し反射率９８％と優
れた断熱特性が得られるため、上記の液体窒素貯留試験
の差となって現われたものと考えられる。The light absorption rate of the dielectric multilayer film is as small as 10% or less in the wavelength range of 6 to 7 microns or less, but infrared rays of this wavelength or more increase the absorption rate and deteriorate the heat insulating property. It is considered that the foil has a higher reflectance as the wavelength increases, and an excellent heat insulating property with a reflectance of 98% with respect to infrared rays having a wavelength of 10 microns is obtained, which is a difference between the liquid nitrogen storage tests.

【００２１】この様に、誘電体多層膜からなる断熱材と
反射板を兼用する金属板からなる断熱材を併用すること
は断熱特性の改善にも有益である。また、反射板を真空
中に保持するので、反射板の腐食やゴミの付着等も防止
できる利点もある。As described above, the combined use of the heat insulating material made of a dielectric multilayer film and the heat insulating material made of a metal plate which also serves as a reflector is useful for improving heat insulating properties. Further, since the reflecting plate is held in vacuum, there is an advantage that it is possible to prevent corrosion of the reflecting plate and adhesion of dust.

【００２２】本実施例では金属反射板は平板のみを用い
たが、曲面状の金属板も実施例と同様、熱の流入を防
ぎ、且つ電波を反射するために使用できることは明らか
である。In the present embodiment, only the flat plate was used as the metal reflection plate, but it is clear that a curved metal plate can be used to prevent heat from flowing in and reflect radio waves as in the case of the embodiment.

【００２３】また、この実施例では高屈折率層、低屈折
率層としてその他の誘電材料、例えば高屈折率層として
ＣｅＯ2 ，ＺｒＯ2 などの酸化物や、Ｇｅ，Ｓｉなどの
半導体、ＺｎＳ，ＡｓＳ，ＧｅＳなどの硫化物、ＰｂＦ
2 ，ＣｅＦ3 などの佛化物など、低屈折率層としてＢａ
Ｆ2 ，ＭｇＦ2 ，ＡｌＦ3 ，ＣａＦ2 ，ＬｉＦ，ＺｒＦ
4 などの佛化物、ＭｇＯなどの酸化物を用いて構成した
誘電体多層膜を赤外線反射層として用いても同様の効果
が得られる。特に、硫化物や佛化物は一般に酸化物より
も長波長の赤外線に対する吸収が少ないので断熱材とし
て適している。In this embodiment, other dielectric materials are used as the high refractive index layer and the low refractive index layer, for example, oxides such as CeO 2 and ZrO 2 as the high refractive index layer, semiconductors such as Ge and Si, ZnS, Sulfides such as AsS and GeS, PbF
2 , as a low-refractive-index layer such as CeF 3 and other compounds
F 2 , MgF 2 , AlF 3 , CaF 2 , LiF, ZrF
The same effect can be obtained by using a dielectric multilayer film composed of a halide such as 4 or an oxide such as MgO as an infrared reflecting layer. In particular, sulfides and carbides are generally suitable as heat insulating materials because they absorb less infrared rays having a longer wavelength than oxides.

【００２４】なお、上記実施例では、断熱材を第２の容
器の中間真空部に設ける例について述べているが、これ
は真空中に限るものではなく、断熱材を容器の壁体中に
埋設し、あるいは貼設したものであっても良いことは明
らかである。In the above embodiment, the heat insulating material is provided in the intermediate vacuum portion of the second container. However, this is not limited to the vacuum, and the heat insulating material is embedded in the wall of the container. However, it is clear that it may be attached or attached.

【００２５】[0025]

【発明の効果】以上述べた通り、本発明のアンテナ容器
は、超伝導アンテナ用冷却槽であって、佛化物、硫化物
などの誘電体多層膜で形成した断熱材および金属薄膜か
らなる断熱材を、２重デュワーの中間部分に挿入するこ
とで冷却槽の断熱効果を向上させており、この金属薄膜
を電波に対する反射板として用いてアンテナの指向性を
向上させる構成を採っているので、超伝導材料を用いた
アンテナ素子を収容する冷凍容器を小形かつ経済的に実
現することができる利点がある。As described above, the antenna container of the present invention is a cooling tank for a superconducting antenna, which is a heat insulating material formed of a dielectric multi-layered film such as a halide or sulfide and a heat insulating material composed of a metal thin film. Is inserted in the middle part of the double dewar to improve the heat insulation effect of the cooling tank, and this metal thin film is used as a reflector for radio waves to improve the directivity of the antenna. There is an advantage that it is possible to realize a small-sized and economical refrigeration container that houses an antenna element using a conductive material.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 鹿子嶋 憲一 東京都千代田区内幸町一丁目１番６号 日 本電信電話株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenichi Kagoshima 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 超伝導アンテナ素子を収納する第１の容
器と、該第１の容器を収納する第２の容器を備え、第１
の容器と第２の容器との間に冷却剤を充填して用いるア
ンテナ容器であって、 上記第２の容器の超伝導アンテナ素子から電波が強く放
出される方向の構造部には、絶縁体基板上に遠赤外線に
対する屈折率が低い誘電材料の層と屈折率が高い誘電材
料の層を交互に積層して成る誘電体多層膜からなる断熱
材を、 また、電波が放出されない方向の構造部には、金属薄膜
によって成る断熱材を埋設または、貼設したことを特徴
とするアンテナ容器。1. A first container for accommodating the superconducting antenna element, and a second container for accommodating the first container, the first container comprising:
An antenna container used by filling a coolant between the container and the second container, wherein an insulator is provided in a structure portion of the second container in a direction in which radio waves are strongly emitted from the superconducting antenna element. A heat insulating material composed of a dielectric multilayer film in which layers of a dielectric material having a low refractive index for far infrared rays and layers of a dielectric material having a high refractive index are alternately laminated on a substrate, and a structure part in a direction in which radio waves are not emitted The antenna container is characterized in that a heat insulating material made of a metal thin film is embedded or attached to the inside.
JP6633092A 1992-03-24 1992-03-24 Antenna container Pending JPH05275911A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6633092A JPH05275911A (en) 1992-03-24 1992-03-24 Antenna container

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6633092A JPH05275911A (en) 1992-03-24 1992-03-24 Antenna container

Publications (1)

Publication Number Publication Date
JPH05275911A true JPH05275911A (en) 1993-10-22

Family

ID=13312731

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6633092A Pending JPH05275911A (en) 1992-03-24 1992-03-24 Antenna container

Country Status (1)

Country Link
JP (1) JPH05275911A (en)

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