JPS61189431A - Appreciating method for non-reflecting film - Google Patents

Appreciating method for non-reflecting film

Info

Publication number
JPS61189431A
JPS61189431A JP60029279A JP2927985A JPS61189431A JP S61189431 A JPS61189431 A JP S61189431A JP 60029279 A JP60029279 A JP 60029279A JP 2927985 A JP2927985 A JP 2927985A JP S61189431 A JPS61189431 A JP S61189431A
Authority
JP
Japan
Prior art keywords
transmission band
transmittance
film
transmission characteristics
wavelength side
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
JP60029279A
Other languages
Japanese (ja)
Inventor
Mikio Hotta
堀田　幹生
Satoshi Kusaka
日下　敏
Hideki Noda
秀樹 野田
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP60029279A priority Critical patent/JPS61189431A/en
Publication of JPS61189431A publication Critical patent/JPS61189431A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for

Landscapes

  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Testing Of Optical Devices Or Fibers (AREA)
  • Surface Treatment Of Optical Elements (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

PURPOSE:To appreciate highly accurately the transmitting characteristics of a non-reflecting film by appreciating the minimum value of a transmissivity appearing on the short wavelength side from a designed transmission band. CONSTITUTION:A fixed regular relation shown in the graph is formed between the drop of transmissivity in the transmission band and the minimum value of the transmissivity appearing on the short wavelength side. Thereby, the characteristics of the non-reflecting film can be appreciated highly accurately by appreciating the minimum value of transmissivity appearing on the short wavelength side from the transmission band.

Description

【発明の詳細な説明】 〔１既　　要〕 無反射膜の透過特性の評価は、透過率測定の精度の限界
付近において行なわれるため困難が伴なうが、設計透過
帯より短波長側にあらわれる透過率の極小値を評価する
ことによって無反射膜の透過特性を高精度に評価するこ
とが可能である。[Detailed Description of the Invention] [1 Required] Evaluation of the transmission characteristics of a non-reflective film is difficult because it is performed near the limit of accuracy of transmittance measurement, but it is difficult to evaluate the transmission characteristics of a non-reflection film. By evaluating the minimum value of transmittance, it is possible to evaluate the transmission characteristics of a non-reflective film with high precision.

〔産業上の利用分野〕[Industrial application field]

本発明は無反射膜の評価方法、特に透過特性の評価を精
度良く行なう方法に係る。The present invention relates to a method for evaluating a non-reflective film, and particularly to a method for accurately evaluating transmission characteristics.

無反射膜あるいは反射防止膜は光学系において広く利用
されている。Non-reflective films or anti-reflective films are widely used in optical systems.

〔従来の技術〕[Conventional technology]

第３図に無反射膜の例を示すが、ガラス基体１上に順に
ＴｉＯ□膜２．ＳｉＯ□膜３．ＴｉＯ２膜４および５ｉ
Ｏｔ膜５が形成されている。。ＴｉＯ２はガラスより屈
折率が太き（、Ｓｉｎｇは小さい。このような無反射膜
の透過特性１としては９９％、さらには９９．５％以上
であることが要求されることは屡々である。An example of a non-reflective film is shown in FIG. 3, in which a TiO□ film 2. SiO□ film 3. TiO2 films 4 and 5i
An Ot film 5 is formed. . TiO2 has a higher refractive index (and Sing is smaller) than glass.The transmission characteristic 1 of such a non-reflective film is often required to be 99% or even 99.5% or more.

ところで、無圧、射膜の透過特性を評価する場合、第４
図に示す如（、光源１０からの光を光ファイバ１１を介
して被測定対象（この場合、無反射膜をコーティングし
たガラス）１２に当て、これを透過した光を光ファイバ
１３を介してセンサ１４で受けてパワーメータ１５で光
強度を測定し記録する。光透過率を求めるには、光ファ
イバ１１゜１３の間に被測定対象１２を置かずに測定し
た光強度を１００として、被測定対象１２を光ファイバ
１１．１３の間に置いた場合の光強度と比較することに
よって求めることができる。光源１０はモノクロメータ
を通すことにより波長可変であり、連続の波長帯域で透
過率を測定することができる。By the way, when evaluating the transmission characteristics of a no-pressure spray film, the fourth
As shown in the figure, light from a light source 10 is applied to an object to be measured (in this case, glass coated with a non-reflective film) 12 through an optical fiber 11, and the light transmitted through this is sent to a sensor through an optical fiber 13. 14, and measure and record the light intensity with a power meter 15. To determine the light transmittance, the light intensity measured without the object to be measured 12 placed between the optical fibers 11 and 13 is set as 100, and the light intensity is measured and recorded with the power meter 15. It can be determined by comparing the light intensity when the object 12 is placed between the optical fibers 11 and 13.The light source 10 is wavelength tunable by passing it through a monochromator, and the transmittance is measured in a continuous wavelength band. can do.

しかしながら、このような光透過率の測定方法では上記
のように９９％以上、あるいは９９．５％以上の透過特
性が満たされているかどうかを評価するためには、測定
精度が必ずしも高（ないという問題があった。特に、透
過特性は無反射膜の膜厚の精度に依存するが、上記のよ
うに高い透過特性を実現するような膜厚の制御は必ずし
も容易ではないので、透過特性を高精度で評価し、所望
の透過特性を満足しているか否か評価する必要がある。However, with this method of measuring light transmittance, the measurement accuracy is not necessarily high (or not) in order to evaluate whether the above-mentioned transmission characteristics of 99% or more or 99.5% or more are satisfied. In particular, the transmission characteristics depend on the accuracy of the thickness of the non-reflective film, and it is not always easy to control the film thickness to achieve high transmission characteristics as described above. It is necessary to evaluate the accuracy and whether or not the desired transmission characteristics are satisfied.

〔問題点を解決するための手段〕[Means for solving problems]

本発明者は、無反射膜の透過帯における透過特性は、透
過帯より短波長側に存在する透過率の極小値の変化に増
幅された形であられれることを見い出した。第１図に示
すように、無反射膜の透過特性は、透過帯の短波長側に
極値を有する曲線となる。そこで、本発明は、上記の如
き問題点を解決するために、所望の透過帯より短波長側
にあらわれる透過率の極小値により透過帯における透過
特性を評価する。The present inventor has discovered that the transmission characteristics of a non-reflection film in the transmission band are amplified by changes in the minimum value of transmittance that exists on the shorter wavelength side than the transmission band. As shown in FIG. 1, the transmission characteristics of the non-reflection film form a curve having an extreme value on the short wavelength side of the transmission band. Therefore, in order to solve the above problems, the present invention evaluates the transmission characteristics in the transmission band based on the minimum value of the transmittance that appears on the shorter wavelength side than the desired transmission band.

〔作　用〕[For production]

つまり、無反射膜の透過帯における透過特性が短波長側
では増幅された形となるため、極小値の透過率を評価す
ることによって、高精度に透過帯における透過特性を評
価することが可能になる。In other words, the transmission characteristics of the non-reflection film in the transmission band are amplified on the short wavelength side, so by evaluating the minimum value of transmittance, it is possible to evaluate the transmission characteristics in the transmission band with high accuracy. Become.

〔実施例〕　　　゛ 再び第３図を参照して説明する。ガラス、ＴｔＯｚ＋Ｓ
ｉＯ□の屈折率はそれぞれ１．’５１．　２．３．　１
．４６であり、無反射膜はガラスより屈折率が大−小一
大一小の膜で構成されている。[Example] ゛This will be explained with reference to FIG. 3 again. Glass, TtOz+S
The refractive index of iO□ is 1. '51. 2.3. 1
．． 46, and the antireflection film is composed of a film whose refractive index is larger than that of glass.

これらの膜２〜５はガラス基板（ＢＫ−７，厚さ０．５
〜１ｍｍ）１の表面を研磨および洗浄した後、イオンブ
レーティング法で連続的に堆積して形成することができ
る。しかし、イオンブレーティング法を用いても、膜厚
が薄い場合には膜厚の精度が必ずしも充分でない場合が
あり、無反射膜特性を劣化させる原因になっている。These films 2 to 5 are formed on a glass substrate (BK-7, thickness 0.5
After polishing and cleaning the surface of ~1 mm) 1, it can be formed by continuous deposition using an ion blasting method. However, even if the ion blating method is used, if the film thickness is small, the accuracy of the film thickness may not always be sufficient, which causes deterioration of the non-reflective film characteristics.

第１図に、上記の如き設計および作製法で得られた無反
射膜の透過特性を示す。曲線ａ　（実線）は最良の無反
射膜、曲線ｂ（破線）１曲線ｃ　（一点鎖線）および曲
線ｄ（二点鎖線）は透過率特性が劣化した無反射膜であ
る。最良の膜（ａ）とその他の膜（ｂ、ｃ、ｄ　）の間
には透過帯透過率の差は最大で２％しかないが、短波長
側に最初にあらわれる透過率極小値の差は１４％である
。透過率測定の分解能および誤差の点から２％程度の差
を正確に検出するのは難しいが、１４％程度の検出は容
易である。FIG. 1 shows the transmission characteristics of a non-reflective film obtained by the above-described design and manufacturing method. Curve a (solid line) is the best non-reflective film, curve b (dashed line), curve c (dash-dot line) and curve d (double-dashed line) are non-reflective films with deteriorated transmittance characteristics. The maximum difference in transmission band transmittance between the best film (a) and the other films (b, c, d) is only 2%, but the difference in the minimum transmittance value that first appears on the short wavelength side is It is 14%. Although it is difficult to accurately detect a difference of about 2% due to the resolution and error of transmittance measurement, it is easy to detect a difference of about 14%.

第２図は、透過帯における透過率の低下と短波長側にあ
らわれる透過率極小値との関係をあられしたものであり
、これら２つの量の間に一定の規則的関係があることが
わかる。従って、透過帯より短波長側にあらわれる透過
率極小値を評価することによって、無反射膜の透過帯の
特性を精度良く評価することができる。FIG. 2 shows the relationship between the decrease in transmittance in the transmission band and the minimum value of transmittance appearing on the short wavelength side, and it can be seen that there is a certain regular relationship between these two quantities. Therefore, by evaluating the transmittance minimum value that appears on the shorter wavelength side than the transmission band, it is possible to accurately evaluate the characteristics of the transmission band of the non-reflection film.

第２図において、無反射膜の透過率の許容範囲を９９．
５〜１００％の間とすると、これに対応する透過率極小
値の範囲は６７．５％　＋４．０％すなわ−３，５％ ちその幅は７．５％であり、特性評価の精度が向上する
ことがわかる。In FIG. 2, the permissible range of transmittance of the non-reflective film is 99.
If it is between 5% and 100%, the corresponding minimum transmittance range is 67.5% +4.0%, or -3.5%, and the width is 7.5%, which increases the accuracy of the characteristic evaluation. It can be seen that the results are improved.

〔発明の効果〕〔Effect of the invention〕

本発明により、無反射膜の透過帯における透過特性を精
度良く評価することが可能になる。According to the present invention, it is possible to accurately evaluate the transmission characteristics of a non-reflection film in the transmission band.

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

第１図は無反射膜の透過特性を表わすグラフ図、第２図
は透過帯における透過特性と短波長側極小透過率値との
関係を表わすグラフ図、第３図は無反射膜の断面図、第
４図は透過率測定方法を説明する図である。 ａ・・・最良の透過特性、 ｂ、　ｃ、　ｄ・・・劣化した透過特性、１・・・ガラ
ス、 ２．４・・・ＴｉＯ□膜、 ３．５・・・５ｉＯｚ膜。Figure 1 is a graph showing the transmission characteristics of the non-reflection film, Figure 2 is a graph showing the relationship between the transmission characteristics in the transmission band and the minimum transmittance value on the short wavelength side, and Figure 3 is a cross-sectional view of the non-reflection film. , FIG. 4 is a diagram for explaining the transmittance measurement method. a...Best transmission characteristics, b, c, d...Deteriorated transmission characteristics, 1...Glass, 2.4...TiO□ film, 3.5...5iOz film.

Claims (1)

【特許請求の範囲】[Claims] １、透明硬質基体表面に形成した無反射膜の設計波長を
中心とする透過帯における透過特性を評価するに当って
、該透過帯より短波長側の該透過帯に最も近い波長にあ
らわれる透過率の極小値により、透過帯における透過特
性を評価する無反射膜の評価方法。1. When evaluating the transmission characteristics of a non-reflective film formed on the surface of a transparent hard substrate in a transmission band centered around the design wavelength, the transmittance that appears at the wavelength closest to the transmission band on the shorter wavelength side of the transmission band An evaluation method for non-reflective films that evaluates the transmission characteristics in the transmission band based on the minimum value of .
JP60029279A 1985-02-19 1985-02-19 Appreciating method for non-reflecting film Pending JPS61189431A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP60029279A JPS61189431A (en) 1985-02-19 1985-02-19 Appreciating method for non-reflecting film

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP60029279A JPS61189431A (en) 1985-02-19 1985-02-19 Appreciating method for non-reflecting film

Publications (1)

Publication Number Publication Date
JPS61189431A true JPS61189431A (en) 1986-08-23

Family

ID=12271827

Family Applications (1)

Application Number Title Priority Date Filing Date
JP60029279A Pending JPS61189431A (en) 1985-02-19 1985-02-19 Appreciating method for non-reflecting film

Country Status (1)

Country Link
JP (1) JPS61189431A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989009420A1 (en) * 1988-03-22 1989-10-05 Fujitsu Limited Method of connecting optical waveguide with optical fiber
JPH05107402A (en) * 1991-10-17 1993-04-30 Hoya Corp Optical member having antireflection film
JPH05295872A (en) * 1992-04-16 1993-11-09 Tostem Sera Kk Dry jointing device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989009420A1 (en) * 1988-03-22 1989-10-05 Fujitsu Limited Method of connecting optical waveguide with optical fiber
JPH05107402A (en) * 1991-10-17 1993-04-30 Hoya Corp Optical member having antireflection film
JPH05295872A (en) * 1992-04-16 1993-11-09 Tostem Sera Kk Dry jointing device

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