JPH0316933A - Glass for near-infrared absorption filters - Google Patents
Glass for near-infrared absorption filtersInfo
- Publication number
- JPH0316933A JPH0316933A JP1152913A JP15291389A JPH0316933A JP H0316933 A JPH0316933 A JP H0316933A JP 1152913 A JP1152913 A JP 1152913A JP 15291389 A JP15291389 A JP 15291389A JP H0316933 A JPH0316933 A JP H0316933A
- Authority
- JP
- Japan
- Prior art keywords
- glass
- infrared absorption
- cuo
- near infrared
- resistance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000011521 glass Substances 0.000 title abstract description 45
- 238000010521 absorption reaction Methods 0.000 title abstract description 17
- 239000000203 mixture Substances 0.000 abstract description 12
- 230000007774 longterm Effects 0.000 abstract description 5
- 239000005365 phosphate glass Substances 0.000 abstract description 5
- 230000035945 sensitivity Effects 0.000 abstract description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract 1
- 230000005540 biological transmission Effects 0.000 abstract 1
- 229910052593 corundum Inorganic materials 0.000 abstract 1
- 230000001747 exhibiting effect Effects 0.000 abstract 1
- 239000011159 matrix material Substances 0.000 abstract 1
- 229910001845 yogo sapphire Inorganic materials 0.000 abstract 1
- 238000002834 transmittance Methods 0.000 description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 238000002844 melting Methods 0.000 description 8
- 230000008018 melting Effects 0.000 description 8
- 230000003595 spectral effect Effects 0.000 description 7
- 239000000126 substance Substances 0.000 description 7
- 230000003287 optical effect Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 3
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 229910006853 SnOz Inorganic materials 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910000272 alkali metal oxide Inorganic materials 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 239000005304 optical glass Substances 0.000 description 1
- 239000000075 oxide glass Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000010583 slow cooling Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C3/00—Glass compositions
- C03C3/12—Silica-free oxide glass compositions
- C03C3/16—Silica-free oxide glass compositions containing phosphorus
- C03C3/19—Silica-free oxide glass compositions containing phosphorus containing boron
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Optical Filters (AREA)
- Glass Compositions (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、近赤外線領域、特に波長８００〜１０００ｎ
．ｍの光を効率的に吸収し、尚かっ可視域において高い
透過率を有するフィルタ用ガラスに関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to near-infrared regions, particularly wavelengths of 800 to 1000 nm.
．． The present invention relates to a filter glass that efficiently absorbs m light and has high transmittance in the visible range.
本発明のフィルタガラスは、主にカラー撮影機器におけ
る受光素子の感度補正用フィルタなどとして使用される
。The filter glass of the present invention is mainly used as a filter for correcting the sensitivity of a light receiving element in color photographic equipment.
従来の技術
カラー撮影機器に使用される撮像管あるいは固体撮像素
子の分光感度は可視域から近赤外域の広い範囲にわたっ
ている。このため近赤外域の８００〜９００ｎｍを吸収
し可視域を透過して通常の視感度に補正する近赤外吸収
フィルタは必要欠くべからざる光部品となっている。こ
のようなフィルタ用のガラスは、８００ｎｍ以上の波長
域における吸収係数が大きく、４００〜７０（ｌｎｍの
波長域においては高い透過性を持たなければならない。BACKGROUND OF THE INVENTION The spectral sensitivities of image pickup tubes or solid-state image sensors used in conventional color imaging equipment range widely from the visible region to the near-infrared region. For this reason, a near-infrared absorption filter that absorbs 800 to 900 nm in the near-infrared region and transmits the visible region to correct the visibility to normal visibility has become an indispensable optical component. Glass for such a filter must have a large absorption coefficient in a wavelength range of 800 nm or more, and high transmittance in a wavelength range of 400 to 70 nm.
そして、このようなガラスはリン酸系ガラスにＣｕＯを
添加することによって得られる。すなわち、波長８００
ｎｍ付近に吸収帯を持つＣｕ２＋がＰ２Ｏ，を主成分と
したガラス中に存在した場合、８００〜ｌｏ００ｎｍの
波長域の光を十分に吸収し、波長５００ｎｍを中心とし
た可視域において高い透過率を有するガラスとなる事が
知られている。しかしながら、このガラスは吸湿性の強
いＰ２Ｏ，から形成されているため通常の使用に対して
十分な耐水性、耐候性を得ることが非常に？難で、長期
間使用するとガラス表面が変質し、光学的特性が劣化す
る。特公昭６０−４９１４２号公報及び特公昭６３−２
５２４５号公報などに、これらの耐水性、耐候性を改良
したガラスがある。Such glass can be obtained by adding CuO to phosphate glass. That is, the wavelength is 800
When Cu2+, which has an absorption band around nm, exists in a glass mainly composed of P2O, it will sufficiently absorb light in the wavelength range of 800 to 1000 nm, and exhibit high transmittance in the visible range centered on the wavelength of 500 nm. It is known that glass with However, since this glass is made of P2O, which has strong hygroscopic properties, it is difficult to obtain sufficient water resistance and weather resistance for normal use. If used for a long period of time, the glass surface will change in quality and the optical properties will deteriorate. Special Publication No. 60-49142 and Special Publication No. 63-2
There are glasses with improved water resistance and weather resistance, such as in Japanese Patent No. 5245.
発明が解決しようとする課題
Ｈにガラスの化学的耐久性を向上させるためには、基礎
ガラス組成に化学的耐久性が良好で、ガラス構造の一部
を形成しつる化合物を導入すればよいことが知られてい
る。例えば、Ａ１■０３はこのような場合非常に効果的
である。またこのことと同時にガラス組成中のアルカリ
成分の含有量を少なくすることも化学的耐久性の向上に
効果がある。前記公告公報においても、このような手法
が用いられている。しかしながらＡ１２Ｏ３を大量に導
入したり、また、アルカリ成分の含有量を極端に少なく
するため、溶融温度が高くなり、ガラスの脱泡、均質化
が難しくなる。一方、このガラス中に含まれるＣｕ２“
は高温下でＣｕ“に変化ずる傾向があり、その場合、近
赤外領域における吸収係数が？さくなり、十分な光学的
性能が得られなくなる。つまり、化学的耐久性を向上さ
せるために、溶融温度が高いガラス組成を用いる従来の
手法を使用した場合、Ｃｕ２＋かＣｕ“に変化してしま
う傾向かあるために、光学的特性を劣化させることにな
る。Problem H that the invention aims to solve is that in order to improve the chemical durability of glass, it is sufficient to introduce a compound that has good chemical durability and forms a part of the glass structure into the basic glass composition. It has been known. For example, A1■03 is very effective in such cases. At the same time, reducing the content of alkaline components in the glass composition is also effective in improving chemical durability. Such a method is also used in the above-mentioned publication. However, since a large amount of A12O3 is introduced or the content of the alkali component is extremely reduced, the melting temperature becomes high, making it difficult to defoam and homogenize the glass. On the other hand, Cu2“ contained in this glass
tends to change to Cu" at high temperatures, and in that case, the absorption coefficient in the near-infrared region decreases, making it impossible to obtain sufficient optical performance. In other words, in order to improve chemical durability, If a conventional approach using a glass composition with a high melting temperature is used, there is a tendency for the glass composition to change to Cu2+ or Cu'', thereby degrading the optical properties.
また特公昭６３−２５２４５号公報には、ＳｊＯ。、Ｓ
ｎＯ■を添加する方法が述べられているが、Ｓ】０■は
、近赤外において吸収係数を小さくし、ＳｎＯ■は、可
視域において透過率を下げる。また両成分とも、リン酸
系ガラス中に入れた場合ガラスを失透し易くする傾向が
ある。Also, in Japanese Patent Publication No. 63-25245, SjO. , S
A method of adding nO■ is described, but S]0■ reduces the absorption coefficient in the near infrared, and SnO■ lowers the transmittance in the visible region. Furthermore, both components tend to make the glass more likely to devitrify when added to a phosphate glass.
したがって本発明においては、光学的特性に影響を及ぼ
さないような比較的低い温度で溶融が可能で、ＳｎＯｚ
、Ｓｌ０２などを含まず、十分な化学的耐久性を持つガ
ラスを新たに提供することを目的とする。Therefore, in the present invention, it is possible to melt SnOz at a relatively low temperature that does not affect the optical properties.
, Sl02, etc., and has sufficient chemical durability.
課題を解決するための手段
本発明者は、前述のような点を考慮して、鋭意研究した
結果アルカリ酸化物を含むリン酸塩系ガ？スにおいて、
十分な性能を有する近赤外吸収フィルタ用ガラス組成を
見出した。すなわち重量百分率でＰ２Ｏ５が６５．０〜
７５．０％． Ａｌ■０３が１１．０〜１４．０％、Ｂ
２Ｏ３が０〜４．０％、Ｋ２Ｏが３．０〜９．０％、Ｍ
ｇＯが２．０ 〜６．０％、ＺｎＯが０〜４．０％、Ｃ
ｕＯが１．５〜４．０％の組成範囲にあることを特徴と
する近赤外吸収フィルタ用ガラスである。本発明のガラ
ス組成を前記の範囲に限定した理由は次に示すとおりで
ある。Means for Solving the Problems The inventor of the present invention took the above points into consideration and, as a result of intensive research, discovered a phosphate-based gas containing an alkali oxide. In the
We have discovered a glass composition for near-infrared absorption filters that has sufficient performance. That is, P2O5 in weight percentage is 65.0~
75.0%. Al■03 is 11.0-14.0%, B
2O3 0-4.0%, K2O 3.0-9.0%, M
gO 2.0 to 6.0%, ZnO 0 to 4.0%, C
This is a near-infrared absorption filter glass characterized by having uO in a composition range of 1.5 to 4.0%. The reason why the glass composition of the present invention is limited to the above range is as follows.
Ｐ２Ｏ５は、ガラス網目を構成するための主成分である
が、６５％未満では近赤外域における吸収係数が小さく
、７５％を超えると長期間の使用に耐えつる耐水性、耐
候性を得ることが困難になる。P2O5 is the main component for forming the glass network, but if it is less than 65%, the absorption coefficient in the near-infrared region is small, and if it exceeds 75%, it is difficult to obtain water resistance and weather resistance that can withstand long-term use. It becomes difficult.
Ａ１２Ｏ３は、耐水性、耐候性を向上させるためには有
効な成分であるが、１１％未満では長期間の使用に耐え
つる耐水性、耐候性を得ることが困難になり、ｉ４％を
超えるとガラスの溶融温度が高くなり、本発明の目的で
ある低温での溶融が不可能となる。A12O3 is an effective component for improving water resistance and weather resistance, but if it is less than 11%, it will be difficult to obtain water resistance and weather resistance that can withstand long-term use, and if it exceeds i4%. The melting temperature of the glass increases, making it impossible to melt at low temperatures, which is the objective of the present invention.
Ｂ２Ｏ３は、ガラスの安定化に有効な成分であるが、４
％を超えるとガラスの耐候性が著しく悪くなる。B2O3 is an effective component for stabilizing glass, but 4
If it exceeds %, the weather resistance of the glass will deteriorate significantly.
Ｋ２Ｏは、３％未満ではガラスの溶融温度が高くなり、
８％を超えると耐水性、耐候性ともに著しく悪くなる。If K2O is less than 3%, the melting temperature of the glass will increase,
If it exceeds 8%, both water resistance and weather resistance will deteriorate significantly.
ＭｇＯは、 ２％未満の場合、長期間の使用に耐えつる
耐水性、耐候性が得られず、６％を超えるとガラスの溶
融温度が高くなり、低温でのガラスの溶融が困難になる
。When MgO is less than 2%, water resistance and weather resistance that can withstand long-term use cannot be obtained, and when it exceeds 6%, the melting temperature of the glass becomes high, making it difficult to melt the glass at low temperatures.
ＺｎＯは、４％を超えるとガラスが失透投し易くなる。When ZnO exceeds 4%, the glass tends to devitrify.
ＣｕＯは１．５％未満では波長８００ 〜ｌ０００ｎｍ
において十分な吸収係数が得られず、４．０％を超える
と可視域において高い透過率が得られない。If CuO is less than 1.5%, the wavelength is 800 to 1000 nm.
If it exceeds 4.0%, high transmittance in the visible range cannot be obtained.
本発明によると前述の組成範囲にあるガラスは、近赤外
領域における十分大きな吸収係数と可視領域における高
い透過率を有し、かつ化学的耐久性がきわめて良好な近
赤外吸収フィルタ用ガラスである。According to the present invention, the glass having the above-mentioned composition range is a glass for near-infrared absorption filters that has a sufficiently large absorption coefficient in the near-infrared region, high transmittance in the visible region, and has extremely good chemical durability. be.
実施例
次に本発明の実施例を第１表に示す。表中のガラス組成
はすべて重量百分率で示し、耐水性は日本光学硝子工業
会規格のガラスの化学的耐久性（粉末法）の測定による
級分類で示す。温度は、ガラス溶融時の最高温度、Ｔ
５０Ｇは波長５００ｎｍ、Ｔ ７００は波長７００ｎｍ
における厚さ１ｍｍでの透過率である。Examples Examples of the present invention are shown in Table 1. All glass compositions in the table are shown in weight percentages, and water resistance is shown in classification based on the measurement of glass chemical durability (powder method) according to the Japan Optical Glass Industry Association standards. The temperature is the maximum temperature during glass melting, T
50G has a wavelength of 500nm, T 700 has a wavelength of 700nm
This is the transmittance at a thickness of 1 mm.
（以下余白）
第ｌ表
本発明のフィルタ用ガラスは、所定の酸化物ガラスが得
られるように各成分の原料として、おのおの相当する酸
化物、水酸化物、炭酸塩、硝酸塩等を使用し、ガラス重
量で１５０ｇとなるように所定の割合で秤量し、十分混
合した後白金製の坩堝内に投入して電気炉内で、９５０
℃〜１１５０℃で８〜１５時間で溶融、撹拌、清澄を行
なった後、金型内に鋳込み徐冷して得られた。また（：
ｕ”を得るために溶融、清澄は大気中で行なった。(Leaving space below) Table 1 The filter glass of the present invention uses corresponding oxides, hydroxides, carbonates, nitrates, etc. as raw materials for each component in order to obtain the specified oxide glass. Weigh the glass at a predetermined ratio so that the glass weight is 150 g, mix thoroughly, then put it into a platinum crucible and heat it in an electric furnace for 950 g.
After melting, stirring and clarifying at 1150°C for 8 to 15 hours, the mixture was poured into a mold and slowly cooled. Also(:
Melting and fining were carried out in the air to obtain u''.
耐水性、透過率は徐冷後に、得られたガラスを所望の形
に加工あるいは研磨して試料とし、測定した。Water resistance and transmittance were measured by processing or polishing the obtained glass into a desired shape after slow cooling to prepare a sample.
本発明において得られた、近赤外吸収フィルタ用ガラス
の分光透過率曲線を第１図に示した。なお、図中におい
て、曲線Ａは実施例２、曲線Ｂは実施例１、曲線Ｃは比
較例１１のそれぞれの分光透過率曲線である。The spectral transmittance curve of the near-infrared absorption filter glass obtained in the present invention is shown in FIG. In the figure, curve A is the spectral transmittance curve of Example 2, curve B is the spectral transmittance curve of Example 1, and curve C is the spectral transmittance curve of Comparative Example 11.
発明の効果
本発明によるＣｕＯを添加したリン酸塩系ガラスを母体
とする近赤外吸収フィルタ用ガラスは、長期間の使用に
耐えつる耐水性、耐候性を持ち、かつ、近赤外域におけ
る効率のよい吸収係数と可視域における高い透過率を有
するので、カラー撮影機器に使用される撮像素子の分光
感度補正用フィルタとして有用である。Effects of the Invention The glass for near-infrared absorption filters based on CuO-added phosphate glass according to the present invention has water resistance and weather resistance that can withstand long-term use, and has high efficiency in the near-infrared region. Since it has a good absorption coefficient and high transmittance in the visible range, it is useful as a filter for correcting the spectral sensitivity of an image sensor used in color photographic equipment.
第１図は、本発明ガラス及び従来ガラスの分光透過率曲
線である。
９
１０FIG. 1 shows spectral transmittance curves of the glass of the present invention and the conventional glass. 9 10
Claims (1)
ｌ＿２Ｏ＿３が１１．０〜１４．０％、Ｂ＿２Ｏ＿３が
０〜４．０％、Ｋ＿２＿Ｏが３．０〜９． ０％、ＭｇＯが２．０〜６．０％、ＺｎＯが０〜４．０
％、ＣｕＯが１．５〜４．０％からなるガラス組成を有
する近赤外吸収フィルタ用ガラス。[Claims] P_2O_5 is 65.0 to 75.0% in weight percentage, A
l_2O_3 is 11.0-14.0%, B_2O_3 is 0-4.0%, and K_2_O is 3.0-9. 0%, MgO 2.0-6.0%, ZnO 0-4.0
%, CuO is 1.5 to 4.0%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1152913A JP2731422B2 (en) | 1989-06-15 | 1989-06-15 | Glass for near infrared absorption filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1152913A JP2731422B2 (en) | 1989-06-15 | 1989-06-15 | Glass for near infrared absorption filter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0316933A true JPH0316933A (en) | 1991-01-24 |
| JP2731422B2 JP2731422B2 (en) | 1998-03-25 |
Family
ID=15550884
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1152913A Expired - Fee Related JP2731422B2 (en) | 1989-06-15 | 1989-06-15 | Glass for near infrared absorption filter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2731422B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0560913A (en) * | 1991-08-30 | 1993-03-12 | Hoya Corp | Optical filter structure |
| JPH06234546A (en) * | 1993-02-08 | 1994-08-23 | Toshiba Glass Co Ltd | Near infrared-ray cutting filter glass |
| JPH09185944A (en) * | 1995-10-30 | 1997-07-15 | Philips Electron Nv | Manufacture of low pressure mercury discharge lamp and low pressure mercury discharge lamp |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5580737A (en) * | 1978-12-11 | 1980-06-18 | Toshiba Glass Co Ltd | Colored glass |
-
1989
- 1989-06-15 JP JP1152913A patent/JP2731422B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5580737A (en) * | 1978-12-11 | 1980-06-18 | Toshiba Glass Co Ltd | Colored glass |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0560913A (en) * | 1991-08-30 | 1993-03-12 | Hoya Corp | Optical filter structure |
| JPH06234546A (en) * | 1993-02-08 | 1994-08-23 | Toshiba Glass Co Ltd | Near infrared-ray cutting filter glass |
| JPH09185944A (en) * | 1995-10-30 | 1997-07-15 | Philips Electron Nv | Manufacture of low pressure mercury discharge lamp and low pressure mercury discharge lamp |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2731422B2 (en) | 1998-03-25 |
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