JPH0439384A - Infrared visible conversion fluorescent substance - Google Patents
Infrared visible conversion fluorescent substanceInfo
- Publication number
- JPH0439384A JPH0439384A JP2144392A JP14439290A JPH0439384A JP H0439384 A JPH0439384 A JP H0439384A JP 2144392 A JP2144392 A JP 2144392A JP 14439290 A JP14439290 A JP 14439290A JP H0439384 A JPH0439384 A JP H0439384A
- Authority
- JP
- Japan
- Prior art keywords
- infrared
- phosphor
- ppm
- concentration
- visible conversion
- 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
- 238000006243 chemical reaction Methods 0.000 title claims description 34
- 239000000126 substance Substances 0.000 title abstract description 5
- 229910052772 Samarium Inorganic materials 0.000 claims abstract description 24
- 229910052684 Cerium Inorganic materials 0.000 claims abstract description 9
- 229910052693 Europium Inorganic materials 0.000 claims abstract description 8
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims abstract 3
- -1 alkaline earth metal chalcogenide Chemical class 0.000 claims abstract 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 67
- KZUNJOHGWZRPMI-UHFFFAOYSA-N samarium atom Chemical compound [Sm] KZUNJOHGWZRPMI-UHFFFAOYSA-N 0.000 claims description 22
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 claims description 7
- OGPBJKLSAFTDLK-UHFFFAOYSA-N europium atom Chemical compound [Eu] OGPBJKLSAFTDLK-UHFFFAOYSA-N 0.000 claims description 7
- 239000011261 inert gas Substances 0.000 abstract description 9
- 230000003287 optical effect Effects 0.000 abstract description 7
- 230000010365 information processing Effects 0.000 abstract description 5
- 239000000203 mixture Substances 0.000 abstract description 5
- 238000005245 sintering Methods 0.000 description 16
- 239000010409 thin film Substances 0.000 description 9
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 8
- 229910052717 sulfur Inorganic materials 0.000 description 8
- 239000011593 sulfur Substances 0.000 description 8
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 7
- JGIATAMCQXIDNZ-UHFFFAOYSA-N calcium sulfide Chemical compound [Ca]=S JGIATAMCQXIDNZ-UHFFFAOYSA-N 0.000 description 7
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 6
- 239000000654 additive Substances 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 239000011812 mixed powder Substances 0.000 description 5
- 229910001954 samarium oxide Inorganic materials 0.000 description 5
- 229940075630 samarium oxide Drugs 0.000 description 5
- FKTOIHSPIPYAPE-UHFFFAOYSA-N samarium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[Sm+3].[Sm+3] FKTOIHSPIPYAPE-UHFFFAOYSA-N 0.000 description 5
- ZEGFMFQPWDMMEP-UHFFFAOYSA-N strontium;sulfide Chemical compound [S-2].[Sr+2] ZEGFMFQPWDMMEP-UHFFFAOYSA-N 0.000 description 5
- 239000000758 substrate Substances 0.000 description 5
- 230000000996 additive effect Effects 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 4
- 230000007547 defect Effects 0.000 description 4
- PQXKHYXIUOZZFA-UHFFFAOYSA-M lithium fluoride Chemical compound [Li+].[F-] PQXKHYXIUOZZFA-UHFFFAOYSA-M 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000012190 activator Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 3
- 229910000420 cerium oxide Inorganic materials 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 description 2
- WUKWITHWXAAZEY-UHFFFAOYSA-L calcium difluoride Chemical compound [F-].[F-].[Ca+2] WUKWITHWXAAZEY-UHFFFAOYSA-L 0.000 description 2
- 229910001634 calcium fluoride Inorganic materials 0.000 description 2
- QDVBBRPDXBHZFM-UHFFFAOYSA-N calcium;selenium(2-) Chemical compound [Ca+2].[Se-2] QDVBBRPDXBHZFM-UHFFFAOYSA-N 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 229910001940 europium oxide Inorganic materials 0.000 description 2
- AEBZCFFCDTZXHP-UHFFFAOYSA-N europium(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Eu+3].[Eu+3] AEBZCFFCDTZXHP-UHFFFAOYSA-N 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000004020 luminiscence type Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 239000008188 pellet Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000001004 secondary ion mass spectrometry Methods 0.000 description 2
- SPVXKVOXSXTJOY-UHFFFAOYSA-N selane Chemical compound [SeH2] SPVXKVOXSXTJOY-UHFFFAOYSA-N 0.000 description 2
- 229910000058 selane Inorganic materials 0.000 description 2
- 229910052711 selenium Inorganic materials 0.000 description 2
- 239000011669 selenium Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 230000000638 stimulation Effects 0.000 description 2
- TYVUSGXGUHEKGS-UHFFFAOYSA-N P.[Se-2].[Sr+2] Chemical compound P.[Se-2].[Sr+2] TYVUSGXGUHEKGS-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 229910052923 celestite Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 238000005240 physical vapour deposition Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- XXCMBPUMZXRBTN-UHFFFAOYSA-N strontium sulfide Chemical compound [Sr]=S XXCMBPUMZXRBTN-UHFFFAOYSA-N 0.000 description 1
- BCTHFFLRHBNYHU-UHFFFAOYSA-N strontium;selenium(2-) Chemical compound [Se-2].[Sr+2] BCTHFFLRHBNYHU-UHFFFAOYSA-N 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
Landscapes
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
- Luminescent Compositions (AREA)
- Transforming Light Signals Into Electric Signals (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は赤外可視変換蛍光体に係わり、特に、赤外入力
光に対する応答速度が速い赤外可視変換蛍光体に関する
。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an infrared-visible converting phosphor, and particularly relates to an infrared-visible converting phosphor that has a fast response speed to input infrared light.
赤外輝尽蛍光体とは、あらかし約短波長の光、あるいは
、Ｘ線、放射線等で励起した後、赤外光で刺激すると可
視域の発光を発生ずる蛍光体である。An infrared stimulable phosphor is a phosphor that emits light in the visible range when excited with light of approximately short wavelength, X-rays, radiation, etc., and then stimulated with infrared light.
以後の記載事項に関する理解を深めるため、ここでは赤
外輝尽蛍光体の動作原理をＣａＳ：Ｂｕ。In order to deepen your understanding of the following items, we will explain the operating principle of the infrared stimulable phosphor using CaS:Bu.
Ｓｍを例にとり第１図に示したケラ−（Ｋｅｌｌｅｒ）
のモデルを用いて説明する。Keller shown in Figure 1 taking Sm as an example.
This will be explained using the following model.
まず、■短波長の光を蛍光体に照射すると蛍光体が励起
され０ｕからＳｍに電子が移動する。次に、■赤外光を
照射すると、その刺激によりＳｍに蓄積されていた電子
が８１１に移動する。■Ｈｕに移動した電子はＥｕの基
底準位に媛和しその際に光を放出する。この時の発光を
赤外輝尽発光と呼んでいる。First, (2) When the phosphor is irradiated with short wavelength light, the phosphor is excited and electrons move from 0u to Sm. Next, (2) When infrared light is irradiated, the electrons accumulated in Sm move to 811 due to the stimulation. (2) The electrons that have moved to Hu soften to the ground level of Eu and emit light at that time. The light emission at this time is called infrared stimulated light emission.
この赤外輝尽発光は赤外線を可視化する手段として注目
され、第二次世界大戦中日米両国で活発に研究され、そ
の結果、硫化カルシウム（ＣａＳ）や硫化ストロンチウ
ム（ＳｒＳ）にユーロピウム（Ｂｕ）とサマリウム（Ｓ
ｍ）、あるいはセリウム（Ｃｅ）とサマリウム（Ｓｍ）
などを添加した蛍光体が赤外可視変換効率の高い蛍光体
として開発された。This infrared stimulated luminescence attracted attention as a means of visualizing infrared light, and was actively researched in both Japan and the United States during World War II. As a result, calcium sulfide (CaS), strontium sulfide (SrS), and europium (Bu) and samarium (S
m), or cerium (Ce) and samarium (Sm)
Phosphors doped with such compounds have been developed as phosphors with high infrared-visible conversion efficiency.
第二次大戦前後の研究により、赤外輝尽蛍光体中に添加
する添加物の最適濃度が明らかにされ、サマリウム濃度
に関しては、蛍光体全重量に対して重量比で５０ ｐｐ
ｍから３ Ｄ Ｏｐｐｍの濃度範囲で添加すると最も赤
外可視変換効率の高い蛍光体が得られるこきが分かった
。Research conducted before and after World War II revealed the optimal concentration of additives added to infrared stimulable phosphors, and the samarium concentration was set at 50 pp by weight relative to the total weight of the phosphor.
It has been found that a phosphor with the highest infrared-visible conversion efficiency can be obtained when added in a concentration range from m to 3D oppm.
サマリウム添加濃度について記載した文献には、例えば
、１９４７年７月に頒布された「ジャーナル 才ブ ジ
アメリカン ケミカルソサイエティ（Ｊｏｕｒｎａｌ
ｏｆ ｔｈｅ Ａｍｅｒｉｃａｎ Ｃｈｅａ＋１ｃａ
ｌ ５ｏｃｉｅｔｙ）」第１７２５頁〜第１７２９頁所
載の「赤外光によって刺激される蛍光体の基本材料とし
てのセレン化ストロンチウムの製造方法とその特性（Ｔ
ｈｅ Ｐｒｅｐａｒａｔｉｏｎ ｏｆ Ｓｔｒｏｎｔｉ
ｕｍＳｅｌｅｎｉｄｅ ａｎｄ ｉｔｓ Ｐｒｏ
ｐｅｒｔｉｅｓ ａｓ ａ Ｂａ５ｅ Ｍａｔ
ｅｒｉａｌ ｆｏｒ Ｐｈｏｓｐｈｏｒｓ Ｓｔｉｍｕ
ｌａｔｅｄ ｂｙ Ｉｎｆｒａｒｅｄ）Ｊと題する論文
があり、この論文の特に「Ｂ、セレン化ストロンチウム
蛍光体の作製法（Ｂ、Ｐｒｅ−ｐａｒａｔｉｏｎ ｏｆ
Ｓｔｒｏｎｔｉｕｍ ５ｅｌｅｎｉｄｅ Ｐｈｏｓｐ
ｈｏｒｓ） 」の章にサマリウム濃度は２００ ｐｐｍ
と記載されている。また例えば、１９５８年９月に頒布
された「フィジカル レビ！ −（Ｐｈｙｓｉｃａｌ
Ｒｅｖｉｅｗ） Ｊ第１１１巻６号第１５３３頁〜第１
５３９頁所載の［赤外輝尽蛍光体に関するクエンチング
、刺激、消耗の研究（Ｑｕｅｎｃｈｉｎｇ、 Ｓｔｉｍ
ｕｌａｔｉｏｎ。Literature describing samarium additive concentrations includes, for example, the Journal of the American Chemical Society, published in July 1947.
of the American Chea+1ca
``Manufacturing method and properties of strontium selenide as a basic material for phosphors stimulated by infrared light (T
he Preparation of Stronti
umSelenide and its Pro
parties as a Ba5e Mat
Erial for Phosphors Stimu
There is a paper entitled "B. Pre-paration of strontium selenide phosphor".
Strontium 5elenide Phosp
hors), the samarium concentration is 200 ppm.
It is stated that. For example, “Physical Rev!
Review) J Vol. 111, No. 6, pp. 1533-1
[Quenching, Stimulation and Depletion Studies on Infrared Stimulated Phosphors] on page 539
ulation.
ａｎｄ Ｂｘｈａｕｔｉｏｎ ５ｔｕｄｉｅｓ ｏｎ
Ｓｏｍｅ ＩｎｆｒａｒｅｄＳｔｉｍｕｌａｂｌｅ Ｐ
ｈｏｓｐｈｏｒｓ） Ｊと題する論文では、蛍光体組成
にライてＳｒＳ、６％ＳｒＳＯ４，６％ＣａＦｚ、０．
０２％Ｂｕ、及び０．０２％Ｓｍと記載しておりサマリ
ウム添加濃度をｐｐｍ表記で示すとほぼ２００ ｐｐｍ
となる。以上例示したように従来の蛍光体ではサマリウ
ムの添加濃度は、蛍光体全重量に対してて重量比で５ｏ
ｐｐｍから３００ ｐｐｍの濃度範囲で添加されている
。and Bxhaution 5tudies on
Some Infrared Stimulable P
phosphors) J, the phosphor composition is SrS, 6% SrSO4, 6% CaFz, 0.
It is written as 0.02%Bu and 0.02%Sm, and the concentration of samarium added is approximately 200 ppm when expressed in ppm.
becomes. As exemplified above, in conventional phosphors, the concentration of samarium added is 50% by weight based on the total weight of the phosphor.
It is added in a concentration range of ppm to 300 ppm.
また、赤外輝尽蛍光体に関する特許としては米国特許第
４８４２９６０号、第４８３９０９２号、第４８３０８
７５号、第４８２２５２０号、第４８１８４ Ｆ４号、
第４８１２６６０号などがあるが、文献同様サマリウム
の添加濃度は、蛍光体全重量に対して重量比で５０ ｐ
ｐｍから３００ ｐｐｍの濃度範囲と記載されている。In addition, patents related to infrared stimulable phosphors include U.S. Patent No. 4842960, U.S. Pat.
No. 75, No. 4822520, No. 48184 F4,
No. 4812660, etc., but as in the literature, the concentration of samarium added is 50 p by weight relative to the total weight of the phosphor.
It is stated that the concentration ranges from pm to 300 ppm.
例えば、米国特許第４８３０８７５号［蛍光体材料と作
製法及び赤外検知素子（Ｐｈｏｔｏｌｕｍｉｎｅｓｃｅ
ｎｔ ｍａｔｅｒｉａｌｓ ａｎｄ ａｓｓｏｃｉａｔ
ｅｄ ｐｒｏｃｅｓｓ ａｎｄ ＋ｎｆ−ｒａｒｅｄ
ｓｅｎｓｉｎｇ ｄｅｖｉｃｅ） Ｊのクレームにはサ
マリウム濃度は蛍光体全重量に対して重量比で５０ｐｐ
ｍから３００ ｐｐｍと記載されている。この濃度領域
で添加する理由としては前記特許明細書第５コラム第６
２行に［前述の添加濃度の特定値は感度などの優れた特
性を与える（Ｔｈｅ ５ｐｅｃ＋ｆｉｃ ｖａｌｕｅ
ｓ ｆｏｒ ｐｏｒｔｉｏｎｓ ｗｈｉｃｈ ａｒｅ
ｇｉｖｅｎａｂｏｖｅ ｐｒｏｖｉｄｅ ｈｉｇｈｌｙ
５ｕｐｅｒｉｏｒ ｃｈａｒａｃｔｅｒ＋ｓｔ＋ｃｓ
５ｕｃｈ ａｓ ５ｅｎｓｉｔｉｖｉｔｙ） Ｊと
記載されているように、この濃度領域でＳｍを添加する
ことにより赤外可視変換効率が高くなるためである。For example, U.S. Pat. No. 4,830,875 [Phosphor material and manufacturing method,
nt materials and associate
ed process and +nf-rared
(sensing device) J's claim states that the samarium concentration is 50pp by weight relative to the total weight of the phosphor.
It is described as 300 ppm from m. The reason for adding in this concentration range is as stated in column 6 of column 5 of the above patent specification.
In the second line, [The above-mentioned specific value of the additive concentration gives excellent characteristics such as sensitivity (The 5pec+fic value
s for portions which are
givenabove provide highly
5superior character+st+cs
This is because the infrared-visible conversion efficiency is increased by adding Sm in this concentration range, as described as 5uch as 5sensitivity) J.
以上述べた様に赤外輝尽蛍光体は赤外可視変換機能を中
心として開発され、開発当初の１９４０年代の集中研究
により赤外可視変換効率の高い蛍光体が実現されたが、
戦後の半導体技術の飛躍的な進展により、シリコン光ダ
イオードなどの赤外線に対する感度の高い検出器が出現
し、赤外光検出器に際して予備励起が必要な赤外輝尽蛍
光体は赤外光検出器としての価値が低下し現在では半導
体レーザーやＹＡＧレーザーなどの赤外光の発光検出や
光学系の調整などに用いられているにすぎない。As mentioned above, infrared stimulable phosphors were developed mainly for their infrared-visible conversion function, and through intensive research in the 1940s when they were first developed, phosphors with high infrared-visible conversion efficiency were realized.
With the dramatic progress in semiconductor technology after the war, detectors with high sensitivity to infrared rays such as silicon photodiodes appeared, and infrared stimulable phosphors that required preliminary excitation were used as infrared photodetectors. Its value has declined, and now it is only used for detecting infrared light emission from semiconductor lasers, YAG lasers, etc., and for adjusting optical systems.
ところが、従来の電子計算機による情報処理能力に限界
が見えはじめ、多数の情報を並列的に処理できる光コン
ピュータの実現が望まれている現在、マカレー（Ａｌａ
ｓｔｅｒ Ｄ ＭｃＡｕｌａｙ）により赤外輝尽蛍光体
を用いて光情報の論理演算が可能であることが示され光
論理演算処理素子媒体として赤外輝尽蛍光体が再び注目
されるに至った。光情報処理の観点から赤外輝尽蛍光体
に要求される特性は、従来の赤外可視変換効率のみでな
く、むしろ赤外入力光に対する高速応答特性が重要であ
る。ここで赤外輝尽蛍光体を用いた場合の応答時間とは
、赤外光を照射してから赤外輝尽発光出力が最大値とな
るまでの立上がり時間と、最大値となってから発光輝度
が最大値の２になるまでの時間を表す立下がり時間を加
えたものを応答時間と言うこととする。However, the information processing capacity of conventional electronic computers is beginning to reach its limits, and optical computers that can process large amounts of information in parallel are now being desired.
ster D McAulay) showed that it was possible to perform logical operations on optical information using infrared stimulable phosphors, and infrared stimulable phosphors once again attracted attention as a medium for optical logic processing elements. From the viewpoint of optical information processing, the characteristics required of infrared stimulable phosphors are not only the conventional infrared-visible conversion efficiency, but also high-speed response characteristics to infrared input light. Here, the response time when using an infrared stimulable phosphor is the rise time from irradiation with infrared light until the infrared stimulable luminescence output reaches its maximum value, and the time it takes to emit light after reaching its maximum value. The response time is the addition of the fall time, which represents the time it takes for the brightness to reach its maximum value of 2.
従来、前述したように赤外輝尽蛍光体は発光効率に主眼
があったため発光効率の報告例はあるが、応答時間につ
いての報告例はほとんど見当らない。Conventionally, as mentioned above, the main focus of infrared stimulable phosphors has been on luminous efficiency, so although there are reports on luminous efficiency, there are almost no reports on response time.
本発明の目的は、赤外輝尽蛍光体において、改良された
特性をもつ赤外可視変換蛍光体を提供することにある。An object of the present invention is to provide an infrared-visible converting phosphor with improved characteristics among infrared stimulable phosphors.
本発明を概説すれば、本発明は赤外可視変換蛍光体に関
する発明であって、アルカリ土類金属カルコゲナイドに
ユーロピウムとサマリウム、あるいはセリウムとサマリ
ウムを添加した赤外可視変換蛍光体において、蛍光体全
重量に対して重量比で３００ ｐｐｍを超え５０００
ｐｐｍ以下のサマリウムを含有することを特徴きする。To summarize the present invention, the present invention relates to an infrared-visible converting phosphor. Weight to weight ratio exceeding 300 ppm and 5000
It is characterized by containing less than ppm of samarium.
本発明者らは、種々の添加濃度の赤外輝尽蛍光体につい
て応答速度を測定した。その結果、従来の濃度領域でＳ
ｒｎを添加した蛍光体はその応答速度が１５０ ｎ５ｅ
ｃから２００ ｎ５ｅｃと長いという欠点があることを
見出した。そして更に活性剤添加濃度と応答速度との関
係を詳細に検討した結果、■赤外入力光に対する応答速
度はＳ＋ｖＪ１度に依存すること■応答速度に関して最
適である濃度領域と赤外可視変換効率に関して最適であ
る濃度領域が異なることを見出した。The present inventors measured the response speed of infrared stimulable phosphors with various additive concentrations. As a result, S
The response speed of the rn-doped phosphor is 150 n5e
It was found that it has the disadvantage of being long, from c to 200 n5ec. Furthermore, as a result of a detailed study of the relationship between the concentration of the activator added and the response speed, we found that: ■ The response speed to infrared input light depends on S + vJ 1 degree. ■ Regarding the optimal concentration range regarding the response speed and the infrared-visible conversion efficiency. It was found that the optimal concentration ranges are different.
本発明は既述の欠点にかんがみなされたものであり、赤
外光に対して高速応答をする濃度領域となるようＳｍ添
加量を制御して蛍光体を製造することにより赤外入力光
に対する応答速度が速い赤外可視変換蛍光体を実現し、
高速情報処理を可能にしたものである。The present invention was made in view of the above-mentioned drawbacks, and the response to infrared input light is improved by manufacturing a phosphor by controlling the amount of Sm added so as to have a concentration range that provides a high-speed response to infrared light. Achieving a fast infrared-visible conversion phosphor,
This enabled high-speed information processing.
以下、本発明の詳細な説明する。The present invention will be explained in detail below.
第２図は赤外輝尽蛍光体に添加した活性剤濃度（ｐｐｍ
、横軸）と赤外可視変換効率（最大変換効率を１００
とした、縦軸）との関係を示す図であり、第２図（ａ）
はユーロピウム濃度を５００ｐｐｍ一定とじＳｍ濃度を
５０ｐｐｍ〜２０００ｐｐｍと変化させた場合の赤外可
視変換効率を示す図であり、第２図ら）はセリウム濃度
を５００ ｐｐｍ −定としＳｍ１ｉ１度を５０ ｐｐ
ｍ 〜２ Ｄ ０１） ｐｐｍと変化させた場合の赤外
可視変換効率を示す図である。Figure 2 shows the concentration (ppm) of the activator added to the infrared stimulable phosphor.
, horizontal axis) and infrared-visible conversion efficiency (maximum conversion efficiency is 100
Fig. 2(a) is a diagram showing the relationship with the vertical axis).
Figure 2 shows the infrared-visible conversion efficiency when the europium concentration is constant at 500 ppm and the Sm concentration is varied from 50 ppm to 2000 ppm.
It is a figure which shows the infrared-visible conversion efficiency at the time of changing it to m~2D01) ppm.
最も高い変換効率に対して９０％の変換効率を与える濃
度領域は従来報告されているように５０ ｐｐｍ〜３０
０ ｐｐｍに存在している。The concentration range that provides the highest conversion efficiency of 90% is 50 ppm to 30 ppm, as previously reported.
Present at 0 ppm.
一方、第３図は赤外輝尽蛍光体に添加した活性剤濃度（
ｐｐｍ 、横軸）と赤外光に対する応答速度（ｎ５ｅｃ
、縦軸）との関係を示す図であり、第３図（ａ）はユー
ロピウム濃度を５００ ｐｐｍ一定とじＳｍ濃度を５０
ｐｐｍ 〜２０００ｐｐｍと変化させた場合の応答速度
を示す図であり、第３図（ｂ）はセリウム濃度を５００
ｐｐｍ一定としＳｍ１度を５０ｐｐｍ〜２０００ ｐ
ｐｍと変化させた場合の応答速度を示す図である。第３
図（ａ）、（ｂ）ともＳｍａ度が５０ｐｐｍ〜３００
ｐｐｍである領域では応答速度が１００ｎｓｅｃ以上で
あるのに対し３００ ＰＰｍを超える領域では応答速度
が急激に速くなり１００ ｎ５ｅｃから１． Ｏｎ５ｅ
ｃへと高速化している。On the other hand, Figure 3 shows the concentration of activator added to the infrared stimulable phosphor (
ppm (horizontal axis) and response speed to infrared light (n5ec
, vertical axis), and FIG. 3(a) shows the relationship between the europium concentration at 500 ppm and the Sm concentration at 50 ppm.
This is a diagram showing the response speed when changing the cerium concentration from ppm to 2000 ppm, and FIG. 3(b) shows the response speed when the cerium concentration is changed from 500 ppm to
Assuming that ppm is constant, Sm1 degree is 50 ppm to 2000 p
It is a figure which shows the response speed when changing with pm. Third
In both figures (a) and (b), the Sma degree is 50 ppm to 300
In the range of ppm, the response speed is 100 nsec or more, whereas in the range of over 300 ppm, the response speed rapidly increases from 100 n5ec to 1.5 sec. On5e
The speed has increased to c.
以上第２図と第３図を比較すれば明らかなように最も高
い赤外可視変換効率を与える濃度領域と１００ ｎ５ｅ
ｃＪＪ下の高速応答を示す濃度領域とは異なり、Ｉ ０
０ ｎ５ｅｃ以下の高速応答を示すＳｍ濃度領域は３０
０ ｐｐｍを超える領域である。Comparing Figures 2 and 3 above, it is clear that the concentration range that provides the highest infrared-visible conversion efficiency is 100 n5e.
Unlike the concentration region showing fast response under cJJ, I 0
The Sm concentration region showing a high-speed response of 0 n5ec or less is 30
This is a region exceeding 0 ppm.
また、Ｓｍ添加濃度を３００９ｐｍを超える濃度とする
と第２図から明らかなように赤外可視変換効率が低下し
、５０００ ｐｐｍを超えると赤外可視変換効率は最大
効率を１０％以下となり実用上問題となるため、５００
０ ｐｐｍ以下の濃度で添加することが望ましい。Furthermore, when the Sm addition concentration exceeds 3009 pm, the infrared-visible conversion efficiency decreases as is clear from Figure 2, and when it exceeds 5000 ppm, the infrared-visible conversion efficiency becomes less than 10% of the maximum efficiency, which is a practical problem. Therefore, 500
It is desirable to add it at a concentration of 0 ppm or less.
以上述べたように、Ｓｍ濃度が３００ ｐｐｍを超え５
０００ ｐｐｍ以下となるように添加することにより１
００ ｎ５ｅｃ以下の高速で応答する赤外輝尽蛍光体が
得られる。As mentioned above, when the Sm concentration exceeds 300 ppm5
1 by adding it to a level of 000 ppm or less.
An infrared stimulable phosphor that responds at a high speed of 00 n5ec or less can be obtained.
以下、本発明の赤外可視変換蛍光体について、実施例に
よって更に具体的に説明するが、本発明はこれら実施例
に限定されない。EXAMPLES Hereinafter, the infrared-visible conversion phosphor of the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.
実施例Ｉ
硫化カルシウムにユーロピウムとサマリウムを添加した
ことを特徴とする赤外可視変換蛍光体について説明する
。Example I An infrared-visible conversion phosphor characterized by adding europium and samarium to calcium sulfide will be described.
上記蛍光体を作製するに当っては、硫化カルシウム１０
０ｇに対しフッ化カルシウムを６ｇ、酸化サマリウムを
０．１５ｇ、酸化ユーロピウムを０．０５ ｇ混合した
後、高温焼結炉中に混合粉末を設置し、１５００℃で２
時間加熱焼結する。In producing the above phosphor, calcium sulfide 10
After mixing 6g of calcium fluoride, 0.15g of samarium oxide, and 0.05g of europium oxide per 0g of powder, the mixed powder was placed in a high-temperature sintering furnace and heated at 1500℃ for 2 hours.
Heat and sinter for a time.
焼結の際蛍光体が酸化することを防ぐために八「などの
不活性ガスを導入することが望ましい。In order to prevent the phosphor from oxidizing during sintering, it is desirable to introduce an inert gas such as 8'.
また不活性ガスに硫化水素を混合したガスや、硫化水素
ガスを導入して焼結すると焼結時の加熱により硫黄成分
が蒸発し蛍光体中に硫黄欠損が生じることを防止できる
ため更に高品質の蛍光体が得られる。In addition, by sintering with a mixture of hydrogen sulfide in an inert gas or hydrogen sulfide gas, the sulfur component evaporates due to the heating during sintering, which prevents sulfur defects from occurring in the phosphor, resulting in even higher quality. of phosphor is obtained.
この様にして得られた蛍光体のＳｍ濃度をＩＣＰ分析に
より検査した結果Ｓｍ濃度は１５００ｐｐｍで、赤外光
に対する応答速度は４０ ｎ５ｅｃであり高速応答の赤
外可視変換蛍光体が得られた。The Sm concentration of the thus obtained phosphor was examined by ICP analysis. As a result, the Sm concentration was 1500 ppm and the response speed to infrared light was 40 n5ec, indicating that an infrared-visible conversion phosphor with high speed response was obtained.
実施例２
硫化ストロンチウムにセリウムとサマリウムを添加した
ことを特徴とする赤外可視変換蛍光体について説明する
。Example 2 An infrared-visible conversion phosphor characterized by adding cerium and samarium to strontium sulfide will be described.
上記蛍光体を作製するに当っては、硫化ストロンチウム
１００ｇに対しフッ化リチウムを２ｇ、酸化サマリウム
を０．１ｇ、酸化セリウムを０．１ｇ混合した後、高温
焼結炉中に混合粉末を設置し、１５００℃で２時間加熱
焼結する。焼結の際蛍光体が酸化することを防ぐために
八ｒなどの不活性ガスを導入することが望ましい。また
不活性ガスに硫化水素を混合したガスや、硫化水素ガス
を導入して焼結すると焼結時の加熱により硫黄成分が蒸
発し蛍光体中に硫黄欠損が生じることを防止できるため
更に高品質の蛍光体が得られる。To produce the above phosphor, 100 g of strontium sulfide was mixed with 2 g of lithium fluoride, 0.1 g of samarium oxide, and 0.1 g of cerium oxide, and then the mixed powder was placed in a high-temperature sintering furnace. , heat and sinter at 1500°C for 2 hours. In order to prevent the phosphor from being oxidized during sintering, it is desirable to introduce an inert gas such as 8R. In addition, by sintering with a mixture of hydrogen sulfide in an inert gas or hydrogen sulfide gas, the sulfur component evaporates due to the heating during sintering, which prevents sulfur defects from occurring in the phosphor, resulting in even higher quality. of phosphor is obtained.
この様にして得られた蛍光体の５ｎｒＪ１度をＴＣＰ分
析により検査した結果５ｎｒａ１度は１０００ ｐｐｍ
で、赤外光に対する応答速度は３ Ｑ ｎ５ｅｃであり
高速応答の赤外可視変換蛍光体が得られた。When 5nrJ1 degree of the phosphor obtained in this way was examined by TCP analysis, 5nra1 degree was 1000 ppm.
The response speed to infrared light was 3 Q n5ec, and an infrared-visible conversion phosphor with high-speed response was obtained.
実施例３
硫化ストロンチウムにセリウムとサマリウムを添加した
ことを特徴とする赤外可視変換蛍光体について説明する
。Example 3 An infrared-visible conversion phosphor characterized by adding cerium and samarium to strontium sulfide will be described.
上記蛍光体を作製するに当っては、硫化ストロンチウム
１００ｇに対しフッ化リチウムを２ｇ、酸化サマリウム
を０．５ｇ、酸化セリウムを０、１ ｇ混合した後、高
温焼結炉中に混合粉末を設置し、１５００℃で２時間加
熱焼結する。焼結の際蛍光体が酸化することを防ぐため
に八「などの不活性ガスを導入することが望ましい。ま
た不活性ガスに硫化水素を混合したガスや、硫化水素ガ
スを導入して焼結すると焼結時の加熱により硫黄成分が
蒸発し蛍光体中に硫黄欠損が生じることを防止できるた
め更に高品質の蛍光体が得られる。To produce the above phosphor, 100 g of strontium sulfide was mixed with 2 g of lithium fluoride, 0.5 g of samarium oxide, and 0.1 g of cerium oxide, and then the mixed powder was placed in a high-temperature sintering furnace. Then, heat and sinter at 1500°C for 2 hours. In order to prevent the phosphor from oxidizing during sintering, it is desirable to introduce an inert gas such as 8".Also, if a mixture of inert gas and hydrogen sulfide or hydrogen sulfide gas is introduced during sintering, Since it is possible to prevent sulfur components from evaporating due to heating during sintering and sulfur defects from occurring in the phosphor, a phosphor of higher quality can be obtained.
この様にして得られた蛍光体のＳｍ濃度をＩＣＰ分析に
より検査した結果Ｓｍｓ度は５０００ ｐｐｍで、赤外
光に対する応答速度は１５ ｎ５ｅｃであり高速応答の
赤外可視変換蛍光体が得られた。The Sm concentration of the thus obtained phosphor was examined by ICP analysis, and the Sms degree was 5000 ppm, and the response speed to infrared light was 15 n5ec, indicating that an infrared-visible conversion phosphor with high speed response was obtained. .
実施例４
セレン化カルシウムにユーロピウムとサマリウムを添加
したことを特徴とする赤外可視変換蛍光体について説明
する。Example 4 An infrared-visible conversion phosphor characterized by adding europium and samarium to calcium selenide will be described.
」１記蛍光体を作製するに当っては、セレン化カルシウ
ム１００ｇに対しフッ化カルシウムを６ｇ、酸化サマリ
ウムを０．０３５ｇ、酸化ユーロピウムを０．０５ ｇ
混合した後、高温焼結炉中に混合粉末を設置し、１５０
０℃で２時間加熱焼結する。焼結の際蛍光体が酸化する
ことを防ぐために八ｒなどの不活性ガスを導入すること
が望ましい。また不活性ガスにセレン化水素を混合した
ガスやセレン化水素ガスを導入して焼結すると焼結時の
加熱によりセレン成分が蒸発し蛍光体中にセレン欠損が
生じることを防止できるため更に高品質の蛍光体が得ら
れる。``1. To prepare the phosphor, 6 g of calcium fluoride, 0.035 g of samarium oxide, and 0.05 g of europium oxide are added to 100 g of calcium selenide.
After mixing, the mixed powder was placed in a high-temperature sintering furnace and heated at 150
Heat and sinter at 0°C for 2 hours. In order to prevent the phosphor from being oxidized during sintering, it is desirable to introduce an inert gas such as 8R. In addition, if a gas containing hydrogen selenide mixed with an inert gas or hydrogen selenide gas is introduced for sintering, the selenium component will evaporate due to the heating during sintering, and selenium defects can be prevented from occurring in the phosphor. Quality phosphor can be obtained.
この様にして得られた蛍光体のＳｍ濃度をＩＣＰ分析に
より検査した結果Ｓｍ濃度は３５０ ｐｌｕｍで、赤外
光に対する応答速度は９０ ｎ５ｅｃであり高速応答の
赤外可視変換蛍光体が得られた。The Sm concentration of the thus obtained phosphor was examined by ICP analysis, and the result was that the Sm concentration was 350 plum, and the response speed to infrared light was 90 n5ec, indicating that an infrared-visible conversion phosphor with high-speed response was obtained. .
実施例５
硫化カルシウムにセリウムとサマリウムを添加した混合
粉末を原料とし物理的蒸着法により薄膜状の蛍光体を作
製した例について説明する。Example 5 An example will be described in which a thin film phosphor was manufactured by physical vapor deposition using a mixed powder of calcium sulfide with cerium and samarium added as a raw material.
上記蛍光体を作製するに当っては、硫化カルシウム１０
０ｇに対し酸化サマリウムを０．１ｇ、酸化セリウムを
０．１ｇ混合した粉末を、加圧形成し蒸着用原料ペレッ
トとする。この原料ベレットを電子ビーム加熱蒸着装置
内に設置し電子ビーム加熱により加熱蒸発させる。この
時同じ真空容器内にあらかじめ洗浄した２５ｍｍＸ２５
ｍｍ角のガラス基板を設置しておき、ガラス基板上に蛍
光体薄膜を形成した。薄膜形成時の基板温度は５００℃
であり、薄膜形成速度は ４００ ｎｍ／ｍｉｎとした
。また、薄膜化により硫黄欠損が生じることを防ぐため
、薄膜形成時に硫化水素を放電によりプラズマ化させ基
板上に照射し硫黄欠損発生防止を図った。In producing the above phosphor, calcium sulfide 10
A powder obtained by mixing 0.1 g of samarium oxide and 0.1 g of cerium oxide per 0 g is pressurized to form pellets of raw material for vapor deposition. This raw material pellet is placed in an electron beam heating evaporation device and is heated and evaporated by electron beam heating. At this time, in the same vacuum container, a 25mm x 25mm
A mm square glass substrate was set up, and a phosphor thin film was formed on the glass substrate. Substrate temperature during thin film formation is 500℃
The thin film formation rate was 400 nm/min. Additionally, in order to prevent sulfur vacancies from occurring due to thinning the film, hydrogen sulfide was turned into plasma by electrical discharge and irradiated onto the substrate during thin film formation to prevent the occurrence of sulfur vacancies.
この様にして得られた薄膜を二次イオン質量スペクトロ
スコピー（ＳＩＭＳ）法によって検査した結果、薄膜中
のサマリウム添加濃度は１１０００ｐｐであり、赤外光
に対する応答速度は３０ ｎ５ｅｃであり高速応答の赤
外可視変換蛍光体が得られた。As a result of inspecting the thin film obtained in this way by secondary ion mass spectroscopy (SIMS), it was found that the concentration of samarium added in the thin film was 11,000 pp, and the response speed to infrared light was 30 n5ec, indicating that it is a fast-response red light. An external visible conversion phosphor was obtained.
また、この薄膜蛍光体の分解能は２００１ｐ／ｍｍであ
り、基板面内で２５００万画素の演算素子が実現された
。この薄膜蛍光体に緑色光で画像情報１と赤外光で画像
情報２を照射することによる２画像間の加算演算を行っ
たところ３０ｎｓｅｃで２５００万演算すなわち、約８
３０Ｔｂｉｔ／ｓｅｃ （テラビット毎秒）の高速演算
が実現され、従来の電子計算機での演算速度的１０６ｂ
ｉｔ／５ｅｃ（ギガビット毎秒）と比較して約８３００
０倍の高速演算が実現された。Furthermore, the resolution of this thin film phosphor was 2001 p/mm, and an arithmetic element with 25 million pixels was realized within the substrate surface. When this thin film phosphor was irradiated with image information 1 using green light and image information 2 using infrared light, an addition operation between the two images was performed, and 25 million operations were performed in 30 ns, that is, approximately 8
High-speed calculation of 30Tbit/sec (terabit per second) has been realized, which is faster than the calculation speed of 106b on conventional electronic computers.
Approximately 8300 compared to it/5ec (gigabits per second)
Achieved 0 times faster calculation.
以上述べたように、赤外可視変換蛍光体を本発明構成の
赤外可視変換蛍光体とすること、すなわち、蛍光体全重
量に対して重量比で３００ｐｐｍを超え、５０００ ｐ
ｐｍ以下のサマリウムを含有することを特徴とする赤外
可視変換蛍光体とすること、によって、従来技術の有し
ていた課題を解決して、赤外入力光に対する応答速度が
早い赤外可視変換蛍光体をを提供することができ、ひい
ては情報処理速度の速い光論理演算素子の実現を可能に
した。As described above, the infrared-visible converting phosphor is an infrared-visible converting phosphor having the structure of the present invention, that is, the weight ratio exceeds 300 ppm with respect to the total weight of the phosphor, and 5000 ppm is used.
By using an infrared-visible conversion phosphor characterized by containing samarium of pm or less, the problems of the conventional technology can be solved, and the infrared-visible conversion can have a fast response speed to infrared input light. This made it possible to provide a phosphor, which in turn made it possible to realize an optical logic operation element with a high information processing speed.
第１図は本発明の赤外可視変換蛍光体の動作原理を示す
図、第２図はサマリウム（Ｓｍ）添加濃度と赤外可視変
換効率との関係を示す図、第３図はサマリウム（Ｓｍ）
添加濃度と赤外光に対する応答速度との関係を示す図で
ある。
特許出願人 日本電信電話株式会社
代 理 人 中 本 宏量
井 上 昭同
吉 嶺 桂第１図Figure 1 is a diagram showing the operating principle of the infrared-visible conversion phosphor of the present invention, Figure 2 is a diagram showing the relationship between samarium (Sm) doping concentration and infrared-visible conversion efficiency, and Figure 3 is a diagram showing the relationship between samarium (Sm) doping concentration and infrared-visible conversion efficiency. )
FIG. 3 is a diagram showing the relationship between additive concentration and response speed to infrared light. Patent applicant: Nippon Telegraph and Telephone Corporation Representative: Hiroshi Nakamoto
Akito Inoue
Katsura Yoshimine Figure 1
Claims (1)
とサマリウム、あるいはセリウムとサマリウムを添加し
た赤外可視変換蛍光体において、蛍光体全重量に対して
重量比で３００ｐｐｍを超え５０００ｐｐｍ以下のサマ
リウムを含有することを特徴とする赤外可視変換蛍光体
。1. An infrared-visible conversion phosphor in which europium and samarium or cerium and samarium are added to alkaline earth metal chalcogenide, characterized by containing samarium in a weight ratio of more than 300 ppm and less than 5000 ppm based on the total weight of the phosphor. Infrared-visible conversion phosphor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2144392A JP2631759B2 (en) | 1990-06-04 | 1990-06-04 | Infrared-visible conversion phosphor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2144392A JP2631759B2 (en) | 1990-06-04 | 1990-06-04 | Infrared-visible conversion phosphor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0439384A true JPH0439384A (en) | 1992-02-10 |
| JP2631759B2 JP2631759B2 (en) | 1997-07-16 |
Family
ID=15361085
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2144392A Expired - Lifetime JP2631759B2 (en) | 1990-06-04 | 1990-06-04 | Infrared-visible conversion phosphor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2631759B2 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0236296A (en) * | 1988-04-21 | 1990-02-06 | Quantex Corp | Thin-film photoluminescent article and its manufacture |
-
1990
- 1990-06-04 JP JP2144392A patent/JP2631759B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0236296A (en) * | 1988-04-21 | 1990-02-06 | Quantex Corp | Thin-film photoluminescent article and its manufacture |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2631759B2 (en) | 1997-07-16 |
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