熱中性子ラジオグラフィ用-新規ＬｉＦシンチレータ、 平成23年1月16日 KUR研究会 熱中性子ラジオグラフィ用-新規ＬｉＦシンチレータ、 および輝度向上フィルムの評価 ○飯倉 寛1，筒井 紀彰2，中村 龍也1，片桐 政樹1，呉田 昌俊1， 久保 純3，松林 政仁1 原子力機構1，秩父富士2，日産自動車3
新規LiFシンチレータの開発・評価 輝度アップシートの導入
新規LiFシンチレータの共同開発 Scintillation decay characteristics 従来品 AST社製 従来品 AST社製 化成オプトニクス製 ＜NRコンバータ＞ Scintillation decay characteristics Elapsed time (ms) Output voltage from PMT (V) 1 2 3 4 5 6 7 8 -0.04 -0.08 -0.12 -0.16 ZnS (Ag):Al/6Li ZnS (Ag):Cl/6Li ㈱秩父富士製 ＜ZNSLB-L300-Al-0510＞ ZnS/6 LiF/Inorganic-binder = 2:1:1 thickness : 300mm
Fast components Slow components Sample Intensity Half-life Intensity Half-life After grow ratio (0-8 ms) periods (ms) (40-80 ms) periods (ms) (slow/fast) ZnS(Ag):Al/6Li 130081 2.49 20818 22.1 0.032 (New scintillator) ZnS(Ag):Cl/ 6Li 113113 2.74 26029 22.6 0.046 (AST) Comparison of the scintillation decay characteristics for thermal neutrons 4
Comparison of brightness (a) and MTF(b) C-CCD camera C4880 (Hamamatsu) a 200mm lens (Nikon Micro-Nikkor, F=4.0) (a) (b) □ Conventional scintillator ○ New scintillator Exponential fit Brightness MTF □ Conventional scintillator ○ New scintillator Exposure time (second) Line Pairs/mm Conventional scintillator : 3.61LP/mm New scintillator : 3.04LP/mm 5
The designed Gd-resolution mask for neutron imaging 50 mm The designed Gd-resolution mask for neutron imaging (a) (b) 50 mm LP2.0mm 1.0 0.4, 0.8 0.6 0.2 0.3, 0.7 0.5, 0.9 1.5 3.0 f 4.0mm 2.0 0.8 0.7 - 0.4 0.3 - 0.1 4.0 LP2.0mm 1.5 1.2 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 6
A single frame neutron image of the Gd-resolution mask No.1 used the high frame-rate Imaging system and the new scintillator. The frame rate of each image was 2000 (a) and 15000fps (b). FASTCAM-MAX 120K (Photron) I.I.（C9547MOD Hamamatsu, gain: min. 500 – max.990) NIKKOR 85mm lens (Nikon, F=1.4). (a) Gain 560 (b) Gain 750 200 pixels 7
Visualization of oil flow in a running car engine Visualization of oil flow in a running car engine. (a) The appearance photograph of the engine used in the experiment. (b) A schematic illustration of the view area. (c) a single frame from the continuous neutron images at 2000fps inside an engine driven 1600 rotations per minutes. (a) (b) (c) 8
新規LiFシンチレータの開発・評価 輝度アップシートの導入 9
ＢＥＦ 住友3M株式会社HPより抜粋 http://www.mmm.co.jp/display/bef/index.html
BEF II 90/24 Prism pitch: 24 mm Prismatic Structure: 13 mm Polyester Substrate: 127 mm Scintillator 4300 7100 10600 Silica glass BEF II 90/24 11
発光傾向（簡易的実測値より） BEF scintillator neutron neutron 12
Evaluation of the spatial resolution by using BEF. The neutron transmission image of the Gd-resolution mask No.2 (a) withoutBEF, (b) with two BEF stacked perpendicularly None + two BEF (a) (b) 13
MTF using conventional scintillator with BEF. The curves were approximated using the exponential function in order to calculate each 10% MTF. MTF Line Pairs/mm 10% of MTF none: 2.12 LP/mm +BEF: 0.94 LP/mm 14
1mm程度の分解能で十分なニーズであれば、さらなる高速動態撮像が可能に イメージングに限らず、また中性子に限らず、 New scintillator + BEF Conventional scintillator (a) (b) 0.9 sec 0.15 sec 1mm程度の分解能で十分なニーズであれば、さらなる高速動態撮像が可能に イメージングに限らず、また中性子に限らず、 シンチレータ等の発光をカメラ撮像するタイプのシステムであれば適用可能 15
ＴＮＲＦ マシンタイム動向
ＪＲＲ－３ 運転計画（予定）