シンチレータ（蛍光物質）

scintillator (fluorescent substance)

[目次：検出系]

電子線、電磁波などのエネルギーを吸収して蛍光を発する物質。背後に置かれる光電変換器の感度特性に合わせて蛍光の色、残光の長さを考慮して蛍光物質が選ばれる。蛍光板上での電顕像の可視化用(黄緑色、残光～100ms)、二次電子検出器での電子線強度測定用(青色、残光～μs)、電顕像などの撮影用のCCDの前段に置かれるYAG(青白色、残光～μs)などに使われている。

The scintillator is a substance that emits fluorescence by absorbing the energy of an electron beam or electromagnetic wave. A fluorescent substance for the "scintillator" is selected by taking account of the fluorescence wavelength (color) and its persistence time according to the sensitivity characteristic of a photoelectric converter placed behind the scintillator. The scintillator is used for various purposes: a fluorescent screen (yellow-green light, persistence light: ～100 ms) to visualize a TEM image, a secondary-electron detector (blue light, persistence light: ～μs) to measure the beam intensity of secondary electrons, and a TEM image detector (YAG) (blue white light, persistence light: ～μs) placed before a CCD.