| 摘要 |
PROBLEM TO BE SOLVED: To provide a mammography screen causing the amount of screen structure noise to be lowered. SOLUTION: This photostimulable storage phosphor screen includes storage phosphor particles dispersed in a binder. The particles have particle size distribution with d<SB>99</SB>of 15μm or less where d<SB>99</SB>designates a particle size limit. In cases where phosphor powder particles of 1 wt.% or less, exceeding this limit, exist in phosphor powder, a structure noise parameter DQE2<SB>rel</SB>exceeds the value of 0.70. The ratio of d<SB>99</SB>(expressed inμm) to DQE2<SB>rel</SB>is equal to or less than 25:1 while DQE2<SB>rel</SB>is the ratio of DQE2 of 22mR dose to DQE2 of 3mR dose as is expressed by an equation DQE2<SB>rel</SB>=DQE2(22mR)/DQE2(3mR). It represents the amount of screen structure noise in the whole of spatial frequency range. COPYRIGHT: (C)2007,JPO&INPIT
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