诊断用X-射线成像设备.通用和大图形防散射滤栅的特性

[中文适用范围]： 本国际标准适用于医疗诊断X射线成像设备中使用的防散射网格。防散射网格用于减少特别是在患者体内图像接收区域产生的散射辐射的发生率，从而提高 X 射线图案的对比度。本国际标准规定了防散射网格特性的定义、测定和指示。在本标准中仅考虑线性网格。由于目前仅聚焦网格用于乳房X线照相术@，因此该标准仅限于涉及乳房X线照相抗散射网格的聚焦网格。本标准不适用于验收测试。该标准不涵盖网格区域内的性能同质性。本标准旨在用于确定测试条件下防散射栅的特性。责任组织所在地通常不具备这些条件。 [外文原描述]： IEC 60627:2013 is applicable to anti-scatter grids used in medical diagnostic X-ray imaging equipment. Anti-Scatter Grids are used to reduce the incidence of scattered radiation, produced particularly in the body of the patient, upon the image reception area and thus to improve the contrast of the X-ray pattern. This International Standard specifies the definitions, determination and indication of characteristics of anti-scatter grids. In this standard only linear grids are considered. Since at present only focused grids are used in mammography, this standard is restricted to focused grids where mammographic anti-scatter grids are concerned. This standard is not intended to be applied for acceptance tests. This standard does not cover the homogeneity of performance over the area of a grid. This standard is intended to be applied for the determination of the characteristics of anti-scatter grids under test conditions. These conditions are not usually available at the site of the responsible organization. This third edition cancels and replaces the second edition published in 2001, and constitutes a technical revision. In this revision calcium tungstate phosphor fluorescent screens, which are no longer available, have been replaced by gadolinium oxysulphide (GOS) fluorescent screens. Further, a new quality parameter is introduced: the Image Improvement Factor or Q-factor, which better describes the properties of the anti-scatter grid, especially for digital detector applications. Further differences between this third edition and the previous second edition are: - new instrumentation is prescribed for measurements of the transmission of primary radiation, the transmission of scattered radiation and the transmission of total radiation, because fluorescent screens made of calcium tungstate phosphors are outdated and are no longer available; - the definition of the phantom used for measurements of the transmission of primary radiation, the transmission of scattered radiation and the transmission of total radiation is modified and references to IEC 61267 are omitted; - and the radiation conditions used for the measurements have been adapted and are now the RQR and RQR-M conditions specified in IEC 61267:2005.