Charbonnier F M, Barbour J P, Dyke W P
Radiology. 1975 Oct;117(1):165-72. doi: 10.1148/117.1.165.
The physical designs of field-emission and conventional x-ray tubes are compared, and the physical and geometric source properties are translated into optical and resolution characteristics using modulation transfer functions calculated for idealized and practical sources and verified by star test pattern measurements. The field-emission design has several advantages: axial symmetry, circular shape, and a relatively favorable intensity distribution of the focal spot; in addition, the focal spot size is independent of the tube current. These advantages greatly enhance uniformity over the field of view and may increase resolution by a factor of 2 for a given nominal source size, thus largely ofsetting the greater physical size of present field-emission sources.
比较了场发射X射线管和传统X射线管的物理设计，并使用针对理想化和实际源计算的调制传递函数将物理和几何源特性转化为光学和分辨率特性，这些函数通过星型测试图案测量得到验证。场发射设计具有几个优点：轴对称、圆形形状以及焦斑相对良好的强度分布；此外，焦斑尺寸与管电流无关。这些优点极大地提高了视野内的均匀性，并且对于给定的标称源尺寸，分辨率可能提高两倍，从而在很大程度上抵消了当前场发射源较大的物理尺寸。
