【摘要】 在阐述了用台阶法测量辐射成像系统扩展函数 (SF)的原理基础上 ,针对该方法所产生的误差情况进行了分析 ,并对各种因素 (如台阶与光轴的夹角、台阶与光轴的距离及台阶厚度等 )的影响程度作了详细的对比 ,获得了测量系统扩展函数实验布局的指导原则 ,同时指出了在该类测量实验中应注意的问题更多还原

【Abstract】 After expatiating upon the principle of the measurement of spread function of radiography system by method of step, the errors caused by this method are analyzed. The different degrees on measurement caused by different factors (such as the intersectant degree between the axis and the edge of the step, distance between the axis and the step and the width of the step) are compared in detail. The directive principles on experiment set up for measurement of system SF are derived. Something which may be paid attentions to while carrying out the experiment are also pointed out.更多还原