Analytic Derivation and Monte Carlo Validation of a Sensitivity Formula for Slit-Slit Collimation With Penetration.
Analytic Derivation and Monte Carlo Validation of a Sensitivity Formula for Slit-Slit Collimation With Penetration.
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狭缝-狭缝穿透准直灵敏度公式的解析推导和蒙特卡罗验证。
DOI：
10.1109/tns.2009.2030580
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发表时间：
2010
影响因子：
1.8
通讯作者：
Accorsi,Roberto
中科院分区：
文献类型：
--
作者：
Ayan,AhmetS;Metzler,ScottD;Accorsi,Roberto
狭缝准直器由两个正交狭缝组成，可以概念化为广义的针孔。由于两个狭缝彼此独立，因此可以有独立的轴向和横轴接受角。小的轴向接受角可能有助于减轻圆形轨道的轴向模糊，从而允许轴向多个副本。此外，由于两个狭缝平面可以放置在相对于源的不同距离处，因此可以实现更好的探测器使用，特别是在探测器和成像物体具有不同纵横比的情况下。在本文中，推导了狭缝-狭缝准直灵敏度的解析表达式，包括光子穿透的有效狭缝宽度。为了准确地模拟系统响应，需要灵敏度的解析表达式。该表达式还可用于比较狭缝-狭缝与其他狭缝的灵敏度性能。当使用有效狭缝宽度而不是几何狭缝宽度时，导出的解析表达式准确地解释了孔径的光子穿透。导出的灵敏度表达式通过蒙特卡罗模拟对几何和穿透情况进行了验证。
A slit-slit collimator consists of two orthogonal slits and can be conceptualized as a generalized pinhole. Since the two slits are independent of each other, there can be independent axial and transaxial acceptance angles. A small axial acceptance angle may help mitigate axial blurring with circular orbits, allowing multiple copies axially. In addition, since the two slit planes can be placed at different distances with respect to the source, a better detector usage can be achieved, especially in the case of detectors and imaged objects with different aspect ratios. In this paper, an analytical expression is derived for the sensitivity of slit-slit collimation including effective slit widths for photon penetration. An analytical expression for sensitivity is necessary in order to accurately model the system response. This expression could also be useful for comparing a slit-slit's sensitivity performance with others. When the effective slit width is used instead of the geometric slit width, the derived analytical expression accurately accounts for photon penetration of the aperture. The derived expression for the sensitivity was validated by Monte Carlo simulation for both geometric and penetrative cases.