Fiber-optic fan-beam absorption tomography.
Fiber-optic fan-beam absorption tomography.
复制标题
光纤扇形束吸收断层扫描。
作者：
E. Beiting
描述了一种吸收断层扫描仪器，该仪器能够在不到 200 ns 的时间内获取 100 个元素的 100 个投影。该仪器使用时分复用光纤扇形光束源，这些源按组顺序激活，以大大减少实现给定分辨率所需的探测器总数。介绍了根据特定应用定制该仪器所需的定量细节。使用单光纤原型来验证设计并确定其灵敏度。灵敏度受到激光散斑噪声的限制。光纤扇形光束发生器可以产生投影噪声的探测器间相关性，从而减少该噪声对重建的影响。噪声测量为光纤稳定性和尺寸、激光带宽和模式稳定性以及探测器尺寸的函数。
An absorption tomography instrument that is capable of acquiring 100 projections of 100 elements each in less than 200 ns is described. The instrument uses time-multiplexed, fiber-optic fan-beam sources that are sequentially activated in groups to reduce greatly the total number of detectors required for achieving a given resolution. The quantitative details required to tailor this instrument to a particular application are presented. A single-fiber prototype was used to verify the design and establish its sensitivity. The sensitivity is limited by laser-speckle noise. The fiber-optic fan-beam generator can produce an interdetector correlation of the projection noise, reducing the effect of this noise on the reconstruction. The noise is measured as a function of optic-fiber stability and size, laser bandwidth and mode stability, and detector size.