在光极位置的不确定性对自校准或双斜扩散光学测量的影响
Giles Blaney1, Angelo Sassaroli1, Tapan Das2
1Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford MA 02155, USA.
概括
精确的光极定位对于扩散光学测量至关重要. 源和探测器位置的小误差对散射测量有显著的影响,而不是吸收,特别是对于绝对值.
科学领域:
- 分散光学
- 生物医学光学
- 光子学
背景情况:
- 自校准和双倾斜测量对于评估生物组织等散射介质的光学特性至关重要.
- 这些技术使用多个源和探测器位置的光学探测器进行可靠的测量.
- 准确评估绝对值和时间变化依赖于精确的探头几何.
研究的目的:
- 量化分析源和探测器位置错误对光学性能评估的影响.
- 评估光极定位的不确定性对散射和吸收系数的影响.
- 为提高测量精度,确定最佳的光极安排和误差宽容度.
主要方法:
- 基于半无限同质介质的扩散理论的理论计算.
- 线性,梯形和矩形 optode 安排的分析.
- 模拟源和探测器的位置不确定性.
主要成果:
- 在绝对测量中,光极位置的不确定性对散射系数的影响大于吸收系数.
- 在线排列中的1mm位移可以导致吸收的平均误差为4.1%,散射的平均误差为19%.
- 与绝对值相比,位置错误对吸收变化的测量影响较小.
结论:
- 精确的光极定位对于精确的扩散光学测量至关重要,特别是对于散射系数.
- 了解位置错误的影响有助于设计更强大的光学探测器.
- 优化 optode 几何学可以最大限度地降低自校准和双斜率系统的测量不确定性.
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