概括
编码孔径成像通过解码探测器信号来重建源. 孔口和探测器之间的旋转错位是高度敏感的,导致人工物,特别是在小型探测器.
科学领域:
- 光学和成像技术的发展
- 射线和中子成像X射线和中子成像
- 图像重建 图像的重建
背景情况:
- 编码光圈成像是一种无镜头技术,用于提高低流量或高分辨率成像的信号强度.
- 重建涉及卷曲探测器数据与光圈图案,以获得点传播函数 (PSF).
- 一个干净的PSF在理想情况下类似于迪拉克三角函数,没有文物.
研究的目的:
- 为了检查编码的光圈解码对实验性公差的稳定性.
- 为了分析重建的PSF中由于放大,旋转和探测器大小等变化的工件生长.
- 将理论预测与实验测量进行比较.
主要方法:
- 在不同的实验条件下对重建的PSF中人工物生长的分析.
- 错误的放大,旋转和探测器大小所带来的影响的插图.
- 在中子成像设施使用编码光圈进行实验性PSF测量.
主要成果:
- 孔径探测器旋转错位是最敏感的参数,导致具有小度偏移的工件.
- 小型探测器尺寸导致无法补偿的文物生成.
- 实验性PSF测量使用与中子源编码的光圈进行.
结论:
- 在样本不足的制度中,建议放大编码孔径,以更好地表征偏移.
- 信任标记可以帮助描述光圈探测器旋转偏移.
- 机械合可以限制旋转和放大偏移,以提高重建保真度.
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