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阶段偏移方法的图形对比逆转校正的相位偏移方法.
Christoph Hofer1, Chuang Gao1, Tamazouzt Chennit1
1EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium; NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
Ultramicroscopy
|January 13, 2024
概括
单侧带 (SSB) 图形学可以由于相环形异步,逆转对比度. 一种新的相位偏移方法有效地抵消了这些反转,改善了各种样本厚度的图像解释性.
科学领域:
- 电子显微镜的电子显微镜
- 材料科学是一种材料科学.
- 图像技术的成像技术.
背景情况:
- 像单侧带 (SSB) 这样的直接图形学方法,经常表现出单签名对比传递函数.
- 在SSB图解学中可以发生对比逆转,特别是在强大的投射潜力或更厚的样本中.
- 中心聚焦通常用于减轻较厚样本中的对比度问题,但它可以降低环状暗场 (ADF) 信号的质量.
研究的目的:
- 为了调查SSB图解学中对比度逆转的原因.
- 引入和评估一种新的相位偏移方法来抵消对比度逆转.
- 为了证明相位偏移方法比收集后失焦校正的优势.
主要方法:
- 在SSB ptychography的频率响应中分析阶段包裹异常点.
- 开发一种相位操纵技术,以转移或减轻这些非对应点.
- 拟议的相位偏移方法与采集后失焦校正的比较.
主要成果:
- 在SSB ptychography的频率响应中,相包裹异位被确定为对比逆转的原因,独立于动态散射.
- 引入的相位偏移方法有效地通过操纵相位对称来对抗对比逆转.
- 相比于采集后失焦校正,相位偏移方法显示出更高的可靠性和对比度.
- 这种方法对薄型和厚型样品都有效,与中央聚焦不同.
结论:
- 在SSB图解学中,对比度的反转是由于相环异位而产生的,并且可以通过相位操纵来纠正.
- 新的相位偏移方法为纠正对比逆转提供了一种更优质,更可靠的方法.
- 阶段偏移方法的焦点独立性增强了其用于光学切割和样本分析的实用性.
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