中国计量大学计量测试工程学院, 浙江 杭州 310018
为了解决数字全息中子孔径相位拼接的效率和精度问题,提出了数字全息中基于多算法融合优化的相位拼接方法来实现相位的双方向拼接。首先,在相位拼接中选用相位相关法确定重叠区域,以限定特征点检测和提取范围,从而提升特征点检测的速率和有效特征点检测的占比;然后,对重叠区域进行Harris角点检测和角点匹配,并根据角点匹配点对来缩小块匹配算法的搜索范围;最后,采用全匹配搜索算法对最佳角点匹配点对进行精确匹配,并通过加权融合实现三维形貌的再现相位拼接。实验结果表明,本文算法能够在保证较高的拼接精度的情况下,极大地提高相位拼接的效率。
1 中国计量大学 计量测试工程学院, 浙江 杭州 310018
2 桂林电子科技大学 广西光电信息处理重点实验室培育基地, 广西 桂林 541004
3 青岛市计量技术研究院, 山东 青岛 266100
针对数字全息技术中测量面积受限的问题, 提出基于优化Harris角点算法的拼接算法实现相位的双方向拼接。在获取数字全息图像时, 保证相邻区域具有部分重叠, 再对获得的物体的各子孔径相位图像进行拼接; 用Harris角点算法检测角点密集区域为匹配模板, 可高效且精准地确定重叠区域, 结合高斯尺度空间和金字塔匹配思想对算法进行优化, 通过加权融合实现三维形貌的再现相位拼接。以玻璃样板为实验对象, 完成了物体再现相位的双方向拼接。实验结果表明: 该拼接方法能够有效扩大数字全息测量物体的测量面积, 并保证了较高的拼接准确度。
数字全息 Harris角点算法 高斯尺度空间 相位拼接 digital holography Harris corner algorithm Gaussian scale space phase splicing 红外与激光工程
2019, 48(11): 1126002
Author Affiliations
Abstract
Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Laboratory of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049, China
We study the parametric amplification of electromagnetically induced transparency-assisted Rydberg six- and eight-wave mixing signals through a cascaded nonlinear optical process in a hot rubidium atomic ensemble both theoretically and experimentally. The shift of the resonant frequency (induced by the Rydberg–Rydberg interaction) of parametrically amplified six-wave mixing signal is observed. Moreover, the interplays between the dressing effects and Rydberg–Rydberg interactions in parametrically amplified multiwave mixing signals are investigated. The linear amplification of Rydberg multiwave mixing processes with multichannel nature acts against the suppression caused by Rydberg–Rydberg interaction and dressing effect.
Rydberg states Nonlinear wave mixing Nonlinear optics, four-wave mixing Nonlinear optics, parametric processes Photonics Research
2018, 6(7): 07000713
