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| 基于小波变换的太赫兹数字全息成像自动聚焦算法 | |
| 引用本文： | 薛凯,李琦,王骐.基于小波变换的太赫兹数字全息成像自动聚焦算法[J].中国激光,2012,39(s1):111005. |
| 作者姓名： | 薛凯 李琦 王骐 |
| 作者单位： | 薛凯:哈尔滨工业大学可调谐激光技术国家级重点实验室， 黑龙江 哈尔滨 150081 李琦:哈尔滨工业大学可调谐激光技术国家级重点实验室， 黑龙江 哈尔滨 150081 王骐:哈尔滨工业大学可调谐激光技术国家级重点实验室， 黑龙江 哈尔滨 150081 |
| 基金项目： | 高等学校博士学科点专项科研基金(20112302110028)资助课题。 |
| 摘 要： | 自动聚焦技术是实现数字全息成像快速、准确再现的关键技术之一。在分析聚焦和离焦过程中小波变换高频和低频系数变化特点的基础上，提出了一种基于小波变换的聚焦判据函数。采用无噪声和被噪声污染的模拟太赫兹(THz)数字全息图，比较分析了这种聚焦判据函数和五种经典的数字全息聚焦判据函数的性能，给出了综合评价。仿真结果表明：同五种经典聚焦判据函数相比，基于小波变换的聚焦评价函数具有更好的单峰性、更高的主峰锐度和极佳的抗噪性，是一种性能优越的THz数字全息成像自动聚焦判据函数。 |
| 关 键 词： | 数字全息 聚焦函数 自动聚焦 小波变换 |
| 收稿时间： | 2012/1/5 |
Wavelet-Based Autofocus Algorithm for Terahertz Digital Holographic Imaging |
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| Abstract: | Autofocus technique is one of the key techniques in digital hologram, which can achieve fast imagine capture and accurate reconstruction. A new wavelet-based autofocus algorithm for terahertz (THz) digital holographic imaging is proposed based on the analysis of focus and defocus characteristics, which mainly concentrates on coefficient of high frequency and low frequency wavelet transform. The new autofocus algorithm of this focus measure is compared with five classic digital hologram autofocus algorithms according to the THz image with and without noise, also comments are attached. The analysis and comparison of the simulation show that the new wavelet-based autofocus algorithm has the following features: a better unimodality, a fineness sharpness and a stronger performance of anti-noise. |
| Keywords: | digital holography focus algorithm autofocusing wavelet transform |