Gabor同轴数字全息的多重再现与自动聚焦  

Multi-Plane Reconstruction and Auto-Focus Method of Gabor In-Line Digital Holography

作　　者：刘迪[1] 王玉荣[1] 孟祥锋[1] 杨修伦[1] 王青圃[1] 

机构地区：[1]山东大学信息科学与工程学院山东省激光技术与应用重点实验室,山东济南250100

出　　处：《中国激光》2014年第9期230-238,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(61275014);山东省科技计划(2011GGH20119);山东省自然科学基金(ZR2011FQ011)

摘　　要：对于近场同轴数字全息在聚焦再现(再现距离精确等于实际记录距离)时,采用多重再现方法可以很好地消除共轭像的影响,但该方法没有考虑和分析再现距离与实际记录距离存在偏差时的影响。然而在实际应用中,实际记录距离难于精确测定,数字再现时采用的再现距离往往与实际记录距离存在偏差。对该方法进行了进一步的深入分析,分析发现该方法对距离偏差十分敏感,且随着距离偏差增大其共轭像消除效果会急剧下降;利用该方法对距离偏差的敏感特性,可以提高同轴数字全息自动聚焦的精准性和灵敏性。对上述结论进行了原理分析和实验验证。For the near-field in-line digital holography,the multi-plane reconstruction method used to eliminate the twin image works well when the reconstructing distance is exactly equal to the actual recording distance.However,it does not consider and analyze the influence when there is a deviation between the two distances.In practice,it is difficult to accurately measure the actual recording distance,and the deviation between the reconstructing distance and the actual recording distance always exist in the digital reproduction.A thoughtful analysis for this method is presented and it is found that this method is very sensitive to the distance deviation,and as the deviation increases its efficiency and effectiveness will be greatly decreased.The distance deviation sensitivity of this method can be used to improve the autofocus accuracy and sensibility in the reconstruction of Gabor in-line digital holography.Principle analysis and experimental verification confirm the above conclusions.

关 键 词：全息 同轴数字全息 Gabor同轴数字全息 聚焦函数 自动聚焦 

分 类 号：O436[机械工程—光学工程]