菲涅耳数字全息成像系统的焦深  

Focal Depth of Fresnel Digital Holographic Imaging System

作　　者：王华英[1] 赵宝群[1] 宋修法[1] 

机构地区：[1]河北工程大学理学院,河北邯郸056038

出　　处：《光学学报》2009年第2期374-377,共4页Acta Optica Sinica

基　　金：国家自然科学基金(60577029);河北省自然科学基金(F2008000750)资助课题

摘　　要：焦深是表征成像系统性能的重要参数。基于透镜相干成像的焦深判据,利用数值积分和计算机模拟的方法,分析和推导了菲涅耳数字全息成像系统的焦深,给出了相应的焦深表达式.并与利用理想成像四分之一波像差的判据得到的焦深进行了比较。结果表明:菲涅耳数字全息成像系统的焦深不同于透镜相干成像系统的焦深。在记录距离和CCD参数一定的条件下,离轴菲涅耳数字全息成像系统的焦深略大于同轴菲涅耳数字全息的焦深;离轴对称偏置情况下的焦深略大于非对称情况下的焦深。利用像强度判据得到的焦深,能够较好地表征数字全息成像系统的性能。Depth of focal （DOF） is an important parameter characterizing the performance of imaging system. Based on the criterion of the DOF of coherent lens imaging and by using numerical integration and computer simulations, the DOF of Fresnel digital holographic imaging system is deduced and analyzed. The corresponding expressions are compared with that obtained by the phase error criterion of ideal imaging. The results show that the DOF of Fresnel digital holographic system is different from that of coherent lens imaging system. Withthe definite recording distance and definite parameters of CCD, the DOF of off-axis Fresnel system is slightly larger than that of in-line system. Furthermore, the DOF of off-axis system with symmetrical reference offset is larger than that of the unsymmetrical one a little. The DOF obtained by image intensity criterion can be better characterized the performance of digital holographic imaging system.

关 键 词：全息 菲涅耳数字全息 数字全息术 焦深 焦点公差 

分 类 号：O438.1[机械工程—光学工程]