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1、菲涅耳全息图的编码与显示摘要普通显示技术是根据几何光学成像原理,记录下光波的振幅,将空间物体成像在一个平面上。由于丢失了光波的相位信息,因而物体的信息是不完整的。全息图因能够完整地记录物光波的振幅和相位,因而能够包含物体的全部信息。菲涅耳全息术作为全息术的一个分支,更是得到了飞速的发展,已经广泛应用于全息干涉计量术、全息存储、全息光学组件、全息显微术等各个领域。本论文主要研究菲涅耳全息图的编码与显示过程。经典光全息术包括波前记录和波前再现两步。全息波前记录将物光和参考光以干涉条纹记录成全息图,此全息图同时记录了物光波的振幅和相位;然后用参考光照射全息图,该参考光经过衍射
2、后,即可再现出原始物体。计算全息是将先进的计算机技术和光全息术结合起来,利用计算机产生全息图。它不需要物体实际存在,而是把物波的数学描述输入计算机处理后,绘制出全息图,然后用光学方法重现。本文采用计算全息方法,利用Matlab模拟光线的菲涅耳衍射传播,用计算机生成菲涅耳全息图,并由所生成的全息图再现出原始图像,完成全息图的数字再现。关键词:物光波;菲涅耳衍射;计算全息;计算机模拟FresnelhologramcodinganddisplayAbstractCommondisplaytechnologyisbasedongeometricalopticaltheory,t
3、heamplitudeofwavesrecorded,thespaceobjectimaginginaplane.Becausethephaseinformationoflightislost,theobjectinformationisincomplete.Hologramcanrecordtheamplitudeandphaseofobjectwavescompletely,soitcancontainalltheinformationoftheobject.Fresnelholographyasabranchofholography,itishasmaderapi
4、ddevelopment,hasbeenwidelyusedinholographicinterferometer,holographicstorage,holographicopticalcomponents,holographicmicroscopy,andotherfields.Inthispaper,thekeypointisthecodinganddisplayprocessesofFresnelhologram.Classicalopticalholographyincludestwostepsofwave-frontrecordingandreconstr
5、uctionofwavefront.Theholographicrecordingrecordtheobjectwavesandreferencelightinahologrambytheformofinterferencefringes,thehologramhaverecordedtheinformationoftheamplitudeandphaseofobjectwaves;thenuesingreferencebeamirradiatinghologram,bydiffraction,originalobjectcanbereconstructed.Compu
6、ter-GeneratedHologram(CGH)isthetechnologywhichcombinesadvancedcomputertechnologyandopticalholography,andgeneratinghologramsbycomputers.Itdoesnotrequiretheactualexistenceofobjects,onlyneedsthemathematicaldescriptionoftheobjectwavetoinputthecomputerforprocessing,thendrawingoutthehologram,a
7、tlastusingopticalmethodstoreconstructoriginalobject.Inthispaper,withthemethodofCGH,FresnelhologramisgeneratedbyMatlabincomputer,thenoriginalimageisreconstructedbythehologram,thusdigitalreconstructionofhologramiscompleted.Keywords:objectwaves;fresneldiffraction;CGH;compute