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20079223()JournalofShandongNormalUniversity(NaturalScience)Sep.2007Vol.22No.3张燕1),2)刘轩3)(1),250014,;2),250109,;3),250101,M26,,),,.,,,.,,,,;,;.;;;O438.1,,.,(,1CCDCMOS),,,.,[1~2][3~5][6][7].1,.,uc(x,y),uc(mDx,nDy)=uc(x,y)comb(xPDx,yPDy)rect(xP2Lx,yP2Ly),(1)comb(xPDx,yPDy),rect(xP2Lx,yP2Ly),DxDy,Lx=MDxP2,Ly=NDyP2,m,n,M,N.IH,uH(mDx,nDy)=IH(mDx,nDy)uc(mDx,nDy).(2)1.1,z,u(x,y)=uH(x,y)*h(x,y)u(mDx,nDy)=uH(mDx,nDy)*h(mDx,nDy),(3)/*0,h(x,y)=exp(jkz)jKzexpjPKz(x2+y2)ejkzjKzexpjk2z[(mDx)2+(nDy)2],(4)(3)u(mDx,nDy)=IDFT{DFT[uH(mDx,nDy)]DFT[h(mDx,nDy)]}.(5)1.2,z,U(pDN,qDG)=DFT[uH(mDx,nDy)]H(pDN,qDG)(DN=1PMDx,DG=1PNDy),(6)H(N,G)=exp[j2Pz(1PK2)N2-G2]exp[j2Pz1PK2-(pDN)2-(qDG)2],(7)(6)u(mDx,nDy)=IDFT{DFT[uH(mDx,nDy)]H(pDN,qDG)}.(8)1.3,u(x,y)=ejkzjKzk]-]uH(xH,yH)expjk2z[(x-xH)2+(y-yH)2]dxHdyH.(9),(9)uH(xH,yH)exp[jk(x2+y2)P2z],u(pDN,qDG)=Cexp[jPKz(p2DN2+q2DG2)]DFTuH(mDx,nDy)expjk2z(m2Dx2+n2Dy2,(10)C.(10)u(pDxc,qDyc)=CexpjPKz(p2Dxc2+q2Dyc2)DFTuH(mDx,nDy)expjk2z(m2Dx2+n2Dy2,(11):2007-01-08:DN=DxcPKz=1PMDx,DG=DycPKz=1PNDy.,.,:Dx=KzPM,Dy=KzPN.2g(x,y)=expjPKz(x2+y2)rectx2LXrecty2Ly,(12)Nl=(1P2P#9P9x)(x,y),Gl=(1P2P#9P9y)(x,y),Nl=(xPKz)rect(xP2Lx),Gl=(yPKz)rect(yP2Ly),Nlm=LxPKz=Bx,Glm=LyPKz=By.Dx[1P2Bx=KzP2Lx,Dy[1P2By=KzP2Ly,z\2DxLxPK=MDx2PK,z\2DyLyPK=NDy2PK.H(p,q)=exp(jkz)exp[-jPKz(N2+G2)],(13)Nl=KzNrect(NP2LN),G1=KzGrect(GP2LG)Nlm=KzLN=BN,Glm=KzLG=BG,DN=1PMDx[1P2KzLN,DG=1PNDy[qP2KzLG,z[MDxP2KLN=MD2PK,z[NDyP2KLG=NDy2PK.3,.,512@512.,200mm60mm81mm,10Lm@10Lm,0.6328Lm,..,,.1.,zMDx2PK,;zMDx2PK,;z=MDx2PK,.1(a1)(a2)(a3)200mm;(b1)(b2)(b3)60mm;(c1)(c2)(c3)81mm4,,;;,,,.48()225[1]YamaguchiJ,KatoS.Imageformationinphase-shiftingdigitalholographyandapplicationonmicroscopy[J].AppliedOptics,2001,40(34):6177~6186[2],,,.[J].#,2005,16(2):226~230[3],.[J].,2004,33(2):171~173[4]CucheE,MarquetP,DepeursingeC.Simultaneousamplitude-contrastandquantitativephase-contrastmicroscopybynumericalreconstructionofFresneloff-axisholograms[J].AppliedOptics,1999,38(34):6994~7001[5],,.[J].(),2006,26(1):62~64[6],,,.[J].,2003,33(9):823~828[7]LaiS,NeifeldMA.Digitalwavefrontreconstructionanditsapplicationtoimageencryption[J].OptCommunications,2000,178(4):283~289COMPARISONOFDIGITALRECONSTRUCTIONMETHODSOFFRESNELHOLOGRAMZhangYan1),2)LiuXuan3)(1)CollegeofPhysicsandElectronics,ShandongNormalUniversity,250014,Jinan,China;2)ShandongXieheUniversity,250109,Jinan,China;3)CollegeofScience,ShandongJianzhuUniversity,250101,Jinan,China)AbstractThreecomputersimulatedalgorithmsofFresneldiffractionintegralareanalyzedindetailbasedonscalardiffractiontheoryandfastFouriertransform.ThesethreealgorithmsareappliedindigitalreconstructionprogramforFresnelholograms.Theoreticalanalysisprovesthat,whenthepixelnumber,pixelsizeandreconstructedwavelengthofthehologramarecertain,computersimulatedalgorithmsofFresneldiffractionintegralfallintoconvolutionalgorithm,angularspectrumalgorithmanddirectFouriertransformalgorithmaccordingtothedifferenceofthesampledobject.Byanalyzingthelocalspatialfrequenceofphasefunction,aproperreconstructeddistanceusedtodeterninetheapplicablerangeofthreealgorithmsisobtained.Andaboveanalysisindicatedthefollowingresults:ifthereconstructeddistanceislargerthanproperreconstructeddistance,convolutionalgorithmisthebestalgorithms;ifreconstructeddistanceislessthanproperreconstructeddistance,angularalgorithmisthebestalgorithmsifreconstructeddistanceisequaltoproperreconstructeddistance,allthreealgorithmsaresuitable.Keywordsconvolutionalgorithm;angularspectrum;directFouriertransformalgorithm;Fresnelhologram493,: