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    [转载]FRED运用:Arizona眼睛模型 [复制链接]

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    只看楼主 倒序阅读 楼主  发表于: 2016-02-24
    简介 X|-v0 f  
    人眼光学模型可用来设计眼科用设备,光学系统注定了要与人眼一起使用。本文演示了这样一个模型:Arizona眼睛模型,在Jim Schwiegerling教授的书中有详细描述:《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源,并包括一个基于想要的屈光度来调整模型的内嵌脚本。 fz<|+(_>J  
    V(lK`dY  
    模型 fw:7Q7 qo  
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    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 lnS\5J  
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    Table 1. AZ眼睛模型的定义
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    在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. P EX26==  
    @sB}q 6>  
    光源 Yn IM-  
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    多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 .*RB~c t  
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    图1. 光源和提示信息使用
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    除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 DU/9/ I?~  
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    在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 c ,h.`~{  
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    图2. 字母F光源的设定方法光 ==-7F3QP  
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    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 dl*_ m3T  
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    在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 aJK-O"0/  
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    图4. 视网膜朗伯散射设定
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    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 Z #.GI  
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    图5. 视网膜重点采样规格设定
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    脚本 T!m42EvIvE  
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    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: ^#a#<8Jz  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 #W>x\  
    余下的脚本计算与屈光度有关的所有参数。 &_Cxv8  
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    分析 vbr~<JT=  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 bh=\  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 ]}nu9z<  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. RtW4 n:c  
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    Dim entity As T_ENTITY Nb gp_:{  
    Dim op As T_OPERATION H "Q(2I  
    Dim mat As T_MODELMATERIAL 06PhrPVa!\  
    Dim A As Double C$KaT3I  
    Dim pupilDiam As Double qJ\X~5{  
    Dim eID As Long iP~sft6  
    Dim parID As Long I?f"<5[0  
    Dim count As Integer !&@2  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double CMC?R,d  
    Dim tlens As Double, nlens As Double D"`%|`O  
    Dim curv As Double, conic As Double -(6eVI  
    Dim ok As Long >=4sPF)  
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    Sub Main b0r,h)R  
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        '用户输入对话框 <$"7~i /X  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 b2a'KczV  
            TextBox 220,21,40,21,.TextBox1 'default: 0 }=Hf?';m  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Sv.KI{;v$  
            OKButton 40,91,90,21 r`?&m3IOP  
            CancelButton 190,91,90,21 E2>im>p  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 vad|Rpl  
            TextBox 220,49,40,21,.TextBox2 'default: 4 %0NLRfp  
        End Dialog F?!FD>L{`  
        Dim dlg As UserDialog 8r2XGR  
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        ok = Dialog (dlg) !?yxh/>lM  
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        If ok=0 Then    'cancel button was pressed 4#TnXxL  
            Print "Execution cancelled." eT;AAGql  
            End ;_x2 Ymw  
        End If t$aVe"uM  
    7 2`/d`  
        'Assign accommodation and pupil diameter & use defaults if field left empty G?>qd}]y0L  
        If dlg.TextBox1 = "" Then |d5ggf .w  
            A = 0           'Default accommodation CP}0Ri)  
        Else Q?W r7  
            A = CDbl(dlg.TextBox1) P~&O4['<  
        End If Gj6<s./  
    7^HpVcSM  
        If dlg.TextBox2 = "" Then x]H3Y3  
            pupilDiam = 4   'Default pupil diameter yxqTm%?y  
        Else QT_Srw@  
            pupilDiam = CDbl(dlg.TextBox2) Xe)Pg)J1  
        End If bC6X?m=  
    QDP-E[  
        Print " " VIetcs  
        Print "Accommodation = " & A & " Diopters" y*_K=}pk  
        Print "Pupil Diameter = " & pupilDiam & " mm" '=$TyiU  
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        ' Calculate new parameters with accommodation x 96}#0'  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness xOhRTxic  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens ;.\g-`jb  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ACgt" M.3F  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens (WJV.GcP1  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens X!o@f$  
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        tlens = 3.767 + 0.04*A                  'Lens thickness eVTO#R*'|  
    [;<<4k(nL  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction cY{I:MA+h@  
    ;jF%bE3  
        'Adjust parameters to account for accommodation <8$Md4r  
    c$/<l5Uw  
        '************************************************************************* P> |Ef~j  
        'Aqueous thickness (Position of Lens) >;m{{nj  
        '************************************************************************* ^[0" vtb  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) V w7WK  
        GetCustomElement eID, entity iW'_R{)T  
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        parID = FindFullName( "Geometry.Arizona Eye" ) QJQJR/g  
    $-Cy  
        ' Delete any shift(s) in z _n7%df  
        count = 0 rj}(muM,R  
        While GetOperationCount(eID)>count FbmsN)mv!%  
            GetOperation eID, count, op m!;G/s*  
            If op.Type="ShiftZ" Then _$!`VA%  
                DeleteOperation eID,count *aI~W^N3  
                count=count-1 J, r Xx:  
            End If ]/a g*F  
            count=count+1 }H5/3be  
        Wend _;#9!"&  
    _nP)uU$  
        'Set new shift in {b[tA, >  
        op.Type = "ShiftZ" <vL}l:r  
        op.val1 = taq ghX:"vV{n  
        op.parent = parID .3(;9};  
        AddOperation eID, op l`* ( f9Q  
        Print "Set aqueous humor thickness = " & taq-0.55 Xh`"  
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        '************************************************************************* pG~'shD~Dn  
        'Radius and conic constant of anterior lens 4AuH1m)<  
        '************************************************************************* w?*j dwh,'  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) db'K!M)  
        GetConic eID, entity, curv, conic eJW[ ]!  
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        SetConic eID, entity, 1/Rant, CCant Fk aXA.JE  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant UP?D@ogl<  
    tR5tPPw  
        '************************************************************************* 6A.P6DW  
        'Radius and conic constant of posterior lens >r=6A   
        '*************************************************************************  J+lGh9G  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) z$66\/V']  
        GetConic eID, entity, curv, conic T30Zk*V  
    ldYeX+J _  
        SetConic eID, entity, 1/Rpost, CCpost svqvG7  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost Nkx0CG*  
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        '************************************************************************* s+'XQs^{aj  
        'Lens thickness (Position of posterior lens surface) ,&[7u9@  
        '************************************************************************* i_NJ -K  
    #%4=)M>^  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ]H>+m 9  
    ![).zi+m  
        ' Delete any z-shift(s) z|Ap\[GS  
        count = 0 R2CQXhiJ  
        While GetOperationCount(eID)>count ?d~]Wd!z  
            GetOperation eID, count, op z(rK^RT  
            If op.Type="ShiftZ" Then >IBTBh_ka  
                DeleteOperation eID,count F(;jM(  
                count=count-1 l 1|~  
            End If #cO+<1  
            count=count+1 /z#F,NB  
        Wend ld95[cTP  
    mbGcDG[HQ  
        'Set new z-shift TOrMXcn!/  
        op.Type = "ShiftZ" _F^$aZt?e  
        op.val1 = tlens McP~}"!^  
        op.parent = parID Li]k7w?H  
        AddOperation eID, op 6< >SHw  
        Print "Set lens thickness = " & tlens Co[n--@C  
    TW2Z=ks=  
        '************************************************************************* DRp&IP<  
        'Lens index of refraction ZL=N[XW4'  
        '************************************************************************* +YuzpuxjJ  
        eID = FindMaterial( "Lens" ) M!#AfIyB  
        GetModelMaterial eID, mat wA631kr  
    2kVp_=c  
        mat.Nd = nlens @C=M UT-!  
        SetModelMaterial eID, mat XGhwrI^  
        Print "Set lens index of refraction = " & nlens 7 v~ro  
    ^aHh{BQ%  
        '************************************************************************* QLn+R(r  
        'Pupil diameter Je@kiE  
        '************************************************************************* L1{T ?aII  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) rn H}#u+  
    _YLUS$Zw  
        'Adjust pupil diameter (trimming volume inner hole) r6MB"4xd  
    D^|7#b,zcH  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 9x[ U$B  
    xDUaHE1co  
        ' Adjust pupil location to just in front of the lens 1 }nm2h1 I  
        parID = FindFullName( "Geometry.Arizona Eye" ) B4^`Sw  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 79wLT \&  
        count = 0 U!0E_J  
        While GetOperationCount(eID)>count hiN/S|JN8y  
            GetOperation eID, count, op BGzO!s*@j  
            If op.Type="ShiftZ" Then ?@DNsVwb  
                DeleteOperation eID,count [@|be.g  
                count=count-1 Cg3ODfe  
            End If qv uxhzF  
            count=count+1 `m, Ki69.  
        Wend q]XHa,"  
        op.Type = "ShiftZ" A9;0y jae  
        op.val1 = taq-0.01 ;cLUnsB\  
        op.parent = parID K$ AB} Fvc  
        AddOperation eID, op iadkH]w  
    !oGQ8 e  
        Print "Set pupil diameter = " & pupilDiam ]u0Jd#@  
    #w*"qn#2Uz  
        'Update AZ Eye subassembly Description i-.c= M  
        eID = FindFullName( "Geometry.Arizona Eye" ) c3#q0Ma  
        GetEntity eID, entity e9:P9Di(b  
        entity.Description = "Accommodation = " & A & "D" ]"h=Qc  
        SetEntity eID, entity (bvoF5%  
    Hk9U&j$  
        Update AerFgQiS  
        Print "DONE!" @[v8}D  
         OpQ8\[X+  
    End Sub %t[K36,p  
    {(Fe7,.S3  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: vYdlSe=6G  
    |!}wF}iLc)  
    Accommodation = 4 Diopters :1MM a6  
    Pupil Diameter = 4 mm c3W BALdh  
    Set aqueous humor thickness = 2.81 kc Y,vl  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ]7vf#1i<  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 $:;%bjSI  
    Set lens thickness = 3.927 Bm} iU~(Z`  
    Set lens index of refraction = 1.42672 `< Yf{'*  
    Set pupil diameter = 4 mgcN(n1  
    DONE! q% E C  
    TGpSulg7  
    (文章来源:讯技光电)
     
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