[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 0U.Ld:  
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。 iztF  
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模型 3%x-^.  
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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。 <X97W\  
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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. (YmIui>  
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光源 FklO#+<:  
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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。 {+9t!'   
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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。 yN
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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。 4tapQgj24  
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视网膜的散射 P[Vf$ q<  
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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。 K~8!Gh{h]  
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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。 !<>`G0  
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脚本 BUsAEwM  
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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： "9H#pj -  
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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。 vmtmiN8;d  
余下的脚本计算与屈光度有关的所有参数。 4-xg+*()  
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分析 Vao3&#D8  
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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。 _3_o/I  
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脚本代码 ?eR^\-e  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. C5#$NV99p  
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Dim entity As T_ENTITY \,b_8^  
Dim op As T_OPERATION \OF"hPq  
Dim mat As T_MODELMATERIAL #!M;4~Sfx  
Dim A As Double mY]R~:  
Dim pupilDiam As Double 4*+)D8  
Dim eID As Long 9KZLlEk5O  
Dim parID As Long > bSQ}kXe  
Dim count As Integer eZRu{`AF*  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double q?Mmkh)g  
Dim tlens As Double, nlens As Double QEq>zuz5;  
Dim curv As Double, conic As Double qVJC O-K|  
Dim ok As Long ep\a  
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Sub Main knu>{a}  
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    '用户输入对话框 +t;j5\HS  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 H52] Zm  
        TextBox 220,21,40,21,.TextBox1 'default: 0 +Tp>3Jh2  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 9xUAf
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        OKButton 40,91,90,21 GV
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        CancelButton 190,91,90,21 PF/eQZ*4  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 {= l9{K`~  
        TextBox 220,49,40,21,.TextBox2 'default: 4 'd=B{7k@  
    End Dialog 5ayH5=(t  
    Dim dlg As UserDialog @{UtS2L  
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    ok = Dialog (dlg) 3+$~l5LY  
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    If ok=0 Then    'cancel button was pressed \*$''`b)j  
        Print "Execution cancelled." |
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        End L(eLxw e%  
    End If Q68q76  
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    'Assign accommodation and pupil diameter & use defaults if field left empty Ucz`^}+  
    If dlg.TextBox1 = "" Then AE 2>smp5@  
        A = 0           'Default accommodation VE5M}kDCZ  
    Else RI jz7ZG  
        A = CDbl(dlg.TextBox1) }zu?SZH  
    End If D>Dch0{H,:  
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    If dlg.TextBox2 = "" Then Kr|9??`0E  
        pupilDiam = 4   'Default pupil diameter J(\f(jh/  
    Else sKI{AHJ?X  
        pupilDiam = CDbl(dlg.TextBox2) oefhJM!y  
    End If 7nAB^~)6l  
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    Print " " BiUbg6T.G  
    Print "Accommodation = " & A & " Diopters" H[&X${ap  
    Print "Pupil Diameter = " & pupilDiam & " mm" 0(!D1G{ul  
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    ' Calculate new parameters with accommodation 8n^v,s>  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness fB3W} dr  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens k&PxhDf  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens RZV6\j  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens [vs5e3B)  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens EpCsJ08K  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 2'zYrdem  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction !yQ#E2/A  
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    'Adjust parameters to account for accommodation Spossp`|  
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    '************************************************************************* ],HF)21  
    'Aqueous thickness (Position of Lens) ~]_gq;bG  
    '************************************************************************* G'sEbw'[  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) W7QcDR y6  
    GetCustomElement eID, entity 3"Y |RSy  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ir%?J&C+t  
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    ' Delete any shift(s) in z [80L|?, *  
    count = 0 B~oc.sg  
    While GetOperationCount(eID)>count 7]w]i5  
        GetOperation eID, count, op pLvvv#Y  
        If op.Type="ShiftZ" Then |Y6+Y{|\  
            DeleteOperation eID,count O*dN+o  
            count=count-1 ersddb^J]  
        End If oyS43/."  
        count=count+1 Bu\:+3)  
    Wend t`6R)'  
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    'Set new shift in \/Z?QBFvz  
    op.Type = "ShiftZ" 7r?s)ZV  
    op.val1 = taq /K{`gc  
    op.parent = parID B1GBQH$Ms  
    AddOperation eID, op 7n,*3;I  
    Print "Set aqueous humor thickness = " & taq-0.55 #G;0yB:76  
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    '************************************************************************* Ungex@s_  
    'Radius and conic constant of anterior lens M~Tx4_t  
    '************************************************************************* c5& _'&  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) QN!$41A?{  
    GetConic eID, entity, curv, conic gn>qd6P  

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    SetConic eID, entity, 1/Rant, CCant 2cy: l03  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant hP1H/=~  
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    '************************************************************************* ^a6c/2K  
    'Radius and conic constant of posterior lens p<w2e  
    '************************************************************************* xWv@PqXD  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) %z}{jqD&:X  
    GetConic eID, entity, curv, conic <g SZt\  
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    SetConic eID, entity, 1/Rpost, CCpost L{py\4z'_  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost +=v6*%y"V  
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    '************************************************************************* :`~;~g
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    'Lens thickness (Position of posterior lens surface) 0=3Av8  
    '************************************************************************* 8Z{e/wnVF  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) .Du-~N4\  
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    ' Delete any z-shift(s) HAof,* h$  
    count = 0 Z%]s+V)st  
    While GetOperationCount(eID)>count 9ZbT41  
        GetOperation eID, count, op r2WW}W  
        If op.Type="ShiftZ" Then gVM&wo |  
            DeleteOperation eID,count 5C}1iZEJ  
            count=count-1 #bz#&vt$  
        End If O_yk<  
        count=count+1 Sm@T/+uG:  
    Wend U}w,$ Y  
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    'Set new z-shift @2>A\0U  
    op.Type = "ShiftZ" [8F1rZ&  
    op.val1 = tlens {tq.c9+!d  
    op.parent = parID C5q n(tv  
    AddOperation eID, op w}wABO  
    Print "Set lens thickness = " & tlens bi^[Eh  
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    '************************************************************************* u0&QStI  
    'Lens index of refraction 8F?6Aq1B  
    '************************************************************************* O] T'\6w  
    eID = FindMaterial( "Lens" ) 3#O Rfr(  
    GetModelMaterial eID, mat eXN\w]GE  
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    mat.Nd = nlens =UGyZV:z5  
    SetModelMaterial eID, mat rD"$,-h  
    Print "Set lens index of refraction = " & nlens 2pKkg>/S  
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    '************************************************************************* MLbmz\8a  
    'Pupil diameter it Byw1/  
    '************************************************************************* P!c.!8C$  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) P2U^%_~  
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    'Adjust pupil diameter (trimming volume inner hole) ;\[n{<   
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" }0Q_yuzx0m  
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    ' Adjust pupil location to just in front of the lens C;mcb$@  
    parID = FindFullName( "Geometry.Arizona Eye" ) Pdq}~um3{  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 8%eWB$<X  
    count = 0 %T~3xQ  
    While GetOperationCount(eID)>count NNOemTh  
        GetOperation eID, count, op T?4pV#  
        If op.Type="ShiftZ" Then mE|?0mRA %  
            DeleteOperation eID,count
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            count=count-1 A_:CGtv:  
        End If Mj9Mv<io  
        count=count+1 3}Xf  
    Wend &xAwk-{W  
    op.Type = "ShiftZ" F'~\
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    op.val1 = taq-0.01 tsYBZaH  
    op.parent = parID Gx&o3^t  
    AddOperation eID, op r
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    Print "Set pupil diameter = " & pupilDiam W 'w{}|  
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    'Update AZ Eye subassembly Description _Se0,Uns  
    eID = FindFullName( "Geometry.Arizona Eye" ) PVCFh$pnw  
    GetEntity eID, entity 9;ZaL7>  
    entity.Description = "Accommodation = " & A & "D" [>IV#6$  
    SetEntity eID, entity ]!um}8!}  
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    Update "j2th.  
    Print "DONE!" [3@Pu.-I+M  
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End Sub ;2k!K
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如果屈光度是4，光瞳直径是4，则会输出如下数据： AGWs>  
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Accommodation = 4 Diopters mqt$'_M  
Pupil Diameter = 4 mm iImy"$yX{  
Set aqueous humor thickness = 2.81 V*Q!J{lj^#  
Set anterior lens radius = 10.4 and conic constant = -2.375869 D&dh>Pe1;  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 >bLhCgF:"  
Set lens thickness = 3.927 {V7W!0;!  
Set lens index of refraction = 1.42672 _HAtTW  
Set pupil diameter = 4 -eQ>3x&3r  
DONE! ^uV=|1<%  
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