[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 wu3p2#-Z  
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。 IJBIO>Z/  
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模型 Muok">#3.  
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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。 -o+; e3#  
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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. s} oD?h:T3  
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光源 Q+dLWFI  
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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。 R_Uy.0=4  
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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。 c"pu"t@/Z  
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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。 I~ e,']  
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视网膜的散射 H
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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。 U<wM#l P|Z  
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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。 98lz2d/Fcq  
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脚本 KdC'#$  
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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： B[fbPrM  
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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。 z|O3pQn~  
余下的脚本计算与屈光度有关的所有参数。 $8>II0C.  
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分析 6@I
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 HH|N~pBJB  
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脚本代码 NB3ar&.$S  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. )jm!^m  
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Dim entity As T_ENTITY !nTI(--  
Dim op As T_OPERATION \ `|  
Dim mat As T_MODELMATERIAL U$LI~XZM  
Dim A As Double 4f'!,Q ;  
Dim pupilDiam As Double ~xf uq{L;  
Dim eID As Long jz,Gj}3;  
Dim parID As Long Pp`[E/ qj4  
Dim count As Integer TsY nsLQY  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double $.3J1DU  
Dim tlens As Double, nlens As Double dlBr2 9  
Dim curv As Double, conic As Double co{i~['u  
Dim ok As Long r}-vOPn`E  
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Sub Main HEm XB=  
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    '用户输入对话框 p']{WLDj2  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 j9&x#U  
        TextBox 220,21,40,21,.TextBox1 'default: 0 u^( s0q  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 t(xe*xS  
        OKButton 40,91,90,21 Xr{ r&Rl  
        CancelButton 190,91,90,21 lF~!F<^9  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 s,-}}6WO  
        TextBox 220,49,40,21,.TextBox2 'default: 4 >Zh^,T={G  
    End Dialog B* k|NZj  
    Dim dlg As UserDialog lf_q6y  
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    ok = Dialog (dlg) wQojmmQ  
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    If ok=0 Then    'cancel button was pressed `: 9n ]xP  
        Print "Execution cancelled." Vn?|\3KY  
        End pd.5  
    End If aEdc8
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    'Assign accommodation and pupil diameter & use defaults if field left empty Dw.Pv)'$  
    If dlg.TextBox1 = "" Then )|KZGr  
        A = 0           'Default accommodation fkD-mRKw
  
    Else `h<>_zpjY  
        A = CDbl(dlg.TextBox1) LXm@h  
    End If cX|(/h,W/  
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    If dlg.TextBox2 = "" Then 7x.] 9J  
        pupilDiam = 4   'Default pupil diameter '3 JVUHn  
    Else @-.Tgpe@a  
        pupilDiam = CDbl(dlg.TextBox2) '%*/iH6<U{  
    End If D{^CJ :n  
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    Print " " 6<No_x |_  
    Print "Accommodation = " & A & " Diopters" Za7!n{?0  
    Print "Pupil Diameter = " & pupilDiam & " mm" 
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    ' Calculate new parameters with accommodation RM#.-gW   
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness a#m T@l\  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 6&,9=(:J&R  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens =r^Pu|  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens \{ff7_mLo  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens vUB*Qm]Y\  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ,{BF`5bn|  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction bP7_QYQ6  
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    'Adjust parameters to account for accommodation 2E@g#:3  
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    '************************************************************************* +7j7zpw  
    'Aqueous thickness (Position of Lens) c? >;UzM  
    '************************************************************************* )No>Q :t  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ~2O1$ou  
    GetCustomElement eID, entity v[<;z(7Qk  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ef:YYt{|q  
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    ' Delete any shift(s) in z N9=?IFEe]  
    count = 0 4AYW'j C  
    While GetOperationCount(eID)>count ~Q+J1S]Fs  
        GetOperation eID, count, op `$ZBIe/u  
        If op.Type="ShiftZ" Then eV(   
            DeleteOperation eID,count vd0uI#g
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            count=count-1 5N$O  
        End If Z!I#Z2X  
        count=count+1 \{a 64  
    Wend d Z
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    'Set new shift in #* Iyvx  
    op.Type = "ShiftZ" }W nvz;]B  
    op.val1 = taq 8Wx7%@^O  
    op.parent = parID `bjPOA(g  
    AddOperation eID, op [wM]w  
    Print "Set aqueous humor thickness = " & taq-0.55 ;bkvdn}  
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    '************************************************************************* d1u6*&@lf  
    'Radius and conic constant of anterior lens =S|dzgS/  
    '************************************************************************* cR!Mn$m  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) |[MtUWEW  
    GetConic eID, entity, curv, conic {3K`yDF  
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    SetConic eID, entity, 1/Rant, CCant +H "j-:E@t  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant quiX"lV(  
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    '************************************************************************* ^) 5*?8#  
    'Radius and conic constant of posterior lens <MgC7S2I  
    '************************************************************************* )\QPUdOvx  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 7X/KQ97  
    GetConic eID, entity, curv, conic D9higsN  
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    SetConic eID, entity, 1/Rpost, CCpost aThvq%;  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost @K}Bll.E  
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    '************************************************************************* G(MLq"R6U  
    'Lens thickness (Position of posterior lens surface) !">EZX  
    '************************************************************************* W|V9:A  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) i`7:^v;  
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    ' Delete any z-shift(s) Lo5CVl
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    count = 0 lh*!f$2~  
    While GetOperationCount(eID)>count Sv[$.^mb  
        GetOperation eID, count, op ]TSzT"_r~~  
        If op.Type="ShiftZ" Then 'rSJ9Mw"x  
            DeleteOperation eID,count Fqg*H1I[  
            count=count-1 mLH,6rO9  
        End If G!g];7PG(  
        count=count+1 {i/7Nx
 
    Wend O*m9qF<  
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    'Set new z-shift .pPtBqp  
    op.Type = "ShiftZ" 7 MG<!U  
    op.val1 = tlens iB3C.wd-  
    op.parent = parID !X+}W[Ic^  
    AddOperation eID, op /H :Bu  
    Print "Set lens thickness = " & tlens /9SNXjfbt  
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    '************************************************************************* 5IFc"  
    'Lens index of refraction &f
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    '************************************************************************* osI0m7ws:  
    eID = FindMaterial( "Lens" ) X oh@(%  
    GetModelMaterial eID, mat ]vZ}4Xno  
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    mat.Nd = nlens {/K!cPp9  
    SetModelMaterial eID, mat SI:Iv:>  
    Print "Set lens index of refraction = " & nlens >o!5)\F  
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    '************************************************************************* =[IKwmCX  
    'Pupil diameter `{'h+v`  
    '************************************************************************* |#x]/AXa0/  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 9[Xe|5?c  
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    'Adjust pupil diameter (trimming volume inner hole) RgLkAHA  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Ct386j><  
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    ' Adjust pupil location to just in front of the lens XA
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    parID = FindFullName( "Geometry.Arizona Eye" ) (V#*}eGy  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) s Vg89I&  
    count = 0 9RJFj?^"
 
    While GetOperationCount(eID)>count ;  8u5  
        GetOperation eID, count, op mZ4I}_\,  
        If op.Type="ShiftZ" Then 48[b1#q]  
            DeleteOperation eID,count VpWpC&  
            count=count-1 2[5z6oG  
        End If xQ\S!py-  
        count=count+1 og8"#%  
    Wend [OQ+&\  
    op.Type = "ShiftZ" bC%}1wwh  
    op.val1 = taq-0.01 GE |P)VO  
    op.parent = parID 1eMaKT_=  
    AddOperation eID, op m
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    Print "Set pupil diameter = " & pupilDiam <(B: "wI  
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    'Update AZ Eye subassembly Description & 6~AY:0r  
    eID = FindFullName( "Geometry.Arizona Eye" ) 4zx_L8#Z  
    GetEntity eID, entity :1e'22[=.  
    entity.Description = "Accommodation = " & A & "D" 'kk B>g7B  
    SetEntity eID, entity l8By2{pN  
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    Update G?v]|wdI  
    Print "DONE!" 0
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End Sub T``~YoIdz  
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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： <PXnR\  
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Accommodation = 4 Diopters 3k5F$wf  
Pupil Diameter = 4 mm j8{,u6w)-  
Set aqueous humor thickness = 2.81 6D1tRo  
Set anterior lens radius = 10.4 and conic constant = -2.375869 Q)l~?Fx  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 d> L*2 g  
Set lens thickness = 3.927 2[yfo8H  
Set lens index of refraction = 1.42672 )}5f'TK  
Set pupil diameter = 4 <" F|K!Tz  
DONE! 5=9gH  
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