[分享]Arizona眼睛模型 [复制链接]

简介 ?k`UQi]Q  
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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。 9CG&MvF c  
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模型 #$X _,+<HZ  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 S-5O$EnD  
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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. XM f>B|
  
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光源 ,n{R,]y\  
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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。 jP#I](\eG  
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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。 f cnv[B..{  
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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。 O1
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视网膜的散射 3S .2  
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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。 Lb#PiTJI  
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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。 (ys<{Y-;  
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脚本 N6Dv1_c,  
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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： &Qe2 }e$  

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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。 EMPujik-  
余下的脚本计算与屈光度有关的所有参数。 dVMLn4[,MA  
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分析 P{HR='2  
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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。 <qVOd.9c  
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脚本代码 >,.\`.0  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. IOa@dUh7a,  
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Dim entity As T_ENTITY 'Z|Czd8E  
Dim op As T_OPERATION V/xjI<,  
Dim mat As T_MODELMATERIAL _q4Yq'dI  
Dim A As Double 8@ S@^C*F  
Dim pupilDiam As Double /8 yv8  
Dim eID As Long ZFtJoGaR  
Dim parID As Long '!`| H 3  
Dim count As Integer 7X8*7'.2  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Q9c*I,Oj  
Dim tlens As Double, nlens As Double _88X-~.  
Dim curv As Double, conic As Double ]
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Dim ok As Long  c& $[a%s  
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Sub Main ltyhYPS  
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    '用户输入对话框 `4e| I.`^r  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Rp!"c  
        TextBox 220,21,40,21,.TextBox1 'default: 0 4&%E?_M  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ~i.rk#{?D  
        OKButton 40,91,90,21 ,4k3C#!.i  
        CancelButton 190,91,90,21 <nK@+4EH"o  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 !^EA}N.u  
        TextBox 220,49,40,21,.TextBox2 'default: 4 $ nMx#~>a  
    End Dialog 11Uu5e!.  
    Dim dlg As UserDialog B 74  
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    ok = Dialog (dlg) Q[FDk63;w  
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    If ok=0 Then    'cancel button was pressed &XW~l>!+  
        Print "Execution cancelled." }rnu:7  
        End iVo-z#  
    End If nm)/BK  
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    'Assign accommodation and pupil diameter & use defaults if field left empty
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    If dlg.TextBox1 = "" Then ;&!QN#_  
        A = 0           'Default accommodation e(FT4KD~  
    Else UR(i_T&w  
        A = CDbl(dlg.TextBox1) :2+z_+k}<  
    End If p<&>1}j=  
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    If dlg.TextBox2 = "" Then 4hYK$!"r
 
        pupilDiam = 4   'Default pupil diameter 7jr+jNsowj  
    Else EztuVe  
        pupilDiam = CDbl(dlg.TextBox2) BqpJvRJd  
    End If +U>Y.YP  
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    Print " " We*uZ?+  
    Print "Accommodation = " & A & " Diopters" lv~ga2>z  
    Print "Pupil Diameter = " & pupilDiam & " mm" 3lKs>HE0  
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    ' Calculate new parameters with accommodation `=Rxnl,<U  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness I,"q:QS+  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens I]42R;Sc  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ^W`RBrJay  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens yr*~?\  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens W"\+jHF"  
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    tlens = 3.767 + 0.04*A                  'Lens thickness |QQ(1#d  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction R%\<al$O  
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    'Adjust parameters to account for accommodation gc b8eB,  
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    '************************************************************************* Hq&MePl[  
    'Aqueous thickness (Position of Lens) 9|NF)~Q}'  
    '************************************************************************* ')iyD5/4  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) %|ioNXMu  
    GetCustomElement eID, entity MlLM $Y-@  
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    parID = FindFullName( "Geometry.Arizona Eye" ) =B`=f,,#3  
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    ' Delete any shift(s) in z M5xMTP-  
    count = 0 i?V:+0#q\]  
    While GetOperationCount(eID)>count  B`vC>  
        GetOperation eID, count, op 9`CJhu  
        If op.Type="ShiftZ" Then 1_8@yO  
            DeleteOperation eID,count WDr=+=Zj  
            count=count-1 "|N0oEG&  
        End If M+)ENve  
        count=count+1 w}M)]kY  
    Wend mi@uX@
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    'Set new shift in WopA7J,  
    op.Type = "ShiftZ" 
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    op.val1 = taq 8M]QDgd.  
    op.parent = parID !,sQB_09C  
    AddOperation eID, op @Y ?p-&  
    Print "Set aqueous humor thickness = " & taq-0.55 qZlL6  
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    '************************************************************************* DD6K[\  
    'Radius and conic constant of anterior lens /N")uuv  
    '************************************************************************* \_)mWK,h  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) @lqI,Ce5  
    GetConic eID, entity, curv, conic H1 i+j;RN  
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    SetConic eID, entity, 1/Rant, CCant *8/
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    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Y$fF"pG?  
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    '************************************************************************* ^a|  
    'Radius and conic constant of posterior lens "b"|ay  
    '************************************************************************* L9l]0C37e  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) }_Y\6fcd  
    GetConic eID, entity, curv, conic Z5*O\kJv  
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    SetConic eID, entity, 1/Rpost, CCpost eMP0BS"  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost YdYaLTz  
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    '*************************************************************************
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    'Lens thickness (Position of posterior lens surface) xo(>nFjo  
    '************************************************************************* X1Kze  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) )X6I#q8  
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    ' Delete any z-shift(s) }To-c'  
    count = 0 !OOOc  
    While GetOperationCount(eID)>count K~qKr<)  
        GetOperation eID, count, op `R-VJR 2"  
        If op.Type="ShiftZ" Then JaN53,&<  
            DeleteOperation eID,count ?zYR;r2'b)  
            count=count-1 &hWYw+yH\  
        End If wFJ*2W:  
        count=count+1 Gd|j
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    Wend C`aUitL}  
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    'Set new z-shift kvt^s0T8Q  
    op.Type = "ShiftZ" vtq47i  
    op.val1 = tlens Mu_'C$zA  
    op.parent = parID 1Nz#,IdQ  
    AddOperation eID, op kP&Ekjt@  
    Print "Set lens thickness = " & tlens G%%5lw!y'  
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    '************************************************************************* zbDK$g6  
    'Lens index of refraction 4@@gC&:Y  
    '************************************************************************* (V`ddP-  
    eID = FindMaterial( "Lens" ) OuB[[L  
    GetModelMaterial eID, mat raZ0B,;eFu  
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    mat.Nd = nlens djDE0-QxcR  
    SetModelMaterial eID, mat ,(kaC.Em  
    Print "Set lens index of refraction = " & nlens %:Zp7O2UB'  
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    '************************************************************************* D ~NWP%H  
    'Pupil diameter fBPJ8VY  
    '************************************************************************* VS+5{w:t  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) M:%L
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    'Adjust pupil diameter (trimming volume inner hole) (y2P."  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" (=tu
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    ' Adjust pupil location to just in front of the lens 6/|"y  
    parID = FindFullName( "Geometry.Arizona Eye" ) B(pHo&ox  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) K$-|7tJon  
    count = 0 .X6V>e)(3  
    While GetOperationCount(eID)>count XK
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        GetOperation eID, count, op
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        If op.Type="ShiftZ" Then P}D5 j  
            DeleteOperation eID,count ^NO;A=9b[  
            count=count-1 :LD+B1$y  
        End If P~@I`r567  
        count=count+1 9<*<-x{A17  
    Wend 4$4n9`odE  
    op.Type = "ShiftZ" Q0TKM>  
    op.val1 = taq-0.01 62>/0_m5  
    op.parent = parID L%f$ &  
    AddOperation eID, op \3cg\Q+~  
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    Print "Set pupil diameter = " & pupilDiam +fq;o8q  
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    'Update AZ Eye subassembly Description s;:quM  
    eID = FindFullName( "Geometry.Arizona Eye" ) 6X$iTJ[\x  
    GetEntity eID, entity x_x|D|@wM  
    entity.Description = "Accommodation = " & A & "D" &3Mps[u:h  
    SetEntity eID, entity Mm#=d?YUHJ  
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    Update _P{v=`]Eu  
    Print "DONE!" |r53>,oR<:  
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End Sub b'4r5@GO  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： ^Kh>La:>O  
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Accommodation = 4 Diopters  SwmX_F#_  
Pupil Diameter = 4 mm aB4L$M8x  
Set aqueous humor thickness = 2.81 Py#iC#g~  
Set anterior lens radius = 10.4 and conic constant = -2.375869 < nyk:
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Set posterior lens radius = -4.424557 and conic constant = -3.081019 (OHd}YQ  
Set lens thickness = 3.927 g?!;04  
Set lens index of refraction = 1.42672 JT 5+d ,  
Set pupil diameter = 4 8R.`*  
DONE! 0mR  
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