[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 v{Cts3?Br  
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。 
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模型 "pq#A*  
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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。 ty]JUvR@  
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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. N#{d_v^H?d  
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光源 b Jt397  
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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。 \7Hzj0hSi  
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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。 =O~1L m;  
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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。 .>>@q!!s!  
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视网膜的散射 `+$'bNPn&  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 zsA6(?)u  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 W>eJGZ<  
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脚本 BZEY^G  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： aWek<Y~+  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 /Ik_U?$*  
余下的脚本计算与屈光度有关的所有参数。 XyJ*>;q  
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分析 aKS 2p3   
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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。 dgpo4'c
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脚本代码 :k8>)x] )  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. `48jL3|  
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Dim entity As T_ENTITY @i&LKr8  
Dim op As T_OPERATION {%. _cR2  
Dim mat As T_MODELMATERIAL KL#F5\ E  
Dim A As Double aUSxy8%  
Dim pupilDiam As Double @gENv~m<OI  
Dim eID As Long X}p#9^%N  
Dim parID As Long Xhtc0\0"(  
Dim count As Integer {"!V&}
 
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ~1wAk0G`n  
Dim tlens As Double, nlens As Double ,0NVb7F;k  
Dim curv As Double, conic As Double 2H;&E1:  
Dim ok As Long dsX{5  
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Sub Main r4dG83qg  
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    '用户输入对话框 *XS@Ku   
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 -(~Tu>KaH  
        TextBox 220,21,40,21,.TextBox1 'default: 0 x,IU]YW@  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 QZef=  
        OKButton 40,91,90,21 X'.}#R1  
        CancelButton 190,91,90,21 pez*kU+9  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 l"RX`N@In  
        TextBox 220,49,40,21,.TextBox2 'default: 4 rJ
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    End Dialog yw"FI!M  
    Dim dlg As UserDialog YNc%[S[u^1  
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    ok = Dialog (dlg) _X;^'mqf~  
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    If ok=0 Then    'cancel button was pressed 3!Zd]1$  
        Print "Execution cancelled." *ntq;]  
        End 1c~c_Cc4  
    End If cf1Ve\(YGI  
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    'Assign accommodation and pupil diameter & use defaults if field left empty yk!,{Q?<$  
    If dlg.TextBox1 = "" Then OJ8W'"`L&  
        A = 0           'Default accommodation <%hSBDG!x  
    Else f<9H#S:  
        A = CDbl(dlg.TextBox1) Y oNg
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    End If GBu&2}  
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    If dlg.TextBox2 = "" Then wfM$JYfI  
        pupilDiam = 4   'Default pupil diameter ~/Aw[>_;  
    Else pA='(G  
        pupilDiam = CDbl(dlg.TextBox2) [%YA42_`LD  
    End If :N\*;>  
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    Print " " 8HX(1nNj}  
    Print "Accommodation = " & A & " Diopters" 3m#v|52oj  
    Print "Pupil Diameter = " & pupilDiam & " mm" Xw`vf7z*  
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    ' Calculate new parameters with accommodation ]p(+m_F  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness D#x D-c  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens *6e`km  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens oaHg6
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ~IZ'zuc  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Me yQ`%  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Zq2dCp%  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction g)!B};AA  
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    'Adjust parameters to account for accommodation Q7&Yy25   
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    '************************************************************************* Xlw&hKS  
    'Aqueous thickness (Position of Lens) WfBA5  
    '************************************************************************* ul/=1]1?  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) djS?$WBpU  
    GetCustomElement eID, entity :HYqm*v;W  
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    parID = FindFullName( "Geometry.Arizona Eye" ) Gbwcb
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    ' Delete any shift(s) in z %O%+TR7Z  
    count = 0 YM 0f_G=
 
    While GetOperationCount(eID)>count I$\dT1m$  
        GetOperation eID, count, op m8rKH\FD}  
        If op.Type="ShiftZ" Then D5\$xdlJy  
            DeleteOperation eID,count ]NNLr;p  
            count=count-1 mwZesSxB_  
        End If <wFR%Y/j  
        count=count+1 ^ox^gw)  
    Wend Pqo_+fL+  
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    'Set new shift in /[VafR!  
    op.Type = "ShiftZ" ?xGxr|+a  
    op.val1 = taq w8wF;:>  
    op.parent = parID ~&
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    AddOperation eID, op J<p<5):R;  
    Print "Set aqueous humor thickness = " & taq-0.55 }el.qZ  
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    '************************************************************************* p \; * :  
    'Radius and conic constant of anterior lens @4B+<,i   
    '************************************************************************* s!~M,zsQN  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) {lT9gJ+  
    GetConic eID, entity, curv, conic >>rW-&  
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    SetConic eID, entity, 1/Rant, CCant qo}-m7  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ?O8NyCeb7  
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    '************************************************************************* i@6MO'y  
    'Radius and conic constant of posterior lens gAhCNOp  
    '************************************************************************* lJ3/^Htn  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) &9$0v"`H  
    GetConic eID, entity, curv, conic LZMdW #,[  
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    SetConic eID, entity, 1/Rpost, CCpost Vl{CD>$,  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost <GF)5QB  
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    '*************************************************************************
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    'Lens thickness (Position of posterior lens surface) 5~<>h~yJ  
    '************************************************************************* -OB72!sKU  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) >-r\]/^  
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    ' Delete any z-shift(s) Fm3-Sn|Po  
    count = 0 nSz Fs(]f  
    While GetOperationCount(eID)>count tv+q~TFB=Z  
        GetOperation eID, count, op V`TXn[7  
        If op.Type="ShiftZ" Then X"(!\{ySI;  
            DeleteOperation eID,count ?;0=>3p*0
 
            count=count-1 4\pi<#X  
        End If ;Z-Cn.  
        count=count+1 ;*:d)'A  
    Wend I}puN!  
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    'Set new z-shift I.fV_ H^  
    op.Type = "ShiftZ" n4 KiC!*i0  
    op.val1 = tlens Bg-C:Ok2'  
    op.parent = parID -DlKFN  
    AddOperation eID, op Z_iu^Q  
    Print "Set lens thickness = " & tlens
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    '************************************************************************* yrdJX  
    'Lens index of refraction D2[wv+#)  
    '************************************************************************* H:`W\CP7_  
    eID = FindMaterial( "Lens" ) HyiuU`  
    GetModelMaterial eID, mat Xf:CGR8_  
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    mat.Nd = nlens T73oW/.0X?  
    SetModelMaterial eID, mat C0jmjZ%w@  
    Print "Set lens index of refraction = " & nlens jm =E_86_  
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    '************************************************************************* uw LT$  
    'Pupil diameter .hg<\-:_  
    '************************************************************************* 4adCMfP7.  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) m1gJ"k6 `j  
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    'Adjust pupil diameter (trimming volume inner hole) -vGyEd7  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" doFp53NhV  
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    ' Adjust pupil location to just in front of the lens }Tu_?b`RUm  
    parID = FindFullName( "Geometry.Arizona Eye" ) rzDqfecOmW  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) en=Z[ZIPO  
    count = 0 vROl}s;  
    While GetOperationCount(eID)>count kNI m90,g  
        GetOperation eID, count, op *<x]gV  
        If op.Type="ShiftZ" Then 7WiVor$g-  
            DeleteOperation eID,count  c?}C{  
            count=count-1 >RHK6c  
        End If 3SpDV'}  
        count=count+1 9u1_L`+b  
    Wend |^S[Gr w  
    op.Type = "ShiftZ" Q~,E K  
    op.val1 = taq-0.01 6O"Vy  
    op.parent = parID 3HO4h\mp  
    AddOperation eID, op Y">Q16(  
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    Print "Set pupil diameter = " & pupilDiam j*I0]!-  
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    'Update AZ Eye subassembly Description MQQiQ 2  
    eID = FindFullName( "Geometry.Arizona Eye" ) YM 7P!8Gc  
    GetEntity eID, entity {Xwin$C  
    entity.Description = "Accommodation = " & A & "D" <z#r3J  
    SetEntity eID, entity dDi 1{s  
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    Update B6 x5E  
    Print "DONE!" Fy`VQ\%7t  
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End Sub ^M,t`r{  
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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： 5`^"<wNI  
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Accommodation = 4 Diopters oMLpl3pl  
Pupil Diameter = 4 mm &'WgBjP  
Set aqueous humor thickness = 2.81 n-Dr/c4  
Set anterior lens radius = 10.4 and conic constant = -2.375869 WN>.+qM~8  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 O_-.@uo./(  
Set lens thickness = 3.927 QDBptI:  
Set lens index of refraction = 1.42672 5iG|C ~  
Set pupil diameter = 4 T>g1! -^  
DONE! OMJr.u  
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