[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 ESASsRzk  
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。 |#2
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模型 bt&vik _  
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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。 sq)Nn&5A  
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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. 6y5arP*6e  
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光源 -GKelz?h>  
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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。 WD?V1:>+  
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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。 _mkI;<d]$T  
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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。 xZhD6'Zzz  
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视网膜的散射 \qTn"1bQ  
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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。 [a |fm*B!  
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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。 bA^a@ lv a  
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脚本 =}"hC`3e  
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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： RYhdf  
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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。 ^#Y6 E  
余下的脚本计算与屈光度有关的所有参数。 jh?7+(Cw  
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分析 P3 Evv]sB@  
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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。 h9-Ky@X`  
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脚本代码 dB,#`tc=,  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. Uy1xNb/d  
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Dim entity As T_ENTITY $^XPk#$m  
Dim op As T_OPERATION D7(t6C=FP  
Dim mat As T_MODELMATERIAL mT>p
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Dim A As Double y,>m#6hx#  
Dim pupilDiam As Double 2&d&$Jg  
Dim eID As Long c\'pA^m6  
Dim parID As Long &zd7t6  
Dim count As Integer BT1'@qF  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ? 7EVmF  
Dim tlens As Double, nlens As Double ;E"mB4/)  
Dim curv As Double, conic As Double iHn]yv3 #  
Dim ok As Long T> 'Vaxo  
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Sub Main -Mv
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    '用户输入对话框 y~=hM   
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 . R}y"O\  
        TextBox 220,21,40,21,.TextBox1 'default: 0 %Tb|Yfyr C  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 'nS3o.}  
        OKButton 40,91,90,21 Rqz
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        CancelButton 190,91,90,21 FlG^'UD  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 I}v#r8'!  
        TextBox 220,49,40,21,.TextBox2 'default: 4 !dH&IEP~  
    End Dialog gWo~o]f  
    Dim dlg As UserDialog <^_?hN8.  
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    ok = Dialog (dlg) j*`!o/=LI  
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    If ok=0 Then    'cancel button was pressed j1C.#-P[  
        Print "Execution cancelled." 9tEKA|8  
        End kAliCD)  
    End If &FVlTo1  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 4Z<l>!  
    If dlg.TextBox1 = "" Then @<=#i  
        A = 0           'Default accommodation aF
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    Else BZc-  
        A = CDbl(dlg.TextBox1) ejY5n2V#=  
    End If RT"2Us]*  
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    If dlg.TextBox2 = "" Then P$>kBW53  
        pupilDiam = 4   'Default pupil diameter h}>/Z3*  
    Else PEt8,,x<"  
        pupilDiam = CDbl(dlg.TextBox2) 7 aD&\?  
    End If X/Rx]}[   
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    Print " " l_-n&(N2<[  
    Print "Accommodation = " & A & " Diopters" cEjdImAzU  
    Print "Pupil Diameter = " & pupilDiam & " mm" n{r#K_  
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    ' Calculate new parameters with accommodation xBfe8lor  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness >m1V9A  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens aZ>\*1
 
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens dd7nO :]  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens u=}bq{  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens &E riskI  
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    tlens = 3.767 + 0.04*A                  'Lens thickness s [F' h-y  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction X7d.Ie  
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    'Adjust parameters to account for accommodation -yQ\3wli`  
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    '************************************************************************* NVqC|uEAF  
    'Aqueous thickness (Position of Lens) kok^4VV  
    '************************************************************************* Qr%Jm{_o  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) u\6]^T6  
    GetCustomElement eID, entity '(X[ w=WXy  
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    parID = FindFullName( "Geometry.Arizona Eye" ) q[OTaSQ~u^  
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    ' Delete any shift(s) in z L##8+OJ.L  
    count = 0 X/8iJ-KB  
    While GetOperationCount(eID)>count SKpPR;=q|:  
        GetOperation eID, count, op }`N2ZxC0AQ  
        If op.Type="ShiftZ" Then 6_5d  
            DeleteOperation eID,count H'GYJ ?U"  
            count=count-1 }j(2Dl  
        End If :sVHY2x  
        count=count+1 `$sY^EX  
    Wend 7Jx-W|  
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    'Set new shift in {ogZT7w}  
    op.Type = "ShiftZ" }t51U0b%  
    op.val1 = taq AMD?LjY~  
    op.parent = parID gGX0+L@E  
    AddOperation eID, op ? TT8|Os  
    Print "Set aqueous humor thickness = " & taq-0.55 N.{jM[\F  
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    '************************************************************************* yLz,V}  
    'Radius and conic constant of anterior lens K>cz63}S  
    '************************************************************************* x:?a;muf  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) #xP!!.DF(  
    GetConic eID, entity, curv, conic MFH"$t+  
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    SetConic eID, entity, 1/Rant, CCant q|u8CX  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant TwuX-b  
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    '************************************************************************* GX@W"y  
    'Radius and conic constant of posterior lens Y <Znv%M  
    '************************************************************************* crNjI`%tw  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) R@<_Hb;Aeb  
    GetConic eID, entity, curv, conic =`1m-   
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    SetConic eID, entity, 1/Rpost, CCpost 7/|F9fF@M  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost E./__Mz@  
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    '************************************************************************* "@{4.v^}!  
    'Lens thickness (Position of posterior lens surface) NYjS  
    '************************************************************************* nQ642i%RQ  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) W ~Jzqp9g  
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    ' Delete any z-shift(s) EDHg'q  
    count = 0 `.>k)=F&  
    While GetOperationCount(eID)>count ~#x:z^U  
        GetOperation eID, count, op }
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        If op.Type="ShiftZ" Then $,KP]~?  
            DeleteOperation eID,count SH vaV[C  
            count=count-1 om}/f`  
        End If 7?MB8tJ5r4  
        count=count+1 `c'  
    Wend %GX uuE}mX  
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    'Set new z-shift DikdC5>O>m  
    op.Type = "ShiftZ" `V&1]C8x  
    op.val1 = tlens CZyz;Jtk  
    op.parent = parID ^Ti_<<X  
    AddOperation eID, op P{S\pWZkk  
    Print "Set lens thickness = " & tlens _~;&)cn,0  
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    '************************************************************************* SE^j=1  
    'Lens index of refraction zLsb`)!  
    '************************************************************************* x6^l6N  
    eID = FindMaterial( "Lens" ) ^sifEgG*d  
    GetModelMaterial eID, mat =`Po<7D  
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    mat.Nd = nlens 6Wpxp\  
    SetModelMaterial eID, mat iuC7Y|  
    Print "Set lens index of refraction = " & nlens |(V?,^b^ro  
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    '************************************************************************* D<U 9m3  
    'Pupil diameter D XV@DQ  
    '************************************************************************* :zdEq")v  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 5@`F.F
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    'Adjust pupil diameter (trimming volume inner hole) wG1y,u'  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" O' +"d%2'  
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    ' Adjust pupil location to just in front of the lens E6Q]A~  
    parID = FindFullName( "Geometry.Arizona Eye" ) /!GKh5|  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" )
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    count = 0 l{Jt sI  
    While GetOperationCount(eID)>count ]~-*hOcQ4  
        GetOperation eID, count, op
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        If op.Type="ShiftZ" Then 5@P%iBA4(3  
            DeleteOperation eID,count kE/`n],1U  
            count=count-1 Y1{B c<tC  
        End If ^GMJ~
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        count=count+1 |3}5:k  
    Wend <B6[i*&  
    op.Type = "ShiftZ" 01udlW.  
    op.val1 = taq-0.01 "8N"Udu  
    op.parent = parID ]3*P:$Rq  
    AddOperation eID, op iF!mV5#  
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    Print "Set pupil diameter = " & pupilDiam } h[>U  
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    'Update AZ Eye subassembly Description y 'OlQ2U  
    eID = FindFullName( "Geometry.Arizona Eye" ) o+nG3kRD  
    GetEntity eID, entity c=6ahX}d  
    entity.Description = "Accommodation = " & A & "D" ,c>N}*6h=W  
    SetEntity eID, entity 4j>fI)FUW  
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    Update 0rD#s{?  
    Print "DONE!" XCDSmZ  
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End Sub JqEW=5  
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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： ;7Y[c}V1^  
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Accommodation = 4 Diopters @mf({Q>  
Pupil Diameter = 4 mm 17}$=#SX  
Set aqueous humor thickness = 2.81 Jf7frzw  
Set anterior lens radius = 10.4 and conic constant = -2.375869 $;2)s}ci  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 !@G)$g=<  
Set lens thickness = 3.927 ZK6Hvc0  
Set lens index of refraction = 1.42672 J$Fnm\  
Set pupil diameter = 4 kbxg_UI;  
DONE! L=O lyHO  
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