[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 fHFE){  
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。 WsB?C&>x  
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模型 1qA;/-Zr<o  

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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。 })%{AfDRF  
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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. z{QqY.Gu{G  
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光源 59u}W 0  
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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。 $&c*'3  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 ?r4>"[  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 !N^@4*  
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视网膜的散射 #'`{Qv0,  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 d'> x(Yi  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 UiNP3T
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脚本 (9)Q ' 'S  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： 3so%gvY.'  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 1Y,Z %d  
余下的脚本计算与屈光度有关的所有参数。 ,esmV-  
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分析 XWw804ir  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。  \=o-  
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脚本代码 %iB,IEw  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. l,).p  
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Dim entity As T_ENTITY !R$`+wZ62  
Dim op As T_OPERATION F0# 'WfM#  
Dim mat As T_MODELMATERIAL \2z>?i)  
Dim A As Double Bw.i}3UT6  
Dim pupilDiam As Double p ll)Y  
Dim eID As Long Qb%J8juRf  
Dim parID As Long ,x
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Dim count As Integer a'T;x`b8U,  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 4M T 7`sr  
Dim tlens As Double, nlens As Double i#O SC5ZI  
Dim curv As Double, conic As Double 7 8,n%=nG  
Dim ok As Long gG
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Sub Main y7<|_:00  
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    '用户输入对话框 MK*r+xfSae  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 (k P9hcV  
        TextBox 220,21,40,21,.TextBox1 'default: 0 {`_i`  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 p<%d2@lp  
        OKButton 40,91,90,21 a9Vi];  
        CancelButton 190,91,90,21 \<K5ZIWV  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 I+(nu47ZT  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ^rz_f{c]-  
    End Dialog N>E_%]Ch  
    Dim dlg As UserDialog gDzK{6Z}  
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    ok = Dialog (dlg) {{1G`;|v9  
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    If ok=0 Then    'cancel button was pressed x~sBzTa  
        Print "Execution cancelled." E`J@hl$N  
        End C,zohlpC  
    End If ]###w;  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ig"L\ C"
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    If dlg.TextBox1 = "" Then DfB7*+x{  
        A = 0           'Default accommodation 
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    Else T4F/w|Q  
        A = CDbl(dlg.TextBox1) {)Xy%QV  
    End If r|Z{-*`  
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    If dlg.TextBox2 = "" Then a.Vuu)+Quw  
        pupilDiam = 4   'Default pupil diameter !~Z"9(v'C  
    Else ,z6~?6m  
        pupilDiam = CDbl(dlg.TextBox2) 0"#HJA44  
    End If 0{mex4  
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    Print " " ! P4*+')M  
    Print "Accommodation = " & A & " Diopters" !m$jk2<  
    Print "Pupil Diameter = " & pupilDiam & " mm" 8k79&|  
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    ' Calculate new parameters with accommodation fy$1YI>!Q  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness n@w%Z
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 2SLU:=<3  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens X?Au/  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 9u:Q
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens >3bCTE  
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    tlens = 3.767 + 0.04*A                  'Lens thickness %)n=x ne  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 4P0}+  
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    'Adjust parameters to account for accommodation 2pAW9R#UV-  
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    '************************************************************************* n`KY9[0U=  
    'Aqueous thickness (Position of Lens) KlqY@Xt  
    '************************************************************************* OJxl<Q=z  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 9FX-1,Jx  
    GetCustomElement eID, entity <vP=zk  
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    parID = FindFullName( "Geometry.Arizona Eye" ) KmF]\:sMD  
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    ' Delete any shift(s) in z oU/5 a>9~  
    count = 0 nP$9CA  
    While GetOperationCount(eID)>count ;Qq\DFe.w  
        GetOperation eID, count, op y)*RV;^  
        If op.Type="ShiftZ" Then <uJ@:oWG7  
            DeleteOperation eID,count ctUp=po  
            count=count-1 Y$zSQ_k;U  
        End If pXUS
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        count=count+1 A=4OWV?  
    Wend 5X+A"X ;C  
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    'Set new shift in He)%S]RLk  
    op.Type = "ShiftZ" a9G8q>h]O  
    op.val1 = taq UI#h&j5pW  
    op.parent = parID `2snz1>!j  
    AddOperation eID, op {8aTV}Ha2  
    Print "Set aqueous humor thickness = " & taq-0.55 ;);kEq/=P  
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    '************************************************************************* M`>E|"<  
    'Radius and conic constant of anterior lens % `3jL7|  
    '************************************************************************* "]dI1 g_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 26nx`w?j(  
    GetConic eID, entity, curv, conic $^P0F9~0  
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    SetConic eID, entity, 1/Rant, CCant O84i;S+-p  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant xA
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    '************************************************************************* v1[29t<I!  
    'Radius and conic constant of posterior lens ys~x$  
    '************************************************************************* Dj+f
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) %LV9=!w  
    GetConic eID, entity, curv, conic ?EL zj  
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    SetConic eID, entity, 1/Rpost, CCpost ;fJ.8C  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost (?c-iKGc  
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    '************************************************************************* @VBcJ{e,  
    'Lens thickness (Position of posterior lens surface) Zh,71Umz  
    '************************************************************************* P%6~&woF  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) TO_e^A#  
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    ' Delete any z-shift(s) q@&6#B  
    count = 0 H.c7Nle  
    While GetOperationCount(eID)>count g*Ph
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        GetOperation eID, count, op SIllU  
        If op.Type="ShiftZ" Then Th%zn2R B  
            DeleteOperation eID,count Kgv T"s.  
            count=count-1 <[v[ci  
        End If AdmC&!nH  
        count=count+1 -12U4h<e  
    Wend j [a(#V{  
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    'Set new z-shift ;*N5Y}?j'  
    op.Type = "ShiftZ" :A
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    op.val1 = tlens @,}UWU  
    op.parent = parID #ABCDi={zA  
    AddOperation eID, op lk!@?  
    Print "Set lens thickness = " & tlens .6> w'F{>  
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    '************************************************************************* FlQGgVN  
    'Lens index of refraction B1gR5p0  
    '************************************************************************* 43w}qY1  
    eID = FindMaterial( "Lens" ) *R"/|Ka  
    GetModelMaterial eID, mat 9$Y=orpWxr  
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    mat.Nd = nlens CAlCDfKW}  
    SetModelMaterial eID, mat UBs4K*h|  
    Print "Set lens index of refraction = " & nlens $:6!H:ty  
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    '************************************************************************* =%7-ZH9  
    'Pupil diameter H+#FSdy#  
    '************************************************************************* $j~RWfw-  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) $xqa{L%B  
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    'Adjust pupil diameter (trimming volume inner hole) z{543~Og59  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" zqku e%^?-  
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    ' Adjust pupil location to just in front of the lens vI?, 47Hj+  
    parID = FindFullName( "Geometry.Arizona Eye" ) 0_/[k*Re  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) >~f]_puT  
    count = 0 3%6?g*  
    While GetOperationCount(eID)>count "tZe>>I  
        GetOperation eID, count, op :3PH8TL  
        If op.Type="ShiftZ" Then y7{?Ip4[  
            DeleteOperation eID,count 0J|3kY-n>  
            count=count-1 :m;p:l|W  
        End If _aphkeqd  
        count=count+1 ~Ei<Z`3}7"  
    Wend 5G#n"}T  
    op.Type = "ShiftZ" T|$H#n}  
    op.val1 = taq-0.01 =M1I>  
    op.parent = parID #Z#-Ht  
    AddOperation eID, op #mT"gs  
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    Print "Set pupil diameter = " & pupilDiam V#HuIgf-  
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    'Update AZ Eye subassembly Description U:`Kss`  
    eID = FindFullName( "Geometry.Arizona Eye" ) ~u{uZ(~
  
    GetEntity eID, entity OI*H,Z"  
    entity.Description = "Accommodation = " & A & "D" t
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    SetEntity eID, entity 3$tdwe$S  
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    Update W^Yxny  
    Print "DONE!" O1lNAcpeM  
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End Sub I]575\bA  
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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： !if   
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Accommodation = 4 Diopters oDR%\VY6T  
Pupil Diameter = 4 mm W!X@  
Set aqueous humor thickness = 2.81 x:;kSh  
Set anterior lens radius = 10.4 and conic constant = -2.375869 8}[).d160  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 XSDpRo  
Set lens thickness = 3.927 }EPY^VIw  
Set lens index of refraction = 1.42672 0@(&eH=  
Set pupil diameter = 4 |>Vb9:q9Po  
DONE! $`c:&  
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