[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 [UquI "  
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。 FpE83}@".w  
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模型  M}}9  
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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。 epm  t  
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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. bvn?wK  
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光源 m^h"VH,   
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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。 B4R!V!Z*  
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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。 H|T:_*5  
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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。 oo3ZYA  
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视网膜的散射 {gl-tRC3  
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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。 RX>kOp29  
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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。 NaG1j+LN  
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脚本 wsP3hE' ]  
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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： k$}XZ,Q  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 Mc~(S$FU$  
余下的脚本计算与屈光度有关的所有参数。 +KD
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分析 FM0)/6I'x  
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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。 xv's52x  
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脚本代码 ;Y j_@=  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. g$?B!!qT  
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Dim entity As T_ENTITY Dq*>+1eW2  
Dim op As T_OPERATION +=|Q'V  
Dim mat As T_MODELMATERIAL /Y:_qsO1  
Dim A As Double sJ7r9O`x  
Dim pupilDiam As Double 9/{+,RpC  
Dim eID As Long er,R}v  
Dim parID As Long Sq UoXNw  
Dim count As Integer 4cr >sz  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double {]]nQ  
Dim tlens As Double, nlens As Double engql;  
Dim curv As Double, conic As Double z++*,2F  
Dim ok As Long %@G<B  
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Sub Main %xyt4}-)m  
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    '用户输入对话框 ToCB*GlL  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 st|$Fu  
        TextBox 220,21,40,21,.TextBox1 'default: 0 IJs*zzR  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 g/mVd;#o  
        OKButton 40,91,90,21 JQ%e'  
        CancelButton 190,91,90,21 W
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        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 7cr+a4T33  
        TextBox 220,49,40,21,.TextBox2 'default: 4 lK9us  
    End Dialog ]b.@i&M  
    Dim dlg As UserDialog gr4Hh/V
 
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    ok = Dialog (dlg) O=MO M  
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    If ok=0 Then    'cancel button was pressed )mB+#T<k-  
        Print "Execution cancelled." %TPnC'2  
        End |5Mhrb4.  
    End If %QVX1\>]  
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    'Assign accommodation and pupil diameter & use defaults if field left empty O!hg@[\B+  
    If dlg.TextBox1 = "" Then ?Re@`f+*  
        A = 0           'Default accommodation 1G=1FGvP  
    Else 
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        A = CDbl(dlg.TextBox1) Aw;~b&.U{_  
    End If  ;B^G<  
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    If dlg.TextBox2 = "" Then Jq l#z/z  
        pupilDiam = 4   'Default pupil diameter s59
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    Else 0J7[n*~  
        pupilDiam = CDbl(dlg.TextBox2) 1[[` ^v  
    End If !Jh-v  
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    Print " " DCPK1ql  
    Print "Accommodation = " & A & " Diopters" bguhx3s  
    Print "Pupil Diameter = " & pupilDiam & " mm" DFwkd/3"  
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    ' Calculate new parameters with accommodation ..Zuy|?w  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness \"V7O'S)&  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens mSY;hJi  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens w_ kHy_)  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens m_W\jz??k  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ]-bA{
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    tlens = 3.767 + 0.04*A                  'Lens thickness R^1sbmwk  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction zg.'  
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    'Adjust parameters to account for accommodation W% YJ.%I  
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    '************************************************************************* U8c0N<j  
    'Aqueous thickness (Position of Lens) 2Y(Phw2%  
    '************************************************************************* e=o<yf9>Q  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) MQ$[jOAqP  
    GetCustomElement eID, entity eZ[CqUJ&  
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    parID = FindFullName( "Geometry.Arizona Eye" ) g:dw%h  
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    ' Delete any shift(s) in z Pg{Dy>&2`I  
    count = 0 mEa\0oPGB  
    While GetOperationCount(eID)>count @g }r*U?  
        GetOperation eID, count, op YjdCCju  
        If op.Type="ShiftZ" Then fZ`b~ZBwIj  
            DeleteOperation eID,count <K=:_  
            count=count-1 ZK[4n5}  
        End If 'VS!<  
        count=count+1 -;a}'1HOE  
    Wend N$aLCX  
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    'Set new shift in .5p"o-:D  
    op.Type = "ShiftZ" W2O =dG`  
    op.val1 = taq ^o,P>u!9  
    op.parent = parID Y#{ L}  
    AddOperation eID, op 4'Z=T\:  
    Print "Set aqueous humor thickness = " & taq-0.55 "9!ln  
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    '************************************************************************* %`F6>J  
    'Radius and conic constant of anterior lens U; JZN  
    '************************************************************************* b/:9^&z  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) #~^#%G
 
    GetConic eID, entity, curv, conic VU J*\Sg  
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    SetConic eID, entity, 1/Rant, CCant SQDllG84E  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Jt\?
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    '************************************************************************* e%uPZ >'q  
    'Radius and conic constant of posterior lens |a%&7-;  
    '*************************************************************************
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;+'x_'a  
    GetConic eID, entity, curv, conic gtHWd;1&f  
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    SetConic eID, entity, 1/Rpost, CCpost OCnQSkj  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost kO{A]LnAH  
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    '************************************************************************* wb~#=6Y  
    'Lens thickness (Position of posterior lens surface) L9M0vkgri  
    '************************************************************************* yDg`9q.ckm  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) @;_xFL;{g  
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    ' Delete any z-shift(s) qPDe;$J)  
    count = 0 9_)*b  
    While GetOperationCount(eID)>count cK%Sty'8+  
        GetOperation eID, count, op b
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        If op.Type="ShiftZ" Then 87l(a,#J  
            DeleteOperation eID,count -f@~{rK.L  
            count=count-1 Jte:U*2  
        End If ZX[@P?A+-  
        count=count+1 `qn
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    Wend FBJw (.Jr  
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    'Set new z-shift o
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    op.Type = "ShiftZ" 141@$mMzE  
    op.val1 = tlens P&@ 2DI3m  
    op.parent = parID 1vk&;  
    AddOperation eID, op OPOL-2<wiy  
    Print "Set lens thickness = " & tlens MKzIY:ug  
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    '************************************************************************* m<qPj"g~L  
    'Lens index of refraction n`gW&5,,z  
    '************************************************************************* j;}!Yn  
    eID = FindMaterial( "Lens" ) 0aj4.H*%  
    GetModelMaterial eID, mat *;@V5[^3I?  
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    mat.Nd = nlens l&#&}3M  
    SetModelMaterial eID, mat HjCcfOej  
    Print "Set lens index of refraction = " & nlens #~QkS_  
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    '************************************************************************* ]yI~S(  
    'Pupil diameter M9so3L<N0  
    '************************************************************************* F7[ 55RcP  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 'b(V8x  
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    'Adjust pupil diameter (trimming volume inner hole) 1~rZka[s  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" -=5]B ;  
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    ' Adjust pupil location to just in front of the lens BN\Y N  
    parID = FindFullName( "Geometry.Arizona Eye" ) K@d,8[  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" )  {}x{OP  
    count = 0 (Klvctoy  
    While GetOperationCount(eID)>count d0ZbusHHb  
        GetOperation eID, count, op S 2vjjS  
        If op.Type="ShiftZ" Then bz$)@gLc  
            DeleteOperation eID,count Y6<"_  
            count=count-1 l@C3
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        End If G_OLUuK?C  
        count=count+1 vhsHyb  
    Wend !<'0 GOl  
    op.Type = "ShiftZ" !| ObNS  
    op.val1 = taq-0.01 -hv<8bC~4  
    op.parent = parID IbV 7}  
    AddOperation eID, op '1rHvz`B/"  
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    Print "Set pupil diameter = " & pupilDiam y?Vsp<  
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    'Update AZ Eye subassembly Description U42B(ow  
    eID = FindFullName( "Geometry.Arizona Eye" ) %#gHa  
    GetEntity eID, entity En&`m  
    entity.Description = "Accommodation = " & A & "D" \M(#FS  
    SetEntity eID, entity *Y"j 0Yob  
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    Update .MUoN
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    Print "DONE!" a[).'$S}'  
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End Sub -%I 0Q  
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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： #@qd.,]2  
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Accommodation = 4 Diopters *21foBfqh  
Pupil Diameter = 4 mm 0xZX%2E  
Set aqueous humor thickness = 2.81 22`N(_  
Set anterior lens radius = 10.4 and conic constant = -2.375869 &n 1 \^:  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 uIeD.I'@{5  
Set lens thickness = 3.927 L"Vi:zdp  
Set lens index of refraction = 1.42672 fwWE`BB  
Set pupil diameter = 4 iRwlK5(&  
DONE! 
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