[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 ({m["d  
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。 W$EX6jTGI  
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模型 (8GJLs 8  
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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。 w6Dysg:  
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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. c[sC 2  
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光源 n j; KnZ  
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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。 ,G"?fQ7zR  
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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。 
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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。 'V4.umj1~  
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视网膜的散射 $ n  n4  
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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。 EQ?4?  
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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。 S]<G|mn,  
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脚本 *fSa8CV  
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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： m"86O:S#d  
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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。 (C6Y*Zm\  
余下的脚本计算与屈光度有关的所有参数。 u>k;PUH4  
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分析 dH?pQ 
 
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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。 qpp:h_E  
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脚本代码 pNVao{::5  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. p&vQ*}  
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Dim entity As T_ENTITY =xG9a_^v  
Dim op As T_OPERATION `+"QhQ4w  
Dim mat As T_MODELMATERIAL @3VL _g:  
Dim A As Double w\$b(HC  
Dim pupilDiam As Double ip1jY!   
Dim eID As Long (O?z6g  
Dim parID As Long U> q&+:+  
Dim count As Integer 3vrQY9H>  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double pKr3(5~  
Dim tlens As Double, nlens As Double P-+^YN,  
Dim curv As Double, conic As Double qn+mlduU  
Dim ok As Long 61jDI^:  

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Sub Main m#8}!u&  
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    '用户输入对话框 =1\'xz}p?  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 !Y\hF|[z  
        TextBox 220,21,40,21,.TextBox1 'default: 0 r>z8DX@  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Ty@&s58a  
        OKButton 40,91,90,21 ef!I |.FW  
        CancelButton 190,91,90,21 0n(Q@O  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 T}u'  
        TextBox 220,49,40,21,.TextBox2 'default: 4 >"`:w  
    End Dialog foL`{fA  
    Dim dlg As UserDialog 9^c_^-8n<}  
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    ok = Dialog (dlg) WZFV8'  
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    If ok=0 Then    'cancel button was pressed 4~o\Os+8  
        Print "Execution cancelled." Gi{1u}-0  
        End yM\1n  
    End If L`Qiu@  
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    'Assign accommodation and pupil diameter & use defaults if field left empty xmVK{Q YT$  
    If dlg.TextBox1 = "" Then fF *a/\h %  
        A = 0           'Default accommodation f(##P|3>R  
    Else \!w7N :m  
        A = CDbl(dlg.TextBox1) :;7qup  
    End If r*tGT_/6  
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    If dlg.TextBox2 = "" Then [2&Fnmjk}X  
        pupilDiam = 4   'Default pupil diameter .6/[X`*  
    Else pl7!O9bo  
        pupilDiam = CDbl(dlg.TextBox2) 7L]fCw p[  
    End If <Ft.{aNq$c  
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    Print " " -MOf[f^  
    Print "Accommodation = " & A & " Diopters" aEL6-['(  
    Print "Pupil Diameter = " & pupilDiam & " mm" ueqR@i  
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    ' Calculate new parameters with accommodation VBd.5YW  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness  ;xry  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ,:;_j<g
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    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens gbSZ- ej  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens HPt"  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens /5wvXk|@  
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    tlens = 3.767 + 0.04*A                  'Lens thickness { >4exyu6  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction -bE{yT)7  
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    'Adjust parameters to account for accommodation ) tsaDG-E  
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    '************************************************************************* vB#3jI  
    'Aqueous thickness (Position of Lens) K_}vmB\2l  
    '************************************************************************* rZzto;NDS  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) rb,&i1  
    GetCustomElement eID, entity .Mm8\].  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 0iHK1Pt}  
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    ' Delete any shift(s) in z r$0"Y-a  
    count = 0 >Y[{m $-  
    While GetOperationCount(eID)>count p-zLi!  
        GetOperation eID, count, op
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        If op.Type="ShiftZ" Then [kn`~
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            DeleteOperation eID,count C96|T>bk  
            count=count-1
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        End If Z*kg= hs^  
        count=count+1 w3B*%x)  
    Wend %>pglI  
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    'Set new shift in dGHRHXi  
    op.Type = "ShiftZ" S .1~#  
    op.val1 = taq 44b'40  
    op.parent = parID T!J\Dm-  
    AddOperation eID, op jaNkWTm:  
    Print "Set aqueous humor thickness = " & taq-0.55 LN_6>u  
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    '************************************************************************* GyT{p#l  
    'Radius and conic constant of anterior lens P 7gS M  
    '************************************************************************* R$cg\DD  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) $s?q>Z)  
    GetConic eID, entity, curv, conic +#n[55d  
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    SetConic eID, entity, 1/Rant, CCant 8thG-  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant $ V}s3  
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    '************************************************************************* R]L7?=  
    'Radius and conic constant of posterior lens @hg1&pfxZ<  
    '************************************************************************* '{Iv?gh"  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 1p`XK";g  
    GetConic eID, entity, curv, conic +D$\^ <#  
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    SetConic eID, entity, 1/Rpost, CCpost $yhQ)@#1
 
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost a i}8+L8-  
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    '************************************************************************* OTalR;:]r  
    'Lens thickness (Position of posterior lens surface) iB[%5i-  
    '************************************************************************* Wh 8fC(BE  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) `O0v2?/f0  
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    ' Delete any z-shift(s) kG\+f>XQ  
    count = 0 O@?? NF6G  
    While GetOperationCount(eID)>count IO|">a6  
        GetOperation eID, count, op QH#|R92:  
        If op.Type="ShiftZ" Then Hz*!c#  
            DeleteOperation eID,count ~@TNVkw  
            count=count-1 rzEE|  
        End If Mg-Kh}U  
        count=count+1 i]xyD'0  
    Wend k`kmmb>  
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    'Set new z-shift /]iv9e{uh(  
    op.Type = "ShiftZ" [%z~0\lu8  
    op.val1 = tlens `<C)oF\~f  
    op.parent = parID >8oRO  
    AddOperation eID, op 9LzQp`In  
    Print "Set lens thickness = " & tlens Hi<{c  
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    '************************************************************************* ysDfp'
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    'Lens index of refraction
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    '************************************************************************* -=O9D-x=  
    eID = FindMaterial( "Lens" ) _T8#36iR  
    GetModelMaterial eID, mat ;lnh;0B  
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    mat.Nd = nlens V5%B,.d:  
    SetModelMaterial eID, mat 3[aCy4O  
    Print "Set lens index of refraction = " & nlens q"`1cFD  
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    '************************************************************************* fqFE GyeNr  
    'Pupil diameter 4LJUO5(y@  
    '************************************************************************* q-X)tH_+w@  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) lLyMm8E%pZ  
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    'Adjust pupil diameter (trimming volume inner hole) ZGe+w](  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" uZ\ >  
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    ' Adjust pupil location to just in front of the lens ??ah  
    parID = FindFullName( "Geometry.Arizona Eye" ) (X QgOR#  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) xSug-  
    count = 0 !+=jD3HTJ  
    While GetOperationCount(eID)>count P ;PS+S9  
        GetOperation eID, count, op n3jA[p:  
        If op.Type="ShiftZ" Then VQ{}S $jQ  
            DeleteOperation eID,count fA2H8"r  
            count=count-1 P%g[!9 '  
        End If (,[m}Qb?!  
        count=count+1 ^SVdaQ{7  
    Wend WDWb7  
    op.Type = "ShiftZ" OjJKloy'  
    op.val1 = taq-0.01 k2_ "  
    op.parent = parID Vq -!1.v3  
    AddOperation eID, op p4bQCI  
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    Print "Set pupil diameter = " & pupilDiam a>(LFpVk}  
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    'Update AZ Eye subassembly Description mc~d4<$`!  
    eID = FindFullName( "Geometry.Arizona Eye" ) g\OPidY  
    GetEntity eID, entity ?SkYFa`u*  
    entity.Description = "Accommodation = " & A & "D" )g(2xUk-y  
    SetEntity eID, entity JyvXNV,  
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    Update c<r`E  
    Print "DONE!" aM,>LKNbQ  
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End Sub #3f\,4K5  
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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： dNB56E)5`J  
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Accommodation = 4 Diopters xbxU`2/  
Pupil Diameter = 4 mm ?tQUZO  
Set aqueous humor thickness = 2.81 TGY^,H>J  
Set anterior lens radius = 10.4 and conic constant = -2.375869 e(@YBQ/Z  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 8Tyf#`'I  
Set lens thickness = 3.927 @=E@ *@g  
Set lens index of refraction = 1.42672 s,\!@[N  
Set pupil diameter = 4 dUk^DI,:l  
DONE! &|LZ%W0Fb  
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