[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 ]5$eAYq  
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。 0Emr<n  
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模型 )Ib<F7v  

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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。 Z]j*9#G1s  
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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. u*tN)f3  
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光源 ' )?
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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。 _;~,Cgfi  
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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。 -sjd&)~S[  
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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。 -xDGH  
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视网膜的散射 x7<\]94  
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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。 OV%Q3$15  

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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。 bV8!"{  
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脚本 l
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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： W0k0$\i
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 DWID$w  
余下的脚本计算与屈光度有关的所有参数。 OnF3lCmu  
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分析 v|Yh w  
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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。 a_ `[Lj  
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脚本代码 59%tXiO  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. {2+L@  
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Dim entity As T_ENTITY +\|Iu;w  
Dim op As T_OPERATION 2A\,-*pc  
Dim mat As T_MODELMATERIAL QR Ei7@t  
Dim A As Double qOUqs'7/]  
Dim pupilDiam As Double -,+q#F  
Dim eID As Long
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Dim parID As Long :^fcC[$K  
Dim count As Integer raCi 8  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double UY<e&Npo  
Dim tlens As Double, nlens As Double C%U`"-%n@7  
Dim curv As Double, conic As Double %^8^yZz  
Dim ok As Long jWY$5Vq<H  
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Sub Main dpFVN[\oK  
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    '用户输入对话框 i-'9AYyw  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 #~=
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        TextBox 220,21,40,21,.TextBox1 'default: 0 DZv=\<$,LF  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 #fL8
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        OKButton 40,91,90,21 4mHvgnT!WA  
        CancelButton 190,91,90,21 .p=sBLp8  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 E-{^E.w1  
        TextBox 220,49,40,21,.TextBox2 'default: 4 -CR?<A4mud  
    End Dialog 8?i7U<CB  
    Dim dlg As UserDialog b L]erYm  
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    ok = Dialog (dlg) PmR~c,  
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    If ok=0 Then    'cancel button was pressed T`9u!#mT=  
        Print "Execution cancelled." z)xSN;x  
        End ? BE6  
    End If 2PeR   
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    'Assign accommodation and pupil diameter & use defaults if field left empty A)
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    If dlg.TextBox1 = "" Then PI~1GyJr@;  
        A = 0           'Default accommodation Qq@G\eRo  
    Else d~?X/sJ t  
        A = CDbl(dlg.TextBox1) Pf$pt  
    End If W?We6.%  
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    If dlg.TextBox2 = "" Then Kv rX{F=  
        pupilDiam = 4   'Default pupil diameter 3 AHY|  
    Else PT^c^{V  
        pupilDiam = CDbl(dlg.TextBox2) 8srBHslI  
    End If Khe!g1=&X  
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    Print " " /c$\X<b);  
    Print "Accommodation = " & A & " Diopters" $Y9jrR'w  
    Print "Pupil Diameter = " & pupilDiam & " mm" v @O&t4  
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    ' Calculate new parameters with accommodation xESjM1A)  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness O0:)X)b  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 7nVRn9Hn  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 37q@rDm2  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens K9kUS  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens W>=o*{(YO  
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    tlens = 3.767 + 0.04*A                  'Lens thickness jV/CQM5a+  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction bC^(U`y32  
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    'Adjust parameters to account for accommodation kwud?2E  
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    '************************************************************************* $x#FgD(iI  
    'Aqueous thickness (Position of Lens) m$LVCB  
    '************************************************************************* -L3|&O_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) XG@`ZJhU6  
    GetCustomElement eID, entity Nk;iiz+_p  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ;+I/I9~  
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    ' Delete any shift(s) in z @[6,6:h|  
    count = 0 cDrebU  
    While GetOperationCount(eID)>count \@~UDP]7  
        GetOperation eID, count, op kL90&nP  
        If op.Type="ShiftZ" Then /:\3 \{?0m  
            DeleteOperation eID,count M|[ZpM+  
            count=count-1 =1oNZKBP  
        End If Pz_NDI  
        count=count+1 QR> Y%4 ;h  
    Wend W0zbxJKjd  
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    'Set new shift in d"U(`E=H9  
    op.Type = "ShiftZ" MDRe(rF=  
    op.val1 = taq  UkfB^hA  
    op.parent = parID _0pO8o-x  
    AddOperation eID, op k]rLjcB  
    Print "Set aqueous humor thickness = " & taq-0.55 .A1\J@b  
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    '************************************************************************* nW+YOX|+  
    'Radius and conic constant of anterior lens XjE>k!=I  
    '************************************************************************* #*c F8NV-  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Y& ] 8 {  
    GetConic eID, entity, curv, conic Q0{z).&\(e  
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    SetConic eID, entity, 1/Rant, CCant =/+#PVO  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ~"!a9GZ  
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    '************************************************************************* Ze!92g  
    'Radius and conic constant of posterior lens 8@M'[jT  
    '************************************************************************* m=b~i^@  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) C2<CWPn<  
    GetConic eID, entity, curv, conic @("}]/O V:  
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    SetConic eID, entity, 1/Rpost, CCpost )~rB}>^Z  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost `BnP[jF  
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    '************************************************************************* y1BgK>R  
    'Lens thickness (Position of posterior lens surface) 2D([Z-<i  
    '************************************************************************* DI&MC9j(   
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) c[0oh.  
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    ' Delete any z-shift(s) ); 6,H.v  
    count = 0 _1jw=5^P\i  
    While GetOperationCount(eID)>count 1]\TI7/n  
        GetOperation eID, count, op =V|Nn0E  
        If op.Type="ShiftZ" Then EX?h0Uy  
            DeleteOperation eID,count 5@XV6  
            count=count-1 *(*+`qZL{(  
        End If -{9Gagy2&  
        count=count+1 2[dIOb4b  
    Wend aQcN&UA@  
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    'Set new z-shift yty`2$O  
    op.Type = "ShiftZ" agaq`^[(P  
    op.val1 = tlens el'j
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    op.parent = parID Lm.`+W5  
    AddOperation eID, op 74zSP/G
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    Print "Set lens thickness = " & tlens B#tdLv"I  
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    '************************************************************************* BDpF}  
    'Lens index of refraction Z~3u:[x";  
    '************************************************************************* IMad$AKc  
    eID = FindMaterial( "Lens" ) ygvzdYd  
    GetModelMaterial eID, mat p,n\__  
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    mat.Nd = nlens _@E "7<\  
    SetModelMaterial eID, mat `)[dVfxA  
    Print "Set lens index of refraction = " & nlens 7Qh_8
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    '************************************************************************* 8Inx/>eOI  
    'Pupil diameter 3cu9[~K  
    '************************************************************************* )!C7bTv 4  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) g2'x#%ET  
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    'Adjust pupil diameter (trimming volume inner hole) !"! ii$@  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" } gkP  
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    ' Adjust pupil location to just in front of the lens S\|^ULrH  
    parID = FindFullName( "Geometry.Arizona Eye" ) +t>XxYScx  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 0VIZ=-e  
    count = 0 79z)C35~  
    While GetOperationCount(eID)>count +Pw,Nl\KD  
        GetOperation eID, count, op &r:m&?!|VQ  
        If op.Type="ShiftZ" Then k ]bPI$  
            DeleteOperation eID,count _>v0R'  
            count=count-1 $WNG07]tU  
        End If 2 `5=0E1k  
        count=count+1 1#D<ZN  
    Wend B+Q+0tw*i  
    op.Type = "ShiftZ" NQ!<f\m4n  
    op.val1 = taq-0.01 C*O ,rm}  
    op.parent = parID Y*\6o7  
    AddOperation eID, op 6To:T[ z#  
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    Print "Set pupil diameter = " & pupilDiam ! IgoL&=  
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    'Update AZ Eye subassembly Description i>"dBJh]b  
    eID = FindFullName( "Geometry.Arizona Eye" ) .\)k+ R  
    GetEntity eID, entity !2tw,QM
  
    entity.Description = "Accommodation = " & A & "D" 3`rIV*&_{  
    SetEntity eID, entity HZuiVW8  
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    Update !u%9;>T7  
    Print "DONE!" bqjr0A7{  
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End Sub Wo2v5-  
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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： b=_{/F*b?  
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Accommodation = 4 Diopters 'g]=.K+@}  
Pupil Diameter = 4 mm #Jv43
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Set aqueous humor thickness = 2.81 Q!x`M4   
Set anterior lens radius = 10.4 and conic constant = -2.375869 @%H8"A  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 JE9>8+  
Set lens thickness = 3.927 QxA0I+i  
Set lens index of refraction = 1.42672 '&)D>@g  
Set pupil diameter = 4 = uk`pj  
DONE! !Z-9tYO  
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