[分享]Arizona眼睛模型 [复制链接]

简介 f4mQDRlD  
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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。 cFV)zFu  
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模型 G`D~OI  
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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。 ;ndwVZ~,  
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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)hr  
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光源 r
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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。
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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。 [_X.Equ  
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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。 g[%iVZ  
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视网膜的散射 9aacW  
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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。 "J=A(w5   
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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。 e.n*IJ_fz  
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脚本 0kiV-yc   
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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： R)Y*<Na  
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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。 Y2oN.{IH  
余下的脚本计算与屈光度有关的所有参数。 |EpL~G
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分析 BIn7<.&  
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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。 #^zUaPV 7r  
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脚本代码 q)F@f /  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. [7+dZL[  
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Dim entity As T_ENTITY :L&d>Ii|'  
Dim op As T_OPERATION \*r]v;NcP  
Dim mat As T_MODELMATERIAL ?c0@A*:o  
Dim A As Double QP={b
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Dim pupilDiam As Double i4g99Kvl  
Dim eID As Long ,Srj38p  
Dim parID As Long t)n}S;iD  
Dim count As Integer 7zWr5U.  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Ed ,O>(  
Dim tlens As Double, nlens As Double rD*CLqK  
Dim curv As Double, conic As Double =e!o  
Dim ok As Long  dl;  
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Sub Main !Bqmw  
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    '用户输入对话框 <`Q*I Y  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 >6\rhx>  
        TextBox 220,21,40,21,.TextBox1 'default: 0 cfrvx^,2&  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 -A3>+G3[  
        OKButton 40,91,90,21 *0!IHr"fn  
        CancelButton 190,91,90,21 >}|Vmy[/  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 #>[5NQ;$'  
        TextBox 220,49,40,21,.TextBox2 'default: 4 #CcWsI>+w>  
    End Dialog W4V !7_  
    Dim dlg As UserDialog n+94./Mh  
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    ok = Dialog (dlg) ]$xN`O4W{  
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    If ok=0 Then    'cancel button was pressed (Tbw@BFk  
        Print "Execution cancelled." xJ[Xmre  
        End ztG!NZL  
    End If se,0Rvkt  
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    'Assign accommodation and pupil diameter & use defaults if field left empty *E1v  
    If dlg.TextBox1 = "" Then rZSX fgfr  
        A = 0           'Default accommodation ye^l~  
    Else mO~A}/je  
        A = CDbl(dlg.TextBox1) 25-5X3(>j=  
    End If LI/;`Y=  
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    If dlg.TextBox2 = "" Then dLnu\bSF  
        pupilDiam = 4   'Default pupil diameter 1}>uY  
    Else I6B4S"Q5<  
        pupilDiam = CDbl(dlg.TextBox2) " +n\0j;  
    End If !5escR!\D  
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    Print " " ;+W9EbY2  
    Print "Accommodation = " & A & " Diopters" @ApX43U(  
    Print "Pupil Diameter = " & pupilDiam & " mm" @b,&b6V  
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    ' Calculate new parameters with accommodation :!nBTw  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness KfkE'_F  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens X1GpLy)p  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens FY(C<fDRo{  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens BMlu>,  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Y#[>j4<T  
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    tlens = 3.767 + 0.04*A                  'Lens thickness klqN9d9k  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction z')zVoW,  
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    'Adjust parameters to account for accommodation v@KP~kp  
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    '************************************************************************* {6uhUb  
    'Aqueous thickness (Position of Lens) XnCrxj  
    '************************************************************************* :lGH31GG  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) #FL\9RXy  
    GetCustomElement eID, entity k=o>DaEh(  
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    parID = FindFullName( "Geometry.Arizona Eye" ) MaX:oG
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    ' Delete any shift(s) in z {#Vck\&  
    count = 0 o"5[~$O  
    While GetOperationCount(eID)>count Q[U_ 0O,A9  
        GetOperation eID, count, op ['l.]k-b}  
        If op.Type="ShiftZ" Then *[MK{m  
            DeleteOperation eID,count /Wqx@#  
            count=count-1 qp6*v&  
        End If Bt\z0*t=s  
        count=count+1 eJm7}\/6`  
    Wend X
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    'Set new shift in y_Tc$g~  
    op.Type = "ShiftZ" 7KzMa%=  
    op.val1 = taq \h&ui]V  
    op.parent = parID %j*i=  
    AddOperation eID, op ,*w  
    Print "Set aqueous humor thickness = " & taq-0.55 V&>\U?q:  
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    '************************************************************************* ZX Sl+k.  
    'Radius and conic constant of anterior lens #ErIot  
    '************************************************************************* OSsxO(;g  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) nfV32D|3  
    GetConic eID, entity, curv, conic d'yA"b]  

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    SetConic eID, entity, 1/Rant, CCant I )LO@  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ?(!<m'jEy  
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    '************************************************************************* H"g$qSx  
    'Radius and conic constant of posterior lens q:9#Vcw  
    '************************************************************************* clwJ+kku@  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) YsHZFF  
    GetConic eID, entity, curv, conic i(k]}Di:  
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    SetConic eID, entity, 1/Rpost, CCpost RRBok
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost vFL\O  
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    '************************************************************************* Po:)b  
    'Lens thickness (Position of posterior lens surface) # XD-a  
    '************************************************************************* bxS+ R\  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) /W6r{Et  
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    ' Delete any z-shift(s) u*<G20~A  
    count = 0 0H6^
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    While GetOperationCount(eID)>count ~ }<!ON;  
        GetOperation eID, count, op v.ftfL!  
        If op.Type="ShiftZ" Then +cw;a]o^>  
            DeleteOperation eID,count 4ZZ/R?AiK  
            count=count-1 g`skmHS89  
        End If zgdOugmmt_  
        count=count+1 :.+?v*%;n  
    Wend &$vW  
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    'Set new z-shift ~$zodrS9  
    op.Type = "ShiftZ" w;;.bz m  
    op.val1 = tlens t1)~J  
    op.parent = parID JERWz~n}  
    AddOperation eID, op :PrQ]ss@C5  
    Print "Set lens thickness = " & tlens J)w58/`?t  
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    '************************************************************************* 3KF[ v{  
    'Lens index of refraction f&\v+'[p  
    '************************************************************************* -n-rKN.T  
    eID = FindMaterial( "Lens" ) m,~ @1  
    GetModelMaterial eID, mat -'tgr6=|w"  
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    mat.Nd = nlens (]Z$mv!  
    SetModelMaterial eID, mat 0$n0fu  
    Print "Set lens index of refraction = " & nlens (L)tC*Qjc  
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    '************************************************************************* P|[i{h  
    'Pupil diameter ]Y3|*t(\  
    '************************************************************************* rsp?N{e  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 1,p[4k~Ww  
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    'Adjust pupil diameter (trimming volume inner hole) ;)^eDJ<  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 8q6b3q:c  
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    ' Adjust pupil location to just in front of the lens ys5b34JN  
    parID = FindFullName( "Geometry.Arizona Eye" ) K#=)]qIk  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) QOECpk-  
    count = 0 Tm8c:S^uq)  
    While GetOperationCount(eID)>count MS
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        GetOperation eID, count, op %5=XszS  
        If op.Type="ShiftZ" Then \(lt [=  
            DeleteOperation eID,count $lj1924?^  
            count=count-1 2EubMG  
        End If 4s<*rKm~  
        count=count+1 vG'JMzAm  
    Wend ndkV(#wQS  
    op.Type = "ShiftZ" t(4%l4i;X  
    op.val1 = taq-0.01 U!"+~d)  
    op.parent = parID 2WjQ-mM#  
    AddOperation eID, op N/A.1W  
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    Print "Set pupil diameter = " & pupilDiam -Bqn^ E  
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    'Update AZ Eye subassembly Description -f.<s!a  
    eID = FindFullName( "Geometry.Arizona Eye" ) U@<>2  
    GetEntity eID, entity  0u4:=Z}W  
    entity.Description = "Accommodation = " & A & "D" =kq!e  
    SetEntity eID, entity ':71;^zXf  
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    Update ;4E0%@R  
    Print "DONE!" w0x%7mg@  
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End Sub mbBd3y  
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如果屈光度是4，光瞳直径是4，则会输出如下数据：
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Accommodation = 4 Diopters .c'EXuI7),  
Pupil Diameter = 4 mm W@w#A]  
Set aqueous humor thickness = 2.81 +_gPZFpbx  
Set anterior lens radius = 10.4 and conic constant = -2.375869 J9^RP~>bs  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 b$P=rIB  
Set lens thickness = 3.927 )o'&f"/  
Set lens index of refraction = 1.42672 *yqEl O  
Set pupil diameter = 4 xp%,@]p  
DONE! r%hnl9
  
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