[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 H8V@KB  
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。 89P'WFOFK  
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模型 J0FJ@@  
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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。 ZmAo9>'Kg  
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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. tvcM< e20  
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光源 l#&\,T  
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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。 UId?a}J  
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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。 'Esz#@R  
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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。 "{x+ \Z\  
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视网膜的散射 <lP5}F87  
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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。 hVW1l&s  
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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。 6+/BYN!&4  
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脚本 AZva  
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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： =8AL>:_  
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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。 z6Zd/mt~x  
余下的脚本计算与屈光度有关的所有参数。 =\gK<Xh  
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分析 Q|7;Zsd:  
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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。 ntn ~=oL  
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脚本代码 Rts.jm>[  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. ggUw4w/e  
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Dim entity As T_ENTITY P.3kcZ   
Dim op As T_OPERATION , RU   
Dim mat As T_MODELMATERIAL *~^M_wej  
Dim A As Double S7B?[SPrN[  
Dim pupilDiam As Double ?'U@oz8 B  
Dim eID As Long \Wb3JQ)  
Dim parID As Long * & : J  
Dim count As Integer },,K6*P  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double n!L}4Nmp  
Dim tlens As Double, nlens As Double oiItQ4{<  
Dim curv As Double, conic As Double UQq Qim  
Dim ok As Long e/zz.cd){  
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Sub Main %Vhj<
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    '用户输入对话框 &X)^G#  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 &Y-jK<  
        TextBox 220,21,40,21,.TextBox1 'default: 0 7upN:7D-  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 aPHNX)  
        OKButton 40,91,90,21 =z#j9'n$@  
        CancelButton 190,91,90,21 ;M5]XCPk  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 "(yw(/  
        TextBox 220,49,40,21,.TextBox2 'default: 4 A[H"(E#k  
    End Dialog \iAs  
    Dim dlg As UserDialog s}?QA cC  
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    ok = Dialog (dlg) ms#|Yl1/|  
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    If ok=0 Then    'cancel button was pressed gt!tDu  
        Print "Execution cancelled." EO"G(v  
        End ( c +M"s  
    End If m5lTf
 
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    'Assign accommodation and pupil diameter & use defaults if field left empty FLQ>,=O  
    If dlg.TextBox1 = "" Then qTV.DCP  
        A = 0           'Default accommodation )odz/\9n3c  
    Else gCaxZ~o  
        A = CDbl(dlg.TextBox1) aA-
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    End If R!2E`^{Wl  
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    If dlg.TextBox2 = "" Then <,Fj}T-  
        pupilDiam = 4   'Default pupil diameter dyt.(2  
    Else Q6d>tqWhq  
        pupilDiam = CDbl(dlg.TextBox2) B+[L/C}=;  
    End If P.kf|,8L  
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    Print " " =/bC0bb{i  
    Print "Accommodation = " & A & " Diopters" $;j{?dvm.  
    Print "Pupil Diameter = " & pupilDiam & " mm" }M &hcw<  
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    ' Calculate new parameters with accommodation |qtZb}"|  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 2 P9{?Y  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 2 5Ia  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens >(a[b@[K  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens gk4DoOj#P  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens |?ma?  
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    tlens = 3.767 + 0.04*A                  'Lens thickness kV$VKag*A  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction *[tLwl.  
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    'Adjust parameters to account for accommodation 1_z~<d @?;  
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    '************************************************************************* jiP^Hz"e  
    'Aqueous thickness (Position of Lens) Hf9F:yH  
    '************************************************************************* z}2  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 9Nu:{_Yo
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    GetCustomElement eID, entity
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    parID = FindFullName( "Geometry.Arizona Eye" ) j_}f6d/h  
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    ' Delete any shift(s) in z 3'[ g2JR  
    count = 0 g>-u9%aa  
    While GetOperationCount(eID)>count R^Y_i  
        GetOperation eID, count, op [+b&)jN*2  
        If op.Type="ShiftZ" Then Sxcp [g;  
            DeleteOperation eID,count k9iB-=X?4s  
            count=count-1 t8t+wi!  
        End If ^Dys#
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        count=count+1 7z3YzQ=Kg  
    Wend Ui}%T]  
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    'Set new shift in -{eI6#z|\A  
    op.Type = "ShiftZ" _+. )8   
    op.val1 = taq %SwhNn  
    op.parent = parID `yrJ}f  
    AddOperation eID, op \(ju0qFqH  
    Print "Set aqueous humor thickness = " & taq-0.55 n4/Jx*  
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    '************************************************************************* ^q/_D%]C  
    'Radius and conic constant of anterior lens A(wuRXnVWK  
    '************************************************************************* W.TdhJW9  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" )  +D|E8sz8  
    GetConic eID, entity, curv, conic w~WW2w  
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    SetConic eID, entity, 1/Rant, CCant "ac$S9@~  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant YFs!,fw'  
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    '************************************************************************* '))=y@M  
    'Radius and conic constant of posterior lens C7_#D O6"  
    '************************************************************************* w>6cc#>q  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;g_<i_*x#  
    GetConic eID, entity, curv, conic *hkNJ  
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    SetConic eID, entity, 1/Rpost, CCpost <CGJ:% AY  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 6|]e}I@<2  
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    '************************************************************************* \mDBOC0eK  
    'Lens thickness (Position of posterior lens surface) G*rlU  
    '************************************************************************* 4i(?5p>f  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) n{xL1A=9  
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    ' Delete any z-shift(s) *[b2
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    count = 0 |M(0CYO  
    While GetOperationCount(eID)>count 3V@!}@y,F6  
        GetOperation eID, count, op x^/453Lk  
        If op.Type="ShiftZ" Then aX|LEZ;D>  
            DeleteOperation eID,count fb
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            count=count-1 )jed@?  
        End If z-
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        count=count+1 Ys@G0}\3G  
    Wend x4;ndck%U  
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    'Set new z-shift &E`=pe/e  
    op.Type = "ShiftZ" D:Fi/JY~  
    op.val1 = tlens )UAkg  
    op.parent = parID nsyeid*  
    AddOperation eID, op S~Yu;  
    Print "Set lens thickness = " & tlens 6G]hsgro  
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    '************************************************************************* C}(9SASs%  
    'Lens index of refraction g\=e86  
    '************************************************************************* QLOcgU^  
    eID = FindMaterial( "Lens" ) jt6,id)&  
    GetModelMaterial eID, mat pEX|zee  
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    mat.Nd = nlens ::8c pUc`f  
    SetModelMaterial eID, mat \wxLt}T-Q  
    Print "Set lens index of refraction = " & nlens l$3YJ.n|s~  
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    '************************************************************************* b]@@
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    'Pupil diameter f%Vdao[  
    '************************************************************************* Vl%jpjqP  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 8 ;o*c6+  
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    'Adjust pupil diameter (trimming volume inner hole) `rZS\A  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" G~KYFNHr  
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    ' Adjust pupil location to just in front of the lens l|5;&(Y+s  
    parID = FindFullName( "Geometry.Arizona Eye" ) Rg~F[j$N  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) )_\q)t"=  
    count = 0 FFpG>+*3  
    While GetOperationCount(eID)>count j=n<s</V  
        GetOperation eID, count, op |7%#
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        If op.Type="ShiftZ" Then !7jVKI80  
            DeleteOperation eID,count ,'>O#kD  
            count=count-1 J~k'b2(p3  
        End If [WW ~SOJe  
        count=count+1 U['|t<^uf  
    Wend fe!{vrS  
    op.Type = "ShiftZ" )T!3du:M  
    op.val1 = taq-0.01 D);w)`  
    op.parent = parID m+9~f_}  
    AddOperation eID, op C7xmk;c w  
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    Print "Set pupil diameter = " & pupilDiam G'f
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    'Update AZ Eye subassembly Description D%!GY1wdn  
    eID = FindFullName( "Geometry.Arizona Eye" ) ^Rc*X'Iz(!  
    GetEntity eID, entity 'rDai[  
    entity.Description = "Accommodation = " & A & "D" <zt12
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    SetEntity eID, entity EiCEB;*z|d  
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    Update ']DUCu  
    Print "DONE!" i16kPU  
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End Sub OS sYmF  
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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： !?5YXI,  
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Accommodation = 4 Diopters =gQ^,x0R9  
Pupil Diameter = 4 mm ,f^ICM  
Set aqueous humor thickness = 2.81 #VynADPs`o  
Set anterior lens radius = 10.4 and conic constant = -2.375869 5dkXDta[G  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 f_'8l2jK1i  
Set lens thickness = 3.927 e]-%P(}Z  
Set lens index of refraction = 1.42672 |VQmB/a  
Set pupil diameter = 4 g[$4a4X  
DONE! W$Sc@!M3{  
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