[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 0?ZJJdI3  
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。 iy8UrgG;l  
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模型 w1aa5-aF  
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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。 \<~[uv'  
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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. 0,nDyTS^  
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光源 ,'F;s:WM,  
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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。 [X=-x=S,  
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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。 NZ'S~Lr  
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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。 :Cw|BX@??U  
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视网膜的散射 RT8xU;   
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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。 N|T%cdh:/  
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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。 m ,)4k&d  
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脚本 "Nn/vid;  
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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： &n6mXFF#>P  
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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。 Gb<)U[Hfd  
余下的脚本计算与屈光度有关的所有参数。 ,+KZn}>  
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分析 u}JL*}Q  
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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。 qXkc~{W_  
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脚本代码 pN&5vu30  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. A{Z=[]r1`E  
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Dim entity As T_ENTITY xpKD 'O=T  
Dim op As T_OPERATION KO<Yc`Fs  
Dim mat As T_MODELMATERIAL ddmTMfH  
Dim A As Double SgHLs
  
Dim pupilDiam As Double .%h.b6^  
Dim eID As Long 9;k_"@A6  
Dim parID As Long ny|ni\6  
Dim count As Integer } '.l'%  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double =4"D8UaHr  
Dim tlens As Double, nlens As Double @|6n.'f+  
Dim curv As Double, conic As Double 4iBp!k7  
Dim ok As Long G\?fWqx  
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Sub Main D:e9609  
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    '用户输入对话框 YBN@{P$  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 u{,e8. Z  
        TextBox 220,21,40,21,.TextBox1 'default: 0 0PI
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        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 EkgS*q_  
        OKButton 40,91,90,21 }xn\.M:ic  
        CancelButton 190,91,90,21 v9(->X'  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 'xm_oGWE  
        TextBox 220,49,40,21,.TextBox2 'default: 4 #Sr_PEo _  
    End Dialog z/)HJo2#  
    Dim dlg As UserDialog ]vMr@JM-G  
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    ok = Dialog (dlg) y~w2^VN=  
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    If ok=0 Then    'cancel button was pressed mVg-z~44T  
        Print "Execution cancelled." X#j-Ld{j  
        End rP>iPDf  
    End If n$g g$<  
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    'Assign accommodation and pupil diameter & use defaults if field left empty K4YpE}]u  
    If dlg.TextBox1 = "" Then 2--"@@  
        A = 0           'Default accommodation ya0L8`q  
    Else %|}obiV)  
        A = CDbl(dlg.TextBox1) ;t{Ew+s  
    End If ^6bU4bA  
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    If dlg.TextBox2 = "" Then @tWyc%t  
        pupilDiam = 4   'Default pupil diameter OW-[#r  
    Else X}Bo[YoY$  
        pupilDiam = CDbl(dlg.TextBox2) :3M2zV cf  
    End If <
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    Print " " {O9CYP:  
    Print "Accommodation = " & A & " Diopters" v*SSc5gFG  
    Print "Pupil Diameter = " & pupilDiam & " mm" ,4zwd@&O  
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    ' Calculate new parameters with accommodation zs<W>
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness %Sr/'7 K  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ;,![Lar5L  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens o?$kcI4  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens kRo dC(f @  
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    tlens = 3.767 + 0.04*A                  'Lens thickness &^3KF0\Q  

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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ! /;@kXN
 
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    'Adjust parameters to account for accommodation kwU~kcM  
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    '************************************************************************* _-eF &D  
    'Aqueous thickness (Position of Lens) 8d|omqe~P  
    '************************************************************************* wDswK "T  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) eL3HX _2(  
    GetCustomElement eID, entity -.-je"E  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 64;F g/t  
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    ' Delete any shift(s) in z ]#=43  
    count = 0 M>W-lp^3  
    While GetOperationCount(eID)>count >Y=HP&A<  
        GetOperation eID, count, op /HbxY  
        If op.Type="ShiftZ" Then ]L#6'|W  
            DeleteOperation eID,count c6FKpdn%  
            count=count-1 ~L$B]\/A5  
        End If ^j&'2n@9a  
        count=count+1 :9un6A9JS  
    Wend Rj 2N+59rg  
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    'Set new shift in 0vOt.LC/S  
    op.Type = "ShiftZ" B7r={P!0  
    op.val1 = taq r \+&{EEG  
    op.parent = parID eQ_dO]Q  
    AddOperation eID, op 8}9|hT;  
    Print "Set aqueous humor thickness = " & taq-0.55 q}gj.@Q"  
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    '************************************************************************* [5K&J-W  
    'Radius and conic constant of anterior lens !T;*F%G9  
    '************************************************************************* 4np,"^c  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) e+jp03m\W  
    GetConic eID, entity, curv, conic "Y0:Y?Vz"  
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    SetConic eID, entity, 1/Rant, CCant i(R&Q;{E^  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 9l).L L  
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    '************************************************************************* (qd$wv^h  
    'Radius and conic constant of posterior lens ?w'a^+H  
    '************************************************************************* tdZ,sHY6  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) \`?#V xz  
    GetConic eID, entity, curv, conic 8m,PsUp7  
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    SetConic eID, entity, 1/Rpost, CCpost N2:};a[ui5  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost fFP>$  
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    '************************************************************************* Sh'>
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    'Lens thickness (Position of posterior lens surface) Ei!t#'*D<  
    '************************************************************************* lrSdFJ%  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) `k y>M-  
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    ' Delete any z-shift(s) 3=o^Vv  
    count = 0 `H+~LVH  
    While GetOperationCount(eID)>count S~jl%]  
        GetOperation eID, count, op #hL<9j  
        If op.Type="ShiftZ" Then ,Q|[Yr  
            DeleteOperation eID,count KV1zx(WI  
            count=count-1 w?_y;&sbR  
        End If 1(!w xJ  
        count=count+1 +g36,!q  
    Wend 1Xy{&Ut\  
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    'Set new z-shift T&Dt;CSF  
    op.Type = "ShiftZ" Z}bUvr XP  
    op.val1 = tlens c\GJfsVk  
    op.parent = parID vd7%#sHH&  
    AddOperation eID, op (?MRbX]@  
    Print "Set lens thickness = " & tlens *&p`8:  
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    '************************************************************************* -$Bom  
    'Lens index of refraction d{_tOj$  
    '************************************************************************* nLK%5C  
    eID = FindMaterial( "Lens" ) 5G.A\`u%  
    GetModelMaterial eID, mat N<wy"N{iS  
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    mat.Nd = nlens fsc^8  
    SetModelMaterial eID, mat 0gY
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    Print "Set lens index of refraction = " & nlens n]&/?6}  
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    '************************************************************************* B ;Zsp  
    'Pupil diameter s_Y1rD*B  
    '************************************************************************* Xh==F:  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) fuJ6 fmT  
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    'Adjust pupil diameter (trimming volume inner hole) 0gNwC~IA8  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" |a@$K
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    ' Adjust pupil location to just in front of the lens gE8=#%1<  
    parID = FindFullName( "Geometry.Arizona Eye" ) :nki6Rkowt  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) $LUNA.  
    count = 0 $q#|B3N%  
    While GetOperationCount(eID)>count rg U$&O  
        GetOperation eID, count, op ?_9cFo59:  
        If op.Type="ShiftZ" Then 7aTo!T  
            DeleteOperation eID,count c_b^t09  
            count=count-1 G hH0-g{-  
        End If yO Cv-zm  
        count=count+1 CL/8p;
  
    Wend u?[P@_i<  
    op.Type = "ShiftZ" xQs2)  
    op.val1 = taq-0.01 .E:QZH'M  
    op.parent = parID v ?@Ys+V  
    AddOperation eID, op ^T\JFzV  
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    Print "Set pupil diameter = " & pupilDiam )W9$_<Z  
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    'Update AZ Eye subassembly Description ~ar8e  
    eID = FindFullName( "Geometry.Arizona Eye" ) "El$Sat`  
    GetEntity eID, entity <~# ZtD$G  
    entity.Description = "Accommodation = " & A & "D" #p~tkQ:'1  
    SetEntity eID, entity W&`_cGoP  
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    Update q[]EVs0$ew  
    Print "DONE!" d|Wpub  
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End Sub #tG/{R  
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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： -[OGZP`8  
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Accommodation = 4 Diopters "PGEiLY  
Pupil Diameter = 4 mm %Bg} a  
Set aqueous humor thickness = 2.81 Bt|S!tEy  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ry}CND(nB  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 !pl<  
Set lens thickness = 3.927 B]]_rl,  
Set lens index of refraction = 1.42672 5o\yhYS:  
Set pupil diameter = 4 ~]?Q'ER  
DONE! ^.j
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