[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 "+`u ]  
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。 _akjgwu  
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模型 &w`Ho)P  
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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。 7B5b +  
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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. CK|AXz+EN  
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光源 #)48dW!n  
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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。 +R;LHRS%  
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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。 -k2|`t _  
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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。 (n2_HePE  
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视网膜的散射 7PUy`H,&  
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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。 I0x;rP  
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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。 >zw@!1{1  
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脚本 eAjR(\f>  
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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： -'WR9M?fq  
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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。 YD9vWk\/  
余下的脚本计算与屈光度有关的所有参数。 [0kZyjCq@  
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分析 x{So  
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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。 K$:btWSm  
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脚本代码 IkA~+6UY  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. K9VP@[zbJ  
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Dim entity As T_ENTITY 83#<Yxk~  
Dim op As T_OPERATION 86?~N  
Dim mat As T_MODELMATERIAL k{lXK\zN  
Dim A As Double g_>E5z.  
Dim pupilDiam As Double )?l7I*  
Dim eID As Long |\| v%`r2  
Dim parID As Long Y<N#{)Q  
Dim count As Integer zJUT<%[U  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double a?Y>hvI  
Dim tlens As Double, nlens As Double gOE?  
Dim curv As Double, conic As Double
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Dim ok As Long ~%
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Sub Main P+_1*lOG  
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    '用户输入对话框 XMxm2-%olP  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 T0b/txS  
        TextBox 220,21,40,21,.TextBox1 'default: 0 P9S)7&+DL  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 GlJOb|WOX  
        OKButton 40,91,90,21 Su +<mW  
        CancelButton 190,91,90,21 5UK}AkEe&x  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 2'Kh>c2  
        TextBox 220,49,40,21,.TextBox2 'default: 4 x1Gc|K/-  
    End Dialog @q@I(%_`  
    Dim dlg As UserDialog KMl3`+i  
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    ok = Dialog (dlg) "dYT>w  
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    If ok=0 Then    'cancel button was pressed  N PqO b  
        Print "Execution cancelled." >*+n`"6  
        End c0X1})q$  
    End If Zba<|C  
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    'Assign accommodation and pupil diameter & use defaults if field left empty rCA0c8  
    If dlg.TextBox1 = "" Then zpNt[F?~1  
        A = 0           'Default accommodation 5;XU6Rz!  
    Else c7tO'`q$e  
        A = CDbl(dlg.TextBox1) GFnwj<V+{  
    End If 5~#oQ&  
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    If dlg.TextBox2 = "" Then *rV{(%\m  
        pupilDiam = 4   'Default pupil diameter D&],.N  
    Else !SLfAFcS  
        pupilDiam = CDbl(dlg.TextBox2) cb. -AlqQ  
    End If =4!m]*y  
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    Print " " sYk#XNH  
    Print "Accommodation = " & A & " Diopters" e%9zY{ABR%  
    Print "Pupil Diameter = " & pupilDiam & " mm" /7.//klN  
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    ' Calculate new parameters with accommodation aHitPPlq  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness nVP|
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens .i#'IS0c  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens UZ:z|a3  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens <Y;w I#C  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens &v:[+zw  
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    tlens = 3.767 + 0.04*A                  'Lens thickness WK{F  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 6"r _Y7%  
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    'Adjust parameters to account for accommodation g<8Oezi 65  
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    '************************************************************************* PT4iy<  
    'Aqueous thickness (Position of Lens) G) 37?A)  
    '************************************************************************* <J}JYT  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) l
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    GetCustomElement eID, entity Z:,`hW*A6  
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    parID = FindFullName( "Geometry.Arizona Eye" ) [BEQ ~A_I  
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    ' Delete any shift(s) in z S.U#lAn(  
    count = 0 x-q_sZ^8  
    While GetOperationCount(eID)>count og4mLoLA  
        GetOperation eID, count, op fzN?X=  
        If op.Type="ShiftZ" Then !bn=b>+  
            DeleteOperation eID,count sP>-k7K
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            count=count-1 <(45(6fQ  
        End If +z~bH!$2  
        count=count+1 Vw&#
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    Wend .W\x{h  
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    'Set new shift in r#J_;P{U  
    op.Type = "ShiftZ" n<A<Xj08T9  
    op.val1 = taq ^--8 cLB n  
    op.parent = parID ;[:IC^9fv  
    AddOperation eID, op 6R#igLm  
    Print "Set aqueous humor thickness = " & taq-0.55 60xL.Z   
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    '************************************************************************* wF*9%K'E  
    'Radius and conic constant of anterior lens UhU"[^YO  
    '************************************************************************* =8Z-ORW51  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) #9HX"<5  
    GetConic eID, entity, curv, conic g6OPYUPg  
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    SetConic eID, entity, 1/Rant, CCant 7T(&DOGZ  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant S>s+ nqcP  
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    '************************************************************************* A(n3<(O/{Z  
    'Radius and conic constant of posterior lens >H,
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    '************************************************************************* sH%Ts@Pl  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) p?4,YV|#  
    GetConic eID, entity, curv, conic CsjrQ-#9yn  
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    SetConic eID, entity, 1/Rpost, CCpost ~,x4cOdR#  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost KppYe9?  
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    '************************************************************************* \GZ|fmYn  
    'Lens thickness (Position of posterior lens surface) nL]eGC  
    '************************************************************************* R.YUUXT  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) x-b}S1@  
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    ' Delete any z-shift(s) w,OPM}) il  
    count = 0
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    While GetOperationCount(eID)>count _SMi`ie#  
        GetOperation eID, count, op <00=bZzX  
        If op.Type="ShiftZ" Then tHr4/  
            DeleteOperation eID,count \:2z!\iP`  
            count=count-1 @c).&7  
        End If E *782>  
        count=count+1 O.{
  
    Wend |*l^<==  
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    'Set new z-shift J.]`l\

 
    op.Type = "ShiftZ" b)r;a5"<5  
    op.val1 = tlens n"@){:{4?  
    op.parent = parID Ny2bMj.o  
    AddOperation eID, op 3jHE,5m  
    Print "Set lens thickness = " & tlens uXb}oUC  
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    '************************************************************************* qI<c47d;q  
    'Lens index of refraction a;\a>N4  
    '************************************************************************* O,#,`2Qc  
    eID = FindMaterial( "Lens" ) Q(4~r+  
    GetModelMaterial eID, mat o[q|dhrANh  
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    mat.Nd = nlens U
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    SetModelMaterial eID, mat sH]T1z  
    Print "Set lens index of refraction = " & nlens ,V{Bpr  
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    '************************************************************************* [&(~1C|C  
    'Pupil diameter S>jOVWB  
    '************************************************************************* PzustC|  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) r~2q`l'>  
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    'Adjust pupil diameter (trimming volume inner hole) cg9*+]rc  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" }ktK*4<k  
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    ' Adjust pupil location to just in front of the lens N0N%~3  
    parID = FindFullName( "Geometry.Arizona Eye" ) qx*N-,M%k(  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 9WV8ZP  
    count = 0 hf;S#.k  
    While GetOperationCount(eID)>count sejT] rJ  
        GetOperation eID, count, op A=70
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        If op.Type="ShiftZ" Then ,$RXN8x1  
            DeleteOperation eID,count (0rcLNk{|  
            count=count-1 )}Cf6m}  
        End If O'QnfpQ*9  
        count=count+1 j,z)x[3}  
    Wend ?[%.4i;-h  
    op.Type = "ShiftZ" r>.l^U9hJ  
    op.val1 = taq-0.01 G&4D0f  
    op.parent = parID _xnJfW_  
    AddOperation eID, op 5'%O]~  
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    Print "Set pupil diameter = " & pupilDiam fuWAw^&  
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    'Update AZ Eye subassembly Description S"`{ JCW$  
    eID = FindFullName( "Geometry.Arizona Eye" ) ~RZN+N  
    GetEntity eID, entity bL{D*\HF  
    entity.Description = "Accommodation = " & A & "D" Ds{bYK_y  
    SetEntity eID, entity <vu~EY0.  
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    Update w{]B)>! 1W  
    Print "DONE!" ZZc^~  
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End Sub 3K/]{ dkD  
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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： i~*6JB|  
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Accommodation = 4 Diopters TJB4N$-}A  
Pupil Diameter = 4 mm ~{N#JOY}Z  
Set aqueous humor thickness = 2.81 UWdqcOr  
Set anterior lens radius = 10.4 and conic constant = -2.375869 `m$,8f%j6_  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 JIc9csr:b  
Set lens thickness = 3.927 `M-  
Set lens index of refraction = 1.42672 A5[kYD,_  
Set pupil diameter = 4 >y!O_@>z  
DONE! A{\DzUV9,  
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