[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 s!esk%h{K  
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。 55MrsiW  
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模型 o^hI\9  
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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。 4nQk*:p(X  
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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. =QFnab?N  
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光源 *{8<4CVv  
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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。 2?9 FFlX  
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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。 M24FuS  
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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。 J0CEZ  
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视网膜的散射 qI;"yG-x-  
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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。 )';Rb$<Qn  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 5ws|4V  
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脚本 qOy3D~  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： ?O(KmDH  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 gI8r SmH  
余下的脚本计算与屈光度有关的所有参数。 V ;Kzh$^rk  
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分析 d'ddxT$GG  
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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。 'PPVM@)fU  
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脚本代码 ~XAtt\WS  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 9Fb|B  
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Dim entity As T_ENTITY Zwy8SD'L  
Dim op As T_OPERATION [P,YW|:n  
Dim mat As T_MODELMATERIAL Hik8u!#P  
Dim A As Double n+Ofbiz@  
Dim pupilDiam As Double l{oAqTN  
Dim eID As Long /3|uU  
Dim parID As Long sVP[7&vr~  
Dim count As Integer 3=o^Vv  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double i!8 o(!I  
Dim tlens As Double, nlens As Double 
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Dim curv As Double, conic As Double XQC
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Dim ok As Long |Y'xtOMX  
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Sub Main #N%ATV  
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    '用户输入对话框 6<0-GD}M  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 9_Tk8L#  
        TextBox 220,21,40,21,.TextBox1 'default: 0 VsS.\1  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 bz!9\D|h  
        OKButton 40,91,90,21 Co6ghH7T  
        CancelButton 190,91,90,21 (I3:u-A  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +zodkB~)  
        TextBox 220,49,40,21,.TextBox2 'default: 4 vd7%#sHH&  
    End Dialog (?MRbX]@  
    Dim dlg As UserDialog +N0V8T%~z.  
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    ok = Dialog (dlg) S"?py=7  
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    If ok=0 Then    'cancel button was pressed oXw}K((|  
        Print "Execution cancelled." Ao%E]M  
        End :x e/7
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    End If pT Yq#9  
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    'Assign accommodation and pupil diameter & use defaults if field left empty Jp)>Wd  
    If dlg.TextBox1 = "" Then bA]/p%rZ8  
        A = 0           'Default accommodation &.k'Dj2hf  
    Else MGn:Gj"d  
        A = CDbl(dlg.TextBox1) KQsS)ju  
    End If 4ujw/`:/m  
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    If dlg.TextBox2 = "" Then `q Sfo`  
        pupilDiam = 4   'Default pupil diameter sW%U3,j  
    Else [\N,ow,n  
        pupilDiam = CDbl(dlg.TextBox2) 1_vaSEov  
    End If 9vc3&r  
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    Print " " SF*!Z2K  
    Print "Accommodation = " & A & " Diopters" <p<jXwl  
    Print "Pupil Diameter = " & pupilDiam & " mm" h>B>t/k?  
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    ' Calculate new parameters with accommodation <d$kGCz  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness | >xUgpQi  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens S!gV\gEbDj  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 75vd ]45as  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens k#k!AcC  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens F?2(U\k#  
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    tlens = 3.767 + 0.04*A                  'Lens thickness }vBk,ED  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction \~ O6S`,  
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    'Adjust parameters to account for accommodation pE>~F  
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    '************************************************************************* $?p^ m`t_  
    'Aqueous thickness (Position of Lens) 061@N=p8  
    '************************************************************************* *,1^{mb  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ]D&$k P(  
    GetCustomElement eID, entity fx|$(D@9  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 2!/*I:  
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    ' Delete any shift(s) in z mMO:m8W  
    count = 0 rly3f  
    While GetOperationCount(eID)>count 2&fIF}vk>m  
        GetOperation eID, count, op -[OGZP`8  
        If op.Type="ShiftZ" Then N,|:=gD_  
            DeleteOperation eID,count Y}(#kqh>  
            count=count-1 '/ 3..3k  
        End If eG
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        count=count+1 Ty\&ARjb 8  
    Wend 'LIJpk3J  
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    'Set new shift in s9) @$3\  
    op.Type = "ShiftZ" [>#?C*s  
    op.val1 = taq Mvoi   
    op.parent = parID M=n!tVlCV  
    AddOperation eID, op $A6'YgK  
    Print "Set aqueous humor thickness = " & taq-0.55 g<oSTAw  
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    '************************************************************************* hX\XNiCiK8  
    'Radius and conic constant of anterior lens EL80f>K  
    '************************************************************************* 1R9hA7y&,/  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) e#IED!U  
    GetConic eID, entity, curv, conic l epR}  
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    SetConic eID, entity, 1/Rant, CCant LKY4rY!|@d  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant {6'5K U*RH  
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    '************************************************************************* nU%rSASu  
    'Radius and conic constant of posterior lens [>&Nhn0iY  
    '************************************************************************* _={*<E  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) @P+k7"f  
    GetConic eID, entity, curv, conic 2H fP$.  
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    SetConic eID, entity, 1/Rpost, CCpost Y>Q9?>
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost yd5r]6ej  
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    '************************************************************************* vjaIFyj  
    'Lens thickness (Position of posterior lens surface) i%>]$*  
    '************************************************************************* orf21N+[  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" )  f]q3E[?/  
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    ' Delete any z-shift(s) Zu:cF+hl  
    count = 0 i}ypEp  
    While GetOperationCount(eID)>count 9I=J#Hi|+  
        GetOperation eID, count, op hJ#U;
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        If op.Type="ShiftZ" Then gt6*x=RCrQ  
            DeleteOperation eID,count :^lyVQ%@  
            count=count-1 QsI#Ae,O#;  
        End If EaFd1  
        count=count+1 @^} % o-:  
    Wend %k{~Fa  
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    'Set new z-shift cH'*J/  
    op.Type = "ShiftZ" :h0as!2@dp  
    op.val1 = tlens  IPa08/  
    op.parent = parID neJNMdv@T  
    AddOperation eID, op ;r>?V2,tm  
    Print "Set lens thickness = " & tlens =|S8.|r+  
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    '************************************************************************* -% PUY(  
    'Lens index of refraction kmNY ;b6Y$  
    '************************************************************************* Y}'C'PR  
    eID = FindMaterial( "Lens" ) Tz+2g&+  
    GetModelMaterial eID, mat I>bLgt]u3  
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    mat.Nd = nlens %~J90a  
    SetModelMaterial eID, mat n'73DApW  
    Print "Set lens index of refraction = " & nlens +cM;d4  
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    '************************************************************************* W"AWhi{h  
    'Pupil diameter KM< +9`  
    '************************************************************************* $&EZVZ{r  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) r^_8y8&l  
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    'Adjust pupil diameter (trimming volume inner hole) {o+aEMhM  

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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 9c9-1iS  
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    ' Adjust pupil location to just in front of the lens T,Cq;|g5E  
    parID = FindFullName( "Geometry.Arizona Eye" ) U}MU>kzb  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) +`u]LOAyP=  
    count = 0 468LVe?0  
    While GetOperationCount(eID)>count 'IFbD["r  
        GetOperation eID, count, op ?`AzgM[I  
        If op.Type="ShiftZ" Then qi`*4cas*A  
            DeleteOperation eID,count djqSW9  
            count=count-1 Run)E*sf  
        End If s2_j@k?%  
        count=count+1 ~^$ONmI
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    Wend \K`AO{ D@  
    op.Type = "ShiftZ" 4otB1{  
    op.val1 = taq-0.01 *'`ByS  
    op.parent = parID z 4Qz9#*"^  
    AddOperation eID, op !sEI|
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    Print "Set pupil diameter = " & pupilDiam x
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    'Update AZ Eye subassembly Description !w]!\H  
    eID = FindFullName( "Geometry.Arizona Eye" ) WTA0S}pT  
    GetEntity eID, entity 91E!4t
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    entity.Description = "Accommodation = " & A & "D" U|g4t=@ZR  
    SetEntity eID, entity kR7IZo"q  

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    Update Zg5@l3w  
    Print "DONE!" |Q`}a %  
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End Sub y^Oj4Y:  
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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： eg~$WB;1  
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Accommodation = 4 Diopters [X
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Pupil Diameter = 4 mm DGO_fR5L  
Set aqueous humor thickness = 2.81 g}{Rk>
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Set anterior lens radius = 10.4 and conic constant = -2.375869 ,(N&%  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 3T# zxu  
Set lens thickness = 3.927 BqvOi~l  
Set lens index of refraction = 1.42672 Lx8^V7X  
Set pupil diameter = 4 uKo)iB6D  
DONE! r&A#h;EQX2  
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