[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 ]vyu!  
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。 >y2;sJ4]D%  
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模型 GwOn&EpY!  
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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。 2 kOFyD  
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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. +h64idM{U  
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光源 _f~(g1sE  
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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。 +<G |Ru-  
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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。 ){AtV&{$  
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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。 6@7K\${  
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视网膜的散射 dQ6n[$Q@N  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 (xp<@-  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。
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脚本 O/X;(qYd  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： p!+7F\  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 hK!Z~  
余下的脚本计算与屈光度有关的所有参数。 4?#0fK  
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分析 2?",2x09  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 *WSH-*0  
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脚本代码 r52X}Y  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. UbBo#(TZ)  
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Dim entity As T_ENTITY ]dXHjOpA  
Dim op As T_OPERATION omxBd#;F$  
Dim mat As T_MODELMATERIAL A),nkw0X  
Dim A As Double 2<dl23  
Dim pupilDiam As Double
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Dim eID As Long -29Sw  
Dim parID As Long .Y
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Dim count As Integer -Jo8jE~>V  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double jzuOs,:R  
Dim tlens As Double, nlens As Double CgLS2  
Dim curv As Double, conic As Double V:M$
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Dim ok As Long #z|\AmZ\  
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Sub Main 3xhv~be  
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    '用户输入对话框 :!omog  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ; Q-f6)+&  
        TextBox 220,21,40,21,.TextBox1 'default: 0 )P6n,\  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 o<`)cb }  
        OKButton 40,91,90,21 HaP0;9q  
        CancelButton 190,91,90,21 fV-vy]x..  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1
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        TextBox 220,49,40,21,.TextBox2 'default: 4 RB5fn+FiZ  
    End Dialog Evz;eobW/  
    Dim dlg As UserDialog 4<S*gu*W  

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    ok = Dialog (dlg) 'q
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    If ok=0 Then    'cancel button was pressed Oeo:
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        Print "Execution cancelled." )" H$1  
        End <1(:W[M  
    End If Zk+J=Cwq}  
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    'Assign accommodation and pupil diameter & use defaults if field left empty c#qOK  
    If dlg.TextBox1 = "" Then x4SI TY  
        A = 0           'Default accommodation *}9i@DP1,  
    Else yVThbL_YJ  
        A = CDbl(dlg.TextBox1) RjO9E.nm  
    End If P)fv:a  
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    If dlg.TextBox2 = "" Then '1)BZ!  
        pupilDiam = 4   'Default pupil diameter &"dT/5}6  
    Else Bp3%*va  
        pupilDiam = CDbl(dlg.TextBox2) *_<P%J  
    End If ^(ks^<}  
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    Print " " RUTlwT
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    Print "Accommodation = " & A & " Diopters" G"CV S@  
    Print "Pupil Diameter = " & pupilDiam & " mm" B;'Dh<J1
 
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    ' Calculate new parameters with accommodation {mPaloA  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness P5;LM9W  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens q #f U*  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens p*10u@,  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ,jWMJ0X/N=  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens T ,, Ao36  

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    tlens = 3.767 + 0.04*A                  'Lens thickness 73/kyu-0%  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction qvz2u]IOw  
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    'Adjust parameters to account for accommodation q!#e2Dx  
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    '************************************************************************* ScrEtN  
    'Aqueous thickness (Position of Lens) !Gu,X'#Ab  
    '************************************************************************* V\zf yH\~  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) `"v5bk  
    GetCustomElement eID, entity SCl$+9E  
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    parID = FindFullName( "Geometry.Arizona Eye" ) %dTkw+J  
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    ' Delete any shift(s) in z >=hOjV;  
    count = 0 )SZt If  
    While GetOperationCount(eID)>count i<|5~tm  
        GetOperation eID, count, op QRj><TKi  
        If op.Type="ShiftZ" Then ReOp,A/y  
            DeleteOperation eID,count "}UJ~ j).  
            count=count-1 \^iPU 27H  
        End If 27*u^N*z@  
        count=count+1 *>!O2c  
    Wend <@FOqi{o{  
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    'Set new shift in g(t"+ P  
    op.Type = "ShiftZ" Zam.g>{]  
    op.val1 = taq BP2-LG&\  
    op.parent = parID IM&2SSmYNH  
    AddOperation eID, op E"5 zT1d  
    Print "Set aqueous humor thickness = " & taq-0.55 U@+ @Mc  
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    '************************************************************************* gB@Xi*  
    'Radius and conic constant of anterior lens ~<Z;)e  
    '************************************************************************* {S(d5o8  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 6k
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    GetConic eID, entity, curv, conic 6_/691  
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    SetConic eID, entity, 1/Rant, CCant fk)ts,p?  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant I%^Ks$<"  
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    '************************************************************************* LtKiJ.j
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    'Radius and conic constant of posterior lens W HO;;j  
    '************************************************************************* {J q[N}  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) vlth\[  
    GetConic eID, entity, curv, conic DGr{x}Kq  
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    SetConic eID, entity, 1/Rpost, CCpost iph>"b$D
 
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost an^"_#8DA@  
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    '************************************************************************* /*g3TbUs  
    'Lens thickness (Position of posterior lens surface) `O(ec  
    '************************************************************************* O{a<f7 W  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) <b>
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    ' Delete any z-shift(s) . $uvQpyh  
    count = 0 LAeJz_9U  
    While GetOperationCount(eID)>count AEx I!  
        GetOperation eID, count, op }$3eRu +  
        If op.Type="ShiftZ" Then q}e"E cr  
            DeleteOperation eID,count aO('X3?  
            count=count-1 BL<
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        End If fv_}7t7  
        count=count+1 pkpD1c^  
    Wend V%'`nJ!  
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    'Set new z-shift | 2BIAm]  
    op.Type = "ShiftZ" W-q2|N
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    op.val1 = tlens RvKP&  
    op.parent = parID "l!WO`.zp=  
    AddOperation eID, op 
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    Print "Set lens thickness = " & tlens BJ!b LQ  
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    '************************************************************************* l CHaRR7  
    'Lens index of refraction SA&0f&07i  
    '************************************************************************* /e :V44  
    eID = FindMaterial( "Lens" ) A<l8CWv[  
    GetModelMaterial eID, mat Jm$.$B&I  
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    mat.Nd = nlens )z-)S  
    SetModelMaterial eID, mat 0xrr9X<  
    Print "Set lens index of refraction = " & nlens zbK=yOIOd  
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    '************************************************************************* u-PAi5&n  
    'Pupil diameter R>SS\YC'X  
    '************************************************************************* \Zz"%i  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) z+I'N4*^  
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    'Adjust pupil diameter (trimming volume inner hole) _O)xE9t#ru  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" C,7d  
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    ' Adjust pupil location to just in front of the lens _@9[c9bO  
    parID = FindFullName( "Geometry.Arizona Eye" ) WZO8|hY  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) `v3WJ>Q!N?  
    count = 0 ifj%!*   
    While GetOperationCount(eID)>count r!SMF]?SJ  
        GetOperation eID, count, op iSu7K&X9q  
        If op.Type="ShiftZ" Then x8k7y:
 
            DeleteOperation eID,count i'9aQi"G  
            count=count-1 7S$Am84%  
        End If xY9#ouF  
        count=count+1 |N_tVE  
    Wend 2g5i3C.q$  
    op.Type = "ShiftZ" |57u;  
    op.val1 = taq-0.01 +\g/KbV7  
    op.parent = parID 0JzH dz  
    AddOperation eID, op %@ UH,Ew  
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    Print "Set pupil diameter = " & pupilDiam ap=m5h27  
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    'Update AZ Eye subassembly Description 0$)s? \  
    eID = FindFullName( "Geometry.Arizona Eye" ) FsQeyh>  
    GetEntity eID, entity .j?`U[V%a  
    entity.Description = "Accommodation = " & A & "D" 873$EiyXR  
    SetEntity eID, entity O ]o7  
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    Update !/]F.0  
    Print "DONE!" :T^!<W4  
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End Sub -^sW{s0Rc  
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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： rk$&sDc/3  
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Accommodation = 4 Diopters "fK`F/  
Pupil Diameter = 4 mm {gh41G;n  
Set aqueous humor thickness = 2.81 Z9X<W`  
Set anterior lens radius = 10.4 and conic constant = -2.375869 aT}Mn(F*?  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 I5]=\k($  
Set lens thickness = 3.927 ldp x,  
Set lens index of refraction = 1.42672 S(NH# ^  
Set pupil diameter = 4 +8qtFog$\g  
DONE! ^b|Z<oF  
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