[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 Vp|2wlFE-  
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。 Cq-hPa}2  
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模型 +G<}JJ'V  
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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。 Cw6>^  
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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. d&/^34gn  
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光源 UAnB=L,.\  
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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。 @~JB\j9  
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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。 X(4s;i  
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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。 7xX;MB&  
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视网膜的散射 }rO?5  
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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。 RpBiE8F4  
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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。 t#fs:A7P?}  
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脚本 L~@ma(TV{K  
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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： \4[c}l  
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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。 TYs+XJ'Xj  
余下的脚本计算与屈光度有关的所有参数。 Q%M'[L?[  
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分析 <_##YSGh,  
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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。 Ha46U6_'h  
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脚本代码 Y|{r vBKjf  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. '5|Q<5!o  
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Dim entity As T_ENTITY I-RdAVB/Ep  
Dim op As T_OPERATION zWCW:dI  
Dim mat As T_MODELMATERIAL tc+GR?-7W  
Dim A As Double ga4/,   
Dim pupilDiam As Double (z8]FT  
Dim eID As Long -/(DPx  
Dim parID As Long 3q~":bpAp  
Dim count As Integer Q3<bC6$r  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Y9IJ  
Dim tlens As Double, nlens As Double t9Enk!@  
Dim curv As Double, conic As Double %NF<bEV  
Dim ok As Long =oL8d6nI  
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Sub Main |i,zY{GI+2  
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    '用户输入对话框 nx!qCgo  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 =:xV(GK}  
        TextBox 220,21,40,21,.TextBox1 'default: 0 2*~JMbm  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 R-r+=x&  
        OKButton 40,91,90,21 %Y)PH-z  
        CancelButton 190,91,90,21 Zu2m%=J`  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 fZka%[B  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ?$"x^=te7  
    End Dialog Hrd5p+j  
    Dim dlg As UserDialog jRv;D#Hp  
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    ok = Dialog (dlg) ^%K1R;  
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    If ok=0 Then    'cancel button was pressed lfU"SSQ  
        Print "Execution cancelled." Z^/z  
        End G"T;l"TAt8  
    End If gmF_~"^34  
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    'Assign accommodation and pupil diameter & use defaults if field left empty <;$Sa's,LE  
    If dlg.TextBox1 = "" Then <r_P? lZW  
        A = 0           'Default accommodation I2t-D1X  
    Else 1=9qAp;?o  
        A = CDbl(dlg.TextBox1) OCbQB5k3  
    End If UA69_E{JCH  
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    If dlg.TextBox2 = "" Then rQd1Ch  
        pupilDiam = 4   'Default pupil diameter Jf%!I  
    Else dvg;  
        pupilDiam = CDbl(dlg.TextBox2) mr{k>Un\  
    End If ++J Bbuzj!  
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    Print " " ZXssvjWQV}  
    Print "Accommodation = " & A & " Diopters" [3{:H"t  
    Print "Pupil Diameter = " & pupilDiam & " mm" )o " SB1  
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    ' Calculate new parameters with accommodation _H^^2#wc/  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ),D`ZRXS  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ohQz%?r  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 0,vj,ic*WX  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens F- !}
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens zn2"swhq\V  
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    tlens = 3.767 + 0.04*A                  'Lens thickness MYDf`0{$_a  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction M/8#&RycQ  
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    'Adjust parameters to account for accommodation =\Tud-1Z  
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    '************************************************************************* Gg}LC+Y  
    'Aqueous thickness (Position of Lens) =B/s HN  
    '************************************************************************* gNEzl
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    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) w{YtTZp3  
    GetCustomElement eID, entity cdek^/  
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    parID = FindFullName( "Geometry.Arizona Eye" ) (04j4teE  
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    ' Delete any shift(s) in z ~u?x{[  
    count = 0 A3 Rm0  
    While GetOperationCount(eID)>count W{$+mow7S  
        GetOperation eID, count, op FM;;x(sg  
        If op.Type="ShiftZ" Then TeGLAt  
            DeleteOperation eID,count 3-9J"d!  
            count=count-1 xyz\;
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        End If \J3v>&m<7  
        count=count+1 ys.!S.k+  
    Wend %`s9yRk9>E  
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    'Set new shift in }'w^<:RSy  
    op.Type = "ShiftZ" P5 <85t  
    op.val1 = taq qs8K jG@  
    op.parent = parID x%:>Ol  
    AddOperation eID, op x w?9W4<  
    Print "Set aqueous humor thickness = " & taq-0.55 a`h$lUb-  
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    '*************************************************************************  h>L6{d1  
    'Radius and conic constant of anterior lens [r/Seg"  
    '************************************************************************* JI[rIL\Ey  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) fbx;-He!  
    GetConic eID, entity, curv, conic +poIgjq0  
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    SetConic eID, entity, 1/Rant, CCant ++p& x{  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant %.6?\w1e  
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    '************************************************************************* 9^Vx*KVrU  
    'Radius and conic constant of posterior lens d,Dg"Z  
    '************************************************************************* c;t(j'k`  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) )Ido|!]0d  
    GetConic eID, entity, curv, conic \'^Z_6{w  
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    SetConic eID, entity, 1/Rpost, CCpost NM.f0{:cj  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost k`4\.m"&  
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    '************************************************************************* $O]E$S${  
    'Lens thickness (Position of posterior lens surface) #35S7G^@`  
    '************************************************************************* L&gEQDPgq|  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ?BWvF]p5/  
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    ' Delete any z-shift(s) OHtZ"^YG  
    count = 0 [>]VN)_J5  
    While GetOperationCount(eID)>count '`goy%Wd  
        GetOperation eID, count, op b8b PK<  
        If op.Type="ShiftZ" Then :PjUl  
            DeleteOperation eID,count $d??(  
            count=count-1 e[k;SSs  
        End If 2DBFXhP  
        count=count+1 pt|$bU7  
    Wend ~PAbLSL*u  
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    'Set new z-shift 4oaP"T@6  
    op.Type = "ShiftZ" ,
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    op.val1 = tlens v%8-Al^G  
    op.parent = parID y@8399;l  
    AddOperation eID, op +uGP(ONY  
    Print "Set lens thickness = " & tlens #y9K-}u  
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    '************************************************************************* I3[RaZ2z{  
    'Lens index of refraction +fQ$~vr{'  
    '************************************************************************* Ug'nr  
    eID = FindMaterial( "Lens" ) LAVt/TcZS|  
    GetModelMaterial eID, mat "s6_lhu=E7  
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    mat.Nd = nlens ;51!aC  
    SetModelMaterial eID, mat eEZlVHM;O  
    Print "Set lens index of refraction = " & nlens md +`#-D\O  
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    '*************************************************************************  F-\8f(\  
    'Pupil diameter z^HlDwsbm  
    '************************************************************************* P;91C'T-x  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Qc<O; #  
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    'Adjust pupil diameter (trimming volume inner hole) iuk8c.TAR  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 2F@<{
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    ' Adjust pupil location to just in front of the lens mt]YY<l  
    parID = FindFullName( "Geometry.Arizona Eye" ) L$?~TY  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) iwTBE]J  
    count = 0 $mg h.3z0  
    While GetOperationCount(eID)>count z)y(31K<1  
        GetOperation eID, count, op \
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        If op.Type="ShiftZ" Then 9v3N
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            DeleteOperation eID,count MJR\ g3  
            count=count-1 "&o@%){]  
        End If 5<8>G?Y  
        count=count+1 <@ex})su  
    Wend CbaAnm1  
    op.Type = "ShiftZ" ^ J@i7FOb  
    op.val1 = taq-0.01 90696v.

 
    op.parent = parID "1TM  
    AddOperation eID, op I:)#U[tn0  
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    Print "Set pupil diameter = " & pupilDiam WjxB
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    'Update AZ Eye subassembly Description \bmboNe  
    eID = FindFullName( "Geometry.Arizona Eye" ) ^ /eSby  
    GetEntity eID, entity Ps5wQaS  
    entity.Description = "Accommodation = " & A & "D" NW Qu-]P  
    SetEntity eID, entity UdgI<a~`k6  
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    Update ]`U?<9~Ob  
    Print "DONE!" 1,D ^,  
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End Sub d"uM7PMs7x  
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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： ,(?4T
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Accommodation = 4 Diopters v"TH[}C9D  
Pupil Diameter = 4 mm xH-k~#  
Set aqueous humor thickness = 2.81 2*E<G|-F  
Set anterior lens radius = 10.4 and conic constant = -2.375869 K4L#%KUPW  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 R.$Y1=U6  
Set lens thickness = 3.927 e
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Set lens index of refraction = 1.42672 UsKn4Kh  
Set pupil diameter = 4 5 :>  
DONE! *3oQS"8  
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