[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 :3f2^(b~^  
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。 L|LTsRIq  
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模型 9f\8oJQ  
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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。 37xxVbik  
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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. w|C~{  
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光源 +pvJ?"J  
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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。 fP58$pwu  
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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。 tHbPd.^  
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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。 OU@x1G{Cy  
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视网膜的散射 x-&v|w'  
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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。 ^z^e*<{WEl  
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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。 S7{.liHf  
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脚本 v&2@<I>  
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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： Aq%^>YAp  
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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。 8G&+  
余下的脚本计算与屈光度有关的所有参数。 GA.bRN2CI2  
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分析 I0+wczW,^  
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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。 F*t_lN5{  
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脚本代码 2BX GVo  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. C_cs(}wi  
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Dim entity As T_ENTITY =4<S8Cp  
Dim op As T_OPERATION [ 5 2zta  
Dim mat As T_MODELMATERIAL .*-w UBr  
Dim A As Double 9<h]OXv  
Dim pupilDiam As Double <W59mweW#5  
Dim eID As Long e ]o'i;I  
Dim parID As Long rn:zKTyhw  
Dim count As Integer \UqS -j|  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 4:&qTY)H  
Dim tlens As Double, nlens As Double HJaw\zbL  
Dim curv As Double, conic As Double a`b zFu{  
Dim ok As Long )|y2Q  
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Sub Main 6$s0-{^  
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    '用户输入对话框 cPsn]U  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 dMs||&|&  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ]]=fA 4(  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 =lC;^&D-0/  
        OKButton 40,91,90,21 M&/aJRBS  
        CancelButton 190,91,90,21 9/1+BQ  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ~,*YmB=Z  
        TextBox 220,49,40,21,.TextBox2 'default: 4 D"XX920$~  
    End Dialog ct}%Mdg  
    Dim dlg As UserDialog xD
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    ok = Dialog (dlg) AR~$MCR]"k  
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    If ok=0 Then    'cancel button was pressed PB(  
        Print "Execution cancelled." p/k<wCm6  
        End !Wixs]od   
    End If YYE8/\+B.  
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    'Assign accommodation and pupil diameter & use defaults if field left empty $HBT%g@UN  
    If dlg.TextBox1 = "" Then G_M:0YI@  
        A = 0           'Default accommodation Bhu@2KdA  
    Else xd|~+4  
        A = CDbl(dlg.TextBox1) )?B~64N,+  
    End If B3dA%\'  
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    If dlg.TextBox2 = "" Then & &" 'dL  
        pupilDiam = 4   'Default pupil diameter nx-1*  
    Else uKbHFF  
        pupilDiam = CDbl(dlg.TextBox2) w}j6.r  
    End If %l:|2s:  
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    Print " " PW*;Sp  
    Print "Accommodation = " & A & " Diopters" NFY|^*bll  
    Print "Pupil Diameter = " & pupilDiam & " mm" w53z*l>ek  
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    ' Calculate new parameters with accommodation 4@v1jJj  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Jh$"fr3  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens X a"XB  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens E7gHi$  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens #9$V 08  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens QB/7/PW{H\  
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    tlens = 3.767 + 0.04*A                  'Lens thickness $ZI~8rI~  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ?7yQ&p  
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    'Adjust parameters to account for accommodation ]*2EK9<  
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    '************************************************************************* -BA"3 S  
    'Aqueous thickness (Position of Lens) -DP8NTl"  
    '************************************************************************* IXZ(]&we
 
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) # 0GGc.  
    GetCustomElement eID, entity L$1K7<i.  
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    parID = FindFullName( "Geometry.Arizona Eye" ) x.b; +p}=  
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    ' Delete any shift(s) in z J>=1dCK  
    count = 0 +/y{^}b/  
    While GetOperationCount(eID)>count ytjK++(T5  
        GetOperation eID, count, op v"u7~Dw#1  
        If op.Type="ShiftZ" Then 7E$eN8H  
            DeleteOperation eID,count
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            count=count-1 ~ HK1X
  
        End If of8mwnZR  
        count=count+1 3`58ah  
    Wend Z-(} l2\  
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    'Set new shift in ~J0,)_b%*  
    op.Type = "ShiftZ" n{dP@_>WS  
    op.val1 = taq S dIGU[fm  
    op.parent = parID W|
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    AddOperation eID, op "r8EC  
    Print "Set aqueous humor thickness = " & taq-0.55 +0]'| tF>  
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    '************************************************************************* :T_'
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    'Radius and conic constant of anterior lens m!<X8d[bD  
    '************************************************************************* $^}[g9]1  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) LeY+p]n~  
    GetConic eID, entity, curv, conic Rcg
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    SetConic eID, entity, 1/Rant, CCant 4P|$LkI  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ZB828T3  
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    '************************************************************************* bE?'C h  
    'Radius and conic constant of posterior lens uie~'K\y  
    '************************************************************************* %a5t15 9  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) On=u#DxQ  
    GetConic eID, entity, curv, conic dM Y 0K  
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    SetConic eID, entity, 1/Rpost, CCpost 9b1?W?"  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost cVp[ Z#B  
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    '************************************************************************* R|iEv
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    'Lens thickness (Position of posterior lens surface) m}98bw  
    '************************************************************************* "K,bH  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) F\5X7ditD  

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    ' Delete any z-shift(s) P/ci/y_1  
    count = 0 R'SBd}1  
    While GetOperationCount(eID)>count 6O9iEc,HM  
        GetOperation eID, count, op !\^jt%e&  
        If op.Type="ShiftZ" Then {LP b))  
            DeleteOperation eID,count 4r\
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            count=count-1 t05_Px!mW  
        End If SBTPTb  
        count=count+1 KbAR_T1n  
    Wend mzGjRl=O  
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    'Set new z-shift 0#QKVZq2>  
    op.Type = "ShiftZ" 7{pIPmJ  
    op.val1 = tlens #$FrFU;ZR  
    op.parent = parID !6HuFf  
    AddOperation eID, op g<$. - g  
    Print "Set lens thickness = " & tlens 3?2<WEYr  
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    '************************************************************************* qe$33f*  
    'Lens index of refraction !EOQhh  
    '************************************************************************* r| f-_D  
    eID = FindMaterial( "Lens" ) MTb,Kmw<(  
    GetModelMaterial eID, mat g:_hj_1Y M  
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    mat.Nd = nlens d ;^  
    SetModelMaterial eID, mat bKMWWJf*'  
    Print "Set lens index of refraction = " & nlens RNTa XR+Zn  
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    '************************************************************************* >7'+ye6z  
    'Pupil diameter */w7?QOv  
    '************************************************************************* xvmt.
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Q(Gyq:L=>  
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    'Adjust pupil diameter (trimming volume inner hole) ]tB@kBi "  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder"
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    ' Adjust pupil location to just in front of the lens q8>t!rh<R  
    parID = FindFullName( "Geometry.Arizona Eye" ) 5qbq,#Pf  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ;~+]! U  
    count = 0 *0y{ ~@  
    While GetOperationCount(eID)>count Kb&V!#o)  
        GetOperation eID, count, op <sX VW  
        If op.Type="ShiftZ" Then j13DJ.xu  
            DeleteOperation eID,count !`&\Lx_  
            count=count-1 \\:|Odd  
        End If -\#lF?fzb  
        count=count+1 f+x;:  
    Wend @g-G =Ba  
    op.Type = "ShiftZ" =dzWmL<~8  
    op.val1 = taq-0.01 >2b`\Q*<  
    op.parent = parID xJc$NV-JzK  
    AddOperation eID, op raE Mm  
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    Print "Set pupil diameter = " & pupilDiam FW..mD9)}  
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    'Update AZ Eye subassembly Description SV.z>p  
    eID = FindFullName( "Geometry.Arizona Eye" ) :,S98
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    GetEntity eID, entity ])w[

  
    entity.Description = "Accommodation = " & A & "D" /_t|Dry015  
    SetEntity eID, entity \X|sU:g  
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    Update RWKH%C[Yd  
    Print "DONE!" kWhr1wR1  
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End Sub
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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： "Sridh?  
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Accommodation = 4 Diopters ~"K,7sw!Y  
Pupil Diameter = 4 mm
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Set aqueous humor thickness = 2.81 pOT7;-#n  
Set anterior lens radius = 10.4 and conic constant = -2.375869 "6CMA0R  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 DinPxtT?a  
Set lens thickness = 3.927 Ps4 ZFX  
Set lens index of refraction = 1.42672 lv%9MW0 z  
Set pupil diameter = 4 xY<{qHcX  
DONE! Y32 "N[yw  
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