[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 DwQaj"1<%  
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。 K?y!zy  
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模型 qU'O4TWZ  
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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。 rA*"22v=  
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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. &DqeO8?Q  
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光源 UUxDW3K  
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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。 x*)@:W!  
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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。 R+c  {Pl  
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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。 'xO^2m+N;  
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视网膜的散射 _&/FO{F@m  
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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。 ODGOWw0  
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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。 EDm,Y  
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脚本 |eEcEu?/b  
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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： 3^>D |  
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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。 FFTh}>>  
余下的脚本计算与屈光度有关的所有参数。 ]jUxL=]r  
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分析 wIW]uo/=  
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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。 Q\H_lB  
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脚本代码 kfF.Ctr1a  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. yNk9KK)  
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Dim entity As T_ENTITY <y+8\m  
Dim op As T_OPERATION 4\%0a,\^  
Dim mat As T_MODELMATERIAL MQR@(>TZy  
Dim A As Double i,=CnZCh  
Dim pupilDiam As Double ^Zh YW  
Dim eID As Long &n% 3rC5{  
Dim parID As Long kan?2x  
Dim count As Integer ;cBFft}D  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double LbGyD;#_  
Dim tlens As Double, nlens As Double Q3SwW  
Dim curv As Double, conic As Double 'F'v/G~
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Dim ok As Long UR~9*`Z ,  
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Sub Main "{0 o"k  
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    '用户输入对话框 &H!#jh\w  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 *g$egipfF  
        TextBox 220,21,40,21,.TextBox1 'default: 0 :@6,|2be=  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 '-F }(9M  
        OKButton 40,91,90,21 neGCMKtzlJ  
        CancelButton 190,91,90,21 $I%75IZ  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 &lYZ=|6  
        TextBox 220,49,40,21,.TextBox2 'default: 4 x\vb@!BZ  
    End Dialog D.2HM  
    Dim dlg As UserDialog B]K@'#  
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    ok = Dialog (dlg) NGHzifaE   


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    If ok=0 Then    'cancel button was pressed Z9rs,_A  
        Print "Execution cancelled." CVsc#=w0  
        End N@UO8'"9K&  
    End If ,c:Fa)-  
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    'Assign accommodation and pupil diameter & use defaults if field left empty yQ> *F  
    If dlg.TextBox1 = "" Then
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        A = 0           'Default accommodation n237%LH[  
    Else 6aG/=fq  
        A = CDbl(dlg.TextBox1) pPcn F`A  
    End If ms'!E)  
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    If dlg.TextBox2 = "" Then Y?Yix  
        pupilDiam = 4   'Default pupil diameter kI974:e42  
    Else 6g@@V=mf  
        pupilDiam = CDbl(dlg.TextBox2) jP6;~[rl  
    End If }SHF  
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    Print " " v>TI.;{y  
    Print "Accommodation = " & A & " Diopters" 3Q^@!hu  
    Print "Pupil Diameter = " & pupilDiam & " mm" h5
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    ' Calculate new parameters with accommodation Do}mCv  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness y 1fl=i  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ': Gk~   
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens FJ3Xeos4|  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens SE+K"faKQ  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens x
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    tlens = 3.767 + 0.04*A                  'Lens thickness B[^mWVp6L  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction S86%o,Saq\  
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    'Adjust parameters to account for accommodation @RKw1$BA  
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    '************************************************************************* vB, X)  
    'Aqueous thickness (Position of Lens) ;p%a!Im_<  
    '************************************************************************* ?\:ysTVu  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) |MvCEp  
    GetCustomElement eID, entity G0$ 1"9u\w  
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    parID = FindFullName( "Geometry.Arizona Eye" ) Y3jb'S4(  
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    ' Delete any shift(s) in z OL*EY:]  
    count = 0 "(ehf|%>%  
    While GetOperationCount(eID)>count -\yaP8V  
        GetOperation eID, count, op _$"qC[.  
        If op.Type="ShiftZ" Then @)iv'  
            DeleteOperation eID,count -nG3(n&wB  
            count=count-1 S~`&K  
        End If MId\dFu  
        count=count+1 %(b`i C9  
    Wend <'QHe4  
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    'Set new shift in xmZ]mu,,$  
    op.Type = "ShiftZ" C^RO@kM  
    op.val1 = taq mfLS</A  
    op.parent = parID 4O[T:9mn0  
    AddOperation eID, op RL
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    Print "Set aqueous humor thickness = " & taq-0.55 )` S,vF~  
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    '************************************************************************* r: n^U#  
    'Radius and conic constant of anterior lens XXacWdh \  
    '************************************************************************* 3/o-\wWO  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) kc `Q- N}  
    GetConic eID, entity, curv, conic ptGM'  
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    SetConic eID, entity, 1/Rant, CCant he&*N*of:  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant XbYW,a@w2  
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    '************************************************************************* d$g-u8  
    'Radius and conic constant of posterior lens %WHue  
    '************************************************************************* yL&F!+(/Ix  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) N5[QQtQ  
    GetConic eID, entity, curv, conic <LQwH23@  
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    SetConic eID, entity, 1/Rpost, CCpost Z<z(;)?c  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost o6K\z+.{  
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    '************************************************************************* %1a\"F![  
    'Lens thickness (Position of posterior lens surface) CD%wi:C%|  
    '************************************************************************* QNzI  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) mYXe0E#6  
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    ' Delete any z-shift(s) 2J9_(w  
    count = 0 X'e@(I!0  
    While GetOperationCount(eID)>count PoY+Y3  
        GetOperation eID, count, op i3s-l8\\z  
        If op.Type="ShiftZ" Then bl(rCbj(w  
            DeleteOperation eID,count UyBI;k^]  
            count=count-1 >Rs:Fw|jro  
        End If \kZxys!4  
        count=count+1 5E?{>1  
    Wend phwk0J]2  
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    'Set new z-shift 5`*S'W}\>  
    op.Type = "ShiftZ" ([iMOE[D3  
    op.val1 = tlens mu0
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    op.parent = parID 4StiY
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    AddOperation eID, op ,95Nj h  
    Print "Set lens thickness = " & tlens _/MHi-]/.  
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    '************************************************************************* ^tIs57!  
    'Lens index of refraction p ElF,Y  
    '************************************************************************* U-#wFc2N  
    eID = FindMaterial( "Lens" ) ?kX$Y{M}  
    GetModelMaterial eID, mat ".onev^(  
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    mat.Nd = nlens a,x-akZWf  
    SetModelMaterial eID, mat u)y6$  
    Print "Set lens index of refraction = " & nlens i-~HT4iw  
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    '************************************************************************* qk{2%,u$@{  
    'Pupil diameter Z{xm(^'i  
    '************************************************************************* rg)>ZHx  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) nAG2!2_8  
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    'Adjust pupil diameter (trimming volume inner hole) SwpS6  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" d4t%/Uh  
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    ' Adjust pupil location to just in front of the lens e<6fe-g9;  
    parID = FindFullName( "Geometry.Arizona Eye" ) "C&l7K;bp  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) XCCN6[[+  
    count = 0 <43O,Kx'Su  
    While GetOperationCount(eID)>count 1[OCojo<  
        GetOperation eID, count, op W2P(!q>r]  
        If op.Type="ShiftZ" Then r) ;U zd  
            DeleteOperation eID,count Y^Y|\0  
            count=count-1 Xd@  -  
        End If c+,F)i^`  
        count=count+1 b^_#f:_j
 
    Wend AX,V* s  
    op.Type = "ShiftZ" Q^>"AhOiU  
    op.val1 = taq-0.01 X|fl_4NC>  
    op.parent = parID ?j9J6=2  
    AddOperation eID, op #kjN!S*=  
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    Print "Set pupil diameter = " & pupilDiam *UhYX)J  
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    'Update AZ Eye subassembly Description `w';}sQA7  
    eID = FindFullName( "Geometry.Arizona Eye" ) Vw:.'-Oi  
    GetEntity eID, entity T1 >xw4uo  
    entity.Description = "Accommodation = " & A & "D" #pO=\lJ
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    SetEntity eID, entity k/o"E  
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    Update L"{qF<@V7&  
    Print "DONE!" >uT,Z,7O  
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End Sub ~Gm<F .(+  
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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： KtTv0[66  
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Accommodation = 4 Diopters
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Pupil Diameter = 4 mm BBuI|lr  
Set aqueous humor thickness = 2.81 `u6CuH
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Set anterior lens radius = 10.4 and conic constant = -2.375869 dZ}gf}.v  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 " O0p.o  
Set lens thickness = 3.927 d1]CN6 7{G  
Set lens index of refraction = 1.42672 2q]y(kW+  
Set pupil diameter = 4 VZuluV  
DONE! PJ}d- 
 
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