[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 HZm i?  
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。 A!D:Kc3  
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模型 1FJ[_l  
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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。 64lEB>VNm  
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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. ) b10%n^  
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光源 W,~1KUTc  
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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|lI=Q3f  
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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。 :#}`uR,D/  
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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。 ?~.&Y  
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视网膜的散射 ku?_/-ko]  
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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。 E5 oD|'=WA  
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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。 f'OvG@  
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脚本 LFyceFbm  
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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： 1omvE9 %zM  
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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。 j7#GqVS'  
余下的脚本计算与屈光度有关的所有参数。 5iddB $  
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分析 4D$sFR|?t  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 WgJAr73 l  
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脚本代码 G*i#\   
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. G.nftp(*}  
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Dim entity As T_ENTITY t* vg]Yc  
Dim op As T_OPERATION arS'th:j  
Dim mat As T_MODELMATERIAL C'/M/|=Q#  
Dim A As Double xg,]M/J  
Dim pupilDiam As Double yI.H4Dl<  
Dim eID As Long ZT"|o\G^
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Dim parID As Long <nTmZ-;  
Dim count As Integer WG/J4H`Od  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double V/}>>4  
Dim tlens As Double, nlens As Double #oJbrh9J6  
Dim curv As Double, conic As Double cJ##K/es  
Dim ok As Long ;Z1U@2./  
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Sub Main
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    '用户输入对话框 t9n  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Cxk$"_  
        TextBox 220,21,40,21,.TextBox1 'default: 0 !N8)C@=  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 {IPn\Bka  
        OKButton 40,91,90,21 &lPBqw  
        CancelButton 190,91,90,21 7s8<FyFsjd  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1  n22hVw  
        TextBox 220,49,40,21,.TextBox2 'default: 4 B_"OA3d_  
    End Dialog 4nII/cPG  
    Dim dlg As UserDialog R^yZG{?t  
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    ok = Dialog (dlg) ~"q,<t  
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    If ok=0 Then    'cancel button was pressed oIvnF:c  
        Print "Execution cancelled." cxD}t'T  
        End L);||]B  
    End If 7t-*L}~WA  
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    'Assign accommodation and pupil diameter & use defaults if field left empty [pW1=tI  
    If dlg.TextBox1 = "" Then -[=AlqL  
        A = 0           'Default accommodation oBj>9I;  
    Else I,<>%Z|'  
        A = CDbl(dlg.TextBox1) RZd4(7H=q  
    End If p_5>?[TW:  
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    If dlg.TextBox2 = "" Then X(!AI|6Bt  
        pupilDiam = 4   'Default pupil diameter hr
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    Else yF/< :  
        pupilDiam = CDbl(dlg.TextBox2) u3M`'YCb  
    End If <RoX|zJ
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    Print " " v$)@AE  
    Print "Accommodation = " & A & " Diopters" JMirz~%ib  
    Print "Pupil Diameter = " & pupilDiam & " mm" yL;o{ G  
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    ' Calculate new parameters with accommodation s3Krob`C5  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ;WvYzd9  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ?)?IZ Qj  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens KkdG.c'  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens !bZhj3.  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens r*i$+ Z  

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    tlens = 3.767 + 0.04*A                  'Lens thickness 'YZI>V*  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ^_*jp[!`b$  
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    'Adjust parameters to account for accommodation -7-Fd_F8  
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    '************************************************************************* j8[`~pb  
    'Aqueous thickness (Position of Lens) ]cF1c90%  
    '************************************************************************* W(uP`M%][0  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) VY+(,\)U  
    GetCustomElement eID, entity x{NNx:T1  
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    parID = FindFullName( "Geometry.Arizona Eye" ) c
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    ' Delete any shift(s) in z <qbZG}u  
    count = 0 Kk!6B  
    While GetOperationCount(eID)>count JCw{ ?^F"  
        GetOperation eID, count, op ;[{:'^n  
        If op.Type="ShiftZ" Then g.[+yzuE6  
            DeleteOperation eID,count Y<p zy8z  
            count=count-1 -
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        End If |8&-66pX  
        count=count+1 T!u'V'Ei2  
    Wend CRZi;7`*1  
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    'Set new shift in CrnB{Z4L  
    op.Type = "ShiftZ" CS~=Z>6EjA  
    op.val1 = taq 94T}iY.  
    op.parent = parID to99_2  
    AddOperation eID, op KWFyw>*)  
    Print "Set aqueous humor thickness = " & taq-0.55 Sk8%(
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    '************************************************************************* `fQM  
    'Radius and conic constant of anterior lens 'RDWU7c9]  
    '************************************************************************* La`h$=#`  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) IXGW2z;  
    GetConic eID, entity, curv, conic -M"IVyy@  
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    SetConic eID, entity, 1/Rant, CCant qTyg~]e9(  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant N=>- Q)  
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    '************************************************************************* x S  
    'Radius and conic constant of posterior lens iKg75%;t  
    '************************************************************************* 0Vf)Rw1%I  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 0-*Z<cu%l  
    GetConic eID, entity, curv, conic !+m@AQ:,  
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    SetConic eID, entity, 1/Rpost, CCpost ]}BB/KQy^  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost FQ+8J7  
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    '************************************************************************* (FM4 ^#6  
    'Lens thickness (Position of posterior lens surface) ,/~[S  
    '************************************************************************* YV*b~6{d  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) .j:i&j(  
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    ' Delete any z-shift(s) s>T`l  
    count = 0 2bWUa~%B  
    While GetOperationCount(eID)>count 3f_i1|>)'  
        GetOperation eID, count, op ]}'^`  
        If op.Type="ShiftZ" Then mRCHrw?WG  
            DeleteOperation eID,count rqF"QU=l  
            count=count-1 (G#}*  
        End If >&BrCu[u  
        count=count+1 H\ 3M  
    Wend ~NxEc8Y  
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    'Set new z-shift !;i*\ a  
    op.Type = "ShiftZ" .%_)*NUZ  
    op.val1 = tlens pqJ)G;%9  
    op.parent = parID Z #EvRC  
    AddOperation eID, op P2Onkl  
    Print "Set lens thickness = " & tlens CQ<8P86gt  
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    '************************************************************************* 0Su_#".-*  
    'Lens index of refraction %8 qSv%_  
    '************************************************************************* l1}R2lSEO  
    eID = FindMaterial( "Lens" ) Khj=llo,  
    GetModelMaterial eID, mat 3)y{n%
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    mat.Nd = nlens @.k5MOn  
    SetModelMaterial eID, mat ovz#  
    Print "Set lens index of refraction = " & nlens zHV|-R  
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    '************************************************************************* i-,'.w  
    'Pupil diameter C,.-Q"juH  
    '************************************************************************* ms7SoYbSu  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) h`lmC]X_  
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    'Adjust pupil diameter (trimming volume inner hole) 8
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" O] H=s  
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    ' Adjust pupil location to just in front of the lens z>|)ieL  
    parID = FindFullName( "Geometry.Arizona Eye" ) `dO}L  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) !y%+GwoW  
    count = 0 _jmkl B  
    While GetOperationCount(eID)>count 7G"7wYc>R  
        GetOperation eID, count, op odpUM@OAW  
        If op.Type="ShiftZ" Then -E]Sk&4Gj  
            DeleteOperation eID,count b_l3+'#ofM  
            count=count-1 ]H+{eJB7O  
        End If 0I @$ 0Gg  
        count=count+1 "J!}3)n  
    Wend {`F1u?l  
    op.Type = "ShiftZ" U*qNix  
    op.val1 = taq-0.01 -;>#3O-  
    op.parent = parID ib]vX-  
    AddOperation eID, op (z2Z)_6L*L  
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    Print "Set pupil diameter = " & pupilDiam 74_xR  
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    'Update AZ Eye subassembly Description O3Uh+gKQ  
    eID = FindFullName( "Geometry.Arizona Eye" ) qg4fR'
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    GetEntity eID, entity YjLe(+WQ  
    entity.Description = "Accommodation = " & A & "D" U CRAw3=  
    SetEntity eID, entity -`Q}tg>cT  
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    Update > :Ze4}(  
    Print "DONE!" DbtF~`3, .  
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End Sub g~!$i`_b  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： ^=0
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Accommodation = 4 Diopters _]=9#Fg7
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Pupil Diameter = 4 mm mM5|K@0|  
Set aqueous humor thickness = 2.81 /C$ xH@bb  
Set anterior lens radius = 10.4 and conic constant = -2.375869 aD ESr?  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 @]=f?+y[ 2  
Set lens thickness = 3.927 +9[SVw8  
Set lens index of refraction = 1.42672 :6lwO%=F  
Set pupil diameter = 4 s<&[\U  
DONE! gvyT-XI  
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