[分享]Arizona眼睛模型 [复制链接]

简介 Vzrp9&loY  
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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。 bF3}L=z  
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模型 gJn_8\,C>Q  
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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。
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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. +Y^/0=6h  
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光源 Yyh X%S%  
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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。 G0h7MO%x  
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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。 3m`y?Dd  
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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。 gTP0:  
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视网膜的散射 wg,w;Gle  
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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。 -5yEd>Z  
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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。 &P{[22dQ  
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脚本 #}!Ge  
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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： H6XlS
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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。 %<8lLRl  
余下的脚本计算与屈光度有关的所有参数。 l;SqjkN  
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分析 v9OK <  
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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。 R"=pAO.4l  
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脚本代码 E(oI0*S.5  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. }Z_w8+BZ  
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Dim entity As T_ENTITY PSQ5/l?\>  
Dim op As T_OPERATION j9YI6X"  
Dim mat As T_MODELMATERIAL *s9 +  
Dim A As Double >I3#ALF  
Dim pupilDiam As Double ayJKt03\O\  
Dim eID As Long $!x8XpR8s  
Dim parID As Long L= fz:H  
Dim count As Integer :YU_ \EV  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double C0X_t  
Dim tlens As Double, nlens As Double q]Cm
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Dim curv As Double, conic As Double V\"x
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Dim ok As Long &!#a^d+` 0  
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Sub Main %klC& _g~_  
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    '用户输入对话框 9air"4  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 S3u>a\  
        TextBox 220,21,40,21,.TextBox1 'default: 0 DDT)l+:XP  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 \4`~J@5Y  
        OKButton 40,91,90,21 '@h
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        CancelButton 190,91,90,21 CCOd4  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 2Ke?*  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ^|?/ y=  
    End Dialog 8M;VX3
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    Dim dlg As UserDialog vJT %ET  
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    ok = Dialog (dlg) S$Tc\/{  
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    If ok=0 Then    'cancel button was pressed Y=l91dxGI  
        Print "Execution cancelled." s('<ms  
        End t8,s]I&  
    End If J)iy6{0"  
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    'Assign accommodation and pupil diameter & use defaults if field left empty {1.t ZCMT  
    If dlg.TextBox1 = "" Then #`rvL6W q}  
        A = 0           'Default accommodation oO-kO!59y  
    Else ^<#08L;  
        A = CDbl(dlg.TextBox1) 7yLO<o?9w  
    End If 8S[`(] )  
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    If dlg.TextBox2 = "" Then (-tF=wR,W  
        pupilDiam = 4   'Default pupil diameter 1CFTQB>  
    Else &{?*aK&%3l  
        pupilDiam = CDbl(dlg.TextBox2) y{ReQn3>y  
    End If  &y/  
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    Print " " ^~k2(DLk  
    Print "Accommodation = " & A & " Diopters" P)Vm4u 1  
    Print "Pupil Diameter = " & pupilDiam & " mm" %Ji@\|Zkf  
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    ' Calculate new parameters with accommodation !j,LS$tPu  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness T> cvV  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens fJ_d,4  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens p.kJNPO\@  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens KiU/N$E  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens <\<[J0  
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    tlens = 3.767 + 0.04*A                  'Lens thickness '`$z!rA  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction bLyU;  
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    'Adjust parameters to account for accommodation }=CL/JHz  
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    '*************************************************************************
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    'Aqueous thickness (Position of Lens) y%
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    '************************************************************************* M}|<# i7u  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) @~v|t{G  
    GetCustomElement eID, entity ]RgLTqv4x  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 6KuB<od  
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    ' Delete any shift(s) in z #jAlmxN  
    count = 0 x9V

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    While GetOperationCount(eID)>count RN(>37B
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        GetOperation eID, count, op <WN?  
        If op.Type="ShiftZ" Then gPs%v`y)*D  
            DeleteOperation eID,count +cS%b}O`$  
            count=count-1 LWQ.!;HYp  
        End If S&]AIG)  
        count=count+1 {[~cQgCI  
    Wend l<fZt#T  
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    'Set new shift in Ve,h]/G  
    op.Type = "ShiftZ" >\=~2>FCD  
    op.val1 = taq K?[*9Q'\  
    op.parent = parID
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    AddOperation eID, op $^|I?5xD  
    Print "Set aqueous humor thickness = " & taq-0.55 Id`?yt  
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    '************************************************************************* TX7B(JZD  
    'Radius and conic constant of anterior lens NjT#p8d X  
    '************************************************************************* DA'A-C2  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) o4I&?d7;"  
    GetConic eID, entity, curv, conic z8W@N8IqC  
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    SetConic eID, entity, 1/Rant, CCant (#6E{@eq  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant m/W0vPM1  
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    '************************************************************************* ?'F>DN  
    'Radius and conic constant of posterior lens t[Dg)adc  
    '************************************************************************* -:92<G\D  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) +3B^e%`NPm  
    GetConic eID, entity, curv, conic 0Y7b$~n'Y  
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    SetConic eID, entity, 1/Rpost, CCpost L@> +iZSO  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost HF@K$RPK  
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    '************************************************************************* ?U~}uG^  
    'Lens thickness (Position of posterior lens surface) uMW5F-~-+  
    '************************************************************************* 2w>lnJ-  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) xi5/Wc6  
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    ' Delete any z-shift(s) > "G HLi  
    count = 0 Yv0;UKd  
    While GetOperationCount(eID)>count
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        GetOperation eID, count, op BzFD_A>j;_  
        If op.Type="ShiftZ" Then YDEUiZ~  
            DeleteOperation eID,count 4 I}xygV  
            count=count-1 _ PC}`Y'&  
        End If [5&zyIi  
        count=count+1 y?BzZ16\bL  
    Wend Jz(!eTVs  
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    'Set new z-shift G/tah@N[7  
    op.Type = "ShiftZ" ZSL:q%:.  
    op.val1 = tlens A/kRw'6  
    op.parent = parID d~[^D<5,D  
    AddOperation eID, op v@OyB7}  
    Print "Set lens thickness = " & tlens `_L=~F8  
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    '************************************************************************* {4\hxyw  
    'Lens index of refraction H]:z:AAvX  
    '************************************************************************* '8g/^Y@  
    eID = FindMaterial( "Lens" ) .;gK*`G2W)  
    GetModelMaterial eID, mat 79J@`  
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    mat.Nd = nlens $#V^CmW.  
    SetModelMaterial eID, mat Pw4j?pv2  
    Print "Set lens index of refraction = " & nlens p^_E7k<ag  
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    '************************************************************************* t
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    'Pupil diameter Up|\&2_  
    '************************************************************************* ,}&E=5MF\  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Ln;jB&t  
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    'Adjust pupil diameter (trimming volume inner hole) T7
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 1k@k2rE  
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    ' Adjust pupil location to just in front of the lens Ed/@&52z0  
    parID = FindFullName( "Geometry.Arizona Eye" ) zdA:K25"  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 0`X%&  
    count = 0 Ov{f
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    While GetOperationCount(eID)>count *!De(lhEc  
        GetOperation eID, count, op g%w@v$  
        If op.Type="ShiftZ" Then H~~I6D{8  
            DeleteOperation eID,count "4FL<6  
            count=count-1 EXz5Rue LV  
        End If tK&.0)*=  
        count=count+1 LkFXUt?  
    Wend 6p/gvpZ  
    op.Type = "ShiftZ" JL1%XQ i  
    op.val1 = taq-0.01 {aq\sf;i{  
    op.parent = parID sV7dgvVd  
    AddOperation eID, op OwGl&  
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    Print "Set pupil diameter = " & pupilDiam C]UBu-]#S  
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    'Update AZ Eye subassembly Description Hk-)fl#dr  
    eID = FindFullName( "Geometry.Arizona Eye" ) 3mn0  
    GetEntity eID, entity P[{w23`4  
    entity.Description = "Accommodation = " & A & "D" ^o't&  
    SetEntity eID, entity :>lica_  
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    Update :V2j'R,  
    Print "DONE!" x_Ki5~w5  
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End Sub w <]7:/  
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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： &sL5Pt_  
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Accommodation = 4 Diopters U'LO;s04m  
Pupil Diameter = 4 mm 3m4?l ~  
Set aqueous humor thickness = 2.81 EU,4qO  
Set anterior lens radius = 10.4 and conic constant = -2.375869
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Set posterior lens radius = -4.424557 and conic constant = -3.081019 :o$ R@l  
Set lens thickness = 3.927 H<`[,t  
Set lens index of refraction = 1.42672 _u}v(!PI  
Set pupil diameter = 4 $X5~9s1Wl  
DONE!  L}AR{  
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