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    [转载]FRED运用:Arizona眼睛模型 [复制链接]

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    离线xunjigd
     
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    只看楼主 倒序阅读 楼主  发表于: 2016-02-24
    简介 K`25G_Y3@  
    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。 UUlrfur~  
    lAM"l)Ij  
    模型 f_&bwfbo  
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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。 UqP %S$9  
    #hOAG_a,  
    Table 1. AZ眼睛模型的定义
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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.Z1E:  
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    光源 >q:0w{.TU  
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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。 1i.t^PY  
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    图1. 光源和提示信息使用
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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。 >|Hd*pg))  
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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。 }538vFNi  
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    图2. 字母F光源的设定方法光 o771q}?&`  
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    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 6<h?%j(  
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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。 QT5,_+ho  
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    图4. 视网膜朗伯散射设定
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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。 6QCU:2IiL  
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    图5. 视网膜重点采样规格设定
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    脚本 l%aiG+z%6}  
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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: X0=#e54  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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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。 7>g^OE f  
    余下的脚本计算与屈光度有关的所有参数。 2BU%4IG  
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    分析 (f^K\7HM  
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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。 [jD.l;jF  
    ?mK`Wleh?  
    图7. 字母F在视网膜上颜色分析
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    脚本代码 < c[+60p"  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. ,cR=W|6cQm  
    MCOz-8@|Y  
    Dim entity As T_ENTITY ZiBTe,;  
    Dim op As T_OPERATION Z|YiYQl[)  
    Dim mat As T_MODELMATERIAL >Lh+(M;+F  
    Dim A As Double : QK )Ym  
    Dim pupilDiam As Double v2>.+Eh#  
    Dim eID As Long Z:l.{3J$  
    Dim parID As Long RcUKe,  
    Dim count As Integer e}u# :ysj  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ('/5#^%R  
    Dim tlens As Double, nlens As Double ncEOz1u  
    Dim curv As Double, conic As Double QU/Q5k  
    Dim ok As Long yq{k:)  
    jP{LMmV  
    Sub Main WXqrx*?*+  
    #tyHjk  
        '用户输入对话框 *5DOTWos  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 $7{|  
            TextBox 220,21,40,21,.TextBox1 'default: 0 7l"N%e  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Cd:ofv/3  
            OKButton 40,91,90,21 rrGsam\.  
            CancelButton 190,91,90,21 V9:h4]  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 \;w+_<zE5{  
            TextBox 220,49,40,21,.TextBox2 'default: 4 hadGF%> O6  
        End Dialog CD\k.  
        Dim dlg As UserDialog JzA`*X[  
    rz c}2I  
        ok = Dialog (dlg) [KIK}:  
    4%Q8>mEvT  
        If ok=0 Then    'cancel button was pressed F&r+"O)^-R  
            Print "Execution cancelled." WN?1J4H  
            End |Uz?i7z  
        End If V 0Ul`  
    |];s[^$#  
        'Assign accommodation and pupil diameter & use defaults if field left empty 7xAzd# c?=  
        If dlg.TextBox1 = "" Then )NeI]p  
            A = 0           'Default accommodation ]| oh1q  
        Else JO:40V?op  
            A = CDbl(dlg.TextBox1) OO.. Y  
        End If U88-K1G  
    #t /.fd  
        If dlg.TextBox2 = "" Then 30 Vv Zb  
            pupilDiam = 4   'Default pupil diameter =F2e*?a3  
        Else V#;6 <H"  
            pupilDiam = CDbl(dlg.TextBox2) =/@c9QaV B  
        End If 4&IBNc,sn  
    Cj?X+#J/@d  
        Print " " \>NjeMuWU  
        Print "Accommodation = " & A & " Diopters" |t^7L )&y  
        Print "Pupil Diameter = " & pupilDiam & " mm" " &B/v"nj  
    8fzmCRFH  
        ' Calculate new parameters with accommodation yZ t}Jnv  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 0r=:l/Pz  
    >jjuWO3T  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens k36%n *4  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens S_cba(0-|\  
    T)Byws  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ^|DI9G(Bs  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens tp2CMJc{L  
    {l= !  
        tlens = 3.767 + 0.04*A                  'Lens thickness V.Pb AN  
    M$L1!o1Xf  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction CLI!(8ZW  
    o.DT`L8  
        'Adjust parameters to account for accommodation vKppXm1  
    &) 7umdSgi  
        '************************************************************************* 'ypJGm  
        'Aqueous thickness (Position of Lens) +D|y))fE  
        '************************************************************************* x0wy3+GZc  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) )P\Vd #  
        GetCustomElement eID, entity [nBlHI;&  
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        parID = FindFullName( "Geometry.Arizona Eye" ) Eh;SH^&6  
    2`,{IHu*!  
        ' Delete any shift(s) in z ;wCp j9hir  
        count = 0 /X)fWO S6  
        While GetOperationCount(eID)>count \k;)m-0bj{  
            GetOperation eID, count, op "FI]l<G&  
            If op.Type="ShiftZ" Then %7q,[g8  
                DeleteOperation eID,count R?g qPi-  
                count=count-1 {q%&~  
            End If H)1< ;{:  
            count=count+1 g9OO#C>  
        Wend ;3NA,JA#Y  
    O G#By6O  
        'Set new shift in `-S6g^Y  
        op.Type = "ShiftZ" V}ZF\SG(K  
        op.val1 = taq HErTFY+vC  
        op.parent = parID . Rxz;-VA  
        AddOperation eID, op jJ86Ch  
        Print "Set aqueous humor thickness = " & taq-0.55 (u@p[ncN}  
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        '************************************************************************* S!o!NSn@1  
        'Radius and conic constant of anterior lens :i+Tf~k{  
        '************************************************************************* ,6?L.L  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) hp6S *d  
        GetConic eID, entity, curv, conic gl-O"%rMcL  
    'VCF{0{H~  
        SetConic eID, entity, 1/Rant, CCant T:S+P t~  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant z>+@pj   
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        '************************************************************************* aB~?Y+m  
        'Radius and conic constant of posterior lens ZZp6@@zyq'  
        '************************************************************************* !Y/$I?13Z  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) W>0 36  
        GetConic eID, entity, curv, conic C0;c'4(  
    X2!vC!4P?L  
        SetConic eID, entity, 1/Rpost, CCpost k_.%(ZE  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost n\&[^Q#b|  
    io^^f|  
        '************************************************************************* <m"Zk k  
        'Lens thickness (Position of posterior lens surface) s<LF=qGu  
        '************************************************************************* z 7OTL<h  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) K"-.K]O8E%  
    ^B~z .F i  
        ' Delete any z-shift(s) o7E?A  
        count = 0 u-0-~TwD  
        While GetOperationCount(eID)>count 4M'y9(  
            GetOperation eID, count, op p7}x gUxX  
            If op.Type="ShiftZ" Then ?n9gqwO  
                DeleteOperation eID,count !_)*L+7f_  
                count=count-1 ,Hn{nVU1R=  
            End If Z?Y14L~%  
            count=count+1 x\!Q[  
        Wend <[Ae 0UK  
    vx /NG$  
        'Set new z-shift fEF1&&8^  
        op.Type = "ShiftZ" @#$5_uU8\(  
        op.val1 = tlens \&|)?'8rS  
        op.parent = parID ntE;*F yH  
        AddOperation eID, op 3G|n`dj  
        Print "Set lens thickness = " & tlens s0 hD;`cm  
    > !k  
        '*************************************************************************  chW 1UE  
        'Lens index of refraction E$dPu  
        '************************************************************************* l -us j%\  
        eID = FindMaterial( "Lens" ) =B_vQJF2  
        GetModelMaterial eID, mat `)$'1,]u  
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        mat.Nd = nlens oF[l<OY4  
        SetModelMaterial eID, mat uH S)  
        Print "Set lens index of refraction = " & nlens ] P;Ng=a  
    ^w'y>uFM  
        '************************************************************************* $Kn{x!,"(  
        'Pupil diameter fvg jqiT  
        '************************************************************************* 1TeYA6 t  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) $lmGMljF  
    xG i,\K\:  
        'Adjust pupil diameter (trimming volume inner hole) raRb K8CQ  
    Y S )Q#fP  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" hOjy$Z  
    A46z2  
        ' Adjust pupil location to just in front of the lens d[(KgX9  
        parID = FindFullName( "Geometry.Arizona Eye" ) 9`eu&n@Z  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) &y"e|aE  
        count = 0 R@Ch3l@  
        While GetOperationCount(eID)>count .jW+\mIX  
            GetOperation eID, count, op <hazrKUn  
            If op.Type="ShiftZ" Then W Z`u"t^2V  
                DeleteOperation eID,count ew8f7S[  
                count=count-1 N9 yL(2  
            End If `) s]T.-  
            count=count+1 0w[#`  
        Wend dHjJLs_  
        op.Type = "ShiftZ" Oo<L~7B  
        op.val1 = taq-0.01 #wn`choT'  
        op.parent = parID ea!_/Y  
        AddOperation eID, op w4w[qxV>  
    S{_i1'  
        Print "Set pupil diameter = " & pupilDiam CPGiKE  
    `{BY {  
        'Update AZ Eye subassembly Description #1c%3KaZ I  
        eID = FindFullName( "Geometry.Arizona Eye" ) d 2f   
        GetEntity eID, entity jinDKJ,n;  
        entity.Description = "Accommodation = " & A & "D" ^ 'W<|  
        SetEntity eID, entity Kppi N+||  
    n@IpO i$Q  
        Update _)AX/%^%  
        Print "DONE!" @}sxA9 a  
         ^]_[dqd  
    End Sub znm3b8ns  
    p2Yc:9r9+A  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: =y)e&bj  
    Hg<d%7.  
    Accommodation = 4 Diopters S[g{ )p)  
    Pupil Diameter = 4 mm %dA6vHI,  
    Set aqueous humor thickness = 2.81 Y#[jDS(ip  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 H4l*  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 Fo  K!JX*  
    Set lens thickness = 3.927 ;VVKn=X=S=  
    Set lens index of refraction = 1.42672 A|3'9iL{9  
    Set pupil diameter = 4 $2lrP]`>j.  
    DONE! -DWyKR= j"  
    c8'a<<sj  
    (文章来源:讯技光电)
     
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