切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1762阅读
    • 0回复

    [分享]Arizona眼睛模型 [复制链接]

    上一主题 下一主题
    离线infotek
     
    发帖
    6621
    光币
    27254
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 VMF?qT3Nd  
     6p@[U>`  
    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。 #|8%h  
    '4 d4i  
    模型 ;o)'dK  
    > dVhIbG  
    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。 .Y2Hd$rs  
    QxPPgn7'  
    Table 1. AZ眼睛模型的定义
    Ohgu*5!o  
    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. cQxUEY('+  
    66-\}8f8a  
    光源 94O\M RQ*  
    Wm"q8-<<  
    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。 vN v'%;L  
    FO(QsR=\s  
    0827z  
    图1. 光源和提示信息使用
    %CYo, e  
    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。 Y=|20Y\K  
    F,)+9/S&  
    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。 G6{'|CV  
    ^w%%$9=:r  
    图2. 字母F光源的设定方法光 ,_H H8[&  
    HCrQ+r{g  
    图3. 字母F在视网膜上位置点列图
    4".I*ij  
    视网膜的散射 &?Erkc~#  
    i,"Xw[H*s  
    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。 9W(&g)`  
    ]v5/K  
    "oiN8#Hf  
    图4. 视网膜朗伯散射设定
    R}w}G6"\  
    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。 Fab]'#1q4  
    ^ )"Il  
    4D n&+=fq  
    图5. 视网膜重点采样规格设定
    @1xVWSF  
    脚本 XXX y*/P  
    l]D $QT3  
    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: NAtDt=  
    N LQ".mM+  
    图6. 用户对话框的创建与编辑
    _:NQF7X#ug  
    图7. 用户对话框编辑器
    #wT6IU1  
    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 f*"T]AX0  
    余下的脚本计算与屈光度有关的所有参数。 :qqG%RB  
    k7@QFw4 j  
    分析 0+1!-Wo  
    zJ(DO>,p&  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 At<MY`ka  
    G"m0[|XH  
    图7. 字母F在视网膜上颜色分析
    cy(w*5Upu  
    脚本代码 4Zu1G#(zP  
    _kRc"MaB  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. wXp:XZ:]T  
    Kv!:2br  
    Dim entity As T_ENTITY 6 %aaK|0  
    Dim op As T_OPERATION 3f^jy(  
    Dim mat As T_MODELMATERIAL U5-8It2OR  
    Dim A As Double |.RyF@N`T  
    Dim pupilDiam As Double ng|^Zm%   
    Dim eID As Long {E(2.'d  
    Dim parID As Long ed5oN^V.<  
    Dim count As Integer oDD"h,Z  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Kv1~,j6  
    Dim tlens As Double, nlens As Double k ?6d\Q  
    Dim curv As Double, conic As Double Hc<@T_h+2  
    Dim ok As Long IQC[ewk  
    ^{IZpT3  
    Sub Main 6~ y'  
    \WnTpl>B  
        '用户输入对话框 S]%,g%6i  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 r{d@74  
            TextBox 220,21,40,21,.TextBox1 'default: 0 R#ZJLT  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 xc @$z* w  
            OKButton 40,91,90,21 3)CIqN  
            CancelButton 190,91,90,21 RAhDSDf  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 2.Ww(`swL  
            TextBox 220,49,40,21,.TextBox2 'default: 4 Z@x&  
        End Dialog #l&*&R~>  
        Dim dlg As UserDialog iNl<<0a  
    (i(E~^O  
        ok = Dialog (dlg) 9?hF<}1XH}  
    ; xw9#.d#D  
        If ok=0 Then    'cancel button was pressed _hl| 3 eW5  
            Print "Execution cancelled." D}}?{pe  
            End Z-ci[Zv  
        End If bG"FN/vg  
    kk<%VKC  
        'Assign accommodation and pupil diameter & use defaults if field left empty :epB:r  
        If dlg.TextBox1 = "" Then saZK+kD4I  
            A = 0           'Default accommodation mYJ8O$  
        Else iNi1+sm  
            A = CDbl(dlg.TextBox1) sl$y&C-  
        End If BB3 a8  
    ,MJddbcg  
        If dlg.TextBox2 = "" Then C^'r>0  
            pupilDiam = 4   'Default pupil diameter c 8  
        Else Z>3~n  
            pupilDiam = CDbl(dlg.TextBox2) 0Qeda@J  
        End If euT=]j  
    p(I^Y{sGI  
        Print " " yyu-y0_  
        Print "Accommodation = " & A & " Diopters" 91&=UUkK?  
        Print "Pupil Diameter = " & pupilDiam & " mm" hTZ6@i/pS  
    +&f_k@+  
        ' Calculate new parameters with accommodation N GnE  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness $,r%@'=&  
    S{2;PaK  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens NW0se DL  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ?Q=(?yR0]  
    a(O@E%|u  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens U,yZ.1V^:  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 6 mLC{X[  
    mP15PZ  
        tlens = 3.767 + 0.04*A                  'Lens thickness D1>*ml  
    &u[F)|  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction [-Y~g%M  
    ~MB)}!S:  
        'Adjust parameters to account for accommodation F:<+}{Av  
    rs>,p)  
        '************************************************************************* ] X]!xvN@  
        'Aqueous thickness (Position of Lens) /i@.Xg@:  
        '************************************************************************* r/NaoIrJV  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) s/~[/2[bnf  
        GetCustomElement eID, entity <T.R%Jys  
    Q2)5A& U\  
        parID = FindFullName( "Geometry.Arizona Eye" ) m^ar:mK@  
    +J|LfXgB  
        ' Delete any shift(s) in z KdHkX+-R  
        count = 0 hTby:$aCg  
        While GetOperationCount(eID)>count UBQtD|m\  
            GetOperation eID, count, op .':17 $c`H  
            If op.Type="ShiftZ" Then u}R|q  
                DeleteOperation eID,count UDJ#P9uy  
                count=count-1 dE[X6$H[  
            End If G&wYV[Ln  
            count=count+1 +YCWoX 2  
        Wend V5h_uGOD  
    T=V{3v@zs  
        'Set new shift in g_tEUaiK  
        op.Type = "ShiftZ" 5$Kv%U  
        op.val1 = taq Gk58VODo  
        op.parent = parID ^Vh^Z)gGi  
        AddOperation eID, op ^5 "yY2}-  
        Print "Set aqueous humor thickness = " & taq-0.55 l&] %APL  
    SU7,uxF  
        '************************************************************************* HH(2  
        'Radius and conic constant of anterior lens u5U^}<}y}  
        '************************************************************************* 9 s2z=^  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ,e`n2)  
        GetConic eID, entity, curv, conic !VG ]~lc  
    g;o5m}  
        SetConic eID, entity, 1/Rant, CCant n~w[ajC/  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 4T)`%Oo<}  
    ~$ ?85   
        '************************************************************************* T|YMU?4  
        'Radius and conic constant of posterior lens V*%><r  
        '************************************************************************* B=_5gZ4Y  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ?5pZp~  
        GetConic eID, entity, curv, conic |N^8zo :  
    Uul5h8F  
        SetConic eID, entity, 1/Rpost, CCpost 9dp4&&Z+F  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost a)+*Gf7?  
    65+2+p  
        '************************************************************************* Jl6biJx  
        'Lens thickness (Position of posterior lens surface) VeFfkg4  
        '************************************************************************* 6(A"5B=\  
    =7~;*Ts  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 11A;z[Zk  
    [zrFW g6N  
        ' Delete any z-shift(s) TPN1Rnt0`  
        count = 0 X1u\si%.4S  
        While GetOperationCount(eID)>count #iD`Bg!VXc  
            GetOperation eID, count, op 90<a'<\|  
            If op.Type="ShiftZ" Then KAr5>^<zw  
                DeleteOperation eID,count 2'ws@U}lR  
                count=count-1 a(`"qS  
            End If gd]k3XN$f  
            count=count+1 #xq|/JWs  
        Wend A4L.bBl  
    \/ Zo*/  
        'Set new z-shift -3y $j+  
        op.Type = "ShiftZ" _*t75e$-  
        op.val1 = tlens 8)f/H&)>8  
        op.parent = parID 3?&P^{  
        AddOperation eID, op ,;h}<("q  
        Print "Set lens thickness = " & tlens h)r=+Q\'(S  
    V )oKsO  
        '************************************************************************* leXdxpc  
        'Lens index of refraction Q'^$;X~-<  
        '************************************************************************* Fcn@j#[J  
        eID = FindMaterial( "Lens" ) B|AIl+y  
        GetModelMaterial eID, mat /5f=a  
    @[ '?AsO  
        mat.Nd = nlens E,A9+OKxJ  
        SetModelMaterial eID, mat "t>H B6^  
        Print "Set lens index of refraction = " & nlens fhki!# E8M  
    /EVXkf0  
        '************************************************************************* $cO-+Mr-~  
        'Pupil diameter ch/DBu  
        '************************************************************************* %L  nG^L  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) kh"APxQ79  
    AD'c#CT  
        'Adjust pupil diameter (trimming volume inner hole) Qer}eg`R  
    8/|1FI  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" X&%;(`  
    ~y:?w(GD  
        ' Adjust pupil location to just in front of the lens 5%fR9?)  
        parID = FindFullName( "Geometry.Arizona Eye" ) )},/=#C0  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) e= ",58  
        count = 0 '81WogH:  
        While GetOperationCount(eID)>count 3pkx3tp{  
            GetOperation eID, count, op mGUG  
            If op.Type="ShiftZ" Then %cq8%RT  
                DeleteOperation eID,count 1z8fhE iiE  
                count=count-1 `S]DHxS  
            End If S^SF!k=  
            count=count+1 Ec!R3+  
        Wend _&$nJu  
        op.Type = "ShiftZ" B,{Q[  
        op.val1 = taq-0.01 Ehtb`Ms  
        op.parent = parID )dRB I)P  
        AddOperation eID, op 6"o@d8>v  
    6[]O3Aa  
        Print "Set pupil diameter = " & pupilDiam v<]$,V]  
    h]^= y.Q  
        'Update AZ Eye subassembly Description q{Gf@  
        eID = FindFullName( "Geometry.Arizona Eye" ) ue!wo-|#G  
        GetEntity eID, entity $4>x4*  
        entity.Description = "Accommodation = " & A & "D" %T~LK=m  
        SetEntity eID, entity $&0\BvS  
    .!g  
        Update }vX/55  
        Print "DONE!" #Gu(h(Z s  
         k{+ Gv}Y  
    End Sub lUM-~  
    (=QiXX1r  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: 24d{ol)  
    (!diPwcv  
    Accommodation = 4 Diopters od]1:8OF  
    Pupil Diameter = 4 mm W&9X <c*  
    Set aqueous humor thickness = 2.81 FmtV[C #  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 'X1/tB8*  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 BGL-lJrG  
    Set lens thickness = 3.927 #}nDX4jI  
    Set lens index of refraction = 1.42672 Wg=4`&F^  
    Set pupil diameter = 4 #j6qq3OG  
    DONE! G\H|\i  
    Jnq}SUev  
    Ku]<$uo  
    QQ:2987619807 kBJx`tjtp  
     
    分享到