切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1173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
    5658
    光币
    22442
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 [&zP$i&  
    Gpgi@ Uf  
    人眼光学模型可用来设计眼科用设备,光学系统注定了要与人眼一起使用。本文演示了这样一个模型:Arizona眼睛模型,在Jim Schwiegerling教授的书中有详细描述:《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源,并包括一个基于想要的屈光度来调整模型的内嵌脚本。 wZOO#&X#r  
    h]D=v B  
    模型 RL&*.r&  
    v =u|D$  
    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。 @lj  
    qrdA?V V  
    Table 1. AZ眼睛模型的定义
    Xz5=fj&  
    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. V*)6!N[5  
    P!vBS "S  
    光源 xw=B4u'z  
    @L~y%#  
    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。 t>25IJG  
    r[?rwc^  
    &bL1G(}  
    图1. 光源和提示信息使用
    C&;'Pw9H  
    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。 )*_YeT&w.  
    JEP"2MN,  
    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。 l'o}4am  
    AOfQqGf  
    图2. 字母F光源的设定方法光 Us%VB q  
    |C(72t?K  
    图3. 字母F在视网膜上位置点列图
    ^|x{E20  
    视网膜的散射 SS`\,%aog  
    JN8k x;@  
    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。 2.NzB7c*CM  
    ct]5\g?U'  
    |FcG$[  
    图4. 视网膜朗伯散射设定
    bh_ALu^CSX  
    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 "Srp/g]a  
    MDB}G '  
    d+IPa<N  
    图5. 视网膜重点采样规格设定
    ck@[% ?  
    脚本 WK=!<FsC$  
    '@W72ML.  
    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: =_UPZ]  
    \{&55>  
    图6. 用户对话框的创建与编辑
    }5]NUxQ_  
    图7. 用户对话框编辑器
    ;N j5NB7  
    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。 /qp`xJ  
    余下的脚本计算与屈光度有关的所有参数。 gVD!.  
    :J<S-d=  
    分析 !BY=HFT  
    {-E{.7  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 T[7DJNdG6  
    3!}#@<j  
    图7. 字母F在视网膜上颜色分析
    % ,X(GwX  
    脚本代码 L3W ^ip4  
    Ft|a/e  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. QK@z##U  
    b"zq3$6*  
    Dim entity As T_ENTITY J L Z  
    Dim op As T_OPERATION .O,gl$y}  
    Dim mat As T_MODELMATERIAL W35nnBU  
    Dim A As Double w"sRK  
    Dim pupilDiam As Double wj?f r?  
    Dim eID As Long i'57|;?  
    Dim parID As Long @-7K~in?^  
    Dim count As Integer ~k J#IA  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double : i(h[0  
    Dim tlens As Double, nlens As Double FIS-xpv$  
    Dim curv As Double, conic As Double 5I<?HsK@  
    Dim ok As Long ogPfz/ hw  
    <h;P<4JX  
    Sub Main Im Tq`  
    ^6`R:SV4Gx  
        '用户输入对话框 56v<!L5%  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 i|=XW6J%  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ZWr\v!4  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 eHjR/MMr_  
            OKButton 40,91,90,21 ? &1?uc  
            CancelButton 190,91,90,21 m2V4nxw]Qp  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 F6 UOo.L)I  
            TextBox 220,49,40,21,.TextBox2 'default: 4 ;j(xrPNb  
        End Dialog S=my;M-  
        Dim dlg As UserDialog zxj!ihs<  
    YnNei 7R  
        ok = Dialog (dlg) 5i#B?+Y  
    g%+nMjif  
        If ok=0 Then    'cancel button was pressed %bv<OMD  
            Print "Execution cancelled." sX=!o})0  
            End # AY+[+  
        End If @!F9}n AP  
    Pjx9@i  
        'Assign accommodation and pupil diameter & use defaults if field left empty GRs;-Jt  
        If dlg.TextBox1 = "" Then d }]b  
            A = 0           'Default accommodation hQk mB|];5  
        Else ZHB'^#b  
            A = CDbl(dlg.TextBox1) %+'&$  
        End If rKjQEO$yi  
    5= F-^  
        If dlg.TextBox2 = "" Then CZ0 {*K:  
            pupilDiam = 4   'Default pupil diameter <fyv^e  
        Else =N3~2=g~A  
            pupilDiam = CDbl(dlg.TextBox2) `&+ L/  
        End If co*5NM^  
    9\"~G)  
        Print " " GnLh qm"\  
        Print "Accommodation = " & A & " Diopters" 7/~"\nN:/  
        Print "Pupil Diameter = " & pupilDiam & " mm" .a^/r'?  
    'DIE#l`  
        ' Calculate new parameters with accommodation L,:U _\HQ  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness *}0Q S@FN  
    hgh1G7A&  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens |, :(3Ml  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens w68qyG|wM  
    ?Jma^ S  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens +6>Pp[%  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens BpK P]V  
    9R E;50h  
        tlens = 3.767 + 0.04*A                  'Lens thickness !YoKKG~_0  
    *]EcjK%  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction  d,H%  
    jrW7AT)\  
        'Adjust parameters to account for accommodation %?cPqRHJ ~  
    bb<Vh2b>R  
        '************************************************************************* F )tNA?p)  
        'Aqueous thickness (Position of Lens) |g9^]bT  
        '************************************************************************* (z.Vwl5  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) .)o5o7H  
        GetCustomElement eID, entity Eod2vr =Q  
    !K@y B)9  
        parID = FindFullName( "Geometry.Arizona Eye" ) X31kHK5F_  
    >B9rr0d0  
        ' Delete any shift(s) in z y}3V3uqK  
        count = 0 EXzY4D ^  
        While GetOperationCount(eID)>count Zdak))7  
            GetOperation eID, count, op {!="PnB  
            If op.Type="ShiftZ" Then  &wj Ob  
                DeleteOperation eID,count \jfW$TtZm  
                count=count-1 6?Wsg`9  
            End If G cbal:q  
            count=count+1 $~2A o[  
        Wend Nn^el' S'  
    i0 R=P[  
        'Set new shift in [R~HhM  
        op.Type = "ShiftZ" jVA xa|S  
        op.val1 = taq j@:L MR>  
        op.parent = parID b_LzG_n!   
        AddOperation eID, op \K4m~e@!  
        Print "Set aqueous humor thickness = " & taq-0.55 ql zL<  
    !F%dE!  
        '************************************************************************* G%P]qi  
        'Radius and conic constant of anterior lens CUtk4;^y#  
        '************************************************************************* HgMDw/D(  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 4Pt0^;H&jn  
        GetConic eID, entity, curv, conic bv] ZUF0  
    cEN^H  
        SetConic eID, entity, 1/Rant, CCant q}8R>`Z{  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant U-Iwda8v  
    57#:GN$EL  
        '************************************************************************* \ pq]q  
        'Radius and conic constant of posterior lens }skXh_Vu4  
        '************************************************************************* WT0U)x( m5  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Z<wg`  
        GetConic eID, entity, curv, conic 'J\%JAR@  
    |?0C9  
        SetConic eID, entity, 1/Rpost, CCpost 4ASc`w*0  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost _7;#0B  
    6tJM*{$$H  
        '************************************************************************* ~vt8|OOo0  
        'Lens thickness (Position of posterior lens surface) rN*4Y  
        '************************************************************************* Z2ZS5a  
    `zvYuKQ.}  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 4v{gc/g  
    "kL5HD]TC  
        ' Delete any z-shift(s) yK{~  
        count = 0 ._nhW*  
        While GetOperationCount(eID)>count 1\3n   
            GetOperation eID, count, op QM$?}>:  
            If op.Type="ShiftZ" Then .z9JoQ  
                DeleteOperation eID,count  g6~uf4;  
                count=count-1 :8rqTBa`  
            End If  R` N-^x  
            count=count+1 s5[ Cr"q7B  
        Wend } o=g)  
    Kg%_e9nj#  
        'Set new z-shift ,,6e }o6  
        op.Type = "ShiftZ" )cvC9gt  
        op.val1 = tlens VMNihx0FJ  
        op.parent = parID 7N:,F9V<  
        AddOperation eID, op Z)ObFJMG5  
        Print "Set lens thickness = " & tlens wvgX5P>  
    ptsi\ 7BG  
        '************************************************************************* LsLsSV  
        'Lens index of refraction P!-9cd1 C,  
        '************************************************************************* HID;~Ne  
        eID = FindMaterial( "Lens" ) -dza_{&+iZ  
        GetModelMaterial eID, mat }6o` in>M  
    X2EC+<  
        mat.Nd = nlens {? 6]_J  
        SetModelMaterial eID, mat ~< k'{  
        Print "Set lens index of refraction = " & nlens zIlQqyOQ8  
    tewC *%3V  
        '************************************************************************* 6.k2,C4dT<  
        'Pupil diameter /|>z7#?m^  
        '************************************************************************* 1|Fukx<@J<  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 1c\$ziB  
    }3QEclZr  
        'Adjust pupil diameter (trimming volume inner hole) 0uj3kr?cv  
    C^ uXJ~8  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" K)&AR*Tc  
    ;ASlsUE\)  
        ' Adjust pupil location to just in front of the lens `"    
        parID = FindFullName( "Geometry.Arizona Eye" ) = i `o+H  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) uv Z!3UH.  
        count = 0 j{nL33T%  
        While GetOperationCount(eID)>count }PoB`H'K5  
            GetOperation eID, count, op -`A6K!W&~p  
            If op.Type="ShiftZ" Then Of-l<Ks\  
                DeleteOperation eID,count &'i>5Y  
                count=count-1 1YQ|KJ*K  
            End If @C?RbTHy  
            count=count+1 x|1OGbBK  
        Wend MvQ0"-ZQ  
        op.Type = "ShiftZ" g_-Y- .M  
        op.val1 = taq-0.01 IY+P Yad  
        op.parent = parID qL] !/}  
        AddOperation eID, op A5z5e# ,u  
    0<fN<iR`  
        Print "Set pupil diameter = " & pupilDiam C?X^h{T p  
    Kc0KCBd8];  
        'Update AZ Eye subassembly Description +1_NB;,e  
        eID = FindFullName( "Geometry.Arizona Eye" ) <&Y7Q[  
        GetEntity eID, entity eR =P  
        entity.Description = "Accommodation = " & A & "D" iz& )FuOr  
        SetEntity eID, entity V) C4 sG  
    YGNO]Q~A  
        Update K oo%mr   
        Print "DONE!" L`tr7EEr  
         :<!a.%=  
    End Sub IrM Ws86;  
    +%oXPG?  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: 6gNsh  
    P @G2F:}  
    Accommodation = 4 Diopters 5hg:@i',  
    Pupil Diameter = 4 mm 8-+Ce;h  
    Set aqueous humor thickness = 2.81 0M>+.}e+  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 x}{/) ?vC  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 ~4<xTP\*  
    Set lens thickness = 3.927 P|l62!m<   
    Set lens index of refraction = 1.42672 1=}+NK!  
    Set pupil diameter = 4 Mnc9l ^  
    DONE! 4v_<<l  
    wa5wkuS)ld  
    pxDkf|*   
    QQ:2987619807 >;LXy  
     
    分享到