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    [分享]Arizona眼睛模型 [复制链接]

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    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 4#U}bN  
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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。 K %^n.  
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    模型 ~j0rORy]  
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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。 IThd\#=  
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    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. n ]ikc|  
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    光源 V+d_1] l  
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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。 >r.]a`  
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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。 MB plhVK8  
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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。 O5\r%&$xd  
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    图2. 字母F光源的设定方法光 Io6/Fv>!  
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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 $ /VQsb  
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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。 Ebg8qDE  
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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。 A~ya{^}  
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    图5. 视网膜重点采样规格设定
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    脚本 jW/WG tz  
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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: +`y(S}Z  
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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。 .6?"<zdPU  
    余下的脚本计算与屈光度有关的所有参数。 5=>1>HYM  
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    分析 lH-VqkR\  
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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。 !oLn=  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 &|>@K#V8-;  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. /qpSmRL  
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    Dim entity As T_ENTITY <O#&D|EMd|  
    Dim op As T_OPERATION 1#vy# '  
    Dim mat As T_MODELMATERIAL V^~RDOSy7n  
    Dim A As Double q? ,PFvs"  
    Dim pupilDiam As Double ;\MWxh,K  
    Dim eID As Long /Vlc8G  
    Dim parID As Long 1ni+)p>]  
    Dim count As Integer K;K0D@>]HR  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ]4:QqdV  
    Dim tlens As Double, nlens As Double 'u,|*o  
    Dim curv As Double, conic As Double D:P(;  
    Dim ok As Long |k a _Zy  
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    Sub Main x6ghO-s  
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        '用户输入对话框 ZR>BK,  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Q3@zUjq_Q  
            TextBox 220,21,40,21,.TextBox1 'default: 0 w OL,LU  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 D%SOX N  
            OKButton 40,91,90,21 7Sdo*z  
            CancelButton 190,91,90,21 Z)!8a$M~  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 :X>Wd+lY:_  
            TextBox 220,49,40,21,.TextBox2 'default: 4 [6GYYu\  
        End Dialog ly0R'4j \  
        Dim dlg As UserDialog oEIpv;:_  
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        ok = Dialog (dlg) fQ+whGB  
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        If ok=0 Then    'cancel button was pressed qs4jUm  
            Print "Execution cancelled." g 9,"u_  
            End 1 ?@HOu  
        End If \w9}O2lL  
    ]#0 (  
        'Assign accommodation and pupil diameter & use defaults if field left empty WjD885Xo  
        If dlg.TextBox1 = "" Then ;zCUx*{  
            A = 0           'Default accommodation RpdUR*K9x  
        Else `}X3f#eO&  
            A = CDbl(dlg.TextBox1) |)x7qy`  
        End If qxZIH  
    "*vrrY  
        If dlg.TextBox2 = "" Then @yp0WB  
            pupilDiam = 4   'Default pupil diameter QM,#:m1o  
        Else ==Gc%  
            pupilDiam = CDbl(dlg.TextBox2) ~^wSwd[  
        End If _^ hg7&dF  
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        Print " " =Rd`"]Mnfb  
        Print "Accommodation = " & A & " Diopters" 2|pTw5z~  
        Print "Pupil Diameter = " & pupilDiam & " mm" 0`/G(ukO  
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        ' Calculate new parameters with accommodation :a wt7lqv  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness d$IROZK-D  
    %;`Kd}CO  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens ljFq;!I5  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens %=**cvVy  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Q)75?mn  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens i>M%)HN  
    =\Q< TY  
        tlens = 3.767 + 0.04*A                  'Lens thickness *_D/_Rp7  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction uq5?t  
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        'Adjust parameters to account for accommodation _CD~5EA:  
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        '************************************************************************* ZP"; B^J  
        'Aqueous thickness (Position of Lens) [@@{z9c  
        '************************************************************************* WNR]GI  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) $6Ma{rC|  
        GetCustomElement eID, entity G'|ql5Zw  
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        parID = FindFullName( "Geometry.Arizona Eye" ) {-A|f  
    {4_s:+v0  
        ' Delete any shift(s) in z ^ `LqNG  
        count = 0 &'6/H/J  
        While GetOperationCount(eID)>count ?Q:SVxzUd  
            GetOperation eID, count, op }s,NM%oI  
            If op.Type="ShiftZ" Then l";Yw]:^  
                DeleteOperation eID,count ]B>76?2W  
                count=count-1 #j2kT  
            End If ?G`m;S  
            count=count+1 ]_ C"A  
        Wend RV~t%Sw^  
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        'Set new shift in Ysm RY=3  
        op.Type = "ShiftZ" @=kg K[t 9  
        op.val1 = taq v3"6'.f;bY  
        op.parent = parID i l^;2`]&  
        AddOperation eID, op 8AR8u!;8  
        Print "Set aqueous humor thickness = " & taq-0.55 [,Ehu<mEK  
    { ^o.f  
        '************************************************************************* ]>M\|,wh  
        'Radius and conic constant of anterior lens |WB-Ng  
        '************************************************************************* &S4*x|-C&  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) T"xJY#)}  
        GetConic eID, entity, curv, conic |z)s9B;:#i  
    |d0ZB_ci  
        SetConic eID, entity, 1/Rant, CCant [!uzXVS3  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant {aAd (~YZ  
    ]:e_Y,@  
        '************************************************************************* >XtfT'  
        'Radius and conic constant of posterior lens q,Gymh;  
        '************************************************************************* B[8bkFS>]  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) >/ay'EyY;>  
        GetConic eID, entity, curv, conic *RkUF!)(  
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        SetConic eID, entity, 1/Rpost, CCpost ^E^`"  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost _}R9!R0O  
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        '************************************************************************* 3\W/VBJJ  
        'Lens thickness (Position of posterior lens surface) [9 MH"\  
        '************************************************************************* 5W)ST&YPL*  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) aL1%BGlmZ<  
    evZcoH3~  
        ' Delete any z-shift(s) 40?RiwwD  
        count = 0 L-+g`  
        While GetOperationCount(eID)>count +/[M Ex=   
            GetOperation eID, count, op +q&Hj|;8r  
            If op.Type="ShiftZ" Then I|rb"bG  
                DeleteOperation eID,count i"&FW&W  
                count=count-1 |Gic79b  
            End If yzN[%/  
            count=count+1 f<8Hvumw  
        Wend vM/*S 6[  
    ko9}?qs  
        'Set new z-shift ;VE y{%nF  
        op.Type = "ShiftZ" ]k!Xb  
        op.val1 = tlens ^+x?@$rq  
        op.parent = parID #gbB// <  
        AddOperation eID, op Db"mq'vT  
        Print "Set lens thickness = " & tlens F*P0=DD  
    EHUx~Q   
        '************************************************************************* O cL7] b0  
        'Lens index of refraction uzdPA'u  
        '************************************************************************* 6+$2rS$1V  
        eID = FindMaterial( "Lens" ) %>FtA)  
        GetModelMaterial eID, mat CM?:\$ 4  
    , ;,B7g  
        mat.Nd = nlens f3O6&1D  
        SetModelMaterial eID, mat v@$N,g  
        Print "Set lens index of refraction = " & nlens `<9>X9.+  
    C6)Y ZC  
        '************************************************************************* uG\~Hxqw7O  
        'Pupil diameter D|q~n)TW5  
        '************************************************************************* dJR[9T_OF  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) "0HUaU,e  
    $e+sqgU  
        'Adjust pupil diameter (trimming volume inner hole) HAn{^8"@  
    Vg'R=+Wb  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" LwB1~fF  
    iTHwH{!  
        ' Adjust pupil location to just in front of the lens ~A>fB2.pM  
        parID = FindFullName( "Geometry.Arizona Eye" ) necY/&Ld-  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) `/sNX<mp  
        count = 0 j !*,(  
        While GetOperationCount(eID)>count E`TZ:W]r,  
            GetOperation eID, count, op * BM|luYL  
            If op.Type="ShiftZ" Then e)uC  
                DeleteOperation eID,count s!(R  
                count=count-1  w*`:v$  
            End If kk78*s {6  
            count=count+1 ^xHKoOTj[  
        Wend ZxvH1qx8  
        op.Type = "ShiftZ" l\Ozy  
        op.val1 = taq-0.01 ( eKgc  
        op.parent = parID JX0M3|I=  
        AddOperation eID, op :UdW4N-  
    W'4/cO  
        Print "Set pupil diameter = " & pupilDiam %"`p&aE:  
    8Qg{@#Wr  
        'Update AZ Eye subassembly Description ]r;rAOWVV  
        eID = FindFullName( "Geometry.Arizona Eye" ) B_d\eD  
        GetEntity eID, entity =7V4{|ESfy  
        entity.Description = "Accommodation = " & A & "D" kgo#JY-4  
        SetEntity eID, entity CE3l_[c  
    8C{&i5kj\E  
        Update m%L!eR  
        Print "DONE!" &m3-][ !n  
         \=0;EI-j  
    End Sub Wx0i_HFR  
    b d 1^  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: Nk9=A4=|  
    ;7\Fx8"s[  
    Accommodation = 4 Diopters H?"M&mF  
    Pupil Diameter = 4 mm ]+:yfDtZd  
    Set aqueous humor thickness = 2.81 EA~xxKq  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 [ K?  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 %gmx47  
    Set lens thickness = 3.927 d&^b=d FDu  
    Set lens index of refraction = 1.42672 [r`KoHwdm  
    Set pupil diameter = 4 1]If< <  
    DONE! /<-PW9X?  
     ]~;*9`:  
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    QQ:2987619807 ,g?ny<#o  
     
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