切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 2206阅读
    • 0回复

    [技术]Arizona眼睛模型 [复制链接]

    上一主题 下一主题
    离线infotek
     
    发帖
    6613
    光币
    27214
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2021-10-22
    简介 ,I(PDlvtM  
    MhE'_sq  
    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。 2r3]DrpJ  
    ;n-)4b]\  
    模型 {nyQ]Nu"  
    R @h@@lSf  
    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。 x~7_`=}rO  
    UfE41el:  
    Table 1. AZ眼睛模型的定义
    >a5M:s)  
    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. (thDv rT@2  
    "8p fLI  
    光源 *O`76+iZ|_  
    1|_8+)i;  
    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。 h q5=>p  
    LU#DkuIG  
    gk%8iT  
    图1. 光源和提示信息使用
     Bld%d:i  
    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。 ;$ot,mH?T  
    $VX<UK$|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。 }]-SAM  
    ya+eGD@N':  
    图2. 字母F光源的设定方法光 %-zAV*>  
    owYSR?aG  
    图3. 字母F在视网膜上位置点列图
    E8-8E2i,  
    视网膜的散射 B{ i5UhxD  
    -:O~J#D  
    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。 C:$12{I?*  
    \O]1QM94Y  
    7l-` k  
    图4. 视网膜朗伯散射设定
    n&?]GyQ  
    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 4o:  
    o=!3=2@dh  
    fk(l.A$  
    图5. 视网膜重点采样规格设定
    S#M<d~rK  
    脚本 *^'$YVd#  
    *fBI),bZa  
    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: dHU#Y,v  
    3I)!.N[m  
    图6. 用户对话框的创建与编辑
    X@,xwsM%tb  
    图7. 用户对话框编辑器
    (t.pM P4  
    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。 #y~`nyg%|  
    余下的脚本计算与屈光度有关的所有参数。 "s']@Qv  
    _8Si8+j  
    分析 D`r^2(WW  
    !_+LmBd G  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 #S[:Q.0 ;  
     E%g_O_  
    图7. 字母F在视网膜上颜色分析
    NT~L=x sY  
    脚本代码 F,^<  
    9R XT  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. 5S PGv}if  
    {7`eR2#Wq  
    Dim entity As T_ENTITY &A=q_  
    Dim op As T_OPERATION Jo1=C.V`Y  
    Dim mat As T_MODELMATERIAL `pp"htm   
    Dim A As Double M ) 9Ss  
    Dim pupilDiam As Double T-=sC=sS,  
    Dim eID As Long !<"H73?fl  
    Dim parID As Long ArBgg[i  
    Dim count As Integer YoD1\a|  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double  D7%`hU  
    Dim tlens As Double, nlens As Double W,zlR5+Jk  
    Dim curv As Double, conic As Double saOXbt(&  
    Dim ok As Long *iB_$7n`  
    XUU l*5^  
    Sub Main I;`)1   
    MVV9[f  
        '用户输入对话框 #vhxW=L`=  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 mA5xke_)  
            TextBox 220,21,40,21,.TextBox1 'default: 0 qyMR0ai-  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 |H&2[B"l  
            OKButton 40,91,90,21 _20nOg`o  
            CancelButton 190,91,90,21 |F36^  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 "Vp+e%cqG  
            TextBox 220,49,40,21,.TextBox2 'default: 4 TY"=8}X1  
        End Dialog sygAEL;.  
        Dim dlg As UserDialog \AOVdnM:  
    Qcu1&t\C  
        ok = Dialog (dlg) d$<HMs:o@  
    >JVZ@ PV H  
        If ok=0 Then    'cancel button was pressed s OD>mc#%Y  
            Print "Execution cancelled." VsOn j~@  
            End :)+|q  
        End If e:IUO1#  
    fZ6lnZ  
        'Assign accommodation and pupil diameter & use defaults if field left empty $b;9oST  
        If dlg.TextBox1 = "" Then [3++Q-rR=  
            A = 0           'Default accommodation #SQao;>  
        Else n~ \"W  
            A = CDbl(dlg.TextBox1) Y5fwmH,a-  
        End If E1:{5F5/  
    5nIm7vlQm  
        If dlg.TextBox2 = "" Then HK>!%t0S  
            pupilDiam = 4   'Default pupil diameter 79<{cexP  
        Else DPn]de:e  
            pupilDiam = CDbl(dlg.TextBox2) IbQ3*  
        End If )sG`sET]`f  
    hKb-l`KO  
        Print " " l>)0OP]  
        Print "Accommodation = " & A & " Diopters" [ aj F  
        Print "Pupil Diameter = " & pupilDiam & " mm" G"0YCi#I|  
    KumbG>O  
        ' Calculate new parameters with accommodation uW!',"0ER  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness D`3m%O(?  
    Ia:n<sZU  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens ]O s!=rt  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens V%?oI]" l  
    fkWuSGi  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens HF}%Ow  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens /02|b}{  
    g@YJ#S(}  
        tlens = 3.767 + 0.04*A                  'Lens thickness s=Pwkte  
    xlF$PpRNM  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction j}Lt"r2F  
    p=jD "lq  
        'Adjust parameters to account for accommodation N ~L3 9  
    2MmqGB}YcW  
        '************************************************************************* FQ>KbZh  
        'Aqueous thickness (Position of Lens) )s1W)J?8  
        '************************************************************************* V*SKWP  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) W!4(EdT*Cq  
        GetCustomElement eID, entity <*0^X%Vf\  
    }|MGYS)  
        parID = FindFullName( "Geometry.Arizona Eye" ) Epsc2TuH7  
    ac6Lv}w_  
        ' Delete any shift(s) in z B<(v\=xZ  
        count = 0 Az[Yvu'<  
        While GetOperationCount(eID)>count vK)^;T ;  
            GetOperation eID, count, op .]g>.  
            If op.Type="ShiftZ" Then U)a}XRS  
                DeleteOperation eID,count F`-|@k  
                count=count-1 vttmSdY  
            End If F,EcqM'f  
            count=count+1 +CtsD9PA  
        Wend " jly[M}C  
    ENm\1  
        'Set new shift in \Fj$^I>C  
        op.Type = "ShiftZ" vs;T}' O  
        op.val1 = taq K?:rrd=7q  
        op.parent = parID ~|kre:j9  
        AddOperation eID, op %k @"*  
        Print "Set aqueous humor thickness = " & taq-0.55 c*$&MCh  
    2,?4'0Z@R  
        '************************************************************************* v+A$CGH96  
        'Radius and conic constant of anterior lens hX(:xc  
        '************************************************************************* CsG1HR@  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) V6Ie\+@.\  
        GetConic eID, entity, curv, conic :a#Mq9ph!  
    W*i PseXq  
        SetConic eID, entity, 1/Rant, CCant yg\bCvL&  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 9{\e E]0  
    #FKo:id`K  
        '************************************************************************* #n5q$  
        'Radius and conic constant of posterior lens I `:nb  
        '************************************************************************* TcA+ov>TD  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 0G?0 Bo  
        GetConic eID, entity, curv, conic 26un=  
    +"rZ<i  
        SetConic eID, entity, 1/Rpost, CCpost UO$z_ p]w  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost p>7 !"RF:U  
    JnE\E(ez  
        '************************************************************************* ;|&Ak_I2G  
        'Lens thickness (Position of posterior lens surface) '|Dm\cy  
        '************************************************************************* JTB_-J-TU  
    4HEp}Y"}V  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ?XO$ 9J  
    =FUORj\O  
        ' Delete any z-shift(s) =o]V!MW  
        count = 0 {` Bgxejf  
        While GetOperationCount(eID)>count Z'p7I}-qr  
            GetOperation eID, count, op 7c$;-O  
            If op.Type="ShiftZ" Then JVE]Qb_  
                DeleteOperation eID,count 7@al)G;~  
                count=count-1 9Y&,dBj+  
            End If i~:FlW]  
            count=count+1 g &~T X  
        Wend i3g;B?54  
    kuq3QW<  
        'Set new z-shift f@lRa>Z(Fm  
        op.Type = "ShiftZ" |9. `qv  
        op.val1 = tlens .6S]\dp7~  
        op.parent = parID m@  b~  
        AddOperation eID, op 6N[XWyS  
        Print "Set lens thickness = " & tlens P [-2^1P"  
    rf1Us2vp  
        '************************************************************************* ];bB7+  
        'Lens index of refraction gn"_()8cT  
        '************************************************************************* o mstJ9  
        eID = FindMaterial( "Lens" ) 99 /fI  
        GetModelMaterial eID, mat  so_  
    x"0*U9f  
        mat.Nd = nlens Cc^`M9dP  
        SetModelMaterial eID, mat v&oE!s#  
        Print "Set lens index of refraction = " & nlens C(7uvQ  
    |u,2A1  
        '************************************************************************* NFTEp0eP  
        'Pupil diameter ^pA|ubZ  
        '************************************************************************* -~T?xs0_  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) OV ~|@{6T  
    xq1 =O  
        'Adjust pupil diameter (trimming volume inner hole) &A>Hq/Y  
    u (V4KUk  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" RbUBKMZ U  
    (@Q@B%!!K  
        ' Adjust pupil location to just in front of the lens #UGm/4C  
        parID = FindFullName( "Geometry.Arizona Eye" ) Q- 78B'!=  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) =\H.C@r  
        count = 0 ,W"Q)cL  
        While GetOperationCount(eID)>count X?5M)MP+I  
            GetOperation eID, count, op %IGcn48J  
            If op.Type="ShiftZ" Then @4dB$QF`&  
                DeleteOperation eID,count _ h\wH;  
                count=count-1 * Zb-YA  
            End If KrN#>do&<  
            count=count+1 H: q(T >/w  
        Wend l?E7'OEF:  
        op.Type = "ShiftZ" Qe<D X"  
        op.val1 = taq-0.01 FaO=<jYi  
        op.parent = parID Fa78yY+6  
        AddOperation eID, op 16=tHo8|  
    f6n'g:&.W  
        Print "Set pupil diameter = " & pupilDiam @WVpDhG  
    A\J|eSG'$  
        'Update AZ Eye subassembly Description qD:3;85  
        eID = FindFullName( "Geometry.Arizona Eye" ) )HWf`;VQ  
        GetEntity eID, entity "1P8[  
        entity.Description = "Accommodation = " & A & "D" bm9@A]yP  
        SetEntity eID, entity < wV?B9j  
    X=]FVHV;  
        Update n |5+HE4@  
        Print "DONE!" `[x`#irD  
         f%ude@E3  
    End Sub 8+m;zvDSU  
    <}x_F)E[t  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: GQ~wx1jj1  
    a& b75.-  
    Accommodation = 4 Diopters I_xvg >i  
    Pupil Diameter = 4 mm .T0w2Dv/  
    Set aqueous humor thickness = 2.81 N3 qtq9{  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 *k$&U3=  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 xu[6h?u(h8  
    Set lens thickness = 3.927 4kZX$ct}  
    Set lens index of refraction = 1.42672 mk#xbvvG  
    Set pupil diameter = 4 u'}SaX]0  
    DONE! ?.66B9Lld  
     
    分享到