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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 T+p ?VngF  
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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。 dLl/V3C6t  
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    模型 9xL8 ];-  
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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。 Rn6;@Cw  
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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. jA@jsv  
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    光源 RGd@3OjN  
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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。 (ZR+(+i,  
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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。 _7df(+.{<A  
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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。 E`68Z/%  
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    图2. 字母F光源的设定方法光 ,z A9*  
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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 Ni]V)wGE;  
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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。 R5PXX&Q  
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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。 rqJ'm?>cr  
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    图5. 视网膜重点采样规格设定
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    脚本 zJC!MeN  
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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: AAbI+L0m{  
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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。 LIzdP,^pc  
    余下的脚本计算与屈光度有关的所有参数。 )F_0('=t  
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    分析 kg0X2^#b  
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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。 ./SDZ:5/  
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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 lG[@s 'j  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. c3S}(8g5.  
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    Dim entity As T_ENTITY +qN}oyL  
    Dim op As T_OPERATION ~SKV%  
    Dim mat As T_MODELMATERIAL eBUexxBY  
    Dim A As Double 0PfjD  
    Dim pupilDiam As Double c*>8VW>  
    Dim eID As Long 9]u=b\fzZ  
    Dim parID As Long 'mwgHo<u  
    Dim count As Integer 5UWj#|t  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double o[$~  
    Dim tlens As Double, nlens As Double c? Z M<Y"  
    Dim curv As Double, conic As Double  kwI[BF  
    Dim ok As Long il8n K  
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    Sub Main QMO.Bnek  
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        '用户输入对话框 /\7E&n:)2  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 2A>s a3\  
            TextBox 220,21,40,21,.TextBox1 'default: 0 e3o?=;  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1  %XF>k)  
            OKButton 40,91,90,21 "2l$}G  
            CancelButton 190,91,90,21 H$D),s gv  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 2Dc2uU@`r  
            TextBox 220,49,40,21,.TextBox2 'default: 4 <8J_[ S  
        End Dialog HB|R1<t;HB  
        Dim dlg As UserDialog !841/TRb  
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        ok = Dialog (dlg) MUQj7.rNa  
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        If ok=0 Then    'cancel button was pressed -uk}Fou  
            Print "Execution cancelled." ]Rk4"i  
            End }}?,({T|n  
        End If )~X.x"}8k  
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        'Assign accommodation and pupil diameter & use defaults if field left empty p<Oz"6_/~  
        If dlg.TextBox1 = "" Then &':Ecmo~`  
            A = 0           'Default accommodation 9Sey&x  
        Else 0<3->uK  
            A = CDbl(dlg.TextBox1) o=zr]vv  
        End If <%Al(Lm0  
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        If dlg.TextBox2 = "" Then o=]\Jy  
            pupilDiam = 4   'Default pupil diameter !VDNqW  
        Else Be$v%4  
            pupilDiam = CDbl(dlg.TextBox2)  `1`Qu!  
        End If k_?Z6RE>  
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        Print " " >%\&tS'  
        Print "Accommodation = " & A & " Diopters" [d?tf  
        Print "Pupil Diameter = " & pupilDiam & " mm" 7 /6 Zp?  
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        ' Calculate new parameters with accommodation :pH3M[7  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ,J&\) yTP  
    Fp&tJ]=B.  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens {j8M78}3  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens H`bS::JI-  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens \=qZ),bU@  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens +HT?> k  
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        tlens = 3.767 + 0.04*A                  'Lens thickness (Q?@LzCjy  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction /lS5B6NU  
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        'Adjust parameters to account for accommodation d-cW47  
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        '************************************************************************* T -p~8=I  
        'Aqueous thickness (Position of Lens) oTN:Q"oK7?  
        '************************************************************************* k>)Uyw$!  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) yz<$?Gblz  
        GetCustomElement eID, entity & [z<p  
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        parID = FindFullName( "Geometry.Arizona Eye" ) Q?2Gw N  
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        ' Delete any shift(s) in z ]!X[[w)  
        count = 0 K>vi9,4/ks  
        While GetOperationCount(eID)>count U#G<cV79  
            GetOperation eID, count, op .% 79(r^  
            If op.Type="ShiftZ" Then 2Krh&  
                DeleteOperation eID,count F};T<#  
                count=count-1 ]++,7Z\AU  
            End If YuUJgt .1  
            count=count+1 &n'@L9v81  
        Wend 0j :u.x  
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        'Set new shift in G1a56TIN~  
        op.Type = "ShiftZ" YB1Jv[  
        op.val1 = taq L0)w~F ?m  
        op.parent = parID 2YQ;Kh"S   
        AddOperation eID, op `>- 56 %  
        Print "Set aqueous humor thickness = " & taq-0.55 PjP6^"  
    Y?6}r;<  
        '************************************************************************* ti^=aB   
        'Radius and conic constant of anterior lens TbD $lx3>  
        '************************************************************************* QM24cm T  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) H]}mg='kI  
        GetConic eID, entity, curv, conic NY6;\ 7!n  
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        SetConic eID, entity, 1/Rant, CCant }9V0Cu1  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ;$67GK  
    <@$+uZt+  
        '************************************************************************* Zb7%$1)L~  
        'Radius and conic constant of posterior lens CofTTYl  
        '************************************************************************* PpLiH9}  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 9PUobV_^Wo  
        GetConic eID, entity, curv, conic Ob/i_  
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        SetConic eID, entity, 1/Rpost, CCpost cw,|,uXq 6  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost '0=mV"#H{  
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        '************************************************************************* r>}z|I'  
        'Lens thickness (Position of posterior lens surface) h$#PboLd  
        '************************************************************************* 82 dmlPwJC  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) XmP,3KG2{S  
    ^u2x26].  
        ' Delete any z-shift(s) RBfzti6  
        count = 0 Y>T<Qn^D  
        While GetOperationCount(eID)>count }G "EdhSl  
            GetOperation eID, count, op W!"Oho'  
            If op.Type="ShiftZ" Then <J>k%,:B  
                DeleteOperation eID,count :r2d%:h%2  
                count=count-1 ^ E_chx-e}  
            End If _f~$iY  
            count=count+1 JAM]neKiX  
        Wend *&tTiv{^  
    3mHP=)  
        'Set new z-shift DS9-i2  
        op.Type = "ShiftZ"  6HPuCP  
        op.val1 = tlens GO.7IL{ {  
        op.parent = parID Z^BZH/I?  
        AddOperation eID, op P 'o]#Az  
        Print "Set lens thickness = " & tlens /'zXb_R,$  
    -Mf-8zw8G  
        '************************************************************************* =4sx(<  
        'Lens index of refraction xLb=^Xjec  
        '************************************************************************* 3<l}gB'S[  
        eID = FindMaterial( "Lens" ) | N}*  
        GetModelMaterial eID, mat 6b%IPbb  
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        mat.Nd = nlens (J?_~(,`"  
        SetModelMaterial eID, mat kT]jJbb"  
        Print "Set lens index of refraction = " & nlens z7z9lDS  
    *Z\AO'h=Z  
        '************************************************************************* .2U3_1dX  
        'Pupil diameter ESk:$`P  
        '************************************************************************* @FZ_[CYg  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) #|3,DZ|)F  
    ,hr v  
        'Adjust pupil diameter (trimming volume inner hole) >Q'*~S@v3  
    D>^g2!b:  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" DAg*  
    Pe-rwM  
        ' Adjust pupil location to just in front of the lens cq5^7.  
        parID = FindFullName( "Geometry.Arizona Eye" ) M]M>z>1*v  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) P_b!^sq9  
        count = 0 %iME[| u&  
        While GetOperationCount(eID)>count 8GRB6-.h  
            GetOperation eID, count, op `Kn+d~S4  
            If op.Type="ShiftZ" Then u\M xQIo'u  
                DeleteOperation eID,count zk!7TUZ">w  
                count=count-1 eh>FYx( S  
            End If .LDp.#d9r1  
            count=count+1 <o[3*59  
        Wend 6xA xLZz<  
        op.Type = "ShiftZ" +sTPTCLE  
        op.val1 = taq-0.01 ~g%Ht# <  
        op.parent = parID {LVA_7@  
        AddOperation eID, op ? HNuffk  
    SkC.A ?  
        Print "Set pupil diameter = " & pupilDiam Vugb;5Vl  
    ,j9?9Z7R  
        'Update AZ Eye subassembly Description ,jtaTG.>  
        eID = FindFullName( "Geometry.Arizona Eye" ) pr1bsrMuL  
        GetEntity eID, entity LE)$_i8gX  
        entity.Description = "Accommodation = " & A & "D" I-1NZgv  
        SetEntity eID, entity +S+=lu _  
    H:9G/Nev  
        Update \{!,a  
        Print "DONE!" z;?j+ZsdH  
         Ycx}FYTY  
    End Sub eE=2~ ylU  
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    如果屈光度是4,光瞳直径是4,则会输出如下数据: `iN\@)E  
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    Accommodation = 4 Diopters l]#=I7 6  
    Pupil Diameter = 4 mm s[dIWYs#  
    Set aqueous humor thickness = 2.81 H'7s`^- >I  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 _<DOA:'v  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 qJf\,7mi  
    Set lens thickness = 3.927 $.:x3TsA  
    Set lens index of refraction = 1.42672 %3|/t-US  
    Set pupil diameter = 4 ~)`\ j  
    DONE! `m8WLj  
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    QQ:2987619807 _ WPt zL  
     
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