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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 _>+Ld6.T6  
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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。 vXs"Dst  
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    模型 N8jIMb'<  
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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。 )nkY_' BV  
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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. B\~}3!j  
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    光源 ^#pEPVkY  
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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。 Q ,g\  
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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。 y29m/i:  
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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~OpofJNb  
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    图2. 字母F光源的设定方法光 V3Bz Mw\9r  
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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 )~>YH*g  
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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。 [Xkx_B  
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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。 2 ?C)&  
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    图5. 视网膜重点采样规格设定
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    脚本 KNl$3nX  
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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: +{]j]OP  
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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。 h[ ZN+M  
    余下的脚本计算与屈光度有关的所有参数。 &{:-]g\  
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    分析 !WlH'y-I  
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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。 bA 2pbjg=  
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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 BtZyn7a  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. st*gs-8jJ;  
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    Dim entity As T_ENTITY H,J8M{  
    Dim op As T_OPERATION XppOU  
    Dim mat As T_MODELMATERIAL qs6aB0ln  
    Dim A As Double *pd@.|^)m  
    Dim pupilDiam As Double ]:;&1h3'7  
    Dim eID As Long xw%0>K[  
    Dim parID As Long kfNWI#'9  
    Dim count As Integer 2oW"'43X  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double d9ihhqq3}  
    Dim tlens As Double, nlens As Double fA-7VdR`R  
    Dim curv As Double, conic As Double zs;JJk^  
    Dim ok As Long }]Tx lSp!;  
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    Sub Main 1YA% -~  
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        '用户输入对话框 X&zis1A<  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 g0H[*"hj  
            TextBox 220,21,40,21,.TextBox1 'default: 0 $]1=\ I  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 G3]4A&h9v~  
            OKButton 40,91,90,21 0(I j%Wi,  
            CancelButton 190,91,90,21 eyaNs{TV  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 w!CNRtM:~  
            TextBox 220,49,40,21,.TextBox2 'default: 4 GILfbNcd  
        End Dialog 9L9sqZUB  
        Dim dlg As UserDialog !k%#R4*>  
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        ok = Dialog (dlg) wr4:Go`  
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        If ok=0 Then    'cancel button was pressed )[  ,A_3E  
            Print "Execution cancelled." 0V]s:S  
            End "b[5]Y{ U  
        End If zT/\Cj68  
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        'Assign accommodation and pupil diameter & use defaults if field left empty ToQ"Iy?  
        If dlg.TextBox1 = "" Then BVm0{*-[|  
            A = 0           'Default accommodation 'yth'[  
        Else j|n R "!  
            A = CDbl(dlg.TextBox1) hph4`{T  
        End If \ jA~9  
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        If dlg.TextBox2 = "" Then ,[Fb[#Qqb  
            pupilDiam = 4   'Default pupil diameter (t.Nk[  
        Else |o @%dH  
            pupilDiam = CDbl(dlg.TextBox2) %SI'BJ  
        End If hSMH,^Io$  
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        Print " " HDKbF/  
        Print "Accommodation = " & A & " Diopters" 07)yG:q*x  
        Print "Pupil Diameter = " & pupilDiam & " mm" }Lv;!  
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        ' Calculate new parameters with accommodation & ~!Wym  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness _U0f=m  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens R3! t$5HG  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens q;U,s)Uz^  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens q=G+Tocv  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens &{RDM~  
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        tlens = 3.767 + 0.04*A                  'Lens thickness C>~TI,5a3  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Zov~B-Of:  
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        'Adjust parameters to account for accommodation )i<j XZ:O  
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        '************************************************************************* 2Hdu:"j  
        'Aqueous thickness (Position of Lens) ^GX)Z~  
        '************************************************************************* 9Ee'Cm  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) BD-AI  
        GetCustomElement eID, entity W`&hp6Jq  
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        parID = FindFullName( "Geometry.Arizona Eye" )  9a kH  
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        ' Delete any shift(s) in z .G^YqJ 4  
        count = 0 + )?J#g  
        While GetOperationCount(eID)>count '!$%> ||S  
            GetOperation eID, count, op qa6,z.mQ  
            If op.Type="ShiftZ" Then d1kJRJ   
                DeleteOperation eID,count ap~^Ty<>  
                count=count-1 875od  
            End If 1sCR4L:+  
            count=count+1 y?0nI<}}HK  
        Wend b[7 ]F  
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        'Set new shift in 'n|5ZhXPB  
        op.Type = "ShiftZ" ^t"'rD-I  
        op.val1 = taq uGt-l4  
        op.parent = parID Sc   
        AddOperation eID, op Tf)*4O4@'  
        Print "Set aqueous humor thickness = " & taq-0.55 _ J[  
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        '************************************************************************* :L;a:xSpn=  
        'Radius and conic constant of anterior lens !Uc T RI  
        '************************************************************************* JCaOK2XT;  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) :Yks|VJ1  
        GetConic eID, entity, curv, conic CP{cAzHO  
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        SetConic eID, entity, 1/Rant, CCant ?s _5&j7  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant o]:9')5^  
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        '************************************************************************* :yjFQ9^?&  
        'Radius and conic constant of posterior lens *4Izy14e  
        '************************************************************************* :@)>r9N  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 1QJL .  
        GetConic eID, entity, curv, conic r9lR|\Ax2U  
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        SetConic eID, entity, 1/Rpost, CCpost /=, nGk>  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost HKr Mim-  
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        '************************************************************************* qv"$Bd:]r  
        'Lens thickness (Position of posterior lens surface) f9\X>zzB2|  
        '************************************************************************* e]tDy0@  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) W];dD$Oqg  
    V!dtF,tH  
        ' Delete any z-shift(s) &I406Z f7y  
        count = 0 ?rup/4|  
        While GetOperationCount(eID)>count g4@ lM"|S  
            GetOperation eID, count, op FE{FGM q  
            If op.Type="ShiftZ" Then S+2(f> Z  
                DeleteOperation eID,count 7!$^r$t   
                count=count-1 @]#1(9P  
            End If #V}IvQl|  
            count=count+1 e!r-+.i(  
        Wend @<Yy{ ~L|  
    I9Fr5p-%O  
        'Set new z-shift EyLuO-5  
        op.Type = "ShiftZ" l0hlM#  
        op.val1 = tlens PY0j 9$i?  
        op.parent = parID TuYCR>P[  
        AddOperation eID, op e*n@j  
        Print "Set lens thickness = " & tlens Q dp)cT  
    *|E[L^  
        '************************************************************************* t.'!`5G  
        'Lens index of refraction I0 RvnMw  
        '************************************************************************* ^ K E%C;u  
        eID = FindMaterial( "Lens" ) )];K .zP  
        GetModelMaterial eID, mat evJ.<{M  
    Zsh9>]M L  
        mat.Nd = nlens I)W`sBL  
        SetModelMaterial eID, mat TNr :pE<  
        Print "Set lens index of refraction = " & nlens $lu t[o74  
     _\HQvH  
        '************************************************************************* :Xd<74Nu  
        'Pupil diameter TvQo?  
        '************************************************************************* -FCe:iY! A  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) d5z`BH.  
     =4!e&o  
        'Adjust pupil diameter (trimming volume inner hole) N{~Y J$!8  
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        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" - FlzEZ  
    "v4B5:bmqW  
        ' Adjust pupil location to just in front of the lens c:u5\&~{  
        parID = FindFullName( "Geometry.Arizona Eye" ) f0aKlhEC  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 4I?^t"  
        count = 0 P}G+4Sk  
        While GetOperationCount(eID)>count PIpi1v*qz  
            GetOperation eID, count, op g SAt@2*U2  
            If op.Type="ShiftZ" Then BFJnV.0M!  
                DeleteOperation eID,count FtC^5{V+V  
                count=count-1 8&Y^""#e)  
            End If k,F6Tx  
            count=count+1 R+,u^;\  
        Wend R n*L  
        op.Type = "ShiftZ" MO <3"@/,  
        op.val1 = taq-0.01 yq iq,=OvP  
        op.parent = parID *GN# r11d  
        AddOperation eID, op J{&H+rd  
    }k G9!sf  
        Print "Set pupil diameter = " & pupilDiam m<qJcZk  
    {3{"8-18  
        'Update AZ Eye subassembly Description xLZG:^(I  
        eID = FindFullName( "Geometry.Arizona Eye" ) 1\rz%E  
        GetEntity eID, entity (41|'eB\\  
        entity.Description = "Accommodation = " & A & "D" HuKc9U'7A  
        SetEntity eID, entity h@]XBv  
     "{Eta  
        Update v+=BCyT  
        Print "DONE!" Uwx E<=z  
         'D"C4;X  
    End Sub \K]0JH  
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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: ~B(4qK1G  
    %O;bAC_M  
    Accommodation = 4 Diopters df#$ 9 -  
    Pupil Diameter = 4 mm j;iAD:nf  
    Set aqueous humor thickness = 2.81 7y@Pa&^8  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 u21EP[[,  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 +|89>}w4  
    Set lens thickness = 3.927 @)&=%  
    Set lens index of refraction = 1.42672 5vZ^0yFQ  
    Set pupil diameter = 4 :s6o"VkW  
    DONE! U,-39mr  
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    QQ:2987619807 s)Cjc.Qs  
     
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