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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 ;Gf,$dbWn  
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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。 _?Q0yVH;,  
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    模型 VnqgN  
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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。 aYc*v5Q N3  
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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. X.^S@3[  
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    光源 j?a^fcXB  
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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。 V}c3}'_U]  
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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。 5cY([4,  
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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。 )bCw~'h*  
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    图2. 字母F光源的设定方法光 NF9fPAF%;  
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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 ,+LX.f&/8!  
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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。 Aun X[X9  
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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。 A5U//y![{  
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    图5. 视网膜重点采样规格设定
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    脚本 =8`!Ph@(  
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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: T'W)RYnwl  
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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。  3W& f^*  
    余下的脚本计算与屈光度有关的所有参数。 $q}zW%  
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    分析 H > Y0R  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 Tf0"9  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 Vp"=8p#k  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. ,q[aV 6kO  
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    Dim entity As T_ENTITY _f^JXd,7v  
    Dim op As T_OPERATION f}1B-  
    Dim mat As T_MODELMATERIAL nYA@t=t0  
    Dim A As Double 6A$  Y]u  
    Dim pupilDiam As Double ?o0ro?9j  
    Dim eID As Long $9~6M*  
    Dim parID As Long ;_bZH%o.  
    Dim count As Integer H]zi>;D  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double )\xDo<@  
    Dim tlens As Double, nlens As Double ( L{>la!  
    Dim curv As Double, conic As Double yUUg8xbpxF  
    Dim ok As Long bQTkW<7gh  
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    Sub Main Ll2yJ .C4  
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        '用户输入对话框 CO%o.j=1  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 qwf97pg$  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ON.1'Wk?  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ca@?-)  
            OKButton 40,91,90,21 7dg2-4  
            CancelButton 190,91,90,21 te<lCD6  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 h vC gd^M  
            TextBox 220,49,40,21,.TextBox2 'default: 4 {Yt@H  
        End Dialog 6jDHA3  
        Dim dlg As UserDialog ?.*^#>-  
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        ok = Dialog (dlg) w!GPPW(  
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        If ok=0 Then    'cancel button was pressed @2X{e7+D  
            Print "Execution cancelled." [5"F=tT7WP  
            End b$*1!a  
        End If qD] &&"B  
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        'Assign accommodation and pupil diameter & use defaults if field left empty w$`[C+L  
        If dlg.TextBox1 = "" Then CyHaFUbZ  
            A = 0           'Default accommodation 6=aXz2.f  
        Else b235Zm  
            A = CDbl(dlg.TextBox1) %U<1]  
        End If /Wx({N'h$  
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        If dlg.TextBox2 = "" Then o@5zf{-  
            pupilDiam = 4   'Default pupil diameter 1:.I0x!  
        Else m-wK8]t9  
            pupilDiam = CDbl(dlg.TextBox2) u`ezQvrcy  
        End If _ Vo35kA  
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        Print " " $XZC8L#  
        Print "Accommodation = " & A & " Diopters" -zSkon2Y^  
        Print "Pupil Diameter = " & pupilDiam & " mm" uOv0ut\\G  
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        ' Calculate new parameters with accommodation h!zev~u1)`  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness %fF0<c^-U  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens R?D c*,  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 'v~%rhq3  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens #X`qkW.T<  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 141G~@-  
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        tlens = 3.767 + 0.04*A                  'Lens thickness BYKONZu  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction .@kjC4m  
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        'Adjust parameters to account for accommodation tD j/!L`  
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        '************************************************************************* Vx#n0z  
        'Aqueous thickness (Position of Lens) VUQx"R9-  
        '************************************************************************* X$0&tmum  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 4?c4GT9(6S  
        GetCustomElement eID, entity ; `Vbl_"L  
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        parID = FindFullName( "Geometry.Arizona Eye" ) _@/nc:)H  
    '[zy%<2sL  
        ' Delete any shift(s) in z A?;KfVq  
        count = 0 6|@\\\l  
        While GetOperationCount(eID)>count B*AF8wX|  
            GetOperation eID, count, op +#LD@)G  
            If op.Type="ShiftZ" Then MRb6O!$`C  
                DeleteOperation eID,count C?h}n4\B^?  
                count=count-1 huTWoMU  
            End If hVl^vw7o  
            count=count+1  IPDQ  
        Wend $%"?0S  
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        'Set new shift in 6%\&m|S  
        op.Type = "ShiftZ" VQ(l=k:}2  
        op.val1 = taq 1R"?X'w  
        op.parent = parID  C4.g}q  
        AddOperation eID, op 6xT" j)h  
        Print "Set aqueous humor thickness = " & taq-0.55 nN*:"F/^  
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        '************************************************************************* 4.&hV?Kxz  
        'Radius and conic constant of anterior lens k%TjRf{p  
        '************************************************************************* 8Ben}j)H  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) d>-k-X-[  
        GetConic eID, entity, curv, conic U:+wt}-T"  
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        SetConic eID, entity, 1/Rant, CCant |<Rf^"T  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 3j} @}2D  
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        '************************************************************************* `F,*NESv  
        'Radius and conic constant of posterior lens S @tpd'  
        '************************************************************************* wxW\L!@  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) }\oy%]_mY  
        GetConic eID, entity, curv, conic %]\IC(q  
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        SetConic eID, entity, 1/Rpost, CCpost }Q#3\z5  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost qf?X:9Wt  
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        '************************************************************************* ?_BK(kL_  
        'Lens thickness (Position of posterior lens surface) Jd-u ?  
        '*************************************************************************  X0&[cyP!  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" )  WgayH  
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        ' Delete any z-shift(s) :J~sz)n4  
        count = 0 >[&Zs3>  
        While GetOperationCount(eID)>count `44 }kkBT  
            GetOperation eID, count, op o^*k   
            If op.Type="ShiftZ" Then W"&Y7("y  
                DeleteOperation eID,count [~U CYYl  
                count=count-1 :+Okv$v4  
            End If $*N)\>~X  
            count=count+1 Pp ~:e}  
        Wend 4O1[D? )`x  
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        'Set new z-shift am(jmf::  
        op.Type = "ShiftZ" /AhN$)(O  
        op.val1 = tlens l 4e`-7  
        op.parent = parID TD6MP9L  
        AddOperation eID, op {6Qd,CX  
        Print "Set lens thickness = " & tlens JV_V2L1Ut  
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        '************************************************************************* 0fP-[7P  
        'Lens index of refraction L.R4 iN  
        '************************************************************************* ZT1IN6;8W  
        eID = FindMaterial( "Lens" ) Lq cHsUFj  
        GetModelMaterial eID, mat Xn3 \a81  
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        mat.Nd = nlens iW$f1=i  
        SetModelMaterial eID, mat ZgH(,g,TU  
        Print "Set lens index of refraction = " & nlens Hy| X>Z  
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        '************************************************************************* SQ0t28N3h  
        'Pupil diameter pj/w9j G6  
        '************************************************************************* i?D KKjN$  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ai@hQJ*  
    'pQ\BH  
        'Adjust pupil diameter (trimming volume inner hole) 6>R|B?I%  
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        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" o{I]c#W  
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        ' Adjust pupil location to just in front of the lens `S+B-I0  
        parID = FindFullName( "Geometry.Arizona Eye" ) lVR a{._m  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) gK+/wTQ%  
        count = 0 o'auCa,N  
        While GetOperationCount(eID)>count Yj/[I\I"m  
            GetOperation eID, count, op 29~Bu5  
            If op.Type="ShiftZ" Then ;f l3'.S[  
                DeleteOperation eID,count Ks_B%d  
                count=count-1 ux=0N]lc  
            End If T2p;#)dP  
            count=count+1 _DAj$$ Ru4  
        Wend }<KQ +  
        op.Type = "ShiftZ" 8 bpYop7 L  
        op.val1 = taq-0.01 A[6D40o  
        op.parent = parID hH])0C  
        AddOperation eID, op lOJ3_8  
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        Print "Set pupil diameter = " & pupilDiam [44C`x[8M+  
    C<u<:4^H  
        'Update AZ Eye subassembly Description Pt^SlX^MM  
        eID = FindFullName( "Geometry.Arizona Eye" ) RI</T3%~  
        GetEntity eID, entity (//f"c]/  
        entity.Description = "Accommodation = " & A & "D" \;F_QV  
        SetEntity eID, entity /lqVMlz\77  
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        Update @M_p3[c\  
        Print "DONE!" DSX.84  
         OD~B2MpM>  
    End Sub .|Y&,?k| Y  
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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: yG..B  
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    Accommodation = 4 Diopters TOC2[m c'  
    Pupil Diameter = 4 mm 'vc>uY  
    Set aqueous humor thickness = 2.81 W< sa6,$  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 (m%A>e B  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 I2G:jMPy  
    Set lens thickness = 3.927 zvAUF8'_  
    Set lens index of refraction = 1.42672 KYN{Dh]-}  
    Set pupil diameter = 4 RP|/rd]-k  
    DONE! -H-:b7  
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